Started work on ACARS RX

Added ACARS frequencies file
Moved non-implemented apps menu items down

firmware/baseband/CMakeLists.txt

@@ -277,6 +277,13 @@ macro(DeclareTargets chunk_tag name)
 	set(BASEBAND_IMAGES ${BASEBAND_IMAGES} ${PROJECT_NAME}.img)
 endmacro()
 
+### ACARS RX
+
+set(MODE_CPPSRC
+	proc_acars.cpp
+)
+DeclareTargets(PACA acars)
+
 ### ADS-B RX
 
 set(MODE_CPPSRC

firmware/baseband/proc_acars.cpp

@@ -0,0 +1,73 @@
+/*
+ * 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.
+ */
+
+#include "proc_acars.hpp"
+
+#include "portapack_shared_memory.hpp"
+
+#include "dsp_fir_taps.hpp"
+
+#include "event_m4.hpp"
+
+ACARSProcessor::ACARSProcessor() {
+	decim_0.configure(taps_11k0_decim_0.taps, 33554432);
+	decim_1.configure(taps_11k0_decim_1.taps, 131072);
+}
+
+void ACARSProcessor::execute(const buffer_c8_t& buffer) {
+	/* 2.4576MHz, 2048 samples */
+
+	const auto decim_0_out = decim_0.execute(buffer, dst_buffer);
+	const auto decim_1_out = decim_1.execute(decim_0_out, dst_buffer);
+	const auto decimator_out = decim_1_out;
+
+	/* 38.4kHz, 32 samples */
+	feed_channel_stats(decimator_out);
+
+	for(size_t i=0; i<decimator_out.count; i++) {
+		if( mf.execute_once(decimator_out.p[i]) ) {
+			clock_recovery(mf.get_output());
+		}
+	}
+}
+
+void ACARSProcessor::consume_symbol(
+	const float raw_symbol
+) {
+	const uint_fast8_t sliced_symbol = (raw_symbol >= 0.0f) ? 1 : 0;
+	const auto decoded_symbol = nrzi_decode(sliced_symbol);
+
+	packet_builder.execute(decoded_symbol);
+}
+
+void ACARSProcessor::payload_handler(
+	const baseband::Packet& packet
+) {
+	const ACARSPacketMessage message { packet };
+	shared_memory.application_queue.push(message);
+}
+
+int main() {
+	EventDispatcher event_dispatcher { std::make_unique<ACARSProcessor>() };
+	event_dispatcher.run();
+	return 0;
+}

firmware/baseband/proc_acars.hpp

@@ -0,0 +1,98 @@
+/*
+ * 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 "dsp_demodulate.hpp"
+//#include "audio_compressor.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>
+
+#include "ais_baseband.hpp"
+
+class ACARSProcessor : public BasebandProcessor {
+public:
+	ACARSProcessor();
+
+	void execute(const buffer_c8_t& buffer) override;
+
+private:
+	static constexpr size_t baseband_fs = 2457600;
+
+	BasebandThread baseband_thread { baseband_fs, this, NORMALPRIO + 20, baseband::Direction::Receive };
+	RSSIThread rssi_thread { NORMALPRIO + 10 };
+
+	std::array<complex16_t, 512> dst { };
+	const buffer_c16_t dst_buffer {
+		dst.data(),
+		dst.size()
+	};
+
+	dsp::decimate::FIRC8xR16x24FS4Decim8 decim_0 { };
+	dsp::decimate::FIRC16xR16x32Decim8 decim_1 { };
+	dsp::matched_filter::MatchedFilter mf { baseband::ais::square_taps_38k4_1t_p, 2 };
+
+	clock_recovery::ClockRecovery<clock_recovery::FixedErrorFilter> clock_recovery {
+		19200, 2400, { 0.0555f },
+		[this](const float symbol) { this->consume_symbol(symbol); }
+	};
+	symbol_coding::NRZIDecoder nrzi_decode { };
+	PacketBuilder<BitPattern, NeverMatch, BitPattern> packet_builder {
+		{ 0b1001011010010110, 16, 1 },	// SYN, SYN
+		{ },
+		{ 0b11111111, 8, 1 },
+		[this](const baseband::Packet& packet) {
+			this->payload_handler(packet);
+		}
+	};
+
+	void consume_symbol(const float symbol);
+	void payload_handler(const baseband::Packet& packet);
+};
+
+#endif/*__PROC_ACARS_H__*/