Range recursive and Taylor series based space-time adaptive processing for range dependent clutter rejection

This paper presents a new space time adaptive processing (STAP) for the rejection of range dependent ground clutter in order to detect slow moving targets with an airborne radar. STAP usually requires the estimation of the clutter plus noise covariance matrix from secondary data neighboring the cell under test. However, in most radar antenna array architectures and/or configurations which are different from the conventional uniform linear antenna array and side-looking configuration the clutter is range dependent. We recently proposed the use of a Taylor series expansion of the clutter plus noise subspace in conjunction with the eigencanceler-based (EC) STAP in order to mitigate the range non-stationarity of the clutter. In this paper, the computationally costly EC is replaced by a range-recursive algorithm which is capable of tracking non stationarities with a reduced complexity compared to the EC. The performance of the proposed algorithm is satisfactorily tested and compared to other algorithms in the case of a bistatic configuration.