A High-Sensitivity Resonant Tangential E-Probe With Loaded Improved Dipole and Embedded Integrated Balun

In this paper, a high-sensitivity resonant probe for capturing tangential E-field component is fabricated on a four-layer printed circuit board. The resonant probe consists of an improved dipole employed to further enhance sensitivity, a resonator made up of open- and short-circuit stubs achieving specific resonance, and an integrated Marchand balun used to transform the differential-mode voltage to the single-end output and match the instrument port impedance match. Compared with the referenced broadband probe, the relative sensitivity of the proposed resonant probe in terms of |S
₁₂
| is enhanced by 13.21 and 14.82 dB for simulation and measurement, respectively. The absolute sensitivity in terms of the noise-equivalent field strength (NEFS) is 26.4 dBμV(Hz)
^1/2
. The measurements of the passive circuits (microstrip lines and coupled lines) and active circuit module are conducted to validate the resonant probe.