A method of classifying radar emitters includes the steps of: (a) receiving pulses from multiple radar emitters over a plurality of consecutive first time intervals; (b) identifying pulses in each of the plurality of consecutive first time intervals corresponding to one or more first pulse trains using a first algorithm and de-interleaving the identified pulses from the plurality of first time intervals; (c) associating received pulses not identified and de-interleaved using the first algorithm with a plurality of consecutive second time intervals; and (d) identifying further pulses in each of the plurality of consecutive second time intervals corresponding to one or more second pulse trains using a second algorithm different from the first algorithm and de-interleaving the identified further pulses from the pulses associated with the plurality of consecutive second time intervals. Each consecutive second time interval is formed from two or more consecutive first time intervals.