Data processing device and data processing method
View Patent ↗The present technology relates to a data processing device and a data processing method so that an LDPC code with a good bit error rate is provided. An LDPC encoder encodes by an LDPC code whose code length is 16200 bits and code rate is 10/15. The LDPC code includes information bits and parity bits. A parity check matrix H includes an information matrix part corresponding to the information bits of the LDPC code and a parity matrix part corresponding to the parity bits. The information matrix part of the parity check matrix H is represented by a parity check matrix initial value table that indicates a position of an element 1 of the information matrix part for each 360 columns. The present technology is applicable to a case in which LDPC encoding and LDPC decoding are performed.
1. A transmitting device for generating a terrestrial digital television broadcast signal, the device decreasing a signal-to-noise power ratio per symbol for a selected bit error rate of the generated terrestrial digital television broadcast signal and/or expanding reception range of the terrestrial digital television broadcast signal at which the data is decodable by a receiving device for presentation to a user, the device comprising:
circuitry configured to:
receive data to be transmitted in a terrestrial digital television broadcast signal;
perform LDPC (low density parity check) encoding on input bits of the received data according to a parity check matrix initial value table of an LDPC code having a code length of 16200 bits and a code rate of 10/15 to generate an LDPC code word, the LDPC code enabling error correction processing to correct errors generated in a transmission path of the terrestrial digital television broadcast signal;
wherein
the LDPC code word includes information bits and parity bits, the parity bits being processed by the receiving device to recover information bits corrupted by transmission path errors,
the parity check matrix includes an information matrix portion corresponding to the information bits and a parity matrix portion corresponding to the parity bits,
the information matrix portion is represented by a parity check matrix initial value table, and
the parity check matrix initial value table, having each row indicating positions of elements ‘1’ in corresponding 360 columns of the information matrix portion as a subset of information bits used in calculating the parity bits in the LDPC encoding, is as follows
352 747 894 1437 1688 1807 1883 2119 2159 3321 3400 3543 3588 3770 3821 4384 4470 4884 5012 5036 5084 5101 5271 5281 5353
505 915 1156 1269 1518 1650 2153 2256 2344 2465 2509 2867 2875 3007 3254 3519 3687 4331 4439 4532 4940 5011 5076 5113 5367
268 346 650 919 1260 4389 4653 4721 4838 5054 5157 5162 5275 5362
220 236 828 1590 1792 3259 3647 4276 4281 4325 4963 4974 5003 5037
381 737 1099 1409 2364 2955 3228 3341 3473 3985 4257 4730 5173 5242
88 771 1640 1737 1803 2408 2575 2974 3167 3464 3780 4501 4901 5047
749 1502 2201 3189
2873 3245 3427
2158 2605 3165
1 3438 3606
10 3019 5221
371 2901 2923
9 3935 4683
1937 3502 3735
507 3128 4994
25 3854 4550
1178 4737 5366
2 223 5304
1146 5175 5197
1816 2313 3649
740 1951 3844
1320 3703 4791
1754 2905 4058
7 917 5277
3048 3954 5396
4804 4824 5105
2812 3895 5226
0 5318 5358
1483 2324 4826
2266 4752 5387; and
a terrestrial broadcast transmitter configured to transmit the digital television broadcast signal including the LDPC code word.
2. The transmitting device according to claim 1 , wherein
the parity check matrix has no cycle-4.
3. The transmitting device according to claim 1 , wherein
the parity check matrix of the LDPC code belongs to an ensemble in which a performance threshold being a ratio of signal power to noise power at which a bit error rate starts to decrease is a predetermined value or smaller is found by multi-edge type density evolution.
