Apparatus and method for transmitting/receiving data in a communication system using structured low density parity check code

• US 20070011570A1
• Filed: 06/21/2006
• Published: 01/11/2007
• Est. Priority Date: 06/21/2005
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Park, Dong-Seek, Kim, Young-Kyun, Kim, Jae-Yoel, Jeong, Hong-Sil, Chae, Chan-Byoung
• Granted Patent: US 7,673,225 B2
• Time in Patent Office: Days
• US Class Current: 714/758
• CPC Class Codes: H03M 13/116 Quasi-cyclic LDPC [QC-LDPC] codes, i.e. the parity-check matrix being composed of permutation or circulant sub-matrices
• CPC Class Codes: H03M 13/31 combining coding for error detection or correction and efficient use of the spectrum without error detection or correction H03M5/14 , H03M5/145

Abstract

Provided is an apparatus and method for transmitting/receiving data in a communication system using a structured Low Density Parity Check (LDPC) code. The transmitter performs structured LDPC coding on input information data using a structured LDPC code, parallel-converts a structured LDPC codeword generated by performing the structured LDPC coding, in units of groups having a predetermined size, and transmits data. The receiver receives a plurality of parallel data streams, serial-converts the received parallel data streams in units of groups having a predetermined size, and performs structured LDPC decoding on the data which was serial-converted group by group, using a structured LDPC code.

Claims

1. A method for transmitting data in a communication system using a structured Low Density Parity Check (LDPC) code, the method comprising the steps of:

performing structured LDPC coding on input information data using a structured LDPC code; and

parallel-converting a structured LDPC codeword generated by performing the structured LDPC coding, in units of groups having a predetermined size, and transmitting data.

2. The method of claim 1, wherein the size of a group is equal to a size of a permutation matrix of a structured LDPC code.

3. The method of claim 1, further comprising performing group interleaving on the structured LDPC codeword in units of groups having a predetermined size, and parallel-converting the group-interleaved structured LDPC codeword according to the number of antennas.

4. The method of claim 3, wherein group interleaving is performed such that when codeword bits with a low degree, codeword bits belonging to a short cycle set, and codeword bits belonging to a stopping set correspond to a condition of variable nodes connected to the same check node, structured LDPC codeword bits do not use the same space-time-frequency.

5. The method of claim 1, wherein the step of performing structured LDPC coding comprises:

performing structured LDPC coding on each of at least two data streams received in parallel;

performing group interleaving on each of at least two structured LDPC codewords generated by performing the structured LDPC coding, in units of groups having a predetermined size;

performing group antenna interleaving on the group-interleaved structured LDPC codewords so as to obtain antenna diversity, and parallel-converting the structured LDPC codewords that underwent the group antenna interleaving; and

transmitting the parallel-converted structured LDPC codewords.

6. The method of claim 1, further comprising performing interleaving on each of the structured LDPC codewords which were parallel-converted group by group, using an interleaving scheme corresponding to the number of transmission antennas, and transmitting data.

7. The method of claim 1, wherein the parallel conversion step comprises parallel-converting a structured LDPC codeword according to the number of antennas.

8. The method of claim 1, wherein the data transmission step comprises transmitting data using multiple antennas.

9. A method for receiving data in a communication system using a structured Low Density Parity Check (LDPC) code, the method comprising the steps of:

receiving a plurality of parallel data streams;

serial-converting the received parallel data streams in units of groups having a predetermined size; and

performing structured LDPC decoding on the data which was serial-converted group by group, using a structured LDPC code.

10. The method of claim 9, wherein the receiving step comprises receiving a plurality of parallel data streams using multiple antennas.

11. The method of claim 9, wherein the size of a group is equal to a size of a permutation matrix of a structured LDPC code.

12. The method of claim 9, further comprising:

serial-converting the received parallel data streams;

performing group deinterleaving on the serial-converted data in units of groups having a predetermined size; and

performing structured LDPC decoding on the group-deinterleaved data.

13. The method of claim 9, further comprising detecting a signal by performing Multiple Input Multiple Output (MIMO) signal processing on the received parallel data streams, and serial-converting the detected signal in units of groups having a predetermined size.

14. The method of claim 13, wherein the signal detection step comprises detecting a signal by iterative-decoding the received signal using data that underwent the structured LDPC decoding.

15. The method of claim 13, further comprising deinterleaving the signal detected by performing the MIMO signal processing, and serial-converting the deinterleaved signal in units of groups having a predetermined size.

