叉指对数对阶梯形叉指换能器的频响特性研究

摘要

The ladder-shaped interdigital transducer (IDT) offers many of the advantages, such as high response frequency and simple design. In order to design flexibly a ladder-shaped IDT in the practical applications, the effect of finger pairs on ladder-shaped IDT is studied for the first time, it is modeled by the improved S function model and simulated by Matlab. The analysis shows that the main peak curve is getting better and sidelobe suppression is larger with the increase the proportion of ladder-shaped IDT in the whole IDT. Therefore, the result is significant and has practical significance in the design of high-performance surface acoustic wave (SAW) device.%阶梯形叉指换能器具有频响性能好,设计简单等特点,为了能在实际应用中对阶梯形叉指换能器进行灵活设计,首次采用改进的δ函数模型对阶梯型叉指换能器进行建模,并通过Matlab软件进行仿真分析,研究了叉指对数对阶梯形叉指换能器频响特性的影响.分析结果表明,阶梯形结构在叉指换能器中所占比例越大,叉指换能器的主峰曲线越好,旁瓣抑制程度也越好.该研究结果对高性能声表面波器件的设计研究具有很强的实用意义.