Real-time RFID positioning system and method, repeater installation method therefor, position confirmation service system using the same

• US 8,502,670 B2
• Filed: 10/20/2007
• Issued: 08/06/2013
• Est. Priority Date: 10/20/2006
• Status: Expired due to Fees

• Current Assignee: KT Corporation
• Original Assignee: KT Corporation
• Inventors: Cha, Maeng-Q, Seo, Myung-Woo, Baik, Song-Hoon
• Primary Examiner(s): DINH, KHANH Q
• Application Number:
  US12/446,258
• Publication Number:
  US 20100295943A1
• Time in Patent Office: 2,117 Days
• Field of Search: 340/572.1, 340/506
• US Class Current: 340/572.1
• CPC Class Codes: G01S 13/82 wherein continuous-type signals are transmitted
• CPC Class Codes: G01S 13/878 Combination of several spaced transmitters or receivers of known location for determining the position of a transponder or a reflector G01S13/874 takes precedence
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management
• CPC Class Codes: Y02A 30/60 Planning or developing urban green infrastructure

Abstract

Provided are to a real-time RFID location determination system for accurately determining a location of a mobile object using radio frequency identification (RFID) in real-time, a method thereof, and a method for installing a wireless repeater such as a RFID reader or a RFID reader and an access point (AP) using the same. The location determination system includes: a wireless repeater for identifying a radio frequency identification (RFID) tag by communicating with the RFID tag attached or installed at a target object to determine a location thereof, wherein the wireless repeater is installed a urban facility and a location of the target object is determined based on a coordinate of a corresponding urban facility as a reference point.

Claims

1. A system for determining a location of a mobile object in real-time, comprising:

a wireless repeater for identifying a radio frequency identification (RFID) tag by communicating with the RFID tag attached or installed at a target object to determine a location thereof,

wherein the wireless repeater is installed at an urban facility and a location of the target object is determined based on a coordinate of a corresponding urban facility as a reference location point, and

wherein the location of the target object is determined based on a time of arrival (ToA) of a signal transmitted from the RFID tag, an attenuation of the signal, a direction of arrival (DoA) of the signal, and a time difference of arrival (TDoA) of the signal.

2. The system of claim 1, wherein the wireless repeater stores a coordinate of own urban facility and coordinates of urban facilities having adjacent wireless repeaters in a form of a database.

6. The system of claims 1, wherein the reference location points are obtained using a digital map produced for a geographic information system (GIS).

7. The system of claim 6, wherein the wireless repeater includes at least three RFID readers.

8. The system of claim 7, wherein at least three of the RFID readers form a single raw triangle structure by being installed at the urban facilities.

9. The system of claim 8, wherein the single raw triangle structure is formed by one RFID reader installed at an urban facility disposed at one side of a street and two RFID readers installed at urban facilities disposed at the other side.

10. The system of claim 7, wherein the wireless repeater further includes an access point (AP) connected to the RFID reader.

11. The system of claim 6, wherein in determining a location of the target object, a location of the RFID tag is calculated from coordinates stored in the database based on a cell ID of the wireless repeater.

12. The system of claim 6, wherein in determining a location of the target object, a distance between the wireless repeater and the RFID tag is calculated using a time of arrival (ToA) of a signal transmitted from the RFID tag to the wireless repeater and a location of the RFID tag is calculated based on the calculated distance and the coordinates stored in the database.

13. The system of claim 6, wherein in determining a location of the target object, an attenuation of a signal received from the RFID tag is measured, a distance between the wireless repeater and the RFID tag is calculated by applying a predetermined propagation model according to a predetermined environment, and a location of the RFID tag is calculated based on the calculated distance and the coordinates in the database.

14. The system of claim 6, wherein in determining a location of the target object, directions of arrival (DoA) of signals are estimated, and a location of the RFID tag is calculated based the crossing of the DoAs.

15. The system of claim 6, wherein in determining a location of the target object, a time difference of arrivals (TDoA) of signals is calculated and a location of the RFID tag is calculated based on crossing of cells from the calculated TDoA.

16. The system of claim 2, wherein the wireless repeater includes at least three RFID readers, and

each of the three RFID readers transmits a search signal at a regular interval, receives a response signal with identification information from the RFID tag in a propagation area of the search signal, calculates a distance to the RFID tag based on a difference between a time of transmitting the search signal and a time of receiving the received response signal from the RFID tag, and calculates a location of the RFID tag based on the calculated distance and the coordinates in the database.

18. The system of claim 1, wherein the urban facility is a streetlamp having accurate location data and capability of applying electric power.

19. The system of claim 1, wherein the location of the target objet is wirelessly transmitted to the RFID tag.

20. The system of claim 1, wherein the determined location of the target object is transmitted to at least one of a location determination server and an application service server through at least one of a wired communication network and a wireless communication network.

