mirror of
https://github.com/portapack-mayhem/mayhem-firmware.git
synced 2024-12-14 20:18:13 +00:00
339 lines
16 KiB
C++
339 lines
16 KiB
C++
/*
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* Copyright (C) 2015 Jared Boone, ShareBrained Technology, Inc.
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*
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* This file is part of PortaPack.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2, or (at your option)
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* any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; see the file COPYING. If not, write to
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* the Free Software Foundation, Inc., 51 Franklin Street,
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* Boston, MA 02110-1301, USA.
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*/
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#ifndef __AIS_BASEBAND_H__
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#define __AIS_BASEBAND_H__
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#include "crc.hpp"
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#include <cstdint>
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#include <cstddef>
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#include <complex>
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#include <array>
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#include <bitset>
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namespace baseband {
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template<typename T, typename BitRemap>
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class FieldReader {
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public:
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constexpr FieldReader(
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const T& data
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) : data { data }
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{
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}
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uint32_t read(const size_t start_bit, const size_t length) const {
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uint32_t value = 0;
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for(size_t i=start_bit; i<(start_bit + length); i++) {
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value = (value << 1) | data[bit_remap(i)];
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}
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return value;
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}
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private:
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const T& data;
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const BitRemap bit_remap { };
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};
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namespace ais {
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// RRC length should be about 4 x the symbol length to do a good job of
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// cleaning up ISI.
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/*
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constexpr std::array<std::complex<float>, 8> rrc_taps_8_p { {
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{ 0.00533687f, 0.00000000f }, { -0.00667109f, 0.00667109f },
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{ 0.00000000f, 0.01334218f }, { -0.05145006f, -0.05145006f },
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{ -0.14292666f, 0.00000000f }, { -0.05145006f, 0.05145006f },
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{ 0.00000000f, -0.01334218f }, { -0.00667109f, -0.00667109f },
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} };
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*/
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//
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// These came from GRC directly, and have a bit more gain, it appears.
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//
