mirror of https://github.com/PentHertz/srsLTE.git
103 lines
3.0 KiB
C
103 lines
3.0 KiB
C
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/*
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* Copyright 2013-2020 Software Radio Systems Limited
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*
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* This file is part of srsLTE.
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*
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* srsLTE is free software: you can redistribute it and/or modify
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* it under the terms of the GNU Affero General Public License as
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* published by the Free Software Foundation, either version 3 of
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* the License, or (at your option) any later version.
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*
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* srsLTE is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU Affero General Public License for more details.
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*
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* A copy of the GNU Affero General Public License can be found in
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* the LICENSE file in the top-level directory of this distribution
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* and at http://www.gnu.org/licenses/.
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*
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*/
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/******************************************************************************
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* File: resampler.h
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*
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* Description: Linear and vector interpolation
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*
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* Reference:
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*****************************************************************************/
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#ifndef SRSLTE_RESAMPLER_H
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#define SRSLTE_RESAMPLER_H
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#include <stdbool.h>
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#include <stdint.h>
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#include "srslte/config.h"
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#include "srslte/phy/dft/dft.h"
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#ifdef __cplusplus
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extern "C" {
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#endif
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/**
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* Resampler operating modes
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*/
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typedef enum {
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SRSLTE_RESAMPLER_MODE_INTERPOLATE = 0,
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SRSLTE_RESAMPLER_MODE_DECIMATE,
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} srslte_resampler_mode_t;
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/**
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* Resampler internal buffers and subcomponents
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*/
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typedef struct {
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srslte_resampler_mode_t mode;
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uint32_t ratio;
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uint32_t window_sz;
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srslte_dft_plan_t fft;
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srslte_dft_plan_t ifft;
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uint32_t state_len;
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cf_t* in_buffer;
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cf_t* out_buffer;
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cf_t* state;
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cf_t* filter;
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} srslte_resampler_fft_t;
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/**
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* Initialise an FFT based resampler which can be configured as decimator or interpolator.
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* @param q Object pointer
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* @param mode Determines whether the operation mode is decimation or interpolation
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* @param ratio Operational ratio
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* @return SRSLTE_SUCCES if no error, otherwise an SRSLTE error code
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*/
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SRSLTE_API int srslte_resampler_fft_init(srslte_resampler_fft_t* q, srslte_resampler_mode_t mode, uint32_t ratio);
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/**
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* Get delay from the FFT based resampler.
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* @param q Object pointer
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* @return the delay in number of samples
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*/
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SRSLTE_API uint32_t srslte_resampler_fft_get_delay(srslte_resampler_fft_t* q);
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/**
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* Run FFT based resampler in the initiated mode.
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* @param q Object pointer, make sure it has been initialised
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* @param input Points at the input complex buffer
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* @param output Points at the output complex buffer
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* @param nsamples Number of samples to apply the processing
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*/
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SRSLTE_API void srslte_resampler_fft_run(srslte_resampler_fft_t* q, const cf_t* input, cf_t* output, uint32_t nsamples);
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/**
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* Free FFT based resampler buffers and subcomponents
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* @param q Object pointer
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*/
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SRSLTE_API void srslte_resampler_fft_free(srslte_resampler_fft_t* q);
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#ifdef __cplusplus
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}
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#endif
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#endif // SRSLTE_RESAMPLER_H
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