Distributed antenna system for MIMO signals

• US 9,979,443 B2
• Filed: 03/20/2017
• Issued: 05/22/2018
• Est. Priority Date: 10/01/2010
• Status: Active Grant

• Current Assignee: CommScope Technologies, LLC (CommScope Holding Company, Inc.)
• Original Assignee: CommScope Technologies, LLC (CommScope Holding Company, Inc.)
• Inventors: Schmid, Peter, Gunzner, Peter, Langer, Harald, Eisenwinter, Stefan, Fabbri, Marianna, Braz, Oliver, Fabbri, Enrico Maria, Brighenti, Samuele, Parrucci, Marco, Mini, Massimiliano, Kummetz, Thomas
• Primary Examiner(s): Vanderpuye, Ken N
• Assistant Examiner(s): Sandhu, Amritbir
• Application Number:
  US15/464,014
• Publication Number:
  US 20170195015A1
• Time in Patent Office: 428 Days
• CPC Class Codes: H04B 1/0096 where a full band is frequency converted into another full band
• CPC Class Codes: H04B 7/0413 MIMO systems

Abstract

A distributed antenna system, comprising: master unit configured to: receive MIMO channel signals at MIMO frequency from signal source, MIMO channel signals including first and second MIMO channel signals; generate LO signal; frequency convert first and/or second MIMO channel signal from MIMO frequency to different frequency close to first legacy service frequency band using the LO signal; combine first MIMO channel signal, second MIMO channel signal, and LO signal for transmission; optical link operably coupled with master unit; unit communicatively coupled with master unit via optical link for transceiving first second MIMO channel signal, unit including band processing circuitry configured to process first and second MIMO channel signal; conversion circuitry configured to receive converted MIMO channel signal and to frequency convert converted MIMO channel signal from frequency close to first legacy service frequency band back to MIMO frequency for transmission over antenna.

Claims

1. A distributed antenna system, comprising:

a master unit configured to;

receive at least one set of multiple input multiple output (MIMO) channel signals at an original MIMO frequency from at least one signal source, at least one set of the MIMO channel signals including at least a first MIMO channel signal and a second MIMO channel signal;

generate a local oscillator (LO) signal;

frequency convert the at least one of the first MIMO channel signal and the second MIMO channel signal from an original MIMO frequency to a different frequency different from a first legacy service frequency band using the LO signal;

combine the first MIMO channel signal, the second MIMO channel signal, and the LO signal for transmission;

an optical link operably coupled with the master unit;

a remote unit communicatively coupled with the master unit via the optical link for transceiving the first MIMO channel signal and the second MIMO channel signal, the unit including band processing circuitry configured to process the at least one of the first MIMO channel signal and the second MIMO channel signal;

conversion circuitry configured to receive the at least one converted MIMO channel signal and to frequency convert the at least one converted MIMO channel signal from the different frequency different from the first legacy service frequency band back to the original MIMO frequency for transmission over one or more antennas.

2. The distributed antenna system of claim 1, wherein the conversion circuitry is configured to receive the LO signal from the remote unit and use the LO signal to frequency convert the at least one of the first MIMO channel signal and the second MIMO channel signal from the different frequency different from the first legacy service frequency band back to the original MIMO frequency.

3. The distributed antenna system of claim 1, the master unit including circuitry for using the LO signal to generate other frequency signals for use in converting at least a second one of the first MIMO channel signal and the second MIMO channel signal to another different frequency close to different from the first legacy service frequency band from the original MIMO frequency.

4. The distributed antenna system of claim 1, wherein the master unit is configured to frequency convert both the first MIMO channel signal and the second MIMO channel signal to different frequencies, the master unit further configured to frequency convert the first MIMO channel signal to a frequency that is different from a frequency of the second MIMO channel signal.

5. The distributed antenna system of claim 4, wherein the conversion circuitry is configured to frequency convert all of the MIMO channel signals back to the original MIMO frequency for transmission over the one or more antennas.

6. The distributed antenna system of claim 1, wherein:

the master unit is further configured to;

receive at least one non-MIMO signal that has a frequency in the first legacy service frequency band;

process the at least one converted MIMO channel signal and the at least one non-MIMO signal using the band processing circuit component; and

combine the at least one non-MIMO signal in the first legacy service frequency band along with the first MIMO channel signal, the second MIMO channel signal, and the LO signal for transmission; and

the band processing circuitry of the remote unit is configured to process together the at least one non-MIMO signal in the first legacy service frequency band and the at least one of the first MIMO channel signal and the second MIMO channel signal.

7. The distributed antenna system of claim 1, wherein the optical link includes at least one of the following:

at least one fiber-optic cable for transceiving both uplink signals and downlink signals between the remote unit and the master unit;

or

at least two fiber optic cables with one fiber-optic cable for transceiving uplink signals between the remote unit and the master unit and another fiber-optic cable for transceiving downlink signals between the remote unit and the master unit.

8. The distributed antenna system of claim 1, further comprising at least one remote unit in communication with the master unit via the optical link, the conversion circuitry located in the at least one remote unit.

9. The distributed antenna system of claim 1, further comprising at least one extension unit in communication with the at least one remote unit, the conversion circuitry located in the at least one extension unit.

