Multiple location estimators for wireless location

• US 8,032,153 B2
• Filed: 01/14/2008
• Issued: 10/04/2011
• Est. Priority Date: 09/09/1996
• Status: Expired due to Fees

• Current Assignee: TracBeam LLC (Dennis J. Dupray)
• Original Assignee: TracBeam LLC (Dennis J. Dupray)
• Inventors: Dupray, Dennis J., Karr, Charles L.
• Primary Examiner(s): Kincaid; Lester
• Assistant Examiner(s): Jama; Isaak R
• Application Number:
  US12/014,092
• Publication Number:
  US 20080113672A1
• Time in Patent Office: 1,359 Days
• Field of Search: 455/456.1
• US Class Current: 455/456.1
• CPC Class Codes: G01S 1/026 of associated receivers
• CPC Class Codes: G01S 1/028 Simulation means, e.g. of beacon signals therefor for teaching or training purposes G09B9/00
• 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 5/0054 of actual mobile position, i.e. position calculation on base station
• CPC Class Codes: G01S 5/021 Calibration, monitoring or correction G01S5/0252 takes precedence
• CPC Class Codes: G01S 5/0244 Accuracy or reliability of position solution or of measurements contributing thereto
• CPC Class Codes: G01S 5/0257 Hybrid positioning by coordinating position lines of different shape G01S5/12
• CPC Class Codes: G01S 5/0278 involving statistical or probabilistic considerations G01S5/0252, G01S5/0294 take precedence
• CPC Class Codes: G01S 5/06 Position of source determined by co-ordinating a plurality of position lines defined by path-difference measurements G01S5/12 takes precedence
• CPC Class Codes: H04W 4/025 using location based information parameters
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management

Abstract

A wireless location system is disclosed that may be configured as a gateway for receiving a plurality of requests for locating mobile stations for, e.g., E911 requests, vehicle location or tracking. For each mobile station (MS) location request, the system: (a) activates one or more location estimators for locating the MS, (b) receives one or more MS location estimates from the estimators, and (c) transmits a resulting location estimate(s) to an identified destination. MS locations are determined using one or more locating technologies based on, e.g.: computed offsets from terrestrial base stations, satellite transmissions, indoor antennas, low range base stations, and/or signal fingerprinting. The system may: adapt with environmental changes, evaluate MS locations using heuristics/constraints, and/or adjust MS estimates for more reliable and accurate estimates. The system is useful for 911 emergencies, tracking, routing (e.g., to desired products/services), people and animal location including applications for confinement to and exclusion from certain areas.

Claims

1. A method for locating, from a plurality of wireless mobile stations, one of the wireless mobile stations using measurements of wireless signals, wherein at least one of:

(i) said measurements and (ii) said wireless signals are transmitted between said one wireless mobile station and at least one of a plurality of fixed location communication stations, each communication station capable of at least one of receiving wireless signals from, and transmitting wireless signals to said one wireless mobile station, comprising the following steps at A and B which are performed by computational machinery;

(A) receiving, from each of at least first and second mobile station location estimators, corresponding first and second information related to likely geographical approximations for a location of said one wireless mobile station, wherein (a) and (b) following are satisfied;

(a) for determining a likely geographical approximation, GA_A, for a location, L_A, of a second of the wireless mobile stations at a time T_A, said first mobile station location estimator generates GA_A without requiring a prior likely geographical location approximation generated by said second mobile station location estimator for locating the second wireless mobile station at substantially the location L_A at substantially the time T_A, and,

(b) for estimating a likely geographical approximation, GA_B, for a location, L_B, of a third one of the wireless mobile stations at a time T_B, said second mobile station location estimator generates GA_B without requiring a prior likely geographical location approximation generated by said first mobile station location estimator for locating the third wireless mobile station at the location L_B at substantially the time T_B;

(B) determining a resulting location estimate of said one wireless mobile station, wherein said step of determining includes at least one of the substeps (B1) through (B2) following;

(B1) when said first and second information include, respectively, first and second likely geographical approximations, combining said first and second likely geographical approximations so that said resulting location estimate is dependent on each of said first and second location likely geographical approximations; and

(B2) selecting one of said first and second information for receiving preference in determining said resulting location estimate, wherein said selecting is dependent upon location related data in at least one of said first and second information.

