摘要
短时长时能量比法(short-term average/long-term average, STA/LTA)因原理简单、计算简便而被广泛用于地震检测及到时拾取,但传统STA/LTA方法因时窗位置关系,使算法功能被大大弱化,以致拾取精度较低,虚警率较高。为解决上述问题,以STA/LTA为基础对其窗口位置和特征函数两个方面进行改进。首先,基于中间窗的STA/LTA改进法,采用中间窗的形式代替传统时窗位置,能够抑制短时强干扰带来的影响;其次,基于改进特征函数的STA/LTA法,该方法利用信息融合的思想,提出综合考虑地震信号振幅与频率变化信息的权重分配因子来灵活调整权重,实现优势项分配的目的,提高对事件的敏感性。最后,将两种改进方法结合使用并进行实验。结果表明:改进方法能够提高事件检测的灵敏度与到时拾取精度,有效降低虚警率。
The short-term average/long-term average(STA/LTA)method is widely employed in seismic detection and first arrival picking due to its simple principle and calculation.However,the conventional STA/LTA method significantly compromises the algorithm’s effectiveness as a result of the time window position,leading to low accuracy in picking and a high false alarm rate.To solve the above problem,improved methods of window position and feature function of the STA/LTA were proposed.Firstly,an improvement approach was adopted based on utilizing the middle window instead of the traditional position effectively mitigated shortterm strong interference.Secondly,an enhanced feature function was proposed by incorporating information fusion principles to dynamically adjust weights considering factors such as seismic signal amplitude and frequency changes.This enabled advantageous allocation of weights and enhanced sensitivity towards events.Finally,these two improved methods were combined.Yielding experimental results demonstrate that the improved method can enhance the event detection sensitivity and accuracy in time picking,and effective reduction in false alarm rate.
作者
李鸿儒
李夕海
谭笑枫
张云
刘天佑
LI Hong-ru;LI Xi-hai;TAN Xiao-feng;ZHANG Yun;LIU Tian-you(School of Nuclear Engineering,Rocket Force University of Engineering,Xi’an 710025,China)
出处
《科学技术与工程》
北大核心
2024年第24期10165-10173,共9页
Science Technology and Engineering
基金
陕西省自然科学基金面上项目(2023-JC-YB-221)。
关键词
短时长时能量比(STA/LTA)
地震检测
初至拾取
特征函数
信息融合
short-term average/long-term average(STA/LTA)
seismic detection
first arrival pick
characteristic function
information fusion
