说明：  移频复调制ZOOMFFT能以指定的、足够高的采样频率分析频率轴上任一窄带内信号的频谱结构，在序列变换点数相同的情况下，ZOOMFFT能获得更高的频率分辨率
(The frequency shift the complex modulation ZOOMFFT to specified former spectrum of the signal within a narrow band structure, a sufficiently high sampling frequency analysis of the frequency axis, in the case of the same sequence transform points, ZOOMFFT obtain a higher frequency resolution)