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
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
|
/*!
* \file
* \brief Convolutional encoder/decoder class test program
* \author Tony Ottosson and Adam Piatyszek
*
* -------------------------------------------------------------------------
*
* IT++ - C++ library of mathematical, signal processing, speech processing,
* and communications classes and functions
*
* Copyright (C) 1995-2008 (see AUTHORS file for a list of contributors)
*
* 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
* -------------------------------------------------------------------------
*/
#include <itpp/itcomm.h>
using namespace itpp;
using namespace std;
int main()
{
cout << "====================================" << endl;
cout << " Test of convolutional coders " << endl;
cout << "====================================" << endl;
Array<ivec> spectrum, spectrum_fast, spectrum_punct, spectrum_punct_fast;
spectrum.set_size(2);
spectrum_fast.set_size(2);
spectrum_punct.set_size(2);
spectrum_punct_fast.set_size(2);
Convolutional_Code code;
Punctured_Convolutional_Code code_punct;
BPSK bpsk;
BERC berc;
const int no_bits = 2500;
const int packet_size = 500;
int coded_packet_size;
bvec bits, tail_coded_bits, tail_decoded_bits, tailbite_coded_bits,
tailbite_decoded_bits, trunc_coded_bits, trunc_decoded_bits;
vec symbols;
ivec dist_profile;
ivec G(2);
G(0) = 0133;
G(1) = 0171;
int L = max(int2bits(G(0)), int2bits(G(1))); // L = 7
code.set_generator_polynomials(G, L);
code_punct.set_generator_polynomials(G, L);
bmat punct_matrix = "1 0 1; 1 1 0"; // results in R = 3/4
code_punct.set_puncture_matrix(punct_matrix);
cout << "------------------------------------------------------------------------------" << endl;
cout << "1) Rate 1/2 code" << endl;
cout << "------------------------------------------------------------------------------" << endl;
cout << "Catastrophic test = " << code.catastrophic() << endl;
cout << "Code rate = " << code.get_rate() << endl << endl;
code.calculate_spectrum(spectrum, 10, 10);
code.fast(spectrum_fast, 10, 10);
code.distance_profile(dist_profile, 10);
cout << "Spectrum:" << endl;
cout << "* Ad = " << spectrum(0) << endl;
cout << "* Cd = " << spectrum(1) << endl;
cout << "Spectrum, fast:" << endl;
cout << "* Ad = " << spectrum_fast(0) << endl;
cout << "* Cd = " << spectrum_fast(1) << endl << endl;
cout << "Distance profile = " << dist_profile << endl << endl;
cout << "Tail method test. Printing 30 bits starting from bit 1400:" << endl;
bits = randb(no_bits);
cout << "* Input bits = " << bits.mid(1400, 30) << endl;
tail_coded_bits = code.encode_tail(bits);
cout << "* Coded bits = " << tail_coded_bits.mid(1400, 30) << endl;
bpsk.modulate_bits(tail_coded_bits, symbols);
tail_decoded_bits = code.decode_tail(symbols);
cout << "* Decoded bits = " << tail_decoded_bits.mid(1400, 30) << endl;
berc.count(bits, tail_decoded_bits);
cout << "BER = " << berc.get_errorrate() << endl << endl;
cout << "Tailbite method test. Printing 30 bits starting from bit 1400:"
<< endl;
cout << "* Input bits = " << bits.mid(1400, 30) << endl;
tailbite_coded_bits = code.encode_tailbite(bits);
cout << "* Coded bits = " << tailbite_coded_bits.mid(1400, 30) << endl;
bpsk.modulate_bits(tailbite_coded_bits, symbols);
tailbite_decoded_bits = code.decode_tailbite(symbols);
cout << "* Decoded bits = " << tailbite_decoded_bits.mid(1400, 30) << endl;
berc.clear();
