First working version of a complete 5 state Kalman filter for both carrier and code tracking, tested with GPS L1 CA 1ms integration.

src/algorithms/tracking/libs/CMakeLists.txt

@@ -21,6 +21,7 @@ set(TRACKING_LIB_SOURCES
     tracking_FLL_PLL_filter.cc
     tracking_loop_filter.cc
     dll_pll_conf.cc
+    kf_conf.cc
     bayesian_estimation.cc
     exponential_smoother.cc
 )
@@ -38,6 +39,7 @@ set(TRACKING_LIB_HEADERS
     tracking_FLL_PLL_filter.h
     tracking_loop_filter.h
     dll_pll_conf.h
+    kf_conf.h
     bayesian_estimation.h
     exponential_smoother.h
 )

src/algorithms/tracking/libs/kf_conf.cc

@@ -0,0 +1,151 @@
+/*!
+ * \file Kf_conf.cc
+ * \brief Class that contains all the configuration parameters for generic
+ * tracking block based on a DLL and a PLL.
+ * \author Javier Arribas, 2018. jarribas(at)cttc.es
+ *
+ * -----------------------------------------------------------------------------
+ *
+ * Copyright (C) 2010-2020  (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.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ *
+ * -----------------------------------------------------------------------------
+ */
+
+#include "kf_conf.h"
+#include "gnss_sdr_flags.h"
+#include "item_type_helpers.h"
+#include <glog/logging.h>
+
+
+Kf_Conf::Kf_Conf()
+{
+    /*KF tracking configuration */
+    high_dyn = false;
+    smoother_length = 10;
+    fs_in = 2000000.0;
+    vector_length = 0U;
+    dump = false;
+    dump_mat = true;
+    dump_filename = std::string("./Kf_dump.dat");
+
+    pull_in_time_s = 10;
+    bit_synchronization_time_limit_s = pull_in_time_s + 60;
+    early_late_space_chips = 0.25;
+    very_early_late_space_chips = 0.5;
+    early_late_space_narrow_chips = 0.15;
+    very_early_late_space_narrow_chips = 0.5;
+    slope = 1.0;
+    spc = 0.5;
+    y_intercept = 1.0;
+    carrier_aiding = true;
+    extend_correlation_symbols = 1;
+    cn0_samples = FLAGS_cn0_samples;
+    cn0_smoother_samples = 200;
+    cn0_smoother_alpha = 0.002;
+    carrier_lock_test_smoother_alpha = 0.002;
+    carrier_lock_test_smoother_samples = 25;
+    cn0_min = FLAGS_cn0_min;
+    max_carrier_lock_fail = FLAGS_max_carrier_lock_fail;
+    max_code_lock_fail = FLAGS_max_lock_fail;
+    carrier_lock_th = FLAGS_carrier_lock_th;
+    track_pilot = true;
+    enable_doppler_correction = false;
+    system = 'G';
+    signal[0] = '1';
+    signal[1] = 'C';
+    signal[2] = '\0';
+    item_type = "gr_complex";
+
+    expected_cn0_dbhz = 0;
+    //System covariances (Q)
+    code_phase_sd_chips = 0;
+    code_rate_sd_chips_s = 0;
+    carrier_phase_sd_rad = 0;
+    carrier_freq_sd_hz = 0;
+    carrier_freq_rate_sd_hz_s = 0;
+    //initial Kalman covariance matrix (P)
+    init_code_phase_sd_chips = 0;
+    init_code_rate_sd_chips_s = 0;
+    init_carrier_phase_sd_rad = 0;
+    init_carrier_freq_sd_hz = 0;
+    init_carrier_freq_rate_sd_hz_s = 0;
+
+    enable_dynamic_measurement_covariance = false;
+    use_estimated_cn0 = false;
+}
+
+
+void Kf_Conf::SetFromConfiguration(const ConfigurationInterface *configuration,
+    const std::string &role)
+{
+    item_type = configuration->property(role + ".item_type", item_type);
+    if (!item_type_valid(item_type))
+        {
+            LOG(WARNING) << "Unknown item type: " + item_type << ". Set to gr_complex";
+            item_type = "gr_complex";
+        }
+
+    double fs_in_deprecated = configuration->property("GNSS-SDR.internal_fs_hz", fs_in);
+    fs_in = configuration->property("GNSS-SDR.internal_fs_sps", fs_in_deprecated);
+    high_dyn = configuration->property(role + ".high_dyn", high_dyn);
+    dump = configuration->property(role + ".dump", dump);
+    dump_filename = configuration->property(role + ".dump_filename", dump_filename);
