Method and apparatus for channel encoding and decoding in a communication system using low-density parity-check codes

A method for encoding a channel in a communication system using a Low-Density Parity-Check (LDPC) code in a transmitter including a puncturing pattern applier, the method comprising:

• determining, by the puncturing pattern applier, a number of parity bits for puncturing;
• performing puncturing on the determined number of the parity bits according to a predetermined puncturing pattern;
• and
• transmitting, by the transmitter, remaining bits, except for the punctured bits;
• wherein puncturing is applied to an LDPC code with a codeword length of 16200 and an information length of 3240 in accordance with a puncturing pattern defined as shown in the following table;
• Major variables
• N1 = 16200, K1 = 3240, M1 = 360, q = 36
• of DVB-S2
• LDPC code
• Define a set Pj satisfying the characteristics
• Grouping of
• for 0 ≦ j < q = 36:
• parity bits
• Pj = {pk|k ≡ j mod 36, 0 ≦ k < 12960}.
• Pj is a set having 360 parity bits as its entries.
• Range of Np
• Puncturing Method
• 0 ≦ Np < 12960
• For
• ⁢
• ⁢
• an
• ⁢
• ⁢
• integer
• ⁢
• ⁢
• m
• =
• ⌊
• N
• p
• 360
• ⌋
• ,
• puncture
• ⁢
• ⁢
• ⁢
• all
• ⁢
• ⁢
• of
• ⁢
• ⁢
• parity
• bits corresponding to m parity bit sets Pπ(0), Pπ(1), . . . , Pπ(m−1), and additionally puncture (Np − 360 m) parity bits among the parity bits corresponding to Pπ(m). π indicates a permutation function that is a puncturing pattern, and parity bits corresponding to parity bit sets are shown at the bottom of the table.
• π(0)
• π(1)
• π(2)
• π(3)
• π(4)
• π(5)
• π(6)
• π(7)
• π(8)
• 27
• 13
• 29
• 32
• 5
• 0
• 11
• 21
• 33
• π(9)
• π(10)
• π(11)
• π(12)
• π(13)
• π(14)
• π(15)
• π(16)
• π(17)
• 20
• 25
• 28
• 18
• 35
• 8
• 3
• 9
• 31
• π(18)
• π(19)
• π(20)
• π(21)
• π(22)
• π(23)
• π(24)
• π(25)
• π(26)
• 22
• 24
• 7
• 14
• 17
• 4
• 2
• 26
• 16
• π(27)
• π(28)
• π(29)
• π(30)
• π(31)
• π(32)
• π(33)
• π(34)
• π(35)
• 34
• 19
• 10
• 12
• 23
• 1
• 6
• 30
• 15
• where N1 denotes a length of an LDPC codeword, K1 denotes a length of an information word, M1 denotes a length of one column group, and q is an integer satisfying q=(N1-K1)/M1, where K1/M1 is an integer.

A method for encoding a channel in a communication system using a Low-Density Parity-Check (LDPC) code in a transmitter including a puncturing pattern applier, the method comprising:

