Systematic design approach for capacitively coupled microelectromechanical filters

• Published in: IEEE transactions on ultrasonics, ferroelectrics, and frequency control Vol. 53; no. 9; pp. 1662 - 1670
• Main Authors: Alastalo, A.T., Kaajakari, V.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01-09-2006; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Acoustics; Band pass filters; Bandpass filters; Design engineering; Exact sciences and technology; Film bulk acoustic resonators; Filtering theory; Fundamental areas of phenomenology (including applications); General equipment and techniques; Insertion loss; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Intermodulation distortion; Microelectromechanical systems; Micromechanical devices; Performance loss; Physics; Q factor; Resonator filters; Retarding; Specifications; Stopping; Surface acoustic waves; Terminals; Transducers; Ultrasonics, quantum acoustics, and physical effects of sound; Input impedance; Input output; Electromechanical device; Insertion loss; Band pass filter; Portable equipment; Output impedance; Intermodulation; Miniaturization; Microelectromechanical device
• ISSN: 0885-3010; 1525-8955
• DOI: 10.1109/TUFFC.2006.1678194

A design procedure for microelectromechanical (MEMS) band-pass filters is formulated that takes into account specifications set for carrier-to-interference ratio (C/I) and insertion loss. Since suppressing intermodulation distortion to maximize C/I in MEMS filter design typically leads to increased loss and vice versa, it is necessary to aim at a feasible compromise in filter performance that meets all of the requirements. In order to meet specifications that are typical for a handheld communication terminal, an integrated receiver architecture, where filter input and output impedances other than 50 Omega can be used, is found to be more feasible than resistively terminating the front-end filter at source and load to 50 Omega