“…Currently, scholars have conducted indepth research on the modeling and feature extraction methods of helicopter. There are three main modeling methods: (1) RCS model [4][5], which obtains echoes by calculating the target backward scattering field and can fully consider the scattering characteristics of the target, and the model is the most accurate, but the calculation is too complicated; (2) Scattering point model [6][7], which is the most traditional and applied modeling method, analyzes the target by equating it into a number of scattering points. This method can be applied into complex scenes with non-uniform distribution and different scattering intensity, but the amount of computation increases with the increase of the number of scattering points; (3) Integral model [8][9][10][11], which equates the target as a rigid, uniform line, with simple mathematical calculation, can reflect the structural differences of the target as a whole.…”