SBS system description

The essential engineering features and resulting operational capabilities of the Satellite Business Systems (SBS) network are presented. The major SBS earth station components are the port adapter system, the Satellite Communications Controller (SCC), the moniter and commerce system, the burst medium, and the radio frequency terminal; the main functions of these components are summarized. The SBS space segment includes the satellites, the Telemetry, Tracking and Command (TT&C) earth stations, and the satellite control facility. SBS will use two geographically separated TT&C stations for receiving telemetry from the satellites, for tracking to determine the orbital parameters, and for issuing commands to the satellites. The SBS Time Division Multiple Access (TDMA) burst architecture is designed to allocate transmission capacity among earth stations of a network according to the total network activity; this is achieved by assigning each earth station in the network an exclusive periodic time period during which only signals from the SCC appear in the transponder. The TDMA frame structure is given in detail.