mirror of
https://github.com/gnss-sdr/gnss-sdr
synced 2026-04-18 04:41:26 +00:00
GLONASS L2 CA Signal Addition
Adds GLONASS L2 C/A signal processing to GNSS-SDR based on previous work developed for the L1 signal. All code have been added in a single commit with the idea to illustrate the process of signal addition for future work
This commit is contained in:
Damian Miralles
@@ -24,7 +24,8 @@ set(TELEMETRY_DECODER_ADAPTER_SOURCES
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galileo_e1b_telemetry_decoder.cc
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sbas_l1_telemetry_decoder.cc
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galileo_e5a_telemetry_decoder.cc
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glonass_l1_ca_telemetry_decoder.cc
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glonass_l1_ca_telemetry_decoder.cc
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glonass_l2_ca_telemetry_decoder.cc
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)
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include_directories(
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@@ -0,0 +1,103 @@
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/*!
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* \file glonass_l2_ca_telemetry_decoder.cc
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* \brief Implementation of an adapter of a GLONASS L2 C/A NAV data decoder block
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* to a TelemetryDecoderInterface
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* \author Damian Miralles, 2018. dmiralles2009(at)gmail.com
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*
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* -------------------------------------------------------------------------
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*
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* Copyright (C) 2010-2015 (see AUTHORS file for a list of contributors)
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*
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* GNSS-SDR is a software defined Global Navigation
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* Satellite Systems receiver
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*
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* This file is part of GNSS-SDR.
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*
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* GNSS-SDR 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 3 of the License, or
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* (at your option) any later version.
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*
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* GNSS-SDR 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 GNSS-SDR. If not, see <http://www.gnu.org/licenses/>.
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*
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* -------------------------------------------------------------------------
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*/
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#include "glonass_l2_ca_telemetry_decoder.h"
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#include "configuration_interface.h"
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#include "glonass_gnav_ephemeris.h"
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#include "glonass_gnav_almanac.h"
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#include "glonass_gnav_utc_model.h"
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#include <gnuradio/io_signature.h>
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#include <glog/logging.h>
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using google::LogMessage;
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GlonassL2CaTelemetryDecoder::GlonassL2CaTelemetryDecoder(ConfigurationInterface* configuration,
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std::string role,
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unsigned int in_streams,
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unsigned int out_streams) : role_(role),
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in_streams_(in_streams),
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out_streams_(out_streams)
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{
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std::string default_dump_filename = "./navigation.dat";
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DLOG(INFO) << "role " << role;
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dump_ = configuration->property(role + ".dump", false);
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dump_filename_ = configuration->property(role + ".dump_filename", default_dump_filename);
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// make telemetry decoder object
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telemetry_decoder_ = glonass_l2_ca_make_telemetry_decoder_cc(satellite_, dump_);
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DLOG(INFO) << "telemetry_decoder(" << telemetry_decoder_->unique_id() << ")";
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channel_ = 0;
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}
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GlonassL2CaTelemetryDecoder::~GlonassL2CaTelemetryDecoder()
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{
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}
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void GlonassL2CaTelemetryDecoder::set_satellite(const Gnss_Satellite& satellite)
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{
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satellite_ = Gnss_Satellite(satellite.get_system(), satellite.get_PRN());
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telemetry_decoder_->set_satellite(satellite_);
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DLOG(INFO) << "TELEMETRY DECODER: satellite set to " << satellite_;
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}
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void GlonassL2CaTelemetryDecoder::connect(gr::top_block_sptr top_block)
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{
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if (top_block)
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{ /* top_block is not null */
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};
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// Nothing to connect internally
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DLOG(INFO) << "nothing to connect internally";
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}
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void GlonassL2CaTelemetryDecoder::disconnect(gr::top_block_sptr top_block)
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{
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if (top_block)
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{ /* top_block is not null */
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};
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// Nothing to disconnect
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}
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gr::basic_block_sptr GlonassL2CaTelemetryDecoder::get_left_block()
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{
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return telemetry_decoder_;
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}
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gr::basic_block_sptr GlonassL2CaTelemetryDecoder::get_right_block()
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{
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return telemetry_decoder_;
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}
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@@ -0,0 +1,90 @@
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/*!