16. The method of claim 9, further comprising:

performing group antenna deinterleaving corresponding to a group antenna interleaving scheme of a transmitter that transmitted the data, on the received parallel data streams;

performing group deinterleaving on each of at least two parallel data streams that underwent the group antenna deinterleaving, in units of groups having a predetermined size; and

performing structured LDPC decoding on each of the group-deinterleaved parallel data streams.

17. An apparatus for transmitting data in a communication system using a structured Low Density Parity Check (LDPC) code, the apparatus comprising:

a structured LDPC encoder for performing structured LDPC coding on input information data using a structured LDPC code; and

a group serial-to-parallel (S/P) converter for parallel-converting a structured LDPC codeword generated by performing the structured LDPC coding, in units of groups having a predetermined size, and transmitting data.

18. The apparatus of claim 17, wherein the size of a group is equal to a size of a permutation matrix of a structured LDPC code.

19. The apparatus of claim 17, further comprising a group interleaver for performing group interleaving on the structured LDPC codeword of the structured LDPC encoder in units of groups having a predetermined size.

20. The apparatus of claim 19, wherein the group S/P converter parallel-converts the structured LDPC codeword group-interleaved in the group interleaver according to the number of antennas.

21. The apparatus of claim 19, wherein the group interleaver performs group interleaving such that when codeword bits with a low degree, codeword bits belonging to a short cycle set, and codeword bits belonging to a stopping set correspond to a condition of variable nodes connected to the same check node, structured LDPC codeword bits do not use the same space-time-frequency.

22. The apparatus of claim 17, further comprising at least one interleaver for performing interleaving on the structured LDPC codewords which were parallel-converted group by group, using an interleaving scheme corresponding to the number of transmission antennas, and transmitting data.

23. The apparatus of claim 17, wherein the group S/P converter parallel-converts the structured LDPC codewords according to the number of antennas.

24. The apparatus of claim 17, further comprising multiple antennas for transmitting the data.

25. The apparatus of claim 17, wherein the structured LDPC encoder includes at least two structured LDPC encoders for performing structured LDPC coding on each of parallel input data streams.

26. The apparatus of claim 25, further comprising:

at least two group interleavers for performing group interleaving on each of the structured LDPC codewords output from the structured LDPC encoders in units of groups having a predetermined size; and

a group antenna interleaver for performing group antenna interleaving on the structured LDPC codewords group-interleaved by the group interleavers so as to acquire antenna diversity, and parallel-converting the structured LDPC codewords that underwent the group antenna interleaving.

27. The apparatus of claim 26, wherein the group antenna interleaver parallel-converts the structured LDPC codewords according to the number of antennas.

28. An apparatus for receiving data in a communication system using a structured Low Density Parity Check (LDPC) code, the apparatus comprising:

a parallel-to-serial (P/S) converter for receiving a plurality of parallel data streams, and serial-converting the received parallel data streams in units of groups having a predetermined size; and

a structured LDPC decoder for performing structured LDPC decoding on the data which was serial-converted group by group, using a structured LDPC code.

29. The apparatus of claim 28, further comprising multiple antennas for receiving the data.

30. The apparatus of claim 28, wherein the size of a group is equal to a size of a permutation matrix of a structured LDPC code.

31. The apparatus of claim 28, further comprising a group deinterleaver for performing group deinterleaving on the serial-converted data output from the P/S converter in units of groups having a predetermined size, and outputting group-deinterleaved data to the structured LDPC decoder.

32. The apparatus of claim 28, further comprising a Multiple Input Multiple Output (MIMO) signal processor for detecting a signal by performing MIMO signal processing on the received parallel data streams, and outputting the detected signal to the group P/S converter.

33. The apparatus of claim 32, wherein the MIMO signal processor performs iterative decoding from the received parallel signal using the output signal of the structured LDPC decoder.

34. The apparatus of claim 32, further comprising a deinterleaver for deinterleaving the signal detected in the MIMO signal processor, and outputting the deinterleaved signal to the group P/S converter.

35. The apparatus of claim 28, further comprising:

a group antenna deinterleaver for performing group antenna deinterleaving corresponding to a group antenna interleaving scheme of a transmitter that transmitted the data, on the received parallel data streams;

at least two group deinterleavers for performing group deinterleaving on each of the parallel data streams that underwent the group antenna deinterleaving, in units of groups having a predetermined size; and

at least two structured LDPC decoder for performing structured LDPC decoding on each of the parallel data streams that underwent the group deinterleaving in the group deinterleavers.