It is now widely used for signal monitoring, interception, direction finding, with the software can automatically observing frequency occupation and so on.

广泛用于信号监测、侦听、测向，配合相关软件，能自动观测频率占用度等。

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This effect can be measured in either the time domain by observing the rate of decay of voltage or in the frequency domain by measuring phase shifts between sinusoidal currents and voltages.

这个效应可以在时间域通过观测电压的衰变率来测量，也可以在频率域通过正弦电流和电压之间的相变来测量。

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By observing the periods of the target length variant, the frequency of nutation is deduced.

通过观测一维像序列的长度变化周期，提取目标的章动频率；

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