The TanDEM-X mission, formed by the TanDEM-X satellite in cooperation with its almost identical twin TerraSAR-X (TSX), has mainly been designed to acquire bistatic synthetic aperture radar (SAR) images of the Earth. Initiated in 2010, the primary mission objectives were to generate a global digital elevation model (DEM) to perform scientific measurements and to explore novel SAR techniques. Up to the present day, all these objectives have been completed with outstanding results. In addition, the satellites maintained a stable image quality from the start throughout their entire lifetime. The ground segment, which was tailored to the capabilities of the space segment, as well as an excellent design and manufacturing of the satellites were the key elements to achieve such a performance. In addition, the elaborate calibration concept and a careful treatment of the on-board resources enabled full operability up to the present day and allowed additional mission objectives such as the generation of a Change-DEM layer as an update to the global DEM. The stable bus and SAR payload performance as revealed by long-term system monitoring provide the basis for further extension of the TanDEM-X mission for several more years. In the following paper, these long-term system monitoring results are presented to provide an overview of the evolution of the radar system. The results and experience gained with more than a decade of TanDEM-X mission operation are a great value for both the scientific and commercial community and serve as a forerunner for the development of future SAR missions.

中文翻译：

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经过10年的运行，TanDEM-X的长期系统性能

TanDEM-X任务是由TanDEM-X卫星与其几乎相同的双TerraSAR-X（TSX）合作形成的，其主要目的是获取地球的双基地合成孔径雷达（SAR）图像。该任务于2010年启动，其主要目标是生成一个全球数字高程模型（DEM），以执行科学测量并探索新颖的SAR技术。到今天为止，所有这些目标均已完成，并取得了出色的成绩。此外，卫星从一开始就一直保持稳定的图像质量。专门针对太空部分的能力而设计的地面部分，以及出色的卫星设计和制造，是实现这种性能的关键要素。此外，精心设计的校准概念和对机载资源的精心处理，确保了直到今天为止的全部可操作性，并允许执行其他任务目标，例如生成Change-DEM层作为对全球DEM的更新。长期的系统监控显示，稳定的总线和SAR有效负载性能为TanDEM-X任务再扩展几年奠定了基础。在下面的文章中，将给出这些长期的系统监视结果，以概述雷达系统的发展。TanDEM-X任务运行十多年所获得的结果和经验对于科学和商业界均具有巨大价值，并且是未来SAR任务发展的先驱。