Design of an 8-element switched mode circular antenna array for vehicular direction finding

In this work we present the design and fabrication of an 8-element circular printed yagi antenna array that is operated in switched mode for a radio frequency direction finding system in vehicular platforms. The array is designed to operate in the 2.45 GHz frequency band. The directional gain patterns have a HPBW between 65 - 110 degrees in the azimuth plane which will be used to identify the direction of the incoming RF signal from one of 8 sectors. The introduction of ground splits in the ground plane gave a better shaped directional pattern as well as better matching. Simulation and measurement results are shown and compared.