Signal conditioning to mitigate interference impacting wireless communication links in radio access networks

• US 10,652,835 B2
• Filed: 05/24/2017
• Issued: 05/12/2020
• Est. Priority Date: 06/01/2016
• Status: Active Grant

• Current Assignee: ISCO International Inc.
• Original Assignee: ISCO International LLC
• Inventors: Tacconi, Pablo, Abdelmonem, Amr, Zia, Nauman
• Primary Examiner(s): Sobutka, Philip
• Application Number:
  US15/603,851
• Publication Number:
  US 20170353929A1
• Time in Patent Office: 1,084 Days
• Field of Search: 455 6711, 4552261, 455501
• CPC Class Codes: H04B 17/318 Received signal strength
• CPC Class Codes: H04W 28/04 Error control
• CPC Class Codes: H04W 52/225 Calculation of statistics, e.g. average, variance
• CPC Class Codes: H04W 52/243 taking into account interferences
• CPC Class Codes: H04W 52/42 in systems with time, space, frequency or polarisation diversity

Abstract

A system that incorporates aspects of the subject disclosure may perform operations including, for example, receiving, via an antenna, a signal generated by a communication device, detecting an interference in the signal, the interference generated by one or more transmitters unassociated with the communication device, and the interference determined from signal characteristics associated with a signaling protocol used by the one or more transmitters, and performing signal conditioning on the signal to reduce the interference. Other embodiments are disclosed.

Claims

1. A method, comprising:

receiving, by a circuit, a signal generated by a communication device;

detecting, by the circuit, a passive intermodulation interference in the signal, wherein the passive intermodulation interference is generated by one or more transmitters, wherein the passive intermodulation interference is detected by the circuit by;

determining signal characteristics of the signal;

determining expected signal characteristics associated with a signaling protocol used by the one or more transmitters; and

comparing the signal characteristics of the signal with the expected signal characteristics associated with the signaling protocol;

wherein the one or more transmitters are unassociated with the communication device generating the signal; and

performing, by the circuit, signal conditioning on the signal to reduce the passive intermodulation interference.

2. The method of claim 1, wherein the detecting comprises detecting in a time-domain that a power level of the signal exceeds a power level threshold.

3. The method of claim 2, wherein the power level threshold is determined according to a peak to average power ratio.

4. The method of claim 3, wherein the power level threshold is determined from expected power level characteristics of an uplink signal that is not subject to interference.

5. The method of claim 2, wherein the detecting comprises measuring a time-domain profile of the signal, and detecting the passive intermodulation interference by comparing the power level threshold to the time-domain profile.

6. The method of claim 5, wherein the time-domain profile is determined according to a mean calculation of a magnitude and power level of the signal, a median calculation of the magnitude and power level of the signal, a peak calculation of the magnitude and power level of the signal, a peak to average power ratio calculation of the signal, a peak to average ratio magnitude calculation of the signal, or any combination thereof.

7. The method of claim 1, wherein the signal conditioning is performed by reducing a power level of the signal in one or more portions of the signal in a time-domain.

8. The method of claim 5, wherein the time-domain profile is measured synchronously based on one or more timing characteristics of the signal.

9. The method of claim 8, wherein the one or more timing characteristics is determined from the signaling protocol of the signal, a symbol time of the signal, a sub-frame of the signal, a frame of the signal, or any combinations thereof.

10. The method of claim 5, wherein the time-domain profile is measured asynchronously from one or more timing characteristics of the signal.

11. The method of claim 1, wherein the signaling protocol used by the one or more transmitters comprises an orthogonal-frequency domain multiplexing protocol.

12. The method of claim 1, wherein the signal generated by the communication device conforms to single-carrier frequency domain multiple access protocol.

13. The method of claim 1, wherein the detecting comprises detecting in a frequency-domain that a power level of the signal exceeds a power level threshold.

14. The method of claim 13, wherein the power level threshold is determined according to an average power level determined by averaging power levels in the frequency-domain or adding an offset to the average power level.

15. The method of claim 13, wherein the detecting comprises measuring a frequency-domain profile of the signal, and detecting the passive intermodulation interference by comparing the power level threshold to the frequency-domain profile.

16. The method of claim 15, wherein the frequency-domain profile is determined according to an occupied bandwidth of the signal, a shape of a power spectral density of the signal, a resource block utilization of the signal, peak to average ratio calculation over a portion or all of a frequency spectrum of the signal, or any combination thereof.

17. The method of claim 1, wherein the signal conditioning is performed by reducing a power level of the signal in one or more portions of the signal in a frequency-domain, spatial filtering of the signal, polarization selection of the signal, or combinations thereof.

