Based On Parametric Clutter Model Of Space-time Adaptive Matched Filtering Technology Research

The demand of modern military airborne radar increased continually, the mostcritical problem is the suppression of ground clutter. The ground clutter received by theairborne radar shows the space-time coupling characteristics that is more complex, dueto the movement of the radar platform and multi-channel characteristics of the radarantenna. By changing the two-dimensional response of the system, space-time adaptiveprocessing (STAP) can form a notch matched with the clutter on the two-dimensionalspace-time plane, in order to suppress the clutter effectively.However, several real world operating constraints preclude theoretically optimumSTAP performance. It needs to provide a huge number of the training data, which alsobringing a considerable space-time covariance matrix and huge computationalrequirements. Therefore, STAP technical improvements to make it better applied inpractice is an important subject of current research.On the basis of the STAP technology, based on the clutter model STAP method isadvanced in this paper. This improved method is equivalent to the dimensionalityreduction processing to the optimum STAP. The work in this paper include as follows:1.Analyze the Doppler characteristics of airborne-radar-clutter, and establish amathematical model of the space-time-clutter based on the geometric relationship of theairborne radar ground and the clutter scatterer. Analyze the power spectralcharacteristics of airborne radar ground clutter, and simulate the two-dimensional powerspectrum of the clutter. On the basis of understanding the airborne-radar-cluttercharacteristics, two common airborne-radar-clutter suppression approach: the DPCAand STAP are introduced, that optimum STAP technique is analyzed as an emphasis,and their strengths and weaknesses are summarized.2.As to the improvement of optimum STAP technology, this paper using theAR-clutter-model-based STAP technology. Modeling of ground clutter AR model isintroduced, and several typical methods of the model order determination and modelparameter estimation are analyzed.3.Introduce the structure and the basic principles of parameterized adaptive matching filter, including the time-domain filtering, spatial whitening filtering, and the calculationof detection threshold and detection probability. Under the same clutter environment,the computer results using this improving method and optimal STAP method werecompared. The results proved when airborne radar applying in practice that there is notenough training data, the performance of parameterized clutter-model-based STAP isbetter than optimum STAP, and could be used in the practical project of the cluttersuppression.