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// This example exports the output constellation to file for debugging.
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <time.h>
#include <getopt.h>
#include <assert.h>
#include "liquid.h"
// flexframesync callback function
static int callback(unsigned char * _header,
int _header_valid,
unsigned char * _payload,
unsigned int _payload_len,
int _payload_valid,
framesyncstats_s _stats,
void * _userdata)
{
const char * filename = (const char*)_userdata;
FILE * fid = fopen(filename,"w");
if (fid == NULL) {
printf("could not open '%s' for writing\n", filename);
return 0;
}
unsigned int i;
for (i=0; i<_stats.num_framesyms; i++)
fprintf(fid,"%12.8f %12.8f\n", crealf(_stats.framesyms[i]), cimagf(_stats.framesyms[i]));
fclose(fid);
return 0;
}
int main(int argc, char *argv[])
{
// options
modulation_scheme ms = LIQUID_MODEM_QPSK; // mod. scheme
crc_scheme check = LIQUID_CRC_32; // data validity check
fec_scheme fec0 = LIQUID_FEC_NONE; // fec (inner)
fec_scheme fec1 = LIQUID_FEC_NONE; // fec (outer)
unsigned int payload_len = 480; // payload length
const char * filename = "flexframesync_debug_example.dat";
// create flexframegen object
flexframegenprops_s fgprops;
flexframegenprops_init_default(&fgprops);
fgprops.mod_scheme = ms;
fgprops.check = check;
fgprops.fec0 = fec0;
fgprops.fec1 = fec1;
flexframegen fg = flexframegen_create(&fgprops);
// create flexframesync object
flexframesync fs = flexframesync_create(callback,(void*)filename);
// assemble the frame (NULL pointers for default values)
flexframegen_assemble(fg, NULL, NULL, payload_len);
// generate the frame in blocks
unsigned int buf_len = 256;
float complex buf[buf_len];
int frame_complete = 0;
while (!frame_complete) {
// write samples to buffer
frame_complete = flexframegen_write_samples(fg, buf, buf_len);
// run through frame synchronizer
flexframesync_execute(fs, buf, buf_len);
}
// destroy allocated objects
flexframegen_destroy(fg);
flexframesync_destroy(fs);
return 0;
}
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