Broadband Printed-Circuit Yagi Array

Printed circuit board (PCB) antenna with useful bandwidth covering from 2.45 GHz to 3.80 GHz is suitable for WiMax, WLAN, and Bluetooth wireless communications applications. We present a low profile, seven elements Yagi array antenna etched on PCB of dielectric constant 4.2 achieving 43% bandwidth with return loss better than -10 dB, and directivity from 8.2 dBi to 11.1 dBi. Swept frequency return loss, impedance and radiation patterns of this antenna have been simulated and measured: The congruence between the simulated and measured results is satisfactory. In addition, current distribution on this broadband Yagi is also investigated.