+    dump_mat = configuration->property(role + ".dump_mat", dump_mat);
+
+    pull_in_time_s = configuration->property(role + ".pull_in_time_s", pull_in_time_s);
+    bit_synchronization_time_limit_s = pull_in_time_s + 60;
+    early_late_space_chips = configuration->property(role + ".early_late_space_chips", early_late_space_chips);
+    early_late_space_narrow_chips = configuration->property(role + ".early_late_space_narrow_chips", early_late_space_narrow_chips);
+    very_early_late_space_chips = configuration->property(role + ".very_early_late_space_chips", very_early_late_space_chips);
+    very_early_late_space_narrow_chips = configuration->property(role + ".very_early_late_space_narrow_chips", very_early_late_space_narrow_chips);
+    extend_correlation_symbols = configuration->property(role + ".extend_correlation_symbols", extend_correlation_symbols);
+    track_pilot = configuration->property(role + ".track_pilot", track_pilot);
+    cn0_samples = configuration->property(role + ".cn0_samples", cn0_samples);
+    cn0_min = configuration->property(role + ".cn0_min", cn0_min);
+    max_code_lock_fail = configuration->property(role + ".max_lock_fail", max_code_lock_fail);
+    max_carrier_lock_fail = configuration->property(role + ".max_carrier_lock_fail", max_carrier_lock_fail);
+    carrier_lock_th = configuration->property(role + ".carrier_lock_th", carrier_lock_th);
+    carrier_aiding = configuration->property(role + ".carrier_aiding", carrier_aiding);
+
+    // tracking lock tests smoother parameters
+    cn0_smoother_samples = configuration->property(role + ".cn0_smoother_samples", cn0_smoother_samples);
+    cn0_smoother_alpha = configuration->property(role + ".cn0_smoother_alpha", cn0_smoother_alpha);
+    smoother_length = configuration->property(role + ".smoother_length", smoother_length);
+    if (smoother_length < 1)
+        {
+            smoother_length = 1;
+            LOG(WARNING) << "smoother_length must be bigger than 0. It has been set to 1";
+        }
+    carrier_lock_test_smoother_samples = configuration->property(role + ".carrier_lock_test_smoother_samples", carrier_lock_test_smoother_samples);
+    carrier_lock_test_smoother_alpha = configuration->property(role + ".carrier_lock_test_smoother_alpha", carrier_lock_test_smoother_alpha);
+
+    // Kalman filter covariances
+
+    //Measurement covariances (R)
+    expected_cn0_dbhz = configuration->property(role + ".expected_cn0_dbhz", 42.0);
+    enable_dynamic_measurement_covariance = configuration->property(role + ".enable_dynamic_measurement_covariance", false);
+    use_estimated_cn0 = configuration->property(role + ".use_estimated_cn0", false);
+
+    //System covariances (Q)
+    code_phase_sd_chips = configuration->property(role + ".code_phase_sd_chips", 0.001);
+    code_rate_sd_chips_s = configuration->property(role + ".code_rate_sd_chips_s", 0.001);
+
+    carrier_phase_sd_rad = configuration->property(role + ".carrier_phase_sd_rad", 0.001);
+    carrier_freq_sd_hz = configuration->property(role + ".carrier_freq_sd_hz", 0.1);
+    carrier_freq_rate_sd_hz_s = configuration->property(role + ".carrier_freq_rate_sd_hz_s", 1);
+
+    //initial Kalman covariance matrix (P)
+    init_code_phase_sd_chips = configuration->property(role + ".init_code_phase_sd_chips", 1);
+    init_code_rate_sd_chips_s = configuration->property(role + ".init_code_rate_sd_chips_s", 100);
+
+    init_carrier_phase_sd_rad = configuration->property(role + ".init_carrier_phase_sd_rad", 10);
+    init_carrier_freq_sd_hz = configuration->property(role + ".init_carrier_freq_sd_hz", 1000);
+    init_carrier_freq_rate_sd_hz_s = configuration->property(role + ".init_carrier_freq_rate_sd_hz_s", 1000);
+}

