Frequency tunable microstrip patch antenna using ferroelectric thin film varactor

A novel frequency tunable microstrip patch antenna using ferroelectric BST thin film varactor is presented. The resonant frequency of this reconfigurable antenna is controlled by tuning the capacitance of the RF varactor which is used as part of the antenna feedline in this design. Since the varactor uses the coplanar waveguide (CPW) transmission line, tapered microstrip line between the antenna and the varactor are employed to ensure proper transitions. Experimental results demonstrate that a high tuning range can be achieved for the reconfigured microstrip patch antenna with a lower variation of the DC biasing voltage applied on the ferroelectric varactor.