viterbi_detector.h
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/* -*- c++ -*- */
/*
* @file
* @author (C) 2009 Piotr Krysik <ptrkrysik@gmail.com>
* @section LICENSE
*
* Gr-gsm 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.
*
* Gr-gsm 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 gr-gsm; see the file COPYING. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street,
* Boston, MA 02110-1301, 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.
*/
#ifndef INCLUDED_VITERBI_DETECTOR_H
#define INCLUDED_VITERBI_DETECTOR_H
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);
#endif /* INCLUDED_VITERBI_DETECTOR_H */
viterbi_detector
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)