Brown模型在对地高度表回波的适用性分析

Applicability Analysis of Brown Model to Ground Altimeter Echo

Brown模型适用于窄波束雷达高度表对海洋回波的表征,但在表征宽波束雷达高度表对地物目标场景下的回波时,Brown模型需要修正其在大入射角下的后向散射系数。为检验Brown模型在平坦陆地下的适用性,试验基于机载高度表实测回波数据,验证了修正后的Brown模型可以表征地形起伏较小的平坦地物目标的回波功率变化趋势,但是无法体现回波中出现的不规则尖峰。在地形起伏较大区域,Brown模型则不再适用。

The Brown model is suitable for the characterization of the ocean echo from the narrow beam radar altimeter,but when characterizing the echo from the wide beam radar altimeter to the ground target scene,the Brown model needs to modify its backscatter coefficient at a large incident angle.In order to test the applicability of the Brown model under flat land,the experiment is based on the measured echo data of the airborne altimeter.It is verified that the modified Brown model can characterize the change trend of the echo power of flat objects with small terrain undulations,but it cannot reflect the irregular spikes in the echo.In areas with large undulations,the Brown model is no longer applicable.