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Code Issues Releases Wiki Activity

Minor changes

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This commit is contained in:
Antonio Ramos
2017-12-11 12:17:01 +01:00
parent 8b5f7097b3
commit 26a521907a
21 changed files with 285 additions and 238 deletions
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4
src/algorithms/telemetry_decoder/adapters/gps_l5_telemetry_decoder.cc
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@@ -34,10 +34,6 @@
#include <gnuradio/io_signature.h>
#include <glog/logging.h>
#include "concurrent_queue.h"
#include "gps_cnav_ephemeris.h"
#include "gps_almanac.h"
#include "gps_cnav_iono.h"
#include "gps_cnav_utc_model.h"
#include "configuration_interface.h"

1
src/algorithms/telemetry_decoder/adapters/gps_l5_telemetry_decoder.h
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@@ -36,6 +36,7 @@
#include <string>
#include "telemetry_decoder_interface.h"
#include "gps_l5_telemetry_decoder_cc.h"
#include "gnss_satellite.h"
class ConfigurationInterface;

75
src/algorithms/telemetry_decoder/gnuradio_blocks/gps_l5_telemetry_decoder_cc.cc
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@@ -37,6 +37,8 @@
#include <boost/lexical_cast.hpp>
#include "gnss_synchro.h"
#include "gps_l5_telemetry_decoder_cc.h"
#include "gps_cnav_ephemeris.h"
#include "gps_cnav_iono.h"
using google::LogMessage;
@@ -70,6 +72,19 @@ gps_l5_telemetry_decoder_cc::gps_l5_telemetry_decoder_cc(
//initialize the CNAV frame decoder (libswiftcnav)
cnav_msg_decoder_init(&d_cnav_decoder);
for(int aux = 0; aux < GPS_L5_NH_CODE_LENGTH; aux++)
{
if(GPS_L5_NH_CODE[aux] == 0)
{
bits_NH[aux] = -1.0;
}
else
{
bits_NH[aux] = 1.0;
}
}
sync_NH = false;
new_sym = false;
}
@@ -96,26 +111,58 @@ int gps_l5_telemetry_decoder_cc::general_work (int noutput_items __attribute__((
Gnss_Synchro *out = reinterpret_cast<Gnss_Synchro *>(output_items[0]); // Get the output buffer pointer
const Gnss_Synchro *in = reinterpret_cast<const Gnss_Synchro *>(input_items[0]); // Get the input buffer pointer
// UPDATE GNSS SYNCHRO DATA
Gnss_Synchro current_synchro_data; //structure to save the synchronization information and send the output object to the next block
//1. Copy the current tracking output
current_synchro_data = in[0];
consume_each(1); //one by one
sym_hist.push_back(in[0].Prompt_I);
double symbol_value = 0.0;
if(sym_hist.size() == GPS_L5_NH_CODE_LENGTH)
{
std::deque<double>::iterator it;
int corr_NH = 0;
it = sym_hist.begin();
for(int i = 0; i < GPS_L5_NH_CODE_LENGTH; i++)
{
if((bits_NH[i] * (*it)) > 0.0){corr_NH += 1;}
else{corr_NH -= 1;}
it++;
}
if(abs(corr_NH) == GPS_L5_NH_CODE_LENGTH){sync_NH = true;}
else
{
sym_hist.pop_front();
sync_NH = false;
}
if (sync_NH)
{
new_sym = true;
for(it = sym_hist.begin(); it != sym_hist.end(); it++)
{
symbol_value += (*it);
}
sym_hist.clear();
}
}
bool flag_new_cnav_frame = false;
cnav_msg_t msg;
u32 delay = 0;
//add the symbol to the decoder
u8 symbol_clip = static_cast<u8>(in[0].Prompt_I > 0) * 255;
flag_new_cnav_frame = cnav_msg_decoder_add_symbol(&d_cnav_decoder, symbol_clip, &msg, &delay);
consume_each(1); //one by one
// UPDATE GNSS SYNCHRO DATA
Gnss_Synchro current_synchro_data; //structure to save the synchronization information and send the output object to the next block
//1. Copy the current tracking output
current_synchro_data = in[0];
if(new_sym)
{
u8 symbol_clip = static_cast<u8>(symbol_value > 0.0) * 255;
flag_new_cnav_frame = cnav_msg_decoder_add_symbol(&d_cnav_decoder, symbol_clip, &msg, &delay);
new_sym = false;
}
//2. Add the telemetry decoder information
//check if new CNAV frame is available
if (flag_new_cnav_frame == true)
{
std::cout << "NEW CNAV FRAME" << std::endl;
std::bitset<GPS_L5_CNAV_DATA_PAGE_BITS> raw_bits;
//Expand packet bits to bitsets. Notice the reverse order of the bits sequence, required by the CNAV message decoder
for (u32 i = 0; i < GPS_L5_CNAV_DATA_PAGE_BITS ; i++)
@@ -169,12 +216,6 @@ int gps_l5_telemetry_decoder_cc::general_work (int noutput_items __attribute__((
current_synchro_data.TOW_at_current_symbol_s = d_TOW_at_current_symbol;
current_synchro_data.Flag_valid_word = d_flag_valid_word;
// if (flag_PLL_180_deg_phase_locked == true)
// {
// //correct the accumulated phase for the Costas loop phase shift, if required
// current_synchro_data.Carrier_phase_rads += GPS_PI;
// }
if(d_dump == true)
{
// MULTIPLEXED FILE RECORDING - Record results to file

