Adaptive digital filtering for coherent MTI radar

An adaptive digital filtering scheme of the open-loop type for coherent moving-target indicator (MTI) radars is described. The scheme consists of four basic components: 1.(1) a clutter estimator,2.(2) a digital filter,3.(3) a coefficient calculator for selecting the set of optimum filter coefficients, and4.(4) an automatic detector. The paper presents a procedure for selecting the appropriate set of filter coefficients by classifying the autocorrelation function of the received clutter so as to realize a prescribed false alarm probability, with the widest visible target space possible. Both finite impulse response (FIR) and infinite impulse response (IIR) forms of digital MTI filters are considered. The false alarm probability calculations are based on the Mohajeri bound; this theory is supported by computer simulations.