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13th International Laser Ranging
Workshop
"Toward Millimeter Accuracy"
Submitted
Abstracts
Atmospheric Correction and Multiwavelength Ranging (S. Riepl and E. Pavlis)
| Title | Primary Author |
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| Preliminary estimation of the atmospheric nonlinear frequency dispersion and absorption effects on the pulse SLR accuracy | Yuri Galkin |
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Moscow State Forest University Ruben A. Tatevian It is known, that the nonlinearity of the frequency-dependent refraction and absorption of air can evoke in additional errors of SLR, because of changes of the received ranging signal parameters are relatively of the standard calculation methods. Additional group delays, shift of a carrying frequency and her change in a receiving point of the Gaussian laser pulse for SLR are estimated. The estimation is made for "smooth" dispersion curve (just effective UV resonances) without effects of the atmospheric local resonances. It is noted that the shown effects are most important of the multi color SLR for Marini-Murray atmospheric model correction because of the effects depend on a laser ray elevation angle. Poster paper; received August 6, 2002 |
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| Biaxial Rayleigh- and Raman-LIDAR for applications in atmospheric sounding and SLR | Ulrich Schreiber |
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Technical University of Munich Florian Seitz, Franz Meyer Precise orbit determinations in SLR and LLR require corrections for the contribution of the atmosphere to the effective index of refraction. Despite the fact that the range measurements are obtained consistently, there is a discrepancy of approximately 4cm reported in the comparison between optical and microwave based range measurements for the same GPS satellite target. As a conclusion from earlier work, the knowledge of the water vapor content of the atmosphere at least for some selections of the operation wavelength seems important. To overcome the lack of sensitivity for the measurement of water vapour profiles in the Earth's troposphere by means of remote sensing a biaxial Rayleigh- and Raman LIDAR has been set up on the Fundamentalstation Wettzell, making use of the still existing equipment of a former SLR facility. By operating the station as a Rayleigh-LIDAR its geometrical characteristics and the overall sensitivity of this setup as a LIDAR system could be established and optimized. Observations in the spectral range of 607 nm and 660 nm are probing the troposphere for nitrogen and water molecules. By combining this information water vapor profiles of the lower troposphere were obtained. Oral paper; received August 14, 2002 |
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| Wavelength Dependence of Range Correction | David Arnold |
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94 Pierce Road The diffraction pattern of a retroreflector depends on the wavelength of the incident light. As a result, the range correction for an array with retroreflectors at different orientation angles will be different at each wavelength. This paper shows range correction matrices for LAGEOS at various wavelengths such as 355, 423.5, 847, and 1064 nanometers Oral paper; received August 22, 2002 |
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| Atmospheric Contribution to the Laser Ranging Jitter | Ivan Prochazka |
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Czech Technical University L. Kral The contribution of the atmospheric fluctuation - the seeing - to the laser ranging has been investigated. The beam propagation has been modeled using two independent approaches and models. The random component of the atmospheric propagation correction has been found to be well below 10 um for all seeing conditions, beam path geometry and wavelength. Oral paper; received August 22, 2002 |
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| Validation of Mapping Functions | Stefan Riepl |
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Bundesamt fuer Kartographie und Geodaesie David Ramirez, Cesar Guitano The present paper focuses on techniques, both numerical and experimental, which are currently used to validate mapping functions relating the zenith path delay correction to other angles of elevation. The paper concentrates on the application of two-color laser ranging data taken with the TIGO SLR module, aiming on a determination of the zenith path delay, as well as the utilization of numerical weather prediction data, which is applied to the estimation of horizontal refractivity gradients. Moreover a comparison of mapping functions with respect to their applicable spectrum of wavelengths is given using raytracing techniques. Oral paper; received August 23, 2002 |
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| Zimmerwald Dual-wavelength Operation: First Experiences | Werner Gurtner |
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Astronomical Institute Eugen Pop, Johannes Utzinger On August 14, 2002 Zimmerwald started to submit dual-wavelength SLR data collected on 423 and 846 nm using two Hamamatsu photomultipliers. The paper discusses the special hard- und software installations needed for the dual-wavelength operation and presents first results of acquired passes. Oral paper; received August 29, 2002 |
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| A Database of Atmospheric Refractivities from GPS Radio Occultations | Manuel de la Torre Juárez |
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Jet Propulsion Laboratory/Caltech George A. Hajj, Byron I Iijima, Chi O Ao, Anthony J. Mannucci,
Tom P. Yunck The launches of the CHAMP, SAC-C, and GRACE spacecraft have started a campaign of dense remote sensing of atmospheric refractivity profiles using GPS radio-occultations of the Earth's atmosphere. These data provide high resolution profiles of refractivities, up to the stratopause, which can be converted into geopotential heights, and atmospheric pressure and temperature as a function of geometric heights. These data are been made available to the community interested in operational applications. The characteristics and quality, of the data will be described. Oral paper; received September 03, 2002 |
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| Modification of Laser Ranging Equation | Xiong Yaoheng |
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Yunnan Observatory, Chinese Academy of Sciences Feng Hesheng The goal of this paper is to discuss the atmospheric turbulent effects on the laser beam of the laser ranging, especially for the lunar laser ranging. Considering the laser beam wander and spread caused by the atmospheric turbulence and the distribution of the laser beam, a new form of the laser ranging equation is given. That will guide us to do the real-time tilt compensation for the LLR. Oral paper; received September 11, 2002 |
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| Two-color laser ranging with the MLRO system | Giuseppe Bianco |
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Agenzia Spaziale Italiana T. Oldham, M. Bieneman, C. Clarke, V. Husson The Matera Laser Ranging Observatory (MLRO) has been developed and installed by Honeywell Technology Solutions Inc. at the Center for Space Geodesy "Giuseppe Colombo" (CGS) of the Italian Space Agency (ASI). The MLRO has built-in two-color ranging capability at 532 nm and 355 nm wavelengths with two receiving configurations: either a dual microchannel plate photomultiplier chain or a Hamamatsu streak camera. This presentation briefly outlines the system setup for two color ranging, and describes the first observational results obtained so far on ground targets and satellites. Oral paper; received September 17, 2002 |
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| Atmospheric Refraction at Optical Wavelengths: Problems and Solutions | Virgilio Mendes |
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Faculdade de Ciências da Universidade de Lisboa, Dep. de
Matemática Presented by: Erricos C. Pavlis Atmospheric refraction is an important accuracy-limiting factor in the application of satellite laser ranging (SLR) to high-accuracy applications. The modeling of that source of error in the analysis of SLR data comprises the determination of the delay in the zenith direction and subsequent projection to a given elevation angle, using a mapping function. Standard data analyses practices use the Marini-Murray model for both zenith delay determination and mapping. This model was tailored for a particular wavelength and is not suitable for all the wavelengths used in modern SLR systems. Using ray tracing though a large database of radiosonde data, we assess the zenith delay models and mapping functions currently available, we discuss the effect of using different types of input data to drive those models and the sensitivity of models and functions to changes in the wavelength and we give some recommendations towards a unification of practices and procedures in SLR data analysis. Oral paper; received September 17, 2002 |
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Last Updated:
September 17, 2002
