Substrate Integrated Evanescent-Mode Cavity Filter With a 3.5 to 1 Tuning Ratio

In this letter, the design and RF packaging of substrate integrated widely tunable filter is presented. The filter consists of two heavily loaded evanescent-mode cavities embedded into the substrate. The filter is actuated using two piezoelectric discs, which move thin, flexible membranes that form the top of the cavities. To demonstrate the wide tuning a filter is fabricated and measured to cover a very wide frequency range from 0.98 to 3.48 GHz (tuning ratio-3.55:1). The measured insertion loss is less than 3.57 dB for a 1.1% fractional bandwidth filter.

[1]  Jr. R. Wyndrum.  Microwave filters, impedance-matching networks, and coupling structures , 1965 .

[2]  José M. García,et al.  A novel approach to improve the performance of interconnection networks with hot-spots , 1996, Proceedings of EUROMICRO 96. 22nd Euromicro Conference. Beyond 2000: Hardware and Software Design Strategies.

[3]  R. Berezdivin,et al.  Next-generation wireless communications concepts and technologies , 2002, IEEE Commun. Mag..

[4]  Laurent Dussopt,et al.  Miniature and tunable filters using MEMS capacitors , 2003 .

[5]  M.B. Steer,et al.  An electronically tunable microstrip bandpass filter using thin-film Barium-Strontium-Titanate (BST) varactors , 2005, IEEE Transactions on Microwave Theory and Techniques.

[6]  R. Maenner,et al.  Wide piezoelectric tuning of ltcc bandpass filters , 2005, IEEE MTT-S International Microwave Symposium Digest, 2005..

[7]  H. Joshi,et al.  Highly Loaded Evanescent Cavities for Widely Tunable High-Q Filters , 2007, 2007 IEEE/MTT-S International Microwave Symposium.

[8]  H. Joshi,et al.  High Q narrow-band tunable filters with controllable bandwidth , 2009, 2009 IEEE MTT-S International Microwave Symposium Digest.

[9]  W.J. Chappell,et al.  High-$Q$ Fully Reconfigurable Tunable Bandpass Filters , 2009, IEEE Transactions on Microwave Theory and Techniques.