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)
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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_CLOCK_RECOVERY_MM_FF_H
24 #define INCLUDED_GR_CLOCK_RECOVERY_MM_FF_H
30 class gri_mmse_fir_interpolator;
32 class gr_clock_recovery_mm_ff;
33 typedef boost::shared_ptr<gr_clock_recovery_mm_ff> gr_clock_recovery_mm_ff_sptr;
36 gr_clock_recovery_mm_ff_sptr
37 gr_make_clock_recovery_mm_ff (float omega, float gain_omega, float mu, float gain_mu,
38 float omega_relative_limit=0.001);
41 * \brief Mueller and Müller (M&M) based clock recovery block with float input, float output.
44 * This implements the Mueller and Müller (M&M) discrete-time error-tracking synchronizer.
46 * See "Digital Communication Receivers: Synchronization, Channel
47 * Estimation and Signal Processing" by Heinrich Meyr, Marc Moeneclaey, & Stefan Fechtel.
50 class gr_clock_recovery_mm_ff : public gr_block
53 ~gr_clock_recovery_mm_ff ();
54 void forecast(int noutput_items, gr_vector_int &ninput_items_required);
55 int general_work (int noutput_items,
56 gr_vector_int &ninput_items,
57 gr_vector_const_void_star &input_items,
58 gr_vector_void_star &output_items);
59 float mu() const { return d_mu;}
60 float omega() const { return d_omega;}
61 float gain_mu() const { return d_gain_mu;}
62 float gain_omega() const { return d_gain_omega;}
64 void set_gain_mu (float gain_mu) { d_gain_mu = gain_mu; }
65 void set_gain_omega (float gain_omega) { d_gain_omega = gain_omega; }
66 void set_mu (float mu) { d_mu = mu; }
67 void set_omega (float omega){
69 d_min_omega = omega*(1.0 - d_omega_relative_limit);
70 d_max_omega = omega*(1.0 + d_omega_relative_limit);
71 d_omega_mid = 0.5*(d_min_omega+d_max_omega);
75 gr_clock_recovery_mm_ff (float omega, float gain_omega, float mu, float gain_mu,
76 float omega_relative_limit);
79 float d_mu; // fractional sample position [0.0, 1.0]
80 float d_omega; // nominal frequency
81 float d_min_omega; // minimum allowed omega
82 float d_omega_mid; // average omega
83 float d_max_omega; // maximum allowed omega
84 float d_gain_omega; // gain for adjusting omega
85 float d_gain_mu; // gain for adjusting mu
87 gri_mmse_fir_interpolator *d_interp;
89 float d_omega_relative_limit; // used to compute min and max omega
91 friend gr_clock_recovery_mm_ff_sptr
92 gr_make_clock_recovery_mm_ff (float omega, float gain_omega, float mu, float gain_mu,
93 float omega_relative_limit);