×

Tracking systems, passive RFIDs, methods of locating and identifying RFIDs, and methods of tracking items

  • US 7,855,643 B2
  • Filed: 11/10/2006
  • Issued: 12/21/2010
  • Est. Priority Date: 11/10/2006
  • Status: Expired due to Fees
First Claim
Patent Images

1. A tracking system, comprising:

  • a plurality of interrogators;

    a plurality of RFIDs, said plurality of RFIDs including a first subset of the RFIDs and a second subset of the RFIDS;

    a first of said plurality of interrogators and said first subset of RFIDs configured for selective interrogation of the first subset of the RFIDs, said first subset of the RFIDs being configured to change a first observable property responsive to interrogation; and

    a second of said plurality of interrogators and said second subset of RFIDs configured for selective interrogation of the second subset of the RFIDs, said second subset of the RFIDs being configured to change a second observable property responsive to interrogation, wherein at least one RFID is configured to display shipping information responsive to interrogation by an interrogator.

View all claims
  • 4 Assignments
Timeline View
Assignment View
    ×
    ×