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constexpr std::array<std::complex<float>, 8> rrc_taps_128_decim_16_p { {
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{ 2.1046938375e-02f, 0.0000000000e+00f }, { -2.6308671336e-02f, -2.6308671336e-02f },
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{ -3.2218829289e-18f, -5.2617341280e-02f }, { -2.0290270482e-01f, 2.0290270482e-01f },
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{ -5.6365746260e-01f, 6.9028130738e-17f }, { -2.0290270482e-01f, -2.0290270482e-01f },
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{ 9.6656487867e-18f, 5.2617341280e-02f }, { -2.6308671336e-02f, 2.6308671336e-02f },
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} };
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constexpr std::array<std::complex<float>, 16> rrc_taps_128_decim_8_p { {
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{ -5.0682835281e-03f, 0.0000000000e+00f }, { 3.8012127427e-03f, 3.8012127427e-03f },
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{ 9.3102863700e-20f, 1.5204851516e-03f }, { 5.3216978397e-03f, -5.3216978397e-03f },
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{ -2.1286793053e-02f, 2.6068802977e-18f }, { 2.6608490845e-02f, 2.6608490845e-02f },
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{ 9.7758004319e-18f, 5.3216978908e-02f }, { 2.0521502845e-01f, -2.0521502845e-01f },
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{ 5.7008099556e-01f, -1.3962957329e-16f }, { 2.0521502845e-01f, 2.0521502845e-01f },
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{ -1.6293000720e-17f, -5.3216978908e-02f }, { 2.6608490845e-02f, -2.6608490845e-02f },
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{ -2.1286793053e-02f, 7.8206408930e-18f }, { 5.3216978397e-03f, 5.3216978397e-03f },
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{ -6.5172004590e-19f, -1.5204851516e-03f }, { 3.8012127427e-03f, -3.8012127427e-03f },
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} };
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constexpr std::array<std::complex<float>, 32> rrc_taps_128_decim_4_p { {
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{ -1.2495006667e-03f, 0.0000000000e+00f }, { 7.5862532786e-04f, 7.5862532786e-04f },
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{ 7.1465238505e-21f, 1.1671159155e-04f }, { 8.7533694842e-04f, -8.7533694842e-04f },
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{ -2.2281305864e-03f, 2.7286729908e-19f }, { 1.4482847468e-03f, 1.4482847468e-03f },
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{ 5.9121245638e-20f, 3.2184107113e-04f }, { 1.7701258199e-03f, -1.7701258199e-03f },
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{ -5.0575020723e-03f, 1.2387307449e-18f }, { 3.7931268039e-03f, 3.7931268039e-03f },
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{ 4.6452407924e-19f, 1.5172507847e-03f }, { 5.3103774596e-03f, -5.3103774596e-03f },
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{ -2.1241510287e-02f, 7.8040042746e-18f }, { 2.6551890262e-02f, 2.6551890262e-02f },
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{ 2.2761678735e-17f, 5.3103774786e-02f }, { 2.0477849246e-01f, -2.0477849246e-01f },
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{ 5.6886833906e-01f, -2.7866511623e-16f }, { 2.0477849246e-01f, 2.0477849246e-01f },
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{ -2.9265015516e-17f, -5.3103774786e-02f }, { 2.6551890262e-02f, -2.6551890262e-02f },
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{ -2.1241510287e-02f, 1.3006673791e-17f }, { 5.3103774596e-03f, 5.3103774596e-03f },
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{ -3.7171317828e-18f, -1.5172507847e-03f }, { 3.7931268039e-03f, -3.7931268039e-03f },
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{ -5.0575020723e-03f, 3.7161922347e-18f }, { 1.7701258199e-03f, 1.7701258199e-03f },
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{ 3.1551252346e-19f, -3.2184107113e-04f }, { 1.4482847468e-03f, -1.4482847468e-03f },
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{ -2.2281305864e-03f, 1.9100710935e-18f }, { 8.7533694842e-04f, 8.7533694842e-04f },
