Space object detection and characterisation with a passive space-borne bistatic radar

This paper presents a feasibility study and performance assessment of a simple and low-cost system to detect, characterise and potentially track space debris in Low Earth Orbit. The concept exploits any Earth-orbiting satellite broadcasting radio waves as illuminators of a bi-static radar system in which the receiver is equipped of a small antenna on board of a very low altitude orbiting CubeSAT. In fact, in principle the receiver can be installed on any low-altitude satellite (or even the International Space Station) and does not require a dedicated mission. Alternatively, it can be demonstrated that one can install the receiver on one or more CubeSATs flying at very low altitude (below 400km) and provide a dedicated service that does not increase the debris population. The paper will investigate the use of different illuminators at different frequencies. It will be shown that, depending on the integration time that ultimately depends on the time illuminator receiver and target are in view, one can detect objects down to few centimetres in size and recognize targets observed previously.