18. The method of claim 1, wherein the communication device comprises a portable communication device.

19. The method of claim 1, wherein the communication device comprises a base station.

20. The method of claim 1, wherein the one or more transmitters is part of one or more base stations.

21. The method of claim 1, wherein the one or more transmitters is part of one or more portable communication devices.

22. The method of claim 1, wherein the signal conforms to a common public radio interface (CPRI) protocol.

23. The method of claim 1, wherein the signal originates from multi-input and multi-output (MIMO) antennas.

24. A device, comprising:

an antenna; and

a circuit coupled to the antenna, the circuit facilitating operations including;

receiving, via the antenna, a signal generated by a communication device;

detecting a passive intermodulation interference in the signal, wherein the passive intermodulation interference is generated by one or more transmitters, wherein the passive intermodulation interference is detected by;

determining signal characteristics of the signal;

determining expected signal characteristics associated with a signaling protocol used by the one or more transmitters; and

comparing the signal characteristics of the signal with the expected signal characteristics associated with the signaling protocol;

wherein the one or more transmitters are unassociated with the communication device generating the signal; and

performing signal conditioning on the signal to reduce the passive intermodulation interference.

25. The device of claim 24, wherein the detecting comprises measuring a time-domain profile of the signal, and detecting the passive intermodulation interference by comparing a power level threshold to the time-domain profile.

26. The device of claim 25, wherein the time-domain profile is determined according to a mean calculation of a magnitude and power level of the signal, a median calculation of the magnitude and power level of the signal, a peak calculation of the magnitude and power level of the signal, a peak to average power ratio calculation of the signal, a peak to average ratio magnitude calculation of the signal, or any combination thereof.

27. The device of claim 24, wherein the detecting comprises measuring a frequency-domain profile of the signal, and detecting the passive intermodulation interference by comparing a power level threshold to the frequency-domain profile.

28. The device of claim 27, wherein the frequency-domain profile is determined according to an occupied bandwidth of the signal, a shape of a power spectral density of the signal, a resource block utilization of the signal, peak to average ratio calculation over a portion or all of a frequency spectrum of the signal, or any combination thereof.

29. The device of claim 24, wherein the signal conditioning is performed by reducing a power level of the signal in one or more portions of the signal in a frequency-domain, spatial filtering of the signal, polarization selection of the signal, or combinations thereof.

30. The device of claim 24, wherein the signal conforms to a common public radio interface (CPRI) protocol.

31. The device of claim 24, wherein the signal originates from multi-input and multi-output (MIMO) antennas.

32. A non-transitory, machine-readable storage medium, comprising executable instructions that, when executed by a circuit, facilitate performance of operations, comprising:

receiving, via an antenna, a signal generated by a communication device;

detecting a passive intermodulation interference in the signal, wherein the passive intermodulation interference is generated by one or more transmitters, wherein the passive intermodulation interference is detected by the circuit by;

determining signal characteristics of the signal;

determining expected signal characteristics associated with a signaling protocol used by the one or more transmitters; and

comparing the signal characteristics of the signal with the expected signal characteristics associated with the signaling protocol;

wherein the one or more transmitters are unassociated with the communication device generating the signal; and

performing signal conditioning on the signal to reduce the passive intermodulation interference.

33. The non-transitory, machine-readable storage medium of claim 32, wherein the detecting comprises measuring a time-domain profile of the signal, and detecting the passive intermodulation interference by comparing a power level threshold to the time-domain profile.

34. The non-transitory, machine-readable storage medium of claim 33, wherein the time-domain profile is determined according to a mean calculation of a magnitude and power level of the signal, a median calculation of the magnitude and power level of the signal, a peak calculation of the magnitude and power level of the signal, a peak to average power ratio calculation of the signal, a peak to average ratio magnitude calculation of the signal, or any combination thereof.

35. The non-transitory, machine-readable storage medium of claim 32, wherein the detecting comprises measuring a frequency-domain profile of the signal, and detecting the passive intermodulation interference by comparing a power level threshold to the frequency-domain profile.

36. The non-transitory, machine-readable storage medium of claim 35, wherein the frequency-domain profile is determined according to an occupied bandwidth of the signal, a shape of a power spectral density of the signal, a resource block utilization of the signal, peak to average ratio calculation over a portion or all of a frequency spectrum of the signal, or any combination thereof.

37. The non-transitory, machine-readable storage medium of claim 32, wherein the signal conditioning is performed by reducing a power level of the signal in one or more portions of the signal in a frequency-domain, spatial filtering of the signal, polarization selection of the signal, or combinations thereof.

38. The non-transitory, machine-readable storage medium of claim 32, wherein the signal conforms to a common public radio interface (CPRI) protocol.

39. The non-transitory, machine-readable storage medium of claim 32, wherein the signal originates from multi-input and multi-output (MIMO) antennas.

40. The non-transitory, machine-readable storage medium of claim 32, wherein the detecting comprises detecting the interference in the signal based on a knowledge that one of the one or more transmitters is causing the interference.