New Convenient Composite Probes With 0°/180° Hybrid Couplers for Near-Field Scanning Measurements

Abstract

In this work, we propose two new convenient composite probes with 0°/180° hybrid couplers for near-field scanning measurements. The proposed probes (denoted as A and B) integrate a U-shaped loop as the driven element and a parallel U-shaped loop as the parasitic element, two different 0°/180° hybrid couplers, two interconnected vias, and a pair of 50- $\Omega $ striplines. The design leverages the driven and parasitic U-shaped loops to concurrently detect electric-field (E-field) and magnetic-field (H-field) components and improve detection sensitivity, thereby extending the probes’ capability to capture a wider spectrum of electromagnetic fields. The integrated 0°/180° hybrid couplers enable precise differentiation and superposition of outputs from the driven loop, effectively isolating the E-field and H-field responses. Crucially, this architecture permits direct connectivity to oscilloscopes, eliminating dependence on vector network analyzers (VNAs) for electromagnetic component sensing. The design, simulation, measurement, and characterization of two Probes A and B are detailed. Measurement results demonstrate these probes’ enhanced sensitivity and dual-field measurement capability. The ability of directly link to oscilloscopes, bypassing the need for a VNA, makes these probes highly suitable for practical interference source location testing.