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* \file glonass_l2_ca_telemetry_decoder.h
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* \brief Interface of an adapter of a GLONASS L2 C/A NAV data decoder block
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* to a TelemetryDecoderInterface
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* \author Damian Miralles, 2018. dmiralles2009(at)gmail.com
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*
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* -------------------------------------------------------------------------
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*
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* Copyright (C) 2010-2015 (see AUTHORS file for a list of contributors)
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*
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* GNSS-SDR is a software defined Global Navigation
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* Satellite Systems receiver
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*
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* This file is part of GNSS-SDR.
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*
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* GNSS-SDR 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 3 of the License, or
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* (at your option) any later version.
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*
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* GNSS-SDR 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 GNSS-SDR. If not, see <http://www.gnu.org/licenses/>.
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*
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* -------------------------------------------------------------------------
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*/
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#ifndef GNSS_SDR_GLONASS_L2_CA_TELEMETRY_DECODER_H_
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#define GNSS_SDR_GLONASS_L2_CA_TELEMETRY_DECODER_H_
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#include "telemetry_decoder_interface.h"
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#include "glonass_l2_ca_telemetry_decoder_cc.h"
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#include <string>
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class ConfigurationInterface;
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/*!
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* \brief This class implements a NAV data decoder for GLONASS L2 C/A
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*/
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class GlonassL2CaTelemetryDecoder : public TelemetryDecoderInterface
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{
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public:
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GlonassL2CaTelemetryDecoder(ConfigurationInterface* configuration,
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std::string role,
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unsigned int in_streams,
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unsigned int out_streams);
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virtual ~GlonassL2CaTelemetryDecoder();
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std::string role() override
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{
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return role_;
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}
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//! Returns "GLONASS_L2_CA_Telemetry_Decoder"
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std::string implementation() override
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{
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return "GLONASS_L2_CA_Telemetry_Decoder";
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}
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void connect(gr::top_block_sptr top_block) override;
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void disconnect(gr::top_block_sptr top_block) override;
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gr::basic_block_sptr get_left_block() override;
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gr::basic_block_sptr get_right_block() override;
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void set_satellite(const Gnss_Satellite& satellite) override;
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void set_channel(int channel) override { telemetry_decoder_->set_channel(channel); }
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void reset() override
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{
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return;
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}
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size_t item_size() override
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{
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return 0;
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}
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private:
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glonass_l2_ca_telemetry_decoder_cc_sptr telemetry_decoder_;
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Gnss_Satellite satellite_;
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int channel_;
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bool dump_;
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std::string dump_filename_;
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std::string role_;
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unsigned int in_streams_;
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unsigned int out_streams_;
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};
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#endif
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@@ -24,6 +24,7 @@ set(TELEMETRY_DECODER_GR_BLOCKS_SOURCES
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sbas_l1_telemetry_decoder_cc.cc
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galileo_e5a_telemetry_decoder_cc.cc
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glonass_l1_ca_telemetry_decoder_cc.cc
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glonass_l2_ca_telemetry_decoder_cc.cc
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)
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include_directories(
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@@ -34,7 +34,6 @@
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#define GNSS_SDR_GLONASS_L1_CA_TELEMETRY_DECODER_CC_H
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#include "GLONASS_L1_CA.h"
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#include "glonass_gnav_navigation_message.h"
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#include "glonass_gnav_ephemeris.h"
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#include "glonass_gnav_almanac.h"
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@@ -44,6 +43,7 @@
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#include <gnuradio/block.h>
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#include <fstream>
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#include <string>
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#include "../../../core/system_parameters/GLONASS_L1_L2_CA.h"
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class glonass_l1_ca_telemetry_decoder_cc;
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@@ -0,0 +1,449 @@
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/*!
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* \file glonass_l2_ca_telemetry_decoder_cc.cc
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* \brief Implementation of an adapter of a GLONASS L1 C/A NAV data decoder block
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* to a TelemetryDecoderInterface
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* \author Damian Miralles, 2018. dmiralles2009(at)gmail.com
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*
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* -------------------------------------------------------------------------
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*
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* Copyright (C) 2010-2015 (see AUTHORS file for a list of contributors)
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*
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* GNSS-SDR is a software defined Global Navigation
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* Satellite Systems receiver
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*
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* This file is part of GNSS-SDR.
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*
|
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* GNSS-SDR 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 3 of the License, or
|
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* (at your option) any later version.
|
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*
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* GNSS-SDR 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 GNSS-SDR. If not, see <http://www.gnu.org/licenses/>.
