pll_carriertracking_cc_impl.cc

/* -*- c++ -*- */
/*
 * Copyright 2006,2010-2013 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.
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include "pll_carriertracking_cc_impl.h"
#include <gnuradio/io_signature.h>
#include <gnuradio/sincos.h>
#include <math.h>
#include <gnuradio/math.h>

namespace gr {
  namespace analog {

#ifndef M_TWOPI
#define M_TWOPI (2.0f*M_PI)
#endif

    pll_carriertracking_cc::sptr
    pll_carriertracking_cc::make(float loop_bw, float max_freq, float min_freq)
    {
      return gnuradio::get_initial_sptr
	(new pll_carriertracking_cc_impl(loop_bw, max_freq, min_freq));
    }

    pll_carriertracking_cc_impl::pll_carriertracking_cc_impl(float loop_bw,
							     float max_freq,
							     float min_freq)
      : sync_block("pll_carriertracking_cc",
		      io_signature::make(1, 1, sizeof(gr_complex)),
		      io_signature::make(1, 1, sizeof(gr_complex))),
	blocks::control_loop(loop_bw, max_freq, min_freq),
	d_locksig(0), d_lock_threshold(0), d_squelch_enable(false)
    {
    }

    pll_carriertracking_cc_impl::~pll_carriertracking_cc_impl()
    {
    }

    float
    pll_carriertracking_cc_impl::mod_2pi(float in)
    {
      if(in>M_PI)
	return in-M_TWOPI;
      else if(in<-M_PI)
	return in+M_TWOPI;
      else
	return in;
    }

    float
    pll_carriertracking_cc_impl::phase_detector(gr_complex sample, float ref_phase)
    {
      float sample_phase;
      //  sample_phase = atan2(sample.imag(),sample.real());
      sample_phase = gr::fast_atan2f(sample.imag(),sample.real());
      return mod_2pi(sample_phase-ref_phase);
    }

    bool
    pll_carriertracking_cc_impl::lock_detector(void)
    {
      return (fabsf(d_locksig) > d_lock_threshold);
    }

    bool
    pll_carriertracking_cc_impl::squelch_enable(bool set_squelch)
    {
      return d_squelch_enable = set_squelch;
    }

    float
    pll_carriertracking_cc_impl::set_lock_threshold(float threshold)
    {
      return d_lock_threshold = threshold;
    }

    int
    pll_carriertracking_cc_impl::work(int noutput_items,
				      gr_vector_const_void_star &input_items,
				      gr_vector_void_star &output_items)
    {
      const gr_complex *iptr = (gr_complex*)input_items[0];
      gr_complex *optr = (gr_complex*)output_items[0];

      float error;
      float t_imag, t_real;

      for(int i = 0; i < noutput_items; i++) {
	gr::sincosf(d_phase, &t_imag, &t_real);
	optr[i] = iptr[i] * gr_complex(t_real, -t_imag);

	error = phase_detector(iptr[i], d_phase);

	advance_loop(error);
	phase_wrap();
	frequency_limit();

	d_locksig = d_locksig * (1.0 - d_alpha) + \
	  d_alpha*(iptr[i].real() * t_real + iptr[i].imag() * t_imag);

	if((d_squelch_enable) && !lock_detector())
	  optr[i] = 0;
      }
      return noutput_items;
    }

    void
    pll_carriertracking_cc_impl::set_loop_bandwidth(float bw)
    {
      blocks::control_loop::set_loop_bandwidth(bw);
    }

    void
    pll_carriertracking_cc_impl::set_damping_factor(float df)
    {
      blocks::control_loop::set_damping_factor(df);
    }

    void
    pll_carriertracking_cc_impl::set_alpha(float alpha)
    {
      blocks::control_loop::set_alpha(alpha);
    }

    void
    pll_carriertracking_cc_impl::set_beta(float beta)
    {
      blocks::control_loop::set_beta(beta);
    }

    void
    pll_carriertracking_cc_impl::set_frequency(float freq)
    {
      blocks::control_loop::set_frequency(freq);
    }

    void
    pll_carriertracking_cc_impl::set_phase(float phase)
    {
      blocks::control_loop::set_phase(phase);
    }

    void
    pll_carriertracking_cc_impl::set_min_freq(float freq)
    {
      blocks::control_loop::set_min_freq(freq);
    }

    void
    pll_carriertracking_cc_impl::set_max_freq(float freq)
    {
      blocks::control_loop::set_max_freq(freq);
    }


    float
    pll_carriertracking_cc_impl::get_loop_bandwidth() const
    {
      return blocks::control_loop::get_loop_bandwidth();
    }

    float
    pll_carriertracking_cc_impl::get_damping_factor() const
    {
      return blocks::control_loop::get_damping_factor();
    }

    float
    pll_carriertracking_cc_impl::get_alpha() const
    {
      return blocks::control_loop::get_alpha();
    }

    float
    pll_carriertracking_cc_impl::get_beta() const
    {
      return blocks::control_loop::get_beta();
    }

    float
    pll_carriertracking_cc_impl::get_frequency() const
    {
      return blocks::control_loop::get_frequency();
    }

    float
    pll_carriertracking_cc_impl::get_phase() const
    {
      return blocks::control_loop::get_phase();
    }

    float
    pll_carriertracking_cc_impl::get_min_freq() const
    {
      return blocks::control_loop::get_min_freq();
    }

    float
    pll_carriertracking_cc_impl::get_max_freq() const
    {
      return blocks::control_loop::get_max_freq();
    }

  } /* namespace analog */
} /* namespace gr */