WIRELESS LOCATION USING LOCATION ESTIMATORS

• US 20130281115A1
• Filed: 03/15/2013
• Published: 10/24/2013
• Est. Priority Date: 09/09/1996
• Status: Active Grant

• Current Assignee: TracBeam LLC (Dennis J. Dupray)
• Original Assignee: TracBeam LLC (Dennis J. Dupray)
• Inventors: Dupray, Dennis J., Karr, Charles L.
• Granted Patent: US 9,277,525 B2
• Time in Patent Office: Days
• 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 including one or more location centers for outputting locations of mobile stations (MS) for both local and global MS location requests via Internet communication between a distributed network of location centers. The system uses a plurality of MS locating technologies including those based on: two-way TOA and TDOA; pattern recognition; distributed antenna provisioning; GPS signals. Difficulties, such as multipath, poor location accuracy and poor coverage are alleviated via such technologies in combination with: (a) adapting and calibrating system performance according to environmental and geographical changes; (b) capturing location signal data for continual enhancement of an historical database; (c) evaluating MS locations via heuristics and constraints related to terrain, MS velocity and MS path extrapolation, and (d) adjusting likely MS locations. The system is useful for 911 emergency calls, tracking, routing, people and animal location including applications for confinement to and exclusion from certain areas.

Claims

1. A method for locating a mobile unit (M) using wireless signal data obtained from transmissions between the mobile unit M and one or more of a plurality of terrestrial wireless communication stations, comprising:

receiving, for an instance of locating the mobile unit M, M location data obtained using information from two way wireless transmissions between the mobile unit M at an unknown terrestrial location, and one or more of the communication stations;

first obtaining a first location estimate for M from a first location technique, wherein the first location technique determines said first location estimate using one or more values (V) obtained using the M location data, wherein each value V is indicative of a difference in arrival times of the wireless transmissions between;

(i) the mobile unit M and one of the one or more communication stations, and (ii) the mobile unit M and a different one of the one or more communication stations;

wherein the step of first obtaining determines the first location estimate relative to known terrestrial locations where each the one communication station and the different communication station reside when a corresponding one of the wireless transmissions is communicated with the mobile unit M;

second obtaining a second location estimate for M using a second location technique, wherein the second location technique determines said second location estimate using one or more occurrences of directional data obtained using the M location data, wherein each occurrence of the directional data is indicative of an angular orientation about one of the communication stations (CS) of a direction of the wireless transmissions to CS from the mobile unit M;

determining a resulting location estimate of the mobile unit M, wherein at least one of the following substeps (i) and (ii) is performed;

(i) determining one or more values for indicating which of said first and second location estimates is preferred, and (ii) combining said first and second location estimates for determining said resulting location estimate;

wherein the resulting location estimate identifies a likely location of the mobile unit M relative to one or more fixed positions on the earth;

outputting said resulting location estimate of the mobile unit M.

2. The method of claim 1, wherein said step of first obtaining includes providing at least one of said values V to a site remote from the mobile unit M for determining said first location estimate.

3. The method of claim 1, wherein at least one of:

(1) said first location technique,

(2) said second location technique, and

(3) said step of determining a resulting location estimate includes a step of determining a likely geographical location of the mobile unit M, wherein one or more of (d1)-(d3) following hold;

(d1) the step of determining a likely geographical location is dependent upon multipath data obtained from wireless signal multipath information communicated between the mobile unit M and the communication stations,

(d2) the step of determining a likely geographical location is dependent upon (i) and (ii) following;

(i) a representation of each of a plurality of geographical locations and (ii) for each of the geographical locations, corresponding multipath information previously obtained using transmissions between one or more mobile units and the communication stations when the one or more mobile units transmitted at some earlier time from approximately a same location as the geographical location, and

(d3) the step of determining a likely geographical location includes a step of selecting one or more of the geographical location representations that are likely to be approximate to the unknown location for M.

4. The method of claim 1, wherein at least one of said steps of first and second obtaining are performed at a site not co-located with M.