2. The method of claim 1, further including a step of providing display information for:

(a) displaying a representation of said resulting location estimate, wherein said display information is for displaying with a map of an area having the resulting location estimate, and (b) at a same time displaying information indicative of an accuracy of the resulting location estimate.

3. The method of claim 1, wherein the first and second mobile station location estimators comprise hardware and software that perform different location determining computational techniques for locating the one wireless mobile station.

4. The method of claim 3, wherein for an unknown location L, of the one wireless mobile station M, from which location related data is obtained for locating M, wherein the location related data is obtained from values of one or more wireless signal characteristics, the values dependent upon signal transmission of wireless signals to or from the one mobile station M:

for estimating the location L from the location related data at least one of (1) and (2) hold;

(1) a first collection of location determining computational machinery instructions is performed by an activation of the first mobile station location estimator, the first collection being an operational representation of a first location determining technique;

wherein the first location technique;

(i) is representable independently of all actual geographical locations, and (ii) identifies, for use in determining each unknown mobile station location (U₁) of a plurality of unknown mobile station locations, a first predetermined set of at least one of the wireless signal characteristics whose values are dependent upon signal transmission of wireless signals to or from the one unknown mobile station location U₁;

wherein the performance of the first collection determines a first location estimate of L, wherein an operational representation of the first location determining technique is not performed by the second mobile station location estimator for determining a location estimation of L, or

(2) a second collection of location determining computational machinery instructions is performed by an activation of the second mobile station location estimator, the second collection being an operational representation of a second location determining technique;

wherein the second location determining technique;

(i) is representable independently of all actual geographical locations, and (ii) identifies, for use in determining each unknown mobile station location (U₂) of a plurality of unknown mobile station locations, a second predetermined set of at least one of the wireless signal characteristics whose values are dependent upon signal transmission of wireless signals to or from the one unknown mobile station location U₂;

wherein the performance of the second collection determines a second location estimate of L, wherein an operational representation of the second location determining technique is not performed by the first mobile station location estimator for determining a location estimation of L.

5. The method of claim 4, wherein the one or more wireless signal characteristics for locating an unknown mobile location includes at least one of:

a time of arrival of a wireless signal transmitted from the unknown mobile location to one of the communication stations attached to the Earth, a time of arrival of a wireless signal transmitted to the unknown mobile location from a satellite, and a signal strength of a wireless signal transmitted from the unknown mobile location to one of the communication stations attached to the Earth.

6. The method of claim 3, wherein for locating the one wireless mobile station, M herein, the first and second mobile station location estimators perform different location determining computational techniques for locating M such that if, for each of the first and second mobile station location estimators, identical data were available for providing all input for locating M, then upon activating each of the first and second location estimators with their input for locating M obtained from the identical data, (1) a location related computation is performed by the activation of the first mobile station location estimator that is not performed by the activation of the second location estimator, or, (2) a location related computation is performed by the activation of the second mobile station location estimator that is not performed by the activation of the first location estimator.

7. The method of claim 1, wherein the first mobile station location estimator determines the first information via a computational machinery implementation of a first location determining technique such that for data, obtained from values of first predetermined wireless transmission characteristics of wireless signal communication with the one mobile station, being available as input to the first mobile station location estimator, the first mobile station location estimator outputs a likely geographical approximation of the one mobile station, the likely geographical approximation being the first likely geographical approximation when (B1) of claim 1 holds;

wherein the second mobile station location estimator determines the second information via a computational machinery implementation of a second location determining technique such that for data, obtained from values of second predetermined wireless transmission characteristics of wireless signal communication with the one mobile station, being available as input to the second mobile station location estimator, the second mobile station location estimator outputs a second likely geographical approximation of the one mobile station, the likely geographical approximation being the second likely geographical approximation when (B1) of claim 1 holds;

wherein at least one of;

(1) a computational machinery implementation of the second location determining technique is not performed by the first mobile station location estimator in determining the first information, or (2) a computational machinery implementation of the first location determining technique is not performed by the second mobile station location estimator in determining the second information.

