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AssigneeThe United States of America as represented by the Secretary of the Navy
InventorsJohn J. Holmes, John F. Scarzello, Bruce R. Hood
Estimating the term…
Gradiometers are encompassingly disposed, relative to an object of interest, in a configuration generally describing a closed prolate spheroidal shape, and the measurements taken by the gradiometers are mathematically processed. The gradiometric measurements are defined as directional derivatives which exist in equations involving directional derivatives and prolate spheroidal multipole moments of said entity. The prolate spheroidal multipole moments are thereby calculated, and these prolate spheroidal multipole moment values are extrapolated to ascertain the magnetic fields (equivalently expressed, the magnetic signatures) associated with the object and inwardly delimited by the prolate spheroid. The practitioner can optimize such distribution numerically, orientationally and/or positionally by using the equations involving directional derivatives and prolate spheroidal multipole moments. Extraneous magnetic field effects (e.g., applied fields, earth fields) are inherently excluded, thus obviating the object's removal from an electromagnetic test facility.
A method for determining at least one magnetic field signature of an entity, said method comprising performing gradiometric measurements and processing said gradiometric measurements, wherein said performing of said gradiometric measurements includes using plural gradiometers which are arranged so as to generally describe a closed three-dimensional geometric shape which surrounds said entity, and wherein said processing of said gradiometric measurements includes, based on said gradiometric measurements, determining the multipole moments of said entity, said multipole moments corresponding to said closed three-dimensional geometric shape.
A computer program product comprising a computer useable medium having computer program logic recorded thereon for enabling a computer to determine at least one magnetic field signature of an entity, said computer program logic comprising means for enabling said computer to determine the prolate spheroidal multipole moments of said entity, wherein said prolate spheroidal multipole moments are based on gradiometric measurements performed using plural gradiometers which are arranged so as to generally describe a prolate spheroidal shape which surrounds said entity.
Apparatus for determining at least one magnetic field signature of an entity, said apparatus comprising:
Dependencies are inferred from the claim text.