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SWATH SUBBOTTOM SYSTEM 



NRL is presently developing a unique Swath Subbottom System (SSS). 

 The SSS will have a capability to provide low- and high-frequency (LF 

 from 500 to 2000Hz and HF at 11.5kHz) backscatter from the seafloor 

 interface and the upper 50-100 meters of the seafloor sediments. This 

 system is unique in that the parametric techniques used produce 

 equivalent beamwidths at both HF and LF, and provides simultanaous 

 information on bottom morphology and subbottom heterogeneities. 



Because of its swath mapping capabilities, the SSS is useful not only 

 for Navy ASW and navigation applications, but also offers significant 

 potential for providing subbottom "maps" of offshore areas of interest to 

 the petroleum industry, and for mapping and exploitation of the EEZ. 



AIRCRAFT BASED REMOTE SENSING 



HYPERSPECTRAL CHARACTERIZATION 



ONR and NRL are developing algorithms, tools and methodology to 

 extract coastal optical parameters and variability of bottom properties 

 (spectral reflectivities, bottom types and mixtures) using very high 

 spectral resolution (hyperspectral) passive remote sensing optical data. 

 This data is useful in amphibious warfare (AMW), surveillance and other 

 operations. The major optical properties are divided into (1) water 

 properties (attenuation coefficient, chlorophyll concentrations, suspended 

 sediments) and (2) bottom properties (spectral reflectivities, bottom 

 types and mixtures). The Navy emphasis is on the bottom properties. Such 

 optical parameters are needed to assess MCM sensor effectiveness during 

 mine clearance/avoidance operations in coastal areas. 



Presently techniques are being developed to exploit satellite and 

 aircraft multispectral digital imagery for naval applications. In 

 particular, specialized image-processing computer algorithms to extract 

 water depth information from multispectral imagery have been developed. 

 Other image processing procedures and techniques of image enhancements, 

 warping to standard map projections, and land classification have also 

 been investigated. A number of specialized statistical techniques have 

 also been developed to enhance the imagery to allow the detection and 

 location of small, shallow objects (hazards to navigation). 



