Research On The Location Of The Impact Point And The Underground Explosion Point Based On Seismic Waves

In modern warfare,how to effectively exert the existing military strike capability has become the focus of research in various countries.In the accurate strike evaluation,the positioning of the projectile drop point plays a decisive role in the identification of the strike effect.In the traditional technology,it is difficult to achieve precise positioning due to external factors,and when the warhead invades the ground,there is a big limitation in using the existing method to achieve positioning.Seismic waves are passive signals transmitted by the Earth as a medium.They are not affected by external factors such as terrain and weather conditions,making them highly resistant to interference and survivability.By receiving the seismic wave signal through the detector,processing the seismic signal and extracting the effective information,the exact position of the seismic source can be calculated,and the location of the impact point or the ground initiation point can be achieved.Based on this,this paper has carried out the following research on the positioning method of projectile drop point and underground detonation point.(1)The theoretical basis of seismic wave localization is discussed.According to the propagation law of seismic wave,the characteristics of seismic wave propagation at projectile drop point and underground detonation point are analyzed.Based on the study of seismic wave types,the initial time of the algorithm is determined by the arrival of P and S waves.(2)Several time-frequency analysis methods for denoising seismic waves are compared and analyzed,A method combining CEEMD algorithm with improved threshold function for signal denoising is proposed.The denoised signal is used to the energy ratio method to accurately extract the arrival wave time.In order to verify the validity of this method,the model test and the actual seismic signal test are carried out.The advantages of this method are obtained by comparing the first arrival time extracted after wavelet transform and the first arrival time extracted directly by energy ratio method.(3)The seismic wave localization algorithm is studied.Due to the particularity of the seismic wave signal detonated by the projectile landing and the underground detonation point,many conventional algorithms cannot be used.This paper improves the positioning algorithm without pre-speed measurement,and uses the P and S waves to locate the first arrival wave and locate it.The algorithm is numerically simulated to verify the effectiveness and reliability of the algorithm.(4)The overall scheme of the test system is given,and the selection of geophone and its working principle are emphatically explained.Then,according to the attenuation of seismic wave velocity and the coupling between geophone and surface,the simulated source test is carried out,which lays a foundation for the follow-up test.