/* -*- c++ -*- */ /* * Copyright 2007,2011 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 this program; if not, write to the Free Software Foundation, Inc., * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. */ #ifndef INCLUDED_DIGITAL_OFDM_INSERT_PREAMBLE_H #define INCLUDED_DIGITAL_OFDM_INSERT_PREAMBLE_H #include <digital_api.h> #include <gr_block.h> #include <vector> class digital_ofdm_insert_preamble; typedef boost::shared_ptr<digital_ofdm_insert_preamble> digital_ofdm_insert_preamble_sptr; DIGITAL_API digital_ofdm_insert_preamble_sptr digital_make_ofdm_insert_preamble(int fft_length, const std::vector<std::vector<gr_complex> > &preamble); /*! * \brief insert "pre-modulated" preamble symbols before each payload. * \ingroup sync_blk * \ingroup ofdm_blk * * <pre> * input 1: stream of vectors of gr_complex [fft_length] * These are the modulated symbols of the payload. * * input 2: stream of char. The LSB indicates whether the corresponding * symbol on input 1 is the first symbol of the payload or not. * It's a 1 if the corresponding symbol is the first symbol, * otherwise 0. * * N.B., this implies that there must be at least 1 symbol in the payload. * * * output 1: stream of vectors of gr_complex [fft_length] * These include the preamble symbols and the payload symbols. * * output 2: stream of char. The LSB indicates whether the corresponding * symbol on input 1 is the first symbol of a packet (i.e., the * first symbol of the preamble.) It's a 1 if the corresponding * symbol is the first symbol, otherwise 0. * </pre> * * \param fft_length length of each symbol in samples. * \param preamble vector of symbols that represent the pre-modulated preamble. */ class DIGITAL_API digital_ofdm_insert_preamble : public gr_block { friend DIGITAL_API digital_ofdm_insert_preamble_sptr digital_make_ofdm_insert_preamble(int fft_length, const std::vector<std::vector<gr_complex> > &preamble); protected: digital_ofdm_insert_preamble(int fft_length, const std::vector<std::vector<gr_complex> > &preamble); private: enum state_t { ST_IDLE, ST_PREAMBLE, ST_FIRST_PAYLOAD, ST_PAYLOAD }; int d_fft_length; const std::vector<std::vector<gr_complex> > d_preamble; state_t d_state; int d_nsymbols_output; int d_pending_flag; void enter_idle(); void enter_first_payload(); void enter_payload(); public: ~digital_ofdm_insert_preamble(); void enter_preamble(); int general_work (int noutput_items, gr_vector_int &ninput_items, gr_vector_const_void_star &input_items, gr_vector_void_star &output_items); void forecast (int noutput_items, gr_vector_int &ninput_items_required); }; #endif /* INCLUDED_DIGITAL_OFDM_INSERT_PREAMBLE_H */