The Compact Ocean Wind Vector Radiometer: A New Class of Low-Cost Conically Scanning Satellite Microwave Radiometer System
The enabling features include the use of a single multi-frequency feed horn permitting a simple antenna rotating about the feed axis, as opposed to having to spin the entire radiometer system; internal calibration sources which enable fully polarimetric calibration and eliminate the need for an external warm load and cold sky reflector simplifying the mechanical design and enabling a complete 360 degree scan; and a compact highly integrated MMIC polarimetric combining receiver implementation, lowering the system mass and power which in turn makes the system well suited for deployment on smaller class, lower cost satellites.
This paper will give a description of the COWVR system and an overview of the technology demonstration mission. We will discuss the unique processing techniques required for this system, including Electronic Polarization Basis Rotation to transfer the polarimetric measurements from the instrument frame to the Earth frame and describe how this actually improves the sensor calibration compared to the more traditional sensor design approach. We will also discuss the wind vector retrieval performance improvement enabled by the two-look (fore and aft) observations from the 360 degree scan. Finally, we will discuss how the COWVR design is scalable to a wider range of frequencies from 6-183 GHz enabling a class of low-cost operational sensors that match the current capability provided by sensors such as SSMI/S, AMSR-2, WindSat and GMI.