GNU Radio 3.7.2git-29-g7516b6dd C++ API
constellation_receiver_cb.h
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1 /* -*- c++ -*- */
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22 
23 #ifndef INCLUDED_DIGITAL_CONSTELLATION_RECEIVER_CB_H
24 #define INCLUDED_DIGITAL_CONSTELLATION_RECEIVER_CB_H
25 
26 #include <gnuradio/digital/api.h>
28 #include <gnuradio/block.h>
29 
30 namespace gr {
31  namespace digital {
32 
33  /*!
34  * \brief This block makes hard decisions about the received
35  * symbols (using a constellation object) and also fine tunes
36  * phase synchronization.
37  *
38  * \details
39  *
40  * The phase and frequency synchronization are based on a Costas
41  * loop that finds the error of the incoming signal point compared
42  * to its nearest constellation point. The frequency and phase of
43  * the NCO are updated according to this error.
44  */
46  : virtual public block
47  {
48  public:
49  // gr::digital::constellation_receiver_cb::sptr
51 
52  /*!
53  * \brief Constructor to synchronize incoming M-PSK symbols
54  *
55  * \param constellation constellation of points for generic modulation
56  * \param loop_bw Loop bandwidth of the Costas Loop (~ 2pi/100)
57  * \param fmin minimum normalized frequency value the loop can achieve
58  * \param fmax maximum normalized frequency value the loop can achieve
59  *
60  * The constructor chooses which phase detector and decision
61  * maker to use in the work loop based on the value of M.
62  */
64  float loop_bw, float fmin, float fmax);
65 
66  virtual void phase_error_tracking(float phase_error) = 0;
67  };
68 
69  } /* namespace digital */
70 } /* namespace gr */
71 
72 #endif /* INCLUDED_DIGITAL_CONSTELLATION_RECEIVER_CB_H */