Bistatic Detection of LEO Satellites from Very Long Distances Using LOFAR Radio Telescope

The paper presents the results of experimental investigations on the capabilities of detecting very-long-distance space objects moving in Low-Earth Orbit (LEO) based on bistatic measurements using the antenna array of a LOFAR (LOw-Frequency ARray) radio telescope and a non-cooperative radar illuminator operating in the VHF band. In this system, the signal transmitted by the non-cooperating radar is recorded using a relatively simple reference signal receiver located near the illuminator. The sensitive antenna array of the LOFAR radio telescope enables the reception of weak echo signals reflected from space objects orbiting in LEO, even those located extremely far from the illuminator and receiver in the bistatic sense. The detection of very distant and high-speed objects is made possible through the utilization of a dedicated object motion compensation method.