A New Method to Improve the Detection Sensitivity of Differential Magnetic-Field Probe for Near-Field Scanning

In this communication, a new method is proposed to improve the detection sensitivity of the differential magnetic-field probe for near-field scanning. In order to prove the rationality of this method, two differential magnetic-field probes (Probes A and B) with multiple parasitic loops are investigated. First, a conventional differential magnetic-field probe is theoretically analyzed and studied. Second, a pair of parasitic loops are introduced into a differential magnetic-field probe (Probe A) to enhance the detection sensitivity. Third, two pairs of parasitic loops are inserted into the differential magnetic-field probe (Probe B). The corresponding analysis is also given and discussed. Moreover, in order to verify the performance of these probes (Probes A and B), two of the simulated models are printed and manufactured based on six-layered and eight-layered printed circuit boards (PCBs), respectively. A standard microstrip line is applied for calibrating and characterizing these probes. The measured and simulated results reveal that the proposed method could significantly improve the detection sensitivity of differential magnetic-field probes.