一、引言 在信号分析领域中,往往采用傅立叶变换对时域信号进行处理,以便在频域下对信号进行分析。在进行傅立叶变换时,不可避免地存在信号的长度选择问题。 在时域内盲目地选择信号长度会产生不正确的频谱,在电力系统以及生物医学中信号多数是非平稳的随机过程,这种情况下正确 I. INTRODUCTION In the field of signal analysis, the Fourier transform is often used to process time-domain signals for signal analysis in the frequency domain. In the Fourier transform, there is inevitably the length of the signal selection problem. Blindly selecting the signal length in the time domain produces an incorrect spectrum. In power systems and biometrics, most of the signals are nonstationary random processes. In this case, the correct