Passive Space Object Observation using LOFAR Radio Telescope and Software-defined Radio Receiver

The paper shows the first results of experiments on the passive coherent location of space objects using a LOFAR radio telescope and a simple universal software-defined radio receiver (USRP). In our passive radar system, the USRP receiver serves as the reference receiver and the radio telescope as the surveillance receiver observing outer space. GNSS signals are employed to synchronize the receivers. A commercial digital radio transmitter is used as an illuminator of opportunity illuminating space objects. The key details of the operation of the proposed passive radar system allowing for the detection of space objects are discussed. The obtained results confirm the possibility of building passive radar systems with antenna fields similar to the LOFAR antenna fields for observing space objects in low orbits illuminated by commercial terrestrial transmitters.