Extraction Of Characteristic Parameters Of Underground Source Signals Based On F-K Analysis

Underground shallow source localization is a new area of seismic positioning extension,and it is the primary problem that needs to be solved in the research of realizing the evaluation of underground damage efficiency.However,due to the complex geological structure of shallow underground and the superposition of propagation modes,it is difficult to obtain source information and the positioning accuracy is not very high.In order to achieve high-precision positioning,it is crucial to first extract the positioning-related feature information and parameters from the vibration signals collected by the sensor arrays deployed on the surface.In this regard,this thesis combines the advantages of deep natural source positioning principle and sensor array layout,focuses on the study of the characteristic parameters and source positioning method of underground explosion source information based on F-K analysis,and forms an underground shallow source positioning system,which provides a new method for solving the problem of high-precision positioning of underground space sources.Firstly,on the basis of consulting the research status of microseismic monitoring and positioning technology at home and abroad,according to the propagation characteristics of shallow explosion source signal,this paper designs and develops the system scheme of shallow source positioning.Secondly,in view of the shortcomings of the time difference positioning method,it is proposed to use the wavefront method of the taiwan array array to determine the position of the source;Using F-K analysis in the case of uncertain source azimuth information,the seismic signals recorded by sensors at different locations are processed by sensor arrays laid on the surface,and the F-K spectrum of the signal is calculated by the beam method,the energy distribution of the vibration wave field in different directions is distinguished,and all the slowness and azimuth angle are searched through the grid to find the best combination to determine the source position.Finally,the stability of the F-K spectrum of arrays of different shapes and number of sensors in the simulated wave field is studied by using waveform clustering method calculations,so as to evaluate the monitoring ability of the array and select the appropriate sensor array.According to the actual field conditions and experimental funds,the regular hexagonal array with the number of 7 sensors has a fairly good monitoring capability.Through simulation verification,the results show that the proposed F-K analysis-based underground seismic source signal feature parameter extraction method achieves effective signal feature picking,which has certain engineering application value in the field of microseismic testing.