3-D Printed Dielectric Dome Array Antenna With ±80° Beam Steering Coverage
Lin Xiao, Shi‐Wei Qu, Shiwen Yang
Abstract
An efficient design of a 3-D printed dielectric dome array (DDA) antenna featuring ultrawide-angle beam scanning is presented in this article. Instead of using optimization tools, the inner and outer contours of the dielectric dome lens (DDL) are determined by the derived phase distribution <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\phi (\theta)$ </tex-math></inline-formula> over a dome surface <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$r(\theta)$ </tex-math></inline-formula> . The scan gain of the DDA can be manipulated by properly choosing the defined scan amplification factor <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$K(\theta)$ </tex-math></inline-formula> of the DDL. After determining the contours of the DDL, two finite-by-infinite 1-D DDA models are constructed to predict the E- and H-plane scanning performances, respectively, wherein both the full-wave performances of feed array and the effect of multiple reflections at the air–dielectric interfaces are considered. Since the phase distribution over the planar array is nonlinear due to the presence of the DDL, the array excitation phases are optimized by the particle swarm optimization (PSO) method with the optimization goal of the maximum gain at each scan angle. As a proof of concept, a 3-D printed DDL fed by an <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$8 \times 8$ </tex-math></inline-formula> E-shaped patch array at 20 GHz is manufactured and tested. When combined with the DDL, a ±60° scan range of the planar array can be extended to ±80° with relatively flat scan gain. The experimental results are in acceptable agreement with simulations, verifying the feasibility of the DDL design.