一种单向卫星网络中冗余递增的数据分发机制

Incremental Redundancy-based Data Distribution Scheme over Unidirectional Satellite Networks

为了解决单向数据分发系统存在的问题,设计了一种新的数据分发机制。一方面,分组级FEC机制被用来恢复接收端的误码。另一方面,发送端采用冗余递增的方式发送分组级FEC编码生成冗余信息。发送端将冗余信息分层传输,接收端通过加入一个或多个发送层次以接收不同冗余度的数据,从而有效地解决了接收端异质性引起的系统效率降低。仿真结果表明,新的数据分发机制可以使误码率低的接收端尽快接收到需要的数据,在保证数据可靠传输的同时提高了系统的发送效率。

Due to heterogenous receivers in unidirectional satellite network, traditional data distribution scheme can not work well. To solve this problem, an Incremental Redundancy Based data distribution scheme is proposed. In this scheme, Packet-level FEC （PLFEC） and layered transmission is adopted. First, PLFEC is adopted to recov- er losses. Second, Redundancy data produced by PLFEC is classified according to receivers＇ package loss rate. Then layered transmission scheme is used to send redundancy data of each classification in turn. Thus receivers can get redundancy packages as they need by joining one or more transmission layers. System efficiency would not be affected by high loss rate receivers. Analysis and simulations results show that by using this scheme receivers can get redundancy data soon and system efficiency is significant promoted.