RWP

The radar wind profiler/radio acoustic sounding system (RWP/RASS), available in 915-MHz (for U.S. deployments) and 1290-MHz (for foreign deployments), measures wind profiles and backscattered signal strength between (nominally) 0.1 km and 5 km and virtual temperature profiles between 0.1 km and 2.5 km. However, ARM no longer operates the RASS portion.

The RWP transmits electromagnetic energy into the atmosphere in as many as five directions (four tilted in opposing vertical planes and on vertical) and measures the strength and frequency of backscattered energy. Calculation of the Doppler shift of the returned signal allows calculation of the atmospheric wind profile.