Signature recognition for nuclear detonations.

Abstract

Experiments have been performed on the recognition of nuclear detections by using coherent optical data-processing systems. The data, E-field signals recorded with a 10 khz bandwidth, were available from only ten events, all airdrops. Since the signals were of an unknown form, they were classified into sub-groups by using a cross-correlation technique. Spatial carrier-frequency filters, constructed for these signals, were then tested to determine their ability to recognize all ten signals while rejecting noise from atmospheric sources. The experiments, although of a preliminary nature, show that all the test signals can be recognized with a two-channel filter and that the nearest noise peak (from six samples) is 6–8 db less than the minimum correlation peak from any of the ten signals.