低损耗梳状声表面波延迟线的耦合模分析  

Analysis of Low Loss and Comb SAW Delay Lines by Coupling of Modes

作　　者：王文[1] 何世堂[1] 

机构地区：[1]中国科学院声学研究所,北京100080

出　　处：《压电与声光》2006年第1期10-13,共4页Piezoelectrics & Acoustooptics

基　　金：国家自然科学基金资助项目(10374100)

摘　　要：梳状换能器可看成若干叉指单元电端并联,声端首尾串联而成的网络,采用单向结构可降低采用这种结构的声表面波延迟线的损耗。根据耦合模(COM)理论推导出整个换能器的混合矩阵(P矩阵)并结合等效电路模型得到了整个延迟线二端网络的导纳矩阵以及延迟线的幅频及相频响应。本方法能模拟指间反射、三次行程、指条寄生阻抗以及外围电路对器件的影响;理论模拟与实验结构吻合。The comb transducer can be considered as the network of the parallel connection of some units of IDT electrical ports and the series connection of their acoustic ports. Then, in order to reduce the loss, the SPUDT was used to the SAW Delay Lines with the comb transducer. Based on the Coupling of Modes （COM） and equivalent circuit model, the mixed matrix （P matrix） of the transducers and the inductance matrix of the two-port delay line network can be deduced, at last, the response of the delay lines can be acquired. As a result, the internal reflection within IDTs, triple transit echo, parasite impedance of finger, and peripheral circuits can be considered in this method. A typical filter is analyzed numerically and the theoretical simulation is found to agree with the experimental.

关 键 词：梳状换能器 声表面波延迟线 单向结构 耦合模模型 

分 类 号：O426.9[理学—声学]