srsLTE/lib/channel/src/ch_awgn.c

53 lines
1.4 KiB
C

/*
* Copyright (c) 2013, Ismael Gomez-Miguelez <gomezi@tcd.ie>.
* This file is part of OSLD-lib (http://https://github.com/ismagom/osld-lib)
*
* OSLD-lib is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* OSLD-lib is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with OSLD-lib. If not, see <http://www.gnu.org/licenses/>.
*/
#include <complex.h>
#include <stdlib.h>
#include <strings.h>
#include "gauss.h"
#include "channel/ch_awgn.h"
void ch_awgn(const cf* x, cf* y, float variance, int buff_sz) {
_Complex float tmp;
int i;
for (i=0;i<buff_sz;i++) {
__real__ tmp = rand_gauss();
__imag__ tmp = rand_gauss();
tmp *= variance;
y[i] = tmp + x[i];
}
}
/* High-level API */
int ch_awgn_initialize(ch_awgn_hl* hl) {
return 0;
}
int ch_awgn_work(ch_awgn_hl* hl) {
ch_awgn(hl->input,hl->output,hl->ctrl_in.variance,hl->in_len);
hl->out_len = hl->in_len;
return 0;
}
int ch_awgn_stop(ch_awgn_hl* hl) {
return 0;
}