Modified Adaptive Chirplet Decomposition and Its efficient Implementation

A new algorithm of signal decomposition-modified adaptive chirplet decomposition (MACD) is presented to overcome the deficiency of basis functions with linear time-frequency relations. The chirplet atom is extended to quadratic frequency modulated signal, and it can approach the nonlinear time varying components of the original signal. At the same time, a efficient algorithm is presented by computing the cubic phase (CP) function of the signal, it is shown that the CP function is concentrated along the instantaneous frequency rate law, and the peak of the CP function yields the estimates of the coefficients of quadratic and cubic phase, the time center and the amplitude. Then the initial frequency and the time extent can be obtained by the dechirp technique. The scheme of the algorithm is shown in this paper, and the results of echolocation signal from brown bat demonstrate the validity of the method proposed