Interleaving scheme for an LDPC coded 16APSK system
AssigneeAvailink, Inc.
InventorsJuntan Zhang, Peng Gao, Fengwen Sun
Life of this patent
Estimating the term…
Abstract
An approach is provided for interleaving low density parity check (LDPC) encoded bits in 16ASPK modulation systems. By assigning the bits determining modulation symbols based on different bit degrees, one can efficiently find the desirable tradeoff between error performance and error floor provided by the LDPC codes in use.
Claims3
A digital communications transmitter interleaving LDPC encoded bits in a 16APSK modulation system based on a rule:
- {
- b
- ~
- i
- =
- b
- (
- 8
- ×
- ⌊
- i
- 1024
- ⌋
- +
- N
- offset
- +
- i
- 4
-
- mod
-
-
- 8
- )
- ×
- 32
- +
- ⌊
- i
- 32
- ⌋
-
- mod
-
-
- 32
- b
- ~
- i
- +
- 1
- =
- b
- (
- 8
- ×
- ⌊
- i
- 1024
- ⌋
- +
- N
- offset
- +
- i
- 4
-
- mod
-
-
- 8
- +
- 120
- )
- ×
- 32
- +
- ⌊
- i
- 32
- ⌋
-
- mod
-
-
- 32
- b
- ~
- i
- +
- 2
- =
- b
- (
- 8
- ×
- ⌊
- i
- 1024
- ⌋
- +
- N
- offset
- +
- i
- 4
-
- mod
-
-
- 8
- +
- 240
- )
- ×
- 32
- +
- ⌊
- i
- 32
- ⌋
-
- mod
-
-
- 32
- b
- ~
- i
- +
- 3
- =
- b
- (
- i
- 4
- +
- 32
- ×
- N
- offset
- +
- 11520
- )
-
- mod
-
-
- N
- ldpc_bits
- -
- (
- i
- 4
- )
-
- mod
-
-
- 256
- +
- (
- i
- 4
-
- mod
-
-
- 8
- )
- ×
- 32
- +
- ⌊
- i
- 32
- ⌋
-
- mod
-
-
- 32
- for iε{i|0≦i≦Nidpc—bits−1, and i mod 4=0}, where └x┘ is the floor function which returns the largest integer that is less than or equal to x, Nldpc—bits=15360 is the codeword length of the LDPC code in use, and NOffset is the offset values for different code rates which are defined as:
- Rate
- Noffset
- 2/3
- 80
- 3/4
- 88
- 4/5
- 96
- 5/6
- 104
- 13/15
- 112
- 9/10
- 120.
A digital communications receiver employing an LDPC decoder for decoding interleaved LDPC encoded bits in a 16APSK modulation system based on a rule:
- {
- b
- ~
- i
- =
- b
- (
- 8
- ×
- ⌊
- i
- 1024
- ⌋
- +
- N
- offset
- +
- i
- 4
-
- mod
-
-
- 8
- )
- ×
- 32
- +
- ⌊
- i
- 32
- ⌋
-
- mod
-
-
- 32
- b
- ~
- i
- +
- 1
- =
- b
- (
- 8
- ×
- ⌊
- i
- 1024
- ⌋
- +
- N
- offset
- +
- i
- 4
-
- mod
-
-
- 8
- +
- 120
- )
- ×
- 32
- +
- ⌊
- i
- 32
- ⌋
-
- mod
-
-
- 32
- b
- ~
- i
- +
- 2
- =
- b
- (
- 8
- ×
- ⌊
- i
- 1024
- ⌋
- +
- N
- offset
- +
- i
- 4
-
- mod
-
-
- 8
- +
- 240
- )
- ×
- 32
- +
- ⌊
- i
- 32
- ⌋
-
- mod
-
-
- 32
- b
- ~
- i
- +
- 3
- =
- b
- (
- i
- 4
- +
- 32
- ×
- N
- offset
- +
- 11520
- )
-
- mod
-
-
- N
- ldpc_bits
- -
- (
- i
- 4
- )
-
- mod
-
-
- 256
- +
- (
- i
- 4
-
- mod
-
-
- 8
- )
- ×
- 32
- +
- ⌊
- i
- 32
- ⌋
-
- mod
-
-
- 32
- for iε{i|0≦i≦Nldpc—bits−1, and imod 4=0}, where └x┘ is the floor function which returns the largest integer that is less than or equal to x, Nldpc—bits=15360 is the codeword length of the LDPC code in use, and NOffset is the offset values for different code rates which are defined as:
- Rate
- Noffset
- 2/3
- 80
- 3/4
- 88
- 4/5
- 96
- 5/6
- 104
- 13/15
- 112
- 9/10
- 120.
A non-transitory computer readable medium storing a computer program for performing a method specifying an interleaving scheme of LDPC encoded bits in a 16APSK modulation system base on a rule:
- {
- b
- ~
- i
- =
- b
- (
- 8
- ×
- ⌊
- i
- 1024
- ⌋
- +
- N
- offset
- +
- i
- 4
-
- mod
-
-
- 8
- )
- ×
- 32
- +
- ⌊
- i
- 32
- ⌋
-
- mod
-
-
- 32
- b
- ~
- i
- +
- 1
- =
- b
- (
- 8
- ×
- ⌊
- i
- 1024
- ⌋
- +
- N
- offset
- +
- i
- 4
-
- mod
-
-
- 8
- +
- 120
- )
- ×
- 32
- +
- ⌊
- i
- 32
- ⌋
-
- mod
-
-
- 32
- b
- ~
- i
- +
- 2
- =
- b
- (
- 8
- ×
- ⌊
- i
- 1024
- ⌋
- +
- N
- offset
- +
- i
- 4
-
- mod
-
-
- 8
- +
- 240
- )
- ×
- 32
- +
- ⌊
- i
- 32
- ⌋
-
- mod
-
-
- 32
- b
- ~
- i
- +
- 3
- =
- b
- (
- i
- 4
- +
- 32
- ×
- N
- offset
- +
- 11520
- )
-
- mod
-
-
- N
- ldpc_bits
- -
- (
- i
- 4
- )
-
- mod
-
-
- 256
- +
- (
- i
- 4
-
- mod
-
-
- 8
- )
- ×
- 32
- +
- ⌊
- i
- 32
- ⌋
-
- mod
-
-
- 32
- for iε{i|0≦i≦Nldpc—bits−1, and i mod 4=0}, where └x┘ is the floor function which returns the largest integer that is less than or equal to x, Nldpc—bits=15360 is the codeword length of the LDPC code in use, and NOffset is the offset values for different code rates which are defined as:
- Rate
- Noffset
- 2/3
- 80
- 3/4
- 88
- 4/5
- 96
- 5/6
- 104
- 13/15
- 112
- 9/10
- 120.
Dependencies are inferred from the claim text.