Design, Integration, and Deployment of the TerreStar 18-meter Reflector

摘要

The TerreStar-1 spacecraft, designed and manufactured by Space Systems/Loral (SS/L), is the world's largest commercial satellite and will provide mobile data and voice communications throughout the U.S. and Canada. It communicates with very small earth terminals such as handheld PDA size cellular phones. It therefore must generate a high power flux density on the ground for a high quality link to be established, and achieve very high antenna gain to receive uplink signals. TerreStar-1 provides these capabilities by a combination of high power amplifiers and a large 18-meter aperture reflector designed and manufactured by Harris Corporation. TerreStar-1 was launched on July 1, 2009 and the 18-meter unfurlable reflector was successfully deployed on July 14, 2009. In-orbit testing confirms that the deployed antenna system functions as designed, and meets all communications performance requirements. This paper will briefly describe the TerreStar satellite and then discuss the design challenges that a large aperture reflector and its integration on the satellite create for the design team, and how those challenges were overcome. The details of the unfurlable reflector itself will not be covered in this paper. The focus will be on the reflector-to-spacecraft interface design, reflector system alignment, spacecraft integration, and on the analyses and ground testing performed to assure a successful on-orbit deployment. The mission team preparation for the on-orbit deployment will also be discussed. Summary data confirming successful on-orbit operation will be presented.