1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
|
/*---------------------------------------------------------------------------*\
FILE........: tfdmdv.c
AUTHOR......: David Rowe
DATE CREATED: April 16 2012
Tests for the C version of the FDMDV modem. This program outputs a
file of Octave vectors that are loaded and automatically tested
against the Octave version of the modem by the Octave script
tfmddv.m
\*---------------------------------------------------------------------------*/
/*
Copyright (C) 2012 David Rowe
All rights reserved.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License version 2.1, as
published by the Free Software Foundation. This program is
distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
License for more details.
You should have received a copy of the GNU Lesser General Public License
along with this program; if not, see <http://www.gnu.org/licenses/>.
*/
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include "fdmdv_internal.h"
#include "codec2_fdmdv.h"
#include "octave.h"
#define FRAMES 35
#define CHANNEL_BUF_SIZE (10*M_FAC)
extern float pilot_coeff[];
int main(int argc, char *argv[])
{
struct FDMDV *fdmdv;
int tx_bits[FDMDV_BITS_PER_FRAME];
COMP tx_symbols[FDMDV_NC+1];
COMP tx_fdm[M_FAC];
float channel[CHANNEL_BUF_SIZE];
int channel_count;
COMP rx_fdm[M_FAC+M_FAC/P];
float foff_coarse;
int nin, next_nin;
COMP rx_fdm_fcorr[M_FAC+M_FAC/P];
COMP rx_fdm_filter[M_FAC+M_FAC/P];
COMP rx_filt[NC+1][P+1];
float rx_timing;
float env[NT*P];
COMP rx_symbols[FDMDV_NC+1];
int rx_bits[FDMDV_BITS_PER_FRAME];
float foff_fine;
int sync_bit, reliable_sync_bit;
int tx_bits_log[FDMDV_BITS_PER_FRAME*FRAMES];
COMP tx_symbols_log[(FDMDV_NC+1)*FRAMES];
COMP tx_fdm_log[M_FAC*FRAMES];
COMP pilot_baseband1_log[NPILOTBASEBAND*FRAMES];
COMP pilot_baseband2_log[NPILOTBASEBAND*FRAMES];
COMP pilot_lpf1_log[NPILOTLPF*FRAMES];
COMP pilot_lpf2_log[NPILOTLPF*FRAMES];
COMP S1_log[MPILOTFFT*FRAMES];
COMP S2_log[MPILOTFFT*FRAMES];
float foff_coarse_log[FRAMES];
float foff_log[FRAMES];
COMP rx_fdm_filter_log[(M_FAC+M_FAC/P)*FRAMES];
int rx_fdm_filter_log_index;
COMP rx_filt_log[NC+1][(P+1)*FRAMES];
int rx_filt_log_col_index;
float env_log[NT*P*FRAMES];
float rx_timing_log[FRAMES];
COMP rx_symbols_log[FDMDV_NC+1][FRAMES];
COMP phase_difference_log[FDMDV_NC+1][FRAMES];
float sig_est_log[FDMDV_NC+1][FRAMES];
float noise_est_log[FDMDV_NC+1][FRAMES];
int rx_bits_log[FDMDV_BITS_PER_FRAME*FRAMES];
float foff_fine_log[FRAMES];
int sync_bit_log[FRAMES];
int sync_log[FRAMES];
int nin_log[FRAMES];
FILE *fout;
int f,c,i,j;
fdmdv = fdmdv_create(FDMDV_NC);
next_nin = M_FAC;
channel_count = 0;
rx_fdm_filter_log_index = 0;
rx_filt_log_col_index = 0;
printf("sizeof FDMDV states: %zd bytes\n", sizeof(struct FDMDV));
for(f=0; f<FRAMES; f++) {
/* --------------------------------------------------------*\
Modulator
\*---------------------------------------------------------*/
fdmdv_get_test_bits(fdmdv, tx_bits);
bits_to_dqpsk_symbols(tx_symbols, FDMDV_NC, fdmdv->prev_tx_symbols, tx_bits, &fdmdv->tx_pilot_bit, 0);
memcpy(fdmdv->prev_tx_symbols, tx_symbols, sizeof(COMP)*(FDMDV_NC+1));
tx_filter_and_upconvert(tx_fdm, FDMDV_NC , tx_symbols, fdmdv->tx_filter_memory,
fdmdv->phase_tx, fdmdv->freq, &fdmdv->fbb_phase_tx, fdmdv->fbb_rect);
/* --------------------------------------------------------*\
Channel
\*---------------------------------------------------------*/
