To spectral analysis of vibration signals, proper amplitude correction to the spectrum of the windowed signal is required, which can eliminate the inconvenience of the spectrum amplitude evoked by windowing. Generally, there are tow rules which should be observed. The first one is that the amplitude of the spectrums should be equal. The second one is that the power of the spectrums should be equal. Through the theoretical a-nalysis and numerical simulation, the correcting factor calculation method which utilizes spectrum features of the sine calibration is presented and analyzed. This method is based on the first rule and many application experiences in the field of aircraft engine vibration processing. Besides this, the amplitude correction factors of fives widely used window are presented too.%在振动信号频谱中,为了消除加窗导致的信号频谱幅度的不一致问题,通常需要对加窗后信号的频谱进行幅值修正.一般情况下,幅值修正过程遵循两个原则:幅值相等原则和能量相等原则.结合航空发动机振动信号处理中的类似问题,遵循幅值相等原则,结合工程实践,通过理论分析和数值仿真分析的方法,提出了一种基于正弦校准信号的加窗幅度修正的方法.该方法利用正弦校准信号频谱的特点,以及相关的信号处理理论和方法分析得出,加窗幅度修正系数为窗函数序列的直流分量.此外,依据该方法给出了5种常用窗函数的加窗幅值修正系数,并用数值仿真的方法对其正确性进行了验证.
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