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Add support for AM to libmobile and libsdr

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This commit is contained in:
Andreas Eversberg
2019-12-05 17:24:30 +01:00
parent c2f14834e5
commit 150a77b69d
26 changed files with 121 additions and 52 deletions
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92
src/libsdr/sdr.c
View File

@@ -30,6 +30,7 @@ enum paging_signal;
#include <unistd.h>
#include "../libsample/sample.h"
#include "../libfm/fm.h"
#include "../libam/am.h"
#include "../libtimer/timer.h"
#include "../libmobile/sender.h"
#include "sdr_config.h"
@@ -71,8 +72,11 @@ typedef struct sdr_thread {
typedef struct sdr_chan {
double tx_frequency; /* frequency used */
double rx_frequency; /* frequency used */
fm_mod_t mod; /* modulator instance */
fm_demod_t demod; /* demodulator instance */
int am; /* use AM instead of FM */
fm_mod_t fm_mod; /* modulator instance */
fm_demod_t fm_demod; /* demodulator instance */
am_mod_t am_mod; /* modulator instance */
am_demod_t am_demod; /* demodulator instance */
dispmeasparam_t *dmp_rf_level;
dispmeasparam_t *dmp_freq_offset;
dispmeasparam_t *dmp_deviation;
@@ -94,9 +98,10 @@ typedef struct sdr {
wave_rec_t wave_tx_rec;
wave_play_t wave_rx_play;
wave_play_t wave_tx_play;
float *modbuff; /* buffer for FM transmodulation */
float *modbuff; /* buffer for transmodulation */
sample_t *modbuff_I;
sample_t *modbuff_Q;
sample_t *modbuff_carrier;
sample_t *wavespl0; /* sample buffer for wave generation */
sample_t *wavespl1;
} sdr_t;
@@ -131,7 +136,7 @@ static void show_spectrum(const char *direction, double halfbandwidth, double ce
PDEBUG(DSDR, DEBUG_INFO, "Frequency P = %.4f MHz (Paging Frequency)\n", paging_frequency / 1e6);
}
void *sdr_open(const char __attribute__((__unused__)) *audiodev, double *tx_frequency, double *rx_frequency, int channels, double paging_frequency, int samplerate, int latspl, double max_deviation, double max_modulation)
void *sdr_open(const char __attribute__((__unused__)) *audiodev, double *tx_frequency, double *rx_frequency, int *am, int channels, double paging_frequency, int samplerate, int latspl, double max_deviation, double max_modulation, double modulation_index)
{
sdr_t *sdr;
int threads = 1, oversample = 1; /* always use threads */
@@ -231,6 +236,11 @@ void *sdr_open(const char __attribute__((__unused__)) *audiodev, double *tx_freq
PDEBUG(DSDR, DEBUG_ERROR, "NO MEM!\n");
goto error;
}
sdr->modbuff_carrier = calloc(sdr->latspl, sizeof(*sdr->modbuff_carrier));
if (!sdr->modbuff_carrier) {
PDEBUG(DSDR, DEBUG_ERROR, "NO MEM!\n");
goto error;
}
sdr->wavespl0 = calloc(sdr->latspl, sizeof(*sdr->wavespl0));
if (!sdr->wavespl0) {
PDEBUG(DSDR, DEBUG_ERROR, "NO MEM!\n");
@@ -297,7 +307,14 @@ void *sdr_open(const char __attribute__((__unused__)) *audiodev, double *tx_freq
double tx_offset;
tx_offset = sdr->chan[c].tx_frequency - tx_center_frequency;
PDEBUG(DSDR, DEBUG_DEBUG, "Frequency #%d: TX offset: %.6f MHz\n", c, tx_offset / 1e6);
rc = fm_mod_init(&sdr->chan[c].mod, samplerate, tx_offset, sdr->amplitude);
sdr->chan[c].am = am[c];
if (am[c]) {
double gain, bias;
gain = modulation_index / 2.0;
bias = 1.0 - gain;
