System and methods for IP and VoIP device location determination

• US 7,961,717 B2
• Filed: 05/11/2006
• Issued: 06/14/2011
• Est. Priority Date: 05/12/2005
• Status: Active Grant

• Current Assignee: Iposi, Inc.
• Original Assignee: Iposi, Inc.
• Inventors: Lee, Richard M., Keegan, Richard
• Primary Examiner(s): Flynn; Nathan
• Assistant Examiner(s): KASSIM, KHALED M
• Application Number:
  US11/433,062
• Publication Number:
  US 20070030841A1
• Time in Patent Office: 1,860 Days
• Field of Search: 370352-356, 370/401, 455/404.1, 455/456.1, 455/558, 342/357.22, 342/357.24, 342/357.39, 701/214, 701/215
• US Class Current: 370/352
• CPC Class Codes: G01S 19/05 providing aiding data
• CPC Class Codes: G01S 19/06 employing an initial estimate of the location of the receiver as aiding data or in generating aiding data
• CPC Class Codes: G01S 19/17 Emergency applications
• CPC Class Codes: G01S 19/235 Calibration of receiver components
• CPC Class Codes: G01S 19/25 involving aiding data received from a cooperating element, e.g. assisted GPS
• CPC Class Codes: G01S 19/252 Employing an initial estimate of location in generating assistance data
• CPC Class Codes: G01S 19/42 Determining position
• CPC Class Codes: G01S 5/0027 of actual mobile position, i.e. position determined on mobile
• CPC Class Codes: H04M 2242/04 for emergency applications
• CPC Class Codes: H04M 2242/30 Determination of the location of a subscriber
• CPC Class Codes: H04M 3/42102 Making use of the called party identifier
• CPC Class Codes: H04M 3/42348 Location-based services which utilize the location information of a target
• CPC Class Codes: H04M 3/42365 Presence services providing information on the willingness to communicate or the ability to communicate in terms of media capability or network connectivity
• CPC Class Codes: H04M 7/006 Networks other than PSTN/ISDN providing telephone service, e.g. Voice over Internet Protocol (VoIP) , including next generation networks with a packet-switched transport layer H04L65/00 takes precedence; aspects not specific to the type of network H04M3/00; special services in those networks H04M3/42
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management

Abstract

A method and system for precise position determination of general Internet Protocol (IP) network-connected devices. A method enables use of remote intelligence located at strategic network points to distribute relevant assistance data to IP devices with embedded receivers. Assistance is tailored to provide physical timing, frequency and real time signal status data using general broad band communication protocols. Relevant assistance data enables several complementary forms of signal processing gain critical to acquire and measure weakened or distorted in-building Global Navigation Satellite Services (GNSS) signals and to ultimately extract corresponding pseudo-range time components. A method to assemble sets of GNSS measurements that are observed over long periods of time while using standard satellite navigation methods, and once compiled, convert using standard methods each pseudo-range into usable path distances used to calculate a precise geographic position to a known degree of accuracy.

Claims

1. A method for determining position of a device connected to a computer network relative to a fixed coordinate system, said method comprising the steps of:

estimating position of a device relative to a fixed coordinate system to a first level of accuracy by communicating over a computer network with a model server;

obtaining, by said device, data over said computer network regarding signal characteristics of a positioning system relative to said position estimated to said first level of accuracy;

providing at least one peering point server attached to said computer network, wherein time and frequency references of said at least one peering point server are calibrated to time and frequency references of said positioning system;

calibrating time and frequency references of said device to said time and frequency references of said at least one peering point server at least in part through communications over said computer network between said device and said at least one peering point servers;

aligning time and frequency elements in a receiver of said device to signal characteristics of at least one transmitter of said positioning system, wherein said signal characteristics were acquired in said obtaining step;

receiving a plurality of signals from said at least one transmitter of said positioning system,

wherein said receiving step comprises

(i) receiving a first signal of said plurality of signals from a first transmitter position at said first point in time and

