MMSE estimation of nonlinear parameters of multiple linear/quadratic chirps

An iterative algorithm similar to our MMSE estimation procedure proposed in another paper by the authors is applied to parameter estimation of multiple superimposed chirp signals in white Gaussian noise. The necessary parameter initializations of the procedure are accomplished by peak detections in the Choi-Williams (1981) time-frequency distribution of the data followed by application of the least-squares principle. A comparison between our scheme and the alternating projection (AP) method is demonstrated by computer simulation.