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Code Issues Releases Wiki Activity

GPS CNAV telemetry page decoder is finally working!

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This commit is contained in:
Javier
2015-05-29 16:06:22 +02:00
parent 4fe35f760b
commit f56348d2d7
5 changed files with 56 additions and 30 deletions
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33
src/algorithms/telemetry_decoder/gnuradio_blocks/gps_l2_m_telemetry_decoder_cc.cc
View File

@@ -180,7 +180,7 @@ int gps_l2_m_telemetry_decoder_cc::general_work (int noutput_items, gr_vector_in
// verify checksum
// and return the valid messages
std::vector<msg_candiate_char_t> valid_msgs;
std::vector<msg_candiate_int_t> valid_msgs;
d_crc_verifier.get_valid_frames(msg_candidates, valid_msgs);
if (valid_msgs.size()==0)
{
@@ -193,7 +193,14 @@ int gps_l2_m_telemetry_decoder_cc::general_work (int noutput_items, gr_vector_in
}
}else{ //at least one frame has good CRC, keep the invert sign for the next frames
d_flag_invert_input_symbols=d_flag_invert_buffer_symbols;
std::vector<int> tmp_msg;
std::string msg;
LOG(INFO)<<valid_msgs.size()<<" GOOD L2C CNAV FRAME DETECTED!";
for (int i=0;i<valid_msgs.size();i++)
{
tmp_msg =valid_msgs.at(i).second;
d_CNAV_Message.decode_page(tmp_msg);
}
break;
}
}
@@ -411,9 +418,9 @@ void gps_l2_m_telemetry_decoder_cc::crc_verifier::reset()
}
void gps_l2_m_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 gps_l2_m_telemetry_decoder_cc::crc_verifier::get_valid_frames(const std::vector<msg_candiate_int_t> msg_candidates, std::vector<msg_candiate_int_t> &valid_msgs)
{
std::stringstream ss;
std::vector <unsigned char> tmp_msg;
LOG(INFO) << "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)
@@ -430,19 +437,9 @@ void gps_l2_m_telemetry_decoder_cc::crc_verifier::get_valid_frames(const std::ve
// the final remainder must be zero for a valid message, because the CRC is done over the received CRC value
if (crc == 0)
{
valid_msgs.push_back(msg_candiate_char_t(candidate_it->first, candidate_bytes));
ss << "Valid message found!";
valid_msgs.push_back(msg_candiate_int_t(candidate_it->first, candidate_it->second));
std::cout << "Valid CNAV message found!"<<std::endl;
}
else
{
ss << "Not a valid message.";
}
//ss << " Relbitoffset=" << candidate_it->first << " content=";
for (std::vector<unsigned char>::iterator byte_it = candidate_bytes.begin(); byte_it < candidate_bytes.end(); ++byte_it)
{
ss << std::setw(2) << std::setfill('0') << std::hex << (unsigned int)(*byte_it);
}
LOG(INFO) << ss.str() << std::setfill(' ') << std::resetiosflags(std::ios::hex) << std::endl;
}
}
@@ -470,9 +467,9 @@ void gps_l2_m_telemetry_decoder_cc::crc_verifier::zerropad_back_and_convert_to_b
}
}
bytes.push_back(byte); // implies: insert 6 zeros at the end to fit the 250bits into a multiple of bytes
LOG(INFO) << " -> byte=" << std::setw(2)
<< std::setfill('0') << std::hex << (unsigned int)byte
<< std::setfill(' ') << std::resetiosflags(std::ios::hex);
//LOG(INFO) << " -> byte=" << std::setw(2)
// << std::setfill('0') << std::hex << (unsigned int)byte
// << std::setfill(' ') << std::resetiosflags(std::ios::hex);
}

6
src/algorithms/telemetry_decoder/gnuradio_blocks/gps_l2_m_telemetry_decoder_cc.h
View File

@@ -42,7 +42,7 @@
#include <gnuradio/msg_queue.h>
#include "gnss_satellite.h"
#include "viterbi_decoder.h"
//#include "sbas_telemetry_data.h"
#include "gps_cnav_navigation_message.h"
class gps_l2_m_telemetry_decoder_cc;
@@ -146,7 +146,7 @@ private:
{
public:
void reset();
void get_valid_frames(const std::vector<msg_candiate_int_t> msg_candidates, std::vector<msg_candiate_char_t> &valid_msgs);
void get_valid_frames(const std::vector<msg_candiate_int_t> msg_candidates, std::vector<msg_candiate_int_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;
@@ -155,7 +155,7 @@ private:
} d_crc_verifier;
//Sbas_Telemetry_Data sbas_telemetry_data;
Gps_CNAV_Navigation_Message d_CNAV_Message;
};