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Adding Galileo-GPS system time parameters. Fixes in tracking

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This commit is contained in:
Carles Fernandez
2014-08-31 13:21:41 +02:00
parent 14970bf2c3
commit ad5fd36719
15 changed files with 165 additions and 28 deletions
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46
src/algorithms/telemetry_decoder/gnuradio_blocks/galileo_e1b_telemetry_decoder_cc.cc
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@@ -169,7 +169,7 @@ galileo_e1b_telemetry_decoder_cc::galileo_e1b_telemetry_decoder_cc(
d_flag_parity = false;
d_TOW_at_Preamble = 0;
d_TOW_at_current_symbol = 0;
delta_t = 0;
d_CRC_error_counter = 0;
}
@@ -262,6 +262,28 @@ void galileo_e1b_telemetry_decoder_cc::decode_word(double *page_part_symbols,int
//std::cout<<"New Galileo UTC model received for SV "<<d_satellite.get_PRN()<<std::endl;
d_utc_model_queue->push(utc_model);
}
if (d_nav.have_new_almanac()==true)
{
Galileo_Almanac almanac=d_nav.get_almanac();
d_almanac_queue->push(almanac);
//debug
std::cout<<"Almanac received!"<<std::endl;
std::cout<<"GPS_to_Galileo time conversion:"<<std::endl;
std::cout<<"A0G="<<almanac.A_0G_10<<std::endl;
std::cout<<"A1G="<<almanac.A_1G_10<<std::endl;
std::cout<<"T0G="<<almanac.t_0G_10<<std::endl;
std::cout<<"WN_0G_10="<<almanac.WN_0G_10<<std::endl;
std::cout<<"Actual parameters:"<<std::endl;
std::cout<<"d_TOW_at_current_symbol="<<d_TOW_at_current_symbol<<std::endl;
std::cout<<"d_nav.WN_0="<<d_nav.WN_0<<std::endl;
delta_t=almanac.A_0G_10+almanac.A_1G_10*(d_TOW_at_current_symbol-almanac.t_0G_10+604800*(fmod((d_nav.WN_0-almanac.WN_0G_10),64)));
std::cout<<"delta_t="<<delta_t<<"[s]"<<std::endl;
}
}
@@ -396,6 +418,10 @@ int galileo_e1b_telemetry_decoder_cc::general_work (int noutput_items, gr_vector
//2. Add the telemetry decoder information
if (this->d_flag_preamble == true and d_nav.flag_TOW_set == true)
//update TOW at the preamble instant
// JAVI: 30/06/2014
// TOW, in Galileo, is referred to the START of the PAGE PART, that is, THE FIRST SYMBOL OF THAT PAGE, NOT THE PREAMBLE.
// thus, no correction should be done. d_TOW_at_Preamble should be renamed to d_TOW_at_page_start.
// Sice we detected the preable, then, we are in the last symbol of that preable, or just at the start of the first page symbol.
//flag preamble is true after the all page (even and odd) is recevived. I/NAV page period is 2 SECONDS
{
Prn_timestamp_at_preamble_ms = in[0][0].Tracking_timestamp_secs * 1000.0;
@@ -406,7 +432,7 @@ int galileo_e1b_telemetry_decoder_cc::general_work (int noutput_items, gr_vector
/* 1 sec (GALILEO_INAV_PAGE_PART_SYMBOLS*GALIELO_E1_CODE_PERIOD) is added because
* if we have a TOW value it means that we are at the begining of the last page part
* (GNU Radio history keeps in a buffer the rest of the incomming frame part)*/
d_TOW_at_current_symbol = d_TOW_at_Preamble;// + GALILEO_INAV_PAGE_PART_SYMBOLS*GALIELO_E1_CODE_PERIOD;
d_TOW_at_current_symbol=d_TOW_at_Preamble;//-GALIELO_E1_CODE_PERIOD;//+ (double)GALILEO_INAV_PREAMBLE_LENGTH_BITS/(double)GALILEO_TELEMETRY_RATE_BITS_SECOND;
d_nav.flag_TOW_5 = false;
}
@@ -418,12 +444,12 @@ int galileo_e1b_telemetry_decoder_cc::general_work (int noutput_items, gr_vector
/* 1 sec (GALILEO_INAV_PAGE_PART_SYMBOLS*GALIELO_E1_CODE_PERIOD) is added because
* if we have a TOW value it means that we are at the begining of the last page part
