Recently, the enormous growth in personal communications systems (PCS), satellite communication and various other forms of wireless data communication has made analogue frequency control a key issue with operation frequency increasing to the low/medium GHz range. As the only technology that can be integrated with RFIC and MMIC, FBAR (Film Bulk Acoustic Resonator) is promised to be the best solution among many front-end frequency selection choices, which has much smaller volume, higher working frequency, qua...