基于最优停止的认知无线网络下行频谱接入算法

Downlink Spectrum Access Algorithm Based on Optimal Stopping Theory in Cognitive Radio Networks

为有效平衡认知无线网络中次用户系统中接入信道的感知时间和信道总的吞吐量之间的矛盾，提出了一种只对部分信道进行感知的频谱接入策略，联合总的感知信道数和各条信道的感知时间进行优化，并通过最优停止算法求解，在最大化节省感知时间的同时，取得较大的平均吞吐量。与HC-MAC（ Hardware Constrained- Media Access Control）算法的仿真分析对比表明，该算法在相同给定条件下感知时间更短，吞吐量更大，具有明显的优势。

To effectively balance the contradiction between the access channels sensed time and total channel throughput in cognitive radio secondary user network system,this paper proposes a spectrum access strategy which only senses partial channel channels. The strategy optimizes the total number of sensing channels and sensing time of individual channels jointly, and solves the result through optimal stopping algorithm. The al-gorithm can maximize savings while achieving larger average throughput in the sensed time. The simulation analysis and comparison with HC-MAC（ Hardware Constrained-Media Access Control） algorithm show that the algorithm costs shorter sensed time and has greater throughput in the same given conditions.