Locating system and method

• US 20070037587A1
• Filed: 05/03/2006
• Published: 02/15/2007
• Est. Priority Date: 07/14/2000
• Status: Active Grant

• Current Assignee: NorBelle LLC
• Original Assignee: NorBelle LLC
• Inventors: Keegan, Richard, Mohi, Norman, Hume, James, Scislowski, Mark, Judge, Kevin, Olivier, Robert
• Granted Patent: US 8,195,200 B2
• Time in Patent Office: Days
• US Class Current: 455/456.500
• CPC Class Codes: G01C 21/20 Instruments for performing navigational calculations G01C21/24, G01C21/26 take precedence
• CPC Class Codes: G01S 19/16 Anti-theft; Abduction
• CPC Class Codes: G01S 19/25 involving aiding data received from a cooperating element, e.g. assisted GPS
• CPC Class Codes: G01S 19/42 Determining position
• CPC Class Codes: G01S 19/48 by combining or switching between position solutions derived from the satellite radio beacon positioning system and position solutions derived from a further system
• CPC Class Codes: G01S 19/51 Relative positioning
• CPC Class Codes: G01S 19/54 using carrier phase measurements; using long or short baseline interferometry
• CPC Class Codes: G01S 2205/006 for emergency situations
• CPC Class Codes: G01S 2205/008 using a mobile telephone network
• CPC Class Codes: G01S 5/0009 Transmission of position information to remote stations involving assistance data G01S5/0236
• CPC Class Codes: G01S 5/0018 Transmission from mobile station to base station
• CPC Class Codes: G01S 5/0027 of actual mobile position, i.e. position determined on mobile
• CPC Class Codes: G01S 5/0072 Transmission between mobile stations, e.g. anti-collision systems
• CPC Class Codes: G08G 1/205 Indicating the location of the monitored vehicles as destination, e.g. accidents, stolen, rental
• CPC Class Codes: H04W 4/02 Services making use of location information
• CPC Class Codes: H04W 4/024 Guidance services

Abstract

A mobile rover has a navigation receiver receiving radio positioning data from radio positioning entities. The mobile rover can report its position to a mobile controller unit or another entity so that the location of the mobile unit can be tracked based on the radio positioning data received by the mobile rover. The radio positioning data can be processed by processing systems within the mobile rover, mobile controller, or other entities such as a position determination entity or a position determination entity proxy. The processing systems can also perform calculations to augment the radio positioning data to provide more accurate estimates of the position of the mobile controller and/or the mobile rover. The mobile controller and/or the mobile rover may be cellular telephones within a cellular network.

Claims

1. A method for determining navigation data for a location subject having at least one location data receiver using location measurement data provided by one or more location measurement data sources of a location technology source, the method comprising:

(a) establishing a location for the location subject;

(b) calculating one or more theoretical ranges from the location subject to the one or more location measurement data sources based on the location of the location subject;

(c) obtaining location measurement data via a location receiver of the location subject from the one or more location measurement data sources;

(d) calculating one or more augmented ranges from the one or more theoretical ranges and a percentage of a difference between the theoretical ranges and one or more range related parameters contained in the location measurement data;

(e) establishing an updated location of the location subject based on the augmented ranges; and

(f) repeating steps (b) through (e) while decreasing the percentage of the difference between the one or more theoretical ranges and the one or more range related parameters until a defined minimum percentage is reached.

2. The method according to claim 1, further comprising:

checking if any component of a difference between at least one range related parameter and at least one augmented range is greater than a defined threshold value; and

eliminating that range related parameter from the augmented ranges calculation if any component of that range related parameter is greater than the defined threshold.

3. The method according to claim 1, wherein a range residual is calculated for each location measurement source providing location measurement data to the location subject and the method further comprises:

determining a mean range residual and a population standard deviation for range related parameters obtained from all location measurement data sources;

low pass filtering the population standard deviation;

identifying a location measurement data source having a largest difference between its range residual and the mean range residual; and

comparing the largest difference with a defined maximum threshold and eliminating location measurement data from the identified location measurement data source from calculations.

4. The method according to claim 1, wherein the location subject comprises a controller unit tracking a rover unit.

5. The method according to claim 1, wherein the location subject comprises a rover unit being tracked by a controller unit.