8. The method of claim 7 wherein for each wireless mobile station (N) of the wireless mobile stations, N is an instance of the one wireless mobile station.

9. The method of claim 7, wherein for each wireless mobile station (N) of a multiplicity of the wireless mobile stations, wherein N is the instance of the one wireless mobile station, the substep B1 is performed.

10. The method of claim 4, wherein for each wireless mobile station (N) of a multiplicity of the wireless mobile stations, wherein N is the instance of the one wireless mobile station, the substep B1 is performed.

11. The method of claim 3, wherein for each wireless mobile station (N) of a multiplicity of the wireless mobile stations, wherein N is the instance of the one wireless mobile station, the substep B1 is performed.

12. The method of claim 3, wherein for each wireless mobile station (M) of a multiplicity of the wireless mobile stations, wherein M is the instance of the one wireless mobile station, the substep B2 is performed.

13. The method of claim 4, wherein for each wireless mobile station (M) of a multiplicity of the wireless mobile stations, wherein M is the instance of the one wireless mobile station, the substep B2 is performed.

14. The method of claim 7, wherein for each wireless mobile station (M) of a multiplicity of the wireless mobile stations, wherein M is the instance of the one wireless mobile station, the substep B2 is performed.

15. The method of claim 1, wherein the first mobile station location estimator is a collection of one or more computational machinery modules that include, or are operationally dependent upon, a signal processing technique, provided by computational machinery, the first mobile station location estimator for estimating a location of the one wireless mobile station when computational machinery for the signal processing technique is supplied with data obtained from wireless signals (S) received by the one mobile station from one or more transmitting stations not attached to the Earth, wherein said wireless signals S provide time values, and the computational machinery for the signal processing technique uses at least one differential between a time of transmission and a time of arrival for the wireless signals S transmitted by a plurality of the transmitting stations;

wherein the first information is dependent upon an output from the signal processing technique.

16. The method of claim 15, wherein the second mobile station location estimator is dependent upon a time difference of arrival of a wireless signal between the one wireless mobile station and at least one of the communication stations.

17. The method of claim 15, wherein the second mobile station location estimator is dependent upon a pattern recognition location technique, performed by computational machinery, for estimating a location of the one wireless mobile station by recognizing a pattern of characteristics of wireless signals communicated between the one wireless mobile station and one or more of the communication stations.

18. The method of claim 17, wherein the pattern recognition location technique uses characteristics of wireless signals from at least first and second wireless transmission paths of wireless transmissions between the one wireless mobile station and at least one of the communication stations.

19. The method of claim 15, wherein the second mobile station location estimator is dependent upon a direction of arrival technique, performed by computational machinery, wherein the direction of arrival technique determines a geographic estimation for a location of the one wireless mobile station by using a direction from which wireless signals arrive at one of the communication stations from the one wireless mobile station.

20. The method of claim 15, wherein the second mobile station location estimator is dependent upon location data indicative of a coverage area of at least one of the communication stations, wherein the location data is used as a location estimate for the second information.

21. The method of claim 15, wherein when the first location information is unavailable at a location, L, for the one wireless mobile station, the location estimate for the second information is used for determining the resulting location estimate.

22. The method as claimed in claim 1, further including a step of transmitting, through a telecommunications network, the first mobile station location estimator from a source site to an activation site for generating the first information;

wherein the step of transmitting includes transmitting a representation of programmatic instructions for the first mobile station location estimator via a communications network.

23. The method as claimed in claim 1, further including, for a geographical indication, GI, of one of the first and second information, a step of obtaining data indicative of a correctness that the at least one geographical indication GI represents a location that includes the one wireless mobile station.

24. The method of claim 23, wherein the data indicative of a correctness is obtained using previously obtained geographical indications for locating one or more mobile station locations.

25. The method of claim 23, wherein in performing the step B1 of combining, the data indicative of a correctness is used in determining an importance of the one of the first and second information in the resulting location estimate.

26. The method of claim 23, wherein in performing the step of selecting, the data indicative of a correctness is used in determining an importance of the one of the first and second information in the resulting location estimate.