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*
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* -------------------------------------------------------------------------
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*/
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#include "glonass_l2_ca_telemetry_decoder_cc.h"
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#include <boost/lexical_cast.hpp>
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#include <gnuradio/io_signature.h>
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#include <glog/logging.h>
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#define CRC_ERROR_LIMIT 6
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using google::LogMessage;
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glonass_l2_ca_telemetry_decoder_cc_sptr
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glonass_l2_ca_make_telemetry_decoder_cc(const Gnss_Satellite &satellite, bool dump)
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{
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return glonass_l2_ca_telemetry_decoder_cc_sptr(new glonass_l2_ca_telemetry_decoder_cc(satellite, dump));
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}
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glonass_l2_ca_telemetry_decoder_cc::glonass_l2_ca_telemetry_decoder_cc(
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const Gnss_Satellite &satellite,
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bool dump) : gr::block("glonass_l2_ca_telemetry_decoder_cc", gr::io_signature::make(1, 1, sizeof(Gnss_Synchro)),
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gr::io_signature::make(1, 1, sizeof(Gnss_Synchro)))
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{
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// Telemetry Bit transition synchronization port out
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this->message_port_register_out(pmt::mp("preamble_timestamp_s"));
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// Ephemeris data port out
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this->message_port_register_out(pmt::mp("telemetry"));
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// initialize internal vars
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d_dump = dump;
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d_satellite = Gnss_Satellite(satellite.get_system(), satellite.get_PRN());
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LOG(INFO) << "Initializing GLONASS L2 CA TELEMETRY DECODING";
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// Define the number of sampes per symbol. Notice that GLONASS has 2 rates,
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//one for the navigation data and the other for the preamble information
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d_samples_per_symbol = (GLONASS_L2_CA_CODE_RATE_HZ / GLONASS_L2_CA_CODE_LENGTH_CHIPS) / GLONASS_L2_CA_SYMBOL_RATE_BPS;
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// Set the preamble information
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unsigned short int preambles_bits[GLONASS_GNAV_PREAMBLE_LENGTH_BITS] = GLONASS_GNAV_PREAMBLE;
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// Since preamble rate is different than navigation data rate we use a constant
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d_symbols_per_preamble = GLONASS_GNAV_PREAMBLE_LENGTH_SYMBOLS;
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memcpy(static_cast<unsigned short int *>(this->d_preambles_bits), static_cast<unsigned short int *>(preambles_bits), GLONASS_GNAV_PREAMBLE_LENGTH_BITS * sizeof(unsigned short int));
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// preamble bits to sampled symbols
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d_preambles_symbols = static_cast<signed int *>(malloc(sizeof(signed int) * d_symbols_per_preamble));
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int n = 0;
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for (int i = 0; i < GLONASS_GNAV_PREAMBLE_LENGTH_BITS; i++)
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{
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for (unsigned int j = 0; j < GLONASS_GNAV_TELEMETRY_SYMBOLS_PER_PREAMBLE_BIT; j++)
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{
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if (d_preambles_bits[i] == 1)
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{
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d_preambles_symbols[n] = 1;
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}
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else
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{
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d_preambles_symbols[n] = -1;
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}
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n++;
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}
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}
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d_sample_counter = 0;
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d_stat = 0;
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d_preamble_index = 0;
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d_flag_frame_sync = false;
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d_flag_parity = false;
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d_TOW_at_current_symbol = 0;
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Flag_valid_word = false;
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delta_t = 0;
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d_CRC_error_counter = 0;
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d_flag_preamble = false;
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d_channel = 0;
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flag_TOW_set = false;
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d_preamble_time_samples = 0;
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}
