A Numerical Exposure Assessment of Portable Self-Protection, High-Range, and Broadband Electromagnetic Devices

Abstract

In this paper we perform a safety assessment of portable self-protection, high-range and broadband electromagnetic devices. Such instrumentation is particularly common in military equipment, for instance in the form of back-pack systems. Our aim is to analyze the effect on human body of high-power and broadband radiating systems, especially considering their near-field operating region. Hence, differently from the typical approach in the literature, we design through a numerical electromagnetic solver a common back-pack device operating over a large bandwidth (40-2700 MHz), employing ad-hoc compact and broadband antennas. Moreover, we place close to this system a realistic body phantom model (Hugo) in order to accurately characterize the effects in terms of SAR deposition and hot-spots localization, considering the tissues dispersive properties. The results show that the SAR limits can be likely overcome by the typical power levels of these systems, thus requiring a careful safety assessment. Guidelines are provided in the manuscript in order to decrease the SAR levels by opportunely selecting the back-pack radiating elements position. This study can be helpful to serve as a reference to accomplish a complete and accurate analysis on the e.m. safety of similar devices and, further, to undertake suitable containment measures to reduce exposition.