通过信号处理提高时域EMI的测量准确度

摘要

Analyse the time-domain data of spectrum with short-time FFT algorithm, the signal need to meet stationarity assumptions. Therefore, transient signal such as peak and impulse, cannot get the correct analysis results.Overlapping FFT is a powerful tool for time domain analysis of non-stationary signal.Bring in different overlapping depth, detailed analysis was carried out on the sample information. So it can avoid leakage frequency spectrum which the zero point of both window function sides may influence on the interference signal.It can seamless capture the transient signal, such as aperiodic, peak, impulse and frequency hopping.%利用短时FFT算法对时域数据进行频谱分析，信号需满足平稳性假设条件，因此对尖峰、脉冲等瞬态信号无法得到正确的分析结果。重叠FFT是对非平稳信号进行时域分析的有力工具，其引入不同的交叠深度，对采样信息进行精细分析，这样可以避免因为窗函数的两端零点对干扰信号可能造成的频谱泄露，实现对非周期、尖峰、脉冲以及跳频等瞬态信号的无缝捕获。