/* * 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 */ /*! \file PHY/NR_ESTIMATION/nr_adjust_sync_gNB.c * \brief TA estimation for TA updates * \author Ahmed Hussein * \date 2019 * \version 0.1 * \company Fraunhofer IIS * \email: ahmed.hussein@iis.fraunhofer.de * \note * \warning */ #include "PHY/types.h" #include "PHY/defs_gNB.h" #include "PHY/phy_extern.h" #include "nr_ul_estimation.h" int nr_est_timing_advance_pusch(PHY_VARS_gNB* gNB, int UE_id) { int temp, i, aa, max_pos = 0, max_val = 0; short Re, Im; uint8_t cyclic_shift = 0; NR_DL_FRAME_PARMS *frame_parms = &gNB->frame_parms; NR_gNB_PUSCH *gNB_pusch_vars = gNB->pusch_vars[UE_id]; int32_t **ul_ch_estimates_time = gNB_pusch_vars->ul_ch_estimates_time; int sync_pos = (frame_parms->ofdm_symbol_size - cyclic_shift*frame_parms->ofdm_symbol_size/12) % (frame_parms->ofdm_symbol_size); for (i = 0; i < frame_parms->ofdm_symbol_size; i++) { temp = 0; for (aa = 0; aa < frame_parms->nb_antennas_rx; aa++) { Re = ((int16_t*)ul_ch_estimates_time[aa])[(i<<1)]; Im = ((int16_t*)ul_ch_estimates_time[aa])[1+(i<<1)]; temp += (Re*Re/2) + (Im*Im/2); } if (temp > max_val) { max_pos = i; max_val = temp; } } if (max_pos > frame_parms->ofdm_symbol_size/2) max_pos = max_pos - frame_parms->ofdm_symbol_size; return max_pos - sync_pos; }