# Patent

## Title
Method for determining transport block size and signal transmission method using the same

## Abstract

A method for performing, by a first device, channel coding of data to be transmitted to a second device, the method includes: determining a size of a transport block for the data; attaching a first cyclic redundancy check (CRC) code to the transport block having the determined size to produce a first CRC-attached transport block; and segmenting the first CRC-attached transport block into multiple code blocks, wherein the size of the transport block is determined from among a plurality of predetermined transport block sizes such that the multiple code blocks have a same size as each other.

## Background
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a Continuation of U.S. application Ser. No. 13/584,600, filed Aug. 13, 2012, which claims priority to U.S. application Ser. No. 12/332,165, filed on Dec. 10, 2008, now U.S. Pat. No. 8,266,513, which claims priority to Korean Patent Application 10-2008-0097705, filed on Oct. 6, 2008, U.S. Provisional Application 61/024,914, filed on Jan. 31, 2008 and U.S. Provisional Application 61/026,143, filed on Feb. 5, 2008. The entire contents of all these applications are hereby incorporated by reference as fully set forth herein in their entirety.


BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method and device for effectively determining the size of a data block or a transport block in a wireless communication system, and a method for transmitting signals using the same method.
2. Discussion of the Related Art
Generally, in a communication system, a transmission end of the communication system encodes transmission information using a forward error correction code, and transmits the encoded information to a reception end of the communication system, such that errors caused by a channel can be corrected in the information received in the reception end. The reception end demodulates a reception signal, decodes a forward error correction code, and recovers the transmission information transferred from the transmission end. During this decoding process, reception signal errors caused by a channel can be corrected.
There are various kinds of forward error correction codes that may be used. For the convenience of description, a turbo code will hereinafter be described as an example of the forward error correction code. The turbo code includes a recursive systematic convolution encoder and an interleaver. In case of actually implementing the turbo code, the interleaver facilitates parallel decoding, and an example of this interleaver may be a quadratic polynomial permutation (QPP) interleaver. It is well known in the art that this QPP interleaver maintains a superior throughput or performance in only a specific-sized data block. In this case, the term “data block” is block unit data encoded by the encoder. If we think block unit data transferred from an upper layer to a physical layer is encoded without segmentation discussed below, this data block may also be called as a transport block (TB). On the other hand, if we think the segmentation of the transport block to be encoded, this data block may be matched to “a code block”.
In general, the larger the data-block size, the higher the turbo-code performance. A data block of more than a specific size is segmented into a plurality of small-sized data blocks by an actual communication system, such that the small-sized data blocks are encoded for the convenience of actual implementation. The divided small-sized data blocks are called code blocks. Generally, although these code blocks have the same size, one of several code blocks may have another size due to the limitation of the QPP interleaver size. A forward error correction coding process on the basis of a code block of a predetermined interleaver size is performed on the small-sized data blocks, and the resultant data blocks are then transferred to an RF (Radio Frequency) channel. In this case, a burst error may occur in the above process of transferring the resultant data blocks to the RF channel, such that the above resultant data blocks are interleaved to reduce an influence of the burst error. The interleaved data blocks are mapped to actual radio resources, such that the mapped result is transferred.
An amount of radio resources used in an actual transmission process is constant, such that a rate matching process should be performed on the encoded code blocks due to the constant amount of radio resources. Generally, the rate matching process is implemented by a puncturing or a repetition. For example, the rate matching may also be performed on the basis of an encoded code block in the same manner as in a WCDMA of the 3GPP. For another example, a systematic part and a parity part of the encoded code block may be separated from each other. The rate matching process may be performed on the systematic part and the parity part together. On the other hand, the rate matching process may also be independently performed on each of the systematic part and the parity part.
FIG. 1 is a conceptual diagram illustrating basic operations of a turbo encoder.
As shown in FIG. 1, if a turbo-encoder receives one code block, it divides the received one code block into a systematic part (S) and parity parts (P1 and P2). The systematic part S and the parity parts P1 and P2 pass through individual sub-block interleavers, respectively. Thus, the systematic part S and the parity parts P1 and P2 may be interleaved by different sub-block interleavers, and the interleaved result is stored in a circular buffer.
As can be seen from FIG. 1, the systematic part and the parity parts of the code block may be separated from each other, and the rate matching process is performed on the individual separated parts, but the example of FIG. 1 has been disclosed for only illustrative purposes and the scope and spirit of the present invention are not limited to this example and can also be applied to other examples. For the convenience of description, it is assumed that a code rate is a value of 1⁄3.
Although a variety of transport block sizes may be defined according to service categories of an upper layer, it is preferable that the transport block sizes may be quantized to effectively perform the signaling of various transport block sizes. During the quantization process, in order to adjust a source data block transferred from an upper layer to the size of a data block of a physical layer, a dummy bit is added to the source data block. During this quantization process, it is preferable to minimize the amount of added dummy bits.
SUMMARY OF THE INVENTION
To achieve these objects and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, a signal transmission method and device is presented, the method comprising: determining the number of code blocks to be used for transmitting a transport block with a specific size, and mapping the transport block to the code blocks corresponding to the determined number; attaching a cyclic redundancy check (CRC) to each of the code blocks; encoding each of the CRC-attached code blocks by a turbo-encoder including an internal interleaver; and transmitting the encoded code blocks, wherein the specific size of the transport block corresponds to any transport block size in predetermined transport block size combinations, and wherein any transport block size in the predetermined transport block size combinations is predetermined such that the sum of a length of any one code block from among the code blocks mapped to the transport block with the specific length and a length of the CRC attached to the one code block is equal to a block size of the internal interleaver.
The block size of the internal interleaver of the turbo-encoder may be predetermined as a combination of predetermined bit lengths.
Under the above-mentioned assumption, if the number of code blocks to be used for transmitting the transport block is 1, the specific transport block size may be any one of the predetermined transport block size combinations in which any one of the predetermined transport block size corresponds to the sum of a CRC length and the predetermined internal interleaver's block sizes.
Under the same assumption, if the number of code blocks to be used for transmitting the transport block is at least 2, the transport block is segmented into at least two code blocks having the same length, and is mapped to the at least two code blocks.
The above-mentioned operations may be generalized as the following expression.
If the specific size of the transport block is N, the number of the code blocks to be used for transmitting the transport block is M, the length of each of the M code blocks is Nc, and the length of the CRC is L, the specific transport block size N may satisfy an equation denoted by N=M*NC−L, and the specific transport block size may correspond to any one of the predetermined transport block size combinations in which a value of Nc+L corresponds to the internal interleaver's block sizes predetermined as a combination of predetermined bit lengths.
In more detail, the block size of the internal interleaver of the turbo-encoder may predetermined as ‘K’ value according to an index (i) in a following Table 1:














