Electronic tether for portable objects

• US 20060197658A1
• Filed: 02/23/2006
• Published: 09/07/2006
• Est. Priority Date: 06/09/2000
• Status: Active Grant

• Current Assignee: Dot Holdings, LLC
• Original Assignee: Jebsec LLC
• Inventors: Roberts, Jon L., Light, Elliott D., Boesch, Brian
• Granted Patent: US 7,375,638 B2
• Time in Patent Office: Days
• US Class Current: 340/539.23
• CPC Class Codes: G08B 13/1427 with transmitter-receiver for distance detection
• CPC Class Codes: G08B 13/2417 having a radio frequency identification chip

Abstract

A system and method for issuing an alarm when the separation distance between a monitoring module associated with an object (animate or inanimate) and an alert module exceeds a preset threshold distance thereby forming a leadless electronic tether between the object and the object owner. A monitoring module comprises a portable transmitter provides a signal to an alert module comprising a receiver and a processor. The alert module is adapted to determine a separation distance between the monitoring module and the alert module based on an attribute of the signal. When the separation distance exceeds a predetermined threshold, the alert module issues an alert. Alternatively, when the monitoring module signal is not received by the alert module, an alert is issued.

Claims

1. An electronic tether comprising:

a monitoring module associated with a monitored object, wherein the monitoring module comprises an RFID tag adapted for receiving a polling signal and for transmitting a reflected signal in response to the polling signal, wherein the reflected signal comprises an RFID tag identifier unique to the RFID tag; and

an alert module comprising;

a memory comprising the RFID tag identifier;

an RFID tag polling manager adapted for sending the polling signal;

a receiver adapted for receiving the reflected signal from the RFID tag;

a separation manager adapted for;

determining whether the reflected signal comprising the RFID tag identifier has been received; and

issuing an “

object not present”

alert if the reflected signal comprising the RFID tag has not been received.

5. The electronic tether of claim 1, wherein the object not present alert is an audible alarm.

6. The electronic tether of claim 5, wherein the audible alarm is a synthesized voice.

7. The electronic tether of claim 1, wherein the object not present alert is a visual alarm.

8. The electronic tether of claim 7, wherein the visual alarm is a text message.

9. The electronic tether of claim 1, wherein the object not present alert identifies the monitored object that is associated with the monitoring module.

10. The electronic tether of claim 1, wherein the alert module is further adapted for:

accepting an object not present alert cancel request from a user;

determining whether a reflected signal comprising the RFID tag identifier has been received; and

issuing an object return alert if the reflected signal comprising the RFID tag identifier has not been received.

11. The electronic tether of claim 1, wherein the alert module is incorporated into a portable device.

12. The electronic tether of claim 11, wherein the portable device is selected from the group consisting of a cellular telephone, a PDA, a laptop computer, a portable music player, and a wristwatch.

13. The electronic tether of claim 1, wherein the polling manager comprises means for varying the polling signal signal strength.

14. The electronic tether of claim 13, wherein the monitoring module is further adapted for establishing a preset separation distance between the alert module and the monitoring module by adjusting the polling signal signal strength.

15. The electronic tether of claim 1, wherein the receiver comprises means for varying the receiver sensitivity to the reflected signal.

16. The electronic tether of claim 15, wherein the monitoring module is further adapted for establishing a preset separation distance between the alert module and the monitoring module by adjusting the receiver sensitivity.

17. The electronic tether of claim 1, wherein a preset separation distance is established by selection of the RFID tag based on a measure of signal strength of the reflected signal.

18. The electronic tether of claim 1, wherein the RFID tag is selected from the group consisting of a passive RFID tag, a semi-passive RFID tag, and an active RFID tag.

19. The electronic tether of claim 1, wherein the alert module is further adapted for:

in response to the object not present alert, identifying the RFID tag as non-responsive;

resending the polling signal to the non-responsive RFID tag; and

if the non-responsive RFID tag fails to respond after a preset number of resend attempts, then issuing an alarm.

20. The electronic tether of claim 1, wherein the alert module is further adapted for:

in response to the object not present alert, identify the RFID tag as non-responsive;

increasing the polling signal signal strength by a preset increment;

resending the polling signal to the non-responsive RFID tag; and

if the non-responsive RFID tag fails to respond after polling signal signal strength reaches a maximum signal strength level, then issue an alarm with respect to the RFID tag.

21. The electronic tether of claim 1, wherein the alert module is further adapted for:

in response to the object not present alert, identifying the RFID tag as non-responsive;

increasing the receiver sensitivity by a preset increment;

resending the polling signal to the non-responsive RFID tag; and

if the non-responsive RFID tag fails to respond after receiver sensitivity reaches a maximum sensitivity, then issuing an alarm with respect to the RFID tag.

2. A method for monitoring an object using an alert module comprising:

associating an RFID tag identifier with an object and storing the RFID tag identifier in the alert module;

sending a polling signal from the alert module module;

receiving a polling signal at a monitoring module associated with a monitored object,

wherein the monitoring module comprises an RFID tag;

transmitting a reflected signal from the RFID tag in response to the polling signal,

wherein the reflected signal comprises an identifier unique to the RFID tag;

determining whether a reflected signal from the RFID tag comprising the RFID tag identifier is received at the alert module; and

issuing an “

object not present”

alert from the alert module with respect to the object if the RFID tag identifier associated with the object is not received.

