The work principles of the atmosphere profile synthesis detecting system (the wind profiler and RASS radar) are introduced. The application of the detecting technology in the upper air abroad is discussed by giving some examples. The system can be used to calculate humidity profiles, detect heat and dynamical structures of fronts and vertical wind structure, and diagnose the planetary boundary layer and rainfall cloud systems in tropic regions. The methods are proposed for calculating humidity profiles in the range of 0.2 km to 2.2 km in altitude by means of the wind profile/RASS data from the Feixi observing experiment site in Anhui Province in Summer 2002.