forked from Guenael/rtlsdr-wsprd
-
Notifications
You must be signed in to change notification settings - Fork 0
/
Copy pathrtlsdr_wsprd.c
1183 lines (1017 loc) · 40 KB
/
rtlsdr_wsprd.c
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
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/*
* rtlsrd-wsprd, WSPR daemon for RTL receivers
* Copyright (C) 2016-2021, Guenael Jouchet (VA2GKA)
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* 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 General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
#include <getopt.h>
#include <math.h>
#include <string.h>
#include <sys/time.h>
#include <pthread.h>
#include <rtl-sdr.h>
#include <curl/curl.h>
#include "./rtlsdr_wsprd.h"
#include "./wsprd/wsprd.h"
#include "./wsprd/wsprsim_utils.h"
/* Sampling definition for RTL devices & WSPR protocol */
#define SIGNAL_LENGHT 120
#define SIGNAL_SAMPLE_RATE 375
#define SAMPLING_RATE 2400000
#define FS4_RATE SAMPLING_RATE / 4
#define DOWNSAMPLING SAMPLING_RATE / SIGNAL_SAMPLE_RATE
#define DEFAULT_BUF_LENGTH (4 * 16384)
#define FIR_TAPS 32
/* Debugging logs */
#define LOG_DEBUG 0
#define LOG_INFO 1
#define LOG_WARN 2
#define LOG_ERROR 3
#define LOG_LEVEL LOG_ERROR
#define LOG(level, ...) if (level >= LOG_LEVEL) fprintf(stderr, __VA_ARGS__)
#define safe_cond_signal(n, m) pthread_mutex_lock(m); pthread_cond_signal(n); pthread_mutex_unlock(m)
#define safe_cond_wait(n, m) pthread_mutex_lock(m); pthread_cond_wait(n, m); pthread_mutex_unlock(m)
/* Thread for decoding */
struct decoder_state {
pthread_t thread;
pthread_attr_t tattr;
pthread_cond_t ready_cond;
pthread_mutex_t ready_mutex;
};
static struct decoder_state decState;
/* Thread for RX (blocking function used) & RTL struct */
static pthread_t dongle;
static rtlsdr_dev_t *rtl_device = NULL;
/* receiver State & Options */
struct receiver_state {
/* Variables used for stop conditions */
bool exit_flag;
/* Double buffering used for sampling */
float iSamples[2][SIGNAL_LENGHT * SIGNAL_SAMPLE_RATE];
float qSamples[2][SIGNAL_LENGHT * SIGNAL_SAMPLE_RATE];
/* Sample index */
uint32_t iqIndex[2];
/* Buffer selected (0 or 1) */
uint32_t bufferIndex;
/* Time at the beginning of the frame to decode */
struct tm *gtm;
};
struct receiver_options {
uint32_t dialfreq;
uint32_t realfreq;
int32_t gain;
int32_t autogain;
int32_t ppm;
int32_t shift;
int32_t upconverter;
int32_t directsampling;
int32_t maxloop;
int32_t nloop;
int32_t device;
bool noreport;
bool selftest;
bool writefile;
bool readfile;
char *filename;
};
/* states & options are shared with other external objects */
struct receiver_state rx_state;
struct receiver_options rx_options;
struct decoder_options dec_options;
struct decoder_results dec_results[50];
/* Could be nice to update this one with the CI */
const char rtlsdr_wsprd_version[] = "0.5.4";
const char wsprnet_app_version[] = "rtlsdr-054"; // 10 chars max.!
/* Callback for each buffer received */
static void rtlsdr_callback(unsigned char *samples, uint32_t samples_count, void *ctx) {
int8_t *sigIn = (int8_t *)samples;
/* CIC buffers/vars */
static int32_t Ix1 = 0, Ix2 = 0,
Qx1 = 0, Qx2 = 0;
static int32_t Iy1 = 0, It1y = 0, It1z = 0,
Qy1 = 0, Qt1y = 0, Qt1z = 0;
static int32_t Iy2 = 0, It2y = 0, It2z = 0,
Qy2 = 0, Qt2y = 0, Qt2z = 0;
static uint32_t decimationIndex = 0;
/* FIR compensation filter coefs
Using : Octave/MATLAB code for generating compensation FIR coefficients
URL : https://github.com/WestCoastDSP/CIC_Octave_Matlab
*/
const static float zCoef[33] = {
-0.0027772683, -0.0005058826, 0.0049745750, -0.0034059318,
-0.0077557814, 0.0139375423, 0.0039896935, -0.0299394142,
0.0162250643, 0.0405130860, -0.0580746013, -0.0272104968,
0.1183705475, -0.0306029022, -0.2011241667, 0.1615898423,
0.5000000000,
0.1615898423, -0.2011241667, -0.0306029022, 0.1183705475,
-0.0272104968, -0.0580746013, 0.0405130860, 0.0162250643,
-0.0299394142, 0.0039896935, 0.0139375423, -0.0077557814,
-0.0034059318, 0.0049745750, -0.0005058826, -0.0027772683
};
/* FIR compensation filter buffers */
static float firI[FIR_TAPS] = {0.0},
firQ[FIR_TAPS] = {0.0};
/* Economic mixer @ fs/4 (upper band)
At fs/4, sin and cosin calculations are no longer required.