10. The distributed antenna system of claim 1, wherein:

the first legacy service frequency band is lower in frequency than the original MIMO frequency of the at least one set of MIMO channel signals; and

the master unit is configured to frequency convert the at least one of the first MIMO channel signal and the second MIMO channel signal from the original MIMO frequency to a lower different frequency that is different from the first legacy service frequency band.

11. The distributed antenna system of claim 1, wherein:

the first legacy service frequency band is higher in frequency than the original MIMO frequency of the at least one set of MIMO channel signals; and

the master unit configured to frequency convert the at least one of the first MIMO channel signal and the second MIMO channel signal from the original MIMO frequency to a higher different frequency that is different from the first legacy service frequency band.

12. The distributed antenna system of claim 1, wherein the master unit is further configured to:

receive at least one additional set of MIMO channel signals at another original MIMO frequency different from the original MIMO frequency of the at least one set of MIMO signals;

frequency convert at least one of first and second MIMO channel signals of the additional set of MIMO channel signals to another different frequency different from the first legacy service frequency band from the another original MIMO frequency; and

combine the at least one addition set of MIMO channel signals for transmission.

13. The distributed antenna system of claim 12, further comprising:

a plurality of extension units coupled to at least one remote unit, each extension unit including conversion circuitry configured to frequency convert the at least one of the first and the second converted MIMO channel signals of the at least one additional set from the frequency different from the first legacy service frequency band back to the another original MIMO frequency for transmission over the one or more antennas.

14. The distributed antenna system of claim 12, wherein the master unit is further configured to:

frequency convert the at least one of the first MIMO channel signal and the second MIMO channel signal of the additional set of MIMO channel signals to another different frequency that is different from the original MIMO frequency of the at least one set of MIMO channels signals; and

combine the at least one set of MIMO channel signals for transmission.

15. The distributed antenna system of claim 1, wherein:

at least one of the first MIMO channel signal and the second MIMO channel signal is maintained at the original MIMO frequency; and

the remote unit is configured to transmit at least one of the first MIMO channel signal and the second MIMO channel signal at the original MIMO frequency over the one or more antennas.

16. A distributed antenna system, comprising:

a master unit configured to;

receive a plurality of sets of multiple input multiple output (MIMO) channel signals at respective original first and second MIMO frequencies, each set of the MIMO channel signals including at least a first MIMO channel signal and a second MIMO channel signal;

generate a local oscillator (LO) signal;

frequency convert the at least one of the first MIMO channel signals from the original first MIMO frequency to a first different frequency different from a first legacy service frequency band using the LO signal;

frequency convert the at least one of the second MIMO channel signals from the original second MIMO frequency to a second different frequency different from a second legacy service frequency band based on the LO signal;

combine the at least one of the first MIMO channel signals, the at least one of the second MIMO channel signals, and the LO signal for transmission;

an optical link operably coupled with the master unit;

at least one remote unit communicatively coupled with the master unit via the optical link for transceiving the plurality of sets of MIMO channel signals between the remote unit and the master unit, the at least one remote unit including;

a first band processing circuit component configured to process the at least one converted first MIMO channel signal; and

a second band processing circuit component configured to process the at least one converted second MIMO channel signal;

a plurality of conversion circuits, at least one conversion circuit configured to;

receive the at least one converted first MIMO channel signal;

frequency convert the at least one converted first MIMO channel signal from the first different frequency different from the first legacy service frequency band and back to the first MIMO frequency for transmission over one or more antennas;

receive the at least one converted second MIMO channel signal;

frequency convert the at least one converted second MIMO frequency channel signal from the second different frequency different from the second legacy service frequency band and back to the second MIMO frequency for transmission over the one or more antennas.

17. The distributed antenna system of claim 16, wherein the at least one conversion circuit is configured to:

receive the LO signal from the remote unit; and

use the LO signal to frequency convert the at least one converted first MIMO channel signal from the first different frequency different from the first legacy service frequency band and back to the first MIMO frequency for transmission over the one or more antennas.

18. The distributed antenna system of claim 16, wherein the master unit is configured to:

use the LO signal to generate a second LO signal for use in converting the original second MIMO frequency to the second different frequency different from the second legacy service frequency band.

19. The distributed antenna system of claim 18, wherein the at least one conversion circuit is configured to:

receive the at least one LO signal from the remote unit; and

use the LO signal to frequency convert the at least one converted first MIMO channel signal from the first different frequency different from the first legacy service frequency band and back to the first MIMO frequency for transmission over the one or more antennas;

use the second LO signal to frequency convert the at least one converted second MIMO channel signal from the second different frequency different from the second legacy service frequency band and back to the second MIMO frequency for transmission over the one or more antennas.

20. The distributed antenna system of claim 16, wherein:

the master unit is further configured to;

receive a plurality of non-MIMO signals that have original frequencies in at least the first legacy service frequency band and the second legacy service frequency band;

process the plurality of non-MIMO signals using the band processing circuit component;

combine the plurality of non-MIMO signals in the at least the first legacy service frequency band and the second legacy service frequency band along with the at least one of the first MIMO channel signals, the at least one of the second MIMO channel signals, and the LO signal for transmission;

the first band processing circuit component of the remote unit configured to process together the plurality of non-MIMO signals in the at least the first legacy service frequency band and the at least one converted first MIMO channel signal;

the second band processing circuit component of the remote unit configured to process together the plurality of non-MIMO signals in the at least the second legacy service frequency band and the at least one converted second MIMO channel signal.