LOCATION MEASUREMENT ACQUISITION ADAPTIVE OPTIMIZATION

• US 20110090122A1
• Filed: 10/15/2009
• Published: 04/21/2011
• Est. Priority Date: 10/15/2009
• Status: Active Grant

• Current Assignee: CommScope Technologies, LLC (CommScope Holding Company, Inc.)
• Original Assignee: Andrew LLC (CommScope Holding Company, Inc.)
• Inventors: Winterbottom, James, Thomson, Martin
• Granted Patent: US 8,289,210 B2
• Time in Patent Office: Days
• US Class Current: 342/450
• CPC Class Codes: G01S 5/0244 Accuracy or reliability of position solution or of measurements contributing thereto

Abstract

A disclosed method uses the results of location queries to tune the value of measurements of a property to obtain a statistically representative measurement for geo location. As location requests arrive, a current measurement value associated with the serving area or location is used to determine the number of measurements to obtained; the resulting uncertainty is mapped against the number of measurements required to determine that value. If additional measurements are required to achieve the target uncertainty in the result, this is recorded. The process relies on empirical observations and has the additional advantage of being blind to the actual network topology. This approach by its own nature automatically takes into account network changes whether known or unknown.

Claims

1. A method of adaptively optimizing the amount of measurements of a property required to achieve a desired level of uncertainty in a service area, the method comprising:

establishing an initial amount (n) of measurements required of a property;

receiving a location request;

obtaining n measurements of the property;

estimating a location associated with the location request based on at least the n measurements of the property;

determining the level of uncertainty associated with the estimated location;

comparing the determined level of uncertainty with at least one threshold, wherein the threshold is based on the desired level of uncertainty; and

tuning the amount of measurements n required of the property based upon the comparison.

2. The method of claim 1, further comprising reporting the location to the sender of the location request.

3. The method of claim 1, comprising:

establishing an initial amount (n_i) of measurements required for each of a plurality of properties (i);

obtaining n;

measurements for each of the i properties; and

,

estimating the location based on at least the n_i measurements; and

,

tuning the amount of measurements n_i required for at least one of the plurality of properties based on at least the comparison;

wherein n_i is the amount of measurements for the i^th property of the plurality of properties.

4. The method of claim 1, comprising filtering the level of uncertainty in the time domain.

5. The method of claim 1, comprising:

integrating successive levels of uncertainty to obtain the determined level of uncertainty.

6. The method of claim 1, comprising:

low pass filtering successive levels of uncertainty to obtain the determined level of uncertainty.

7. The method of claim 1, comprising:

obtaining a running average of the successive levels of uncertainty to obtain the determined level of uncertainty.

8. The method of claim 1 wherein the initial amount of measurements is determined as a result of a Monte Carlo simulation.

9. The method of claim 1, comprising:

increasing the number of measurements if the determined level of uncertainty is below the at least one threshold.

10. The method of claim 1, comprising:

decreasing the number of measurements if the determined level of uncertainty is above the at least one threshold.

11. The method of claim 1, wherein the initial amount of measurements is set by the network.

12. The method of claim 1, wherein the property is selected from the group consisting of signal strength, Return Trip Time (RTT), Return Trip Delay (RTD), Timing Advance (TA), Time of Arrival (TOA), Time Difference of Arrival (TDOA) and Angle of Arrival (AoA).

13. The method of claim 1, wherein the i properties are selected from the group consisting of signal strength, Return Trip Time (RTT), Return Trip Delay (RTD), Timing Advance (TA), Time of Arrival (TOA), Time Difference of Arrival (TDOA) and Angle of Arrival (AoA).

14. The method of claim 1, wherein the threshold is a percentage of the desired level of uncertainty.

15. A method to locate a mobile device within a predetermined level of uncertainty, comprising:

compiling data associated with location requests and the location estimates within a service area in a database;

associating in the database the amount of plural measurements of a property with the level of uncertainty of a location estimated using the plural measurements;

receiving a location request;

determining the level of uncertainty required for the location request;

selecting the amount of plural measurements associated with the level of uncertainty required based on the associations in the database;

obtaining plural measurements of a property in the amount selected;

obtaining a location estimate;

determining the level of uncertainty in the location estimate;

associating the number of plural measurements obtained and the determined level of uncertainty in the location estimate and compiling the association in the database; and

,

determining a new amount of measurements required for a desired level of uncertainty.

16. The method of claim 15, comprising increasing or decreasing the amount of plural measurements required to obtain the desired level of uncertainty based on the level of uncertainty in the location estimate.

17. The method of claim 15, wherein the property is selected from the group consisting of signal strength, Return Trip Time (RTT), Return Trip Delay (RTD), Timing Advance (TA), Time of Arrival (TOA), Time Difference of Arrival (TDOA) and Angle of Arrival (AoA).

18. In a service area subject to property fluctuations, a method of determining a nominal amount of plural measurements of a property required to obtain a predetermined level of uncertainty using actual location requests, the method comprising:

receiving a location request, estimating a location based on an predetermined level of uncertainty and an amount of property measurements used;

associating the amount of measurement samples of a property taken, the estimated location and the resulting level of uncertainty calculated from the estimated location using the measurement samples; and

adaptively tuning the associated nominal amount of property measurements based on the estimated location and its level of uncertainty.

19. The method of claim 18, wherein the property is selected from the group consisting of signal strength, Return Trip Time (RTT), Return Trip Delay (RTD), Timing Advance (TA), Time of Arrival (TOA), Time Difference of Arrival (TDOA) and Angle of Arrival (AoA).

20. A method of optimizing the nominal requirements associated with a wireless communications property comprising:

associating location estimates, number of property samples used in the location estimates and level of uncertainties of the location estimates in a historical database;

establishing nominal requirements based on the location database;

receiving a location request;

generating a location estimate according to the nominal requirements; and

,

adaptively updating the nominal requirements based on the location estimate.

21. The method of claim 20, wherein the nominal requirements comprise at least the number of measurement requested for each wireless communication property used to estimate the location.

22. The method of claim 20, comprising:

determining a level of uncertainty for the location estimate and comparing the level of uncertainty with a threshold and adaptively updating the nominal number based at least on the determined level of uncertainty

23. The method of claim 20, wherein the wireless communication property is selected from the group consisting of signal strength, Return Trip Time (RTT), Return Trip Delay (RTD), Timing Advance (TA), Time of Arrival (TOA), Time Difference of Arrival (TDOA) and Angle of Arrival (AoA).