Files
openbts/Transceiver52M/radioInterface.h
Thomas Tsou 9dbadffcc5 Transceiver52M: Replace resampler with SSE enabled implementation
Replace the polyphase filter and resampler with a separate
implementation using SSE enabled convolution. The USRP2 (including
derived devices N200, N210) are the only supported devices that
require sample rate conversion, so set the default resampling
parameters for the 100 MHz FPGA clock. This changes the previous
resampling ratios.

  270.833 kHz -> 400 kHz      (65 / 96)
  270.833 kHz -> 390.625 kHz  (52 / 75)

The new resampling factor uses a USRP resampling factor of 256
instead of 250. On the device, this allows two halfband filters to
be used rather than one. The end result is reduced distortial and
aliasing effecits from CIC filter rolloff.

B100 and USRP1 will no be supported at 400 ksps with these changes.

Signed-off-by: Thomas Tsou <tom@tsou.cc>

git-svn-id: http://wush.net/svn/range/software/public/openbts/trunk@6733 19bc5d8c-e614-43d4-8b26-e1612bc8e597
2013-10-17 06:18:14 +00:00

183 lines
4.7 KiB
C++

/*
* Copyright 2008 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.
*
* This use of this software may be subject to additional restrictions.
* See the LEGAL file in the main directory for details.
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.
*/
#include "sigProcLib.h"
#include "GSMCommon.h"
#include "LinkedLists.h"
#include "radioDevice.h"
#include "radioVector.h"
#include "radioClock.h"
/** samples per GSM symbol */
#define SAMPSPERSYM 1
#define INCHUNK (625)
#define OUTCHUNK (625)
/** class to interface the transceiver with the USRP */
class RadioInterface {
protected:
Thread mAlignRadioServiceLoopThread; ///< thread that synchronizes transmit and receive sections
VectorFIFO mReceiveFIFO; ///< FIFO that holds receive bursts
RadioDevice *mRadio; ///< the USRP object
signalVector *sendBuffer;
signalVector *recvBuffer;
unsigned sendCursor;
unsigned recvCursor;
short *convertRecvBuffer;
short *convertSendBuffer;
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
TIMESTAMP readTimestamp; ///< sample timestamp of next packet read from USRP
RadioClock mClock; ///< the basestation clock!
int sps; ///< samples per GSM symbol
int receiveOffset; ///< offset b/w transmit and receive GSM timestamps, in timeslots
bool mOn; ///< indicates radio is on
double powerScaling;
bool loadTest;
int mNumARFCNs;
signalVector *finalVec, *finalVec9;
private:
/** format samples to USRP */
int radioifyVector(signalVector &wVector,
float *floatVector,
float scale,
bool zero);
/** format samples from USRP */
int unRadioifyVector(float *floatVector, signalVector &wVector);
/** push GSM bursts into the transmit buffer */
virtual void pushBuffer(void);
/** pull GSM bursts from the receive buffer */
virtual void pullBuffer(void);
public:
/** start the interface */
void start();
/** intialization */
virtual bool init();
virtual void close();
/** constructor */
RadioInterface(RadioDevice* wRadio = NULL,
int receiveOffset = 3,
int wSPS = SAMPSPERSYM,
GSM::Time wStartTime = GSM::Time(0));
/** destructor */
virtual ~RadioInterface();
/** 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;}
/** return the basestation clock */
RadioClock* getClock(void) { return &mClock;};
/** set transmit frequency */
bool tuneTx(double freq);
/** set receive frequency */
bool tuneRx(double freq);
/** set receive gain */
double setRxGain(double dB);
/** get receive gain */
double getRxGain(void);
/** drive transmission of GSM bursts */
void driveTransmitRadio(signalVector &radioBurst, bool zeroBurst);
/** drive reception of GSM bursts */
void driveReceiveRadio();
void setPowerAttenuation(double atten);
/** returns the full-scale transmit amplitude **/
double fullScaleInputValue();
/** returns the full-scale receive amplitude **/
double fullScaleOutputValue();
/** set thread priority on current thread */
void setPriority() { mRadio->setPriority(); }
/** get transport window type of attached device */
enum RadioDevice::TxWindowType getWindowType() { return mRadio->getWindowType(); }
#if USRP1
protected:
/** drive synchronization of Tx/Rx of USRP */
void alignRadio();
friend void *AlignRadioServiceLoopAdapter(RadioInterface*);
#endif
};
#if USRP1
/** synchronization thread loop */
void *AlignRadioServiceLoopAdapter(RadioInterface*);
#endif
class RadioInterfaceResamp : public RadioInterface {
private:
signalVector *innerSendBuffer;
signalVector *outerSendBuffer;
signalVector *innerRecvBuffer;
signalVector *outerRecvBuffer;
void pushBuffer();
void pullBuffer();
public:
RadioInterfaceResamp(RadioDevice* wRadio = NULL,
int receiveOffset = 3,
int wSPS = SAMPSPERSYM,
GSM::Time wStartTime = GSM::Time(0));
~RadioInterfaceResamp();
bool init();
void close();
};