A Miniature Multi-Component Probe for Near-Field Scanning

In this paper, an electromagnetic probe is proposed for the near-field scanning. Its detection section is made of a miniature loop-wire hybrid structure, which can measure H
_x
, H
_y
, and E
_z
simultaneously. It is optimized to achieve a wide working band from 0.1 to 15 GHz. The calibration and measurement error of the probe are discussed in detail. The probe is fabricated as a four-layer printed circuit board (PCB) with the RO4350B dielectric. A near-field scanning system with the manufactured probe is set up to test the near fields above a Z-type microstrip line and an inverted-F antenna. By comparing the measurement and simulation results, the accuracy of the proposed multi-component probe is verified. It greatly improves the near-field scanning efficiency compared to the traditional single-component probe.