gr_fxpt_nco.h

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/* -*- c++ -*- */
/*
 * Copyright 2002,2004 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 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_GR_FXPT_NCO_H
#define INCLUDED_GR_FXPT_NCO_H

#include <gr_fxpt.h>
#include <gr_complex.h>

/*!
 * \brief Numerically Controlled Oscillator (NCO)
 * \ingroup misc
 */
class gr_fxpt_nco {
  gr_uint32	d_phase;
  gr_int32	d_phase_inc;

public:
  gr_fxpt_nco () : d_phase (0), d_phase_inc (0) {}

  ~gr_fxpt_nco () {}

  // radians
  void set_phase (float angle) {
    d_phase = gr_fxpt::float_to_fixed (angle);
  }

  void adjust_phase (float delta_phase) {
    d_phase += gr_fxpt::float_to_fixed (delta_phase);
  }

  // angle_rate is in radians / step
  void set_freq (float angle_rate){
    d_phase_inc = gr_fxpt::float_to_fixed (angle_rate);
  }

  // angle_rate is a delta in radians / step
  void adjust_freq (float delta_angle_rate)
  {
    d_phase_inc += gr_fxpt::float_to_fixed (delta_angle_rate);
  }

  // increment current phase angle

  void step () 
  { 
    d_phase += d_phase_inc;
  }

  void step (int n)
  {
    d_phase += d_phase_inc * n;
  }

  // units are radians / step
  float get_phase () const { return gr_fxpt::fixed_to_float (d_phase); }
  float get_freq () const { return gr_fxpt::fixed_to_float (d_phase_inc); }

  // compute sin and cos for current phase angle
  void sincos (float *sinx, float *cosx) const
  {
    *sinx = gr_fxpt::sin (d_phase);
    *cosx = gr_fxpt::cos (d_phase);
  }

  // compute cos and sin for a block of phase angles
  void sincos (gr_complex *output, int noutput_items, double ampl=1.0)
  {
    for (int i = 0; i < noutput_items; i++){
      output[i]   = gr_complex(gr_fxpt::cos (d_phase) * ampl, gr_fxpt::sin (d_phase) * ampl);
      step ();
    }
  }

  // compute sin for a block of phase angles
  void sin (float *output, int noutput_items, double ampl=1.0)
  {
    for (int i = 0; i < noutput_items; i++){
      output[i] = (float)(gr_fxpt::sin (d_phase) * ampl);
      step ();
    }
  }

  // compute cos for a block of phase angles
  void cos (float *output, int noutput_items, double ampl=1.0)
  {
    for (int i = 0; i < noutput_items; i++){
      output[i] = (float)(gr_fxpt::cos (d_phase) * ampl);
      step ();
    }
  }

  // compute sin for a block of phase angles
  void sin (short *output, int noutput_items, double ampl=1.0)
  {
    for (int i = 0; i < noutput_items; i++){
      output[i] = (short)(gr_fxpt::sin (d_phase) * ampl);
      step ();
    }
  }

  // compute cos for a block of phase angles
  void cos (short *output, int noutput_items, double ampl=1.0)
  {
    for (int i = 0; i < noutput_items; i++){
      output[i] = (short)(gr_fxpt::cos (d_phase) * ampl);
      step ();
    }
  }

  // compute sin for a block of phase angles
  void sin (int *output, int noutput_items, double ampl=1.0)
  {
    for (int i = 0; i < noutput_items; i++){
      output[i] = (int)(gr_fxpt::sin (d_phase) * ampl);
      step ();
    }
  }

  // compute cos for a block of phase angles
  void cos (int *output, int noutput_items, double ampl=1.0)
  {
    for (int i = 0; i < noutput_items; i++){
      output[i] = (int)(gr_fxpt::cos (d_phase) * ampl);
      step ();
    }
  }

  // compute cos or sin for current phase angle
  float cos () const { return gr_fxpt::cos (d_phase); }
  float sin () const { return gr_fxpt::sin (d_phase); }
};

#endif /* INCLUDED_GR_FXPT_NCO_H */