Method and apparatus for encoding and decoding data
View Patent ↗A method and apparatus for turbo encoding with a contention-free interleaver is provided herein. During operation an input block of size K′ is received. The original input block and the interleaved input block are encoded to obtain a codeword block, wherein the original input block is interleaved using an interleaver of size K′ and a permutation π(i)=(f 1 ×i+f 2 ×i 2 )mod K′, where 0≦i≦K′−1 is the sequential index of the symbol positions after interleaving, π(i) is the symbol index before interleaving corresponding to position i, K′ is the interleaver size in symbols, and f 1 and f 2 are the factors defining the interleaver. The values of K′, f 1 , f 2 are taken from at least one row of a table. The codeword block is transmitted through the channel.
1. A method for operating a turbo encoder, the method comprising the steps of:
receiving an input block of size K′; and
encoding the input block and an interleaved input block to obtain a codeword block, wherein the input block is interleaved using an interleaver of size K′ and a permutation π(i)=(f 1 ×i+f 2 ×i 2 )mod K′, where 0≦i≦K′−1 is a sequential index of symbol positions after interleaving, π(i) is a symbol index before interleaving corresponding to position i, K′ is an interleaver size in symbols, and f 1 and f 2 are factors defining the interleaver, and wherein the values of K′, f 1 , f 2 are taken from at least one row of the following table:
K′
f 1
f 2
112
41
84
144
17
108
160
21
120
184
57
46
208
27
52
232
85
58
264
17
198
304
37
76
336
115
84
344
193
86
360
133
90
376
45
94
392
243
98
400
151
40
408
155
102
424
51
106
440
91
110
448
29
168
464
247
58
480
89
180
488
91
122
496
157
62
656
185
82
672
43
252
736
139
92
768
217
48
816
127
102
848
239
106
880
137
110
896
215
112
944
147
118
976
59
122
992
65
124
1088
171
204
1120
67
140
1216
39
76
1280
199
240
1440
149
60
1664
183
104
1792
29
112
1856
57
116
1920
31
120
2016
113
420
2176
171
136
2368
367
444
2432
265
456
2496
181
468
2624
27
164
2688
127
504
2752
143
172
2880
29
300
3008
157
188
3200
111
240
3264
443
204
3392
51
212
3456
451
192
3520
257
220
3584
57
336
3648
313
228
3712
271
232
3840
331
120
3904
363
244
3968
375
248
4032
127
168
4224
43
264
4480
233
280
4608
337
480
4864
37
152
5376
251
336
5760
161
120
5888
323
184.
2. The method of claim 1 further comprising the step of:
transmitting the codeword block through a channel.
3. A method for operating a turbo encoder, the method comprising the steps of:
receiving an input block of size K′; and
encoding the input block and an interleaved input block to obtain a codeword block, wherein the input block is interleaved using an interleaver of size K′ and a permutation π(i)=(f 1 ×i+f 2 ×i 2 )mod K′, where 0≦i≦K′−1 is a sequential index of symbol positions after interleaving, π(i) is a symbol index before interleaving corresponding to position i, K′ is an interleaver size in symbols, and f 1 and f 2 are factors defining the interleaver, and wherein values of K′, f 1 , f 2 are taken from at least one row of the following table:
K′
f 1
f 2
1504
49
846
1696
55
954
1888
45
354
1952
59
610
4544
357
142
4736
71
444
4928
39
462
4992
127
234
5248
113
902
5824
89
182.
4. An apparatus for operating a turbo encoder, the apparatus comprising:
interleaver size determination circuitry that determines an interleaver size K′ from a set of sizes;
filler insertion circuitry receiving an input block of size K and padding the input block of size K into an input block of size K′;
an interleaver interleaving the input block of size K′, wherein the interleaver uses a permutation π(i)=(f 1 ×i+f 2 ×i 2 )mod K′, where 0≦i≦K′−1 is a sequential index of symbol positions after interleaving, π(i) is a symbol index before interleaving corresponding to position i, K′ is an interleaver size in symbols, and f 1 and f 2 are factors defining the interleaver, and wherein values of K′, f 1 , f 2 are taken from at least one row of the following table:
K′
f 1
f 2
112
41
84
144
17
108
160
21
120
184
57
46
208
27
52
232
85
58
264
17
198
304
37
76
336
115
84
344
193
86
360
133
90
376
45
94
392
243
98
400
151
40
408
155
102
424
51
106
440
91
110
448
29
168
464
247
58
480
89
180
488
91
122
496
157
62
656
185
82
672
43
252
736
139
92
768
217
48
816
127
102
848
239
106
880
137
110
896
215
112
944
147
118
976
59
122
992
65
124
1088
171
204
1120
67
140
1216
39
76
1280
199
240
1440
149
60
1664
183
104
1792
29
112
1856
57
116
1920
31
120
2016
113
420
2176
171
136
2368
367
444
2432
265
456
2496
181
468
2624
27
164
2688
127
504
2752
143
172
2880
29
300
3008
157
188
3200
111
240
3264
443
204
3392
51
212
3456
451
192
3520
257
220
3584
57
336
3648
313
228
3712
271
232
3840
331
120
3904
363
244
3968
375
248
4032
127
168
4224
43
264
4480
233
280
4608
337
480
4864
37
152
5376
251
336
5760
161
120
5888
323
184.
5. The apparatus of claim 4 further comprising:
an encoder that encodes the input block and the interleaved input block to obtain a codeword block.
6. The apparatus of claim 4 where interleaver size K′ is determined from a set of sizes comprises using K′=α p ×f, p min ≦p≦p max ; f min ≦f≦f max , wherein α is an integer, f is a continuous integer between f min and f max , and p takes integer values between p min and p max , a>1, p max >p min , p min >1.
7. The apparatus of claim 6 wherein α=2, p min =3, p max =6, f min =33, f max =64.
8. The apparatus of claim 6 where an inverse of the interleaver is quadratic.
9. An apparatus for operating a turbo encoder, the apparatus comprising:
interleaver size determination circuitry that determines an interleaver size K′ from a set of sizes;
filler insertion circuitry receiving an input block of size K and padding the input block of size K into an input block of size K′;
an interleaver interleaving the input block of size K′, wherein interleaver uses a permutation π(i)=(f 1 ×i+f 2 ×i 2 )mod K′, where 0≦i≦K′−1 is a sequential index of symbol positions after interleaving, π(i) comprises a symbol index before interleaving corresponding to position i, K′ is an interleaver size in symbols, and f 1 and f 2 are factors defining the interleaver, and wherein values of K′, f 1 , f 2 are taken from at least one row of the following table:
K′
f 1
f 2
1504
49
846
1696
55
954
1888
45
354
1952
59
610
4544
357
142
4736
71
444
4928
39
462
4992
127
234
5248
113
902
5824
89
182.
10. The apparatus of claim 9 further comprising:
an encoder that encodes the input block and the interleaved input block to obtain a codeword block.
11. The apparatus of claim 9 wherein an inverse of the interleaver is degree 3 or 4.