Helicopter Blade Parameter Extraction For Purposes Of Radar Target Indentification
The positive classification and identification of airborne targets beyond the visual range by using the reflected radar signal has become an increasingly valuable capability for the defence force of a country. The rotating structures on an airborne target cause additional Doppler modulation in the return signal, known as the micro-Doppler effect. Information on the rotating structures can be extracted from this effect. A technique based on time- frequency and tomographic analysis is introduced in this research to extract certain helicopter blade parameters which will aid in the identification of a helicopter. The proposed algorithm shows that (under certain conditions) it is possible to extract the number of main rotor blades, the blade length and the rotation rate of the helicopter's main rotor. These features can be used to determine the make and model of a particular helicopter.