A Novel Compact Omnidirectional Tubby Patch Antenna with Capacitive Loading for Stable Radiation in Aero Vehicle Wireless Communications

This paper presents a novel design of an omnidirectional tubby patch antenna for aero vehicle wireless communications and positioning applications. The proposed antenna employs a unique two-layer patch structure surrounding a metallic cylinder, with the inner patch introducing parasitic capacitance near the feed points to achieve antenna size reduction. The antenna is fed at four evenly distributed points by a conventional network. The measured results show that the antenna achieves an impedance bandwidth of 5.1% (1.53 ~ 1.61GHz) and an omnidirectional radiation pattern in the cross-section plane of the cylinder with a gain variation of less than 0.2dB. The antenna size in the resonance direction is approximately 0.11λ (free space wavelength), demonstrating its compact nature. The proposed antenna design offers a promising solution for stable receiving in aero vehicle wireless communications and positioning systems.