Asymptotical Separation of Polynomial Signals from Harmonics by Singular Spectrum Analysis
摘要
General approach to asymptotic signal extraction from an additively perturbed series with the help of Singular Spectrum Analysis (SSA) has already been described in [5]. This paper considers an example of this analysis applied to a polynomial signal and additive noise as linear combination of harmonics. In this case, the so-called reconstruction errors ri(N) of SSA have been found to uniformly tend to zero as the series length N tends to infinity. More precisely, we have proved that maxi |ri(N)| = O(N–1) as N → ∞ and for a “window length” L ~ αN, α ∈ (0, 1). This solves the problem of the accuracy of asymptotic separation of a polynomial signal from the seasonal component. The results on discrete Chebyshev polynomials in equally spaced points are essentially used to go to a polynomial of an arbitrary order from a linear signal, which was addressed for the case L = (N + 1)/2 in [7].