Session
Technical Session IV: Commercial Communications And Remote Sensing
Abstract
ORBCOMM is a low cost, two-way data messaging system that uses a constellation of 36 spacecraft to provide global coverage for a wide variety of applications. Following an aggressive launch schedule, Orbital Sciences Corporation (Orbital) launched 26 spacecraft within 10 months to set up the constellation that is now providing global service to subscribers. As of August 1999, the constellation spacecraft have already accumulated over 30 spacecraft-years of on-orbit experience while demonstrating excellent in-flight performance. The ORBCOMM spacecraft design epitomizes the mass, power, and volume efficiencies of Orbital's MicroStar spacecraft platform. Unlike a single spacecraft mission, the ORBCOMM constellation provides a unique opportunity to assess the performance of multiple spacecraft at the same time. This paper presents pertinent flight data for key spacecraft subsystems with a focus on hardware performance. Beginning with the subsystem performance for a single spacecraft the analysis is then extended to the constellation level with an assessment of subsystem performance of multiple spacecraft over an extended period of time. The presented data demonstrates the successful design and operation of the MicroStar spacecraft platform, which constitute the basis for the ORBCOMM satellite constellation.
On-orbit Performance of the ORBCOMM Spacecraft Constellation
ORBCOMM is a low cost, two-way data messaging system that uses a constellation of 36 spacecraft to provide global coverage for a wide variety of applications. Following an aggressive launch schedule, Orbital Sciences Corporation (Orbital) launched 26 spacecraft within 10 months to set up the constellation that is now providing global service to subscribers. As of August 1999, the constellation spacecraft have already accumulated over 30 spacecraft-years of on-orbit experience while demonstrating excellent in-flight performance. The ORBCOMM spacecraft design epitomizes the mass, power, and volume efficiencies of Orbital's MicroStar spacecraft platform. Unlike a single spacecraft mission, the ORBCOMM constellation provides a unique opportunity to assess the performance of multiple spacecraft at the same time. This paper presents pertinent flight data for key spacecraft subsystems with a focus on hardware performance. Beginning with the subsystem performance for a single spacecraft the analysis is then extended to the constellation level with an assessment of subsystem performance of multiple spacecraft over an extended period of time. The presented data demonstrates the successful design and operation of the MicroStar spacecraft platform, which constitute the basis for the ORBCOMM satellite constellation.