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glonass_l2_ca_telemetry_decoder_cc::~glonass_l2_ca_telemetry_decoder_cc()
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{
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delete d_preambles_symbols;
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if (d_dump_file.is_open() == true)
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{
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try
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{
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d_dump_file.close();
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}
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catch (const std::exception &ex)
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{
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LOG(WARNING) << "Exception in destructor closing the dump file " << ex.what();
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}
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}
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}
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void glonass_l2_ca_telemetry_decoder_cc::decode_string(double *frame_symbols, int frame_length)
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{
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double chip_acc = 0.0;
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int chip_acc_counter = 0;
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// 1. Transform from symbols to bits
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std::string bi_binary_code;
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std::string relative_code;
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std::string data_bits;
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// Group samples into bi-binary code
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for (int i = 0; i < (frame_length); i++)
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{
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chip_acc += frame_symbols[i];
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chip_acc_counter += 1;
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if (chip_acc_counter == (GLONASS_GNAV_TELEMETRY_SYMBOLS_PER_BIT))
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{
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if (chip_acc > 0)
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{
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bi_binary_code.push_back('1');
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chip_acc_counter = 0;
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chip_acc = 0;
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}
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else
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{
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bi_binary_code.push_back('0');
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chip_acc_counter = 0;
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chip_acc = 0;
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}
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}
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}
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// Convert from bi-binary code to relative code
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for (int i = 0; i < (GLONASS_GNAV_STRING_BITS); i++)
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{
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if (bi_binary_code[2 * i] == '1' && bi_binary_code[2 * i + 1] == '0')
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{
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relative_code.push_back('1');
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}
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else
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{
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relative_code.push_back('0');
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}
|
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}
|
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// Convert from relative code to data bits
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data_bits.push_back('0');
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for (int i = 1; i < (GLONASS_GNAV_STRING_BITS); i++)
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{
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data_bits.push_back(((relative_code[i - 1] - '0') ^ (relative_code[i] - '0')) + '0');
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}
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// 2. Call the GLONASS GNAV string decoder
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d_nav.string_decoder(data_bits);
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|
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// 3. Check operation executed correctly
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if (d_nav.flag_CRC_test == true)
|
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{
|
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LOG(INFO) << "GLONASS GNAV CRC correct on channel " << d_channel << " from satellite " << d_satellite;
|
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}
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else
|
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{
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LOG(INFO) << "GLONASS GNAV CRC error on channel " << d_channel << " from satellite " << d_satellite;
|
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}
|
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// 4. Push the new navigation data to the queues
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if (d_nav.have_new_ephemeris() == true)
|
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{
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// get object for this SV (mandatory)
|
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d_nav.gnav_ephemeris.i_satellite_freq_channel = d_satellite.get_rf_link();
