Computational and experimental characterization of EMF exposure at 3.5 GHz using electro-optical probes

With its recent advances, electro-optical (EO) technology stands out as a promising alternative to conventional near field measurement instrumentation due to their miniature size and dielectric structure that does not interfere with the measured field. In this article we have used a type of commercially available EO measurement system to evaluate both in-air and in-liquid electric (E) field strength in the proximity of a custom fabricated antenna operating at 3.5 GHz frequency. Comparative computational and experimental results are presented and analysed with respect to the medium, antenna power, distance from the antenna and based on the guidelines limiting human exposure to EMFs. Present findings suggest that at their current technological development, the investigated EO probe response becomes inadequate for channel bandwidths commonly used in new generation communication standards (20 MHz and higher), especially if low emit powers are used (below 30 mW).