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Shepphird, F. H.

Publications and source records attributed to Shepphird, F. H..

Space station needs, attributes, and architectural options: Brief analysis

A baseline set of model missions is thoroughly characterized in terms of support requirements, demands on the Space Station, operating regimes, payload properties, and statements of the mission goals and objectives. This baseline is a representative set of mission requirements covering the most likely extent of space station support requirements from which architectural options can be constructed and exercised. The baseline set of 90 missions are assessed collectively and individually in terms of the economic, performance, and social benefits.

Shepphird, F. H.

Global services systems - Space communication

The requirements projected to the year 2000 for space-based global service systems, including both personal communications and innovative services, are developed based on historic trends and anticipated worldwide demographic and economic growth patterns. The growing demands appear to be best satisfied by developing larger, more sophisticated space systems in order to reduce the size, complexity, and expense of ground terminals. The availability of low-cost ground terminals will, in turn, further stimulate the generation of new services and new customers.

Shepphird, F. H.

Requirements for a geosynchronous information services platform

The requirements projected to the year 2000 for space-based communications facilities, including both personal communications and innovative services, are developed based upon anticipated demographic and economic growth for the seven major regions of the world. Projected growth requirements, when considered in light of operational factors such as orbit/spectrum crowding and the high investment costs of ground-based systems, suggest the need for new system concepts for communications. The concept of complexity inversion (placing high-cost systems in space and providing low-cost ground terminals to users) is examined and compared with the more conventional approach utiliizing land lines and extensive ground installations. The recommendation is made to develop the technology and capability to construct platforms in space, and the applicability of the Shuttle/Spacelab system in constructing large antenna systems in space is briefly considered.

Ness, H. C.