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Added J.Arribas contributions: PVT with basic least squares and rinex 2.1 output is now enabled, tracking channels now estimate the CN0 and performs a basic carrier lock detector and returns to acquisition if the tracking loss the lock.

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git-svn-id: https://svn.code.sf.net/p/gnss-sdr/code/trunk@75 64b25241-fba3-4117-9849-534c7e92360d
This commit is contained in:
Javier Arribas
2011-10-28 15:01:46 +00:00
parent 0069bef236
commit 1040e6865d
25 changed files with 961 additions and 373 deletions
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src/algorithms/telemetry_decoder/gnuradio_blocks/gps_l1_ca_telemetry_decoder_cc.cc
+14 -12
View File
@@ -47,7 +47,7 @@ void gps_l1_ca_telemetry_decoder_cc::forecast (int noutput_items,
gps_l1_ca_telemetry_decoder_cc::gps_l1_ca_telemetry_decoder_cc(unsigned int satellite, long if_freq, long fs_in, unsigned
int vector_length, gr_msg_queue_sptr queue, bool dump) :
gr_block ("gps_navigation_cc", gr_make_io_signature (3, 3, sizeof(float)),
gr_block ("gps_navigation_cc", gr_make_io_signature (5, 5, sizeof(float)),
gr_make_io_signature(1, 1, sizeof(gnss_synchro))) {
// initialize internal vars
d_queue = queue;
@@ -106,10 +106,6 @@ int gps_l1_ca_telemetry_decoder_cc::general_work (int noutput_items, gr_vector_i
d_sample_counter++; //count for the processed samples
const float **in = (const float **) &input_items[0]; //Get the input samples pointer
//std::cout<<"CH1="<<in[0][0]; // Q
//std::cout<<"CH2="<<in[1][0]; // I
//std::cout<<"CH3="<<in[2][0]; // Delay
//std::cout<<"N_input_streams="<<ninput_items.size();
// TODO Optimize me!
//******* preamble correlation ********
@@ -123,13 +119,13 @@ int gps_l1_ca_telemetry_decoder_cc::general_work (int noutput_items, gr_vector_i
}
//******* frame sync ******************
if (abs(corr_value)>=153){
if (abs(corr_value)>=160){
//TODO: Rewrite with state machine
if (d_stat==0)
{
d_GPS_FSM.Event_gps_word_preamble();
d_preamble_index=d_sample_counter;//record the preamble sample stamp
std::cout<<"Pre-detection"<<std::endl;
std::cout<<"Pre-detection SAT "<<this->d_satellite+1<<std::endl;
d_symbol_accumulator=0; //sync the symbol to bits integrator
d_symbol_accumulator_counter=0;
d_frame_bit_index=8;
@@ -140,15 +136,17 @@ int gps_l1_ca_telemetry_decoder_cc::general_work (int noutput_items, gr_vector_i
if (abs(preamble_diff-6000)<1)
{
d_GPS_FSM.Event_gps_word_preamble();
d_preamble_index=d_sample_counter;//record the preamble sample stamp
d_preamble_index=d_sample_counter;//record the preamble sample stamp (t_P)
d_preamble_phase=in[2][0]; //record the PRN start sample index associated to the preamble
if (!d_flag_frame_sync){
d_flag_frame_sync=true;
std::cout<<" Frame sync with phase "<<in[2][0]<<std::endl;
std::cout<<" Frame sync SAT "<<this->d_satellite+1<<" with preamble start at "<<in[2][0]<<" [ms]"<<std::endl;
}
}else
{
if (preamble_diff>7000){
std::cout<<"lost of frame sync"<<std::endl;
std::cout<<"lost of frame sync SAT "<<this->d_satellite+1<<std::endl;
d_stat=0; //lost of frame sync
d_flag_frame_sync=false;
}
@@ -156,6 +154,8 @@ int gps_l1_ca_telemetry_decoder_cc::general_work (int noutput_items, gr_vector_i
}
}
//******* code error accumulator *****
//d_preamble_phase-=in[3][0];
//******* SYMBOL TO BIT *******
d_symbol_accumulator+=in[1][d_samples_per_bit*8-1]; // accumulate the input value in d_symbol_accumulator
@@ -194,6 +194,7 @@ int gps_l1_ca_telemetry_decoder_cc::general_work (int noutput_items, gr_vector_i
}
if (gps_word_parityCheck(d_GPS_frame_4bytes)) {
memcpy(&d_GPS_FSM.d_GPS_frame_4bytes,&d_GPS_frame_4bytes,sizeof(char)*4);
d_GPS_FSM.d_preamble_time_ms=d_preamble_phase;
d_GPS_FSM.Event_gps_word_valid();
d_flag_parity=true;
}else{
@@ -213,8 +214,9 @@ int gps_l1_ca_telemetry_decoder_cc::general_work (int noutput_items, gr_vector_i
if ((d_sample_counter%NAVIGATION_OUTPUT_RATE_MS)==0)
{
gps_synchro.valid_word=(d_flag_frame_sync==true and d_flag_parity==true);
gps_synchro.last_preamble_index=d_preamble_index;
gps_synchro.prn_delay=in[2][0];
//gps_synchro.preamble_delay_ms=(float)d_preamble_index;
gps_synchro.preamble_delay_ms=(float)d_preamble_index;
gps_synchro.prn_delay_ms=in[3][0];
gps_synchro.satellite_PRN=d_satellite+1;
gps_synchro.channel_ID=d_channel;
*out[0]=gps_synchro;
src/algorithms/telemetry_decoder/gnuradio_blocks/gps_l1_ca_telemetry_decoder_cc.h
+2
View File
@@ -76,6 +76,8 @@ private:
int d_satellite;
int d_channel;
float d_preamble_phase;
std::string d_dump_filename;
std::ofstream d_dump_file;