GNU Radio C++ API
gr_vco.h
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1 /* -*- c++ -*- */
2 /*
3  * Copyright 2005 Free Software Foundation, Inc.
4  *
5  * This file is part of GNU Radio
6  *
7  * GNU Radio is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 3, or (at your option)
10  * any later version.
11  *
12  * GNU Radio is distributed in the hope that it will be useful,
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14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with GNU Radio; see the file COPYING. If not, write to
19  * the Free Software Foundation, Inc., 51 Franklin Street,
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21  */
22 #ifndef _GR_VCO_H_
23 #define _GR_VCO_H_
24 
25 
26 #include <vector>
27 #include <gr_sincos.h>
28 #include <cmath>
29 #include <gr_complex.h>
30 
31 /*!
32  * \brief base class template for Voltage Controlled Oscillator (VCO)
33  * \ingroup misc
34  */
35 
36 //FIXME Eventually generalize this to fixed point
37 
38 template<class o_type, class i_type>
39 class gr_vco {
40 public:
41  gr_vco () : d_phase (0) {}
42 
43  virtual ~gr_vco () {}
44 
45  // radians
46  void set_phase (double angle) {
47  d_phase = angle;
48  }
49 
50  void adjust_phase (double delta_phase) {
51  d_phase += delta_phase;
52  if (fabs (d_phase) > M_PI){
53 
54  while (d_phase > M_PI)
55  d_phase -= 2*M_PI;
56 
57  while (d_phase < -M_PI)
58  d_phase += 2*M_PI;
59  }
60  }
61 
62  double get_phase () const { return d_phase; }
63 
64  // compute sin and cos for current phase angle
65  void sincos (float *sinx, float *cosx) const;
66 
67  // compute cos or sin for current phase angle
68  float cos () const { return std::cos (d_phase); }
69  float sin () const { return std::sin (d_phase); }
70 
71  // compute a block at a time
72  void cos (float *output, const float *input, int noutput_items, double k, double ampl = 1.0);
73 
74 protected:
75  double d_phase;
76 };
77 
78 template<class o_type, class i_type>
79 void
80 gr_vco<o_type,i_type>::sincos (float *sinx, float *cosx) const
81 {
82  gr_sincosf (d_phase, sinx, cosx);
83 }
84 
85 template<class o_type, class i_type>
86 void
87 gr_vco<o_type,i_type>::cos (float *output, const float *input, int noutput_items, double k, double ampl)
88 {
89  for (int i = 0; i < noutput_items; i++){
90  output[i] = cos() * ampl;
91  adjust_phase(input[i] * k);
92  }
93 }
94 #endif /* _GR_VCO_H_ */