From de0777f476f748e09dd27cadec15aaac656b4780 Mon Sep 17 00:00:00 2001 From: Jared Boone Date: Thu, 27 Aug 2015 09:59:03 -0700 Subject: [PATCH] Extract FMSquelch into separate files. --- firmware/baseband/Makefile | 1 + firmware/baseband/dsp_squelch.cpp | 45 +++++++++++++++++++++++++++++++ firmware/baseband/dsp_squelch.hpp | 45 +++++++++++++++++++++++++++++++ firmware/baseband/main.cpp | 32 +--------------------- 4 files changed, 92 insertions(+), 31 deletions(-) create mode 100644 firmware/baseband/dsp_squelch.cpp create mode 100644 firmware/baseband/dsp_squelch.hpp diff --git a/firmware/baseband/Makefile b/firmware/baseband/Makefile index ee221a64..7ef76869 100755 --- a/firmware/baseband/Makefile +++ b/firmware/baseband/Makefile @@ -132,6 +132,7 @@ CPPSRC = main.cpp \ channel_decimator.cpp \ dsp_decimate.cpp \ dsp_demodulate.cpp \ + dsp_squelch.cpp \ clock_recovery.cpp \ access_code_correlator.cpp \ packet_builder.cpp \ diff --git a/firmware/baseband/dsp_squelch.cpp b/firmware/baseband/dsp_squelch.cpp new file mode 100644 index 00000000..4cfe651a --- /dev/null +++ b/firmware/baseband/dsp_squelch.cpp @@ -0,0 +1,45 @@ +/* + * Copyright (C) 2015 Jared Boone, ShareBrained Technology, Inc. + * + * This file is part of PortaPack. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2, or (at your option) + * any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; see the file COPYING. If not, write to + * the Free Software Foundation, Inc., 51 Franklin Street, + * Boston, MA 02110-1301, USA. + */ + +#include "dsp_squelch.hpp" + +#include +#include + +bool FMSquelch::execute(buffer_s16_t audio) { + // TODO: No hard-coded array size. + std::array squelch_energy_buffer; + const buffer_s16_t squelch_energy { + squelch_energy_buffer.data(), + squelch_energy_buffer.size() + }; + non_audio_hpf.execute(audio, squelch_energy); + + uint64_t max_squared = 0; + for(const auto sample : squelch_energy_buffer) { + const uint64_t sample_squared = sample * sample; + if( sample_squared > max_squared ) { + max_squared = sample_squared; + } + } + + return (max_squared < (threshold * threshold)); +} diff --git a/firmware/baseband/dsp_squelch.hpp b/firmware/baseband/dsp_squelch.hpp new file mode 100644 index 00000000..06cb2cdd --- /dev/null +++ b/firmware/baseband/dsp_squelch.hpp @@ -0,0 +1,45 @@ +/* + * Copyright (C) 2015 Jared Boone, ShareBrained Technology, Inc. + * + * This file is part of PortaPack. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2, or (at your option) + * any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; see the file COPYING. If not, write to + * the Free Software Foundation, Inc., 51 Franklin Street, + * Boston, MA 02110-1301, USA. + */ + +#ifndef __DSP_SQUELCH_H__ +#define __DSP_SQUELCH_H__ + +#include "buffer.hpp" +#include "dsp_iir.hpp" +#include "dsp_iir_config.hpp" + +#include +#include + +class FMSquelch { +public: + bool execute(buffer_s16_t audio); + +private: + static constexpr size_t N = 32; + static constexpr int16_t threshold = 3072; + + // nyquist = 48000 / 2.0 + // scipy.signal.iirdesign(wp=8000 / nyquist, ws= 4000 / nyquist, gpass=1, gstop=18, ftype='ellip') + IIRBiquadFilter non_audio_hpf { non_audio_hpf_config }; +}; + +#endif/*__DSP_SQUELCH_H__*/ diff --git a/firmware/baseband/main.cpp b/firmware/baseband/main.cpp index 4545d07e..c3d9f3f7 100755 --- a/firmware/baseband/main.cpp +++ b/firmware/baseband/main.cpp @@ -46,6 +46,7 @@ #include "dsp_fir_taps.hpp" #include "dsp_iir.hpp" #include "dsp_iir_config.hpp" +#include "dsp_squelch.hpp" #include "baseband_stats_collector.hpp" #include "rssi_stats_collector.hpp" @@ -79,37 +80,6 @@ constexpr auto baseband_thread_priority = NORMALPRIO + 20; constexpr auto rssi_thread_priority = NORMALPRIO + 10; -class FMSquelch { -public: - bool execute(buffer_s16_t audio) { - // TODO: No hard-coded array size. - std::array squelch_energy_buffer; - const buffer_s16_t squelch_energy { - squelch_energy_buffer.data(), - squelch_energy_buffer.size() - }; - non_audio_hpf.execute(audio, squelch_energy); - - uint64_t max_squared = 0; - for(const auto sample : squelch_energy_buffer) { - const uint64_t sample_squared = sample * sample; - if( sample_squared > max_squared ) { - max_squared = sample_squared; - } - } - - return (max_squared < (threshold * threshold)); - } - -private: - static constexpr size_t N = 32; - static constexpr int16_t threshold = 3072; - - // nyquist = 48000 / 2.0 - // scipy.signal.iirdesign(wp=8000 / nyquist, ws= 4000 / nyquist, gpass=1, gstop=18, ftype='ellip') - IIRBiquadFilter non_audio_hpf { non_audio_hpf_config }; -}; - static volatile bool channel_spectrum_request_update { false }; static std::array channel_spectrum; static uint32_t channel_spectrum_sampling_rate { 0 };