A simple planar high-directivity Yagi-Uda antenna with a concave parabolic reflector

A simple planar Yagi-Uda antenna with a single director and a concave parabolic reflector on a thin dielectric substrate is proposed. Through the innovative design, the simple Yagi-Uda antenna can achieve the high directivity of 9.0 dBi, front-to-back ratio of 14.5 dB, cross-polarization level of-38.7 dB, bandwidth of 6.0%, and the radiation efficiency of 85.1%, i.e., better than -1 dBi in terms of the 3D average gain. This proposed antenna is especially suitable for the mobile devices with GPS functions.