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Redisch, W. N.

Publications and source records attributed to Redisch, W. N..

13 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1978

The search and rescue satellite mission - A basis for international cooperation

The use of geostationary and polar-orbiting satellites to monitor and locate signals of the Emergency Locator Transmitter (ELT) and Emergency Position Indicating Radio Beacon (EPIB) of general aviation aircraft and inspected marine vessels respectively is described. The joint U.S. Canada/France SARSAT demonstration program will require a minimum of four minutes of mutual visibility of distress transmitter, local user terminal and satellite to obtain a location by Doppler tracking. The program consisting of placing instrumentation on-board three of the Tiros-N series of NOAA operational satellites is attracting interest also from other countries including the USSR, Norway, Australia, and Japan.

Redisch, W. N.↗
NASA NTRS1977

Satellite communication for public services

Public service programs using NASA's ATS-6 and CTS satellites are discussed. Examples include the ATS-6 Health and Education Telecommunications experimental program and the use of CTS to enable students in one university to take courses presented at another distant university. Possible applications of satellite communication systems to several areas of public service are described, and economic and political obstacles hindering the implementation of these programs are considered. It is suggested that a federally sponsored program demonstrating the utility of satellites accomodating a large number of small terminals is needed to encourage commercial satellite operations.

Cooper, R. S.↗
NASA NTRS1976

Satellite communications at the Goddard Space Flight Center

Starting with the 1960 Delta launch of the first Echo satellite, NASA's Goddard Space Flight Center (GSFC) became one of the pioneers in satellite communications. Attention is given to the project Syncom, the Applications Technology Satellite (ATS) program, the ATS-6 project, and current GSFC efforts. After the decision announced in January of 1973 that NASA would phase out of communications satellite programs, the communications effort at GSFC concentrates on the operation of ATS spacecraft in orbit, experiments in the 12- to 14 GHz frequency band, and advanced communications research.

Clark, J. F.↗
NASA NTRS1975

ATS-6 - Description and performance

The Applications Technology Satellite-6 embodies a geosynchronous technology that is sensitive enough to receive signals from simple inexpensive earth-based terminals and is powerful enough to relay color television and other high-quality signals to these terminals. This was accomplished by deploying a 9.1-m parabolic reflector antenna in space, by performing precision attitude maneuvers on commands from the earth to point the reflector to selected spots on the earth's surface, and by providing communications links and necessary power to receive and rebroadcast signals transmitted from the ground. All major objectives of the ATS program have been satisfied, with specifications being met or exceeded.

Redisch, W. N.↗
NASA NTRS1975

ATS-6 description

Basic design features of Applications Technology Satellite-6 (ATS-6) are discussed, and a variety of experiments carried out with the satellite is described. The 9.1 m reflector is a furlable 48-rib design. The earth viewing module housing most of the electronics is connected to the reflector by an A-frame truss made of graphic fiber reinforced plastic with excellent dimensional stability over a wide temperature range. The solar arrays, extended beyond the diameter of the reflector, are fixed hemi-cylinders consisting of 16 flat panels each. The communications system is an integrated multifrequency RF repeater capable of receiving up to 3 signals in any of 4 frequency bands (C, S, L, VHF) and retransmitting them on any desired frequency in 4 frequency bands (C, S, L, UHF). Results of the Tracking and Data Relay Experiment with GEOS-3 are summarized. Accuracies of 0.1 to 0.2 deg have been maintained in the programmed mode of tracking using the ATS-6 Digital Operational Controller, and communications links for the relay of 1.56 kilobit telemetry data from GEOS and for acquisition of range and range rate data performed as predicted or better.

Redisch, W. N.↗
NASA NTRS1975

ATS-6 description

The major design features of the sixth Applications Technology Satellite (ATS-6) are discussed. The three-axis stabilized, geostationary satellite, launched in May 1974, features a 9.1 meter parabolic antenna permitting the use of low cost 3 meter ground terminals for the reception of direct broadcast high quality color television programming. The communication subsystem is an integrated multifrequency RF repeater capable of receiving up to three signals in C, S, L, and VHF bands and retransmitting them at any commanded frequency in C, S, L, and UHF bands. A summary of the experiments carried aboard ATS-6 is provided, and early results from the GEOS Tracking and Data Relay Experiment are presented.

Redisch, W. N.↗
NASA NTRS1974

ATS-6 spacecraft design/performance

A description is given of major program objectives and experiment requirements established for ATS-6. The ability to slew across the earth's disk in less than 30 min was needed to support tightly scheduled communication operations involving different parts of the earth. Two major experiments were developed which involve direct satellite relay of educational color television programs to simple ground receivers. Details of spacecraft configuration are discussed along with aspects of spacecraft ground testing. The ATS-6 was successfully launched on schedule from Cape Canaveral on May 30, 1974, with the aid of a Titan IIIC. The in-orbit performance of the spacecraft communication subsystem has been excellent.

Redisch, W. N.↗
NASA NTRS1972

Adaptive multibeam experiment for aeronautical and maritime services /AMEAMS/.

An experiment using NASA's ATS-G satellite was designed to provide essential data and field experience for the application of adaptive multiple satellite beam techniques to small mobile terminal communications system designs. Two approaches to the system were considered: an adaptive simultaneous multibeam mode and a hopped-beam mode. In the former case, both interbeam and intrabeam adaptive power management are used, while in the latter, beam energy is controlled through the use of time division techniques. The objectives of the experiment, design and implementation approaches, and potential applications are discussed.

Redisch, W. N.↗
NASA NTRS1971

Adaptive multisatellite systems for aeronautical services.

The use of satellite systems to provide operational communications and ATC services to aircraft flying the oceanic routes has been the subject of considerable interest recently. Since most of the link factors are functions of geometry and the aircraft traffic density varies with time, the satellite power needed to meet the communication demand varies considerably in an oceanic area as a function of both location and time. An adaptive system that tailors the use of system resources to the needs of the user can result in an additional system capacity improvement by a factor of between two and three. Results of studies conducted to date indicate that simple implementation of adaptive techniques in aeronautical satellite systems is feasible. Study is continuing in this area and on the application of satellite multibeam techniques to gain even further increase in capacity.

Bisaga, J. J.↗