A Miniaturized Cavity-Backed Sector Antenna with Bandwidth Enhancement for UAV Applications

A novel miniaturized cavity-backed sector antenna with bandwidth enhancement for VHF (Very High Frequency) applications is proposed in this paper. The proposed antenna is composed of two symmetrical meandering lines, a planar double-sector patch and a V-shaped backed-cavity. Two symmetrical meandering lines are used to achieve size reduction by connecting four ends of the double-sector patch. Moreover, a V-shaped backed-cavity is employed to improve directivity and achieve better gain. The proposed has a very compact size of ${36}\text{cm}\times {40}\text{cm}\times {25}\text{cm}\ ({0.13\lambda_{0}}\times {0.15\lambda_{0}}\times {0.09\lambda_{0}})$, which could bring considerable benefits for the design of UAV system. Simulated results show that the antenna achieves a return loss better than 10dB over 31% impedance bandwidth. The gain of this antenna is more than 2dBi. With features such as small size, wide bandwidth and good directivity, the proposed antenna can meet the demanding requirements to the application of UAV airborne system.