4. A method for generating a terrestrial digital television broadcast signal, the method decreasing a signal-to-noise power ratio per symbol for a selected bit error rate of the generated terrestrial digital television broadcast signal and/or expanding reception range of the terrestrial digital television broadcast signal at which the data is decodable by a receiving device for presentation to a user, the method comprising:
receiving data to be transmitted in a terrestrial digital television broadcast signal;
performing low density parity check (LDPC) encoding, in an LDPC encoding circuitry, on input bits of the received data according to a parity check matrix of an LDPC code having a code length of 16200 bits and a code rate of 10/15 to generate an LDPC code word, the LDPC code enabling error correction processing to correct errors generated in a transmission path of the terrestrial digital television broadcast signal;
wherein the LDPC code word includes information bits and parity bits, the parity bits being processed by the receiving device to recover information bits corrupted by transmission path errors,
the parity check matrix includes an information matrix portion corresponding to the information bits and a parity matrix portion corresponding to the parity bits,
the information matrix portion is represented by a parity check matrix initial value table, and
the parity check matrix initial value table, having each row indicating positions of elements ‘1’ in corresponding 360 columns of the information matrix portion as a subset of information bits used in calculating the parity bits in the LDPC encoding, is as follows:
352 747 894 1437 1688 1807 1883 2119 2159 3321 3400 3543 3588 3770 3821 4384 4470 4884 5012 5036 5084 5101 5271 5281 5353
505 915 1156 1269 1518 1650 2153 2256 2344 2465 2509 2867 2875 3007 3254 3519 3687 4331 4439 4532 4940 5011 5076 5113 5367
268 346 650 919 1260 4389 4653 4721 4838 5054 5157 5162 5275 5362
220 236 828 1590 1792 3259 3647 4276 4281 4325 4963 4974 5003 5037
381 737 1099 1409 2364 2955 3228 3341 3473 3985 4257 4730 5173 5242
88 771 1640 1737 1803 2408 2575 2974 3167 3464 3780 4501 4901 5047
749 1502 2201 3189
2873 3245 3427
2158 2605 3165
1 3438 3606
10 3019 5221
371 2901 2923
9 3935 4683
1937 3502 3735
507 3128 4994
25 3854 4550
1178 4737 5366
2 223 5304
1146 5175 5197
1816 2313 3649
740 1951 3844
1320 3703 4791
1754 2905 4058
7 917 5277
3048 3954 5396
4804 4824 5105
2812 3895 5226
0 5318 5358
1483 2324 4826
2266 4752 5387; and
transmitting, by a terrestrial broadcast transmitter, the digital television broadcast signal including the LDPC code word.
5. A receiving device for use in an environment where a signal-to-noise power ratio per symbol for a selected bit error rate of the received terrestrial digital television broadcast signal can be reduced and/or a reception range of a terrestrial digital television broadcast signal can be expanded, the receiving device comprising:
a tuner configured to receive a terrestrial digital television broadcast signal including a low density parity check (LDPC) code word; and
circuitry configured to:
decode the LDPC code word; and
process the decoded LDPC code word for presentation to a user, wherein
input bits of data to be transmitted in the terrestrial digital television broadcast signal are LDPC encoded according to
a parity check matrix initial value table of an LDPC code having a code length of 16200 bits and a code rate of 10/15 to generate the LDPC code word, the LDPC code enabling error correction processing to correct errors generated in a transmission path of the terrestrial digital television broadcast signal,
the LDPC code word includes information bits and parity bits, the parity bits being processed by the receiving device to recover information bits corrupted by transmission path errors,
wherein the parity check matrix initial value table of the LDPC code according to which the input bits are LDPC encoded is as follows,
352 747 894 1437 1688 1807 1883 2119 2159 3321 3400 3543 3588 3770 3821 4384 4470 4884 5012 5036 5084 5101 5271 5281 5353
505 915 1156 1269 1518 1650 2153 2256 2344 2465 2509 2867 2875 3007 3254 3519 3687 4331 4439 4532 4940 5011 5076 5113 5367
268 346 650 919 1260 4389 4653 4721 4838 5054 5157 5162 5275 5362
220 236 828 1590 1792 3259 3647 4276 4281 4325 4963 4974 5003 5037
381 737 1099 1409 2364 2955 3228 3341 3473 3985 4257 4730 5173 5242
88 771 1640 1737 1803 2408 2575 2974 3167 3464 3780 4501 4901 5047
749 1502 2201 3189
2873 3245 3427
2158 2605 3165
1 3438 3606
10 3019 5221
371 2901 2923
9 3935 4683
1937 3502 3735
507 3128 4994
25 3854 4550
1178 4737 5366
2 223 5304
1146 5175 5197
1816 2313 3649
740 1951 3844
1320 3703 4791
1754 2905 4058
7 917 5277
3048 3954 5396
4804 4824 5105
2812 3895 5226
0 5318 5358
1483 2324 4826
2266 4752 5387.
