Build: Remove dependency on SVN since we don't use it anymore anywhere.

Transceiver52M: fixup for c5da660: We don't need to check for NULL with delete operator.
CommonLibs: Adding a new ThreadsTest testsuite.
2025-11-01 20:53:35 +00:00 · 2013-08-29 01:58:20 +04:00 · 2013-07-16 07:33:57 +04:00 · 2013-07-14 23:11:54 +04:00 · 2013-07-14 23:11:54 +04:00 · 2013-07-14 23:11:54 +04:00
30 changed files with 2166 additions and 1462 deletions
--- a/CommonLibs/Configuration.cpp
+++ b/CommonLibs/Configuration.cpp
@@ -35,7 +35,7 @@
 #ifdef DEBUG_CONFIG
 #define	debugLogEarly gLogEarly
 #else
-#define	debugLogEarly
+#define	debugLogEarly(x,y,z)
 #endif


--- a/CommonLibs/Interthread.h
+++ b/CommonLibs/Interthread.h
@@ -1,5 +1,6 @@
 /*
 * Copyright 2008, 2011 Free Software Foundation, Inc.
+* Copyright 2013 Alexander Chemeris <Alexander.Chemeris@fairwaves.ru>
 *
 * This software is distributed under the terms of the GNU Affero Public License.
 * See the COPYING file in the main directory for details.
@@ -41,6 +42,7 @@
 //@{


+// UNUSED in osmo-trx
 /** Pointer FIFO for interthread operations.  */
 // (pat) The elements in the queue are type T*, and
 // the Fifo class implements the underlying queue.
@@ -98,7 +100,7 @@ template <class T, class Fifo=PointerFIFO> class InterthreadQueue {
 	{
 		ScopedLock lock(mLock);
 		T* retVal = (T*)mQ.get();
-		while (retVal==NULL) {
+		if (retVal==NULL) {
 			mWriteSignal.wait(mLock);
 			retVal = (T*)mQ.get();
 		}
@@ -155,6 +157,7 @@ template <class T, class Fifo=PointerFIFO> class InterthreadQueue {
 	}
 };

+// UNUSED in osmo-trx
 // (pat) Identical to above but with the threading problem fixed.
 template <class T, class Fifo=PointerFIFO> class InterthreadQueue2 {

@@ -276,6 +279,7 @@ template <class T, class Fifo=PointerFIFO> class InterthreadQueue2 {



+// UNUSED in osmo-trx
 /** Pointer FIFO for interthread operations.  */
 template <class T> class InterthreadQueueWithWait {

@@ -380,7 +384,7 @@ template <class T> class InterthreadQueueWithWait {



-
+// UNUSED in osmo-trx
 /** Thread-safe map of pointers to class D, keyed by class K. */
 template <class K, class D > class InterthreadMap {

@@ -644,7 +648,7 @@ template <class T, class C = std::vector<T*>, class Cmp = PointerCompare<T> > cl



-
+// UNUSED in osmo-trx
 class Semaphore {

 	private:
--- a/CommonLibs/InterthreadTest.cpp
+++ b/CommonLibs/InterthreadTest.cpp
@@ -1,5 +1,6 @@
 /*
 * Copyright 2008 Free Software Foundation, Inc.
+* Copyright 2013 Alexander Chemeris <Alexander.Chemeris@fairwaves.ru>
 *
 *
 * This software is distributed under the terms of the GNU Affero Public License.
@@ -27,66 +28,91 @@

 #include "Threads.h"
 #include "Interthread.h"
+#include "Configuration.h"
 #include <iostream>

 using namespace std;

+ConfigurationTable gConfig;

 InterthreadQueue<int> gQ;
 InterthreadMap<int,int> gMap;

-void* qWriter(void*)
+class QueueWriter : public Thread
 {
-	int *p;
-	for (int i=0; i<20; i++) {
+public:
+	QueueWriter() : Thread("QueueWriter") {}
+
+protected:
+	virtual void runThread()
+	{
+		int *p;
+		for (int i=0; i<20; i++) {
+			p = new int;
+			*p = i;
+			COUT("queue write " << *p);
+			gQ.write(p);
+			msleep(1);
+		}
 		p = new int;
-		*p = i;
-		COUT("queue write " << *p);
+		*p = -1;
 		gQ.write(p);
-		if (random()%2) sleep(1);
 	}
-	p = new int;
-	*p = -1;
-	gQ.write(p);
-	return NULL;
-}
+};

-void* qReader(void*)
+class QueueReader : public Thread
 {
-	bool done = false;
-	while (!done) {
-		int *p = gQ.read();
-		COUT("queue read " << *p);
-		if (*p<0) done=true;
-		delete p;
+public:
+	QueueReader() : Thread("QueueReader") {}
+
+protected:
+	virtual void runThread()
+	{
+		bool done = false;
+		while (!done) {
+			int *p = gQ.read();
+			COUT("queue read " << *p);
+			if (*p<0) done=true;
+			delete p;
+		}
 	}
-	return NULL;
-}
+};


-void* mapWriter(void*)
+class MapWriter : public Thread
 {
-	int *p;
-	for (int i=0; i<20; i++) {
-		p = new int;
-		*p = i;
-		COUT("map write " << *p);
-		gMap.write(i,p);
-		if (random()%2) sleep(1);
-	}
-	return NULL;
-}
+public:
+	MapWriter() : Thread("MapWriter") {}

-void* mapReader(void*)
-{
-	for (int i=0; i<20; i++) {
-		int *p = gMap.read(i);
-		COUT("map read " << *p);
-		// InterthreadMap will delete the pointers
-		// delete p;
+protected:
+	virtual void runThread()
+	{
+		int *p;
+		for (int i=0; i<20; i++) {
+			p = new int;
+			*p = i;
+			COUT("map write " << *p);
+			gMap.write(i,p);
+			msleep(1);
+		}
 	}
-	return NULL;
-}
+};
+
+class MapReader : public Thread
+{
+public:
+	MapReader() : Thread("MapReader") {}
+
+protected:
+	virtual void runThread()
+	{
+		for (int i=0; i<20; i++) {
+			int *p = gMap.read(i);
+			COUT("map read " << *p);
+			// InterthreadMap will delete the pointers
+		}
+	}
+};



@@ -95,20 +121,25 @@ void* mapReader(void*)

 int main(int argc, char *argv[])
 {
-	Thread qReaderThread;
-	qReaderThread.start(qReader,NULL);
-	Thread mapReaderThread;
-	mapReaderThread.start(mapReader,NULL);
+	COUT("TEST 1: InterthreadQueue")
+	QueueReader qReaderThread;
+	QueueWriter qWriterThread;
+	qReaderThread.startThread();
+	qWriterThread.startThread();
+	// stopThread() will wait for a thread to stop for 5 seconds, which
+	// is more than enough for this test to finish.
+	qReaderThread.stopThread();
+	qWriterThread.stopThread();

-	Thread qWriterThread;
-	qWriterThread.start(qWriter,NULL);
-	Thread mapWriterThread;
-	mapWriterThread.start(mapWriter,NULL);
-
-	qReaderThread.join();
-	qWriterThread.join();
-	mapReaderThread.join();
-	mapWriterThread.join();
+	COUT("TEST 2: InterthreadMap")
+	MapReader mapReaderThread;
+	mapReaderThread.startThread();
+	MapWriter mapWriterThread;
+	mapWriterThread.startThread();
+	// stopThread() will wait for a thread to stop for 5 seconds, which
+	// is more than enough for this test to finish.
+	mapReaderThread.stopThread();
+	mapWriterThread.stopThread();
 }


--- a/CommonLibs/Makefile.am
+++ b/CommonLibs/Makefile.am
@@ -44,6 +44,7 @@ libcommon_la_SOURCES = \
 	Utils.cpp

 noinst_PROGRAMS = \
+	ThreadsTest \
 	BitVectorTest \
 	InterthreadTest \
 	SocketsTest \
@@ -80,12 +81,16 @@ URLEncodeTest_LDADD = libcommon.la
 BitVectorTest_SOURCES = BitVectorTest.cpp
 BitVectorTest_LDADD = libcommon.la $(SQLITE_LA)

+ThreadsTest_SOURCES = ThreadsTest.cpp
+ThreadsTest_LDADD = libcommon.la $(SQLITE_LA)
+ThreadsTest_LDFLAGS = -lpthread
+
 InterthreadTest_SOURCES = InterthreadTest.cpp
-InterthreadTest_LDADD = libcommon.la
+InterthreadTest_LDADD = libcommon.la $(SQLITE_LA)
 InterthreadTest_LDFLAGS = -lpthread

 SocketsTest_SOURCES = SocketsTest.cpp
-SocketsTest_LDADD = libcommon.la
+SocketsTest_LDADD = libcommon.la $(SQLITE_LA)
 SocketsTest_LDFLAGS = -lpthread

 TimevalTest_SOURCES = TimevalTest.cpp
--- a/CommonLibs/Sockets.cpp
+++ b/CommonLibs/Sockets.cpp
@@ -1,5 +1,6 @@
 /*
 * Copyright 2008, 2010 Free Software Foundation, Inc.
+* Copyright 2013 Alexander Chemeris <Alexander.Chemeris@fairwaves.ru>
 *
 *
 * This software is distributed under the terms of the GNU Affero Public License.
@@ -129,6 +130,11 @@ void DatagramSocket::close()
 	::close(mSocketFD);
 }

+void DatagramSocket::shutdown()
+{
+  ::shutdown(mSocketFD, SHUT_RDWR);
+}
+

 DatagramSocket::~DatagramSocket()
 {
--- a/CommonLibs/Sockets.h
+++ b/CommonLibs/Sockets.h
@@ -1,5 +1,6 @@
 /*
 * Copyright 2008, 2010 Free Software Foundation, Inc.
+* Copyright 2013 Alexander Chemeris <Alexander.Chemeris@fairwaves.ru>
 *
 * This software is distributed under the terms of the GNU Affero Public License.
 * See the COPYING file in the main directory for details.
@@ -134,6 +135,11 @@ public:
 	/** Close the socket. */
 	void close();

+  /** Shutdown the socket without destroying the descriptor
+   *  Use this to interrupt blocking read()
+   */
+  void shutdown();
+
 };


--- a/CommonLibs/SocketsTest.cpp
+++ b/CommonLibs/SocketsTest.cpp
@@ -1,5 +1,6 @@
 /*
 * Copyright 2008 Free Software Foundation, Inc.
+* Copyright 2013 Alexander Chemeris <Alexander.Chemeris@fairwaves.ru>
 *
 *
 * This software is distributed under the terms of the GNU Affero Public License.
@@ -28,59 +29,73 @@

 #include "Sockets.h"
 #include "Threads.h"
-#include <stdio.h>
+#include "Configuration.h"
+#include "Timeval.h"
 #include <stdlib.h>

+ConfigurationTable gConfig;

 static const int gNumToSend = 10;


-void *testReaderIP(void *)
+class TestReaderIP : public Thread
 {
-	UDPSocket readSocket(5934, "localhost", 5061);
-	readSocket.nonblocking();
-	int rc = 0;
-	while (rc<gNumToSend) {
-		char buf[MAX_UDP_LENGTH];
-		int count = readSocket.read(buf);
-		if (count>0) {
-			COUT("read: " << buf);
-			rc++;
-		} else {
-			sleep(2);
+public:
+	TestReaderIP() : Thread("TestReaderIP") {}
+
+protected:
+	virtual void runThread()
+	{
+		UDPSocket readSocket(5934, "localhost", 5061);
+		readSocket.nonblocking();
+		int rc = 0;
+		while (rc<gNumToSend) {
+			char buf[MAX_UDP_LENGTH];
+			int count = readSocket.read(buf);
+			if (count>0) {
+				COUT("IP read: " << buf);
+				rc++;
+			} else {
+				COUT("IP sleeping...");
+				sleep(2);
+			}
 		}
 	}
-	return NULL;
-}
+};

-
-
-void *testReaderUnix(void *)
+class TestReaderUnix : public Thread
 {
-	UDDSocket readSocket("testDestination");
-	readSocket.nonblocking();
-	int rc = 0;
-	while (rc<gNumToSend) {
-		char buf[MAX_UDP_LENGTH];
-		int count = readSocket.read(buf);
-		if (count>0) {
-			COUT("read: " << buf);
-			rc++;
-		} else {
-			sleep(2);
+public:
+	TestReaderUnix() : Thread("TestReaderUnix") {}
+
+protected:
+	virtual void runThread()
+	{
+		UDDSocket readSocket("testDestination");
+		readSocket.nonblocking();
+		int rc = 0;
+		while (rc<gNumToSend) {
+			char buf[MAX_UDP_LENGTH];
+			int count = readSocket.read(buf);
+			if (count>0) {
+				COUT("UNIX read: " << buf);
+				rc++;
+			} else {
+				COUT("UNIX sleeping...");
+				sleep(2);
+			}
 		}
 	}
-	return NULL;
-}
+};


 int main(int argc, char * argv[] )
 {

-  Thread readerThreadIP;
-  readerThreadIP.start(testReaderIP,NULL);
-  Thread readerThreadUnix;
-  readerThreadUnix.start(testReaderUnix,NULL);
+  TestReaderIP readerThreadIP;
+  TestReaderUnix readerThreadUnix;
+  readerThreadIP.startThread();
+  readerThreadUnix.startThread();

  UDPSocket socket1(5061, "127.0.0.1",5934);
  UDDSocket socket1U("testSource","testDestination");
@@ -92,12 +107,10 @@ int main(int argc, char * argv[] )

  for (int i=0; i<gNumToSend; i++) {
    socket1.write("Hello IP land");	
-	socket1U.write("Hello Unix domain");
-	sleep(1);
+    socket1U.write("Hello Unix domain");
+    msleep(1);
  }

-  readerThreadIP.join();
-  readerThreadUnix.join();
 }

 // vim: ts=4 sw=4
--- a/CommonLibs/Threads.cpp
+++ b/CommonLibs/Threads.cpp
@@ -1,5 +1,6 @@
 /*
 * Copyright 2008 Free Software Foundation, Inc.
+* Copyright 2013 Alexander Chemeris <Alexander.Chemeris@fairwaves.ru>
 *
 *
 * This software is distributed under the terms of the GNU Affero Public License.
@@ -29,11 +30,26 @@

 #include "Threads.h"
 #include "Timeval.h"
+#include "Logger.h"
+#include <pthread.h>
+#include <sys/types.h>
+#include <errno.h> // for ETIMEDOUT
+#include <sys/syscall.h> // for SYS_gettid
+#include <sys/prctl.h> // Linux specific, for prctl(PR_SET_NAME)
+
+// Make sure we get MCL_CURRENT and MCL_FUTURE (for mlockall) on OS X 10.3
+#define _P1003_1B_VISIBLE
+#include <sys/mman.h>
+#undef _P1003_1B_VISIBLE


 using namespace std;

+#define POSIX_OK           0
+#define POSIX_NO_WAIT      0
+#define POSIX_WAIT_FOREVER (-1)

+static inline int gettid() {return syscall(SYS_gettid);}


 Mutex gStreamLock;		///< Global lock to control access to cout and cerr.
@@ -95,27 +111,235 @@ Mutex::~Mutex()


 /** Block for the signal up to the cancellation timeout. */
-void Signal::wait(Mutex& wMutex, unsigned timeout) const
+int Signal::wait(Mutex& wMutex, unsigned timeout) const
 {
 	Timeval then(timeout);
 	struct timespec waitTime = then.timespec();
-	pthread_cond_timedwait(&mSignal,&wMutex.mMutex,&waitTime);
+	return pthread_cond_timedwait(&mSignal,&wMutex.mMutex,&waitTime);
 }

-
-void Thread::start(void *(*task)(void*), void *arg)
+Thread::Thread(const string &name, size_t stackSize)
+: mThreadId((pthread_t)0)
+, mThreadName(name)
+, mStackSize(stackSize)
+, mThreadState(THREAD_STATE_IDLE)
+, mThreadData(NULL)
 {
-	assert(mThread==((pthread_t)0));
-	bool res;
-	// (pat) Moved initialization to constructor to avoid crash in destructor.
-	//res = pthread_attr_init(&mAttrib);
-	//assert(!res);
-	res = pthread_attr_setstacksize(&mAttrib, mStackSize);
-	assert(!res);
-	res = pthread_create(&mThread, &mAttrib, task, arg);
-	assert(!res);
 }

+Thread::~Thread()
+{
+    stopThread();
+}

+void *Thread::threadAdaptor(void *data)
+{
+    Thread *pThread = (Thread*)data;
+
+    // If we ever receive a thread cancel request, it means that the Thread
+    // object is in the process of being destroyed.  To avoid the situation
+    // where a thread attempts to run after its containing Thread object has
+    // been freed, we set the thread up so that the cancel takes effect
+    // immediately (as opposed to waiting until the next thread cancellation
+    // point).
+    pthread_setcanceltype(PTHREAD_CANCEL_ASYNCHRONOUS, NULL);
+
+    // =====================================================================
+    // Synchronize with the start() in the parent thread.
+    {
+        // 1. Lock synchronization mutex.
+        ScopedLock lock(pThread->mThreadStartupMutex);
+
+        // 2. Btw, set the thread name, while we're inside the mutex.
+        // FIXME: This works on Linux with glibc >= 2.12. Under *BSD and MacOS X
+        //        this function has different arguments.
+//        pthread_setname_np(pThread->mThreadId, pThread->mThreadName.c_str());
+        // FIXME: For some reason the previous call doesn't work on my Ubuntu 12.04,
+        //        so we use this one which works.
+        prctl(PR_SET_NAME, pThread->mThreadName.c_str());
+
+        // 3. Signal that we've started.
+        pThread->mThreadStartStopEvent.signal();
+
+        // 4. Wait until start() finishes its initialization.
+        //
+        // The actual thread is created and started with pthread_create(), then
+        // start() does its housekeeping and sets mThreadState=THREAD_STATE_RUNNING.
+        // If we allow Thread::run() to start before this initialization completes,
+        // callers might think (among other things) that the thread is not started
+        // while it's actually started.
+        pThread->mThreadInitializedEvent.wait(pThread->mThreadStartupMutex);
+    }
+    // Synchronization with the parent thread is finished.
+    // =====================================================================
+
+    // Log Thread ID for debugging purposes
+    LOG(INFO) << "Thread started: " << pThread->mThreadName
+              << " with lwp=" << gettid() << ", pid=" << getpid();
+
+    // Keep all memory locked into physical mem, to guarantee realtime-behaviour
+    int res = mlockall(MCL_CURRENT|MCL_FUTURE);
+    if (res != POSIX_OK) {
+      LOG(WARNING) << "Failed to lock memory for thread: " << pThread->mThreadName;
+    }
+
+    // Run the actual code
+    pThread->runThread();
+
+    // Huh, we're done. Signal to a (potentially) waiting stop()'s.
+    {
+        ScopedLock lock(pThread->mThreadStateMutex);
+        pThread->mThreadState = THREAD_STATE_IDLE;
+        pThread->mThreadStartStopEvent.broadcast();
+    }
+
+    return NULL;
+}
+
+Thread::ReturnStatus Thread::startThread(void *data)
+{
+    pthread_attr_t attrib;
+//    timeval        threadStartTime;
+//    timespec       threadStartTimeout;
+    bool res;
+
+    // Lock startup synchronization mutex. It will be used in conjunction with
+    // mThreadInitializedEvent and mThreadStartStopEvent conditional variables.
+    ScopedLock lock(mThreadStartupMutex);
+
+    {
+        ScopedLock lock(mThreadStateMutex);
+        if (mThreadState != THREAD_STATE_IDLE)
+            return ALREADY_STARTED;
+        mThreadState = THREAD_STATE_STARTING;
+    }
+
+    // Save thread data pointer
+    mThreadData = data;
+
+    LOG(DEBUG) <<  "Starting thread " << mThreadName << " (" << this << ")";
+
+    // construct thread attribute
+    res = pthread_attr_init(&attrib);
+    if (res != POSIX_OK) {
+        LOG(ALERT) <<  "pthread_attr_init failed, returned " << res
+                   << " in " << mThreadName << " (" << this << ")";
+    }
+
+
+    // Set the thread stack size
+    res = pthread_attr_setstacksize(&attrib, mStackSize);
+    if (res != POSIX_OK)
+    {
+        LOG(ALERT) <<  "pthread_attr_setstacksize failed, returned " << res
+                   << " in " << mThreadName << " (" << this << ")";
+    }
+
+    // Create the thread detached
+    res = pthread_attr_setdetachstate(&attrib, PTHREAD_CREATE_DETACHED);
+    if (res != POSIX_OK)
+    {
+       LOG(ALERT) <<  "pthread_attr_setdetachstate failed, returned " << res
+                  << " in " << mThreadName << " (" << this << ")";
+    }
+
+    // =====================================================================
+    // Start the thread and synchronize with it
+
+    // Start the thread!
+    res = pthread_create(&mThreadId, &attrib, threadAdaptor, (void *)this);
+    // Attributes are no longer needed.
+    pthread_attr_destroy(&attrib);
+
+    if (res != POSIX_OK)
+    {
+        LOG(ALERT) << "pthread_create failed, returned " << res
+                   << " in " << mThreadName << " (" << this << ")";
+
+        return PTHREAD_ERROR;
+    }
+
+    // Wait for the thread to startup.
+    res = mThreadStartStopEvent.wait(mThreadStartupMutex, THREAD_STARTUP_TIMEOUT*1000);
+
+    // If the thread does not start in THREAD_STARTUP_TIMEOUT seconds,
+    // then something is terribly wrong here.
+    if (res == ETIMEDOUT)
+    {
+       LOG(ALERT) << "thread " << mThreadName << " (" << this << ") hasn't started up in "
+                  << THREAD_STARTUP_TIMEOUT << " seconds. Bailing out.";
+
+       return RETURN_TIMEOUT;
+    }
+
+    // We're done with the initialization.
+    ackThreadStart();
+
+    // ToDo: Add other initialization here, e.g. adding this thread to a list of all threads.
+
+    // Startup initialization finished. Signal this to started thread, so
+    // it could go on.
+    mThreadInitializedEvent.signal();
+
+    return RETURN_OK;
+}
+
+Thread::ReturnStatus Thread::stopThread()
+{
+    int res;
+
+    LOG(DEBUG) <<  "Stopping thread " << mThreadName << " (" << this << ")";
+
+    while (1) {
+        ScopedLock lock(mThreadStateMutex);
+
+        switch (mThreadState) {
+        case THREAD_STATE_IDLE:
+            // Nothing to do.
+            return RETURN_OK;
+
+        case THREAD_STATE_STARTING:
+            // Something is wrong in thi world.
+            assert(mThreadState != THREAD_STATE_STARTING);
+            LOG(ALERT) << "Trying to stop thread " << mThreadName
+                       << " (" << this << ") while it's trying to start.";
+            return WRONG_STATE;
+
+        case THREAD_STATE_RUNNING:
+            // Request shudown
+            mThreadState = THREAD_STATE_STOPPING;
+            // no "break" here to fall through to the next case
+
+        case THREAD_STATE_STOPPING:
+            // Wait for the thread to stop.
+            LOG(DEBUG) << "Waiting for thread " << mThreadName << " (" << this << ") to stop.";
+            res = mThreadStartStopEvent.wait(mThreadStateMutex, THREAD_STOP_TIMEOUT*1000);
+            LOG(DEBUG) << "Thread " << mThreadName << " (" << this << ") signalled stop "
+                       << "with res=" << res << " and mThreadState=" << mThreadState;
+
+            // If the thread does not stop in THREAD_STOP_TIMEOUT seconds,
+            // return error. It may be waiting for something.
+            if (res == ETIMEDOUT)
+            {
+               LOG(ALERT) << "thread " << mThreadName << " (" << this << ") hasn't stopped in "
+                          << THREAD_STARTUP_TIMEOUT << " seconds. Bailing out.";
+
+               return RETURN_TIMEOUT;
+            }
+
+            // Conditional variable could return in case of a signal, so we should
+            // double check that the thread has indeed stopped.
+            if (mThreadState == THREAD_STATE_IDLE)
+                return RETURN_OK;
+            else
+                // Try again...
+                break;
+        }
+    }
+
+    // We should never reach this line
+    assert(false);
+    return RETURN_OK;
+}

