Electrooptic sensor for near-field measurement

This paper presents a novel electric field measurement system utilizing optical technology, which has been developed, tested, and calibrated for the near-field measurement in the frequency range up to 1.8 GHz. The measuring probe is passive, all-dielectric, electromagnetic interference (EMI)-immune, and provides the information on the field strength, frequency, and phase. The achieved measurement resolution and minimum mode measurable fields were 10 V/m, with a spatial resolution of 10 mm. A finite-difference time-domain (FDTD) algorithm for solving Maxwell's equation was used to assess the field perturbation by the presence of the measuring probe and the suitability for the near-field measurement.