Modified Multisine Fitting Algorithm for the Estimation of Time-Varying Carrier Frequency Signal Parameters

Abstract

In this paper, a procedure for the estimation of the harmonic signal components of a signal with continuous time-varying carrier frequency it is proposed. The procedure in a first phase estimates the coarse trend of the time-varying carrier frequency and then the coarse values of the harmonic components. In particular, the harmonic components are estimated by using the modified three parameters MultiSine Fitting Algorithm (MSFA), here proposed. To take into consideration the frequency offset that can be introduced in the frequency estimation phase, an iterative procedure is also proposed to minimize the difference between the estimated parameters and those of the original signal. The iterative procedure is based on a modified four parameters MSFA. Both the three and four parameters MSFA are modified to operate with the time varying frequency. The main advantages of the proposed procedure are: (i) a reduced sampling frequency is required, and (ii) the spectral leakage is avoided.