/*! * \file gps_l5_dll_pll_tracking_fpga.cc * \brief Interface of an adapter of a DLL+PLL tracking loop block * for GPS L5 to a TrackingInterface for the FPGA * \author Marc Majoral, 2019. mmajoral(at)cttc.cat * Javier Arribas, 2019. 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_l5_dll_pll_tracking_fpga.h" #include "GPS_L5.h" #include "configuration_interface.h" #include "display.h" #include "dll_pll_conf_fpga.h" #include "gnss_sdr_flags.h" #include "gps_l5_signal_replica.h" #include "uio_fpga.h" #include #include #include #if USE_GLOG_AND_GFLAGS #include #else #include #endif GpsL5DllPllTrackingFpga::GpsL5DllPllTrackingFpga( const ConfigurationInterface *configuration, const std::string &role, unsigned int in_streams, unsigned int out_streams) : role_(role), data_codes_ptr_(nullptr), channel_(0), in_streams_(in_streams), out_streams_(out_streams) { Dll_Pll_Conf_Fpga trk_params_fpga = Dll_Pll_Conf_Fpga(); trk_params_fpga.SetFromConfiguration(configuration, role_); const auto vector_length = static_cast(std::round(static_cast(trk_params_fpga.fs_in) / (static_cast(GPS_L5I_CODE_RATE_CPS) / static_cast(GPS_L5I_CODE_LENGTH_CHIPS)))); trk_params_fpga.vector_length = vector_length; if (trk_params_fpga.extend_correlation_symbols < 1) { trk_params_fpga.extend_correlation_symbols = 1; std::cout << TEXT_RED << "WARNING: GPS L5. extend_correlation_symbols must be bigger than 0. Coherent integration has been set to 1 symbol (1 ms)" << TEXT_RESET << '\n'; } else if (!trk_params_fpga.track_pilot and trk_params_fpga.extend_correlation_symbols > GPS_L5I_NH_CODE_LENGTH) { trk_params_fpga.extend_correlation_symbols = GPS_L5I_NH_CODE_LENGTH; std::cout << TEXT_RED << "WARNING: GPS L5. extend_correlation_symbols must be lower than 11 when tracking the data component. Coherent integration has been set to 10 symbols (10 ms)" << TEXT_RESET << '\n'; } if ((trk_params_fpga.extend_correlation_symbols > 1) and (trk_params_fpga.pll_bw_narrow_hz > trk_params_fpga.pll_bw_hz or trk_params_fpga.dll_bw_narrow_hz > trk_params_fpga.dll_bw_hz)) { std::cout << TEXT_RED << "WARNING: GPS L5. PLL or DLL narrow tracking bandwidth is higher than wide tracking one" << TEXT_RESET << '\n'; } track_pilot_ = trk_params_fpga.track_pilot; trk_params_fpga.system = 'G'; const std::array sig{'L', '5', '\0'}; std::copy_n(sig.data(), 3, trk_params_fpga.signal); // UIO device file device_name_ = configuration->property(role_ + ".devicename", default_device_name_GPS_L5_); // compute the number of tracking channels that have already been instantiated. The order in which // GNSS-SDR instantiates the tracking channels i L1, L2, L5, E1, E5a uint32_t num_prev_assigned_ch_1C = configuration->property("Channels_1C.count", 0); uint32_t num_prev_assigned_ch_2S = 0; if (configuration->property("Tracking_2S.devicename", std::string("")) != device_name_) { num_prev_assigned_ch_2S = configuration->property("Channels_2S.count", 0); } num_prev_assigned_ch_ = num_prev_assigned_ch_1C + num_prev_assigned_ch_2S; // ################# PRE-COMPUTE ALL THE CODES ################# uint32_t code_samples_per_chip = 1; auto code_length_chips = static_cast(GPS_L5I_CODE_LENGTH_CHIPS); volk_gnsssdr::vector data_code; volk_gnsssdr::vector tracking_code(code_length_chips, 0.0); if (track_pilot_) { data_code.resize(code_length_chips, 0.0); } prn_codes_ptr_ = static_cast(volk_gnsssdr_malloc(static_cast(code_length_chips * NUM_PRNs) * sizeof(int32_t), volk_gnsssdr_get_alignment())); if (track_pilot_) { data_codes_ptr_ = static_cast(volk_gnsssdr_malloc((static_cast(code_length_chips)) * NUM_PRNs * sizeof(int32_t), volk_gnsssdr_get_alignment())); } for (uint32_t PRN = 1; PRN <= NUM_PRNs; PRN++) { if (track_pilot_) { gps_l5q_code_gen_float(tracking_code, PRN); gps_l5i_code_gen_float(data_code, PRN); // The code is generated as a series of 1s and -1s. In order to store the values using only one bit, a -1 is stored as a 0 in