10
src/algorithms/telemetry_decoder/gnuradio_blocks/gps_l5_telemetry_decoder_cc.h
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@@ -31,17 +31,15 @@
#ifndef GNSS_SDR_GPS_L5_TELEMETRY_DECODER_CC_H
#define GNSS_SDR_GPS_L5_TELEMETRY_DECODER_CC_H
#include <algorithm> // for copy
#include <algorithm>
#include <deque>
#include <fstream>
#include <string>
#include <utility> // for pair
#include <utility>
#include <vector>
#include <gnuradio/block.h>
#include "gnss_satellite.h"
#include "gps_cnav_navigation_message.h"
#include "gps_cnav_ephemeris.h"
#include "gps_cnav_iono.h"
#include "concurrent_queue.h"
extern "C" {
@@ -99,6 +97,10 @@ private:
bool d_flag_valid_word;
Gps_CNAV_Navigation_Message d_CNAV_Message;
double bits_NH[GPS_L5_NH_CODE_LENGTH];
std::deque<double> sym_hist;
bool sync_NH;
bool new_sym;
};

2
src/algorithms/telemetry_decoder/libs/libswiftcnav/cnav_msg.c
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@@ -49,11 +49,9 @@
*/
/** Viterbi decoder reversed polynomial A */
#define GPS_L2C_V27_POLY_A (0x4F) /* 0b01001111 - reversed 0171*/
#define GPS_L5_V27_POLY_A (0x4F) /* 0b01001111 - reversed 0171*/
/** Viterbi decoder reversed polynomial B */
#define GPS_L2C_V27_POLY_B (0x6D) /* 0b01101101 - reversed 0133 */
#define GPS_L5_V27_POLY_B (0x6D) /* 0b01101101 - reversed 0133 */
/*
* GPS L2C message constants.
*/

34
src/algorithms/telemetry_decoder/libs/libswiftcnav/cnav_msg.h
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@@ -49,16 +49,12 @@
/** Size of the Viterbi decoder history. */
#define GPS_L2_V27_HISTORY_LENGTH_BITS 64
#define GPS_L5_V27_HISTORY_LENGTH_BITS 64
/** Bits to accumulate before decoding starts. */
#define GPS_L2C_V27_INIT_BITS (32)
#define GPS_L5_V27_INIT_BITS (32)
/** Bits to decode at a time. */
#define GPS_L2C_V27_DECODE_BITS (32)
#define GPS_L5_V27_DECODE_BITS (32)
/** Bits in decoder tail. We ignore them. */
#define GPS_L2C_V27_DELAY_BITS (32)
#define GPS_L5_V27_DELAY_BITS (32)
/**
* GPS CNAV message container.
*
@@ -73,15 +69,6 @@ typedef struct
u8 raw_msg[GPS_L2C_V27_DECODE_BITS + GPS_L2C_V27_DELAY_BITS]; /**< RAW MSG for GNSS-SDR */
} cnav_msg_t;
typedef struct
{
u8 prn; /**< SV PRN. 0..31 */
u8 msg_id; /**< Message id. 0..31 */
u32 tow; /**< GPS ToW in 6-second units. Multiply to 6 to get seconds. */
bool alert; /**< CNAV message alert flag */
u8 raw_msg[GPS_L5_V27_DECODE_BITS + GPS_L5_V27_DELAY_BITS]; /**< RAW MSG for GNSS-SDR */
} cnav_L5_msg_t;
/**
* GPS CNAV decoder component.
* This component controls symbol decoding string.
@@ -109,27 +96,6 @@ typedef struct {
* do not produce output. */
} cnav_v27_part_t;
typedef struct {
v27_t dec; /**< Viterbi block decoder object */
v27_decision_t decisions[GPS_L5_V27_HISTORY_LENGTH_BITS];
/**< Decision graph */
unsigned char symbols[(GPS_L5_V27_INIT_BITS + GPS_L5_V27_DECODE_BITS) * 2];
/**< Symbol buffer */
size_t n_symbols; /**< Count of symbols in the symbol buffer */
unsigned char decoded[GPS_L5_V27_DECODE_BITS + GPS_L5_V27_DELAY_BITS];
/**< Decode buffer */
size_t n_decoded; /**< Number of bits in the decode buffer */
bool preamble_seen; /**< When true, the decode buffer is aligned on
* preamble. */
bool invert; /**< When true, indicates the bits are inverted */
bool message_lock; /**< When true, indicates the message boundary
* is found. */
bool crc_ok; /**< Flag that the last message had good CRC */
size_t n_crc_fail; /**< Counter for CRC failures */
bool init; /**< Initial state flag. When true, initial bits
* do not produce output. */
} cnav_L5_v27_part_t;
/**
* GPS CNAV message lock and decoder object.
*