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Mcgunigal, T. E.

Publications and source records attributed to Mcgunigal, T. E..

8 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1984

COSPAS/SARSAT: An overview

The SARSAT/COSPAS satellite network uses 121.5 and 406 MHz buoys to locate ships and aircraft in distress. The 121.5 MHz system, obligatory on many aircraft, gives localization to within 10 km, and, despite being subject to considerable radio interference and a poor signal to noise ratio, is responsible for saving nearly 200 lives. The 406 MHz location error is 2 km in 75% of cases, and less than or equal to 2 hr for 95% of cases in the worst conditions. It suffers however from interference from illegal broadcasts in the frequency band.

Mcgunigal, T. E.↗
NASA NTRS1979

Skylab-earth laser-beacon experiment - Results and analysis

Photographs of a ground-based laser beacon were taken by astronauts on board the Skylab spacecraft. Unexpected large and elliptical laser-beam images were recorded. The photographic results are presented and discussed in terms of possible atmospheric scattering mechanisms. Current beacon experiments with the Landsat spacecraft are also discussed.

Bufton, J. L.↗
NASA NTRS1975

Satellite laser ranging work at the Goddard Space Flight Center

Laser ranging systems, their range and accuracy capabilities, and planned improvements for future systems are discussed, the systems include one fixed and two mobile lasers ranging systems. They have demonstrated better than 10 cm accuracy both on a carefully surveyed ground range and in regular satellite ranging operations. They are capable of ranging to all currently launched retroreflector equipped satellites with the exception of Timation III. A third mobile system is discussed which will be accurate to better than 5 cm and will be capable of ranging to distant satellites such as Timation III and LAGEOS.

Mcgunigal, T. E.↗
NASA NTRS1975

Satellite laser ranging work at the Goddard Space Flight Center

The pulsed-laser satellite ranging systems presently being operated by the Goddard Space Flight Center are described along with their range and accuracy capabilities. The major subsystems are outlined, operation of the fixed system and the two mobile systems is discussed, and the performance of all three systems is evaluated. It is noted that these systems have an accuracy of better than 10 cm on a carefully surveyed range as well as in regular satellite ranging operations and are capable of ranging to all currently launched retroreflector-equipped satellites with the exception of Timation III. Future improvements discussed include a third mobile system which will be able to range distant satellites, such as Timation III, with an accuracy of better than 5 cm and the use of a frequency-doubled Nd:YAG laser in place of the ruby lasers now being employed.

Mcgunigal, T. E.↗
NASA NTRS1975

Satellite laser ranging work at the Goddard Space Flight Center

The paper describes the satellite laser ranging system at the Goddard Space Flight Center, its range and accuracy capabilities, and planned improvements for future systems. Major subsystems are described, including the laser, optical/mechanical, receiver, computer/software, timing, and laser data preprocessing subsystems. Operational considerations are examined, with attention given the mobile station layout, manpower requirements, and transportability. System performance is considered, with emphasis on system accuracy (calibration, stability, clock synchronization, atmospheric propagation correction) and range capability.

Mcgunigal, T. E.↗
NASA NTRS1971

A 10.6 micron laser-receiver RF subsystem

One of the problems inherent in the use of optical communication systems is the exceedingly high Doppler shift which can be expected. With the recent development of stable, linear, octavebandwidth, voltage-tunable oscillators, this problem has been solved. A laboratory tracking receiver which is capable of tracking a 1-GHz frequency shift at rates up to 12 MHz/s with subsequent coherent data demodulation was designed and tested. This work demonstrates that the design and fabrication of an RF subsystem, utilizing coherent demodulation of data, for wideband communications systems is now both feasible and practical.

Santarpia, D. E.↗