6. The receiving device according to claim 5 , wherein
the LDPC code word is encoded based on a parity check matrix of a LDPC code,
the parity check matrix includes an information matrix part corresponding to the information bits and a parity matrix part corresponding to the parity bits,
the information matrix part being represented by the parity check matrix initial value table, and
each row of the parity check matrix initial value table indicates positions of elements “1” in corresponding 360 columns of the information matrix part as a subset of information bits used in calculating the parity bits in the LDPC encoding.
7. The receiving device according to claim 6 , wherein
if a row of the parity check matrix initial value table is represented by i and a length of the parity bits of the LDPC code word is represented by M, the 2+360×(i−1)-th column of the parity check matrix is obtained by the cyclic shift of the 1+360×(i−1)-th column of the parity check matrix indicating a position of an element 1 in the parity check matrix initial value table downward by q=M/360.
8. The receiving device according to claim 7 , wherein
for the 1+360×(i−1)-th column of the parity check matrix,
an i-th row of the parity check matrix initial value table represents the row number of the element 1 of the 1+360×(i−1)-th column of the parity check matrix, and
for each column from the 2+360×(i−1)-th column to a 360×i-th column being a column other than the 1+360×(i−1)-th column of the parity check matrix,
if an i-th row and j-th column value of the parity check matrix initial value table is represented as h i,j and the row number of a j-th element 1 of a w-th column of the parity check matrix H is represented as H w-j ,
a row number H w-j of the element 1 of the w-th column being a column other than the 1+360×(i−1)-th column of the parity check matrix is represented by the equation
H w-j =mod( h i,j +mod(( w− 1), 360)× M/ 360, M ).
9. The receiving device according to claim 6 , wherein the circuitry is further configured to:
interleave only parity bits of the LDPC code word.
10. The receiving device according to claim 6 , wherein
the parity check matrix has no cycle-4.
11. The receiving device according to claim 6 , wherein
the parity check matrix of the LDPC code belongs to an ensemble in which a performance threshold being a ratio of signal power to noise power at which a bit error rate starts to decrease is a predetermined value or smaller is found by multi-edge type density evolution.
12. The transmitting device according to claim 1 , wherein
if a row of the parity check matrix initial value table is represented by i and a length of the parity bits of the LDPC code word is represented by M, the 2+360×(i−1)-th column of the parity check matrix is obtained by the cyclic shift of the 1+360×(i−1)-th column of the parity check matrix indicating a position of an element 1 in the parity check matrix initial value table downward by q=M/360.
13. The transmitting device according to claim 12 , wherein
for the 1+360×(i−1)-th column of the parity check matrix,
an i-th row of the parity check matrix initial value table represents the row number of the element 1 of the 1+360×(i−1)-th column of the parity check matrix, and
for each column from the 2+360×(i−1)-th column to a 360 ×i-th column being a column other than the 1+360×(i−1)-th column of the parity check matrix,
if an i-th row and j-th column value of the parity check matrix initial value table is represented as h i,j and the row number of a j-th element 1 of a w-th column of the parity check matrix H is represented as H w-j ,
a row number H w-j , of the element 1 of the w-th column being a column other than the 1+360×(i−1)-th column of the parity check matrix is represented by the equation
H w-j =mod( h i,j +mod(( w− 1), 360)× M/ 360, M ).
