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Adding_WFM_AM_mode_to_Audio_App (#2644)

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* Adding_WFM_AM_mode_to_Audio_App
* more precise values for cos and sin theta, fix sen_theta to sin_theta
* fix sen_theta to sin_theta
This commit is contained in:
Brumi-2021
2025-05-05 17:48:01 +02:00
committed by GitHub
parent bd781ce37b
commit 4342f5c0ee
18 changed files with 448 additions and 49 deletions
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firmware/common/dsp_fir_taps.hpp
+122
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@@ -1325,6 +1325,128 @@ constexpr fir_taps_real<16> taps_40k_wfm_decim_1 = {
}},
};
// WFMAM decimation filters ////////////////////////////////////////////////
// Used for NOAA 137 Mhz APT sat demod.
// IFIR prototype filter: fs=768000, pass=42000, stop=95000, decim=8, fout=96000
constexpr fir_taps_real<32> taps_84k_wfmam_decim_1 = {
.low_frequency_normalized = -42000.0f / 768000.0f,
.high_frequency_normalized = 42000.0f / 768000.0f,
.transition_normalized = 53000.0f / 768000.0f,
.taps = {{
13,
-6,
-47,
-116,
-207,
-294,
-332,
-266,
-39,
386,
1012,
1795,
2648,
3452,
4079,
4423,
4423,
4079,
3452,
2648,
1795,
1012,
386,
-39,
-266,
-332,
-294,
-207,
-116,
-47,
-6,
13,
}},
};
/* 1st Wideband FM demod baseband filter of audio AM tones ,
to pass all DSB band of AM fsubcarrier 2.4Khz mod. with APT */
/* 24kHz int16_t input
* -> FIR filter, <4.5kHz (0.1875fs) pass, >5.2kHz (0.2166fs) stop
* -> 12kHz int16_t output, gain of 1.0 (I think).
* sum(abs(taps)): 125152 , before <125270>, very similar.
*/
constexpr fir_taps_real<64> taps_64_lp_1875_2166{
.low_frequency_normalized = -0.1875f,
.high_frequency_normalized = 0.1875f,
.transition_normalized = 0.03f,
.taps = {{
38,
-21,
-51,
-9,
77,
82,
-50,
-168,
-67,
190,
253,
-61,
-403,
-243,
356,
616,
15,
-814,
-671,
550,
1335,
334,
-1527,
-1689,
725,
2978,
1455,
-3277,
-5361,
830,
13781,
24549,
24549,
13781,
830,
-5361,
-3277,
1455,
2978,
725,
-1689,
-1527,
334,
1335,
550,
-671,
-814,
15,
616,
356,
-243,
-403,
-61,
253,
190,
-67,
-168,
-50,
82,
77,
-9,
-51,
-21,
38,
}},
};
// TPMS decimation filters ////////////////////////////////////////////////
// IFIR image-reject filter: fs=2457600, pass=100000, stop=407200, decim=4, fout=614400