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This paper presents feasibility studies of a multispectral moving target detection (MTD) system designed to detect and track low-signature moving targets. The system performs multispectral detection based on linear and nonlinear maximum discrimination and representation features (MRDF) for low-signature target detection and correlation tracking of slowly moving targets in clutter. Multispectral detection was tested against multispectral data from an acousto-optic tunable filter (AOTF) in the visible and near infrared. The feasibility of correlation target tracking was demonstrated with actual Army MICOM FLIR long wavelength infrared (LWIR: 8 to 12 rim) images ofmoving vehicles and tanks in clutter.

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This work reports a theoretical study of x-ray scattering from simple liquids when environmental effects are included. An instantaneous configuration-dependent scattering factor is defined for a molecule in a liquid. Using statistical mechanics and physical principles, an expression is derived that corrects the usual scattering equations for both coherent and incoherent radiation. Using the new results, scattering data from several states of liquid helium and liquid argon are analyzed. Comparison of correlated scattering factors and isolated molecule scattering factors indicate that corrections are significant only in the vicinity of the hard core radius and for values of the wave vector s≳0.5 Å−1. Incorporating correlation effects into scattering data for these liquids, the resultant radial distribution function peak is depressed an average of 1% and computed potential well depths lowered by an average of 5%. Although treatment of data in this manner leads to better coincidence with theoretical predictions, the accuracy with which data for simple liquids may be obtained at the present time may not warrant a complete treatment as presented here. However, indications are that in polar and oriented liquids it is unjustified to leave out environmental effects when an accurate treatment is desired.

The analysis of the performance of a binary optical element requires a physical optics calculation because of the diffractive nature of such elements. We have developed a number of software tools for this analysis, which are based on the Kirchhoff-Fresnel diffraction integral. These tools allow investigation of results of diffraction both in and out of the focal plane. The programs take a given (nonbinary) element, convert it to a binary element with prescribed etching resolutions and etching depths, and perform the diffractive calculation. The diffraction is calculated by a number of means (direct numerical integration, Fresnel approximation, evaluation of analytic formulas). The software also computes quantitative measures of performance, such as blur spot sizes, diffraction efficiencies, and wavelength separation (for dispersive elements). We discuss the abilities and limitations of the codes and present sample calculations.