TABLE 1





i
K
i
K
i
K
i
K






















1
40
48
416
95
1120
142
3200


2
48
49 
424
96
1152
143
3264


3
56
50 
432
97
1184
144
3328


4
64
51 
440
98
1216
145
3392


5
72
52 
448
99
1248
146
3456


6
80
53 
456
100
1280
147
3520


7
88
54 
464
101 
1312
148
3584


8
96
55 
472
102 
1344
149
3648


9
104
56
480
103 
1376
150
3712


10
112
57
488
104 
1408
151
3776


11 
120
58
496
105
1440
152
3840


12 
128
59
504
106
1472
153
3904


13 
136
60
512
107
1504
154
3968


14 
144
61
528
108
1536
155
4032


15 
152
62
544
109
1568
156
4096


16 
160
63
560
110
1600
157
4160


17 
168
64
576
111
1632
158
4224


18 
176
65
592
112
1664
159
4288


19 
184
66
608
113
1696
160
4352


20 
192
67
624
114
1728
161
4416


21 
200
68
640
115
1760
162
4480


22 
208
69
656
116
1792
163
4544


23 
216
70
672
117
1824
164
4608


24 
224
71
688
118
1856
165
4672


25 
232
72
704
119
1888
166
4736


26 
240
73
720
120
1920
167
4800


27 
248
74
736
121
1952
168
4864


28 
256
75
752
122
1984
169
4928


29 
264
76
768
123
2016
170
4992


30 
272
77
784
124
2048
171
5056


31 
280
78
800
125
2112
172
5120


32 
288
79
816
126
2176
173
5184


33 
296
80
832
127
2240
174
5248


34 
304
81
848
128
2304
175
5312


35 
312
82
864
129
2368
176
5376


36 
320
83
880
130
2432
177
5440


37 
328
84
896
131
2496
178
5504


38 
336
85
912
132
2560
179
5568


39 
344
86
928
133
2624
180
5632


40 
352
87
944
134
2688
181
5696


41
360
88
960
135
2752
182
5760


42 
368
89
976
136
2816
183
5824


43 
376
90
992
137
2880
184
5888


44 
384
91
1008
138
2944
185
5952


45 
392
92
1024
139
3008
186
6016


46 
400
93
1056
140
3072
187
6080


47 
408
94
1088
141
3136
188
6144









Under the above-mentioned assumption, if the number of code blocks to be used for transmitting the transport block is 1, the specific transport block size may be any one of the transport block size combinations in which any transport block size corresponds to the sum of a K value shown in Table 1 and a CRC length.
The above-mentioned operations may be generalized as the following expression.
If the specific size of the transport block is N, the number of the code blocks to be used for transmitting the transport block is M, the length of each of the M code blocks is Nc, and the length of the CRC is L, the specific transport block size N may satisfy an equation denoted by N=M*NC−L, and the specific transport block size may correspond to any one of transport block size combinations in which a value of Nc+L corresponds to the K value shown in the above table 1.
The specific size N of the transport block may be set to a length selected from among combinations shown in a following table 2 according to the number M of the code blocks to be used for transmitting the transport block.




