3. An identification system comprising:

a sonic identification tag, wherein the sonic identification tag comprises a piezoelectric sensor, a power storage unit, a transmission circuit and a tag identifier, and wherein the sonic identification tag is adapted for;

receiving a sonic polling signal;

generating an electric current in response to the sonic polling signal;

storing an electric charge in the power storage unit; and

sending a response signal from the transmission circuit, wherein the response signal comprises the tag identifier;

a sonic polling signal generator, wherein the sonic polling signal generator is adapted for;

sending the sonic polling signal;

receiving the response signal from the sonic identification tag; and

determining the tag identifier from the response signal.

4. A method of identifying an object comprising:

sending a sonic polling signal from a sonic polling signal generator;

receiving a sonic polling signal at a sonic identification tag;

generating an electric current in response to the sonic polling signal;

storing an electric charge in the power storage unit;

sending a response signal from the transmission circuit, wherein the response signal comprises a sonic tag identifier;

receiving the response signal from sonic identification tag; and

determining the tag identifier from the response signal.

22. An electronic tether comprising:

a monitoring module comprising a first and second RFID tags adapted to receive a polling signal and to transmit a first reflected signal and a second reflected signal in response to the polling signal, wherein the first reflected signal comprises an first identifier unique to the first RFID tag and the second reflected signal comprises an second identifier unique to the second RFID tag; and

an alert module comprising;

a memory comprising the first and second RFID tag identifiers;

an RFID tag polling manager adapted to send the polling signal;

a receiver adapted for receiving the first and second reflected signals from the first and second RFID tags;

an separation manager adapted for;

determining whether the first reflected signal comprising the first RFID tag identifier has been received; and

issuing a first “

object not present”

alert with respect to the first alert module if the first reflected signal comprising the first RFID tag has not been received;

determining whether the second reflected signal comprising the second RFID tag identifier has been received; and

issuing a second “

object not present”

alert with respect to the second alert module if the second reflected signal comprising the second RFID tag has not been received.

23. The electronic tether of claim 22, wherein the first object not present alert and the second not present alert is an audible alarm.

24. The electronic tether of claim 23, wherein the audible alarm is a synthesized voice.

25. The electronic tether of claim 22, wherein the first object not present alert and second not present alert ale visual alarms.

26. The electronic tether of claim 25, wherein a visual alarm is a text message.

27. The electronic tether of claim 22, wherein the first object not present alert identifies the monitored object that is associated with the first monitoring module.

28. The electronic tether of claim 22, wherein the alert module is further adapted for:

accepting a first object not present alert cancel request from a user with respect to the first alert module;

determining whether a first reflected signal comprising the first RFID tag identifier has been received; and

issuing an object return alert with respect to the first alert module if the first reflected signal comprising the first RFID tag identifier has been received.

29. The electronic tether of claim 22, wherein the alert module is incorporated into a portable device.

30. The electronic tether of claim 29, wherein the portable device is selected from the group consisting of a cellular telephone, a PDA, a laptop computer, a portable music player, and a wristwatch.

31. The electronic tether of claim 22, wherein the polling manager comprises means for varying the polling signal signal strength.

32. The electronic tether of claim 31, wherein monitoring module is further adapted for establishing a preset separation distance between the alert module and the monitoring module by adjusting the polling signal signal strength.

33. The electronic tether of claim 22, wherein the receiver comprises means for varying the receiver sensitivity to the reflected signal.

34. The electronic tether of claim 33, wherein the monitoring module is further adapted for establishing a preset separation distance between the alert module and the monitoring module by adjusting the receiver sensitivity.

35. The electronic tether of claim 22, wherein the at least first and second RFID tags are selected from the group consisting of a passive RFID tag, a semi-passive RFID tag, and an active RFID tag.

36. The electronic tether of claim 22, wherein the alert module is further adapted for:

in response to the first object not present alert, identifying the first RFID tag as non-responsive;

resending the polling signal to the first RFID tag; and

if the non-responsive first RFID tag fails to respond after a preset number of resend attempts, then issuing an alarm.

37. The electronic tether of claim 22, wherein the alert module is further adapted for:

in response to the first object not present alert, identifying the first RFID tag as non-responsive;

increasing the polling signal signal strength by a preset increment;

resending the polling signal to the non-responsive RFID tag; and

if the non-responsive RFID tag fails to respond after polling signal signal strength reaches a maximum signal strength level, then issuing an alarm with respect to the first RFID tag.

38. The electronic tether of claim 22, wherein the alert module is further adapted to:

in response to the first object not present alert, identifying an RFID tag as non-responsive;

increasing the receiver sensitivity by a preset increment;

resending the polling signal to the non-responsive RFID tag; and

if the non-responsive RFID tag fails to respond after receiver sensitivity reaches a maximum sensitivity, then issuing an alarm with respect to the first RFID tag.

39. The electronic tether of claim 22, wherein:

a first preset preset separation distance is established by selection of the first RFID tag; and

a second preset preset separation distance is established by selection of the RFID tag.