LAUSR

A miniaturized ultrawideband active electric probe with high sensitivity for near-field measurement is proposed in this article. The probe is designed with a four-layer printed circuit board (PCB) with mainly two chips, an amplification chip (HMC797APM5E) which can work from dc to 22 GHz and a power management chip (HMC980LP4E). The probe can work from 9 kHz to 18 GHz with 15-dB average gain compared to the passive probe, and the flatness is about ±4 dB in terms of $\vert S_{21}\vert $ (transfer factor) from 2.5 to 18 GHz. The maximum size of the probe is 64 mm $\times41.5$ mm with 1-mm spatial resolution, and the width of the tip is only 4.1 mm, so the probe can handle most test environments. On the whole, the probe is very efficient for near-field measurement to detect weak signals in a wide bandwidth.