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/**
* Copyright 2013-2021 Software Radio Systems Limited
*
* This file is part of srsRAN.
*
* srsRAN 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.
*
* srsRAN 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/.
*
*/
#ifndef SRSRAN_DMRS_PBCH_H
#define SRSRAN_DMRS_PBCH_H
#include "srsran/phy/common/phy_common_nr.h"
/**
* @brief Describes the DeModulation Reference Signals (DMRS) for NR PBCH configuration
*/
typedef struct SRSRAN_API {
uint32_t N_id; ///< Physical cell identifier
uint32_t n_hf; ///< Number of half radio frame, 0 or 1
uint32_t ssb_idx; ///< SSB candidate index, up to 3 LSB are significant
uint32_t L_max; ///< Number of SSB opportunities in half radio frame
float beta; ///< Power allocation specified in TS 38.213
srsran_subcarrier_spacing_t scs; ///< SSB configured subcarrier spacing
} srsran_dmrs_pbch_cfg_t;
/**
* @brief Describes an NR PBCH DMRS based measurement
*/
typedef struct SRSRAN_API {
float corr; ///< Normalised correlation
float epre; ///< Linear energy per resource element
float rsrp; ///< Linear RSRP
float cfo_hz; ///< CFO in Hz
float avg_delay_us; ///< Average delay in us
} srsran_dmrs_pbch_meas_t;
/**
* @brief Put NR PBCH DMRS in the SSB resource grid
* @param cfg PBCH DMRS configuration
* @param[out] ssb_grid SSB resource grid
* @return SRSRAN_SUCCESS if the inputs and configuration are valid, SRSRAN_ERROR code otherwise
*/
SRSRAN_API int srsran_dmrs_pbch_put(const srsran_dmrs_pbch_cfg_t* cfg, cf_t ssb_grid[SRSRAN_SSB_NOF_RE]);
/**
* @brief Measures NR PBCH DMRS
* @param cfg PBCH DMRS configuration
* @param ssb_grid SSB resource grid
* @param[out] meas Measurement
* @return SRSRAN_SUCCESS if the inputs and configuration are valid, SRSRAN_ERROR code otherwise
*/
SRSRAN_API int srsran_dmrs_pbch_measure(const srsran_dmrs_pbch_cfg_t* cfg,
const cf_t ssb_grid[SRSRAN_SSB_NOF_RE],
srsran_dmrs_pbch_meas_t* meas);
/**
* @brief Estimates NR PBCH DMRS
* @param cfg PBCH DMRS configuration
* @param ssb_grid Demodulated SSB resource grid
* @param[out] ce Estimated channel
* @return SRSRAN_SUCCESS if the inputs and configuration are valid, SRSRAN_ERROR code otherwise
*/
SRSRAN_API int srsran_dmrs_pbch_estimate(const srsran_dmrs_pbch_cfg_t* cfg,
const cf_t ssb_grid[SRSRAN_SSB_NOF_RE],
cf_t ce[SRSRAN_SSB_NOF_RE]);
#endif // SRSRAN_DMRS_PBCH_H