(ii) receiving a second signal of said plurality of signals from a second transmitter position at a second point in time, wherein said second point in time occurs at least 1 second after said first point in time; and

determining position of said device relative to said fixed coordinate system to a second level of accuracy based at least in part on said calibration and received plurality of signals, wherein said second level of accuracy is more accurate than said first level of accuracy,

wherein said determining step comprises;

a. determining, based on said first signal, a first range to said first transmitter position to define a first spherical surface centered at said first transmitter position;

b. determining, based on said second signal, a second range to said second transmitter position to define a second spherical surface centered at said second transmitter position;

and

c. combining said first signal and said second signal to determine said position of said device relative to said fixed coordinate system to said second level of accuracy, wherein said combining comprises determining an intersection between said first and second spherical surfaces.

2. A method as set forth in claim 1, wherein said computer network is an asynchronous network.

3. A method as set forth in claim 2, wherein said computer network uses industry standard packet communication protocols.

4. A method as set forth in claim 2, wherein said computer network is an Internet Protocol (IP) network, wherein said calibrating step comprises calibrating time and frequency references of said device to said time and frequency references of said at least one peering point server at least in part through communications over said IP network between said device and said at least one peering point servers.

5. A method as set forth in claim 4, wherein said device operates using Voice Over Internet Protocol (VoIP).

6. A method as set forth in claim 5, wherein said device is a VoIP phone.

7. A method as set forth in claim 4, wherein said computer network is the Internet.

8. A method as set forth in claim 4, wherein said computer network is an intranet.

9. A method as set forth in claim 4, wherein said computer network is a wide area network.

10. A method as set forth in claim 1, wherein said connection is a broadband connection.

11. A method as set forth in claim 10, wherein said broadband connection is operable to transfer at least 128 Kbps bi-directionally.

12. A method as set forth in claim 1, wherein said fixed coordinate system is a fixed coordinate system used by a Global Navigation Satellite Services (GNSS) system.

13. A method as set forth in claim 12, wherein said GNSS system is the GPS.

14. A method as set forth in claim 12, wherein said GNSS system is Glonass.

15. A method as set forth in claim 12, wherein said GNSS system is Galileo.

16. A method as set forth in claim 12, wherein said GNSS system is QZSS.

17. A method as set forth in claim 1, wherein said fixed coordinate system is a fixed coordinate system used by terrestrial based navigation system.

18. A method as set forth in claim 1, further comprising:

performing an IP trace route for the routing between said model server and said device; and

accessing at least one database of positions of other devices on said computer network, wherein said estimating is based at least in part on a position of another device attached to said computer network present in said IP trace route.

19. A method as set forth in claim 18, wherein at least one of said at least one database of positions was developed by gathering data from previous performances of the present method.

20. A method as set forth in claim 18, wherein at least one of said at least one database of positions of other devices is accessed by said model server through said computer network.

21. A method as set forth in claim 1, wherein said first level of accuracy is within 100 km of said determined position.

22. A method as set forth in claim 1, wherein said first level of accuracy is within 30 km of said determined position.

23. A method as set forth in claim 1, wherein said estimation is based on the known position relative to said fixed coordinate system of an apparatus connected to a router which is connected to said device.

24. A method as set forth in claim 23, wherein said first level of accuracy is within 200 meters.

25. A method as set forth in claim 1, wherein said positioning system is terrestrial based system.

26. A method as set forth in claim 1, wherein said positioning system is a GNSS system.

27. A method as set forth in claim 26, wherein said GNSS system is the GPS.

28. A method as set forth in claim 26, wherein said GNSS system is Glonass.

29. A method as set forth in claim 26, wherein said GNSS system is Galileo.

30. A method as set forth in claim 26, wherein said GNSS system is QZSS.

31. A method as set forth in claim 26, wherein said data is obtained from at least one model server attached to said computer network.

32. A method as set forth in claim 31, wherein said signal characteristics comprise estimates of one or more of the following:

signal frequency, signal code phase, frequency rate of change over time, navigation code bit state, and bit time transition.