TABLE 2





M
N
M
N
M
N
M
N
M
N
M
N
M
N




























2
6200
2
11448
4 
19080
5 
30576
8
48424
13
74544
19 
112608


2
6328
2
11576
4 
19336
6 
30936
8
48936
13
75376
19 
113824


2
6456
2
11704
4
19592
6 
31320
9
49296
13
76208
19
115040


2
6584
2
11832
4
19848
6
31704
9
49872
13
77040
19
116256


2
6712
2
11960
4
20104
6 
32088
9
50448
13 
77872
20
117256


2
6840
2
12088
4
20360
6
32472
9
51024
13
78704
20
118536


2
6968
2
12216
4
20616
6
32856
9
51600
13
79536
20
119816


2
7096
3
12384
4
20872
6
33240
9
52176
14
80280
20
121096


2
7224
3
12576
4
21128
6
33624
9
52752
14
81176
20
122376


2
7352
3
12768
4
21384
6
34008
9
53328
14
82072
21
123120


2
7480
3
12960
4
21640
6
34392
9
53904
14
82968
21
124464


2
7608
3
13152
4 
21896
6
34776
9
54480
14
83864
21
125808


2
7736
3
13344
4
22152
6 
35160
9
55056
14
84760
21
127152


2
7864
3
13536
4
22408
6
35544
10
55416
14
85656
21
128496


2
7992
3
13728
4
22664
6
35928
10
56056
15
86016
22
130392


2
8120
3
13920
4
22920
6
36312
10
56696
15
86976
22
131800


2
8248
3
14112
4
23176
6
36696
10
57336
15
87936
22
133208


2
8376
3
14304
4
23432
7
36992
10
57976
15
88896
22
134616


2
8504
3
14496
4
23688
7
37440
10
58616
15
89856
23
134848


2
8632
3
14688
4
23944
7
37888
10
59256
15
90816
23
136320


2
8760
3
14880
4
24200
7
38336
10
59896
15
91776
23
137792


2
8888
3
15072
4
24456
7
38784
10
60536
16
92776
23
139264


2
9016
3
15264
5
24496
7
39232
10
61176
16
93800
23
140736


2
9144
3
15456
5
24816
7
39680
11
61664
16
94824
24
142248


2
9272
3
15648
5
25136
7
40128
11
62368
16
95848
24
143784


2
9400
3
15840
5
25456
7
40576
11
63072
16
96872
24
145320


2
9528
3
16032
5
25776
7
41024
11
63776
16
97896
24
146856


2
9656
3
16224
5
26096
7
41472
11
64480
17
98576
25
148176


2
9784
3
16416
5
26416
7
41920
11
65184
17
99664
25
149776


2
9912
3
16608
5
26736
7
42368
11
65888
17
100752
25
151376


2
10040
3
16800
5
27056
7
42816
11
66592
17
101840
25
152976


2
10168
3
16992
5
27376
8
43304
11
67296
17
102928




2
10296
3
17184
5
27696
8
43816
12
68040
17
104016




2
10424
3
17376
5
28016
8
44328
12
68808
18
104376




2
10552
3
17568
5
28336
8
44840
12
69576
18
105528




2
10680
3
17760
5
28656
8
45352
12
70344
18
106680




2
10808
3
17952
5
28976
8
45864
12
71112
18
107832




2
10936
3
18144
5
29296
8
46376
12
71880
18
108984




2
11064
3
18336
5
29616
8
46888
12
72648
18
110136




2
11192
4
18568
5
29936
8
47400
12
73416
19
110176




2
11320
4
18824
5
30256
8
47912
13
73712
19
111392









The method may further comprise: transmitting information indicating a Modulation and Coding Scheme (MCS) and an available resource area size to a reception end; wherein the MCS and that available resource size represent the specific transport block size.
And, if the transport block size value based on the MCS and the available resource size is not contained in the predetermined transport block size combinations, a maximum transport block size in the predetermined transport block size combinations, which is equal to or smaller than the transport block size value based on the MCS and the available resource size; a minimum transport block size in the predetermined transport block size combinations, which is larger than the transport block size value based on the MCS and the available resource size; or a specific transport block size in the predetermined transport block size combinations, which has a minimum difference with the transport block size value based on the MCS and the available resource size, may be used as the specific transport block size.
In another aspect of the present invention, there is provided a signal transmission method comprising: attaching a first cyclic redundancy check (CRC) having a length of L to a transport block having a length of N; segmenting the transport block to which the first CRC is attached into M number of code blocks, each of which has a length of Nc; attaching a second cyclic redundancy check (CRC) having a length of L to each of the M code blocks; encoding, by a turbo-encoder comprising an internal interleaver, the M code blocks, each of which has the second CRC; and transmitting the encoded M code blocks, wherein the transport block size N satisfies an equation denoted by N=M*NC−L (where N, Nc, M, and L are natural numbers), where a value of Nc+L has any one of block sizes of the internal interleaver of the turbo-encoder.
In another aspect of the present invention, there is provided a signal transmission method comprising: mapping a transport block having a length of N to at least one code block; encoding the at least one code block by a turbo-encoder comprising an internal interleaver; and transmitting the encoded code block, wherein the transport block size N is selected from a transport block size combination comprising all or some of values shown in a following table 3.
















