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Guion, William S.

Publications and source records attributed to Guion, William S..

Communications support for lunar missions using the TDRS II system

For several years NASA has been performing systems engineering analysis for lunar exploration scenarios with studies focused mainly on lunar communications, data systems and operations. Two basic earth-region communications architectures have been seriously considered, ground terminal architectures such as the deep space network (DSN) and geosynchronous relay satellites such as the tracking and data relay satellite II (TDRS II). An overview of TDRS II is given and lunar coverage, data rate capability, impacts to ground based elements, availability and operational scenarios are discussed. Development of the system is scheduled to begin soon and TDRS II can provide substantial support to early lunar missions without modification. Coverage and data rates are adequate and FLO missions can be supported. With enhancement nearly continuous coverage can be provided. TDRS II is a viable architecture and low cost option and should be considered as an alternative to the currently baselined DSN for precursor and possibly FLO missions.

Todd, Jacqueline

ATDRSS program overview

The authors provide an overview of the evolution of the Space Network from the Tracking and Data Relay Satellite System (TDRSS) structure of today to the Advanced TDRSS (ATDRSS) structure of the early 21st century. The TDRSS, with its White Sands Ground Terminal (WSGT), is an integral part of the overall NASA Space Network (SN) that will continue to evolve in the 1990s. Central ingredients of this evolution are the construction of the Second TDRSS Ground Terminal, an upgraded WSGT, and an ATDRSS follow-on to the current TDRSS that must be in operation by the late 1990s. Multiple ATDRSS architectural candidates have been identified, and a series of technical tradeoff assessments have been conducted. As a result of these assessments, key ingredients of a future ATDRSS baseline architecture have been defined and initial concepts for transition to an ATDRSS-oriented SN have been developed.

Jackson, Arthur H.

The Tracking and Data Relay Satellite System - The next decade

As currently envisioned, NASA's Tracking and Data Relay Satellite System (TDRSS) will support the tracking and telecommunications requirements of LEO user satellites until the late 1990s, when existing TDRSS satellites will reach the end of their service lives. Spacecraft replacement is conceived as inseparable from network expansion for the accommodation of user population growth and the improvement of user services. The objective is to achieve a cost-effective/low-risk transition from TDRSS to Advanced TDRSS without interruption of user support. Attention is presently given to Advanced TDRSS architectural candidates studied and the choices which have emerged through technical tradeoff assessments.

Guion, William S.