A geolocation method and system for locating the source of interference to a high throughput satellite. The method involves determining relative power level differences between interference signals received by the victim spot beam and co-colored nearby spot beams on the same satellite. Using beam pattern data, the relative power levels for a pair of beams determines contour lines of possible location the correspond to the relative power difference in the signals received by the two beams in the pair. A point of intersection of contour lines from multiple pairs of spot beams indicates the location of the source of interference.