Method and apparatus for tracking mobile devices using tags

• US 6,720,888 B2
• Filed: 04/24/2001
• Issued: 04/13/2004
• Est. Priority Date: 09/07/2000
• Status: Expired due to Term

• Current Assignee: Savi Technology Incorporated
• Original Assignee: Savi Technology Incorporated
• Inventors: Eagleson, James G., Blasdell, William E., Anderson, III, Arthur E., Cargonja, Nikola
• Primary Examiner(s): Crosland, Donnie L.
• Application Number:
  US09/841,782
• Publication Number:
  US 20020057192A1
• Time in Patent Office: 1,085 Days
• Field of Search: 340/905, 340/993, 340/988, 340/994, 340/10.1, 340/10.3, 340/10.33, 340/10.34, 340/10.51, 340/10.4, 340/10.41, 340/10.42, 340/10.5, 340/572.1, 340/505, 340/825.36, 340/825.49, 342/357.07, 342/450, 342/457, 235/375, 235/382, 235/381, 235/384, 700/229
• US Class Current: 340/905
• CPC Class Codes: G06K 17/0022 arrangements or provisious for transferring data to distant stations, e.g. from a sensing device "transfer between computer elements G06F13/00 "; data-transmission H04L

Abstract

A signpost (11, 241-256, 322, 612, 623, 626-628, 652, 661, 682, 686, 703) transmits low frequency signals to a beacon tag (12, 271-275, 301-316, 395-397, 616-618, 641-643, 653, 656-657, 662-664, 679, 708, 711), which in turns transmits high frequency signals containing a signpost code from a received signpost signal to a reader (13, 261, 319, 521-530). The signpost can be mounted on one mobile device and the beacon tag on another mobile device, in order to determine when those mobile devices are in close proximity. Further, a sensor (32) can be provided to detect the presence of a mobile device, and to cause the signpost to change the signpost code in its transmitted signals.

Claims

1. An apparatus comprising:

a tag having circuitry which includes a receiver section and a transmitter section, said receiver section being operable to receive wireless signpost signals that each include a signpost code, and said transmitter section being operable to transmit wireless beacon signals which each include a beacon code associated with said tag, said transmitter section being responsive to receipt by said receiver section of a respective said signpost signal for including in at least one said beacon signal the signpost code from the received signpost signal;

a signpost which is physically separate from said tag and which transmits said signpost signals to said tag;

a reader which is physically separate from said signpost and said tag, and which receives said beacon signals;

a mobile device;

an item removably supported on said mobile device, said item having said tag disposed thereon, and said signpost being stationarily supported near a path of travel of said mobile device so that said tag passes through a transmission range of said signpost signals from said signpost as said mobile device travels past said signpost with said item thereon; and

a sensor supported near said path of travel of said mobile device for detecting proximity to said sensor of one of said item and said mobile device, said signpost being operatively coupled to said sensor and being responsive to detection by said sensor of the proximity of said one of said item and mobile device for effecting a change in said signpost code of said signpost.

2. A method, comprising the steps of:

transmitting signpost signals from a signpost, each said signpost signal having a signpost code;

receiving said signpost signals in a receiver section of circuitry of a tag which is physically separate from said signpost;

transmitting from a transmitter section of said circuitry of said tag wireless beacon signals which each include a beacon code associated with said tag, said transmitting step including the step of causing said transmitter section to be responsive to receipt by said receiver section of a respective said signpost signal for including in at least one said beacon signal the signpost code from the received signpost signal;

receiving said beacon signals in a reader which is physically separate from said signpost and said tag;

removably supporting on a mobile device an item having said tag disposed thereon;

stationarily supporting said signpost near a path of travel of said mobile device in a manner so that said tag passes through a transmission range of said signpost signals from said signpost as said mobile device travels past said signpost with said item thereon;

supporting near said path of travel of said mobile device a sensor which is operatively coupled to said signpost;

detecting proximity to said sensor of one of said item and said mobile device; and

responding to detection by said sensor of the proximity of said one of said item and said mobile device for effecting a change in said signpost code of said signpost.

3. An apparatus comprising:

a tag having circuitry which includes a receiver section and a transmitter section, said receiver section being operable to receive wireless signpost signals that each include a signpost code, and said transmitter section being operable to transmit wireless beacon signals which each include a beacon code associated with said tag, said transmitter section being responsive to receipt by said receiver section of a respective said signpost signal for including in at least one said beacon signal the signpost code from the received signpost signal;

a signpost which is physically separate from said tag and which transmits said signpost signals to said tag; and

a reader which is physically separate from said signpost and said tag, and which receives said beacon signals;

a mobile device having said signpost thereon; and

an item which is removably supported on said mobile device, said item having said tag disposed thereon at a location so that said tag is within a transmission range of said signpost signals from said signpost while said item is removably supported on said mobile device.

