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Corrections in fn_time

This commit is contained in:
Piotr Krysik 2017-11-03 09:56:49 +01:00
parent 8926c1f621
commit 6e41d06bbf
4 changed files with 54 additions and 52 deletions
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12
include/grgsm/misc_utils/fn_time.h
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@ -1,6 +1,7 @@
/* -*- c++ -*- */
/* @file
* @author Piotr Krysik <ptrkrysik@gmail.com>
* @author Vadim Yanitskiy <axilirator@gmail.com>
* @section LICENSE
*
* Gr-gsm is free software; you can redistribute it and/or modify
@ -24,8 +25,9 @@
#ifndef INCLUDED_GRGSM_FN_TIME_H
#define INCLUDED_GRGSM_FN_TIME_H
#include <grgsm/api.h>
#include <stdint.h>
#include <grgsm/misc_utils/time_spec.h>
#include <utility>
namespace gr {
namespace gsm {
@ -41,10 +43,12 @@ namespace gr {
* frame numbers
* @return difference between fn_ref and fn
*/
time_spec_t fn_time_delta2(uint32_t fn_ref, time_spec_t time_ref, uint32_t fn_x,
time_spec_t time_hint, uint32_t ts_num, uint32_t ts_ref);
typedef std::pair<unsigned long long, double> time_format;
GRGSM_API time_format fn_time_delta_cpp(uint32_t fn_ref, time_format time_ref, uint32_t fn_x,
time_format time_hint, uint32_t ts_num, uint32_t ts_ref);
} // namespace grgsm
} // namespace gsm
} // namespace gr
#endif /* INCLUDED_GRGSM_FN_TIME_H */

67
lib/misc_utils/fn_time.cc
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@ -22,35 +22,38 @@
*/
#include <grgsm/misc_utils/fn_time.h>
#include <grgsm/misc_utils/time_spec.h>
#include <math.h>
#define GSM_HYPER_FRAME 26 * 51 * 2048
#define GSM_SYM_RATE 13.0e6 / 48.0
#define GSM_HYPER_FRAME (26 * 51 * 2048)
#define GSM_SYM_RATE (13.0e6 / 48.0)
#define GSM_TS_PERIOD 156.25 / GSM_SYM_RATE
#define GSM_FN_PERIOD 8 * GSM_TS_PERIOD
#define GSM_TS_PERIOD (156.25 / GSM_SYM_RATE)
#define GSM_FN_PERIOD (8 * GSM_TS_PERIOD)
namespace gr {
namespace gsm {
/**
* Computes difference between two frame numbers modulo
* GSM_HYPER_FRAME / 2. The result is correct if difference
* between the frame numbers is not bigger than GSM_HYPER_FRAME / 2.
* @param fn1 first frame number
* @param fn2 second frame number
* @return computed difference
*/
static uint32_t fnmod_delta(uint32_t fn1, uint32_t fn2)
/**
* Computes difference between two frame numbers modulo
* GSM_HYPER_FRAME / 2. The result is correct if difference
* between the frame numbers is not bigger than GSM_HYPER_FRAME / 2.
* @param fn1 first frame number
* @param fn2 second frame number
* @return computed difference
*/
static int fnmod_delta(uint32_t fn1, uint32_t fn2)
{
uint32_t delta, h2;
int delta, h2;
delta = (fn1 % GSM_HYPER_FRAME) - (fn2 % GSM_HYPER_FRAME);
h2 = GSM_HYPER_FRAME / 2;
if (delta >= h2)
delta -= GSM_HYPER_FRAME;
else
delta += GSM_HYPER_FRAME;
if (delta >= h2) {
delta -= GSM_HYPER_FRAME;
} else if(delta < -h2) {
delta += GSM_HYPER_FRAME;
}
return delta;
}
@ -59,7 +62,6 @@ namespace gr {
time_spec_t time_diff_hint)
{
int frames_diff, fn_delta;
frames_diff = int(round(time_diff_hint.get_real_secs() / GSM_FN_PERIOD));
fn_delta = fnmod_delta(fn, fn_ref + frames_diff) + frames_diff;
@ -77,27 +79,16 @@ namespace gr {
* frame numbers
* @return difference between fn_ref and fn
*/
time_spec_t fn_time_delta2(uint32_t fn_ref, time_spec_t time_ref, uint32_t fn_x,
time_spec_t time_hint, uint32_t ts_num, uint32_t ts_ref)
time_format fn_time_delta_cpp(uint32_t fn_ref, time_format time_ref, uint32_t fn_x,
time_format time_hint, uint32_t ts_num, uint32_t ts_ref)
{
time_spec_t time_diff_hint = time_hint - time_ref;
uint32_t fn_delta = fn_time_diff_delta(fn_x,fn_ref, time_diff_hint);
time_spec_t time_x_precise = fn_delta * GSM_FN_PERIOD
+ time_ref + (ts_num - ts_ref) * GSM_TS_PERIOD;
return time_x_precise;
time_spec_t time_diff_hint = time_spec_t(time_hint.first, time_hint.second) - time_spec_t(time_ref.first, time_ref.second);
int fn_delta = fn_time_diff_delta(fn_x, fn_ref, time_diff_hint);
time_spec_t time_x_precise = fn_delta * GSM_FN_PERIOD + time_spec_t(time_ref.first, time_ref.second) + (static_cast<int>(ts_num) - static_cast<int>(ts_ref)) * GSM_TS_PERIOD;
return time_format(time_x_precise.get_full_secs(), time_x_precise.get_frac_secs());
}
/*
def fn_time_delta(fn_ref, time_ref, fn_x, time_hint=None, ts_num=0, ts_ref=0):
if time_hint is None:
time_hint = time_ref
time_diff_hint = time_hint-time_ref
fn_delta = fn_time_diff_delta(fn_x,fn_ref, time_diff_hint)
time_x_precise = fn_delta*__frame_period+time_ref+(ts_num-ts_ref)*__ts_period
return fn_delta, time_x_precise
*/
} /* namespace gsm */
} /* namespace gr */

