摘要
脉冲超宽带系统通过发送宽度极窄的脉冲进行通信,因没有载波调制,所以基于载波侦听方式的MAC协议不适用于IR-UWB系统.针对常用的UWB MACAW MAC协议在网络负荷较大时RTS/CTS握手失败概率大的问题,提出了一种先由接收节点传送FI帧指示其处于空闲状态,然后发送节点再进行握手的UWB-RI MAC协议,以增大握手成功的概率.通过给出的UWB-RIMAC协议数据收发的详细流程,分析了FI帧广播间隔的取值,说明其对QoS的支持;最后仿真比较了UWB-RI MAC和UWB MACAW MAC的性能.
An IR-UWB system communicates by transmitting very narrow pulses. Without use of carrier modulation, MAC protocol based on carrier sensing can not be applied to IR-UWB system. Through analyzing the cause of RTS/CTS handshake failure of UWB MACAW MAC, UWB-RI MAC with receiver controlled handshake was proposed. In UWB-RI MAC, the receiver sends FI frame to indicate that it is free to receive RTS, and then the sender transmits RTS to start RTS/CTS handshake. Based on detailed working process of UWB-RI MAC, FI frame broadcast interval was analyzed and the support for QoS was explained. Finally, the performance simulation and comparison of UWB-RI MAC and UWB MACAW MAC were given.
基金
国家自然科学基金重大项目(60496314)
中科院国防科技创新基金(CXJJ-127)资助
