/* * 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 __AIS_BASEBAND_H__ #define __AIS_BASEBAND_H__ #include #include #include #include #include #include namespace baseband { namespace ais { // RRC length should be about 4 x the symbol length (4T) to do a good job of // cleaning up ISI. // Translate+RRC filter // sample=76.8k, deviation=2400, b=0.5, symbol=9600 // Length: 32 taps, 4 symbols, 1 cycle of sinusoid constexpr std::array, 32> rrc_taps_76k8_4t_p { { { 5.3368736990e-03f, 0.0000000000e+00f }, { 4.6850211151e-03f, 9.3190864122e-04f }, { 1.7970187432e-03f, 7.4434953528e-04f }, { -2.5478608559e-03f, -1.7024261963e-03f }, { -6.6710920858e-03f, -6.6710920858e-03f }, { -8.6960320791e-03f, -1.3014531722e-02f }, { -7.5474785839e-03f, -1.8221225159e-02f }, { -3.8115552023e-03f, -1.9161981995e-02f }, { -8.1697309033e-19f, -1.3342183083e-02f }, { 3.6940784220e-05f, -1.8571386338e-04f }, { -7.5474785839e-03f, 1.8221225159e-02f }, { -2.4954265902e-02f, 3.7346698152e-02f }, { -5.1450054092e-02f, 5.1450054092e-02f }, { -8.3018814119e-02f, 5.5471398140e-02f }, { -1.1321218147e-01f, 4.6894020990e-02f }, { -1.3498960022e-01f, 2.6851100952e-02f }, { -1.4292666316e-01f, 1.7503468055e-17f }, { -1.3498960022e-01f, -2.6851100952e-02f }, { -1.1321218147e-01f, -4.6894020990e-02f }, { -8.3018814119e-02f, -5.5471398140e-02f }, { -5.1450054092e-02f, -5.1450054092e-02f }, { -2.4954265902e-02f, -3.7346698152e-02f }, { -7.5474785839e-03f, -1.8221225159e-02f }, { 3.6940784220e-05f, 1.8571386338e-04f }, { 2.4509192710e-18f, 1.3342183083e-02f }, { -3.8115552023e-03f, 1.9161981995e-02f }, { -7.5474785839e-03f, 1.8221225159e-02f }, { -8.6960320791e-03f, 1.3014531722e-02f }, { -6.6710920858e-03f, 6.6710920858e-03f }, { -2.5478608559e-03f, 1.7024261963e-03f }, { 1.7970187432e-03f, -7.4434953528e-04f }, { 4.6850211151e-03f, -9.3190864122e-04f }, } }; using decoded_packet = std::pair; decoded_packet packet_decode(const std::bitset<1024>& data, const size_t data_length); } /* namespace ais */ } /* namespace baseband */ #endif/*__AIS_BASEBAND_H__*/