In this paper shows the analysis of the implementation of a adapted filter to a chirp signal in the domain of the optimal order of the FrFT. Here express the equations for a chirp signal receptor in the frequency domain and a general equation in the Fourier fractional domain using the Phase stationary principle (PSP), with the objective of expose the adapted filter limitations, describe the affecting parameters the chirp signal and demonstrate the better performance through use of adapted filter in the Fourier fractional domain of optimal order for special cases.