Brownout, the loss of visibility caused by dust resultant of helicopter downwash, is a factor in the large majority of military helicopter accidents. As terahertz radiation readily propagates through the associated dust aerosols and is attenuated by atmospheric water vapor within short distances, it can provide low-profile imaging that improves effective pilot visibility. In order to model this application of terahertz imaging, it is necessary to determine the optical properties of obscurants at these frequencies. We present here a method of empirical calculation and experimental measurement of the complex refractive index of the obscuring aerosols. Results derived from terahertz time-domain spectral measurements are incorporated into the AFIT CDE Laser Environmental Effects Definition and Reference (LEEDR) software.
Abstract ©2012 Optical Society of America
Article
A Technique to Measure Optical Properties of Brownout Clouds for Modeling Terahertz Propagation
Applied Optics
Document Type
Article
Publication Date
6-1-2012
Disciplines
Abstract
DOI
10.1364/AO.51.003605
Citation Information
Steven T. Fiorino, Jason A. Deibel, Phillip M. Grice, Markus H. Novak, Julian Spinoza, Lindsay Owens, and Satya Ganti, "A technique to measure optical properties of brownout clouds for modeling terahertz propagation," Appl. Opt. 51, 3605-3613 (2012). https://doi.org/10.1364/AO.51.003605
The "Link to Full Text" button on this page loads the open access article version of record, hosted at OSA. The publisher retains permissions to re-use and distribute this article.