This paper develops an active magnetic near field probe (H-field probe) by using a fourlayer printed circuit board (PCB) technique. Two-turn detection structure and a low noise amplifier are used to improve probe's frequency response. The two-turn detection structure can maximize the use of PCB stack resources, and a 14.5 dB gain amplifier can increase signal output capability. The probe can then be used for electromagnetic compatibility (EMC) test from 150 kHz to 3 GHz. Compared with traditional active shielded-loop H-field probe (TAHP) with loop area of 500 𝜇m 2 , the frequency response of the proposed probe can improve 20 dB at 0.5 GHz. Different from the method of comparing the sensitivity of the probe only through the frequency response, this paper measures and analyzes the real sensitivity of the probing device composed of the proposed probe. Under the condition of the same receiver parameter setting, the sensitivity at 0.5 GHz is increased by 11.7 dB compared with commercial passive probing device and 20.2 dB at 0.5 GHz compared with the probing device with TAHP device. It reaches −32.4 dB µA. In addition, the proposed probe has acceptable spatial resolution of 1.28 mm at 1 GHz, which is more suitable for printed circuit board level EMI analysis.
A miniature practical active magnetic field (H-field) probe with 0.5 mm  0.15 mm loop size is designed for electromagnetic interference analysis in electronic systems from 150 kHz to 12 GHz. This probe is fabricated in a four-layer printed circuit board using high-performance and low-loss Rogers material (RO4350B). A low noise amplifier with 14 dB-gain is applied to amplify the radio frequency detect signal. The spatial resolution of the proposed probe is verified under the microstrip with different widths (1.55 and 0.24 mm). In addition, the verification results indicate that the proposed small loop active shielded H-field probe can obtain the better spatial resolution of 422 μm with liftoff = 100 μm. Regarding to the sensitivity of the probe, the proposed probe realizes 16.7 dB μA at 3 GHz with the liftoff = 100 μm. compared with other commercial probes and a reference probe, the proposed probe has better spatial resolution at 150 kHz-12 GHz and sensitivity at 1.5-12 GHz.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.