Full-wave analysis of PEC-embedded U-Slot microstrip patch elements

Cavity-backed slot antennas have been a popular choice for element design in conformal array antennas. However in some cases it is actually desired to examine if microstrip patch elements can be used as replacements for slot antennas by embeding them in perfect conductors (PEC). The investigation reported here examines the VSWR and radiation patterns characteristics of a wideband U-Slot microstrip patch element used as a retro-fit (or substitute) for the cavity-backed slot radiating from a rectangular aperture in a PEC circular cylinder. Specifically, the results reported here examine the effects of curvature on the VSWR and equatorial (Theta = 90deg) plane radiation patterns for increasing cylinder electrical radius, where Theta = 0deg defines the cylinder generator axis.