74 lines
2.1 KiB
C
74 lines
2.1 KiB
C
/**
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*
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* \section COPYRIGHT
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*
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* Copyright 2013-2015 Software Radio Systems Limited
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*
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* \section LICENSE
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*
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* This file is part of the srsLTE library.
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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: cfo.h
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*
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* Description: Carrier frequency offset correction using complex exponentials.
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*
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* Reference:
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*****************************************************************************/
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#ifndef CFO_
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#define CFO_
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#include <complex.h>
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#include "srslte/config.h"
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#include "srslte/phy/utils/cexptab.h"
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/** If the frequency is changed more than the tolerance, a new table is generated */
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#define SRSLTE_CFO_TOLERANCE 0.00001
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#define SRSLTE_CFO_CEXPTAB_SIZE 4096
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typedef struct SRSLTE_API {
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float last_freq;
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float tol;
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int nsamples;
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int max_samples;
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srslte_cexptab_t tab;
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cf_t *cur_cexp;
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}srslte_cfo_t;
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SRSLTE_API int srslte_cfo_init(srslte_cfo_t *h,
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uint32_t nsamples);
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SRSLTE_API void srslte_cfo_free(srslte_cfo_t *h);
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SRSLTE_API int srslte_cfo_resize(srslte_cfo_t *h,
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uint32_t samples);
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SRSLTE_API void srslte_cfo_set_tol(srslte_cfo_t *h,
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float tol);
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SRSLTE_API void srslte_cfo_correct(srslte_cfo_t *h,
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cf_t *input,
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cf_t *output,
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float freq);
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#endif // CFO_
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