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gnss-sdr/src/algorithms/libs/galileo_e6_signal_replica.cc

255 lines
9.2 KiB
C++

/*!
* \file galileo_e6_signal_replica.cc
* \brief This library implements various functions for Galileo E6 signal
* replica generation
* \author Carles Fernandez-Prades, 2020. cfernandez(at)cttc.es
*
*
* -----------------------------------------------------------------------------
*
* 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 "galileo_e6_signal_replica.h"
#include "Galileo_E6.h"
#include "gnss_signal_replica.h"
#include <utility>
#include <vector>
void galileo_e6_b_code_gen_complex_primary(own::span<std::complex<float>> dest,
int32_t prn)
{
const uint32_t prn_ = prn - 1;
uint32_t index = 0;
std::array<int32_t, 4> a{};
if ((prn < 1) || (prn > 50))
{
return;
}
for (size_t i = 0; i < GALILEO_E6_B_PRIMARY_CODE_STR_LENGTH - 1; i++)
{
hex_to_binary_converter(a, GALILEO_E6_B_PRIMARY_CODE[prn_][i]);
dest[index] = std::complex<float>(static_cast<float>(a[0]), 0.0);
dest[index + 1] = std::complex<float>(static_cast<float>(a[1]), 0.0);
dest[index + 2] = std::complex<float>(static_cast<float>(a[2]), 0.0);
dest[index + 3] = std::complex<float>(static_cast<float>(a[3]), 0.0);
index = index + 4;
}
// last bit is filled up with a zero
hex_to_binary_converter(a, GALILEO_E6_B_PRIMARY_CODE[prn_][GALILEO_E6_B_PRIMARY_CODE_STR_LENGTH - 1]);
dest[index] = std::complex<float>(static_cast<float>(a[0]), 0.0);
dest[index + 1] = std::complex<float>(static_cast<float>(a[1]), 0.0);
dest[index + 2] = std::complex<float>(static_cast<float>(a[2]), 0.0);
}
void galileo_e6_b_code_gen_float_primary(own::span<float> dest, int32_t prn)
{
const uint32_t prn_ = prn - 1;
uint32_t index = 0;
std::array<int32_t, 4> a{};
if ((prn < 1) || (prn > 50))
{
return;
}
for (size_t i = 0; i < GALILEO_E6_B_PRIMARY_CODE_STR_LENGTH - 1; i++)
{
hex_to_binary_converter(a, GALILEO_E6_B_PRIMARY_CODE[prn_][i]);
dest[index] = static_cast<float>(a[0]);
dest[index + 1] = static_cast<float>(a[1]);
dest[index + 2] = static_cast<float>(a[2]);
dest[index + 3] = static_cast<float>(a[3]);
index = index + 4;
}
// last bit is filled up with a zero
hex_to_binary_converter(a, GALILEO_E6_B_PRIMARY_CODE[prn_][GALILEO_E6_B_PRIMARY_CODE_STR_LENGTH - 1]);
dest[index] = static_cast<float>(a[0]);
dest[index + 1] = static_cast<float>(a[1]);
dest[index + 2] = static_cast<float>(a[2]);
}
void galileo_e6_b_code_gen_complex_sampled(own::span<std::complex<float>> dest,
uint32_t prn,
int32_t sampling_freq,
uint32_t chip_shift)
{
constexpr uint32_t codeLength = GALILEO_E6_B_CODE_LENGTH_CHIPS;
constexpr int32_t codeFreqBasis = GALILEO_E6_B_CODE_CHIP_RATE_CPS;
const auto samplesPerCode = static_cast<uint32_t>(static_cast<double>(sampling_freq) / (static_cast<double>(codeFreqBasis) / static_cast<double>(codeLength)));
const uint32_t delay = ((codeLength - chip_shift) % codeLength) * samplesPerCode / codeLength;
std::vector<std::complex<float>> code_aux(codeLength);
galileo_e6_b_code_gen_complex_primary(code_aux, prn);
if (sampling_freq != codeFreqBasis)
{
std::vector<std::complex<float>> resampled_signal_aux(samplesPerCode);
resampler(code_aux, resampled_signal_aux, codeFreqBasis, sampling_freq); // resamples code to sampling_freq
code_aux = std::move(resampled_signal_aux);
}
for (uint32_t i = 0; i < samplesPerCode; i++)
{
dest[(i + delay) % samplesPerCode] = code_aux[i];
}
}
void galileo_e6_c_code_gen_complex_primary(own::span<std::complex<float>> dest,
int32_t prn)
{
const uint32_t prn_ = prn - 1;
uint32_t index = 0;
std::array<int32_t, 4> a{};
if ((prn < 1) || (prn > 50))
{
return;
}
for (size_t i = 0; i < GALILEO_E6_C_PRIMARY_CODE_STR_LENGTH - 1; i++)
{
hex_to_binary_converter(a, GALILEO_E6_C_PRIMARY_CODE[prn_][i]);
dest[index] = std::complex<float>(static_cast<float>(a[0]), 0.0);
dest[index + 1] = std::complex<float>(static_cast<float>(a[1]), 0.0);
dest[index + 2] = std::complex<float>(static_cast<float>(a[2]), 0.0);
