Frequency coverage for weather and science missions in mm-wave and submm-wave radiometers is increasing and it is now possible for Omnisys to commercially offer receivers up to 1-2 THz. For frequencies exceeding 300 GHz, integrated MMIC technology is preferred as it enables performance improvements and allows for more efficient system level implementations.

A novel anti-reflection process was demonstrated which improves the quantum efficiency (QE) of a CMOS image sensor, with particular benefits at the ultraviolet (UV) and near infrared (NIR) ends of the electromagnetic spectrum. Also, the dark current and photoresponse non-uniformity (PRNU) were reduced to about 33% and 55%, respectively, of the values for a conventional control sensor. Spatial resolution seemed to be reduced in the NIR, as indicated by MTF measurements, but further investigations are required.

The supra-THz (>3 THz) bands have been recently proposed for low Earth orbit THz remote sounding missions such as LOCUS (Low-Cost Upper-atmosphere Sounder). In order to achieve coherent detection, heterodyne receivers at supra-THz frequencies are under development by integrating in a single waveguide cavity a Schottky based mixers fed by a Quantum Cascade Laser (QCL) as Local Oscillator (LO). Thanks to the QCL, enough LO power is available to drive the mixer.

Plastic marine litter is a very complex global environmental issue, with plastic litter at the sea surface representing only a small fraction of plastic entering the sea. In this respect, the BLUE project investigated the potential of diverse LIDAR techniques (backscatter, fluorescence, Raman) to address the detection of plastic litter not only floating on the sea surface, but also suspended in the first few metres under the surface, with also a focus on detecting microplastics and discriminating plastic from other types of litter. The approach adopted was four-fold:

For plastic detection, characterisation and tracking, we need rich spectral information, ideally hyperspectral data. We would like hyperspectral data up to short-wave infrared (2500 nm) and around 0.5 m ground sample distance. Neither of these characteristics are existent in current Earth observation missions, and will still be difficult to find in future Earth observation missions.