0 | pi/2 | pi | 3pi/2
----------------------------
sin = 0 | 1 | 0 | -1 |
cos = 1 | 0 | -1 | 0 |
out_I = in_I * cos(x) - in_Q * sin(x)
out_Q = in_Q * cos(x) + in_I * sin(x)
(Keep the upper band, IQ inverted on RTL devices)
*/
int8_t tmp;
for (uint32_t i = 0; i < samples_count; i += 8) {
sigIn[i ] ^= 0x80; // Unsigned to signed conversion using
sigIn[i+1] ^= 0x80; // XOR as a binary mask to flip the first bit
tmp = (sigIn[i+3] ^ 0x80); // CHECK -127 alt. possible issue ?
sigIn[i+3] = (sigIn[i+2] ^ 0x80);
sigIn[i+2] = -tmp;
sigIn[i+4] = -(sigIn[i+4] ^ 0x80);
sigIn[i+5] = -(sigIn[i+5] ^ 0x80);
tmp = (sigIn[i+6] ^ 0x80);
sigIn[i+6] = (sigIn[i+7] ^ 0x80);
sigIn[i+7] = -tmp;
}
/* CIC decimator (N=2)
Info: * Understanding CIC Compensation Filters
https://www.altera.com/en_US/pdfs/literature/an/an455.pdf
* Understanding cascaded integrator-comb filters
http://www.embedded.com/design/configurable-systems/4006446/Understanding-cascaded-integrator-comb-filters
*/
for (int32_t i = 0; i < samples_count / 2; i++) { // UPDATE: i+=2 & fix below
/* Integrator stages (N=2) */
Ix1 += (int32_t)sigIn[i * 2]; // EVAL: option to move sigIn in float here
Qx1 += (int32_t)sigIn[i * 2 + 1];
Ix2 += Ix1;
Qx2 += Qx1;
/* Decimation stage */
decimationIndex++;
if (decimationIndex <= DOWNSAMPLING) {
continue;
}
decimationIndex = 0;
/* 1st Comb */
Iy1 = Ix2 - It1z;
It1z = It1y;
It1y = Ix2;
Qy1 = Qx2 - Qt1z;
Qt1z = Qt1y;
Qt1y = Qx2;
/* 2nd Comd */
Iy2 = Iy1 - It2z;
It2z = It2y;
It2y = Iy1;
Qy2 = Qy1 - Qt2z;
Qt2z = Qt2y;
Qt2y = Qy1;
/* FIR compensation filter */
float Isum = 0.0,
Qsum = 0.0;
for (uint32_t j = 0; j < FIR_TAPS; j++) {
Isum += firI[j] * zCoef[j];
Qsum += firQ[j] * zCoef[j];
if (j < FIR_TAPS-1) {
firI[j] = firI[j + 1];
firQ[j] = firQ[j + 1];
}
}
firI[FIR_TAPS-1] = (float)Iy2;
firQ[FIR_TAPS-1] = (float)Qy2;
Isum += firI[FIR_TAPS-1] * zCoef[FIR_TAPS];
Qsum += firQ[FIR_TAPS-1] * zCoef[FIR_TAPS];
/* Save the result in the buffer */
uint32_t idx = rx_state.bufferIndex;
if (rx_state.iqIndex[idx] < (SIGNAL_LENGHT * SIGNAL_SAMPLE_RATE)) {
rx_state.iSamples[idx][rx_state.iqIndex[idx]] = Isum;
rx_state.qSamples[idx][rx_state.iqIndex[idx]] = Qsum;
rx_state.iqIndex[idx]++;
}
}
}
static void sigint_callback_handler(int signum) {
fprintf(stderr, "Signal caught %d, exiting!\n", signum);
rx_state.exit_flag = true;
rtlsdr_cancel_async(rtl_device);
}
/* Thread used for this RX blocking function */
static void *rtlsdr_rx(void *arg) {
rtlsdr_read_async(rtl_device, rtlsdr_callback, NULL, 0, DEFAULT_BUF_LENGTH);
rtlsdr_cancel_async(rtl_device);
return NULL;
}
/* Thread used for the decoder */
static void *decoder(void *arg) {
int32_t n_results = 0;
while (!rx_state.exit_flag) {
safe_cond_wait(&decState.ready_cond, &decState.ready_mutex);
LOG(LOG_DEBUG, "Decoder thread -- Got a signal!\n");
