System and method of identifying tagged articles

• US 8,384,545 B2
• Filed: 12/07/2009
• Issued: 02/26/2013
• Est. Priority Date: 12/07/2009
• Status: Active Grant

• Current Assignee: Meps Real-Time, Inc.
• Original Assignee: Meps Real-Time, Inc.
• Inventors: Hussain, Shariq, Shamblin, Jeffrey
• Primary Examiner(s): Mehmood, Jennifer
• Assistant Examiner(s): SHERWIN, RYAN W
• Application Number:
  US12/631,861
• Publication Number:
  US 20110133905A1
• Time in Patent Office: 1,177 Days
• Field of Search: 3405721-5729, 340 101- 106, 340/568.1, 340/570, 340/545.6, 700/231, 700/242, 235/385, 312/209, 312/330.1, 312/334.35
• US Class Current: 340/572.1
• CPC Class Codes: G06K 19/07749 the record carrier being capable of non-contact communication, e.g. constructional details of the antenna of a non-contact smart card
• CPC Class Codes: G06K 7/10168 the powering being adversely affected by environmental influences, e.g. unwanted energy loss in the interrogation signal due to metallic or capacitive objects in the proximity of the interrogation device or in the proximity of the interrogated record carrier
• CPC Class Codes: G06K 7/10178 including auxiliary means for focusing, repeating or boosting the electromagnetic interrogation field comparable booster antennas integrated on the record carrier itself G06K19/07794
• CPC Class Codes: G06K 7/10297 arrangements for handling protocols designed for non-contact record carriers such as RFIDs NFCs, e.g. ISO/IEC 14443 and 18092 cryptographic protocols H04L9/00; network security protocols H04L63/00; real-time communication protocols in data switching networks H04L65/00; network protocols for data switching network services H04L67/00
• CPC Class Codes: G06K 7/10366 the interrogation device being adapted for miscellaneous applications
• CPC Class Codes: G06Q 10/087 Inventory or stock management, e.g. order filling, procurement or balancing against orders
• CPC Class Codes: G06Q 30/00 Commerce
• CPC Class Codes: G06Q 50/22 Social work or social welfare, e.g. community support activities or counselling services
• CPC Class Codes: G16H 10/40 for data related to laboratory analysis, e.g. patient specimen analysis
• CPC Class Codes: G16H 10/60 for patient-specific data, e.g. for electronic patient records
• CPC Class Codes: G16H 10/65 stored on portable record carriers, e.g. on smartcards, RFID tags or CD
• CPC Class Codes: G16H 20/13 delivered from dispensers
• CPC Class Codes: G16H 40/20 for the management or administration of healthcare resources or facilities, e.g. managing hospital staff or surgery rooms
• CPC Class Codes: G16H 40/63 for local operation
• CPC Class Codes: G16H 50/20 for computer-aided diagnosis, e.g. based on medical expert systems
• CPC Class Codes: G16H 70/00 ICT specially adapted for the handling or processing of medical references
• CPC Class Codes: G16H 70/40 relating to drugs, e.g. their side effects or intended usage

Abstract

An automatic data collection system tracks articles by providing a robust electromagnetic (EM) field within an enclosure in which the articles are stored. Respective data carriers, such as RFID tags, attached to each article respond to the electromagnetic field by transmitting unique data identified with each article. Where the frequency of the EM field coupled to the enclosure differs from the natural resonance frequency of the enclosure, the placement of a probe to couple energy to the enclosure is selected to have the reflected phase of the EM energy from walls equal at the probe location thereby producing a robust EM field to activate and/or detect data carriers.

Claims

1. A medical article tracking system for reading a data carrier that is attached to a medical article, the data carrier being responsive to electromagnetic energy (EM) of a frequency f1 in response to which the data carrier provides identification data, the system comprising:

a metallic enclosure having an internal storage area, the metallic enclosure further having electrically conductive walls that completely surround the internal storage area and any medical article with associated data carrier placed therein, the enclosure having a natural frequency of resonance f2 which is different from f1 and to which a data carrier that is responsive to frequency f1 is not responsive;

a probe disposed at a metallic wall of the metallic enclosure within the metallic enclosure, the probe configured to inject electromagnetic energy of a frequency f1 into the metallic enclosure, wherein the position of the probe in relation to the metallic walls of the metallic enclosure is selected so that reflected EM of frequency f1 within the metallic enclosure is in phase at the probe position to thereby optimize power transfer at frequency f1 into the enclosure;

an active impedance matching circuit coupled to the probe and configured to actively more closely match impedance of the probe to impedance of the metallic enclosure at frequency f1;

a storage device located within the internal storage area of the metallic enclosure configured to receive a medical article with an associated data carrier that is responsive to EM at frequency f1; and

a receiving antenna disposed within the metallic enclosure and configured to receive the identification data provided by the data carrier.

