M. Christian Wallisch
The Aerospace Corporation, Maryland, United States
Keywords: Ka-band, LEO/GEO Satellite Communications, Radiation Hardening, Ground Segment
Ka-band has emerged as the foundation of high-throughput satellite communications in both LEO and GEO, yet its journey has been marked by critical technical challenges and evolutionary leaps in system design. This presentation traces the short but consequential history of Ka-band service, beginning with NASA's ACTS mission in 1993 and progressing through the failures of early adopters faced radiation effects and rain fade forcing a rapid pivot away from Ka-band feeder links. It examines how modern system—have overcome those limitations with hardened electronics, adaptive beamforming, and software-defined networks. The talk will also explore spectrum congestion, ground antenna sizing requirements, and lessons learned from operators, who now deploy global Ka-band infrastructure. Attendees will gain insight into pointing accuracy demands, radiation design considerations, and where Ka-band is heading next—from lunar relays to 6G convergence. The result is a compelling case study of how a once-fragile frequency band has become essential to global connectivity.