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{ -3.1451929164e-19f, -1.1671159155e-04f }, { 7.5862532786e-04f, -7.5862532786e-04f },
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} };
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constexpr std::array<std::complex<float>, 64> rrc_taps_128_decim_2_p { {
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{ -6.2437308952e-04f, 0.0000000000e+00f }, { -2.2010185825e-04f, -9.1169174792e-05f },
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{ 3.7908365508e-04f, 3.7908365508e-04f }, { 2.8756602409e-04f, 6.9424579543e-04f },
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{ 3.5711042529e-21f, 5.8320558310e-05f }, { 2.8756602409e-04f, -6.9424579543e-04f },
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{ 4.3740419207e-04f, -4.3740419207e-04f }, { -3.9158988624e-04f, 1.6220184177e-04f },
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{ -1.1133925291e-03f, 1.3635125969e-19f }, { -3.9158988624e-04f, -1.6220184177e-04f },
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{ 7.2370509982e-04f, 7.2370509982e-04f }, { 5.6432127027e-04f, 1.3623920642e-03f },
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{ 2.9542774240e-20f, 1.6082337243e-04f }, { 5.6432127027e-04f, -1.3623920642e-03f },
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{ 8.8452850107e-04f, -8.8452850107e-04f }, { -8.8299684291e-04f, 3.6574926787e-04f },
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{ -2.5272241328e-03f, 6.1899138899e-19f }, { -8.8299684291e-04f, -3.6574926787e-04f },
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{ 1.8954181931e-03f, 1.8954181931e-03f }, { 1.5745747777e-03f, 3.8013597832e-03f },
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{ 2.3212178869e-19f, 7.5816729805e-04f }, { 1.5745747777e-03f, -3.8013597832e-03f },
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{ 2.6535855032e-03f, -2.6535855032e-03f }, { -3.5740348583e-03f, 1.4804137107e-03f },
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{ -1.0614342056e-02f, 3.8996460073e-18f }, { -3.5740348583e-03f, -1.4804137107e-03f },
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{ 1.3267928010e-02f, 1.3267928010e-02f }, { 1.5010946154e-02f, 3.6239629790e-02f },
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{ 1.1373966922e-17f, 2.6535853744e-02f }, { 1.5010946154e-02f, -3.6239629790e-02f },
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{ 1.0232741681e-01f, -1.0232741681e-01f }, { 2.2516419801e-01f, -9.3266064576e-02f },
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{ 2.8426241875e-01f, -1.3924842449e-16f }, { 2.2516419801e-01f, 9.3266064576e-02f },
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{ 1.0232741681e-01f, 1.0232741681e-01f }, { 1.5010946154e-02f, 3.6239629790e-02f },
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{ -1.4623671757e-17f, -2.6535853744e-02f }, { 1.5010946154e-02f, -3.6239629790e-02f },
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{ 1.3267928010e-02f, -1.3267928010e-02f }, { -3.5740348583e-03f, 1.4804137107e-03f },
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{ -1.0614342056e-02f, 6.4994100121e-18f }, { -3.5740348583e-03f, -1.4804137107e-03f },
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{ 2.6535855032e-03f, 2.6535855032e-03f }, { 1.5745747777e-03f, 3.8013597832e-03f },
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{ -1.8574436004e-18f, -7.5816729805e-04f }, { 1.5745747777e-03f, -3.8013597832e-03f },
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{ 1.8954181931e-03f, -1.8954181931e-03f }, { -8.8299684291e-04f, 3.6574926787e-04f },
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{ -2.5272241328e-03f, 1.8569741670e-18f }, { -8.8299684291e-04f, -3.6574926787e-04f },
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{ 8.8452850107e-04f, 8.8452850107e-04f }, { 5.6432127027e-04f, 1.3623920642e-03f },
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{ 1.5766100917e-19f, -1.6082337243e-04f }, { 5.6432127027e-04f, -1.3623920642e-03f },
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{ 7.2370509982e-04f, -7.2370509982e-04f }, { -3.9158988624e-04f, 1.6220184177e-04f },
