A compact substrate integrated waveguide backed self-quadruplexing antenna for C-band communication

This article presents a simple, compact, and lightweight substrate integrated waveguide (SIW) backed self-quadruplexing antenna for quad-band applications. The design procedure is straightforward. Topside of the SIW cavity is modified to form four patches of different lengths which are fed separately by four 50-omega microstrip feed lines and operate at 5.14, 5.78, 6.74, and 7.74. It attains 4.1, 4.96, 6.2, and 6.1 peak gain at the above frequencies, respectively. The observed front-to-back-ratio is more than 17.5 dB and the isolation level is above 28 dB. This antenna topology allows to redesign each resonant frequencies as per application requirement using a single parameter and without disturbing other performances. Design guidelines for developing the proposed antenna are provided. A prototype antenna is fabricated using RT-Duroid (5870) substrate and characterized for validation. The proposed antenna is suitable for handheld microwave devices for C-band communication.