Quad-Port Pattern-Diversity Dielectric Resonator Antenna for Intelligent WiFi Applications

This paper presents a quad-port pattern-diversity cross-shaped dielectric resonator (DR) antenna (DRA). The DRA is fed by four feeding strips connected to the outputs of two printed 180° hybrid couplers. A cross-shaped groove is introduced at the bottom of the DR, enabling simultaneous excitations and tuning of two DRA modes to improve the port isolations. Also, a central cylindrical hole is incorporated into the DR to decouple and enhance the antenna gain. The design can simultaneously generate four different radiation patterns (two boresight beams with different polarizations and two orthogonal bi-directional beams). Also, by externally adding a power divider, tilting angles can be introduced to the two boresight radiation beams, forming a new set of radiation patterns for the diversity design. A prototype was fabricated and measured to validate the design. Measured results show that the design has an operating impedance bandwidth of 7.3% (5.71-6.14 GHz), inter-port isolation of 20 dB, and peak antenna gain of 6.439.45 dBi. © 2026 IEEE.