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Diffstat (limited to 'gr-digital/include/digital_ofdm_carrier_allocator_cvc.h')
| -rw-r--r-- | gr-digital/include/digital_ofdm_carrier_allocator_cvc.h | 116 |
1 files changed, 116 insertions, 0 deletions
diff --git a/gr-digital/include/digital_ofdm_carrier_allocator_cvc.h b/gr-digital/include/digital_ofdm_carrier_allocator_cvc.h new file mode 100644 index 0000000000..c1efcead22 --- /dev/null +++ b/gr-digital/include/digital_ofdm_carrier_allocator_cvc.h @@ -0,0 +1,116 @@ +/* -*- c++ -*- */ +/* Copyright 2012 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_CARRIER_ALLOCATOR_CVC_H +#define INCLUDED_DIGITAL_OFDM_CARRIER_ALLOCATOR_CVC_H + +#include <digital_api.h> +#include <gr_tagged_stream_block.h> + +class digital_ofdm_carrier_allocator_cvc; +typedef boost::shared_ptr<digital_ofdm_carrier_allocator_cvc> digital_ofdm_carrier_allocator_cvc_sptr; + +/* + * \param occupied_carriers A vector of vectors of indexes. Example: if + * occupied_carriers = ((1, 2, 3), (1, 2, 4)), the first + * three input symbols will be mapped to carriers 1, 2 + * and 3. After that, a new OFDM symbol is started. The next + * three input symbols will be placed onto carriers 1, 2 + * and 4 of the second OFDM symbol. The allocation then + * starts from the beginning. + * Order matters! The first input symbol is always mapped + * onto occupied_carriers[0][0]. + * \param pilot_carriers The position of the pilot symbols. Same as occupied_carriers, + * but the actual symbols are taken from pilot_symbols instead + * of the input stream. + * \param pilot_symbols The pilot symbols which are placed onto the pilot carriers. + * pilot_symbols[0][0] is placed onto the first OFDM symbol, on + * carrier index pilot_carriers[0][0] etc. + * \param len_tag_key The key of the tag identifying the length of the input packet. + */ +DIGITAL_API digital_ofdm_carrier_allocator_cvc_sptr +digital_make_ofdm_carrier_allocator_cvc ( + int fft_len, + const std::vector<std::vector<int> > &occupied_carriers, + const std::vector<std::vector<int> > &pilot_carriers, + const std::vector<std::vector<gr_complex> > &pilot_symbols, + const std::string &len_tag_key = "packet_len"); + +/*! + * \brief Create frequency domain OFDM symbols from complex values, add pilots. + * \ingroup ofdm_blk + * + * This block turns a stream of complex, scalar modulation symbols into vectors + * which are the input for an IFFT in an OFDM transmitter. It also supports the + * possibility of placing pilot symbols onto the carriers. + * + * The carriers can be allocated freely, if a carrier is not allocated, it is set + * to zero. This allows doing OFDMA-style carrier allocations. + * + * Input: A tagged stream of complex scalars. The first item must have a tag + * containing the number of complex symbols in this frame. + * Output: A tagged stream of complex vectors of length fft_len. This can directly + * be connected to an FFT block. Make sure to set this block to 'reverse' + * for the IFFT and to deactivate FFT shifting. + * + * Carrier indexes are always such that index 0 is the DC carrier (note: you should + * not allocate this carrier). The carriers below the DC carrier are either indexed + * with negative numbers, or with indexes larger than fft_len/2. Index -1 and index + * fft_len-1 both identify the carrier below the DC carrier. + * + */ +class DIGITAL_API digital_ofdm_carrier_allocator_cvc : public gr_tagged_stream_block +{ + private: + friend DIGITAL_API digital_ofdm_carrier_allocator_cvc_sptr digital_make_ofdm_carrier_allocator_cvc (int fft_len, const std::vector<std::vector<int> > &occupied_carriers, const std::vector<std::vector<int> > &pilot_carriers, const std::vector<std::vector<gr_complex> > &pilot_symbols, const std::string &len_tag_key); + + digital_ofdm_carrier_allocator_cvc(int fft_len, const std::vector<std::vector<int> > &occupied_carriers, const std::vector<std::vector<int> > &pilot_carriers, const std::vector<std::vector<gr_complex> > &pilot_symbols, const std::string &len_tag_key); + + //! FFT length + const int d_fft_len; + //! Which carriers/symbols carry data + std::vector<std::vector<int> > d_occupied_carriers; + //! Which carriers/symbols carry pilots symbols + std::vector<std::vector<int> > d_pilot_carriers; + //! Value of said pilot symbols + const std::vector<std::vector<gr_complex> > d_pilot_symbols; + int d_symbols_per_set; + + protected: + int calculate_output_stream_length(const gr_vector_int &ninput_items); + + public: + ~digital_ofdm_carrier_allocator_cvc(); + + std::string len_tag_key() { return d_length_tag_key_str; }; + + const int fft_len() { return d_fft_len; }; + std::vector<std::vector<int> > occupied_carriers() { return d_occupied_carriers; }; + + int work (int noutput_items, + gr_vector_int &ninput_items, + gr_vector_const_void_star &input_items, + gr_vector_void_star &output_items); +}; + +#endif /* INCLUDED_DIGITAL_OFDM_CARRIER_ALLOCATOR_CVC_H */ + |