33. A method as set forth in claim 1, wherein said positioning system is the GPS and said time and frequency references of said peering point server are calibrated to time and frequency references of said GPS at least in part by reception of signals from said GPS.

34. A method as set forth in claim 1, wherein said peering point server maintains calibration with said positioning system at least in part by an internal timing reference.

35. A method as set forth in claim 34, wherein said internal clock accuracy is greater than 100 parts per billion as measured against time reference of said positioning system.

36. A method as set forth in claim 1, further comprising the steps of:

determining local atmospheric pressure; and

calibrating a barometric altimeter located in said device based on said local atmospheric pressure.

37. A method as set forth in claim 1, further comprising the steps of:

improving said first level of accuracy based on characteristics of said communications over said computer network between said device and said at least one peering point server.

38. A method as set forth in claim 37, wherein said original first level of accuracy is poorer than 5000 meters and said improving improves said first level of accuracy to within 5000 meters.

39. A method as set forth in claim 1, wherein said calibration is between said device and a single peering point server of said at least one peering point server, wherein said calibration is facilitated by two-way communication between said single peering point server and said device.

40. A method as set forth in claim 1, wherein said calibration is between said device and a plurality of said at least one peering point server.

41. A method as set forth in claim 40, wherein said calibration is facilitated by two-way communication between said device and said plurality of said at least one peering point server.

42. A method as set forth in claim 40, wherein said calibration is facilitated by one-way communication from said device to said plurality of at least one peering point server.

43. A method as set forth in claim 1, wherein said step of receiving comprises integrating at least one of said plurality of signals over a time period greater than about 0.01 seconds.

44. A method as set forth in claim 43, wherein said step of receiving comprises integrating at least one of said plurality of signals over a time period greater than about 0.5 seconds.

45. A method as set forth in claim 1, wherein said positioning system is a GNSS system wherein said step of receiving comprises acquiring said plurality of signals over a time period of at least about 1 second, wherein signals received during any 1 second period of time during said time period of at least about 1 second are insufficient to determine a position of said device.

46. A method as set forth in claim 1, wherein said positioning system is a GNSS system wherein said step of receiving comprises acquiring said plurality of signals over a time period greater than about 1 hour, wherein signals received during any 1 hour period of time during said time period greater than about 1 hour are insufficient to determine a position of said device.

47. A method as set forth in claim 45, wherein said positioning system is a GNSS system, wherein said step of receiving comprises acquiring said plurality of signals from one satellite of said GNSS system.

48. A method as set forth in claim 1, wherein said second level of accuracy is within 50 meters.

49. A method as set forth in claim 1, wherein said determination further comprises determining position of said device relative to said fixed coordinate system to a third level of accuracy based at least in part on said calibration and received plurality of signals.

50. A method as set forth in claim 49, wherein said second level of accuracy is within 200 meters.

51. A method as set forth in claim 49, wherein said third level of accuracy is within 50 meters.

52. A method as set forth in claim 1, wherein calculations necessary to achieve said determination are performed by a module that is a part of said device.

53. A method as set forth in claim 1, wherein calculations necessary to achieve said determination are performed by a module that is not a part of said device and is connected to said computer network.

54. A method as set forth in claim 53, wherein said calculations are performed by said model server.

55. A method as set forth in claim 54, further comprising the step of:

storing said determined position in a database.

56. A method as set forth in claim 1, wherein said comprises receiving a plurality of signals from a single transmitter of said positioning system.

57. A method as set forth in claim 1, wherein said determining consists of receiving a plurality of signals from a plurality of transmitters of said positioning system.

58. A method as set forth in claim 1, wherein said method further comprises:

reporting from said device position information for said device based on said determined position.

59. A method as set forth in claim 58, wherein said reporting is over said computer network.

60. A method as set forth in claim 1, wherein said reporting comprises reporting an electronically readable device identifier and device location information for said identified device.

