2026-07-24 Latest Published
By Qiushou Liu
Kunshan Mo
Jin Wu
Lin Peng
Rui Fang
Progress In Electromagnetics Research C, Vol. 172, 1-6, 2026
Abstract
Wireless communication nodes in the underground mine gob area are often disturbed by different orientations; therefore, antennas with quasi-isotropic radiation are critical for reliable wireless communication. To address this challenge, a compact, cylindrical, conformal, quasi-isotropic antenna operating in the VHF band is proposed. The design integrates a shorted-patch structure with orthogonal dipole radiation, formed by a shorting post and patch aperture, to realize nearly isotropic Radiation. A capacitive-coupling feed is employed to enhance impedance matching, yielding an impedance bandwidth of about 1.02 MHz (S11 < -10 dB) at 170 MHz. The fabricated prototype, with dimensions of 120 mm × 120 mm × 110 mm (0.068λ0 × 0.068λ0 × 0.063λ0), was validated through full-wave simulations and experimental testing. The two results show excellent agreement, demonstrating a measured maximum-minimum gain variation of only 2.74 dB, confirming the antenna's good quasi-isotropic characteristics. Owing to its compact volume, stable matching, and consistent omnidirectional coverage, the proposed antenna is a good candidate for underground mine gob area communication nodes.
