Partial Parallel Encoding and Algorithmic Construction of Non-Binary Structured IRA Codes  

作　　者：Wojciech Sulek Marcin Kucharczyk 

机构地区：[1]Faculty of Automatic Control, Electronics and Computer Science, Silesian University of Technology

出　　处：《China Communications》2016年第8期103-116,共14页中国通信（英文版）

基　　金：supported by the Polish Ministry of Science and Higher Education funding for statutory activities (decision no. 8686/E-367/S/2015 of 19 February 2015)

摘　　要：The non-binary(NB) Irregular Repeat Accumulate(IRA) codes, as a subclass of NB LDPC codes, potentially have an excellent error-correcting performance. They are also known to provide linear complexity of encoding, but the basic encoding method with the serial rate-1 accumulator significantly limits the encoder throughput. Then the objective of the research presented in this paper is to develop an encoding method pro- viding significantly increased throughput of an NB-IRA encoder altogether with a flexible code construction methods for the structured(S-NB-IRA) codes eligible for the proposed encoding method. For this purpose, we reformulate the classic encoding algorithm to fit into the partial parallel encoder architecture. We propose the S-NB-IRA encoder block diagram and show that its estimated throughput is proportional to the submatrix size of the parity check matrix, which guarantees a wide complexity- throughput tradeoff. Then, in order to facilitate the S-NB-IRA coding systems design, we present a computer search algorithm for the construction of good S-NB-IRA codes. The algorithm aims at optimizing the code graph topology along with selecting an appropriate non-binary elements in the parity check matrix. Numerical results show that the constructed S-NB-IRA codes significantly outperform the binary IRA and S-IRA codes, while their performance is similar to the best unstructured NB-LDPC codes.The non-binary （NB） Irregular Repeat Accumulate （IRA） codes, as a subclass of NB LDPC codes, potentially have an excellent er- ror-correcting performance. They are also known to provide linear complexity of encoding, but the basic encoding method with the serial rate- 1 accumulator significantly limits the encoder throughput. Then the objective of the research presented in this paper is to develop an encod- ing method pro- viding significantly increased throughput of an NB-IRA encoder altogether with a flexible code construction methods for the struc- tured （S-NB-IRA） codes eligible for the proposed encoding method. For this purpose, we reformu- late the classic encoding algorithm to fit into the partial parallel encoder architecture. We propose the S-NB-IRA encoder block diagram and show that its estimated throughput is proportional to the submatrix size of the parity check matrix, which guarantees a wide complexity- throughput tradeoff. Then, in order to facilitate the S-NB-IRA coding systems design, we present a computer search algorithm for the construction of good S-NB-IRA codes. The algorithm aims at optimiz- ing the code graph topology along with selecting an appropriate non-binary elements in the parity check matrix. Numerical results show that the constructed S-NB-IRA codes significantly outper- form the binary IRA and S-IRA codes, while their performance is similar to the best unstructured NB-LDPC codes.

关 键 词：channel coding LDPC codes non-binary LDPC IRA codes LDPC encoding LDPC encoder design 

分 类 号：TN911.22[电子电信—通信与信息系统]