Design and analysis of multi‐layer SIW coupler to use in phased array antenna feed network

Abstract

AbstractIn this paper, a directional coupler is designed using the substrate integrated waveguide (SIW) method. The SIW coupler consists of a double‐layer with transverse rectangular slots in the middle of two layers. The proposed coupler contains three ports. The placement of ports is considered based on the generalization of the power divider network. Each layer is printed on 0.508 mm Rogers RT/Duroid 5880 ( and ). The coupling level is basically controlled by the number and size of the slots. This coupling ratio changes from −5 dB to −13 dB. It is complicated to design a single‐layer feed network for a two‐dimensional phased array antenna. The designed SIW coupler can be easily generalized to the feed network for a 2D phased array antenna that consists of a large number of antenna and phase shifter elements. The SIW coupler is simulated using CST software. The results of the analyses, simulations and experiments indicate good performances of the designed coupler.