Radiation by patch antennas on a circular cylinder using the FE-BI method

Conformal antennas are typically mounted on surfaces which possess some curvature. However, no rigorous design analysis techniques are available for printed antennas on curved surfaces. Hence, most often planar designs are used and thus the curvature is not considered until expensive prototypes are built. Often, it is desirable to enclose each radiating element within a metallic cavity in order to suppress spurious substrate coupling. In the present paper the authors give a rigorous finite element-boundary integral (FE-BI) formulation for the analysis of wrap-around and cylindrical-rectangular cavity-backed patch arrays on a cylindrical surface. The paper presents the first rigorous solution for cavity-backed antennas embedded in a circular cylinder. The analysis technique is validated for single cylindrical-rectangular patches and for an array of four such elements. Results are also presented which give an understanding of the radiation properties for both circumferentially and axially polarized elements.<>