• determining, by the puncturing pattern applier, a number of parity bits for puncturing;
• performing puncturing on the determined number of parity bits according to a predetermined puncturing pattern;
• and
• transmitting, by the transmitter, remaining bits, except for the punctured bits;
• wherein puncturing is applied to an LDPC code with a codeword length of 16200 and an information length of 7200 in accordance with a puncturing pattern defined as shown the following table;
• Major variables
• N1 = 16200, K1 = 7200, M1 = 360, q = 25
• of DVB-S2
• LDPC code
• Define a set Pj satisfying characteristics
• Grouping of
• for 0 ≦ j < q = 25:
• parity bits
• Pj = {pk|k ≡ j mod 25, 0 ≦ k < 9000}.
• Pj is a set having 360 parity bits as its entries.
• Range of Np
• Puncturing Method
• 0 ≦ Np < 9000
• For
• ⁢
• ⁢
• an
• ⁢
• ⁢
• integer
• ⁢
• ⁢
• m
• =
• ⌊
• N
• p
• 360
• ⌋
• ,
• puncture
• ⁢
• ⁢
• ⁢
• all
• ⁢
• ⁢
• of
• ⁢
• ⁢
• parity
• bits corresponding to m parity bit sets Pπ(0), Pπ(1), . . . , Pπ(m−1), and additionally puncture (Np − 360 m) parity bits among the parity bits corresponding to Pπ(m). π indicates a permutation function that is a puncturing pattern, and parity bits corresponding to parity bit sets are shown at the bottom of the table.
• π(0)
• π(1)
• π(2)
• π(3)
• π(4)
• π(5)
• π(6)
• π(7)
• π(8)
• 6
• 4
• 18
• 9
• 13
• 8
• 15
• 20
• 5
• π(9)
• π(10)
• π(11)
• π(12)
• π(13)
• π(14)
• π(15)
• π(16)
• π(17)
• 17
• 2
• 24
• 10
• 22
• 12
• 3
• 16
• 23
• π(18)
• π(19)
• π(20)
• π(21)
• π(22)
• π(23)
• π(24)
• —
• —
• 1
• 14
• 0
• 21
• 19
• 7
• 11
• —
• —
• where N1 denotes a length of an LDPC codeword, IC1 denotes a length of an information word, M1 denotes a length of one column group, and q is an integer satisfying q=(N1-K1)/M1, where K1/M1 is an integer.

An apparatus for encoding a channel in a communication system using a Low-Density Parity-Check (LDPC) code, the apparatus comprising:

• a puncturing pattern applier for determining a number of parity bits for puncturing, and performing puncturing on the determined number of parity bits according to a predetermined puncturing pattern;
• and
• a transmission unit for transmitting remaining bits, except for the punctured bits;
• wherein puncturing is applied to an LDPC code with a codeword length of 16200 and an information length of 3240 in accordance with a puncturing pattern defined as shown in the following table;
• Major variables of
• N1 = 16200, K1 = 3240, M1 = 360, q = 36
• DVB-S2 LDPC code
• Grouping of
• Define a set Pj satisfying characteristics
• parity bits
• for 0 ≦ j < q = 36:
• Pj = {pk|k ≡ j mod 36, 0 ≦ k < 12960}.
• Pj is a set having 360 parity bits as its entries.
• Range of Np
• Puncturing Method
• 0 ≦ Np < 12960
• For
• ⁢
• ⁢
• an
• ⁢
• ⁢
• integer
• ⁢
• ⁢
• m
• =
• ⌊
• N
• p
• 360
• ⌋
• ,
• puncture
• ⁢
• ⁢
• ⁢
• all
• ⁢
• ⁢
• of
• ⁢
• ⁢
• parity
• bits corresponding to m parity bit sets Pπ(0), Pπ(1), . . . , Pπ(m−1), and additionally puncture (Np − 360 m) parity bits among the parity bits corresponding to Pπ(m). Here, π indicates a permutation function that is a puncturing pattern, and parity bits corresponding to parity bit sets are shown at the bottom of the table.
• π(0)
• π(1)
• π(2)
• π(3)
• π(4)
• π(5)
• π(6)
• π(7)
• π(8)
• 27
• 13
• 29
• 32
• 5
• 0
• 11
• 21
• 33
• π(9)
• π(10)
• π(11)
• π(12)
• π(13)
• π(14)
• π(15)
• π(16)
• π(17)
• 20
• 25
• 28
• 18
• 35
• 8
• 3
• 9
• 31
• π(18)
• π(19)
• π(20)
• π(21)
• π(22)
• π(23)
• π(24)
• π(25)
• π(26)
• 22
• 24
• 7
• 14
• 17
• 4
• 2
• 26
• 16
• π(27)
• π(28)
• π(29)
• π(30)
• π(31)
• π(32)
• π(33)
• π(34)
• π(35)
• 34
• 19
• 10
• 12
• 23
• 1
• 6
• 30
• 15
• where N1 denotes a length of an LDPC codeword, K1 denotes a length of an information word, M1 denotes a length of one column group, and q is an integer satisfying q=(N1-K1)/M1, where K1/M1 is an integer.

