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#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <complex.h>
#include <unistd.h>
#include <assert.h>
#include "comp.h"
#include "ofdm_internal.h"
#include "codec2_ofdm.h"
#include "test_bits_ofdm.h" /* payload_data_bits */
#include "mpdecode_core.h"
#define MAX_ERRORS 32
static int ofdm_bitsperframe;
static int ofdm_rowsperframe;
static int ofdm_nuwbits;
static int ofdm_ntxtbits;
static int ofdm_rx_offset;
static int ofdm_data_bitsperframe;
static int ofdm_samplesperframe;
static int ofdm_max_samplesperframe;
static int ofdm_rxbuf;
static int ofdm_m;
static int ofdm_ncp;
// Forwards
void run_modem(struct OFDM *ofdm, int tx_bits[], int rx_bits[], COMP tx_rx[]);
void dummy_code();
/////////////////////////////////////////////////////////////
/// MAIN()
int main(int argc, char *argv[]) {
// Options
int f, i, opt;
int dummy = 0; // flag to use dummy code
int frames = 1; // how many frames
int print = 0; // flag to print all bits
struct OFDM *ofdm;
struct OFDM_CONFIG *ofdm_config;
ofdm = ofdm_create(NULL);
assert(ofdm != NULL);
/* Get a copy of the actual modem config */
ofdm_config = ofdm_get_config_param(ofdm);
ofdm_m = (int) (ofdm_config->fs / ofdm_config->rs);
ofdm_ncp = (int) (ofdm_config->tcp * ofdm_config->fs);
ofdm_bitsperframe = ofdm_get_bits_per_frame(ofdm);
ofdm_rowsperframe = ofdm_bitsperframe / (ofdm_config->nc * ofdm_config->bps);
ofdm_samplesperframe = ofdm_get_samples_per_frame(ofdm);
ofdm_max_samplesperframe = ofdm_get_max_samples_per_frame(ofdm);
ofdm_rxbuf = 3 * ofdm_samplesperframe + 3 * (ofdm_m + ofdm_ncp);
ofdm_nuwbits = (ofdm_config->ns - 1) * ofdm_config->bps - ofdm_config->txtbits;
ofdm_ntxtbits = ofdm_config->txtbits;
ofdm_rx_offset = (ofdm_nuwbits + ofdm_ntxtbits);
ofdm_data_bitsperframe = (ofdm_bitsperframe - ofdm_rx_offset);
int tx_bits[ofdm_data_bitsperframe];
int rx_bits[ofdm_data_bitsperframe];
COMP tx_rx[ofdm_samplesperframe];
while ((opt = getopt(argc, argv, "df:p")) != -1) {
switch (opt) {
case 'd':
dummy = 1;
break;
case 'f':
frames = atoi(optarg);
break;
case 'p':
print = 1;
break;
default:
fprintf(stderr, "Usage: %s [-e] [-f <frames>] [-p]\n", argv[0]);
}
}
for (f = 0; f < frames; f++) {
////////
// Prep inputs
for(i=0; i<ofdm_data_bitsperframe; i++) {
tx_bits[i] = payload_data_bits[(i % (sizeof(payload_data_bits)/sizeof(payload_data_bits[0])))];
}
////////
// Modem (or dummy)
if (dummy) {
dummy_code(tx_bits, rx_bits);
} else {
run_modem(ofdm, tx_bits, rx_bits, tx_rx);
}
////////
// Compare results (or print)
int errors = 0;
if (print) {
for(i=0; i<ofdm_data_bitsperframe; i++) {
fprintf(stderr, "bit %3d: tx = %1d, rx = %1d",
i, tx_bits[i], rx_bits[i + ofdm_rx_offset]);
if (tx_bits[i] != rx_bits[i + ofdm_rx_offset]) {
fprintf(stderr, " Error");
errors ++;
}
fprintf(stderr, "\n");
}
} else {
for(i=0; i<ofdm_data_bitsperframe; i++) {
if (tx_bits[i] != rx_bits[i + ofdm_rx_offset]) {
if (errors < MAX_ERRORS) {
fprintf(stderr, "Error in bit %3d: tx = %1d, rx = %1d\n",
i, tx_bits[i], rx_bits[i + ofdm_rx_offset]);
}
errors++;
}
}
}
fprintf(stderr, "%d Errors\n", errors);
} // for (f<frames
ofdm_destroy(ofdm);
} // end main()
//////////////////////////////////
void run_modem(struct OFDM *ofdm, int tx_bits[], int rx_bits[], COMP tx_rx[]) {
int mod_bits[ofdm_samplesperframe];
int i, j;
///////////
// Mod
///////////
for(i=0; i<ofdm_nuwbits; i++) {
mod_bits[i] = ofdm->tx_uw[i];
}
for(i=ofdm_nuwbits; i<ofdm_nuwbits+ofdm_ntxtbits; i++) {
mod_bits[i] = 0;
}
for(j=0, i=ofdm_nuwbits+ofdm_ntxtbits; j<ofdm_data_bitsperframe; i++,j++) {
mod_bits[i] = tx_bits[j];
}
for(j=0; j<ofdm_data_bitsperframe; i++,j++) {
mod_bits[i] = tx_bits[j];
}
ofdm_mod(ofdm, tx_rx, mod_bits);
///////////
// DeMod
///////////
int Nsam = ofdm_samplesperframe;
int prx = 0;
int nin = ofdm_samplesperframe + 2 * (ofdm_m + ofdm_ncp);
int lnew;
COMP rxbuf_in[ofdm_max_samplesperframe];
for (i=0; i<ofdm_samplesperframe ; i++,prx++) {
ofdm->rxbuf[ofdm_rxbuf-nin+i] = tx_rx[prx].real + tx_rx[prx].imag * I;
}
for (i=ofdm_samplesperframe ; i<nin; i++) {
ofdm->rxbuf[ofdm_rxbuf-nin+i] = 0.0 + 0.0 * I;
}
/* disable estimators for initial testing */
ofdm_set_verbose(ofdm, false);
ofdm_set_timing_enable(ofdm, true);
ofdm_set_foff_est_enable(ofdm, true);
ofdm_set_phase_est_enable(ofdm, true);
ofdm->mean_amp = 1.0;
nin = ofdm_get_nin(ofdm);
/* Insert samples at end of buffer, set to zero if no samples
available to disable phase estimation on future pilots on
last frame of simulation. */
if ((Nsam-prx) < nin) {
lnew = Nsam-prx;
} else {
lnew = nin;
}
for(i=0; i<nin; i++) {
rxbuf_in[i].real = 0.0;
rxbuf_in[i].imag = 0.0;
}
if (lnew) {
for(i=0; i<lnew; i++, prx++) {
rxbuf_in[i] = tx_rx[prx];
}
}
ofdm_demod(ofdm, rx_bits, rxbuf_in);
} // end run_modem()
//////////////////////////////////
void dummy_code(int tx_bits[], int rx_bits[]) {
int i;
for(i=0; i<ofdm_data_bitsperframe; i++) {
rx_bits[i] = tx_bits[i];
}
} // end dummy_code()
/* vi:set ts=4 sts=4 et: */
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