Highly Squint SAR Imaging Algorithm Based on DFT Filter Banks
JIANG Huai① ZHAO Huichang① Han Min② Zhang Shuning①
①(School of Electronic and Optical, Nanjing University of Science and Technology, Nanjing 210094, China) ②(State Key Laboratory of Millimeter Waves, Southeast University, Nanjing 210094, China)
The traditional highly squint SAR imaging algorithm reduces the difficulty in range migration correction by using the time-domain linear walking, and improves the azimuth focusing effect by applying non-linear scaling algorithm. However, the variable standard factor introduced also causes some difficulty for processing. To tackle this problem, this article proposes a new algorithm of azimuth focusing on basis of DFT filter bank theory. Compared with the traditional non-linear scaling algorithm, the new algorithm can compensate Doppler frequency rate better by no introduction of phase operation. The stability is improved and the calculation needed is also less than the traditional algorithm. The simulation results presented proves the effectiveness of the proposed algorithm.
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