Design of Omnidirectional Dual-Polarized Antenna in Slender and Low-Profile Column

In this communication, a dual-polarized diversity antenna with azimuthally omnidirectional patterns is designed inside a slender and low-profile columnar structure. The proposed antenna is composed of a cavity-backed notch for horizontal polarization and a folded slot for vertical polarization. The most important contribution of this communication is to reduce the antenna dimension, maintain high port isolation, broaden impedance bandwidth, and generate azimuthally omnidirectional radiation patterns. The overall volume of the proposed antenna is 42×12×12 mm³ (0.336λ₀×0.096λ₀×0.096λ₀). A prototype of the proposed antenna is built and measured for 2.4-GHz wireless local area network (WLAN) applications to validate the idea.