高斯牛顿迭代法在地震计传递函数计算中的应用

Applying of Gauss-Newton Iteration Method to the Calculation for the Transfer Function of Seismometer

介绍了利用地震计对阶跃电流标定或稳态正弦电流标定的响应波形获取地震计传递函数的方法。对阶跃标定电流的响应波形进行傅立叶变换(FFT)和扣除阶跃信号频谱的运算获得地震计的幅频特性;从稳态正弦标定电流的响应波形可直接提取幅频特性,然后用高斯牛顿迭代法拟合出地震计传递函数的各个系数。该方法的最大优点是只需要已知幅频特性或其有限离散点的数值就可以拟合出地震计的传递函数,较目前常用的需要同时已知幅频和相频特性的拟合方法更为方便和实用。

We use the response waveform from the calibrating with step or steady sine current to calculate the transfer function of a seismometer. First apply Fourier Transform to the step calibration response waveform and then deduct the frequency spectrum. We obtain the frequency spectrum characteristic of a seismometer from the signal with stead sine calibration current and then use the Gauss- Newton iteration method to fit the several factors of the transfer function of the seismometer. This method only requires to know the frequency spectrum characteristic of a seismometer and to have the point values with finite discrete amplitude, So it is more convenient than the method that not only needs frequency response but also the phase response commonly in present use.