gnss-sdr/src/algorithms/tracking/adapters/gps_l1_ca_dll_pll_tracking.cc

/*!
 * \file gps_l1_ca_dll_pll_tracking.cc
 * \brief Implementation of an adapter of a DLL+PLL tracking loop block
 * for GPS L1 C/A to a TrackingInterface
 * \author Carlos Aviles, 2010. carlos.avilesr(at)googlemail.com
 *         Javier Arribas, 2011. jarribas(at)cttc.es
 *
 * Code DLL + carrier PLL according to the algorithms described in:
 * K.Borre, D.M.Akos, N.Bertelsen, P.Rinder, and S.H.Jensen,
 * A Software-Defined GPS and Galileo Receiver. A Single-Frequency
 * Approach, Birkhauser, 2007
 *
 * -----------------------------------------------------------------------------
 *
 * GNSS-SDR is a Global Navigation Satellite System software-defined receiver.
 * This file is part of GNSS-SDR.
 *
 * Copyright (C) 2010-2020  (see AUTHORS file for a list of contributors)
 * SPDX-License-Identifier: GPL-3.0-or-later
 *
 * -----------------------------------------------------------------------------
 */

#include "gps_l1_ca_dll_pll_tracking.h"
#include "GPS_L1_CA.h"
#include "configuration_interface.h"
#include "display.h"
#include "dll_pll_conf.h"
#include "gnss_sdr_flags.h"
#include <algorithm>
#include <array>

#if USE_GLOG_AND_GFLAGS
#include <glog/logging.h>
#else
#include <absl/log/log.h>
#endif

GpsL1CaDllPllTracking::GpsL1CaDllPllTracking(
    const ConfigurationInterface* configuration,
    const std::string& role,
    unsigned int in_streams, unsigned int out_streams)
    : role_(role),
      item_size_(sizeof(gr_complex)),
      channel_(0),
      in_streams_(in_streams),
      out_streams_(out_streams)
{
    Dll_Pll_Conf trk_params = Dll_Pll_Conf();
    trk_params.SetFromConfiguration(configuration, role_);

    const auto vector_length = static_cast<int>(std::round(trk_params.fs_in / (GPS_L1_CA_CODE_RATE_CPS / GPS_L1_CA_CODE_LENGTH_CHIPS)));
    trk_params.vector_length = vector_length;
    if (trk_params.extend_correlation_symbols < 1)
        {
            trk_params.extend_correlation_symbols = 1;
            std::cout << TEXT_RED << "WARNING: GPS L1 C/A. extend_correlation_symbols must be bigger than 1. Coherent integration has been set to 1 symbol (1 ms)" << TEXT_RESET << '\n';
        }
    else if (trk_params.extend_correlation_symbols > 20)
        {
            trk_params.extend_correlation_symbols = 20;
            std::cout << TEXT_RED << "WARNING: GPS L1 C/A. extend_correlation_symbols must be lower than 21. Coherent integration has been set to 20 symbols (20 ms)" << TEXT_RESET << '\n';
        }
    trk_params.track_pilot = configuration->property(role_ + ".track_pilot", false);
    if (trk_params.track_pilot)
        {
            trk_params.track_pilot = false;
            std::cout << TEXT_RED << "WARNING: GPS L1 C/A does not have pilot signal. Data tracking has been enabled" << TEXT_RESET << '\n';
        }
    if ((trk_params.extend_correlation_symbols > 1) and (trk_params.pll_bw_narrow_hz > trk_params.pll_bw_hz or trk_params.dll_bw_narrow_hz > trk_params.dll_bw_hz))
        {
            std::cout << TEXT_RED << "WARNING: GPS L1 C/A. PLL or DLL narrow tracking bandwidth is higher than wide tracking one" << TEXT_RESET << '\n';
        }

    trk_params.system = 'G';
    const std::array<char, 3> sig{'1', 'C', '\0'};
    std::copy_n(sig.data(), 3, trk_params.signal);

    // ################# Make a GNU Radio Tracking block object ################
    DLOG(INFO) << "role " << role_;
    if (trk_params.item_type == "gr_complex")
        {
            tracking_sptr_ = dll_pll_veml_make_tracking(trk_params);
            DLOG(INFO) << "tracking(" << tracking_sptr_->unique_id() << ")";
        }
    else
        {
            item_size_ = 0;
            tracking_sptr_ = nullptr;
            LOG(WARNING) << trk_params.item_type << " unknown tracking item type.";
        }

    if (in_streams_ > 1)
        {
            LOG(ERROR) << "This implementation only supports one input stream";
        }
    if (out_streams_ > 1)
        {
            LOG(ERROR) << "This implementation only supports one output stream";
        }
}


void GpsL1CaDllPllTracking::stop_tracking()
{
    tracking_sptr_->stop_tracking();
}


void GpsL1CaDllPllTracking::start_tracking()
{
    tracking_sptr_->start_tracking();
}


/*
 * Set tracking channel unique ID
 */
void GpsL1CaDllPllTracking::set_channel(unsigned int channel)
{
    channel_ = channel;
    tracking_sptr_->set_channel(channel);
}


void GpsL1CaDllPllTracking::set_gnss_synchro(Gnss_Synchro* p_gnss_synchro)
{
    tracking_sptr_->set_gnss_synchro(p_gnss_synchro);
}


void GpsL1CaDllPllTracking::connect(gr::top_block_sptr top_block)
{
    if (top_block)
        { /* top_block is not null */
        };
    // nothing to connect, now the tracking uses gr_sync_decimator
}


void GpsL1CaDllPllTracking::disconnect(gr::top_block_sptr top_block)
{
    if (top_block)
        { /* top_block is not null */
        };
    // nothing to disconnect, now the tracking uses gr_sync_decimator
}


gr::basic_block_sptr GpsL1CaDllPllTracking::get_left_block()
{
    return tracking_sptr_;
}


gr::basic_block_sptr GpsL1CaDllPllTracking::get_right_block()
{
    return tracking_sptr_;
}