/* * 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.h" #include "PHY/extern.h" #include "UTIL/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 void lte_adjust_synch(LTE_DL_FRAME_PARMS *frame_parms, PHY_VARS_UE *ue, unsigned char eNB_id, uint8_t subframe, unsigned char clear, short coef) { static int max_pos_fil = 0; static int count_max_pos_ok = 0; static int first_time = 1; int temp = 0, i, aa, max_val = 0, max_pos = 0; int diff; short Re,Im,ncoef; VCD_SIGNAL_DUMPER_DUMP_FUNCTION_BY_NAME(VCD_SIGNAL_DUMPER_FUNCTIONS_UE_ADJUST_SYNCH, VCD_FUNCTION_IN); ncoef = 32767 - coef; #ifdef DEBUG_PHY LOG_D(PHY,"AbsSubframe %d.%d: rx_offset (before) = %d\n",ue->proc.proc_rxtx[0].frame_rx%1024,subframe,ue->rx_offset); #endif //DEBUG_PHY // we only use channel estimates from tx antenna 0 here for (i = 0; i < frame_parms->nb_prefix_samples; i++) { temp = 0; for (aa=0; aanb_antennas_rx; aa++) { Re = ((int16_t*)ue->common_vars.common_vars_rx_data_per_thread[ue->current_thread_id[subframe]].dl_ch_estimates_time[eNB_id][aa])[(i<<2)]; Im = ((int16_t*)ue->common_vars.common_vars_rx_data_per_thread[ue->current_thread_id[subframe]].dl_ch_estimates_time[eNB_id][aa])[1+(i<<2)]; temp += (Re*Re/2) + (Im*Im/2); } if (temp > max_val) { max_pos = i; max_val = temp; } } // filter position to reduce jitter if (clear == 1) max_pos_fil = max_pos; else max_pos_fil = ((max_pos_fil * coef) + (max_pos * ncoef)) >> 15; // do not filter to have proactive timing adjustment max_pos_fil = max_pos; if(subframe == 6) { diff = max_pos_fil - (frame_parms->nb_prefix_samples>>3); #if BASIC_SIMULATOR /* a hack without which the UE does not connect (to be fixed somehow) */ diff = 0; #endif if ( abs(diff) < SYNCH_HYST ) ue->rx_offset = 0; else ue->rx_offset = diff; if(abs(diff)<5) count_max_pos_ok ++; else count_max_pos_ok = 0; if(count_max_pos_ok > 10 && first_time == 1) { first_time = 0; ue->time_sync_cell = 1; if (ue->mac_enabled==1) { LOG_I(PHY,"[UE%d] Sending synch status to higher layers\n",ue->Mod_id); //mac_resynch(); dl_phy_sync_success(ue->Mod_id,ue->proc.proc_rxtx[0].frame_rx,0,1);//ue->common_vars.eNb_id); ue->UE_mode[0] = PRACH; } else { ue->UE_mode[0] = PUSCH; } } if ( ue->rx_offset < 0 ) ue->rx_offset += FRAME_LENGTH_COMPLEX_SAMPLES; if ( ue->rx_offset >= FRAME_LENGTH_COMPLEX_SAMPLES ) ue->rx_offset -= FRAME_LENGTH_COMPLEX_SAMPLES; #ifdef DEBUG_PHY LOG_D(PHY,"AbsSubframe %d.%d: ThreadId %d diff =%i rx_offset (final) = %i : clear %d,max_pos = %d,max_pos_fil = %d (peak %d) max_val %d target_pos %d \n", ue->proc.proc_rxtx[ue->current_thread_id[subframe]].frame_rx, subframe, ue->current_thread_id[subframe], diff, ue->rx_offset, clear, max_pos, max_pos_fil, temp,max_val, (frame_parms->nb_prefix_samples>>3)); #endif //DEBUG_PHY VCD_SIGNAL_DUMPER_DUMP_FUNCTION_BY_NAME(VCD_SIGNAL_DUMPER_FUNCTIONS_UE_ADJUST_SYNCH, VCD_FUNCTION_OUT); } } int