A Novel Dual-Component Magnetic Probe for Near-Field Scanning Measurement

This letter proposes a novel dual-component magnetic probe for near-field scanning measurements. Unlike traditional detection structures based on a U-shaped or differential loops, this work proposes a new integrated configuration that combines a U-shaped loop with a pair of nondifferential symmetric shorted loops. The proposed integrated configuration enables simultaneous detection of two orthogonal magnetic-field components (<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$H_{x}$</tex-math> </inline-formula> and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$H_{y}$</tex-math> </inline-formula>). The U-shaped loop can measure the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$H_{y}$</tex-math> </inline-formula> component based on the principle of differential mode operation, while the identical shorted loops can measure the other orthogonal <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$H_{x}$</tex-math> </inline-formula> component through common mode excitation. The proposed dual-component magnetic probe is fabricated by a four-layer printed circuit board (PCB), characterized by a near-field measurement system. The simulated and experimental results prove that the magnetic probe has improved center positioning and dual-component measurement capability, and a greater than -50 dB of detection sensitivity at 2–8 GHz.