Mode Switching Between SU-MIMO and MU-MIMO

• US 20100322330A1
• Filed: 04/03/2008
• Published: 12/23/2010
• Est. Priority Date: 06/27/2007
• Status: Active Grant

• Current Assignee: Unwired Planet LLC (JP Morgan Chase & Co)
• Original Assignee: Unwired Planet LLC (JP Morgan Chase & Co)
• Inventors: Goransson, Bo, Wan, Lei, Jongren, George
• Granted Patent: US 8,989,290 B2
• Time in Patent Office: Days
• US Class Current: 375/260
• CPC Class Codes: H04B 7/0452 Multi-user MIMO systems
• CPC Class Codes: H04B 7/0469 taking special antenna structures, e.g. cross polarized antennas into account
• CPC Class Codes: H04B 7/0486 taking channel rank into account
• CPC Class Codes: H04B 7/0689 using different transmission schemes, at least one of them being a diversity transmission scheme
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04W 52/36 with a discrete range or set of values, e.g. step size, ramping or offsets
• CPC Class Codes: H04W 52/54 Signalisation aspects of the TPC commands, e.g. frame structure
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals
• CPC Class Codes: H04W 88/10 adapted for operation in multiple networks, e.g. multi-mode access points

Abstract

The present invention relates to a method and arrangements in a communication system for Multi User Multiple-Input-Multiple-Output (MU-MIMO) signaling via Multiple-Input-Multiple-Output (MIMO) antennas between a base station and one of a plurality of mobile terminals supporting both Single User and Multi User Multiple-Input-Multiple-Output (SU-MIMO and MU-MIMO) signaling modes. Switching between the modes is supported in the system and the modes have partly shared signaling. SU-MIMO mode signaling which is redundant, i.e. not needed, for MU-MIMO mode signaling is identified. Bits, i.e. data bits, of the identified redundant signaling is re-interpreted or re-defined to comprise signaling information associated with MU-MIMO mode. The signaling information associated with MU-MIMO mode is signaled to the mobile terminal by using the reinterpreted redundant bits.

Claims

1-16. -16. (canceled)

17. A method for a base station for Multi User Multiple-Input-Multiple-Output (MU-MIMO) signaling from MIMO antennas of a base station to one of a plurality of mobile terminals of a communication system configured for both Single User MIMO (SU-MIMO) and MU-MIMO signaling modes and configured to switch between said modes, wherein said modes have partly shared signaling, the method comprising:

identifying SU-MIMO signaling, which is redundant for the MU-MIMO mode, and reinterpreting bits of said redundant signaling to comprise signaling information associated with MU-MIMO mode;

informing the mobile terminal via signaling about the reinterpretation of the redundant bits; and

signaling information associated with MU-MIMO mode by using said reinterpreted redundant bits.

18. The method of claim 17, wherein the redundant signaling relates to at least one of transmission rank signaling and precoder element signaling.

19. The method of claim 17, wherein said MU-MIMO signaling information comprises a power offset between a power reference and data symbols.

20. The method of claim 19, wherein said power reference is reference symbols (RS).

21. The method of claim 17, wherein said MU-MIMO signaling information comprises a total number of terminals.

22. The method of claim 17, wherein said reinterpreted redundant bits are signaled whenever the terminal is scheduled.

23. A radio base station in a communication system comprising Multiple-Input-Multiple-Output (MIMO) antennas for signaling to one of a plurality of mobile terminals and configured for both Single User MIMO (SU-MIMO) and Multi User MIMO (MU-MIMO) signaling modes, wherein said base station comprises:

a controller for switching between said modes, said modes having partly shared signaling; and

a processor for identifying SU-MIMO mode signaling which is redundant for MU-MIMO mode, and for reinterpreting bits of said redundant signaling to comprise signaling information associated with MU-MIMO mode; and

a transmitter for informing the UE about the reinterpretation of the redundant bits and signaling information associated with MU-MIMO mode by using said reinterpreted redundant bits.

24. The radio base station of claim 23, wherein the redundant signaling relates to at least one of transmission rank signaling and precoder element signaling.

25. The radio base station of claim 23, wherein said MU-MIMO signaling information comprises a power offset between a power reference and data symbols of said one terminal.

26. The radio base station of claim 25, wherein said power reference is reference symbols (RS).

27. The radio base station of claim 23, wherein said MU-MIMO signaling information comprises a total number of terminals.

28. A mobile terminal comprising Multiple-Input-Multiple-Output (MIMO) antennas configured for both Single User MIMO (SU-MIMO) and Multi User MIMO (MU-MIMO) signaling modes, wherein said mobile terminal comprises:

a controller for switching between said modes, said modes having partly shared signaling; and

a receiver for receiving from the base station information about a reinterpretation of redundant SU-MIMO bits, and signaling information associated with MU-MIMO mode by receiving said reinterpreted redundant bits; and

a processor for interpreting said reinterpreted redundant bits by using the information about the reinterpretation of redundant SU-MIMO bits.

29. The mobile terminal of claim 28, wherein the redundant signaling relates to transmission rank signaling and/or precoder element signaling.

30. The mobile terminal of claim 28, wherein said MU-MIMO signaling information comprises a power offset between a power reference and data symbols of said one mobile terminal.

31. The mobile terminal of claim 30, wherein said power reference is reference symbols (RS).

32. The mobile terminal of claim 28, wherein said MU-MIMO signaling information comprises a total number of terminals.