 // vim: ts=4 sw=4
--- a/CommonLibs/Threads.h
+++ b/CommonLibs/Threads.h
@@ -1,5 +1,6 @@
 /*
 * Copyright 2008, 2011 Free Software Foundation, Inc.
+* Copyright 2013 Alexander Chemeris <Alexander.Chemeris@fairwaves.ru>
 *
 * This software is distributed under the terms of the GNU Affero Public License.
 * See the COPYING file in the main directory for details.
@@ -121,14 +122,14 @@ class Signal {
 		Block for the signal up to the cancellation timeout.
 		Under Linux, spurious returns are possible.
 	*/
-	void wait(Mutex& wMutex, unsigned timeout) const;
+	int wait(Mutex& wMutex, unsigned timeout) const;

 	/**
 		Block for the signal.
 		Under Linux, spurious returns are possible.
 	*/
-	void wait(Mutex& wMutex) const
-		{ pthread_cond_wait(&mSignal,&wMutex.mMutex); }
+	int wait(Mutex& wMutex) const
+		{ return pthread_cond_wait(&mSignal,&wMutex.mMutex); }

 	void signal() { pthread_cond_signal(&mSignal); }

@@ -137,47 +138,105 @@ class Signal {
 };


-
-#define START_THREAD(thread,function,argument) \
-	thread.start((void *(*)(void*))function, (void*)argument);
-
 /** A C++ wrapper for pthread threads.  */
 class Thread {

-	private:
+public:

-	pthread_t mThread;
-	pthread_attr_t mAttrib;
-	// FIXME -- Can this be reduced now?
-	size_t mStackSize;
-	
+    typedef void *(*Adaptor)(void*);
+    enum ReturnStatus {
+        RETURN_OK = 0,
+        ALREADY_STARTED,
+        ALREADY_IDLE,
+        PTHREAD_ERROR,
+        WRONG_STATE,
+        RETURN_TIMEOUT
+    };
+    enum ThreadState {
+        THREAD_STATE_IDLE,      ///< Thread is not started. On start() => STARTING
+        THREAD_STATE_STARTING,  ///< Thread is about to start. When actually started => RUNNING
+        THREAD_STATE_RUNNING,   ///< Thread is active. On stop() => STOPPING
+        THREAD_STATE_STOPPING   ///< Thread is about to stop. When actually stopped => IDLE
+    };
+    enum {
+       THREAD_STARTUP_TIMEOUT=5, ///< Time to wait for thread startup (in seconds).
+       THREAD_STOP_TIMEOUT=5     ///< Time to wait for thread stop (in seconds).
+    };

-	public:
+    /** Create a thread in a non-running state. */
+    Thread(const std::string &name, size_t stackSize = (65536*4));

-	/** Create a thread in a non-running state. */
-	Thread(size_t wStackSize = (65536*4)):mThread((pthread_t)0) {
-		pthread_attr_init(&mAttrib);	// (pat) moved this here.
-		mStackSize=wStackSize;
-	}
+    /** Destroy the Thread. */
+    virtual ~Thread();

-	/**
-		Destroy the Thread.
-		It should be stopped and joined.
-	*/
-	// (pat) If the Thread is destroyed without being started, then mAttrib is undefined.  Oops.
-	~Thread() { pthread_attr_destroy(&mAttrib); }
+    /** Start the thread. */
+    ReturnStatus startThread(void *data=NULL);

+    /** Stop the thread. */
+    ReturnStatus stopThread();

-	/** Start the thread on a task. */
-	void start(void *(*task)(void*), void *arg);
+    ThreadState getThreadState() const
+    {
+        ScopedLock lock(mThreadStateMutex);
+        return mThreadState;
+    }

-	/** Join a thread that will stop on its own. */
-	void join() { int s = pthread_join(mThread,NULL); assert(!s); mThread = 0; }
+    bool isThreadRunning() const
+    {
+        ScopedLock lock(mThreadStateMutex);
+        return mThreadState == THREAD_STATE_RUNNING;
+    }
+    void requestThreadStop()
+    {
+        ScopedLock lock(mThreadStateMutex);
+        if (mThreadState == THREAD_STATE_RUNNING)
+            mThreadState = THREAD_STATE_STOPPING;
+    }
+    bool isThreadStopping() const
+    {
+        ScopedLock lock(mThreadStateMutex);
+        return mThreadState == THREAD_STATE_STOPPING;
+    }

+    const std::string &getThreadName() const {return mThreadName;}
+
+protected:
+
+    pthread_t mThreadId; ///< OS id of the thread.
+    const std::string mThreadName; ///< Name of the thread.
+    size_t mStackSize;  ///< Requested stack size for the thread.
+    ThreadState mThreadState; ///< The current state of the thread.
+    mutable Mutex mThreadStateMutex; ///< Mutex to protect ThreadState variable
+    void *mThreadData;  ///< Data to be passed to the thread loop.
+    Mutex mThreadStartupMutex; ///< Mutex, used with the next two conditional
+                        ///< variables to synchronize thread startup.
+    Signal  mThreadInitializedEvent; ///< Conditional variable, signaling
+                        ///< that this thread object initialization is completed
+                        ///< and the thread could go on.
+    Signal  mThreadStartStopEvent; ///< Conditional variable, signaling
+                        ///< that the thread is started and start() method could
+                        ///< return to caller.
+
+    /** Function with the actual thread loop.
+     *  Override this function in child classes to do real work.
+     */
+    virtual void runThread() =0;
+
+    // Static funciton which actually starts the run() method.
+    static void *threadAdaptor(void *data);
+
+    void ackThreadStart() {
+        ScopedLock lock(mThreadStateMutex);
+        assert(mThreadState == THREAD_STATE_STARTING);
+        mThreadState = THREAD_STATE_RUNNING;
+    }
+    void ackThreadStop() {
+        ScopedLock lock(mThreadStateMutex);
+        assert(mThreadState == THREAD_STATE_STOPPING);
+        mThreadState = THREAD_STATE_IDLE;
+    }
 };


-
-
 #endif
 // vim: ts=4 sw=4
--- a/CommonLibs/ThreadsTest.cpp
+++ b/CommonLibs/ThreadsTest.cpp
@@ -0,0 +1,94 @@
+/*
+* Copyright 2013 Alexander Chemeris <Alexander.Chemeris@fairwaves.ru>
+*
+*
+* This software is distributed under the terms of the GNU Affero Public License.
+* See the COPYING file in the main directory for details.
+*
+* This use of this software may be subject to additional restrictions.
+* See the LEGAL file in the main directory for details.
+
+	This program is free software: you can redistribute it and/or modify
+	it under the terms of the GNU Affero General Public License as published by
+	the Free Software Foundation, either version 3 of the License, or
+	(at your option) any later version.
+
+	This program is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU Affero General Public License for more details.
+
+	You should have received a copy of the GNU Affero General Public License
+	along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+*/
+
+
+
+#include "Threads.h"
+#include "Timeval.h"
+#include "Configuration.h"
+#include <iostream>
+
+ConfigurationTable gConfig;
+
+class SimpleThreadTest : public Thread
+{
+public:
+    SimpleThreadTest() : Thread("SimpleThreadTest") {}
+
+    void runThread()
+    {
+        COUT(getThreadName() << ": Started thread");
+        while (isThreadRunning()) {
+            COUT(getThreadName() << ": Sleeping...");
+            msleep(50);
+        }
+        COUT(getThreadName() << ": Stopped thread");
+    }
+
+};
+
+
+void testSimpleStartStop()
+{
+    SimpleThreadTest simpleThreadTest;
+    COUT("Main: Starting thread " << simpleThreadTest.getThreadName());
+    simpleThreadTest.startThread();
+    COUT("Main: Started  thread " << simpleThreadTest.getThreadName());
+    msleep(30);
+    COUT("Main: Stopping thread " << simpleThreadTest.getThreadName());
+    simpleThreadTest.stopThread();
+    COUT("Main: Stopped  thread " << simpleThreadTest.getThreadName());
+}
+
+void testDoubleRequestStop()
+{
+    SimpleThreadTest simpleThreadTest;
+    COUT("Main: Starting thread " << simpleThreadTest.getThreadName());
+    simpleThreadTest.startThread();
+    COUT("Main: Started  thread " << simpleThreadTest.getThreadName());
+    msleep(30);
+    COUT("Main: Requesting stop for thread " << simpleThreadTest.getThreadName());
+    simpleThreadTest.requestThreadStop();
+    msleep(30);
+    COUT("Main: Requesting stop for thread " << simpleThreadTest.getThreadName());
+    simpleThreadTest.requestThreadStop();
+    msleep(30);
+    COUT("Main: Stopping thread " << simpleThreadTest.getThreadName());
+    simpleThreadTest.stopThread();
+    COUT("Main: Stopped  thread " << simpleThreadTest.getThreadName());
+}
+
+
+int main(int argc, char *argv[])
+{
+    std::cout<< std::endl << "Simple start/stop test" << std::endl << std::endl ;
+    testSimpleStartStop();
+
+    std::cout << std::endl << "Double requestThreadStop() test" << std::endl << std::endl ;
+    testDoubleRequestStop();
+}
+
+
+// vim: ts=4 sw=4
--- a/Makefile.common
+++ b/Makefile.common
@@ -18,18 +18,11 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #

-#hack to get around symlink svn:externals in git -kurtis
-top_srcdir = $(abs_top_srcdir)
-top_builddir = $(abs_top_builddir)
-
 COMMON_INCLUDEDIR = $(top_srcdir)/CommonLibs
 GSM_INCLUDEDIR = $(top_srcdir)/GSM
 SQLITE_INCLUDEDIR = $(top_srcdir)/sqlite3

-SVNDEV = -D'SVN_REV="$(shell svnversion -n $(top_builddir))"'
-
 STD_DEFINES_AND_INCLUDES = \
-	$(SVNDEV) \
 	-I$(COMMON_INCLUDEDIR) \
 	-I$(GSM_INCLUDEDIR) \
 	-I$(SQLITE_INCLUDEDIR)
--- a/Transceiver52M/DriveLoop.cpp
+++ b/Transceiver52M/DriveLoop.cpp
@@ -0,0 +1,268 @@
+/*
+* Copyright 2008, 2009, 2010, 2012 Free Software Foundation, Inc.
+* Copyright 2013 Alexander Chemeris <Alexander.Chemeris@fairwaves.ru>
+*
+* This software is distributed under the terms of the GNU Public License.
+* See the COPYING file in the main directory for details.
+*
+* This use of this software may be subject to additional restrictions.
+* See the LEGAL file in the main directory for details.
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include <stdio.h>
+#include "DriveLoop.h"
+#include <Logger.h>
+
+using namespace GSM;
+
+DriveLoop::DriveLoop(int wBasePort, const char *TRXAddress,
+                     RadioInterface *wRadioInterface,
+		     int wChanM, int wC0, int wSamplesPerSymbol,
+                     GSM::Time wTransmitLatency)
+: Thread("DriveLoop")
+, mClockSocket(wBasePort, TRXAddress, wBasePort + 100)
+, mC0(wC0)
+{
+  mChanM = wChanM;
+  mSamplesPerSymbol = wSamplesPerSymbol;
+  mRadioInterface = wRadioInterface;
+
+  mStartTime = (random() % gHyperframe, 0);
+
+  mTransmitDeadlineClock = mStartTime;
+  mLatencyUpdateTime = mStartTime;
+  mTransmitLatency = wTransmitLatency;
+  mLastClockUpdateTime = mStartTime;
+
+  mRadioInterface->getClock()->set(mStartTime);
+
+  // generate pulse and setup up signal processing library
+  gsmPulse = generateGSMPulse(2, mSamplesPerSymbol);
+  LOG(DEBUG) << "gsmPulse: " << *gsmPulse;
+  sigProcLibSetup(mSamplesPerSymbol);
+
+  txFullScale = mRadioInterface->fullScaleInputValue();
+
+  // initialize filler tables with dummy bursts on C0, empty bursts otherwise
+  for (int i = 0; i < 8; i++) {
+    signalVector* modBurst = modulateBurst(gDummyBurst, *gsmPulse,
+                                           8 + (i % 4 == 0), mSamplesPerSymbol);
+    scaleVector(*modBurst, txFullScale);
+    for (int j = 0; j < 102; j++) {
+      for (int n = 0; n < mChanM; n++) {
+        if (n == mC0)
+          fillerTable[n][j][i] = new signalVector(*modBurst);
+        else
+          fillerTable[n][j][i] = new signalVector(modBurst->size());
+      }
+    }
+    delete modBurst;
+
+    for (int n = 0; n < mChanM; n++) {
+      fillerModulus[n][i] = 26;
+      mChanType[n][i] = NONE;
+    }
+  }
+}
+
+DriveLoop::~DriveLoop()
+{
+  stopThread();
+  delete gsmPulse;
+  sigProcLibDestroy();
+}
+
+void DriveLoop::pushRadioVector(GSM::Time &nowTime)
+{
+  int i;
+  radioVector *staleBurst;
+  radioVector *next;
+
+  for (i = 0; i < mChanM; i++) {
+    // dump stale bursts, if any
+    while (staleBurst = mTransmitPriorityQueue[i].getStaleBurst(nowTime)) {
+      // Even if the burst is stale, put it in the fillter table.
+      // (It might be an idle pattern.)
+      LOG(NOTICE) << "dumping STALE burst in TRX->USRP interface";
+    }
+
+    int TN = nowTime.TN();
+    int modFN = nowTime.FN() % fillerModulus[i][nowTime.TN()];
+
+    mTxBursts[i] = fillerTable[i][modFN][TN];
+    mIsFiller[i] = true;
+    mIsZero[i] = (mChanType[i][TN] == NONE);
+
+    // if queue contains data at the desired timestamp, stick it into FIFO
+    if (next = (radioVector*) mTransmitPriorityQueue[i].getCurrentBurst(nowTime)) {
+      LOG(DEBUG) << "transmitFIFO: wrote burst " << next << " at time: " << nowTime;
+      mTxBursts[i] = next;
+      mIsFiller[i] = false;
+      mIsZero[i] = false;
+    }
+  }
+
+  mRadioInterface->driveTransmitRadio(mTxBursts, mIsZero);
+
+  for (i = 0; i < mChanM; i++) {
+    if (!mIsFiller[i])
+      delete mTxBursts[i];
+  }
+}
+
+void DriveLoop::setModulus(int channel, int timeslot)
+{
+  switch (mChanType[channel][timeslot]) {
+  case NONE:
+  case I:
+  case II:
+  case III:
+  case FILL:
+    fillerModulus[channel][timeslot] = 26;
+    break;
+  case IV:
+  case VI:
+  case V:
+    fillerModulus[channel][timeslot] = 51;
+    break;
+    //case V: 
+  case VII:
+    fillerModulus[channel][timeslot] = 102;
+    break;
+  default:
+    break;
+  }
+}
+
+DriveLoop::CorrType DriveLoop::expectedCorrType(int channel, GSM::Time currTime)
+{
+  unsigned burstTN = currTime.TN();
+  unsigned burstFN = currTime.FN();
+
+  switch (mChanType[channel][burstTN]) {
+  case NONE:
+    return OFF;
+    break;
+  case FILL:
+    return IDLE;
+    break;
+  case I:
+    return TSC;
+    /*if (burstFN % 26 == 25) 
+      return IDLE;
+    else
+      return TSC;*/
+    break;
+  case II:
+    if (burstFN % 2 == 1)
+      return IDLE;
+    else
+      return TSC;
+    break;
+  case III:
+    return TSC;
+    break;
+  case IV:
+  case VI:
+    return RACH;
+    break;
+  case V: {
+    int mod51 = burstFN % 51;
+    if ((mod51 <= 36) && (mod51 >= 14))
+      return RACH;
+    else if ((mod51 == 4) || (mod51 == 5))
+      return RACH;
+    else if ((mod51 == 45) || (mod51 == 46))
+      return RACH;
+    else
+      return TSC;
+    break;
+  }
+  case VII:
+    if ((burstFN % 51 <= 14) && (burstFN % 51 >= 12))
+      return IDLE;
+    else
+      return TSC;
+    break;
+  case LOOPBACK:
+    if ((burstFN % 51 <= 50) && (burstFN % 51 >=48))
+      return IDLE;
+    else
+      return TSC;
+    break;
+  default:
+    return OFF;
+    break;
+  }
+}
+ 
+void DriveLoop::driveReceiveFIFO() 
+{
+  SoftVector *rxBurst = NULL;
+  int RSSI;
+  int TOA;  // in 1/256 of a symbol
+  GSM::Time burstTime;
+
+  mRadioInterface->driveReceiveRadio();
+}
+
+/*
+ *  Features a carefully controlled latency mechanism, to
+ *  assure that transmit packets arrive at the radio/USRP
+ *  before they need to be transmitted.
+ *  
+ *  Deadline clock indicates the burst that needs to be
+ *  pushed into the FIFO right NOW.  If transmit queue does
+ *  not have a burst, stick in filler data.
+ */
+void DriveLoop::driveTransmitFIFO() 
+{
+  int i;
+
+  RadioClock *radioClock = (mRadioInterface->getClock());
+  while (radioClock->get() + mTransmitLatency > mTransmitDeadlineClock) {
+    pushRadioVector(mTransmitDeadlineClock);
+    mTransmitDeadlineClock.incTN();
+  }
+
+  // FIXME -- This should not be a hard spin.
+  // But any delay here causes us to throw omni_thread_fatal.
+  //else radioClock->wait();
+}
+
+void DriveLoop::writeClockInterface()
+{
+  char command[50];
+  // FIXME -- This should be adaptive.
+  sprintf(command,"IND CLOCK %llu",
+          (unsigned long long) (mTransmitDeadlineClock.FN() + 2));
+
+  LOG(INFO) << "ClockInterface: sending " << command;
+
+  mClockSocket.write(command,strlen(command)+1);
+
+  mLastClockUpdateTime = mTransmitDeadlineClock;
+}
+
+void DriveLoop::runThread()
+{
+  setPriority();
+
+  while (isThreadRunning()) {
+    driveReceiveFIFO();
+    driveTransmitFIFO();
+  }
+}
--- a/Transceiver52M/DriveLoop.h
+++ b/Transceiver52M/DriveLoop.h
@@ -0,0 +1,188 @@
+/*
+* Copyright 2008, 2012 Free Software Foundation, Inc.
+* Copyright 2013 Alexander Chemeris <Alexander.Chemeris@fairwaves.ru>
+*
+* This software is distributed under the terms of the GNU Public License.
+* See the COPYING file in the main directory for details.
+*
+* This use of this software may be subject to additional restrictions.
+* See the LEGAL file in the main directory for details.
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+*/
+
+
+
+/*
+	Compilation switches
+	TRANSMIT_LOGGING	write every burst on the given slot to a log
+*/
+
+#ifndef _DRIVELOOP_H_
+#define _DRIVELOOP_H_
+
+#include "radioInterface.h"
+#include "Interthread.h"
+#include "GSMCommon.h"
+#include "Sockets.h"
+
+#include <sys/types.h>
+#include <sys/socket.h>
+
+/** Define this to be the slot number to be logged. */
+//#define TRANSMIT_LOGGING 1
+
+/** The Transceiver class, responsible for physical layer of basestation */
+class DriveLoop : public Thread {
+  
+private:
+
+  GSM::Time mTransmitLatency;     ///< latency between basestation clock and transmit deadline clock
+  GSM::Time mLatencyUpdateTime;   ///< last time latency was updated
+  GSM::Time mLastClockUpdateTime; ///< last time clock update was sent up to core
+
+  UDPSocket mClockSocket;	  ///< socket for writing clock updates to GSM core
+
+  VectorQueue  mTransmitPriorityQueue[CHAN_MAX];   ///< priority queue of transmit bursts received from GSM core
+
+  GSM::Time mTransmitDeadlineClock;       ///< deadline for pushing bursts into transmit FIFO 
+  GSM::Time mStartTime;                   ///< random start time of the radio clock
+
+  RadioInterface *mRadioInterface;	  ///< associated radioInterface object
+  double txFullScale;                     ///< full scale input to radio
+  double rxFullScale;                     ///< full scale output to radio
+
+  /** Number of channels supported by the channelizer */
+  int mChanM;
+
+  /** unmodulate a modulated burst */
+#ifdef TRANSMIT_LOGGING
+  void unModulateVector(signalVector wVector); 
+#endif
+
+  /** Push modulated burst into transmit FIFO corresponding to a particular timestamp */
+  void pushRadioVector(GSM::Time &nowTime);
+
+  /** Pull and demodulate a burst from the receive FIFO */ 
+  SoftVector *pullRadioVector(GSM::Time &wTime, int &RSSI, int &timingOffset);
+   
+  signalVector *gsmPulse;              ///< the GSM shaping pulse for modulation
+
+  int mSamplesPerSymbol;               ///< number of samples per GSM symbol
+
+  int fillerModulus[CHAN_MAX][8];                ///< modulus values of all timeslots, in frames
+  signalVector *fillerTable[CHAN_MAX][102][8];   ///< table of modulated filler waveforms for all timeslots
+
+  /** Channelizer path for primary ARFCN */
+  int mC0;
+
+  signalVector *mTxBursts[CHAN_MAX];
+  bool         mIsFiller[CHAN_MAX];
+  bool         mIsZero[CHAN_MAX];
+
+public:
+
+  /** Transceiver constructor 
+      @param wBasePort base port number of UDP sockets
+      @param TRXAddress IP address of the TRX manager, as a string
+      @param wSamplesPerSymbol number of samples per GSM symbol
+      @param wTransmitLatency initial setting of transmit latency
+      @param radioInterface associated radioInterface object
+  */
+  DriveLoop(int wBasePort, const char *TRXAddress,
+	    RadioInterface *wRadioInterface,
+	    int wChanM = 1, int wC0 = 0,
+            int wSamplesPerSymbol = SAMPSPERSYM,
+	    GSM::Time wTransmitLatency = GSM::Time(3, 0));
+   
+  /** Destructor */
+  ~DriveLoop();
+
+  VectorQueue *priorityQueue(int m) { return &mTransmitPriorityQueue[m]; }
+
+  /** Codes for burst types of received bursts*/
+  typedef enum {
+    OFF,               ///< timeslot is off
+    TSC,	       ///< timeslot should contain a normal burst
+    RACH,	       ///< timeslot should contain an access burst
+    IDLE	       ///< timeslot is an idle (or dummy) burst
+  } CorrType;
+
+  /** Codes for channel combinations */
+  typedef enum {
+    FILL,               ///< Channel is transmitted, but unused
+    I,                  ///< TCH/FS
+    II,                 ///< TCH/HS, idle every other slot
+    III,                ///< TCH/HS
+    IV,                 ///< FCCH+SCH+CCCH+BCCH, uplink RACH
+    V,                  ///< FCCH+SCH+CCCH+BCCH+SDCCH/4+SACCH/4, uplink RACH+SDCCH/4
+    VI,                 ///< CCCH+BCCH, uplink RACH
+    VII,                ///< SDCCH/8 + SACCH/8
+    NONE,               ///< Channel is inactive, default
+    LOOPBACK            ///< similar go VII, used in loopback testing
+  } ChannelCombination;
+
+  /** Set modulus for specific timeslot */
+  void setModulus(int channel, int timeslot);
+
+  /** return the expected burst type for the specified timestamp */
+  CorrType expectedCorrType(int channel, GSM::Time currTime);
+
+  void setTimeslot(int m, int timeslot, ChannelCombination comb)
+  {
+    mChanType[m][timeslot] = comb;
+  }
+
+  GSM::Time getStartTime() { return mStartTime; }
+  GSM::Time getLastClockUpdate() { return mLastClockUpdateTime; }
+  GSM::Time getDeadlineClock() { return mTransmitDeadlineClock; }
+
+  /** send messages over the clock socket */
+  void writeClockInterface(void);
+
+private:
+
+  ChannelCombination mChanType[CHAN_MAX][8];     ///< channel types for all timeslots
+
+protected:
+
+  /** drive reception and demodulation of GSM bursts */ 
+  void driveReceiveFIFO();
+
+  /** drive transmission of GSM bursts */
+  void driveTransmitFIFO();
+
+  /** drive handling of control messages from GSM core */
+  void driveControl();
+
+  /**
+    drive modulation and sorting of GSM bursts from GSM core
+    @return true if a burst was transferred successfully
+  */
+  bool driveTransmitPriorityQueue();
+
+  virtual void runThread();
+
+  void reset();
+
+  /** set priority on current thread */
+  void setPriority() { mRadioInterface->setPriority(); }
+
+};
+
+/** FIFO thread loop */
+void *RadioDriveLoopAdapter(DriveLoop *);
+
+#endif /* _DRIVELOOP_H_ */
--- a/Transceiver52M/Makefile.am
+++ b/Transceiver52M/Makefile.am
@@ -52,21 +52,14 @@ COMMON_SOURCES = \
 	radioVector.cpp \
 	radioClock.cpp \
 	sigProcLib.cpp \
+	DriveLoop.cpp \
 	Transceiver.cpp \
 	DummyLoad.cpp

