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Removed boost timer from clock_offset_control to avoid race conditions. 

The time is now tracked by the receiver based on samples count and send through the 'measurements' interface to the clock_offset_control.
clock_offset_control takes time into account during fcch_search.
This commit is contained in:
ptrkrysik 2015-04-04 14:01:52 +02:00
parent f8c7e83298
commit 32c2116d88
4 changed files with 38 additions and 13 deletions
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31
lib/receiver/clock_offset_control_impl.cc
View File

@ -1,3 +1,4 @@
/* -*- c++ -*- */
/*
* @file
@ -45,8 +46,7 @@ clock_offset_control::make(float fc)
clock_offset_control_impl::clock_offset_control_impl(float fc)
: gr::block("clock_offset_control",
gr::io_signature::make(0, 0, 0),
gr::io_signature::make(0, 0, 0)),
d_timer(d_io_service)
gr::io_signature::make(0, 0, 0))
{
message_port_register_in(pmt::mp("measurements"));
@ -60,8 +60,9 @@ clock_offset_control_impl::clock_offset_control_impl(float fc)
d_first_measurement = true;
d_counter = 0;
d_last_state = "";
d_timer.async_wait(boost::bind(&clock_offset_control_impl::timed_reset, this));
d_current_time = 0;
d_last_fcch_time = 0;
d_first_time = true;
}
/*
@ -81,6 +82,21 @@ void clock_offset_control_impl::process_measurement(pmt::pmt_t msg)
if(pmt::is_tuple(msg))
{
std::string key = pmt::symbol_to_string(pmt::tuple_ref(msg,0));
if(key == "current_time")
{
d_current_time = pmt::to_double(pmt::tuple_ref(msg,1));
if(d_first_time==true)
{
d_last_fcch_time = d_current_time;
d_first_time = false;
}
else
if((d_current_time - d_last_fcch_time) > 0.5 && d_last_state == "fcch_search")
{
timed_reset();
}
}
else
if(key == "freq_offset")
{
float freq_offset = pmt::to_double(pmt::tuple_ref(msg,1));
@ -89,7 +105,7 @@ void clock_offset_control_impl::process_measurement(pmt::pmt_t msg)
d_last_state = state;
if(abs(ppm) > 100) //safeguard against flawed measurements
{
ppm = 0; //!!! do poprawki ten warunek
ppm=0;
reset();
}
@ -97,13 +113,12 @@ void clock_offset_control_impl::process_measurement(pmt::pmt_t msg)
{
pmt::pmt_t msg_ppm = pmt::from_double(ppm);
message_port_pub(pmt::intern("ppm"), msg_ppm);
d_timer.cancel();
d_timer.async_wait(boost::bind(&clock_offset_control_impl::timed_reset, this));
d_last_fcch_time = d_current_time;
}
else
if (state == "synchronized")
{
d_timer.cancel();
d_last_fcch_time = d_current_time;
if(d_first_measurement)
{
d_ppm_estimate = ppm;

7
lib/receiver/clock_offset_control_impl.h
View File

@ -25,8 +25,6 @@
#include <grgsm/receiver/clock_offset_control.h>
#include <string>
#include <boost/asio.hpp>
#include <boost/date_time/posix_time/posix_time.hpp>
namespace gr {
namespace gsm {
@ -40,8 +38,9 @@ namespace gr {
bool d_first_measurement;
int d_counter;
std::string d_last_state;
boost::asio::io_service d_io_service;
boost::asio::deadline_timer d_timer;
float d_current_time;
float d_last_fcch_time;
bool d_first_time;
void process_measurement(pmt::pmt_t msg);
void timed_reset();

11
lib/receiver/receiver_impl.cc
View File

@ -75,7 +75,8 @@ receiver_impl::receiver_impl(int osr, const std::vector<int> &cell_allocation, c
d_failed_sch(0),
d_signal_dbm(-120),
d_tseq_nums(tseq_nums),
d_cell_allocation(cell_allocation)
d_cell_allocation(cell_allocation),
d_last_time(0.0)
{
int i;
//don't send samples to the receiver until there are at least samples for one
@ -111,6 +112,14 @@ receiver_impl::work(int noutput_items,
uint64_t start = nitems_read(0);
uint64_t stop = start + noutput_items;
float current_time = static_cast<float>(start)/(GSM_SYMBOL_RATE*d_OSR);
if((current_time - d_last_time) > 0.1)
{
pmt::pmt_t msg = pmt::make_tuple(pmt::mp("current_time"),pmt::from_double(current_time));
message_port_pub(pmt::mp("measurements"), msg);
d_last_time = current_time;
}
pmt::pmt_t key = pmt::string_to_symbol("setting_freq_offset");
get_tags_in_range(freq_offset_tags, 0, start, stop, key);
bool freq_offset_tag_in_fcch = false;

2
lib/receiver/receiver_impl.h
View File

@ -47,6 +47,8 @@ namespace gr {
gr_complex d_sch_training_seq[N_SYNC_BITS]; ///<encoded training sequence of a SCH burst
gr_complex d_norm_training_seq[TRAIN_SEQ_NUM][N_TRAIN_BITS]; ///<encoded training sequences of a normal and dummy burst
float d_last_time;
/** Counts samples consumed by the receiver
*
* It is used in beetween find_fcch_burst and reach_sch_burst calls.