Interference management for dynamic uplink and downlink configuration

• US 9,197,683 B2
• Filed: 09/12/2012
• Issued: 11/24/2015
• Est. Priority Date: 01/27/2012
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Intel Corporation
• Inventors: Fwu, Jong-Kae, Chatterjee, Debdeep, Shilov, Mikhail, Charvyakov, Andrey, Panteleev, Sergey, He, Hong, Khoryaev, Alexey
• Primary Examiner(s): Lee, Jae Y
• Assistant Examiner(s): Voltaire, Jean F
• Application Number:
  US13/612,318
• Publication Number:
  US 20130194982A1
• Time in Patent Office: 1,168 Days
• Field of Search: 370/280, 370/329
• US Class Current: 1/1
• CPC Class Codes: H04B 1/69 Spread spectrum techniques
• CPC Class Codes: H04B 7/024 Co-operative use of antennas of several sites, e.g. in co-ordinated multipoint or co-operative multiple-input multiple-output [MIMO] systems
• CPC Class Codes: H04B 7/0413 MIMO systems
• CPC Class Codes: H04B 7/0456 Selection of precoding matrices or codebooks, e.g. using matrices antenna weighting
• CPC Class Codes: H04B 7/0617 for beam forming
• CPC Class Codes: H04B 7/0623 Auxiliary parameters, e.g. power control [PCB] or not acknowledged commands [NACK], used as feedback information
• CPC Class Codes: H04B 7/0626 Channel coefficients, e.g. channel state information [CSI]
• CPC Class Codes: H04B 7/0639 Using selective indices, e.g. of a codebook, e.g. pre-distortion matrix index [PMI] or for beam selection
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 1/0027 Scheduling of signalling, e.g. occurrence thereof
• CPC Class Codes: H04L 1/0031 Multiple signaling transmission H04L1/1664, F15 take precedence
• CPC Class Codes: H04L 1/1864 ARQ related signaling H04L1/1607 takes precedence
• CPC Class Codes: H04L 1/1887 Scheduling and prioritising arrangements
• CPC Class Codes: H04L 1/1896 ARQ related signaling
• CPC Class Codes: H04L 12/189 in combination with wireless systems selective distribution or broadcast in wireless communication networks H04W4/06
• CPC Class Codes: H04L 27/2607 Cyclic extensions
• CPC Class Codes: H04L 5/0035 Resource allocation in a cooperative multipoint environment
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/005 of common pilots, i.e. pilots destined for multiple users or terminals
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: H04L 5/1469 : using time-sharing
• CPC Class Codes: H04L 65/611 : for multicast or broadcast systems for broadcast or conference H04L12/18; arrangements for broadcast or distribution combined with broadcast H04H20/00; arrangements for broadcast applications with a direct linkage to broadcast information or to broadcast space-time H04H60/00; selective distribution of broadcast services, e.g. multimedia broadcast multicast service [MBMS], H04W4/06
• CPC Class Codes: H04L 65/65 : Network streaming protocols, e.g. real-time transport protocol [RTP] or real-time control protocol [RTCP]
• CPC Class Codes: H04W 36/0094 : Definition of hand-off measurement parameters
• CPC Class Codes: H04W 36/04 : Reselecting a cell layer in multi-layered cells
• CPC Class Codes: H04W 4/08 : User group management
• CPC Class Codes: H04W 4/70 : Services for machine-to-machine communication [M2M] or machine type communication [MTC]
• CPC Class Codes: H04W 48/16 : Discovering, processing access restriction or access information
• CPC Class Codes: H04W 52/0216 : using a pre-established activity schedule, e.g. traffic indication frame
• CPC Class Codes: H04W 72/04 : Wireless resource allocation
• CPC Class Codes: H04W 72/044 : based on the type of the allocated resource
• CPC Class Codes: H04W 72/20 : Control channels or signalling for resource management
• CPC Class Codes: H04W 72/23 : in the downlink direction of a wireless link, i.e. towards a terminal
• CPC Class Codes: H04W 72/53 : based on regulatory allocation policies
• CPC Class Codes: H04W 72/541 : using the level of interference
• CPC Class Codes: H04W 72/542 : using measured or perceived quality
• CPC Class Codes: H04W 76/27 : Transitions between radio resource control [RRC] states
• CPC Class Codes: H04W 76/28 : Discontinuous transmission [DTX]; Discontinuous reception [DRX]
• CPC Class Codes: Y02D 30/70 : in wireless communication networks

