Interference cancellation/suppression in TDD wireless communications systems

• US 10,091,766 B2
• Filed: 03/31/2014
• Issued: 10/02/2018
• Est. Priority Date: 04/05/2013
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Chen, Wanshi, Luo, Tao, Xu, Hao, Gaal, Peter, Yoo, Taesang, Wei, Yongbin, Malladi, Durga Prasad
• Primary Examiner(s): La, Phong
• Application Number:
  US14/230,464
• Publication Number:
  US 20140301251A1
• Time in Patent Office: 1,646 Days
• Field of Search: 370278
• CPC Class Codes: H04J 11/005 of intercell interference
• CPC Class Codes: H04L 5/003 Arrangements for allocating sub-channels of the transmission path
• CPC Class Codes: H04W 72/02 Selection of wireless resources by user or terminal
• CPC Class Codes: H04W 72/541 using the level of interference

Abstract

A wireless user equipment (UE) may receive a downlink transmission from a base station in a first subframe of a first subframe configuration, and determine that a neighboring base station is operating according to a second subframe configuration. The UE may modify interference operations for the downlink transmission in the first subframe based on the determination to account for the neighboring base station operating according to the different subframe configuration. Modifying interference operations may include, for example, skipping interference operations, applying different interference operations to a subframe or a portion of a subframe, or a combination thereof. Modifying interference operations may be based on one or more characteristics of the neighboring base station communications.

Claims

1. A method for wireless communications performed by a user equipment (UE), comprising:

receiving from a base station a first subframe of a first subframe configuration;

receiving a reference signal of a neighboring base station;

determining that the neighboring base station is operating according to a neighboring subframe configuration during the first subframe based on information associated with the received reference signal, the neighboring subframe configuration being different from the first subframe configuration;

modifying interference cancellation/interference suppression (IC/IS) operations for the first subframe based on the determination that the neighboring base station is operating according to the neighboring subframe configuration during the first subframe; and

modifying IC/IS operations for a third subframe in response to a third subframe configuration being the same as a fourth subframe configuration.

2. The method of claim 1, wherein the modifying IC/IS operations comprises at least partly skipping the IC/IS operations during at least a portion of the first subframe.

3. The method of claim 1, wherein the first subframe configuration is one of a downlink subframe, an uplink subframe or a special subframe, and the neighboring subframe configuration is one of the downlink subframe, the uplink subframe or the special subframe.

4. The method of claim 1, further comprising:

receiving information from the base station identifying at least a portion of one or more subframes in which the IC/IS operations are to be at least partly skipped.

5. The method of claim 4, wherein the information comprises an indication of a time-division duplex (TDD) uplink/downlink (UL/DL) configuration for the neighboring base station and a subset of subframes containing interference is determined based on the TDD UL/DL configuration for the neighboring base station.

6. The method of claim 1, wherein the determining that the neighboring base station is operating according to the neighboring subframe configuration comprises:

detecting whether a neighboring subframe for the neighboring base station, that at least partly overlaps the first subframe, comprises one or more of a downlink transmission or an uplink transmission.

7. The method of claim 6, wherein the detecting comprises:

determining whether the neighboring subframe for the neighboring base station comprises one or both of a downlink transmission and an uplink transmission based at least in part on information associated with the reference signal.

8. The method of claim 6, further comprising:

determining the neighboring subframe configuration based at least in part on a resource block of the neighboring base station and an assumption that all transmitted subframes of the neighboring base station are consistent with the information in the resource block.

9. The method of claim 1, further comprising:

receiving from the base station the third subframe of the third subframe configuration, the third subframe comprising a first special subframe (SSF); and

determining that the neighboring base station is operating according to the fourth subframe configuration during the third subframe.

10. The method of claim 9, wherein the modifying IC/IS operations comprises at least partly skipping the IC/IS operations during at least a portion of the third subframe for the first SSF.

11. A non-transitory computer-readable medium, comprising code executable by a processor of a user equipment (UE) for:

receiving from a base station a first subframe of a first subframe configuration;

receiving a reference signal of a neighboring base station;

determining that a neighboring base station is operating according to a neighboring subframe configuration during the first subframe based on information associated with the received reference signal, the neighboring subframe configuration being different from the first subframe configuration;

modifying interference cancellation/interference suppression (IC/IS) operations for the first subframe based on the determination that the neighboring base station is operating according to the neighboring subframe configuration during the first subframe; and

modifying IC/IS operations for a third subframe in response to a third subframe configuration being the same as a fourth subframe configuration.

12. The non-transitory computer-readable medium of claim 11, wherein the code for modifying IC/IS operations comprises code for at least partly skipping the IC/IS operations during at least a portion of the first subframe.

