Abstract: The clutter distribution of an airborne radar with non-sidelooking array varies with ranges, and samples in different range gates are not independent identically distributed vectors, so that the statistical space-time adaptive processing (STAP) methods degrade.In this article, a new clutter suppression algorithm for an airborne radar with non-sidelooking,i.e., the multiple space angle compensation (MSAC) method, is proposed. This method involves first a preprocessing with angle-Doppler compensation (ADC) to eliminate the non-homogeneity at the centers of the clutter spectrum in different range gates and then the MSAC to accomplish the alignment of the space angles of different range gates at multiple Doppler frequencies.Simulation results show that with only a little increase of the computation load the proposed method can further reduce geometry-induced non-homogeneity of a non-sidelooking array and outperform significantly the ADC algorithm.

Key words: non-sidelooking array, multiple space angle compensation, clutter suppression, angle-Doppler compensation, space time adaptive processing