20
python/misc_utils/fn_time.py
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@ -22,6 +22,7 @@
#
from math import floor, ceil
from random import uniform
from grgsm import fn_time_delta_cpp
__hyper_frame = 26*51*2048
__symb_rate = 13.0e6/48.0
@ -37,7 +38,7 @@ __frame_period = 8*__ts_period
def fnmod_delta(fn1, fn2):
h2 = __hyper_frame/2
delta = (fn1%__hyper_frame)-(fn2%__hyper_frame)
if delta >= h2:
delta = delta - __hyper_frame
elif delta < -h2:
@ -49,7 +50,7 @@ def fn_time_diff_delta(fn_x, fn_ref, time_diff_hint=0):
frames_diff = int(round(time_diff_hint/__frame_period))
fn_ref_hint = (fn_ref + frames_diff)
fn_delta = fnmod_delta(fn_x,fn_ref_hint)+frames_diff
return fn_delta
#fn_time_delta computes difference between reference frame number and a second frame number. It also computes timestamp of the second frame number. The full list of parameters is following:
@ -73,16 +74,19 @@ def fn_time_delta(fn_ref, time_ref, fn_x, time_hint=None, ts_num=0, ts_ref=0):
if __name__ == "__main__":
fn1 = 10000
ts_ref = 4
time1 = 10
for fn2 in xrange(__hyper_frame/2+fn1-10,__hyper_frame/2*10+fn1+10,10):
time1 = 10.5
for fn2 in xrange(__hyper_frame/2+fn1-10,__hyper_frame/2*10+fn1+100,10):
ts_x = int(uniform(0,8))
time2 = time1 + (fn2-fn1)*__frame_period + (ts_ref-ts_x)*__ts_period
time2 = time1 + (fn2-fn1)*__frame_period + (ts_x-ts_ref)*__ts_period
error = uniform(-6200,6200)
time2_err = time2+error
fn_delta, time2_precise = fn_time_delta(fn1, time1, fn2, time2_err, ts_x, ts_ref)
time2_precise_cpp = fn_time_delta_cpp(fn1, (int(time1),time1-int(time1)), fn2, (int(time2_err),time2_err-int(time2_err)), ts_x, ts_ref)
if fn_delta != fn2-fn1:
print "bad fn:", fn2, error#, 'fn_delta:'+str(fn_delta), time2, error, frames_diff_h4, (time2-time1)/(__hyper_frame*__frame_period), time_diff_hint_h4_prev, time_diff_hint
time_diff_hint = time2 - time2_precise
if time_diff_hint > 0.0001:
print "bad time diff"
# time_diff_hint = time2 - time2_precise
time_diff_hint = time2_precise_cpp[0]+time2_precise_cpp[1] - time2_precise
if abs(time_diff_hint) > 0.0001:
print "time2_precise_cpp",time2_precise_cpp," time2_precise",time2_precise," time_ref",time1," time_hint",time2_err
print ""

7
swig/grgsm_swig.i
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@ -23,6 +23,9 @@
#define GRGSM_API
%include <std_pair.i>
%template(pairud) std::pair<unsigned long long,double>;
%include "gnuradio.i" // the common stuff
//load generated python docstrings
@ -65,7 +68,7 @@
#include "grgsm/misc_utils/msg_to_tag.h"
#include "grgsm/misc_utils/controlled_fractional_resampler_cc.h"
#include "grgsm/trx_interface/trx.h"
#include "grgsm/misc_utils/time_spec.h"
//#include "grgsm/misc_utils/time_spec.h"
#include "grgsm/misc_utils/fn_time.h"
%}
@ -149,4 +152,4 @@ GR_SWIG_BLOCK_MAGIC2(gsm, message_sink);
%include "grgsm/trx_interface/trx.h"
GR_SWIG_BLOCK_MAGIC2(grgsm, trx);
//%include "grgsm/misc_utils/time_spec.h"
//%include "grgsm/misc_utils/fn_time.h"
%include "grgsm/misc_utils/fn_time.h"