A Broadband Active Dual-Component Magnetic Probe for Near-Field Measurement

Abstract

This work first presents a broadband active dual-component magnetic probe with high sensitivity for near-field measurements. The proposed active magnetic probe is mainly composed of two orthogonal short-circuit loops as signal receiving part, a pair of strip lines as signal transmission part, two low-noise amplifiers (LNAs) as signal enhancement part, and a pair of subminiature version A (SMA) connectors as signal output part. Note that two orthogonal short-circuit loops are used to simultaneously sense two magnetic-field components in different directions and improve detection efficiency. Moreover, a pair of broadband LNAs are integrated into the probe to enhance detection sensitivity. Finally, in order to verify the effectiveness of the design, the proposed active magnetic probe is manufactured on a four-layer printed circuit board (PCB) and characterized by a near-field test system. Measurement results demonstrate that the proposed active magnetic probe can not only measure two orthogonal magnetic components simultaneously but also has high detection sensitivity and wide working bandwidth from 0.3 to 20 GHz.