UHF bent-slot antenna system for portable equipment—I

A newly developed bent-slot antenna for UHF portable communication equipment is introduced. The bent-slot antenna, modified from a half-wave slot element, is designed to have both vertical and horizontal elements and is intended to achieve the improvement of the receiving performance in the urban area. The antenna system characteristics such as current distribution, radiation pattern, gain, and input impedance are investigated both theoretically and experimentally for such parameters as the slot location, the feed point and the width and height of the equipment box. In the calculation, the equipment box is assumed as a rectangular conducting box, and the surface of the box and the slot are modeled by wire grids. The method of moments is applied to find both the electric and magnetic current distributions on wires.