SMOS payload status after six years in orbit operational and thermal performance, calibration strategy & RFI management

Abstract

The SMOS Payload is a single instrument, the Microwave Imaging Radiometer using Aperture Synthesis (MIRAS), which is a passive microwave 2D-interferometric radiometer working in the L-Band. The MIRAS antenna aperture is synthesized from 69 antenna elements arranged in a Y-shaped configuration. In this paper, the current status of the SMOS payload after more than 6 years in orbit is overviewed from four different perspectives: (1) Operational Performance, indicating how some anomalies have been dealt with in orbit and the availability figures accounting for more than 99%, (2) Thermal Performance, where we review the thermal requirements of the instrument and we analyze the temperature evolution of the system in some examples, (3) Calibration Strategy, being quite demanding for MIRAS, have required only few changes since launch, and (4) RFI Management, where we provide an overview of the RFI situation since launch and the progress achieved after 6 years of due actions by ESA to switchoff or mitigate the impact of interference sources.