“…The cluster of satellites forms a large (∼100m), sparse, multielement, time varying phased array with narrow beamwidth and concomitant grating or random sidelobes that introduce significant ground clutter into the received signal. Previous work described approaches to distributed space-based radar employing satellites in a single orbital plane [3,6,7,8,11,17]. In our previous work [9,10,12,13,14,15], the satellites were assumed to be in multiple, nearly circular, low Earth orbits with a common orbital plane and thus form a sparse, periodic, two dimensional transmit-receive array with limited along track dimension operating at one of a carefully selected set of PRFs.…”