rc = am_mod_init(&sdr->chan[c].am_mod, samplerate, tx_offset, sdr->amplitude * gain, sdr->amplitude * bias);
} else
rc = fm_mod_init(&sdr->chan[c].fm_mod, samplerate, tx_offset, sdr->amplitude);
if (rc < 0)
goto error;
}
@@ -305,7 +322,7 @@ void *sdr_open(const char __attribute__((__unused__)) *audiodev, double *tx_freq
double tx_offset;
tx_offset = sdr->chan[sdr->paging_channel].tx_frequency - tx_center_frequency;
PDEBUG(DSDR, DEBUG_DEBUG, "Paging Frequency: TX offset: %.6f MHz\n", tx_offset / 1e6);
rc = fm_mod_init(&sdr->chan[sdr->paging_channel].mod, samplerate, tx_offset, sdr->amplitude);
rc = fm_mod_init(&sdr->chan[sdr->paging_channel].fm_mod, samplerate, tx_offset, sdr->amplitude);
if (rc < 0)
goto error;
}
@@ -400,7 +417,11 @@ void *sdr_open(const char __attribute__((__unused__)) *audiodev, double *tx_freq
double rx_offset;
rx_offset = sdr->chan[c].rx_frequency - rx_center_frequency;
PDEBUG(DSDR, DEBUG_DEBUG, "Frequency #%d: RX offset: %.6f MHz\n", c, rx_offset / 1e6);
rc = fm_demod_init(&sdr->chan[c].demod, samplerate, rx_offset, bandwidth);
sdr->chan[c].am = am[c];
if (am[c])
rc = am_demod_init(&sdr->chan[c].am_demod, samplerate, rx_offset, bandwidth, 1.0 / modulation_index);
else
rc = fm_demod_init(&sdr->chan[c].fm_demod, samplerate, rx_offset, bandwidth / 2.0);
if (rc < 0)
goto error;
}
@@ -428,8 +449,10 @@ void *sdr_open(const char __attribute__((__unused__)) *audiodev, double *tx_freq
if (!sender)
continue;
sdr->chan[c].dmp_rf_level = display_measurements_add(&sender->dispmeas, "RF Level", "%.1f dB", DISPLAY_MEAS_AVG, DISPLAY_MEAS_LEFT, -96.0, 0.0, -INFINITY);
sdr->chan[c].dmp_freq_offset = display_measurements_add(&sender->dispmeas, "Freq. Offset", "%+.2f KHz", DISPLAY_MEAS_AVG, DISPLAY_MEAS_CENTER, -max_deviation / 1000.0 * 2.0, max_deviation / 1000.0 * 2.0, 0.0);
sdr->chan[c].dmp_deviation = display_measurements_add(&sender->dispmeas, "Deviation", "%.2f KHz", DISPLAY_MEAS_PEAK2PEAK, DISPLAY_MEAS_LEFT, 0.0, max_deviation / 1000.0 * 1.5, max_deviation / 1000.0);
if (!am[c]) {
sdr->chan[c].dmp_freq_offset = display_measurements_add(&sender->dispmeas, "Freq. Offset", "%+.2f KHz", DISPLAY_MEAS_AVG, DISPLAY_MEAS_CENTER, -max_modulation / 1000.0 * 2.0, max_modulation / 1000.0 * 2.0, 0.0);
sdr->chan[c].dmp_deviation = display_measurements_add(&sender->dispmeas, "Deviation", "%.2f KHz", DISPLAY_MEAS_PEAK2PEAK, DISPLAY_MEAS_LEFT, 0.0, max_deviation / 1000.0 * 1.5, max_deviation / 1000.0);
}
}
}
@@ -700,6 +723,7 @@ void sdr_close(void *inst)
free(sdr->modbuff);
free(sdr->modbuff_I);
free(sdr->modbuff_Q);
free(sdr->modbuff_carrier);
free(sdr->wavespl0);
free(sdr->wavespl1);
wave_destroy_record(&sdr->wave_rx_rec);
@@ -710,11 +734,13 @@ void sdr_close(void *inst)
int c;
for (c = 0; c < sdr->channels; c++) {
fm_mod_exit(&sdr->chan[c].mod);
fm_demod_exit(&sdr->chan[c].demod);
fm_mod_exit(&sdr->chan[c].fm_mod);
fm_demod_exit(&sdr->chan[c].fm_demod);
am_mod_exit(&sdr->chan[c].am_mod);
am_demod_exit(&sdr->chan[c].am_demod);
}
if (sdr->paging_channel)
fm_mod_exit(&sdr->chan[sdr->paging_channel].mod);
fm_mod_exit(&sdr->chan[sdr->paging_channel].fm_mod);
free(sdr->chan);
}
free(sdr);
@@ -747,9 +773,12 @@ int sdr_write(void *inst, sample_t **samples, uint8_t **power, int num, enum pag