14. A method for use by a receiving device in an environment where a signal-to-noise power ratio per symbol for a selected bit error rate of a terrestrial digital television broadcast signal can be reduced and/or a reception range of a terrestrial digital television broadcast signal can be expanded, the method comprising:
receiving, by a tuner, a terrestrial digital television broadcast signal including an LDPC (low density parity check) code word;
decoding, by decoding circuitry, the LDPC code word; and
processing the decoded LDPC code word for presentation to a user, wherein
input bits of data to be transmitted in the terrestrial digital television broadcast signal are LDPC encoded according to a parity check matrix initial value table of an LDPC code having a code length N of 16200 bits and a code rate r of 10/15 to generate the LDPC code word, the LDPC code enabling error correction processing to correct errors generated in a transmission path of the terrestrial digital television broadcast signal,
the LDPC code word includes information bits and parity bits, the parity bits being processed by the receiving device to recover information bits corrupted by transmission path errors,
the parity check matrix initial value table of the LDPC code according to which the input bits are LDPC encoded is as follows,
352 747 894 1437 1688 1807 1883 2119 2159 3321 3400 3543 3588 3770 3821 4384 4470 4884 5012 5036 5084 5101 5271 5281 5353
505 915 1156 1269 1518 1650 2153 2256 2344 2465 2509 2867 2875 3007 3254 3519 3687 4331 4439 4532 4940 5011 5076 5113 5367
268 346 650 919 1260 4389 4653 4721 4838 5054 5157 5162 5275 5362
220 236 828 1590 1792 3259 3647 4276 4281 4325 4963 4974 5003 5037
381 737 1099 1409 2364 2955 3228 3341 3473 3985 4257 4730 5173 5242
88 771 1640 1737 1803 2408 2575 2974 3167 3464 3780 4501 4901 5047
749 1502 2201 3189
2873 3245 3427
2158 2605 3165
1 3438 3606
10 3019 5221
371 2901 2923
9 3935 4683
1937 3502 3735
507 3128 4994
25 3854 4550
1178 4737 5366
2 223 5304
1146 5175 5197
1816 2313 3649
740 1951 3844
1320 3703 4791
1754 2905 4058
7 917 5277
3048 3954 5396
4804 4824 5105
2812 3895 5226
0 5318 5358
1483 2324 4826 2266 4752 5387.
15. The method according to claim 14 , wherein
the LDPC code word is encoded based on a parity check matrix of a LDPC code,
the parity check matrix includes an information matrix part corresponding to the information bits and a parity matrix part corresponding to the parity bits,
the information matrix part being represented by the parity check matrix initial value table, and
each row of the parity check matrix initial value table indicates positions of elements “1” in corresponding 360 columns of the information matrix part as a subset of information bits used in calculating the parity bits in the LDPC encoding.
16. The method according to claim 15 , wherein
if a row of the parity check matrix initial value table is represented by i and a length of the parity bits of the LDPC code word is represented by M, the 2+360×(i−1)-th column of the parity check matrix is obtained by the cyclic shift of the 1+360×(i−1)-th column of the parity check matrix indicating a position of an element 1 in the parity check matrix initial value table downward by q=M/360.
17. The method according to claim 16 , wherein
for the 1+360×(i−1)-th column of the parity check matrix,
an i-th row of the parity check matrix initial value table represents the row number of the element 1 of the 1+360×(i−1)-th column of the parity check matrix, and
for each column from the 2+360×(i−1)-th column to a 360 ×i-th column being a column other than the 1+360×(i−1)-th column of the parity check matrix,
if an i-th row and j-th column value of the parity check matrix initial value table is represented as h i,j and the row number of a j-th element 1 of a w-th column of the parity check matrix H is represented as H w-j ,
a row number H w-j of the element 1 of the w-th column being a column other than the 1+360×(i−1)-th column of the parity check matrix is represented by the equation
H w-j =mod( h i,j +mod(( w− 1) , 360)× M/ 360, M ).
18. The method according to claim 15 , wherein
the parity check matrix has no cycle-4.
19. The data processing device method according to claim 15 , wherein
the parity check matrix of the LDPC code belongs to an ensemble in which a performance threshold being signal power/noise power at which a bit error rate starts to decrease is a predetermined value or smaller is found by multi-edge type density evolution.