TABLE 3







16
392 
1096
3176
6200
12216
22152
37440
62368
101840


24 
400 
1128
3240
6328 
12384
22408
37888
63072
102928


32 
408 
1160
3304
6456 
12576
22664
38336
63776
104016


40 
416 
1192
3368
6584 
12768
22920
38784
64480
104376


48 
424 
1224
3432
6712 
12960
23176
39232
65184
105528


56 
432 
1256
3496
6840 
13152
23432
39680
65888
106680


64 
440 
1288
3560
6968 
13344
23688
40128
66592
107832


72 
448 
1320
3624
7096 
13536
23944
40576
67296
108984


80 
456 
1352
3688
7224 
13728
24200
41024
68040
110136


88 
464 
1384
3752
7352 
13920
24456
41472
68808
110176


96 
472 
1416
3816
7480 
14112
24496
41920
69576
111392


104
480 
1448
3880
7608
14304
24816
42368
70344
112608


112
488 
1480
3944
7736 
14496
25136
42816
71112
113824


120
504 
1512
4008
7864 
14688
25456
43304
71880
115040


128
520 
1544
4072
7992 
14880
25776
43816
72648
116256


136
536 
1576
4136
8120 
15072
26096
44328
73416
117256


144
552 
1608
4200
8248 
15264
26416
44840
73712
118536


152
568 
1640
4264
8376 
15456
26736
45352
74544
119816


160
584 
1672
4328
8504 
15648
27056
45864
75376
121096


168
600 
1704
4392
8632 
15840
27376
46376
76208
122376


176
616 
1736
4456
8760 
16032
27696
46888
77040
123120


184
632 
1768
4520
8888 
16224
28016
47400
77872
124464


192
648 
1800
4584
9016 
16416
28336
47912
78704
125808


200
664 
1832
4648
9144 
16608
28656
48424
79536
127152


208
680 
1864
4712
9272 
16800
28976
48936
80280
128496


216
696 
1896
4776
9400 
16992
29296
49296
81176
130392


224
712 
1928
4840
9528 
17184
29616
49872
82072
131800


232
728 
1960
4904
9656 
17376
29936
50448
82968
133208


240
744 
1992
4968
9784 
17568
30256
51024
83864
134616


248
760 
2024
5032
9912 
17760
30576
51600
84760
134848


256
776 
2088
5096
10040
17952
30936
52176
85656
136320


264
792 
2152
5160
10168
18144
31320
52752
86016
137792


272
808
2216
5224
10296
18336
31704
53328
86976 
139264


280
824
2280
5288
10424
18568
32088
53904
87936 
140736


288
840
2344
5352
10552
18824
32472
54480
88896 
142248


296
856
2408
5416
10680
19080
32856
55056
89856 
143784


304
872
2472
5480
10808
19336
33240
55416
90816 
145320


312
888
2536
5544
10936
19592
33624
56056
91776 
146856


320
904
2600
5608
11064
19848
34008
56696
92776 
148176


328
920
2664
5672
11192
20104
34392
57336
93800 
149776


336
936
2728
5736
11320
20360
34776
57976
94824 
151376


344
952
2792
5800
11448
20616
35160
58616
95848 
152976


352
968
2856
5864
11576
20872
35544
59256
96872



360
984
2920
5928
11704
21128
35928
59896
97896



368
1000 
2984
5992
11832
21384
36312
60536
98576



376
1032 
3048
6056
11960
21640
36696
61176
99664



384
1064 
3112
6120
12088
21896
36992
61664
100752









According to the above-mentioned embodiments of the present invention, if a transport block received from an upper layer is segmented into a plurality of code blocks, and the code blocks are encoded by a turbo-encoder, the present invention is able to avoid addition of dummy bits due to the length of an input bit of an internal interleaver of the turbo-encoder, such that it can effectively transmit signals.



BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are included to provide a further understanding of the invention, illustrate embodiments of the invention and together with the description serve to explain the principle of the invention.
In the drawings:
FIG. 1 is a conceptual diagram illustrating basic operations of a turbo-encoder according to the present invention;
FIGS. 2A, 2B and 3 are conceptual diagrams illustrating a method for dividing a long transport block into a plurality of short transport blocks in a 3GPP system, and attaching a CRC to the short transport blocks according to the present invention;
FIG. 4 is a conceptual diagram illustrating a principle of establishing the transport block size according to one embodiment of the present invention; and
FIG. 5 shows an example of a resource structure according to the present invention.
FIG. 6 shows a flow chart according to the present invention.



DETAILED DESCRIPTION OF THE INVENTION
Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. Prior to describing the present invention, it should be noted that most terms disclosed in the present invention correspond to general terms well known in the art, but some terms have been selected by the applicant as necessary and will hereinafter be disclosed in the following description of the present invention. Therefore, it is preferable that the terms defined by the applicant be understood on the basis of their meanings in the present invention.
For the convenience of description and better understanding of the present invention, the following detailed description will disclose a variety of embodiments and modifications of the present invention. In some cases, in order to prevent ambiguous concepts of the present invention from occurring, conventional devices or apparatus well known to those skilled in the art will be omitted and be denoted in the form of a block diagram on the basis of the important functions of the present invention. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.
As described above, it is well known to those skilled in the art that the internal interleaver of the turbo code has a superior performance in only a specific-sized data block. If the data block size is larger than a predetermined size, a transport block or a data block is segmented into a plurality of code blocks, and this process is called segmentation. Due to the limitation of the interleaver size, the transport or data block may not be segmented into the same-sized code blocks.
However, in the case of a downlink, a channel quality indicator must be applied to all code blocks segmented from the data block, such that it is preferable that the transport or data block be segmented into the same-sized code blocks. If the data block size or the segmented code block size is different from the internal interleaver size of the turbo code, a dummy bit is inserted such that transmission efficiency is reduced. In order to solve this problem, it is preferable that the segmentation process be performed not to require this dummy bit.
For the above-mentioned operations, there is needed a consideration of the block size of the internal encoder of the turbo-encoder caused by the inserted dummy bit. In order to perform the channel coding, a CRC is attached to a transport block or code blocks segmented from the transport block, and at the same time the length of each data block is changed to another length, such that a consideration of the channel coding is needed.
Firstly, the above-mentioned CRC attachment process will hereinafter be described in detail.
The CRC for detecting errors is attached to the transport block received from an upper layer. For the convenience of implementation, and it can also be attached to each of the segmented code blocks.
FIGS. 2A, 2B and 3 are conceptual diagrams illustrating a method for dividing a long transport block into a plurality of short length code blocks in a 3GPP system, and attaching a CRC to the short code blocks according to the present invention.
The 3GPP system segments a long transport block (TB) into a plurality of short code blocks, encodes the short code blocks, collects the encoded short code blocks, and transmits the collected short code blocks. Detailed descriptions of the above operations of the 3GPP system will hereinafter be described with reference to FIGS. 2A, 2B and 3.
Referring to FIGS. 2A, 2B and 3, the long transport block is CRC-attached, that is, a CRC is attached to the transport block at step S101. Thereafter, the CRC-attached long transport block is segmented into a plurality of short code blocks at step S102. Similar to this, as shown in reference numbers S201 ̃S203 of FIGS. 2B and 3, the CRC is attached to the long transport block, and the CRC-attached transport block is segmented into a plurality of code blocks. However, if the length of the transport block received from the upper layer is equal to or shorter than a predetermined length capable of being constructed by one code block, i.e., a maximum length of the internal interleaver of the turbo-encoder, the segmentation of the transport block may be omitted. In this case, the process for attaching a CB CRC may also be omitted.
In the meantime, each of short code blocks is CRC-attached, that is, the CRC attachment process is then performed on each of the code blocks at step S103. In more detail, as shown in the reference number S204 of FIGS. 2B and 3, each of the code blocks includes a CRC.
Also, the code blocks, each of which includes the CRC, are applied to a channel encoder, such that the channel coding process is performed on the resultant code blocks at step S104. Thereafter, the rate matching process S105, and the code block concatenation and channel interleaving process S106 are sequentially applied to the individual code blocks, such that the resultant code blocks are transmitted to a reception end.
Therefore, according to the following embodiment, there is proposed a process for determining the size of a transport block in consideration of the two-stage CRC attachment process. In the case where the size of a transport block is less than a predetermined size (such as, maximum internal interleaver size) and this transport block is mapped to one code block, the embodiment of the present invention provides a method for establishing the transport block size in consideration of only one CRC.
Under the above-mentioned assumption, a method for mapping the transport block to one code block will hereinafter be described. In order to remove the necessity of the conventional art of attaching the dummy bit on the condition that the transport block is mapped to one codeword, this embodiment of the present invention allows the sum of the transport block size (N) and one CRC length to be equal to an block size of the internal interleaver of the turbo-interleaver. The following Table 1 represents a combination of block sizes of the internal interleaver of the turbo-encoder.














