System and method for wireless coverage detection

• US 7,356,340 B2
• Filed: 08/02/2004
• Issued: 04/08/2008
• Est. Priority Date: 08/02/2004
• Status: Expired due to Fees

• Current Assignee: Agilent Technologies, Inc.
• Original Assignee: Agilent Technologies, Inc.
• Inventors: Hamilton, Bruce
• Primary Examiner(s): D AGOSTA, STEPHEN M
• Application Number:
  US10/909,814
• Publication Number:
  US 20060025142A1
• Time in Patent Office: 1,345 Days
• Field of Search: 455/67.1, 455/423, 455/424, 455/425, 455/446, 455/447, 702/189, 702/190, 702/191, 702/193, 702/194, 702/195
• US Class Current: 455/446
• CPC Class Codes: H04W 16/18 Network planning tools
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 24/08 Testing, supervising or monitoring using real traffic

Abstract

A system and method is shown for determining the spatial boundary of certain measurable phenomena, such as broadcast signals, at various locations within geographical areas covered by the phenomenon. Data representing relative signal quality at various locations within the geographical area is created within a mobile device, such as a cell phone capable of receiving the phenomenon. The data is stored and refined within the device so as to define weak signal quality areas within at least a portion of the geographical area traveled by the mobile device. The refinement, which in one embodiment comprises coalescing and splitting stored data locations in the device allows for long storage periods by reducing memory requirements. By devoting the majority of memory to locations in the vicinity of the good/bad boundary, the most detailed picture possible of the boundary is achieved for a given amount of memory. By collecting such data from a plurality of such devices, a central system can map the signal strength over the entire geographical area.

Claims

1. A method for determining the spatial boundary of broadcast signal reception quality at various locations within geographical areas;

said method comprising;

measuring relative quality of certain of said broadcast signal reception quality at a defined region within said geographical area, said measuring occurring within a mobile device and resulting in measured data;

said defined region being defined by the movement of said mobile device; and

maintaining within said device said measured data so as to define poor quality areas within at least a portion of said defined region, wherein said maintaining comprises storing within data cells instances of poor quality locations within said defined region and from time to time reassessing said data cells, wherein said reassessing comprises reprocessing to collapse measured data stored within said device so that certain of said data cells form a single data cell,

wherein said measured data is a count of poor signal quality maintained individually for a plurality of location cells within said geographical area, and wherein said device increments said bad signal count with respect to the cell location of said experienced poor quality whenever said device experiences an instance of poor quality.

2. The method of claim 1 further comprising:

from time to time redefining said defined region for each said mobile device.

3. The method of claim 1 wherein said reassessing further comprises splitting certain data cells to form several data cells.

4. The method of claim 1 wherein said reprocessing to collapse comprises combining those cells whose count density of instances of poor quality are approximately equal.

5. The method of claim 1 wherein said device is an end-user device.

6. The method of claim 5 wherein said end-user device is a cellular telephone.

7. The method of claim 1 further comprising:

communicating defined ones of said poor quality areas from said device to a control system.

8. The method of claim 7 wherein the time span between said communicating is at least one day.

9. The method of claim 1 wherein said defined region is redefined based on the physical areas visited by said device.

10. The method of claim 1 wherein said defined region is a determined home area of said device.

11. The method of claim 1 wherein said measured data is a count of bad quality at various locations within said geographical area over a period of time.

12. The method of claim 1 wherein said poor signal quality is determined by at least one criterion from the group consisting of:

(a) signal strength at periodic intervals, (b) in a communication system whenever a connection is dropped, and (c) whenever the user tries to establish a communication connection and fails.

13. A hand-held mobile device for receiving wireless signals, said device comprising:

a poor signal quality indicator;

a location detector;

memory for storing poor signal quality indications corresponding to a plurality of detected locations; and

a processor for collapsing certain of said locations within said device into a single location, said collapsing combining those locations whose incremented count densities are approximately equal,

wherein said processor is further operable for splitting certain of said locations into multiple locations, said split certain cells being cells on the boundary of said poor signal quality indications.

14. The hand-held mobile device of claim 13 wherein said device is one selected from the list of:

cellular telephones, PDAs, computers, navigation systems, consumer devices, vehicle control processors.

15. The hand-held mobile device of claim 13 wherein said poor signal quality indications are determined based upon at least one of the following occurring with respect to said device:

(a) low signal strength at periodic intervals, (b) dropping of a connection, and (c) failed connection attempt.

16. The hand-held mobile device of claim 13 wherein said poor signal quality indication is an incremented count maintained within said device on a location by location basis, said locations being actual locations of each said device at the time said indication is incremented.

17. The hand-held mobile device of claim 16 wherein said incremented count is controlled by a logarithmic counter within said device.

18. The hand-held mobile device of claim 16 wherein said incremented count is organized as a quadtree.

19. The hand-held mobile device of claim 13 further comprising:

a transmitter within said device for sending from time to time said poor signal quality indications for at least one of said detected locations to a control point external to said device.

20. The hand-held mobile device of claim 13 further comprising:

storage for holding data from one geographical area while said device is in a different geographical area.

21. A cellular system for providing wireless communication to a plurality of wireless devices, said system comprising:

means for providing at least one source of wireless RF transmission broadcast over a widespread geographical area to a plurality of said wireless devices;

means for accepting from a plurality of said wireless devices data collected and stored by each said wireless device over a period of time, said data pertaining to locations of poor signal quality determined by said wireless device, said locations being within an area defined by each of said wireless devices;

means for determining from accepted data from a plurality of said wireless devices at least one boundary of said poor signal quality wherein no one of said wireless devices need collect all of the data necessary to determine said boundary; and

means for coalescing certain of said locations within each said device, and means for splitting other of said locations within each said device.

22. The cellular system of claim 21, further comprising:

means for redefining said area defined by each of said wireless devices, said redefining dependent upon the actual geographical area traveled by a user of said device.