Design of a miniaturized dual-band antenna for improved directivity using a dielectric-loaded cavity

ABSTRACT This article proposes the design of a dual‐band global positioning system (GPS) antenna using a high‐permittivity dielectric‐loaded cavity. The cavity structure is filled with a dielectric material to miniaturize the size, and its width and depth are adjusted to maximize the front‐to‐back ratio for high directivity. Dual‐band circular polarization characteristics are achieved by placing two radiating polygon loops at the aperture of the cavity, and the loops are electromagnetically coupled to a microstrip line for a coupled feeding network. The proposed antenna is fabricated, and its antenna characteristics are measured in a full anechoic chamber. The results demonstrate that the antenna is suitable for dual‐band GPS applications with high bore‐sight gain values of 3.4 dBic at 1.2276 GHz and 3.7 dBic at 1.5754 GHz. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:1591–1595, 2016