Compact six-sector antenna employing patch Yagi-Uda array with common director

A novel compact planar six-sector antenna employing the patch Yagi-Uda array with common directors for mobile terminals is proposed. This antenna has square parasitic director elements that are shared by two sector arrays that face in opposite directions, and has a hexagonal central director element that is shared by all six sectors. These elements form three line arrays, which intersect at 60 degrees to each other. These shared elements enable the sector antenna to be compact. The antenna configuration is described, a numerical analysis of the properties of the front-to-back (F/B) ratio under termination conditions and the number of parasitic elements is given, the validity of the electrical characteristics and the downsizing effect based on the experimental results from a fabricated antenna are shown.