Abstract:

Rotor synthetic aperture radar (ROSAR) is a new kind of imaging mode, due to the complex expression of target’s range derived by its circular trajectory of motion, expanding target’s range to the second order brings severe defocussing in azimuth under the condition of wide-beam. To deal with this problem, a new imaging algorithm of ROSAR based on Cardano’s formula is proposed. Considering expanding the expression of target’s range to a fourth order polynomial and deriving the two-dimensional spectrum of echo, an effect of range cell migration (RCM) on image is made. The image is obtained by compensating RCM based on Cardano’s formula and the calculated amount of method is showed. Simulation results validate the feasibility and the robust in noisy environment of the proposed algorithm.