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/* -*- c++ -*- */
/*
* Copyright 2002 Free Software Foundation, Inc.
*
* This file is part of GNU Radio
*
* GNU Radio is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 3, or (at your option)
* any later version.
*
* GNU Radio is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GNU Radio; see the file COPYING. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street,
* Boston, MA 02110-1301, USA.
*/
#include <math.h>
#include <atsci_fake_single_viterbi.h>
#include <iostream>
#include <algorithm>
using std::cerr;
using std::cout;
void
atsci_fake_single_viterbi::reset()
{
post_coder_state = 0;
}
atsci_fake_single_viterbi::atsci_fake_single_viterbi()
{
reset();
}
/*
* implement simple slicer and post coder
*/
char
atsci_fake_single_viterbi::decode (float input)
{
int y2, y1;
if (input < -4){
y2 = 0;
y1 = 0;
}
else if (input < 0){
y2 = 0;
y1 = 1;
}
else if (input < 4){
y2 = 1;
y1 = 0;
}
else {
y2 = 1;
y1 = 1;
}
int x1 = y1;
int x2 = y2 ^ post_coder_state;
post_coder_state = y2;
return (x2 << 1) | x1;
}
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