Split-Row: A Reduced Complexity, High Throughput LDPC Decoder Architecture

A reduced complexity LDPC decoding method is presented that dramatically reduces wire interconnect complexity, which is a major issue in LDPC decoders. The proposed split-row method makes column processing parallelism easier to exploit, doubles available row processor parallelism, and significantly simplifies row processors - which results in smaller area, higher speeds, and lower energy dissipation. Simulation results over an additive white Gaussian channel show that the error performance of high row-weight codes with split-row decoding is within 0.3-0.6 dB of the min-sum and sum-product decoding algorithms. A full parallel decoder for a (3,6) LDPC code with a code length of 1536 bits is implemented in a 0.18 mum CMOS technology twice: once using the split-row method, and once using the min-sum algorithm for comparison. The split-row decoder operates at 53 MHz and delivers a throughput of 5.4 Gbps with 15 decoding iterations per block. The split-row decoder is about 1.3 times smaller, has an average wire length 1.5 times shorter, and has a throughput 1.6 times higher than the min-sum decoder.