Any two N × N costas signals must have at least one common ambiguity sidelobe if N > 3—A proof

A. Freedman, N. Levanon
1985 Proceedings of the IEEE  
The initial estimate of s, and s2 is obtained by the Tufts-Kumaresan (TK) method 121, 161, 171, [Ill, that is by forward or backward linear prediction (depending on whether one is looking for falling or rising exponential components) after low-rank approximation to the observed data matrix or an estimated correlation matrix. A standard quasi-Newton method is then used for the maximization of E, 181. The performance of this method is studied by computing the bias and the standard deviation of q
more » ... ard deviation of q ' s and sk's obtained from 500 trials. A different realization of noise is used for each trial. Comparisons between the Newton estimates, the TK estimates, and the CR bound for unbiased estimates are presented in Fig.
doi:10.1109/proc.1985.13329 fatcat:xm3cxkj62rbutpfpiqynmdwn2i