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rtl_power: nicer errors, low pass, low bw

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Signed-off-by: Steve Markgraf <steve@steve-m.de>
master
Kyle Keen 11 years ago committed by Steve Markgraf
parent 968b6fbfdc
commit 8f1d108122
1 changed files with 85 additions and 39 deletions
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  1. 124
      src/rtl_power.c

124
src/rtl_power.c
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@ -34,7 +34,7 @@
* general astronomy usefulness
* multiple dongles
* multiple FFT workers
* bandwidths smaller than 1MHz
* bandwidths smaller than 1MHz (with optional xlate?)
* check edge cropping for off-by-one and rounding errors
* 1.8MS/s for hiding xtal harmonics
*/
@ -87,6 +87,8 @@ struct tuning_state
int bin_e;
long *avg; /* length == 2^bin_e */
int samples;
int downsample;
double crop;
//pthread_rwlock_t avg_lock;
//pthread_mutex_t avg_mutex;
/* having the iq buffer here is wasteful, but will avoid contention */
@ -127,7 +129,7 @@ void usage(void)
// kaiser
"\t[-c crop_percent (default: 0%, recommended: 20%%-50%%)]\n"
"\t (discards data at the edges, 100%% discards everything)\n"
"\t (has no effect in rms bin mode)\n"
"\t (has no effect for bins > 1MHz or bandwidth < 1MHz)\n"
"\n"
"CSV FFT output columns:\n"
"\tdate, time, Hz low, Hz high, Hz step, samples, dbm, dbm, ...\n\n"
@ -146,6 +148,18 @@ void usage(void)
exit(1);
}
void multi_bail(void)
{
if (do_exit == 1)
{
fprintf(stderr, "Signal caught, finishing scan pass.\n");
}
if (do_exit >= 2)
{
fprintf(stderr, "Signal caught, aborting immediately.\n");
}
}
#ifdef _WIN32
BOOL WINAPI
sighandler(int signum)
@ -165,18 +179,6 @@ static void sighandler(int signum)
}
#endif
void multi_bail(void)
{
if (do_exit == 1)
{
fprintf(stderr, "Signal caught, finishing scan pass.\n");
}
if (do_exit >= 2)
{
fprintf(stderr, "Signal caught, aborting immediately.\n");
}
}
/* more cond dumbness */
#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)
@ -475,7 +477,8 @@ void frequency_range(char *arg, double crop)
// do we want the fewest ranges (easy) or the fewest bins (harder)?
{
char *start, *stop, *step;
int i, j, upper, lower, max_size, bw_seen, bw_used, bin_size, bin_e, buf_len;
int i, j, upper, lower, max_size, bw_seen, bw_used, bin_e, buf_len, downsample;
double bin_size;
struct tuning_state *ts;
/* hacky string parsing */
start = arg;
@ -488,20 +491,27 @@ void frequency_range(char *arg, double crop)
max_size = (int)atofs(step);
stop[-1] = ':';
step[-1] = ':';
downsample = 1;
if ((upper - lower) < 1000000) {
crop = 0.0;}
/* evenly sized ranges, as close to 2MHz as possible */
for (i=1; i<1500; i++) {
bw_seen = (upper - lower) / i;
bw_used = (int)((double)(bw_seen) / (1.0 - crop));
if (bw_used > 2000000) {
continue;}
if (bw_used < 1000000) {
downsample = 2000000 / bw_seen;
bw_used = bw_seen * downsample;
}
tune_count = i;
break;
}
