| Reed-Solomon(RS)codes are a class of error control codes that are used in optical communication system.From 40Gb/s to 100Gb/s and even 400Gb/s,higher-rate optical transmission technology is the inexorable trend for the development of era.In order to design a forward error correction decoding algorithm which can be applied to high-speed optical communication system,we optimized the most advanced Hard-Decision Decoding(HDD)algorithm,Compensated Simplified Reformulated inversionless Berlekamp-Massey(CS-RiBM)algorithm,and proposed the modified CS-RiBM(mCS-RiBM)algorithm.The new initial value was applied to reduce iteration time,and the redundant processing element was removed by analyzing the intrinsic relationship between inputs and outputs of the original CS-RiBM algorithm.Finally,the iteration time is reduced to 2t-1,and the processing element number is reduced to 2t + 1.In addition,two 16-channel forward error correcting decoders for RS(255,239)codes were designed for 100Gb/s and even higher speed optical communication system based on the mCS-RiBM algorithm.The Syndrome Calculation(SC)block and Chien Search & Error Evaluation(CSEE)block adopted the parallel structure to shorten the execution time difference between them and the Key Equation Solver(KES)block.Besides,the KES block of 16-channel two-parallel architecture applied the folding technology,which could reduce the circuit area and the idle time,and significantly improve the area and time utilization of the decoder.The two proposed architectures have been modeled by Verilog HDL hardware description language,and synthesized with Synopsys design tools Design Compiler based on TSMC 90 nm CMOS technology library.Synthesis results illustrate that,compared with the existing technologies,the 16-channel four-parallel architecture designed can achieve 321Gb/s throughput at the cost of small increase in area,while the 16-channel two-parallel architecture can achieve 162Gb/s throughput on the premise of maintaining the hardware area advantage.Meawhile,the two architectures designed have high efficiency,which is improved by 9% to 44% compared with other technologies,and can meet the needs of high-speed optical communication system. |
