Classical scattering theory of waves from the view point of an eigenvalue problem and application to target identification
- Oak Ridge National Lab., TN (United States)
- Naval Research Lab. Detachment, Stennis Space Center, MS (United States)
The Helmholtz-Poincare Wave Equation (H-PWE) arises in many areas of classical wave scattering theory. In particular it can be found for the cases of acoustical scattering from submerged bounded objects and electromagnetic scattering from objects. The extended boundary integral equations (EBIE) method is derived from considering both the exterior and interior solutions of the H-PWE`s. This coupled set of expressions has the advantage of not only offering a prescription for obtaining a solution for the exterior scattering problem, but it also obviates the problem of irregular values corresponding to fictitious interior eigenvalues. Once the coupled equations are derived, they can by obtained in matrix form be expanding all relevant terms in partial wave expansions, including a biorthogonal expansion of the Green function. However some freedom of choice in the choice of the surface expansion is available since the unknown surface quantities may be expanded in a variety of ways to long as closure is obtained. Out of many possible choices, we develop an optimal method to obtain such expansions which is based on the optimum eigenfunctions related to the surface of the object. In effect, we convert part of the problem (that associated with the Fredholms integral equation of the first kind) an eigenvalue problem of a related Hermition operator. The methodology will be explained in detail and examples will be presented.
- Research Organization:
- Oak Ridge National Lab., TN (United States)
- Sponsoring Organization:
- USDOE, Washington, DC (United States); Department of Defense, Washington, DC (United States)
- DOE Contract Number:
- AC05-84OR21400
- OSTI ID:
- 10190185
- Report Number(s):
- CONF-930445-26; ON: DE94000472; TRN: 93:025420
- Resource Relation:
- Conference: Society of Photo-Optical Instrumentation Engineers (SPIE) OE/aerospace science and sensing meeting,Orlando, FL (United States),11-16 Apr 1993; Other Information: PBD: [1993]
- Country of Publication:
- United States
- Language:
- English
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