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std::shared_ptr<Glonass_Gnav_Ephemeris> tmp_obj = std::make_shared<Glonass_Gnav_Ephemeris>(d_nav.get_ephemeris());
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this->message_port_pub(pmt::mp("telemetry"), pmt::make_any(tmp_obj));
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LOG(INFO) << "GLONASS GNAV Ephemeris have been received on channel" << d_channel << " from satellite " << d_satellite;
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}
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if (d_nav.have_new_utc_model() == true)
|
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{
|
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// get object for this SV (mandatory)
|
||||
std::shared_ptr<Glonass_Gnav_Utc_Model> tmp_obj = std::make_shared<Glonass_Gnav_Utc_Model>(d_nav.get_utc_model());
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this->message_port_pub(pmt::mp("telemetry"), pmt::make_any(tmp_obj));
|
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LOG(INFO) << "GLONASS GNAV UTC Model have been received on channel" << d_channel << " from satellite " << d_satellite;
|
||||
}
|
||||
if (d_nav.have_new_almanac() == true)
|
||||
{
|
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unsigned int slot_nbr = d_nav.i_alm_satellite_slot_number;
|
||||
std::shared_ptr<Glonass_Gnav_Almanac> tmp_obj = std::make_shared<Glonass_Gnav_Almanac>(d_nav.get_almanac(slot_nbr));
|
||||
this->message_port_pub(pmt::mp("telemetry"), pmt::make_any(tmp_obj));
|
||||
LOG(INFO) << "GLONASS GNAV Almanac have been received on channel" << d_channel << " in slot number " << slot_nbr;
|
||||
}
|
||||
// 5. Update satellite information on system
|
||||
if (d_nav.flag_update_slot_number == true)
|
||||
{
|
||||
LOG(INFO) << "GLONASS GNAV Slot Number Identified on channel " << d_channel;
|
||||
d_satellite.update_PRN(d_nav.gnav_ephemeris.d_n);
|
||||
d_satellite.what_block(d_satellite.get_system(), d_nav.gnav_ephemeris.d_n);
|
||||
d_nav.flag_update_slot_number = false;
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
int glonass_l2_ca_telemetry_decoder_cc::general_work(int noutput_items __attribute__((unused)), gr_vector_int &ninput_items __attribute__((unused)),
|
||||
gr_vector_const_void_star &input_items, gr_vector_void_star &output_items)
|
||||
{
|
||||
int corr_value = 0;
|
||||
int preamble_diff = 0;
|
||||
|
||||
Gnss_Synchro **out = reinterpret_cast<Gnss_Synchro **>(&output_items[0]); // Get the output buffer pointer
|
||||
const Gnss_Synchro **in = reinterpret_cast<const Gnss_Synchro **>(&input_items[0]); // Get the input buffer pointer
|
||||
|
||||
Gnss_Synchro current_symbol; //structure to save the synchronization information and send the output object to the next block
|
||||
//1. Copy the current tracking output
|
||||
current_symbol = in[0][0];
|
||||
d_symbol_history.push_back(current_symbol); //add new symbol to the symbol queue
|
||||
d_sample_counter++; //count for the processed samples
|
||||
consume_each(1);
|
||||
|
||||
d_flag_preamble = false;
|
||||
unsigned int required_symbols = GLONASS_GNAV_STRING_SYMBOLS;
|
||||
|
||||
if (d_symbol_history.size() > required_symbols)
|
||||
{
|
||||
//******* preamble correlation ********
|
||||
for (int i = 0; i < d_symbols_per_preamble; i++)
|
||||
{
|
||||
if (d_symbol_history.at(i).Prompt_I < 0) // symbols clipping
|
||||
{
|
||||
corr_value -= d_preambles_symbols[i];
|
||||
}
|
||||
else
|
||||
{
|
||||
corr_value += d_preambles_symbols[i];
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
//******* frame sync ******************
|
||||
if (d_stat == 0) //no preamble information
|
||||
{
|
||||
if (abs(corr_value) >= d_symbols_per_preamble)
|
||||
{
|
||||
// Record the preamble sample stamp
|
||||
d_preamble_index = d_sample_counter;
|
||||
LOG(INFO) << "Preamble detection for GLONASS L2 C/A SAT " << this->d_satellite;
|
||||
// Enter into frame pre-detection status
|
||||
d_stat = 1;
|
||||
d_preamble_time_samples = d_symbol_history.at(0).Tracking_sample_counter; // record the preamble sample stamp
|
||||
}
|
||||
}
|
||||
else if (d_stat == 1) // posible preamble lock
|
||||
{
|
||||
if (abs(corr_value) >= d_symbols_per_preamble)
|
||||
{
|
||||
//check preamble separation
|
||||
preamble_diff = d_sample_counter - d_preamble_index;
|
||||
// Record the PRN start sample index associated to the preamble
|
||||
d_preamble_time_samples = d_symbol_history.at(0).Tracking_sample_counter;
|
||||
if (abs(preamble_diff - GLONASS_GNAV_PREAMBLE_PERIOD_SYMBOLS) == 0)
|
||||
{
|
||||
//try to decode frame
|
||||
LOG(INFO) << "Starting string decoder for GLONASS L2 C/A SAT " << this->d_satellite;
|
||||
d_preamble_index = d_sample_counter; //record the preamble sample stamp
|
||||
d_stat = 2;
|
||||
// send asynchronous message to tracking to inform of frame sync and extend correlation time
|
||||
pmt::pmt_t value = pmt::from_double(static_cast<double>(d_preamble_time_samples) / static_cast<double>(d_symbol_history.at(0).fs) - 0.001);
|
||||
this->message_port_pub(pmt::mp("preamble_timestamp_s"), value);
|
||||
}
|
||||
else
|
||||
{
|
||||
if (preamble_diff > GLONASS_GNAV_PREAMBLE_PERIOD_SYMBOLS)
|
||||
{
|
||||
d_stat = 0; // start again
|
||||
}
|
||||
DLOG(INFO) << "Failed string decoder for GLONASS L2 C/A SAT " << this->d_satellite;
|
||||
}
|
||||
}
|
||||
}
|
||||
else if (d_stat == 2)
|
||||
{
|
||||
// FIXME: The preamble index marks the first symbol of the string count. Here I just wait for another full string to be received before processing
|
||||
if (d_sample_counter == d_preamble_index + GLONASS_GNAV_STRING_SYMBOLS)
|
||||
{
|
||||
// NEW GLONASS string received
|
||||
// 0. fetch the symbols into an array
|
||||
int string_length = GLONASS_GNAV_STRING_SYMBOLS - d_symbols_per_preamble;
|
||||
double string_symbols[GLONASS_GNAV_DATA_SYMBOLS] = {0};
|
||||
|
||||
//******* SYMBOL TO BIT *******
|
||||
for (int i = 0; i < string_length; i++)
|
||||
{
|
||||
if (corr_value > 0)
|
||||
{
|
||||
string_symbols[i] = d_symbol_history.at(i + d_symbols_per_preamble).Prompt_I; // because last symbol of the preamble is just received now!
