First experimental trials of passive DVB-T based space object detection with a single LOFAR radio telescope

The paper presents the results of the first experimental trials of space object detection using one of the LOFAR radio telescopes and the digital television (DVB-T) transmitter as the illuminator of opportunity. It is worth emphasizing that a single LOFAR radio telescope served as both surveillance and reference signal receivers in the experiments. The main part of the LOFAR telescope array was used to observe a space object, whilst a small part of the telescope array was directed towards the illuminator of opportunity to record the reference signal. One of the most important problems to overcome was the effective suppression of the direct-path component in a surveillance signal from the DVB-T illuminator of opportunity not too distant from the LOFAR radio telescope. The results regarding the passive detection of the International Space Station, included in the paper, confirm the possibility of observing the space object flying in low Earth orbit using the LOFAR telescope or another receiving system with a similar antenna array.