Jinlin Liu

Design of transition from WR-15 to inverted microstrip gap waveguide

Currently gap waveguide technology has revealed strong competitiveness for millimeter wave wireless applications. Specifically, this new topology of waveguide technology provides advantages of low loss, high quality factor and easy RF packaging. In this paper we present the design methodology of millimeter-wave transition from standard WR-15 rectangular waveguide to inverted microstrip gap waveguide. Furthermore, a more practical power divider from standard WR-15 rectangular waveguide to inverted microstrip gap waveguide is also introduced. Both structures are vertical and there is no additional need for any complex modification of the waveguide structure to achieve compatibility between the two structures. The proposed two transitions cover the whole unlicensed 60 GHz band from 57 to 66 GHz in order to be widely utilized as an interface between gap waveguide feed networks and equipment components with WR-15 ports. The simulated results show promising S-parameters.

Slot antenna array unit cell directly fed by inverted microstrip gap waveguide

Inverted microstrip gap waveguide is mechanically flexible millimeter wave transmission line. This paper describes a single-layer slot antenna array unit cell at 60-GHz designed by using this inverted microstrip gap waveguide technology. This antenna unit mainly consists of a 2×2 slot layer and corporate-feed networks. The unit-cell shows more than 14.6% bandwidth over 57–66 GHz band with 10-dB return loss. Infinite array environment has been utilized later to determine overall efficiency for bigger 16×16 antenna array which is around 70% with a directivity value of 33.5 dBi between 57–66 GHz.