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openairinterface5g/openair1/SIMULATION/TOOLS/phase_noise.c
T

64 lines
2.3 KiB
C

/*
* Licensed to the OpenAirInterface (OAI) Software Alliance under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The OpenAirInterface Software Alliance licenses this file to You under
* the OAI Public License, Version 1.1 (the "License"); you may not use this file
* except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.openairinterface.org/?page_id=698
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*-------------------------------------------------------------------------------
* For more information about the OpenAirInterface (OAI) Software Alliance:
* contact@openairinterface.org
*/
#include <math.h>
#include "sim.h"
/* linear phase noise model */
void phase_noise(double ts, int16_t *InRe, int16_t *InIm)
{
static uint64_t i=0;
double fd = 300;//0.01*30000
double phase = (double)(i * fd * ts);
c16_t rot = get_sin_cos(phase);
c16_t val = {.r = *InRe, .i = *InIm};
val = c16mulShift(val, rot, 14);
*InRe = val.r;
*InIm = val.i;
i++;
}
void add_noise(c16_t **rxdata,
const double **r_re,
const double **r_im,
const double sigma,
const int length,
const int slot_offset,
const double ts,
const int delay,
const uint16_t pdu_bit_map,
const uint16_t ptrs_bit_map,
const uint8_t nb_antennas_rx)
{
for (int i = 0; i < length; i++) {
for (int ap = 0; ap < nb_antennas_rx; ap++) {
c16_t *rxd = &rxdata[ap][slot_offset + i + delay];
rxd->r = r_re[ap][i] + sqrt(sigma / 2) * gaussZiggurat(0.0, 1.0); // convert to fixed point
rxd->i = r_im[ap][i] + sqrt(sigma / 2) * gaussZiggurat(0.0, 1.0);
/* Add phase noise if enabled */
if (pdu_bit_map & ptrs_bit_map) {
phase_noise(ts, &rxdata[ap][slot_offset + i + delay].r, &rxdata[ap][slot_offset + i + delay].i);
}
}
}
}