Wideband remote unit for distributed antenna system

• US 9,705,609 B2
• Filed: 04/14/2015
• Issued: 07/11/2017
• Est. Priority Date: 04/15/2014
• Status: Active Grant

• Current Assignee: Outdoor Wireless Networks LLC (CommScope Holding Company, Inc.)
• Original Assignee: CommScope Technologies, LLC (CommScope Holding Company, Inc.)
• Inventors: Hanson, Van E., Lange, Keld Knut, Ranson, Christopher G., Kummetz, Thomas
• Primary Examiner(s): Moutaouakil, Mounir
• Application Number:
  US14/686,415
• Publication Number:
  US 20150296527A1
• Time in Patent Office: 819 Days
• CPC Class Codes: H04B 1/525 with means for reducing leakage of transmitter signal into the receiver
• CPC Class Codes: H04B 15/02 Reducing interference from electric apparatus by means located at or near the interfering apparatus
• CPC Class Codes: H04W 88/085 Access point devices with remote components

Abstract

Certain aspects involve a wideband remote unit. The wideband remote unit can include one or more antennas and an analog-to-digital converter (“ADC”). The antenna can receive wideband signals. The wideband signals can include an uplink RF signal and a leaked downlink RF signal. The uplink RF signal can have an uplink signal power at or near a noise level. The leaked downlink RF signal can have a downlink signal power greater than the uplink signal power. The ADC can convert the received wideband signals to digital RF signals representing the uplink signal and the downlink signal. The wideband remote unit can transmit the digital RF signals to a unit of a DAS that is in communication with a base station.

Claims

1. A method comprising:

receiving, via an uplink path of a wideband remote unit of a distributed antenna system, wideband signals comprising an uplink RF signal and a leaked downlink RF signal, the uplink RF signal having an uplink signal power and the leaked downlink RF signal having a downlink signal power greater than the uplink signal power, wherein the leaked downlink RF signal is from a downlink RF signal transmitted by the wideband remote unit;

converting, by the wideband remote unit, the received wideband signals to a first digital RF signal that represents the uplink RF signal and to a second digital RF signal that includes the leaked downlink RF signal; and

transmitting, in the uplink path from the wideband remote unit, the first digital RF signal and the second digital RF signal to a unit of the distributed antenna system in communication with a base station;

wherein the uplink path of the wideband remote unit is configured with a dynamic range having a minimum value and a maximum value suitable to digitize both the uplink RF signal and the leaked downlink RF signal.

2. The method of claim 1, further comprising providing, via a downlink path of the wideband remote unit, the downlink RF signal to an antenna that transmits the downlink RF signal, wherein the downlink path is coupled via a splitter-combiner to the antenna.

3. The method of claim 2, further comprising:

transmitting, by the unit, an uplink signal to the base station, wherein the uplink signal corresponds to the first digital RF signal; and

mitigating, by the unit, the second digital RF signal corresponding to the leaked downlink RF signal.

4. The method of claim 3, wherein mitigating the second digital RF signal comprises at least one of:

filtering the second digital RF signal from a combined uplink signal generated from the first digital RF signal;

cancelling the second digital RF signal from the combined uplink signal;

or

attenuating the second digital RF signal.

5. The method of claim 3, wherein mitigating the second digital RF signal comprises:

correlating a downlink signal traversing the downlink path with a signal component traversing the uplink path;

generating a cancellation signal corresponding to the second digital RF signal based on correlating the downlink signal traversing the downlink path with the signal component traversing the uplink path; and

combining the cancellation signal with a combined uplink signal generated from the first digital RF signal.

6. The method of claim 1, wherein the uplink signal power is at a thermal noise level associated with the wideband remote unit, wherein the method further comprises configuring an analog-to-digital converter of the wideband remote unit with a dynamic range having a minimum value corresponding to the thermal noise level and a maximum value corresponding to the downlink signal power.

7. The method of claim 6, further comprising configuring the dynamic range based on a data rate for a digital communication link between the wideband remote unit and the unit.

8. The method of claim 1, wherein the downlink RF signal comprises a first multiple-input, multiple-output data stream received from the unit, wherein the method further comprises:

transmitting, by an additional wideband remote unit of the distributed antenna system, an additional downlink RF signal comprising a second multiple-input, multiple-output data stream;

receiving, by the additional wideband remote unit, an additional leaked downlink RF signal, wherein the additional leaked downlink RF signal is obtained from the additional downlink RF signal transmitted by the additional wideband remote unit;

transmitting, by the additional wideband remote unit, a third digital RF signal to the unit, wherein the third digital RF signal is generated from the additional leaked downlink RF signal; and

mitigating, by the unit, the second digital RF signal and the third digital RF signal.

