Control and telemetry signal communication system for geostationary satellites

DETAILED DESCRIPTION Briefly, this invention contemplates the provision of a geosynchronous satellite control and telemetry communication system in which branch modules distributed throughout the satellite serially interface clusters of control and/or analog nodes to the central command and data handling processor.
Each branch module is connected to the central command and data handling processor by a serial data channel; in a preferred embodiment of the invention the serial data channel is a lightweight, shielded, twisted wire pair.
The branch modules are physically located close to the control/telemetry nodes for which they serve as interfaces to the central command and data handling processor and where appropriate are integrated into the satellite subsystems themselves.
Each branch module responds to data commands issued by the central command and data handling processor over the twisted wire pair connected to the module.
The central command and data handling processor is programmed to implement a system time line, issuing a recurring series of commands to the branch modules.
Upon receipt of a command from the central command and data handling processor, the branch module decodes the command, carries out the commanded action by generating, or sampling, one or more signals at its node interface, and responds back to the central command and data handling processor with the node status.
The central command and data handling processor then issues additional commands to the same branch module or moves on to another branch module so that the central flight computer addresses all critical control points and telemetry points during one system cycle.
In a preferred embodiment of the invention, the branch module includes a dual sided, hybrid assembly, with digital and analog integrated circuits mounted on one side of a wiring substrate and oscillator and passive components mounted on the other side.
The module has a single d.
c.
power input, and additional voltages needed to process analog signal inputs are generated by the module