61. A method as set forth in claim 60, wherein said reporting is to an emergency call center.

62. A method as set forth in claim 1, wherein said device is a wireless access point.

63. A method as set forth in claim 62, wherein a wireless device in communication with said wireless access point reports its position to be that of the wireless access point.

64. A method as set forth in claim 62, wherein a wireless device in communication with said wireless access point:

determines its location relative to said wireless access point; and

determines its position relative to said fixed coordinate system based on said wireless access point position and said location relative to said wireless access point.

82. A method as set forth in claim 1, wherein said calibrating step calibrates said time reference of said device to within 120 nanoseconds of said time reference of said at least one peering point server.

83. A method as set forth in claim 1, wherein said device is a wireless access point, wherein the method further comprises:

determining a location relative to said wireless access point of a wireless device in communication with said wireless access point; and

determining a position of said wireless device relative to said fixed coordinate system based on said wireless access point position and said location relative to said wireless access point.

84. A method as set forth in claim 1, wherein said device is a VoIP phone.

85. A method as set forth in claim 1, wherein said second point in time occurs at least 1 hour after said first point in time.

86. A method as set forth in claim 4, wherein said positioning system is a GNSS system wherein said step of receiving comprises acquiring said plurality of signals over a time period of at least about 1 second, wherein signals received during any 1 second period of time during said time period of at least about 1 second are insufficient to determine a position of said device.

87. A method as set forth in claim 86, further comprising:

performing an IP trace route for the routing between said model server and said device; and

accessing at least one database of positions of other devices on said computer network, wherein said estimating is based at least in part on a position of another device attached to said computer network present in said IP trace route.

88. A method as set forth in claim 87, wherein said device is a wireless access point, wherein the method further comprises:

determining a location relative to said wireless access point of a wireless device in communication with said wireless access point; and

determining a position of said wireless device relative to said fixed coordinate system based on said wireless access point position and said location relative to said wireless access point.

89. A method as set forth in claim 87, wherein said device is a VoIP phone.

90. A method as set forth in claim 4, further comprising:

performing an IP trace route for the routing between said model server and said device;

and accessing at least one database of positions of other devices on said computer network, wherein said estimating is based at least in part on a position of another device attached to said computer network present in said IP trace route.

91. A method as set forth in claim 90, wherein said device is a wireless access point, wherein the method further comprises:

determining a location relative to said wireless access point of a wireless device in communication with said wireless access point; and

determining a position of said wireless device relative to said fixed coordinate system based on said wireless access point position and said location relative to said wireless access point.

92. A method as set forth in claim 90, wherein said device is a VoIP phone.

93. A method as set forth in claim 92, wherein said calibrating step calibrates said time reference of said VoIP phone to within 120 nanoseconds of said time reference of said at least one peering point server.

65. An apparatus comprising:

a network interface module;

a signal receiving module that receives signals transmitted by at least one transmitter of a positioning system, wherein said signal receiving module receives a first signal from a first transmitter position at a first point in time and a second signal from a second transmitter position at a second point in time, wherein said second point in time occurs at least 1 second after said first point in time;

a frequency and time aligning module for aligning said signal receiving module, wherein said frequency and time aligning module is operable to obtain frequency and time aligning information regarding said positioning system over a connection to a network via said network interface module;

a timing module, wherein said timing module is operable to calibrate a time reference of said apparatus with a time reference of said positioning system over a connection to said network via said network interface module;

and

a processing module, wherein said processing module;

(i) estimates a position of said apparatus relative to said positioning system to a first level of accuracy by communicating over said computer network;

(ii) determines, based on said first signal, a first range to said first transmitter position to define a first spherical surface centered at said first transmitter position;

(iii) determines, based on said second signal, a second range to said second transmitter position to define a second spherical surface centered at said second transmitter position;

(iv) determines an intersection between said first and second spherical surfaces; and

(v) determines a position of said apparatus relative to said positioning system to a second level of accuracy based at least in part on said calibration and a combination of said first signal and said second signal, wherein said second level of accuracy is more accurate than said first level of accuracy.

