| 摘要 |
#CMT# #/CMT# The filter (100) has an acoustic resonator (108) comprising a resonant layer (110) that is placed between electrodes (112, 114). An acoustic resonator (118) comprises a resonant layer (120) that is placed between electrodes (122, 124), where the resonator (118) is acoustically coupled with the resonator (108). One of the electrodes (114, 122) is placed between the layers (110, 120), where the layers are made of an electrostrictive material. An acoustic insulation unit (104) is provided such that the resonator (108) is placed between the resonator (118) and the unit (104). #CMT# : #/CMT# An independent claim is also included for a signal transmission and/or reception device comprising an antenna connected to a switchable filter. #CMT#USE : #/CMT# Switchable filter for being connected to an antenna of a signal transmission and/or reception device (claimed) that implements a communication according to second generation, 2.5 generation and third generation type mobile telephony standards. #CMT#ADVANTAGE : #/CMT# The electrodes and the acoustic resonators are arranged such that a DC control voltage can be applied between the electrodes and the acoustic resonators, thus permitting to adjust resonance of the resonators. The resonators can be coupled such that the signal transmission and/or reception device performs filtering and switching functions by the resonant layers made of electrostrictive material, thus reducing size required for integration of the functions in the device. The combination of filtering and switching functions reduces insertion losses between the antenna and data processing unit of the device, while simplifying implementation of the functions. #CMT#DESCRIPTION OF DRAWINGS : #/CMT# The drawing shows a schematic view of a switchable filter. 100 : Switchable filter 104 : Acoustic insulation unit 108, 118 : Acoustic resonators 110, 120 : Resonant layers 112, 114, 122, 124 : Electrodes. |
