| 摘要 |
#CMT# #/CMT# The filter (100) has a lamb wave resonator (106) comprising electrodes (102, 103) placed on opposite surfaces of a part (108) of a resonant layer (101). Another Lamb wave resonator (107) has other electrodes (104, 105) placed on opposite surfaces of another part (109) of the resonant layer. One of surfaces of the part (108) belongs to a plane parallel to one of surfaces of the part (109) and passes between the electrodes (104, 105). The resonators are acoustically coupled by a periodic network. #CMT#USE : #/CMT# Filter for channel filtering or intermediate frequency filtering in a multistandard transmitting and receiving architecture e.g. portable communication device, that is utilized for mobile communication based on global system for mobile communication (GSM), general packet radio service (GPRS), Universal Mobile Telecommunications System (UMTS)or wireless local area network (WLAN) or 2/2.5/3rd generation type telephonic standards. #CMT#ADVANTAGE : #/CMT# The utilization of the single resonant layer improves the reliability of the filter and facilitates easy fabrication of the filter. The resonators are acoustically coupled by a periodic network, thus increasing bandwidth of the filter. The filter can be directly integrated on an integrated circuit so as to improve performance of the circuit by reducing loss of filtered signals and by decreasing cost and size of the circuit. #CMT#DESCRIPTION OF DRAWINGS : #/CMT# The drawing shows a perspective view of a filter with Lamb wave resonators. 100 : Filter 101 : Resonant layer 102-105 : Electrodes 106, 107 : Lamb wave resonators 108, 109 : Resonant layer`s parts #CMT#METALLURGY : #/CMT# The resonant layer is made of piezoelectric material such as aluminum nitride, zinc oxide or lead zirconate titanate (PZT). |
