Abstract

The Surface-Water Ocean Topography (SWOT) mission, currently in development at NASA?s Jet Propulsion Laboratory (JPL), will employ the Ka-band radar interferometer (KaRIn) to characterize the ocean's height at the unprecedented spatial resolution of 2 km and is designed to provide a global inventory of significant terrestrial water bodies [area g(250 m)2] and rivers (width g50-100 m). The key enabling technology for this instrument is a pair of large, deployable antennas that form the interferometer. This article describes the development of the largest reflectarray antenna currently in process for a spaceflight application: a 5 ? 0.26-m offset-fed reflectarray antenna with a 4.37-m focal length. It details critical aspects of the development, including the radio-frequency (RF) design and analysis, fabrication, and measurement, and discusses unique requirements imposed by the interferometer that resulted in significant design and verification challenges. Flight-hardware measurements demonstrated a gain of approximately 49.5 dB, corresponding to an efficiency of 52%, and an azimuth beamwidth of 0.105?, with a beam-pointing knowledge of 5 millidegrees. Accurate characterization of these antenna-performance parameters is critical to the success of the KaRIn instrument.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.