Design of a dual‐mode annular ring antenna with a coupling feed

Abstract

A dual-mode annular ring antenna for both global positioning system (GPS) and satellite digital multimedia broadcasting (S-DMB) is designed. The proposed antenna consists of a coupling feed line and four slots on an annular ring patch. A gap between the feed line and the annular ring patch is used for an input impedance matching; the slots are used for adjusting the resonant frequency of the TM 21 mode at the DMB frequency. The antenna was fabricated and measured. The antenna resonates at the GPS and DMB frequencies with suitable bandwidths. It has a broadside radiation pattern in the GPS band and a conical beam radiation pattern in the DMB band.

Investigation for impact behavior of composite surface antenna

“…A gap coupling between annular ring and a 50 Ω feed line is used at the maximum field position of the two modes; and four slots are cut into the patch to adjust the resonant frequencies [5]. The patch and ground are printed on an FR4 substrate (ε r =4.4, δ=0.02) of thickness 0.4 mm, and the relative permittivity of the honeycombs is 1.1.…”