Apparatus and method for locating containers and contents of containers using radio frequency tags

• US 6,335,685 B1
• Filed: 03/09/2000
• Issued: 01/01/2002
• Est. Priority Date: 03/09/2000
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Schrott, Alejandro Gabriel, von Gutfeld, Robert Jacob
• Primary Examiner(s): Lee, Benjamin C.
• Assistant Examiner(s): PHAM, TOAN NGOC
• Application Number:
  US09/521,712
• Time in Patent Office: 663 Days
• Field of Search: 340/572.1, 340/572.4, 340/572.7, 340/572.8, 340/825.36, 340/10.1, 340/10.3, 340/10.32, 340/10.33, 340/10.42, 340/10.51, 340/825.49, 340/5.92, 235/375, 235/385
• US Class Current: 340/572.1
• CPC Class Codes: G06K 17/00 Methods or arrangements for effecting co-operative working between equipments covered by two or more of main groups G06K1/00 - G06K15/00, e.g. automatic card files incorporating conveying and reading operations
• CPC Class Codes: G06K 19/0704 the battery being rechargeable, e.g. solar batteries
• CPC Class Codes: G06K 19/0723 the record carrier comprising an arrangement for non-contact communication, e.g. wireless communication circuits on transponder cards, non-contact smart cards or RFIDs
• CPC Class Codes: G06K 7/10079 the collision being resolved in the spatial domain, e.g. temporary shields for blindfolding the interrogator in specific directions

Abstract

A computerized base station system communicates with radio frequency tags attached to one or more objects. Included in the system is a separate position detector that determines the position of one or more of the tags within a time increment and within a field of the base station. A communication process reads information from one or more of the tags within the time increment and associates the position determined with the information of the respective tag.

Claims

1. A base station system for communicating with radio frequency tags attached to one or more objects, the objects each having a position, the base station further comprising:

one or more computers, each having one or more central processing units (CPUs) and one or more memories;

a position detector for determining the position of one or more of the tags within a time increment; and

a communication process, executed by one or more of the CPUs, that reads information from one or more of the tags within the time increment and associates the position determined with the information of the respective tag in one or more of the memories, wherein the position is determined at least in part as a function of time within the time increment.

2. A system, as in claim 1, where the position detector has a first location device and a second location device and the position is determined as being between the first and second location devices.

3. A system, as in claim 2, where the first and second location devices are any one or more of the following:

an electric sensor, an acoustic sensor, a photocell, and a pressure sensor.

4. A system, as in claim 1, where the position detector is comprised of a directional beam antenna.

5. A system, as in claim 4, where the directional beam antenna scans in the horizontal and vertical directions to determine the position.

6. A system, as in claim 4, where the directional beam antenna scans only in the vertical direction to determine the position.

7. A system, as in claim 6, where the object attached to the tag is moving in a horizontal direction with respect to the system.

8. A system, as in claim 1, where the position detector is comprised of a light source.

9. A system, as in claim 8, where the light source is any one or more of the following:

a laser and a focused lamp.

10. A system, as in claim 8, where the light source is comprised of a laser that activates the tags from which the information is read.

11. A system, as in claim 10, where the laser activates the tag using any one or more of the following:

a light sensitive switch and a photo cell.

12. A system, as in claim 1, where the object is comprised of any one or more of the following:

a container, a storage area, a pallet, a box, and a shipping container.

13. A method for communicating with radio frequency tags attached to one or more objects, the objects each having a position, the method comprising the steps of:

using a position detector to determine the position of one or more of the tags within a time increment;

reading information from one or more of the tags within the time increment; and

associating the position with the information of the respective tag, wherein the position is determined at least in part as a function of time within the time increment.

14. A system for communicating with radio frequency tags attached to one or more objects, the objects each having a position, the system comprising:

means for using a position detector to determine the position of one or more of the tags within a time increment;

means for reading information from one or more of the tags within the time increment; and

means for associating the position with the information of the respective tag, wherein the position is determined at least in part as a function of time within the time increment.

15. A computer program, executed by a computer, that performs the steps of:

receiving the position of one or more of the tags within a time increment from a position detector;

reading information from one or more radio frequency tags within the time increment; and

associating the position with the information of the respective tag, wherein the position is determined at least in part as a function of time within the time increment.

16. A method for communicating with individual ones of a plurality of radio frequency tags attached to individual ones of a plurality of objects, the method comprising:

sequentially interrogating individual ones of the radio frequency tags with a tag reader, where sequentially interrogating comprises causing relative motion between the radio frequency tags and the tag reader;

receiving information sequentially from individual ones of the radio frequency tags in response to being interrogated; and

associating a position of individual ones of the objects in space with the received information.

17. A method as in claim 16, where the relative motion results from scanning a beam over the objects.

18. A method as in claim 16, where the relative motion results from scanning a beam over the objects along two axes.

19. A method as in claim 16, where the relative motion results from scanning a beam over the objects along one axis, and translating the plurality of objects along a second axis.

20. A method as in claim 16, where the relative motion results from scanning one of a radio frequency beam or a light beam over the objects.