THE ON GROUND CALIBRATION, CHARACTERIZATION AND VERIFICATION APPROACH FOR THE CIMR INSTRUMENT

L. Lazzara¹

¹Thales Alenia Space Italia

CIMR (Copernicus Imaging Microwave Radiometer) mission, part of the European Commission’s (COM) Copernicus Expansion Programme (CopEx), will carry a wide-swath conically-scanning multi-frequency microwave radiometer and has as primary objectives to provide observations of sea-surface temperature, sea-ice concentration and to ensure European operational continuity of L-band as well as enhanced AMSR type measurement capability [1]. Very challenging requirements for the missions are reflected in a very complex architecture for the instrument that relies on sensing 50 RF chains to retrieve the full Stokes Vector components. Furthermore, in order to cope with the present (and future) interferer scenario, RFI detection and mitigation capabilities have been included in the radiometer backend.

Nowadays the development of the CIMR instrument is in an advanced stage and the EM ground test phase is coming. Ground test campaign for space borne radiometers are typically challenging tasks. Stringent requirements to be verified put hard constraints on the test design, including facility and tools. Often special custom support equipment is needed to be developed in the frame of the project in order to correctly perform the calibration, characterization and verification tasks.In the specific case of CIMR, the problems are intensified by the high number of radiometric channels to be tested, the very wide frequency range of operations and the challenging radiometric requirements. The definition of the CIMR instrument test campaign is a process that is in progress since the beginning of the program, when the need of special test tools have been highlighted and is going to be consolidated. Test facilities have been identified and the test flow flows designed.This work describes the design and development approach for the definition of the CIMR ground spectral and radiometric test campaign, including brief description of the test philosophy, the test flow and an overview of the main custom test support equipment developed in the frame of the CIMR project.