基于TURBO码和分块传输的新型HARQ系统

Novel Turbo HARQ system based on sub-packet transmission

本文采用TURBO码为纠错码,在分析传统的反馈重传方式的基础上,将分块传输系统和码合并技术相结合,提出了一种新型HARQ系统,并为其设计了新型交织器。新型HARQ系统将每帧数据多次重传合并,转化为在一帧的多个分块之间合并,不需要重传。该系统大幅度降低了重传次数、交织的时延和平均迭代次数,实现了数据的实时通信;译码器接收的数据在解扩之前充分合并,更加有效地利用了软信息;该系统还省去了常用I型HARQ系统中必须使用的收发端复杂的反馈重传控制和庞大的存储器;新型HARQ系统中TURBO码的最小距离增加为原来的许多倍。通过理论分析和仿真比较了新型HARQ系统和I型HARQ系统的性能,结果证明了新型HARQ系统性能的优越性。新型HARQ系统为第三代无线通信技术提供了一种较好地选择。

A new HARQ system based on TURBO code is proposed in the paper by combining the sub-packet transmission scheme with the averaged diversity combining technique. A new interleaver is designed for the new HARQ system. In the new HARQ system the diversity combining of a data packet and its copy in the retransmissions is converted to the diversity combining of the identical sub-packets in one data packet without retransmissions. The delay for retransmission, interleaving and the average iteration times are decreased greatly in the new HARQ system to guarantee the real time communication. The received sequences are combined before the despread to make the decoder using the soft information efficiently. In addition the new HARQ system has omitted the complicated retransmission control scheme and a mass of memory. The minimum distance of the new HARQ system is times of the minimum distance of the type-Ⅰ HARQ. Numerical and simulation results prove the great advantage of the new HARQ system, New HARQ system provides an alteration for 3GPP.