mirror of
https://github.com/portapack-mayhem/mayhem-firmware.git
synced 2024-12-14 04:04:34 +00:00
77 lines
1.8 KiB
C++
77 lines
1.8 KiB
C++
/*
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* Copyright (C) 2014 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 __DSP_DEMODULATE_H__
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#define __DSP_DEMODULATE_H__
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#include "dsp_types.hpp"
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namespace dsp {
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namespace demodulate {
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class AM {
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public:
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buffer_s16_t execute(
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buffer_c16_t src,
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buffer_s16_t dst
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);
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};
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class FM {
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public:
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constexpr FM(
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) : z_ { 0 },
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k { 0 }
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{
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}
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/*
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* angle: -pi to pi. output range: -32768 to 32767.
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* Maximum delta-theta (output of atan2) at maximum deviation frequency:
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* delta_theta_max = 2 * pi * deviation / sampling_rate
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*/
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constexpr FM(
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const float sampling_rate,
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const float deviation_hz
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) : z_ { 0 },
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k { static_cast<float>(32767.0f / (2.0 * pi * deviation_hz / sampling_rate)) }
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{
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}
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buffer_s16_t execute(
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buffer_c16_t src,
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buffer_s16_t dst
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);
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void configure(const float sampling_rate, const float deviation_hz) {
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k = static_cast<float>(32767.0f / (2.0 * pi * deviation_hz / sampling_rate));
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}
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private:
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complex16_t::rep_type z_;
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float k;
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};
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} /* namespace demodulate */
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} /* namespace dsp */
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#endif/*__DSP_DEMODULATE_H__*/
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