A Resonant Magnetic Field Probe With Enhanced Sensitivity Using Quarter-wavelength Impedance Transformer

In this paper, a novel resonant magnetic probe is proposed. The resonance of the probe is achieved by a parallel-plate and metal loop, which provides the parasitic capacitor C and inductor L respectively. Moreover, a quarter-wavelength high impedance line is proposed and inserted into the transmission part of the probe. This line introduces additional multi-reflections along the probe transmission part. Under the optimize line length, such multi-reflections will enhance the output voltage of the probe. Numerical and measurement results show that the sensitivity of the proposed probe can be increased by more than 10 dB at a resonant frequency of 1.575 GHz, in comparing with the reference wideband probe.