4. An apparatus according to claim 3, including a further item which is removably supported on said mobile device, and a further tag, said further item having said further tag disposed thereon at a location so that said further tag is within a transmission range of said signpost signals from said signpost while said further item is removably supported on said mobile device, said further tag having circuitry that includes a receiver section and a transmitter section, said receiver section of said further tag being operable to receive wireless signpost signals that each include a signpost code, and said transmitter section of said further tag being operable to transmit wireless beacon signals which each include a unique beacon code associated with said further tag, said transmitter section of said further tag being responsive to receipt by said receiver section thereof of a respective said signpost signal for including in at least one said beacon signal thereof the signpost code from the received signpost signal.

5. An apparatus according to claim 3, including a further signpost stationarily supported near a path of travel of said mobile device and operable to transmit signpost signals which each include a signpost code unique to said further signpost, and a further tag supported on said mobile device at a location so that said further tag is outside a transmission range of said signpost signals from said signpost on said mobile device, and so that said further tag passes within a transmission range of said signpost signals from said further signpost as said mobile device travels past said further signpost, said further tag having circuitry that includes a receiver section and a transmitter section, said receiver section of said further tag being operable to receive wireless signpost signals that each include a signpost code, and said transmitter section of said further tag being operable to transmit wireless beacon signals which each include a unique beacon code associated with said further tag, said transmitter section of said further tag being responsive to receipt by said receiver section thereof of a respective said signpost signal for including in at least one said beacon signal thereof the signpost code from the received signpost signal.

6. A method, comprising the steps of:

transmitting signpost signals from a signpost, each said signpost signal including a signpost code;

receiving said signpost signals in a receiver section of circuitry of a tag which is physically separate from said signpost;

transmitting from a transmitter section of said circuitry of said tag wireless beacon signals which each include a beacon code associated with said tag, said transmitting step including the step of causing said transmitter section to be responsive to receipt by said receiver section of a respective said signpost signal for including in at least one said beacon signal the signpost code from the received signpost signal;

receiving said beacon signals in a reader which is physically separate from said signpost and said tag;

supporting said signpost on a mobile device; and

removably supporting on said mobile device an item having said tag disposed thereon at a location so that said tag is within a transmission range of said signpost signals from said signpost while said item is removably supported on said mobile device.

7. An apparatus according to claim 6, including the steps of:

removably supporting on said mobile device a further item having a further tag disposed thereon at a location so that said further tag is within a transmission range of said signpost signals from said signpost while said further item is removably supported on said mobile device;

receiving said signpost signals in a receiver section of circuitry of said further tag;

transmitting from a transmitter section of said circuitry of said further tag wireless beacon signals which each include a beacon code associated with said further tag, said transmitting step including the step of causing said transmitter section of said further tag to be responsive to receipt by said receiver section thereof of a respective said signpost signal for including in at least one said beacon signal of said further tag the signpost code from the received signpost signal; and

receiving said beacon signals from said further tag in said reader.

8. An apparatus according to claim 6, including the steps of:

stationarily supporting a further signpost near a path of travel of said mobile device;

transmitting from said further signpost further signpost signals which each include a signpost code unique to said further signpost;

supporting a further tag on said mobile device at a location so that said further tag is outside a transmission range of said signpost signals from said signpost on said mobile device, and so that said further tag passes within a transmission range of said signpost signals from said further signpost as said mobile device travels past said further signpost;

receiving said further signpost signals in a receiver section of circuitry of said further tag;

transmitting from a transmitter section of said circuitry of said further tag wireless beacon signals which each include a beacon code associated with said further tag, said transmitting step including the step of causing said transmitter section of said further tag to be responsive to receipt by said receiver section thereof of a respective said signpost signal from said further signpost for including in at least one said beacon signal of said further tag the signpost code from the received signpost signal; and

receiving said beacon signals from said further tag in said reader.

9. An apparatus comprising:

a tag having circuitry which includes a receiver section and a transmitter section, said receiver section being operable to receive wireless signpost signals that each include a signpost code, and said transmitter section being operable to transmit wireless beacon signals which each include a beacon code associated with said tag, said transmitter section being responsive to receipt by said receiver section of a respective said signpost signal for including in at least one said beacon signal the signpost code from the received signpost signal;

a signpost which is physically separate from said tag and which transmits said signpost signals to said tag; and

a reader which is physically separate from said signpost and said tag, and which receives said beacon signals; and

first and second mobile devices which are releasably coupled to each other, said signpost being provided on one of said mobile devices and said tag being provided on the other of said mobile devices, said signpost and said tag being positioned on said mobile devices so that said tag is within a transmission range of said signpost signals from said signpost.

10. An apparatus according to claim 9, including a control section which is coupled to said reader, and which is responsive to information in said beacon signals received from said tag through said reader for determining that said first and second mobile devices are currently coupled to each other.

