In this paper we present the design and fabrication of an RF MEMS tunable band-pass filter. The band-pass filter design uses both distributed transmission lines and RF MEMS capacitances together to replace the lumped elements. The use of RF MEMS variable capacitances gives the flexibility of tuning both the centre frequency and the band-width of the band-pass filter. A prototype of the tunable band-pass filter is realized using parallel plate capacitances. The variable shunt and series capacitances are formed by a combination of parallel plate RF MEMS shunt bridges and series cantilevers. The filter operates at C-X band. The measurement results agree well with the simulation results.
2. Afrang, S. and E. Abbaspour-Sani, "A low voltage MEMS structure for RF capacitive switches," Progress In Electromagnetics Research, Vol. 65, 157-167, 2006.
doi:10.2528/PIER06093001
3. Abbaspour-Sani, E., N. Nasirzadeh, and G. R. Dadashzadeh, "Two novel structures for tunable MEMS capacitors with RF applications," Progress In Electromagnetics Research, Vol. 68, 169-183, 2007.
doi:10.2528/PIER06081404
4. Topalli, K., M. Unlu, H. I. Atadoy, S. Demir, O. Aydin Civi, and T. Akin, "Empirical formulation of bridge inductance in inductively tuned RF MEMS shunt switches," Progress In Electromagnetics Research, Vol. 97, 343-356, 2009.
doi:10.2528/PIER09092502
5. Liu, Y., A. Borgioli, A. S. Nagra, and R. A. York, "Distributed MEMS transmission line for tunable filter applications," Int. J. RF and Microwave CAE, Vol. 11, 254-260, John Willey & Sons, Inc., 2001.
6. Tamijani, A. A., L. Dussopt, and G. M. Rebeiz, "Miniature and tunable filters using MEMS capacitors," IEEE Transaction on Microwave Theory and Technique, Vol. 51, No. 7, 1878-1885, Jul. 2003.
doi:10.1109/TMTT.2003.814317
7. Peroulis, D., S. Pacheco, K. Sarabandi, and L. P. B. Katehi, "Tunable lumped components with applications to reconfigurable MEMS filters ," IEEE MTT-S Digest, Vol. 1, 341-344, May 20-25, 2001.
8. Lee, S., J. Kim, J. Kim, Y. Kim, and Y. Kwon, "Millimeter-wave MEMS tunable low pass filter with reconfigurable series inductor and capacitive shunt switches," IEEE Microwave and Wireless Components Letters, Vol. 15, No. 10, 691-693, Oct. 2005.
9. Park, J., S. Lee, J. Kim, H. Kim, Y. Kim, and Y. Kwon, "Reconfigurable millimeter-wave filters using CPW-based periodic structures with novel multiple-contact MEMS switches," IEEE Journal of Microelectromechanical Systems, Vol. 14, No. 3, 456-463, Jun. 2005.
doi:10.1109/JMEMS.2005.844849
10. Saha, S. C. and T. Sæther, "Modeling and simulation of low pass filter using RF MEMS capacitance and transmission line," Proceeding IMAPS Nordic, 155-159, 2005.
11. Saha, S. C., U. Hanke, and T. Sæther, "Modeling, design and simulation of tunable band-pass filter using RF MEMS capacitance and transmission line," SPIE International Symposium, Microelectronics, MEMS and Nanotechnology, Proc. of SPIE, Vol. 6035, Brisbane, Australia, Dec. 2005.
12. Rebeiz, G. M., RF MEMS Theory, Design, and Technology, 92, John Willey & Sons, 2003.
13. Pozar, D. M., Microwave Engineering, 2nd Ed., Vol. 8, John Willey & Sons, 1998.
14. Chiou, Y.-C. and J.-T. Kuo, "Planar multiband bandpass filter with multimode stepped-impedance resonators," Progress In Electromagnetics Research, Vol. 114, 129-144, 2011.
15. Advance Design Systems (ADS) from Agilent.
16. Saha, S. C., H. Sagberg, E. Poppe, G. U. Jensen, T. A. Fjeldly, and T. Sæther, "Tuning of resist slope with hardbaking parameters and release methods of extra hard photoresist for RF MEMS switches," Journal of Sensor and Actuators A: Phys., Vol. 142, 452-461, 2008.
doi:10.1016/j.sna.2007.10.067
17. Saha, S. C., H. Sagberg, E. Poppe, G. U. Jensen, and T. Sæther, "Metallization scheme and release methods for fabrication of RF MEMS switches," Proceedings of 33rd Micro- and Nano-Engineering Conference (MNE 2007), Copenhagen, Denmark, Sep. 2007.
18. Entesari, K. and G. M. Rebeiz, "A differential 4-bit 6.5-10 GHz RF MEMS tunable filter," IEEE Transaction of Microwave Theory and Techniques, Vol. 53, No. 3, Part 2, 1103-1110, 2005.
19. Matthaei, G. L., E. Young, and E. M. T. Jones, "Microwave Filters, Impedance-Matching Networks, and Coupling Structures," Artech House, Norwood, MA, 1980.
20. Pillans, B., A. Malczewski, R. Allison, and J. Brank, "6-15 GHz RF MEMS tunable filters," IEEE MTT-S, 919-922, 2005.
Submit
