MISTIGRI instrumental concept for high-resolution thermal infrared imaging

Abstract

High resolution images in the Thermal infrared provide a way to detect irrigated fields, to measure evapo-transpiration and detect plant water stress. Models and algorithms have largely improved to yield very good results. However the only inorbit satellites providing high resolution images in the thermal infrared domain (Landsat, Aster) are long beyond their design lifetime. Furthermore, they do not provide frequent acquisitions (1 image every 16 days for Landsat and Aster, while 1 image per couple of days would be required to monitor plant water stress). There is indeed a need for high resolution and high repetitivity thermal infrared data for hydrological applications.CNES carried out a feasibility study of such a mission on a microsatellite. The mission is called MISTIGRI (MicroSatellite for Thermal InfraRed Ground Surface Imaging). The preliminary payload design was performed by Thales Alenia Space for CNES. An instrumental concept was proposed which fulfils the mission requirements. The study addressed both cooled and uncooled solutions, although a micro-bolometer detector was preferred after trade-off. This paper addresses the results of the MISTIGRI payload feasibility study; it presents the mission requirements, the proposed instrumental concept, describes the major subsystems and provides the preliminary performance budgets.

A compact thermal infrared imaging radiometer with high spatial resolution and wide swath for a small satellite using a large format uncooled infrared focal plane array

“…However, in the case of a simple "push broom" imaging using an uncooled IR-FPA, it is difficult to achieve a high spatial resolution of 30-50m, because the detector time constant (thermal response time) is about 10-16ms and the satellite ground speed is about 7km/s, the spatial resolution on the surface, therefore, is limited from 70m to 112m. In the design of MISTIGRI instrument, the supermode concept with on-ground TDI-like binning is adopted [12].…”

“…The GSD of SUCH is 230 m with spatial swath width of 59 km CNES is carrying out a feasibility study of high resolution IR image sensor using an uncooled microbolometer on a microsatellite. The mission is called MISTIGRI (MicroSatellite for Thermal InfraRed Ground Surface Imaging) [12][13][14]. The main mission of the MISTIGRI is to measure the surface temperature which can be directly related to the surface energy fluxes, evapo-transpiration and plant water stress.…”