mirror
/
rtl-wmbus
kopia lustrzana https://github.com/xaelsouth/rtl-wmbus
1
0
Forkuj 0
Kod Zgłoszenia Projekty Wydania Wiki Aktywność

droppped one freq shift

pull/18/head
Xael South 2021-02-05 21:48:05 +00:00
rodzic 284dd6cc0e
commit 9ab45b4866
2 zmienionych plików z 34 dodań i 35 usunięć
Pokaż statystyki Ściągnij plik aktualizacji Ściągnij plik porównania Expand all files Collapse all files

65
rtl_wmbus.c
Wyświetl plik

@ -135,7 +135,7 @@ static inline float moving_average_s1(float sample, size_t i_or_q)
return mavgi(sample, &filter[i_or_q]);
}
static inline float lp_fir_butter_1600kHz_160kHz_200kHz(float sample, size_t i_or_q)
static inline float lp_fir_butter_1600kHz_160kHz_200kHz_t1_c1(float sample, size_t i_or_q)
{
#define COEFFS 23
static const float b[COEFFS] = {0.000140535927, 1.102280392e-05, 0.0001309279731, 0.001356012537, 0.00551787474, 0.01499414005, 0.03160167988, 0.05525973093, 0.08315031015, 0.1099887688, 0.1295143636, 0.1366692652, 0.1295143636, 0.1099887688, 0.08315031015, 0.05525973093, 0.03160167988, 0.01499414005, 0.00551787474, 0.001356012537, 0.0001309279731, 1.102280392e-05, 0.000140535927, };
@ -154,6 +154,24 @@ static inline float lp_fir_butter_1600kHz_160kHz_200kHz(float sample, size_t i_o
return firf(sample, &filter[i_or_q]);
}
static inline float lp_fir_butter_1600kHz_160kHz_200kHz_s1(float sample, size_t i_or_q)
{
#define COEFFS 23
static const float b[COEFFS] = {0.000140535927, 1.102280392e-05, 0.0001309279731, 0.001356012537, 0.00551787474, 0.01499414005, 0.03160167988, 0.05525973093, 0.08315031015, 0.1099887688, 0.1295143636, 0.1366692652, 0.1295143636, 0.1099887688, 0.08315031015, 0.05525973093, 0.03160167988, 0.01499414005, 0.00551787474, 0.001356012537, 0.0001309279731, 1.102280392e-05, 0.000140535927, };
//static const float b[COEFFS] = {0.001645672124, 0.0004733757463, -0.002542116469, -0.008572441674, -0.01545406295, -0.01651661113, -0.002914917097, 0.03113207374, 0.08317149659, 0.1410058012, 0.1866042197, 0.2039350204, 0.1866042197, 0.1410058012, 0.08317149659, 0.03113207374, -0.002914917097, -0.01651661113, -0.01545406295, -0.008572441674, -0.002542116469, 0.0004733757463, 0.001645672124, };
static float i_hist[COEFFS] = {};
static float q_hist[COEFFS] = {};
static FIRF_FILTER filter[2] = // i/q
{
{.length = COEFFS, .b = b, .hist = i_hist}, // 0
{.length = COEFFS, .b = b, .hist = q_hist} // 1
};
#undef COEFFS
return firf(sample, &filter[i_or_q]);
}
static inline float lp_firfp_butter_1600kHz_160kHz_200kHz(float sample, size_t i_or_q)
{
@ -638,10 +656,10 @@ void setup_lookup_tables_for_frequency_translation(int fs_kHz)
}
}
/* Positive frequencies shift: ft = 50kHz the signal will shift from 868.9M right to 868.95M. */
static void shift_freq_50(float *i, float *q, int fs_kHz)
/* Positive frequencies shift: ft = 250kHz the signal will shift from 868.7M right to 868.95M. */
static void shift_freq_250(float *i, float *q, int fs_kHz)
