/* * 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/NR_TRANSPORT/nr_transport.h" //#define NR_SSS_DEBUG int nr_generate_sss( int16_t *d_sss, int32_t *txdataF, int16_t amp, uint8_t ssb_start_symbol, nfapi_nr_config_request_t* config, NR_DL_FRAME_PARMS *frame_parms) { int i,k,l; int m0, m1; int Nid, Nid1, Nid2; //int16_t a; int16_t x0[NR_SSS_LENGTH], x1[NR_SSS_LENGTH]; const int x0_initial[7] = { 1, 0, 0, 0, 0, 0, 0 }; const int x1_initial[7] = { 1, 0, 0, 0, 0, 0, 0 }; /// Sequence generation Nid = config->sch_config.physical_cell_id.value; Nid2 = Nid % 3; Nid1 = (Nid - Nid2)/3; for ( i=0 ; i < 7 ; i++) { x0[i] = x0_initial[i]; x1[i] = x1_initial[i]; } for ( i=0 ; i < NR_SSS_LENGTH - 7 ; i++) { x0[i+7] = (x0[i + 4] + x0[i]) % 2; x1[i+7] = (x1[i + 1] + x1[i]) % 2; } m0 = 15*(Nid1/112) + (5*Nid2); m1 = Nid1 % 112; for (i = 0; i < NR_SSS_LENGTH ; i++) { d_sss[i] = (1 - 2*x0[(i + m0) % NR_SSS_LENGTH] ) * (1 - 2*x1[(i + m1) % NR_SSS_LENGTH] ) * 23170; } #ifdef NR_SSS_DEBUG write_output("d_sss.m", "d_sss", (void*)d_sss, NR_SSS_LENGTH, 1, 1); #endif /// Resource mapping // SSS occupies a predefined position (subcarriers 56-182, symbol 2) within the SSB block starting from k = frame_parms->first_carrier_offset + frame_parms->ssb_start_subcarrier + 56; //and l = ssb_start_symbol + 2; for (int m = 0; m < NR_SSS_LENGTH; m++) { ((int16_t*)txdataF)[2*(l*frame_parms->ofdm_symbol_size + k)] = (amp * d_sss[m]) >> 15; k++; if (k >= frame_parms->ofdm_symbol_size) k-=frame_parms->ofdm_symbol_size; } #ifdef NR_SSS_DEBUG // write_output("sss_0.m", "sss_0", (void*)txdataF[0][l*frame_parms->ofdm_symbol_size], frame_parms->ofdm_symbol_size, 1, 1); #endif return 0; }