Research And Application Of Adaptive Filtering In Transient Electromagnetic Denoising

Based on the basic principle of transient electromagnetic prospecting,the one-dimensional forward response formula for transient electromagnetic is derived.Combining the characteristics of the main noise of transient electromagnetic,I discuss that the transient electromagnetic data signal is a kind of wide-band signal,which is easily affected by many kinds of noise.If the noise is not suppressed,the accuracy of the transient electromagnetic exploration method will be greatly affected.Based on the analysis of the advantages and disadvantages of the current electromagnetic noise reduction methods,the application of the minimum mean square(LMS)adaptive filtering method and the recursive least square(RLS)adaptive filtering method in the transient electromagnetic data filtering processing are proposed.The feasibility of the method is studied by the processing effect of the minimum mean square(LMS)adaptive filtering and the recursive least square(RLS)adaptive filtering method in the simulation of sinusoidal signal with Gauss white noise data.By comparing and analysing the key parameters of the least mean square(LMS)adaptive filtering method and the recursive least square(RLS)adaptive filtering method,the processing effect of two methods in one dimensional transient electromagnetic forward additive noise is studied.The applicability and effectiveness of the two methods are judged by the square method of quantitative analysis.It is determined that the adaptive filtering method based on recursive least squares(RLS)is more suitable for the de-noising of transient electromagnetic.Then using the two field response data of the transient electromagnetic field verified in the engineering example,the two field single point attenuation curves detected by a measuring point with a more prominent jump phenomenon in the section are filtered and analyzed,and the validity of the method is determined by a typical test point.Then,a recursive least squares(RLS)adaptive filtering method is applied to filter a section.The basic principle and the inversion procedure of the "smoke circle" inversion method is discussed,which has simple,fast and commonly used characteristics.And The smoke filter is applied to deal with the data before and after filtering,and get the result.The results are compared with those verified correctly.It is concluded that recursive least squares(RLS)adaptive filtering method can be used as an effective filtering processing method in transient electromagnetic data processing.On the basis of the research on the method of transient electromagnetic data denoising,the results of applying the recursive least square(RLS)adaptive filtering method to the transient electromagnetic data processing are analyzed.Finally,the adaptive filtering method is proved to be feasible in the transient electromagnetic data processing,and it can be carried out on the transient electromagnetic data.Fast denoising and broadening the effective processing methods and techniques of transient electromagnetic signal denoising..