Radar and lidar measurement principle

As the weather radar rotates around its axis 360° in a sweep, it transmits microwave pulses into the atmosphere and receives signals reflected off hydrometeors, such as rain, hail, or snow. Similarly, the light emitted by a WindCube Scan lidar is scattered on the aerosols present in the atmosphere. After a sweep, the radar or lidar usually changes its elevation and starts a new sweep.

The reflection measurements are sorted into radar bins or lidar range gates. They are single samples of weather data detected at a known direction, altitude, and distance from the device site.

Volumes, a complete set of raw measurement data collected during sweeps, are used to calculate a model of the atmosphere. The maximum volume is half of a sphere (from 0° elevation upwards), but other shapes are more typical.