27. The method of claim 1, wherein the first and second mobile station location estimators use different wireless signal location related data for determining the resulting location estimate.

28. The method of claim 27, wherein for determining the resulting location estimate:

(A) the first mobile station location estimator uses data indicative of a time difference between;

(1) a time of a wireless signal transmission from a transmitting station not attached to the Earth, and (2) a time of arrival of the wireless signal;

(B) the second mobile station location estimator does not use the data indicative of the time difference; and

(C) each of the first and second information includes a location estimate of the one wireless mobile station.

29. The method of claim 27, wherein for determining the resulting location estimate:

(A) the first mobile station location estimator uses data indicative of a time difference of arrival of wireless signal communications between;

(1) the one wireless mobile station, and (2) a plurality of the communication stations attached to the Earth;

(B) the second mobile station location estimator does not use the data indicative of the time difference of arrival, and

(C) each of the first and second information includes a location estimate of the one wireless mobile station.

30. The method of claim 27, wherein for determining the resulting location estimate:

(A) the first mobile station location estimator uses data indicative of a time of arrival of wireless signal communications between;

(1) one of the communication stations, and (2) the one wireless mobile station;

(B) the second mobile station location estimator does not use the data indicative of the time of arrival, and

(C) each of the first and second information includes a location estimate of the one wireless mobile station.

31. The method of claim 27, wherein for determining the resulting location estimate:

(A) the first mobile station location estimator uses data indicative of a signal strength of wireless signal communications between;

(1) one of the communication stations, and (2) the one wireless mobile station;

(B) the second mobile station location estimator does not use the data indicative of the signal strength, and

(C) each of the first and second information includes a location estimate of the one wireless mobile station.

32. The method of claim 3, further including a step of outputting display information for, at a same time:

(1) displaying a representation of a location estimate, LE, of the one first mobile station obtained from the resulting location estimate, and, (2) displaying information indicating one of;

(i) an accuracy of the location estimate LE, and (ii) a confidence or reliability in the location estimate LE.

33. The method of claim 32, wherein the display information is displayed on a map of an area having the location estimate LE, and displayed at a same time therewith is the information indicative of the accuracy of the location estimate.

34. The method of claim 5, wherein said first information is selected over said second information unless there is information indicating a likelihood of the first information providing reduced performance in locating the one wireless mobile station, wherein the first information is dependent upon a signal processing technique, performed by computational machinery, for estimating a location of the one wireless mobile station when the signal processing technique is supplied with data obtained from wireless signals S received by the one wireless mobile station from one or more transmitting stations not attached to the Earth, wherein the wireless signals S provide time values, and the signal processing technique uses at least one differential between a time of transmission and a time of arrival for the wireless signals S transmitted by a plurality of the transmitting stations.

35. The method of claim 3, further including the steps:

for the first mobile station location estimator, a step of determining the first information for locating the one wireless mobile station, wherein the first information includes one or more location estimates of a geographical location L of the one wireless mobile station, and wherein for determining at least one of the location estimates, there is (A1)-(A4) following;

(A1) a non-transient data storage of a collection, C, of wireless location related data based upon;

a plurality of data collections, wherein, for each geographical location, G, of a plurality of geographical locations, there is one of the data collections having (i) and (ii) following;

(i) a representation of the geographical location G, and

(ii) wireless signal transmission information for a wireless signal, WS, transmitted from one of;

one of the mobile stations, M, and at least one of the communication stations and received by the other of the mobile station M or the at least one communication station, wherein the wireless signal transmission information includes effects from one or more objects along a wireless transmission path of the wireless signal WS when the objects affect the wireless signal prior to being received, and wherein the mobile station M is approximately at the geographical location G; and

(A2) for first wireless signal data indicative of a wireless communication between the one wireless mobile station and a first of the communication stations, there is an identification of the first communication station for accessing a first subcollection of the collection, C, of wireless location related data, and, for second wireless signal data indicative of a wireless communication between the one wireless mobile station and a second of the communication stations, there is an identification of the second communication station for accessing a second subcollection of the collection, C, of wireless location related data;

(A3) a first value indicative of a discrepancy between wireless signal values for the first wireless signal data and the first subcollection of wireless location related data;

(A4) a second value indicative of a discrepancy between wireless signal values for the second wireless signal data and the second subcollection of wireless location related data; and

the step of determining the first information further including determining the at least one location estimate dependent upon the first and second values.

