TOPSAR模式是合成孔径雷达的一种宽幅成像观测模式，其产品被广泛应用于海洋风场反演、洋流反演等定量化遥感。根据TOPSAR模式成像的特点，对经典雷达方程表达式进行适应性修正，并在此基础上提出一套适用于TOPSAR模式的辐射校正处理方法，给出一套完整的处理流程图。最后，利用国产高分三号SAR卫星的TOPSAR试验模式实测数据对文中提出的校正方法进行有效性的验证工作。
TOPSAR is an earth-imaging technique which can provide wide swath coverage. Its products have been widely applied in quantitative remote sensing applications such as ocean wind inversion and ocean current inversion. Depending on TOPSAR characteristics, this paper made several adaptive corrections to the expression of classical radar equation. Based on this, several radiation calibration methods for TOPSAR were proposed, and a complete processing flowchart was given. In the end, the effectiveness of the methods was verified by using the measured data of GF-3 TOPSAR test-mode.
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