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Add moving average smoother to carrier phase rate

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This commit is contained in:
Antonio Ramos
2018-09-07 00:06:06 +02:00
parent 47e5ef7f39
commit b66540b776
5 changed files with 33 additions and 15 deletions
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20
src/algorithms/libs/volk_gnsssdr_module/volk_gnsssdr/kernels/volk_gnsssdr/volk_gnsssdr_32fc_32f_high_dynamic_rotator_dot_prod_32fc_xn.h
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@@ -74,23 +74,18 @@
#include <volk_gnsssdr/volk_gnsssdr_complex.h>
#include <volk_gnsssdr/saturation_arithmetic.h>
#include <math.h>
//#include <stdio.h>
#ifdef LV_HAVE_GENERIC
static inline void volk_gnsssdr_32fc_32f_high_dynamic_rotator_dot_prod_32fc_xn_generic(lv_32fc_t* result, const lv_32fc_t* in_common, const lv_32fc_t phase_inc, const lv_32fc_t phase_inc_rate, lv_32fc_t* phase, const float** in_a, int num_a_vectors, unsigned int num_points)
{
lv_32fc_t tmp32_1, tmp32_2;
lv_32fc_t tmp32_1;
#ifdef __cplusplus
float d_arg = std::arg(phase_inc_rate) / 2.0;
// float d_arg = 0.5; //BORRAR
lv_32fc_t half_phase_inc_rate = std::exp(0.0, d_arg);
lv_32fc_t half_phase_inc_rate = std::sqrt(phase_inc_rate);
#else
float d_arg = carg(phase_inc_rate) / 2.0;
// float d_arg = 0.5; //BORRAR
lv_32fc_t half_phase_inc_rate = cexp(lv_cmake(0.0, d_arg));
lv_32fc_t half_phase_inc_rate = csqrtf(phase_inc_rate);
#endif
// lv_32fc_t half_phase_inc_rate = lv_cmake(0.0, 1.0); //BORRAR
lv_32fc_t constant_rotation = phase_inc * half_phase_inc_rate;
lv_32fc_t delta_phase_rate = lv_cmake(1.0, 0.0);
int n_vec;
unsigned int n;
@@ -104,7 +99,6 @@ static inline void volk_gnsssdr_32fc_32f_high_dynamic_rotator_dot_prod_32fc_xn_g
// Regenerate phase
if (n % 256 == 0)
{
//printf("Phase before regeneration %i: %f,%f Modulus: %f\n", n,lv_creal(*phase),lv_cimag(*phase), cabsf(*phase));
#ifdef __cplusplus
(*phase) /= std::abs((*phase));
delta_phase_rate /= std::abs(delta_phase_rate);
@@ -112,14 +106,12 @@ static inline void volk_gnsssdr_32fc_32f_high_dynamic_rotator_dot_prod_32fc_xn_g
(*phase) /= hypotf(lv_creal(*phase), lv_cimag(*phase));
delta_phase_rate /= hypotf(lv_creal(delta_phase_rate), lv_cimag(delta_phase_rate));
#endif
//printf("Phase after regeneration %i: %f,%f Modulus: %f\n", n,lv_creal(*phase),lv_cimag(*phase), cabsf(*phase));
}
(*phase) *= (phase_inc * half_phase_inc_rate * delta_phase_rate);
(*phase) *= (constant_rotation * delta_phase_rate);
delta_phase_rate *= phase_inc_rate;
for (n_vec = 0; n_vec < num_a_vectors; n_vec++)
{
tmp32_2 = tmp32_1 * in_a[n_vec][n];
result[n_vec] += tmp32_2;
result[n_vec] += (tmp32_1 * in_a[n_vec][n]);
}
}
}

25
src/algorithms/tracking/gnuradio_blocks/dll_pll_veml_tracking.cc
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@@ -58,6 +58,7 @@
#include <cmath>
#include <iostream>
#include <sstream>
#include <numeric>
using google::LogMessage;
@@ -405,6 +406,14 @@ dll_pll_veml_tracking::dll_pll_veml_tracking(const Dll_Pll_Conf &conf_) : gr::bl
d_last_prompt = gr_complex(0.0, 0.0);
d_state = 0; // initial state: standby
clear_tracking_vars();
if (trk_parameters.smoother_length > 0)
{
d_cp_history.resize(trk_parameters.smoother_length);
}
else
{
d_cp_history.resize(1);
}
}
@@ -450,7 +459,7 @@ void dll_pll_veml_tracking::start_tracking()
d_carrier_doppler_hz = d_acq_carrier_doppler_hz;
d_carrier_phase_step_rad = PI_2 * d_carrier_doppler_hz / trk_parameters.fs_in;
d_carrier_phase_rate_step_rad = 0.0;
d_cp_history.clear();
// DLL/PLL filter initialization
d_carrier_loop_filter.initialize(); // initialize the carrier filter
d_code_loop_filter.initialize(); // initialize the code filter
@@ -799,7 +808,21 @@ void dll_pll_veml_tracking::update_tracking_vars()
//################### PLL COMMANDS #################################################
// carrier phase step (NCO phase increment per sample) [rads/sample]
// carrier phase difference = carrier_phase(t2) - carrier_phase(t1)
double cp_diff = -d_carrier_phase_step_rad; // The previous cp value is stored in the variable
d_carrier_phase_step_rad = PI_2 * d_carrier_doppler_hz / trk_parameters.fs_in;
if (trk_parameters.use_high_dynamics_resampler)
{
cp_diff += d_carrier_phase_step_rad; // The new cp value is added to the previous in order to obtain the difference
// carrier phase rate step (NCO phase increment rate per sample) [rads/sample^2]
cp_diff /= static_cast<double>(d_current_prn_length_samples);
d_cp_history.push_back(cp_diff);
if (d_cp_history.full())
{
d_carrier_phase_rate_step_rad = std::accumulate(d_cp_history.begin(), d_cp_history.end(), 0.0) / static_cast<double>(d_cp_history.size());
}
}
// remnant carrier phase to prevent overflow in the code NCO
d_rem_carr_phase_rad += d_carrier_phase_step_rad * static_cast<double>(d_current_prn_length_samples);
d_rem_carr_phase_rad = fmod(d_rem_carr_phase_rad, PI_2);

1
src/algorithms/tracking/gnuradio_blocks/dll_pll_veml_tracking.h
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@@ -148,6 +148,7 @@ private:
double d_code_phase_rate_step_chips;
double d_carrier_phase_step_rad;
double d_carrier_phase_rate_step_rad;
boost::circular_buffer<double> d_cp_history;
// remaining code phase and carrier phase between tracking loops
double d_rem_code_phase_samples;
double d_rem_carr_phase_rad;

1
src/algorithms/tracking/libs/dll_pll_conf.cc
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@@ -37,6 +37,7 @@ Dll_Pll_Conf::Dll_Pll_Conf()
{
/* DLL/PLL tracking configuration */
use_high_dynamics_resampler = true;
smoother_length = 10;
fs_in = 0.0;
vector_length = 0U;
dump = false;

1
src/algorithms/tracking/libs/dll_pll_conf.h
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@@ -61,6 +61,7 @@ public:
int32_t carrier_lock_det_mav_samples;
int32_t cn0_min;
int32_t max_lock_fail;
uint32_t smoother_length;
double carrier_lock_th;
bool track_pilot;
char system;