TerraSAR-X/TanDEM-X Mission and CalVal Status with a focus on rainforest acquisitions for LTSM

Abstract

After more than a decade of successful radar operations in space, the German twin radar satellites TerraSAR-X (TSX) and TanDEM-X (TDX) continue to deliver SAR products at their well-known excellent image quality, despite the advanced age of both instruments. This high level of data quality relies on a continuous monitoring of the instrument health based on dedicated long-term system monitoring (LTSM) data acquisitions over both natural distributed and man-made point targets. In the first part of this presentation we give an overview of the TSX/TDX mission status, discuss instrument health, the current calibration status and give an outlook on the planning of the upcoming mission phases. In support of the ongoing discussion on requirements of natural distributed targets for usage in SAR system calibration we then focus on the long-term system monitoring time series of data acquired over the Amazon rainforest for monitoring both missions' RF frontend performance. We discuss sources of observable variation in these data sets and illustrate potential pitfalls when selecting data suitable for monitoring the calibration state of a SAR system.