基于跨层优化的机会频谱接入算法

Opportunistic spectrum access algorithm based on cross-layer optimization

针对周期性信道感知机会频谱接入系统,首先采用马尔可夫过程对次用户的感知活动进行建模分析,然后结合物理层和MAC层参数提出一个跨层性能指标——有效传输容量,并在最大化有效传输容量准则下提出一种跨层优化机会频谱接入算法,进而分析了机会频谱共享系统可获得的平均有效传输容量。理论分析和仿真结果表明,所提出的跨层优化接入算法性能优于单层优化接入算法,它可以使次用户获得更高的有效传输容量。

Aiming at the opportunistic spectrum access（OSA） system with periodic channel sensing,sensing activity of secondary users was modeled and analyzed with Markov process.Combining physical layer index with MAC layer index,a cross-layer performance measure termed effective transmission capacity（ETC） was introduced.Under the criterion of maximizing ETC,a cross-layer optimal OSA algorithm was proposed and the achievable average ETC of opportunistic spectrum sharing was deduced.Theoretical analysis and simulation results indicate that the proposed algorithm is better than single-layer optimal schemes for it provides the secondary users with higher ETC.