Wireless locating and tracking systems
AssigneeSymbol Technologies, Inc.
InventorRaj Bridgelall
Life of this patent
Estimating the term…
Abstract
A locating and tracking system is provided in which the assets desired to be located and tracked are associated with either radio frequency (RF) tags or radio frequency identification and radio frequency data communication (RFID/RFDC) devices. Depending on which device is attached to the asset, the other device is located at known locations. The RFID/RFDC devices interrogate and receive signals from the RF tags. The received information is sent to a host computer. With the location of either the RF tags or RFID/RFDC devices known, the assets may be located and tracked. An improved RF tag antenna design is also provided by using a switching mechanism connected to at least two antennas.
Claims16
A method for tracking an asset with a radio frequency identification/radio frequency data communication (RFID/RFDC) device and a plurality of marker tags, comprising:
- sending an interrogation signal from the RFID/RFDC device that has an interrogation range;
- receiving a first response signal to the interrogation signal from a first marker tag located at a first known location within the interrogation range;
- processing the first response signal with the RFID/RFDC device to determine a first identity of the first marker tag;
- receiving a second response signal to the interrogation signal from a second marker tag located at a second known location within the interrogation range;
- processing the second response signal with the RFID/RFDC device to determine a second identity of the second marker tag;
- and
- processing the first identity of the first marker tag and the second identity of the second marker to track the asset.
A system for tracking an asset with a plurality of marker tags located at known locations, comprising:
- a radio frequency identification/radio frequency data communication (RFID/RFDC) device associated with the asset wherein the RFID/RFDC device:
- sends an interrogation signal that has an interrogation range;
- receives a first response signal to the interrogation signal from a first marker tag located at a first known location within the interrogation range;
- processes the first response signal to identify a first identity of the first marker tag;
- receives a second response signal to the interrogation signal from a second marker tag located at a second known location within the interrogation range;
- processes the second response signal to identify a second identity of the second marker tag;
- and
- a host computer system that receives the first identity of the first marker tag and the second identity of the second marker tag from the RFID/RFDC device and determines the location of the RFID/RFDC device from the first identity of the first marker tag and the second identity of the second marker tag.
Dependencies are inferred from the claim text.