Metop/IASI revisited operations concept: several ways to minimize mission down time w.r.t. SEUs

摘要

The IASI instrument is Hying onboard MetOp-A satellite since October 2006. IASI provides scientific data for numerical weather prediction and climatology. CNES is responsible for the instrument development (3 flight models) with THALES ALENIA SPACE as prime contractor, the Level-1 data processing chain and the Technical Expertise Center. EUMETSAT operates IASI as a part of MetOp payload. There is a high demand on the instrument availability due to the operational mission of MetOp. During the first years of operation the IASI Data Processing Subsystem (DPS) was affected by a significant number of anomalies caused by SEUs (Single Event Upset), mainly over the South Atlantic Anomaly region and the polar regions. The consequences were mission outages lasting from a few hours to a few days. This paper will present the results of analysis and corrective actions put in place by CNES, EUMETSAT and THALES ALENIA SPACE to mitigate the IASI down time, addressing the following points : 1. the root cause of the susceptibility of IASI elements to high energy particles; 2. the implementation of faster on-ground recovery procedures; 3. the development, validation and implementation of on-board solution consisting of modification of IASI onboard management software; 4. the evolution for MetOp-B and MetOp-C.