Share Email Print

Proceedings Paper

Marine atmospheric effects on electro-optical systems performance
Author(s): Juergen H. Richter; Herbert G. Hughes
Format Member Price Non-Member Price
PDF $14.40 $18.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

For the past twelve years, a coordinated tri-service effort has been underway in the United States Department of Defense to provide an atmospheric effects assessment capability for existing and planned electro-optical (E0) systems. This paper reviews the exploratory development effort in the US Navy. A key responsibility for the Navy was the development of marine aerosol models. An initial model, the Navy Aerosol Model (NAN), was developed, tested, and transitioned into LOWTRAN 6. A more comprehensive model, the Navy Oceanic Vertical Aerosol Model (NOVAM), has been formulated and is presently undergoing comprehensive evaluation and testing. Marine aerosols and their extinction properties are only one important factor in EO systems performance assessment. For many EO systems applications, an accurate knowledge of marine background radiances is required in addition to considering the effects of the intervening atmosphere. Accordingly, a capability was developed to estimate the apparent sea surface radiance for different sea states and meteorological conditions. Also, an empirical relationship was developed which directly relates apparent mean sea temperature to calculated mean sky temperature. In situ measurements of relevant environmental parameters are essential for real-time EO systems performance assessment. Direct measurement of slant path extinction would be most desirable. This motivated a careful investigation of lidar (light detection and ranging) techniques including improvements to single-ended lidar profile inversion algorithms and development of new lidar techniques such as double-ended and dual-angle configurations. It was concluded that single-ended, single frequency lidars can not be used to infer slant path extinction with an accuracy necessary to make meaningful performance assessments. Other lidar configurations may find limited application in model validation and research efforts. No technique has emerged yet which could be considered ready for shipboard implementation. A shipboard real-time performance assessment system was developed and named PREOS (Performance and Range for EO Systems). PREOS has been incorporated into the Navy's Tactical Environmental Support System (TESS). The present version of PREOS is a first step in accomplishing the complex task of real-time systems performance assessment. Improved target and background models are under development and will be incorporated into TESS when tested and validated. A reliable assessment capability can be used to develop Tactical Decision Aids (TDAs). TDAs permit optimum selection or combination of sensors and estimation of a ship's own vulnerability against hostile systems.

Paper Details

Date Published: 1 September 1990
PDF: 37 pages
Proc. SPIE 1312, Propagation Engineering: Third in a Series, (1 September 1990); doi: 10.1117/12.21894
Show Author Affiliations
Juergen H. Richter, Naval Ocean Systems Ctr. (United States)
Herbert G. Hughes, Naval Ocean Systems Ctr. (United States)

Published in SPIE Proceedings Vol. 1312:
Propagation Engineering: Third in a Series
Luc R. Bissonnette; Walter B. Miller, Editor(s)

© SPIE. Terms of Use
Back to Top