9. A wideband remote unit comprising:

an antenna configured for receiving wideband signals comprising an uplink RF signal and a leaked downlink RF signal, the uplink RF signal having an uplink signal power and the leaked downlink RF signal having a downlink signal power greater than the uplink signal power, wherein the leaked downlink RF signal is from a downlink RF signal transmitted by the wideband remote unit; and

an analog-to-digital converter in an uplink path of the wideband remote unit, the analog-to-digital converter configured for converting the received wideband signals to a first digital RF signal that represents the uplink signal and to a second digital RF signal that includes the leaked downlink signal,

wherein the wideband remote unit is configured for transmitting from the wideband remote unit through the uplink path the first and second digital RF signals to a unit of a distributed antenna system that is communicatively coupled to a base station;

wherein the uplink path of the wideband remote unit is configured with a dynamic range having a minimum value and a maximum value suitable to digitize both the uplink RF signal and the leaked downlink RF signal.

10. The wideband remote unit of claim 9, further comprising a downlink path configured for providing the downlink RF signal to the antenna and an uplink path comprising the analog-to-digital converter, wherein the uplink path is communicatively coupled to the downlink path via a splitter-combiner of the wideband remote unit.

11. The wideband remote unit of claim 9, wherein the analog-to-digital converter of the wideband remote unit has a dynamic range having a minimum value corresponding to a thermal noise level associated with the wideband remote unit and a maximum value corresponding to the downlink signal power.

12. The wideband remote unit of claim 11, wherein the dynamic range is based on a data rate for a digital communication link between the wideband remote unit and the unit.

13. The wideband remote unit of claim 12, wherein the analog-to-digital converter of the wideband remote unit has a sampling rate corresponding to a maximum RF frequency of the wideband signals and the data rate for the digital communication link.

14. A distributed antenna system comprising:

a wideband remote unit configured for;

receiving wideband signals comprising an uplink RF signal and a leaked downlink RF signal, the uplink RF signal having an uplink signal power and the leaked downlink RF signal having a downlink signal power greater than the uplink signal power, wherein the leaked downlink RF signal is from a downlink RF signal transmitted by the wideband remote unit, converting in an uplink path of the wideband remote unit the received wideband signals to a first digital RF signal that represents the uplink signal and a second digital RF signal that includes the leaked downlink signal, and

transmitting from the wideband remote unit through the uplink path the first and second digital RF signals to a unit; and

the unit configured for;

transmitting an uplink signal to a base station, wherein the uplink signal corresponds to the first digital RF signal; and

mitigating the second digital RF signal corresponding to the leaked downlink RF signal;

wherein the uplink path of the wideband remote unit is configured with a dynamic range having a minimum value and a maximum value suitable to digitize both the uplink RF signal and the leaked downlink RF signal.

15. The distributed antenna system of claim 14, wherein the wideband remote unit comprises a downlink path configured for providing the downlink RF signal to an antenna of the wideband remote unit, wherein the downlink path is coupled via a splitter-combiner to the antenna and an uplink path configured for receiving the wideband signals.

16. The distributed antenna system of claim 14, wherein the unit comprises a non-duplexer isolation sub-system configured for mitigating the second digital RF signal.

17. The distributed antenna system of claim 14, wherein the wideband remote unit comprises an analog-to-digital converter with a dynamic range having a minimum value corresponding to a thermal noise level associated with the wideband remote unit and a maximum value corresponding to the downlink signal power.

18. The distributed antenna system of claim 17, wherein the dynamic range is based on a data rate for a digital communication link between the wideband remote unit and the unit.

19. The distributed antenna system of claim 18, wherein the analog-to-digital converter of the wideband remote unit has a sampling rate corresponding to a maximum RF frequency of the wideband signals and the data rate for the digital communication link.

20. The distributed antenna system of claim 14, wherein the downlink RF signal comprises a first multiple-input, multiple-output data stream received from the unit, wherein the distributed antenna system further comprises:

an additional wideband remote unit configured for;

transmitting an additional downlink RF signal comprising a second multiple-input, multiple-output data stream,

receiving an additional leaked downlink RF signal, wherein the additional leaked downlink RF signal is obtained from the additional downlink RF signal transmitted by the additional wideband remote unit, and

transmitting a third digital RF signal to the unit, wherein the third digital RF signal is generated from the additional leaked downlink RF signal,

wherein the unit is further configured for mitigating the third digital RF signal.