The ULEO study set put to evaluate the feasibility of quantum LIDAR setups for Earth Observation. LIDAR schemes based on quantum sensing with undetected light were in the centre of the study. But also alternative schemes shall be studied. 

The work involved the identification of critical performances and subsystems as well as the partially experimental checks of identified criticalities. Finally the feasibility shall be evaluated and required technology developments identified. 

The study explored several use cases of active remote sensing techniques based on quantum light states for Earth Observation and identified criticalities. 

A literature review was performed to identify the performance of subsystems based on current technology. First performance models were generated to estimate the signal to noise performance of quantum based LIDARs. Furthermore, the effect of air turbulences on quantum imaging with undetected light was tested with an experimental setup. 

Finally, the study evaluates the feasibility of different techniques. It also identifies open points and required technologies developments. The main conclusion is that the brightness of quantum light sources need to be increased and the delay line for the second photon (that does not probe the atmosphere) need to be further developed to become competitive to classical LIDAR sources.