11. An apparatus according to claim 10,

wherein said first and second mobile devices are operatively coupled in a manner so that a rear end of said first mobile device is adjacent a forward end of said second mobile device; and

wherein said control section is operable for determining that said first mobile device precedes said second mobile device in a direction of travel of said mobile devices.

12. An apparatus according to claim 11, wherein said first mobile device includes a drive mechanism for effecting movement of said first mobile device, and wherein said second mobile device is a trailer.

13. An apparatus according to claim 11, wherein said first and second mobile devices are each a trailer.

14. An apparatus according to claim 10,

including a plurality of tags which each have circuitry that includes a receiver section and a transmitter section, said receiver section of each of said plurality of tags being operable to receive wireless signpost signals that each include a signpost code, and said transmitter section of each of said plurality of tags being operable to transmit wireless beacon signals which each include a beacon code unique to the associated tag, said transmitter section of each of said plurality of tags being responsive to receipt by said receiver section thereof of a respective said signpost signal for including in at least one said beacon signal thereof the signpost code from the received signpost signal, said plurality of tags including first and second tags and said first tag being said tag on said other of said first and second mobile devices;

and

including a plurality of signposts which are physically separate from said tags and from each other, and which each transmit respective signpost signals that each include a respective signpost code unique to the associated signpost, said plurality of signposts including first and second signposts and said first signpost being said signpost on said one of said first and second mobile devices.

15. An apparatus according to claim 14,

wherein said first mobile device has thereon said second tag at a location outside a transmission range of said first signpost;

and

wherein said second signpost is stationarily supported near a path of travel of said mobile devices in a manner so that, as said mobile devices pass said second signpost, said second tag is within and said first tag is outside a transmission range of said signpost signals from said second signpost.

16. An apparatus according to claim 15, wherein said first mobile device includes a drive mechanism for effecting movement of said first mobile device, and wherein said second mobile device is a trailer.

17. An apparatus according to claim 14, including an item removably supported on said other of said mobile devices, said item having thereon said second tag at a location within a transmission range of said signpost signals from said first signpost.

18. An apparatus according to claim 17, wherein said item has thereon a third tag from said plurality of tags at a location outside a transmission range of said first signpost;

and wherein said second signpost is stationarily supported near a path of travel of said mobile devices in a manner so that, as said mobile devices pass said second signpost, said third tag is within and said first and second tags are outside a transmission range of said signpost signals from said second signpost.

19. An apparatus according to claim 18,

wherein a third signpost from said plurality of signposts is provided on said one of said mobile devices at a location so that said first tag thereon is outside a transmission range of said signpost signals from said third signpost;

including a further item removably supported on said one of said mobile devices, said further item having thereon a fourth tag from said plurality of tags at a location within a transmission range of said signpost signals from said third signpost;

wherein said further item has thereon a fifth tag from said plurality of tags at a location outside a transmission range of said first and third signposts; and

wherein as said mobile devices pass said second signpost, said fifth tag is within and said fourth tag is outside a transmission range of said signpost signals from said second signpost.

20. An apparatus according to claim 17, wherein said item is a container which can removably receive a plurality of other items.

21. An apparatus according to claim 14,

wherein said one of said mobile devices has thereon said second tag at a location so that said second tag is outside a transmission range of said signpost signals from said first signpost;

and

wherein said other of said mobile devices has thereon said second signpost at a location so that said first tag is outside a transmission range of said signpost signals from said second signpost.

22. An apparatus according to claim 14,

including a third mobile device releasably coupled to said second mobile device in a manner so that so that a rear end of said second mobile device is adjacent a forward end of said third mobile device;

wherein said second signpost is provided on one of said second and third mobile devices, and said second tag is provided on the other of said second and third mobile devices in a manner so that said second mobile device has thereon one of said first and second signposts and also one of said first and second tags at a location outside a transmission range of said one of said signposts, said second tag and said second signpost being positioned on said second and third mobile devices so that said second tag is within a transmission range of said signpost signals from said second signpost; and

wherein said control section is responsive to information in said beacon signals received from said first and second tags through said reader for determining that said second and third mobile devices are currently coupled to each other, and that said first mobile device precedes said second mobile device and said second mobile device precedes said third mobile device in a direction of travel of said mobile devices.

23. A method, comprising the steps of:

transmitting signpost signals from a signpost, said signpost signals each including a signpost code;

receiving said signpost signals in a receiver section of circuitry of a tag which is physically separate from said signpost;

transmitting from a transmitter section of said circuitry of said tag wireless beacon signals which each include a beacon code associated with said tag, said transmitting step including the step of causing said transmitter section to be responsive to receipt by said receiver section of a respective said signpost signal for including in at least one said beacon signal the signpost code from the received signpost signal;

receiving said beacon signals in a reader which is physically separate from said signpost and said tag;

releasably coupling first and second mobile devices to each other; and

supporting said signpost on one of said mobile devices and said tag on the other thereof, in a manner so that said tag is within a transmission range of said signpost signals from said signpost while said mobile devices are releasably coupled.