lte_est_timing_advance(LTE_DL_FRAME_PARMS *frame_parms, LTE_eNB_SRS *lte_eNB_srs, unsigned int *eNB_id, unsigned char clear, unsigned char number_of_cards, short coef) { static int max_pos_fil2 = 0; int temp, i, aa, max_pos = 0,ind; int max_val=0; short Re,Im,ncoef; #ifdef DEBUG_PHY char fname[100],vname[100]; #endif ncoef = 32768 - coef; for (ind=0; indnb_antennas_rx; aa++) { // do ifft of channel estimate switch(frame_parms->N_RB_DL) { case 6: dft128((int16_t*) <e_eNB_srs->srs_ch_estimates[aa][0], (int16_t*) lte_eNB_srs->srs_ch_estimates_time[aa], 1); break; case 25: dft512((int16_t*) <e_eNB_srs->srs_ch_estimates[aa][0], (int16_t*) lte_eNB_srs->srs_ch_estimates_time[aa], 1); break; case 50: dft1024((int16_t*) <e_eNB_srs->srs_ch_estimates[aa][0], (int16_t*) lte_eNB_srs->srs_ch_estimates_time[aa], 1); break; case 100: dft2048((int16_t*) <e_eNB_srs->srs_ch_estimates[aa][0], (int16_t*) lte_eNB_srs->srs_ch_estimates_time[aa], 1); break; } #ifdef DEBUG_PHY sprintf(fname,"srs_ch_estimates_time_%d%d.m",ind,aa); sprintf(vname,"srs_time_%d%d",ind,aa); write_output(fname,vname,lte_eNB_srs->srs_ch_estimates_time[aa],frame_parms->ofdm_symbol_size*2,2,1); #endif } // we only use channel estimates from tx antenna 0 here // remember we fixed the SRS to use only every second subcarriers for (i = 0; i < frame_parms->ofdm_symbol_size/2; i++) { temp = 0; for (aa=0; aanb_antennas_rx; aa++) { Re = ((int16_t*)lte_eNB_srs->srs_ch_estimates_time[aa])[(i<<1)]; Im = ((int16_t*)lte_eNB_srs->srs_ch_estimates_time[aa])[1+(i<<1)]; temp += (Re*Re/2) + (Im*Im/2); } if (temp > max_val) { max_pos = i; max_val = temp; *eNB_id = ind; } } } // filter position to reduce jitter if (clear == 1) max_pos_fil2 = max_pos; else max_pos_fil2 = ((max_pos_fil2 * coef) + (max_pos * ncoef)) >> 15; return(max_pos_fil2); } int lte_est_timing_advance_pusch(PHY_VARS_eNB* eNB,uint8_t UE_id) { int temp, i, aa, max_pos=0, max_val=0; short Re,Im; LTE_DL_FRAME_PARMS *frame_parms = &eNB->frame_parms; LTE_eNB_PUSCH *eNB_pusch_vars = eNB->pusch_vars[UE_id]; int32_t **ul_ch_estimates_time= eNB_pusch_vars->drs_ch_estimates_time; uint8_t cyclic_shift = 0; int sync_pos = (frame_parms->ofdm_symbol_size-cyclic_shift*frame_parms->ofdm_symbol_size/12)%(frame_parms->ofdm_symbol_size); AssertFatal(frame_parms->ofdm_symbol_size > 127,"frame_parms->ofdm_symbol_size %d<128\n",frame_parms->ofdm_symbol_size); AssertFatal(frame_parms->nb_antennas_rx >0 && frame_parms->nb_antennas_rx<3,"frame_parms->nb_antennas_rx %d not in [0,1]\n", frame_parms->nb_antennas_rx); for (i = 0; i < frame_parms->ofdm_symbol_size; i++) { temp = 0; for (aa=0; aanb_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; //#ifdef DEBUG_PHY LOG_D(PHY,"frame %d: max_pos = %d, sync_pos=%d\n",eNB->proc.frame_rx,max_pos,sync_pos); //#endif //DEBUG_PHY return max_pos - sync_pos; }