A Cavity-Based Self-Quadruplexing Antenna for C-Band Communications

This paper introduces a self-quadruplexing antenna (SQA) comprising four ports, with a Swastik slot etched out at the top surface. The antenna incorporates four 50 Ω insert feedlines and features a substrate-integrated square cavity (SISC) structure. With corresponding gains of 3.3 dBi, 5.25 dBi, 4.37 dBi, and 4.53 dBi, the suggested antenna operates at 4.49 GHz, 4.91 GHz, 5.32 GHz, and 6.09 GHz. The mutual coupling among the ports exceeds 22.35 dB, and the compact design of the prototype renders it suitable for wireless communication.