GNU Radio Manual and C++ API Reference 3.7.14.0
The Free & Open Software Radio Ecosystem
fs_checker_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#ifndef _ATSC_FS_CHECKER_H_
23#define _ATSC_FS_CHECKER_H_
24
25#include <gnuradio/atsc/api.h>
27
28/*!
29 * \brief abstract base class for ATSC field sync checker
30 *
31 * Processes input samples one at a time looking for
32 * an occurrence of either the field sync 1 or field sync 2 pattern.
33 *
34 * Note that unlike atsci_fs_correlator, this class uses the symbol_num in
35 * input_tag to avoid having to test each symbol position.
36 *
37 * For each sample processed, an output sample and an output tag are produced.
38 * The output samples are identical to the input samples but are delayed by
39 * a number of samples given by \p delay(). The output tag associated with
40 * the the given output sample indicates whether this sample is the beginning
41 * of one of the field syncs or is an ordinary sample. The tags are defined in
42 * atsci_sync_tag.h.
43 *
44 * For ease of use, the field sync patterns are defined to begin with the
45 * first symbol of the 4 symbol data segment sync pattern that immediately
46 * proceeds the actual PN 511 code. This makes it easier for downstream code
47 * to determine the location of data segment syncs merely by counting. They'll
48 * occur every 832 samples assuming everything is working.
49 */
50
52{
53
54public:
55 // CREATORS
57 virtual ~atsci_fs_checker() = 0;
58
59 // MANIPULATORS
60 virtual void reset() = 0;
61 virtual void filter(float input_sample,
62 atsc::syminfo input_tag,
63 float* output_sample,
64 atsc::syminfo* output_tag) = 0;
65
66 // ACCESSORS
67
68 //! return delay in samples from input to output
69 virtual int delay() const = 0;
70};
71
72#endif /* _ATSC_FS_CHECKER_H_ */
abstract base class for ATSC field sync checker
Definition: fs_checker_impl.h:52
virtual void reset()=0
virtual ~atsci_fs_checker()=0
virtual void filter(float input_sample, atsc::syminfo input_tag, float *output_sample, atsc::syminfo *output_tag)=0
virtual int delay() const =0
return delay in samples from input to output
#define ATSC_API
Definition: gr-atsc/include/gnuradio/atsc/api.h:30
Definition: syminfo_impl.h:31