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Adding Wefax demodulation mode inside Audio App (#2539)

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* Adding_new_WFAX_GUI_mode_Audio_App

* Wefax_APT_demodulation_structure

* Solving REC Apt signal.wav from WFAX

* clang format issues

* correcting comments
This commit is contained in:
Brumi-2021
2025-03-05 04:27:18 +01:00
committed by GitHub
parent b6e498a6d3
commit 52c3760e90
19 changed files with 383 additions and 55 deletions
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firmware/common/dsp_fir_taps.hpp
+86 -10
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@@ -553,14 +553,14 @@ constexpr fir_taps_real<32> taps_6k0_decim_2{
}},
};
// IFIR prototype filter fs=48000 ; pass=4500 (cutt off -3dBs) , stop=8000 (<-60dBs), decim=4, fout=12000
// IFIR prototype filter fs=48000 ; pass=4500 (cutoff -3dBs) , stop=8000 (<-60dBs), decim=4, fout=12000
// For Europe AM commercial broadcasting stations in LF/MF/HF, Emissions Designator 9K00A3E Bandwidth: 9.00 kHz (derivated from taps_6k0_decim_2 )
// Pre-decimate LPF FIR filter design Created with SciPy Python with the "window method", num_taps = 32, cut_off = 5150. sample_rate = 48000 # Hz,
// Created with h = signal.firwin(num_taps, cut_off, nyq=sample_rate/2, window=('chebwin',50)) , achieving good STOP band plot < -60 dB's with some ripple.
// Pre-decimate LPF FIR filter design Created with SciPy Python with the "window method", num_taps = 32, cutoff = 5150. sample_rate = 48000 # Hz,
// Created with h = signal.firwin(num_taps, cutoff, nyq=sample_rate/2, window=('chebwin',50)) , achieving good STOP band plot < -60 dB's with some ripple.
// post-scaled h taps to avoid decimals , targeting <= similar int values as previous taps_6k0_dsb_channel peak < 32.767 (2 exp 15) and similar H(f)gain
constexpr fir_taps_real<32> taps_9k0_decim_2{
.low_frequency_normalized = -4500.0f / 48000.0f, // Negative -cutt off freq -3dB (real achieved data ,in the plot and measurements)
.high_frequency_normalized = 4500.0f / 48000.0f, // Positive +cutt off freq -3dB (idem)
.low_frequency_normalized = -4500.0f / 48000.0f, // Negative -cutoff freq -3dB (real achieved data ,in the plot and measurements)
.high_frequency_normalized = 4500.0f / 48000.0f, // Positive +cutoff freq -3dB (idem)
.transition_normalized = 3500.0f / 48000.0f, // 3500 Hz = (8000 Hz - 4500 Hz) (both from plot H(f) curve plot)
.taps = {{-53, -30, 47, 198, 355, 372, 89, -535,
-1307, -1771, -1353, 370, 3384, 7109, 10535, 12591,
@@ -644,14 +644,14 @@ constexpr fir_taps_complex<64> taps_6k0_dsb_channel{
}},
};
// Channel filter: fs=12000, pass=4500 (cutt off -3dBs), stop=4940 (<-60dBs), decim=1, fout=12000 (*1) real frec pass / stop , based on plotted H(f) curve)
// Channel filter: fs=12000, pass=4500 (cutoff -3dBs), stop=4940 (<-60dBs), decim=1, fout=12000 (*1) real frec pass / stop , based on plotted H(f) curve)
// For Europe AM commercial broadcasting stations in LF/MF/HF, Emissions Designator 9K00A3E Bandwidth: 9.00 kHz (derivative from taps_6k0_dsb_channel)
// FIR filter design created with SciPy Python using "window method"; selected design parameters: num_taps = 64, cut_off = 4575. sample_rate = 12000 # Hz,
// Created with : h = signal.firwin(num_taps, cut_off, nyq=sample_rate/2, window=('chebwin',50)) , achieving real plot curve (*1) with peak stop band ripple -60dBs.
// FIR filter design created with SciPy Python using "window method"; selected design parameters: num_taps = 64, cutoff = 4575. sample_rate = 12000 # Hz,
// Created with : h = signal.firwin(num_taps, cutoff, nyq=sample_rate/2, window=('chebwin',50)) , achieving real plot curve (*1) with peak stop band ripple -60dBs.
// post-scaled h taps to avoid decimals , targeting <= similar int values as previous taps_6k0_dsb_channel peak < 32.767 (2 exp 15), (29625) and similar H(f)gain
constexpr fir_taps_complex<64> taps_9k0_dsb_channel{
.low_frequency_normalized = -4500.0f / 12000.0f, // Negative -cutt off freq -3dB (in the H(f) curve plot)
.high_frequency_normalized = 4500.0f / 12000.0f, // Positive +cutt off freq -3dB (in the H(f) curve plot)
.low_frequency_normalized = -4500.0f / 12000.0f, // Negative -cutoff freq -3dB (in the H(f) curve plot)
.high_frequency_normalized = 4500.0f / 12000.0f, // Positive +cutoff freq -3dB (in the H(f) curve plot)
.transition_normalized = 440.0f / 12000.0f, // 440Hz = (4940 Hz -4500 Hz) cut-3dB's (both data comes from H(f) curve plot and confirmed by measurements )
.taps = {{
{2, 0},
@@ -945,6 +945,82 @@ constexpr fir_taps_complex<64> taps_0k7_usb_channel{
}},
};
// USB AM+FM for Wefax (Weather fax RX) , based USB AM with truncated Differentiator band limmited cuttoff 2.400Hz for Audio Tones FM dem. ///////////////////
// IFIR prototype filter: fs=12000, pass=2600, stop=3200, decim=1, fout=12000 // stop band minimum att < -48 dB's (+3300 Hz min atten peak) , rest <50 to -60dB's
constexpr fir_taps_complex<64> taps_2k6_usb_wefax_channel{
.low_frequency_normalized = 0,
.high_frequency_normalized = 2600.0f / 12000.0f,
.transition_normalized = 600.0f / 12000.0f,
.taps = {{{-14 + 2},
{-11 - 5},
{-2 - 8},
{6 - 5},
{13 + 1},
{15 + 14},
{0 + 26},
{-22 + 13},
{-13 - 11},
{7 - 1},
{-20 + 17},
{-47 - 37},
{33 - 89},
{122 + 8},
{19 + 131},
{-124 + 26},
{1 - 123},
{158 + 52},
{-94 + 245},
{-363 - 91},
{36 - 468},
{524 - 37},
{67 + 531},
{-552 + 5},
{136 - 686},
{1013 + 258},
{-204 + 1527},
{-2104 + 168},
{-900 - 2529},
{2577 - 1881},
{2868 + 2122},
{-1209 + 3570},
{-3768 - 52},
{-1043 - 3412},
{2634 - 1801},
{2083 + 1693},
{-861 + 1927},
{-1507 - 318},
{95 - 1041},
{692 + 100},
{-189 + 519},
{-478 - 241},
{210 - 481},
{454 + 122},
{-35 + 372},
{-262 + 7},
{4 - 166},
{116 + 40},
{-66 + 108},
{-117 - 62},
{33 - 117},
{95 - 2},
{19 + 57},
{-23 + 13},
{3 - 7},
{6 + 16},
{-20 + 16},
{-25 - 9},
{-8 - 19},
{4 - 12},
{7 - 4},
{7 + 4},
{2 + 12},
{-7 + 13}
}}
};
// WFM 200KF8E emission type //////////////////////////////////////////////
// IFIR image-reject filter: fs=3072000, pass=100000, stop=484000, decim=4, fout=768000