论文部分内容阅读
介绍了LMDS(LocalMultipointDistributionService)系统结构及系统的信道模型和前向纠错(FEC—ForwardErrorCorrection)机制。易受环境影响的LMDS系统信道特性决定了需要采用纠错能力强的纠错编码方法,在IEEE802.16工作组草案建议的MSUI(ModifiedStanfordUniversityIn-terim)信道模型下,分析了LMDS系统前向纠错采用Turbo码时的译码性能并仿真比较了RS(Reed-Solomon)码和Turbo码的误码率,同时也比较了不同Turbo码译码方法的性能。从仿真结果来看,Turbo码能够明显提高LMDS系统的前向纠错性能,可以应用到实际LMDS系统中去。
This paper introduces the architecture of LMDS (Local Multipoint Distribution Service) and the system channel model and FEC-Forward Error Correction (FEC) mechanism. The channel characteristics of LMDS system which is easily affected by the environment determine the error correction coding method which requires strong error correction capability. Based on the Modified Channel Multuniversity Channel (MSUI) model proposed by IEEE802.16 working group, the LMDS system forward error correction The decoding performance of Turbo codes is compared and the bit error rates of Reed-Solomon codes and Turbo codes are compared. The performance of different Turbo decoding methods is also compared. From the simulation results, Turbo code can significantly improve the LMDS system forward error correction performance, can be applied to the actual LMDS system.