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Code cleaning

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git-svn-id: https://svn.code.sf.net/p/gnss-sdr/code/trunk@440 64b25241-fba3-4117-9849-534c7e92360d
This commit is contained in:
Carles Fernandez
2013-11-10 18:52:29 +00:00
parent 5b2abb62c2
commit aa5b531cd3
12 changed files with 751 additions and 788 deletions
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2
src/algorithms/telemetry_decoder/adapters/sbas_l1_telemetry_decoder.cc
View File

@@ -1,6 +1,6 @@
/*!
* \file sbas_l1_telemetry_decoder.cc
* \brief Implementation of an adapter of a SBAS telemtry data decoder block
* \brief Implementation of an adapter of a SBAS telemetry data decoder block
* to a TelemetryDecoderInterface
* \author Daniel Fehr 2013. daniel.co(at)bluewin.ch
*

5
src/algorithms/telemetry_decoder/adapters/sbas_l1_telemetry_decoder.h
View File

@@ -1,6 +1,6 @@
/*!
* \file sbas_l1_telemetry_decoder.h
* \brief Interface of an adapter of a SBAS telemtry data decoder block
* \brief Interface of an adapter of a SBAS telemetry data decoder block
* to a TelemetryDecoderInterface
* \author Daniel Fehr 2013. daniel.co(at)bluewin.ch
*
@@ -58,6 +58,9 @@ public:
return role_;
}
/*!
* \brief Returns "SBAS_L1_Telemetry_Decoder"
*/
std::string implementation()
{
return "SBAS_L1_Telemetry_Decoder";

101
src/algorithms/telemetry_decoder/gnuradio_blocks/sbas_l1_telemetry_decoder_cc.cc
View File

