Miniaturization-Oriented Design of Spline-Parameterized UWB Antenna for In-Door Positioning Applications

Abstract

Design of ultra-wideband antennas for in-door localization applications is a challenging task that involves development of geometry that ensures appropriate balance between the size and performance. In this work, a topologically-flexible monopole has been generated using a stratified framework which embeds a gradient-based trust-region (TR) optimization algorithm in a meta-loop that gradually increases structure dimensionality. The optimization has been performed using a composite objective function that maintains acceptable size/performance trade-off. The final design features a reflection below -10 dB within the UWB spectrum and a small footprint of only 182 mm2. The considered method has been benchmarked against a standard TR-based routine executed directly on a multi-dimensional representation of the antenna model.