Wang Gui, Zhang Heng, Li Bo, Yu Weidong
Department of Space Microwave Remote Sensing System, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100094, China.
School of Electronic, Electrical and Communication Engineering, University of Chinese Academy of Sciences, Beijing 100049, China.
Sensors (Basel). 2025 Apr 27;25(9):2770. doi: 10.3390/s25092770.
Nonlinear frequency modulated (NLFM) signals can be used to enhance the resolution, anti-jamming capability, and imaging quality of synthetic aperture radar (SAR) systems through optimized design, demonstrating substantial application potential. However, in a SAR system using NLFM signals, the non-start-stop effect, caused by the continuous motion of the platform during pulse transmission and reception, introduces significant errors, resulting in target defocusing. To tackle this problem, this paper proposes a general numerical error compensation method dedicated to NLFM signals. First, the error model is correspondingly derived from the non-start-stop assumption. Then, a phase compensation method is designed through numerical calculations. Simulation experiments are performed to validate the effectiveness of the proposed method. This method provides a robust error compensation framework for high-resolution SAR systems using NLFM signals.
非线性调频(NLFM)信号可通过优化设计用于提高合成孔径雷达(SAR)系统的分辨率、抗干扰能力和成像质量,展现出巨大的应用潜力。然而,在使用NLFM信号的SAR系统中,由于平台在脉冲发射和接收期间的连续运动所导致的非起止效应会引入显著误差,从而导致目标散焦。为解决这一问题,本文提出一种专门针对NLFM信号的通用数值误差补偿方法。首先,从非起止假设相应地推导误差模型。然后,通过数值计算设计一种相位补偿方法。进行仿真实验以验证所提方法的有效性。该方法为使用NLFM信号的高分辨率SAR系统提供了一个稳健的误差补偿框架。