A 11.5-Gbps LDPC decoder based on CP-PEG code construction

In this paper, a LDPC decoder chip based on CPPEG code construction is presented. The (2048, 1920) irregular LDPC code generated by CP-PEG algorithm has better performance than other PEG-based codes; however, the large check node degrees introduced by high code-rate 15/16 become the implementation bottleneck. To design such a high code-rate LDPC decoder, our approach features variable-node-centric sequential scheduling to reduce iteration number, single piplelined decoder architecture to lessen the message storage memory size, as well as optimized check node unit to further compress the register number. Overall 73% message storage memory is saved as compared with traditional architecture. Fabricated in 90 nm 1P9M CMOS technology, a test decoder chip could achieve maximum 11.5 Gbps throughput under 1.4 V supply voltage with core area of 2.7 times 1.4 mm². The energy efficiency is only 0.033 nJ/bit with 5.77 Gbps at 0.8 V to meet IEEE 802.15.3c requirements.