Distributed antenna system for MIMO signals

Patent metadata

Field	Value
Publication number	US-10700754-B2
Application number	US-201715727420-A
Country	US
Kind code	B2
Filing date	Oct 6, 2017
Priority date	Nov 30, 2001
Publication date	Jun 30, 2020
Grant date	Jun 30, 2020

Abstract

A distributed antenna system (DAS) includes a master unit; a plurality of remote units communicatively coupled with the master unit and distributed to provide coverage within a service area, each of the remote units remotely located from the master unit and other remote units; a coupler element coupled to receive a plurality of MIMO signals, the MIMO signals including first and second MIMO signals, the coupler element configured to: introduce a phase shift in a first portion of the first MIMO signal to generate a first phase shifted portion of the first MIMO signal; combine the first phase shifted portion with a second portion of the second MIMO signal to generate a combined MIMO signal; and present the combined MIMO signal at a first output port of the coupler element; at least one antenna coupled with each remote unit and configured to receive the combined MIMO signal for transmission.

First claim

What is claimed is:

1. A distributed antenna system comprising:
at least one master unit;
a plurality of remote units communicatively coupled with the at least one master unit and distributed to provide coverage within a service area, each of the plurality of remote units remotely located from the at least one master unit and other remote units of the plurality of remote units;
a coupler element coupled to receive a plurality of multiple-input and multiple-output (MIMO) signals, the plurality of MIMO signals including at least a first MIMO signal and a second MIMO signal, the coupler element configured to:
introduce a phase shift in a first portion of the first MIMO signal to generate a first phase shifted portion of the first MIMO signal;
combine the first phase shifted portion with a second portion of the second MIMO signal to generate a combined MIMO signal; and
present the combined MIMO signal at a first output port of the coupler element;

at least one antenna coupled with each of the plurality of remote units and configured to receive the combined MIMO signal for transmission.

2. The distributed antenna system of claim 1 , wherein the first output port of the coupler element is coupled with the at least one master unit and configured to present the combined MIMO signal to the master unit for distribution to the at least one antenna.

3. The distributed antenna system of claim 2 , wherein the at least one master unit is a MIMO master unit.

4. The distributed antenna system of claim 2 , wherein the at least one master unit is a single-input and single-output (SISO) master unit.

5. The distributed antenna system of claim 1 , wherein the coupler element is configured to:
introduce a phase shift in a second portion of the second MIMO signal to generate a second phase shifted portion of the second MIMO signal;
combine the second phase shifted portion with a third portion of the first MIMO signal to generate a second combined MIMO signal; and
present the second combined MIMO signal at a second output port of the coupler element;
wherein one or more of the at least one antenna is configured to receive the second combined MIMO signal for transmission.

6. The distributed antenna system of claim 5 , wherein the first output port of the coupler unit is coupled with the at least one master unit and configured to present the combined MIMO signal to the master unit for distribution to antennas for transmission; and
wherein the second output port of the coupler unit is coupled with the at least one master unit and configured to present the second combined MIMO signal to the master unit for distribution to antennas for transmission.

7. The distributed antenna system of claim 6 , wherein the at least one master unit is a MIMO master unit.

8. The distributed antenna system of claim 7 , wherein the MIMO master unit is coupled with a plurality of MIMO remote units each coupled with a plurality of antennas, the MIMO master unit configured to direct the combined MIMO signal of both the first output port and the second output port to a MIMO remote unit, the MIMO remote unit configured to direct the combined MIMO signal of the first output port to one antenna and the combined MIMO signal of the second port to another antenna.

9. The distributed antenna system of claim 5 , wherein signals of the first output port are coupled with a first master unit and the signals of the second output port are coupled with a second master unit, wherein the first master unit and the second master unit are coupled with a plurality of single-input and single-output (SISO) remote units and configured to:
direct the combined MIMO signal of the first output port to at least one SISO remote unit; and
direct the second combined MIMO signal of the second output port to another SISO remote unit.

10. The distributed antenna system of claim 1 , wherein the master unit is configured to:
couple with a source of MIMO signals; and
direct the MIMO signals to the remote units and antennas, the coupler element being coupled between the remote unit and a respective antenna for presenting the combined MIMO signal from the first outlet port to the antenna.

11. The distributed antenna system of claim 2 , wherein at least one of the plurality of remote units is a MIMO remote unit with a plurality of antennas;
wherein the master unit is configured to:
couple with a source of MIMO signals to direct MIMO signals to the MIMO remote unit and antennas, the coupler element being coupled between the MIMO remote unit and respective antennas;
present the combined MIMO signal from the first outlet port to one antenna; and
present the second combined MIMO signal from the second outlet port to another antenna.

12. The distributed antenna system of claim 1 , wherein the remote unit is coupled with the master unit over at least one of an optical link or an RF link.

13. The distributed antenna system of claim 1 , wherein the plurality of remote units are coupled with the at least one master unit via optical fibers.

14. The distributed antenna system of claim 1 , wherein the coupler element is a 90° 3 dB hybrid coupler.

15. The distributed antenna system of claim 1 , wherein the coupler element introduces an orthogonal phase shift to a portion of the MIMO signal.

16. A distributed antenna system comprising:
at least one master unit;
a plurality of remote units communicatively coupled with the at least one master unit and distributed to provide coverage within a service area, each of the plurality of remote units remotely located from the at least one master unit and other remote units of the plurality of remote units;
at least one antenna coupled with each of the remote units and configured to transmit signals from the remote unit;
a coupler element operatively coupled with the master unit and configured to receive, from a signal source, a plurality of multiple-input and multiple-output (MIMO) signals including at least a first MIMO signal and a second MIMO signal of the plurality of MIMO signals, the coupler element configured to:
introduce a phase shift in a first portion of at least the first MIMO signal to generate a first phase shifted portion of the first MIMO signal;
combine the first phase shifted portion with a second portion of the second MIMO signal to generate a combined MIMO signal;
present the combined MIMO signal at a first output port of the coupler element;

the master unit configured to receive the combined MIMO signal from the first output port;
the remote units configured to receive the combined MIMO signal portions of the first output port from the master unit for transmission.

17. The distributed antenna system of claim 16 , wherein the coupler element is configured to:
introduce a phase shift in a second portion of at least the second MIMO signal to generate a second phase shifted portion of the second MIMO signal;
combine the second phase shifted portion with a third portion of the first MIMO signal to generate a second combined MIMO signal;
present the second combined MIMO signal at a second output port of the coupler element;
wherein the master unit is configured to introduce the second combined MIMO signal from the second output port, the remote units and respective antennas configured to receive the second combined MIMO signal of the second output port from the master unit for transmission.

18. The distributed antenna system of 17 , wherein the remote units are MIMO remote units, the MIMO remote units configured to receive the combined MIMO signal portions of b

Assignees

• Andrew Wireless Systems Gmbh

Inventors

• Tarlazzi Luigi
• Brighenti Samuele
• Faccin Pier

Classifications

• H04W88/085

  Access point devices with remote components · CPC title

• H04J14/0247

  Sharing one wavelength for at least a group of ONUs · CPC title

• H04B7/0682 Primary

  using phase diversity (e.g. phase sweeping) · CPC title

• H04B7/0413

  MIMO systems · CPC title

• H04B7/024

  Co-operative use of antennas of several sites, e.g. in co-ordinated multipoint or co-operative multiple-input multiple-output [MIMO] systems · CPC title