认知系统中多天线协作频谱感知方案

A New Scheme for Mult-Antenna Cooperative Spectrum Sensing in Cognitive Radio Network

针对认知无线电的核心问题——频谱感知,采用性能好的协作频谱感知,这里研究了认知无线电系统中一种多天线协作频谱感知方案,此方案中的噪声信号和主用户的信号均认为是独立复高斯随机信号。同时,次用户将检测到的信号通过波束成形后传向融合中心,而优化函数为发射功率受限的条件下,最大化全局的检测概率。理论推导和方针结果表明,所提出的方案有效地提高了检查概率,充分发挥了空间分集和多用户分集的优势,普遍提高了系统的感知概率。

Aiming at the core problem in cognitive radio, the cooperative spectrum sensing with fairly good performance is adopted. This paper describes a multi-antenna cooperative spectrum sensing scheme in cognitive radios. In this scheme, the noise signal and the primary user signal are regarded as independent complex zero-mean Gaussian random signals. Meanwhile, the secondary user would report the detected signal, affter beamforming, to a fusion center, while the optimized function is the maximized global detection probability under the condition of constrained transmit power. Experiment shows that the proposed scheme could effectively raise the detection probability and the sensing probability of the system.