A Triband SIW Cavity-Backed Differentially Fed Dual-Polarized Slot Antenna for WiFi/5G Applications

A tri-band differentially fed dual-polarized slot (DFDPS) antenna is developed for indoor WiFi/5G wireless communications. The triband antenna is made up of two crossed slots with four pairs of L-shaped slots. The lower and higher bands are generated by the crossed slots, and the middle band is attributed to the L-shaped slots. Eight shorting pins are introduced for improving the impedance matching for all the three bands. A substrate-integrated waveguide (SIW) cavity is employed to back the antenna for unidirectional radiation. Two orthogonal feedlines are applied to differentially feed the antenna for dual polarization. The antenna has a low-profile of about 0.054 λ
_2.4
, where λ
_2.4
is the wavelength at the lowest frequency of 2.4 GHz in free space. It is shown that the triband antenna can operate in three bands of 2.4-2.51, 3.29-3.6, and 4.8-5.05 GHz with good unidirectional patterns.