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C

/*
* Copyright 2013-2019 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: nsss.h
*
* Description: Narrowband secondary synchronization signal (NSSS)
* generation and detection.
*
*
* Reference: 3GPP TS 36.211 version 13.2.0 Release 13 Sec. 10.2.7.2
*****************************************************************************/
#ifndef SRSLTE_NSSS_H
#define SRSLTE_NSSS_H
#include <stdbool.h>
#include <stdint.h>
#include <string.h>
#include "srslte/config.h"
#include "srslte/phy/common/phy_common.h"
#include "srslte/phy/dft/dft.h"
#include "srslte/phy/utils/convolution.h"
#define SRSLTE_NSSS_NSYMB 11
#define SRSLTE_NSSS_NSC 12
#define SRSLTE_NSSS_LEN (SRSLTE_NSSS_NSYMB * SRSLTE_NSSS_NSC)
#define SRSLTE_NSSS_NUM_SEQ 4
#define SRSLTE_NSSS_TOT_LEN (SRSLTE_NSSS_NUM_SEQ * SRSLTE_NSSS_LEN)
#define SRSLTE_NSSS_CORR_FILTER_LEN 1508
#define SRSLTE_NSSS_CORR_OFFSET 412
#define SRSLTE_NUM_PCI 504
#define SRSLTE_NSSS_PERIOD 2
#define SRSLTE_NSSS_NUM_SF_DETECT (SRSLTE_NSSS_PERIOD)
// b_q_m table from 3GPP TS 36.211 v13.2.0 table 10.2.7.2.1-1
static const int b_q_m[SRSLTE_NSSS_NUM_SEQ][128] = {
{1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1},
{1, -1, -1, 1, -1, 1, 1, -1, -1, 1, 1, -1, 1, -1, -1, 1, -1, 1, 1, -1, 1, -1, -1, 1, 1, -1, -1, 1, -1, 1, 1, -1,
1, -1, -1, 1, -1, 1, 1, -1, -1, 1, 1, -1, 1, -1, -1, 1, -1, 1, 1, -1, 1, -1, -1, 1, 1, -1, -1, 1, -1, 1, 1, -1,
1, -1, -1, 1, -1, 1, 1, -1, -1, 1, 1, -1, 1, -1, -1, 1, -1, 1, 1, -1, 1, -1, -1, 1, 1, -1, -1, 1, -1, 1, 1, -1,
1, -1, -1, 1, -1, 1, 1, -1, -1, 1, 1, -1, 1, -1, -1, 1, -1, 1, 1, -1, 1, -1, -1, 1, 1, -1, -1, 1, -1, 1, 1, -1},
{1, -1, -1, 1, -1, 1, 1, -1, -1, 1, 1, -1, 1, -1, -1, 1, -1, 1, 1, -1, 1, -1, -1, 1, 1, -1,
-1, 1, -1, 1, 1, -1, -1, 1, 1, -1, 1, -1, -1, 1, 1, -1, -1, 1, -1, 1, 1, -1, 1, -1, -1, 1,
-1, 1, 1, -1, -1, 1, 1, -1, 1, -1, -1, 1, 1, -1, -1, 1, -1, 1, 1, -1, -1, 1, 1, -1, 1, -1,
-1, 1, -1, 1, 1, -1, 1, -1, -1, 1, 1, -1, -1, 1, -1, 1, 1, -1, -1, 1, 1, -1, 1, -1, -1, 1,
1, -1, -1, 1, -1, 1, 1, -1, 1, -1, -1, 1, -1, 1, 1, -1, -1, 1, 1, -1, 1, -1, -1, 1},
{1, -1, -1, 1, -1, 1, 1, -1, -1, 1, 1, -1, 1, -1, -1, 1, -1, 1, 1, -1, 1, -1, -1, 1, 1, -1,
-1, 1, -1, 1, 1, -1, -1, 1, 1, -1, 1, -1, -1, 1, 1, -1, -1, 1, -1, 1, 1, -1, 1, -1, -1, 1,
-1, 1, 1, -1, -1, 1, 1, -1, 1, -1, -1, 1, -1, 1, 1, -1, 1, -1, -1, 1, 1, -1, -1, 1, -1, 1,
1, -1, 1, -1, -1, 1, -1, 1, 1, -1, -1, 1, 1, -1, 1, -1, -1, 1, 1, -1, -1, 1, -1, 1, 1, -1,
-1, 1, 1, -1, 1, -1, -1, 1, -1, 1, 1, -1, 1, -1, -1, 1, 1, -1, -1, 1, -1, 1, 1, -1}};
/* Low-level API */
typedef struct SRSLTE_API {
uint32_t input_size;
uint32_t subframe_sz;
uint32_t fft_size, max_fft_size;
srslte_conv_fft_cc_t conv_fft;
cf_t* nsss_signal_time[SRSLTE_NUM_PCI];
cf_t* tmp_input;
cf_t* conv_output;
float* conv_output_abs;
float peak_values[SRSLTE_NUM_PCI];
float corr_peak_threshold;
} srslte_nsss_synch_t;
SRSLTE_API int srslte_nsss_synch_init(srslte_nsss_synch_t* q, uint32_t input_size, uint32_t fft_size);
SRSLTE_API void srslte_nsss_synch_free(srslte_nsss_synch_t* q);
SRSLTE_API int srslte_nsss_synch_resize(srslte_nsss_synch_t* q, uint32_t fft_size);
SRSLTE_API int srslte_nsss_sync_find(
srslte_nsss_synch_t* q, cf_t* input, float* corr_peak_value, uint32_t* cell_id, uint32_t* sfn_partial);
void srslte_nsss_sync_find_pci(srslte_nsss_synch_t* q, cf_t* input, uint32_t cell_id);
SRSLTE_API int srslte_nsss_corr_init(srslte_nsss_synch_t* q);
SRSLTE_API void srslte_nsss_generate(cf_t* signal, uint32_t cell_id);
SRSLTE_API void srslte_nsss_put_subframe(srslte_nsss_synch_t* q,
cf_t* nsss,
cf_t* subframe,
const int nf,
const uint32_t nof_prb,
const uint32_t nbiot_prb_offset);
#endif // SRSLTE_NSSS_H