24. A method according to claim 23, including the steps of:

providing a control section which is coupled to said reader; and

determining in said control section that said first and second mobile devices are currently coupled to each other in response to information in said beacon signals received from said tag through said reader.

25. A method according to claim 24,

wherein said step of releasably coupling said first and second mobile devices is carried out in a manner so that a rear end of said first mobile device is adjacent a forward end of said second mobile device;

and

wherein said determining step includes the step of determining that said first mobile device precedes said second mobile device in a direction of travel of said mobile devices.

26. A method according to claim 25, including the step of selecting as said first mobile device a mobile device which includes a drive mechanism for effecting movement of said first mobile device, and including the step of selecting as said second mobile device a trailer.

27. A method according to claim 25, including the step of selecting said first and second mobile devices to each be a trailer.

28. A method according to claim 24, including the steps of:

providing a plurality of tags which each have circuitry that includes a receiver section and a transmitter section, said receiver section of each of said plurality of tags being operable to receive wireless signpost signals that each include a signpost code, and said transmitter section of each of said plurality of tags being operable to transmit wireless beacon signals which each include a beacon code unique to the associated tag, said transmitter section of each of said plurality of tags being responsive to receipt by said receiver section thereof of a respective said signpost signal for including in at least one said beacon signal thereof the signpost code from the received signpost signal, said plurality of tags including first and second tags and said first tag being said tag on said other of said first and second mobile devices; and

providing a plurality of signposts which are physically separate from said tags and from each other, and which each transmit respective signpost signals that each include a respective signpost code unique to the associated signpost, said plurality of signposts including first and second signposts and said first signpost being said signpost on said one of said first and second mobile devices.

29. A method according to claim 28, including the steps of:

supporting said second tag on said first mobile device at a location outside a transmission range of said first signpost; and

stationarily supporting said second signpost near a path of travel of said mobile devices in a manner so that, as said mobile devices pass said second signpost, said second tag is within and said first tag is outside a transmission range of said signpost signals from said second signpost.

30. A method according to claim 29, including the steps of:

selecting as said first mobile device a mobile device which includes a drive mechanism for effecting movement of said first mobile device; and

selecting as said second mobile device a trailer.

31. A method according to claim 28, including the step of removably supporting on said other of said mobile devices an item having said second tag thereon at a location within a transmission range of said signpost signals from said first signpost.

32. A method according to claim 31, including the steps of:

supporting on said item at a location outside a transmission range of said first signpost a third tag from said plurality of tags; and

stationarily supporting said second signpost near a path of travel of said mobile devices in a manner so that, as said mobile devices pass said second signpost, said third tag is within and said first and second tags are outside a transmission range of said signpost signals from said second signpost.

33. A method according to claim 32, including the steps of:

supporting a third signpost from said plurality of signposts on said one of said mobile devices at a location so that said first tag thereon is outside a transmission range of said signpost signals from said third signpost;

removably supporting on said one of said mobile devices a further item having a fourth tag from said plurality of tags thereon at a location within a transmission range of said signpost signals from said third signpost; and

supporting a fifth tag from said plurality of tags on said further item at a location outside a transmission range of said first and third signposts;

wherein as said mobile devices pass said second signpost, said fifth tag is within and said fourth tag is outside a transmission range of said signpost signals from said second signpost.

34. A method according to claim 31, including the step of selecting as said item a container which can removably receive a plurality of other items.

35. A method according to claim 28, including the step of:

supporting said second tag on said one of said mobile devices at a location so that said second tag is outside a transmission range of said signpost signals from said first signpost; and

supporting said second signpost on said other of said mobile devices at a location so that said first tag is outside a transmission range of said signpost signals from said second signpost.

36. A method according to claim 28, including the steps of:

releasably coupling a third mobile device to said second mobile device in a manner so that a rear end of said second mobile device is adjacent a forward end of said third mobile device;

supporting said second signpost on one of said second and third mobile devices, and said second tag on the other of said second and third mobile devices, in a manner so that said second mobile device has thereon one of said first and second signposts and also one of said first and second tags at a location outside a transmission range of said one of said signposts, said second tag and said second signpost being positioned on said second and third mobile devices so that said second tag is within a transmission range of said signpost signals from said second signpost; and

determining in said control section in response to information in said beacon signals received from said first and second tags through said reader that said second and third mobile devices are currently coupled to each other, that said first mobile device precedes said second mobile device in a direction of travel of said mobile devices, and that said second mobile device precedes said third mobile device in a direction of travel of said mobile devices.