可保持最大吞吐量的IEEE 802.11 DCF协议功率控制机制

To maintain maximum throughput IEEE 802.11 DCF protocol power control mechanism

在无线Ad Hoc网络中使用功率控制不仅可以节省能耗,还能提高网络吞吐量。基于IEEE 802.11DCF协议,提出了一种新的适用于车辆自组织网络的功率控制算法。该算法根据节点的通信状况,动态地调整接收节点的CTS帧发射功率和发送节点的数据包发射功率,进而根据使网络吞吐量达到最大时的最佳接入节点数目调节RTS帧的发射功率,从而避免冲突,增大吞吐量。仿真表明该算法不仅能降低平均能耗,延长网络生存时间,还能增大网络复用率,提高网络的平均吞吐量。

Transmission power control has been extensively used not only to save energy,but also to improve the network throughput in wireless ad hoc networks.A new adaptive power control algorithm,i.e.,PCMAC algorithm,based on IEEE 802.11 DCF protocol for Vehicular Ad hoc networks is proposed.According to the communication status,the algorithm dynamically adjusts the transmit powers of the CTS frames of receiving nodes and the data packets of the transmitting nodes,furthermore,adjusts the transmit powers of the RTS frames of the transmitting nodes according to the optimal number of access nodes such that the network throughput is maximized,in order to avoid conflicts and increase throughput.The simulation results show that the proposed PCMAC（power control media access control）algorithm can not only decrease the average energy consumption so as to prolong the lifetime of the network,but also improve spatial reuse of the wireless channel so as to improve the average throughput of the network.