车载自组网功率自适应调整算法建模与仿真

Modeling and Simulation of Power Self- Adaptive Algorithm for Vehicular Ad-Hoc Networks

当车载自组网(Vehicular Ad-hoc NETworks,VANET)拥有较高的节点密度时,较高的传输功率会导致严重的信道拥塞,降低信宿车辆的分组接收概率;当网络较为稀疏时,过高的传输功率并不能显著提升分组接收概率,同时造成不必要的成本开销.针对上述问题,建立了一种基于功率自适应调整模型,并在此模型基础上构建了PSA(Power-based Self-adaptive Algorithm,PSA)算法.该模型通过感知网络通信密度自动调整发送功率,在提高信宿节点分组接收概率的基础上节约自身的能源开销.仿真结果表明:网络节点密度较高时,发送节点能够以较小的发送功率使接收节点获得最大的分组接收概率;网络节点密度较小时,发送节点能以较小的发送功率使接收节点获得相对令人满意的分组接收概率.

When VANET（Vehicular Ad-hoc NETworks）has high node density,higher transmission power could lead to severe channel congestion and reduce the packets reception rate of receiving vehicle nodes.When the network is sparse,high transmission power could not significantly improve the packets reception rate and causes unnecessary overhead.In view of issues above,a model based on power self-adaptation is proposed,and PSA（Power-based Self-a-daptive Algorithm）is established.This model can automatically adjust the transmission power by sensing communica-tion density,and meet the requirements of increasing the packets reception rate of receiving nodes and of saving energy of transmitting nodes.Simulation results indicate that transmitting nodes can maximize the reception rate of receiving nodes by using low transmission power when the network has high nodes density and when the network is sparse, the low transmission power can also result in acceptable packets reception rate of receiving nodes.