System Design and Subsystem Technology for a Future Spaceborne Cloud Radar

The 2007 Decadal Survey for the National Aeronautics and Space Administration recommended an Aerosol/Cloud/Ecosystems (ACE) mission with a new advanced cloud profiling radar. In this letter, we describe ACERAD, a radar design that could meet the goals for the ACE mission. ACERAD has 35 GHz (Ka-band) and 94 GHz (W-band) channels. It would scan at Ka-band and be nadir looking at W-band. The scanning antenna geometry is a classical Dragonian illuminated by a feed array; a reduced-size prototype of the antenna has been successfully fabricated and tested. ACERAD also uses a quasi-optical transmission line at W-band for low-loss routing of the signal from the transmitter to the antenna and from the antenna to the receiver. This letter briefly describes the ACERAD instrument design and test results for some of the major technologies needed for ACERAD implementation.