TRANSCEIVER AND A REPEATER

• US 20120003926A1
• Filed: 04/29/2009
• Published: 01/05/2012
• Est. Priority Date: 03/19/2009
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Coldrey, Mikael, Frenger, Pal, Persson, Patrik
• Granted Patent: US 9,083,421 B2
• Time in Patent Office: Days
• US Class Current: 455/9
• CPC Class Codes: H04B 7/0632 Channel quality parameters, e.g. channel quality indicator [CQI]
• CPC Class Codes: H04B 7/15557 Selecting relay station operation mode, e.g. between amplify and forward mode, decode and forward mode or FDD - and TDD mode
• CPC Class Codes: H04B 7/15592 Adapting at the relay station communication parameters for supporting cooperative relaying, i.e. transmission of the same data via direct - and relayed path cooperative diversity H04B7/024

Abstract

The invention discloses a transceiver (210, 215; 305, 310, 320, 330) for use in a cellular communications system (200, 300), arranged to communicate with at least one other transceiver in the system by means of technology for Multiple Input Multiple Output, MIMO. The transceiver is also arranged to control the function of a repeater (206, 207, 208, 209; 340) which is arranged to forward communication between the transceiver and said at least one other transceiver, said control being carried out as a result of measured performance parameters of the communication between the transceiver and said at least one other transceiver. In one embodiment, the function in the repeater (206, 207, 208, 209; 340) which the transceiver is arranged to control comprises activation and deactivation of the repeater.

Claims

1. A transceiver for use in a cellular communications system, the transceiver being arranged to communicate with at least one other transceiver in said system by means of technology for Multiple Input Multiple Output, MIMO, the transceiver being also arranged to control a repeater arranged to forward communication between the transceiver and said at least one other transceiver, said control being carried out as a result of measured performance parameters of the communication between the transceiver and said at least one other transceiver.

2. The transceiver of claim 1, wherein the transceiver is operable to activate and deactivate the repeater based on the measured performance parameters.

3. The transceiver of claim 1, wherein the transceiver is operable to control the amplitude and/or phase of a signal transmitted by the repeater that corresponds to a signal transmitted by the transceiver.

4. The transceiver of claim 1, in which said measured performance parameters are measured by the transceiver itself.

5. The transceiver of claim 1, in which said measured performance parameters are measured by said at least one other transceiver and reported to the transceiver.

6. The transceiver of claim 1, in which the measured performance parameters comprise the rank of one or more MIMO channel and/or the CQI of one or more MIMO channels.

7. The transceiver of claim 1, wherein the transceiver is a controlling node for a cell in the system.

8. The transceiver of claim 7, wherein the transceiver is an LTE eNodeB.

9. The transceiver of claim 1, wherein the transceiver is a user terminal for the system.

10. A repeater for use in a cellular communications system, the repeater being arranged to forward communications between a first and a second transceiver in said system, the repeater being characterized in that it is arranged to have its function be remote controlled from an external source.

11. The repeater of claim 10, in which said external source comprises at least one of said transceivers.

12. The repeater of claim 10, in which said function which is arranged to be remote controlled comprises activation and deactivation of the repeater.

13. The repeater of claim 10, in which said function which is arranged to be remote controlled comprises the amplitude and/or the phase of a forwarded signal.

14. The repeater of claim 10, in which the external source is a controlling node for a cell in the system.

15. The repeater of claim 14, in which the external source is an LTE eNodeB.

16. The repeater of claim 10, in which the external source is a user terminal in the system.

17. A cellular communications system comprising at least a first cell with a first transceiver which is arranged to communicate with other transceivers in the cell by means of technology for Multiple Input Multiple Output, MIMO, wherein the first transceiver is arranged to control the function of a repeater which is arranged to forward communication between the first transceiver and at least one of said other transceivers in the cell.

18. The system of claim 17, in which said function in the repeater which the first transceiver is arranged to control comprises activation and deactivation of the repeater.

19. The system of claim 17, in which said function in the repeater which the first transceiver is arranged to control comprises the amplitude and/or the phase of a forwarded signal.

20. The system of claim 17, in which said measured performance parameters are measured by the first transceiver itself.

21. The system of claim 17, in which said measured performance parameters are measured by said at least one other transceiver and reported to the first transceiver.

22. The system of claim 17, in which the measured performance parameters comprise the rank of one or more MIMO channel and/or the CQI of the MIMO channel,

23. The system of claim 17, in which the first transceiver is a controlling node for a cell in the system.

24. The system of claim 17, in which the first transceiver is an LTE eNodeB.

25. The system of claim 17, wherein the first transceiver is an LTE user terminal.

26. The system of claim 17, in which the first transceiver is arranged to activate a first subset of a plurality of repeaters and to deactivate a second subset of the plurality of repeaters, said activation and deactivation being based on predetermined criteria.

27. The system of claim 17, in which said predetermined criteria include the rank and/or the CQI of the channel between the first transceiver and at least one user in the first cell.

28. The system of claim 26, in which said predetermined criteria include the interference caused by a second repeater to the communication between the first transceiver and at least one other transceiver.

29. The system of claim 26, in which the first transceiver is arranged to activate and/or deactivate first and/or second subsets of repeaters based on one or more of the following criteria:

for a certain channel rank Q to one or more user in the first cell, activate only the subset which renders the smallest ratio between the largest and smallest singular values, i.e. the channel condition number,

for a certain channel rank Q to one or more user in the first cell, activate only the subset that renders the largest value for the smallest singular value λ

_Q, i.e. the strongest weak channel,

activate only the subset which fulfils a certain requirement for capacity or throughput or which maximizes it,

activate only the subset which comprises the repeaters which have a composite channel path gain which exceeds a certain threshold.