GNU Radio Manual and C++ API Reference  3.7.13.4
The Free & Open Software Radio Ecosystem
pwr_squelch_ff.h
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1 /* -*- c++ -*- */
2 /*
3  * Copyright 2006,2012 Free Software Foundation, Inc.
4  *
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22 
23 #ifndef INCLUDED_ANALOG_PWR_SQUELCH_FF_H
24 #define INCLUDED_ANALOG_PWR_SQUELCH_FF_H
25 
26 #include <gnuradio/analog/api.h>
28 #include <cmath>
29 
30 namespace gr {
31  namespace analog {
32 
33  /*!
34  * \brief gate or zero output when input power below threshold
35  * \ingroup level_controllers_blk
36  */
38  public squelch_base_ff, virtual public block
39  {
40  protected:
41  virtual void update_state(const float &in) = 0;
42  virtual bool mute() const = 0;
43 
44  public:
45  // gr::analog::pwr_squelch_ff::sptr
46  typedef boost::shared_ptr<pwr_squelch_ff> sptr;
47 
48  /*!
49  * \brief Make power-based squelch block.
50  *
51  * \param db threshold (in dB) for power squelch
52  * \param alpha Gain of averaging filter. Defaults to 0.0001.
53  * \param ramp sets response characteristic. Defaults to 0.
54  * \param gate if true, no output if no squelch tone.
55  * if false, output 0's if no squelch tone (default).
56  *
57  * The block will emit a tag with the key pmt::intern("squelch_sob")
58  * with the value of pmt::PMT_NIL on the first item it passes, and with
59  * the key pmt::intern("squelch:eob") on the last item it passes.
60  */
61  static sptr make(double db, double alpha=0.0001,
62  int ramp=0, bool gate=false);
63 
64  virtual std::vector<float> squelch_range() const = 0;
65 
66  virtual double threshold() const = 0;
67  virtual void set_threshold(double db) = 0;
68  virtual void set_alpha(double alpha) = 0;
69 
70  virtual int ramp() const = 0;
71  virtual void set_ramp(int ramp) = 0;
72  virtual bool gate() const = 0;
73  virtual void set_gate(bool gate) = 0;
74  virtual bool unmuted() const = 0;
75  };
76 
77  } /* namespace analog */
78 } /* namespace gr */
79 
80 #endif /* INCLUDED_ANALOG_PWR_SQUELCH_FF_H */
basic squelch block; to be subclassed for other squelches.
Definition: squelch_base_ff.h:36
boost::shared_ptr< pwr_squelch_ff > sptr
Definition: pwr_squelch_ff.h:46
Include this header to use the message passing features.
Definition: logger.h:695
#define ANALOG_API
Definition: gr-analog/include/gnuradio/analog/api.h:30
The abstract base class for all &#39;terminal&#39; processing blocks.A signal processing flow is constructed ...
Definition: block.h:65
gate or zero output when input power below threshold
Definition: pwr_squelch_ff.h:37