声表面波质量传感器的P矩阵模型与实验分析  

P-matrix model and experimental analysis of surface acoustic wave mass sensor

作　　者：杨莺[1] 朱大中[1] 

机构地区：[1]浙江大学信息与电子工程学系,浙江杭州310027

出　　处：《浙江大学学报（工学版）》2007年第6期881-885,共5页Journal of Zhejiang University：Engineering Science

基　　金：国家自然科学基金资助项目(60176027)

摘　　要：分析了新结构Y型双声路声表面波(SAW)质量传感器的频域特性.应用P矩阵理论计算结合实验验证,比较了3种不同结构器件的性能.结果表明,换能器孔径加权设计相比均匀孔径设计,有利于减小三、五次回波,旁瓣抑制增加了15 dB,在振荡模式下等效Q值由4 800提高到8 689,短期频率稳定度提高了-1.81 dBc/Hz;倾斜反射栅设计使边缘反射虚假信号减小了约2 dB,在振荡模式下等效Q值由8 689提高到12 477,短期频率稳定度提高了-1.20 dBc/Hz.采用倾斜反射栅与孔径加权设计结构,有利于提高质量传感器在振荡模式下的等效Q值,并提高短期频率稳定度.The frequency domain properties of Y type dual path surface acoustic wave （SAW） mass sensors with new structures were investigated experimentally and theoretically using P-matrix calculation model. The performance of three devices with different structures was compared. By using apodized interdigital transducer （IDT） compared with uniformed IDT, the triple transverse interference （TTI） and multiple reflections were decreased, the side lobe rejection was increased by 15 dB, the equivalent Q value was improved from 4 800 to 8 689 in oscillation mode, and the short term frequency stability was increased by -1.81 dBc/Hz. By using slanting reflector, the bandpass ripple due to edge reflection was reduced by 2 dB, the equivalent Q value was improved from 8 689 to 12 477 in oscillation mode, and the short term frequency stability was increased by - 1.20 dBc/Hz. Therefore, higher equivalent Q value and better short term frequency stability are readily achievable using slanting reflector and apodized IDT in oscillation mode.

关 键 词：Q值 声表面波传感器 变迹加权 P矩阵 反射栅 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置] TN65[自动化与计算机技术—控制科学与工程]