We describe a method for identifying the source of a satellite interferer using a single satellite.The technique relies on the fact that the strength of a carrier signal measured at the downlink station varies with time due to a number of factors, and we use a quantum-inspired algorithm to compute a ''signature'' for a signal, which captures part of the pattern of variation that is a characteristic of the uplink antenna. We define a distance measure to numerically quantify the degree of similarity between two signatures, and by computing the distances between the signature for an interfering carrier and the signatures of the known carriers being relayed by the same satellite at the same time, we can identify the antenna that the interferer originated from, if a known carrier is being relayed from it. As a proof of concept, we evaluate the performance of the technique using a simple statistical model applied to measured carrier data. KEYWORDSidentification, interferer, quantum inspired, single satellite, singular value decomposition INTRODUCTIONThe increasing demand for satellite communication links has led to an increasing number of satellite signals and to an increasing amount of uplink interference. The causes of this interference include the growth in the number of small ground terminals, low-quality equipment, poor installations and maintenance, uplink personnel mistakes (human error), faulty equipment, incorrectly pointed antennas, adjacent satellite interference, terrestrial service interference, and sometimes intentional jamming. 1,2 Satellite operators are therefore increasingly interested in solutions not only for detecting interference, which is the main task of a satellite monitoring system, but also to identify its source.The traditional approach is to geographically localize, or geolocate, the transmitting station of an interferer. However, most localization systems need to receive the interference signal via two adjacent satellites in order to perform geolocation, 3-7 and there are a number of limitations associated with this approach:• An adjacent satellite must be available that is equipped with transponder(s) receiving components of the interfering signal and a reference signal (same uplink frequency range and same polarization).• The interference and reference signals need to have enough crosstalk energy between the primary and adjacent satellites to achieve a sufficient level of correlation.• Accurate ephemeris data must be available for both satellites.• The reference signal needs to be received from both satellites via transponders operating with the same physical local oscillators (LOs) as the transponders retransmitting the interference signal.• If the system is installed at only one earth station, the downlink signals of both satellites need to be receivable at this earth station (downlink beams of both satellites need to cover the measurement site location). If this is not possible (beams pointing to different locations), the system needs to be installed at different locations inside the ...