GNU Radio Manual and C++ API Reference 3.7.14.0
The Free & Open Software Radio Ecosystem
fs_correlator_naive_impl.h
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1/* -*- c++ -*- */
2/*
3 * Copyright 2002 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,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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,
20 * Boston, MA 02110-1301, USA.
21 */
22
23#ifndef _ATSC_FS_CORRELATOR_NAIVE_H_
24#define _ATSC_FS_CORRELATOR_NAIVE_H_
25
26#include <gnuradio/atsc/api.h>
28
29/*!
30 * \brief Naive concrete implementation of field sync correlator
31 */
33{
34
35private:
36 static const int SRSIZE = 1024; // must be power of two
37 int d_index; // points at oldest sample
38 float d_sample_sr[SRSIZE]; // sample shift register
39 unsigned char d_bit_sr[SRSIZE]; // binary decision shift register
40
41 static const int OFFSET_511 = 0; // offset to PN 511 pattern
42 static const int LENGTH_511 = 511 + 4; // length of PN 511 pattern (+ 4 seg sync)
43 static const int OFFSET_2ND_63 = 578; // offset to second PN 63 pattern
44 static const int LENGTH_2ND_63 = 63; // length of PN 63 pattern
45
46 static unsigned char s_511[LENGTH_511]; // PN 511 pattern
47 static unsigned char s_63[LENGTH_2ND_63]; // PN 63 pattern
48
49 inline static int wrap(int index) { return index & (SRSIZE - 1); }
50 inline static int incr(int index) { return wrap(index + 1); }
51 inline static int decr(int index) { return wrap(index - 1); }
52
53public:
54 // CREATORS
57
58 // MANIPULATORS
59 virtual void reset();
60 void filter(float input_sample, float* output_sample, float* output_tag);
61
62 // ACCESSORS
63
64 //! return delay in samples from input to output
65 int delay() const;
66};
67
68
69#endif /* _ATSC_FS_CORRELATOR_NAIVE_H_ */
Naive concrete implementation of field sync correlator.
Definition: fs_correlator_naive_impl.h:33
int delay() const
return delay in samples from input to output
void filter(float input_sample, float *output_sample, float *output_tag)
abstract base class for ATSC field sync correlator
Definition: fs_correlator_impl.h:49
#define ATSC_API
Definition: gr-atsc/include/gnuradio/atsc/api.h:30