dest[index + 3] = std::complex<float>(static_cast<float>(a[3]), 0.0);
index = index + 4;
}
// last bit is filled up with a zero
hex_to_binary_converter(a, GALILEO_E6_C_PRIMARY_CODE[prn_][GALILEO_E6_C_PRIMARY_CODE_STR_LENGTH - 1]);
dest[index] = std::complex<float>(static_cast<float>(a[0]), 0.0);
dest[index + 1] = std::complex<float>(static_cast<float>(a[1]), 0.0);
dest[index + 2] = std::complex<float>(static_cast<float>(a[2]), 0.0);
}
void galileo_e6_c_code_gen_float_primary(own::span<float> dest, int32_t prn)
{
const uint32_t prn_ = prn - 1;
uint32_t index = 0;
std::array<int32_t, 4> a{};
if ((prn < 1) || (prn > 50))
{
return;
}
for (size_t i = 0; i < GALILEO_E6_C_PRIMARY_CODE_STR_LENGTH - 1; i++)
{
hex_to_binary_converter(a, GALILEO_E6_C_PRIMARY_CODE[prn_][i]);
dest[index] = static_cast<float>(a[0]);
dest[index + 1] = static_cast<float>(a[1]);
dest[index + 2] = static_cast<float>(a[2]);
dest[index + 3] = static_cast<float>(a[3]);
index = index + 4;
}
// last bit is filled up with a zero
hex_to_binary_converter(a, GALILEO_E6_C_PRIMARY_CODE[prn_][GALILEO_E6_C_PRIMARY_CODE_STR_LENGTH - 1]);
dest[index] = static_cast<float>(a[0]);
dest[index + 1] = static_cast<float>(a[1]);
dest[index + 2] = static_cast<float>(a[2]);
}
void galileo_e6_c_code_gen_complex_sampled(own::span<std::complex<float>> dest,
uint32_t prn,
int32_t sampling_freq,
uint32_t chip_shift)
{
constexpr uint32_t codeLength = GALILEO_E6_C_CODE_LENGTH_CHIPS;
constexpr int32_t codeFreqBasis = GALILEO_E6_C_CODE_CHIP_RATE_CPS;
const auto samplesPerCode = static_cast<uint32_t>(static_cast<double>(sampling_freq) / (static_cast<double>(codeFreqBasis) / static_cast<double>(codeLength)));
const uint32_t delay = ((codeLength - chip_shift) % codeLength) * samplesPerCode / codeLength;
std::vector<std::complex<float>> code_aux(codeLength);
galileo_e6_c_code_gen_complex_primary(code_aux, prn);
if (sampling_freq != codeFreqBasis)
{
std::vector<std::complex<float>> resampled_signal_aux(samplesPerCode);
resampler(code_aux, resampled_signal_aux, codeFreqBasis, sampling_freq); // resamples code to sampling_freq
code_aux = std::move(resampled_signal_aux);
}
for (uint32_t i = 0; i < samplesPerCode; i++)
{
dest[(i + delay) % samplesPerCode] = code_aux[i];
}
}
void galileo_e6_c_secondary_code_gen_complex(own::span<std::complex<float>> dest,
int32_t prn)
{
const uint32_t prn_ = prn - 1;
uint32_t index = 0;
std::array<int32_t, 4> a{};
if ((prn < 1) || (prn > 50))
{
return;
}
for (size_t i = 0; i < GALILEO_E6_C_SECONDARY_CODE_STR_LENGTH; i++)
{
hex_to_binary_converter(a, GALILEO_E6_C_SECONDARY_CODE[prn_][i]);
dest[index] = std::complex<float>(static_cast<float>(a[0]), 0.0);
dest[index + 1] = std::complex<float>(static_cast<float>(a[1]), 0.0);
dest[index + 2] = std::complex<float>(static_cast<float>(a[2]), 0.0);
dest[index + 3] = std::complex<float>(static_cast<float>(a[3]), 0.0);
index = index + 4;
}
}
void galileo_e6_c_secondary_code_gen_float(own::span<float> dest,
int32_t prn)
{
const uint32_t prn_ = prn - 1;
uint32_t index = 0;
std::array<int32_t, 4> a{};
if ((prn < 1) || (prn > 50))
{
return;
}
for (size_t i = 0; i < GALILEO_E6_C_SECONDARY_CODE_STR_LENGTH; i++)
{
hex_to_binary_converter(a, GALILEO_E6_C_SECONDARY_CODE[prn_][i]);
dest[index] = static_cast<float>(a[0]);
dest[index + 1] = static_cast<float>(a[1]);
dest[index + 2] = static_cast<float>(a[2]);
dest[index + 3] = static_cast<float>(a[3]);
index = index + 4;
}
}
std::string galileo_e6_c_secondary_code(int32_t prn)
{
std::string dest(static_cast<size_t>(GALILEO_E6_C_SECONDARY_CODE_LENGTH_CHIPS), '0');
const uint32_t prn_ = prn - 1;
if ((prn < 1) || (prn > 50))
{
return dest;
}
uint32_t index = 0;
for (size_t i = 0; i < GALILEO_E6_C_SECONDARY_CODE_STR_LENGTH; i++)
{
std::string aux = hex_to_binary_string(GALILEO_E6_C_SECONDARY_CODE[prn_][i]);
dest[index] = aux[0];
dest[index + 1] = aux[1];
dest[index + 2] = aux[2];
dest[index + 3] = aux[3];
index = index + 4;
}
return dest;
}