1290rwpprecipspec (a0)

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.

雷达风廓线仪/无线电声学探测系统（radar wind profiler/radio acoustic sounding system，RWP/RASS）设有915兆赫版本（供美国境内部署使用）与1290兆赫版本（供海外部署使用），可在标称0.1千米至5千米的区间内测量风廓线与后向散射信号强度，并在0.1千米至2.5千米的区间内测量大气虚温廓线。不过ARM已不再运营该系统的RASS子系统。RWP可向最多五个方向向大气发射电磁能量，其中四个分别在相互对立的垂直平面内倾斜，另一个沿垂直方向，并测量后向散射能量的强度与频率。通过对返回信号的多普勒频移进行计算，即可推演出大气风廓线。