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Diffstat (limited to 'gr-analog/include/analog/agc.h')
-rw-r--r-- | gr-analog/include/analog/agc.h | 136 |
1 files changed, 136 insertions, 0 deletions
diff --git a/gr-analog/include/analog/agc.h b/gr-analog/include/analog/agc.h new file mode 100644 index 000000000..92d777fa1 --- /dev/null +++ b/gr-analog/include/analog/agc.h @@ -0,0 +1,136 @@ +/* -*- c++ -*- */ +/* + * Copyright 2006,2012 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_ANALOG_AGC_H +#define INCLUDED_ANALOG_AGC_H + +#include <analog/api.h> +#include <gr_complex.h> +#include <math.h> + +namespace gr { + namespace analog { + namespace kernel { + + /*! + * \brief high performance Automatic Gain Control class for complex signals. + * + * For Power the absolute value of the complex number is used. + */ + class ANALOG_API agc_cc + { + public: + agc_cc(float rate = 1e-4, float reference = 1.0, + float gain = 1.0, float max_gain = 0.0) + : _rate(rate), _reference(reference), + _gain(gain), _max_gain(max_gain) {}; + + virtual ~agc_cc() {}; + + float rate() const { return _rate; } + float reference() const { return _reference; } + float gain() const { return _gain; } + float max_gain() const { return _max_gain; } + + void set_rate(float rate) { _rate = rate; } + void set_reference(float reference) { _reference = reference; } + void set_gain(float gain) { _gain = gain; } + void set_max_gain(float max_gain) { _max_gain = max_gain; } + + gr_complex scale(gr_complex input) + { + gr_complex output = input * _gain; + + _gain += _rate * (_reference - sqrt(output.real()*output.real() + + output.imag()*output.imag())); + if(_max_gain > 0.0 && _gain > _max_gain) { + _gain = _max_gain; + } + return output; + } + + void scaleN(gr_complex output[], const gr_complex input[], unsigned n) + { + for(unsigned i = 0; i < n; i++) { + output[i] = scale (input[i]); + } + } + + protected: + float _rate; // adjustment rate + float _reference; // reference value + float _gain; // current gain + float _max_gain; // max allowable gain + }; + + /*! + * \brief high performance Automatic Gain Control class for float signals. + * + * Power is approximated by absolute value + */ + class ANALOG_API agc_ff + { + public: + agc_ff(float rate = 1e-4, float reference = 1.0, + float gain = 1.0, float max_gain = 0.0) + : _rate(rate), _reference(reference), _gain(gain), + _max_gain(max_gain) {}; + + ~agc_ff() {}; + + float rate () const { return _rate; } + float reference () const { return _reference; } + float gain () const { return _gain; } + float max_gain () const { return _max_gain; } + + void set_rate (float rate) { _rate = rate; } + void set_reference (float reference) { _reference = reference; } + void set_gain (float gain) { _gain = gain; } + void set_max_gain (float max_gain) { _max_gain = max_gain; } + + float scale (float input) + { + float output = input * _gain; + _gain += (_reference - fabsf (output)) * _rate; + if(_max_gain > 0.0 && _gain > _max_gain) + _gain = _max_gain; + return output; + } + + void scaleN(float output[], const float input[], unsigned n) + { + for(unsigned i = 0; i < n; i++) + output[i] = scale (input[i]); + } + + protected: + float _rate; // adjustment rate + float _reference; // reference value + float _gain; // current gain + float _max_gain; // maximum gain + }; + + } /* namespace kernel */ + } /* namespace analog */ +} /* namespace gr */ + +#endif /* INCLUDED_ANALOG_AGC_H */ |