In allusion to energy of echo from rotor blade is too low to be detected

the paper analyses the time characteristic and frequency characteristic of echo from rotor blade

ground clutter and target clutter based math model of echo from rotor blade and the thought of detection for echo from rotor blade in time domain after the clutter is filtered out in frequency domain is brought forward.In allusion to the actuality of recognition for helicopter

the thought of the confident level of helicopter target recognition is guaranteed by controlling the false alarm rate of detection for echo from rotor blade is put forward and statistical distributing of clutter residual and noise after clutter is filtered out in frequency domain is researched and the detection based sliding window is applied to partition the observation vector into the detection cell and reference cell for clutter to accomplish the CFAR detection for echo from rotor blade.The simulation result indicate that the method of filtering clutter can filter the ground clutter and target clutter effectually to improve the detection SCNR of echo from rotor blade.The detector in time domain for echo from rotor blade can work well when the SNCR is low.