Abstract: The characteristics of helicopter echoes are analyzed. According to the cyclostationary characteristics ofhelicopter rotor blade echoes,the correlation processing for long time blade echoes is used to increase the signal-noiserate of flash echoes for improving the detection range for hovering helicopters. At the same time, the cross-correlation coefficient based detector can provide the classification results for hovering helicopters by the period of flash echoes. The processing results of simulation and real data are presented.

Key words: target detection, target classification, cyclostationary, correlation processing, helicopter