Analysis and Optimization of Airy Beams for Resilient Communications and Wireless Power Transfer

Sammanfattning

This thesis investigates the focusing performance and robustness of auto-focusing Airy beams in near-field wireless communication scenarios. Through a combination of simulations using MATLAB (Matrix Laboratory, a numerical computing environment) and full-wave electromagnetic simulations in FEKO (Feldberechnung für Körper mit beliebiger Oberfläche, an electromagnetic solver developed by Altair), this study systematically compares auto-focusing Airy beams, which are formed by the superposition of two Airy beams with opposite main lobe phases, to conventional phase-conjugated beamforming. The results demonstrate that dual Airy beams formed with a discrete number of array elements (instead of a continuous source) can achieve sharp near-field focusing and exhibit unique self-healing properties in the presence of obstacles. In particular, Airy beams exhibit strong robustness against obstacles placed within their “silent zone” (a low-energy region between main lobes), maintaining a relatively high field strength around the target focal point. However, even under equal excitation power, the phase-conjugated beam in general achieves a higher field strength at the reference plane around the target focal point. The thesis further examines the effects of array aperture truncation and focal shift, finding that under certain conditions, Airy beams may outperform phase-conjugated beams, though this advantage is highly conditional and sensitive to array geometry and obstacle placement. Limitations related to discretization of the source (into array elements) and physical realization are also discussed in detail. Finally, the thesis outlines potential directions for future research, including machine learning-based optimization, experimental validation, and the extension to two-dimensional Airy beams. The findings provide new insights into the potential and limitations of Airy beams for robust near-field applications.