/* -*- c++ -*- */

/*

 * Copyright 2006 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_PWR_SQUELCH_CC_H

#define INCLUDED_GR_PWR_SQUELCH_CC_H

#include <cmath>

#include <gr_squelch_base_cc.h>

#include <gr_single_pole_iir.h>

class gr_pwr_squelch_cc;

typedef boost::shared_ptr<gr_pwr_squelch_cc> gr_pwr_squelch_cc_sptr;

gr_pwr_squelch_cc_sptr 

gr_make_pwr_squelch_cc(double db, double alpha = 0.0001, int ramp=0, bool gate=false);

/*!

 * \brief gate or zero output when input power below threshold

 * \ingroup block

 */

class gr_pwr_squelch_cc : public gr_squelch_base_cc

{

private:

  double d_threshold;

  double d_pwr;

  gr_single_pole_iir<double,double,double> d_iir;

  friend gr_pwr_squelch_cc_sptr gr_make_pwr_squelch_cc(double db, double alpha, int ramp, bool gate);

  gr_pwr_squelch_cc(double db, double alpha, int ramp, bool gate);

protected:

  virtual void update_state(const gr_complex &in);

  virtual bool mute() const { return d_pwr < d_threshold; }

public:

  std::vector<float> squelch_range() const;

  double threshold() const { return 10*log10(d_threshold); }

  void set_threshold(double db) { d_threshold = std::pow(10.0, db/10); }

  void set_alpha(double alpha) { d_iir.set_taps(alpha); }

};

#endif /* INCLUDED_GR_PWR_SQUELCH_CC_H */