3 * Copyright 2004 Free Software Foundation, Inc.
5 * This file is part of GNU Radio
7 * GNU Radio is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 3, or (at your option)
12 * GNU Radio is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with GNU Radio; see the file COPYING. If not, write to
19 * the Free Software Foundation, Inc., 51 Franklin Street,
20 * Boston, MA 02110-1301, USA.
23 #ifndef INCLUDED_GR_PLL_FREQDET_CF_H
24 #define INCLUDED_GR_PLL_FREQDET_CF_H
26 #include <gr_sync_block.h>
28 class gr_pll_freqdet_cf;
29 typedef boost::shared_ptr<gr_pll_freqdet_cf> gr_pll_freqdet_cf_sptr;
31 gr_pll_freqdet_cf_sptr gr_make_pll_freqdet_cf (float alpha, float beta,
32 float max_freq, float min_freq);
34 * \brief Implements a PLL which locks to the input frequency and outputs
35 * an estimate of that frequency. Useful for FM Demod.
38 * input: stream of complex; output: stream of floats
40 * This PLL locks onto a [possibly noisy] reference carrier on
41 * the input and outputs an estimate of that frequency in radians per sample.
42 * All settings max_freq and min_freq are in terms of radians per sample,
43 * NOT HERTZ. Alpha is the phase gain (first order, units of radians per radian)
44 * and beta is the frequency gain (second order, units of radians per sample per radian)
45 * \sa gr_pll_refout_cc, gr_pll_carriertracking_cc
48 class gr_pll_freqdet_cf : public gr_sync_block
50 friend gr_pll_freqdet_cf_sptr gr_make_pll_freqdet_cf (float alpha, float beta,
51 float max_freq, float min_freq);
53 float d_alpha,d_beta,d_max_freq,d_min_freq,d_phase,d_freq;
54 gr_pll_freqdet_cf (float alpha, float beta, float max_freq, float min_freq);
56 int work (int noutput_items,
57 gr_vector_const_void_star &input_items,
58 gr_vector_void_star &output_items);
60 float mod_2pi (float in);
61 float phase_detector(gr_complex sample,float ref_phase);