基于链路保持时间的认知移动自组网拓扑算法

Topology algorithm based on link expiration time for cognitive mobile ad hoc

针对认知移动自组网中认知用户(cognitive user,CU)移动性和主用户(primary user,PU)优先通信导致网络不稳定,基于改进的移动模型,运用概率原理预测链路平均保持时间,并给出邻域拓扑保持时间的计算公式。用最大生成树的思想设计拓扑生成算法,以邻域拓扑保持时间为周期设计拓扑重构机制。证明算法保证了网络连通,同时可在各节点分布运行。仿真结果表明,算法简化了网络拓扑,对PU具有认知能力,有效减少链路断裂导致的拓扑重构和路由开销,提高了网络端到端传输效率。

Regarding the network instability of the cognitive mobile ad hoc, which is caused by the mobility of the cognitive user （CU） and the prioritized communication of the primary user （PU） , a computational formula of the neighborhood topology maintenance time is established based on the improved mobile model to forecast the average link expiration time using the principle of probability. The topology generation algorithm is designed with the thought of maximum spanning tree, and the topology reconstruction is designed with the neighborhood topology maintenance time as the cycle period. This algorithm is proved to ensure the network connection and distributed operation. The simulation result shows that this algorithm simplifies the network topology, has cognitive ability for PU, effectively decreases the topology reconfiguration and route consump tion caused by link broke and improves the end to end network efficiency.