Prediction of IR transmission in a coastal Baltic environment: comparison between model predictions and measurements

摘要

A multinational campaign was organized by the NATO SET56 Group to assess transmission and propagation in coastal environments: the Validation Measurements of Propagation in IR and Radar (VAMPIRA) experiment. VAMPIRA was conducted in the Baltic, near Surendorf, Germany, from 27 March to 4 April 2004. During VAMPIRA, transmission was measured in the IR and the visible using a diversity of techniques. Among these, transmission was deduced from point-target tracking using blackbodies on board a boat. In this paper, VAMPIRA transmission measurements in the IR are compared with model predictions. We use MODTRAN for the calculation of gaseous attenuation in conjunction with aerosol extinction models currently available, namely: NAM (as in MODTRAN), WKDAERX (as in IRBLEM), ANAM3 and MEDEX. The various models are presented and put in their historical contexts. We found that under most stable situations encountered at VAMPIRA, the 3-mode models, NAM and WKD, provide better prediction than the 4-mode models ANAM3 and MEDEX.