1 files changed, 160 insertions, 0 deletions
diff --git a/gr-analog/include/analog/agc2.h b/gr-analog/include/analog/agc2.h
new file mode 100644
index 000000000..75a203e9f
--- /dev/null
+++ b/gr-analog/include/analog/agc2.h
@@ -0,0 +1,160 @@
+/* -*- 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_AGC2_H
+#define INCLUDED_ANALOG_AGC2_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 Power the absolute value of the complex number is used.
+       */
+      class ANALOG_API agc2_cc
+      {
+      public:
+	agc2_cc(float attack_rate = 1e-1, float decay_rate = 1e-2,
+		float reference = 1.0,
+		float gain = 1.0, float max_gain = 0.0)
+	  : _attack_rate(attack_rate), _decay_rate(decay_rate),
+	  _reference(reference),
+	  _gain(gain), _max_gain(max_gain) {};
+
+	float decay_rate() const  { return _decay_rate; }
+	float attack_rate() const { return _attack_rate; }
+	float reference() const   { return _reference; }
+	float gain() const        { return _gain;  }
+	float max_gain() const     { return _max_gain; }
+
+	void set_decay_rate(float rate) { _decay_rate = rate; }
+	void set_attack_rate(float rate) { _attack_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;
+
+	  float tmp = -_reference + sqrt(output.real()*output.real() +
+					 output.imag()*output.imag());
+	  float rate = _decay_rate;
+	  if((tmp) > _gain) {
+	    rate = _attack_rate;
+	  }
+	  _gain -= tmp*rate;
+
+	  // Not sure about this; will blow up if _gain < 0 (happens
+	  // when rates are too high), but is this the solution?
+	  if(_gain < 0.0)
+	    _gain = 10e-5;
+
+	  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 _attack_rate;	// attack rate for fast changing signals
+	float _decay_rate;	// decay rate for slow changing signals
+	float _reference;	// reference value
+	float _gain;		// current gain
+	float _max_gain;	// max allowable gain
+      };
+
+
+      class ANALOG_API agc2_ff
+      {
+      public:
+	agc2_ff(float attack_rate = 1e-1, float decay_rate = 1e-2,
+		float reference = 1.0,
+		float gain = 1.0, float max_gain = 0.0)
+	  : _attack_rate(attack_rate), _decay_rate(decay_rate),
+	  _reference(reference),
+	  _gain(gain), _max_gain(max_gain) {};
+
+	float attack_rate() const { return _attack_rate; }
+	float decay_rate() const  { return _decay_rate; }
+	float reference() const   { return _reference; }
+	float gain() const        { return _gain;  }
+	float max_gain() const    { return _max_gain; }
+
+	void set_attack_rate(float rate) { _attack_rate = rate; }
+	void set_decay_rate(float rate) { _decay_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;
+
+	  float tmp = (fabsf(output)) - _reference;
+	  float rate = _decay_rate;
+	  if(fabsf(tmp) > _gain) {
+	    rate = _attack_rate;
+	  }
+	  _gain -= tmp*rate;
+
+	  // Not sure about this
+	  if(_gain < 0.0)
+	    _gain = 10e-5;
+
+	  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 _attack_rate;     // attack_rate for fast changing signals
+	float _decay_rate;	// decay rate for slow changing signals
+	float _reference;	// reference value
+	float _gain;		// current gain
+	float _max_gain;	// maximum gain
+      };
+      
+    } /* namespace kernel */
+  } /* namespace analog */
+} /* namespace gr */
+
+#endif /* INCLUDED_ANALOG_AGC2_H */