A compact Yagi-Uda antenna with a transmission line loaded for an ITS in-vehicle terminal in the UHF band

Abstract

Abstract:We propose a three-element Yagi-Uda antenna with an inter-element spacing of 0.025 wavelengths for intelligent transport systems (ITS) in the ultra-high frequency (UHF) band. The Yagi-Uda antenna has a reflector dipole with a transmission line at the center. We show by numerical simulation that the antenna can be placed at the contact limit of a vehicle body with improved performance when the transmission line has a meandering configuration. Further, we show by experiment that the actual gain improves by approximately 2 dB when the antenna is placed near a conducting plate.