Preliminary concept of a space-based radar for detecting mm-size space debris

Presently, there exists very little knowledge about the density and distribution of space debris of the size of a few millimeters. The reason is that ground-based systems are not sensitive enough to detect such small objects. Space-based radars have the potential through in situ measurements to validate or discard the current space debris models and to help filling this knowledge gap. This paper presents a preliminary design of a space-based radar for detecting mm-size space debris and discusses the potentials and limitations of such a concept.