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Adding new resampler kernel and integrating it in the multicorrelator

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This commit is contained in:
Carles Fernandez
2016-03-30 21:33:43 +02:00
parent 70a2c5837c
commit 9eb175fb0e
4 changed files with 556 additions and 25 deletions
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src/algorithms/tracking/libs/cpu_multicorrelator.cc
+14 -21
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@@ -35,7 +35,6 @@
#include "cpu_multicorrelator.h"
#include <cmath>
#include <iostream>
#include <volk/volk.h>
#include <volk_gnsssdr/volk_gnsssdr.h>
@@ -68,10 +67,10 @@ bool cpu_multicorrelator::init(
// ALLOCATE MEMORY FOR INTERNAL vectors
size_t size = max_signal_length_samples * sizeof(std::complex<float>);
d_local_codes_resampled = static_cast<std::complex<float>**>(volk_malloc(n_correlators * sizeof(std::complex<float>), volk_get_alignment()));
d_local_codes_resampled = static_cast<std::complex<float>**>(volk_gnsssdr_malloc(n_correlators * sizeof(std::complex<float>), volk_gnsssdr_get_alignment()));
for (int n = 0; n < n_correlators; n++)
{
d_local_codes_resampled[n] = static_cast<std::complex<float>*>(volk_malloc(size, volk_get_alignment()));
d_local_codes_resampled[n] = static_cast<std::complex<float>*>(volk_gnsssdr_malloc(size, volk_gnsssdr_get_alignment()));
}
d_n_correlators = n_correlators;
return true;
@@ -100,23 +99,17 @@ bool cpu_multicorrelator::set_input_output_vectors(std::complex<float>* corr_out
return true;
}
void cpu_multicorrelator::update_local_code(int correlator_length_samples,float rem_code_phase_chips, float code_phase_step_chips)
void cpu_multicorrelator::update_local_code(int correlator_length_samples, float rem_code_phase_chips, float code_phase_step_chips)
{
int local_code_chip_index;
for (int current_correlator_tap = 0; current_correlator_tap < d_n_correlators; current_correlator_tap++)
{
for (int n = 0; n < correlator_length_samples; n++)
{
// resample code for current tap
local_code_chip_index = floor(code_phase_step_chips*static_cast<float>(n) + d_shifts_chips[current_correlator_tap]- rem_code_phase_chips);
local_code_chip_index = local_code_chip_index % d_code_length_chips;
//Take into account that in multitap correlators, the shifts can be negative!
if (local_code_chip_index < 0) local_code_chip_index += d_code_length_chips;
d_local_codes_resampled[current_correlator_tap][n] = d_local_code_in[local_code_chip_index];
}
}
volk_gnsssdr_32fc_xn_resampler_32fc_xn(d_local_codes_resampled,
d_local_code_in,
rem_code_phase_chips,
code_phase_step_chips,
d_shifts_chips,
correlator_length_samples,
d_n_correlators,
d_code_length_chips);
}
@@ -142,9 +135,9 @@ bool cpu_multicorrelator::free()
// Free memory
for (int n = 0; n < d_n_correlators; n++)
{
volk_free(d_local_codes_resampled[n]);
volk_gnsssdr_free(d_local_codes_resampled[n]);
}
volk_free(d_local_codes_resampled);
volk_gnsssdr_free(d_local_codes_resampled);
return true;
}