@@ -212,10 +212,11 @@ sbas_l1_telemetry_decoder_cc::sample_aligner::sample_aligner()
d_iir_par = 0.05;
reset();
}
sbas_l1_telemetry_decoder_cc::sample_aligner::~sample_aligner()
{
}
sbas_l1_telemetry_decoder_cc::sample_aligner::~sample_aligner()
{}
void sbas_l1_telemetry_decoder_cc::sample_aligner::reset()
{
@@ -225,6 +226,7 @@ void sbas_l1_telemetry_decoder_cc::sample_aligner::reset()
d_aligned = true;
}
/*
* samples length must be a multiple of two
*/
@@ -243,15 +245,15 @@ bool sbas_l1_telemetry_decoder_cc::sample_aligner::get_symbols(const std::vector
// get the next samples
for (int i = 0; i < d_n_smpls_in_history; i++)
{
smpls[i] = ((int)i_sym)*sbas_l1_telemetry_decoder_cc::d_samples_per_symbol+i-1 == -1 ? d_past_sample : samples[i_sym*sbas_l1_telemetry_decoder_cc::d_samples_per_symbol+i-1];
smpls[i] = ((int)i_sym)*sbas_l1_telemetry_decoder_cc::d_samples_per_symbol + i - 1 == -1 ? d_past_sample : samples[i_sym*sbas_l1_telemetry_decoder_cc::d_samples_per_symbol + i - 1];
}
// update the pseudo correlations (IIR method) of the two possible alignments
d_corr_paired = d_iir_par*smpls[1]*smpls[2] + (1-d_iir_par)*d_corr_paired;
d_corr_shifted = d_iir_par*smpls[0]*smpls[1] + (1-d_iir_par)*d_corr_shifted;
d_corr_paired = d_iir_par*smpls[1]*smpls[2] + (1 - d_iir_par)*d_corr_paired;
d_corr_shifted = d_iir_par*smpls[0]*smpls[1] + (1 - d_iir_par)*d_corr_shifted;
// decide which alignment is the correct one
corr_diff = std::abs(d_corr_paired-d_corr_shifted);
corr_diff = std::abs(d_corr_paired - d_corr_shifted);
stand_by = d_aligned ? corr_diff < d_corr_paired/2 : corr_diff < d_corr_shifted/2;
if (!stand_by)
{
@@ -259,7 +261,7 @@ bool sbas_l1_telemetry_decoder_cc::sample_aligner::get_symbols(const std::vector
}
// sum the correct pair of samples to a symbol, depending on the current alignment d_align
sym = smpls[0+int(d_aligned)*2] + smpls[1];
sym = smpls[0 + int(d_aligned)*2] + smpls[1];
symbols.push_back(sym);
// sample alignment debug output
@@ -278,13 +280,11 @@ bool sbas_l1_telemetry_decoder_cc::sample_aligner::get_symbols(const std::vector
double temp;
temp = samples.back();
d_past_sample = (temp);
return d_aligned;
}
// ### helper class for symbol alignment and viterbi decoding ###
sbas_l1_telemetry_decoder_cc::symbol_aligner_and_decoder::symbol_aligner_and_decoder()
{
// convolutional code properties
@@ -298,6 +298,8 @@ sbas_l1_telemetry_decoder_cc::symbol_aligner_and_decoder::symbol_aligner_and_dec
d_vd2 = new Viterbi_Decoder(g_encoder, d_KK, nn);
d_past_symbol = 0;
}
sbas_l1_telemetry_decoder_cc::symbol_aligner_and_decoder::~symbol_aligner_and_decoder()
{
delete d_vd1;
@@ -311,14 +313,11 @@ void sbas_l1_telemetry_decoder_cc::symbol_aligner_and_decoder::reset()
d_vd2->reset();
}
bool sbas_l1_telemetry_decoder_cc::symbol_aligner_and_decoder::
get_bits(const std::vector<double> symbols, std::vector<int> &bits)
bool sbas_l1_telemetry_decoder_cc::symbol_aligner_and_decoder::get_bits(const std::vector<double> symbols, std::vector<int> &bits)
{
const int traceback_depth = 5*d_KK;
int nbits_requested = symbols.size()/d_symbols_per_bit;
int nbits_decoded;
// fill two vectors with the two possible symbol alignments
std::vector<double> symbols_vd1(symbols); // aligned symbol vector -> copy input symbol vector
std::vector<double> symbols_vd2; // shifted symbol vector -> add past sample in front of input vector
@@ -327,15 +326,12 @@ get_bits(const std::vector<double> symbols, std::vector<int> &bits)
{
symbols_vd2.push_back(*symbol_it);
}
// arrays for decoded bits
int * bits_vd1 = new int[nbits_requested];
int * bits_vd2 = new int[nbits_requested];
// decode
float metric_vd1 = d_vd1->decode_continuous(symbols_vd1.data(), traceback_depth, bits_vd1, nbits_requested, nbits_decoded);
float metric_vd2 = d_vd2->decode_continuous(symbols_vd2.data(), traceback_depth, bits_vd2, nbits_requested, nbits_decoded);
// choose the bits with the better metric
for (int i = 0; i<nbits_decoded; i++)
{
@@ -348,36 +344,28 @@ get_bits(const std::vector<double> symbols, std::vector<int> &bits)
bits.push_back(bits_vd2[i]);
}
}
d_past_symbol = symbols.back();
delete[] bits_vd1;
delete[] bits_vd2;
return metric_vd1 > metric_vd2;
}
// ### helper class for detecting the preamble and collect the corresponding message candidates ###
void sbas_l1_telemetry_decoder_cc::frame_detector::reset()
{
d_buffer.clear();
}
void sbas_l1_telemetry_decoder_cc::frame_detector::
get_frame_candidates(const std::vector<int> bits, std::vector<std::pair<int,std::vector<int>>> &msg_candidates)
void sbas_l1_telemetry_decoder_cc::frame_detector::get_frame_candidates(const std::vector<int> bits, std::vector<std::pair<int,std::vector<int>>> &msg_candidates)
{
std::stringstream ss;
unsigned int sbas_msg_length = 250;
std::vector<std::vector<int>> preambles = {{0, 1, 0, 1, 0, 0, 1 ,1},
{1, 0, 0, 1, 1, 0, 1, 0},
{1, 1, 0, 0, 0, 1, 1, 0}};
{1, 0, 0, 1, 1, 0, 1, 0},
{1, 1, 0, 0, 0, 1, 1, 0}};
VLOG(FLOW) << "get_frame_candidates(): " << "d_buffer.size()=" << d_buffer.size() << "\tbits.size()=" << bits.size();
ss << "copy bits ";
int count = 0;
// copy new bits into the working buffer
@@ -388,7 +376,6 @@ get_frame_candidates(const std::vector<int> bits, std::vector<std::pair<int,std:
count++;
}
VLOG(SAMP_SYNC) << ss.str() << " into working buffer (" << count << " bits)";
int relative_preamble_start = 0;
while(d_buffer.size() >= sbas_msg_length)
{
@@ -400,22 +387,21 @@ get_frame_candidates(const std::vector<int> bits, std::vector<std::pair<int,std:
// compare the buffer bits with the preamble bits
for (std::vector<int>::iterator preample_bit_it = preample_it->begin(); preample_bit_it < preample_it->end(); ++preample_bit_it)
{
preamble_detected = *preample_bit_it == d_buffer[preample_bit_it-preample_it->begin()] ? preamble_detected : false ;
inv_preamble_detected = *preample_bit_it != d_buffer[preample_bit_it-preample_it->begin()] ? inv_preamble_detected : false ;
preamble_detected = *preample_bit_it == d_buffer[preample_bit_it - preample_it->begin()] ? preamble_detected : false ;