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{ -1.1133925291e-03f, 9.5445881785e-19f }, { -3.9158988624e-04f, -1.6220184177e-04f },
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{ 4.3740419207e-04f, 4.3740419207e-04f }, { 2.8756602409e-04f, 6.9424579543e-04f },
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{ -1.5716468643e-19f, -5.8320558310e-05f }, { 2.8756602409e-04f, -6.9424579543e-04f },
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{ 3.7908365508e-04f, -3.7908365508e-04f }, { -2.2010185825e-04f, 9.1169174792e-05f },
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} };
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constexpr std::array<std::complex<float>, 128> rrc_taps_128_decim_1_p { {
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{ -3.1209018198e-04f, 0.0000000000e+00f }, { -2.5877077742e-04f, -5.1472707944e-05f },
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{ -1.1001696231e-04f, -4.5570517881e-05f }, { 6.6159029602e-05f, 4.4206050285e-05f },
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{ 1.8948331997e-04f, 1.8948331997e-04f }, { 2.1174839450e-04f, 3.1690386745e-04f },
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{ 1.4373864003e-04f, 3.4701577420e-04f }, { 4.7976800158e-05f, 2.4119566214e-04f },
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{ 1.7850010134e-21f, 2.9151278795e-05f }, { 3.9977422839e-05f, -2.0098007663e-04f },
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{ 1.4373864003e-04f, -3.4701577420e-04f }, { 2.3252332220e-04f, -3.4799574396e-04f },
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{ 2.1863459522e-04f, -2.1863459522e-04f }, { 6.2056194319e-05f, -4.1464623394e-05f },
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{ -1.9573451137e-04f, 8.1075889233e-05f }, { -4.4372297073e-04f, 8.8261986569e-05f },
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{ -5.5652443552e-04f, 6.8154586861e-20f }, { -4.6404687472e-04f, -9.2304662425e-05f },
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{ -1.9573451137e-04f, -8.1075889233e-05f }, { 1.2883682237e-04f, 8.6086012482e-05f },
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{ 3.6174088546e-04f, 3.6174088546e-04f }, { 4.0837232524e-04f, 6.1117237526e-04f },
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{ 2.8207356174e-04f, 6.8098581834e-04f }, { 9.7165906259e-05f, 4.8848599782e-04f },
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{ 1.4766828074e-20f, 8.0386867921e-05f }, { 7.5098076010e-05f, -3.7754352331e-04f },
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{ 2.8207356174e-04f, -6.8098581834e-04f }, { 4.6580996103e-04f, -6.9713387199e-04f },
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{ 4.4212772603e-04f, -4.4212772603e-04f }, { 1.1524044836e-04f, -7.7001205821e-05f },
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{ -4.4136215088e-04f, 1.8281818881e-04f }, { -9.9526783374e-04f, 1.9797108099e-04f },
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{ -1.2632220751e-03f, 3.0940017417e-19f }, { -1.0655584755e-03f, -2.1195275894e-04f },
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{ -4.4136215088e-04f, -1.8281818881e-04f }, { 3.4870278890e-04f, 2.3299575453e-04f },
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{ 9.4741662045e-04f, 9.4741662045e-04f }, { 1.0953310298e-03f, 1.6392787312e-03f },
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{ 7.8704441197e-04f, 1.9000932936e-03f }, { 2.9063040056e-04f, 1.4610976903e-03f },
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{ 1.1602507422e-19f, 3.7896665162e-04f }, { 1.8643098041e-04f, -9.3725183036e-04f },
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{ 7.8704441197e-04f, -1.9000932936e-03f }, { 1.3689220250e-03f, -2.0487365913e-03f },
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{ 1.3263832192e-03f, -1.3263832192e-03f }, { 2.3975916158e-04f, -1.6020195001e-04f },
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{ -1.7864658936e-03f, 7.3997840184e-04f }, { -4.0136172125e-03f, 7.9835810150e-04f },
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{ -5.3055332974e-03f, 1.9492213111e-18f }, { -4.6575086796e-03f, -9.2643607755e-04f },