if (rx_state.exit_flag)
break; /* Abort case, final sig */
/* Select the previous transmission / other buffer */
uint32_t prevBuffer = (rx_state.bufferIndex + 1) % 2;
if (rx_state.iqIndex[prevBuffer] < ( (SIGNAL_LENGHT - 3) * SIGNAL_SAMPLE_RATE ) ) {
LOG(LOG_DEBUG, "Decoder thread -- Signal too short, skipping!\n");
continue; /* Partial buffer during the first RX, skip it! */
} else {
rx_options.nloop++; /* Decoding this signal, count it! */
}
/* Delete any previous samples tail */
for (int i = rx_state.iqIndex[prevBuffer]; i < SIGNAL_LENGHT * SIGNAL_SAMPLE_RATE; i++) {
rx_state.iSamples[prevBuffer][i] = 0.0;
rx_state.qSamples[prevBuffer][i] = 0.0;
}
/* Normalize the sample @-3dB */
float maxSig = 1e-24f;
for (int i = 0; i < SIGNAL_LENGHT * SIGNAL_SAMPLE_RATE; i++) {
float absI = fabs(rx_state.iSamples[prevBuffer][i]);
float absQ = fabs(rx_state.qSamples[prevBuffer][i]);
if (absI > maxSig)
maxSig = absI;
if (absQ > maxSig)
maxSig = absQ;
}
maxSig = 0.5 / maxSig;
for (int i = 0; i < SIGNAL_LENGHT * SIGNAL_SAMPLE_RATE; i++) {
rx_state.iSamples[prevBuffer][i] *= maxSig;
rx_state.qSamples[prevBuffer][i] *= maxSig;
}
/* Get the date at the beginning last recording session
with 1 second margin added, just to be sure to be on this even minute
*/
time_t unixtime;
time ( &unixtime );
unixtime = unixtime - 120 + 1;
rx_state.gtm = gmtime( &unixtime );
/* Search & decode the signal */
wspr_decode(rx_state.iSamples[prevBuffer],
rx_state.qSamples[prevBuffer],
SIGNAL_LENGHT * SIGNAL_SAMPLE_RATE,
dec_options,
dec_results,
&n_results);
LOG(LOG_DEBUG, "Decoder thread -- Decoding completed\n");
saveSample(rx_state.iSamples[prevBuffer], rx_state.qSamples[prevBuffer]);
postSpots(n_results);
printSpots(n_results);
}
return NULL;
}
/* Double buffer management */
void initSampleStorage() {
rx_state.bufferIndex = 0;
rx_state.iqIndex[0] = 0;
rx_state.iqIndex[1] = 0;
rx_state.exit_flag = false;
}
/* Default options for the receiver */
void initrx_options() {
rx_options.gain = 290;
rx_options.autogain = 0;
rx_options.ppm = 0;
rx_options.shift = 0;
rx_options.directsampling = 0;
rx_options.maxloop = 0;
rx_options.nloop = 0;
rx_options.device = 0;
rx_options.selftest = false;
rx_options.writefile = false;
rx_options.readfile = false;
rx_options.noreport = false;
}
/* Default options for the decoder */
void initDecoder_options() {
dec_options.usehashtable = 0;
dec_options.npasses = 2;
dec_options.subtraction = 1;
dec_options.quickmode = 0;
}
/* Report on WSPRnet */
void postSpots(uint32_t n_results) {
CURL *curl;
CURLcode res;
char url[256];
if (rx_options.noreport) {
LOG(LOG_DEBUG, "Decoder thread -- Skipping the reporting\n");
return;
}
/* No spot to report, stat option used */
// "Table 'wsprnet_db.activity' doesn't exist" reported on web site...
