基于NTN校准的等效采样示波器任意频率栅相位响应重构

Phase response reconstruction of arbitrary frequency grid for equivalent sampling oscilloscope based on NTN calibration

研究提出了一种通过测量等效采样示波器幅度响应来获得其相位响应的算法。此方法是基于Kram ers-Kron ig关系式并配以基于NTN校准的相位响应测量实现的。实例证明:虽然Kram ers-Kron ig变换计算时的截断造成了相位估计上非常大的误差,但是此误差可以通过少量的正交基函数拟合出来。作为一个实例,本文利用NTN校准和扫频法校准的结果获得了等效采样示波器的复频率响应,在1 MHz^50 GHz频率范围内,其频率分辨率达到了1 MHz。重构出的相位响应标准不确定度小于0.6°。结果表明:此方法可以重构出等效采样示波器任意频率栅复频率响应。

Describes an algorithm for determining the minimum phase response of equivalent sampling oscilloscopes.The procedure is based on Kramers-Kronig relation in combination with the harmonic phase response measurement of NTN calibration.Although the truncation of Kramers-Kronig transform gives rise to large errors in estimated phase,these errors can be fitted using three basis functions.As an example,we got the phase response reconstruction of sampling oscilloscope in frequency domain;its frequency resolution achieves 1MHz in the frequency range from 1 MHz^50 GHz,and the phase uncertainty of the phase response is less than 0.6°.These results are based on the data obtained using an NTN technique in combination with swept-sine calibration procedure.The above results show that the algorithm can be used to obtain fine phase response of equivalent sampling oscilloscopes.