System for spatially adjustable excitation of leadless miniature marker

Patent 6822570 Issued on November 23, 2004. Estimated Expiration Date:

August 7, 2022. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

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Inventors

Assignee

Calypso Medical Technologies, Inc.

Application

No. 10213980 filed on 08/07/2002

US Classes:

340/572.1, Detectable device on protected article (e.g., "tag")340/572.7, Specified antenna structure343/742Plural

Examiners

Primary: Mullen, Thomas

Attorney, Agent or Firm

Perkins Coie LLP

Foreign Patent References

0 719 420 EP 11/01/1999
1 034 738 EP 09/01/2000
WO 9533519 WO 12/01/1995
WO 9608208 WO 03/01/1996
WO 9608999 WO 03/01/1996
WO 9736192 WO 10/01/1997
WO 9748438 WO 12/01/1997
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WO 8808282 WO 11/01/1998
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WO 9927839 WO 06/01/1999
WO 9930182 WO 06/01/1999
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WO 0024332 WO 05/01/2000
WO 0051514 WO 09/01/2000
WO 0134049 WO 05/01/2001
WO 0154765 WO 08/01/2001
WO 0219908 WO 03/01/2002
WO 02100485 WO 12/01/2002

International Class

G08B 1314

Abstract

A system for generating a magnetic field for excitation of a leadless marker assembly. The system of at least one embodiment includes a source generator that generates a plurality of alternating electrical signals each having an independently adjustable phase. A plurality of excitation coils are configured to simultaneously receive a respective one of the alternating electrical signals at a selected phase to generate a magnetic field. The phase of the alternating electrical signal for each excitation coil is independently adjustable relative to the phase of the alternating electrical signal for the other excitation coils so as to adjust the magnetic field from the respective coil. The magnetic fields from the excitation coils combine to form a spatially adjustable excitation field for excitation of the remote leadless marker assembly.

Other References

International Search Report dated Jan. 24, 2003, PCT Application No. PCT/US/29390.
Hsiao, K., “Fast Multi-Axis Tracking of Magnetically-Resonant Passive Tags: Methods and Applications,” Feb. 2001, Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science.