-if RESAMPLE
 libtransceiver_la_SOURCES = \
-	$(COMMON_SOURCES) \
-	radioIOResamp.cpp
-else
-libtransceiver_la_SOURCES = \
-	$(COMMON_SOURCES) \
-	radioIO.cpp
-endif
+	$(COMMON_SOURCES)

 noinst_PROGRAMS = \
-	USRPping \
 	transceiver \
 	sigProcLibTest 

@@ -83,12 +76,7 @@ noinst_HEADERS = \
 	rcvLPF_651.h \
 	sendLPF_961.h

-USRPping_SOURCES = USRPping.cpp
-USRPping_LDADD = \
-	libtransceiver.la \
-	$(COMMON_LA) $(SQLITE_LA)
-
-transceiver_SOURCES = runTransceiver.cpp
+transceiver_SOURCES = multiTRX.cpp
 transceiver_LDADD = \
 	libtransceiver.la \
 	$(GSM_LA) \
@@ -104,13 +92,11 @@ sigProcLibTest_LDADD = \
 if UHD
 libtransceiver_la_SOURCES += UHDDevice.cpp
 transceiver_LDADD += $(UHD_LIBS)
-USRPping_LDADD += $(UHD_LIBS)
 sigProcLibTest_LDADD += $(UHD_LIBS)
 else
 if USRP1
 libtransceiver_la_SOURCES += USRPDevice.cpp
 transceiver_LDADD += $(USRP_LIBS)
-USRPping_LDADD += $(USRP_LIBS)
 sigProcLibTest_LDADD += $(USRP_LIBS)
 else
 #we should never be here, as one of the above mustbe defined for us to build
--- a/Transceiver52M/Transceiver.cpp
+++ b/Transceiver52M/Transceiver.cpp
@@ -1,5 +1,6 @@
 /*
-* Copyright 2008, 2009, 2010 Free Software Foundation, Inc.
+* Copyright 2008, 2009, 2010, 2012 Free Software Foundation, Inc.
+* Copyright 2013 Alexander Chemeris <Alexander.Chemeris@fairwaves.ru>
 *
 * This software is distributed under the terms of the GNU Public License.
 * See the COPYING file in the main directory for details.
@@ -48,72 +49,57 @@ using namespace GSM;

 #define INIT_ENERGY_THRSHD		5.0f

-Transceiver::Transceiver(int wBasePort,
-			 const char *TRXAddress,
-			 int wSamplesPerSymbol,
-			 GSM::Time wTransmitLatency,
-			 RadioInterface *wRadioInterface)
-	:mDataSocket(wBasePort+2,TRXAddress,wBasePort+102),
+Transceiver::Transceiver(int wBasePort, const char *TRXAddress,
+			 DriveLoop *wDriveLoop, RadioInterface *wRadioInterface,
+			 int wSamplesPerSymbol, int wChannel, bool wPrimary)
+	:mBasePort(wBasePort), mTRXAddress(TRXAddress),
+	 mDataSocket(wBasePort+2,TRXAddress,wBasePort+102),
 	 mControlSocket(wBasePort+1,TRXAddress,wBasePort+101),
-	 mClockSocket(wBasePort,TRXAddress,wBasePort+100)
+	 mDriveLoop(wDriveLoop), mRadioInterface(wRadioInterface),
+	 mSamplesPerSymbol(wSamplesPerSymbol), mTransmitPriorityQueue(NULL),
+	 mChannel(wChannel), mPrimary(wPrimary)
 {
-  //GSM::Time startTime(0,0);
-  //GSM::Time startTime(gHyperframe/2 - 4*216*60,0);
-  GSM::Time startTime(random() % gHyperframe,0);
-
-  mFIFOServiceLoopThread = new Thread(32768);  ///< thread to push bursts into transmit FIFO
-  mControlServiceLoopThread = new Thread(32768);       ///< thread to process control messages from GSM core
-  mTransmitPriorityQueueServiceLoopThread = new Thread(32768);///< thread to process transmit bursts from GSM core
-
-
-  mSamplesPerSymbol = wSamplesPerSymbol;
-  mRadioInterface = wRadioInterface;
-  mTransmitLatency = wTransmitLatency;
-  mTransmitDeadlineClock = startTime;
-  mLastClockUpdateTime = startTime;
-  mLatencyUpdateTime = startTime;
-  mRadioInterface->getClock()->set(startTime);
  mMaxExpectedDelay = 0;

  // generate pulse and setup up signal processing library
  gsmPulse = generateGSMPulse(2,mSamplesPerSymbol);
  LOG(DEBUG) << "gsmPulse: " << *gsmPulse;
-  sigProcLibSetup(mSamplesPerSymbol);
+
+  mTransmitPriorityQueue = mDriveLoop->priorityQueue(mChannel);
+  mReceiveFIFO = mRadioInterface->receiveFIFO(mChannel);

  txFullScale = mRadioInterface->fullScaleInputValue();
  rxFullScale = mRadioInterface->fullScaleOutputValue();

-  // initialize filler tables with dummy bursts, initialize other per-timeslot variables
+  // initialize per-timeslot variables
  for (int i = 0; i < 8; i++) {
-    signalVector* modBurst = modulateBurst(gDummyBurst,*gsmPulse,
-					   8 + (i % 4 == 0),
-					   mSamplesPerSymbol);
-    scaleVector(*modBurst,txFullScale);
-    fillerModulus[i]=26;
-    for (int j = 0; j < 102; j++) {
-      fillerTable[j][i] = new signalVector(*modBurst);
-    }
-    delete modBurst;
-    mChanType[i] = NONE;
    channelResponse[i] = NULL;
    DFEForward[i] = NULL;
    DFEFeedback[i] = NULL;
-    channelEstimateTime[i] = startTime;
+    channelEstimateTime[i] = mDriveLoop->getStartTime();
  }

  mOn = false;
+  mRunning = false;
  mTxFreq = 0.0;
  mRxFreq = 0.0;
+  mFreqOffset = 0.0;
+
  mPower = -10;
  mEnergyThreshold = INIT_ENERGY_THRSHD;
-  prevFalseDetectionTime = startTime;
+  prevFalseDetectionTime = mDriveLoop->getStartTime();
 }

 Transceiver::~Transceiver()
 {
+  // Stop all threads before freeing up
+  mFIFOServiceLoop.shutdown();
+  mControlServiceLoop.shutdown();
+  mTransmitPriorityQueueServiceLoop.shutdown();
+
+  // Now free all allocated data
  delete gsmPulse;
-  sigProcLibDestroy();
-  mTransmitPriorityQueue.clear();
+  mTransmitPriorityQueue->clear();
 }
  

@@ -127,182 +113,18 @@ void Transceiver::addRadioVector(BitVector &burst,
 					 mSamplesPerSymbol);
  scaleVector(*modBurst,txFullScale * pow(10,-RSSI/10));
  radioVector *newVec = new radioVector(*modBurst,wTime);
-  mTransmitPriorityQueue.write(newVec);
+  mTransmitPriorityQueue->write(newVec);

  delete modBurst;
 }

-#ifdef TRANSMIT_LOGGING
-void Transceiver::unModulateVector(signalVector wVector) 
-{
-  SoftVector *burst = demodulateBurst(wVector,
-				   *gsmPulse,
-				   mSamplesPerSymbol,
-				   1.0,0.0);
-  LOG(DEBUG) << "LOGGED BURST: " << *burst;
-
-/*
-  unsigned char burstStr[gSlotLen+1];
-  SoftVector::iterator burstItr = burst->begin();
-  for (int i = 0; i < gSlotLen; i++) {
-    // FIXME: Demod bits are inverted!
-    burstStr[i] = (unsigned char) ((*burstItr++)*255.0);
-  }
-  burstStr[gSlotLen]='\0';
-  LOG(DEBUG) << "LOGGED BURST: " << burstStr;
-*/
-  delete burst;
-}
-#endif
-
-void Transceiver::pushRadioVector(GSM::Time &nowTime)
-{
-
-  // dump stale bursts, if any
-  while (radioVector* staleBurst = mTransmitPriorityQueue.getStaleBurst(nowTime)) {
-    // Even if the burst is stale, put it in the fillter table.
-    // (It might be an idle pattern.)
-    LOG(NOTICE) << "dumping STALE burst in TRX->USRP interface";
-    const GSM::Time& nextTime = staleBurst->getTime();
-    int TN = nextTime.TN();
-    int modFN = nextTime.FN() % fillerModulus[TN];
-    delete fillerTable[modFN][TN];
-    fillerTable[modFN][TN] = staleBurst;
-  }
-  
-  int TN = nowTime.TN();
-  int modFN = nowTime.FN() % fillerModulus[nowTime.TN()];
-
-  // if queue contains data at the desired timestamp, stick it into FIFO
-  if (radioVector *next = (radioVector*) mTransmitPriorityQueue.getCurrentBurst(nowTime)) {
-    LOG(DEBUG) << "transmitFIFO: wrote burst " << next << " at time: " << nowTime;
-    delete fillerTable[modFN][TN];
-    fillerTable[modFN][TN] = new signalVector(*(next));
-    mRadioInterface->driveTransmitRadio(*(next),(mChanType[TN]==NONE)); //fillerTable[modFN][TN]));
-    delete next;
-#ifdef TRANSMIT_LOGGING
-    if (nowTime.TN()==TRANSMIT_LOGGING) { 
-      unModulateVector(*(fillerTable[modFN][TN]));
-    }
-#endif
-    return;
-  }
-
-  // otherwise, pull filler data, and push to radio FIFO
-  mRadioInterface->driveTransmitRadio(*(fillerTable[modFN][TN]),(mChanType[TN]==NONE));
-#ifdef TRANSMIT_LOGGING
-  if (nowTime.TN()==TRANSMIT_LOGGING) 
-    unModulateVector(*fillerTable[modFN][TN]);
-#endif
-
-}
-
-void Transceiver::setModulus(int timeslot)
-{
-  switch (mChanType[timeslot]) {
-  case NONE:
-  case I:
-  case II:
-  case III:
-  case FILL:
-    fillerModulus[timeslot] = 26;
-    break;
-  case IV:
-  case VI:
-  case V:
-    fillerModulus[timeslot] = 51;
-    break;
-    //case V: 
-  case VII:
-    fillerModulus[timeslot] = 102;
-    break;
-  case XIII:
-    fillerModulus[timeslot] = 52;
-    break;
-  default:
-    break;
-  }
-}
-
-
-Transceiver::CorrType Transceiver::expectedCorrType(GSM::Time currTime)
-{
-  
-  unsigned burstTN = currTime.TN();
-  unsigned burstFN = currTime.FN();
-
-  switch (mChanType[burstTN]) {
-  case NONE:
-    return OFF;
-    break;
-  case FILL:
-    return IDLE;
-    break;
-  case I:
-    return TSC;
-    /*if (burstFN % 26 == 25) 
-      return IDLE;
-    else
-      return TSC;*/
-    break;
-  case II:
-    return TSC;
-    break;
-  case III:
-    return TSC;
-    break;
-  case IV:
-  case VI:
-    return RACH;
-    break;
-  case V: {
-    int mod51 = burstFN % 51;
-    if ((mod51 <= 36) && (mod51 >= 14))
-      return RACH;
-    else if ((mod51 == 4) || (mod51 == 5))
-      return RACH;
-    else if ((mod51 == 45) || (mod51 == 46))
-      return RACH;
-    else
-      return TSC;
-    break;
-  }
-  case VII:
-    if ((burstFN % 51 <= 14) && (burstFN % 51 >= 12))
-      return IDLE;
-    else
-      return TSC;
-    break;
-  case XIII: {
-    int mod52 = burstFN % 52;
-    if ((mod52 == 12) || (mod52 == 38))
-      return RACH;
-    else if ((mod52 == 25) || (mod52 == 51))
-      return IDLE;
-    else
-      return TSC;
-    break;
-  }
-  case LOOPBACK:
-    if ((burstFN % 51 <= 50) && (burstFN % 51 >=48))
-      return IDLE;
-    else
-      return TSC;
-    break;
-  default:
-    return OFF;
-    break;
-  }
-
-}
-    
 SoftVector *Transceiver::pullRadioVector(GSM::Time &wTime,
 				      int &RSSI,
 				      int &timingOffset)
 {
  bool needDFE = (mMaxExpectedDelay > 1);

-  radioVector *rxBurst = (radioVector *) mReceiveFIFO->get();
+  radioVector *rxBurst = (radioVector *) mReceiveFIFO->read();

  if (!rxBurst) return NULL;

@@ -310,9 +132,9 @@ SoftVector *Transceiver::pullRadioVector(GSM::Time &wTime,

  int timeslot = rxBurst->getTime().TN();

-  CorrType corrType = expectedCorrType(rxBurst->getTime());
+  DriveLoop::CorrType corrType = mDriveLoop->expectedCorrType(mChannel, rxBurst->getTime());

-  if ((corrType==OFF) || (corrType==IDLE)) {
+  if ((corrType == DriveLoop::OFF) || (corrType == DriveLoop::IDLE)) {
    delete rxBurst;
    return NULL;
  }
@@ -322,6 +144,7 @@ SoftVector *Transceiver::pullRadioVector(GSM::Time &wTime,
  complex amplitude = 0.0;
  float TOA = 0.0;
  float avgPwr = 0.0;
+
  if (!energyDetect(*vectorBurst,20*mSamplesPerSymbol,mEnergyThreshold,&avgPwr)) {
     LOG(DEBUG) << "Estimated Energy: " << sqrt(avgPwr) << ", at time " << rxBurst->getTime();
     double framesElapsed = rxBurst->getTime()-prevFalseDetectionTime;
@@ -339,8 +162,9 @@ SoftVector *Transceiver::pullRadioVector(GSM::Time &wTime,

  // run the proper correlator
  bool success = false;
-  if (corrType==TSC) {
+  if (corrType == DriveLoop::TSC) {
    LOG(DEBUG) << "looking for TSC at time: " << rxBurst->getTime();
+
    signalVector *channelResp;
    double framesElapsed = rxBurst->getTime()-channelEstimateTime[timeslot];
    bool estimateChannel = false;
@@ -413,7 +237,7 @@ SoftVector *Transceiver::pullRadioVector(GSM::Time &wTime,
  // demodulate burst
  SoftVector *burst = NULL;
  if ((rxBurst) && (success)) {
-    if ((corrType==RACH) || (!needDFE)) {
+    if ((corrType == DriveLoop::RACH) || (!needDFE)) {
      burst = demodulateBurst(*vectorBurst,
 			      *gsmPulse,
 			      mSamplesPerSymbol,
@@ -440,16 +264,68 @@ SoftVector *Transceiver::pullRadioVector(GSM::Time &wTime,
  return burst;
 }

+void Transceiver::pullFIFO()
+{
+  SoftVector *rxBurst = NULL;
+  int RSSI;
+  int TOA;  // in 1/256 of a symbol
+  GSM::Time burstTime;
+
+  rxBurst = pullRadioVector(burstTime,RSSI,TOA);
+
+  if (rxBurst) {
+    LOG(DEBUG) << "burst parameters: "
+               << " time: " << burstTime
+               << " RSSI: " << RSSI
+               << " TOA: "  << TOA
+               << " bits: " << *rxBurst;
+
+    char burstString[gSlotLen+10];
+    burstString[0] = burstTime.TN();
+    for (int i = 0; i < 4; i++) {
+            burstString[1+i] = (burstTime.FN() >> ((3-i)*8)) & 0x0ff;
+    }
+
+    burstString[5] = RSSI;
+    burstString[6] = (TOA >> 8) & 0x0ff;
+    burstString[7] = TOA & 0x0ff;
+    SoftVector::iterator burstItr = rxBurst->begin();
+
+    for (unsigned int i = 0; i < gSlotLen; i++) {
+            burstString[8+i] =(char) round((*burstItr++)*255.0);
+    }
+
+    burstString[gSlotLen+9] = '\0';
+    delete rxBurst;
+
+    mDataSocket.write(burstString,gSlotLen+10);
+  }
+}
+
 void Transceiver::start()
 {
-  mControlServiceLoopThread->start((void * (*)(void*))ControlServiceLoopAdapter,(void*) this);
+  mRunning = true;
+  mControlServiceLoop.startThread((void*) this);
+
+  if (!mPrimary) {
+    mOn = true;
+    mFIFOServiceLoop.startThread((void*) this);
+    mTransmitPriorityQueueServiceLoop.startThread((void*) this);
+  }
+}
+
+void Transceiver::shutdown()
+{
+  mOn = false;
+  mRunning = false;
+  mControlServiceLoop.shutdown();
+  mFIFOServiceLoop.shutdown();
+  mTransmitPriorityQueueServiceLoop.shutdown();
 }

 void Transceiver::reset()
 {
-  mTransmitPriorityQueue.clear();
-  //mTransmitFIFO->clear();
-  //mReceiveFIFO->clear();
+  mTransmitPriorityQueue->clear();
 }

  
@@ -462,10 +338,19 @@ void Transceiver::driveControl()
  char buffer[MAX_PACKET_LENGTH];
  int msgLen = -1;
  buffer[0] = '\0';
- 
-  msgLen = mControlSocket.read(buffer);

-  if (msgLen < 1) {
+  try { 
+    msgLen = mControlSocket.read(buffer);
+    if (msgLen < 1) {
+      return;
+    }
+  } catch (...) {
+    /* Ignore the read exception on shutdown */
+    if (!mRunning) {
+      return;
+    }
+
+    LOG(ALERT) << "Caught UHD socket exception";
    return;
  }

@@ -474,8 +359,8 @@ void Transceiver::driveControl()
  char response[MAX_PACKET_LENGTH];

  sscanf(buffer,"%3s %s",cmdcheck,command);
- 
-  writeClockInterface();
+
+  mDriveLoop->writeClockInterface();

  if (strcmp(cmdcheck,"CMD")!=0) {
    LOG(WARNING) << "bogus message on control interface";
@@ -489,22 +374,23 @@ void Transceiver::driveControl()
  }
  else if (strcmp(command,"POWERON")==0) {
    // turn on transmitter/demod
-    if (!mTxFreq || !mRxFreq) 
+    if (!mTxFreq || !mRxFreq || (mTSC<0))
      sprintf(response,"RSP POWERON 1");
    else {
      sprintf(response,"RSP POWERON 0");
-      if (!mOn) {
+      if (mPrimary && !mOn) {
        // Prepare for thread start
        mPower = -20;
        mRadioInterface->start();
+        mDriveLoop->startThread();
+
+        mDriveLoop->writeClockInterface();
        generateRACHSequence(*gsmPulse,mSamplesPerSymbol);

