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Pinck, Deborah

Publications and source records attributed to Pinck, Deborah.

Mobile Propagation Results from Using the ACTS Mobile Terminal

NASA's Advanced Communications Technology Satellite (ACTS) provides an ideal spaced-based platform for analyzing the Ka-band mobile satellite channel. This paper reports on the results of the Ka-band mobile propagation analysis campaign using the ACTS Mobile Terminal (AMT) developed by the Jet Propulsion Laboratory (JPL). The objectives of the mobile propagation experiments were to measure and analyze the fading characteristics of the Ka-band channel. The analysis involved examining pilot tone tests in three environments: lightly shadowed suburban, moderately shadowed suburban, and heavily shadowed suburban. The results indicate that Ka-band pilot tones experience significant multipath and fading effects. It may be possible to design link margins to provide reliable service for the lightly shadowed suburban environment at Ka-band. However, for areas with moderate and heavy shadowing, the link margin required to realize reliable communications with 99% availability is excessive (26 dB for moderate shadowing, and greater then 30 dB for heavy shadowing). An alternate approach would be to use shadowing/fading countermeasures (e.g., interleaved error control coding and antenna diversity). Such mitigation techniques, necessary for reliable Ka-band mobile communication within a suburban environment, are currently being considered within the NASA program.

Pinck, Deborah↗

Internetworking satellite and local exchange networks for personal communications applications

The demand for personal communications services has shown unprecedented growth, and the next decade and beyond promise an era in which the needs for ubiquitous, transparent and personalized access to information will continue to expand in both scale and scope. The exchange of personalized information is growing from two-way voice to include data communications, electronic messaging and information services, image transfer, video, and interactive multimedia. The emergence of new land-based and satellite-based wireless networks illustrates the expanding scale and trend toward globalization and the need to establish new local exchange and exchange access services to meet the communications needs of people on the move. An important issue is to identify the roles that satellite networking can play in meeting these new communications needs. The unique capabilities of satellites, in providing coverage to large geographic areas, reaching widely dispersed users, for position location determination, and in offering broadcast and multicast services, can complement and extend the capabilities of terrestrial networks. As an initial step in exploring the opportunities afforded by the merger of satellite-based and land-based networks, several experiments utilizing the NASA ACTS satellite and the public switched local exchange network were undertaken to demonstrate the use of satellites in the delivery of personal communications services.

Wolff, Richard S.↗

Integration of mobile satellite and cellular systems

By integrating the ground based infrastructure component of a mobile satellite system with the infrastructure systems of terrestrial 800 MHz cellular service providers, a seamless network of universal coverage can be established. Users equipped for both cellular and satellite service can take advantage of a number of features made possible by such integration, including seamless handoff and universal roaming. To provide maximum benefit at lowest posible cost, the means by which these systems are integrated must be carefully considered. Mobile satellite hub stations must be configured to efficiently interface with cellular Mobile Telephone Switching Offices (MTSO's), and cost effective mobile units that provide both cellular and satellite capability must be developed.

Drucker, Elliott H.↗