src/algorithms/tracking/libs/kf_conf.h

@@ -0,0 +1,91 @@
+/*!
+ * \file Kf_conf.h
+ * \brief Class that contains all the configuration parameters for generic tracking block based on a Kalman Filter.
+ * \author Javier Arribas, 2020. jarribas(at)cttc.es
+ *
+ * Class that contains all the configuration parameters for generic tracking block based on a DLL and a PLL.
+ *
+ * -----------------------------------------------------------------------------
+ *
+ * Copyright (C) 2010-2020  (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.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ *
+ * -----------------------------------------------------------------------------
+ */
+
+#ifndef GNSS_SDR_Kf_CONF_H
+#define GNSS_SDR_Kf_CONF_H
+
+#include "configuration_interface.h"
+#include <cstdint>
+#include <string>
+
+class Kf_Conf
+{
+public:
+    Kf_Conf();
+    void SetFromConfiguration(const ConfigurationInterface *configuration, const std::string &role);
+
+    std::string item_type;
+    std::string dump_filename;
+    double fs_in;
+    double carrier_lock_th;
+    float early_late_space_chips;
+    float very_early_late_space_chips;
+    float early_late_space_narrow_chips;
+    float very_early_late_space_narrow_chips;
+    float slope;
+    float spc;
+    float y_intercept;
+    float cn0_smoother_alpha;
+    float carrier_lock_test_smoother_alpha;
+    uint32_t pull_in_time_s;
+    uint32_t bit_synchronization_time_limit_s;
+    uint32_t vector_length;
+    uint32_t smoother_length;
+    int32_t extend_correlation_symbols;
+    int32_t cn0_samples;
+    int32_t cn0_smoother_samples;
+    int32_t carrier_lock_test_smoother_samples;
+    int32_t cn0_min;
+    int32_t max_code_lock_fail;
+    int32_t max_carrier_lock_fail;
+    char signal[3]{};
+    char system;
+    bool track_pilot;
+    bool enable_doppler_correction;
+    bool carrier_aiding;
+    bool high_dyn;
+    bool dump;
+    bool dump_mat;
+
+    //KF statistics
+    //states: code_phase_chips, carrier_phase_rads, carrier_freq_hz, carrier_freq_rate_hz_s, code_freq_rate_chips_s
+    //Measurement covariances (R)
+    double expected_cn0_dbhz;
+    //System covariances (Q)
+    double code_phase_sd_chips;
+    double code_rate_sd_chips_s;
+
+    double carrier_phase_sd_rad;
+    double carrier_freq_sd_hz;
+    double carrier_freq_rate_sd_hz_s;
+    //initial Kalman covariance matrix (P)
+    double init_code_phase_sd_chips;
+    double init_code_rate_sd_chips_s;
+
+    double init_carrier_phase_sd_rad;
+    double init_carrier_freq_sd_hz;
+    double init_carrier_freq_rate_sd_hz_s;
+
+    bool enable_dynamic_measurement_covariance;
+    bool use_estimated_cn0;
+};
+
+#endif