Automatic mode detection in a dual operating mode RFID tag

• US 8,618,916 B2
• Filed: 05/10/2012
• Issued: 12/31/2013
• Est. Priority Date: 05/31/2005
• Status: Active Grant

• Current Assignee: Amtech Systems LLC (Roper Technologies, Inc.)
• Original Assignee: Amtech Systems LLC (Roper Technologies, Inc.)
• Inventors: Gravelle, Kelly, Tiernay, Robert W., Scott, Dale L., Johnson, Charles A., Weytjens, Filip, Burnett, Matthew K.
• Primary Examiner(s): SYED, NABIL H
• Application Number:
  US13/468,371
• Publication Number:
  US 20120306627A1
• Time in Patent Office: 600 Days
• Field of Search: 340/10.1, 340/10.2, 340/10.3, 340/10.31, 340/10.32, 340/10.33, 340/10.34, 340/10.4, 340/10.41, 340/10.42, 340/10.5, 340/10.51, 340/10.52, 340/572.1, 340/572.7, 455/11.1, 235/383, 235/451
• US Class Current: 340/10.51
• CPC Class Codes: G06K 19/0707 the arrangement being capable of collecting energy from external energy sources, e.g. thermocouples, vibration, electromagnetic radiation G06K19/0702 takes precedence
• CPC Class Codes: G06K 19/0712 the arrangement being capable of triggering distinct operating modes or functions dependent on the strength of an energy or interrogation field in the proximity of the record carrier active means for hindering electromagnetic reading or writing G06K19/07336
• 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 7/10198 setting parameters for the interrogator, e.g. programming parameters and operating modes
• CPC Class Codes: H04Q 5/22 the subordinate centre not permitting interconnection of subscribers connected thereto

Abstract

A multi-mode, preferably dual mode, radio frequency identification (RFID) tag is adapted for automatic detection of whether a RFID reader located within communication range of the RFID tag is transmitting a continuous wave (CW) or modulated wave types of RF signal, and accordingly, mandating a response from the tag in read-only (RO) mode or read/write (R/W) mode, respectively. The tag includes means for designating one of the RO and R/W operating modes as a default mode of the tag, and for switching the tag from its default mode to its other operating mode, and vice versa, according to a rule for determining the frequency of occurrence of a selected event related to signal type of the reader. A device-implemented method of this automatic detection, and a method of fabricating the tag, are also disclosed.

Claims

1. A method for an RFID interrogator to communicate with an RFID transponder that responds to one of a first or second interrogator communication protocol as a dominant protocol and the other of said interrogator communication protocols as a recessive protocol, wherein said first interrogator communication protocol is a read only protocol consisting of a read mode and wherein said second interrogator communication protocol is a read/write protocol consisting of a read mode and a write mode, said method comprising:

transmitting by said interrogator an interrogation signal according to the first or second interrogation communication protocol, wherein

said first interrogation signal is detected by the transponder;

if the transponder detects said recessive protocol, said transponder switches automatically to said recessive protocol according to a reluctance rule based on the dominant protocol of the transponder and a first set of signal characteristics associated with said interrogation signal detected by the transponder;

and wherein if the transponder detects said dominant protocol, said transponder reverts automatically to the dominant protocol according to an acceptance rule based on the dominant protocol of the transponder and on a second set of signal characteristics associated with the interrogation signal detected by the transponder;

wherein a first set of reluctance and acceptance rules for the first interrogator communication protocol and a second set of reluctance and acceptance rules for the second interrogator communication protocol are programmed into the transponder'"'"'s hardware, the transponder responding according to said first set of reluctance and acceptance rules based on a programmed bit designating the first interrogator communication protocol as the dominant protocol or the transponder responding according to said second set of reluctance and acceptance rules based on said programmed bit designating the second interrogator communication protocol as the dominant protocol.

2. A system for RFID communications comprising an interrogator and a transponder that responds to one of a first or second interogator communication protocol as a dominant protocol and the other of said interrogator communication protocols as a recessive protocol, wherein said first interrogator communication protocol is a read only protocol consisting of a read mode and wherein said second interrogator communication protocol is a read/write protocol consisting of a read mode and a write mode, said system comprising:

an interrogator programmed to transmit an interrogation signal according to the first or second interrogation communication protocol, and

a transponder having circuitry to detect said transmission interrogation signal;

the transponder further having circuitry arranged so that if the transponder detects said recessive protocol, said transponder switches automatically to said recessive protocol according to a reluctance rule based on the dominant protocol of the transponder and a first set of signal characteristics associated with said interrogation signal detected by the transponder;

and wherein if the transponder detects said dominant protocol, said transponder reverts automatically to the dominant protocol according to an acceptance rule based on the dominant protocol of the transponder and on a second set of signal characteristics associated with the interrogation signal detected by the transponder;

wherein a first set of reluctance and acceptance rules for the first interrogator communication protocol and a second set of reluctance and acceptance rules for the second interrogator communication protocol are programmed into the transponder'"'"'s hardware, the transponder responding according to said first set of reluctance and acceptance rules based on a programmed bit designating the first interrogator communication protocol as the dominant protocol or the transponder responding according to said second set of reluctance and acceptance rules based on said programmed bit designating the second interrogator communication protocol as the dominant protocol.