99 lines
3.3 KiB
C
99 lines
3.3 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 "PHY/types.h"
|
|
#include "PHY/defs_nr_UE.h"
|
|
#include "PHY/NR_UE_ESTIMATION/nr_estimation.h"
|
|
#include "PHY/impl_defs_top.h"
|
|
|
|
#include "executables/softmodem-common.h"
|
|
#include "common/utils/LOG/vcd_signal_dumper.h"
|
|
|
|
//#define DEBUG_PHY
|
|
|
|
// Adjust location synchronization point to account for drift
|
|
// The adjustment is performed once per frame based on the
|
|
// last channel estimate of the receiver
|
|
|
|
int nr_adjust_synch_ue(NR_DL_FRAME_PARMS *frame_parms,
|
|
PHY_VARS_NR_UE *ue,
|
|
module_id_t gNB_id,
|
|
const int estimateSz,
|
|
struct complex16 dl_ch_estimates_time[][estimateSz],
|
|
uint8_t frame,
|
|
uint8_t slot,
|
|
short coef)
|
|
{
|
|
int max_val = 0, max_pos = 0;
|
|
uint8_t sync_offset = 0;
|
|
|
|
VCD_SIGNAL_DUMPER_DUMP_FUNCTION_BY_NAME(VCD_SIGNAL_DUMPER_FUNCTIONS_UE_ADJUST_SYNCH, VCD_FUNCTION_IN);
|
|
|
|
short ncoef = 32767 - coef;
|
|
|
|
// search for maximum position within the cyclic prefix
|
|
for (int i = -frame_parms->nb_prefix_samples/2; i < frame_parms->nb_prefix_samples/2; i++) {
|
|
int temp = 0;
|
|
|
|
int j = (i < 0) ? (i + frame_parms->ofdm_symbol_size) : i;
|
|
for (int aa = 0; aa < frame_parms->nb_antennas_rx; aa++) {
|
|
int Re = dl_ch_estimates_time[aa][j].r;
|
|
int Im = dl_ch_estimates_time[aa][j].i;
|
|
temp += (Re*Re/2) + (Im*Im/2);
|
|
}
|
|
|
|
if (temp > max_val) {
|
|
max_pos = i;
|
|
max_val = temp;
|
|
}
|
|
}
|
|
|
|
// filter position to reduce jitter
|
|
ue->max_pos_avg = ((ue->max_pos_avg * coef) >> 15) + (max_pos * ncoef);
|
|
|
|
int diff = ue->max_pos_avg >> 15;
|
|
|
|
if (frame_parms->freq_range == FR2)
|
|
sync_offset = 2;
|
|
else
|
|
sync_offset = 0;
|
|
|
|
int sampleShift = 0;
|
|
if (abs(diff) > (NR_SYNCH_HYST + sync_offset))
|
|
sampleShift = diff;
|
|
|
|
const int sample_shift = -(sampleShift / 2);
|
|
// reset IIR filter for next offset calculation
|
|
ue->max_pos_avg += sample_shift * 32768;
|
|
|
|
LOG_D(PHY,
|
|
"Slot %d: diff = %i, rx_offset (final) = %i : max_pos = %d, max_pos filtered = %ld, max_power = %d\n",
|
|
slot,
|
|
diff,
|
|
sampleShift,
|
|
max_pos,
|
|
ue->max_pos_avg,
|
|
max_val);
|
|
|
|
VCD_SIGNAL_DUMPER_DUMP_FUNCTION_BY_NAME(VCD_SIGNAL_DUMPER_FUNCTIONS_UE_ADJUST_SYNCH, VCD_FUNCTION_OUT);
|
|
return sample_shift;
|
|
}
|