66. The apparatus of claim 65, wherein said apparatus is a voice over data network unit.

67. The apparatus of claim 65, wherein said apparatus is a VoIP unit.

68. The apparatus of claim 65, wherein said apparatus is a phone.

69. The apparatus of claim 65, wherein said network interface module is capable of interfacing with an IP network.

70. The apparatus of claim 65, wherein said positioning system is a GNSS.

71. The apparatus of claim 70, wherein said GNSS is the GPS.

72. The apparatus of claim 65, further comprising a barometric pressure sensor.

94. The apparatus of claim 65, wherein said timing module calibrates said time reference of said apparatus to within 120 nanoseconds of said time reference of said positioning system over said connection to said network.

73. A Voice Over Internet Protocol (VoIP) device comprising:

a voice conversion module that converts voice to data and data to voice;

a network interface module;

a signal receiving module that receives signals transmitted by at least one transmitter of a GNSS, wherein said signal receiving module receives a first signal from a first transmitter position at a first point in time and a second signal from a second transmitter position at a second point in time, wherein said second point in time occurs at least 1 second after said first point in time;

a frequency and time aligning module for aligning said signal receiving module, wherein said frequency and time aligning module is operable to obtain frequency and time information regarding said GNSS over a connection to a network via said network interface module;

a timing module, wherein said timing module is operable to calibrate a time reference of said apparatus with a time reference of said GNSS over a connection to said network via said network interface module; and

a processing module for processing signals received by said signal receiving module, wherein said processing module;

(i) estimates a position of said VoIP device relative to said GNSS to a first level of accuracy by communicating over said network;

(ii) determines, based on said first signal, a first range to said first transmitter position to define a first spherical surface centered at said first transmitter position;

(iii) determines, based on said second signal, a second range to said second transmitter position to define a second spherical surface centered at said second transmitter position;

(iv) determines an intersection between said first and second spherical surfaces; and

(v) determines a position of said VoIP device relative to said GNSS to a second level of accuracy based at least in part on said calibration and a combination of said first signal and said second signal, wherein said second level of accuracy is more accurate than said first level of accuracy.

74. The VoIP device of claim 73, wherein said GNSS is the GPS.

75. A system for use in determining a position of a device connected to a network relative to a fixed coordinate system, comprising:

a device connected to a network, wherein said device receives signals transmitted by at least one transmitter of a positioning system, wherein said device receives a first signal from a first transmitter position at a first point in time and a second signal from a second transmitter position at a second point in time, wherein said second point in time occurs at least 1 second after said first point in time;

a model server in communication with said device over said network, wherein said model server is operable to provide to said device information regarding signal characteristics of said transmitters of said positioning system;

a peering point server to communicate with said device over said network, wherein said peering point server is operable to calibrate over said network a time reference of said device to a time reference of said positioning system; and

a processing module for processing signals received by said device, wherein said processing module;

(i) estimates a position of said device relative to said positioning system to a first level of accuracy by communicating over said network;

(ii) determines, based on said first signal, a first range from said device to said first transmitter position to define a first spherical surface centered at said first transmitter position;

(iii) determines, based on said second signal, a second range from said device to said second transmitter position to define a second spherical surface centered at said second transmitter position;

(iv) determines an intersection between said first and second spherical surfaces; and

(v) determines a position of said device relative to said positioning system to a second level of accuracy based at least in part on said calibration and a combination of said first signal and said second signal, wherein said second level of accuracy is more accurate than said first level of accuracy.

76. The system of claim 75, wherein said positioning system is the GPS.

77. The system of claim 75, wherein said model server is operable to determine an estimate of the location of said device.

78. The system of claim 75, wherein said model server comprises a database correlating a plurality of devices to a plurality of corresponding locations.

79. The system of claim 75, wherein said device is a VoIP phone.

80. The system of claim 75, wherein said network is an asynchronous network.

81. The system of claim 80, wherein said asynchronous network is an IP network.