A Compact Self-Hexaplexing Antenna Implemented on Substrate-Integrated Rectangular Cavity for Hexa-Band Applications

This brief introduces a novel architecture of a compact self-hexaplexing antenna (SHA) implemented on a substrate-integrated rectangular cavity (SIRC) for hexa-band applications. The proposed SHA is configured by using an SIRC resonator, two Pi-shaped slots (PSSs), and six
$50\Omega $
microstrip feedlines. The PSSs are connected back-to-back and loaded on top of the SIRC resonator to produce six patch radiators (PRs). The PRs are excited by
$50\Omega $
feedlines to radiate at six operating bands with self-multiplexing characteristics. The operating bands are tunable. A particular band can be adjusted independently based on the system requirement without altering the other operating bands. A comprehensive parametric study is carried out to allow a suitable band tunability, high isolation, and matching at the ports. For validation, an SIRC-based SHA radiating at 2.29, 2.96, 4.3, 5.0, 5.61, and 6.18 GHz is fabricated and experimentally demonstrated. The proposed SHA allows us to achieve a compact size of
$0.173\lambda _{g}^{2}$
, which is the smallest among the self-quadruplexing antennas and self-multiplexing antennas reported in the literature thus far. Additionally, it exhibits high isolation of 27 dB, hexa-band operation, a tunability range from 2.2 GHz to 8 GHz, along with measured gains greater than 3.73 dBi.