Facilitation of passive intermodulation cancellation

• US 9,768,812 B1
• Filed: 06/10/2016
• Issued: 09/19/2017
• Est. Priority Date: 06/10/2016
• Status: Active Grant

• Current Assignee: AT&T Intellectual Property I LP (AT&T, Inc.)
• Original Assignee: AT&T Intellectual Property I LP (AT&T, Inc.)
• Inventors: Tsui, Ernest, Maxwell, Paul, Kapnadak, Vibhav
• Primary Examiner(s): TAYONG, HELENE E
• Application Number:
  US15/179,427
• Time in Patent Office: 466 Days
• Field of Search: 375227
• CPC Class Codes: H04B 1/109 by improving strong signal performance of the receiver when strong unwanted signals are present at the receiver input
• CPC Class Codes: H04B 17/0085 using test signal generators
• CPC Class Codes: H04B 17/391 Modelling the propagation channel
• CPC Class Codes: H04B 17/3912 Simulation models, e.g. distribution of spectral power density or received signal strength indicator [RSSI] for a given geographic region

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.

Claims

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.