FFT算法实现EMI测试接收机时域扫描
EMI Test Receiver Time Domain Scan with FFT Algorithm
摘要 介绍了一种采用FFT算法实现接收机时域扫描的方法,时域扫描首先把整个频段划分为若干个子频率区间,在每个子频率区间进行时域采样,然后采用FFT算法并行处理,把信号变换到频率域,再把子频率区间组合在一起。与传统的频域逐点扫描相比,这种方法可以大幅度提高测试速度。
关键词 时域扫描;快速傅里叶变换;中频带宽;频率步进;ESU
Abstract In this article, a fast method for EMI time domain scan in FFT mode is
introduced. Compared with traditional frequency scan, this method decreases the
measurement time dramatically. This method divides the whole frequency span into
several sub-ranges, and over-samples each bandwidth and then operates each sub-
range with FFT algorithm simultaneously, and then the sub-ranges are combined
together in frequency domain,so the time is reduced by doing the FFT algorithm parallel
In the third part of this paper, the state of the art EMI test receiver R&S ® ESU which
including both conventional method and FFT method is introduced.
Key Words time domain scan, FFT, IF BW, step size;ESU