TABLE 1





i
K
i
K
i
K
i
K






















1
40
48
416
95
1120
142
3200


2
48
49 
424
96
1152
143
3264


3
56
50 
432
97
1184
144
3328


4
64
51 
440
98
1216
145
3392


5
72
52 
448
99
1248
146
3456


6
80
53 
456
100
1280
147
3520


7
88
54 
464
101 
1312
148
3584


8
96
55 
472
102 
1344
149
3648


9
104
56
480
103 
1376
150
3712


10
112
57
488
104 
1408
151
3776


11 
120
58
496
105
1440
152
3840


12 
128
59
504
106
1472
153
3904


13 
136
60
512
107
1504
154
3968


14 
144
61
528
108
1536
155
4032


15 
152
62
544
109
1568
156
4096


16 
160
63
560
110
1600
157
4160


17 
168
64
576
111
1632
158
4224


18 
176
65
592
112
1664
159
4288


19 
184
66
608
113
1696
160
4352


20 
192
67
624
114
1728
161
4416


21 
200
68
640
115
1760
162
4480


22 
208
69
656
116
1792
163
4544


23 
216
70
672
117
1824
164
4608


24 
224
71
688
118
1856
165
4672


25 
232
72
704
119
1888
166
4736


26 
240
73
720
120
1920
167
4800


27 
248
74
736
121
1952
168
4864


28 
256
75
752
122
1984
169
4928


29 
264
76
768
123
2016
170
4992


30 
272
77
784
124
2048
171
5056


31 
280
78
800
125
2112
172
5120


32 
288
79
816
126
2176
173
5184


33 
296
80
832
127
2240
174
5248


34 
304
81
848
128
2304
175
5312


35 
312
82
864
129
2368
176
5376


36 
320
83
880
130
2432
177
5440


37 
328
84
896
131
2496
178
5504


38 
336
85
912
132
2560
179
5568


39 
344
86
928
133
2624
180
5632


40 
352
87
944
134
2688
181
5696


41
360
88
960
135
2752
182
5760


42 
368
89
976
136
2816
183
5824


43 
376
90
992
137
2880
184
5888


44 
384
91
1008
138
2944
185
5952


45 
392
92
1024
139
3008
186
6016


46 
400
93
1056
140
3072
187
6080


47 
408
94
1088
141
3136
188
6144









Therefore, as shown in Table 1, if the transport block is mapped to one code block, it is preferable that the transport block has a specific length acquired when the length of a CRC attached to the transport block is subtracted from an block size (K) of the internal interleaver. Provided that the length of a CRC attached to the transport block is 24 bits, the transport block size (N) acquired when the transport block is mapped to one code block may be a K−24. That is, the transport block size according to this embodiment may be selected from combinations of the following Table 4.














