Communications: electrical – Condition responsive indicating system – Specific condition
Reexamination Certificate
2006-10-10
2006-10-10
Lee, Benjamin C. (Department: 2612)
Communications: electrical
Condition responsive indicating system
Specific condition
C340S528000, C340S539100, C340S571000, C340S572700
Reexamination Certificate
active
07119692
ABSTRACT:
Techniques for detecting radio-frequency identification (RFID) tags are disclosed. For example, an exit control system is described that detects unauthorized removal of articles from a protected facility. A series of antennas are setup to produce interrogation corridors located near the exit of the protected area. RFID tags are attached to the articles to be protected. Each tag includes information that uniquely identifies the article to which it is affixed and status information as to whether the articles removal from the facility is authorized. The RF reader outputs RF signals through the antennas to create electromagnetic fields within the interrogation corridors. The reader outputs RF power from a single port to the multiple antennas via a splitter/combiner. In this way, a single RF reader with only one transmitter/receiver port simultaneously interrogates multiple antennas. A variety of techniques are described by which the reader can detect the removal of an unauthorized article.
REFERENCES:
patent: 4281321 (1981-07-01), Narlow et al.
patent: 4635041 (1987-01-01), Maimann et al.
patent: 4739328 (1988-04-01), Koelle et al.
patent: 4864158 (1989-09-01), Koelle et al.
patent: 4870391 (1989-09-01), Cooper
patent: 4888591 (1989-12-01), Landt et al.
patent: 5030941 (1991-07-01), Lizzi et al.
patent: 5055659 (1991-10-01), Hendrick et al.
patent: 5103234 (1992-04-01), Watkins et al.
patent: 5126749 (1992-06-01), Kaltner
patent: 5353011 (1994-10-01), Wheeler et al.
patent: 5387900 (1995-02-01), Plonsky et al.
patent: 5926093 (1999-07-01), Bowers et al.
patent: 6020856 (2000-02-01), Alicot
patent: 6037879 (2000-03-01), Tuttle
patent: 6069564 (2000-05-01), Hatano et al.
patent: 6094173 (2000-07-01), Nylander
patent: 6104333 (2000-08-01), Wood, Jr.
patent: 6335686 (2002-01-01), Goff et al.
patent: 6396341 (2002-05-01), Pehlke
patent: 6487395 (2002-11-01), Durec et al.
patent: 2004/0164864 (2004-08-01), Chung et al.
patent: 2004/0201456 (2004-10-01), Cole
patent: 0 435 198 (1991-07-01), None
patent: 0 608 039 (1994-07-01), None
patent: 06076185 (1994-03-01), None
patent: WO 02/33511 (2002-04-01), None
patent: WO 03/040950 (2003-05-01), None
“Algorithm For RFID Security”, filed Nov. 10, 2003, U.S. Appl. No. 10/705,733.
Goff Edward D.
Jesme Ronald D.
Lieffort Seth A.
Mercer Thomas C.
3M Innovative Properties Company
Buss Melissa E.
Lee Benjamin C.
Tang Son
LandOfFree
System for detecting radio-frequency identification tags does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with System for detecting radio-frequency identification tags, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and System for detecting radio-frequency identification tags will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3633721