High Performance LDPC Decoder on CELL BE for WiMAX System

Low-density parity-check (LDPC) codes are widely used in many radio systems due to its superior performance and Software Defined Radio (SDR) is an emerging paradigm of the wireless communication system design due to its good flexibility and adaptability. However, LDPC decoding is computationally intensive and the implementation of it on software in a parallel way is quite challenging due to the characteristics of LDPC decoding and structures of software. In this paper, we presented an efficient software implementation of the LDPC decoder using the Parallel Code Block Decoding mode for the WiMAX SDR base band system on IBM CELL Broadband Engine (BE). With a single Synergistic Processor Element (SPE) running at 3.2GHz, the implemented LDPC decoder can achieve a throughput up to 1.71 Mbps. With eight SPEs working in parallel, the decoder can obtain the throughput more than 13Mbps, which can meet the WiMAX system requirement at 5MHz bandwidth mode.