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{ -1.7864658936e-03f, -7.3997840184e-04f }, { 2.5328987415e-03f, 1.6924288311e-03f },
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{ 6.6319165901e-03f, 6.6319165901e-03f }, { 8.6449647610e-03f, 1.2938104079e-02f },
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{ 7.5031564661e-03f, 1.8114222101e-02f }, { 3.7891721988e-03f, 1.9049455038e-02f },
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{ 5.6852282253e-18f, 1.3263831846e-02f }, { -3.6723852463e-05f, 1.8462327379e-04f },
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{ 7.5031564661e-03f, -1.8114222101e-02f }, { 2.4807723598e-02f, -3.7127382095e-02f },
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{ 5.1147919140e-02f, -5.1147919140e-02f }, { 8.2531291606e-02f, -5.5145646011e-02f },
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{ 1.1254735140e-01f, -4.6618639361e-02f }, { 1.3419687671e-01f, -2.6693418442e-02f },
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{ 1.4208734035e-01f, -6.9602722626e-17f }, { 1.3419687671e-01f, 2.6693418442e-02f },
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{ 1.1254735140e-01f, 4.6618639361e-02f }, { 8.2531291606e-02f, 5.5145646011e-02f },
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{ 5.1147919140e-02f, 5.1147919140e-02f }, { 2.4807723598e-02f, 3.7127382095e-02f },
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{ 7.5031564661e-03f, 1.8114222101e-02f }, { -3.6723852463e-05f, -1.8462327379e-04f },
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{ -7.3095791468e-18f, -1.3263831846e-02f }, { 3.7891721988e-03f, -1.9049455038e-02f },
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{ 7.5031564661e-03f, -1.8114222101e-02f }, { 8.6449647610e-03f, -1.2938104079e-02f },
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{ 6.6319165901e-03f, -6.6319165901e-03f }, { 2.5328987415e-03f, -1.6924288311e-03f },
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{ -1.7864658936e-03f, 7.3997840184e-04f }, { -4.6575086796e-03f, 9.2643607755e-04f },
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{ -5.3055332974e-03f, 3.2487021852e-18f }, { -4.0136172125e-03f, -7.9835810150e-04f },
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{ -1.7864658936e-03f, -7.3997840184e-04f }, { 2.3975916158e-04f, 1.6020195001e-04f },
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{ 1.3263832192e-03f, 1.3263832192e-03f }, { 1.3689220250e-03f, 2.0487365913e-03f },
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{ 7.8704441197e-04f, 1.9000932936e-03f }, { 1.8643098041e-04f, 9.3725183036e-04f },
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{ -9.2843516681e-19f, -3.7896665162e-04f }, { 2.9063040056e-04f, -1.4610976903e-03f },
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{ 7.8704441197e-04f, -1.9000932936e-03f }, { 1.0953310298e-03f, -1.6392787312e-03f },
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{ 9.4741662045e-04f, -9.4741662045e-04f }, { 3.4870278890e-04f, -2.3299575453e-04f },
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{ -4.4136215088e-04f, 1.8281818881e-04f }, { -1.0655584755e-03f, 2.1195275894e-04f },
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{ -1.2632220751e-03f, 9.2820052251e-19f }, { -9.9526783374e-04f, -1.9797108099e-04f },
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{ -4.4136215088e-04f, -1.8281818881e-04f }, { 1.1524044836e-04f, 7.7001205821e-05f },
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{ 4.4212772603e-04f, 4.4212772603e-04f }, { 4.6580996103e-04f, 6.9713387199e-04f },
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{ 2.8207356174e-04f, 6.8098581834e-04f }, { 7.5098076010e-05f, 3.7754352331e-04f },
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{ 7.8806174309e-20f, -8.0386867921e-05f }, { 9.7165906259e-05f, -4.8848599782e-04f },
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{ 2.8207356174e-04f, -6.8098581834e-04f }, { 4.0837232524e-04f, -6.1117237526e-04f },
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{ 3.6174088546e-04f, -3.6174088546e-04f }, { 1.2883682237e-04f, -8.6086012482e-05f },
