Extract NarrowbandFMAudio into separate files.

This commit is contained in:
Jared Boone 2015-08-27 13:14:45 -07:00
parent e246ea2c39
commit 7c5db55f8f
4 changed files with 125 additions and 61 deletions

View file

@ -53,6 +53,7 @@
#include "channel_decimator.hpp"
#include "baseband_processor.hpp"
#include "proc_am_audio.hpp"
#include "proc_nfm_audio.hpp"
#include "clock_recovery.hpp"
#include "access_code_correlator.hpp"
@ -78,67 +79,6 @@
constexpr auto baseband_thread_priority = NORMALPRIO + 20;
constexpr auto rssi_thread_priority = NORMALPRIO + 10;
class NarrowbandFMAudio : public BasebandProcessor {
public:
void execute(buffer_c8_t buffer) override {
/* Called every 2048/3072000 second -- 1500Hz. */
auto decimator_out = decimator.execute(buffer);
const buffer_c16_t work_baseband_buffer {
(complex16_t*)decimator_out.p,
sizeof(*decimator_out.p) * decimator_out.count
};
/* 96kHz complex<int16_t>[64]
* -> FIR filter, <6kHz (0.063fs) pass, gain 1.0
* -> 48kHz int16_t[32] */
auto channel = channel_filter.execute(decimator_out, work_baseband_buffer);
// TODO: Feed channel_stats post-decimation data?
feed_channel_stats(channel);
feed_channel_spectrum(
channel,
decimator_out.sampling_rate * channel_filter_taps.pass_frequency_normalized,
decimator_out.sampling_rate * channel_filter_taps.stop_frequency_normalized
);
const buffer_s16_t work_audio_buffer {
(int16_t*)decimator_out.p,
sizeof(*decimator_out.p) * decimator_out.count
};
/* 48kHz complex<int16_t>[32]
* -> FM demodulation
* -> 48kHz int16_t[32] */
auto audio = demod.execute(channel, work_audio_buffer);
static uint64_t audio_present_history = 0;
const auto audio_present_now = squelch.execute(audio);
audio_present_history = (audio_present_history << 1) | (audio_present_now ? 1 : 0);
const bool audio_present = (audio_present_history != 0);
if( !audio_present ) {
// Zero audio buffer.
for(size_t i=0; i<audio.count; i++) {
audio.p[i] = 0;
}
}
audio_hpf.execute_in_place(audio);
fill_audio_buffer(audio);
}
private:
ChannelDecimator decimator { ChannelDecimator::DecimationFactor::By32 };
const fir_taps_real<64>& channel_filter_taps = taps_64_lp_042_078_tfilter;
dsp::decimate::FIRAndDecimateBy2Complex<64> channel_filter { channel_filter_taps.taps };
dsp::demodulate::FM demod { 48000, 7500 };
IIRBiquadFilter audio_hpf { audio_hpf_config };
FMSquelch squelch;
};
class WidebandFMAudio : public BasebandProcessor {
public:
void execute(buffer_c8_t buffer) override {