        // Start radio interface threads.
-        mFIFOServiceLoopThread->start((void * (*)(void*))FIFOServiceLoopAdapter,(void*) this);
-        mTransmitPriorityQueueServiceLoopThread->start((void * (*)(void*))TransmitPriorityQueueServiceLoopAdapter,(void*) this);
-        writeClockInterface();
-
        mOn = true;
+        mFIFOServiceLoop.startThread((void*) this);
+        mTransmitPriorityQueueServiceLoop.startThread((void*) this);
      }
    }
  }
@@ -519,8 +405,8 @@ void Transceiver::driveControl()
    //set expected maximum time-of-arrival
    int newGain;
    sscanf(buffer,"%3s %s %d",cmdcheck,command,&newGain);
-    newGain = mRadioInterface->setRxGain(newGain);
    mEnergyThreshold = INIT_ENERGY_THRSHD;
+    newGain = mRadioInterface->setRxGain(newGain, mChannel);
    sprintf(response,"RSP SETRXGAIN 0 %d",newGain);
  }
  else if (strcmp(command,"NOISELEV")==0) {
@@ -540,7 +426,7 @@ void Transceiver::driveControl()
      sprintf(response,"RSP SETPOWER 1 %d",dbPwr);
    else {
      mPower = dbPwr;
-      mRadioInterface->setPowerAttenuation(dbPwr);
+      mRadioInterface->setPowerAttenuation(dbPwr, mChannel);
      sprintf(response,"RSP SETPOWER 0 %d",dbPwr);
    }
  }
@@ -555,37 +441,36 @@ void Transceiver::driveControl()
      sprintf(response,"RSP ADJPOWER 0 %d",mPower);
    }
  }
-#define FREQOFFSET 0//11.2e3
  else if (strcmp(command,"RXTUNE")==0) {
    // tune receiver
    int freqKhz;
    sscanf(buffer,"%3s %s %d",cmdcheck,command,&freqKhz);
-    mRxFreq = freqKhz*1.0e3+FREQOFFSET;
-    if (!mRadioInterface->tuneRx(mRxFreq)) {
-       LOG(ALERT) << "RX failed to tune";
-       sprintf(response,"RSP RXTUNE 1 %d",freqKhz);
+    mRxFreq = freqKhz * 1.0e3 + mFreqOffset;
+    if (!mRadioInterface->tuneRx(mRxFreq, mChannel)) {
+      LOG(ALERT) << "RX failed to tune";
+      sprintf(response,"RSP RXTUNE 1 %d",freqKhz);
+    } else {
+      sprintf(response,"RSP RXTUNE 0 %d",freqKhz);
    }
-    else
-       sprintf(response,"RSP RXTUNE 0 %d",freqKhz);
  }
  else if (strcmp(command,"TXTUNE")==0) {
    // tune txmtr
    int freqKhz;
    sscanf(buffer,"%3s %s %d",cmdcheck,command,&freqKhz);
    //freqKhz = 890e3;
-    mTxFreq = freqKhz*1.0e3+FREQOFFSET;
-    if (!mRadioInterface->tuneTx(mTxFreq)) {
-       LOG(ALERT) << "TX failed to tune";
-       sprintf(response,"RSP TXTUNE 1 %d",freqKhz);
+    mTxFreq = freqKhz * 1.0e3 + mFreqOffset;
+    if (!mRadioInterface->tuneTx(mTxFreq, mChannel)) {
+      LOG(ALERT) << "TX failed to tune";
+      sprintf(response,"RSP TXTUNE 1 %d",freqKhz);
+    } else {
+      sprintf(response,"RSP TXTUNE 0 %d",freqKhz);
    }
-    else
-       sprintf(response,"RSP TXTUNE 0 %d",freqKhz);
  }
  else if (strcmp(command,"SETTSC")==0) {
    // set TSC
    int TSC;
    sscanf(buffer,"%3s %s %d",cmdcheck,command,&TSC);
-    if (mOn)
+    if (mOn || (TSC<0) || (TSC>7))
      sprintf(response,"RSP SETTSC 1 %d",TSC);
    else {
      mTSC = TSC;
@@ -594,7 +479,7 @@ void Transceiver::driveControl()
    }
  }
  else if (strcmp(command,"SETSLOT")==0) {
-    // set TSC 
+    // set slot type
    int  corrCode;
    int  timeslot;
    sscanf(buffer,"%3s %s %d %d",cmdcheck,command,&timeslot,&corrCode);
@@ -603,13 +488,14 @@ void Transceiver::driveControl()
      sprintf(response,"RSP SETSLOT 1 %d %d",timeslot,corrCode);
      return;
    }     
-    mChanType[timeslot] = (ChannelCombination) corrCode;
-    setModulus(timeslot);
+    mDriveLoop->setTimeslot(mChannel, timeslot, (DriveLoop::ChannelCombination) corrCode);
+    mDriveLoop->setModulus(mChannel, timeslot);
    sprintf(response,"RSP SETSLOT 0 %d %d",timeslot,corrCode);

  }
  else {
    LOG(WARNING) << "bogus command " << command << " on control interface.";
+    sprintf(response,"RSP ERR 1");
  }

  mControlSocket.write(response,strlen(response)+1);
@@ -618,14 +504,24 @@ void Transceiver::driveControl()

 bool Transceiver::driveTransmitPriorityQueue() 
 {
-
  char buffer[gSlotLen+50];

-  // check data socket
-  size_t msgLen = mDataSocket.read(buffer);
+  if (!mOn)
+    return true;

-  if (msgLen!=gSlotLen+1+4+1) {
-    LOG(ERR) << "badly formatted packet on GSM->TRX interface";
+  try { 
+    size_t msgLen = mDataSocket.read(buffer);
+    if (msgLen!=gSlotLen+1+4+1) {
+      LOG(ERR) << "badly formatted packet on GSM->TRX interface";
+      return false;
+    }
+  } catch (...) {
+    if (!mOn) {
+      /* Shutdown condition. End the thread. */
+      return true;
+    }
+
+    LOG(ALERT) << "Caught UHD socket exception";
    return false;
  }

@@ -634,28 +530,12 @@ bool Transceiver::driveTransmitPriorityQueue()
  for (int i = 0; i < 4; i++)
    frameNum = (frameNum << 8) | (0x0ff & buffer[i+1]);
  
-  /*
-  if (GSM::Time(frameNum,timeSlot) >  mTransmitDeadlineClock + GSM::Time(51,0)) {
-    // stale burst
-    //LOG(DEBUG) << "FAST! "<< GSM::Time(frameNum,timeSlot);
-    //writeClockInterface();
-    }*/
-
-/*
-  DAB -- Just let these go through the demod.
-  if (GSM::Time(frameNum,timeSlot) < mTransmitDeadlineClock) {
-    // stale burst from GSM core
-    LOG(NOTICE) << "STALE packet on GSM->TRX interface at time "<< GSM::Time(frameNum,timeSlot);
-    return false;
-  }
-*/
-  
  // periodically update GSM core clock
-  LOG(DEBUG) << "mTransmitDeadlineClock " << mTransmitDeadlineClock
-		<< " mLastClockUpdateTime " << mLastClockUpdateTime;
-  if (mTransmitDeadlineClock > mLastClockUpdateTime + GSM::Time(216,0))
-    writeClockInterface();
-
+  LOG(DEBUG) << "mTransmitDeadlineClock " << mDriveLoop->getDeadlineClock()
+             << " mLastClockUpdateTime " << mDriveLoop->getLastClockUpdate();
+  if (mDriveLoop->getDeadlineClock() > mDriveLoop->getLastClockUpdate() + GSM::Time(216,0)) {
+    mDriveLoop->writeClockInterface();
+  }

  LOG(DEBUG) << "rcvd. burst at: " << GSM::Time(frameNum,timeSlot);
  
@@ -676,154 +556,106 @@ bool Transceiver::driveTransmitPriorityQueue()


 }
- 
-void Transceiver::driveReceiveFIFO() 
+
+Thread::ReturnStatus FIFOServiceLoopThread::shutdown()
 {
+  Transceiver *transceiver = (Transceiver *)mThreadData;

-  SoftVector *rxBurst = NULL;
-  int RSSI;
-  int TOA;  // in 1/256 of a symbol
-  GSM::Time burstTime;
+  if (transceiver == NULL)
+    // Nothing to do
+    return ALREADY_IDLE;

-  mRadioInterface->driveReceiveRadio();
-
-  rxBurst = pullRadioVector(burstTime,RSSI,TOA);
-
-  if (rxBurst) { 
-
-    LOG(DEBUG) << "burst parameters: "
-	  << " time: " << burstTime
-	  << " RSSI: " << RSSI
-	  << " TOA: "  << TOA
-	  << " bits: " << *rxBurst;
-    
-    char burstString[gSlotLen+10];
-    burstString[0] = burstTime.TN();
-    for (int i = 0; i < 4; i++)
-      burstString[1+i] = (burstTime.FN() >> ((3-i)*8)) & 0x0ff;
-    burstString[5] = RSSI;
-    burstString[6] = (TOA >> 8) & 0x0ff;
-    burstString[7] = TOA & 0x0ff;
-    SoftVector::iterator burstItr = rxBurst->begin();
-
-    for (unsigned int i = 0; i < gSlotLen; i++) {
-      burstString[8+i] =(char) round((*burstItr++)*255.0);
-    }
-    burstString[gSlotLen+9] = '\0';
-    delete rxBurst;
-
-    mDataSocket.write(burstString,gSlotLen+10);
+  transceiver->mFIFOServiceLoop.requestThreadStop();
+  if (transceiver->mReceiveFIFO != NULL) {
+    // Write twice, because read() function may read twice in case of NULL.
+    transceiver->mReceiveFIFO->write(NULL);
+    transceiver->mReceiveFIFO->write(NULL);
  }
-
+  return transceiver->mFIFOServiceLoop.stopThread();
 }

-void Transceiver::driveTransmitFIFO() 
+void FIFOServiceLoopThread::runThread()
 {
+  Transceiver *transceiver = (Transceiver *)mThreadData;

-  /**
-      Features a carefully controlled latency mechanism, to 
-      assure that transmit packets arrive at the radio/USRP
-      before they need to be transmitted.
+  while (isThreadRunning()) {
+    transceiver->pullFIFO();
+  }

-      Deadline clock indicates the burst that needs to be
-      pushed into the FIFO right NOW.  If transmit queue does
-      not have a burst, stick in filler data.
-  */
+  LOG(DEBUG) << "FIFOServiceLoopThread has finished operations";
+}

-
-  RadioClock *radioClock = (mRadioInterface->getClock());
+Thread::ReturnStatus ControlServiceLoopThread::shutdown()
+{
+  Transceiver *transceiver = (Transceiver *)mThreadData;
  
-  if (mOn) {
-    //radioClock->wait(); // wait until clock updates
-    LOG(DEBUG) << "radio clock " << radioClock->get();
-    while (radioClock->get() + mTransmitLatency > mTransmitDeadlineClock) {
-      // if underrun, then we're not providing bursts to radio/USRP fast
-      //   enough.  Need to increase latency by one GSM frame.
-      if (mRadioInterface->getBus() == RadioDevice::USB) {
-        if (mRadioInterface->isUnderrun()) {
-          // only update latency at the defined frame interval
-          if (radioClock->get() > mLatencyUpdateTime + GSM::Time(USB_LATENCY_INTRVL)) {
-            mTransmitLatency = mTransmitLatency + GSM::Time(1,0);
-            LOG(INFO) << "new latency: " << mTransmitLatency;
-            mLatencyUpdateTime = radioClock->get();
-          }
-        }
-        else {
-          // if underrun hasn't occurred in the last sec (216 frames) drop
-          //    transmit latency by a timeslot
-          if (mTransmitLatency > GSM::Time(USB_LATENCY_MIN)) {
-              if (radioClock->get() > mLatencyUpdateTime + GSM::Time(216,0)) {
-              mTransmitLatency.decTN();
-              LOG(INFO) << "reduced latency: " << mTransmitLatency;
-              mLatencyUpdateTime = radioClock->get();
-            }
-          }
-        }
-      }
-      // time to push burst to transmit FIFO
-      pushRadioVector(mTransmitDeadlineClock);
-      mTransmitDeadlineClock.incTN();
-    }
-    
+  if (transceiver == NULL)
+    // Nothing to do
+    return ALREADY_IDLE;
+
+  transceiver->mControlServiceLoop.requestThreadStop();
+  // FIXME: We should use shutdown() here, but the socket should be
+  //        re-openned on the next start() then. Righ now the socket
+  //        is created in the constructor and if we shutdown() it here,
+  //        we'll get errors when we try to use it on the next start.
+//  transceiver->mControlSocket.shutdown();
+  {
+    // mBasePort+1 is mControlSocket port
+    UDPSocket tmpSock(0, "127.0.0.1", transceiver->mBasePort+1);
+    tmpSock.write(NULL, 0);
  }
-  // FIXME -- This should not be a hard spin.
-  // But any delay here causes us to throw omni_thread_fatal.
-  //else radioClock->wait();
+  return transceiver->mControlServiceLoop.stopThread();
 }

-
-
-void Transceiver::writeClockInterface()
+void ControlServiceLoopThread::runThread()
 {
-  char command[50];
-  // FIXME -- This should be adaptive.
-  sprintf(command,"IND CLOCK %llu",(unsigned long long) (mTransmitDeadlineClock.FN()+2));
+  Transceiver *transceiver = (Transceiver *)mThreadData;

-  LOG(INFO) << "ClockInterface: sending " << command;
-
-  mClockSocket.write(command,strlen(command)+1);
-
-  mLastClockUpdateTime = mTransmitDeadlineClock;
-
-}   
-  
-
-
-
-void *FIFOServiceLoopAdapter(Transceiver *transceiver)
-{
-  transceiver->setPriority();
-
-  while (1) {
-    transceiver->driveReceiveFIFO();
-    transceiver->driveTransmitFIFO();
-    pthread_testcancel();
-  }
-  return NULL;
-}
-
-void *ControlServiceLoopAdapter(Transceiver *transceiver)
-{
-  while (1) {
+  while (isThreadRunning()) {
    transceiver->driveControl();
-    pthread_testcancel();
  }
-  return NULL;
+
+  LOG(DEBUG) << "ControlServiceLoopThread has finished operations";
 }

-void *TransmitPriorityQueueServiceLoopAdapter(Transceiver *transceiver)
+Thread::ReturnStatus TransmitPriorityQueueServiceLoopThread::shutdown()
 {
-  while (1) {
+  Transceiver *transceiver = (Transceiver *)mThreadData;
+  
+  if (transceiver == NULL)
+    // Nothing to do
+    return ALREADY_IDLE;
+
+  transceiver->mTransmitPriorityQueueServiceLoop.requestThreadStop();
+  // FIXME: We should use shutdown() here, but the socket should be
+  //        re-openned on the next start() then. Righ now the socket
+  //        is created in the constructor and if we shutdown() it here,
+  //        we'll get errors when we try to use it on the next start.
+//  transceiver->mDataSocket.shutdown();
+  {
+    // mBasePort+2 is mDataSocket port
+    UDPSocket tmpSock(0, "127.0.0.1", transceiver->mBasePort+2);
+    tmpSock.write(NULL, 0);
+  }
+  return transceiver->mTransmitPriorityQueueServiceLoop.stopThread();
+}
+
+void TransmitPriorityQueueServiceLoopThread::runThread()
+{
+  Transceiver *transceiver = (Transceiver *)mThreadData;
+
+  while (isThreadRunning()) {
    bool stale = false;
+
    // Flush the UDP packets until a successful transfer.
    while (!transceiver->driveTransmitPriorityQueue()) {
      stale = true; 
    }
    if (stale) {
      // If a packet was stale, remind the GSM stack of the clock.
-      transceiver->writeClockInterface();
+      transceiver->getDriveLoop()->writeClockInterface();
    }
-    pthread_testcancel();
  }
-  return NULL;
+
+  LOG(DEBUG) << "TransmitPriorityQueueServiceLoopThread has finished operations";
 }
--- a/Transceiver52M/Transceiver.h
+++ b/Transceiver52M/Transceiver.h
@@ -1,5 +1,6 @@
 /*
-* Copyright 2008 Free Software Foundation, Inc.
+* Copyright 2008, 2012 Free Software Foundation, Inc.
+* Copyright 2013 Alexander Chemeris <Alexander.Chemeris@fairwaves.ru>
 *
 * This software is distributed under the terms of the GNU Public License.
 * See the COPYING file in the main directory for details.
@@ -29,6 +30,7 @@
 	TRANSMIT_LOGGING	write every burst on the given slot to a log
 */

+#include "DriveLoop.h"
 #include "radioInterface.h"
 #include "Interthread.h"
 #include "GSMCommon.h"
@@ -40,63 +42,63 @@
 /** Define this to be the slot number to be logged. */
 //#define TRANSMIT_LOGGING 1

+/** FIFO thread loop */
+class FIFOServiceLoopThread : public Thread {
+public:
+  FIFOServiceLoopThread() : Thread("FIFOServiceLoopThread") {}
+  Thread::ReturnStatus shutdown();
+
+protected:
+  virtual void runThread();
+};
+
+/** control message handler thread loop */
+class ControlServiceLoopThread : public Thread {
+public:
+  ControlServiceLoopThread() : Thread("ControlServiceLoopThread") {}
+  Thread::ReturnStatus shutdown();
+
+protected:
+  virtual void runThread();
+};
+
+/** transmit queueing thread loop */
+class TransmitPriorityQueueServiceLoopThread : public Thread {
+public:
+  TransmitPriorityQueueServiceLoopThread() : Thread("TransmitPriorityQueueServiceLoopThread") {}
+  Thread::ReturnStatus shutdown();
+
+protected:
+  virtual void runThread();
+};
+
 /** The Transceiver class, responsible for physical layer of basestation */
 class Transceiver {
  
 private:
+  DriveLoop *mDriveLoop;

-  GSM::Time mTransmitLatency;     ///< latency between basestation clock and transmit deadline clock
-  GSM::Time mLatencyUpdateTime;   ///< last time latency was updated
-
+  int mBasePort;                  ///< Base port address for all our ports
+  std::string mTRXAddress;        ///< Address of the BTS TRX control interface
  UDPSocket mDataSocket;	  ///< socket for writing to/reading from GSM core
  UDPSocket mControlSocket;	  ///< socket for writing/reading control commands from GSM core
-  UDPSocket mClockSocket;	  ///< socket for writing clock updates to GSM core

-  VectorQueue  mTransmitPriorityQueue;   ///< priority queue of transmit bursts received from GSM core
-  VectorFIFO*  mTransmitFIFO;     ///< radioInterface FIFO of transmit bursts 
+  VectorQueue  *mTransmitPriorityQueue;   ///< priority queue of transmit bursts received from GSM core
  VectorFIFO*  mReceiveFIFO;      ///< radioInterface FIFO of receive bursts 

-  Thread *mFIFOServiceLoopThread;  ///< thread to push/pull bursts into transmit/receive FIFO
-  Thread *mControlServiceLoopThread;       ///< thread to process control messages from GSM core
-  Thread *mTransmitPriorityQueueServiceLoopThread;///< thread to process transmit bursts from GSM core
+  friend class FIFOServiceLoopThread;
+  FIFOServiceLoopThread mFIFOServiceLoop;      ///< thread to push/pull bursts into transmit/receive FIFO
+  friend class ControlServiceLoopThread;
+  ControlServiceLoopThread mControlServiceLoop;   ///< thread to process control messages from GSM core
+  friend class TransmitPriorityQueueServiceLoopThread;
+  TransmitPriorityQueueServiceLoopThread mTransmitPriorityQueueServiceLoop;///< thread to process transmit bursts from GSM core

-  GSM::Time mTransmitDeadlineClock;       ///< deadline for pushing bursts into transmit FIFO 
-  GSM::Time mLastClockUpdateTime;         ///< last time clock update was sent up to core
+  int mChannel;                           ///< channelizer attach number between 0 and 'M-1'

  RadioInterface *mRadioInterface;	  ///< associated radioInterface object
  double txFullScale;                     ///< full scale input to radio
  double rxFullScale;                     ///< full scale output to radio

-  /** Codes for burst types of received bursts*/
-  typedef enum {
-    OFF,               ///< timeslot is off
-    TSC,	       ///< timeslot should contain a normal burst
-    RACH,	       ///< timeslot should contain an access burst
-    IDLE	       ///< timeslot is an idle (or dummy) burst
-  } CorrType;
-
-
-  /** Codes for channel combinations */
-  typedef enum {
-    FILL,               ///< Channel is transmitted, but unused
-    I,                  ///< TCH/FS
-    II,                 ///< TCH/HS, idle every other slot
-    III,                ///< TCH/HS
-    IV,                 ///< FCCH+SCH+CCCH+BCCH, uplink RACH
-    V,                  ///< FCCH+SCH+CCCH+BCCH+SDCCH/4+SACCH/4, uplink RACH+SDCCH/4
-    VI,                 ///< CCCH+BCCH, uplink RACH
-    VII,                ///< SDCCH/8 + SACCH/8
-    VIII,               ///< TCH/F + FACCH/F + SACCH/M
-    IX,                 ///< TCH/F + SACCH/M
-    X,                  ///< TCH/FD + SACCH/MD
-    XI,                 ///< PBCCH+PCCCH+PDTCH+PACCH+PTCCH
-    XII,                ///< PCCCH+PDTCH+PACCH+PTCCH
-    XIII,               ///< PDTCH+PACCH+PTCCH
-    NONE,               ///< Channel is inactive, default
-    LOOPBACK            ///< similar go VII, used in loopback testing
-  } ChannelCombination;
-
-
  /** unmodulate a modulated burst */
 #ifdef TRANSMIT_LOGGING
  void unModulateVector(signalVector wVector); 
@@ -115,29 +117,24 @@ private:
 			   int &RSSI,
 			   int &timingOffset);
   
-  /** Set modulus for specific timeslot */
-  void setModulus(int timeslot);
-
-  /** return the expected burst type for the specified timestamp */
-  CorrType expectedCorrType(GSM::Time currTime);
-
  /** send messages over the clock socket */
  void writeClockInterface(void);

+  void pullFIFO(void);                 ///< blocking call on receive FIFO 
+
  signalVector *gsmPulse;              ///< the GSM shaping pulse for modulation

  int mSamplesPerSymbol;               ///< number of samples per GSM symbol

  bool mOn;			       ///< flag to indicate that transceiver is powered on
-  ChannelCombination mChanType[8];     ///< channel types for all timeslots
+  bool mRunning;                       ///< flag to indicate control loop is running
+  bool mPrimary;                       ///< flag to indicate C0 channel 
  double mTxFreq;                      ///< the transmit frequency
  double mRxFreq;                      ///< the receive frequency
+  double mFreqOffset;                  ///< RF frequency offset
  int mPower;                          ///< the transmit power in dB
-  unsigned mTSC;                       ///< the midamble sequence code
  double mEnergyThreshold;             ///< threshold to determine if received data is potentially a GSM burst
  GSM::Time prevFalseDetectionTime;    ///< last timestamp of a false energy detection
-  int fillerModulus[8];                ///< modulus values of all timeslots, in frames
-  signalVector *fillerTable[102][8];   ///< table of modulated filler waveforms for all timeslots
  unsigned mMaxExpectedDelay;            ///< maximum expected time-of-arrival offset in GSM symbols

