Efficient Detection of Chirp Signals Based on the Fourth-Order Origin Moment of Fractional Spectrum

A novel detection algorithm for chirp signals based on the fourth-order origin moment of fractional spectrum (OMFrS) is presented. The fourth-order OMFrS of a chirp signal in discrete form is first deduced. By using the rough search result and the symmetric property of the fourth-order OMFrS of the chirp signal, the difference between the theoretical optimal transform angle and the detected result is calculated, and a more accurate estimation is obtained. Compared to the existing one-step search and two-step search methods, the proposed algorithm achieves better accuracy with high detection speed. Simulation results were given to prove the advantages of this new approach.