Wideband and High-Sensitivity 1D PMUT Array Transducers

The aim of this study is to explore ways to simultaneously achieve both broadband and high sensitivity for PMUT array transducers. To compensate for the reduced sensitivity caused by increased bandwidth, we devised a method to switch the electrical connections between multiple PMUTs within the same array element during transmission and reception. We prototyped a 64 channel 1D PMUT array transducer with different wiring configurations between PMUTs. The transducer includes array elements with two types of connection configurations α and β. In experiment, the transmitter and receiver array elements were switched in combination to measure round-trip loop gain in water. As a result, the loop gain increased by 4.3 dB when selecting the α-type element for transmission and the β-type element for reception compared to the conventional approach of using the same α-type element for both transmission and reception. We confirmed that the concept of improving sensitivity by switching the wiring configurations between PMUTs is reasonable.