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/***************************************************************************
* Copyright (C) 2008 by Piotr Krysik *
* pkrysik@stud.elka.pw.edu.pl *
* *
* This program 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 2 of the License, or *
* (at your option) any later version. *
* *
* This program 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 this program; if not, write to the *
* Free Software Foundation, Inc., *
* 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. *
***************************************************************************/
/*
** viterbi_detector:
** This part does the detection of received sequnece.
** Employed algorithm is viterbi Maximum Likehood Sequence Estimation.
** At this moment it gives hard decisions on the output, but
** it was designed with soft decisions in mind.
**
** SYNTAX: void viterbi_detector(
** const gr_complex * input,
** unsigned int samples_num,
** gr_complex * rhh,
** unsigned int start_state,
** const unsigned int * stop_states,
** unsigned int stops_num,
** float * output)
**
** INPUT: input: Complex received signal afted matched filtering.
** samples_num: Number of samples in the input table.
** rhh: The autocorrelation of the estimated channel
** impulse response.
** start_state: Number of the start point. In GSM each burst
** starts with sequence of three bits (0,0,0) which
** indicates start point of the algorithm.
** stop_states: Table with numbers of possible stop states.
** stops_num: Number of possible stop states
**
**
** OUTPUT: output: Differentially decoded hard output of the algorithm:
** -1 for logical "0" and 1 for logical "1"
**
** SUB_FUNC: none
**
** TEST(S): Tested with real world normal burst.
*/
void viterbi_detector(const gr_complex * input, unsigned int samples_num, gr_complex * rhh, unsigned int start_state, const unsigned int * stop_states, unsigned int stops_num, float * output);
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