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Development of an All-Fiber Coherent Laser Radar for Precision Range and Velocity Measurements

Published online by Cambridge University Press:  01 February 2011

Diego Pierrottet
Affiliation:
Coherent Applications, Inc., Hampton VA, 23669
Farzin Amzajerdian
Affiliation:
NASA Langley Research Center, Hampton VA 23681
Frank Peri
Affiliation:
NASA Langley Research Center, Hampton VA 23681
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Abstract

An all-fiber coherent laser radar system capable of high-resolution range and line of sight velocity measurements is under development with a goal to aid NASA's new Space Exploration initiative for manned and robotic missions to the Moon and Mars. Precision range and velocity data are key parameters to navigating planetary landing pods to the pre-selected site and achieving autonomous safe soft-landing. By employing a combination of optical heterodyne and linear frequency modulation techniques [1-3] and utilizing state-of-the-art fiber optic technologies, highly efficient, compact and reliable laser radar suitable for operation in a space environment is being developed.

The all-fiber coherent laser radar has several important advantages over more conventional pulsed laser altimeters or range finders. One of the advantages of the coherent laser radar is its ability to directly measure the platform velocity by extracting the Doppler shift generated by the platform motion. The Doppler velocity measurement is about two orders of magnitude more accurate than the velocity estimates obtained by laser altimeters using the rate of change in range [4]. Another advantage is continuous-wave operation that allows the use of highly efficient and reliable commercial off-the-shelf fiber optic telecommunication components. This paper will describe the design and operation of this laser radar sensor and discuss its projected performance. A laboratory breadboard system has already been developed as a step toward a flight prototype. The experimental data representing the potentials of this laser radar system will be reported.

Type
Research Article
Copyright
Copyright © Materials Research Society 2005

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References

1 Skolnik, M. I.Introduction to Radar Systems” 2nd ed., McGraw-Hill Book Company, New York, (1980).Google Scholar
2 Saunders, W. K.Post War Developments in Continuous-Wave and Frequency Modulated Radar,” IRE Trans., vol ANE-8, pp. 719, March, (1961).Google Scholar
3 Kachelmyer, A. L.Range-Doppler imaging: wave-forms and receiver design,” Proc. SPIE, vol. 999, pp., 138161, (1988).Google Scholar
4 Jelalian, A. V.Laser Radar Systems,” Artech House, Massachusetts, (1992).Google Scholar
5 Space Studies Board, National Research Council, New Frontiers in the Solar System – An Integrated Exploration Strategy, National Academy Presss, Washington, D.C., (2003).Google Scholar
6 Golombek, M. P. Cook, R. A. Economou, T. Folkner, W. M. Haldemann, A. F. C. Kallemeyn, P. H. Knudsen, J. M. Manning, R. M. Moore, H. J. Parker, T. J. Rieder, R. Schofield, J. T. Smith, P. H. and Vaughan, R. M.Overview of the Mars Pathfinder Mission and Assessment of Landing Site Predictions,” Science Magazine, 278: 17431748, December 5, (1997).Google Scholar
7 Wong, E. C. and Masciarelli, J. P. “Autonomous Guidance and Control Design for Hazard Avoidance and Safe Landing on Mars”, AIAA Atmospheric Flight Mechanics Conference and Exhibit 5-8, 4619, Monterey, California, August, (2002).Google Scholar
8 Karlsson, C. J. and Olson, F. A.Linearization of the frequency sweep of a frequency-modulated continuous-wave semiconductor laser and the resulting ranging performanceApp. Opt. Vol. 38, No. 15, pp 33763386, (1999).Google Scholar