DCF传输MPEG-4视频流的研究  

Study on Transmitting MPEG-4 Video Stream in WLAN

作　　者：邹仕洪[1] 林华生[1] 程时端[1] 

机构地区：[1]北京邮电大学交换技术与通信网国家重点实验室,北京100876

出　　处：《电子与信息学报》2005年第1期131-135,共5页Journal of Electronics & Information Technology

基　　金：国家自然科学基金(90204003)高等学校博士学科点专项科研基金(20010013003)资助课题

摘　　要：IEEE 802.11无线局域网的基本接入方式是分布式协调功能(DCF)。当无线局域网中的负载变大时,采用DCF的站点可能在成功发送之前需要延迟几秒以上。这将严重影响MPEG-4视频流等实时应用的性能。该文针对实时应用提出了一种DCF的改进机制L-DCF,并介绍了在L-DCF下如何传输MPEG-4视频流。仿真结果表明,与DCF相比,采用L-DCF的MPEG-4视频流将经历较少的时延和抖动,同时又具有与采用DCF时相同的吞吐量与公平性,因此能够获得更好的播放质量。The basis of IEEE 802.11 wireless LAN Medium Access Control (MAC) is Distributed Coordination Function (DCF). When network load in WLAN is moderate or even higher, with DCF a station may need to defer several seconds before successful transmission. This will degrade the performance of real time applications such as MPEG-4 video stream. This paper proposes L-DCF, which is suit for real time applications, and presents mechanism for transmitting MPEG-4 video stream with L-DCF. Simulations show that this mechanism provides much less delay and jitter while obtains the same goodput and fairness.

关 键 词：无线局域网 IEEE802.11 分布式协调功能 MPEG-4 

分 类 号：TP393.1[自动化与计算机技术—计算机应用技术]