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