Recognition of high-resolution ground targets

Under the illumination of high resolution radar wave, a target can not be considered as a single dot target, it must be an extended target composed of many scatter dots. This paper mainly studies the model and the echo character of millimeter high resolution ground target. Because of the moving between target and system, Doppler frequency is important and useful information. An extend target is composed of many scatter dots. Each scatter dot, because of different position and angle, generates different Doppler frequency. Each kind of target has different geometry form. There are great distinction of the number and the position of scatter dots among targets. An extended target echo is a complicated Doppler modulation signal. The distinction of Doppler modulation echo of different target is very great. This property is very usable for target recognition. First, the echo spectral is computed by Fourier transform. Second, we choose the total spectral energy and four segment spectral energy as characters. Finally, target recognition adopted BP neural network to get high recognition ratio.