A Wide-Band Planar Dipole Antenna with Switched Beam

This paper presents a design of a half wavelength dipole antenna with beam-switching property. The arms of the dipole antenna have a rotation angle of 30°, and the antenna is fed with a bent microstrip line. A tapered microstrip balun is adopted for impedance matching. PIN diodes are incorporated on both arms, and hence beam-switching property can be achieved by controlling the states of diodes. The beam tilting angle is approximately ± 20 ° • The antenna operates in a wide band from 3.1 GHz to 4.1 GHz.