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This status-report of the Wettzell Laser Ranging System (WLRS) gives an overview of its set up and the developments necessary to make the system operational.
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The Naval Research Laboratory proposed the Space Surveillance System for detecting, tracking, and orbit predicting of non radiating satellites. The Advanced Research Projects Agency has supported a feasibility experiment as Phase ...
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The Naval Research Laboratory proposed the Space Surveillance System for detecting, tracking, and orbit predicting of non radiating satellites. The Advanced Research Projects Agency has supported a feasibility experiment as Phase I, which has been completed. Further research and development in the area covered by this System are proceeding. Currently this System provides the only operational capability the Country has to detect noncooperating unannounced satellites. The performance of the experimental system on typical satellites is illustrated. Coverage extends to about 450 statute miles in height on one- square-meter targets over limited sections of an east-west line. The second phase of the program, now in the development stage will provide coverage to a height of about 2500 miles with a probability of detection of 95 percent over the extent of the entire line from the east to the west coast. Also automatic processing of data is to be incorporated to provide a system suit- able for operational use. A fully operational system requires a second line to enable precise orbit determination in a single pass. A recommended location is on a line extending in a northwest-southeast direction across the United States. The flexibility of the system design permits extensions and additions of equipment and facilities to meet increased operational requirements.
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A complex system of spacecraft and ground tracking stations, as well as a constellation of satellites or spacecraft, has to be able to reliably withstand sudden environment changes, resource fluctuations, dynamic resource configur...
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A complex system of spacecraft and ground tracking stations, as well as a constellation of satellites or spacecraft, has to be able to reliably withstand sudden environment changes, resource fluctuations, dynamic resource configuration, limited communication bandwidth, etc., while maintaining the consistency of the system as a whole. It is not known in advance when a change in the environment might occur or when a particular exchange will happen. A higher degree of sophistication for the communication mechanisms between different parts of the system is required. The actual behavior has to be determined while the system is performing and the course of action can be decided at the individual level. Under such circumstances, the solution will highly benefit from increased on-board and on the ground adaptability and autonomy. An evolvable architecture based on intelligent agents that communicate and cooperate with each other can offer advantages in this direction. This paper presents an architecture of an evolvable agent-based system (software and software/hardware hybrids) as well as some plans for further implementation.
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摘要 :
A complex system of spacecraft and ground tracking stations, as well as a constellation of satellites or spacecraft, has to be able to reliably withstand sudden environment changes, resource fluctuations, dynamic resource configur...
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A complex system of spacecraft and ground tracking stations, as well as a constellation of satellites or spacecraft, has to be able to reliably withstand sudden environment changes, resource fluctuations, dynamic resource configuration, limited communication bandwidth, etc., while maintaining the consistency of the system as a whole. It is not known in advance when a change in the environment might occur or when a particular exchange will happen. A higher degree of sophistication for the communication mechanisms between different parts of the system is required. The actual behavior has to be determined while the system is performing and the course of action can be decided at the individual level. Under such circumstances, the solution will highly benefit from increased on-board and on the ground adaptability and autonomy. An evolvable architecture based on intelligent agents that communicate and cooperate with each other can offer advantages in this direction. This paper presents an architecture of an evolvable agent-based system (software and software/hardware hybrids) as well as some plans for further implementation.
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Geodetic information for NASA tracking stations and observation stations in the NASA Geodetic Satellites Program is documented. A Geodetic Data Sheet is provided for each station, giving the position of the station and describing ...
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Geodetic information for NASA tracking stations and observation stations in the NASA Geodetic Satellites Program is documented. A Geodetic Data Sheet is provided for each station, giving the position of the station and describing briefly how it was established. Geodetic positions and geocentric coordinates of these stations are tabulated on local or major geodetic datums, and on selected world geodetic systems when available information permits. Observation stations in the NASA Geodetic Satellites Program and stations participating in the National Geodetic Satellite Program are identified. Station positions of these facilities are given on local or preferred major datums, and on the Modified Mercury Datum 1968.
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