α稳定噪声中基于正态变换的次优接收机
李旭杰;赵鸿燕;杨成胡
【期刊名称】《电路与系统学报》 【年(卷),期】2012(017)003
【摘要】通信信道中的冲激噪声通常可由对称的α稳定分布(SαS)描述.由于SαS的概率密度函数(PDF)无闭式表达,因此基于 Neyman-Pearson准则的解析的最优接收机也不存在.采用解析模型——双参数柯西-高斯混合模型( BCGM)近似SαS的PDF,导出了基于正态化变换的零记忆非线性(NZMNL)限幅器,NZMNL限幅器使得α稳定噪声变换为标准的正态分布噪声.分析了基于该限幅器次优接收机的误码率性能,仿真结果表明对于噪声参数α∈(1.5 2.0]时,所提出接收机的性能优于经典的柯西接收机和钳位接收机.%The impulsive noise in the channel is modeled usually by the symmetric α-stabLe (SαS) distribution. The optimal receiver cannot be analytically derived as a closed form expression, for the density function of SaS is not available. In this paper, by using the bi- parameter Cauchy-Gaussian mixture (BCGM) model to approximate the SaS density, we devise a new zero-memory nonlinearity limiter (ZMNL) receiver, which transforms the SaS noise to a standard Gaussian one, and can be regarded as a normalization-based ZMNL (NZMNL) limiter. For α∈[1.5 2.0], the most typical impulsive noisy channels, simulation results indicate that the NZMNL based receiver outperforms two classical receivers, Cauchy and limiter plus integrator based ones.
α稳定噪声中基于正态变换的次优接收机