|
||||
}
|
||||
else
|
||||
{
|
||||
string_symbols[i] = -d_symbol_history.at(i + d_symbols_per_preamble).Prompt_I; // because last symbol of the preamble is just received now!
|
||||
}
|
||||
}
|
||||
|
||||
//call the decoder
|
||||
decode_string(string_symbols, string_length);
|
||||
if (d_nav.flag_CRC_test == true)
|
||||
{
|
||||
d_CRC_error_counter = 0;
|
||||
d_flag_preamble = true; //valid preamble indicator (initialized to false every work())
|
||||
d_preamble_index = d_sample_counter; //record the preamble sample stamp (t_P)
|
||||
if (!d_flag_frame_sync)
|
||||
{
|
||||
d_flag_frame_sync = true;
|
||||
DLOG(INFO) << " Frame sync SAT " << this->d_satellite << " with preamble start at "
|
||||
<< d_symbol_history.at(0).Tracking_sample_counter << " [samples]";
|
||||
}
|
||||
}
|
||||
else
|
||||
{
|
||||
d_CRC_error_counter++;
|
||||
d_preamble_index = d_sample_counter; //record the preamble sample stamp
|
||||
if (d_CRC_error_counter > CRC_ERROR_LIMIT)
|
||||
{
|
||||
LOG(INFO) << "Lost of frame sync SAT " << this->d_satellite;
|
||||
d_flag_frame_sync = false;
|
||||
d_stat = 0;
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// UPDATE GNSS SYNCHRO DATA
|
||||
//2. Add the telemetry decoder information
|
||||
if (this->d_flag_preamble == true and d_nav.flag_TOW_new == true)
|
||||
//update TOW at the preamble instant
|
||||
{
|
||||
d_TOW_at_current_symbol = floor((d_nav.gnav_ephemeris.d_TOW - GLONASS_GNAV_PREAMBLE_DURATION_S) * 1000) / 1000;
|
||||
d_nav.flag_TOW_new = false;
|
||||
}
|
||||
else //if there is not a new preamble, we define the TOW of the current symbol
|
||||
{
|
||||
d_TOW_at_current_symbol = d_TOW_at_current_symbol + GLONASS_L2_CA_CODE_PERIOD;
|
||||
}
|
||||
|
||||
//if (d_flag_frame_sync == true and d_nav.flag_TOW_set==true and d_nav.flag_CRC_test == true)
|
||||
|
||||
// if(d_nav.flag_GGTO_1 == true and d_nav.flag_GGTO_2 == true and d_nav.flag_GGTO_3 == true and d_nav.flag_GGTO_4 == true) //all GGTO parameters arrived
|
||||
// {
|
||||
// delta_t = d_nav.A_0G_10 + d_nav.A_1G_10 * (d_TOW_at_current_symbol - d_nav.t_0G_10 + 604800.0 * (fmod((d_nav.WN_0 - d_nav.WN_0G_10), 64)));
|
||||
// }
|
||||
|
||||
if (d_flag_frame_sync == true and d_nav.flag_TOW_set == true)
|
||||
{
|
||||
current_symbol.Flag_valid_word = true;
|
||||
}
|
||||
else
|
||||
{
|
||||
current_symbol.Flag_valid_word = false;
|
||||
}
|
||||
|
||||
current_symbol.PRN = this->d_satellite.get_PRN();
|
||||
current_symbol.TOW_at_current_symbol_s = d_TOW_at_current_symbol;
|
||||
current_symbol.TOW_at_current_symbol_s -= delta_t; // Galileo to GPS TOW
|
||||
|
||||
if (d_dump == true)
|
||||
{
|
||||
// MULTIPLEXED FILE RECORDING - Record results to file
|
||||
try
|
||||
{
|
||||
double tmp_double;
|
||||
unsigned long int tmp_ulong_int;
|
||||
tmp_double = d_TOW_at_current_symbol;
|
||||
d_dump_file.write(reinterpret_cast<char *>(&tmp_double), sizeof(double));
|
||||
tmp_ulong_int = current_symbol.Tracking_sample_counter;
