脉冲噪声下基于循环相关熵的PSK信号码速率估计

针对现有相移键控(PSK)信号码速率估计方法在脉冲噪声下性能退化甚至失效的问题,提出一种循环平稳理论框架下基于相关熵的码速率估计新方法.构造信号的循环相关熵函数,并理论推导给出在二相相移键控(BPSK)信号下的循环相关熵函数.该方法可通过检测PSK信号循环相关熵函数的离散谱线实现码速率估计,不需要噪声的先验信息,且能够直接利用FFT计算信号的循环相关熵函数的延迟切片,实现简单.仿真结果表明,所提出方法能有效抑制脉冲噪声,尤其在强脉冲噪声环境下,具有良好的PSK信号码速率估计性能.

Symbol rate estimation of PSK signals based on cyclic correntropy in impulsive noise

In order to solve the problem that existing algorithms for the symbol rate estimation of phase shift keying (PSK) signals will undergo performance degradation or even become invalid in the Alpha stable noise environment, a novel cyclic correntropy based method under the cyclostationary framework for symbol rate estimation of PSK signals is proposed. The paper presents the cyclic correntropy function, and deduces the cyclic correntropy function expression of binary phase shift keying (BPSK) signals theoretically. This method is easy to be realized owing to the adoption of fast fourier transform (FFT) in calculating the one-dimensional slices of the cyclic correntropy function, and can estimate the symbol rate by detecting the discrete spectral lines of the PSK signal cyclic correntropy function. Moreover, it does not require the prior information of the impulsive noise. The simulation results show that the proposed method can suppress the Alpha stable noise efficiently, and has excellent symbol rate estimation performance of PSK signals, especially in the strong impulsive noise environment.