A Slot-Type <i>E_z </i> Probe With a Lower Effective Center

This article introduces a novel slot-type <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">E_z</i> probe engineered to achieve a lower effective center. This innovation addresses the limitation inherent in traditional <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">E_z</i> probes, which have a higher effective center and consequently suffer from low spatial resolution. The proposed probe incorporates a slot structure in its detection part, greatly lowering its effective center. Through simulation optimization, the slot structure is carefully designed to strike a balance between a high sensitivity and low effective center. To further elucidate the working principle of the slot probe, this article examines the effect of the probe's geometry on the effective center. The probe's design on a four-layer printed circuit board enables cost-effective fabrication without compromising stable performance. Operating within a frequency range of up to 30 GHz, the probe also effectively suppresses unwanted fields across a wide spectrum. Both simulation and measurement results corroborate the exceptional performance of the proposed probe, validating its efficacy in practical applications.