5. The method of claim 1, wherein said step of outputting includes transmitting said resulting location estimate via one of:

a public telephone network and the Internet.

6. The method of claim 1, wherein at least one of said first and second location estimates is not substantially dependent upon a value that the other of said first and second location estimates is substantially dependent upon.

7. The method of claim 1, wherein:

(i) said first location estimate is substantially dependent upon a first value for wireless signals communicated between the mobile unit M, and at least one of the communication stations, and (ii) said second location estimate is substantially dependent upon a second value for wireless signals communicated between the mobile unit M, and at least one of the communication stations;

wherein said first location estimate is not substantially dependent on said second value, and said second location estimate is not substantially dependent on said first location estimate.

8. The method of claim 1, further including a step of receiving, via a communications network, a signal by a user of the mobile unit M for initiating the instance of locating said mobile unit M.

9. The method of claim 1, wherein said wireless transmissions include two way communication of voice data between the mobile unit M and the one or more communication stations.

10. The method of claim 1, wherein said mobile unit M is a hand-held device for wirelessly communicating via a telephony network.

11. The method of claim 1, wherein the two way wireless transmissions pass through intermediary equipment included in a mobile base station.

12. The method of claim 1, wherein said step of determining a resulting location estimate includes receiving M location information from a vehicle for locating the mobile unit M, wherein said M location information is obtained using one or more of a direction of transmission and signal strength from wireless transmissions by the mobile unit M.

13. The method of claim 1, wherein said step of receiving includes receiving said M location data from the Internet.

14. The method of claim 1, wherein said resulting location estimate includes an identification of a roadway for identifying the likely location of the mobile unit M relative to said fixed positions.

15. The method of claim 1, wherein for an additional instance of locating the mobile unit M, one of said steps of first and second obtaining is not performed when a corresponding input for the location estimator of the one step is unavailable.

16. The method of claim 1, wherein said step of combining is performed, and said step of combining includes deriving said resulting location estimate as more dependent upon one of said first and second location estimates deemed to be a better estimate of the location of the mobile unit M.

17. The method of claim 1, wherein said step of determining the resulting location estimate includes using a coverage area analysis technique (CA), wherein when CA is supplied with input data obtained from at least one wireless signal transmission between the mobile unit M_a and one of the communication stations (CS₁), then CA uses an area that is substantially indicative of a coverage area about the communication station CS₁ for locating the mobile unit M_a.

18. A mobile unit location system, comprising:

a network interface for receiving one or more requests from a communications network, wherein each request is for locating, at one or more unknown terrestrial locations, a corresponding mobile unit of a plurality of mobile units, wherein during an instance of locating the corresponding mobile unit, there is two way wireless communication available between the corresponding mobile unit and at least one of a plurality of terrestrial communication stations;

a location estimator gateway for contacting one or more of a plurality of location estimators in response to each of said requests;

wherein for each of said one or more requests, each of said one or more location estimators contacted for the request, determines at least one estimate of a location of the corresponding mobile unit for the request;

wherein for at least one of the corresponding mobile units M, and for one of said requests (R) for locating the mobile unit M, said location estimator gateway contacts one or more of the location estimators resulting in first and second of the location estimates for the request R, each of said first and second location estimates having one or more of a geographical extent and location of the mobile unit M;

wherein the first location estimate of the mobile unit M is dependent upon a difference in signal time delays of wireless signals between;

(i) the mobile unit being located, and (ii) each of at least two of the terrestrial communication stations;

wherein the second location estimate of the mobile unit M is dependent upon directional data of wireless signals from the mobile unit being located to at least one of the terrestrial communication stations (CS) for determining a direction from CS toward the mobile unit being located;

a location determiner for determining a resulting location of the mobile unit M, wherein said location determiner receives said first and second location estimates and performs at least one of (i) and (ii) following;

(i) determines information indicative of which of said first and second location estimates is a more likely location of the mobile unit M, and (ii) combines said first and second location estimates for determining said resulting location estimate;

wherein the resulting location estimate identifies a location of the mobile unit M relative to one or more fixed positions on the earth;

an output gateway for transmitting the resulting location estimate of the mobile unit M to a corresponding destination, wherein the corresponding destination also corresponds to one of the requests for locating the mobile unit M.

