BROADBAND DISTRIBUTED ANTENNA SYSTEM WITH NON-DUPLEXER ISOLATOR SUB-SYSTEM

• US 20150288414A1
• Filed: 06/17/2015
• Published: 10/08/2015
• Est. Priority Date: 06/01/2011
• Status: Active Grant

• Current Assignee: CommScope Technologies, LLC (CommScope Holding Company, Inc.)
• Original Assignee: CommScope Technologies, LLC (CommScope Holding Company, Inc.)
• Inventors: Morrison, Charles B., McAllister, Donald R., Phillips, Fred W., Ranson, Christopher G., Hanson, Van E., Kummetz, Thomas, Maca, Gregory Allan
• Granted Patent: US 9,859,946 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H01Q 1/246 specially adapted for base stations
• CPC Class Codes: H01Q 1/525 between emitting and receiving antennas
• CPC Class Codes: H04B 1/0053 with common antenna for more than one band
• CPC Class Codes: H04B 1/44 Transmit/receive switching
• CPC Class Codes: H04B 1/525 with means for reducing leakage of transmitter signal into the receiver
• CPC Class Codes: H04B 10/25754 Star network topology
• CPC Class Codes: H04W 88/085 Access point devices with remote components

Abstract

Certain aspects and aspects of the present invention are directed to a distributed antenna system having a downlink communication path, an uplink communication path, and a non-duplexer isolator sub-system. The downlink communication path can communicatively couple a transmit antenna to a base station. The uplink communication path can communicatively couple a receive antenna to the base station. In one aspect, the non-duplexer isolator sub-system can be electronically configured for isolating uplink signals traversing the uplink communication path from downlink signals. In another aspect, a non-duplexer isolator sub-system can be configurable in one or more mechanical steps selecting a frequency response. In another aspect, a non-duplexer isolator sub-system can include an active mitigation sub-system.

Claims

1. A method comprising:

receiving a downlink reference signal from a downlink path;

generating, by a non-duplexer isolator sub-system, a mitigation signal from the downlink reference signal by mitigating uplink frequency components in the downlink reference signal; and

mitigating, by the non-duplexer isolator sub-system, downlink frequency components in an uplink signal traversing an uplink path by combining the mitigation signal with the uplink signal.

2. The method of claim 1, wherein mitigating the uplink frequency components comprises generating an additional mitigation signal with the uplink frequency components and combining the additional mitigation signal with the downlink reference signal.

3. The method of claim 2, wherein generating the additional mitigation signal comprises:

receiving an additional downlink reference signal from the downlink path; and

mitigating downlink frequency components in the additional downlink reference signal to obtain the additional mitigation signal.

4. The method of claim 3, wherein the additional downlink reference signal is a digital downlink signal received from a point in the downlink path prior to a digital-to-analog converter and wherein mitigating the downlink frequency components comprises digitally filtering the additional downlink reference signal to attenuate the downlink frequency components.

5. The method of claim 1, further comprising:

generating a nonlinear distortion mitigation signal; and

mitigating nonlinear distortion in the uplink signal by combining the nonlinear distortion mitigation signal with the uplink signal.

6. The method of claim 5, further comprising:

generating an additional nonlinear distortion mitigation signal; and

mitigating nonlinear distortion in the downlink reference signal prior to generating the mitigation signal from the downlink reference signal, wherein the nonlinear distortion in the downlink reference signal is mitigated by combining the additional nonlinear distortion mitigation signal with the downlink reference signal.

7. A non-duplexer isolator sub-system comprising:

a mitigation sub-system configured for;

receiving a downlink reference signal from a downlink path,

generating a mitigation signal by mitigating uplink frequency components in the downlink reference signal, and

mitigating downlink frequency components in an uplink signal traversing an uplink path by combining the mitigation signal with the uplink signal.

8. The non-duplexer isolator sub-system of claim 7, wherein the active mitigation sub-system comprises:

a first digital summer communicatively coupled to the downlink path and configured for mitigating the uplink frequency components in the downlink reference signal; and

a second digital summer included in the uplink path and communicatively coupled to the first digital summer, wherein the second digital summer is configured for combining the mitigation signal with the uplink signal.

