Small antenna over an engineered ground plane

We present a study on the performance of a small antenna over an engineered ground plane. The paper is mainly divided into two parts. In the first part, a miniaturized simple surface is designed to have in-phase reflection to incident waves normal to its surface. Such 1-D artificial magnetic conductor surface (AMC) is then extended to a 2-D design. Reduced size versions including loss effects are discussed. Comparisons between simulations and measurements are shown. In the second part of this paper, a small wire is placed in close proximity to a single unit cell of the surface. A simple model is presented to clarify how matching is achieved. The footprint of such system, realized using FR-4, encompassing the radiator and the AMC surface on a finite ground plane is about 0.04 of the free space wavelength, with a maximum gain of 4 dBi.