// Anyone has doc about this?
if (n_results == 0) {
snprintf(url, sizeof(url) - 1, "http://wsprnet.org/post?function=wsprstat&rcall=%s&rgrid=%s&rqrg=%.6f&tpct=%.2f&tqrg=%.6f&dbm=%d&version=%s&mode=2",
dec_options.rcall,
dec_options.rloc,
rx_options.dialfreq / 1e6,
0.0f,
rx_options.dialfreq / 1e6,
0,
wsprnet_app_version);
LOG(LOG_DEBUG, "Decoder thread -- Sending empty report using this URL: %s\n", url);
curl = curl_easy_init();
if (curl) {
curl_easy_setopt(curl, CURLOPT_URL, url);
curl_easy_setopt(curl, CURLOPT_NOBODY, 1);
res = curl_easy_perform(curl);
if (res != CURLE_OK)
fprintf(stderr, "curl_easy_perform() failed: %s\n", curl_easy_strerror(res));
curl_easy_cleanup(curl);
}
return;
}
for (uint32_t i = 0; i < n_results; i++) {
snprintf(url, sizeof(url) - 1, "http://wsprnet.org/post?function=wspr&rcall=%s&rgrid=%s&rqrg=%.6f&date=%02d%02d%02d&time=%02d%02d&sig=%.0f&dt=%.1f&tqrg=%.6f&tcall=%s&tgrid=%s&dbm=%s&version=%s&mode=2",
dec_options.rcall,
dec_options.rloc,
dec_results[i].freq,
rx_state.gtm->tm_year - 100,
rx_state.gtm->tm_mon + 1,
rx_state.gtm->tm_mday,
rx_state.gtm->tm_hour,
rx_state.gtm->tm_min,
dec_results[i].snr,
dec_results[i].dt,
dec_results[i].freq,
dec_results[i].call,
dec_results[i].loc,
dec_results[i].pwr,
wsprnet_app_version);
LOG(LOG_DEBUG, "Decoder thread -- Sending spot using this URL: %s\n", url);
curl = curl_easy_init();
if (curl) {
curl_easy_setopt(curl, CURLOPT_URL, url);
curl_easy_setopt(curl, CURLOPT_NOBODY, 1);
res = curl_easy_perform(curl);
if (res != CURLE_OK)
fprintf(stderr, "curl_easy_perform() failed: %s\n", curl_easy_strerror(res));
curl_easy_cleanup(curl);
}
}
}
void printSpots(uint32_t n_results) {
if (n_results == 0) {
return;
}
for (uint32_t i = 0; i < n_results; i++) {
printf("WSPR;%f;%f;%f;%d;%s;%s;%s\n",
dec_results[i].snr,
dec_results[i].dt,
dec_results[i].freq,
(int)dec_results[i].drift,
dec_results[i].call,
dec_results[i].loc,
dec_results[i].pwr);
}
fflush(stdout);
}
void saveSample(float *iSamples, float *qSamples) {
if (rx_options.writefile == true) {
char filename[32];
time_t rawtime;
time(&rawtime);
struct tm *gtm = gmtime(&rawtime);
snprintf(filename, sizeof(filename) - 1, "%.8s_%04d-%02d-%02d_%02d-%02d-%02d.iq",
rx_options.filename,
gtm->tm_year + 1900,
gtm->tm_mon + 1,
gtm->tm_mday,
gtm->tm_hour,
gtm->tm_min,
gtm->tm_sec);
writeRawIQfile(iSamples, qSamples, filename);
}
}
double atofs(char *s) {
/* standard suffixes */
char last;
uint32_t len;
double suff = 1.0;
len = strlen(s);
last = s[len - 1];
s[len - 1] = '\0';
switch (last) {
case 'g':
case 'G':
suff *= 1e3;
case 'm':
case 'M':
suff *= 1e3;
case 'k':
case 'K':
suff *= 1e3;
suff *= atof(s);
s[len - 1] = last;
return suff;
}
s[len - 1] = last;
return atof(s);
}
int32_t parse_u64(char *s, uint64_t *const value) {
uint_fast8_t base = 10;
char *s_end;
uint64_t u64_value;
if (strlen(s) > 2) {
if (s[0] == '0') {
if ((s[1] == 'x') || (s[1] == 'X')) {
base = 16;
s += 2;
} else if ((s[1] == 'b') || (s[1] == 'B')) {
base = 2;
s += 2;
}
}
}
s_end = s;
u64_value = strtoull(s, &s_end, base);
if ((s != s_end) && (*s_end == 0)) {
*value = u64_value;
return 1;
} else {
return 0;
}
}
int32_t readRawIQfile(float *iSamples, float *qSamples, char *filename) {
float filebuffer[2 * SIGNAL_LENGHT * SIGNAL_SAMPLE_RATE];