Abstract

An apparatus and method for managing interference to facilitate allocation of a dynamic uplink and downlink configuration are disclosed herein. Determining whether a first cell causes interference less than a pre-determined threshold level to one or more neighboring cells or whether flexible subframes of radio frames associated with the one or more neighboring cells operate as downlink subframes. In response to the determining condition being met, allocating a first flexible subframe of a first radio frame associated with the first cell to operate as a downlink subframe at normal transmit power level. In response to the determining condition not being met, allocating the first flexible subframe of the first radio frame associated with the first cell as one of a downlink subframe operating in a reduced transmit power level or as an uplink subframe.

Claims

1. A method for operating a base station in a Long Term Evolution (LTE) network, the method comprising:

transmitting an uplink/downlink (UL/DL) configuration for TDD (time division duplex) mode to user equipments (UEs) within a cell served by the based station in a system information block SIB1, where the UL/DL configuration indicates whether a subframe if a radio frame is a UL subframe, a DL subframe, or a flexible subframe operable as either a DL subframe or a UL subframe after dynamic UL/DL reconfiguration; and

,

performing a dynamic UL/DL reconfiguration that defines a first flexible subframe as either a DL subframe or a UL subframe according to traffic conditions;

when the first flexible subframe is defined as a DL subframe, operating the first flexible subframe at a normal power level when either;

     1) DL interference caused by the cell to one or more neighboring cells does not exceed a pre-determined threshold, or

     2) a majority of flexible subframes in neighboring cells are defined as DL subframes; and

,

when the first flexible subframe is defined as a DL subframe, operating the first flexible subframe at a reduced power level that is less than the normal power level when;

     1) DL interference caused by the cell to one or more neighboring cells exceeds a pre-determined threshold, and

     2) less than a majority of flexible subframes in neighboring cells are defined as DL subframes.

2. The method of claim 1, wherein the cell comprises a macro cell and is associated with a macro eNodeB.

3. The method of claim 2, further comprising determining the DL interference caused by the cell to the one or more neighboring cells and an UL/DL ratio in those cells by communicating with the one or more neighboring cells via an X2 interface.

4. The method of claim 1, wherein the cell comprises a LPN cell.

5. The method of claim 1, wherein the dynamic UL/DL reconfiguration is performed on a radio frame basis.

6. The method of claim 1, wherein the dynamic UL/DL reconfiguration is performed on a subframe basis.

7. The method of claim 1, further comprising transmitting dynamic UL/DL reconfiguration information to UEs in the cell via higher-layer semi-static signaling or physical layer dynamic signaling.

8. A base station for operating a cell in a Long Term Evolution (LTE) network, comprising:

a processor in communication with a transceiver, wherein the processor and transceiver are to;

transmit an uplink/downlink (UL/DL) configuration for TDD (time division duplex) mode to user equipments (UEs) within the cell in a system information block SIB1, where the UL/DL configuration indicates whether a subframe of a radio frame is a UL subframe, a DL subframe, or a flexible subframe operable as either a DL subframe or a UL subframe after dynamic UL/DL reconfiguration; and

,

perform a dynamic UL/DL reconfiguration that defines a first flexible subframe as either a DL subframe or a UL subframe according to traffic conditions;

when the first flexible subframe is defined as a DL subframe, operate the first flexible subframe at a normal power level when either;

     1) DL interference caused by the cell to one or more neighboring cells does not exceed a pre-determined threshold or

     2) a majority of flexible subframes in neighboring cells are defined as DL subframes; and

,

when the first flexible subframe is defined as a DL subframe, operate the first flexible subframe at a reduced power level that is less than the normal power level when;

     1) DL interference caused by the cell to one or more neighboring cells exceeds a pre-determined threshold, and

     2) less than a majority of flexible subframes in neighboring cells are defined as DL subframes.

