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Avoid extrapolation

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This commit is contained in:
Antonio Ramos
2018-02-22 11:14:57 +01:00
parent df5f51ba91
commit ca9a551a86
2 changed files with 40 additions and 68 deletions
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83
src/algorithms/observables/gnuradio_blocks/hybrid_observables_cc.cc
View File

@@ -58,7 +58,6 @@ hybrid_observables_cc::hybrid_observables_cc(unsigned int nchannels_in, unsigned
{
set_max_noutput_items(1);
d_dump = dump;
set_T_rx_s = false;
d_nchannels = nchannels_out;
d_dump_filename = dump_filename;
d_dump_filename_in = d_dump_filename;
@@ -376,7 +375,7 @@ void hybrid_observables_cc::clean_history(std::deque<Gnss_Synchro>& data)
}
}
std::pair<Gnss_Synchro, Gnss_Synchro> hybrid_observables_cc::find_closest(std::deque<Gnss_Synchro>& data)
std::pair<Gnss_Synchro, Gnss_Synchro> hybrid_observables_cc::find_closest(std::deque<Gnss_Synchro>& data, const double& ti)
{
std::pair<Gnss_Synchro, Gnss_Synchro> result;
unsigned int index = 0;
@@ -385,7 +384,7 @@ std::pair<Gnss_Synchro, Gnss_Synchro> hybrid_observables_cc::find_closest(std::d
unsigned int aux = 0;
for(it = data.begin(); it != data.end(); it++)
{
double instant_delta = std::fabs(T_rx_s - it->RX_time);
double instant_delta = std::fabs(ti - it->RX_time);
if(instant_delta < delta_t)
{
delta_t = instant_delta;
@@ -393,50 +392,31 @@ std::pair<Gnss_Synchro, Gnss_Synchro> hybrid_observables_cc::find_closest(std::d
}
aux++;
}
try
delta_t = ti - data.at(index).RX_time;
if( (index == 0) or (index == (data.size() - 1)) )
{
delta_t = T_rx_s - data.at(index).RX_time;
if(index == 0)
{
result.first = data.at(1);
result.second = data.at(0);
Gnss_Synchro invalid_data;
invalid_data.Flag_valid_pseudorange = false;
result.first = invalid_data;
result.second = invalid_data;
}
else if((index == (data.size() - 1)) or (delta_t < 0.0))
else if(delta_t < 0.0)
{
result.first = data.at(index);
result.first.Flag_valid_pseudorange = true;
result.second = data.at(index - 1);
result.second.Flag_valid_pseudorange = true;
}
else
{
result.first = data.at(index + 1);
result.first.Flag_valid_pseudorange = true;
result.second = data.at(index);
}
}
catch(const std::exception& e)
{
result.first = Gnss_Synchro();
result.second = Gnss_Synchro();
LOG(WARNING) << "Exception computing observables " << e.what();
result.second.Flag_valid_pseudorange = true;
}
return result;
}
double hybrid_observables_cc::find_min_RX_time()
{
if(d_num_valid_channels == 0) { return 0.0; }
std::vector<std::deque<Gnss_Synchro>>::iterator it = d_gnss_synchro_history.begin();
double result = std::numeric_limits<double>::max();
for(unsigned int i = 0; i < d_nchannels; i++)
{
if(valid_channels[i])
{
if(it->front().RX_time < result) { result = it->front().RX_time; }
}
it++;
}
return(floor(result * 1000.0) / 1000.0);
}
void hybrid_observables_cc::correct_TOW_and_compute_prange(std::vector<Gnss_Synchro>& data)
{
@@ -466,16 +446,15 @@ int hybrid_observables_cc::general_work(int noutput_items __attribute__((unused)
int total_input_items = 0;
for(i = 0; i < d_nchannels; i++) { total_input_items += ninput_items[i]; }
consume(d_nchannels, 1);
T_rx_s += T_rx_step_s;
//////////////////////////////////////////////////////////////////////////
if((total_input_items == 0) and (d_num_valid_channels == 0))
{
return 0;
}
if(set_T_rx_s) { T_rx_s += T_rx_step_s; }
//////////////////////////////////////////////////////////////////////////
std::vector<std::deque<Gnss_Synchro>>::iterator it;
if (total_input_items > 0)
{
@@ -498,7 +477,7 @@ int hybrid_observables_cc::general_work(int noutput_items __attribute__((unused)
{
if(it->front().PRN != it->back().PRN) { it->clear(); __dump = false; }
}
if(d_dump && __dump)
if(d_dump and __dump)
{
// MULTIPLEXED FILE RECORDING - Record results to file
try
@@ -529,17 +508,7 @@ int hybrid_observables_cc::general_work(int noutput_items __attribute__((unused)
}
d_num_valid_channels = valid_channels.count();
// Check if there is any valid channel after reading the new incoming Gnss_Synchro data
if(d_num_valid_channels == 0)
{
set_T_rx_s = false;
return 0;
}
if(!set_T_rx_s) //Find the lowest RX_time among the valid observables in the history
{
T_rx_s = find_min_RX_time();
set_T_rx_s = true;
}
if(d_num_valid_channels == 0) { return 0; }
for(i = 0; i < d_nchannels; i++) //Discard observables with T_rx higher than the threshold
{
@@ -552,11 +521,8 @@ int hybrid_observables_cc::general_work(int noutput_items __attribute__((unused)
// Check if there is any valid channel after computing the time distance between the Gnss_Synchro data and the receiver time
d_num_valid_channels = valid_channels.count();
if(d_num_valid_channels == 0)
{
set_T_rx_s = false;
return 0;
}
double T_rx_s_out = T_rx_s - (max_delta / 2.0);
if((d_num_valid_channels == 0) or (T_rx_s_out < 0.0)) { return 0; }
std::vector<Gnss_Synchro> epoch_data;
i = 0;
@@ -564,15 +530,18 @@ int hybrid_observables_cc::general_work(int noutput_items __attribute__((unused)
{
if(valid_channels[i])
{
std::pair<Gnss_Synchro, Gnss_Synchro> gnss_pair = find_closest(*it);
std::pair<Gnss_Synchro, Gnss_Synchro> gnss_pair = find_closest(*it, T_rx_s_out);
Gnss_Synchro interpolated_gnss_synchro = gnss_pair.second;
interpolated_gnss_synchro.Carrier_Doppler_hz = interpolate_data(gnss_pair, T_rx_s, 0);
interpolated_gnss_synchro.Carrier_phase_rads = interpolate_data(gnss_pair, T_rx_s, 1);
interpolated_gnss_synchro.TOW_at_current_symbol_s = interpolate_data(gnss_pair, T_rx_s, 2);
if(interpolated_gnss_synchro.Flag_valid_pseudorange)
{
interpolated_gnss_synchro.Carrier_Doppler_hz = interpolate_data(gnss_pair, T_rx_s_out, 0);
interpolated_gnss_synchro.Carrier_phase_rads = interpolate_data(gnss_pair, T_rx_s_out, 1);
interpolated_gnss_synchro.TOW_at_current_symbol_s = interpolate_data(gnss_pair, T_rx_s_out, 2);
epoch_data.push_back(interpolated_gnss_synchro);
}
else { valid_channels[i] = false; }
}
i++;
}

