精确测定地震计传递函数

提出联合阶跃标定与带精确电流测量的正弦波标定来确定地震计传递函数的方法。首先，使用阶跃标定确定地震计等效机械摆的自振周期和阻尼，得到地震计低频特性。随后，使用正弦波标定并引入电流测试技术，测定地震计全频段频率响应，幅频响应更加准确，同时可获得相频响应。最后，构建与地震计传递函数特征一致的结构来描述传递函数，采用最优化方法拟合求取地震计传递函数。该方法具有原理清楚、操作简单、易于实现、结果精确等优点，特别适用于地震计用户测试、地震计传递特性与厂方参数及各地震计间一致性和长期稳定性的验证，结果符合反馈型地震计传递函数特点。

Precise determination of transfer function for feedback seismometer

A precise determination method of transfer function for a feedback seismometer with step and sine signal calibration is given in this paper. Firstly its natural period and damping rate is measured by step calibration, so the low frequency part of the transfer function is gotten. Then the full frequency band of response of the seismometer is calculated from online current measured sine signal calibration data. The transfer function of the seismometer is from fitting of the full frequency band of response with a model in accordance with intrinsic structure of the transfer function of a feedback seismometer. This method is special suitable to verification of transfer function, on site measurement of transfer function to know the long time stability of a seismometer.