水声声压是声学测量中应用最广泛的参数,声学计量检定系统中对水听器声压灵敏度的校准有多种方法。传统的水声测试系统使用工业计算机及水声水池,体积相对庞大。伴随着新型器件、新材料和数据采集器的应用,利用比较法校准原理及声波导管理论,以嵌入式系统为核心,设计一种能够在普通密闭腔体内完成测试的便携式水听器测试仪。可以进行直流电阻、交流阻抗、灵敏度、极性测量,且具有扫频及自动校准功能,软件界面友好。对密闭声场的仿真及实测结果表明,该仪器测量以密闭声场代替水声水池,电压测量精度为0.5 mV,电压灵敏度级的测量精度高于0.8 dB,满足产品生产测试要求,应用前景良好。
Acoustic pressure parameter is widely used in acoustic measure system,there is a variety of methods to calibrate sensitivity of hydrophone pressure in acoustic verification system.The traditional acoustic testing system using industrial computer and relatively large volume of water pool.With new devices and materials,embedded system as the core,based on the comparison principle and acoustic wave calibration theory,we design a portable hydrophone instrument,which can work in ordinary airtight cavity including dc resistance,ac impedance,sensitivity,polarity,sweeping frequency measurement and auto-calibration function with friendly user interface.The simulation of acoustic field in airtight cavity and measured results show that,the instruments with airtight cavity instead of acoustic field of pool,the accuracy of voltage is 0.5 mV,the accuracy of voltage sensitivity level is better than 0.8 dB,satisfying test requirements of production and the application prospect is good.