  GSM::Time    channelEstimateTime[8]; ///< last timestamp of each timeslot's channel estimate
@@ -148,6 +145,8 @@ private:
  float        chanRespOffset[8];      ///< most recent timing offset, e.g. TOA, of all timeslots
  complex      chanRespAmplitude[8];   ///< most recent channel amplitude of all timeslots

+  static int mTSC;                     ///< the midamble sequence code
+
 public:

  /** Transceiver constructor 
@@ -157,23 +156,19 @@ public:
      @param wTransmitLatency initial setting of transmit latency
      @param radioInterface associated radioInterface object
  */
-  Transceiver(int wBasePort,
-	      const char *TRXAddress,
-	      int wSamplesPerSymbol,
-	      GSM::Time wTransmitLatency,
-	      RadioInterface *wRadioInterface);
-   
+  Transceiver(int wBasePort, const char *TRXAddress,
+	      DriveLoop *wDriveLoop, RadioInterface *wRadioInterface,
+	      int wSamplesPerSymbol = SAMPSPERSYM,
+	      int wChannel = 0, bool wPrimary = true);
+
  /** Destructor */
  ~Transceiver();

  /** start the Transceiver */
  void start();

-  /** attach the radioInterface receive FIFO */
-  void receiveFIFO(VectorFIFO *wFIFO) { mReceiveFIFO = wFIFO;}
-
-  /** attach the radioInterface transmit FIFO */
-  void transmitFIFO(VectorFIFO *wFIFO) { mTransmitFIFO = wFIFO;}
+  /** shutdown (teardown threads) the Transceiver */
+  void shutdown();

 protected:

@@ -192,25 +187,17 @@ protected:
  */
  bool driveTransmitPriorityQueue();

-  friend void *FIFOServiceLoopAdapter(Transceiver *);
-
-  friend void *ControlServiceLoopAdapter(Transceiver *);
-
-  friend void *TransmitPriorityQueueServiceLoopAdapter(Transceiver *);
-
  void reset();

+  /** return transceiver on/off status */ 
+  bool on() { return mOn; }
+
+  /** return control loop operational status */ 
+  bool running() { return mRunning; }
+
+  /** return the drive loop pointer */
+  DriveLoop *getDriveLoop() { return mDriveLoop; }
+  
  /** set priority on current thread */
  void setPriority() { mRadioInterface->setPriority(); }
-
 };
-
-/** FIFO thread loop */
-void *FIFOServiceLoopAdapter(Transceiver *);
-
-/** control message handler thread loop */
-void *ControlServiceLoopAdapter(Transceiver *);
-
-/** transmit queueing thread loop */
-void *TransmitPriorityQueueServiceLoopAdapter(Transceiver *);
-
--- a/Transceiver52M/UHDDevice.cpp
+++ b/Transceiver52M/UHDDevice.cpp
@@ -3,6 +3,7 @@
 * Written by Thomas Tsou <ttsou@vt.edu>
 *
 * Copyright 2010,2011 Free Software Foundation, Inc.
+ * Copyright 2013 Alexander Chemeris <Alexander.Chemeris@fairwaves.ru>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
@@ -32,31 +33,98 @@
 #include "config.h"
 #endif

-#define U1_DEFAULT_CLK_RT 64e6
-#define U2_DEFAULT_CLK_RT 100e6 
+#define NUM_TX_CHANS      2
+#define NUM_RX_CHANS      NUM_TX_CHANS
+#define TX_CHAN_OFFSET    2e6
+#define B100_CLK_RT       52e6 
+#define USRP2_BASE_RT     400e3
+#define TX_AMPL           0.3;
+#define SAMPLE_BUF_SZ     (1 << 20)
+
+enum uhd_dev_type {
+	USRP1,
+	USRP2,
+	B100,
+	UMTRX,
+	NUM_USRP_TYPES,
+};
+
+struct uhd_dev_offset {
+	enum uhd_dev_type type;
+	int sps;
+	double offset;
+};
+
+static TIMESTAMP init_rd_ts = 0;

 /*
-    master_clk_rt     - Master clock frequency - ignored if host resampling is
-                        enabled
+ * Tx / Rx sample offset values. In a perfect world, there is no group delay
+ * though analog components, and behaviour through digital filters exactly
+ * matches calculated values. In reality, there are unaccounted factors,
+ * which are captured in these empirically measured (using a loopback test)
+ * timing correction values.
+ *
+ * Notes:
+ *   USRP1 with timestamps is not supported by UHD.
+ */
+static struct uhd_dev_offset uhd_offsets[NUM_USRP_TYPES * 3] = {
+	{ USRP1, 1, 0.0 },
+	{ USRP1, 2, 0.0 },
+	{ USRP1, 4, 0.0 },
+	{ USRP2, 1, 5.4394e-5 },
+	{ USRP2, 2, 0.0 },
+	{ USRP2, 4, 0.0 },
+	{ B100,  1, 9.4778e-5 },
+	{ B100,  2, 5.1100e-5 },
+	{ B100,  4, 2.9418e-5 },
+	{ UMTRX, 1, 9.1738e-5 },
+	{ UMTRX, 2, 0.0 },
+	{ UMTRX, 4, 0.0 },
+};

-    rx_smpl_offset    - Timing correction in seconds between receive and
-                        transmit timestamps. This value corrects for delays on
-                        on the RF side of the timestamping point of the device.
-                        This value is generally empirically measured.
+static double get_dev_offset(enum uhd_dev_type type, int sps)
+{
+	if (type == USRP1) {
+		LOG(ERR) << "Invalid device type";
+		return 0.0;
+	}

-    smpl_buf_sz       - The receive sample buffer size in bytes.
+	switch (sps) {
+	case 1:
+		return uhd_offsets[3 * type + 0].offset;
+	case 2:
+		return uhd_offsets[3 * type + 1].offset;
+	case 4:
+		return uhd_offsets[3 * type + 2].offset;
+	}

-    tx_ampl           - Transmit amplitude must be between 0 and 1.0
-*/
-const double master_clk_rt = 52e6;
-const size_t smpl_buf_sz = (1 << 20);
-const float tx_ampl = .3;
+	LOG(ERR) << "Unsupported samples-per-symbols: " << sps;
+	return 0.0;	
+}

-#ifdef RESAMPLE
-const double rx_smpl_offset = .00005;
-#else
-const double rx_smpl_offset = .0000869;
-#endif
+/*
+ * Select sample rate based on device type and requested samples-per-symbol.
+ * The base rate is either GSM symbol rate, 270.833 kHz, or the minimum
+ * usable channel spacing of 400 kHz.
+ */ 
+static double select_rate(uhd_dev_type type, int sps)
+{
+	if ((sps != 4) && (sps != 2) && (sps != 1))
+		return -9999.99;
+
+	switch (type) {
+	case USRP2:
+		return USRP2_BASE_RT * sps;
+		break;
+	case B100:
+	case UMTRX:
+		return GSMRATE * sps;
+		break;
+	}
+
+	LOG(ALERT) << "Unknown device type " << type;
+	return -9999.99;
+}

 /** Timestamp conversion
    @param timestamp a UHD or OpenBTS timestamp
@@ -139,6 +207,15 @@ private:
 	size_t data_end;
 };

+/** transmit queueing thread loop */
+class UHDAsyncEventThread : public Thread {
+public:
+	UHDAsyncEventThread() : Thread("UHDAsyncEventThread") {}
+
+protected:
+	virtual void runThread();
+};
+
 /*
    uhd_device - UHD implementation of the Device interface. Timestamped samples
                are sent to and received from the device. An intermediate buffer
@@ -148,44 +225,48 @@ private:
 */
 class uhd_device : public RadioDevice {
 public:
-	uhd_device(double rate, bool skip_rx);
+	uhd_device(int sps, bool skip_rx);
 	~uhd_device();

-	bool open(const std::string &args);
+	int open(const std::string &args);
 	bool start();
 	bool stop();
 	void restart(uhd::time_spec_t ts);
 	void setPriority();
-	enum busType getBus() { return bus; }
+	enum TxWindowType getWindowType() { return tx_window; }

-	int readSamples(short *buf, int len, bool *overrun, 
-			TIMESTAMP timestamp, bool *underrun, unsigned *RSSI);
+	int readSamples(short **buf, int chans, int len, TIMESTAMP timestamp,
+			bool *overrun, bool *underrun, unsigned *RSSI);

-	int writeSamples(short *buf, int len, bool *underrun, 
-			 TIMESTAMP timestamp, bool isControl);
+	int writeSamples(short **buf, int chans, int len, TIMESTAMP timestamp,
+			 bool *underrun, bool isControl);

 	bool updateAlignment(TIMESTAMP timestamp);

-	bool setTxFreq(double wFreq);
-	bool setRxFreq(double wFreq);
+	bool setTxFreq(double wFreq, int chan);
+	bool setRxFreq(double wFreq, int chan);

-	inline TIMESTAMP initialWriteTimestamp() { return 0; }
-	inline TIMESTAMP initialReadTimestamp() { return 0; }
+	inline TIMESTAMP initialWriteTimestamp() { return init_rd_ts; }
+	inline TIMESTAMP initialReadTimestamp() { return init_rd_ts; }

-	inline double fullScaleInputValue() { return 32000 * tx_ampl; }
+	inline double fullScaleInputValue() { return 32000 * TX_AMPL; }
 	inline double fullScaleOutputValue() { return 32000; }

-	double setRxGain(double db);
-	double getRxGain(void) { return rx_gain; }
+	double setRxGain(double db, int chan);
+	double getRxGain(int chan) { return !chan ? rx_gain[0] : tx_gain[1]; }
 	double maxRxGain(void) { return rx_gain_max; }
 	double minRxGain(void) { return rx_gain_min; }

-	double setTxGain(double db);
+	double setTxGain(double db, int chan);
 	double maxTxGain(void) { return tx_gain_max; }
 	double minTxGain(void) { return tx_gain_min; }
+	void setTxAntenna(std::string &name);
+	void setRxAntenna(std::string &name);
+	std::string getRxAntenna();
+	std::string getTxAntenna();

-	double getTxFreq() { return tx_freq; }
-	double getRxFreq() { return rx_freq; }
+	double getTxFreq(int chan) { return !chan ? tx_freq[0] : tx_freq[1]; }
+	double getRxFreq(int chan) { return !chan ? rx_freq[0] : rx_freq[1]; }

 	inline double getSampleRate() { return actual_smpl_rt; }
 	inline double numberRead() { return rx_pkt_cnt; }
@@ -195,6 +276,7 @@ public:
 	    @return true if message received or false on timeout or error
 	*/
 	bool recv_async_msg();
+	bool running() { return started; }

 	enum err_code {
 		ERROR_TIMING = -1,
@@ -204,14 +286,18 @@ public:

 private:
 	uhd::usrp::multi_usrp::sptr usrp_dev;
-	enum busType bus;
+	uhd::tx_streamer::sptr tx_stream;
+	uhd::rx_streamer::sptr rx_stream;
+	enum TxWindowType tx_window;
+	enum uhd_dev_type dev_type;

+	int sps;
 	double desired_smpl_rt, actual_smpl_rt;

-	double tx_gain, tx_gain_min, tx_gain_max;
-	double rx_gain, rx_gain_min, rx_gain_max;
+	double tx_gain[NUM_TX_CHANS], tx_gain_min, tx_gain_max;
+	double rx_gain[NUM_RX_CHANS], rx_gain_min, rx_gain_max;

-	double tx_freq, rx_freq;
+	double tx_freq[NUM_TX_CHANS], rx_freq[NUM_RX_CHANS];
 	size_t tx_spp, rx_spp;

 	bool started;
@@ -223,11 +309,12 @@ private:
 	uhd::time_spec_t prev_ts;

 	TIMESTAMP ts_offset;
-	smpl_buf *rx_smpl_buf;
+	smpl_buf *rx_smpl_buf[NUM_RX_CHANS];

 	void init_gains();
 	void set_ref_clk(bool ext_clk);
-	double set_rates(double rate);
+	int set_master_clk(double rate);
+	int set_rates(double rate);
 	bool parse_dev_type();
 	bool flush_recv(size_t num_pkts);
 	int check_rx_md_err(uhd::rx_metadata_t &md, ssize_t num_smpls);
@@ -235,14 +322,14 @@ private:
 	std::string str_code(uhd::rx_metadata_t metadata);
 	std::string str_code(uhd::async_metadata_t metadata);

-	Thread async_event_thrd;
+	UHDAsyncEventThread async_event_thrd;
 };

-void *async_event_loop(uhd_device *dev)
+void UHDAsyncEventThread::runThread()
 {
-	while (1) {
+	uhd_device *dev = (uhd_device *)mThreadData;
+	while (isThreadRunning()) {
 		dev->recv_async_msg();
-		pthread_testcancel();
 	}
 }

@@ -268,23 +355,34 @@ void uhd_msg_handler(uhd::msg::type_t type, const std::string &msg)
 	}
 }

-uhd_device::uhd_device(double rate, bool skip_rx)
-	: desired_smpl_rt(rate), actual_smpl_rt(0),
-	  tx_gain(0.0), tx_gain_min(0.0), tx_gain_max(0.0),
-	  rx_gain(0.0), rx_gain_min(0.0), rx_gain_max(0.0),
-	  tx_freq(0.0), rx_freq(0.0), tx_spp(0), rx_spp(0),
-	  started(false), aligned(false), rx_pkt_cnt(0), drop_cnt(0),
-	  prev_ts(0,0), ts_offset(0), rx_smpl_buf(NULL)
+uhd_device::uhd_device(int sps, bool skip_rx)
+	: tx_gain_min(0.0), tx_gain_max(0.0),
+	  rx_gain_min(0.0), rx_gain_max(0.0),
+	  tx_spp(0), rx_spp(0), started(false), aligned(false),
+	  rx_pkt_cnt(0), drop_cnt(0), prev_ts(0,0), ts_offset(0)
 {
+	this->sps = sps;
 	this->skip_rx = skip_rx;
+
+	for (int i = 0; i < NUM_TX_CHANS; i++) {
+		tx_freq[i] = 0.0f;
+		tx_gain[i] = 0.0f;
+	}
+
+	for (int i = 0; i < NUM_RX_CHANS; i++) {
+		rx_smpl_buf[i] = NULL;
+		rx_freq[i] = 0.0f;
+		rx_gain[i] = 0.0f;
+	}
 }

 uhd_device::~uhd_device()
 {
 	stop();

-	if (rx_smpl_buf)
-		delete rx_smpl_buf;
+	for (int i = 0; i < NUM_RX_CHANS; i++) {
+		delete rx_smpl_buf[i];
+	}
 }

 void uhd_device::init_gains()
@@ -299,95 +397,135 @@ void uhd_device::init_gains()
 	rx_gain_min = range.start();
 	rx_gain_max = range.stop();

-	usrp_dev->set_tx_gain((tx_gain_min + tx_gain_max) / 2);
-	usrp_dev->set_rx_gain((rx_gain_min + rx_gain_max) / 2);
+	for (int i = 0; i < NUM_TX_CHANS; i++) {
+		usrp_dev->set_tx_gain((tx_gain_min + tx_gain_max) / 2, i);
+		tx_gain[i] = usrp_dev->get_tx_gain(i);
+	}

-	tx_gain = usrp_dev->get_tx_gain();
-	rx_gain = usrp_dev->get_rx_gain();
+	for (int i = 0; i < NUM_RX_CHANS; i++) {
+		usrp_dev->set_rx_gain((rx_gain_min + rx_gain_max) / 2, i);
+		rx_gain[i] = usrp_dev->get_rx_gain(i);
+	}

 	return;
 }

 void uhd_device::set_ref_clk(bool ext_clk)
 {
-	uhd::clock_config_t clk_cfg;
-
-	clk_cfg.pps_source = uhd::clock_config_t::PPS_SMA;
-
 	if (ext_clk)
-		clk_cfg.ref_source = uhd::clock_config_t::REF_SMA;
-	else
-		clk_cfg.ref_source = uhd::clock_config_t::REF_INT;
-
-	usrp_dev->set_clock_config(clk_cfg);
+		usrp_dev->set_clock_source("external");

 	return;
 }

-double uhd_device::set_rates(double rate)
+int uhd_device::set_master_clk(double clk_rate)
 {
-	double actual_rt, actual_clk_rt;
+	double actual_clk_rt;

-#ifndef RESAMPLE
-	// Make sure we can set the master clock rate on this device
-	actual_clk_rt = usrp_dev->get_master_clock_rate();
-	if (actual_clk_rt > U1_DEFAULT_CLK_RT) {
-		LOG(ALERT) << "Cannot set clock rate on this device";
-		LOG(ALERT) << "Please compile with host resampling support";
-		return -1.0;
+	try {
+		usrp_dev->set_master_clock_rate(clk_rate);
+		actual_clk_rt = usrp_dev->get_master_clock_rate();
+	} catch (const std::exception &ex) {
+		LOG(ALERT) << "UHD clock rate setting failed: " << clk_rate;
+		LOG(ALERT) << ex.what();
+		return -1;
 	}

-	// Set master clock rate
-	usrp_dev->set_master_clock_rate(master_clk_rt);
-	actual_clk_rt = usrp_dev->get_master_clock_rate();
-
-	if (actual_clk_rt != master_clk_rt) {
+	if (actual_clk_rt != clk_rate) {
 		LOG(ALERT) << "Failed to set master clock rate";
+		LOG(ALERT) << "Requested clock rate " << clk_rate;
 		LOG(ALERT) << "Actual clock rate " << actual_clk_rt;
-		return -1.0;
+		return -1;
+	}
+
+	return 0;
+}
+
+int uhd_device::set_rates(double rate)
+{
+	double offset_limit = 10.0;
+	double tx_offset, rx_offset;
+
+	// B100 is the only device where we set FPGA clocking
+	if (dev_type == B100) {
+		if (set_master_clk(B100_CLK_RT) < 0)
+			return -1;
 	}
-#endif

 	// Set sample rates
-	usrp_dev->set_tx_rate(rate);
-	usrp_dev->set_rx_rate(rate);
-	actual_rt = usrp_dev->get_tx_rate();
+	try {
+		usrp_dev->set_tx_rate(rate);
+		usrp_dev->set_rx_rate(rate);
+	} catch (const std::exception &ex) {
+		LOG(ALERT) << "UHD rate setting failed: " << rate;
+		LOG(ALERT) << ex.what();
+		return -1;
+	}
+	actual_smpl_rt = usrp_dev->get_tx_rate();

-	if (actual_rt != rate) {
+	tx_offset = actual_smpl_rt - rate;
+	rx_offset = usrp_dev->get_rx_rate() - rate;
+	if ((tx_offset > offset_limit) || (rx_offset > offset_limit)) {
 		LOG(ALERT) << "Actual sample rate differs from desired rate";
-		return -1.0;
-	}
-	if (usrp_dev->get_rx_rate() != actual_rt) {
-		LOG(ALERT) << "Transmit and receive sample rates do not match";
-		return -1.0;
+		LOG(ALERT) << "Tx/Rx (" << actual_smpl_rt << "/"
+			   << usrp_dev->get_rx_rate() << ")";
+		return -1;
 	}

-	return actual_rt;
+	return 0;
 }

-double uhd_device::setTxGain(double db)
+double uhd_device::setTxGain(double db, int chan)
 {
-	usrp_dev->set_tx_gain(db);
-	tx_gain = usrp_dev->get_tx_gain();
+	if (chan >= NUM_TX_CHANS) {
+		LOG(ALERT) << "Attempting to set gain on non-existent channel";
+		return 0.0f;
+	}

-	LOG(INFO) << "Set TX gain to " << tx_gain << "dB";
+	usrp_dev->set_tx_gain(db, chan);
+	tx_gain[chan] = usrp_dev->get_tx_gain(chan);
+	LOG(INFO) << "Set TX gain to " << tx_gain[chan] << "dB";

-	return tx_gain;
+	return tx_gain[chan];
 }

-double uhd_device::setRxGain(double db)
+double uhd_device::setRxGain(double db, int chan)
 {
-	usrp_dev->set_rx_gain(db);
-	rx_gain = usrp_dev->get_rx_gain();
+	if (chan >= NUM_RX_CHANS) {
+		LOG(ALERT) << "Attempting to read gain non-existent channel";
+		return 0.0f;
+	}

-	LOG(INFO) << "Set RX gain to " << rx_gain << "dB";
+	usrp_dev->set_rx_gain(db, chan);
+	rx_gain[chan] = usrp_dev->get_rx_gain(chan);
+	LOG(INFO) << "Set RX gain to " << rx_gain[chan] << "dB";

-	return rx_gain;
+	return rx_gain[chan];
+}
+
+void uhd_device::setTxAntenna(std::string &name)
+{
+	usrp_dev->set_tx_antenna(name);
+}
+
+void uhd_device::setRxAntenna(std::string &name)
+{
+	usrp_dev->set_rx_antenna(name);
+}
+
+std::string uhd_device::getTxAntenna()
+{
+	return usrp_dev->get_tx_antenna();
+}
+
+std::string uhd_device::getRxAntenna()
+{
+	return usrp_dev->get_rx_antenna();
 }

 /*
    Parse the UHD device tree and mboard name to find out what device we're
-    dealing with. We need the bus type so that the transceiver knows how to
+    dealing with. We need the window type so that the transceiver knows how to
    deal with the transport latency. Reject the USRP1 because UHD doesn't
    support timestamped samples with it.
 */
@@ -395,34 +533,46 @@ bool uhd_device::parse_dev_type()
 {
 	std::string mboard_str, dev_str;
 	uhd::property_tree::sptr prop_tree;
-	size_t usrp1_str, usrp2_str, b100_str1, b100_str2;
+	size_t usrp1_str, usrp2_str, b100_str, umtrx_str;

 	prop_tree = usrp_dev->get_device()->get_tree();
 	dev_str = prop_tree->access<std::string>("/name").get();
 	mboard_str = usrp_dev->get_mboard_name();

 	usrp1_str = dev_str.find("USRP1");
-	b100_str1 = dev_str.find("B-Series");
-	b100_str2 = mboard_str.find("B100");
+	usrp2_str = dev_str.find("USRP2");
+	umtrx_str = dev_str.find("UmTRX");
+	b100_str = mboard_str.find("B100");

 	if (usrp1_str != std::string::npos) {
 		LOG(ALERT) << "USRP1 is not supported using the UHD driver";
 		LOG(ALERT) << "Please compile with GNU Radio libusrp support";
+		dev_type = USRP1;
 		return false;
 	}

-	if ((b100_str1 != std::string::npos) || (b100_str2 != std::string::npos)) {
-		bus = USB;
-		LOG(INFO) << "Using USB bus for " << dev_str;
+	if (b100_str != std::string::npos) {
+		tx_window = TX_WINDOW_USRP1;
+		LOG(INFO) << "Using USRP1 type transmit window for "
+			  << dev_str << " " << mboard_str;
+		dev_type = B100;
+		return true;
+	} else if (usrp2_str != std::string::npos) {
+		dev_type = USRP2;
+	} else if (umtrx_str != std::string::npos) {
+		dev_type = UMTRX;
 	} else {
-		bus = NET;
-		LOG(INFO) << "Using network bus for " << dev_str;
+		LOG(ALERT) << "Unknown UHD device type";
+		return false;
 	}

