Optimization and Additive Manufacture of a Miniature 3-D Pixel Antenna for Dual-Band Operation

Abstract

This paper presents the design, manufacture, and experimental validation of a novel 3-D pixel antenna with volume-filling characteristics, and the design is based on our Method of Moments (MoM) solver that is efficiently coupled with a global/local optimizer for tailoring the antenna shape and concurrently selecting the location of the feeding port and shorting straps. The design, aimed at operating in the ISM bands of 2.45 GHz and 5.8 GHz, has dimensions under one-tenth of wavelength at the lowest frequency of operation. The optimization results are cross-validated using a commercial full-wave simulator, with a deviation of the reflection coefficient across the operating bands within 3%, showing also a high antenna efficiency of 99.6% and a gain of 1.06 and 4.53 dBi at the matching frequencies, with radiation patterns predominantly oriented towards the top hemisphere. Tolerance and parameter sensitivity studies were also performed. A scaled-up prototype of the antenna was built at a very low cost using standard additive manufacturing techniques, featuring a very good agreement between simulation and measurements, which proves the feasibility of this new kind of complex shape antennas in further applications where compact internal antennas are required.