第46卷第1期压电与声光Vol.46No.12024年2月PIEZOELECTRICS&ACOUSTOOPTICSFeb.2024收稿日期:2023-09-11作者简介:王巍(1967-),男,湖南省邵阳市人,教授,硕士生导师,博士。文章编号:1004-2474(2024)01-0001-05DOI:10.11977/j.issn.1004-2474.2024.01.001基于漏纵波模式的高频宽带低插损滤波器设计王巍,张迎,王方,滕洪菠,丁辉,郭家成,吴浩(重庆邮电大学光电工程学院/国际半导体学院,重庆400065)摘要:采用常规的瑞利声表面波设计低插损、大带宽的高频声表滤波器,难以满足设计要求。该文设计了一种基于多层膜结构的漏纵波(LLSAW)的高频宽带低损耗声表面波(SAW)滤波器。确定了激发LLSAW的波导结构,建立器件的二维理论模型;研究了电极各项参数对杂散的影响,在此基础上对电极参数进行了优化设计。研究发现,将串联谐振器的反射栅对数设置为6时,可有效抑制通带内的杂散。设计了镜像T型及镜像π型LLSAW结构滤波器,并进行性能比较分析。结果表明,镜像T型结构更能抑制杂散响应,设计的镜像T型结构LLSAW滤波器的中心频率为3545MHz,插入损耗为-1.416dB,-3dB带宽为274MHz,带外抑制大于-30dB。关键词:漏纵波;电极;反射栅;杂散响应;镜像T型中图分类号:TN65;TN713文献标识码:ADesignofHighFrequencyBroadbandLowInsertionLossFilterBasedonLongitudinalLeakyWaveWANGWei,ZHANGYing,WANGFang,TENGHongbo,DINGHui,GUOJiacheng,WUHao(SchoolofOptoelectronicsEngineering/InternationalSemiconductorCollege,ChongqingUniversityofPostsandTelecommunications,Chongqing400065,China)Abstract:Itisdifficulttomeetthedesignrequirementsofhigh-frequencysurfaceacousticwave(SAW)filterswithlowinsertionlossandlargebandwidthusingconventionalRayleighsurfaceacousticwavedesign.Inthispaper,ahigh-frequencybroadbandlowinsertionlosslongitudinalleakysurfaceacousticwave(LLSAW)filterbasedonmulti-layerfilmstructurehasbeendesigned.Firstly,thewaveguidestructureexcitingthelongitudeleakysurfacea-cousticwave(LLSAW)isdetermined,andthe2Dtheoreticalmodelofthedeviceisestablished.Secondly,thein-fluencesofvariouselectrodeparametersonthespuriousarestudied.Itisfoundthatwhenthegratingreflectoroftheseriesresonatorissetto6,thespuriousinthepassbandcanbesuppressedasmuchaspossible.Finally,themirrorT-typeandmirrorπ-typefiltersaredesigned,andthep...
