Study of a Low-Profile Substrate Integrated Waveguide based Bidirectional Dual-beam Array Antenna

This paper showcases a single-layer, compact substrate-integrated waveguide (SIW) based dual-beam bidirectional array antenna. The SIW is constructed using Rogers-8580 substrate with copper cladding on both sides. One end of the waveguide is fed through a 504$\omega$ microstrip line, while the other end is terminated with metal vias. To get array performance with a bidirectional pattern, some slots are cut strategically from the upper and lower metal walls of the following waveguide. A comparative analysis is conducted between this antenna and a one-sided slotted SIW array. The proposed antenna array radiates in bi-direction, yielding a realized gain of 7.5dBi, fractional bandwidth of 1.5%, and cross-polarization difference (XPD) of 29dB.