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{ -1.9573451137e-04f, 8.1075889233e-05f }, { -4.6404687472e-04f, 9.2304662425e-05f },
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{ -5.5652443552e-04f, 4.7708210803e-19f }, { -4.4372297073e-04f, -8.8261986569e-05f },
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{ -1.9573451137e-04f, -8.1075889233e-05f }, { 6.2056194319e-05f, 4.1464623394e-05f },
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{ 2.1863459522e-04f, 2.1863459522e-04f }, { 2.3252332220e-04f, 3.4799574396e-04f },
|
|
{ 1.4373864003e-04f, 3.4701577420e-04f }, { 3.9977422839e-05f, 2.0098007663e-04f },
|
|
{ -7.8558088666e-20f, -2.9151278795e-05f }, { 4.7976800158e-05f, -2.4119566214e-04f },
|
|
{ 1.4373864003e-04f, -3.4701577420e-04f }, { 2.1174839450e-04f, -3.1690386745e-04f },
|
|
{ 1.8948331997e-04f, -1.8948331997e-04f }, { 6.6159029602e-05f, -4.4206050285e-05f },
|
|
{ -1.1001696231e-04f, 4.5570517881e-05f }, { -2.5877077742e-04f, 5.1472707944e-05f },
|
|
} };
|
|
|
|
struct BitRemap {
|
|
size_t operator()(const size_t bit_index) const {
|
|
return bit_index ^ 7;
|
|
}
|
|
};
|
|
|
|
struct CRCBitRemap {
|
|
size_t operator()(const size_t bit_index) const {
|
|
return bit_index;
|
|
}
|
|
};
|
|
|
|
using FieldReader = baseband::FieldReader<std::bitset<1024>, BitRemap>;
|
|
using CRCFieldReader = baseband::FieldReader<std::bitset<1024>, CRCBitRemap>;
|
|
|
|
struct PacketLengthRange {
|
|
constexpr PacketLengthRange(
|
|
) : min_bytes { 0 },
|
|
max_bytes { 0 }
|
|
{
|
|
}
|
|
|
|
constexpr PacketLengthRange(
|
|
const uint16_t min_bits,
|
|
const uint16_t max_bits
|
|
) : min_bytes { static_cast<uint8_t>(min_bits / 8U) },
|
|
max_bytes { static_cast<uint8_t>(max_bits / 8U) }
|
|
{
|
|
// static_assert((min_bits & 7) == 0, "minimum bits not a multiple of 8");
|
|
// static_assert((max_bits & 7) == 0, "minimum bits not a multiple of 8");
|
|
}
|
|
|
|
bool contains(const size_t bit_count) const {
|
|
return !is_above(bit_count) && !is_below(bit_count);
|
|
}
|
|
|
|
bool is_above(const size_t bit_count) const {
|
|
return (min() > bit_count);
|
|
}
|
|
|
|
bool is_below(const size_t bit_count) const {
|
|
return (max() < bit_count);
|
|
}
|
|
|
|
size_t min() const {
|
|
return min_bytes * 8;
|
|
}
|
|
|
|
size_t max() const {
|
|
return max_bytes * 8;
|
|
}
|
|
|
|
private:
|
|
const uint8_t min_bytes;
|
|
const uint8_t max_bytes;
|
|
};
|
|
|
|
constexpr std::array<PacketLengthRange, 64> packet_length_range { {
|
|
{ 0, 0 }, // 0
|
|
{ 168, 168 }, // 1
|
|
{ 168, 168 }, // 2
|
|
{ 168, 168 }, // 3
|
|
{ 168, 168 }, // 4
|
|
{ 424, 424 }, // 5
|
|
{ 0, 0 }, // 6
|
|
{ 0, 0 }, // 7
|
|
{ 0, 1008 }, // 8
|
|
{ 0, 0 }, // 9
|
|
{ 0, 0 }, // 10
|
|
{ 0, 0 }, // 11
|
|
{ 0, 0 }, // 12
|
|
{ 0, 0 }, // 13
|
|
{ 0, 0 }, // 14
|
|
{ 0, 0 }, // 15
|
|
{ 0, 0 }, // 16
|
|
{ 0, 0 }, // 17
|
|
{ 168, 168 }, // 18
|
|
{ 0, 0 }, // 19
|
|
{ 72, 160 }, // 20
|
|
{ 272, 360 }, // 21
|
|
{ 168, 168 }, // 22
|
|
{ 160, 160 }, // 23
|
|
{ 160, 168 }, // 24
|
|
{ 0, 168 }, // 25
|
|
{ 0, 0 }, // 26
|
|
{ 0, 0 }, // 27
|
|
{ 0, 0 }, // 28
|
|
{ 0, 0 }, // 29
|
|
{ 0, 0 }, // 30
|
|
{ 0, 0 }, // 31
|
|
} };
|
|
|
|
struct PacketLengthValidator {
|
|
bool operator()(const uint_fast8_t message_id, const size_t length) {
|
|
return packet_length_range[message_id].contains(length);
|
|
}
|
|
};
|
|
|
|
struct PacketTooLong {
|
|
bool operator()(const uint_fast8_t message_id, const size_t length) {
|
|
return packet_length_range[message_id].is_below(length);
|
|
}
|
|
};
|
|
|
|
struct CRCCheck {
|
|
bool operator()(const std::bitset<1024>& payload, const size_t data_length) {
|
|
CRCFieldReader field_crc { payload };
|
|
CRC<uint16_t> ais_fcs { 0x1021 };
|
|
|
|
uint16_t crc_calculated = 0xffff;
|
|
|
|
for(size_t i=0; i<data_length + 16; i+=8) {
|
|
if( i == data_length ) {
|
|
crc_calculated ^= 0xffff;
|
|
}
|
|
const uint8_t byte = field_crc.read(i, 8);
|
|
crc_calculated = ais_fcs.calculate_byte(crc_calculated, byte);
|
|
}
|
|
|
|
return crc_calculated == 0x0000;
|
|
}
|
|
};
|
|
|
|
} /* namespace ais */
|
|
} /* namespace baseband */
|
|
|
|
#endif/*__AIS_BASEBAND_H__*/
|