/** * * \section COPYRIGHT * * Copyright 2013-2021 Software Radio Systems Limited * * By using this file, you agree to the terms and conditions set * forth in the LICENSE file which can be found at the top level of * the distribution. * */ /********************************************************************************************** * File: ch_awgn.h * * Description: Additive white gaussian noise channel object * * Reference: *********************************************************************************************/ #include "srsran/config.h" #include #ifndef SRSRAN_CH_AWGN_H #define SRSRAN_CH_AWGN_H #ifdef __cplusplus extern "C" { #endif /** * The srsRAN channel AWGN implements an efficient Box-Muller Method accelerated with SIMD. */ typedef struct { float* table_cos; float* table_log; uint32_t rand_state; float std_dev; } srsran_channel_awgn_t; /** * Initialization function of the channel AWGN object * * @param q AWGN channel object * @param seed random generator seed */ SRSRAN_API int srsran_channel_awgn_init(srsran_channel_awgn_t* q, uint32_t seed); /** * Sets the noise level N0 in decibels full scale (dBfs) * * @param q AWGN channel object * @param n0_dBfs noise level */ SRSRAN_API int srsran_channel_awgn_set_n0(srsran_channel_awgn_t* q, float n0_dBfs); /** * Runs the complex AWGN channel * * @param q AWGN channel object * @param in complex input array * @param out complex output array * @param length number of samples */ SRSRAN_API void srsran_channel_awgn_run_c(srsran_channel_awgn_t* q, const cf_t* in, cf_t* out, uint32_t length); /** * Runs the real AWGN channel * * @param q AWGN channel object * @param in real input array * @param out real output array * @param length number of samples */ SRSRAN_API void srsran_channel_awgn_run_f(srsran_channel_awgn_t* q, const float* in, float* out, uint32_t length); /** * Free AWGN channel generator data * * @param q AWGN channel object */ SRSRAN_API void srsran_channel_awgn_free(srsran_channel_awgn_t* q); SRSRAN_API void srsran_ch_awgn_c(const cf_t* input, cf_t* output, float variance, uint32_t len); SRSRAN_API void srsran_ch_awgn_f(const float* x, float* y, float variance, uint32_t len); SRSRAN_API float srsran_ch_awgn_get_variance(float ebno_db, float rate); #ifdef __cplusplus } #endif #endif // SRSRAN_CH_AWGN_H