Tag identification systems and methods

• US 9,870,660 B1
• Filed: 01/27/2014
• Issued: 01/16/2018
• Est. Priority Date: 01/27/2014
• Status: Active Grant

• Current Assignee: Synapse Wireless Incorporated (Mcwane Incorporated)
• Original Assignee: Synapse Wireless Incorporated (Mcwane Incorporated)
• Inventors: Patterson, Wade C.
• Primary Examiner(s): Backer, Firmin
• Assistant Examiner(s): Aziz, Adnan
• Application Number:
  US14/165,119
• Time in Patent Office: 1,450 Days
• Field of Search: 340 1034, 340 1041
• CPC Class Codes: G06K 19/07 with integrated circuit chips
• CPC Class Codes: G06K 19/0701 at least one of the integrated circuit chips comprising an arrangement for power management
• 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 7/0008 General problems related to the reading of electronic memory record carriers, independent of its reading method, e.g. power transfer
• CPC Class Codes: G06K 7/10009 sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves
• 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: G07C 9/28 the pass enabling tracking or indicating presence

Abstract

In a tag identification system, active tags are configured to emulate at least one passive tag so that existing passive identifications systems, such as passive radio-frequency (RFID) systems or near field communication (NFC) systems, can be retrofitted to operate with the active tag without having to make expensive hardware updates to the readers within the system. The active tag permits continuous monitoring of its movement or status, as may be desired, regardless of its proximity relative to the readers thereby allowing a system to capture more data regarding the tag'"'"'s location and use. In addition, the active tag may be compatible with different passive identification systems thereby permitting it to operate with disparate passive identification systems and obviating the need of the user to carry multiple passive tags.

Claims

1. An active tag for emulating passive tags when communicating with readers of a passive-tag identification system, the readers configured to wirelessly transmit interrogation signals for interrogating passive tags within the passive-tag identification system, the passive tags configured to wirelessly transmit tag signals in response to the interrogation signals, the tag signals including tag identifiers for identifying the passive tags, the active tag comprising:

a communication module for communicating with the readers, the communication module configured to receive at least one interrogation signal from a reader of the passive-tag identification system;

a power supply for powering components of the active tag; and

logic configured to identify the reader based on the received at least one interrogation signal, the logic configured to wirelessly transmit a tag signal via the communication module in response to the received at least one interrogation signal, the logic configured to determine a communication characteristic for the tag signal based on identification of the reader by the tag, the logic further configured to control the tag signal in accordance with the communication characteristic for enabling the tag signal to be received by the identified reader such that the tag signal emulates a transmission from a passive tag to the identified reader for responding to the received at least one interrogation signal,

wherein the communication characteristic pertains to a timing of the tag signal, wherein the logic is configured to transmit the tag signal after a predefined delay from reception of the at least one interrogation signal received from the identified reader such that the identified reader receives the tag signal within an expected time window for receiving a response to the received at least one interrogation signal.

2. The active tag of claim 1, wherein the logic is configured to determine a signal strength of the tag signal based on a received signal strength of the at least one interrogation signal received from the identified reader.

3. The active tag of claim 1, wherein the logic is configured to communicate with a plurality of nodes of a wireless network of an asset tracking system for determining a location of the active tag.

4. The active tag of claim 3, wherein the logic is configured to determine whether to transmit the tag signal in response to the received at least one interrogation signal based on the determined location.

5. The active tag of claim 1, wherein the logic is configured to automatically discover a frequency of the received at least one interrogation signal.

6. The active tag of claim 3, wherein the logic is configured to control a transmit power for the tag signal based on the determined location.

7. The active tag of claim 6, wherein the transmit power for the tag signal is based on a distance of the active tag from the identified reader.

8. The active tag of claim 3, wherein the logic is configured to determine the predefined delay based on the determined location.

9. The active tag of claim 8, wherein the logic is configured to determine the predefined delay based on a distance of the active tag from the identified reader.