6. The method according to claim 1, wherein a first location subject comprises a controller unit and a second location subject comprises a rover unit and the method further comprises:

determining an updated location for the controller unit based on the augmented ranges;

determining an updated location for the rover unit based on augmented ranges;

determining a bearing to the rover unit relative to the heading and position of the controller unit; and

upon selection by a user, displaying on a map on a display of the controller unit a bearing line to the rover unit relative to the heading and position of the controller unit or displaying absolute map positions of the controller unit and the rover unit.

7. The method according to claim 1, wherein the location measurement data sources comprise satellites in a satellite-based positioning system and the one or more range related parameters comprise pseudorange measurements.

8. The method according to claim 7, wherein the satellite-based positioning system comprises the Global Positioning System.

9. The method according to claim 1, wherein the at least one location subject comprises at least two location subjects, wherein one location subject is a controller and another location subject is a rover and the method further comprises:

determining an extent of commonality between location measurement data sources providing location measurement data to the controller and to the rover;

if the extent of commonality is greater than a specified value, calculating absolute navigation data for the controller and calculating relative navigation data for the rover relative to the controller; and

if the extent of commonality is less than a specified value, calculating absolute navigation data for the controller and calculating absolute navigation data for the rover.

10. The method according to claim 9, wherein the controller has a display and the method further comprises displaying a bearing line from the controller to the rover relative to the heading and position of the controller.

11. A computer-readable medium having computer-executable instructions for performing the method according to claim 1.

12. The method according to claim 1, wherein the location subject comprises a cellular telephone having a receiver enabled to receive signals from satellite-based location technology sources and/or land based location technology sources, whereby the method improves the accuracy of a determined location for the cellular telephone.

13. The method according to claim 12, wherein the step of establishing a location for the location subject comprises establishing the location based on receiving information from a cellular network.

14. The method according to claim 1 wherein the one or more location measurement data sources comprise selected GPS satellites.

15. A system for locating and tracking one or more mobile units, wherein the system is operable with a wireless communication network, and the system comprises:

one or more mobile units, wherein at least one mobile unit comprises;

a wireless communication module enabled to transmit and receive navigation messages via the wireless communication network; and

a first location data receiver, wherein the first location receiver obtains location data from a plurality of location measurement data sources of a location technology source; and

at least one position processing system, wherein the at least one position processing system receives location measurement data from the first location receiver and calculates a location of the at least one mobile unit based on range calculations to the location measurement data sources based on an established location obtained from computing differences between theoretical ranges to the location measurement data sources and measured ranges to the location measurement data sources.

16. The system according to claim 15, wherein the at least one position processing system does not base the range calculations on range data for a location measurement data source when any direction cosine for a difference between a pseudorange and a calculated range is greater than a defined threshold value.

17. The system according to claim 15, wherein the at least one position processing system discards the range calculations based on range data for a location measurement data source when a difference between a range residual for data obtained from that location measurement data source and a mean range residual for data obtained from all location measurement data sources is greater than a defined threshold.

18. The system according to claim 15, wherein the system has at least one mobile unit comprising a controller unit and one or more mobile units comprising rover units.

19. The system according to claim 18, wherein the controller unit includes the at least one position processing system.

20. The system according to claim 18, wherein the rover units each include position processing systems.

21. The system according to claim 15, further comprising an applications server, wherein the applications server comprises the at least one position processing system.

22. The system according to claim 21, wherein the applications server performs calculations based on relative positions between the controller unit and at least one rover unit.

23. The system according to claim 21, wherein the applications server performs calculations based absolute positions of the controller unit and at least one rover unit.

24. The system according to claim 18, wherein navigation information is sent from the controller unit to at least one rover unit and/or navigation information is sent from at least one rover unit to the controller unit

25. The system according to claim 18, wherein the controller unit has a display and the display shows a bearing line to at least one rover unit from the controller unit relative to the heading and position of the controller unit.

26. The system according to claim 23, wherein the controller unit has a display and the display shows a bearing line to at least one rover unit from the controller unit relative to the heading and position of the controller unit.

27. The system according to claim 15, further comprising a computer executing a web browser program, and the web browser program has a display showing a location of at least one mobile unit on a map.

28. The system according to claim 15, wherein at least one mobile unit comprises a cellular telephone communicating with a cellular network, whereby the at least one position processing system improves the accuracy of a determined location for the cellular telephone.

29. The system according to claim 15, wherein the plurality of location measurement data sources comprise selected GPS satellites.

