/* * 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. */ #include "proc_ert.hpp" #include "portapack_shared_memory.hpp" float ERTProcessor::abs(const complex8_t& v) { // const int16_t r = v.real() - offset_i; // const int16_t i = v.imag() - offset_q; // const uint32_t r2 = r * r; // const uint32_t i2 = i * i; // const uint32_t r2_i2 = r2 + i2; // return std::sqrt(static_cast<float>(r2_i2)); const float r = static_cast<float>(v.real()) - offset_i; const float i = static_cast<float>(v.imag()) - offset_q; const float r2 = r * r; const float i2 = i * i; const float r2_i2 = r2 + i2; return std::sqrt(r2_i2); } void ERTProcessor::execute(const buffer_c8_t& buffer) { /* 4.194304MHz, 2048 samples */ const complex8_t* src = &buffer.p[0]; const complex8_t* const src_end = &buffer.p[buffer.count]; average_i += src->real(); average_q += src->imag(); average_count++; if( average_count == average_window ) { offset_i = static_cast<float>(average_i) / average_window; offset_q = static_cast<float>(average_q) / average_window; average_i = 0; average_q = 0; average_count = 0; } const float gain = 128 * samples_per_symbol; const float k = 1.0f / gain; while(src < src_end) { float sum = 0.0f; for(size_t i=0; i<(samples_per_symbol / 2); i++) { sum += abs(*(src++)); } sum_half_period[1] = sum_half_period[0]; sum_half_period[0] = sum; sum_period[2] = sum_period[1]; sum_period[1] = sum_period[0]; sum_period[0] = (sum_half_period[0] + sum_half_period[1]) * k; manchester[2] = manchester[1]; manchester[1] = manchester[0]; manchester[0] = sum_period[2] - sum_period[0]; const auto data = manchester[0] - manchester[2]; clock_recovery(data); } } void ERTProcessor::consume_symbol( const float raw_symbol ) { const uint_fast8_t sliced_symbol = (raw_symbol >= 0.0f) ? 1 : 0; scm_builder.execute(sliced_symbol); idm_builder.execute(sliced_symbol); } void ERTProcessor::scm_handler( const baseband::Packet& packet ) { const ERTPacketMessage message { ert::Packet::Type::SCM, packet }; shared_memory.application_queue.push(message); } void ERTProcessor::idm_handler( const baseband::Packet& packet ) { const ERTPacketMessage message { ert::Packet::Type::IDM, packet }; shared_memory.application_queue.push(message); }