中文摘要：

针对基于CSMA/CA协议的分簇传感器网络,提出了一种新的退避算法.首先通过把资源分配看成效用最大化的优化模型,说明了簇内传感器节点争用信道的退避窗口应该具有同样大小;然后在假定簇内各个节点有一样的退避窗口的基础上,通过最小化节点间的冲突概率,得到了簇内节点的最优退避窗口值和节点个数之间的关系.由此提出了一种基于最优共享退避窗口的重传算法,仿真结果表明本算法较传统的二进指数算法具有较少的冲突,能够减少传输时延、提高吞吐量,同时也是能量有效的.

英文摘要：

A novel backoff algorithm is proposed in carrier sense multiple access with collision avoidance （CSMA/CA） based medium access control （MAC） protocols for clustered sensor networks.Firstly,every node should have the same value of contention window （CW） in a cluster,when formulating resource allocation is considered as a model with maximum utility optimization.Then,it is assumed that all nodes have the same CW and gain the relation between the optimal value of CW and the number of nodes by maximizing the total network utility with constrains of minimizing collision probability.The result is a new retransmission algorithm that uses an optimal shared CW that is easy to implement and results in fewer collisions than binary exponential back off algorithm.The proposed scheme can decrease the delay to improve the throughput and save the energy in the clustered sensor networks.