Ultra-miniature coupled resonator filter with single-layer acoustic coupler

Author

Jamneala, Tiberiu ; Koelle, Uli B. ; Shirakawa, Alexandre ; Gilbert, Stephen R. ; Nikkel, Phil ; Feng, Chris ; Ruby, Rich

Author_Institution

Avago Technol., Inc., San Jose, CA, USA

Volume

56

Issue

11

fYear

2009

fDate

11/1/2009 12:00:00 AM

Firstpage

2553

Lastpage

2558

Abstract

Coupled resonator filters designed using a single-layer coupler require coupling materials with an acoustic impedance less than 5.0 MRayl. Carbon-doped oxide, with an acoustic impedance of 4.8 MRayl and an acoustic attenuation of 200 to 600 dB/cm at 1 GHz, can be used as a single-layer coupler to produce a competitive 2-stage coupled resonator filter for cellular handset applications in the gigahertz frequency range. The electrical response of our filter is superior to that of coupled resonator filters using a traditional acoustic mirror as the coupling element. We present an ultra-miniature 0.58 mm times 0.38 mm coupled resonator filter operating at a frequency of 2.15 GHz.

Keywords

acoustic couplers; acoustic impedance; acoustic resonator filters; acoustic wave absorption; cellular radio; acoustic attenuation; acoustic impedance; acoustic mirror; carbon-doped oxide; cellular handset; coupled resonator filter; electrical response; frequency 2.15 GHz; gigahertz frequency range; single-layer acoustic coupler; Acoustic applications; Acoustic materials; Attenuation; Bandwidth; Electrodes; Impedance; Microwave filters; Resonator filters; Scattering parameters; Tungsten; Acoustics; Computer-Aided Design; Equipment Design; Equipment Failure Analysis; Filtration; Micro-Electrical-Mechanical Systems; Miniaturization; Reproducibility of Results; Sensitivity and Specificity; Transducers;

fLanguage

English

Journal_Title

Ultrasonics, Ferroelectrics, and Frequency Control, IEEE Transactions on

Publisher

ieee

ISSN

0885-3010

Type

jour

DOI

10.1109/TUFFC.2009.1342

Filename

5306735