inv_preamble_detected = *preample_bit_it != d_buffer[preample_bit_it - preample_it->begin()] ? inv_preamble_detected : false ;
}
if (preamble_detected || inv_preamble_detected)
{
// copy candidate
std::vector<int> candidate;
std::copy(d_buffer.begin(), d_buffer.begin()+sbas_msg_length, std::back_inserter(candidate));
std::copy(d_buffer.begin(), d_buffer.begin() + sbas_msg_length, std::back_inserter(candidate));
if(inv_preamble_detected)
{
// invert bits
for (std::vector<int>::iterator candidate_bit_it = candidate.begin(); candidate_bit_it != candidate.end(); candidate_bit_it++)
*candidate_bit_it = *candidate_bit_it == 0 ? 1:0;
}
msg_candidates.push_back(std::pair<int,std::vector<int>>(relative_preamble_start,candidate));
msg_candidates.push_back(std::pair<int,std::vector<int>>(relative_preamble_start, candidate));
ss.str("");
ss << "preamble " << preample_it - preambles.begin() << (inv_preamble_detected?" inverted":" normal") << " detected! candidate=";
for (std::vector<int>::iterator bit_it = candidate.begin(); bit_it < candidate.end(); ++bit_it)
@@ -424,10 +410,8 @@ get_frame_candidates(const std::vector<int> bits, std::vector<std::pair<int,std:
}
}
relative_preamble_start++;
// remove bit in front
d_buffer.pop_front();
}
}
@@ -440,28 +424,22 @@ void sbas_l1_telemetry_decoder_cc::crc_verifier::reset()
}
void sbas_l1_telemetry_decoder_cc::crc_verifier::
get_valid_frames(const std::vector<msg_candiate_int_t> msg_candidates, std::vector<msg_candiate_char_t> &valid_msgs)
void sbas_l1_telemetry_decoder_cc::crc_verifier::get_valid_frames(const std::vector<msg_candiate_int_t> msg_candidates, std::vector<msg_candiate_char_t> &valid_msgs)
{
std::stringstream ss;
VLOG(FLOW) << "get_valid_frames(): " << "msg_candidates.size()=" << msg_candidates.size();
// for each candidate
for (std::vector<msg_candiate_int_t>::const_iterator candidate_it = msg_candidates.begin(); candidate_it < msg_candidates.end(); ++candidate_it)
{
// convert to bytes
std::vector<unsigned char> candidate_bytes;
zerropad_back_and_convert_to_bytes(candidate_it->second, candidate_bytes);
// verify CRC
d_checksum_agent.reset(0);
d_checksum_agent.process_bytes(candidate_bytes.data(), candidate_bytes.size());
unsigned int crc = d_checksum_agent.checksum();
VLOG(SAMP_SYNC) << "candidate " << candidate_it - msg_candidates.begin() << ": final crc remainder= " << std::hex << crc
<< std::setfill(' ') << std::resetiosflags(std::ios::hex);
// the final remainder must be zero for a valid message, because the CRC is done over the received CRC value
if (crc == 0)
{
@@ -481,25 +459,23 @@ get_valid_frames(const std::vector<msg_candiate_int_t> msg_candidates, std::vect
}
}
void sbas_l1_telemetry_decoder_cc::crc_verifier::
zerropad_back_and_convert_to_bytes(const std::vector<int> msg_candidate, std::vector<unsigned char> &bytes)
void sbas_l1_telemetry_decoder_cc::crc_verifier::zerropad_back_and_convert_to_bytes(const std::vector<int> msg_candidate, std::vector<unsigned char> &bytes)
{
std::stringstream ss;
const size_t bits_per_byte = 8;
unsigned char byte = 0;
VLOG(LMORE) << "zerropad_back_and_convert_to_bytes():" << byte;
for (std::vector<int>::const_iterator candidate_bit_it = msg_candidate.begin(); candidate_bit_it < msg_candidate.end(); ++candidate_bit_it)
{
int idx_bit = candidate_bit_it - msg_candidate.begin();
int bit_pos_in_current_byte = (bits_per_byte-1)-(idx_bit % bits_per_byte);
int bit_pos_in_current_byte = (bits_per_byte - 1) - (idx_bit % bits_per_byte);
byte |= (unsigned char)(*candidate_bit_it) << bit_pos_in_current_byte;
ss << *candidate_bit_it;
if (idx_bit % bits_per_byte == bits_per_byte-1)
if (idx_bit % bits_per_byte == bits_per_byte - 1)
{
bytes.push_back(byte);
VLOG(LMORE) << ss.str() << " -> byte=" << std::setw(2) << std::setfill('0') << std::hex << (unsigned int)byte; ss.str("");
@@ -511,52 +487,51 @@ zerropad_back_and_convert_to_bytes(const std::vector<int> msg_candidate, std::ve
<< std::setfill(' ') << std::resetiosflags(std::ios::hex);
}
void sbas_l1_telemetry_decoder_cc::crc_verifier::
zerropad_front_and_convert_to_bytes(const std::vector<int> msg_candidate, std::vector<unsigned char> &bytes)
void sbas_l1_telemetry_decoder_cc::crc_verifier::zerropad_front_and_convert_to_bytes(const std::vector<int> msg_candidate, std::vector<unsigned char> &bytes)
{
std::stringstream ss;
const size_t bits_per_byte = 8;
unsigned char byte = 0;
int idx_bit = 6; // insert 6 zeros at the front to fit the 250bits into a multiple of bytes
VLOG(LMORE) << "zerropad_front_and_convert_to_bytes():" << byte;
for (std::vector<int>::const_iterator candidate_bit_it = msg_candidate.begin(); candidate_bit_it < msg_candidate.end(); ++candidate_bit_it)
{
int bit_pos_in_current_byte = (bits_per_byte-1)-(idx_bit % bits_per_byte);
int bit_pos_in_current_byte = (bits_per_byte - 1) - (idx_bit % bits_per_byte);
byte |= (unsigned char)(*candidate_bit_it) << bit_pos_in_current_byte;
ss << *candidate_bit_it;
if (idx_bit % bits_per_byte == bits_per_byte-1)
if (idx_bit % bits_per_byte == bits_per_byte - 1)
{
bytes.push_back(byte);
VLOG(LMORE) << ss.str() << " -> byte=" << std::setw(2) << std::setfill('0') << std::hex << (unsigned int)byte; ss.str("");
byte = 0;
}
idx_bit++;
}
VLOG(LMORE) << " -> byte=" << std::setw(2) << std::setfill('0') << std::hex << (unsigned int)byte
<< std::setfill(' ') << std::resetiosflags(std::ios::hex);
}
void sbas_l1_telemetry_decoder_cc::set_raw_msg_queue(concurrent_queue<Sbas_Raw_Msg> *raw_msg_queue)
{
sbas_telemetry_data.set_raw_msg_queue(raw_msg_queue);
}
void sbas_l1_telemetry_decoder_cc::set_iono_queue(concurrent_queue<Sbas_Ionosphere_Correction> *iono_queue)
{
sbas_telemetry_data.set_iono_queue(iono_queue);
}
void sbas_l1_telemetry_decoder_cc::set_sat_corr_queue(concurrent_queue<Sbas_Satellite_Correction> *sat_corr_queue)
{
sbas_telemetry_data.set_sat_corr_queue(sat_corr_queue);
}
void sbas_l1_telemetry_decoder_cc::set_ephemeris_queue(concurrent_queue<Sbas_Ephemeris> *ephemeris_queue)
{
sbas_telemetry_data.set_ephemeris_queue(ephemeris_queue);

