A fast parameter estimation method for multicomponent LFM signal based on FRFT

Aiming at the problem of low search efficiency of traditional methods, this paper proposes a method to quickly and accurately estimate the parameters of multi-component linear frequency modulation (LFM) signal. Using the rotation equivalent relationship between the fractional Fourier transform (FRFT) and the Wigner distribution (WD), the calculation method of the optimal rotation angle of the LFM signal in the FRFT is deduced. Considering the problem that mutual interference between multi-component signals affects the estimation accuracy, an efficient search method is proposed to improve the estimation accuracy under the condition of less calculation amount. The simulation results show that this method can achieve fast and accurate estimation of multi-component LFM signal parameters.