+	tx_window = TX_WINDOW_FIXED;
+	LOG(INFO) << "Using fixed transmit window for "
+		  << dev_str << " " << mboard_str;
 	return true;
 }

-bool uhd_device::open(const std::string &args)
+int uhd_device::open(const std::string &args)
 {
 	// Register msg handler
 	uhd::msg::register_handler(&uhd_msg_handler);
@@ -432,7 +582,7 @@ bool uhd_device::open(const std::string &args)
 	uhd::device_addrs_t dev_addrs = uhd::device::find(addr);
 	if (dev_addrs.size() == 0) {
 		LOG(ALERT) << "No UHD devices found with address '" << args << "'";
-		return false;
+		return -1;
 	}

 	// Use the first found device
@@ -441,32 +591,51 @@ bool uhd_device::open(const std::string &args)
 		usrp_dev = uhd::usrp::multi_usrp::make(dev_addrs[0]);
 	} catch(...) {
 		LOG(ALERT) << "UHD make failed, device " << dev_addrs[0].to_string();
-		return false;
+		return -1;
 	}

 	// Check for a valid device type and set bus type
 	if (!parse_dev_type())
-		return false;
+		return -1;

 #ifdef EXTREF
 	set_ref_clk(true);
 #endif
-
-	// Number of samples per over-the-wire packet
-	tx_spp = usrp_dev->get_device()->get_max_send_samps_per_packet();
-	rx_spp = usrp_dev->get_device()->get_max_recv_samps_per_packet();
+	if (NUM_TX_CHANS == 2) {
+		uhd::usrp::subdev_spec_t subdev_spec("A:0 B:0");
+		usrp_dev->set_tx_subdev_spec(subdev_spec);
+		usrp_dev->set_rx_subdev_spec(subdev_spec);
+	}

 	// Set rates
-	actual_smpl_rt = set_rates(desired_smpl_rt);
-	if (actual_smpl_rt < 0)
-		return false;
+	desired_smpl_rt = select_rate(dev_type, sps);
+	if (set_rates(desired_smpl_rt) < 0)
+		return -1;
+
+	// Create TX and RX streamers
+	uhd::stream_args_t stream_args("sc16");
+	for (int i = 0; i < NUM_TX_CHANS; i++)
+		stream_args.channels.push_back(i);
+	tx_stream = usrp_dev->get_tx_stream(stream_args);
+	rx_stream = usrp_dev->get_rx_stream(stream_args);
+
+	// Number of samples per over-the-wire packet
+	tx_spp = tx_stream->get_max_num_samps();
+	rx_spp = rx_stream->get_max_num_samps();

 	// Create receive buffer
-	size_t buf_len = smpl_buf_sz / sizeof(uint32_t);
-	rx_smpl_buf = new smpl_buf(buf_len, actual_smpl_rt);
+	size_t buf_len = SAMPLE_BUF_SZ / sizeof(uint32_t);
+	for (int i = 0; i < NUM_RX_CHANS; i++)
+		rx_smpl_buf[i] = new smpl_buf(buf_len, actual_smpl_rt);

 	// Set receive chain sample offset 
-	ts_offset = (TIMESTAMP)(rx_smpl_offset * actual_smpl_rt);
+	double offset = get_dev_offset(dev_type, sps);
+	if (offset == 0.0) {
+		LOG(ERR) << "Unsupported configuration, no correction applied";
+		ts_offset = 0;
+	} else  {
+		ts_offset = (TIMESTAMP) (offset * actual_smpl_rt);
+	}

 	// Initialize and shadow gain values 
 	init_gains();
@@ -474,28 +643,30 @@ bool uhd_device::open(const std::string &args)
 	// Print configuration
 	LOG(INFO) << "\n" << usrp_dev->get_pp_string();

-	return true;
+	if (dev_type == USRP2)
+		return RESAMP;
+
+	return NORMAL;
 }

 bool uhd_device::flush_recv(size_t num_pkts)
 {
 	uhd::rx_metadata_t md;
 	size_t num_smpls;
-	uint32_t buff[rx_spp];
 	float timeout;

 	// Use .01 sec instead of the default .1 sec
 	timeout = .01;

-	for (size_t i = 0; i < num_pkts; i++) {
-		num_smpls = usrp_dev->get_device()->recv(
-					buff,
-					rx_spp,
-					md,
-					uhd::io_type_t::COMPLEX_INT16,
-					uhd::device::RECV_MODE_ONE_PACKET,
-					timeout);
+	std::vector<std::vector<std::complex<short> > > bufs(
+		NUM_RX_CHANS, std::vector<std::complex<short> >(rx_spp));
+	std::vector<std::complex<short> *> buf_ptrs;
+	for (int i = 0; i < bufs.size(); i++)
+		buf_ptrs.push_back(&bufs[i].front());

+	for (size_t i = 0; i < num_pkts; i++) {
+		num_smpls = rx_stream->recv(buf_ptrs, rx_spp, md,
+					    timeout, true);
 		if (!num_smpls) {
 			switch (md.error_code) {
 			case uhd::rx_metadata_t::ERROR_CODE_TIMEOUT:
@@ -511,17 +682,15 @@ bool uhd_device::flush_recv(size_t num_pkts)

 void uhd_device::restart(uhd::time_spec_t ts)
 {
-	uhd::stream_cmd_t cmd = uhd::stream_cmd_t::STREAM_MODE_STOP_CONTINUOUS;
-	usrp_dev->issue_stream_cmd(cmd);
-
-	flush_recv(50);
-
 	usrp_dev->set_time_now(ts);
 	aligned = false;

-	cmd = uhd::stream_cmd_t::STREAM_MODE_START_CONTINUOUS;
-	cmd.stream_now = true;
+	uhd::stream_cmd_t cmd = uhd::stream_cmd_t::STREAM_MODE_START_CONTINUOUS;
+	cmd.time_spec = uhd::time_spec_t(0.1);
+	cmd.stream_now = false;
 	usrp_dev->issue_stream_cmd(cmd);
+
+	uhd::rx_metadata_t md;
 }

 bool uhd_device::start()
@@ -533,10 +702,11 @@ bool uhd_device::start()
 		return false;
 	}

+	started = true;
 	setPriority();

 	// Start asynchronous event (underrun check) loop
-	async_event_thrd.start((void * (*)(void*))async_event_loop, (void*)this);
+	async_event_thrd.startThread((void*)this);

 	// Start streaming
 	restart(uhd::time_spec_t(0.0));
@@ -545,18 +715,22 @@ bool uhd_device::start()
 	double time_now = usrp_dev->get_time_now().get_real_secs();
 	LOG(INFO) << "The current time is " << time_now << " seconds";

-	started = true;
 	return true;
 }

 bool uhd_device::stop()
 {
+	if (!started)
+		return false;
+
+	async_event_thrd.stopThread();
+	started = false;
+
 	uhd::stream_cmd_t stream_cmd = 
 		uhd::stream_cmd_t::STREAM_MODE_STOP_CONTINUOUS;

 	usrp_dev->issue_stream_cmd(stream_cmd);

-	started = false;
 	return true;
 }

@@ -607,40 +781,48 @@ int uhd_device::check_rx_md_err(uhd::rx_metadata_t &md, ssize_t num_smpls)
 	return 0;
 }

-int uhd_device::readSamples(short *buf, int len, bool *overrun,
-			TIMESTAMP timestamp, bool *underrun, unsigned *RSSI)
+int uhd_device::readSamples(short **buf, int chans, int len,
+			    TIMESTAMP timestamp, bool *overrun,
+			    bool *underrun, unsigned *RSSI)
 {
 	ssize_t rc;
 	uhd::time_spec_t ts;
 	uhd::rx_metadata_t metadata;
-	uint32_t pkt_buf[rx_spp];

-	if (skip_rx)
+	if (skip_rx) {
+		LOG(INFO) << "Skipping Rx";
 		return 0;
+	}
+
+	if (chans != NUM_RX_CHANS) {
+		LOG(ERR) << "Number of requested channels does not match build";
+		return -1;
+	}

 	// Shift read time with respect to transmit clock
 	timestamp += ts_offset;

 	ts = convert_time(timestamp, actual_smpl_rt);
-	LOG(DEBUG) << "Requested timestamp = " << ts.get_real_secs();
+	LOG(DEBUG) << "Requested UHD timestamp = " << ts.get_real_secs();

 	// Check that timestamp is valid
-	rc = rx_smpl_buf->avail_smpls(timestamp);
+	rc = rx_smpl_buf[0]->avail_smpls(timestamp);
 	if (rc < 0) {
-		LOG(ERR) << rx_smpl_buf->str_code(rc);
-		LOG(ERR) << rx_smpl_buf->str_status();
+		LOG(ERR) << rx_smpl_buf[0]->str_code(rc);
+		LOG(ERR) << rx_smpl_buf[0]->str_status();
 		return 0;
 	}

-	// Receive samples from the usrp until we have enough
-	while (rx_smpl_buf->avail_smpls(timestamp) < len) {
-		size_t num_smpls = usrp_dev->get_device()->recv(
-					(void*)pkt_buf,
-					rx_spp,
-					metadata,
-					uhd::io_type_t::COMPLEX_INT16,
-					uhd::device::RECV_MODE_ONE_PACKET);
+	std::vector<std::vector<std::complex<short> > > bufs(
+		NUM_RX_CHANS, std::vector<std::complex<short> >(rx_spp));
+	std::vector<std::complex<short> *> buf_ptrs;
+	for (int i = 0; i < bufs.size(); i++)
+		buf_ptrs.push_back(&bufs[i].front());

+	// Receive samples from the usrp until we have enough
+	while (rx_smpl_buf[0]->avail_smpls(timestamp) < len) {
+		size_t num_smpls = rx_stream->recv(buf_ptrs, rx_spp,
+						   metadata, 0.1, true);
 		rx_pkt_cnt++;

 		// Check for errors 
@@ -653,39 +835,45 @@ int uhd_device::readSamples(short *buf, int len, bool *overrun,
 		case ERROR_TIMING:
 			restart(prev_ts);
 		case ERROR_UNHANDLED:
+			LOG(ALERT) << "UHD: Unhandled error";
 			continue;
 		}

-
 		ts = metadata.time_spec;
-		LOG(DEBUG) << "Received timestamp = " << ts.get_real_secs();
+		LOG(DEBUG) << "Received " << num_smpls << " samples "
+			   << "with timestamp = " << ts.get_real_secs();

-		rc = rx_smpl_buf->write(pkt_buf,
-					num_smpls,
-					metadata.time_spec);
-
-		// Continue on local overrun, exit on other errors
-		if ((rc < 0)) {
-			LOG(ERR) << rx_smpl_buf->str_code(rc);
-			LOG(ERR) << rx_smpl_buf->str_status();
-			if (rc != smpl_buf::ERROR_OVERFLOW)
-				return 0;
+		for (int i = 0; i < NUM_RX_CHANS; i++) {
+			rc = rx_smpl_buf[i]->write((short *) &bufs[i].front(),
+						   num_smpls,
+						   metadata.time_spec);
+                        
+			// Continue on local overrun, exit on other errors
+			if ((rc < 0)) {
+				LOG(ERR) << rx_smpl_buf[i]->str_code(rc);
+				LOG(ERR) << rx_smpl_buf[i]->str_status();
+				if (rc != smpl_buf::ERROR_OVERFLOW)
+					return 0;
+			}
 		}
 	}

 	// We have enough samples
-	rc = rx_smpl_buf->read(buf, len, timestamp);
-	if ((rc < 0) || (rc != len)) {
-		LOG(ERR) << rx_smpl_buf->str_code(rc);
-		LOG(ERR) << rx_smpl_buf->str_status();
-		return 0;
+	for (int i = 0; i < NUM_RX_CHANS; i++) {
+		rc = rx_smpl_buf[i]->read(buf[i], len, timestamp);
+		if ((rc < 0) || (rc != len)) {
+			LOG(ERR) << rx_smpl_buf[i]->str_code(rc);
+			LOG(ERR) << rx_smpl_buf[i]->str_status();
+			return 0;
+		}
 	}

 	return len;
 }

-int uhd_device::writeSamples(short *buf, int len, bool *underrun,
-			unsigned long long timestamp,bool isControl)
+int uhd_device::writeSamples(short **buf, int chans, int len,
+			     TIMESTAMP timestamp, bool *underrun,
+			     bool isControl)
 {
 	uhd::tx_metadata_t metadata;
 	metadata.has_time_spec = true;
@@ -718,12 +906,11 @@ int uhd_device::writeSamples(short *buf, int len, bool *underrun,
 		}
 	}

-	size_t num_smpls = usrp_dev->get_device()->send(buf,
-					len,
-					metadata,
-					uhd::io_type_t::COMPLEX_INT16,
-					uhd::device::SEND_MODE_FULL_BUFF);
+	std::vector<short *> bufs(NUM_TX_CHANS);
+	for (int i = 0; i < NUM_TX_CHANS; i++)
+		bufs[i] = buf[i];

+	size_t num_smpls = tx_stream->send(bufs, len, metadata);
 	if (num_smpls != (unsigned) len) {
 		LOG(ALERT) << "UHD: Device send timed out";
 		LOG(ALERT) << "UHD: Version " << uhd::get_version_string();
@@ -736,24 +923,33 @@ int uhd_device::writeSamples(short *buf, int len, bool *underrun,

 bool uhd_device::updateAlignment(TIMESTAMP timestamp)
 {
-	aligned = false;
 	return true;
 }

-bool uhd_device::setTxFreq(double wFreq)
+bool uhd_device::setTxFreq(double wFreq, int chan)
 {
-	uhd::tune_result_t tr = usrp_dev->set_tx_freq(wFreq);
+	if (chan >= NUM_TX_CHANS) {
+		LOG(ALERT) << "Attempting to tune non-existent channel";
+		return false;
+	}
+
+	uhd::tune_result_t tr = usrp_dev->set_tx_freq(wFreq, chan);
 	LOG(INFO) << "\n" << tr.to_pp_string();
-	tx_freq = usrp_dev->get_tx_freq();
+	tx_freq[chan] = usrp_dev->get_tx_freq(chan);

 	return true;
 }

-bool uhd_device::setRxFreq(double wFreq)
+bool uhd_device::setRxFreq(double wFreq, int chan)
 {
-	uhd::tune_result_t tr = usrp_dev->set_rx_freq(wFreq);
+	if (chan >= NUM_RX_CHANS) {
+		LOG(ALERT) << "Attempting to tune non-existent channel";
+		return false;
+	}
+
+	uhd::tune_result_t tr = usrp_dev->set_rx_freq(wFreq, chan);
 	LOG(INFO) << "\n" << tr.to_pp_string();
-	rx_freq = usrp_dev->get_rx_freq();
+	rx_freq[chan] = usrp_dev->get_rx_freq(chan);

 	return true;
 }
@@ -888,7 +1084,7 @@ ssize_t smpl_buf::read(void *buf, size_t len, TIMESTAMP timestamp)
 		num_smpls = len;

 	// Starting index
-	size_t read_start = data_start + (timestamp - time_start);
+	size_t read_start = (data_start + (timestamp - time_start)) % buf_len;

 	// Read it
 	if (read_start + num_smpls < buf_len) {
@@ -986,7 +1182,7 @@ std::string smpl_buf::str_code(ssize_t code)
 	}
 }

-RadioDevice *RadioDevice::make(double smpl_rt, bool skip_rx)
+RadioDevice *RadioDevice::make(int sps, bool skip_rx)
 {
-	return new uhd_device(smpl_rt, skip_rx);
+	return new uhd_device(sps, skip_rx);
 }
--- a/Transceiver52M/USRPDevice.cpp
+++ b/Transceiver52M/USRPDevice.cpp
@@ -59,11 +59,11 @@ const dboardConfigType dboardConfig = TXA_RXB;

 const double USRPDevice::masterClockRate = 52.0e6;

-USRPDevice::USRPDevice (double _desiredSampleRate, bool skipRx)
+USRPDevice::USRPDevice(int sps, bool skipRx)
  : skipRx(skipRx)
 {
  LOG(INFO) << "creating USRP device...";
-  decimRate = (unsigned int) round(masterClockRate/_desiredSampleRate);
+  decimRate = (unsigned int) round(masterClockRate/((GSMRATE) * (double) sps));
  actualSampleRate = masterClockRate/decimRate;
  rxGain = 0;

@@ -75,7 +75,7 @@ USRPDevice::USRPDevice (double _desiredSampleRate, bool skipRx)
 #endif
 }

-bool USRPDevice::open(const std::string &)
+int USRPDevice::open(const std::string &)
 {
  writeLock.unlock();

@@ -97,7 +97,7 @@ bool USRPDevice::open(const std::string &)
  catch(...) {
    LOG(ALERT) << "make failed on Rx";
    m_uRx.reset();
-    return false;
+    return -1;
  }

  if (m_uRx->fpga_master_clock_freq() != masterClockRate)
@@ -105,7 +105,7 @@ bool USRPDevice::open(const std::string &)
    LOG(ALERT) << "WRONG FPGA clock freq = " << m_uRx->fpga_master_clock_freq()
               << ", desired clock freq = " << masterClockRate;
    m_uRx.reset();
-    return false;
+    return -1;
  }
  }

@@ -120,7 +120,7 @@ bool USRPDevice::open(const std::string &)
  catch(...) {
    LOG(ALERT) << "make failed on Tx";
    m_uTx.reset();
-    return false;
+    return -1;
  }

  if (m_uTx->fpga_master_clock_freq() != masterClockRate)
@@ -128,7 +128,7 @@ bool USRPDevice::open(const std::string &)
    LOG(ALERT) << "WRONG FPGA clock freq = " << m_uTx->fpga_master_clock_freq()
               << ", desired clock freq = " << masterClockRate;
    m_uTx.reset();
-    return false;
+    return -1;
  }

  if (!skipRx) m_uRx->stop();
@@ -165,7 +165,7 @@ bool USRPDevice::open(const std::string &)
  samplesWritten = 0;
  started = false;
  
-  return true;
+  return NORMAL;
 }


@@ -556,7 +556,7 @@ bool USRPDevice::setTxFreq(double wFreq) { return true;};
 bool USRPDevice::setRxFreq(double wFreq) { return true;};
 #endif

-RadioDevice *RadioDevice::make(double desiredSampleRate, bool skipRx)
+RadioDevice *RadioDevice::make(int sps, bool skipRx)
 {
-	return new USRPDevice(desiredSampleRate, skipRx);
+	return new USRPDevice(sps, skipRx);
 }
--- a/Transceiver52M/USRPDevice.h
+++ b/Transceiver52M/USRPDevice.h
@@ -112,10 +112,10 @@ private:
 public:

  /** Object constructor */
-  USRPDevice (double _desiredSampleRate, bool skipRx);
+  USRPDevice(int sps, bool skipRx);

  /** Instantiate the USRP */
-  bool open(const std::string &);
+  int open(const std::string &);

  /** Start the USRP */
  bool start();
@@ -126,8 +126,7 @@ private:
  /** Set priority not supported */
  void setPriority() { return; }

-  /** Only USB bus supported */
-  busType getBus() { return USB; }
+  enum TxWindowType getWindowType() { return TX_WINDOW_USRP1; }

  /**
 	Read samples from the USRP.
--- a/Transceiver52M/USRPping.cpp
+++ b/Transceiver52M/USRPping.cpp
@@ -41,7 +41,7 @@ int main(int argc, char *argv[]) {
  else gLogInit("DEBUG");
  //if (argc>2) gSetLogFile(argv[2]);

-  RadioDevice *usrp = RadioDevice::make(52.0e6/192.0);
+  RadioDevice *usrp = RadioDevice::make(52.0e6/192.0, 1);

  usrp->open("");

--- a/Transceiver52M/multiTRX.cpp
+++ b/Transceiver52M/multiTRX.cpp
@@ -0,0 +1,120 @@
+/*
+ * Copyright 2012  Thomas Tsou <ttsou@vt.edu>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ * See the COPYING file in the main directory for details.
+ */
+
+#include <time.h>
+#include <signal.h>
+
+#include <GSMCommon.h>
+#include <Logger.h>
+#include <Configuration.h>
+
+#include "Transceiver.h"
+#include "radioDevice.h"
+
+ConfigurationTable gConfig("/etc/OpenBTS/OpenBTS.db");
+
+volatile bool gbShutdown = false;
+
+int Transceiver::mTSC = -1;
+
+static void sigHandler(int signum)
+{
+	LOG(NOTICE) << "Received shutdown signal";
+	gbShutdown = true;
+}
+
+static int setupSignals()
+{
+	struct sigaction action;
+
+	action.sa_handler = sigHandler;
+	sigemptyset(&action.sa_mask);
+	action.sa_flags = 0;
+
+	if (sigaction(SIGINT, &action, NULL) < 0)
+		return -1;
+	if (sigaction(SIGTERM, &action, NULL) < 0)
+		return -1;
+
+	return 0;
+}
+
+int main(int argc, char *argv[])
+{
+	int numARFCN = 1;
+
+	if (argc > 1) {
+		numARFCN = atoi(argv[1]);
+		if (numARFCN > CHAN_MAX) {
+			LOG(ALERT) << numARFCN  << " channels not supported "
+						<< " with with current build";
+			exit(-1);
+		}
+	}
+
+	gLogInit("transceiver", gConfig.getStr("Log.Level").c_str(), LOG_LOCAL7);
+	srandom(time(NULL));
+
+	if (setupSignals() < 0) {
+		LOG(ERR) << "Failed to setup signal handlers, exiting...";
+		exit(-1);
+	}
+
+	RadioDevice *device = RadioDevice::make(SAMPSPERSYM);
+	int radioType = device->open("");
+	if (radioType < 0) {
+		LOG(ALERT) << "Failed to open device, exiting...";
+		return EXIT_FAILURE;
+	}
+
+	RadioInterface *radio;
+	switch (radioType) {
+	case RadioDevice::NORMAL:
+		radio = new RadioInterface(device, numARFCN);
+		break;
+	case RadioDevice::RESAMP:
+	default:
+		LOG(ALERT) << "Unsupported configuration";
+		return EXIT_FAILURE;
+	}
+
+	DriveLoop *drive = new DriveLoop(5700, "127.0.0.1", radio, numARFCN, 0);
+
+	Transceiver *trx[CHAN_MAX];
+	bool primary = true;
+	for (int i = 0; i < numARFCN; i++) {
+		trx[i] = new Transceiver(5700 + 2 * i, "127.0.0.1",
+					 drive, radio, SAMPSPERSYM,
+					 i, primary);
+		trx[i]->start();
+		primary = false;
+	}
+
+	while (!gbShutdown)
+		sleep(1);
+
+	LOG(NOTICE) << "Shutting down transceivers...";
+	for (int i = 0; i < numARFCN; i++)
+		trx[i]->shutdown();
+
+	for (int i = 0; i < numARFCN; i++)
+		delete trx[i];
+	delete drive;
+	delete radio;
+	delete device;
+}
--- a/Transceiver52M/radioDevice.h
+++ b/Transceiver52M/radioDevice.h
@@ -21,6 +21,8 @@
 #include "config.h"
 #endif

