forked from ExternalVendorCode/Signal-Server
50 lines
1.1 KiB
C++
50 lines
1.1 KiB
C++
#include <stdio.h>
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#include <stdlib.h>
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#include <math.h>
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double SUIpathLoss(float f, float TxH, float RxH, float d, int mode)
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{
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/*
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f = Frequency (MHz)
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TxH = Transmitter height (m)
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RxH = Receiver height (m)
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d = distance (km)
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mode 1 = Hilly + trees
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mode 2 = Flat + trees OR hilly + light foliage
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mode 3 = Flat + light foliage
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http://www.cl.cam.ac.uk/research/dtg/lce-pub/public/vsa23/VTC05_Empirical.pdf
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*/
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d = d * 1000; // km to m
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if (f < 1900 || f > 11000) {
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printf("Error: SUI model frequency range 1.9-11GHz\n");
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exit(EXIT_FAILURE);
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}
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// Terrain mode A is default
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double a = 4.6;
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double b = 0.0075;
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double c = 12.6;
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double s = 10.6; // Optional fading value
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int XhCF = -10.8;
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if (mode == 2) {
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a = 4.0;
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b = 0.0065;
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c = 17.1;
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s = 6; // average
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}
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if (mode == 3) {
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a = 3.6;
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b = 0.005;
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c = 20;
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s = 3; // Optimistic
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XhCF = -20;
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}
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double d0 = 100;
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double A = 20 * log10((4 * M_PI * d0) / (300 / f));
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double y = (a - b * TxH) + c / TxH;
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double Xf = 6 * log10(f / 2000);
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double Xh = XhCF * log10(RxH / 2);
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return A + (10 * y * log10(d / d0)) + Xf + Xh + s;
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}
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