/* number of bins is power-of-two, bin size is under limit */
for (i=1; i<=21; i++) {
bin_e = i;
bin_size = bw_used / (1<<i);
if (bin_size <= max_size) {
bin_size = (double)bw_used / (double)((1<<i) * downsample);
if (bin_size <= (double)max_size) {
break;}
}
/* unless giant bins */
@ -510,14 +520,15 @@ void frequency_range(char *arg, double crop)
bw_used = max_size;
tune_count = (upper - lower) / bw_seen;
bin_e = 0;
crop = 0;
}
if (tune_count > MAX_TUNES) {
fprintf(stderr, "Error: bandwidth too wide.\n");
exit(1);
}
buf_len = DEFAULT_BUF_LENGTH;
if ((2<<bin_e) > buf_len) {
buf_len = (2<<bin_e);
buf_len = (1<<bin_e) * 2 * downsample;
if (buf_len < DEFAULT_BUF_LENGTH) {
buf_len = DEFAULT_BUF_LENGTH;
}
/* build the array */
for (i=0; i<tune_count; i++) {
@ -526,6 +537,8 @@ void frequency_range(char *arg, double crop)
ts->rate = bw_used;
ts->bin_e = bin_e;
ts->samples = 0;
ts->crop = crop;
ts->downsample = downsample;
ts->avg = (long*)malloc((1<<bin_e) * sizeof(long));
if (!ts->avg) {
fprintf(stderr, "Error: malloc.\n");
@ -544,11 +557,13 @@ void frequency_range(char *arg, double crop)
/* report */
fprintf(stderr, "Number of frequency hops: %i\n", tune_count);
fprintf(stderr, "Dongle bandwidth: %iHz\n", bw_used);
fprintf(stderr, "Downsampling by: %ix\n", downsample);
fprintf(stderr, "Cropping by: %0.2f%%\n", crop*100);
fprintf(stderr, "Total FFT bins: %i\n", tune_count * (1<<bin_e));
fprintf(stderr, "Logged FFT bins: %i\n", \
(int)((double)(tune_count * (1<<bin_e)) * (1.0-crop)));
fprintf(stderr, "FFT bin size: %iHz\n", bin_size);
fprintf(stderr, "Buffer size: %0.2fms\n", 1000 * 0.5 * (float)buf_len / (float)bw_used);
fprintf(stderr, "FFT bin size: %0.2fHz\n", bin_size);
fprintf(stderr, "Buffer size: %i bytes (%0.2fms)\n", buf_len, 1000 * 0.5 * (float)buf_len / (float)bw_used);
}
void retune(rtlsdr_dev_t *d, int freq)
@ -565,7 +580,8 @@ void retune(rtlsdr_dev_t *d, int freq)
void scanner(void)
{
int i, j, f, n_read, offset, bin_e, bin_len, buf_len;
int i, j, j2, f, n_read, offset, bin_e, bin_len, buf_len, ds;
int32_t w;
struct tuning_state *ts;
bin_e = tunes[0].bin_e;
bin_len = 1 << bin_e;
@ -585,31 +601,48 @@ void scanner(void)
rms_power(ts);
continue;
}
/* fft */
/* sign and downsample */
for (j=0; j<buf_len; j++) {
fft_buf[j] = (int16_t)ts->buf8[j] - 127;
fft_buf[j] = 0;
}
for (offset=0; offset<buf_len; offset+=(2*bin_len)) {
ds = ts->downsample;
j=0, j2=0;
while (j < buf_len) {
fft_buf[j2] += (int16_t)ts->buf8[j] - 127;
fft_buf[j2+1] += (int16_t)ts->buf8[j+1] - 127;
j += 2;
if (j % (ds*2) == 0) {
j2 += 2;}
}
/* fft */
for (offset=0; offset<(buf_len/ds); offset+=(2*bin_len)) {
// todo, let rect skip this
for (j=0; j<bin_len; j++) {
fft_buf[offset+j*2] *= window_coefs[j];
fft_buf[offset+j*2+1] *= window_coefs[j];
w = (int32_t)fft_buf[offset+j*2];
w *= (int32_t)(window_coefs[j]);
//w /= (int32_t)(ds);
fft_buf[offset+j*2] = (int16_t)w;
w = (int32_t)fft_buf[offset+j*2+1];