9
src/algorithms/observables/gnuradio_blocks/hybrid_observables_cc.h
View File

@@ -68,8 +68,7 @@ private:
void clean_history(std::deque<Gnss_Synchro>& data);
double compute_T_rx_s(const Gnss_Synchro& a);
double interpolate_data(const std::pair<Gnss_Synchro, Gnss_Synchro>& a, const double& ti, int parameter);
double find_min_RX_time();
std::pair<Gnss_Synchro, Gnss_Synchro> find_closest(std::deque<Gnss_Synchro>& data);
std::pair<Gnss_Synchro, Gnss_Synchro> find_closest(std::deque<Gnss_Synchro>& data, const double& ti);
void correct_TOW_and_compute_prange(std::vector<Gnss_Synchro>& data);
//Tracking observable history
@@ -79,7 +78,6 @@ private:
double T_rx_step_s;
double max_delta;
bool d_dump;
bool set_T_rx_s;
unsigned int d_nchannels;
unsigned int d_num_valid_channels;
std::string d_dump_filename;
@@ -87,6 +85,11 @@ private:
std::ofstream d_dump_file;
std::ofstream d_dump_in;
std::string text_red = "\033[31m";
std::string text_green = "\033[32m";
std::string text_reset = "\033[0m";
int save_matfile();
};