1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
|
/* -*- c++ -*- */
/*
* Copyright 2002,2011 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.
*/
#ifndef INCLUDED_TRELLIS_FSM_H
#define INCLUDED_TRELLIS_FSM_H
#include <vector>
#include <iosfwd>
/*!
* \brief Finite State Machine Specification class.
*
* An instance of this class represents a finite state machine specification (FSMS)
* rather than the FSM itself. It particular the state of the FSM
* is not stored within an instance of this class.
*/
class fsm {
private:
// Input alphabet cardinality.
int d_I;
// Number of states.
int d_S;
// Output alphabet cardinality.
int d_O;
// NS means Next State.
// next_state = d_NS[current_state * d_I + input_symbol]
std::vector<int> d_NS;
// OS means Output Symbol.
// output_symbol = d_OS[current_state * d_I + input_symbol]
std::vector<int> d_OS;
// PS means Previous State.
std::vector< std::vector<int> > d_PS;
// PI means Previous Input Symbol.
// d_PS[current_state][k] and d_PI[current_state][k], is a pair of the form
// (previous_state, previous_input_symbol) that could have produced the
// current state.
std::vector< std::vector<int> > d_PI;
// TM means Termination matrix.
// d_TMl[s*d_S+es] is the shortest number of steps to get from state s to
// state es.
std::vector<int> d_TMl;
// d_TMi[s*d_S+es] is the input symbol required to set off on the shortest
// path from state s to es.
std::vector<int> d_TMi;
void generate_PS_PI ();
void generate_TM ();
bool find_es(int es);
public:
/*!
* \brief Constructor to create an uninitialized FSMS.
*/
fsm();
/*!
* \brief Constructor to copy an FSMS.
*/
fsm(const fsm &FSM);
/*!
* \brief Constructor to to create an FSMS.
*
* \param I The number of possible input symbols.
* \param S The number of possible FSM states.
* \param O The number of possible output symbols.
* \param NS A mapping from (current state, input symbol) to next state.
* next_state = NS[current_state * I + input_symbol]
* \param OS A mapping from (current state, input symbol) to output symbol.
* output_symbol = OS[current_state * I + input_symbol]
*
*/
fsm(int I, int S, int O, const std::vector<int> &NS, const std::vector<int> &OS);
/*!
* \brief Constructor to create an FSMS from file contents.
*
* \param name filename
*
*/
fsm(const char *name);
/*!
* \brief Creates an FSMS from the generator matrix of a (n, k) binary convolutional code.
*
* \param k ???
* \param n ???
* \param G ???
*
*/
fsm(int k, int n, const std::vector<int> &G);
/*!
* \brief Creates an FSMS describing ISI.
*
* \param mod_size modulation size
* \param ch_lenth channel length
*
*/
fsm(int mod_size, int ch_length);
/*!
* \brief Creates an FSMS describing the trellis for a CPM.
*
* \param P ???? h=K/P (relatively prime)
* \param M alphabet size
* \param L pulse duration
*
* This FSM is based on the paper by B. Rimoldi
* "A decomposition approach to CPM", IEEE Trans. Info Theory, March 1988
* See also my own notes at http://www.eecs.umich.edu/~anastas/docs/cpm.pdf
*/
fsm(int P, int M, int L);
/*!
* \brief Creates an FSMS describing the joint trellis of two FSMs.
*
* \param fsm1 first FSMS
* \param fsm2 second FSMS
*/
fsm(const fsm &FSM1, const fsm &FSM2);
/*!
* \brief Creates an FSMS representing n stages through the originial FSM (AKA radix-n FSM).
*
* \param original FSMS
* \param n Number of stages.
*/
fsm(const fsm &FSM, int n);
int I () const { return d_I; }
int S () const { return d_S; }
int O () const { return d_O; }
const std::vector<int> & NS () const { return d_NS; }
const std::vector<int> & OS () const { return d_OS; }
const std::vector< std::vector<int> > & PS () const { return d_PS; }
const std::vector< std::vector<int> > & PI () const { return d_PI; }
const std::vector<int> & TMi () const { return d_TMi; }
const std::vector<int> & TMl () const { return d_TMl; }
/*!
* \brief Creates an svg image of the trellis representation.
*
* \param filename filename
* \param number_stages ????
*
*/
void write_trellis_svg(std::string filename ,int number_stages);
/*!
* \brief Write the FSMS to a file.
*
* \param filename filename
*
*/
void write_fsm_txt(std::string filename);
};
#endif
|
