A Ultra-wide Band Half-wavelength Loop Antenna using Self-complementary Principle for UAV Applications

In this paper, we present a low-profile ultra-wide band half-wavelength loop antenna for UAV (Unmanned Aerial Vehicle) applications. The proposed antenna has an ultra-wide band using self-complementary principle. Also, the ground was located between radiators for reducing height of the antenna using image theory. Dimensions of proposed antenna have 0.20λL × 0.14λL × 0.16λL (λL is the free-space wavelength at lowest frequency). Measured ?10 dB bandwidth was ultra-wide band as more than 50 : 1(over 0.3 GHz ~ 15 GHz). The radiation patterns of the antenna was omnidirectional like monopole antennas. Moreover, we tried the antenna mounted on under a fuselage of a scaled UAV. As a result, the proposed antenna on the UAV maintained ultra-wide band and omnidirectional radiation patterns at all frequencies.