Method and apparatus for weighted non-binary repeat accumulate coding and space-time coding

• US 7,423,996 B2
• Filed: 01/16/2003
• Issued: 09/09/2008
• Est. Priority Date: 01/16/2002
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Kim, Jae-Yoel, Son, Jungmin, Yang, Kyeongchul
• Primary Examiner(s): Nguyen; Chau T.
• Assistant Examiner(s): SMITH, MARCUS
• Application Number:
  US10/345,556
• Publication Number:
  US 20030235166A1
• Time in Patent Office: 2,063 Days
• Field of Search: 370/342, 714/786
• US Class Current: 370/335
• CPC Class Codes: H03M 13/1171 Parity-check or generator matrices with non-binary elements, e.g. for non-binary LDPC codes
• CPC Class Codes: H03M 13/1194 Repeat-accumulate [RA] codes
• CPC Class Codes: H03M 13/23 using convolutional codes, e.g. unit memory codes
• CPC Class Codes: H03M 13/25 Error detection or forward error correction by signal space coding, i.e. adding redundancy in the signal constellation, e.g. Trellis Coded Modulation [TCM] modulation codes H03M13/31
• CPC Class Codes: H03M 13/29 combining two or more codes or code structures, e.g. product codes, generalised product codes, concatenated codes, inner and outer codes
• CPC Class Codes: H04L 1/0618 Space-time coding
• CPC Class Codes: H04L 1/08 by repeating transmission, e.g. Verdan system H04L1/1858 and H04L1/189 take precedence

Abstract

An apparatus and method for weighted non-binary RA coding and space-time coding are disclosed. Transmission data is divided in the units of frames each having mN bits, and each frame is further segmented into N blocks, each block containing m bits. The N blocks are converted to N non-binary GF(2^m) elements. These N non-binary symbols are repeated by a repetition factor r. The rN symbols are multiplied by weighting factors being GF(2^m) elements other than zero. The rN weighted symbols are interleaved and accumulated. The rN accumulated symbols are transmitted to a receiver, or each of the rN accumulated symbols is demapped to m bits prior to transmission. Therefore, information can be transmitted reliably in a wireless communication system.

Claims

1. A mobile communication system using multiple antennas comprising:

a repeater for receiving non-binary symbols and repeating the non-binary symbols;

a weighter for weighting the repeated non-binary symbols by multiplying the identical repeated non-binary symbols by corresponding different weighting factors;

an interleaver for interleaving the weighted non-binary symbols; and

a coder for coding the interleaved symbols;

wherein a plurality of binary bits are represented by the non-binary symbol, the repeater repeats the symbols by a repetition factor determined by a data rate of the communication system and a number of the antennas, and a number of the corresponding different weighting factors is equal to the repetition factor.

2. The mobile communication system of claim 1, further comprising a mapper for mapping the plurality of binary bits to a non-binary element over a Galois Field, GF2^m, where m is the number of binary bits mapped to the non-binary element.

3. The mobile communication system of claim 2, wherein the weighter has the non-binary elements over a Galois Field, GF2^m as the weighting factors.

4. The mobile communication system of claim 3, wherein the weighter has a number of weighting factors equal to a number of the repeated operation of the repeater and multiply the same repeated symbols by the different weighting factors.

5. The mobile communication system of claim 1, wherein the coder comprises an accumulator.

6. The mobile communication system of claim 1, wherein the coder comprises an Recursive Systematic Convolutional (RSC) code.

7. The mobile communication system of claim 5, wherein the coder comprises an accumulator for receiving the non-binary symbols from the interleaver and sequentially accumulating the non-binary symbols.

8. The mobile communication system of claim 6, wherein the coder comprises an 1-tap Recursive Systematic Convolutional(RSC) code.

9. The mobile communication system of claim 1, further comprising a demapper for mapping the coded non-binary symbols to the plurality of binary bits.

10. The mobile communication system of claim 9, further comprising a signal mapper for assigning the plurality of binary symbols received from the demapper to antennas respectively.

11. A coding method for use in a mobile communication system using multiple antennas, the method comprising the steps of:

receiving non-binary symbols and repeating the non-binary symbols;

weighting the identical repeated non-binary symbols by multiplying the repeated non-binary symbols by corresponding different weighting factors;

interleaving the weighted non-binary symbols; and

coding the interleaved symbols,

wherein a plurality of binary bits are represented by a non-binary symbol, the symbols are repeated by a repetition factor determined by a data rate of the communication system and a number of the antennas, and a number of the corresponding different weighting factors is equal to the repetition factor.

