/* * 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/LTE_TRANSPORT/dci.c * \brief Implements PDCCH physical channel TX/RX procedures (36.211) and DCI encoding/decoding (36.212/36.213). Current LTE compliance V8.6 2009-03. * \author R. Knopp * \date 2011 * \version 0.1 * \company Eurecom * \email: knopp@eurecom.fr * \note * \warning */ #include #include #include #include "PHY/defs_eNB.h" #include "PHY/phy_extern.h" #include "SCHED/sched_eNB.h" #include "SIMULATION/TOOLS/sim.h" // for taus #include "PHY/sse_intrin.h" #include "transport_proto.h" #include "transport_common_proto.h" #include "assertions.h" #include "common/utils/LOG/log.h" #include "PHY/LTE_REFSIG/lte_refsig.h" //#define DEBUG_DCI_ENCODING 1 //#define DEBUG_DCI_DECODING 1 //#define DEBUG_PHY #if (LTE_RRC_VERSION >= MAKE_VERSION(14, 0, 0)) void generate_edci_top(PHY_VARS_eNB *eNB, int frame, int subframe) { } void mpdcch_scrambling(LTE_DL_FRAME_PARMS *frame_parms, mDCI_ALLOC_t *mdci, uint16_t i, uint8_t *e, uint32_t length) { int n; uint8_t reset; uint32_t x1, x2, s=0; uint8_t Nacc=4; uint16_t j0,j,idelta; uint16_t i0 = mdci->i0; // Note: we could actually not do anything if i-i0 < Nacc, save it for later reset = 1; // x1 is set in lte_gold_generic if ((mdci->rnti == 0xFFFE) || (mdci->ce_mode == 2)) // CEModeB Note: also for mdci->rnti==SC_RNTI Nacc=frame_parms->frame_type == FDD ? 4 : 10; else Nacc=1; if (frame_parms->frame_type == FDD || Nacc == 1) idelta = 0; else idelta = Nacc-2; j0 = (i0+idelta)/Nacc; j = (i - i0)/Nacc; // rule for BL/CE UEs from Section 6.8.B2 in 36.211 x2= ((((j0+j)*Nacc)%10)<<9) + mdci->dmrs_scrambling_init; for (n=0; n>(i&0x1f))&1); } } // this table is the allocation of modulated MPDCCH format 5 symbols to REs // There are in total 36 REs/ECCE * 4 ECCE/PRB_pair = 144 REs in total/PRB_pair, total is 168 REs => 24 REs for DMRS // For format 5 there are 6 PRB pairs => 864 REs for 24 total ECCE static uint16_t mpdcch5tab[864]; void init_mpdcch5tab_normal_regular_subframe_evenNRBDL(PHY_VARS_eNB *eNB) { int l,k,kmod,re; LOG_I(PHY,"Inititalizing mpdcch5tab for normal prefix, normal prefix, no PSS/SSS/PBCH, even N_RB_DL\n"); for (l=0,re=0;l<14;l++) { for (k=0;k<72;k++){ kmod = k % 12; if (((l!=5) && (l!=6) && (l!=12) && (l!=13)) || (((l==5)||(l==6)||(l==12)||(l==13))&&(kmod!=0)&&(kmod!=5)&&(kmod!=10))) mpdcch5tab[re++]=(l*eNB->frame_parms.ofdm_symbol_size)+k; } } AssertFatal(re==864,"RE count not equal to 864\n"); } extern uint8_t *generate_dci0(uint8_t *dci, uint8_t *e, uint8_t DCI_LENGTH, uint8_t aggregation_level, uint16_t rnti); void generate_mdci_top(PHY_VARS_eNB *eNB, int frame, int subframe,int16_t amp,int32_t **txdataF) { LTE_eNB_MPDCCH *mpdcch= &eNB->mpdcch_vars[subframe&2]; mDCI_ALLOC_t *mdci; int coded_bits; LTE_DL_FRAME_PARMS *fp=&eNB->frame_parms; int i; int gain_lin_QPSK; for (i=0;inum_dci;i++) { mdci = &mpdcch->mdci_alloc[i]; AssertFatal(fp->frame_type==FDD,"TDD is not yet supported for MPDCCH\n"); AssertFatal(fp->Ncp == NORMAL,"Extended Prefix not yet supported for MPDCCH\n"); AssertFatal(mdci->L<=24,"L is %d\n",mdci->L); AssertFatal(fp->N_RB_DL==50 || fp->N_RB_DL==100,"Only N_RB_DL=50,100 for MPDCCH\n"); // Force MPDDCH format 5 AssertFatal(mdci->number_of_prb_pairs==6,"2 or 4 PRB pairs not support yet for MPDCCH\n"); AssertFatal(mdci->reps>0,"mdci->reps==0\n"); // 9 REs/EREG * 4 EREG/ECCE => 36 REs/ECCE => 72 bits/ECCE, so same as regular PDCCH channel encoding // Note: We only have to run this every Nacc subframes during repetitions, data and scrambling are constant, but we do it for now to simplify during testing generate_dci0(mdci->dci_pdu, mpdcch->e+(72*mdci->firstCCE), mdci->dci_length, mdci->L, mdci->rnti); coded_bits = 72 * mdci->L; // scrambling uint16_t absSF = (frame*10)+subframe; AssertFatal(absSF < 1024, "Absolute subframe %d = %d*10 + %d > 1023\n", absSF,frame,subframe); mpdcch_scrambling(fp, mdci, absSF, mpdcch->e+(72*mdci->firstCCE), coded_bits); // Modulation for PDCCH if (fp->nb_antenna_ports_eNB==1) gain_lin_QPSK = (int16_t)((amp*ONE_OVER_SQRT2_Q15)>>15); else gain_lin_QPSK = amp/2; uint8_t *e_ptr = mpdcch->e; // if (mdci->transmission_type==0) nprime=mdci->rnti&3; // for Localized 2+4 we use 6.8B.5 rule // map directly to one antenna port for now // Note: aside from the antenna port mapping, there is no difference between localized and distributed transmission for MPDCCH format 5 // first RE of narrowband // mpdcchtab5 below contains the mapping from each coded symbol to relative RE avoiding the DMRS int re_offset = fp->first_carrier_offset + 1 + ((fp->N_RB_DL==100)?1:0) + mdci->narrowband*12*6; if (re_offset>fp->ofdm_symbol_size) re_offset-=(fp->ofdm_symbol_size-1); int32_t *txF = &txdataF[0][re_offset]; int32_t yIQ; for (i=0; i<(coded_bits>>1); i++) { // QPSK modulation to yIQ ((int16_t*)&yIQ)[0] = (*e_ptr == 1) ? -gain_lin_QPSK : gain_lin_QPSK; e_ptr++; ((int16_t*)&yIQ)[1] = (*e_ptr == 1) ? -gain_lin_QPSK : gain_lin_QPSK; e_ptr++; txF[mpdcch5tab[i+(36*mdci->firstCCE)]] = yIQ; } } } #endif