TABLE 4





i
N
i
N
i
N
i
N






















1
16
48
392
95
1096
142
3176


2
24
49
400 
96
1128
143
3240


3
32
50
408
97
1160
144
3304


4
40
51
416
98
1192
145
3368


5
48
52
424
99
1224
146
3432


6
56
53
432
100
1256
147
3496


7
64
54
440
101
1288
148
3560


8
72
55
448
102
1320
149 
3624


9
80
56
456 
103
1352
150 
3688


10
88
57
464
104
1384
151
3752


11
96
58
472 
105
1416
152 
3816


12
104
59
480 
106
1448
153
3880


13
112 
60
488 
107
1480
154 
3944


14
120 
61
504 
108
1512
155 
4008


15
128 
62
520 
109
1544
156 
4072


16
136 
63
536 
110
1576
157 
4136


17
144 
64
552 
111
1608
158 
4200


18
152 
65
568 
112
1640
159 
4264


19
160 
66
584 
113
1672
160 
4328


20
168 
67
600 
114
1704
161 
4392


21
176 
68
616 
115
1736
162 
4456


22
184 
69
632 
116
1768
163 
4520


23
192 
70
648 
117
1800
164 
4584


24
200 
71
664 
118
1832
165 
4648


25
208 
72
680 
119 
1864
166
4712


26
216 
73
696 
120 
1896
167 
4776


27
224 
74
712 
121 
1928
168 
4840


28
232 
75
728 
122 
1960
169 
4904


29
240 
76
744 
123 
1992
170 
4968


30
248 
77
760 
124 
2024
171 
5032


31
256 
78
776 
125 
2088
172 
5096


32
264 
79
792 
126 
2152
173 
5160


33
272 
80
808 
127 
2216
174 
5224


34
280 
81
824 
128 
2280
175 
5288


35
288
82
840 
129 
2344
176 
5352


36
296 
83
856 
130 
2408
177 
5416


37
304 
84
872 
131 
2472
178 
5480


38
312 
85
888 
132 
2536
179 
5544


39
320 
86
904 
133 
2600
180
5608


40
328 
87
920 
134 
2664
181 
5672


41
336 
88
936 
135 
2728
182 
5736


42
344 
89
952 
136 
2792
183 
5800


43
352 
90
968 
137 
2856
184 
5864


44
360 
91
984 
138 
2920
185 
5928


45
368 
92
1000
139
2984
186 
5992


46
376 
93
1032
140 
3048
187 
6056


47
384 
94
1064
141 
3112
188 
6120









In the meantime, a method for segmenting one transport block into two or more code blocks and performing a mapping process on the segmented code blocks will hereinafter be described in detail.
If one transport block is segmented into two or more code blocks, a CRC for the transport block is attached to the transport block as shown in FIGS. 2 and 3, and a CRC for each code block is attached to each of the segmented code blocks. Under this assumption, in order to avoid the conventional practice of adding of dummy bits, it is preferable that the sum of the size of a any one segmented code block and the size of a CRC attached to a corresponding code block is equal to an input bit size of the internal interleaver, as shown in Table 1.
Also, this embodiment of the present invention allows each of the segmented codewords to have the same size. Different-sized code blocks created by the segmentation of the transport block are caused by the limitation of the size of the internal interleaver of the turbo-encoder. If the transport block size is pre-established in consideration of the size of the internal interleaver of the turbo-encoder as described in this embodiment, there is no need for the individual code blocks to have different sizes.
Under the above-mentioned assumption, a method for establishing the size of the transport block according to this embodiment will hereinafter be described in detail.
FIG. 4 is a conceptual diagram illustrating a principle of establishing the transport block size according to one embodiment of the present invention.
Firstly, it is assumed that an L-sized CRC is attached to an N-sized transport block (TB). If the CRC-attached transport block (TB) size is longer than the maximum length of the internal interleaver, the transport block is segmented into a plurality of code blocks (CBs). As can be seen from FIG. 4, the transport block (TB) size is segmented into M (CB1 ̃CBM), each of which has the same length of Nc bits.
In the meantime, the L-sized CRC is attached to each of the M code blocks.
In this way, provided that each of the segmented code blocks has the same length and the lengths of two attached CRCs are considered, the transport block size N can be represented by the following equation 1:

N+L*M+L=M*(Nc+L)=>N=M*Nc−L  [Equation 1]

If the CRC of 24 bits is used, the above Equation 1 may be represented by another equation of N=M*Nc−24.
Each of the segmented code blocks includes the CRC, such that the CRC-attached code blocks are applied to the internal interleaver of the turbo-encoder. Therefore, as shown in FIG. 4, the length of the CRC-attached code blocks is equal to the internal interleaver's block size (K) shown in Table 1, as represented by the following equation 2:

Nc+L=K  [Equation 2]

Based on the above-mentioned description, this embodiment provides a method for using the following transport block sizes shown in the following Table 2. The following Table 2 shows a variety of cases illustrating a relationship between a single transport block and a maximum of 25 code blocks mapped to this single transport block.




