{
const int ft = 50;
const int ft = 250;
static size_t n = 0;
const size_t n_max = fs_kHz/FREQ_STEP_KHZ;
#if 0
@ -652,30 +670,7 @@ static void shift_freq_50(float *i, float *q, int fs_kHz)
n += ft/FREQ_STEP_KHZ;
#endif
//fprintf(stdout, "%ld, %ld: %f, %f\n", n, n_max, crealf(freq_shift), cimagf(freq_shift));
if (n >= n_max) n = 0;
float complex s = (*i) + (*q) * _Complex_I;
s = s * freq_shift;
*i = crealf(s);
*q = cimagf(s);
}
/* Positive frequencies shift: ft = 200kHz the signal will shift from 868.7M right to 868.9M. */
static void shift_freq_200(float *i, float *q, int fs_kHz)
{
const int ft = 200;
static size_t n = 0;
const size_t n_max = fs_kHz/FREQ_STEP_KHZ;
#if 0
const float complex freq_shift = cosf(2.*M_PI*(ft*n)/fs_kHz) - sin(2.*M_PI*(ft*n)/fs_kHz) * _Complex_I;
n++;
#else
const float complex freq_shift = LUT_FREQUENCY_TRANSLATION_PLUS[n];
n += ft/FREQ_STEP_KHZ;
#endif
//fprintf(stdout, "%ld, %ld: %f, %f\n", n, n_max, crealf(freq_shift), cimagf(freq_shift));
if (n >= n_max) n = 0;
if (n >= n_max) n -= n_max;
float complex s = (*i) + (*q) * _Complex_I;
s = s * freq_shift;
@ -698,7 +693,7 @@ static void shift_freq_minus400(float *i, float *q, int fs_kHz)
n += ft/FREQ_STEP_KHZ;
#endif
//fprintf(stdout, "%ld, %ld: %f, %f\n", n, n_max, crealf(freq_shift), cimagf(freq_shift));
if (n >= n_max) n = 0;
if (n >= n_max) n -= n_max;
float complex s = (*i) + (*q) * _Complex_I;
s = s * freq_shift;
@ -756,7 +751,7 @@ int main(int argc, char *argv[])
if (1 != read_items)
{
// End of file?..
return 2;
break;
}
for (size_t k = 0; k < sizeof(samples)/sizeof(samples[0]); k += 2) // +2 : i and q interleaved
@ -775,8 +770,7 @@ int main(int argc, char *argv[])
if (opts_s1_t1_c1_simultaneously)
{
shift_freq_200(&i_t1_c1_unfilt, &q_t1_c1_unfilt, fs_kHz);
shift_freq_50(&i_t1_c1_unfilt, &q_t1_c1_unfilt, fs_kHz);
shift_freq_250(&i_t1_c1_unfilt, &q_t1_c1_unfilt, fs_kHz);
shift_freq_minus400(&i_s1_unfilt, &q_s1_unfilt, fs_kHz);
}
@ -788,8 +782,11 @@ int main(int argc, char *argv[])
// which must not be divided by decimation factor before
// demodulating (atan2(q,i)).
#if 0
i = lp_fir_butter_1600kHz_160kHz_200kHz(i_unfilt, 0);
q = lp_fir_butter_1600kHz_160kHz_200kHz(q_unfilt, 1);
i_t1_c1 = lp_fir_butter_1600kHz_160kHz_200kHz_t1_c1(i_t1_c1_unfilt, 0);
q_t1_c1 = lp_fir_butter_1600kHz_160kHz_200kHz_t1_c1(q_t1_c1_unfilt, 1);
i_s1 = lp_fir_butter_1600kHz_160kHz_200kHz_s1(i_s1_unfilt, 0);
q_s1 = lp_fir_butter_1600kHz_160kHz_200kHz_s1(q_s1_unfilt, 1);
#elif 0
i = lp_ppf_butter_1600kHz_160kHz_200kHz(i_unfilt, 0);
q = lp_ppf_butter_1600kHz_160kHz_200kHz(q_unfilt, 1);

4
samples/notice.txt
Wyświetl plik

@ -1 +1,3 @@
The sample rate of all recordings is 1.6Msamples if nothing else is mentioned in the filename.
The sample rate of all recordings is 1.6 MSamples/sec if nothing else is mentioned in the filename.
The rx frequency is 868.95MHz if nothing else is mentioned in the filename.