【作者】 黄勇军；

【导师】 朴胜春；

【作者基本信息】 哈尔滨工程大学 ， 船舶与海洋工程， 2005， 硕士

【摘要】 随着现代水声技术的发展和声纳设备性能的不断改进，对声纳阵元的性能要求正逐步提高。在现代数字化声纳装备中，要求水听器能高保真地采集信号波形。为了满足这一要求，实现波形复现，必须知道水听器阵元的复数灵敏度一相位灵敏度和幅值灵敏度。而常规的三换能器互易法经改进后虽然也能得到水听器的复数灵敏度，但当校准频率达到上千赫兹时，因为不可能完全消除距离因子的影响，使得相位校准的不确定度随着频率的升高而线性增大。本论文研究的内容就是在10～100kHz频率范围内，利用激光多普勒测振技术校准水听器的复数灵敏度，并采耳义相应的措施使校准的不确定度控制在规定范围内，满足实际使用要求。 本论文首先介绍了激光多普勒测量的基本知识，包括多普勒测振仪的原理和构造、激光多普勒测振技术在声学测量中的应用以及水声测量中常用的三种激光测量方法。 进一步的内容则详细地推导了三换能器互易法和激光法校准水听器复数灵敏度的校准公式。并考虑了声光作用下激光干涉仪所检测到的振速量与膜片表面振速之间的关系，并给出了等效折射系数的相幅曲线，为校准数据的修正提供了理论依据。依据校准原理构建了实验系统，确定了各分系统的主要功能，分析了影响校准不确定度的各不确定度分量，并进行了合成标准不确定度和扩展不确定度的计算。 实验是在φ1.2m×1.8m的圆柱型玻璃钢水槽进行的。针对实验中遇到的问题，在实验中采用了一些相应的措施来保证。比如，实验水槽放置在隔振立柱上，利用它来有效地隔除地面的振动；利用专用的膜片支架固定25μm厚度的透声反光膜片，以确保膜片随周围水介质做等幅同相运动；使用具有20倍放大量的光学水准仪，可保证水听器的几何中心和膜片上激光入射点的位置重合；精确控制数字示波器的采样速率，保证波形数据的整周期采样来提高数据分析的精度等等。在实验中，选定两个球形水听器进行校准实验：φ30球(№362)的校准频段为10～50kHz，φ20球(№260)的校准频段为10～100kHz。更多还原

【Abstract】 With the development of the technique of modern underwater acoustics and the improvement of sonar equipment, the requirement for performance of sonar elements is increasing. In modern digital sonar equipment, hydrophones are mainly applied to collect signal waveforms. To achieve this target signals reversion, we should know the plural sensitivity of hydrophone elements — the phase sensitivity and amplitude sensitivity. Although the improved normal three transducers reciprocal method can obtain plural sensitivity, when the calibration frequency comes up to a thousand hertz, it’s impossible to eliminate the influence of distance factor completely, and make the uncertainty of phase calibration increase linearity with frequency. This paper is to study the calibration of the plural sensitivity of hydrophone using laser Doppler vibrometer technology in the frequency range form ten kilohertz to hundred kilohertz, and take steps to make the uncertainty of calibration in the stipulation scope.Firstly, the paper introduces the basic knowledge of laser Doppler measure. It consist of the principle and construct of Doppler vibrometer, the application of Laser Doppler vibrometry technology in the acoustical measurement, and three types laser measurement method commonly used in underwater acoustic.Secondly, it will deduce calibration formula for hydrophone plural sensitivity of three transducers reciprocals method and laser method in detail. And we not only take the relations between vibration velocity measured by laser interferometer and surface velocity of membrane under the acousto-optic function into account, but also offer the phase response and amplitude response curves of equivalent refraction coefficient, now it afford the theory basis for the calibration data revision. Finally, according to the calibration principle, we constructed the experimental system, and analyzed the whole measurement system’s uncertainties.更多还原