TABLE 2





M
N
M
N
M
N
M
N
M
N
M
N
M
N




























2
6200
2
11448
4 
19080
5 
30576
8
48424
13
74544
19 
112608


2
6328
2
11576
4 
19336
6 
30936
8
48936
13
75376
19 
113824


2
6456
2
11704
4
19592
6 
31320
9
49296
13
76208
19
115040


2
6584
2
11832
4
19848
6
31704
9
49872
13
77040
19
116256


2
6712
2
11960
4
20104
6 
32088
9
50448
13 
77872
20
117256


2
6840
2
12088
4
20360
6
32472
9
51024
13
78704
20
118536


2
6968
2
12216
4
20616
6
32856
9
51600
13
79536
20
119816


2
7096
3
12384
4
20872
6
33240
9
52176
14
80280
20
121096


2
7224
3
12576
4
21128
6
33624
9
52752
14
81176
20
122376


2
7352
3
12768
4
21384
6
34008
9
53328
14
82072
21
123120


2
7480
3
12960
4
21640
6
34392
9
53904
14
82968
21
124464


2
7608
3
13152
4 
21896
6
34776
9
54480
14
83864
21
125808


2
7736
3
13344
4
22152
6 
35160
9
55056
14
84760
21
127152


2
7864
3
13536
4
22408
6
35544
10
55416
14
85656
21
128496


2
7992
3
13728
4
22664
6
35928
10
56056
15
86016
22
130392


2
8120
3
13920
4
22920
6
36312
10
56696
15
86976
22
131800


2
8248
3
14112
4
23176
6
36696
10
57336
15
87936
22
133208


2
8376
3
14304
4
23432
7
36992
10
57976
15
88896
22
134616


2
8504
3
14496
4
23688
7
37440
10
58616
15
89856
23
134848


2
8632
3
14688
4
23944
7
37888
10
59256
15
90816
23
136320


2
8760
3
14880
4
24200
7
38336
10
59896
15
91776
23
137792


2
8888
3
15072
4
24456
7
38784
10
60536
16
92776
23
139264


2
9016
3
15264
5
24496
7
39232
10
61176
16
93800
23
140736


2
9144
3
15456
5
24816
7
39680
11
61664
16
94824
24
142248


2
9272
3
15648
5
25136
7
40128
11
62368
16
95848
24
143784


2
9400
3
15840
5
25456
7
40576
11
63072
16
96872
24
145320


2
9528
3
16032
5
25776
7
41024
11
63776
16
97896
24
146856


2
9656
3
16224
5
26096
7
41472
11
64480
17
98576
25
148176


2
9784
3
16416
5
26416
7
41920
11
65184
17
99664
25
149776


2
9912
3
16608
5
26736
7
42368
11
65888
17
100752
25
151376


2
10040
3
16800
5
27056
7
42816
11
66592
17
101840
25
152976


2
10168
3
16992
5
27376
8
43304
11
67296
17
102928




2
10296
3
17184
5
27696
8
43816
12
68040
17
104016




2
10424
3
17376
5
28016
8
44328
12
68808
18
104376




2
10552
3
17568
5
28336
8
44840
12
69576
18
105528




2
10680
3
17760
5
28656
8
45352
12
70344
18
106680




2
10808
3
17952
5
28976
8
45864
12
71112
18
107832




2
10936
3
18144
5
29296
8
46376
12
71880
18
108984




2
11064
3
18336
5
29616
8
46888
12
72648
18
110136




2
11192
4
18568
5
29936
8
47400
12
73416
19
110176




2
11320
4
18824
5
30256
8
47912
13
73712
19
111392









The Table 2 satisfies the above equations 1 and 2, and shows that up to the case when one transport block is segmented into 25 code blocks. Within the scope of satisfying the equations 1 and 2, those skilled in the art can easily appreciate an additional transport block (TB) size on the analogy of values shown in Table 2.
Since signal transmission is conducted by the above-mentioned embodiment of the present invention, the addition of dummy bit due to the limitation of the block size of the turbo-encoder can be removed, such that a system performance or throughput can be increased.
Meanwhile, in the case of considering not only a first case in which a transport block is mapped to one code block, but also a second case in which a transport block is segmented into two or more code blocks, the size of an available transport block can be represented by the following Table 3.
















TABLE 3







16
392 
1096
3176
6200
12216
22152
37440
62368
101840


24 
400 
1128
3240
6328 
12384
22408
37888
63072
102928


32 
408 
1160
3304
6456 
12576
22664
38336
63776
104016


40 
416 
1192
3368
6584 
12768
22920
38784
64480
104376


48 
424 
1224
3432
6712 
12960
23176
39232
65184
105528


56 
432 
1256
3496
6840 
13152
23432
39680
65888
106680


64 
440 
1288
3560
6968 
13344
23688
40128
66592
107832


72 
448 
1320
3624
7096 
13536
23944
40576
67296
108984


80 
456 
1352
3688
7224 
13728
24200
41024
68040
110136


88 
464 
1384
3752
7352 
13920
24456
41472
68808
110176


96 
472 
1416
3816
7480 
14112
24496
41920
69576
111392


104
480 
1448
3880
7608
14304
24816
42368
70344
112608


112
488 
1480
3944
7736 
14496
25136
42816
71112
113824


120
504 
1512
4008
7864 
14688
25456
43304
71880
115040


128
520 
1544
4072
7992 
14880
25776
43816
72648
116256


136
536 
1576
4136
8120 
15072
26096
44328
73416
117256


144
552 
1608
4200
8248 
15264
26416
44840
73712
118536


152
568 
1640
4264
8376 
15456
26736
45352
74544
119816


160
584 
1672
4328
8504 
15648
27056
45864
75376
121096


168
600 
1704
4392
8632 
15840
27376
46376
76208
122376


176
616 
1736
4456
8760 
16032
27696
46888
77040
123120


184
632 
1768
4520
8888 
16224
28016
47400
77872
124464


192
648 
1800
4584
9016 
16416
28336
47912
78704
125808


200
664 
1832
4648
9144 
16608
28656
48424
79536
127152


208
680 
1864
4712
9272 
16800
28976
48936
80280
128496


216
696 
1896
4776
9400 
16992
29296
49296
81176
130392


224
712 
1928
4840
9528 
17184
29616
49872
82072
131800


232
728 
1960
4904
9656 
17376
29936
50448
82968
133208


240
744 
1992
4968
9784 
17568
30256
51024
83864
134616


248
760 
2024
5032
9912 
17760
30576
51600
84760
134848


256
776 
2088
5096
10040
17952
30936
52176
85656
136320


264
792 
2152
5160
10168
18144
31320
52752
86016
137792


272
808
2216
5224
10296
18336
31704
53328
86976 
139264


280
824
2280
5288
10424
18568
32088
53904
87936 
140736


288
840
2344
5352
10552
18824
32472
54480
88896 
142248


296
856
2408
5416
10680
19080
32856
55056
89856 
143784


304
872
2472
5480
10808
19336
33240
55416
90816 
145320


312
888
2536
5544
10936
19592
33624
56056
91776 
146856


320
904
2600
5608
11064
19848
34008
56696
92776 
148176


328
920
2664
5672
11192
20104
34392
57336
93800 
149776


336
936
2728
5736
11320
20360
34776
57976
94824 
151376


344
952
2792
5800
11448
20616
35160
58616
95848 
152976


352
968
2856
5864
11576
20872
35544
59256
96872



360
984
2920
5928
11704
21128
35928
59896
97896



368
1000 
2984
5992
11832
21384
36312
60536
98576



376
1032 
3048
6056
11960
21640
36696
61176
99664



384
1064 
3112
6120
12088
21896
36992
61664
100752









When implementing the above described methodology, when a terminal identifies that the length of the CRC-attached transport block is larger than the largest interleaver block size, the terminal may determine the predetermined number of code blocks from a look-up table (as seen in step S601 of FIG. 6) or may calculate the predetermined number of code blocks based upon a formula. The calculation may include calculating the predetermined number of code blocks based on the following equation:

