Unified Approach to Photon-Counting Microlaser Rangers, Transponders, and Altimeters

Geophysical surveys - 2001
John J. Degnan1
1Geoscience Technology Office, Code 920.3, NASA Goddard Space Flight Center, Greenbelt, USA

Tóm tắt

Unlike current manned systems, NASA's next generation SLR2000 Satellite Laser Ranging (SLR) station is fully autonomous, eye-safe, relatively compact and inexpensive, and, during daytime tracking, operates at signal-to-noise ratios several orders of magnitude below unity. Tiny, passivelyQ-switched microlasers generate ultra-short pulses with output energies on the order of 100 μJ at few kHz rates to achieve mm-levelranging precision to satellite altitudesof 20,000 km. Special ranging receivers, combined with Poisson statistical analysis of the received photon distribution, enable the system to rapidly and reliably identify and extract the single photon laser echoes from the solar background. The enhanced rate of return, combined with a uniform signal strength, can actually drive down both systematic and random range errors. The new SLR2000 technology has already spawned exciting new applications. Compact microlaser altimeters, capable of mapping the surface of a planet or other celestial body at multikilohertz rates, is one such application, and a high altitude, airborne version is currently being developed under NASA's Instrument Incubator Program. Interplanetary microlaser transponders would be capable of performing decimeter ranging or subnanosecond time transfer to spacecraft throughout the inner Solar System, resulting in improved knowledge of planetary motions and librations and enhanced General Relativity experiments.

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Tài liệu tham khảo

Abbott, R. and Shelus, P.: 1973, Laser observations of the Moon: Identification and construction of normal points for 1969–1971, The Astronomical Journal 78, 784–793.

Degnan, J.: 1993, Millimeter accuracy satellite laser ranging: A review, in D. E. Smith and D. L. Turcotte (eds), Contributions of Space Geodesy to Geodynamics: Technology, AGU Geodynamics Series, Volume 25, pp. 133–162.

Degnan, J., 1996, Compact laser transponders for interplanetary ranging and time transfer, Proceedings 10th International Workshop on Laser Ranging, Shanghai, China, November 11–15, pp. 24–31.

Degnan, J. and McGarry, J.: 1997, SLR2000: Eyesafe and autonomous satellite laser ranging at kilohertz rates, SPIE Vol 3218, Laser Radar Ranging and Atmospheric Lidar Techniques, London, UK, Sept. 24–26, pp. 63–77.

Degnan, J.: 1998, SLR2000 Project: Engineering Overview and Status, Proceedings 11th International Workshop on Laser Ranging, Deggendorf, Germany, Sept. 21–25, pp. 389–398.

Degnan, J., McGarry, J., Dabney, P., Zagwodzki, T., Tierney, M., and Weatherley, M.: 1998, Design and test of a breadboard interplanetary laser transponder, Proceedings 11th International Workshop on laser Ranging, Deggendorf, Germany, Sept. 21–25, pp. 716–728.

Degnan, J. and McGarry, J.: 1998, Feasibility study of multikilohertz spaceborne microlaser altimeters, European Geophysical Society (EGS) Symposium, Nice, France, April 20–24. Annales Geophysicae, Part 1, Society Symposia, Solid Earth Geophysics and Geodesy, Supplement 1 to Volume 16, p. C379 (Abstract only).

Degnan, J., McGarry, J., Zagwodzki, J., Dabney, P., Geiger, J., Chabot, R., Steggerda, C., Marzouk, J., and Chu, A.: 2001, Design and performance of an airborne multikilohertz photon-counting microlaser altimeter, Int. Archives of Photogrammetry and Remote Sensing, Vol. XXXIV-3/W4, Annapolis, MD, 22–24 Oct. 2001, pp. 9–16.

Degnan, J.: 2002a, Photon-counting multikilohertz microlaser altimeters for airborne and spaceborne topographic measurements, J. Geodynamics, in press.

Degnan, J.: 2002b, Asynchronous laser transponders for precise interplanetary ranging and time transfer, J. Geodynamics, in press.

Priedhorsky, W., Smith, R., and Ho, C.: 1996, Laser ranging and mapping with a photon counting detector, Applied Optics 35, 441–452.

Titterton, P., Sweeney, H., and Leonard, D.: 1998, System/usage impact of operating the SLR2000 at 2 kHz, Proceedings 11th International Workshop on Laser Ranging, Deggendorf, Germany. September 21–25, pp. 426–437.

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Geophysical surveys

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