Two-Extra-Column Trellis Min–Max Decoder Architecture for Nonbinary LDPC Codes

In this brief, a novel two-extra-column trellis min-max algorithm and the decoder architecture based on only the first minimum values are proposed for nonbinary low-density parity-check (NB-LDPC) codes. The algorithm greatly reduces the hardware complexity and improves the latency as well as the throughput of the proposed decoder architecture compared with the previous works. A layered decoder architecture based on the proposed algorithm for (837, 726) NB-LDPC code over GF(32) is implemented with a 90-nm CMOS technology. The results show a decrease in the area of 24.6% for the check node unit and 75.6% for the whole decoder with a throughput of 1.27 Gb/s. The proposed decoder provides a lower area and a higher efficiency compared with the state of the art of high-rate NB-LDPC codes with high Galois-field order.