Three mobile and autonomous lidars built
Three compact EULIAA lidars have been built following a common design, with one IR system at 770 nm and two UV systems at 386 nm. All instruments share the same modular platform, multi‑FOV telescopes, Alexandrite laser technology and narrow‑band “solar‑blind” receivers, enabling identical operation concepts across IR and UV.
Autonomous and unattended operation
The systems are designed for fully autonomous 24/7 operation, including integrated weather station, ADS‑B aircraft surveillance, IR sky camera, motion sensor, UPS and remote interlocks. The UV configuration is eye‑safe for direct exposure times well beyond realistic aviation scenarios and has been approved for unattended operation in unrestricted airspace based on a full ERCS risk analysis.
Larger geographical coverage with multi‑FOV design
Each lidar uses three fixed fields-of-view: one vertical and two beams tilted by 30° in orthogonal azimuths. This geometry provides vertical and horizontal wind components from a single unit and enlarges the sampled volume, allowing future arrays of 10+ units to cover areas of >10,000 km².
Full daylight capability demonstrated (IR and UV)
Daylight‑capable operation has been demonstrated with both IR and UV systems using specially designed lens telescopes with solar‑rejection windows and active “anti‑seeing” cooling (patent pending). In combination with ultra‑narrow filters, the lidars is effectively solar‑blind in the Mie channel and strongly reduced in the solar background in the Rayleigh channel, enabling continuous measurements and stable performance even within about 2° distance to the Sun.
Long, maintenance‑free measurement series
The EULIAA IR lidar has accumulated more than 1,000 hours of autonomous operation, and the first EULIAA UV system more than 500 hours, without realignment or on‑site maintenance. Transports over ~3,000 km and month-long campaigns showed that alignment and performance of all subsystems remain stable over months.
High TRL demonstrated in European campaigns
Three major campaigns have been completed at sea level, in Arctic winter and in Mediterranean summer conditions, with ambient temperatures from about −15 to +40 °C. The systems survived thunderstorms with heavy rain, frost, and winds up to ~150 km/h in operation and >180 km/h in survival mode, confirming high technological readiness for real‑world deployments.
Unique atmospheric data from under‑sampled regions
EULIAA provides wind profiles up to ~25 km with unprecedented precision better than 1 m/s (and ~0.1 m/s up to ~20 km) and temperature profiles from about 15–50 km from Rayleigh scattering. At the same time, aerosol and cloud properties are retrieved via Mie backscatter and depolarization, including Polar Stratospheric Clouds, noctilucent clouds and high‑altitude aerosol layers such as rocket exhaust plumes. Although designed for the altitude range 2-50 km, the lidar is able to observe NLC at daytime on the summer mesopause regon > 84 km altitude. The IR-version is locked to the potassium resonance line which enables the observation of the metal layer at 80-100 km 24/7.
Advanced retrievals extend range and resolution
A novel signal‑decomposition lidar technique uses the known spectral chirp of each laser pulse to boost altitude, spectral and temporal resolution beyond the classical Fourier limit. This enables wind retrievals inside and above clouds, gravity‑wave studies and aerosol profiling with altitude resolutions down to tens of meters and integration times of only a few seconds.
Real‑time integration into European data systems
All lidars feed a real‑time processing chain that converts local level L0/L1 data into level L2/L3 products and standardized formats (NetCDF, BUFR) on the European Weather Cloud. Results are visualized on an interactive quicklook webpage and distributed to E‑PROFILE and the GEO Knowledge Hub, ensuring that EULIAA data are immediately usable by weather, climate and research communities.