FILE *fd = fopen(filename, "rb");
if (fd == NULL) {
fprintf(stderr, "Cannot open data file...\n");
return 0;
}
/* Read the IQ file */
int32_t nread = fread(filebuffer, sizeof(float), 2 * SIGNAL_LENGHT * SIGNAL_SAMPLE_RATE, fd);
int32_t recsize = nread / 2;
/* Convert the interleaved buffer into 2 buffers */
for (int32_t i = 0; i < recsize; i++) {
iSamples[i] = filebuffer[2 * i];
qSamples[i] = -filebuffer[2 * i + 1]; // neg, convention used by wsprsim
}
/* Normalize the sample @-3dB */
float maxSig = 1e-24f;
for (int i = 0; i < recsize; i++) {
float absI = fabs(iSamples[i]);
float absQ = fabs(qSamples[i]);
if (absI > maxSig)
maxSig = absI;
if (absQ > maxSig)
maxSig = absQ;
}
maxSig = 0.5 / maxSig;
for (int i = 0; i <recsize; i++) {
iSamples[i] *= maxSig;
qSamples[i] *= maxSig;
}
return recsize;
}
int32_t writeRawIQfile(float *iSamples, float *qSamples, char *filename) {
float filebuffer[2 * SIGNAL_LENGHT * SIGNAL_SAMPLE_RATE];
FILE *fd = fopen(filename, "wb");
if (fd == NULL) {
fprintf(stderr, "Cannot open data file...\n");
return 0;
}
for (int32_t i = 0; i < SIGNAL_LENGHT * SIGNAL_SAMPLE_RATE; i++) {
filebuffer[2 * i] = iSamples[i];
filebuffer[2 * i + 1] = -qSamples[i]; // neg, convention used by wsprsim
}
int32_t nwrite = fwrite(filebuffer, sizeof(float), 2 * SIGNAL_LENGHT * SIGNAL_SAMPLE_RATE, fd);
if (nwrite != 2 * SIGNAL_LENGHT * SIGNAL_SAMPLE_RATE) {
fprintf(stderr, "Cannot write all the data!\n");
return 0;
}
fclose(fd);
return SIGNAL_LENGHT * SIGNAL_SAMPLE_RATE;
}
int32_t readC2file(float *iSamples, float *qSamples, char *filename) {
float filebuffer[2 * SIGNAL_LENGHT * SIGNAL_SAMPLE_RATE];
FILE *fd = fopen(filename, "rb");
int32_t nread;
double frequency;
int type;
char name[15];
if (fd == NULL) {
fprintf(stderr, "Cannot open data file...\n");
return 0;
}
/* Read the header */
nread = fread(name, sizeof(char), 14, fd);
nread = fread(&type, sizeof(int), 1, fd);
nread = fread(&frequency, sizeof(double), 1, fd);
rx_options.dialfreq = frequency;
/* Read the IQ file */
nread = fread(filebuffer, sizeof(float), 2 * SIGNAL_LENGHT * SIGNAL_SAMPLE_RATE, fd);
int32_t recsize = nread / 2;
/* Convert the interleaved buffer into 2 buffers */
for (int32_t i = 0; i < recsize; i++) {
iSamples[i] = filebuffer[2 * i];
qSamples[i] = -filebuffer[2 * i + 1]; // neg, convention used by wsprsim
}
/* Normalize the sample @-3dB */
float maxSig = 1e-24f;
for (int i = 0; i < recsize; i++) {
float absI = fabs(iSamples[i]);
float absQ = fabs(qSamples[i]);
if (absI > maxSig)
maxSig = absI;
if (absQ > maxSig)
maxSig = absQ;
}
maxSig = 0.5 / maxSig;
for (int i = 0; i <recsize; i++) {
iSamples[i] *= maxSig;
qSamples[i] *= maxSig;
}
return recsize;
}
void decodeRecordedFile(char *filename) {
static float iSamples[SIGNAL_LENGHT * SIGNAL_SAMPLE_RATE] = {0};
static float qSamples[SIGNAL_LENGHT * SIGNAL_SAMPLE_RATE] = {0};
static uint32_t samples_len;
int32_t n_results = 0;
if (strcmp(&filename[strlen(filename)-3], ".iq") == 0) {
samples_len = readRawIQfile(iSamples, qSamples, filename);
} else if (strcmp(&filename[strlen(filename)-3], ".c2") == 0) {
samples_len = readC2file(iSamples, qSamples, filename);
} else {
fprintf(stderr, "Not a valid extension!! (only .iq & .c2 files)\n");
return;
}