C=┌B/(Z−L)┐, where

┌ ┐ represents a ceiling function,
C is the predetermined number of code blocks,
B is the length of the CRC-attached transport block,
Z is the largest interleaver block size, and
L is the first CRC length.
A signal transmission method and device according to this embodiment enables the transport block to have a predetermined length corresponding to any one of various values shown in Table 3. Table 3 shows the available transport block (TB) sizes which obviates the need for the conventional practice of inserting the dummy bit into the signal. The signal transmission method may allow sub-sets of Table 3 to be shared between a transmission end and a reception end in consideration of signaling overhead and the like, instead of using all the values of Table 36.
In the meantime, in order to inform the reception end of the transport block size, the transmission end is able to represent the transport block size by a combination of a modulation and coding scheme (MCS), and the size of allocated resources (as seen in step S603 of FIG. 6). By means of a channel quality indicator transferred from the reception end, a scheduler decides the MCS. The size of allocated resources is decided in consideration of not only resources for transferring control information but also other resources for a reference signal for channel estimation. As noted above, the code block is mapped to a transport block with the transport block size (S605).
FIG. 5 shows an example of a resource structure according to the present invention.
Referring to FIG. 5, a horizontal axis indicates a time domain, and a vertical axis indicates a frequency domain. On the assumption that the resource structure of FIG. 5 is used, it is assumed that the resources for transferring control information correspond to 3 symbols and two transmission (Tx) antennas are used, one resource block (RB) includes 120 resource elements (REs) capable of being used to transmit data.
In this case, if it is assumed that the modulation rate is 64 QAM, the coding rate is 0.6504, and the number of allocated resource blocks (RBs) is 10, the size of a data block capable of being transmitted is 4658 bits. These 4658 bits are located between 4608 bits and 4672 bits of Table 1. If it is assumed that the size of the transmittable data block is set to the 4608 bits or the 4672 bits, the data block size can be decided by various modulation and coding rates and the size of allocated resources.
As previously described in the above-mentioned example, if the size of an actually-transmittable data block is different from the size of a supportable data block, the size of the actually-transmittable data block can be decided by any of the following rules i) ̃iii):
A method for deciding the actually-transmittable data block size as a maximally-supportable data block size which is equal to or smaller than the actually-transmittable data block size;
A method for deciding the actually-transmittable data block size as a minimally-supportable data block size larger than the actually-transmittable data block size; and
A method for deciding the actually-transmittable data block size as a supportable data block size which has a minimum difference with the actually-transmittable data block size.
In this case, if one transport block is transferred via one code block, the data block may correspond to the transport block. Otherwise, if one transport block is transferred via two or more code blocks, the data block may be considered to be the code blocks.
It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents. For example, although the signal transmission method according to the present invention has been disclosed on the basis of the 3GPP LTE system, it can also be applied to other communication systems, each of which has a limitation in the block size during the encoding process and uses a combination of predetermined transport block sizes.
If a transport block received from an upper layer is segmented into a plurality of code blocks, and the code blocks are encoded by a turbo-encoder, the signal transmission method according to the present invention is able to remove the added dummy bits caused by a limitation of the block size of the internal interleaver of the turbo-encoder, such that it can effectively transmit signals.

## Claims

1. A method for performing, by a first device, channel coding of data to be transmitted to a second device, the method comprising:
determining a size of a transport block for the data;
attaching a first cyclic redundancy check (CRC) code to the transport block having the determined size to produce a first CRC-attached transport block; and
segmenting the first CRC-attached transport block into multiple code blocks,
wherein the size of the transport block is determined from among a plurality of predetermined transport block sizes, and
wherein the plurality of predetermined transport block sizes are predetermined such that all the multiple code blocks have a same size as each other.

2. The method of claim 1, further comprising:
attaching a second CRC code to each of the multiple code blocks; and
encoding the second CRC-attached code blocks by a turbo-encoder.

3. The method of claim 2, wherein the plurality of transport block sizes satisfy that the multiple code blocks have the same size which is equal to one of a plurality of predefined block sizes of an internal interleaver minus a size of the second CRC code.

4. The method of claim 1, wherein the plurality of predetermined transport block sizes comprise 6200, 6456, 6712, 6968, 7224, 7480, 7736, 7992, 8248, 8504, 8760, 9144, 9528, 9912, 10296, 10680, 11064, 11448, 11832, 12216, 12576, 12960, 13536, 14112, 14688, 15264, 15840, 16416, 16992, 17568, 18336, 19080, 19848, 20616, 21384, 22152, 22920, 23688, 24496, 25456, 26416, 27376, 28336, 29296, 30576, 31704, 32856, 34008, 35160, 36696, 37888, 39232, 40576, 42368, 43816, 45352, 46888, 51024, 52752, 57336, 59256, 61664, 63776, 66592, 68808, 71112, and 75376.

5. The method of claim 2, wherein a size of each of the first and second CRC codes is 24.

6. A device for performing channel coding of data to be transmitted to an external apparatus, the device comprising:
a processor configured to:
determine a size of a transport block for the data;
attach a first cyclic redundancy check (CRC) code to the transport block having the determined size to produce a first CRC-attached transport block; and
segment the first CRC-attached transport block into multiple code blocks,
wherein the processor is configured to determine the size of the transport block from among a plurality of predetermined transport block sizes, and
wherein the plurality of predetermined transport block sizes are predetermined such that all the multiple code blocks have a same size as each other.

7. The device of claim 6, further comprising:
a turbo-encoder,
wherein the processor is configured to attach a second CRC code to each of the multiple code blocks and control the turbo-encoder to encode the second CRC-attached code blocks.

8. The device of claim 7, wherein:
the turbo-encoder includes an internal interleaver, and
the plurality of predetermined transport block sizes satisfy that the multiple code blocks have the same size which is equal to one of a plurality of predefined block sizes of the internal interleaver minus a size of the second CRC code.

9. The device of claim 6, wherein the plurality of predetermined transport block sizes comprise 6200, 6456, 6712, 6968, 7224, 7480, 7736, 7992, 8248, 8504, 8760, 9144, 9528, 9912, 10296, 10680, 11064, 11448, 11832, 12216, 12576, 12960, 13536, 14112, 14688, 15264, 15840, 16416, 16992, 17568, 18336, 19080, 19848, 20616, 21384, 22152, 22920, 23688, 24496, 25456, 26416, 27376, 28336, 29296, 30576, 31704, 32856, 34008, 35160, 36696, 37888, 39232, 40576, 42368, 43816, 45352, 46888, 51024, 52752, 57336, 59256, 61664, 63776, 66592, 68808, 71112, and 75376.

10. The device of claim 7, wherein a size of each of the first and second CRC codes is 24.