20. A non-transitory computer readable medium including computer executable instructions which, when executed by a computer, cause the computer to perform a method for generating a terrestrial digital television broadcast signal, the method decreasing a signal-to-noise power ratio per symbol for a selected bit error rate of the generated terrestrial digital television broadcast signal and/or expanding reception range of the terrestrial digital television broadcast signal at which the data is decodable by a receiving device for presentation to a user, the method comprising:
receiving data to be transmitted in a terrestrial digital television broadcast signal;
performing LDPC (low density parity check) encoding on input bits of the received data according to a parity check matrix initial value table of an LDPC code having a code length of 16200 bits and a code rate of 10/15 to generate the LDPC code word, the LDPC code enabling error correction processing to correct errors generated in a transmission path of the terrestrial digital television broadcast signal,
wherein
the LDPC code word includes information bits and parity bits, the parity bits being processed by the receiving device to recover information bits corrupted by transmission path errors,
the parity check matrix initial value table of the LDPC code according to which the input bits are LDPC encoded is as follows,
352 747 894 1437 1688 1807 1883 2119 2159 3321 3400 3543 3588 3770 3821 4384 4470 4884 5012 5036 5084 5101 5271 5281 5353
505 915 1156 1269 1518 1650 2153 2256 2344 2465 2509 2867 2875 3007 3254 3519 3687 4331 4439 4532 4940 5011 5076 5113 5367
268 346 650 919 1260 4389 4653 4721 4838 5054 5157 5162 5275 5362
220 236 828 1590 1792 3259 3647 4276 4281 4325 4963 4974 5003 5037
381 737 1099 1409 2364 2955 3228 3341 3473 3985 4257 4730 5173 5242
88 771 1640 1737 1803 2408 2575 2974 3167 3464 3780 4501 4901 5047
749 1502 2201 3189
2873 3245 3427
2158 2605 3165
1 3438 3606
10 3019 5221
371 2901 2923
9 3935 4683
1937 3502 3735
507 3128 4994
25 3854 4550
1178 4737 5366
2 223 5304
1146 5175 5197
1816 2313 3649
740 1951 3844
1320 3703 4791
1754 2905 4058
7 917 5277
3048 3954 5396
4804 4824 5105
2812 3895 5226
0 5318 5358
1483 2324 4826
2266 4752 5387;and
transmitting the digital television broadcast signal including the LDPC code word.
21. A non-transitory computer readable medium including computer executable instructions which, when executed by a computer, cause the computer to perform a method for use by a receiving device in an environment where a signal-to-noise power ratio per symbol for a selected bit error rate of a terrestrial digital television broadcast signal can be reduced and/or a reception range of a terrestrial digital television broadcast signal can be expanded, the method comprising:
receiving, by a tuner, a terrestrial digital television broadcast signal including an LDPC (low density parity check) code word;
decoding the LDPC code word; and
processing the decoded LDPC code word for presentation to a user, wherein
input bits of data to be transmitted in the terrestrial digital television broadcast signal are LDPC encoded according to a parity check matrix initial value table of an LDPC code having a code length N of 16200 bits and a code rate r of 10/15 to generate the LDPC code word, the LDPC code enabling error correction processing to correct errors generated in a transmission path of the terrestrial digital television broadcast signal,
the LDPC code word includes information bits and parity bits, the parity bits being processed by the receiving device to recover information bits corrupted by transmission path errors,
the parity check matrix initial value table of the LDPC code according to which the input bits are LDPC encoded is as follows,
352 747 894 1437 1688 1807 1883 2119 2159 3321 3400 3543 3588 3770 3821 4384 4470 4884 5012 5036 5084 5101 5271 5281 5353
505 915 1156 1269 1518 1650 2153 2256 2344 2465 2509 2867 2875 3007 3254 3519 3687 4331 4439 4532 4940 5011 5076 5113 5367
268 346 650 919 1260 4389 4653 4721 4838 5054 5157 5162 5275 5362
220 236 828 1590 1792 3259 3647 4276 4281 4325 4963 4974 5003 5037
381 737 1099 1409 2364 2955 3228 3341 3473 3985 4257 4730 5173 5242
88 771 1640 1737 1803 2408 2575 2974 3167 3464 3780 4501 4901 5047
749 1502 2201 3189
2873 3245 3427
2158 2605 3165
1 3438 3606
10 3019 5221
371 2901 2923
9 3935 4683
1937 3502 3735
507 3128 4994
25 3854 4550
1178 4737 5366
2 223 5304
1146 5175 5197
1816 2313 3649
740 1951 3844
1320 3703 4791
1754 2905 4058
7 917 5277
3048 3954 5396
4804 4824 5105
2812 3895 5226
0 5318 5358
1483 2324 4826
2266 4752 5387.