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(11)

EP 0 876 583 A1

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(43) Date of publication: 11.11.1998 Bulletin 1998/46 (21) Application number: 97903061.0 (22) Date of filing: 22.01.1997

(51) International Patent Classification (IPC):  G01B 11/ 00( . ) G01J 1/ 06( . ) G01S 5/ 16( . ) G01S 17/ 42( . ) G01S 17/ 66( . ) G01J 1/ 04( . ) G01J 1/ 42( . ) G01S 7/ 481( . ) G01J 5/ 08( . ) (86) International application number: PCT/US1997/001011 (87) International publication number: WO 1997/027449 (31.07.1997 Gazette 1997/33)

(84) Designated Contracting States: AT BE CH DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE (30) Priority: 23.01.1996 US 19960589104 23.01.1996 US 19960589105 23.01.1996 US 19960590290 10.01.1997 US 19970781826 (71) Applicant: SCIENCE APPLICATIONS INTERNATIONAL CORPORATION San Diego California 92121 (US)

(72) Inventors: RAMER, David, P. Dayton, OH 45410 (US) WATSON, Harold, E. Kettering, OH 45429-1858 (US) RITTER, Michael, P. Dayton, OH 45431 (US) EPLING, Bobby, L. Bellbrook, OH 45305 (US) SCHMITT, Mark, G. Huber Heights, OH 45424-3135 (US) RAINS, Jack, C., Jr. Herndon, VA 22071 (US) (74) Representative: Read, Matthew Charles, et al  Venner Shipley & Co. 20 Little Britain London EC1A 7DH London EC1A 7DH (GB)