title: Digital-beamforming array antenna technologies for future ocean-observing satellite missions
abstract: Existing passive microwave radiometers that are used for ocean observations are limited in spatial resolution and geographic coverage, due to the limitations of traditional antenna technologies using mechanically-scanning reflectors and horn-type feeds. Future ocean observation missions call for new solutions, such as digitally-beamforming array feeds (DBAFs) as well as stationary and more complex reflectors. Our studies demonstrate that DBAFs can overcome the physically fundamental limitations 