An apparatus for encoding a channel in a communication system using a Low-Density Parity-Check (LDPC) code, the apparatus comprising:

• a puncturing pattern applier for determining a number of parity bits for puncturing, and performing puncturing on the determined number of parity bits according to a predetermined puncturing pattern;
• and
• a transmission unit for transmitting remaining bits, except for the punctured bits;
• wherein puncturing is applied to an LDPC code with a codeword length of 16200 and an information length of 7200 in accordance with a puncturing pattern defined as shown in the following table;
• Major variables of
• N1 = 16200, K1 = 7200, M1 = 360, q = 25
• DVB-S2 LDPC code
• Grouping of
• Define a set Pj satisfying
• parity bits
• characteristics for 0 ≦ j < q = 25:
• Pj = {pk|k ≡ j mod 25, 0 ≦ k < 9000}.
• The set Pj is a set having 360 parity bits as
• its entries.
• Range of Np
• Puncturing Method
• 0 ≦ Np < 9000
• For
• ⁢
• ⁢
• an
• ⁢
• ⁢
• integer
• ⁢
• ⁢
• m
• =
• ⌊
• N
• p
• 360
• ⌋
• ,
• puncture
• ⁢
• ⁢
• ⁢
• all
• ⁢
• ⁢
• of
• ⁢
• ⁢
• parity
• bits corresponding to m parity bit sets Pπ(0), Pπ(1), . . . , Pπ(m−1), and additionally puncture (Np − 360 m) parity bits among the parity bits corresponding to Pπ(m). Here, π indicates a permutation function that is a puncturing pattern, and parity bits corresponding to parity bit sets are shown at the bottom of the table.
• π(0)
• π(1)
• π(2)
• π(3)
• π(4)
• π(5)
• π(6)
• π(7)
• π(8)
• 6
• 4
• 18
• 9
• 13
• 8
• 15
• 20
• 5
• π(9)
• π(10)
• π(11)
• π(12)
• π(13)
• π(14)
• π(15)
• π(16)
• π(17)
• 17
• 2
• 24
• 10
• 22
• 12
• 3
• 16
• 23
• π(18)
• π(19)
• π(20)
• π(21)
• π(22)
• π(23)
• π(24)
• —
• —
• 1
• 14
• 0
• 21
• 19
• 7
• 11
• —
• —
• where N1 denotes a length of an LDPC codeword, K1 denotes a length of an information word, M1 denotes a length of one column group, and q is an integer satisfying q=(N1-K1)/M1, where K1/M1 is an integer.

A method for decoding a channel in a communication system using a Low-Density Parity-Check (LDPC) code, the method comprising:

• demodulating a signal transmitted from a transmitter;
• determining if there are any punctured bits in the demodulated signal;
• determining positions of punctured parity bits by estimating information on a puncturing pattern, when there are punctured bits in the demodulated signal;
• and
• decoding data using the determined positions of the punctured parity bits,
• wherein the determining positions of the punctured bits comprises:
• determining a number of punctured bits;
• and
• determining positions of punctured bits corresponding to the determined number of the punctured bits in consideration of a predetermined interval,
• wherein the predetermined interval is determined by dividing a length of the parity bits by a length of one column group in a parity-check matrix.

An apparatus for decoding a channel in a communication system using a Low-Density Parity-Check (LDPC) code, the apparatus comprising:

• a demodulator for demodulating a signal transmitted from a transmitter;
• a puncturing pattern decision unit for determining positions of punctured parity bits by estimating information on a puncturing pattern from the demodulated signal;
• and
• a decoder for decoding data using the determined positions of the punctured parity bits,
• wherein the puncturing pattern decision unit determines the positions of the punctured bits by determining a number of punctured bits, and determining positions of punctured bits corresponding to the determined number of the punctured bits in consideration of a predetermined interval, and
• wherein the predetermined interval is determined by dividing a length of the parity bits by a length of one column group in a parity-check matrix.