Design of a circular dual‐loop antenna for a GPS array element using an extended cavity structure

Abstract

This article proposes a circular dual‐loop antenna for a very small Global Positioning System array with an extended cavity structure. The antenna element consists of lower and upper circular loops printed on a high‐dielectric ceramic substrate and an extended cavity structure above the ground plane to improve the isolation characteristic. To demonstrate the suitability of the proposed antenna, antenna characteristics are measured in a full‐anechoic chamber, and its performances such as bore‐sight gain, mutual coupling, and near‐field as a function of extended cavity height are analyzed. The results confirm that the proposed antenna structure can minimize the gain degradation by improving the isolation characteristic and is therefore suitable for use in very small arrays.

Design of a Polarization-Selective EM Transparent Mesh-Type E-Shaped Antenna for Shared-Aperture Radar Applications

“…In such system configurations, the S-band radar is often employed for the surveillance of targets, whereas the X-band radar is used for the accurate tracking of targets [11,12]. In previous studies, various element types for the S-band and X-band radar systems have been reported, such as patch antennas [13][14][15][16][17][18], dipole antennas [13,14], and Vivaldi antennas [19]. In particular, patch-type antennas with a low profile and reduced radar cross section (RCS) characteristics are considered to be more suitable for military ship MFRs.…”