Package Optimization of the Cilium-Type MEMS Bionic Vector Hydrophone

We optimize the package of the cilium-type MEMS bionic vector hydrophone introduced by Chenyang and Wendong in 2007, which has the disadvantages of a low receiving sensitivity, narrow frequency band, and fluctuating frequency response curve. Initially, a full parametric analysis of frequency response and sensitivity with different material sound transparent cap were made. Then, we propose and realize an umbrella-type packaged structure with high receiving sensitivity and wide frequency band. The theoretical analysis and simulation analysis are conducted by ANSYS software and LMS virtual. Lab acoustic software. Finally, to verify the practicability of the package, the umbrella-type packaged hydrophone calibration was carried out in the National Defense Underwater Acoustics Calibration Laboratory of China. The test results show that the performance of umbrella-type hydrophone has been greatly improved compared with the previous packaged hydrophone: exhibiting a receiving sensitivity of -178 dB (increasing by 20 dB, 0-dB reference 1 V/μPa), the frequency response ranging from 20 Hz to 2 kHz (broaden one times), the fluctuation of frequency response curve within ±2 dB, and a good dipole directivity.