12. The method as claimed in claim 11, further comprising the step of mapping the plurality of binary bits to a non-binary element over a Galois Field, GF2^m, wherein m is the number of binary bits mapped to the non-binary element.

13. The method as claimed in claim 12, wherein the weighting factors are the non-binary elements over a Galois Field, GF2^m.

14. The method as claimed in claim 11, wherein a number of weighting factors are equal to a number of the repeating operation and the same repeated symbols are multiplied by the different weighting factors.

15. The method as claimed in claim 11, wherein the coding is performed by Recursive Systematic Convolutional (RSC) coding, the interleaved non-binary symbols.

16. The method as claimed in claim 11, wherein the coding is performed by sequentially accumulating the interleaved non-binary symbols.

17. The method as claimed in claim 15, wherein the RSC coding is 1-tap RSC coding.

18. The method as claimed in claim 11, further comprising demapping the coded non-binary symbols to the plurality of binary bits.

19. The method as claimed in claim 18, further comprising assigning the plurality of binary symbols to antennas respectively.

20. The method as claimed in claim 14, wherein the weighting factors are GF2^m elements other than zero in the weighting step.

21. A mobile communication system using multiple antennas comprising:

a repeater for receiving symbols and repeating the symbols;

a weighter for weighting the repeated symbols by multiplying the identical repeated symbols by corresponding different weighting factors;

an interleaver for interleaving the weighted symbols; and

a coder for coding the interleaved symbols,

wherein a plurality of binary bits are represented by a non-binary symbol, the repeater repeats the symbols by a repetition factor determined by a data rate of the communication system and a number of the antennas, and a number of the corresponding different weighting factors is equal to the repetition factor,

wherein the mobile communication system further comprises a mapper for mapping the plurality of binary bits to the non-binary element over a Galois Field, GF2^m, where m is the number of binary bits mapped to the non-binary element, and a demapper for mapping the encoded non-binary symbols to the plurality of binary bits.

22. The mobile communication system of claim 21, wherein the weighter has the non-binary elements over a Galois Field, GF2^m as the weighting factors.

23. The mobile communication system of claim 22, wherein the weighter has a number of weighting factors equal to a number of the repetition and multiply the same repeated symbols by the different weighting factors.

24. The mobile communication system of claim 21, wherein the coder comprises an accumulator.

25. The mobile communication system of claim 21, wherein the coder comprises an Recursive Systematic Convolutional (RSC) code.

26. The mobile communication system of claim 24, wherein the coder comprises an accumulator for receiving the non-binary symbols from the interleaver and sequentially accumulating the non-binary symbols.

27. The mobile communication system of claim 21, wherein the coder comprises an 1 tap Recursive Systematic Convolutional (RSC) code.

28. The mobile communication system of claim 27, further comprising a signal mapper for assigning the plurality of binary symbols received from the demapper to antennas respectively.

29. A method for use in a mobile communication system using multiple antennas, the method comprising the steps of:

receiving symbols and repeating the symbols;

weighting the identical repeated symbols by multiplying the repeated symbols by corresponding different weighting factors;

interleaving the weighted symbols; and

coding the interleaved symbols,

wherein a plurality of binary bits are represented by a non-binary symbol, the symbols are repeated by a repetition factor determined by a data rate of the communication system and a number of the antennas, and a number of the corresponding different weighting factors is equal to the repetition factor,

wherein the method further comprises the steps of;

mapping the plurality of binary bits to a non-binary element over a Galois Field, GF2^m, wherein m is the number of binary bits mapped to the non-binary element; and

demapping the encoded non-binary symbols to the plurality of binary bits.

30. The method as claimed in claim 29, wherein the weighting factors are the non-binary elements over a Galois Field, GF2^m.

31. The method as claimed in claim 29, wherein a number of weighting factors are equal to a number of the repetition and the same repeated symbols are multiplied by the different weighting factors.

32. The method as claimed in claim 29, wherein the coding is performed by Recursive Systematic Convolutional(RSC) coding, the interleaved non-binary symbols.

33. The method as claimed in claim 29, wherein the coding is performed by sequentially accumulating the interleaved non-binary symbols.

34. The method as claimed in claim 32, wherein the RSC coding is a 1 tap RSC coding.

35. The method as claimed in claim 29, further comprising the step of assigning the plurality of binary symbols to antennas respectively.

36. The coding method of claim 31, wherein the weighting factors are GF2^m elements other than zero in the weighting step.