Parameters extraction of linear FM signal using fractional autocorrelation

The parameters of linear frequency modulated (LFM) signal include instantaneous frequency, initial frequency and initial phase. In this paper, an algorithm for parameters extraction of linear FM signal based on fractional autocorrelation is proposed. The algorithm is to calculate the fractional autocorrelation at rotation angle α and the corresponding integral at the order of p, while a peak value appeared at a certain angle α in fractional Fourier transform (FrFT) domain, then the signal can be detected and the parameters can be extracted. Finally, computer simulations are provided to illustrate the validity of the proposed algorithm.