Spectral Estimation

In this chapter, we consider the problem of spectral estimation and line enhancement. To simplify matters, we will assume throughout the chapter that the input is a multi-sinusoidal signal; such a signal could be produced by a hypothetical system comprising of a parallel bank of resonators, and our objective is not only to estimate the frequencies of these resonators but also to isolate the outputs of the different resonators i.e., the different components of the multi-sinusoidal signal. In short, we would like to locally reconstruct the various components of the input signal. Let us assume for a moment that we know the frequencies of the various components i.e., the configuration of the hypothetical system is known. The problem of local regeneration of the components now simply becomes one of setting the initial states of the resonators of the hypothetical system to the right value.