nin = next_nin;
// nin = M_FAC; // when debugging good idea to uncomment this to "open loop"
/* add M_FAC tx samples to end of buffer */
assert((channel_count + M_FAC) < CHANNEL_BUF_SIZE);
for(i=0; i<M_FAC; i++)
channel[channel_count+i] = tx_fdm[i].real;
channel_count += M_FAC;
/* take nin samples from start of buffer */
for(i=0; i<nin; i++) {
rx_fdm[i].real = channel[i];
rx_fdm[i].imag = 0;
}
/* shift buffer back */
for(i=0,j=nin; j<channel_count; i++,j++)
channel[i] = channel[j];
channel_count -= nin;
/* --------------------------------------------------------*\
Demodulator
\*---------------------------------------------------------*/
/* shift down to complex baseband */
fdmdv_freq_shift(rx_fdm, rx_fdm, -FDMDV_FCENTRE, &fdmdv->fbb_phase_rx, nin);
/* freq offset estimation and correction */
// fdmdv->sync = 0; // when debugging good idea to uncomment this to "open loop"
foff_coarse = rx_est_freq_offset(fdmdv, rx_fdm, nin, !fdmdv->sync);
if (fdmdv->sync == 0)
fdmdv->foff = foff_coarse;
fdmdv_freq_shift(rx_fdm_fcorr, rx_fdm, -fdmdv->foff, &fdmdv->foff_phase_rect, nin);
/* baseband processing */
rxdec_filter(rx_fdm_filter, rx_fdm_fcorr, fdmdv->rxdec_lpf_mem, nin);
down_convert_and_rx_filter(rx_filt, fdmdv->Nc, rx_fdm_filter, fdmdv->rx_fdm_mem, fdmdv->phase_rx, fdmdv->freq,
fdmdv->freq_pol, nin, M_FAC/Q);
rx_timing = rx_est_timing(rx_symbols, FDMDV_NC, rx_filt, fdmdv->rx_filter_mem_timing, env, nin, M_FAC);
foff_fine = qpsk_to_bits(rx_bits, &sync_bit, FDMDV_NC, fdmdv->phase_difference, fdmdv->prev_rx_symbols, rx_symbols, 0);
//for(i=0; i<FDMDV_NC;i++)
// printf("rx_symbols: %f %f prev_rx_symbols: %f %f phase_difference: %f %f\n", rx_symbols[i].real, rx_symbols[i].imag,
// fdmdv->prev_rx_symbols[i].real, fdmdv->prev_rx_symbols[i].imag, fdmdv->phase_difference[i].real, fdmdv->phase_difference[i].imag);
//if (f==1)
// exit(0);
snr_update(fdmdv->sig_est, fdmdv->noise_est, FDMDV_NC, fdmdv->phase_difference);
memcpy(fdmdv->prev_rx_symbols, rx_symbols, sizeof(COMP)*(FDMDV_NC+1));
next_nin = M_FAC;
if (rx_timing > 2*M_FAC/P)
next_nin += M_FAC/P;
if (rx_timing < 0)
next_nin -= M_FAC/P;
fdmdv->sync = freq_state(&reliable_sync_bit, sync_bit, &fdmdv->fest_state, &fdmdv->timer, fdmdv->sync_mem);
fdmdv->foff -= TRACK_COEFF*foff_fine;
/* --------------------------------------------------------*\
Log each vector
\*---------------------------------------------------------*/
memcpy(&tx_bits_log[FDMDV_BITS_PER_FRAME*f], tx_bits, sizeof(int)*FDMDV_BITS_PER_FRAME);
memcpy(&tx_symbols_log[(FDMDV_NC+1)*f], tx_symbols, sizeof(COMP)*(FDMDV_NC+1));
memcpy(&tx_fdm_log[M_FAC*f], tx_fdm, sizeof(COMP)*M_FAC);
memcpy(&pilot_baseband1_log[f*NPILOTBASEBAND], fdmdv->pilot_baseband1, sizeof(COMP)*NPILOTBASEBAND);
memcpy(&pilot_baseband2_log[f*NPILOTBASEBAND], fdmdv->pilot_baseband2, sizeof(COMP)*NPILOTBASEBAND);
memcpy(&pilot_lpf1_log[f*NPILOTLPF], fdmdv->pilot_lpf1, sizeof(COMP)*NPILOTLPF);
memcpy(&pilot_lpf2_log[f*NPILOTLPF], fdmdv->pilot_lpf2, sizeof(COMP)*NPILOTLPF);
memcpy(&S1_log[f*MPILOTFFT], fdmdv->S1, sizeof(COMP)*MPILOTFFT);
memcpy(&S2_log[f*MPILOTFFT], fdmdv->S2, sizeof(COMP)*MPILOTFFT);
foff_coarse_log[f] = foff_coarse;
foff_log[f] = fdmdv->foff;
/* rx filtering */
for(i=0; i<nin; i++)
rx_fdm_filter_log[rx_fdm_filter_log_index + i] = rx_fdm_filter[i];
rx_fdm_filter_log_index += nin;
for(c=0; c<NC+1; c++) {
for(i=0; i<(P*nin)/M_FAC; i++)