printf("Number of samples: %d\n", samples_len);
if (samples_len) {
/* Search & decode the signal */
wspr_decode(iSamples, qSamples, samples_len, dec_options, dec_results, &n_results);
printf(" SNR DT Freq Dr Call Loc Pwr\n");
for (uint32_t i = 0; i < n_results; i++) {
printf("Spot : %6.2f %6.2f %10.6f %2d %7s %6s %2s\n",
dec_results[i].snr,
dec_results[i].dt,
dec_results[i].freq,
(int)dec_results[i].drift,
dec_results[i].call,
dec_results[i].loc,
dec_results[i].pwr);
}
}
}
float whiteGaussianNoise(float factor) {
static double V1, V2, U1, U2, S, X;
static int phase = 0;
if (phase == 0) {
do {
U1 = rand() / (double)RAND_MAX;
U2 = rand() / (double)RAND_MAX;
V1 = 2 * U1 - 1;
V2 = 2 * U2 - 1;
S = V1 * V1 + V2 * V2;
} while(S >= 1 || S == 0);
X = V1 * sqrt(-2 * log(S) / S);
} else {
X = V2 * sqrt(-2 * log(S) / S);
}
phase = 1 - phase;
return (float)X * factor;
}
int32_t decoderSelfTest() {
static float iSamples[SIGNAL_LENGHT * SIGNAL_SAMPLE_RATE] = {0};
static float qSamples[SIGNAL_LENGHT * SIGNAL_SAMPLE_RATE] = {0};
static uint32_t samples_len = SIGNAL_LENGHT * SIGNAL_SAMPLE_RATE;
int32_t n_results = 0;
unsigned char symbols[162];
char message[] = "K1JT FN20QI 20";
char hashtab[32768*13] = {0};
char loctab[32768*5] = {0}; // EVAL: code update from wsprd
// Compute sympbols from the message
get_wspr_channel_symbols(message, hashtab, loctab, symbols);
float f0 = 50.0;
float t0 = 2.0; // Caution!! Possible buffer overflow with the index calculation (no user input here!)
float amp = 1.0;
float wgn = 0.02;
double phi = 0.0;
double df = 375.0 / 256.0;
double dt = 1 / 375.0;
// Add signal
for (int i = 0; i < 162; i++) {
double dphi = 2.0 * M_PI * dt * (f0 + ( (double)symbols[i]-1.5) * df);
for (int j = 0; j < 256; j++) {
int index = t0 / dt + 256 * i + j;
iSamples[index] = amp * cos(phi) + whiteGaussianNoise(wgn);
qSamples[index] = amp * sin(phi) + whiteGaussianNoise(wgn);
phi += dphi;
}
}
/* Save the test sample */
writeRawIQfile(iSamples, qSamples, "selftest.iq");
/* Search & decode the signal */
wspr_decode(iSamples, qSamples, samples_len, dec_options, dec_results, &n_results);
printf(" SNR DT Freq Dr Call Loc Pwr\n");
for (uint32_t i = 0; i < n_results; i++) {
printf("Spot(%i) %6.2f %6.2f %10.6f %2d %7s %6s %2s\n",
i,
dec_results[i].snr,
dec_results[i].dt,
dec_results[i].freq,
(int)dec_results[i].drift,
dec_results[i].call,
dec_results[i].loc,
dec_results[i].pwr);
}
/* Simple consistency check */
if (strcmp(dec_results[0].call, "K1JT") &&
strcmp(dec_results[0].loc, "FN20") &&
strcmp(dec_results[0].pwr, "20")) {
return 0;
} else {
return 1;
}
}
void usage(FILE *stream, int32_t status) {
fprintf(stream,
"rtlsdr_wsprd, a simple WSPR daemon for RTL receivers\n\n"
"Use:\trtlsdr_wsprd -f frequency -c callsign -l locator [options]\n"
"\t-f dial frequency [(,k,M) Hz] or band string\n"
"\t If band string is used, the default dial frequency will used.\n"
"\t Bands: LF MF 160m 80m 60m 40m 30m 20m 17m 15m 12m 10m 6m 4m 2m 1m25 70cm 23cm\n"
"\t-c your callsign (12 chars max)\n"
"\t-l your locator grid (6 chars max)\n"
"Receiver extra options:\n"
"\t-g gain [0-49] (default: 29)\n"
"\t-a auto gain (off by default, no parameter)\n"
"\t-o frequency offset (default: 0)\n"
"\t-p crystal correction factor (ppm) (default: 0)\n"
