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Almost all types of satellite sensors are actively or passively cooled, in many cases down to cryogenic temperatures. The goal is to suppress thermal noise in order to achieve the highest possible signal-to-noise ratio. Thus, cryocoolers are critical components in satellite systems, and in many cases key enablers. For instance in Earth Observation (EO) systems, mechanical cryocoolers are preferred over passive ones. The reason is that passive radiators induce constraints on satellite orbit and attitude.

Distributed optical fibre sensors (DOFS) are highly suitable for monitoring temperature, vibration and strain using physical principles such as Raman, Rayleigh and Brillouin backscatter. They convert a standard telecom infrastructure to a sensor network providing thousands of virtual sensors per km using the intrinsic light/glass interaction during propagation.