Rain radar system studies and hardware developments in Europe

Describes the work that has been accomplished during the last 4 years by ALCATEL ESPACE, Toulouse, France, in the field of rain radar systems and instrument definition. The first topic concerns the BEST project initiated by the French Space Agency. ALCATEL was responsible for the definition of the radar instrument: a 14 GHz pulse compression radar, using a 4.1 m×4.7 m reflector antenna and a 300 W peak power TWTA. The second study was funded by the European Space Agency in 1991 and led to the definition and comparison of two advanced rain radar concepts: a dual-frequency radar operating at 24 and 35 GHz, and a dual-beam radar operating at 24 GHz and achieving a stereoscopic observation of the rain cells. That work was followed by a breadboarding study, which is still in progress now. The main objective is to build an all digital pulse compression subsystem for a rain radar, capable of -60 dB compressed pulse side lobe ratio