System and method for conducting wireless site surveys

• US 8,868,002 B2
• Filed: 08/31/2011
• Issued: 10/21/2014
• Est. Priority Date: 08/31/2011
• Status: Active Grant

• Current Assignee: Cambium Networks Limited (Cambium Networks Corporation)
• Original Assignee: Xirrus Incorporated
• Inventors: Horner, Jack Michael, Gates, Dirk Ion, Sauter, Kurt Karl, Chernyakhovsky, Alexander, Miller, Bruce Anthony
• Primary Examiner(s): Urban, Edward
• Assistant Examiner(s): Mathew, Max
• Application Number:
  US13/222,570
• Publication Number:
  US 20130052961A1
• Time in Patent Office: 1,147 Days
• Field of Search: 455/67.11, 455/67.13, 455/67.14, 455/67.7, 455/446
• US Class Current: 455/67.11
• CPC Class Codes: H04W 16/18 Network planning tools
• CPC Class Codes: H04W 24/08 Testing, supervising or monitoring using real traffic

Abstract

A method for surveying a site for installation of wireless access points is provided. A map of the site under survey is displayed. User input relating to the position of a first wireless device at the site is received. User input relating to the position of a second wireless device at the site is also received. Wireless signals broadcast by the second wireless device are measured using the first wireless device to obtain signal strength values corresponding to the strength of the wireless signals. Attenuation values based on the signal strength values are calculated and assigned to features on the map of the site under survey.

Claims

1. A method for surveying a site for installation of wireless access points comprising:

displaying a map of the site under survey;

receiving user input relating to a first position of a first wireless device at the site;

receiving user input relating to a second position of a second wireless device at the site;

measuring, using the first wireless device, one or more wireless signals broadcast by the second wireless device to obtain respective signal strength values corresponding to the strength of the wireless signals;

calculating one or more attenuation values based on the one or more signal strength values and the user input relating to the first position of the first wireless device and to the second position of the second wireless device; and

respectively assigning at least one of the attenuation values to at least one feature of the map of the site under survey.

2. The method of claim 1 further comprising:

analyzing the one or more attenuation values to identify a corresponding wireless coverage pattern for the second wireless device at the site under survey;

determining an amount of wireless access points for installation at the site based on the wireless coverage pattern; and

determining respective installation locations at the site under survey for the wireless access points based on the wireless coverage pattern.

3. The method of claim 1 further comprising:

obtaining a baseline signal strength value using the first wireless device from a first location where the first location relative to the second wireless device; and

obtaining a perceived signal strength value using the first wireless device from a second location that is different from the first location.

4. The method of claim 3 further comprising:

determining free space path loss at the site under survey to obtain an expected attenuation value;

calculating a relative attenuation value by subtracting the perceived signal strength value from the baseline signal strength value; and

calculating an additional attenuation value by subtracting the expected attenuation value from the relative attenuation value.

5. The method of claim 4 where the at least one feature of the map respectively corresponds to at least one physical structure at the site under survey.

6. The method of claim 5 further comprising:

analyzing the map to automatically identify one or more features of the map that respectively correspond to at least one physical structure at the site under survey;

automatically determining that one of the identified features of the map intersects a path between the first wireless device and the second wireless device; and

automatically assigning the additional attenuation value to the feature of the map that intersects the path between the first wireless device and the second wireless device.

7. The method of claim 4 further comprising:

dividing the map of the site under survey into a grid having a plurality of grid cells; and

assigning the additional attenuation value with one of the grid cells.

8. The method of claim 4 further comprising generating an attenuation profile for the site under survey that includes one or more additional attenuation values respectively assigned to one or more features of the map.

9. The method of claim 1 where the first wireless device is a wireless measurement device and the second wireless device is a wireless access point.

10. The method of claim 1 further comprising measuring, using the second wireless device, one or more signal strength values respectively assigned to one or more wireless signals broadcast by the first wireless device.

11. A system for determining attenuation of wireless signals broadcast by a wireless device at a wireless survey site comprising:

a map display module that displays a map of the site under survey;

a signal strength measurement module that measures, using a first wireless device at the site under survey, one or more wireless signals broadcast by second wireless device at the site under survey, to obtain one or more signal strength values corresponding to the strength of the one or more wireless signals; and

an attenuation calculation module that calculates one or more attenuation values based on the one or more signal strength values and based on user input respectively relating to a measurement location and a position of the first wireless device and the second wireless site at the site under survey such that the one or more attenuation values are assignable to at least one feature of the map of the site under survey.

12. The system of claim 11 where:

the one or more attenuation values are analyzed to identify a corresponding wireless coverage pattern for the wireless device at the site under survey;

an amount of wireless access points for installation at the site is determined based on the wireless coverage pattern; and

one or more respective installation locations at the site under survey for the wireless access points is determined based on the wireless coverage pattern.

13. The system of claim 11 where:

the signal strength measurement module measures a baseline signal strength from a first location relative to the wireless device in order to obtain a baseline signal strength value; and

the signal strength measurement module measures a perceived signal strength from a second location that is different than the first location in order to obtain a perceived signal strength value.

14. The system of claim 13 where:

the attenuation calculation module determines free space path loss at the site under survey to obtain an expected attenuation value;

the attenuation calculation module calculates a relative attenuation value by subtracting the perceived signal strength value from the baseline signal strength value; and

the attenuation calculation module calculates an additional attenuation value by subtracting the expected attenuation value from the relative attenuation value.

15. The system of claim 14 where at least one of the features of the map respectively corresponds to at least one physical structure at the site under survey.

16. The system of claim 15 further comprising a map analysis module that:

analyzes the map to automatically identify one or more features of the map that respectively correspond to at least one physical structures at the site under survey;

automatically determines that one of the identified features of the map intersects a path between the system and the wireless device; and

automatically assigns the additional attenuation value to the features of the map that intersects the path between the first wireless device and the second wireless device.

17. The system of claim 14 where:

the map is divided into a grid having a plurality of grid cells that respectively correspond to an area at the site; and

the additional attenuation value is assigned to one of the grid cells.

18. The system of claim 14 where an attenuation profile for the site under survey is generated that includes one or more additional attenuation values respectively assigned to one or more features of the map.

19. The system of claim 11 where:

the map display module, signal strength measurement module, and attenuation calculation module are provided in a wireless measurement device; and

the wireless device is a wireless access point.

20. The system of claim 11 where:

the map display module, signal strength measurement module, and attenuation calculation module are provided in a wireless measurement device that broadcasts wireless signals; and

the wireless device measures one or more signal strength values respectively corresponding to the one or more wireless signals broadcast by the wireless measurement device.