10. A method for emulating passive tags when communicating with readers of a passive-tag identification system, the readers configured to wirelessly transmit interrogation signals for interrogating passive tags within the passive-tag identification system, the passive tags configured to wirelessly transmit tag signals in response to the interrogation signals, the tag signals including tag identifiers for identifying the passive tags, the method comprising:

receiving an interrogation signal from a reader of the passive-tag identification system via an active tag;

identifying the reader at the active tag based on communication between the active tag and the reader;

transmitting a tag signal from the active tag to the identified reader after a predefined delay from the receiving such that the identified reader receives the tag signal within an expected time window for receiving a response to the received interrogation signal;

automatically determining a communication characteristic for the tag signal based on the identifying such that the tag signal emulates a transmission from a passive tag to the identified reader for responding to the received interrogation signal, wherein the communication characteristic pertains to a timing of the tag signal; and

controlling the tag signal in accordance with the communication characteristic based on the determining thereby enabling the tag signal to be received by the identified reader.

11. The method of claim 10, further comprising:

wirelessly communicating between the active tag and a plurality of nodes of a wireless network; and

determining a location of the tag based on the communicating between the active tag and the plurality of nodes.

12. The method of claim 11, further comprising:

storing, in memory, data indicating a plurality of interrogation-enabled zones for the active tag;

determining, based on the data and the determined location of the tag, whether the tag is within one of the interrogation-enabled zones; and

determining whether to transmit the tag signal from the active tag based on whether the tag is determined to be within at least one of the interrogation-enabled zones.

13. A communication system, comprising:

a reader configured to wirelessly transmit interrogation signals for interrogating passive tags; and

an active tag configured to receive at least one of the interrogation signals and to wirelessly transmit a tag signal in response to the at least one of the interrogation signals, the active tag further configured to identify the reader based on the at least one of the interrogation signals received by the active tag and to determine a delay for responding to the at least one of the interrogation signals based on identification of the reader by the active tag, the active tag further configured to control a timing of transmission of the tag signal based on the delay such that the reader receives the tag signal within an expected time window for receiving a response to the at least one of the interrogation signals thereby emulating a transmission from a passive tag to the reader.

14. The system of claim 13, wherein the active tag is configured to determine whether to transmit the tag signal in response to the at least one of the interrogation signals based on a location of the active tag relative to the reader.

15. The system of claim 13, further comprising a server configured to determine a location of the active tag based on communications between the active tag and nodes of a network, the server configured to control, based on the location, whether the active tag transmits the tag signal in response to the at least one of the interrogation signals.

16. The system of claim 15, wherein the server is configured to store data in memory, the data indicating a plurality of interrogation-enabled zones for the active tag, wherein the server is configured to determine whether the active tag is in at least one of the interrogation-enabled zones based on the location, and wherein the server is configured to control whether the active tag transmits the tag signal in response to the at least one of the interrogation signals based on the whether the active tag is determined to be within at least one of the interrogation-enabled zones.

17. An active tag for emulating passive tags when communicating with readers of a passive-tag identification system, the readers configured to wirelessly transmit interrogation signals for interrogating passive tags within the passive-tag identification system, the passive tags configured to wirelessly transmit tag signals in response to the interrogation signals, the active tag comprising:

a communication module for communicating with the readers, the communication module configured to receive at least one interrogation signal from a reader of the passive-tag identification system;

a power supply for powering components of the active tag; and

logic configured to identify the reader based on the received at least one interrogation signal, the logic configured to wirelessly transmit a tag signal via the communication module in response to the received at least one interrogation signal, the logic configured to determine a delay for responding to the received at least one interrogation signal based on identification of the reader by the tag, the logic further configured to control a timing of transmission of the tag signal based on the delay such that the identified reader receives the tag signal within an expected time window for receiving a response to the received at least one interrogation signal thereby emulating a transmission from a passive tag to the identified reader.

18. The active tag of claim 17, wherein the logic is configured to determine the delay based on a distance of the active tag from the identified reader.

19. A method for emulating passive tags when communicating with readers of a passive-tag identification system, the readers configured to wirelessly transmit interrogation signals for interrogating passive tags within the passive-tag identification system, the passive tags configured to wirelessly transmit tag signals in response to the interrogation signals, the method comprising:

receiving at least one interrogation signal from a reader of the passive-tag identification system via an active tag;

transmitting a tag signal from the active tag to the reader in response to the received at least one interrogation signal;

identifying the reader at the active tag based on the received at least one interrogation signal;

automatically determining at the active tag a delay for responding to the received at least one interrogation signal based on the identifying; and

controlling a timing of the transmitting at the active tag based on the delay such that the identified reader receives the tag signal within an expected time window for receiving a response to the received at least one interrogation signal thereby enabling the tag signal to be received by the identified reader.

20. The method of claim 19, wherein the determining is based on a distance of the active tag from the identified reader.