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Merge branch 'ism' of github.com:carlesfernandez/gnss-sdr into ism

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Carles Fernandez 2024-09-20 17:06:22 +02:00
commit db78d104bf
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3 changed files with 60 additions and 10 deletions
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16
src/core/system_parameters/galileo_ism.cc
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@ -15,7 +15,6 @@
*/
#include "galileo_ism.h"
#include <boost/crc.hpp>
#include <boost/dynamic_bitset.hpp>
#include <algorithm>
#include <vector>
@ -176,15 +175,12 @@ uint16_t Galileo_ISM::get_Tvalidity_hours() const
}
bool Galileo_ISM::check_ism_crc(const std::bitset<GALILEO_DATA_JK_BITS>& bits) const
bool Galileo_ISM::check_ism_crc(const std::bitset<GALILEO_DATA_JK_BITS>& bits)
{
boost::dynamic_bitset<unsigned char> frame_bits(bits.to_string().substr(0, GALILEO_ISM_CRC_DATA_BITS));
std::vector<unsigned char> bytes;
boost::to_block_range(frame_bits, std::back_inserter(bytes));
std::reverse(bytes.begin(), bytes.end());
boost::crc_32_type crc32_ism;
crc32_ism.process_bytes(bytes.data(), GALILEO_ISM_CRC_DATA_BYTES);
const uint32_t crc_computed = crc32_ism.checksum();
if (this->ism_crc == crc_computed)
@ -193,4 +189,12 @@ bool Galileo_ISM::check_ism_crc(const std::bitset<GALILEO_DATA_JK_BITS>& bits) c
}
return false;
}
}
uint32_t Galileo_ISM::compute_crc(const std::vector<uint8_t>& data)
{
crc32_ism.process_bytes(data.data(), data.size());
uint32_t result = crc32_ism.checksum();
return result;
}

11
src/core/system_parameters/galileo_ism.h
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@ -19,9 +19,11 @@
#define GNSS_SDR_GALILEO_ISM_H
#include "Galileo_INAV.h"
#include <boost/crc.hpp>
#include <bitset>
#include <cstdint>
#include <unordered_map>
#include <vector>
/** \addtogroup Core
* \{ */
@ -41,7 +43,7 @@ public:
/*!
* Default constructor
*/
Galileo_ISM() = default;
Galileo_ISM() : crc32_ism(0x814141AB, 0, 0, false, false) {};
void set_ism_constellation_id(uint8_t const_id);
void set_ism_service_level_id(uint8_t sl_id);
@ -57,7 +59,7 @@ public:
void set_ism_Tvalidity(uint8_t tvalidity);
void set_ism_crc(uint32_t crc);
bool check_ism_crc(const std::bitset<GALILEO_DATA_JK_BITS>& bits) const;
bool check_ism_crc(const std::bitset<GALILEO_DATA_JK_BITS>& bits);
double get_pconst_value() const;
double get_psat_value() const;
@ -67,8 +69,11 @@ public:
uint16_t get_WN_ISM() const;
uint16_t get_t0_ISM() const;
uint16_t get_Tvalidity_hours() const;
uint32_t compute_crc(const std::vector<uint8_t>& data);
private:
boost::crc_basic<32> crc32_ism;
// ICD 2.1 Table 97
std::unordered_map<uint8_t, double> ISM_PCONST_MAP = {
{0, 1.0e-8},
@ -145,7 +150,6 @@ private:
{14, 3.75},
{15, 4.00}};
// ICD 2.1 Table 101
std::unordered_map<uint8_t, float> ISM_BNOM_MAP = {
{0, 0.0},
@ -165,7 +169,6 @@ private:
{14, 2.0},
{15, 2.4}};
// ICD 2.1 Table 102
std::unordered_map<uint8_t, uint16_t> ISM_TVALIDITY_MAP = {
{0, 1},

43
src/tests/unit-tests/system-parameters/galileo_ism_test.cc Normal file
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@ -0,0 +1,43 @@
/*!
* \file galileo_ism_test.cc
* \brief Tests for Galileo Integrity Support Message
* \author Carles Fernandez-Prades, 2024. cfernandez(at)cttc.es
*
*
* -----------------------------------------------------------------------------
*
* GNSS-SDR is a Global Navigation Satellite System software-defined receiver.
* This file is part of GNSS-SDR.
*
* Copyright (C) 2010-2023 (see AUTHORS file for a list of contributors)
* SPDX-License-Identifier: GPL-3.0-or-later
*
* -----------------------------------------------------------------------------
*/
#include "galileo_ism.h"
#include <gtest/gtest.h>
#include <algorithm>
#include <bitset>
#include <vector>
TEST(GalileoISMTest, CRC)
{
Galileo_ISM gal_ism{};
uint32_t expected_crc = 3002390191;
std::bitset<96> input{"010110000010101010101010101010101010101010101010101010101010101010101010101010101010101010101010"};
std::vector<uint8_t> data_bytes;
for (size_t i = 0; i < input.size(); i += 8)
{
std::bitset<8> byte;
for (size_t j = 0; j < 8; j++)
{
byte[j] = input[i + j];
}
data_bytes.push_back(static_cast<uint8_t>(byte.to_ulong()));
}
std::reverse(data_bytes.begin(), data_bytes.end());
auto computed_crc = gal_ism.compute_crc(data_bytes);
EXPECT_TRUE(computed_crc == expected_crc);
}