berc.count(bits, tailbite_decoded_bits);
cout << "BER = " << berc.get_errorrate() << endl << endl;
cout << "Trunc method test. Printing 30 bits starting from bit 1400:" << endl;
cout << "* Input bits = " << bits.mid(1400, 30) << endl;
trunc_coded_bits.set_size(0);
for (int i = 0; i < no_bits/packet_size; i++) {
trunc_coded_bits = concat(trunc_coded_bits,
code.encode_trunc(bits.mid(i*packet_size,
packet_size)));
}
cout << "* Coded bits = " << trunc_coded_bits.mid(1400, 30) << endl;
bpsk.modulate_bits(trunc_coded_bits, symbols);
trunc_decoded_bits.set_size(0);
coded_packet_size = round_i(packet_size / code.get_rate());
for (int i = 0; i < no_bits/packet_size; i++) {
trunc_decoded_bits =
concat(trunc_decoded_bits,
code.decode_trunc(symbols.mid(i*coded_packet_size,
coded_packet_size)));
}
cout << "* Decoded bits = " << trunc_decoded_bits.mid(1400, 30) << endl;
berc.clear();
berc.count(bits, trunc_decoded_bits);
cout << "BER = " << berc.get_errorrate() << endl << endl;
cout << "------------------------------------------------------------------------------" << endl;
cout << "1) Punctured code (R = 3/4)" << endl;
cout << "------------------------------------------------------------------------------" << endl;
cout << "Catastrophic test = " << code_punct.catastrophic() << endl;
cout << "Code rate = " << code_punct.get_rate() << endl;
cout << "Puncture matrix = " << code_punct.get_puncture_matrix() << endl
<< endl;
cout << "Tail method test. Printing 30 bits starting from bit 1400:" << endl;
bits = randb(no_bits);
cout << "* Input bits = " << bits.mid(1400, 30) << endl;
tail_coded_bits = code_punct.encode_tail(bits);
cout << "* Coded bits = " << tail_coded_bits.mid(1400, 30) << endl;
bpsk.modulate_bits(tail_coded_bits, symbols);
tail_decoded_bits = code_punct.decode_tail(symbols);
cout << "* Decoded bits = " << tail_decoded_bits.mid(1400, 30) << endl;
berc.count(bits, tail_decoded_bits);
cout << "BER = " << berc.get_errorrate() << endl << endl;
cout << "Tailbite method test. Printing 30 bits starting from bit 1400:"
<< endl;
cout << "* Input bits = " << bits.mid(1400, 30) << endl;
tailbite_coded_bits = code_punct.encode_tailbite(bits);
cout << "* Coded bits = " << tailbite_coded_bits.mid(1400, 30) << endl;
bpsk.modulate_bits(tailbite_coded_bits, symbols);
tailbite_decoded_bits = code_punct.decode_tailbite(symbols);
cout << "* Decoded bits = " << tailbite_decoded_bits.mid(1400, 30) << endl;
berc.clear();
berc.count(bits, tailbite_decoded_bits);
cout << "BER = " << berc.get_errorrate() << endl << endl;
cout << "Trunc method test. Printing 30 bits starting from bit 1400:" << endl;
cout << "* Input bits = " << bits.mid(1400, 30) << endl;
trunc_coded_bits.set_size(0);
for (int i = 0; i < no_bits/packet_size; i++) {
trunc_coded_bits = concat(trunc_coded_bits,
code_punct.encode_trunc(bits.mid(i*packet_size,
packet_size)));
}
cout << "* Coded bits = " << trunc_coded_bits.mid(1400, 30) << endl;
bpsk.modulate_bits(trunc_coded_bits, symbols);
trunc_decoded_bits.set_size(0);
coded_packet_size = round_i(packet_size / code_punct.get_rate());
for (int i = 0; i < no_bits/packet_size; i++) {
trunc_decoded_bits =
concat(trunc_decoded_bits,
code_punct.decode_trunc(symbols.mid(i*coded_packet_size,
coded_packet_size)));
}
cout << "* Decoded bits = " << trunc_decoded_bits.mid(1400, 30) << endl;
berc.clear();
berc.count(bits, trunc_decoded_bits);
cout << "BER = " << berc.get_errorrate() << endl << endl;
return 0;
}
|
