GNU Radio 3.7.1-52 C++ API
channel_model.h
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1 /* -*- c++ -*- */
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3  * Copyright 2009,2012 Free Software Foundation, Inc.
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22 
23 #ifndef INCLUDED_CHANNELS_CHANNEL_MODEL_H
24 #define INCLUDED_CHANNELS_CHANNEL_MODEL_H
25 
26 #include <gnuradio/channels/api.h>
27 #include <gnuradio/hier_block2.h>
28 #include <gnuradio/types.h>
29 
30 namespace gr {
31  namespace channels {
32 
33  /*!
34  * \brief channel simulator
35  * \ingroup channel_models_blk
36  *
37  * \details
38  * This block implements a basic channel model simulator that can
39  * be used to help evaluate, design, and test various signals,
40  * waveforms, and algorithms. This model allows the user to set
41  * the voltage of an AWGN noise source, a (normalized) frequency
42  * offset, a sample timing offset, and a noise seed to randomize
43  * the AWGN noise source.
44  *
45  * Multipath can be approximated in this model by using a FIR
46  * filter representation of a multipath delay profile..
47  */
48  class CHANNELS_API channel_model : virtual public hier_block2
49  {
50  public:
51  // gr::channels::channel_model::sptr
53 
54  /*! \brief Build the channel simulator.
55  *
56  * \param noise_voltage The AWGN noise level as a voltage (to be
57  * calculated externally to meet, say, a
58  * desired SNR).
59  * \param frequency_offset The normalized frequency offset. 0 is
60  * no offset; 0.25 would be, for a digital
61  * modem, one quarter of the symbol rate.
62  * \param epsilon The sample timing offset to emulate the
63  * different rates between the sample clocks of
64  * the transmitter and receiver. 1.0 is no difference.
65  * \param taps Taps of a FIR filter to emulate a multipath delay profile.
66  * \param noise_seed A random number generator seed for the noise source.
67  */
68  static sptr make(double noise_voltage=0.0,
69  double frequency_offset=0.0,
70  double epsilon=1.0,
71  const std::vector<gr_complex> &taps=std::vector<gr_complex>(1,1),
72  double noise_seed=0);
73 
74  virtual void set_noise_voltage(double noise_voltage) = 0;
75  virtual void set_frequency_offset(double frequency_offset) = 0;
76  virtual void set_taps(const std::vector<gr_complex> &taps) = 0;
77  virtual void set_timing_offset(double epsilon) = 0;
78 
79  virtual double noise_voltage() const = 0;
80  virtual double frequency_offset() const = 0;
81  virtual std::vector<gr_complex> taps() const = 0;
82  virtual double timing_offset() const = 0;
83  };
84 
85  } /* namespace channels */
86 } /* namespace gr */
87 
88 #endif /* INCLUDED_CHANNELS_CHANNEL_MODEL_H */