Non-uniform vertically stacked microstrips of high radiation efficiecy at millimeter waves

Abstract

A two-layered vertically stacked microstrips structure is investigated and found to possess a weakly attenuated leaky mode, which can be applied to realize a high-gain, narrow-beam antenna. The attenuation rate can be further reduced by sophisticatedly controlling the widths of metal strips. The reduction of attenuation rate can improve the directivity and bandwidth of antenna abundantly. A new tapered line termination is also illustrated in this paper. This structure can greatly shorten the antenna length by more than 16%.