LEO to GEO Communications from Concept to On Orbit Mission Success

NOAA (National Oceanic and Atmospheric Administration) and the NOW (Nano Orbital Workshop) project at NASA Ames Research Center collaborated to prove that the GOES satellites can communicate with spacecraft in LEO and provide full-time connectivity to the ground (LEO to Geo to ground). The DCS (Data Collection System) provides a low-speed relay from remote sensors using the NOAA Geostationary Operational Environmental Satellite (GOES). The DCS has provided essential data since 1975. Meteorology, oceanography, hydrology, ecology, and remote sensing of earth resources are some of the applications that depend on the DCS. There are currently about 3000 DCS users.

The NOW project develops and launches the TechEdSat series of CubeSats.

The European Space Agency (ESA) Meteosat and the Japanese Space agencies (JAXA) Himawari have analog systems to GOES DCS. A satellite in any LEO orbit, with access to all three systems, would have a low bandwidth full-time, real-time link back to Earth. Normally, a satellite would have to wait until over an earth station to send data.

A full-time link (even a low bandwidth one) would be useful for reporting internal spacecraft failures, or near-earth objects, forest fires, earthquakes, tsunamis, solar storms, and other hazards requiring immediate attention.

The hallmarks of the TechEdSat/NOAA collaboration are:
1. Low cost
2. Stepwise development
3. Informal cooperation
4. Leverage of the experience of the TechEdSat team and the innovative
technologies they have developed
5. Close cooperation from the board designers at Microcom design Inc.

Three TechEdSat (T) missions were launched with GOES DCS experiments. The third (TechEdSat-11) was a complete success, and, able to communicate using either GOES or the European Meteosat.

Challenges include spacecraft position control, doppler mitigation, power distribution, and complex on-orbit testing.

We will describe the technical details of the DCS system and the TechEdSat payload.