30. A method for calculating navigation data for one or more location subjects, the method comprising:

obtaining location measurement data at the one or more location subjects from a plurality of location measurement data sources of a location technology source;

generating augmented location measurements by one or more of the following three steps;

normalizing the location measurement data to maintain a consistent initial condition for a measurement set,

smoothing the location measurement data, and

eliminating any location measurement data outside specified limits;

time aligning all augmented location measurements;

determining expected position values based on time aligned location measurements;

filtering the expected position values and time aligned location measurements to provide calculated navigation data for the one or more location subjects.

31. The method according to claim 30, wherein the method further comprises weighting the time aligned location measurements before filtering the expected position values and time aligned location measurements.

32. The method according to claim 30, wherein the method further comprises:

obtaining compass measurements for the one or more location subjects from one or more compasses;

generating improved compass measurements by one or more of the following two steps;

averaging the compass measurements; and

eliminating any compass measurements outside specified limits;

time aligning the improved compass measurements with the time aligned location measurements;

determining expected position values based on the time aligned compass measurements; and

wherein filtering the expected position values and time aligned location measurements comprises filtering the expected position values, the time aligned location measurements and the time aligned compass measurements to provide calculated navigation data for the one or more location subjects.

33. The method according to claim 32, wherein the method further comprises weighting the time aligned location measurements and the time aligned compass measurements before filtering the expected position values and time aligned location measurements.

34. The method according to claim 30 wherein the one or more location subjects comprise a controller and at least one rover unit and the method further comprises:

determining an extent of commonality between location measurement data sources providing location measurement data to the controller and to the at least one rover;

if the extent of commonality is greater than a specified value, calculating absolute navigation data for the controller and calculating relative navigation data for the at least one rover relative to the controller; and

if the extent of commonality is less than a specified value, calculating absolute navigation data for the controller and calculating absolute navigation data for the at least one rover.

35. The method according to claim 34, wherein the controller has a display and the method further comprises displaying a bearing line from the controller to the at least one rover on the display relative to the heading and position of the controller.

36. The method according to claim 30, wherein the method further comprises displaying a location of at least one location subject on a map shown on a cellular telephone display and/or a map shown on a web browser screen.

37. A computer-readable medium having computer-executable instructions for performing the method according to claim 30.

38. The method according to claim 30, wherein at least one location subject comprises a cellular telephone having a receiver enabled to receive signals from satellite-based location measurement data sources and/or land based location measurement data sources.

39. The method according to claim 30, wherein at least one location subject comprises a cellular telephone communicating with a cellular network, whereby the method improves the accuracy of a determined location for the cellular telephone.

40. The method according to claim 30, where the plurality of location measurement data sources comprise selected GPS satellites.

41. A system for locating and tracking one or more mobile units, wherein the system is operable with a wireless communication network, and the system comprises:

one or more mobile units, wherein at least one mobile unit comprises;

a wireless communication module enabled to transmit and receive navigation messages via the wireless communication network; and

one or more location data receivers, wherein the one or more location data receivers obtain location measurement data from a plurality of location measurement data sources of at least one location technology source; and

at least one position processing system, wherein the at least one position processing system receives the location measurements, performs calculations to augment the location measurements, determines expected position values, and calculates navigation data for the at least one mobile unit based on the expected position values.

42. The system according to claim 41, wherein the at least one position processing system weights the expected position values before calculating the navigation data.

43. The system according to claim 41, wherein the at least one mobile unit further comprises one or more compasses providing compass measurements, and the at least one position processing system receives the compass measurements, performs calculations to improve the compass measurements, and calculates the navigation data based on the expected position values and the improved compass measurements.

44. The system according to claim 43, wherein the at least one position processing system weights the location measurements and the improved compass measurements before calculating the navigation data.

45. The system according to claim 41, wherein the one or more mobile units comprise a controller unit and at least one rover unit and the at least one position processing system determines an extent of commonality between location measurement data sources providing location measurement data to the controller and to the at least one rover and the at least one position processing system calculates relative navigation data for the at least one rover unit or absolute navigation data for the at least one rover unit based on the extent of commonality.

46. The system according to claim 45, wherein the controller has a display and the display shows a bearing line from the controller to the at least one rover unit relative to the heading and position of the controller.

47. The system according to claim 41, further comprising a computer executing a web browser program, and the web browser program has a display showing the location of at least one mobile unit on a map.

48. The system according to claim 41, wherein at least one mobile unit has a display and the display shows the location of at least one other mobile unit on a map.

