RFID TAG READING APPARATUS AND METHOD

• US 20100156604A1
• Filed: 12/22/2008
• Published: 06/24/2010
• Est. Priority Date: 12/22/2008
• Status: Abandoned Application

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Dong, Yanshi
• Application Number:
  US12/340,786
• Publication Number:
  US 20100156604A1
• Time in Patent Office: Days
• US Class Current: 340/10.300
• CPC Class Codes: H04Q 2209/47 using RFID associated with sensors
• CPC Class Codes: H04Q 2209/753 where the polling of the sub-stations is synchronous
• CPC Class Codes: H04Q 9/00 Arrangements in telecontrol or telemetry systems for selectively calling a substation from a main station, in which substation desired apparatus is selected for applying a control signal thereto or for obtaining measured values therefrom

Abstract

A method comprises identifying a known-ID-number set comprising at least two ID numbers of corresponding tags and each ID number comprises a plurality of bit positions; calculating an entropy between each corresponding bit position in the known-ID-number set; identifying the bit position having a greatest entropy; and transmitting a reading query to the tags in a communication range. The reading query includes a differential specific number corresponding to the bit position having the greatest entropy.

Claims

1. A method comprising:

identifying a known-ID-number set comprising at least two ID numbers of corresponding tags, where each ID number comprises a plurality of bit positions;

calculating an entropy between each corresponding bit position in the known-ID-number set;

identifying the bit position having a greatest entropy; and

transmitting a reading query to the tags in a communication range, the reading query including a differential specific number corresponding to the bit position having the greatest entropy.

2. The method according to claim 1, wherein transmitting a reading query to the tags in a communication range comprises transmitting the reading query with either “

0”

or “

1”

corresponding to the bit position having the greatest entropy.

3. The method according to claim 2, wherein transmitting a reading query to the tags in a communication range comprises transmitting a first reading query with “

0”

at the bit position having the greatest entropy and masks in other bit positions, and a second reading query with “

1”

at the bit position having the greatest entropy and masks in other bit positions, a mask representing either “

0”

or “

1”

.

4. The method according to claim 1 further comprising identifying a bit position having a second greatest entropy, and transmitting a reading query to the tags in a communication range, the reading query including a differential specific number corresponding to the bit position having the second greatest entropy.

5. The method according to claim 4 further comprising sending a reading query including a differential specific number corresponding to the a bit position having a second greatest entropy when no ID number is identified.

6. The method according to claim 1 further comprising adding ID numbers identified to the known-ID-number set to get an updated known-ID-number set, and calculating an updated entropy between each corresponding bit position in the updated known-ID-number set.

7. The method according to claim 1, wherein said at least two ID numbers are prior knowledge of the tags.

8. The method according to claim 1, wherein the step of identifying at least two IDs of two corresponding tags being conducted by any possible identification method.

9. An apparatus comprising:

a memory to store identification numbers of tags; and

a processor for;

identifying a known-ID-number set comprising at least two ID numbers of corresponding tags;

calculating an entropy between each corresponding bit position of the at least two ID numbers in the known-ID-number set;

identifying the bit position having a greatest entropy; and

transmitting a reading query to the tags in a communication range, the reading query including a differential specific number corresponding to the bit position having the greatest entropy.

10. The apparatus according to claim 9, wherein the processor is configured to transmit the reading query with either “

0”

or “

1”

corresponding to the bit position having the greatest entropy.

11. The apparatus according to claim 10, wherein the processor is configured to transmit a first reading query with “

0”

at the bit position having the greatest entropy and bit masks in other bit positions, and to transmit a second reading query with “

1”

at the bit position having the greatest entropy and bit masks in other bit positions, wherein a bit mask representing either “

0”

or “

1”

.

12. The apparatus according to claim 9, wherein the processor is further configured to identify a bit position having a second greatest entropy, and transmit a reading query to the tags in a communication range, the reading query including a differential specific number corresponding to the bit position having the second greatest entropy.

13. The apparatus according to claim 12, wherein the processor is further configured to send a reading query including a differential specific number corresponding to the a bit position having a second greatest entropy when no ID number is identified.

14. The apparatus according to claim 9, wherein the processor is further configured to add ID numbers identified to the known-ID-number set to obtain an updated known-ID-number set, and calculate an updated entropy between each corresponding bit position in the updated known-ID-number set.

15. A storage medium comprising a plurality of instructions, which when executed, cause an interrogator to:

identify a known-ID-number set comprising at least two ID numbers of corresponding tags;

calculate an entropy between each corresponding bit position in the known-ID-number set;

identify the bit position having a greatest entropy; and

transmit a reading query to the tags in a communication range, the reading query including a differential specific number corresponding to the bit position having the greatest entropy.