# US 11,121,785 B2 · Detection and tracking of interferers in a RF spectrum with multi-lane processing > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,121,785 B2 - Document ID: US11121785B2 - Status: Granted - Kind: B2 - Application number: 16/738,258 - Filed: 2020-01-09 - Published: 2020-08-06 - Granted: 2021-09-14 - Earliest claimed: 2019-01-10 - Assignees: EXFO Inc. - Applicants: EXFO Inc. - Inventors: Martin Levesque - Web page: https://patentgrep.com/patent/US11121785B2 ## CPC - H04B 1/109: {by improving strong signal performance of the receiver when strong unwanted signals are present at the receiver input} - H04B 17/345: Interference values ({signal-to-interference ratio [SIR] or carrier-to-interference ratio [CIR]} H04B17/336) - H04B 1/1027: {assessing signal quality or detecting noise/interference for the received signal} - H04W 24/08: Testing, {supervising or monitoring} using real traffic - H04B: TRANSMISSION - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract An interference detection method and system and for providing information about at least one interference in I/Q data obtained over-the-air or detected on a link between a radio equipment controller (REC) and at least one radio equipment (RE). The method includes noise filtering a set of the FFTs into an averaged FFT, filtering the averaged FFT with a high-pass filter to remove low frequency components, applying a power threshold on the high-pass filtered FFT to select at least one candidate peak having a power greater than the power threshold; outputting information about the at least one candidate peak, which is a potential interference. The interference detection method further includes multi-lane processing and power shift compensation. ## Claims ### Claim 1 An interference detection method for providing information about at least one interference in I/Q data obtained over-the-air or detected on a link between a radio equipment controller (REC) and at least one radio equipment (RE), said I/Q data being provided as a plurality of Fast Fourier Transformation (FFT) streams, said interference causing a peak in said FFT streams the method comprising: noise filtering a set of said FFT streams into an averaged FFT; filtering the averaged FFT with a high-pass filter to remove low frequency components, thereby producing a high-pass filtered FFT; applying a power threshold on the high-pass filtered FFT to select at least one candidate peak having a power greater than said power threshold; outputting information about said at least one candidate peak, wherein said at least one candidate peak is a potential interference. ### Claim 2 (depends on 1) The interference detection method as claimed in claim 1, further comprising post high-pass noise filtering said high-pass filtered FFT after said filtering stage. ### Claim 3 (depends on 1) The interference detection method as claimed in claim 1, further comprising calculating a standard deviation of the high-pass filtered FFT and wherein said power threshold is a multiple of said standard deviation. ### Claim 4 (depends on 1) The interference detection method as claimed in claim 1, further comprising: splitting said filtering into multiple parallel filtering sub-stages, each filtering sub-stage of said multiple parallel filtering sub-stages being tuned differently to create a plurality of different high-pass filters; applying said power threshold in each of said multiple parallel filtering sub-stages to obtain a plurality of candidate peak lists; merging said plurality of candidate peak lists in a candidate peak merger. ### Claim 5 (depends on 1) The interference detection method as claimed in claim 1, wherein said filtering the averaged FFT with said high-pass filter further comprises applying a symmetry factor related to a symmetry of said at least one candidate peak thereby compensating for a power shift. ### Claim 6 (depends on 1) The interference detection method as claimed in claim 1, further comprising grouping ones of said at least one candidate peak into a grouped peak if said ones are separated by less than a maximum peak distance parameter. ### Claim 7 (depends on 1) The interference detection method as claimed in claim 1, further comprising repeating said steps of noise filtering, filtering and applying said power threshold for a next set of said FFT streams; tracking a presence of a tracked peak in said at least one candidate peak of said set and said next set to obtain a tracked peak; outputting information about said tracked peak. ### Claim 8 (depends on 7) The interference detection method as claimed in claim 7, wherein said tracking includes using a maximum peak movement parameter to match said at least one candidate peak of said set and said next set. ### Claim 9 (depends on 7) The interference detection method as claimed in claim 7, further comprising: accumulating said power of said tracked peak from said set of FFT streams and said next set of FFT streams into an accumulated power; identifying a status of said tracked peak as declared if said accumulated power is greater than a declare threshold; wherein said outputting information about said tracked peak further comprises outputting said status of said tracked peak. ### Claim 10 (depends on 9) The interference detection method as claimed in claim 9, further comprising calculating the standard deviation of the high-pass filtered FFT and wherein said declare threshold is a multiple of said standard deviation. ### Claim 11 (depends on 9) The interference detection method as claimed in claim 9, further comprising identifying said status of said tracked peak as clear if said accumulated power is smaller than a clear threshold, wherein said declare threshold is greater than said clear threshold. ### Claim 12 (depends on 11) The interference detection method as claimed in claim 11, further comprising calculating the standard deviation of the high-pass filtered FFT and wherein said clear threshold is a multiple of said standard deviation. ### Claim 13 (depends on 7) The interference detection method as claimed in claim 7, wherein said tracking said presence further comprises merging adjacent tracked peaks if said tracked peaks are closer than said maximum peak movement parameter by selecting a highest powered tracked peak. ### Claim 14 (depends on 1) A non-transitory computer-readable storage medium having computer readable code stored thereon for programming a test system to perform the steps of: obtaining I/Q data; processing the I/Q data to detect interferences according to claim 1; causing display of a user interface that includes a reporting of said interferences. ### Claim 15 (depends on 1) A test system comprising: a detector configured to obtain I/Q data; a processor; and memory storing instructions that, when executed, cause the processor to carry out the steps of claim 1.