+#define GSMRATE       1625e3/6
+
 /** a 64-bit virtual timestamp for radio data */
 typedef unsigned long long TIMESTAMP;

@@ -29,12 +31,17 @@ class RadioDevice {

  public:
  /* Available transport bus types */
-  enum busType { USB, NET };
+  enum TxWindowType { TX_WINDOW_USRP1, TX_WINDOW_FIXED };

-  static RadioDevice *make(double desiredSampleRate, bool skipRx = false);
+  /* Radio interface types */
+  enum RadioInterfaceType { NORMAL, RESAMP };
+
+  static RadioDevice *make(int sps, bool skipRx = false);
+
+  virtual ~RadioDevice() {};

  /** Initialize the USRP */
-  virtual bool open(const std::string &args)=0;
+  virtual int open(const std::string &args)=0;

  /** Start the USRP */
  virtual bool start()=0;
@@ -42,8 +49,8 @@ class RadioDevice {
  /** Stop the USRP */
  virtual bool stop()=0;

-  /** Get the bus type */
-  virtual enum busType getBus()=0;
+  /** Get the Tx window type */
+  virtual enum TxWindowType getWindowType()=0;

  /** Enable thread priority */
  virtual void setPriority()=0;
@@ -58,10 +65,9 @@ class RadioDevice {
 	@param RSSI The received signal strength of the read result
 	@return The number of samples actually read
  */
-  virtual int readSamples(short *buf, int len, bool *overrun, 
-		   TIMESTAMP timestamp = 0xffffffff,
-		   bool *underrun = 0,
-		   unsigned *RSSI = 0)=0;
+  virtual int readSamples(short **buf, int chans, int len, TIMESTAMP timestamp,
+                          bool *overrun = NULL, bool *underrun = NULL,
+                          unsigned *RSSI = NULL)=0;
  /**
        Write samples to the radio.
        @param buf Contains the data to be written.
@@ -71,18 +77,17 @@ class RadioDevice {
        @param isControl Set if data is a control packet, e.g. a ping command
        @return The number of samples actually written
  */
-  virtual int writeSamples(short *buf, int len, bool *underrun, 
-		    TIMESTAMP timestamp,
-		    bool isControl=false)=0;
+  virtual int writeSamples(short **buf, int chans, int len, TIMESTAMP timestamp,
+                           bool *underrun = NULL, bool isControl = false)=0;
 
  /** Update the alignment between the read and write timestamps */
  virtual bool updateAlignment(TIMESTAMP timestamp)=0;
  
  /** Set the transmitter frequency */
-  virtual bool setTxFreq(double wFreq)=0;
+  virtual bool setTxFreq(double wFreq, int chan = 0)=0;

  /** Set the receiver frequency */
-  virtual bool setRxFreq(double wFreq)=0;
+  virtual bool setRxFreq(double wFreq, int chan = 0)=0;

  /** Returns the starting write Timestamp*/
  virtual TIMESTAMP initialWriteTimestamp(void)=0;
@@ -97,10 +102,10 @@ class RadioDevice {
  virtual double fullScaleOutputValue()=0;

  /** sets the receive chan gain, returns the gain setting **/
-  virtual double setRxGain(double dB)=0;
+  virtual double setRxGain(double dB, int chan = 0)=0;

  /** gets the current receive gain **/
-  virtual double getRxGain(void)=0;
+  virtual double getRxGain(int chan = 0)=0;

  /** return maximum Rx Gain **/
  virtual double maxRxGain(void) = 0;
@@ -109,7 +114,7 @@ class RadioDevice {
  virtual double minRxGain(void) = 0;

  /** sets the transmit chan gain, returns the gain setting **/
-  virtual double setTxGain(double dB)=0;
+  virtual double setTxGain(double dB, int chan = 0)=0;

  /** return maximum Tx Gain **/
  virtual double maxTxGain(void) = 0;
@@ -117,13 +122,18 @@ class RadioDevice {
  /** return minimum Tx Gain **/
  virtual double minTxGain(void) = 0;

+  /** set and return antennas selection **/
+  virtual void setTxAntenna(std::string &name) = 0;
+  virtual void setRxAntenna(std::string &name) = 0;
+  virtual std::string getRxAntenna() = 0;
+  virtual std::string getTxAntenna() = 0;
+
  /** Return internal status values */
-  virtual double getTxFreq()=0;
-  virtual double getRxFreq()=0;
+  virtual double getTxFreq(int chan = 0)=0;
+  virtual double getRxFreq(int chan = 0)=0;
  virtual double getSampleRate()=0;
  virtual double numberRead()=0;
  virtual double numberWritten()=0;
-
 };

 #endif
--- a/Transceiver52M/radioIO.cpp
+++ b/Transceiver52M/radioIO.cpp
@@ -1,91 +0,0 @@
-/*
- * Radio device I/O interface
- * Written by Thomas Tsou <ttsou@vt.edu>
- *
- * Copyright 2011 Free Software Foundation, Inc.
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU Affero General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU Affero General Public License for more details.
- *
- * You should have received a copy of the GNU Affero General Public License
- * along with this program.  If not, see <http://www.gnu.org/licenses/>.
- * See the COPYING file in the main directory for details.
- */
-
-#include <radioInterface.h>
-#include <Logger.h>
-
-/* Device side buffers */
-static short rx_buf[OUTCHUNK * 2 * 2];
-static short tx_buf[INCHUNK * 2 * 2];
-
-/* Complex float to short conversion */
-static int float_to_short(short *shrt_out, float *flt_in, int num)
-{
-	int i;
-
-	for (i = 0; i < num; i++) {
-		shrt_out[2 * i + 0] = flt_in[2 * i + 0];
-		shrt_out[2 * i + 1] = flt_in[2 * i + 1];
-	}
-
-	return i;
-}
-
-/* Comlpex short to float conversion */
-static int short_to_float(float *flt_out, short *shrt_in, int num)
-{
-	int i;
-
-	for (i = 0; i < num; i++) {
-		flt_out[2 * i + 0] = shrt_in[2 * i + 0];
-		flt_out[2 * i + 1] = shrt_in[2 * i + 1];
-	}
-
-	return i;
-}
-
-/* Receive a timestamped chunk from the device */ 
-void RadioInterface::pullBuffer()
-{
-	bool local_underrun;
-
-	/* Read samples. Fail if we don't get what we want. */
-	int num_rd = mRadio->readSamples(rx_buf, OUTCHUNK, &overrun,
-					    readTimestamp, &local_underrun);
-
-	LOG(DEBUG) << "Rx read " << num_rd << " samples from device";
-	assert(num_rd == OUTCHUNK);
-
-	underrun |= local_underrun;
-	readTimestamp += (TIMESTAMP) num_rd;
-
-	short_to_float(rcvBuffer + 2 * rcvCursor, rx_buf, num_rd);
-	rcvCursor += num_rd;
-}
-
-/* Send timestamped chunk to the device with arbitrary size */ 
-void RadioInterface::pushBuffer()
-{
-	if (sendCursor < INCHUNK)
-		return;
-
-	float_to_short(tx_buf, sendBuffer, sendCursor);
-
-	/* Write samples. Fail if we don't get what we want. */
-	int num_smpls = mRadio->writeSamples(tx_buf,
-					     sendCursor,
-					     &underrun,
-					     writeTimestamp);
-	assert(num_smpls == sendCursor);
-
-	writeTimestamp += (TIMESTAMP) num_smpls;
-	sendCursor = 0;
-}
--- a/Transceiver52M/radioIOResamp.cpp
+++ b/Transceiver52M/radioIOResamp.cpp
@@ -1,324 +0,0 @@
-/*
- * Radio device interface with sample rate conversion
- * Written by Thomas Tsou <ttsou@vt.edu>
- *
- * Copyright 2011 Free Software Foundation, Inc.
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU Affero General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU Affero General Public License for more details.
- *
- * You should have received a copy of the GNU Affero General Public License
- * along with this program.  If not, see <http://www.gnu.org/licenses/>.
- * See the COPYING file in the main directory for details.
- */
-
-#include <radioInterface.h>
-#include <Logger.h>
-
-/* New chunk sizes for resampled rate */
-#ifdef INCHUNK
-  #undef INCHUNK
-#endif
-#ifdef OUTCHUNK
-  #undef OUTCHUNK
-#endif
-
-/* Resampling parameters */
-#define INRATE       65 * SAMPSPERSYM
-#define INHISTORY    INRATE * 2
-#define INCHUNK      INRATE * 9
-
-#define OUTRATE      96 * SAMPSPERSYM
-#define OUTHISTORY   OUTRATE * 2
-#define OUTCHUNK     OUTRATE * 9
-
-/* Resampler low pass filters */
-signalVector *tx_lpf = 0;
-signalVector *rx_lpf = 0;
-
-/* Resampler history */
-signalVector *tx_hist = 0;
-signalVector *rx_hist = 0;
-
-/* Resampler input buffer */
-signalVector *tx_vec = 0;
-signalVector *rx_vec = 0;
-
-/*
- * High rate (device facing) buffers
- *
- * Transmit side samples are pushed after each burst so accomodate
- * a resampled burst plus up to a chunk left over from the previous
- * resampling operation.
- *
- * Receive side samples always pulled with a fixed size.
- */
-short tx_buf[INCHUNK * 2 * 4];
-short rx_buf[OUTCHUNK * 2 * 2];
-
-/* 
- * Utilities and Conversions 
- *
- * Manipulate signal vectors dynamically for two reasons. For one,
- * it's simpler. And two, it doesn't make any reasonable difference
- * relative to the high overhead generated by the resampling.
- */
-
-/* Concatenate signal vectors. Deallocate input vectors. */
-signalVector *concat(signalVector *a, signalVector *b)
-{
-	signalVector *vec = new signalVector(*a, *b);
-	delete a;
-	delete b;
-
-	return vec;
-}
-
-/* Segment a signal vector. Deallocate the input vector. */
-signalVector *segment(signalVector *a, int indx, int sz)
-{
-	signalVector *vec = new signalVector(sz);
-	a->segmentCopyTo(*vec, indx, sz);
-	delete a;
-
-	return vec;
-}
-
-/* Create a new signal vector from a short array. */
-signalVector *short_to_sigvec(short *smpls, size_t sz)
-{
-	int i;
-	signalVector *vec = new signalVector(sz);
-	signalVector::iterator itr = vec->begin();
-
-	for (i = 0; i < sz; i++) {
-		*itr++ = Complex<float>(smpls[2 * i + 0], smpls[2 * i + 1]);
-	}
-
-	return vec;
-}
-
-/* Convert and deallocate a signal vector into a short array. */
-int sigvec_to_short(signalVector *vec, short *smpls)
-{
-	int i;
-	signalVector::iterator itr = vec->begin();
-
-	for (i = 0; i < vec->size(); i++) {
-		smpls[2 * i + 0] = itr->real();
-		smpls[2 * i + 1] = itr->imag();
-		itr++;
-	}
-	delete vec;
-
-	return i;
-}
-
-/* Create a new signal vector from a float array. */
-signalVector *float_to_sigvec(float *smpls, int sz)
-{
-	int i;
-	signalVector *vec = new signalVector(sz);
-	signalVector::iterator itr = vec->begin();
-
-	for (i = 0; i < sz; i++) {
-		*itr++ = Complex<float>(smpls[2 * i + 0], smpls[2 * i + 1]);
-	}
-
-	return vec;
-}
-
-/* Convert and deallocate a signal vector into a float array. */
-int sigvec_to_float(signalVector *vec, float *smpls)
-{
-	int i;
-	signalVector::iterator itr = vec->begin();
-
-	for (i = 0; i < vec->size(); i++) {
-		smpls[2 * i + 0] = itr->real();
-		smpls[2 * i + 1] = itr->imag();
-		itr++;
-	}
-	delete vec;
-
-	return i;
-}
-
-/* Initialize resampling signal vectors */
-void init_resampler(signalVector **lpf,
-	   	    signalVector **buf,
-		    signalVector **hist,
-		    int tx)
-{
-	int P, Q, taps, hist_len;
-	float cutoff_freq;
-
-	if (tx) {
-		LOG(INFO) << "Initializing Tx resampler";
-		P = OUTRATE;
-		Q = INRATE;
-		taps = 651;
-		hist_len = INHISTORY;
-	} else {
-		LOG(INFO) << "Initializing Rx resampler";
-		P = INRATE;
-		Q = OUTRATE;
-		taps = 961;
-		hist_len = OUTHISTORY;
-	}
-
-	if (!*lpf) {
-		cutoff_freq = (P < Q) ? (1.0/(float) Q) : (1.0/(float) P);
-		*lpf = createLPF(cutoff_freq, taps, P);
-	}
-
-	if (!*buf) {
-		*buf = new signalVector();
-	}
-
-	if (!*hist);
-		*hist = new signalVector(hist_len);
-}
-
-/* Resample a signal vector
- *
- * The input vector is deallocated and the pointer returned with a vector
- * of any unconverted samples.
- */
-signalVector *resmpl_sigvec(signalVector *hist, signalVector **vec,
-			    signalVector *lpf, double in_rate,
-			    double out_rate, int chunk_sz)
-{
-	signalVector *resamp_vec;
-	int num_chunks = (*vec)->size() / chunk_sz;
-
-	/* Truncate to a chunk multiple */
-	signalVector trunc_vec(num_chunks * chunk_sz);
-	(*vec)->segmentCopyTo(trunc_vec, 0, num_chunks * chunk_sz);
-
-	/* Update sample buffer with remainder */
-	*vec = segment(*vec, trunc_vec.size(), (*vec)->size() - trunc_vec.size());
-
-	/* Add history and resample */
-	signalVector input_vec(*hist, trunc_vec);
-	resamp_vec = polyphaseResampleVector(input_vec, in_rate,
-					     out_rate, lpf);
-
-	/* Update history */
-	trunc_vec.segmentCopyTo(*hist, trunc_vec.size() - hist->size(),
-				hist->size());
-	return resamp_vec;
-}
-
-/* Wrapper for receive-side integer-to-float array resampling */
- int rx_resmpl_int_flt(float *smpls_out, short *smpls_in, int num_smpls)
-{
-	int num_resmpld, num_chunks;
-	signalVector *convert_vec, *resamp_vec, *trunc_vec;
-
-	if (!rx_lpf || !rx_vec || !rx_hist)
-		init_resampler(&rx_lpf, &rx_vec, &rx_hist, false);
-
-	/* Convert and add samples to the receive buffer */
-	convert_vec = short_to_sigvec(smpls_in, num_smpls);
-	rx_vec = concat(rx_vec, convert_vec);
-
-	num_chunks = rx_vec->size() / OUTCHUNK;
-	if (num_chunks < 1)
-		return 0;
-
-	/* Resample */ 
-	resamp_vec = resmpl_sigvec(rx_hist, &rx_vec, rx_lpf,
-				   INRATE, OUTRATE, OUTCHUNK);
-	/* Truncate */
-	trunc_vec = segment(resamp_vec, INHISTORY,
-                            resamp_vec->size() - INHISTORY);
-	/* Convert */
-	num_resmpld = sigvec_to_float(trunc_vec, smpls_out);
-
-	return num_resmpld; 
-}
-
-/* Wrapper for transmit-side float-to-int array resampling */
-int tx_resmpl_flt_int(short *smpls_out, float *smpls_in, int num_smpls)
-{
-	int num_resmpl, num_chunks;
-	signalVector *convert_vec, *resamp_vec;
-
-	if (!tx_lpf || !tx_vec || !tx_hist)
-		init_resampler(&tx_lpf, &tx_vec, &tx_hist, true);
-
-	/* Convert and add samples to the transmit buffer */
-	convert_vec = float_to_sigvec(smpls_in, num_smpls);
-	tx_vec = concat(tx_vec, convert_vec);
-
-	num_chunks = tx_vec->size() / INCHUNK;
-	if (num_chunks < 1)
-		return 0;
-
-	/* Resample and convert to an integer array */
-	resamp_vec = resmpl_sigvec(tx_hist, &tx_vec, tx_lpf,
-				   OUTRATE, INRATE, INCHUNK);
-	num_resmpl = sigvec_to_short(resamp_vec, smpls_out);
-
-	return num_resmpl; 
-}
-
-/* Receive a timestamped chunk from the device */ 
-void RadioInterface::pullBuffer()
-{
-	int num_cv, num_rd;
-	bool local_underrun;
-
-	/* Read samples. Fail if we don't get what we want. */
-	num_rd = mRadio->readSamples(rx_buf, OUTCHUNK, &overrun,
-				     readTimestamp, &local_underrun);
-
-	LOG(DEBUG) << "Rx read " << num_rd << " samples from device";
-	assert(num_rd == OUTCHUNK);
-
-	underrun |= local_underrun;
-	readTimestamp += (TIMESTAMP) num_rd;
-
-	/* Convert and resample */
-	num_cv = rx_resmpl_int_flt(rcvBuffer + 2 * rcvCursor,
-				   rx_buf, num_rd);
-
-	LOG(DEBUG) << "Rx read " << num_cv << " samples from resampler";
-
-	rcvCursor += num_cv;
-}
-
-/* Send a timestamped chunk to the device */ 
-void RadioInterface::pushBuffer()
-{
-	int num_cv, num_wr;
-
-	if (sendCursor < INCHUNK)
-		return;
-
-	LOG(DEBUG) << "Tx wrote " << sendCursor << " samples to resampler";
-
-	/* Resample and convert */
-	num_cv = tx_resmpl_flt_int(tx_buf, sendBuffer, sendCursor);
-	assert(num_cv > sendCursor);
-
-	/* Write samples. Fail if we don't get what we want. */
-	num_wr = mRadio->writeSamples(tx_buf + OUTHISTORY * 2,
-				      num_cv - OUTHISTORY,
-				      &underrun,
-				      writeTimestamp);
-
-	LOG(DEBUG) << "Tx wrote " << num_wr << " samples to device";
-	assert(num_wr == num_wr);
-
-	writeTimestamp += (TIMESTAMP) num_wr;
-	sendCursor = 0;
-}
--- a/Transceiver52M/radioInterface.cpp
+++ b/Transceiver52M/radioInterface.cpp
@@ -1,5 +1,5 @@
 /*
-* Copyright 2008, 2009 Free Software Foundation, Inc.
+* Copyright 2008, 2009, 2012 Free Software Foundation, Inc.
 *
 * This software is distributed under the terms of the GNU Affero Public License.
 * See the COPYING file in the main directory for details.
@@ -27,23 +27,53 @@

 bool started = false;

+/* Device side buffers */
+static short *rx_buf[CHAN_MAX];
+static short *tx_buf[CHAN_MAX];
+
+/* Complex float to short conversion */
+static void floatToShort(short *out, float *in, int num)
+{
+  for (int i = 0; i < num; i++) {
+    out[2 * i + 0] = (short) in[2 * i + 0];
+    out[2 * i + 1] = (short) in[2 * i + 1];
+  }
+}
+
+/* Complex short to float conversion */
+static void shortToFloat(float *out, short *in, int num)
+{
+  for (int i = 0; i < num; i++) {
+    out[2 * i + 0] = (float) in[2 * i + 0];
+    out[2 * i + 1] = (float) in[2 * i + 1];
+  }
+}
+
 RadioInterface::RadioInterface(RadioDevice *wRadio,
-			       int wReceiveOffset,
-			       int wRadioOversampling,
-			       int wTransceiverOversampling,
+			       int wChanM,
+			       int wSPS,
+                               int wReceiveOffset,
 			       GSM::Time wStartTime)
-  : underrun(false), sendCursor(0), rcvCursor(0), mOn(false),
-    mRadio(wRadio), receiveOffset(wReceiveOffset),
-    samplesPerSymbol(wRadioOversampling), powerScaling(1.0),
-    loadTest(false)
+  : mChanM(wChanM), underrun(false), sendCursor(0), rcvCursor(0), mOn(false),
+    mRadio(wRadio), receiveOffset(wReceiveOffset), samplesPerSymbol(wSPS),
+    powerScaling(1.0), loadTest(false)
 {
  mClock.set(wStartTime);
 }

+RadioInterface::~RadioInterface(void)
+{
+  if (mOn) {
+    mRadio->stop();
+    close();

-RadioInterface::~RadioInterface(void) {
-  if (rcvBuffer!=NULL) delete rcvBuffer;
-  //mReceiveFIFO.clear();
+    for (int i = 0; i < mChanM; i++) {
+      if (rcvBuffer[i] != NULL)
+        delete rcvBuffer[i];
+      if (sendBuffer[i] != NULL)
+        delete sendBuffer[i];
+    }
+  }
 }

 double RadioInterface::fullScaleInputValue(void) {
@@ -55,11 +85,11 @@ double RadioInterface::fullScaleOutputValue(void) {
 }


-void RadioInterface::setPowerAttenuation(double atten)
+void RadioInterface::setPowerAttenuation(double atten, int chan)
 {
  double rfGain, digAtten;

-  rfGain = mRadio->setTxGain(mRadio->maxTxGain() - atten);
+  rfGain = mRadio->setTxGain(mRadio->maxTxGain() - atten, chan);
  digAtten = atten - mRadio->maxTxGain() + rfGain;

  if (digAtten < 1.0)
@@ -90,53 +120,75 @@ int RadioInterface::radioifyVector(signalVector &wVector,
  return wVector.size();
 }

-int RadioInterface::unRadioifyVector(float *floatVector,
-				     signalVector& newVector)
+int RadioInterface::unRadioifyVector(float *floatVector, int offset,
+				     signalVector &newVector)
 {
  int i;
  signalVector::iterator itr = newVector.begin();

  for (i = 0; i < newVector.size(); i++) {
-    *itr++ = Complex<float>(floatVector[2 * i + 0],
-			    floatVector[2 * i + 1]);
+    *itr++ = Complex<float>(floatVector[offset + 2 * i + 0],
+			    floatVector[offset + 2 * i + 1]);
  }

  return newVector.size();
 }

-bool RadioInterface::tuneTx(double freq)
+bool RadioInterface::tuneTx(double freq, int chan)
 {
-  return mRadio->setTxFreq(freq);
+  return mRadio->setTxFreq(freq, chan);
 }

-bool RadioInterface::tuneRx(double freq)
+bool RadioInterface::tuneRx(double freq, int chan)
 {
-  return mRadio->setRxFreq(freq);
+  return mRadio->setRxFreq(freq, chan);
 }


