The properties of range profile of aircraft

Wideband radar can obtain more target information, for its range resolution is high. With an airplane, because its size is smaller than the resolution of conventional radar, it can be regarded as a ´point´. But to wideband radar, with a few hundred MHz bandwidth, the range resolution is smaller than a meter, and the airplane echoes of one impulse compose a high resolution range profile (HRRP), which includes target shape information, so it can be used for automatic target recognition (ATR). It is difficult to recognize a target by observing range profiles by eye; although the range profile is divided into range resolution cells, every range cell still has many scatterers, so that the complex amplitude of one range cell echo can be regarded as the sum of the echoes of many scatterers. When the angle-of-sight has changed little, although the change of the range of each scatterer to the radar is small, it is great relative to the wavelength and leads to the phase difference being great, which results in the complex amplitude varying with aspect, that is, the aspect sensitivity is great. In order to use the range profile for target recognition, the properties of the range profile need to be studied. Preprocessing is needed to obtain stable range profiles