|
||||
d_dump_file.write(reinterpret_cast<char *>(&tmp_ulong_int), sizeof(unsigned long int));
|
||||
tmp_double = 0;
|
||||
d_dump_file.write(reinterpret_cast<char *>(&tmp_double), sizeof(double));
|
||||
}
|
||||
catch (const std::ifstream::failure &e)
|
||||
{
|
||||
LOG(WARNING) << "Exception writing observables dump file " << e.what();
|
||||
}
|
||||
}
|
||||
|
||||
// remove used symbols from history
|
||||
if (d_symbol_history.size() > required_symbols)
|
||||
{
|
||||
d_symbol_history.pop_front();
|
||||
}
|
||||
//3. Make the output (copy the object contents to the GNURadio reserved memory)
|
||||
*out[0] = current_symbol;
|
||||
|
||||
return 1;
|
||||
}
|
||||
|
||||
|
||||
void glonass_l2_ca_telemetry_decoder_cc::set_satellite(const Gnss_Satellite &satellite)
|
||||
{
|
||||
d_satellite = Gnss_Satellite(satellite.get_system(), satellite.get_PRN());
|
||||
DLOG(INFO) << "Setting decoder Finite State Machine to satellite " << d_satellite;
|
||||
DLOG(INFO) << "Navigation Satellite set to " << d_satellite;
|
||||
}
|
||||
|
||||
|
||||
void glonass_l2_ca_telemetry_decoder_cc::set_channel(int channel)
|
||||
{
|
||||
d_channel = channel;
|
||||
LOG(INFO) << "Navigation channel set to " << channel;
|
||||
// ############# ENABLE DATA FILE LOG #################
|
||||
if (d_dump == true)
|
||||
{
|
||||
if (d_dump_file.is_open() == false)
|
||||
{
|
||||
try
|
||||
{
|
||||
d_dump_filename = "telemetry";
|
||||
d_dump_filename.append(boost::lexical_cast<std::string>(d_channel));
|
||||
d_dump_filename.append(".dat");
|
||||
d_dump_file.exceptions(std::ifstream::failbit | std::ifstream::badbit);
|
||||
d_dump_file.open(d_dump_filename.c_str(), std::ios::out | std::ios::binary);
|
||||
LOG(INFO) << "Telemetry decoder dump enabled on channel " << d_channel << " Log file: " << d_dump_filename.c_str();
|
||||
}
|
||||
catch (const std::ifstream::failure &e)
|
||||
{
|
||||
LOG(WARNING) << "channel " << d_channel << ": exception opening Glonass TLM dump file. " << e.what();
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
@@ -0,0 +1,117 @@
|
||||
/*!
|
||||
* \file glonass_l2_ca_telemetry_decoder_cc.h
|
||||
* \brief Implementation of an adapter of a GLONASS L2 C/A NAV data decoder block
|
||||
* to a TelemetryDecoderInterface
|
||||
* \author Damian Miralles, 2018. dmiralles2009(at)gmail.com
|
||||
*
|
||||
* -------------------------------------------------------------------------
|
||||
*
|
||||
* Copyright (C) 2010-2015 (see AUTHORS file for a list of contributors)
|
||||
*
|
||||
* GNSS-SDR is a software defined Global Navigation
|
||||
* Satellite Systems receiver
|
||||
*
|
||||
* This file is part of GNSS-SDR.
|
||||
*
|
||||
* GNSS-SDR 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 3 of the License, or
|
||||
* (at your option) any later version.
|
||||
*
|
||||
* GNSS-SDR 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 GNSS-SDR. If not, see <http://www.gnu.org/licenses/>.
