/** * Copyright 2013-2021 Software Radio Systems Limited * * This file is part of srsLTE. * * srsLTE is free software: you can redistribute it and/or modify * it under the terms of the GNU Affero General Public License as * published by the Free Software Foundation, either version 3 of * the License, or (at your option) any later version. * * srsLTE is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU Affero General Public License for more details. * * A copy of the GNU Affero General Public License can be found in * the LICENSE file in the top-level directory of this distribution * and at http://www.gnu.org/licenses/. * */ /****************************************************************************** * File: prach.h * * Description: Physical random access channel. * * Reference: 3GPP TS 36.211 version 10.0.0 Release 10 Sec. 5.7 *****************************************************************************/ #ifndef SRSLTE_PRACH_H #define SRSLTE_PRACH_H #include "srslte/config.h" #include "srslte/phy/common/phy_common.h" #include "srslte/phy/dft/dft.h" #include #include #include #include #define SRSLTE_PRACH_MAX_LEN (2 * 24576 + 21024) // Maximum Tcp + Tseq // Long PRACH ZC sequence sequence length #define SRSLTE_PRACH_N_ZC_LONG 839 // Short PRACH ZC sequence sequence length #define SRSLTE_PRACH_N_ZC_SHORT 139 /** Generation and detection of RACH signals for uplink. * Currently only supports preamble formats 0-3. * Does not currently support high speed flag. * Based on 3GPP TS 36.211 version 10.7.0 Release 10. */ typedef struct { int idx; float factor; cf_t phase_array[2 * SRSLTE_PRACH_N_ZC_LONG]; } srslte_prach_cancellation_t; typedef struct SRSLTE_API { // Parameters from higher layers (extracted from SIB2) bool is_nr; uint32_t config_idx; uint32_t f; // preamble format uint32_t rsi; // rootSequenceIndex bool hs; // highSpeedFlag uint32_t zczc; // zeroCorrelationZoneConfig uint32_t N_ifft_ul; // IFFT size for uplink uint32_t N_ifft_prach; // IFFT size for PRACH generation uint32_t max_N_ifft_ul; // Working parameters uint32_t N_zc; // PRACH sequence length uint32_t N_cs; // Cyclic shift size uint32_t N_seq; // Preamble length float T_seq; // Preamble length in seconds float T_tot; // Total sequence length in seconds uint32_t N_cp; // Cyclic prefix length // Generated tables cf_t seqs[64][SRSLTE_PRACH_N_ZC_LONG]; // Our set of 64 preamble sequences cf_t dft_seqs[64][SRSLTE_PRACH_N_ZC_LONG]; // DFT-precoded seqs uint64_t dft_gen_bitmap; // Bitmap where each bit Indicates if the dft has been generated for sequence i. uint32_t root_seqs_idx[64]; // Indices of root seqs in seqs table uint32_t N_roots; // Number of root sequences used in this configuration cf_t* td_signals[64]; // Containers cf_t* ifft_in; cf_t* ifft_out; cf_t* prach_bins; cf_t* corr_spec; float* corr; // PRACH IFFT srslte_dft_plan_t fft; srslte_dft_plan_t ifft; // ZC-sequence FFT and IFFT srslte_dft_plan_t zc_fft; srslte_dft_plan_t zc_ifft; cf_t* signal_fft; float detect_factor; uint32_t deadzone; float peak_values[65]; uint32_t peak_offsets[65]; uint32_t num_ra_preambles; bool successive_cancellation; bool freq_domain_offset_calc; srslte_tdd_config_t tdd_config; uint32_t current_prach_idx; cf_t* cross; cf_t* corr_freq; srslte_prach_cancellation_t prach_cancel; cf_t sub[839 * 2]; float phase[839]; } srslte_prach_t; typedef struct SRSLTE_API { int nof_sf; uint32_t sf[5]; } srslte_prach_sf_config_t; typedef enum SRSLTE_API { SRSLTE_PRACH_SFN_EVEN = 0, SRSLTE_PRACH_SFN_ANY, } srslte_prach_sfn_t; typedef struct { bool is_nr; // Set to true if NR uint32_t config_idx; uint32_t root_seq_idx; uint32_t zero_corr_zone; uint32_t freq_offset; uint32_t num_ra_preambles; bool hs_flag; srslte_tdd_config_t tdd_config; bool enable_successive_cancellation; bool enable_freq_domain_offset_calc; } srslte_prach_cfg_t; typedef struct SRSLTE_API { uint32_t f; uint32_t t0; uint32_t t1; uint32_t t2; } srslte_prach_tdd_loc_t; typedef struct SRSLTE_API { uint32_t nof_elems; srslte_prach_tdd_loc_t elems[6]; } srslte_prach_tdd_loc_table_t; SRSLTE_API uint32_t srslte_prach_get_preamble_format(uint32_t config_idx); SRSLTE_API srslte_prach_sfn_t srslte_prach_get_sfn(uint32_t config_idx); SRSLTE_API bool srslte_prach_tti_opportunity(srslte_prach_t* p, uint32_t current_tti, int allowed_subframe); SRSLTE_API bool srslte_prach_tti_opportunity_config_fdd(uint32_t config_idx, uint32_t current_tti, int allowed_subframe); SRSLTE_API bool srslte_prach_tti_opportunity_config_tdd(uint32_t config_idx, uint32_t tdd_ul_dl_config, uint32_t current_tti, uint32_t* prach_idx); SRSLTE_API uint32_t srslte_prach_f_ra_tdd(uint32_t config_idx, uint32_t tdd_ul_dl_config, uint32_t current_tti, uint32_t prach_idx, uint32_t prach_offset, uint32_t n_rb_ul); SRSLTE_API uint32_t srslte_prach_f_id_tdd(uint32_t config_idx, uint32_t tdd_ul_dl_config, uint32_t prach_idx); SRSLTE_API uint32_t srslte_prach_nof_f_idx_tdd(uint32_t config_idx, uint32_t tdd_ul_dl_config); SRSLTE_API void srslte_prach_sf_config(uint32_t config_idx, srslte_prach_sf_config_t* sf_config); SRSLTE_API int srslte_prach_init(srslte_prach_t* p, uint32_t max_N_ifft_ul); SRSLTE_API int srslte_prach_set_cfg(srslte_prach_t* p, srslte_prach_cfg_t* cfg, uint32_t nof_prb); SRSLTE_API int srslte_prach_gen(srslte_prach_t* p, uint32_t seq_index, uint32_t freq_offset, cf_t* signal); SRSLTE_API int srslte_prach_detect(srslte_prach_t* p, uint32_t freq_offset, cf_t* signal, uint32_t sig_len, uint32_t* indices, uint32_t* ind_len); SRSLTE_API int srslte_prach_detect_offset(srslte_prach_t* p, uint32_t freq_offset, cf_t* signal, uint32_t sig_len, uint32_t* indices, float* t_offsets, float* peak_to_avg, uint32_t* ind_len); SRSLTE_API void srslte_prach_set_detect_factor(srslte_prach_t* p, float factor); SRSLTE_API int srslte_prach_free(srslte_prach_t* p); SRSLTE_API int srslte_prach_print_seqs(srslte_prach_t* p); SRSLTE_API int srslte_prach_process(srslte_prach_t* p, cf_t* signal, uint32_t* indices, float* t_offsets, float* peak_to_avg, uint32_t* n_indices, int cancellation_idx, uint32_t begin, uint32_t sig_len); #endif // SRSLTE_PRACH_H