* (GNU Radio history keeps in a buffer the rest of the incomming frame part)*/
d_TOW_at_current_symbol = d_TOW_at_Preamble;// + GALILEO_INAV_PAGE_PART_SYMBOLS*GALIELO_E1_CODE_PERIOD;
d_TOW_at_current_symbol=d_TOW_at_Preamble;//-GALIELO_E1_CODE_PERIOD;//+ (double)GALILEO_INAV_PREAMBLE_LENGTH_BITS/(double)GALILEO_TELEMETRY_RATE_BITS_SECOND;
d_nav.flag_TOW_6 = false;
}
else
{
//this page has no timming information
//this page has no timing information
d_TOW_at_Preamble = d_TOW_at_Preamble + GALILEO_INAV_PAGE_SECONDS;
d_TOW_at_current_symbol = d_TOW_at_current_symbol + GALIELO_E1_CODE_PERIOD;// + GALILEO_INAV_PAGE_PART_SYMBOLS*GALIELO_E1_CODE_PERIOD;
}
@@ -435,6 +461,14 @@ int galileo_e1b_telemetry_decoder_cc::general_work (int noutput_items, gr_vector
}
//if (d_flag_frame_sync == true and d_nav.flag_TOW_set==true and d_nav.flag_CRC_test == true)
if(d_nav.flag_GGTO_1 == true and d_nav.flag_GGTO_2 == true and d_nav.flag_GGTO_3 == true and d_nav.flag_GGTO_4 == true) //all GGTO parameters arrived
{
delta_t=d_nav.A_0G_10+d_nav.A_1G_10*(d_TOW_at_current_symbol-d_nav.t_0G_10+604800.0*(fmod((d_nav.WN_0-d_nav.WN_0G_10),64)));
}
if (d_flag_frame_sync == true and d_nav.flag_TOW_set == true)
{
current_synchro_data.Flag_valid_word = true;
@@ -446,7 +480,9 @@ int galileo_e1b_telemetry_decoder_cc::general_work (int noutput_items, gr_vector
current_synchro_data.d_TOW = d_TOW_at_Preamble;
current_synchro_data.d_TOW_at_current_symbol = d_TOW_at_current_symbol;
current_synchro_data.Flag_preamble = d_flag_preamble;
current_synchro_data.d_TOW_hybrid_at_current_symbol= current_synchro_data.d_TOW_at_current_symbol - delta_t; //delta_t = t_gal - t_gps ----> t_gps = t_gal -delta_t
DLOG(INFO)<< "delta_t = " << delta_t << std::endl;
current_synchro_data.Flag_preamble = d_flag_preamble;
current_synchro_data.Prn_timestamp_ms = in[0][0].Tracking_timestamp_secs * 1000.0;
current_synchro_data.Prn_timestamp_at_preamble_ms = Prn_timestamp_at_preamble_ms;

2
src/algorithms/telemetry_decoder/gnuradio_blocks/galileo_e1b_telemetry_decoder_cc.h
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@@ -138,6 +138,8 @@ private:
double d_TOW_at_current_symbol;
double Prn_timestamp_at_preamble_ms;
bool flag_TOW_set;
double delta_t; //GPS-GALILEO time offset
std::string d_dump_filename;
std::ofstream d_dump_file;

36
src/algorithms/telemetry_decoder/gnuradio_blocks/gps_l1_ca_telemetry_decoder_cc.cc
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@@ -130,7 +130,7 @@ gps_l1_ca_telemetry_decoder_cc::gps_l1_ca_telemetry_decoder_cc(
d_TOW_at_Preamble = 0;
d_TOW_at_current_symbol = 0;
flag_TOW_set = false;
d_average_count=0;
//set_history(d_samples_per_bit*8); // At least a history of 8 bits are needed to correlate with the preamble
}
@@ -301,10 +301,15 @@ int gps_l1_ca_telemetry_decoder_cc::general_work (int noutput_items, gr_vector_i
//1. Copy the current tracking output
current_synchro_data = in[0][0];
//2. Add the telemetry decoder information
if (this->d_flag_preamble == true and d_GPS_FSM.d_nav.d_TOW > 0) //update TOW at the preamble instant (todo: check for valid d_TOW)
if (this->d_flag_preamble == true and d_GPS_FSM.d_nav.d_TOW > 0)
//update TOW at the preamble instant (todo: check for valid d_TOW)
// JAVI: 30/06/2014
// TOW, in GPS, is referred to the START of the SUBFRAME, that is, THE FIRST SYMBOL OF THAT SUBFRAME, NOT THE PREAMBLE.
