A Low-Profile Dual-Band Surface Wave Antenna With a Monopole-Like Pattern

A dual-band surface wave antenna (DBSWA) that realizes a monopole-like radiation pattern with a low-profile configuration is designed and measured. The antenna consists of two parts: a center-fed modified crosspatch to excite surface waves at two frequency bands, and a thin dielectric slab loaded with periodic patches to support the propagation of the surface waves. The surface wave property and radiation mechanism of the DBSWA are described, and parametric studies are performed to understand the dual-band characteristics of the antenna. The proposed antenna with only 3 mm thickness (< 0.05 lambda) is fabricated and tested, which resonates at 4.2 and 4.9 GHz. The corresponding impedance bandwidths and gains are 1.10% and 4.9 dBi for the low frequency band and 3.94% and 5.4 dBi for the high frequency band.