一种基于小区内次用户间协作的频谱检测策略

A spectrum sensing strategy based on cooperation among intra-cell secondary users

认知无线电中频谱检测性能直接影响频谱资源的使用效率,考虑次用户在空间的随机分布特性,本文提出了一种基于小区内次用户协作的频谱检测策略以提高检测性能。该策略将空间划分为若干个协作小区,同一小区内的次用户进行协作检测从而获得协作增益。基于漏警概率和虚警概率的理论推导分析可知,该策略的检测性能主要取决于协作小区的半径和检测判决门限的设置,并由此给出这两个参数设置的方法;分析还表明次用户在空间分布的随机性降低了协作增益。仿真验证了理论分析的正确性和该策略的有效性。

The performance of spectrum sensing directly influences the efficiency of spectrum usage in cognitive radio systems. Considering the characters of spatial random distribution of secondary users, an efficient spectrum sensing strategy based on cooperation among secondary users is proposed to improve the spectrum sensing performance. The proposed strategy separates the space into cooperation cells, and intra-cell secondary users cooperatively sense the spectrum for cooperation gain. Based on the deducing and analysis of miss alarm probability and false alarm probability, it is known that the performance of the given strategy depends on the appropriate setting of the radius of cooperation cell and the detection threshold. Then the methods of setting these two parameters are given. It is also proved that the cooperation gain will degenerate when secondary users are distributed randomly in spatial domain. Simulation results validate the theoretical analysis in this paper and show that our proposed strategy performs well.