Method and apparatus for detecting interference using correlation
AssigneeISCO International, LLC
InventorSean S. Cordone
Life of this patent
Estimating the term…
Abstract
A system and/or a method for detecting interference using correlation may be used in a communication system to protect against, or to report the presence of, narrowband interference, which has deleterious effects on the performance of the wideband communication system. The interference detection system described herein may be used to determine presence of narrowband interference by calculating correlation factors for a plurality of narrowband channels disposed within the wideband communication system and comparing the correlation factors with a threshold correlation factor.
Claims16
A method, performed by a mobile unit or base station, for detecting narrowband interference in a wideband communication signal having a frequency bandwidth with a narrowband channel disposed therein, the method comprising:
- scanning the narrowband channel a plurality of times to determine a plurality of signal strengths at each of the plurality of scans;
- determining a correlation factor for the narrowband channel based on the plurality of signal strengths;
- comparing the correlation factor with a threshold correlation factor to determine presence of the narrowband interference in the narrowband channel;
- wherein scanning the narrowband channel a plurality of times further comprises
- continuously scanning the narrowband channel to generate a plurality of narrowband scans, and
- storing a plurality of signal strength observations, each of the plurality of signal strength observations corresponding to one of the plurality of narrowband scans;
- and
- wherein determining the correlation factor further comprises using a subset of the plurality of signal strength observations, wherein the subset of the plurality of signal strength observations are the most recent of the plurality of signal strength observations.
A method, performed by a mobile unit or base station, for detecting narrowband interference in a wideband communication signal having a frequency bandwidth with a plurality of narrowband channels disposed therein, the method comprising:
- scanning the plurality of narrowband channels a plurality of times to determine a plurality of signal strengths, each of the plurality of signal strengths corresponding to a particular scan of a particular narrowband channel;
- selecting a first number of narrowband channels, wherein the first number of narrowband channels have highest signal strengths for the first scan;
- selecting a second number of narrowband channels, wherein the second number of narrowband channels have highest signal strengths for the second scan;
- determining if any of the first number of narrowband channels corresponds to any of the second number of narrowband channels to identify a narrowband channel having interference;
- determining a first threshold based on the plurality of narrowband signal strengths for the first number of narrowband channels;
- and
- determining a second threshold based on the plurality of narrowband signal strengths for the second number of narrowband channels.
An interference detection system for detecting narrowband interference within a wideband communication signal with a plurality of narrowband channels disposed therein, the system comprising:
- a wideband signal receiver to receive the wideband signal;
- a narrowband signal strength scanner to scan a plurality of narrowband channels to determine narrowband channel signal strengths for each of the plurality of scans;
- and
- a digital signal processor to process the plurality of narrowband channel signal strengths for each of the plurality of scans to determine a plurality of correlation factors and to compare the plurality of correlation factors to a threshold correlation factor to determine a narrowband channel having the narrowband interference, wherein the digital signal processor is further to:
- determine average signal strengths for each of the plurality of scans;
- calculate a plurality of threshold signal strengths corresponding to the plurality of scans based on the average signal strengths for each of the plurality of scans;
- and
- determine a group of narrowband channels for each of the plurality of scans having signal strengths above the threshold signal strength corresponding to each of the plurality of scans.
Dependencies are inferred from the claim text.