19. A method for locating a plurality of mobile stations using wireless signal measurements obtained from transmissions between said mobile stations and a plurality of terrestrial communication stations, wherein each of said communication stations includes one or more of a transmitter and a receiver for wirelessly communicating with said mobile stations, comprising:

receiving, for locating each of a first and a second of the mobile stations, a corresponding a location request, wherein the first and second mobile stations are each capable of wireless two way communication with the communication stations;

requesting, for locating each of the first and second of the mobile stations, activation of a corresponding one or more mobile station location estimators, wherein (A) and (B) following hold;

(A) when said corresponding one or more location estimators for locating the first mobile station are supplied with their corresponding input data having values obtained from wireless signal measurements that are, in turn, obtained via transmissions between said first mobile station and one or more of the communication stations, said corresponding location estimators perform at least the techniques (T1), and (T2) following, wherein the first mobile station is an instance of each of the mobile stations M_i, for i=1, 2 respectively for each of the techniques (T1) and (T2); and

(B) when said corresponding one or more location estimators for locating the second mobile station are supplied their corresponding input data having values obtained from wireless signal measurements that are, in turn, obtained via transmissions between said second mobile station and one or more of the communication stations, said corresponding location estimators for locating the second mobile station perform at least one of the techniques (T3) and (T4) following, wherein the second mobile station is an instance of at least one of the mobile stations M_i, for i=3 or 4 for the corresponding at least one of the techniques (T3) and (T4) performed;

(T1) a first technique for determining at least one location estimate or locus for locating one or more of the mobile stations (M₁), wherein for locating the mobile station M₁, an instance of said corresponding input data indicative of one of;

a time of arrival of wireless signals, and a time difference of arrival of wireless signals transmitted between the mobile station M₁ and at least one of the communications stations (CS₁) is used for determining a range of the mobile station M₁ from CS₁, said range varying with varying values of the timing measurements, wherein at least one of the transmitted signals is from the mobile station M₁ to CS₁, and wherein said first technique outputs the at least one location estimate or locus from a site different from the location of the mobile station M₁;

(T2) a second technique for determining one or more candidate locations for locating one or more of the mobile stations (M₂), wherein for locating the mobile station M₂, each of said candidate locations is determined using, for at least some one of the communication stations (CS₂), data indicative of a direction of arrival of a wireless signal received at CS₂ and transmitted from the mobile station M₂;

(T3) a third technique for locating one or more of the mobile stations (M₃), wherein for locating the mobile station M₃, a location estimate is determined using a coverage area analysis technique (CA), wherein when CA is supplied with input data obtained from at least one wireless signal transmission between the mobile station M₃ and one of the communication stations (CS₁), then CA uses an area that is substantially indicative of a coverage area about the communication station CS₁ for locating the mobile station M₃;

(T4)

a fourth technique, wherein said fourth technique provides a pattern recognizer for estimating a location of one or more of the mobile stations (M₄), wherein said location estimate for the mobile station M₄ is derived from a pattern of multipath wireless signal characteristics for wireless signals communicated between;

(a) one or more of the communication stations, and (b) said mobile station M₄;

first obtaining, from said one or more location estimators for locating the first mobile station, first location information from the corresponding location estimators for locating the first mobile station, wherein the first location information includes;

an instance of the at least one location estimate or locus for locating the first mobile station that uses the first technique, and an instance of the one or more candidate locations for locating the first mobile station that uses the second technique;

first determining a first resulting location estimate of the first mobile station using said first location information;

second obtaining, from said one or more location estimators for locating the second mobile station, second location information from the corresponding location estimators for locating the second mobile station, wherein the second location information includes at least one of;

a location of the second mobile station that uses the third technique, and a location of the second mobile station that uses the fourth technique; and

second determining a second resulting location estimate of the second mobile station using said second location information.