21. The system of claim 20, wherein the application service server is a missing child prevention service server.

24. The system of claim 7, wherein a gap between the RFID reader is about 100 m and an installation height of the RFID reader is about 3.5 m from the ground.

3. A system for determining a location of a mobile object in real-time, comprising:

a wireless repeater for identifying a radio frequency identification (RFID) tag by communicating with the RFID tag attached or installed at a target object to determine a location thereof; and

a location determination server for determining a location of the target object based on a coordinate of a corresponding urban facility having the wireless repeater as a reference location point,

wherein the location of the target object is determined based on a time of arrival (ToA) of a signal transmitted from the RFID tag, an attenuation of the signal, a direction of arrival (DoA) of the signal, and a time difference of arrival (TDoA) of the signal.

4. The system of claim 3, wherein the location determination server stores coordinates of urban facilities having the wireless repeaters as reference location points in a form of a database.

5. The system of claim 3, wherein the wireless repeater provides a coordinate of a corresponding urban facility as a reference location point to the location determination server when a location of the target object is tracked.

17. The system of claim 4, wherein the wireless repeater includes at least three RFID readers,

each of the three wireless repeater transmits a search signal at a regular interval, receives a response signal with identification information from the RFID tag in a propagation area of the search signal, calculates a distance to the RFID tag based on a difference between a time of transmitting the search signal and a time of receiving the received response signal from the RFID tag, and transmits the calculated distance to the location determination server, and

the location determination server calculates a location of the RFID tag based on the calculated distance and the coordinates in the database.

22. The system of claim 3, wherein the determined location of the target object is transmitted to the application service server through at least one of a wired communication network and a wireless communication network.

23. The system of claim 22, wherein the application service server is a missing child prevention service server.

25. A system for providing a location determination service, comprising:

a database for mapping radio frequency identification (RFID) tags provided to each subscriber to a corresponding subscriber and managing the mapped RFID tags; and

a location information providing means for classifying location information of each RFID tag, which are determined based on coordinates of urban facilities having wireless repeaters that identify the RFID tag attached or installed at a target object as reference location points, by a subscriber and providing the classified location information through a predetermined communication network set by a corresponding subscriber,

wherein the determined location information of each RFID tag is calculated based on a time of arrival (ToA) of a signal transmitted from the RFID tag, an attenuation of the signal, a direction of arrival (DoA) of the signal, and a time difference of arrival (TDoA) of the signal.

26. The system of claim 25, wherein the communication network is at least one of a wired broadcasting network, a wireless broadcasting network, a telephone network, a mobile communication network, a wired Internet, a wireless Internet, and a mobile Internet.

35. The system of claim 25, wherein the reference location points are obtained using a digital map produced by a geographic information system (GIS).

36. The system of claim 35, wherein the wireless repeater includes at least three RFID readers.

37. The system of claim 36, wherein at least three of the RFID readers form a single raw triangle structure by being installed at the urban facilities.

38. The system of claim 37, wherein the single raw triangle structure is formed by one RFID reader installed at an urban facility disposed at one side of a street and two RFID readers installed at urban facilities disposed at the other side.

39. The system of claim 36, wherein the wireless repeater further includes an access point (AP) connected to the RFID reader.

40. The system of claim 25, wherein the determined location information of each RFID tag is wirelessly transmitted to the RFID tag.

41. The system of claim 25, wherein the determined location information of each RFID tag is a value calculated from coordinates stored in the database based on a cell ID of the wireless repeater.

42. The system of claim 25, wherein the determined location information of each RFID tag is a value calculated by calculating a distance between the wireless repeater and the RFID tag using a time of arrival (ToA) of a signal transmitted from the RFID tag to the wireless repeater and calculating a location of the RFID tag based on the calculated distance and the coordinates stored in the database.

43. The system of claim 25, wherein the determined location information of each RFID tag is a value calculated by measuring an attenuation of a signal received from the RFID tag is measured, calculating a distance between the wireless repeater and the RFID tag by applying a predetermined propagation model according to a predetermined environment, and calculating a location of the RFID tag based on the calculated distance and the coordinates in the database.

44. The system of claim 25, wherein the determined location information of each RFID tag is calculated by estimating directions of arrival (DoA) of signals and calculating a location of the RFID tag based the crossing of the DoAs.

45. The system of claim 25, wherein the determined location information of each RFID tag is calculated by calculating a time difference of arrivals (TDoA) of signals and calculating a location of the RFID tag is calculated based on crossing of cells from the calculated TDoA.

46. The system of claim 25, wherein the urban facility is a streetlamp having accurate location data and capability of applying electric power.

47. The system of claim 46, wherein the database (DB) maps and manages at least one of RFID tag unique numbers provided to each subscriber and at least one of telephone numbers to transmit a warning message a predetermined event occurs.

