检波器的幅相特性校准方法研究

Research on the Calibration Method of Amplitude-Phase Characteristics of Detectors

摘要: 地震检波器的幅相特性是指其幅频特性和相频特性，它是检波器的重要性能指标，幅频特性决定了检波器采集数据的频带宽度；单个检波器的相频特性反应了检波器响应速度，一批检波器的相位一致性对地震勘探结果有重大影响。因此，检波器的用户和生产商都十分关心该项指标。以前，人们对检波器幅频特性校准研究比较多，在校准时通常也只测试检波器的幅频特性，但随着地震勘探的要求不断提高，相频特性也越来越受到重视。尤其是一批检波器相位的一致性，因为地震勘探时并不是只采用一个检波器，而是用多个检波器组成一个阵列，通过分析这些检波器的信号进行地震勘探。本文研究地震检波器幅相特性的校准方法，尤其是针对相频特性，提出了两种校准方法：一种是基于正弦逼近法的绝对校准法；另一种是通过与标准传感器比较的相对校准法。

Abstract: The amplitude and phase characteristics of a seismic detector refer to its amplitude-frequency and phase-frequency characteristics, which are important performance indicators of the detector. The amplitude-frequency characteristics determine the bandwidth of the data acquired by the detector; the phase-frequency characteristics of a single detector reflect the detector’s response speed, and the phase consistency of a batch of detectors has a significant impact on the seismic exploration results. Therefore, both users and manufacturers of detectors are very concerned about this indicator. Previously, research on the calibration of detector amplitude-frequency characteristics was relatively extensive, and calibration usually only tested the amplitude-frequency characteristics of the detector. However, with the increasing requirements of seismic exploration, phase-frequency characteristics are receiving more and more attention, especially the phase consistency of a batch of detectors, because seismic exploration does not use only one detector, but multiple detectors are arranged into an array, and seismic exploration is carried out by analyzing the signals of these detectors. This paper studies calibration methods for the amplitude and phase characteristics of seismic detectors, especially for phase-frequency characteristics. Two calibration methods are proposed: one is an absolute calibration method based on sinusoidal approximation; the other is a relative calibration method by comparison with a standard sensor.