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Diffstat (limited to 'gr-digital/lib/ofdm_chanest_vcvc_impl.h')
| -rw-r--r-- | gr-digital/lib/ofdm_chanest_vcvc_impl.h | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/gr-digital/lib/ofdm_chanest_vcvc_impl.h b/gr-digital/lib/ofdm_chanest_vcvc_impl.h new file mode 100644 index 0000000000..def8734e64 --- /dev/null +++ b/gr-digital/lib/ofdm_chanest_vcvc_impl.h @@ -0,0 +1,78 @@ +/* -*- c++ -*- */ +/* + * Copyright 2013 Free Software Foundation, Inc. + * + * This file is part of GNU Radio + * + * GNU Radio is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 3, or (at your option) + * any later version. + * + * GNU Radio 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 General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with GNU Radio; see the file COPYING. If not, write to + * the Free Software Foundation, Inc., 51 Franklin Street, + * Boston, MA 02110-1301, USA. + */ + +#ifndef INCLUDED_DIGITAL_OFDM_CHANEST_VCVC_IMPL_H +#define INCLUDED_DIGITAL_OFDM_CHANEST_VCVC_IMPL_H + +#include <digital/ofdm_chanest_vcvc.h> + +namespace gr { + namespace digital { + + class ofdm_chanest_vcvc_impl : public ofdm_chanest_vcvc + { + private: + int d_fft_len; //! FFT length + int d_n_data_syms; //! Number of data symbols following the sync symbol(s) + int d_n_sync_syms; //! Number of sync symbols (1 or 2) + //! 0 if no noise reduction is done for the initial channel state estimation. Otherwise, the maximum length of the channel delay in samples. + int d_eq_noise_red_len; + //! Is sync_symbol1 if d_n_sync_syms == 1, otherwise sync_symbol2. Used as a reference symbol to estimate the channel. + std::vector<gr_complex> d_ref_sym; + //! If d_n_sync_syms == 2 this is used as a differential correlation vector (called 'v' in [1]). + std::vector<gr_complex> d_corr_v; + //! If d_n_sync_syms == 1 we use this instead of d_corr_v to estimate the coarse freq. offset + std::vector<float> d_known_symbol_diffs; + //! If d_n_sync_syms == 1 we use this instead of d_corr_v to estimate the coarse freq. offset (temp. variable) + std::vector<float> d_new_symbol_diffs; + //! The index of the first carrier with data (index 0 is not DC here, but the lowest frequency) + int d_first_active_carrier; + //! The index of the last carrier with data + int d_last_active_carrier; + //! If true, the channel estimation must be interpolated + bool d_interpolate; + //! Maximum carrier offset (negative value!) + int d_max_neg_carr_offset; + //! Maximum carrier offset (positive value!) + int d_max_pos_carr_offset; + + //! Calculate the coarse frequency offset in number of carriers + int get_carr_offset(const gr_complex *sync_sym1, const gr_complex *sync_sym2); + //! Estimate the channel (phase and amplitude offset per carrier) + void get_chan_taps(const gr_complex *sync_sym1, const gr_complex *sync_sym2, int carr_offset, std::vector<gr_complex> &taps); + + public: + ofdm_chanest_vcvc_impl(const std::vector<gr_complex> &sync_symbol1, const std::vector<gr_complex> &sync_symbol2, int n_data_symbols, int eq_noise_red_len, int max_carr_offset, bool force_one_sync_symbol); + ~ofdm_chanest_vcvc_impl(); + + void forecast (int noutput_items, gr_vector_int &ninput_items_required); + int general_work(int noutput_items, + gr_vector_int &ninput_items, + gr_vector_const_void_star &input_items, + gr_vector_void_star &output_items); + }; + + } // namespace digital +} // namespace gr + +#endif /* INCLUDED_DIGITAL_OFDM_CHANEST_VCVC_IMPL_H */ + |