"\t-u upconverter (default: 0, example: 125M)\n"
"\t-d direct sampling [0,1,2] (default: 0, 1 for I input, 2 for Q input)\n"
"\t-n max iterations (default: 0 = infinite loop)\n"
"\t-i device index (in case of multiple receivers, default: 0)\n"
"Decoder extra options:\n"
"\t-H use the hash table (could caught signal 11 on RPi, no parameter)\n"
"\t-Q quick mode, doesn't dig deep for weak signals, no parameter\n"
"\t-S single pass mode, no subtraction (same as original wsprd), no parameter\n"
"\t-x do not report any spots on web clusters (WSPRnet, PSKreporter...)\n"
"Debugging options:\n"
"\t-t decoder self-test (generate a signal & decode), no parameter\n"
"\t-w write received signal and exit [filename prefix]\n"
"\t-r read signal with .iq or .c2 format, decode and exit [filename]\n"
"\t (raw format: 375sps, float 32 bits, 2 channels)\n"
"Other options:\n"
"\t--help show list of options\n"
"\t--version show version of program\n"
"Example:\n"
"\trtlsdr_wsprd -f 2m -c A1XYZ -l AB12cd -g 29 -o -4200\n");
exit(status);
}
int main(int argc, char **argv) {
uint32_t opt;
char *short_options = "f:c:l:g:ao:p:u:d:n:i:tw:r:HQSx";
int32_t option_index = 0;
struct option long_options[] = {
{"help", no_argument, 0, 0 },
{"version", no_argument, 0, 0 },
{0, 0, 0, 0 }
};
int32_t rtl_result;
int32_t rtl_count;
char rtl_vendor[256], rtl_product[256], rtl_serial[256];
initrx_options();
initDecoder_options();
if (argc <= 1)
usage(stdout, EXIT_SUCCESS);
while ((opt = getopt_long(argc, argv, short_options, long_options, &option_index)) != -1) {
switch (opt) {
case 0:
switch (option_index) {
case 0: // --help
usage(stdout, EXIT_SUCCESS);
break;
case 1: // --version
printf("rtlsdr_wsprd v%s\n", rtlsdr_wsprd_version);
exit(EXIT_FAILURE);
break;
}
case 'f': // Frequency
if (!strcasecmp(optarg, "LF")) {
rx_options.dialfreq = 136000;
// Implicit direct sampling for HF bands & lower
if (!rx_options.directsampling)
rx_options.directsampling = 2;
} else if (!strcasecmp(optarg, "MF")) {
rx_options.dialfreq = 474200;
if (!rx_options.directsampling)
rx_options.directsampling = 2;
} else if (!strcasecmp(optarg, "160m")) {
rx_options.dialfreq = 1836600;
if (!rx_options.directsampling)
rx_options.directsampling = 2;
} else if (!strcasecmp(optarg, "80m")) {
rx_options.dialfreq = 3568600;
if (!rx_options.directsampling)
rx_options.directsampling = 2;
} else if (!strcasecmp(optarg, "60m")) {
rx_options.dialfreq = 5287200;
if (!rx_options.directsampling)
rx_options.directsampling = 2;
} else if (!strcasecmp(optarg, "40m")) {
rx_options.dialfreq = 7038600;
if (!rx_options.directsampling)
rx_options.directsampling = 2;
} else if (!strcasecmp(optarg, "30m")) {
rx_options.dialfreq = 10138700;
if (!rx_options.directsampling)
rx_options.directsampling = 2;
} else if (!strcasecmp(optarg, "20m")) {
rx_options.dialfreq = 14095600;
if (!rx_options.directsampling)
rx_options.directsampling = 2;
} else if (!strcasecmp(optarg, "17m")) {
rx_options.dialfreq = 18104600;
if (!rx_options.directsampling)
rx_options.directsampling = 2;
} else if (!strcasecmp(optarg, "15m")) {
rx_options.dialfreq = 21094600;
if (!rx_options.directsampling)
rx_options.directsampling = 2;
} else if (!strcasecmp(optarg, "12m")) {
rx_options.dialfreq = 24924600;