|
||||
*
|
||||
* -------------------------------------------------------------------------
|
||||
*/
|
||||
|
||||
#ifndef GNSS_SDR_GLONASS_L2_CA_TELEMETRY_DECODER_CC_H
|
||||
#define GNSS_SDR_GLONASS_L2_CA_TELEMETRY_DECODER_CC_H
|
||||
|
||||
|
||||
#include "GLONASS_L1_L2_CA.h"
|
||||
#include "glonass_gnav_navigation_message.h"
|
||||
#include "glonass_gnav_ephemeris.h"
|
||||
#include "glonass_gnav_almanac.h"
|
||||
#include "glonass_gnav_utc_model.h"
|
||||
#include "gnss_satellite.h"
|
||||
#include "gnss_synchro.h"
|
||||
#include <gnuradio/block.h>
|
||||
#include <fstream>
|
||||
#include <string>
|
||||
|
||||
|
||||
class glonass_l2_ca_telemetry_decoder_cc;
|
||||
|
||||
typedef boost::shared_ptr<glonass_l2_ca_telemetry_decoder_cc> glonass_l2_ca_telemetry_decoder_cc_sptr;
|
||||
|
||||
glonass_l2_ca_telemetry_decoder_cc_sptr glonass_l2_ca_make_telemetry_decoder_cc(const Gnss_Satellite &satellite, bool dump);
|
||||
|
||||
/*!
|
||||
* \brief This class implements a block that decodes the GNAV data defined in GLONASS ICD v5.1
|
||||
* \see <a href="http://russianspacesystems.ru/wp-content/uploads/2016/08/ICD_GLONASS_eng_v5.1.pdf">GLONASS ICD</a>
|
||||
*
|
||||
*/
|
||||
class glonass_l2_ca_telemetry_decoder_cc : public gr::block
|
||||
{
|
||||
public:
|
||||
~glonass_l2_ca_telemetry_decoder_cc(); //!< Class destructor
|
||||
void set_satellite(const Gnss_Satellite &satellite); //!< Set satellite PRN
|
||||
void set_channel(int channel); //!< Set receiver's channel
|
||||
|
||||
/*!
|
||||
* \brief This is where all signal processing takes place
|
||||
*/
|
||||
int general_work(int noutput_items, gr_vector_int &ninput_items,
|
||||
gr_vector_const_void_star &input_items, gr_vector_void_star &output_items);
|
||||
|
||||
private:
|
||||
friend glonass_l2_ca_telemetry_decoder_cc_sptr
|
||||
glonass_l2_ca_make_telemetry_decoder_cc(const Gnss_Satellite &satellite, bool dump);
|
||||
glonass_l2_ca_telemetry_decoder_cc(const Gnss_Satellite &satellite, bool dump);
|
||||
|
||||
void decode_string(double *symbols, int frame_length);
|
||||
|
||||
//!< Help with coherent tracking
|
||||
double d_preamble_time_samples;
|
||||
|
||||
//!< Preamble decoding
|
||||
unsigned short int d_preambles_bits[GLONASS_GNAV_PREAMBLE_LENGTH_BITS];
|
||||
int *d_preambles_symbols;
|
||||
unsigned int d_samples_per_symbol;
|
||||
int d_symbols_per_preamble;
|
||||
|
||||
//!< Storage for incoming data
|
||||
std::deque<Gnss_Synchro> d_symbol_history;
|
||||
|
||||
//!< Variables for internal functionality
|
||||
long unsigned int d_sample_counter; //!< Sample counter as an index (1,2,3,..etc) indicating number of samples processed
|
||||
long unsigned int d_preamble_index; //!< Index of sample number where preamble was found
|
||||
unsigned int d_stat; //!< Status of decoder
|
||||
bool d_flag_frame_sync; //!< Indicate when a frame sync is achieved
|
||||
bool d_flag_parity; //!< Flag indicating when parity check was achieved (crc check)
|
||||
bool d_flag_preamble; //!< Flag indicating when preamble was found
|
||||
int d_CRC_error_counter; //!< Number of failed CRC operations
|
||||
bool flag_TOW_set; //!< Indicates when time of week is set
|
||||
double delta_t; //!< GPS-GLONASS time offset
|
||||
|
||||
//!< Navigation Message variable
|
||||
Glonass_Gnav_Navigation_Message d_nav;
|
||||
|
||||
//!< Values to populate gnss synchronization structure
|
||||
double d_TOW_at_current_symbol;
|
||||
bool Flag_valid_word;
|
||||
|
||||
//!< Satellite Information and logging capacity
|
||||
Gnss_Satellite d_satellite;
|
||||
int d_channel;
|
||||
bool d_dump;
|
||||
std::string d_dump_filename;
|
||||
std::ofstream d_dump_file;
|
||||
};
|
||||
|
||||
#endif
|
||||
Reference in New Issue
Block a user