α稳定分布噪声下数字频移键控信号的分数低阶循环谱分析  

Fractional lower order cyclic spectrum analysis of digital frequency shift keying signals under the alpha stable distribution noise

作　　者：刘高辉[1] 张娟娟[1] 

机构地区：[1]西安理工大学自动化与信息工程学院,西安710048

出　　处：《电波科学学报》2017年第1期65-72,共8页Chinese Journal of Radio Science

基　　金：国家自然科学基金(No.61671375)

摘　　要：针对α稳定分布噪声环境下数字通信信号的二阶与高阶循环统计特征显著退化问题,结合分数低阶矩和共变理论对二进制频移键控(Frequency Shift Keying,FSK)信号的分数低阶循环谱公式进行了理论推导,并对2FSK信号在不同混合信噪比、分数阶因子和特征指数条件下的分数低阶循环谱进行了详细的仿真分析.理论和仿真结果表明:2FSK信号分数低阶与二阶的循环谱结构相同,其谱峰对应的循环频率相同,谱峰的幅度值不同,取决于循环谱的阶因子.相对于在低混合信噪比下失效的二阶循环谱,分数低阶循环谱对α稳定分布噪声具有更强的抗干扰性和适用性.Aiming at the significant degradation of the statistical characteristics of the second and higher order cycle of the digital communication signal in the alpha stable distributed noise environment, the fractional lower-order cyclic spectrum formula of the frequency shift keying（FSK） signal is deduced with the fractional lower-order moments and the covariant theory. Then, the low-order cyclic spectrum charac- teristics of 2FSK signal under different mixed signal-to-noise ratios, fractional factors and characteristic ex- ponents were analyzed in detail. The theory and simulation results show that the low-order and second-or- der cyclic spectrum structures of the 2FSK signal are the same, and the peak frequencies of the 2FSK signal are the same, but the amplitude of the spectrum is different that depending on the order factor of the cyclic spectrum. Fractional lower-order cyclic spectrum has stronger anti-interference and applicability to alpha stable distributed noise.

关 键 词：Α稳定分布噪声 2FSK信号 分数低阶矩 共变理论 混合信噪比 

分 类 号：TN911.7[电子电信—通信与信息系统]