  Satellite communications (SatCom) are crucial for global connectivity,
especially in the era of emerging technologies like 6G and narrowing the
digital divide. Traditional SatCom systems struggle with efficient resource
management due to static multibeam configurations, hindering quality of service
(QoS) amidst dynamic traffic demands. This paper introduces an innovative
solution - real-time adaptive beamforming on multibeam satellites with
software-defined payloads in geostationary orbit (GEO). Utilizing a Direct
Radiating Array (DRA) with circular polarization in the 17.7 - 20.2 GHz band,
the paper outlines DRA design and a supervised learning-based algorithm for
on-board beamforming. This adaptive approach not only meets precise beam
projection needs but also dynamically adjusts beamwidth, minimizes sidelobe
levels (SLL), and optimizes effective isotropic radiated power (EIRP).

Signal Processing