-void RadioInterface::start()
+bool RadioInterface::start()
 {
-  LOG(INFO) << "starting radio interface...";
-  mAlignRadioServiceLoopThread.start((void * (*)(void*))AlignRadioServiceLoopAdapter,
-                                     (void*)this);
+  int i;
+
+  if (mOn)
+    return false;
+
+  mOn = true;
+#ifdef USRP1
+  mAlignRadioServiceLoopThread = new Thread(32768);
+  mAlignRadioServiceLoopThread->start((void * (*)(void*))AlignRadioServiceLoopAdapter,
+                                      (void*)this);
+#endif
  writeTimestamp = mRadio->initialWriteTimestamp();
  readTimestamp = mRadio->initialReadTimestamp();
+  for (i = 0; i < mChanM; i++) {
+    sendBuffer[i] = new float[8*2*INCHUNK];
+    rcvBuffer[i] = new float[8*2*OUTCHUNK];
+  }
+
+  /* Init I/O specific variables if applicable */ 
+  init();
+
  mRadio->start(); 
  LOG(DEBUG) << "Radio started";
  mRadio->updateAlignment(writeTimestamp-10000); 
  mRadio->updateAlignment(writeTimestamp-10000);

-  sendBuffer = new float[2*2*INCHUNK*samplesPerSymbol];
-  rcvBuffer = new float[2*2*OUTCHUNK*samplesPerSymbol];
- 
-  mOn = true;
-
+  return true;
 }

+bool RadioInterface::stop()
+{
+  if (!mOn)
+    return false;
+
+  mOn = false;
+  mRadio->stop();
+}
+
+#ifdef USRP1
 void *AlignRadioServiceLoopAdapter(RadioInterface *radioInterface)
 {
-  while (1) {
+  while (radioInterface->on()) {
    radioInterface->alignRadio();
    pthread_testcancel();
  }
@@ -147,23 +199,55 @@ void RadioInterface::alignRadio() {
  sleep(60);
  mRadio->updateAlignment(writeTimestamp+ (TIMESTAMP) 10000);
 }
+#endif

-void RadioInterface::driveTransmitRadio(signalVector &radioBurst, bool zeroBurst) {
+void RadioInterface::driveTransmitRadio(signalVector **radioBurst, bool *zeroBurst)
+{
+  int i;

-  if (!mOn) return;
+  if (!mOn)
+    return;

-  radioifyVector(radioBurst, sendBuffer + 2 * sendCursor, powerScaling, zeroBurst);
+  for (i = 0; i < mChanM; i++) {
+    radioifyVector(*radioBurst[i], sendBuffer[i] + 2 * sendCursor,
+                   powerScaling, zeroBurst[i]);
+  }

-  sendCursor += radioBurst.size();
+  /* 
+   * All bursts should be the same size since all transceivers are
+   * tied with a single clock in the radio interface.
+   */
+  sendCursor += radioBurst[0]->size();

  pushBuffer();
 }

-void RadioInterface::driveReceiveRadio() {
+static inline void shiftRxBuffers(float **buf, int offset, int len, int chanM)
+{
+  for (int i = 0; i < chanM; i++)
+      memmove(buf[i], buf[i] + offset, sizeof(float) * len);
+}

-  if (!mOn) return;
+void RadioInterface::loadVectors(unsigned tN, int samplesPerBurst,
+                                 int idx, GSM::Time rxClock)
+{
+  int i;

-  if (mReceiveFIFO.size() > 8) return;
+  for (i = 0; i < mChanM; i++) {
+    signalVector rxVector(samplesPerBurst);
+    unRadioifyVector(rcvBuffer[i], idx * 2, rxVector);
+    radioVector *rxBurst = new radioVector(rxVector, rxClock);
+    mReceiveFIFO[i].write(rxBurst);
+  }
+}
+
+void RadioInterface::driveReceiveRadio()
+{
+  if (!mOn)
+    return;
+
+  if (mReceiveFIFO[0].size() > 8)
+    return;

  pullBuffer();

@@ -173,71 +257,98 @@ void RadioInterface::driveReceiveRadio() {
  int rcvSz = rcvCursor;
  int readSz = 0;
  const int symbolsPerSlot = gSlotLen + 8;
+  int samplesPerBurst = (symbolsPerSlot + (tN % 4 == 0)) * samplesPerSymbol;

  // while there's enough data in receive buffer, form received 
  //    GSM bursts and pass up to Transceiver
  // Using the 157-156-156-156 symbols per timeslot format.
-  while (rcvSz > (symbolsPerSlot + (tN % 4 == 0))*samplesPerSymbol) {
-    signalVector rxVector((symbolsPerSlot + (tN % 4 == 0))*samplesPerSymbol);
-    unRadioifyVector(rcvBuffer+readSz*2,rxVector);
-    GSM::Time tmpTime = rcvClock;
+  while (rcvSz >= samplesPerBurst) { 
    if (rcvClock.FN() >= 0) {
-      //LOG(DEBUG) << "FN: " << rcvClock.FN();
-      radioVector *rxBurst = NULL;
-      if (!loadTest)
-        rxBurst = new radioVector(rxVector,tmpTime);
-      else {
-	if (tN % 4 == 0)
-	  rxBurst = new radioVector(*finalVec9,tmpTime);
-        else
-          rxBurst = new radioVector(*finalVec,tmpTime); 
-      }
-      mReceiveFIFO.put(rxBurst); 
+      loadVectors(tN, samplesPerBurst, readSz, rcvClock);
    }
-    mClock.incTN(); 
+
+    mClock.incTN();
    rcvClock.incTN();
-    //if (mReceiveFIFO.size() >= 16) mReceiveFIFO.wait(8);
-    //LOG(DEBUG) << "receiveFIFO: wrote radio vector at time: " << mClock.get() << ", new size: " << mReceiveFIFO.size() ;
-    readSz += (symbolsPerSlot+(tN % 4 == 0))*samplesPerSymbol;
-    rcvSz -= (symbolsPerSlot+(tN % 4 == 0))*samplesPerSymbol;
+
+    readSz += samplesPerBurst;
+    rcvSz -= samplesPerBurst;

    tN = rcvClock.TN();
+    samplesPerBurst = (symbolsPerSlot + (tN % 4 == 0)) * samplesPerSymbol;
  }

  if (readSz > 0) {
    rcvCursor -= readSz;
-    memmove(rcvBuffer,rcvBuffer+2*readSz,sizeof(float) * 2 * rcvCursor);
+    shiftRxBuffers(rcvBuffer, 2 * readSz, 2 * rcvCursor, mChanM);
  }
 }

-bool RadioInterface::isUnderrun()
-{
-  bool retVal = underrun;
-  underrun = false;
-
-  return retVal;
-}
-
-void RadioInterface::attach(RadioDevice *wRadio, int wRadioOversampling)
-{
-  if (!mOn) {
-    mRadio = wRadio;
-    mRadioOversampling = SAMPSPERSYM;
-  }
-}
-
-double RadioInterface::setRxGain(double dB)
+double RadioInterface::setRxGain(double dB, int chan)
 {
  if (mRadio)
-    return mRadio->setRxGain(dB);
+    return mRadio->setRxGain(dB, chan);
  else
    return -1;
 }

-double RadioInterface::getRxGain()
+double RadioInterface::getRxGain(int chan)
 {
  if (mRadio)
-    return mRadio->getRxGain();
+    return mRadio->getRxGain(chan);
  else
    return -1;
 }
+
+bool RadioInterface::init()
+{
+	for (int i = 0; i < CHAN_MAX; i++) {
+		rx_buf[i] = new short[2 * OUTCHUNK];
+		tx_buf[i] = new short[4 * 2 * INCHUNK];
+	}
+}
+
+void RadioInterface::close()
+{
+	for (int i = 0; i < CHAN_MAX; i++) {
+		delete rx_buf[i];
+		delete tx_buf[i];
+	}
+}
+
+/* Receive a timestamped chunk from the device */ 
+void RadioInterface::pullBuffer()
+{
+  bool local_underrun;
+
+  /* Read samples. Fail if we don't get what we want. */
+  int num_rd = mRadio->readSamples(rx_buf, mChanM, OUTCHUNK, readTimestamp);
+
+  LOG(DEBUG) << "Rx read " << num_rd << " samples from device";
+  assert(num_rd == OUTCHUNK);
+
+  underrun |= local_underrun;
+  readTimestamp += (TIMESTAMP) num_rd;
+
+  for (int i = 0; i < mChanM; i++)
+    shortToFloat(rcvBuffer[i] + 2 * rcvCursor, rx_buf[i], num_rd);
+
+  rcvCursor += num_rd;
+}
+
+/* Send timestamped chunk to the device with arbitrary size */ 
+void RadioInterface::pushBuffer()
+{
+  if (sendCursor < INCHUNK)
+    return;
+
+  for (int i = 0; i < mChanM; i++)
+    floatToShort(tx_buf[i], sendBuffer[i], sendCursor);
+
+  /* Write samples. Fail if we don't get what we want. */
+  int num_smpls = mRadio->writeSamples(tx_buf, mChanM, sendCursor,
+                                       writeTimestamp, &underrun);
+  assert(num_smpls == sendCursor);
+
+  writeTimestamp += (TIMESTAMP) num_smpls;
+  sendCursor = 0;
+}
--- a/Transceiver52M/radioInterface.h
+++ b/Transceiver52M/radioInterface.h
@@ -1,5 +1,5 @@
 /*
-* Copyright 2008 Free Software Foundation, Inc.
+* Copyright 2008, 2012 Free Software Foundation, Inc.
 *
 * This software is distributed under multiple licenses; see the COPYING file in the main directory for licensing information for this specific distribuion.
 *
@@ -12,7 +12,8 @@

 */

-
+#ifndef _RADIOINTEFACE_H_
+#define _RADIOINTEFACE_H_

 #include "sigProcLib.h"  
 #include "GSMCommon.h"
@@ -22,29 +23,31 @@
 #include "radioClock.h"

 /** samples per GSM symbol */
-#define SAMPSPERSYM 1 
+#define SAMPSPERSYM 1
 #define INCHUNK    (625)
 #define OUTCHUNK   (625)
+#define CHAN_MAX    2
+

 static const unsigned gSlotLen = 148;      ///< number of symbols per slot, not counting guard periods

 /** class to interface the transceiver with the USRP */
 class RadioInterface {

-private:
+protected:

-  Thread mAlignRadioServiceLoopThread;	      ///< thread that synchronizes transmit and receive sections
+  int mChanM;                                 ///< channelizer width

-  VectorFIFO  mReceiveFIFO;		      ///< FIFO that holds receive  bursts
+  VectorFIFO mReceiveFIFO[CHAN_MAX];	      ///< FIFO that holds receive  bursts

  RadioDevice *mRadio;			      ///< the USRP object
 
-  float *sendBuffer;
+  float *sendBuffer[CHAN_MAX];
  unsigned sendCursor;

-  float *rcvBuffer;
+  float *rcvBuffer[CHAN_MAX];
  unsigned rcvCursor;
- 
+
  bool underrun;			      ///< indicates writes to USRP are too slow
  bool overrun;				      ///< indicates reads from USRP are too slow
  TIMESTAMP writeTimestamp;		      ///< sample timestamp of next packet written to USRP
@@ -54,8 +57,6 @@ private:

  int samplesPerSymbol;			      ///< samples per GSM symbol
  int receiveOffset;                          ///< offset b/w transmit and receive GSM timestamps, in timeslots
-  int mRadioOversampling;
-  int mTransceiverOversampling;

  bool mOn;				      ///< indicates radio is on

@@ -65,6 +66,10 @@ private:
  int mNumARFCNs;
  signalVector *finalVec, *finalVec9;

+private:
+  /** initialize I/O internals */
+  bool init();
+
  /** format samples to USRP */ 
  int radioifyVector(signalVector &wVector,
                     float *floatVector,
@@ -72,25 +77,34 @@ private:
                     bool zero);

  /** format samples from USRP */
-  int unRadioifyVector(float *floatVector, signalVector &wVector);
+  int unRadioifyVector(float *floatVector, int offset, signalVector &wVector);

  /** push GSM bursts into the transmit buffer */
-  void pushBuffer(void);
+  virtual void pushBuffer(void);

  /** pull GSM bursts from the receive buffer */
-  void pullBuffer(void);
+  virtual void pullBuffer(void);
+
+  /** load receive vectors into FIFO's */
+  void loadVectors(unsigned tN, int samplesPerBurst, int index, GSM::Time rxClock);

 public:

  /** start the interface */
-  void start();
+  bool start();
+  bool stop();
+
+  bool started() { return mOn; };
+
+  /** shutdown interface */
+  void close();

  /** constructor */
-  RadioInterface(RadioDevice* wRadio = NULL,
-		 int receiveOffset = 3,
-		 int wRadioOversampling = SAMPSPERSYM,
-		 int wTransceiverOversampling = SAMPSPERSYM,
-		 GSM::Time wStartTime = GSM::Time(0));
+  RadioInterface(RadioDevice* wRadio,
+		 int wChanM = 1,
+		 int wSPS = SAMPSPERSYM,
+                 int receiveOffset = 3,
+		 GSM::Time wStartTime = GSM::Time(0, 0));
    
  /** destructor */
  ~RadioInterface();
@@ -98,38 +112,32 @@ public:
  void setSamplesPerSymbol(int wSamplesPerSymbol) {if (!mOn) samplesPerSymbol = wSamplesPerSymbol;}

  int getSamplesPerSymbol() { return samplesPerSymbol;}
-
-  /** check for underrun, resets underrun value */
-  bool isUnderrun();
-  
-  /** attach an existing USRP to this interface */
-  void attach(RadioDevice *wRadio, int wRadioOversampling);
-
+ 
  /** return the receive FIFO */
-  VectorFIFO* receiveFIFO() { return &mReceiveFIFO;}
+  VectorFIFO* receiveFIFO(int num) { return &mReceiveFIFO[num];}

  /** return the basestation clock */
  RadioClock* getClock(void) { return &mClock;};

  /** set transmit frequency */
-  bool tuneTx(double freq);
+  bool tuneTx(double freq, int chan = 0);

  /** set receive frequency */
-  bool tuneRx(double freq);
+  bool tuneRx(double freq, int chan = 0);

  /** set receive gain */
-  double setRxGain(double dB);
+  double setRxGain(double dB, int chan = 0);

  /** get receive gain */
-  double getRxGain(void);
+  double getRxGain(int chan = 0);

  /** drive transmission of GSM bursts */
-  void driveTransmitRadio(signalVector &radioBurst, bool zeroBurst);
+  void driveTransmitRadio(signalVector **radioBurst, bool *zeroBurst);

  /** drive reception of GSM bursts */
  void driveReceiveRadio();

-  void setPowerAttenuation(double atten);
+  void setPowerAttenuation(double atten, int chan = 0);

  /** returns the full-scale transmit amplitude **/
  double fullScaleInputValue();
@@ -140,20 +148,8 @@ public:
  /** set thread priority on current thread */
  void setPriority() { mRadio->setPriority(); }

-  /** get transport bus type of attached device */ 
-  enum RadioDevice::busType getBus() { return mRadio->getBus(); }
-
-protected:
-
-  /** drive synchronization of Tx/Rx of USRP */
-  void alignRadio();
-
-  /** reset the interface */
-  void reset();
-
-  friend void *AlignRadioServiceLoopAdapter(RadioInterface*);
-
+  /** get transport window type of attached device */ 
+  enum RadioDevice::TxWindowType getWindowType() { return mRadio->getWindowType(); }
 };

-/** synchronization thread loop */
-void *AlignRadioServiceLoopAdapter(RadioInterface*);
+#endif /* _RADIOINTEFACE_H_ */
--- a/Transceiver52M/radioVector.cpp
+++ b/Transceiver52M/radioVector.cpp
@@ -2,7 +2,7 @@
 * Written by Thomas Tsou <ttsou@vt.edu>
 * Based on code by Harvind S Samra <hssamra@kestrelsp.com>
 *
- * Copyright 2011 Free Software Foundation, Inc.
+ * Copyright 2011, 2012 Free Software Foundation, Inc.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
@@ -41,21 +41,6 @@ bool radioVector::operator>(const radioVector& other) const
 	return mTime > other.mTime;
 }

-unsigned VectorFIFO::size()
-{
-	return mQ.size();
-}
-
-void VectorFIFO::put(radioVector *ptr)
-{
-	mQ.put((void*) ptr);
-}
-
-radioVector *VectorFIFO::get()
-{
-	return (radioVector*) mQ.get();
-}
-
 GSM::Time VectorQueue::nextTime() const
 {
 	GSM::Time retVal;
--- a/Transceiver52M/radioVector.h
+++ b/Transceiver52M/radioVector.h
@@ -2,7 +2,7 @@
 * Written by Thomas Tsou <ttsou@vt.edu>
 * Based on code by Harvind S Samra <hssamra@kestrelsp.com>
 *
- * Copyright 2011 Free Software Foundation, Inc.
+ * Copyright 2011, 2012 Free Software Foundation, Inc.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
@@ -37,14 +37,7 @@ private:
 	GSM::Time mTime;
 };

-class VectorFIFO {
-public:
-	unsigned size();
-	void put(radioVector *ptr);
-	radioVector *get();
-
-private:
-	PointerFIFO mQ;
+class VectorFIFO : public InterthreadQueue<radioVector> {
 };

 class VectorQueue : public InterthreadPriorityQueue<radioVector> {
--- a/Transceiver52M/runTransceiver.cpp
+++ b/Transceiver52M/runTransceiver.cpp
@@ -36,12 +36,6 @@
 #include <Logger.h>
 #include <Configuration.h>

-#ifdef RESAMPLE
-  #define DEVICERATE 400e3
-#else
-  #define DEVICERATE 1625e3/6 
-#endif
-
 using namespace std;

 ConfigurationTable gConfig("/etc/OpenBTS/OpenBTS.db");
@@ -58,6 +52,7 @@ static void ctrlCHandler(int signo)
 int main(int argc, char *argv[])
 {
  std::string deviceArgs;
+  std::string txAntenna, rxAntenna;

  if (argc == 3)
  {
@@ -88,16 +83,43 @@ int main(int argc, char *argv[])

  srandom(time(NULL));

-  int mOversamplingRate = numARFCN/2 + numARFCN;
-  RadioDevice *usrp = RadioDevice::make(DEVICERATE * SAMPSPERSYM);
-  if (!usrp->open(deviceArgs)) {
+  RadioDevice *usrp = RadioDevice::make(SAMPSPERSYM);
+  int radioType = usrp->open(deviceArgs);
+  if (radioType < 0) {
    LOG(ALERT) << "Transceiver exiting..." << std::endl;
    return EXIT_FAILURE;
  }

-  RadioInterface* radio = new RadioInterface(usrp,3,SAMPSPERSYM,mOversamplingRate,false);
-  Transceiver *trx = new Transceiver(gConfig.getNum("TRX.Port"),gConfig.getStr("TRX.IP").c_str(),SAMPSPERSYM,GSM::Time(3,0),radio);
-  trx->receiveFIFO(radio->receiveFIFO());
+  if (gConfig.defines("GSM.Radio.TxAntenna"))
+    txAntenna = gConfig.getStr("GSM.Radio.TxAntenna").c_str();
+  if (gConfig.defines("GSM.Radio.RxAntenna"))
+    rxAntenna = gConfig.getStr("GSM.Radio.RxAntenna").c_str();
+
+  if (txAntenna != "")  
+    usrp->setTxAntenna(txAntenna);
+  if (rxAntenna != "")  
+    usrp->setRxAntenna(rxAntenna);
+
+  LOG(INFO) << "transceiver using transmit antenna " << usrp->getRxAntenna();
+  LOG(INFO) << "transceiver using receive antenna " << usrp->getTxAntenna();
+
+  RadioInterface* radio;
+  switch (radioType) {
+  case RadioDevice::NORMAL:
+    radio = new RadioInterface(usrp, 3, SAMPSPERSYM, false);
+    break;
+  case RadioDevice::RESAMP:
+  default:
+    LOG(ALERT) << "Unsupported configuration";
+    return EXIT_FAILURE;
+  }
+
+  int port = gConfig.getNum("TRX.Port");
+  const char *addr = gConfig.getStr("TRX.IP").c_str();
+  DriveLoop *drive = new DriveLoop(SAMPSPERSYM,GSM::Time(3,0),radio);
+  Transceiver *trx = new Transceiver(port, addr, SAMPSPERSYM, radio, drive, 0);
+  radio->activateChan(0);
+
 /*
  signalVector *gsmPulse = generateGSMPulse(2,1);
  BitVector normalBurstSeg = "0000101010100111110010101010010110101110011000111001101010000";
@@ -130,12 +152,13 @@ int main(int argc, char *argv[])
  usrp->loadBurst(finalVecShort,finalVec.size());
 */
  trx->start();
-  //int i = 0;
+
  while(!gbShutdown) { sleep(1); }//i++; if (i==60) break;}

  cout << "Shutting down transceiver..." << endl;
+  trx->shutdown();

-//  trx->stop();
  delete trx;
-//  delete radio;
+  delete drive;
+  delete radio;
 }
--- a/configure.ac
+++ b/configure.ac
@@ -72,11 +72,6 @@ AC_ARG_WITH(singledb, [
        [enable single daughterboard use on USRP1])
 ])

-AC_ARG_WITH(resamp, [
-    AS_HELP_STRING([--with-resamp],
-        [enable resampling for non-52MHz devices])
-])
-
 AC_ARG_WITH(extref, [
    AS_HELP_STRING([--with-extref],
        [enable external reference on UHD devices])
@@ -98,14 +93,10 @@ AS_IF([test "x$with_usrp1" = "xyes"], [
 ])

 AS_IF([test "x$with_uhd" = "xyes"],[
-    PKG_CHECK_MODULES(UHD, uhd >= 003.002.000)
+    PKG_CHECK_MODULES(UHD, uhd >= 003.004.000)
    AC_DEFINE(USE_UHD, 1, Define to 1 if using UHD)
 ])

-AS_IF([test "x$with_resamp" = "xyes"], [
-    AC_DEFINE(RESAMPLE, 1, Define to 1 for resampling)
-])
-
 AS_IF([test "x$with_extref" = "xyes"], [
    AC_DEFINE(EXTREF, 1, Define to 1 for external reference)
 ])
@@ -114,7 +105,6 @@ AS_IF([test "x$with_singledb" = "xyes"], [
    AC_DEFINE(SINGLEDB, 1, Define to 1 for single daughterboard)
 ])

-AM_CONDITIONAL(RESAMPLE, [test "x$with_resamp" = "xyes"])
 AM_CONDITIONAL(UHD, [test "x$with_uhd" = "xyes"])
 AM_CONDITIONAL(USRP1, [test "x$with_usrp1" = "xyes"])