Facilitation of passive intermodulation cancellation

Patent metadata

Field	Value
Publication number	US-9768812-B1
Application number	US-201615179427-A
Country	US
Kind code	B1
Filing date	Jun 10, 2016
Priority date	Jun 10, 2016
Publication date	Sep 19, 2017
Grant date	Sep 19, 2017

Abstract

A passive intermodulation detection system is provided to remotely identify passive intermodulation at a base station site and diagnose the type of intermodulation and location of the non-linearity that is the source of the passive intermodulation. The passive intermodulation detection system can generate a test signal in a first band that is transmitted by an antenna. Another antenna can receive a signal in another band, and the passive intermodulation detection system can analyze the received signal to determine whether an intermodulation product due to a non-linearity is present. Based on the type of intermodulation product, period, order, frequency, and etc, the type and location of the non-linearity can be identified and canceled via a passive intermodulation canceling mechanism.

First claim

What is claimed is:

1. A method, comprising:
receiving, by a wireless network device comprising a processor, first signal data related to a signal band, resulting in a first received signal;
filtering, by the wireless network device using a first filter, modeled interference data related to modeled interference products of signals;
generating, by the wireless network device, error output data related to a signal error associated with an actual interference, wherein the error output data further comprises a representation of the first received signal;
processing, by the wireless network device using the first filter, the error output data, resulting in processed error output data; and
receiving, by the wireless network device, second signal data related to the actual interference from the products of the signals; and
cancelling, by the wireless network device, the actual interference in relation to the modeled interference.

2. The method of claim 1 , wherein the signal band comprises constituent signal bands.

3. The method of claim 2 , wherein the first signal data comprises a first downlink signal associated with a first signal band of the constituent signal bands and a second downlink signal associated with a second signal band of the constituent signal bands.

4. The method of claim 3 , wherein the actual interference comprises products of the first signal band and the second signal band.

5. The method of claim 1 , further comprising:
processing, by the wireless network device, an uplink signal associated with the actual interference resulting in the actual interference being canceled.

6. The method of claim 1 , further comprising:
filtering, by the wireless device using a second filter, the modeled interference data, wherein the second filter is a finite impulse response filter.

7. The method of claim 1 , further comprising:
receiving, by the wireless device, returned test signal data related to a returned test signal; and
in response to receiving the returned test signal data, generating location data related to a passive intermodulation source based on a time delay.

8. The method of claim 1 , further comprising:
receiving, by the wireless device, returned test signal data related to returned test signals; and
in response to receiving the returned test signal data, determining a port associated with the interference.

9. A system, comprising:
a processor; and
a memory that stores executable instructions that, when executed by the processor, facilitate performance of operations, comprising:
receiving first signal data associated with a first downlink of a first signal band;
receiving second signal data associated with a second downlink of a second signal band;
filtering, via a first filter, modeled interference data related to a modeled interference associated with the first signal data and the second signal data, resulting in modeled filtered data;
generating error output data related to a signal error associated with the first signal band and the second signal band, wherein the error output data comprises the modeled filtered data;
in response to the generating the error output data, processing, by the first filter, the error output data to be sent as an input to the first filter; and
subtracting the modeled interference from third signal data related to an actual signal.

10. The system of claim 9 , wherein the error output data comprises second interference data related to a second interference.

11. The system of claim 9 , wherein the operations further comprise:
remotely reconfiguring the system, via a software-defined network, resulting in a reconfigured system.

12. The system of claim 11 , wherein the reconfigured system arranges system resources based on an environment factor or a third interference, wherein the third interference appears after an initial configuration.

13. The system of claim 12 , wherein the operations further comprise:
adaptively addressing downlink amplifier nonlinearities to optimize performance.

14. The system of claim 13 wherein the operations further comprise:
based on a ranking associated with a test signal, successively filtering the modeled interference data, related to the modeled interference, resulting in an error reduction.

15. A non-transitory machine-readable storage medium, comprising executable instructions that, when executed by a processor, facilitate performance of operations, comprising:
receiving first signal data related to a signal band, resulting in a first received signal;
filtering, by a first filter, modeled interference data related to a modeled interference of the first received signal, resulting in first filtered data;
generating error output data related to a signal error associated with the modeled interference;
receiving second signal data associated with an actual signal to be input into the first filter; and
in response to the receiving the second signal data, removing the first filtered data from the actual signal.

16. The non-transitory machine-readable storage medium of claim 15 , wherein the operations further comprise:
canceling two intermodulation products of the second signal data simultaneously.

17. The non-transitory machine-readable storage medium of claim 16 , wherein the two intermodulation products are a largest intermodulation products.

18. The non-transitory machine-readable storage medium of claim 15 , wherein the first signal data is ranked based on a signal plus noise to interference ratio.

19. The non-transitory machine-readable storage medium of claim 18 , wherein the first signal data is of a third order.

20. The non-transitory machine-readable storage medium of claim 15 , wherein the first filter is an infinite impulse response filter.

Assignees

• At & T Ip I Lp

Inventors

• Tsui Ernest
• Maxwell Paul
• Kapnadak Vibhav

Classifications

• H04B1/1081

  Reduction of multipath noise (by equalising H04B7/005) · CPC title

• H04B1/109 Primary

  by improving strong signal performance of the receiver when strong unwanted signals are present at the receiver input · CPC title

• H04B17/391 Primary

  Modelling the propagation channel · CPC title

• H04B1/1027 Primary

  assessing signal quality or detecting noise/interference for the received signal · CPC title

• H04B17/3912

  Simulation models, e.g. distribution of spectral power density or received signal strength indicator [RSSI] for a given geographic region · CPC title