13. The non-transitory computer-readable medium of claim 11, wherein the first subframe configuration is one of a downlink subframe, an uplink subframe or a special subframe, and the neighboring subframe configuration is one of a downlink subframe, an uplink subframe or a special subframe.

14. The non-transitory computer-readable medium of claim 11, further comprising code executable by the processor of the UE for:

receiving information from the base station identifying at least a portion of one or more subframes in which the IC/IS operations are to be at least partly skipped.

15. The non-transitory computer-readable medium of claim 11, further comprising code executable by the processor of the UE for:

detecting whether a neighboring subframe for the neighboring base station, that at least partly overlaps the first subframe, comprises one or both of a downlink transmission and an uplink transmission.

16. The non-transitory computer-readable medium of claim 15, wherein the code for detecting further comprises code executable by the processor of the UE for:

determining whether the neighboring subframe for the neighboring base station comprises one or both of a downlink transmission and an uplink transmission based on information associated with the reference signal.

17. The non-transitory computer-readable medium of claim 15, further comprising:

determining the neighboring subframe configuration based at least in part on a resource block of the neighboring base station and an assumption that all transmitted subframes of the neighboring base station are consistent with information in the resource block.

18. The non-transitory computer-readable medium of claim 11, further comprising code executable by the processor of the UE for:

receiving from the base station the third subframe of the third subframe configuration, the third subframe comprising a first special subframe (SSF); and

determining that the neighboring base station is operating according to the fourth subframe configuration during the third subframe.

19. The non-transitory computer-readable medium of claim 18, wherein the modifying IC/IS operations comprises at least partly skipping the IC/IS operations during at least a portion of the third subframe for the first SSF.

20. A device for wireless communication, comprising:

a processor; and

a memory in electronic communication with the processor, the memory embodying instructions, the instructions being executable by the processor to;

receive from a base station a first subframe of a first subframe configuration;

receive a reference signal of a neighboring base station;

determine that a neighboring base station is operating according to a neighboring subframe configuration during the first subframe based on information associated with the received reference signal, the neighboring subframe configuration being different from the first subframe configuration;

modify interference cancellation/interference suppression (IC/IS) operations for the first subframe based on the determination that the neighboring base station is operating according to the neighboring subframe configuration during the first subframe; and

modify IC/IS operations for a third subframe in response to a third subframe configuration being the same as a fourth subframe configuration.

21. The device of claim 20, wherein the modifying IC/IS operations comprises at least partly skipping the IC/IS operations during at least a portion of the first subframe.

22. The device of claim 20, wherein the first subframe configuration is one of a downlink subframe, an uplink subframe or a special subframe, and the neighboring subframe configuration is one of a downlink subframe, an uplink subframe or a special subframe.

23. The device of claim 20, wherein the instructions are further executable to:

receive information from the base station identifying at least a portion of one or more subframes in which the IC/IS operations are to be at least partly skipped.

24. The device of claim 23, wherein the information comprises an indication of a time-division duplex (TDD) uplink/downlink (UL/DL) configuration for the neighboring base station and a subset of subframes containing interference is determined based on the TDD UL/DL configuration for the neighboring base station.

25. The device of claim 20, wherein the instructions to determine that the neighboring base station is operating according to the neighboring subframe configuration include instructions to:

detect whether a neighboring subframe for the neighboring base station, that at least partly overlaps the first subframe, comprises one or more of a downlink transmission or an uplink transmission.

26. The device of claim 25, wherein the instructions to detect include instructions to:

determine whether the neighboring subframe for the neighboring base station comprises one or both of a downlink transmission and an uplink transmission based on information associated with the reference signal.

27. The device of claim 25, wherein the instructions are further executable to:

determine the neighboring subframe configuration based at least in part on a resource block of the neighboring base station and an assumption that all transmitted subframes of the neighboring base station are consistent with information in the resource block.

28. A method for wireless communications performed by a base station, comprising:

identifying a first subframe configuration for a first subframe associated with a user equipment (UE);

determining that a neighboring base station is operating according to a neighboring subframe configuration during the first subframe, the neighboring subframe configuration being different from the first subframe configuration;

transmitting information to the UE identifying the first subframe for IC/IS modification, the information comprising a bitmap identifying a subset of subframes; and

modifying interference cancellation/interference suppression (IC/IS) operations for the first subframe based on the determination that the neighboring base station is operating according to the neighboring subframe configuration during the first subframe, wherein modifying IC/IS operations comprises at least partly skipping the IC/IS operations during at least a portion of the first subframe.