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https://github.com/RangeNetworks/openbts.git
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c0a5c1509e
git-svn-id: http://wush.net/svn/range/software/public/openbts/trunk@2242 19bc5d8c-e614-43d4-8b26-e1612bc8e597
99 lines
3.0 KiB
C++
99 lines
3.0 KiB
C++
/*
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* Copyright 2009, 2010 Free Software Foundation, Inc.
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*
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* This software is distributed under the terms of the GNU Affero Public License.
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* See the COPYING file in the main directory for details.
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*
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* This use of this software may be subject to additional restrictions.
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* See the LEGAL file in the main directory for details.
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This program is free software: you can redistribute it and/or modify
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it under the terms of the GNU Affero General Public License as published by
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the Free Software Foundation, either version 3 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU Affero General Public License for more details.
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You should have received a copy of the GNU Affero General Public License
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along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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#include <stdlib.h>
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#include <math.h>
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#include <iostream>
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using namespace std;
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int main(int argc, char *argv[])
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{
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if (argc<4) {
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cout << "Hata model path loss calculator." << endl;
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cout << "Inputs: " << endl;
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cout << argv[0] << " <freq MHz> <cableType> <mast A m> <mast B m> <dist m>" << endl;
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cout << "<cableType> is 0 for LNA @ antenna or <x> for LMR-<x>" << endl;
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cout << "Outputs: " << endl;
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cout << "cable loss" << endl;
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cout << "L_u -- urban path+cable loss" << endl;
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cout << "L_su -- suburban path+cable loss" << endl;
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cout << "L_o -- open rural path+cable loss" << endl;
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exit(0);
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}
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// Args: freq, mast ht, dist
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// Output: loss in dB
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float f = atoi(argv[1]);
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int cableType = atoi(argv[2]);
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float h_B = atoi(argv[3]);
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float h_M = atoi(argv[4]);
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float d = atoi(argv[5])/1000.0;
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cout << "f = " << f << " MHz, mast A = " << h_B << " m, mast B = " << h_M << " m, dist = " << d << " km." << endl;
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if (f<200) {
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cout << "sorry, coded for f>200 MHz" << endl;
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exit(0);
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}
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// loss in dB per m per MHz
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float lossCoeff;
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switch (cableType) {
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case 0: lossCoeff = 0.0; break;
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case 195: lossCoeff = 3.8567e-4; break;
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case 400: lossCoeff = 1.35e-4; break;
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case 600: lossCoeff = 8.691e-5; break;
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case 900: lossCoeff = 5.896e-5; break;
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default:
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cerr << "unsupported cable type LMR-" << cableType << endl;
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exit(1);
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}
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// Cable loss
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float cableLoss = lossCoeff * h_B * f;
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cout << "cable loss at mast A is " << cableLoss << " dB" << endl;
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float lh_M = log10(11.75*h_M);
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float C_H = 3.2*lh_M*lh_M-4.97;
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//cout << "C_H = " << C_H << " dB." << endl;
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float logf = log10(f);
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float L_u = 69.55 + 26.16*logf - 13.82*log10(h_B) - C_H + (44.9 - 6.55*log10(h_B))*log10(d);
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L_u += cableLoss;
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cout << "Urban: L_u = " << L_u << " dB." << endl;
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float logf_28 = log10(f/28);
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float L_su = L_u - 2*logf_28*logf_28 - 5.4;
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L_su += cableLoss;
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cout << "Suburban: L_su = " << L_su << " dB." << endl;
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float L_o = L_u - 4.78*logf*logf + 18.33*logf - 40.94;
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L_o += cableLoss;
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cout << "Open: L_o = " << L_o << " dB." << endl;
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}
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