Vehicular Ad hoc Networks (VANETs) which is a special form of Mobile Ad hoc Networks (MANETs) has promising application prospects in the future. Due to the rapid changing of topology structure, how to find a route whi...Vehicular Ad hoc Networks (VANETs) which is a special form of Mobile Ad hoc Networks (MANETs) has promising application prospects in the future. Due to the rapid changing of topology structure, how to find a route which can guarantee Quality of Service (QoS) is an important issue in VANETs. This paper presents an improved Greedy Perimeter Stateless Routing (GPSR) protocol based on our proposed next-hop node selection mechanism. Firstly, we define the link reliability in two cases which take the movement direction angle between two vehicles into consideration. Then we propose a next-hop node selection mechanism based on a weighted function which consists of link reliability between the sender node and next-hop candidate node, distance between next-hop candidate node and the destination, movement direction angle of next-hop candidate node. At last, an improved GPSR protocol is proposed based on the next-hop node selection mechanism. Simulation results are presented to evaluate the performance of the improved GPSR protocol, which shows that the performance including packet delivery ratio and average end-to-end delay of the proposed protocol is better in some situations.展开更多
K-栅栏覆盖是有向传感器网络的研究热点之一.目前为止,很少从移动和转动能耗相结合考虑有向栅栏构建.提出一种基于邻居节点运动的分布式有向强栅栏构建方法(distributed directional strong barrier construction based on neighbor act...K-栅栏覆盖是有向传感器网络的研究热点之一.目前为止,很少从移动和转动能耗相结合考虑有向栅栏构建.提出一种基于邻居节点运动的分布式有向强栅栏构建方法(distributed directional strong barrier construction based on neighbor actuation,DBCNA).在形成栅栏的节点集合中,若在前一个感知区域内部存在节点,横坐标最大的节点就是节点的目标位置.如果感知区域内部没有节点,则令前一个节点正右方向一个半径距离处作为下一节点的目标位置.有向节点的目标感知方向由移动到该位置的移动节点的初始感知方向决定.若初始感知方向0≤β≤α/2或2π-α/2≤β≤2π,目标感知方向就是节点的初始感知方向;若α/2≤β≤π,目标感知方向为β=α/2;若π<β<2π-α/2,目标感知方向为β=2π-α/2.仿真结果证明了该栅栏构建方法比其他方法节省40%的节点,平均能耗降低了40%~50%,具有重要的理论与实际意义.展开更多
文摘Vehicular Ad hoc Networks (VANETs) which is a special form of Mobile Ad hoc Networks (MANETs) has promising application prospects in the future. Due to the rapid changing of topology structure, how to find a route which can guarantee Quality of Service (QoS) is an important issue in VANETs. This paper presents an improved Greedy Perimeter Stateless Routing (GPSR) protocol based on our proposed next-hop node selection mechanism. Firstly, we define the link reliability in two cases which take the movement direction angle between two vehicles into consideration. Then we propose a next-hop node selection mechanism based on a weighted function which consists of link reliability between the sender node and next-hop candidate node, distance between next-hop candidate node and the destination, movement direction angle of next-hop candidate node. At last, an improved GPSR protocol is proposed based on the next-hop node selection mechanism. Simulation results are presented to evaluate the performance of the improved GPSR protocol, which shows that the performance including packet delivery ratio and average end-to-end delay of the proposed protocol is better in some situations.
文摘K-栅栏覆盖是有向传感器网络的研究热点之一.目前为止,很少从移动和转动能耗相结合考虑有向栅栏构建.提出一种基于邻居节点运动的分布式有向强栅栏构建方法(distributed directional strong barrier construction based on neighbor actuation,DBCNA).在形成栅栏的节点集合中,若在前一个感知区域内部存在节点,横坐标最大的节点就是节点的目标位置.如果感知区域内部没有节点,则令前一个节点正右方向一个半径距离处作为下一节点的目标位置.有向节点的目标感知方向由移动到该位置的移动节点的初始感知方向决定.若初始感知方向0≤β≤α/2或2π-α/2≤β≤2π,目标感知方向就是节点的初始感知方向;若α/2≤β≤π,目标感知方向为β=α/2;若π<β<2π-α/2,目标感知方向为β=2π-α/2.仿真结果证明了该栅栏构建方法比其他方法节省40%的节点,平均能耗降低了40%~50%,具有重要的理论与实际意义.