2<formula formulatype="inline"><tex Notation="TeX">$\times$</tex> </formula>2-Slot Element for 60-GHz Planar Array Antenna Realized on Two Doubled-Sided PCBs Using SIW Cavity and EBG-Type Soft Surface fed by Microstrip-Ridge Gap Waveguide

Abstract

A wideband 2×2-slot element for a 60 GHz antenna array is designed by making use of two double-sided printed circuit boards (PCBs). The upper PCB contains the four radiating cavity-backed slots, where the cavity is formed in substrate-integrated waveguide (SIW) using metalized via holes. The SIW cavity is excited by a coupling slot. The excitation slot is fed by a microstrip-ridge gap waveguide formed in the air gap between the upper and lower PCBs. The lower PCB contains the microstrip line, being short-circuited to the ground plane of the lower PCB with via holes, and with additional metalized via holes alongside the microstrip line to form a stopband for parallelplate modes in the air gap. The designed element can be used in large arrays with distribution networks realized in such microstrip-ridge gap waveguide technology. Therefore, the present paper describes a generic study in an infinite array environment, and performance is measured in terms of the active reflection coefficient S11 and the power lost in grating lobes.The study shows that the radiation characteristics of the array antenna is considerably improved by using a soft surface EBGtype SIW corrugation between each 2×2-slot element in E-plane to reduce the mutual coupling.The study is verified by measurements on a 4×4 element array surrounded by dummy elements and including a transition to rectangular waveguide WR15.Index Termsgap waveguide, slot antenna array, soft and hard surfaces, EBG surface, substrate integrated waveguide (SIW).

A Ridge Gap Waveguide fed apperture-coupled microstrip antenna array for 60 GHz applications

“…Recently, the gap waveguide technology introduced in [2][3][4] overcomes the problem of good electrical contact associated with mechanical assembly. To date, some wideband high gain and efficiency array antennas have been realized based on gap waveguide technology in in different frequency range [5][6][7][8][9][10][11]. This gap waveguide technology uses the cut-off a PEC-PMC parallel plate waveguide configuration to control desired electromagnetic propagation between the two parallel plates without the requirement of electrical contact.…”

Design of a Wideband Dual-Polarization Full-Corporate Waveguide Feed Antenna Array

“…The losses of the microstrip antennas are mainly caused by the surface wave of antenna elements, feed-line radiation and dielectric loss. To suppress the feed-line radiation and surface wave loss, substrate integrated waveguide (SIW) feed-network and substrate cavity are adopted in [5][6][7][8]. However, the dielectric loss is hard to avoid due to the utilization of dielectric substrates, particularly when the array size is large.…”

A groove gap waveguide iris filter for V-band application

“…However, recently millimeter wave gap waveguide structures have been published as a transmission line [6] and as an antenna [11]. Among all the gap waveguide geometries, the groove gap waveguide structure has TE 10 -type mode propagation, like in rectangular waveguide [12], and has the highest quality factor among the different types of gap waveguides [13].…”