for (c = 0; c < channels; c++) {
/* switch to paging channel, if requested */
if (on[c] && sdr->paging_channel)
fm_modulate_complex(&sdr->chan[sdr->paging_channel].mod, samples[c], power[c], num, buff);
else
fm_modulate_complex(&sdr->chan[c].mod, samples[c], power[c], num, buff);
fm_modulate_complex(&sdr->chan[sdr->paging_channel].fm_mod, samples[c], power[c], num, buff);
else if (sdr->chan[c].am) {
if (power[c][0])
am_modulate_complex(&sdr->chan[c].am_mod, samples[c], num, buff);
} else
fm_modulate_complex(&sdr->chan[c].fm_mod, samples[c], power[c], num, buff);
}
} else {
buff = (float *)samples;
@@ -914,7 +943,10 @@ int sdr_read(void *inst, sample_t **samples, int num, int channels, double *rf_l
if (channels) {
for (c = 0; c < channels; c++) {
fm_demodulate_complex(&sdr->chan[c].demod, samples[c], count, buff, sdr->modbuff_I, sdr->modbuff_Q);
if (sdr->chan[c].am)
am_demodulate_complex(&sdr->chan[c].am_demod, samples[c], count, buff, sdr->modbuff_I, sdr->modbuff_Q, sdr->modbuff_carrier);
else
fm_demodulate_complex(&sdr->chan[c].fm_demod, samples[c], count, buff, sdr->modbuff_I, sdr->modbuff_Q);
sender_t *sender = get_sender_by_empfangsfrequenz(sdr->chan[c].rx_frequency);
if (!sender || !count)
continue;
@@ -928,20 +960,22 @@ int sdr_read(void *inst, sample_t **samples, int num, int channels, double *rf_l
avg = log10(avg) * 20;
display_measurements_update(sdr->chan[c].dmp_rf_level, avg, 0.0);
rf_level_db[c] = avg;
min = 0.0;
max = 0.0;
avg = 0.0;
for (s = 0; s < count; s++) {
avg += samples[c][s];
if (s == 0 || samples[c][s] > max)
max = samples[c][s];
if (s == 0 || samples[c][s] < min)
min = samples[c][s];
if (!sdr->chan[c].am) {
min = 0.0;
max = 0.0;
avg = 0.0;
for (s = 0; s < count; s++) {
avg += samples[c][s];
if (s == 0 || samples[c][s] > max)
max = samples[c][s];
if (s == 0 || samples[c][s] < min)
min = samples[c][s];
}
avg /= (double)count;
display_measurements_update(sdr->chan[c].dmp_freq_offset, avg / 1000.0, 0.0);
/* use half min and max, because we want the deviation above/below (+-) center frequency. */
display_measurements_update(sdr->chan[c].dmp_deviation, min / 2.0 / 1000.0, max / 2.0 / 1000.0);
}
avg /= (double)count;
display_measurements_update(sdr->chan[c].dmp_freq_offset, avg / 1000.0, 0.0);
/* use half min and max, because we want the deviation above/below (+-) center frequency. */
display_measurements_update(sdr->chan[c].dmp_deviation, min / 2.0 / 1000.0, max / 2.0 / 1000.0);
}
}

2
src/libsdr/sdr.h
View File

@@ -2,7 +2,7 @@
enum paging_signal;
int sdr_start(void *inst);
void *sdr_open(const char *audiodev, double *tx_frequency, double *rx_frequency, int channels, double paging_frequency, int samplerate, int latspl, double max_deviation, double max_modulation);
void *sdr_open(const char *audiodev, double *tx_frequency, double *rx_frequency, int *am, int channels, double paging_frequency, int samplerate, int latspl, double max_deviation, double max_modulation, double modulation_index);
void sdr_close(void *inst);
int sdr_write(void *inst, sample_t **samples, uint8_t **power, int num, enum paging_signal *paging_signal, int *on, int channels);
int sdr_read(void *inst, sample_t **samples, int num, int channels, double *rf_level_db);