The realization of the parameter estimation of chirp signals using the fractional Fourier transform (FRFT) is based on the assumption that the sampling duration of practical observed signals would be equal to the time duration of chirp signals contained in the former.However,in many actual circumstances,this assumption seems unreasonable.On the basis of analyzing the practical signal form,this paper derives the estimation error of the existing parameter estimation method and then proposes a novel and universal parameter estimation algorithm.Furthermore,the proposed algorithm is developed which allows the estimation of the practical observed Gaussian windowed chirp signal.Simulation results show that the new algorithm works well.