// thus, no correction should be done. d_TOW_at_Preamble should be renamed to d_TOW_at_subframe_start.
// Sice we detected the preable, then, we are in the last symbol of that preamble, or just at the start of the first subframe symbol.
{
d_TOW_at_Preamble = d_GPS_FSM.d_nav.d_TOW + GPS_SUBFRAME_SECONDS; //we decoded the current TOW when the last word of the subframe arrive, so, we have a lag of ONE SUBFRAME
d_TOW_at_current_symbol = d_TOW_at_Preamble + GPS_CA_PREAMBLE_LENGTH_BITS/GPS_CA_TELEMETRY_RATE_BITS_SECOND;
d_TOW_at_current_symbol = d_TOW_at_Preamble;//GPS_L1_CA_CODE_PERIOD;// + (double)GPS_CA_PREAMBLE_LENGTH_BITS/(double)GPS_CA_TELEMETRY_RATE_BITS_SECOND;
Prn_timestamp_at_preamble_ms = in[0][0].Tracking_timestamp_secs * 1000.0;
if (flag_TOW_set == false)
{
@@ -318,6 +323,8 @@ int gps_l1_ca_telemetry_decoder_cc::general_work (int noutput_items, gr_vector_i
current_synchro_data.d_TOW = d_TOW_at_Preamble;
current_synchro_data.d_TOW_at_current_symbol = d_TOW_at_current_symbol;
current_synchro_data.d_TOW_hybrid_at_current_symbol= current_synchro_data.d_TOW_at_current_symbol; // to be used in the hybrid configuration
current_synchro_data.Flag_valid_word = (d_flag_frame_sync == true and d_flag_parity == true and flag_TOW_set==true);
current_synchro_data.Flag_preamble = d_flag_preamble;
current_synchro_data.Prn_timestamp_ms = in[0][0].Tracking_timestamp_secs * 1000.0;
@@ -341,12 +348,29 @@ int gps_l1_ca_telemetry_decoder_cc::general_work (int noutput_items, gr_vector_i
LOG(WARNING) << "Exception writing observables dump file " << e.what();
}
}
//3. Make the output (copy the object contents to the GNURadio reserved memory)
*out[0] = current_synchro_data;
return 1;
//todo: implement averaging
d_average_count++;
if (d_average_count==d_decimation_output_factor)
{
d_average_count=0;
//3. Make the output (copy the object contents to the GNURadio reserved memory)
*out[0] = current_synchro_data;
//std::cout<<"GPS TLM output on CH="<<this->d_channel << " SAMPLE STAMP="<<d_sample_counter/d_decimation_output_factor<<std::endl;
return 1;
}else{
return 0;
}
}
void gps_l1_ca_telemetry_decoder_cc::set_decimation(int decimation)
{
d_decimation_output_factor=decimation;
}
void gps_l1_ca_telemetry_decoder_cc::set_satellite(Gnss_Satellite satellite)
{
d_satellite = Gnss_Satellite(satellite.get_system(), satellite.get_PRN());

10
src/algorithms/telemetry_decoder/gnuradio_blocks/gps_l1_ca_telemetry_decoder_cc.h
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@@ -61,6 +61,12 @@ public:
void set_satellite(Gnss_Satellite satellite); //!< Set satellite PRN
void set_channel(int channel); //!< Set receiver's channel
/*!
* \brief Set decimation factor to average the GPS synchronization estimation output from the tracking module.
*/
void set_decimation(int decimation);
/*!
* \brief Set the satellite data queue
*/
@@ -114,6 +120,10 @@ private:
bool d_flag_preamble;
int d_word_number;
// output averaging and decimation
int d_average_count;
int d_decimation_output_factor;
long d_fs_in;
//double d_preamble_duration_seconds;
// navigation message vars