Research On Processing Methods Of Linear Source Data

In recent years,the increasing number of high-speed rail lines makes the source of high-speed train attract the attention of geophysicists.Its many advantages make people consider the application of this signal for underground structure exploration.The linear source of the high-speed train is very different from other common source,so the corresponding processing method should also be determined through the relevant analysis of the theoretical source mechanism and the real data.The theoretical wavelet of high-speed train is simulated in this paper and its formation process is studied.Meanwhile,the main factors influencing the wavelet shape and spectrum are determined.Then the accuracy of the source mechanism is demonstrated using the model data and real data.The characteristics of the high-speed train signals are introduced,and a certain high-speed train signal is analyzed in time domain and frequency domain.Finally,three methods to calculate the speed of the trains are introduced as well as their used conditions and accuracy.In the processing of real data,a theoretical model is established and automobile source data is processed in this paper which determines that the primary processing direction of high-speed train data is harmonic suppression.Three methods are used for removing harmonics according to its characteristics,which are synchronous extrusion short-time Fourier transform,singular spectrum analysis and harmonic frequency calculation method.Then,the seismic interference method is used to process the data after harmonic suppression.Finally,the surface wave in the virtual source record is analyzed by multichannel analysis of surface wave,which proves the feasibility of high-speed railway source for shallow layers exploration.