Design of multilayer SIW cavity-backed slot antenna array

© 2017 Euraap. In this paper, a multilayer substrate integrated waveguide (SIW) cavity-backed slot antenna array with wideband performance is proposed. In order to broaden the operating bandwidth of SIW slot antenna, multilayer cavities with gradually decreased permittivity and expanded aperture sizes are loaded above the slot, which realizes a smooth transition between SIW slot and free space. A wideband feeding network employing slot coupling is designed to excite the array elements. Results indicate the proposed array operates with 28.4% bandwidth ranging from 22.4 to 29.8 GHz. Besides, stable broadside radiation patterns are obtained across the operating band