Application Of Fractional Fourier Transform In The Seismic Data Processing

With the rapid development of modern seismic exploration technology andthe demand for resources increases day by day, which makes all kinds ofmethods in seismic data processing to a higher efficiency, higher accuracy andresolution direction. In the seismic data, the analysis of the signal andeffectively processing requirements are also getting higher and higher, in thepast for signal analysis are based on stationary signal analysis method is adopted,and processed by the fourier analysis method, with the continuous developmentof exploration technology, application of fractional Fourier transform from theevolution of Fourier transform to gradually to the exploration technique, andeffective for non-stationary signal is studied, and by many engineering andtechnical aspects of attention and was able to by many researchers, because ithas the nature of many traditional Fourier transform has not. In recent years, thefractional Fourier transform has been used in many scientific research andengineering technology, such as time-frequency analysis, sweep frequencyfiltering, time-varying filtering, wavelet transform, artificial neural network andmultiple transmission etc.. In addition, the fractional Fourier transform in imageprocessing, diffraction theory, quantum mechanics, optical transmission, opticalsignal processing, optical system and optical image processing and other areashas been widely used.From these applications we summarize fractional Fourier transform is akind of unified time-frequency transform, but also reflects in the time domainand frequency domain information of a signal, and the two type commonly usedtime-frequency distribution is different fractional fourier transform by singlevariable to represent the time-frequency information, and there is no the crossterm interference. Compared to the traditional Fourier transform, the fractional Fourier transform is very suitable for processing non-stationary signals,especially chirp signal most, and a free transform order number P. So thefractional Fourier transform under the same conditions to get traditionaltime-frequency distribution or the Fourier transform to get different results, andthe obtained effect than other method has higher resolution and improve thesignal to noise ratio, effectively eliminates some noise caused by. As thefractional Fourier transform with fast discrete algorithm is relatively mature, sothe better effect also do not need to pay more computational expense.The purpose of this paper is mainly to discuss the main advantage offractional Fourier transform in time-frequency analysis, shows that it is moresuitable for the application in seismic data processing. This article first throughtwo groups of signals to indicate the optimal P fractional Fourier transformvalue, the optimal p value after fractional Fourier transform to get the besttreatment effect is helpful for the research and treatment of the next, and thenthrough the frequency analysis and fractional Fourier transform of the other, andwith some graphics using chirp signal fractional Fourier transform energyaggregation to illustrate them with fractional Fourier transform are different,thus further illustrate the superiority of the fractional Fourier transform, andthen through the effective fractional Fourier transform in denoising and by theprocessing of real seismic data processing, the signal-to-noise ratio of seismicdata with improved, more clear description of the fractional Fourier transform ismore suitable to applied in seismic data processing.