基于卫星的流媒体应用技术研究

发布时间:2018-11-15 作者:黄泽武,韩桂鲁,李双全 阅读量:

[摘要] 带宽贵、时延大和误码率高是流媒体在卫星链路传输中亟待解决的三大问题。针对带宽贵的问题,提出将传输链路根据特点进行分段并分别采用传输控制协议(TCP)和用户数据报协议(UDP)协议,使得带宽占用与在线客户端数量无关,极大地提高卫星带宽利用率;针对时延大的问题,提出将获取流媒体的触发机制采用终端主动拉取并加入过滤机制,在协议改造前提下使得已经存在媒体流只需要解码时延而不需拉流时延,从而极大地缩减时延;针对误码高的问题,采用在流媒体源端进行冗余编码的前向纠错(FEC)方法,有效提高流媒体终端解码的成功率,从而提升流媒体应用的用户友好度。

[关键词] 卫星传输;流媒体;UDP;FEC

[Abstract] High bandwidth, high delay and high error rate are three main problems for streaming media in satellite link transmission. For the high bandwidth problem, the transmission link is segmented according to its characteristics, and the transmission control protocol (TCP) and the user datagram protocol (UDP) are adopted respectively, which makes the bandwidth occupation independent of the number of online clients and greatly improves the utilization of satellite bandwidth. The triggering mechanism of streaming media can be actively pulled by the terminal and added into the filtering mechanism. Under the premise of protocol transformation, the existing media stream only needs the decoding delay instead of the pulling delay, so that the delay can be reduced extremely. The forward error correction (FEC) method for redundant encoding at the source of streaming media is proposed, which effectively improves the success rate of streaming media terminal decoding and enhances the user-friendliness of steaming media applications.

[Keywords] satellite transmission; streaming meida; UDP; FEC

下载阅览: PDF