The objective of this paper is to discuss the issues related to the use of Fade Mitigation Techniques (FMT) for the GEOCAST satellite system, considering both transparent and regenerative payloads. The main characteristics of the GEOCAST systems are presented first. Baseline link budgets are established both for the transparent return link and for the regenerative configurations. Then the FMTs designed for GEOCAST are presented. Theoretical performance of the FMTs and their practical implementation are described focusing on the FMT control loop design.Finally, simulation results for system performance with emphasis on physical layer, are presented both for transparent and regenerative configurations.

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