portapack-mayhem/firmware/baseband/proc_acars.hpp

148 lines
4.4 KiB
C++

/*
* Copyright (C) 2014 Jared Boone, ShareBrained Technology, Inc.
* Copyright (C) 2018 Furrtek
*
* 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 __PROC_ACARS_H__
#define __PROC_ACARS_H__
#include "baseband_processor.hpp"
#include "baseband_thread.hpp"
#include "rssi_thread.hpp"
#include "dsp_decimate.hpp"
#include "spectrum_collector.hpp"
#include <cstdint>
#include "baseband_processor.hpp"
#include "baseband_thread.hpp"
#include "rssi_thread.hpp"
#include "channel_decimator.hpp"
#include "matched_filter.hpp"
#include "clock_recovery.hpp"
#include "symbol_coding.hpp"
#include "packet_builder.hpp"
#include "baseband_packet.hpp"
#include "message.hpp"
#include <cstdint>
#include <cstddef>
#include <bitset>
// AIS:
// IN: 2457600/8/8 = 38400
// Offset: 2457600/4 = 614400 (614400/8/8 = 9600)
// Deviation: 2400
// Symbol: 9600
// Decimate: 2
// 4 taps, 1 symbol, 1/4 cycle
// TPMS:
// IN: 2457600/4/2 = 307200
// Offset: 2457600/4 = 614400 (614400/4/2 = 76800)
// Deviation: 38400
// Symbol: 19200
// Decimate: 8
// 16 taps, 1 symbol, 2 cycles
// ACARS:
// IN: 2457600/8/8 = 38400
// Offset: 2457600/4 = 614400 (614400/8/8 = 9600)
// Deviation: ???
// Symbol: 2400
// Decimate: 8
// 16 taps, 1 symbol, 2 cycles
// Number of taps: size of one symbol in samples (in/symbol)
// Cycles:
// Translate+rectangular filter
// sample=38.4k, deviation=4800, symbol=2400
// Length: 16 taps, 1 symbol, 2 cycles of sinusoid
// This is actually the same as rect_taps_307k2_38k4_1t_19k2_p
constexpr std::array<std::complex<float>, 16> rect_taps_38k4_4k8_1t_2k4_p{{
{6.2500000000e-02f, 0.0000000000e+00f},
{4.4194173824e-02f, 4.4194173824e-02f},
{0.0000000000e+00f, 6.2500000000e-02f},
{-4.4194173824e-02f, 4.4194173824e-02f},
{-6.2500000000e-02f, 0.0000000000e+00f},
{-4.4194173824e-02f, -4.4194173824e-02f},
{0.0000000000e+00f, -6.2500000000e-02f},
{4.4194173824e-02f, -4.4194173824e-02f},
{6.2500000000e-02f, 0.0000000000e+00f},
{4.4194173824e-02f, 4.4194173824e-02f},
{0.0000000000e+00f, 6.2500000000e-02f},
{-4.4194173824e-02f, 4.4194173824e-02f},
{-6.2500000000e-02f, 0.0000000000e+00f},
{-4.4194173824e-02f, -4.4194173824e-02f},
{0.0000000000e+00f, -6.2500000000e-02f},
{4.4194173824e-02f, -4.4194173824e-02f},
}};
class ACARSProcessor : public BasebandProcessor {
public:
ACARSProcessor();
void execute(const buffer_c8_t& buffer) override;
private:
static constexpr size_t baseband_fs = 2457600;
std::array<complex16_t, 512> dst{};
const buffer_c16_t dst_buffer{
dst.data(),
dst.size()};
dsp::decimate::FIRC8xR16x24FS4Decim8 decim_0{}; // Translate already done here !
dsp::decimate::FIRC16xR16x32Decim8 decim_1{};
dsp::matched_filter::MatchedFilter mf{rect_taps_38k4_4k8_1t_2k4_p, 8};
clock_recovery::ClockRecovery<clock_recovery::FixedErrorFilter> clock_recovery{
4800,
2400,
{0.0555f},
[this](const float symbol) { this->consume_symbol(symbol); }};
symbol_coding::ACARSDecoder acars_decode{};
/*PacketBuilder<BitPattern, NeverMatch, FixedLength> packet_builder {
{ 0b011010000110100010000000, 24, 1 }, // SYN, SYN, SOH
{ },
{ 128 },
[this](const baseband::Packet& packet) {
this->payload_handler(packet);
}
};*/
baseband::Packet packet{};
/* NB: Threads should be the last members in the class definition. */
BasebandThread baseband_thread{
baseband_fs, this, baseband::Direction::Receive, /*auto_start*/ false};
RSSIThread rssi_thread{};
void consume_symbol(const float symbol);
void payload_handler(const baseband::Packet& packet);
};
#endif /*__PROC_ACARS_H__*/