数字示波器宽带探头系统的校准研究

微波射频芯片进行时域测量时,数字示波器的宽带探头是测试芯片的一个关键子系统,为准确测量芯片,必须要清楚示 波器探头系统的传输性能。 为此,设计了一种包含接地共面波导的数字示波器宽带探头校准系统,依据校准系统的信号传输特 性,用反卷积求出数字示波器宽带探头系统的频率响应,并计算其带宽,以实现对该探头系统的校准。 之后用该方法对 Keysight Infiniimax 高频差分有源探头系统进行了校准,得到其带宽数值约为 12 GHz 与标称带宽 12 GHz 相符,表明设计的校准系统合 理可行。

Calibration of broadband probe system of digital oscilloscope

When microwave RF chips are measured in the time domain, the broadband probe of digital oscilloscope is a key subsystem used to test the chip, and the transmission performance of the oscilloscope probe system must be clear for accurate measurement of the chip. So, the calibration system containing a grounded coplanar waveguide is designed to calibrate a broadband probe of digital oscilloscope. According to the signal transmission characteristics of the calibration system, the frequency response of the digital oscilloscope broadband probe system is obtained by deconvolution, and its bandwidth is calculated, which realizes the calibration of the probe system. The Keysight Infiniimax high-frequency differential active probe system is calibrated by this method, and the bandwidth value of about 12 GHz is in accordance with the nominal bandwidth of 12 GHz, indicating that the calibration system is reasonable and feasible.