Method and apparatus for generating a signal strength model for an access point at an arbitrary location

• US 20050245252A1
• Filed: 04/28/2004
• Published: 11/03/2005
• Est. Priority Date: 04/28/2004
• Status: Active Grant

• Current Assignee: Avaya Incorporated
• Original Assignee: Avaya Incorporated
• Inventors: Krishnakumar, Anjur S., Krishnan, P., Kappes, Martin
• Granted Patent: US 7,583,961 B2
• Time in Patent Office: Days
• US Class Current: 455/423
• CPC Class Codes: H04W 16/18 Network planning tools
• CPC Class Codes: H04W 16/20 for indoor coverage or short range network deployment
• CPC Class Codes: H04W 24/02 Arrangements for optimising operational condition

Abstract

A method and apparatus are provided for obtaining a signal strength model for an access point at an arbitrary location, q, at a site. Signal strength measurements are obtained for each of n sampling points; the signal strength received at the arbitrary location, q, is computed from each of said sampling points (for example, using reciprocity principles); signal strength estimates corresponding to the signal received at the sampling points from the arbitrary location are computed; and a signal strength model is determined for an access point positioned at the arbitrary location, q.

Claims

1. A method for obtaining a signal strength model for an access point at an arbitrary location, q, at a site, comprising:

obtaining signal strength measurements for each of n sampling points;

computing the signal strength received at said arbitrary location, q, from each of said sampling points;

obtaining signal strength estimates corresponding to the signal received at said sampling points from said arbitrary location; and

determining a signal strength model for an access point positioned at said arbitrary location, q.

2. The method of claim 1, wherein said step of determining a signal strength model further comprises the steps of:

smoothing the obtained signal strength measurements into a set;

dividing said site into a grid of squares of known size; and

interpolating said set across two dimensions to form a scalar array to estimate said received signal strength at the center of each grid square.

3. The method of claim 2, wherein said scalar array comprises a signal strength model for an access point positioned at the arbitrary location, q.

4. The method of claim 2, wherein said step of smoothing employs a generalized additive model (GAM).

5. The method of claim 2, wherein said step of interpolating comprises an Akima spline interpolation.

6. The method of claim 1, wherein said collecting step further comprises the step of placing a transceiver at each of said sampling points.

7. The method of claim 1, wherein said step of computing the signal strength received at said arbitrary location, q, from each of said sampling points applies reciprocity principles.

8. The method of claim 1, wherein said site is being evaluated for a deployment of a wireless network containing said access point.

9. An apparatus for obtaining a signal strength model for an access point at an arbitrary location, q, at a site, comprising:

a memory; and

at least one processor, coupled to the memory, operative to;

obtain signal strength measurements for each of n sampling points;

compute the signal strength received at said arbitrary location, q, from each of said sampling points;

obtain signal strength estimates corresponding to the signal received at said sampling points from said arbitrary location; and

determine a signal strength model for an access point positioned at said arbitrary location, q.

10. The apparatus of claim 9, wherein said processor is further configured to:

smooth the obtained signal strength measurements into a set;

divide said site into a grid of squares of known size; and

interpolate said set across two dimensions to form a scalar array to estimate said received signal strength at the center of each grid square.

11. The apparatus of claim 10, wherein said scalar array the signal strength model for an access point positioned at the arbitrary location, q.

12. The apparatus of claim 10, wherein said processor employs a generalized additive model (GAM) to implement said smoothing.

13. The apparatus of claim 10, wherein said processor employs an Akima spline interpolation.

14. The apparatus of claim 9, wherein said processor is further configured to apply reciprocity principles to compute the signal strength received at said arbitrary location, q, from each of said sampling points.

15. The apparatus of claim 9, wherein said site is being evaluated for a deployment of a wireless network containing said access point.

16. A method for obtaining a signal strength model for an access point at an arbitrary location, q, at a site, comprising:

obtaining signal strength measurements for each of n sampling points;

for each sampling point, generating a model for the signal strength received at said sampling point when said access point is placed at an arbitrary location, q;

computing a signal strength received at the n sampling points when said access point is placed at said arbitrary location, q; and

determining said signal strength model for said access point positioned at said arbitrary location, q.

17. The method of claim 16, wherein said step of determining said signal strength model further comprises the steps of:

smoothing the obtained signal strength measurements into a set;

dividing said site into a grid of squares of known size; and

interpolating said set across two dimensions to form a scalar array to estimate said received signal strength at the center of each grid square.

18. The method of claim 17, wherein said scalar array comprises a signal strength model for an access point positioned at the arbitrary location, q.

19. The method of claim 16, wherein said site is being evaluated for a deployment of a wireless network containing said access point.

20. The method of claim 16, wherein said sampling points have a fixed location.