Omnidirectional Dual-Polarized Antenna With Sabre-Like Structure

• Published in: IEEE transactions on antennas and propagation Vol. 65; no. 6; pp. 3221 - 3225
• Main Authors: Liu, Peiqin, Li, Yue, Zhang, Zhijun, Feng, Zhenghe
• Format: Journal Article
• Language: English
• Published: New York IEEE 01-06-2017; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Antenna diversity; Antennas; Azimuth; Azimuthal plane; Cavity resonators; Coefficients; Construction; Coplanar waveguides; Design engineering; Dipole antennas; Drag; Dual polarization (waves); Feeding; Holes; Horizontal polarization; hybrid-feeding cavity; Impedance; Impedance matching; Microstrip; omnidirectional patterns; Polarization; Ports; Probes; Reflectance; Reflection; sabre-like structure; Vertical polarization
• ISSN: 0018-926X; 1558-2221
• DOI: 10.1109/TAP.2017.2690534

In this communication, a sabre-like dual-polarized antenna with omnidirectional patterns in the azimuthal plane is presented for low wind drag airborne applications. The proposed antenna consists of a thin cavity for the horizontal polarization and a coplanar waveguidefed monopole for the vertical polarization. The colocated thin cavity and the monopole construct a compact sabre-like structure with low wind drag, and it is suitable for airborne use. Especially, a hybrid-feeding structure, including a capacitive slot-coupled microstrip line and an inductive probe, is proposed for impedance matching of the thin cavity to provide omnidirectionally horizontal polarization. In order to verify the proposed design, a prototype is fabricated and tested with the dimensions of 42 × 29 × 9 mm 3 . (0.42λ 0 × 0.24λ 0 × 0.07λ 0 , λ 0 is the free-space wavelength at 2.44 GHz.) The measured -10 dB reflection coefficient bandwidths of the two ports are 2.38-2.51 and 2.28-2.53 GHz. The measured gain variation in the azimuth plane is less than 3.60 and 3.45 dB for horizontal polarization and vertical polarization.