SIR based Frequency Reconfigurable Antenna using Varactor Diodes

A varactor controlled electronically reconfigurable dipole antenna is presented. The property of a stepped impedance resonator is utilized to achieve the resonant frequency of the dipole antenna. By embedding varactor diodes on the dipole arms and varying the reverse bias voltage, the current flow distribution in the radiating structure can be changed. Experimental results shows that by trimming the varactor diode, a high tuning range of 780 MHz (1.98 GHz-2.76 GHz) is achieved.