2. The medical article tracking system of claim 1 wherein:

the storage device comprises a drawer adapted to move into and out of the metallic enclosure and within which the medical article with associated data carrier is placed;

the metallic enclosure comprises an opening through which the drawer may be moved out of the metallic enclosure so that the medical article may be removed;

the drawer includes a metallic wall that makes contact with the metallic enclosure when the drawer is moved into the metallic enclosure to complete the metallic enclosure so that it completely encloses the medical article when it is in the drawer within the metallic enclosure.

3. The medical article tracking system of claim 2 wherein the drawer is formed of non-electrically conductive material except for a portion of the drawer that forms a portion of the metallic enclosure.

4. The medical article tracking system of claim 1 wherein the metallic enclosure comprises an openable wall portion through which a medical article with associated data carrier that is resident in the storage device may be removed, the openable wall portion being electrically conductive and when placed in a closed position, that contacts the remainder of the metallic enclosure to provide a metallic enclosure that completely surrounds the storage device.

5. The medical article tracking system of claim 1 wherein the receiving antenna is located on an opposite side of the storage device from the probe.

6. The medical article tracking system of claim 1 further comprising a plurality of probes, each probe being mounted at a wall of the metallic enclosure, each of the probes configured to inject (EM) into the enclosure at frequency f1 at its respective position, wherein the position of each probe in relation to the walls of the metallic enclosure is selected to optimize power transfer at frequency f1 into the metallic enclosure to provide coverage of a portion of the metallic enclosure with an electromagnetic field, the position of the probes further selected such that the probes may be sequentially activated to inject their respective EM at frequency f1 into the metallic enclosure to provide a composite EM field.

7. The medical article tracking system of claim 1 wherein the receiving antenna is located outside the storage device.

8. The medical article tracking system of claim 7 wherein the receiving antenna comprises a microstrip patch antenna.

9. The medical article tracking system of claim 1 wherein the active impedance matching circuit is configured to more closely match the impedance of the probe to impedance of the metallic enclosure at frequency f1 as the contents of the storage device change.

10. The medical article tracking system of claim 1 wherein the probe is configured and positioned in the metallic enclosure for operation in the TE01 mode.

11. The medical article tracking system of claim 1 wherein the probe is configured and positioned in the metallic enclosure for operation in the TM01 mode.

12. The medical article tracking system of claim 1 wherein the probe is configured in a shape that results in capacitive coupling.

13. The medical article tracking system of claim 1 further comprising an electromagnetically inert cover placed over the probe configured to protect the probe from damage, wherein the storage device is shaped so that the inert cover extends into the storage device without interference with operation of the storage device.

14. A system for tracking a medical article having a data carrier attached thereto, the data carrier being responsive to electromagnetic energy (EM) of a frequency f1 in response to which the data carrier broadcasts identification data, the system comprising:

a metallic enclosure having an internal storage area, the metallic enclosure further having electrically conductive walls that completely surround the internal storage area and any medical article with associated data carrier placed therein, the enclosure having a natural frequency of resonance of f2, wherein f2 is different from f1 and to which data carriers responsive to frequency f1 are not responsive;

a probe disposed at a metallic wall of the metallic enclosure within the metallic enclosure, the probe configured in a shape to capacitively couple with the metallic enclosure to inject electromagnetic energy of a frequency fl into the metallic enclosure, wherein the position of the probe in relation to the metallic walls of the metallic enclosure is selected so that reflected EM of frequency f1 within the metallic enclosure is in phase at the probe position to thereby optimize power transfer at frequency f1 into the enclosure;

a drawer movably disposed within the internal storage area of the metallic enclosure, the drawer configured to store medical articles having respective data carriers that are responsive to frequency fl;

an active impedance matching circuit coupled to the probe and configured to actively more closely match impedance of the probe to impedance of the metallic enclosure at frequency f1 as contents of the drawer change;

a receiving antenna disposed within the metallic enclosure outside the drawer and configured to receive the identification data provided by data carriers.

15. The medical article tracking system of claim 14 wherein the receiving antenna comprises a microstrip patch antenna.

16. The medical article tracking system of claim 14 wherein the probe is configured and positioned in the metallic enclosure for operation in the TE01 mode.

17. The medical article tracking system of claim 14 wherein the probe is configured and positioned in the metallic enclosure for operation in the TM01 mode.

18. The medical article tracking system of claim 14 further comprising an electromagnetically inert cover placed over the probe configured to protect the probe from damage, wherein the drawer is shaped so that the inert cover extends into the drawer without interference with movement of the drawer into and out of the metallic enclosure.