【摘要】 无线传感器网络(Wireless Sensor Network,WSN)传输实时媒体面临带宽受限,时变和高误码等信道特征的挑战,常采用自适应速率控制技术并结合链路层重传机制,但增大了传输时延.本文采用IEEE802.11构建WSN,分析引发链路层重传的原因,推导满足重传时延最小的传输层包长调整方程和结合TFRC(TCP Friendly Rate Control)建立WSN实时媒体传输的速率控制机制(WSN Rate Control,WSNRC).仿真结果表明,该机制能有效改善降低丢包率(Packet Loss Rate,PLR),实时媒体帧平均传输时延和帧时延抖动等指标和具备传感器节点间的公平特征.更多还原

【Abstract】 To address the challenge of transmitting realtime media in Wireless Sensor Network (WSN) due to the fluencies of bandwidth limitation,variation and high error rate,and so on,adaptive rate control scheme is usually applied associating with retransmission mechanism in link layer.However,it will increase transmission delay.In this paper,WSN is constructed by IEEE802.11.An equation of transport layer packet size adjustment is deduced to minimize retransmission delay with focus on the reasons which induce retransmission in link layer.Finally,a WSN Rate Control (WSNRC) scheme is proposed integrating with TFRC (TCP Friendly Rate Control).Simulation results demonstrate that lower Packet Loss Rate (PLR),and lower frame delay and jitter with good fairness among sensor nodes can be achieved by our proposed mechanism.更多还原