Making All The Data Available Some Of The Time In Very Large Telemetry Volume Space Applications

Abstract

What do you do when your downlink telemetry needs outstrip your downlink bandwidth capability? The telemetry needed to support construction and operation of the largest, most complex engineering project ever undertaken, the International Space Station (ISS), already requires utilization of the full capacity of the downlink S-band capacity, yet there are additional systems and capabilities still to be added by NASA and the International Partners. The ISS Command and Telemetry Team has developed a method of swapping packets of telemetry that are intended for special operations, while simultaneously sending essential systems telemetry and less critical telemetry that is needed on a continuous basis. To support this attempt to “make available all of the data at least some of the time” the team developed concepts for grouping telemetry into families that would always be selected as a group and then created a set of metadata associated with these groups. This metadata is pre-defined to support automated selection and scrubbing of telemetry to correspond to major upgrades in the command and control software for the ISS. The new process will at least double the effective S-band downlink bandwidth. It will also provide automated selection, scrubbing, reporting and verification of telemetry selections.