SIW Cavity-Backed MIMO Antenna with Planar Excitation for Ku-Band Applications

In this paper, a fully planar substrate-integrated waveguide (SIW) cavity-backed multiple-input-multiple-output (MIMO) antenna is proposed for Ku-band applications. The complete structure of the proposed MIMO antenna configuration is realized on a single layer of substrate by closely placing two identical SIW cavity-backed slot antenna elements with radiation fields orthogonal to each other. In the proposed antenna, a unique combination of the grounded co-planar waveguide (GCPW) feeding network with SIW cavity-backed slot antennas significantly enhances the MIMO performance while keeping the overall profile simple and small. The proposed antenna exhibits an impedance bandwidth of 6% (14.−15.2 GHz) with isolation and ECC better than 30 dB and 0.00025, respectively, over the entire operating band. Maximum gain of 7.3 dBi is achieved. The other MIMO parameters of the proposed antenna are also well-suited for the design of compact receiver modules for Ku-band very small aperture terminal (VSAT) communication applications.