中文摘要：

研究了多跳分集系统中由于链路的不可靠传输直接应用实用网络编码存在差错的扩散和传播问题。提出了一种新的基于无比率编码的跨层方案,该方案利用无比率编码的纠错能力及实用网络编码码字随机特性,控制了输入链路的差错扩散和传播。结果表明,在满足每条链路误包率一定的情况下,该方案获得了较好的差错性能。进一步分析了为了使每条链路达到给定的误包率,无比率编码在不同信噪比下的冗余。

英文摘要：

The influence of error propagation caused by practical network coding in multihop diversity systems is studied when the links are unreliable. The cross - layer design based on rateless codes is proposed, which uti- lizes the error correction of rateless codes and random characteristic of practical network coding to control the er- ror propagation. Simulation results show that the proposed scheme has lower packet error rate, compared with a single channel. To achieve the predefined packet error rate of a single channel, the redundancy of the rateless codes is also analysed under different signal - to - noise - ratio conditions.