48. The system of claim 47, wherein the warning message is transmitted when the RFID tag escapes from a tag usage area that is set when a service is subscribed, when the RFID tag escapes from a tag recognition range, when an emergency call request is received from the RFID tag, when power of the RFID tag is turned off, and when movement of the RFID tag is not sensed for a predetermined time.

49. The system of claim 48, wherein the warning message is transmitted to a previously set telephone number through a voice and/or a text message.

50. The system of claim 48, wherein when the warning message is transmitted, the location information providing means performs at least of a process of displaying a latest location of a target object in a GIS screen, a process of monitoring an area around the latest location of the target object using a CCTV camera installed at a streetlamp close to the latest location, a process of displaying description of the target object and detail of an accident through a variable message system (VMS), and a process of informing cooperated organizations such as a police station, a fire station, and patrols about the detail of an accident.

51. The system of claim 50, wherein the streetlamp further includes a CCTV camera for photographing a predetermined area in response to control of the location information providing means.

52. The system of claim 48, wherein the streetlamp further includes a horn for outputting a warning sound in response to control of the location information providing means.

53. The system of claim 47, wherein the streetlamp further includes an environmental sensor for collecting environmental information around a corresponding streetlamp and providing the collected environmental information to the location information providing means.

54. The system of claim 53, wherein the location information providing means analyzes the environmental information collected through the environmental sensor and informs a corresponding plan to a previously set telephone number or the RFID tag based on the analysis result.

55. The system of claim 47, wherein the RFID tag further includes a state measuring sensor for collecting state information of the target object and providing the collected state information to the location information providing means.

56. The system of claim 55, wherein the location information providing means analyzes the collected state information from the state measuring sensor and informs a corresponding plan to a previously set telephone number or the RFID tag based on the analysis result.

57. The system of claim 36, wherein a gap between the RFID readers is about 100 m and an installation height of the RFID reader is about 3.5 m from the ground.

27. A system for providing a location determination service comprising:

a database for mapping radio frequency identification (RFID) tags provided to each subscriber to a corresponding subscriber and managing the mapped RFID tags; and

a location information providing means for classifying location information determined by identifying each RFID tag by a subscriber and providing the classified location information through a broadcasting network,

wherein the determined location information of each RFID tag is calculated based on a time of arrival (ToA) of a signal transmitted from the RFID tag, an attenuation of the signal, a direction of arrival (DoA) of the signal, and a time difference of arrival (TDoA) of the signal.

28. The system of claim 27, wherein the location information is determined based on coordinates of urban facilities having wireless delay devices that identify the RFID tag attached or installed at a target object.

29. A system for providing a location determination service comprising:

a database for mapping radio frequency identification (RFID) tags provided to each subscriber to a corresponding subscriber and managing the mapped RFID tags; and

a location information providing means for classifying location information of each RFID tag, which is determined based on coordinates of urban facilities having wireless delay devices that identify the RFID tag attached or installed at a target object, by a subscriber and providing the classified location information through a broadcasting network,

wherein the determined location information of each RFID tag is calculated based on a time of arrival (ToA) of a signal transmitted from the RFID tag, an attenuation of the signal, a direction of arrival (DoA) of the signal, and a time difference of arrival (TDoA) of the signal.

30. A system for providing a location determination service, comprising:

a wireless repeater for identifying a RFID tag attached or installed at a target object by communicating with the RFID tag;

a database for mapping the RFID tags provided to each subscriber to a corresponding subscriber and managing the mapped RFID tags; and

a location information providing means for classifying location information of each RFID tag, which is determined based on coordinates of corresponding urban facilities having the wireless repeater by a subscriber and providing the classified location information through a broadcasting network,

wherein the determined location information of each RFID tag is calculated based on a time of arrival (ToA) of a signal transmitted from the RFID tag, an attenuation of the signal, a direction of arrival (DoA) of the signal, and a time difference of arrival (TDoA) of the signal.

31. The system of claim 30, wherein the wireless repeater stores a coordinate of own urban facility and coordinates of urban facilities having adjacent wireless repeaters in a form of a database.

32. A system for providing a location determination service, comprising:

a wireless repeater for identifying a RFID tag attached or installed at a target object by communicating with the RFID tag;

a location determination server for determining a location of each RFID tag based on coordinates of corresponding urban facilities having the wireless repeater as reference location points; and

a location information providing means for classifying the determined location information of each RFID tag by a subscriber and providing the classified location information through a broadcasting network,

wherein the determined location information of each RFID tag is calculated based on a time of arrival (ToA) of a signal transmitted from the RFID tag, an attenuation of the signal, a direction of arrival (DoA) of the signal, and a time difference of arrival (TDoA) of the signal.

33. The system of claim 32, wherein the location determination server stores coordinates of urban facilities having wireless repeaters in a form of a database.

34. The system of claim 32, wherein the wireless repeater provides coordinates of corresponding urban facilities as reference location points to the location determination server in real-time when a location of the target object is tracked.