本标准规定了校准水下电声传感器的测量程序。这是对美国国家标准S1的修订。20-1988（R2003）。对于从几赫兹到几兆赫的频率，规定了主要和次要校准程序。规定了确定自由场接收电压灵敏度、发射响应、方向响应、电压耦合损耗、阻抗和等效噪声压力的可测量特性的程序。介绍了这些测量类型的测量不确定度分析，以及常见误差源的识别。给出了以下导出特性的方程:波束图、方向性因子和折射率、等效双向波束宽度、声功率输出和电平、电功率输入、传输效率、开路有效带宽和质量因子。附件包括以下内容: A） 在实验室储罐中进行自由场校准，B）介质校正系数，C）测量灵敏度和响应？次声和低音频范围，D）通过互易法获得的自由场电压灵敏度相位，E）包括空化在内的非线性效应，以及F）校准主动声纳的标准目标方法。

This standard establishes measurement procedures for calibrating underwater electroacoustic transducers. It is a revision of American National Standard S1.20-1988 (R2003). Both primary and secondary calibration procedures are specified for frequencies from a few hertz to a few megahertz. Procedures are specified for determining the measurable characteristics of free-field receive voltage sensitivity, transmitting response, directional response, voltage coupling loss, impedance, and equivalent noise pressure. Measurement uncertainty analysis is introduced for these measurement types, with identification of common error sources. Equations are given for the following derived characteristics: beam pattern, directivity factor and index, equivalent two-way beam width, acoustic power output and level, electrical power input, transmitting efficiency, open-circuit effective bandwidth, and quality factor. Annexes have been included to address: A) free-field calibration in a laboratory tank, B) medium correction factors, C) measurement of sensitivity and response?infrasonic and low audio-frequency range, D) phase of free-field voltage sensitivity via reciprocity method, E) nonlinear effects including cavitation, and F) standard-target method for calibrating active sonars.