Comparison of Maximum Likelihood and Generalized Monopulse DOA estimation techniques on SOSTAR-X GMTI-STAP data

The maximum likelihood (ML) angle estimator is widely considered the ldquooptimumrdquo angle estimator, particularly in presence of adaptive digital beam forming (ADBF). A number of papers in literature suggest several solutions to implement the bi-dimensional Doppler - azimuth angle ML estimation in a cost-efficient manner. Nickel demonstrated that the generalized monopulse technique can be derived from the ML technique just as a first order Taylor approximation of the ML estimator, at a minor implementation cost. This paper compares the results obtained by implementing the ML and the generalized monopulse techniques on the GMTI-STAP data gathered during the SOSTAR-X flight trials.