49. The system according to claim 41, wherein the plurality of location measurement data sources comprises selected GPS satellites,

50. A method for providing improved pseudorange values to a location subject using pseudorange data provided by a plurality of location measurement data sources of a location technology source, the method comprising steps of:

(a) obtaining pseudorange data at the location subject from each location measurement data source;

(b) establishing a position for the location subject;

(c) determining a theoretical range between the position of the location subject and each location measurement data source;

(c) calculating a plurality of range residuals, each range residual being calculated for each location measurement data source based on a difference between the theoretical range to the location measurement data source and the pseudorange data obtained from the location measurement data source;

(d) calculating a residual mean and a residual sigma for the plurality of range residuals;

(e) establish a threshold value based on the residual sigma;

(f) determine if a difference between the range residual for any one location measurement data source and the residual mean is greater than the threshold;

(g) if there is no difference greater than the threshold, calculate an improved pseudorange value for each location measurement data source by subtracting the residual mean from the pseudorange data obtained from that location measurement data source;

(h) if there is a difference greater than the threshold, determine if valid pseudorange data has been obtained from enough location measurement data sources to establish a position;

(i) if valid pseudorange data has been obtained from enough location measurement data sources, calculate an improved pseudorange value for each location measurement data source that has a difference less than or equal the threshold by subtracting the residual mean from the pseudorange data obtained from that location measurement data source; and

(j) if valid pseudorange data has not been obtained from enough location measurement data sources;

add a low pass filtered residual sigma to the residual sigma and repeat steps (a) through (j)

51. A computer-readable medium having computer-executable instructions for performing the method according to claim 50.

52. The method according to claim 50, wherein the location subject comprises a cellular telephone communicating with a cellular network, whereby the method improves a determined location for the cellular telephone.

53. In a wireless communication system having at least one mobile unit operable with a wireless communication network with the at least one mobile unit having a location data receiver operable to receive location data from a plurality of location measurement data sources of a location technology source, a subsystem comprising:

at least one position processing system, wherein the at least one position processing system receives location measurement data from the location data receiver and calculates a location of the at least one mobile unit based on range calculations to the location measurement data sources based on an established location obtained from computing differences between theoretical ranges to the location measurement data sources and measured ranges to the location measurement data sources.

54. The subsystem according to claim 53, wherein the at least one position processing system does not base the range calculations on range data for a location measurement data source when any component of a difference between a measured range and a calculated range is greater than a defined value for that location measurement data source.

55. The subsystem according to claim 53, wherein the at least one position processing system discards the range calculations based on range data for a location measurement data source when a difference between a range residual for data obtained from that location measurement data source and a mean range residual for data obtained from all location measurement data sources is greater than a defined threshold.

56. The subsystem according to claim 53, wherein the wireless communication system has at least one mobile unit comprising a controller unit and one or more mobile units comprising rover units.

57. The subsystem according to claim 56, wherein a present controller heading of the controller unit is calculated and controller position data, the present controller heading, and a rover position is calculated to display a bearing line to at least one rover unit relative to the controller unit heading and position on a controller display, and wherein the present controller heading is compared to one or more previous controller headings to determine if the present controller heading is valid.

58. The subsystem according to claim 57, wherein a heading angular difference value is calculated based on the present controller heading and previous controller headings and the present controller heading is determined to be valid if the absolute value of the heading angular difference value is less than a first angular threshold.

59. The subsystem according to claim 57, wherein a plurality of heading angular difference values are calculated on the present controller heading and previous controller headings and the heading angular difference values are compared to defined angular thresholds to determine if the present controller heading is valid and to determine the quality of the present controller heading.

60. The subsystem according to claim 56, wherein a user establishes a geographic zone for at least one rover unit and calculations are performed to determine whether the at least one rover unit is inside the geographic zone or outside the geographic zone.

61. The subsystem according to claim 53, wherein the wireless communication system has a plurality of mobile units and has a position determination entity for assisting in location determination for the mobile units where the position determination entity receives navigation messages either directly or indirectly from the mobile units and sends navigation messages either directly or indirectly to the mobile units or other entities, and the subsystem further comprises:

a position determination entity proxy operable to receive navigation messages sent from at least one mobile unit and/or operable to receive navigation messages sent from the position determination entity.

62. The subsystem according to claim 61, wherein the position determination entity proxy extracts and saves some or all information from navigation messages sent from the at least one mobile unit to the position determination entity and forwards the navigation messages to the position determination entity and/or extracts some or all information from navigation messages sent from the position determination entity to the at least one mobile unit and forwards the navigation messages to the at least one mobile unit.