gr_sync_block.h

gnuradio软件无线电源程序.现在的手机多基于软件无线电

/* -*- c++ -*- */
/*
 * Copyright 2004 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 2, 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., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */

#ifndef INCLUDED_GR_SYNC_BLOCK_H
#define INCLUDED_GR_SYNC_BLOCK_H

#include <gr_block.h>

/*!
 * \brief synchronous 1:1 input to output with history
 * \ingroup block
 *
 * Override work to provide the signal processing implementation.
 */
class gr_sync_block : public gr_block
{
 private:
  unsigned	d_history;

 protected:

  gr_sync_block (const std::string &name,
		 gr_io_signature_sptr input_signature,
		 gr_io_signature_sptr output_signature);

 public:

  /*!
   * Assume block computes y_i = f(x_i, x_i-1, x_i-2, x_i-3...)
   * History is the number of x_i's that are examined to produce one y_i.
   * This comes in handy for FIR filters, where we use history to
   * ensure that our input contains the appropriate "history" for the
   * filter.   History should be equal to the number of filter taps.
   */
  unsigned history () const { return d_history; }
  void  set_history (unsigned history) { d_history = history; }
  
  /*!
   * \brief just like gr_block::general_work, only this arranges to call consume_each for you
   *
   * The user must override work to define the signal processing code
   */
  virtual int work (int noutput_items,
		    gr_vector_const_void_star &input_items,
		    gr_vector_void_star &output_items) = 0;
  

  // gr_sync_block overrides these to assist work
  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);
};
 
#endif /* INCLUDED_GR_SYNC_BLOCK_H */