the FPGA for (uint32_t s = 0; s < code_length_chips; s++) { auto tmp_value = static_cast(tracking_code[s]); if (tmp_value < 0) { tmp_value = 0; } tmp_value = tmp_value | LOCAL_CODE_FPGA_ENABLE_WRITE_MEMORY; prn_codes_ptr_[static_cast(code_length_chips) * (PRN - 1) + s] = tmp_value; tmp_value = static_cast(data_code[s]); if (tmp_value < 0) { tmp_value = 0; } tmp_value = tmp_value | LOCAL_CODE_FPGA_ENABLE_WRITE_MEMORY | LOCAL_CODE_FPGA_CORRELATOR_SELECT_COUNT; data_codes_ptr_[static_cast(code_length_chips) * (PRN - 1) + s] = tmp_value; } } else { gps_l5i_code_gen_float(tracking_code, PRN); // The code is generated as a series of 1s and -1s. In order to store the values using only one bit, a -1 is stored as a 0 in the FPGA for (uint32_t s = 0; s < code_length_chips; s++) { auto tmp_value = static_cast(tracking_code[s]); if (tmp_value < 0) { tmp_value = 0; } tmp_value = tmp_value | LOCAL_CODE_FPGA_ENABLE_WRITE_MEMORY; prn_codes_ptr_[static_cast(code_length_chips) * (PRN - 1) + s] = tmp_value; } } } trk_params_fpga.ca_codes = prn_codes_ptr_; trk_params_fpga.data_codes = data_codes_ptr_; trk_params_fpga.code_length_chips = code_length_chips; trk_params_fpga.code_samples_per_chip = code_samples_per_chip; // 2 sample per chip trk_params_fpga.extended_correlation_in_fpga = false; // by default trk_params_fpga.extend_fpga_integration_periods = 1; // (number of FPGA integrations that are combined in the SW) trk_params_fpga.fpga_integration_period = 1; // (number of symbols that are effectively integrated in the FPGA) if (track_pilot_) { if (trk_params_fpga.extend_correlation_symbols > 1) { if (trk_params_fpga.extend_correlation_symbols <= GPS_L5I_NH_CODE_LENGTH) { if ((GPS_L5I_NH_CODE_LENGTH % trk_params_fpga.extend_correlation_symbols) == 0) { trk_params_fpga.extended_correlation_in_fpga = true; trk_params_fpga.fpga_integration_period = trk_params_fpga.extend_correlation_symbols; } } else { if (trk_params_fpga.extend_correlation_symbols % GPS_L5I_NH_CODE_LENGTH == 0) { trk_params_fpga.extended_correlation_in_fpga = true; trk_params_fpga.extend_fpga_integration_periods = trk_params_fpga.extend_correlation_symbols / GPS_L5I_NH_CODE_LENGTH; trk_params_fpga.fpga_integration_period = GPS_L5I_NH_CODE_LENGTH; } } } } // ################# MAKE TRACKING GNU Radio object ################### DLOG(INFO) << "role " << role_; tracking_fpga_sc_sptr_ = dll_pll_veml_make_tracking_fpga(trk_params_fpga); DLOG(INFO) << "tracking(" << tracking_fpga_sc_sptr_->unique_id() << ")"; 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"; } } GpsL5DllPllTrackingFpga::~GpsL5DllPllTrackingFpga() { volk_gnsssdr_free(prn_codes_ptr_); if (track_pilot_) { volk_gnsssdr_free(data_codes_ptr_); } } void GpsL5DllPllTrackingFpga::start_tracking() { tracking_fpga_sc_sptr_->start_tracking(); } void GpsL5DllPllTrackingFpga::stop_tracking() { tracking_fpga_sc_sptr_->stop_tracking(); } /* * Set tracking channel unique ID */ void GpsL5DllPllTrackingFpga::set_channel(unsigned int channel) { channel_ = channel; // UIO device file std::string device_io_name; // find the uio device file corresponding to the tracking multicorrelator if (find_uio_dev_file_name(device_io_name, device_name_, channel_ - num_prev_assigned_ch_) < 0) { std::cout << "Cannot find the FPGA uio device file corresponding to device name " << device_name_ << std::endl; throw std::exception(); } tracking_fpga_sc_sptr_->set_channel(channel_, device_io_name); } void GpsL5DllPllTrackingFpga::set_gnss_synchro(Gnss_Synchro *p_gnss_synchro) { tracking_fpga_sc_sptr_->set_gnss_synchro(p_gnss_synchro); } void GpsL5DllPllTrackingFpga::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 GpsL5DllPllTrackingFpga::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 GpsL5DllPllTrackingFpga::get_left_block() { return tracking_fpga_sc_sptr_; } gr::basic_block_sptr GpsL5DllPllTrackingFpga::get_right_block() { return tracking_fpga_sc_sptr_; }