α-稳定噪声环境下空时分组码的性能分析

Performance analysis of space-time block coding over fading channels with α-stable noise

针对非高斯噪声环境衰落信道中的正交空时分组码(OSTBC)性能进行研究.基于非高斯噪声建模理论,将空时分组码系统的噪声环境建模为对称α-稳定分布噪声,给出噪声采样信号的概率密度函数及特征函数.推导了基于最大似然(ML)译码的OSTBC系统的误符号率(SER),并且对不同衰落信道条件下系统性能进行估计.仿真结果表明,OSTBC的性能随噪声特征指数α的减小而降低.当噪声脉冲性较强时,系统对于Nakagami-m和Rician衰落信道的参数m和K不再敏感.

The performances of orthogonal space-time block coding （OSTBC） over fading channels with α-stable noise are investigated. Based on the theory of non-Gaussian noise modeling, the noise environments of STBC systems can be modeled as α - stable distributed and the probability density function and characteristic function of the noise signals in OSTBC systems are presented in terms of this model. The average symbol error rate （SER） is derived for the maximum likelihood （ML） receiver in α-stable noise environment and the performances over various fading channels are evaluated. The simulation results show that the performances of OSTBC degrade with the characteristic exponent a decreasing and are insensitive to fading parameter m of Nakagami-m channels as well as Rician factor K of Rician channels with respect to highly impulsive noise.