rx_filt_log[c][rx_filt_log_col_index + i] = rx_filt[c][i];
}
rx_filt_log_col_index += (P*nin)/M_FAC;
/* timing estimation */
memcpy(&env_log[NT*P*f], env, sizeof(float)*NT*P);
rx_timing_log[f] = rx_timing;
nin_log[f] = nin;
for(c=0; c<FDMDV_NC+1; c++) {
rx_symbols_log[c][f] = rx_symbols[c];
phase_difference_log[c][f] = fdmdv->phase_difference[c];
}
/* qpsk_to_bits() */
memcpy(&rx_bits_log[FDMDV_BITS_PER_FRAME*f], rx_bits, sizeof(int)*FDMDV_BITS_PER_FRAME);
for(c=0; c<FDMDV_NC+1; c++) {
sig_est_log[c][f] = fdmdv->sig_est[c];
noise_est_log[c][f] = fdmdv->noise_est[c];
}
foff_fine_log[f] = foff_fine;
sync_bit_log[f] = sync_bit;
sync_log[f] = fdmdv->sync;
}
/*---------------------------------------------------------*\
Dump logs to Octave file for evaluation
by tfdmdv.m Octave script
\*---------------------------------------------------------*/
fout = fopen("tfdmdv_out.txt","wt");
assert(fout != NULL);
fprintf(fout, "# Created by tfdmdv.c\n");
octave_save_int(fout, "tx_bits_log_c", tx_bits_log, 1, FDMDV_BITS_PER_FRAME*FRAMES);
octave_save_complex(fout, "tx_symbols_log_c", tx_symbols_log, 1, (FDMDV_NC+1)*FRAMES, (FDMDV_NC+1)*FRAMES);
octave_save_complex(fout, "tx_fdm_log_c", (COMP*)tx_fdm_log, 1, M_FAC*FRAMES, M_FAC*FRAMES);
octave_save_complex(fout, "pilot_lut_c", (COMP*)fdmdv->pilot_lut, 1, NPILOT_LUT, NPILOT_LUT);
octave_save_complex(fout, "pilot_baseband1_log_c", pilot_baseband1_log, 1, NPILOTBASEBAND*FRAMES, NPILOTBASEBAND*FRAMES);
octave_save_complex(fout, "pilot_baseband2_log_c", pilot_baseband2_log, 1, NPILOTBASEBAND*FRAMES, NPILOTBASEBAND*FRAMES);
octave_save_float(fout, "pilot_coeff_c", pilot_coeff, 1, NPILOTCOEFF, NPILOTCOEFF);
octave_save_complex(fout, "pilot_lpf1_log_c", pilot_lpf1_log, 1, NPILOTLPF*FRAMES, NPILOTLPF*FRAMES);
octave_save_complex(fout, "pilot_lpf2_log_c", pilot_lpf2_log, 1, NPILOTLPF*FRAMES, NPILOTLPF*FRAMES);
octave_save_complex(fout, "S1_log_c", S1_log, 1, MPILOTFFT*FRAMES, MPILOTFFT*FRAMES);
octave_save_complex(fout, "S2_log_c", S2_log, 1, MPILOTFFT*FRAMES, MPILOTFFT*FRAMES);
octave_save_float(fout, "foff_log_c", foff_log, 1, FRAMES, FRAMES);
octave_save_float(fout, "foff_coarse_log_c", foff_coarse_log, 1, FRAMES, FRAMES);
octave_save_complex(fout, "rx_fdm_filter_log_c", (COMP*)rx_fdm_filter_log, 1, rx_fdm_filter_log_index, rx_fdm_filter_log_index);
octave_save_complex(fout, "rx_filt_log_c", (COMP*)rx_filt_log, (FDMDV_NC+1), rx_filt_log_col_index, (P+1)*FRAMES);
octave_save_float(fout, "env_log_c", env_log, 1, NT*P*FRAMES, NT*P*FRAMES);
octave_save_float(fout, "rx_timing_log_c", rx_timing_log, 1, FRAMES, FRAMES);
octave_save_complex(fout, "rx_symbols_log_c", (COMP*)rx_symbols_log, (FDMDV_NC+1), FRAMES, FRAMES);
octave_save_complex(fout, "phase_difference_log_c", (COMP*)phase_difference_log, (FDMDV_NC+1), FRAMES, FRAMES);
octave_save_float(fout, "sig_est_log_c", (float*)sig_est_log, (FDMDV_NC+1), FRAMES, FRAMES);
octave_save_float(fout, "noise_est_log_c", (float*)noise_est_log, (FDMDV_NC+1), FRAMES, FRAMES);
octave_save_int(fout, "rx_bits_log_c", rx_bits_log, 1, FDMDV_BITS_PER_FRAME*FRAMES);
octave_save_float(fout, "foff_fine_log_c", foff_fine_log, 1, FRAMES, FRAMES);
octave_save_int(fout, "sync_bit_log_c", sync_bit_log, 1, FRAMES);
octave_save_int(fout, "sync_log_c", sync_log, 1, FRAMES);
octave_save_int(fout, "nin_log_c", nin_log, 1, FRAMES);
fclose(fout);
fdmdv_destroy(fdmdv);
return 0;
}
|
