Author: Edmond M. DewanPublisher:
ISBN:
Category : Atmospheric turbulence
Languages : en
Pages : 56
Book Description
A Model for C2n (optical Turbulence) Profiles Using Radiosonde Data
Author: Edmond M. DewanPublisher:
ISBN:
Category : Atmospheric turbulence
Languages : en
Pages : 56
Book Description
˜Aœ model for Cn (optical turbulence) profiles using radiosonde data
Author: Free-Space Laser Communications
Author: Arun K. MajumdarPublisher: Springer Science & Business Media
ISBN: 0387286772
Category : Science
Languages : en
Pages : 429
Book Description
This is a comprehensive tutorial on the emerging technology of free-space laser communications (FSLC). The book offers an all-inclusive source of information on the basics of FSLC, and a review of state-of-the-art technologies. Coverage includes atmospheric effects for laser propagation and FSLC systems performance and design. Free-Space Laser Communications is a valuable resource for engineers, scientists and students interested in laser communication systems designed for the atmospheric optical channel.
Scientific and Technical Aerospace Reports
Author: Optical Turbulence Forecasting
Author: Edmond M. DewanPublisher:
ISBN:
Category : Atmospheric turbulence
Languages : en
Pages : 76
Book Description
This report is a tutorial on the effects of atmospheric turbulence upon systems which rely upon the propagation of LASER beams. In addition to providing a simplified presentation of turbulence theory and optical effects, it describes the state of the art of the new technique of radiosonde estimation of index of refraction fluctuations. Suggestions are given for future research which will help to answer current Air Force needs. The feasibility of some laser systems will depend upon the value of r0, the coherence length (which is related to “C2n” which in turn is related to the degree of turbulence). At present, the statistics of “r0” are inadequate.
Atmospheric Turbulence Characteristics Inferred from Optical Measurements at Lick Observatory
Author: Lawrence William BradfordPublisher:
ISBN:
Category : Atmospheric turbulence
Languages : en
Pages : 548
Book Description
Solar Heating Effects on Balloon-Borne Microthermal Probes for the Airborne Laser Program
Author: Daniel J. RichardsonPublisher:
ISBN: 9781423569558
Category :
Languages : en
Pages : 107
Book Description
Atmospheric optical turbulence induces phase fluctuations in a propagating electromagnetic wave. The resulting degradation in coherence limits the capability of any laser, target acquisition, or surveillance system. Past data collection methods for the parameterization of atmospheric turbulence profiles, in support of critical Theater Ballistic Missile Defense (TBM) systems, from ground level to 30 km, have depended on meteorological balloon- thermosonde systems, probes carried on the U.S. Air Force Argus aircraft, as well as radar and optical measurements. The balloon and aircraft systems measure temperature fluctuations and compute the temperature structure function, CT2 and the related index of refraction structure parameter, Cn2. It has recently become critical to explain why turbulence profiles from daytime thermosonde data consistently show a two order of magnitude increase over that taken during the night, primarily between 12-20 km. This thesis analyzed the TSI 3.8 micron platinum coated tungsten thermosonde probe used by the USAF Research Laboratory (AFRL) to quantity the magnitude of the solar heating and to investigate other heat transfer mechanisms in the probe. A model of the thin wire probe was developed to identity each of the contributions to the temperature error and its significance. Experimental measurements where collected to verify most aspects of the final model. We found that the sun induces a temperature rise in the TSI 3.8 micron fine wire probe, during the day, that can vary from near zero to 0. 175 K. It is strongly dependent on probe orientation with respect to the sun and on variations in the air flow over the probe. This then causes an apparent increase by two orders of magnitude in the daytime measurements of the optical turbulence parameters CT2 and Cn2.
Journal of the Optical Society of America
Author: Digest of Technical Papers
Author: Publisher:
ISBN:
Category : Computer storage devices
Languages : en
Pages : 206
Book Description
Government Reports Annual Index
Author: Publisher:
ISBN:
Category : Government reports announcements & index
Languages : en
Pages : 1662
Book Description