Efficiency of digital adaptive rejection filters for MTI systems

The characteristics of nonrecursive digital adaptive rejection filters for MTI systems are analyzed, and it is shown that Chebyshev filters of orders 1 through 4 are the optimal filters of this class. These filters have a nonfeedback design, and exhibit a number of advantages over adaptive filters with correlation feedback from the viewpoint of the transient mode. The filter weight coefficients are calculated by simple analytical relations based on the spectrum width and the noise Doppler frequency. The filter efficiency is assessed on the basis of the correlated-noise suppression coefficient.