mayhem-firmware/firmware/common/ais_baseband.hpp
2016-01-31 09:34:24 +01:00

56 lines
2.1 KiB
C++

/*
* 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 <cstdint>
#include <cstddef>
#include <complex>
#include <array>
#include <bitset>
#include <utility>
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=38.4k, deviation=2400, b=0.5, symbol=9600
// Length: 16 taps, 4 symbols, 1 cycles of sinusoid
constexpr std::array<std::complex<float>, 16> rrc_taps_38k4_4t_p { {
{ 1.0619794019e-02f, 0.0000000000e+00f }, { 3.5758705854e-03f, 1.4811740938e-03f },
{ -1.3274742629e-02f, -1.3274742629e-02f }, { -1.5018657262e-02f, -3.6258246051e-02f },
{ 0.0000000000e+00f, -2.6549484581e-02f }, { -1.5018657262e-02f, 3.6258246051e-02f },
{ -1.0237997393e-01f, 1.0237997393e-01f }, { -2.2527985355e-01f, 9.3313970669e-02f },
{ -2.8440842032e-01f, 0.0000000000e+00f }, { -2.2527985355e-01f, -9.3313970669e-02f },
{ -1.0237997393e-01f, -1.0237997393e-01f }, { -1.5018657262e-02f, -3.6258246051e-02f },
{ 0.0000000000e+00f, 2.6549484581e-02f }, { -1.5018657262e-02f, 3.6258246051e-02f },
{ -1.3274742629e-02f, 1.3274742629e-02f }, { 3.5758705854e-03f, -1.4811740938e-03f },
} };
} /* namespace ais */
} /* namespace baseband */
#endif/*__AIS_BASEBAND_H__*/