Strength-Reduced Parallel Chien Search Architecture for Strong BCH Codes

Abstract

The Chien search process is the most complex block in the decoding of Bose-Chaudhuri-Hochquenghem (BCH) codes. Since the BCH codes conduct the bit-by-bit error correction, they often need a parallel implementation for high throughput applications. The parallel implementation obviously needs much increased hardware. In this paper, we propose a strength reduced architecture for the parallel Chien search process. The proposed method transforms the expensive modulo-f(x) multiplications into shift operations, by which not only the hardware for multiplications but also that for additions are much reduced. One example shows that the hardware complexity is reduced by 90% in the implementation of binary BCH (8191, 7684, 39) code with the parallel factor of 64. Consequently, it is possible to achieve a speedup of 64 with only 13 times of the hardware complexity when compared with the serial processing.