高频宽带换能器研究

主要研究高频换能器的匹配层技术，通过匹配层技术拓宽换能器的频带，首先利用等效电路法分析高频匹配层换能器，其次通过Matlab仿真分析匹配层材料的密度、声速、厚度变化对换能器电声参数性能的影响，进而对其电声性能进行优化设计，最终制作出一高频宽带换能器。通过实验测得结果与仿真结果基本一致，实验测得换能器的最大发送电压响应为178dB，工作频带为260～370kHz，带内发送电压响应起伏为-3dB，300kHz时换能器指向性-3dB开角为6．5°。

Study of high frequency broadband transducer

This paper mainly investigated the matching layer technique for high frequency transducers. High-frequency transducer with a matching layer was first analyzed with equivalent circuit method. Then, the effect of matching layer parameters on the acoustic transducer performance was summarized by simulation. And its electro-acoustic characte- ristics were optimized. Finally, a high frequency broadband transducer was designed. Experimental results are in agreement with the theoretical values. It was shown that （i） the maximal transmitting sound level can reach 178 dB; （ii） the bandwidth of the transducer is 260-370 kHz; （iii） the fluctuation of the transmitting voltage response is -3 dB; （iv） the transducer has a directional angle of 6.5 degree with -3 dB @ 300kHz.