A Compact Self-Multiplexing Antenna for Quadband Applications

A compact lightweight substrate integrated waveguide based self-multiplexing antenna is introduced for quad-band applications. The antenna layout is very simple and straightforward. Top side of the cavity is perturbed to create four different patches which are excited separately by four planar feeds. Upon excitation the antenna operates at 4.61 GHz, 5.34 GHz, 6.03 GHz, and 6.94 GHz with gain values of 4.3 dBi, 3.3 dBi, 3 dBi, and 2.9 dBi respectively. The perturbation topology allows the antenna to redesign each frequency independently over wide range using single parameter. The observed front-to-back ratio stands near 12 dB and isolation is better than 25 dB. The antenna doesn’t require external multiplexing circuitry and saves large space. The overall antenna size is 0.22 ${\lambda _{\text{g}}}^2$ and can be a suitable candidate for quad band applications in compact RF/microwave devices.