Six-beam reconfigurable wire antenna

A novel concept of a beam reconfigurable antenna is presented which rotates the beam of a 2-element Yagi antenna without mechanical rotation. The antenna is based on an arrangement of six wires extending radially from the apex of a support. A switch circuit is used to combine two wires into the driven dipole and two wires into the parasitic dipole. The paper presents the basic Yagi antenna using Inverted-V dipoles with verification of simulations by an experimental model at 1 GHz. A fully configurable array was built for operation at 14 MHz to serve in a short-wave direction finding system. Based on simulation, the antenna provides a gain of about 8 dBi and a front-to-back ratio of 10 to 15 dB. Improvements are expected from the use of horizontal dipoles or folded dipoles and additional radiator types can be configured, like single-dipole or vertical top-loaded radiator antennas. Realizations of the concept seem to be feasible up to the low microwave frequency range by suitable miniaturization of the switching circuit and such reconfigurable antennas may provide diversity gain in communication systems.