36. The method of claim 35, further including for the at least one location estimate, a step of determining a confidence therefor, wherein the confidence is indicative of a likelihood of the one wireless mobile station having an actual location represented by the at least one location estimate.

37. The method of claim 35, further including obtaining wireless signal strengths for the one wireless mobile station wirelessly communicating with the communication stations, wherein each of the first and second values are dependent upon data for at least some of the wireless signal strengths.

38. The method of claim 35, wherein the step of determining the first information includes a step of interpolating data (D) from the first subcollection, wherein the data D is used to determine the discrepancy in obtaining the first value collection C.

39. The method of claim 35, further including a step of determining one or more intermediate location estimates of the one wireless mobile station, wherein at least one of the intermediate location estimates is adjusted according to at least one environmental characteristic.

40. The method of claim 36, wherein the resulting location estimate includes data indicative of the confidence, and further including a step of providing the resulting location estimate for presentation on a computational machine display, the display presenting a wireless coverage area, wherein colors are provided on the display such that for portions of the coverage area whose corresponding representations are displayed in different ones of the colors, each different color represents a different corresponding likelihood of the one wireless mobile station being located in the portion of the coverage area represented by the color.

41. The method of claim 35, further including a step of selecting the first communication station by the computational machinery.

42. The method of claim 35, further including a step of obtaining, from wireless signal detection equipment, wireless signal location related data from at least some of the communication stations for performing a step of calibrating of one or more wireless location models that perform location estimations of the mobile stations, the calibration performed by the computational machinery.

43. An apparatus for locating, from a plurality of wireless mobile stations, one of the wireless mobile stations using measurements of wireless signals, wherein at least one of:

(i) said measurements and (ii) said wireless signals are transmitted between said one wireless mobile station and at least one of a plurality of fixed location communication stations, each communication station capable of at least one of;

receiving wireless signals from, and transmitting wireless signals to, said one wireless mobile station, comprising;

first and second mobile station location estimators provided by computational machinery;

wherein the apparatus is operative to accomplish (A) and (B) following;

(A) receive, from each of at least first and second mobile station location estimators, corresponding first and second information related to likely geographical approximations for a location of said one wireless mobile station, wherein (a) and (b) following are satisfied;

(a) for determining a likely geographical approximation, GA_A, for a location, L_A, of a second of the mobile stations at a time T_A, said first mobile station location estimator generates GA_A without requiring a prior likely geographical location approximation generated by said second mobile station location estimator for locating the second mobile station at substantially the location L_A at substantially the time T_A, and,

(b) for estimating a likely geographical approximation, GA_B, for a location, L_B, of a third one of the mobile stations at a time T_B, said second mobile station location estimator generates GA_B without requiring a prior likely geographical location approximation generated by said first mobile station location estimator for locating the third mobile station at the location L_B at substantially the time T_B;

(B) determine a resulting location estimate of said one wireless mobile station, wherein said step of determining includes at least one of the substeps (B1) through (B2) following;

(B1) when said first and second information include, respectively, first and second likely geographical approximations, combining said first and second likely geographical approximations so that said resulting location estimate is dependent on each of said first and second likely geographical approximations; and

(B2) selecting one of said first and second information for receiving preference in determining said resulting location estimate, wherein said selecting is dependent upon location related data in at least one of said first and second information.

44. The apparatus of claim 43, wherein the first mobile station location estimator is a collection of one or more computational machinery modules that include, or are operationally dependent upon, a signal processing technique, provided by computational machinery, the first mobile station location estimator for estimating a location of the one wireless mobile station when computational machinery for the signal processing technique is supplied with data obtained from wireless signals (S) received by the one mobile station from one or more transmitting stations not attached to the Earth, wherein said wireless signals S provide time values, and the computational machinery for the signal processing technique uses at least one differential between a time of transmission and a time of arrival for the wireless signals S transmitted by a plurality of the transmitting stations;

wherein the first information is dependent upon an output from the signal processing technique.