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reverting wrong commit

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This commit is contained in:
Carles Fernandez
2016-03-09 15:56:07 +01:00
parent 59011a7772
commit 1e9a9d1a55
10 changed files with 325 additions and 140 deletions
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74
src/algorithms/telemetry_decoder/gnuradio_blocks/gps_l1_ca_telemetry_decoder_cc.cc
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@@ -38,6 +38,7 @@
#include <iostream>
#include <boost/lexical_cast.hpp>
#include <gnuradio/io_signature.h>
#include <pmt/pmt.h>
#include <glog/logging.h>
#include "control_message_factory.h"
#include "gnss_synchro.h"
@@ -78,6 +79,9 @@ gps_l1_ca_telemetry_decoder_cc::gps_l1_ca_telemetry_decoder_cc(
gr::block("gps_navigation_cc", gr::io_signature::make(1, 1, sizeof(Gnss_Synchro)),
gr::io_signature::make(1, 1, sizeof(Gnss_Synchro)))
{
// create asynchronous message ports
this->message_port_register_out(pmt::mp("preamble_index"));
// initialize internal vars
d_queue = queue;
d_dump = dump;
@@ -178,6 +182,8 @@ int gps_l1_ca_telemetry_decoder_cc::general_work (int noutput_items, gr_vector_i
const Gnss_Synchro **in = (const Gnss_Synchro **) &input_items[0]; //Get the input samples pointer
// TODO Optimize me!
if (in[0][d_samples_per_bit*8 - 1].symbol_integration_enabled==false)
{
//******* preamble correlation ********
for (unsigned int i = 0; i < d_samples_per_bit*8; i++)
{
@@ -190,20 +196,37 @@ int gps_l1_ca_telemetry_decoder_cc::general_work (int noutput_items, gr_vector_i
corr_value += d_preambles_symbols[i];
}
}
}else{
//******* preamble correlation ********
for (unsigned int i = 0; i < d_samples_per_bit*8; i++)
{
if (in[0][i].Flag_valid_symbol_output==true)
{
if (in[0][i].Prompt_I < 0) // symbols clipping
{
corr_value -= d_preambles_symbols[i]*d_samples_per_bit;
}
else
{
corr_value += d_preambles_symbols[i]*d_samples_per_bit;
}
}
}
}
d_flag_preamble = false;
//******* frame sync ******************
if (abs(corr_value) >= 160)
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
LOG(INFO) << "Preamble detection for SAT " << this->d_satellite;
DLOG(INFO) << "Preamble detection for SAT " << this->d_satellite;
d_symbol_accumulator = 0; //sync the symbol to bits integrator
d_symbol_accumulator_counter = 0;
d_frame_bit_index = 8;
d_frame_bit_index = 7;
d_stat = 1; // enter into frame pre-detection status
}
else if (d_stat == 1) //check 6 seconds of preamble separation
@@ -215,20 +238,24 @@ int gps_l1_ca_telemetry_decoder_cc::general_work (int noutput_items, gr_vector_i
d_flag_preamble = true;
d_preamble_index = d_sample_counter; //record the preamble sample stamp (t_P)
d_preamble_time_seconds = in[0][0].Tracking_timestamp_secs;// - d_preamble_duration_seconds; //record the PRN start sample index associated to the preamble
d_frame_bit_index = 7;
if (!d_flag_frame_sync)
{
//send asynchronous message to tracking to inform of frame sync and extend correlation time
pmt::pmt_t value = pmt::from_long(d_preamble_index-1);
this->message_port_pub(pmt::mp("preamble_index"),value);
d_flag_frame_sync = true;
if (corr_value < 0)
{
flag_PLL_180_deg_phase_locked = true; //PLL is locked to opposite phase!
LOG(INFO) << " PLL in opposite phase for Sat "<< this->d_satellite.get_PRN();
DLOG(INFO) << " PLL in opposite phase for Sat "<< this->d_satellite.get_PRN();
}
else
{
flag_PLL_180_deg_phase_locked = false;
}
LOG(INFO) << " Frame sync SAT " << this->d_satellite << " with preamble start at " << d_preamble_time_seconds << " [s]";
DLOG(INFO) << " Frame sync SAT " << this->d_satellite << " with preamble start at " << d_preamble_time_seconds << " [s]";
}
}
}
@@ -240,7 +267,7 @@ int gps_l1_ca_telemetry_decoder_cc::general_work (int noutput_items, gr_vector_i
preamble_diff = d_sample_counter - d_preamble_index;
if (preamble_diff > 6001)
{
LOG(INFO) << "Lost of frame sync SAT " << this->d_satellite << " preamble_diff= " << preamble_diff;
DLOG(INFO) << "Lost of frame sync SAT " << this->d_satellite << " preamble_diff= " << preamble_diff;
d_stat = 0; //lost of frame sync
d_flag_frame_sync = false;
flag_TOW_set = false;
@@ -249,16 +276,29 @@ int gps_l1_ca_telemetry_decoder_cc::general_work (int noutput_items, gr_vector_i
}
//******* SYMBOL TO BIT *******
d_symbol_accumulator += in[0][d_samples_per_bit*8 - 1].Prompt_I; // accumulate the input value in d_symbol_accumulator
d_symbol_accumulator_counter++;
if (d_symbol_accumulator_counter == 20)
if (in[0][d_samples_per_bit*8 - 1].Flag_valid_symbol_output==true)
{
if (in[0][d_samples_per_bit*8 - 1].symbol_integration_enabled==true)
{
// extended correlation to bit period is enabled in tracking!
// 1 symbol = 1 bit
d_symbol_accumulator = in[0][d_samples_per_bit*8 - 1].Prompt_I; // accumulate the input value in d_symbol_accumulator
d_symbol_accumulator_counter=20;
}else{
// 20 symbols = 1 bit: do symbols integration in telemetry decoder
d_symbol_accumulator += in[0][d_samples_per_bit*8 - 1].Prompt_I; // accumulate the input value in d_symbol_accumulator
d_symbol_accumulator_counter++;
}
}
if (d_symbol_accumulator_counter == 20 )
{
if (d_symbol_accumulator > 0)
{ //symbol to bit
d_GPS_frame_4bytes += 1; //insert the telemetry bit in LSB
}
d_symbol_accumulator = 0;
d_symbol_accumulator_counter = 0;
if (d_symbol_accumulator > 0)
{ //symbol to bit
d_GPS_frame_4bytes += 1; //insert the telemetry bit in LSB
}
d_symbol_accumulator = 0;
d_symbol_accumulator_counter = 0;
//******* bits to words ******
d_frame_bit_index++;
if (d_frame_bit_index == 30)
@@ -302,6 +342,8 @@ int gps_l1_ca_telemetry_decoder_cc::general_work (int noutput_items, gr_vector_i
{
d_GPS_frame_4bytes <<= 1; //shift 1 bit left the telemetry word
}
}
// output the frame
consume_each(1); //one by one