A 26.9 K 314.5 Mb/s Soft (32400,32208) BCH Decoder Chip for DVB-S2 System

Yi-Min Lin, Chih-Lung Chen, Hsie-Chia Chang, Chen-Yi Lee
2010 IEEE Journal of Solid-State Circuits  
This paper provides a soft Bose-Chaudhuri-Hochquenghem (BCH) decoder chip with soft information from the LDPC decoder for the DVB-S2 system. In contrast with the hard BCH decoder, the proposed soft BCH decoder that deals with least reliable bits can provide much lower complexity with similar error-correcting performance. Moreover, the error locator evaluator is proposed to evaluate error locations without the Chien search for higher throughput, and the Björck-Pereyra error magnitude solver
more » ... MS) is presented to improve decoding efficiency and hardware complexity. The chip measurement results reveal that our proposed soft (32400, 32208) BCH decoder for DVB-S2 system can achieve 314.5 Mb/s with a gate-count of 26.9 K in standard 90 nm 1P9M CMOS technology. Extended for fully supporting 21 modes in the DVB-S2 system, our approach can achieve 300 MHz operation frequency with a gate-count of 32.4 K. Index Terms-Bose-Chaudhuri-Hochquenghem (BCH) codes, digital video broadcasting, DVB-S2, error-correction coding. I. INTRODUCTION T HE Bose-Chaudhuri-Hocquenghen (BCH) codes are cyclic codes which operate under Galois Field [1]. With similar code rate and codeword length, additional 0.6 dB coding gain is observed for BCH codes as compared with error-only decoding RS codes [2]. Hence, BCH codes with different block lengths, ranging from short ( 100 b) to extremely long ( 60 Kb), are very popular in storage and communication systems, such as DMB-T [3], DVB-T2 [4], and DVB-S2 [5] broadcasting systems. The DVB-S2 system shown in Fig. 1 is the second-generation standard of digital video broadcasting via satellites, which was developed by the European Telecommunications Standard Institute (ETSI). It provides higher order modulations and a powerful FEC system based on serial concatenation of BCH codes and low-density parity check (LDPC) codes, leading to 30% channel capacity gain over the existing DVB-S standard [6] . For the high-speed and long-distance data transmission, the BCH codes with long block length are specified to suppress the error floor due to iterative LDPC decoding. The BCH codes have 21 different code rates, where there are for DVB-S2 normal frame and for DVB-S2 short frame. Three kinds of Manuscript
doi:10.1109/jssc.2010.2065630 fatcat:oqcogags6nbw5iohdru3a6wvrm