if (!rx_options.directsampling)
rx_options.directsampling = 2;
} else if (!strcasecmp(optarg, "10m")) {
rx_options.dialfreq = 28124600;
if (!rx_options.directsampling)
rx_options.directsampling = 2;
} else if (!strcasecmp(optarg, "6m")) {
rx_options.dialfreq = 50293000;
} else if (!strcasecmp(optarg, "4m")) {
rx_options.dialfreq = 70091000;
} else if (!strcasecmp(optarg, "2m")) {
rx_options.dialfreq = 144489000;
} else if (!strcasecmp(optarg, "1m25")) {
rx_options.dialfreq = 222280000;
} else if (!strcasecmp(optarg, "70cm")) {
rx_options.dialfreq = 432300000;
} else if (!strcasecmp(optarg, "23cm")) {
rx_options.dialfreq = 1296500000;
} else {
rx_options.dialfreq = (uint32_t)atofs(optarg);
}
break;
case 'c': // Callsign
snprintf(dec_options.rcall, sizeof(dec_options.rcall), "%.12s", optarg);
break;
case 'l': // Locator / Grid
snprintf(dec_options.rloc, sizeof(dec_options.rloc), "%.6s", optarg);
break;
case 'g': // Small signal amplifier gain
rx_options.gain = atoi(optarg);
if (rx_options.gain < 0) rx_options.gain = 0;
if (rx_options.gain > 49) rx_options.gain = 49;
rx_options.gain *= 10;
break;
case 'a': // Auto gain
rx_options.autogain = 1;
break;
case 'o': // Fine frequency correction
rx_options.shift = atoi(optarg);
break;
case 'p': // Crystal correction
rx_options.ppm = atoi(optarg);
break;
case 'u': // Upconverter frequency
rx_options.upconverter = (uint32_t)atofs(optarg);
break;
case 'd': // Direct Sampling
rx_options.directsampling = (uint32_t)atofs(optarg);
break;
case 'n': // Stop after n iterations
rx_options.maxloop = (uint32_t)atofs(optarg);
break;
case 'i': // Select the device to use
rx_options.device = (uint32_t)atofs(optarg);
break;
case 'H': // Decoder option, use a hastable
dec_options.usehashtable = 1;
break;
case 'Q': // Decoder option, faster
dec_options.quickmode = 1;
break;
case 'S': // Decoder option, single pass mode (same as original wsprd)
dec_options.subtraction = 0;
dec_options.npasses = 1;
break;
case 'x': // Decoder option, single pass mode (same as original wsprd)
rx_options.noreport = true;
break;
case 't': // Seft test (used in unit-test CI pipeline)
rx_options.selftest = true;
break;
case 'w': // Write a signal and exit
rx_options.writefile = true;
rx_options.filename = optarg;
break;
case 'r': // Read a signal and decode
rx_options.readfile = true;
rx_options.filename = optarg;
break;
default:
usage(stderr, EXIT_FAILURE);
break;
}
}
if (rx_options.dialfreq == 0) {
fprintf(stderr, "Please specify a dial frequency.\n");
fprintf(stderr, " --help for usage...\n");
return EXIT_FAILURE;
}
if (dec_options.rcall[0] == 0) {
fprintf(stderr, "Please specify your callsign.\n");
fprintf(stderr, " --help for usage...\n");
return EXIT_FAILURE;
}
if (dec_options.rloc[0] == 0) {
fprintf(stderr, "Please specify your locator.\n");
fprintf(stderr, " --help for usage...\n");
return EXIT_FAILURE;
}
/* Calcule shift offset */
rx_options.realfreq = rx_options.dialfreq + rx_options.shift + rx_options.upconverter;
/* Store the frequency used for the decoder */
dec_options.freq = rx_options.dialfreq;
if (rx_options.selftest == true) {
if (decoderSelfTest()) {
fprintf(stdout, "Self-test SUCCESS!\n");
return EXIT_SUCCESS;
}
else {
fprintf(stderr, "Self-test FAILED!\n");
return EXIT_FAILURE;
}