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Merge pull request #155 from antonioramosdet/fine_tune_buffer_size_and_latency

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Fine tune buffer parameters
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Javier Arribas 2018-04-12 11:22:14 +02:00 committed by GitHub
commit ee732e09d4
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GPG Key ID: 4AEE18F83AFDEB23
2 changed files with 26 additions and 27 deletions
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51
src/algorithms/observables/gnuradio_blocks/hybrid_observables_cc.cc
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@ -63,8 +63,8 @@ hybrid_observables_cc::hybrid_observables_cc(unsigned int nchannels_in,
d_dump_filename = dump_filename;
T_rx_s = 0.0;
T_rx_step_s = 0.001; // 1 ms
max_delta = 3.5; // 3.5 s
d_latency = 0.08; // 80 ms
max_delta = 1.5; // 1.5 s
d_latency = 0.175; // 175 ms
valid_channels.resize(d_nchannels, false);
d_num_valid_channels = 0;
d_gnss_synchro_history = new Gnss_circular_deque<Gnss_Synchro>(static_cast<unsigned int>(max_delta * 1000.0), d_nchannels);
@ -306,21 +306,18 @@ bool hybrid_observables_cc::interpolate_data(Gnss_Synchro &out, const unsigned i
{
return false;
}
std::pair<unsigned int, unsigned int> ind = find_interp_elements(ch, ti);
find_interp_elements(ch, ti);
//Linear interpolation: y(t) = y(t1) + (y(t2) - y(t1)) * (t - t1) / (t2 - t1)
// CARRIER PHASE INTERPOLATION
out.Carrier_phase_rads = d_gnss_synchro_history->at(ch, ind.first).Carrier_phase_rads + (d_gnss_synchro_history->at(ch, ind.second).Carrier_phase_rads - d_gnss_synchro_history->at(ch, ind.first).Carrier_phase_rads) * (ti - d_gnss_synchro_history->at(ch, ind.first).RX_time) / (d_gnss_synchro_history->at(ch, ind.second).RX_time - d_gnss_synchro_history->at(ch, ind.first).RX_time);
out.Carrier_phase_rads = d_gnss_synchro_history->at(ch, 0).Carrier_phase_rads + (d_gnss_synchro_history->at(ch, 1).Carrier_phase_rads - d_gnss_synchro_history->at(ch, 0).Carrier_phase_rads) * (ti - d_gnss_synchro_history->at(ch, 0).RX_time) / (d_gnss_synchro_history->at(ch, 1).RX_time - d_gnss_synchro_history->at(ch, 0).RX_time);
// CARRIER DOPPLER INTERPOLATION
out.Carrier_Doppler_hz = d_gnss_synchro_history->at(ch, ind.first).Carrier_Doppler_hz + (d_gnss_synchro_history->at(ch, ind.second).Carrier_Doppler_hz - d_gnss_synchro_history->at(ch, ind.first).Carrier_Doppler_hz) * (ti - d_gnss_synchro_history->at(ch, ind.first).RX_time) / (d_gnss_synchro_history->at(ch, ind.second).RX_time - d_gnss_synchro_history->at(ch, ind.first).RX_time);
out.Carrier_Doppler_hz = d_gnss_synchro_history->at(ch, 0).Carrier_Doppler_hz + (d_gnss_synchro_history->at(ch, 1).Carrier_Doppler_hz - d_gnss_synchro_history->at(ch, 0).Carrier_Doppler_hz) * (ti - d_gnss_synchro_history->at(ch, 0).RX_time) / (d_gnss_synchro_history->at(ch, 1).RX_time - d_gnss_synchro_history->at(ch, 0).RX_time);
// TOW INTERPOLATION
out.TOW_at_current_symbol_s = d_gnss_synchro_history->at(ch, ind.first).TOW_at_current_symbol_s + (d_gnss_synchro_history->at(ch, ind.second).TOW_at_current_symbol_s - d_gnss_synchro_history->at(ch, ind.first).TOW_at_current_symbol_s) * (ti - d_gnss_synchro_history->at(ch, ind.first).RX_time) / (d_gnss_synchro_history->at(ch, ind.second).RX_time - d_gnss_synchro_history->at(ch, ind.first).RX_time);
out.TOW_at_current_symbol_s = d_gnss_synchro_history->at(ch, 0).TOW_at_current_symbol_s + (d_gnss_synchro_history->at(ch, 1).TOW_at_current_symbol_s - d_gnss_synchro_history->at(ch, 0).TOW_at_current_symbol_s) * (ti - d_gnss_synchro_history->at(ch, 0).RX_time) / (d_gnss_synchro_history->at(ch, 1).RX_time - d_gnss_synchro_history->at(ch, 0).RX_time);
return true;
}
@ -338,38 +335,40 @@ double hybrid_observables_cc::compute_T_rx_s(const Gnss_Synchro &a)
}
}
std::pair<unsigned int, unsigned int> hybrid_observables_cc::find_interp_elements(const unsigned int &ch, const double &ti)
void hybrid_observables_cc::find_interp_elements(const unsigned int &ch, const double &ti)
{
unsigned int closest = 0;
double dif = std::numeric_limits<double>::max();
double dt = 0.0;
for (unsigned int i = 0; i < d_gnss_synchro_history->size(ch); i++)
{
dt = ti - d_gnss_synchro_history->at(ch, i).RX_time;
if (dt < dif and dt > 0.0)
dt = std::fabs(ti - d_gnss_synchro_history->at(ch, i).RX_time);
if (dt < dif)
{
dif = dt;
closest = i;
dif = dt;
}
else
{
break;
}
}
unsigned int index1;
unsigned int index2;
if (closest == 0)
if (ti > d_gnss_synchro_history->at(ch, closest).RX_time)
{
index1 = 0;
index2 = 1;
}
else if (closest == (d_gnss_synchro_history->size(ch) - 1))
{
index1 = d_gnss_synchro_history->size(ch) - 2;
index2 = d_gnss_synchro_history->size(ch) - 1;
while (closest > 0)
{
d_gnss_synchro_history->pop_front(ch);
closest--;
}
}
else
{
index1 = closest;
index2 = closest + 1;
while (closest > 1)
{
d_gnss_synchro_history->pop_front(ch);
closest--;
}
}
return std::pair<unsigned int, unsigned int>(index1, index2);
}

2
src/algorithms/observables/gnuradio_blocks/hybrid_observables_cc.h
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@ -68,7 +68,7 @@ private:
void clean_history(unsigned int pos);
double compute_T_rx_s(const Gnss_Synchro& a);
bool interpolate_data(Gnss_Synchro& out, const unsigned int& ch, const double& ti);
std::pair<unsigned int, unsigned int> find_interp_elements(const unsigned int& ch, const double& ti);
void find_interp_elements(const unsigned int& ch, const double& ti);
void correct_TOW_and_compute_prange(std::vector<Gnss_Synchro>& data);
int save_matfile();