w *= (int32_t)(window_coefs[j]);
//w /= (int32_t)(ds);
fft_buf[offset+j*2+1] = (int16_t)w;
}
fix_fft(fft_buf+offset, bin_e);
for (j=0; j<bin_len; j++) {
ts->avg[j] += (long) abs(fft_buf[offset+j*2]);
}
ts->samples += 1;
ts->samples += ds;
}
}
}
void csv_dbm(struct tuning_state *ts, double crop)
void csv_dbm(struct tuning_state *ts)
{
int i, len, i1, i2, bw2, bin_count;
int i, len, ds, i1, i2, bw2, bin_count;
long tmp;
double dbm;
len = 1 << ts->bin_e;
ds = ts->downsample;
/* fix FFT stuff quirks */
if (ts->bin_e > 0) {
/* nuke DC component (not effective for all windows) */
@ -622,14 +655,14 @@ void csv_dbm(struct tuning_state *ts, double crop)
}
}
/* Hz low, Hz high, Hz step, samples, dbm, dbm, ... */
bin_count = (int)((double)len * (1.0 - crop));
bw2 = (int)(((double)ts->rate * (double)bin_count) / (len * 2));
bin_count = (int)((double)len * (1.0 - ts->crop));
bw2 = (int)(((double)ts->rate * (double)bin_count) / (len * 2 * ds));
fprintf(file, "%i, %i, %.2f, %i, ", ts->freq - bw2, ts->freq + bw2,
(double)ts->rate / (double)len, ts->samples);
(double)ts->rate / (double)(len*ds), ts->samples);
// something seems off with the dbm math
i1 = 0 + (int)((double)len * crop * 0.5);
i2 = (len-1) - (int)((double)len * crop * 0.5);
for (i=i1; i<i2; i++) {
i1 = 0 + (int)((double)len * ts->crop * 0.5);
i2 = (len-1) - (int)((double)len * ts->crop * 0.5);
for (i=i1; i<=i2; i++) {
dbm = (double)ts->avg[i];
dbm /= (double)ts->rate;
dbm /= (double)ts->samples;
@ -655,6 +688,7 @@ int main(int argc, char **argv)
#endif
char *filename = NULL;
int i, length, n_read, r, opt, wb_mode = 0;
int f_set = 0;
int gain = AUTO_GAIN; // tenths of a dB
uint8_t *buffer;
uint32_t dev_index = 0;
@ -678,6 +712,7 @@ int main(int argc, char **argv)
switch (opt) {
case 'f': // lower:upper:bin_size
freq_optarg = strdup(optarg);
f_set = 1;
break;
case 'd':
dev_index = atoi(optarg);
@ -734,6 +769,16 @@ int main(int argc, char **argv)
}
}
if (!f_set) {
fprintf(stderr, "No frequency range provided.\n");
exit(1);
}
if ((crop < 0.0) || (crop > 1.0)) {
fprintf(stderr, "Crop value outside of 0 to 1.\n");
exit(1);
}
frequency_range(freq_optarg, crop);
if (tune_count == 0) {
@ -803,6 +848,7 @@ int main(int argc, char **argv)
if (strcmp(filename, "-") == 0) { /* Write log to stdout */
file = stdout;
#ifdef _WIN32
// Is this necessary? Output is ascii.
_setmode(_fileno(file), _O_BINARY);
#endif
} else {
@ -833,14 +879,14 @@ int main(int argc, char **argv)
while (!do_exit) {
scanner();
time_now = time(NULL);
if (time_now <= next_tick) {
if (time_now < next_tick) {
continue;}
// time, Hz low, Hz high, Hz step, samples, dbm, dbm, ...
cal_time = localtime(&time_now);
strftime(t_str, 50, "%Y-%m-%d, %H:%M:%S", cal_time);
for (i=0; i<tune_count; i++) {
fprintf(file, "%s, ", t_str);
csv_dbm(&tunes[i], crop);
csv_dbm(&tunes[i]);
}
fflush(file);
while (time(NULL) >= next_tick) {

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