一种适合实时视频传输的混合ARQ加条件跳帧算法研究

A Novel Hybrid ARQ with Conditional Frames Skipped Algorithm for Real-Time Video Transmission

论文讨论视频数据在无线局域网(WLAN)中的实时传输问题。采用IEEE802.11b协议,WLAN可提供高达11Mbps的传输速率,在没有干扰和没有拥塞的情况下,其环境完全满足实时视频传输的需要。但在干扰和拥塞严重的情况下,视频帧的延时很大,无法满足实时播放的要求。文献犤1犦提出了一种混合ARQ算法,可较好地解决视频帧的传输延迟问题,但在网络负载很重时,丢包率很高,视频序列的重构质量很差。因而在深入研究IEEE802.11b协议的核心MAC层的基础上,参考文献犤1犦,提出了一种新的适合实时视频传输的混合ARQ算法,结合高层的基于反馈信息的条件跳帧技术,可很好地解决视频帧的延时问题,同时传输的可靠性也很高。

Real-time video transmission over WLAN has been studied in this article.Based on IEEE802.11b,the data rate of WLAN is up to11Mbps that can entirely meet the requirement for real-time video transmission when the net-work isn't congested.But the delay is too high to transmit the real-time video in the case of severe congestion.A novel hybrid ARQ scheme ,which has been proved effective in low delay,has been proposed in reference1.But when the net-work load is very heavy,the packet loss rate is high which lead to poor quality of reconstructed video sequence.In this paper,we proposed a novel hybrid ARQ with conditional frames skipped algorithm based on the feedback from the re-ceiver.The algorithm has been proved effective both in the delay and the perceived picture quality.