9. The non-duplexer isolator sub-system of claim 8, wherein the active mitigation sub-system further comprises a digital filter coupled between the downlink path and the first digital summer, wherein the digital filter is configured for generating an additional mitigation signal having the uplink frequency components and the first digital summer is configured for combining the additional mitigation signal with the downlink reference signal.

10. The non-duplexer isolator sub-system of claim 9, wherein the digital filter is configured for generating the additional mitigation signal by mitigating downlink frequency components in a digital downlink reference signal received from the downlink path.

11. The non-duplexer isolator sub-system of claim 7, wherein the active mitigation sub-system is further configured for:

generating a nonlinear distortion mitigation signal; and

mitigating nonlinear distortion in the uplink signal by combining the nonlinear distortion mitigation signal with the uplink signal.

12. The non-duplexer isolator sub-system of claim 11, wherein the active mitigation sub-system is further configured for:

generating an additional nonlinear distortion mitigation signal; and

mitigating nonlinear distortion in the downlink reference signal prior to generating the mitigation signal from the downlink reference signal, wherein the nonlinear distortion in the downlink reference signal is mitigated by combining the additional nonlinear distortion mitigation signal with the downlink reference signal.

13. The non-duplexer isolator sub-system of claim 12, wherein the active mitigation sub-system comprises:

a plurality of digital filters configured for generating the mitigation signal, the nonlinear distortion mitigation signal, and the additional nonlinear distortion mitigation signal;

a plurality of digital summers configured for combining the mitigation signal with the uplink signal, combining the additional nonlinear distortion mitigation signal with the downlink reference signal, and combining the nonlinear distortion mitigation signal with the uplink signal.

14. The non-duplexer isolator sub-system of claim 13, further comprising a reference path between a point on the downlink path and a digital summer configured for combining the mitigation signal with the uplink signal, wherein the reference path comprises down-conversion circuitry and an analog-to-digital converter configured for generating the downlink reference signal from an analog downlink signal sampled from the downlink path.

15. A non-duplexer isolator sub-system comprising:

a mitigation sub-system configured for;

generating a mitigation signal from a downlink reference signal received from a downlink path,

generating a nonlinear distortion mitigation signal from a digital downlink reference signal received from the downlink path, and

mitigating downlink frequency components and nonlinear distortion in an uplink signal traversing an uplink path by combining the nonlinear distortion mitigation signal with the uplink signal.

16. The non-duplexer isolator sub-system of claim 15, wherein the active mitigation sub-system is further configured for:

generating an additional nonlinear distortion mitigation signal; and

mitigating nonlinear distortion in the downlink reference signal prior to generating the mitigation signal by combining the additional nonlinear distortion mitigation signal with the downlink reference signal.

17. The non-duplexer isolator sub-system of claim 15, wherein the active mitigation sub-system is configured for generating the mitigation signal by mitigating uplink frequency components in the downlink reference signal.

18. The non-duplexer isolator sub-system of claim 15, wherein the active mitigation sub-system comprises:

a first digital filter communicatively coupled to the downlink path and configured for inverting the downlink reference signal to generate the mitigation signal;

a first digital summer included in the uplink path and configured for combining the mitigation signal with the uplink signal;

a second digital filter communicatively coupled to the downlink path and configured for generating the nonlinear distortion mitigation signal;

a second digital summer included in the uplink path and configured for combining the nonlinear distortion mitigation signal with the uplink signal.

19. The non-duplexer isolator sub-system of claim 18, wherein the active mitigation sub-system further comprises:

a third digital filter configured for generating an additional nonlinear distortion mitigation signal; and

a third digital summer included in a signal path from the downlink path to the first digital filter and configured for combining the additional nonlinear distortion mitigation signal with the downlink reference signal.

20. The non-duplexer isolator sub-system of claim 18, wherein the active mitigation sub-system further comprises a reference path between a point on the downlink path and the first digital summer, wherein the reference path comprises down-conversion circuitry and an analog-to-digital converter configured for generating the downlink reference signal from an analog downlink signal sampled from the downlink path.