6. Track Irregularity Time Series Data Wavelet Decomposition-Reconstruction The wavelet transform [28–31] is a new rapidly evolving supplier AEB071 field of applied mathematics
and engineering disciplines; it is a new branch of mathematics, which is the perfect crystal of functional analysis, Fourier analysis, sample transfer analysis, and numerical analysis. Data process or data series is converted into stages data series to find similar spectrum characteristics based on some special functions in the wavelet transform, so as to achieve a data processing. Wavelet transform is local transformation of space (time) and frequency, and it can effectively extract information from the signal and do multiscale detailed analysis to function or signal through stretching and panning arithmetic. “Wavelet” means the waveform with a small area, the limited length and 0 mean, in which “small” refers to the wavelet with decay, “wave” refers to its volatility, and its amplitude shocks in alternating positive forms and negative forms. Compared with the Fourier transform, wavelet transform is the localized analysis of the time (space) frequency. It does multistage subdivision gradually through stretching shift operation on the signal (function) and ultimately achieves time segments at high frequency and frequency segments at low frequency and can automatically adapt to the requirements
of time-frequency signal analysis, and then can focus on any detail of the signal and thus can solve the difficult problem of Fourier transform. It has become a major
breakthrough in the scientific method since Fourier transform, so wavelet transform is even called “mathematical microscope”. The decomposition of the function into the representation of a series of simple basis functions has an important significance both in theory and in practice. In this paper, Daubechies wavelet [32, 33] is used to do decomposition in track irregularity time series data, which is the general term for a series of binary proposed by the French scholar Daubechies, and multiscale wavelet decomposition of the signal can be done by it. Assume a known signal fx=∑aj,kϕj,kx, fx∈Vj. (6) The coefficients aj,k, k ∈ Z are known in the formula. Now f(x) is decomposed into two components of space Vj−1 and space Wj−1: fx=∑aj−1,kϕj−1,k(x)+∑dj−1,kψ(x). (7) In a given situation of sequence aj,k, respectively, Carfilzomib the (J − 1)th approximate level sequence aj−1,k and (j − 1)th details level sequence dj−1,k can be calculated. According to two scale relations, it can be known that ϕj−1,k=2j−1/2ϕ2j−1x−k=2j−1/22∑shsϕ22j−1x−k−s=∑shs2j/2ϕ2jx−2k+s=∑shsϕj,2k+sx. (8) Similarly, it can be calculated that ψj−1,kx=∑sgsϕj,2k+sx. (9) It can be inferred according to the above relation that aj−1,k=fx,ϕj−1,k(x)=fx,∑shsϕj,2k+s(x)=∑sh−sfx,ϕj,2k+sx=∑sh−saj,2k+s=∑aj,nh−n−2k=aj×h′2k. (10) In the formula, hk′=h–k.