Optimal Configuration Design and Clutter Suppression Performance Analysis for Spaceborne Bistatic Surveillance Radar Systems

In spaceborne bistatic radar systems, the large spatial separation between the transmitter and receiver, combined with the high-velocity motion of satellite platforms, causes the clutter to exhibit pronounced range-dependent behavior in both theDoppler and spatial domains. This rangedependence severely limits the number of independent and identically distributed (i.i.d.) training samples available for space–time adaptive processing, thereby degrading clutter suppression performance. To address this issue, a generalized space–time clutter model applicable to arbitrary bistatic satellite geometries and array configurations is first established based on an unperturbed orbital motion model. Building on this foundation, the clutter suppression characteristics of high-transmitter/low-receiver (Hi–Lo) configurations are examined. Considering key factors such as observation-region latitude, maximum common dwell time, andDoppler Spread Divergence (DSD), four representative spaceborne bistatic configurations are designed to evaluate clutter suppression performance, through which the most and least favorable orbital geometries are identified. Furthermore, to mitigatenon-stationary clutter and enhanceairborne moving target indication (AMTI) capability, a dimensionality-reduced clutter suppression method based on a three-dimensional sum–difference beam (3D-SDB) structure is proposed. Simulation results demonstrate that the joint optimization of bistatic configuration and the proposed algorithm effectively alleviatesnon-stationary clutter and substantially improves the minimum detectable velocity (MDV) forairborne moving targets.