Locating external interference in a wireless network
A method for localizing interference uses data available to wireless communication networks to determine probabilities of a source of external interference being located at a plurality of predetermined locations. In a heterogeneous network, data from sites using omnidirectional antennas can be combined with data from multi-sector sites to accurately locate a source of interference.
1. A method for locating a source of interference affecting a wireless telecommunications network, the method comprising:
generating a first probability map that indicates probabilities of the source of interference being disposed in respective geographic locations;
receiving interference data for at least one omnidirectional antenna that is disposed in a location covered by the map;
generating a contour map of interference levels using the received interference data; and
generating a second probability map by re-assigning probability values of the first probability map according to contours of the contour map,
wherein generating the contour map includes generating a plurality of bounded shapes, each shape having a perimeter line that represents a particular level of interference.
2. The method of claim 1 , wherein the first probability map includes an unbounded probability area originating from a directional antenna location.
3. The method of claim 2 , wherein re-assigning the probability values of the first map includes bounding the unbounded probability area.
4. The method of claim 2 , wherein the first probability map includes a second unbounded probability area, and re-assigning the probability values includes reducing probability values of the second unbounded probability area to zero.
5. The method of claim 1 , wherein the first probability map comprises a plurality of pixels, and each pixel has an assigned probability value that represents a probability that the source of interference is located in a geographic area corresponding to the pixel.
6. The method of claim 1 , further comprising:
comparing characteristics of interference used to generate the first probability map to characteristics of the received interference data from the at least one omnidirectional antenna to determine whether the interference used to generate the first probability map has the same characteristics as interference associated with the received interference data.
7. The method of claim 1 , further comprising:
assigning an attenuation value to each bounded shape,
wherein generating the second probability map includes re-assigning probability values of the first map according to the attenuation values of the bounded shapes.
8. The method of claim 1 , wherein generating the contour map includes performing Delaunay triangulation to connect locations for the omnidirectional antennas, and the contours include contour lines between sides of the Delaunay triangles.
9. The method of claim 8 , wherein at least one of the locations for the omnidirectional antennas used to generate the contour map is a virtual cell site at which no physical cell site exists.
10. The method of claim 1 , wherein the interference is external interference that is not caused by the wireless telecommunications network.
11. The method of claim 10 , further comprising:
resolving the external interference.
12. A wireless telecommunications system comprising a spectrum analysis server configured to locate a source of interference external to a wireless telecommunications network, the spectrum analysis server comprising a processor and a non-transitory computer readable medium with instructions stored thereon which, when executed by the processor, perform the following steps:
generating a first probability map that indicates probabilities of the source of interference being disposed in respective geographic locations;
receiving interference data for at least one omnidirectional antenna that is disposed in a location covered by the map;
generating a contour map of interference levels using the received interference data; and
generating a second probability map by re-assigning probability values of the first probability map according to contours of the contour map,
wherein generating the contour map includes generating a plurality of bounded shapes, each shape having a perimeter line that represents a particular level of interference.
13. The system of claim 12 , wherein the first probability map includes an unbounded probability area originating from a directional antenna location.
14. The system of claim 13 , wherein re-assigning the probability values of the first map includes bounding the unbounded probability area.
15. The system of claim 13 , wherein the first probability map includes a second unbounded probability area, and re-assigning the probability values includes reducing probability values of the second unbounded probability area to zero.
16. The system of claim 12 , wherein the first probability map comprises a plurality of pixels, and each pixel has an assigned probability value that represents a probability that the source of interference is located in a geographic area corresponding to the pixel.
17. The system of claim 12 , wherein the interference data is received from a performance management server of the wireless telecommunications network that is coupled to the at least one omnidirectional antenna.
18. The system of claim 12 , wherein the steps executed by the processor further comprise:
assigning an attenuation value to each bounded shape,
wherein generating the second probability map includes re-assigning probability values of the first map according to the attenuation values of the bounded shapes.
19. A method for locating a source of interference affecting a wireless telecommunications network, the method comprising:
generating a first probability map that indicates probabilities of the source of interference being disposed in respective geographic locations;
receiving interference data for at least one omnidirectional antenna that is disposed in a location covered by the map;
generating a contour map of interference levels using the received interference data; and
generating a second probability map by re-assigning probability values of the first probability map according to contours of the contour map,
wherein the first probability map comprises a plurality of pixels, and each pixel has an assigned probability value that represents a probability that the source of interference is located in a geographic area corresponding to the pixel.