超宽带声表面波滤波器的设计  

Design of Ultra-Wideband Surface Acoustic Wave Filters

作　　者：陈景[1] 韩韬[1] 吉小军[1] 唐供宾 张巧珍[1] 

机构地区：[1]上海交通大学仪器科学与工程系,上海200240

出　　处：《压电与声光》2016年第3期353-355,共3页Piezoelectrics & Acoustooptics

基　　金：国家自然科学基金资助项目(11404209);上海自然科学基金资助项目(14ZR1422000);高等学校博士学科点专项科研基金资助项目(20130073120039);教育部留学回国人员启动基金资助项目(教外司留【2014】1685号)

摘　　要：该文精确模拟了基于弛豫铁电单晶的声表面波(SAW)梯形滤波器的性能。首先介绍了由谐振器构成的梯形SAW滤波器的工作原理,利用QUCS软件建立了七阶梯形滤波器的仿真模型。结果表明,该单晶能实现高达620 MHz的超宽带SAW滤波器(中心频率1GHz),比传统压电材料的滤波器带宽高3倍;通过优化各支路谐振器的静态电容及传统梯型滤波器的结构,牺牲了一定的带宽,但获得了较高的带外抑制和过渡带的陡峭度;讨论了不同品质因数对滤波器带内插损的影响。This paper accurately simulated the properties of ladder-type surface acoustic wave（SAW）filters composed of resonators employing relaxor-based ferroelectric single crystals.Firstly,the working principles of ladder-type SAW filter was introduced,and then a simulation model of seven stepped filter was established by utilizing the quite universal simulator（QUCS）.The simulated results showed that an extremely large wideband SAW filter of 620 MHz at 1GHz could be obtained by utilizing such new single crystals,which is presently three times larger than that of the conventional piezoelectric material;the band rejection and skirt steepness could be improved by adjusting static capacitance ratio and modification of the conventional ladder-type filter,but sacrifices some bandwidth;the influence of qullity factor on the insertion loss of SAW filters was discussed finally.

关 键 词：超宽带滤波器 声表面波(SAW) 弛豫铁电单晶 机电耦合系数 品质因数 

分 类 号：TN65[电子电信—电路与系统] TM221[一般工业技术—材料科学与工程]