FDTD Computation of Human Eye Exposure to Ultra-wideband Electromagnetic Pulses

TL;DR

This study uses FDTD simulations to analyze human eye exposure to UWB electromagnetic pulses across multiple frequency bands, revealing safety advantages over continuous waves and providing detailed interaction insights.

Contribution

It presents a comprehensive FDTD-based computational model for human eye exposure to UWB pulses, including detailed dielectric properties and geometrical resolution, advancing safety assessment methods.

Findings

UWB pulses interact with eye tissues similarly to CW at corresponding frequencies.

UWB exposure is significantly safer than CW under identical conditions.

The model accurately captures complex broadband electromagnetic interactions.

Abstract

With an increase in the application of ultra-wideband (UWB) electromagnetic pulses in the communications industry, radar, biotechnology and medicine, comes an interest in UWB exposure safety standards. Despite an increase of the scientific research on bioeffects of exposure to non-ionizing UWB pulses, characterization of those effects is far from complete. A numerical computational approach, such as a finite-difference time domain (FDTD) method, is required to visualize and understand the complexity of broadband electromagnetic interactions. The FDTD method has almost no limits in the description of the geometrical and dispersive properties of the simulated material, it is numerically robust and appropriate for current computer technology. In this paper, a complete calculation of exposure of the human eye to UWB electromagnetic pulses in the frequency range of 3.1-10.6, 22-29, and 57-64 GHz is performed. Computation in this frequency range required a geometrical resolution of the eye of $\rm 0.1 \: mm$ and an arbitrary precision in the description of its dielectric properties in terms of the Debye model. New results show that the interaction of UWB pulses with the eye tissues exhibits the same properties as the interaction of the continuous electromagnetic waves (CW) with the frequencies from the pulse's frequency spectrum. It is also shown that under the same exposure conditions the exposure to UWB pulses is from one to many orders of magnitude safer than the exposure to CW.