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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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35
firmware/baseband/dsp_demodulate.cpp
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@@ -24,6 +24,8 @@
#include "complex.hpp"
#include "fxpt_atan2.hpp"
#include "utility_m4.hpp"
#include "dsp_hilbert.hpp"
#include "dsp_modulate.hpp"
#include <hal.h>
@@ -63,12 +65,7 @@ buffer_f32_t SSB::execute(
return {dst.p, src.count, src.sampling_rate};
}
/*
static inline float angle_approx_4deg0(const complex32_t t) {
const auto x = static_cast<float>(t.imag()) / static_cast<float>(t.real());
return 16384.0f * x;
}
*/
static inline float angle_approx_0deg27(const complex32_t t) {
if (t.real()) {
const auto x = static_cast<float>(t.imag()) / static_cast<float>(t.real());
@@ -82,6 +79,32 @@ static inline float angle_precise(const complex32_t t) {
return atan2f(t.imag(), t.real());
}
buffer_f32_t SSB_FM::execute( // Added to handle WFAX (HF weather map )-
const buffer_c16_t& src, // input arg , pointer Complex c16 i,q buffer.
const buffer_f32_t& dst) { // input arg , pointer f32 buffer audio demodulated
complex16_t* src_p = src.p; // removed const ; init src_p pointer with the mem address pointed by src.p.
const auto src_end = &src.p[src.count];
auto dst_p = dst.p;
float mag_sq_lpf_norm;
while (src_p < src_end) {
// FM APT audio tone demod: real part (USB-differentiator) and AM tone demodulation + lpf (to remove the subcarrier.)
real_to_complex.execute((src_p++)->real(), mag_sq_lpf_norm);
*(dst_p++) = mag_sq_lpf_norm; // already normalized/32.768f and clipped to +1.0f for the wav file.
real_to_complex.execute((src_p++)->real(), mag_sq_lpf_norm);
*(dst_p++) = mag_sq_lpf_norm;
real_to_complex.execute((src_p++)->real(), mag_sq_lpf_norm);
*(dst_p++) = mag_sq_lpf_norm;
real_to_complex.execute((src_p++)->real(), mag_sq_lpf_norm);
*(dst_p++) = mag_sq_lpf_norm;
}
return {dst.p, src.count, src.sampling_rate};
}
buffer_f32_t FM::execute(
const buffer_c16_t& src,
const buffer_f32_t& dst) {