9. The base station of claim 8, wherein the base station comprises a low power node (LPN) and the cell comprises a LPN cell.

10. The base station of claim 8, wherein the base station comprises a macro enhanced node B (eNodeB) and the cell comprises a macro cell.

11. The base station of claim 10, wherein the processor is to determine the DL interference caused by the cell to the one or more neighboring cells and an UL/DL ratio in those cells by communicating with the one or more neighboring cells via an X2 interface.

12. The base station of claim 10, wherein the processor and transceiver are to transmit dynamic UL/DL reconfiguration information to UEs in the cell via a downlink control information (DCI) message.

13. The base station of claim 8, wherein the processor and transceiver are to signal the dynamic uplink and downlink configuration to user equipment (UEs) associated with the cell without using system information block 1 (SIB1), the dynamic uplink and downlink configuration including information about the allocated first flexible subframe.

14. The base station of claim 8, wherein the radio frame comprises ten subframes that are identifiable by subframe index numbers 0 through 9 from left to right, the first flexible subframe comprising one or more subframes corresponding to the subframe index number 3, subframe index number 4, subframe index number 7, subframe index number 8, or subframe index number 9.

15. The base station of claim 8, wherein the processor and transceiver are to transmit dynamic UL/DL reconfiguration information to UEs in the cell via higher-layer semi-static signaling or physical layer dynamic signaling.

16. The base station of claim 8, wherein the processor is to perform the dynamic UL/DL reconfiguration on a subframe level basis.

17. The base station of claim 8, wherein the processor is to perform the dynamic UL/DL reconfiguration on a radio frame level basis.

18. The base station of claim 8, wherein the first flexible subframe configured as an uplink subframe after a downlink subframe is a special uplink subframe that includes a downlink transmission period to transmit downlink control channels, a central guard period (GP) to switch between a downlink and uplink transmission, and an uplink data transmission period.

19. A non-transitory computer readable medium including instructions, when executed by a processor, causes the processor to perform operations comprising:

transmitting an uplink/downlink (UL/DL) configuration for TDD (time division duplex) mode to user equipments (UEs) within a cell served by the based station in a system information block SIB1 where the UL/DL configuration indicates whether a subframe of a radio frame is a UL subframe, a DL subframe, or a flexible subframe operable as either a DL subframe or a UL subframe after dynamic UL/DL reconfiguration; and

,

performing a dynamic UL/DL reconfiguration that defines a first flexible subframe as either a DL subframe or a UL subframe according to traffic conditions;

when the first flexible subframe is defined as a DL subframe, operating the first flexible subframe at a normal power level when either;

     1) DL interference caused by the cell to one or more neighboring cells does not exceed a pre-determined threshold, or

     2) a majority of flexible subframes in neighboring cells are defined as DL subframes; and

,

when the first flexible subframe is defined as a DL subframe, operating the first flexible subframe at a reduced power level that is less than the normal power level when;

     1) DL interference caused by the cell to one or more neighboring cells exceeds a pre-determined threshold and

     2) less than a majority of flexible subframes in neighboring cells are defined as DL subframes.

20. The non-transitory computer readable medium of claim 19, further including instructions for determining the DI, interference caused by the cell to the one or more neighboring cells and an UL/DL ratio in those cells by communicating with the one or more neighboring cells via an X2 interface.

21. The non-transitory computer readable medium of claim 19, further including instructions for transmitting dynamic UL/DL reconfiguration information to UEs in the cell via higher-layer semi-static signaling.

22. The non-transitory computer readable medium of claim 19, further including instructions for transmitting dynamic UL/DL reconfiguration information to UEs in the cell via radio resource control (RRC) signaling.

23. The non-transitory computer readable medium of claim 19 further including instructions for transmitting dynamic UL/DL reconfiguration information to UEs in the cell via physical layer dynamic signaling.

24. The non-transitory computer readable medium of claim 19, wherein the radio frame comprises ten subframes that are identifiable by subframe index numbers 0 through 9 from left to right, the first flexible subframe comprising one or more subframes corresponding to the subframe index number 3, subframe index number 4, subframe index number 7, subframe index number 8, or subframe index number 9.