diff options
Diffstat (limited to 'gr-digital/include/digital/ofdm_cyclic_prefixer.h')
| -rw-r--r-- | gr-digital/include/digital/ofdm_cyclic_prefixer.h | 50 |
1 files changed, 32 insertions, 18 deletions
diff --git a/gr-digital/include/digital/ofdm_cyclic_prefixer.h b/gr-digital/include/digital/ofdm_cyclic_prefixer.h index 551d1ee834..6292d62697 100644 --- a/gr-digital/include/digital/ofdm_cyclic_prefixer.h +++ b/gr-digital/include/digital/ofdm_cyclic_prefixer.h @@ -1,6 +1,6 @@ /* -*- c++ -*- */ -/* - * Copyright 2004-2006,2011,2012 Free Software Foundation, Inc. +/* + * Copyright 2013 Free Software Foundation, Inc. * * This file is part of GNU Radio * @@ -24,34 +24,48 @@ #define INCLUDED_DIGITAL_OFDM_CYCLIC_PREFIXER_H #include <digital/api.h> -#include <gr_sync_interpolator.h> +#include <gr_tagged_stream_block.h> namespace gr { namespace digital { - + /*! - * \brief adds a cyclic prefix vector to an input size long ofdm - * symbol(vector) and converts vector to a stream output_size - * long. + * \brief Adds a cyclic prefix and performs pulse shaping on OFDM symbols. * \ingroup ofdm_blk + * + * Input: OFDM symbols (in the time domain, i.e. after the IFFT). Optionally, + * entire frames can be processed. In this case, \p len_tag_key must be + * specified which holds the key of the tag that denotes how + * many OFDM symbols are in a frame. + * Output: A stream of (scalar) complex symbols, which include the cyclic prefix + * and the pulse shaping. + * Note: If complete frames are processed, and \p rolloff_len is greater + * than zero, the final OFDM symbol is followed by the delay line of + * the pulse shaping. + * + * The pulse shape is a raised cosine in the time domain. */ - class DIGITAL_API ofdm_cyclic_prefixer : virtual public gr_sync_interpolator + class DIGITAL_API ofdm_cyclic_prefixer : virtual public gr_tagged_stream_block { - public: - // gr::digital::ofdm_cyclic_prefixer::sptr + public: typedef boost::shared_ptr<ofdm_cyclic_prefixer> sptr; /*! - * Make an OFDM cyclic prefix adder block. - * - * \param input_size size of the input symbol - * \param output_size output of the symbol - * (CP len = output_size - input_size) + * \param input_size FFT length (i.e. length of the OFDM symbols) + * \param output_size FFT length + cyclic prefix length (in samples) + * \param rolloff_len Length of the rolloff flank in samples + * \param len_tag_key For framed processing the key of the length tag */ - static sptr make(size_t input_size, size_t output_size); + static sptr make( + size_t input_size, + size_t output_size, + int rolloff_len=0, + const std::string &len_tag_key="" + ); }; - } /* namespace digital */ -} /* namespace gr */ + } // namespace digital +} // namespace gr #endif /* INCLUDED_DIGITAL_OFDM_CYCLIC_PREFIXER_H */ + |