15
src/algorithms/telemetry_decoder/gnuradio_blocks/sbas_l1_telemetry_decoder_cc.h
View File

@@ -103,15 +103,12 @@ private:
public:
sample_aligner();
~sample_aligner();
void reset();
/*
* samples length must be a multiple of two
* for block operation the
*/
bool get_symbols(const std::vector<double> samples, std::vector<double> &symbols);
bool get_symbols(const std::vector<double> samples, std::vector<double> &symbols);
private:
int d_n_smpls_in_history ;
double d_iir_par;
@@ -128,11 +125,8 @@ private:
public:
symbol_aligner_and_decoder();
~symbol_aligner_and_decoder();
void reset();
bool get_bits(const std::vector<double> symbols, std::vector<int> &bits);
private:
int d_KK;
Viterbi_Decoder * d_vd1;
@@ -141,33 +135,32 @@ private:
} d_symbol_aligner_and_decoder;
// helper class for detecting the preamble and collect the corresponding message candidates
class frame_detector
{
public:
void reset();
void get_frame_candidates(const std::vector<int> bits, std::vector<std::pair<int, std::vector<int>>> &msg_candidates);
private:
std::deque<int> d_buffer;
} d_frame_detector;
// helper class for checking the CRC of the message candidates
class crc_verifier
{
public:
void reset();
void get_valid_frames(const std::vector<msg_candiate_int_t> msg_candidates, std::vector<msg_candiate_char_t> &valid_msgs);
private:
typedef boost::crc_optimal<24, 0x1864CFBu, 0x0, 0x0, false, false> crc_24_q_type;
crc_24_q_type d_checksum_agent;
void zerropad_front_and_convert_to_bytes(const std::vector<int> msg_candidate, std::vector<unsigned char> &bytes);
void zerropad_back_and_convert_to_bytes(const std::vector<int> msg_candidate, std::vector<unsigned char> &bytes);
} d_crc_verifier;
Sbas_Telemetry_Data sbas_telemetry_data;
};