Abstract Forest height is an important variable for modeling terrestrial carbon storage and global carbon cycle dynamics. Spaceborne SAR Interferometry (InSAR) has the sensitivity to measure canopy height and the underlying topography. In this paper, we refine and automate an interferometric ground finding approach that exploits few-look (2- to 4-look) averaged interferograms and incorporates the use of a coherent electromagnetic simulator and field inventory data. Using the coherent electromagnetic simulator, an InSAR simulation based on field data is performed to study the true ground position as a function of the statistics of few-look InSAR phase heights from a model perspective. With this statistical model, both the underlying topography and the canopy height (mean and top canopy height) can be estimated. Using German Aerospace Center's (DLR) single-baseline single-polarization TanDEM-X InSAR data, we validate the approach over a Brazilian tropical forest (Tapajos National Forest) with both field inventory and lidar data. As validated against lidar data, the underlying topography is estimated to an accuracy of 3 m. At one hectare aggregated pixel size, InSAR phase-center height is best compared with the field/lidar mean canopy height with an accuracy of 2–3 m, while InSAR-inverted total height best characterizes the lidar top canopy height with an accuracy of 4–5 m. Given the global data availability of TanDEM-X and the future TanDEM-L, this approach has the potential for wall-to-wall mapping of forest height as well as underlying topography and also serves as a complementary tool to other existing InSAR, Polarimetric InSAR (PolInSAR) and SAR tomography (TomoSAR) methods when only single polarization and/or baseline data are available.

中文翻译：

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使用单基线单极化 TanDEM-X SAR 干涉测量法自动估计巴西热带森林上的森林高度和底层地形

摘要 森林高度是模拟陆地碳储存和全球碳循环动力学的重要变量。星载 SAR 干涉测量 (InSAR) 具有测量冠层高度和底层地形的敏感性。在本文中，我们改进并自动化了一种干涉式地面查找方法，该方法利用了少视（2 到 4 视）平均干涉图，并结合了相干电磁模拟器和现场库存数据的使用。使用相干电磁模拟器，执行基于现场数据的 InSAR 模拟，以从模型角度研究作为少视 InSAR 相位高度统计的函数的真实地面位置。使用这个统计模型，可以估计底层地形和冠层高度（平均和顶部冠层高度）。使用德国航空航天中心' s (DLR) 单基线单极化 TanDEM-X InSAR 数据，我们使用现场库存和激光雷达数据验证了巴西热带森林（塔帕霍斯国家森林）上的方法。根据激光雷达数据进行验证，基础地形估计精度为 3 m。在一公顷的聚合像素大小下，InSAR 相位中心高度与现场/激光雷达平均冠层高度相比最好，精度为 2-3 m，而 InSAR 倒置总高度最好以 4 的精度表征激光雷达顶部冠层高度–5 米。鉴于 TanDEM-X 和未来 TanDEM-L 的全球数据可用性，这种方法具有森林高度和底层地形的墙到墙映射的潜力，并且还可以作为其他现有 InSAR 的补充工具，