用于地震观测的瞬态滤波器仿真研究

现代地震数据采集器中广泛使用的最小相位滤波器和线性相位滤波器各有不足之处，最小相位滤波引起的“振铃”尾波，线性相位滤波引起的“前缀”波，无法用后续处理的方法消除。本文提出一种专用于地震波形采集的瞬态滤波器设想，该瞬态滤波器既能满足最小相位特性，又能保持较好的线性相位特性。本文用Matlab设计出了可以满足上述条件的瞬态滤波器，并通过仿真比较了正弦接入波通过3种滤波器的输出波形。从仿真结果可以看出，与最小相位和线性相位滤波相比较，该瞬态滤波器的波形失真最小。

The simulation study of instantaneous filter applied for earthquake observation

Both minimum phase filter and linear phase filter used in data acquisition recorder have demerits. Seismic wave recorded by minimum phase filter has obvious ring trail and recorded by linear phase filter has prefix wave, which can not be eliminated in data process. The idea that instantaneous filter specially designed for seismic wave acquisition is proposed in the paper, which is not only characteristic of minimum phase, but also good linear. Instantaneous filter is designed using Matlab in the paper, and output wave of sine wave throw three filters are compared. It can be seen from simulation results that the instantaneous filter has the minimum distortion compared to minimum phase and linear phase.