Channel quality reporting for different types of subframes

• US 8,886,250 B2
• Filed: 06/17/2011
• Issued: 11/11/2014
• Est. Priority Date: 06/18/2010
• Status: Expired due to Fees

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Barbieri, Alan, Vajapeyam, Madhavan Srinivasan, Ji, Tingfang
• Primary Examiner(s): Rego, Dominic E
• Application Number:
  US13/163,595
• Publication Number:
  US 20110312358A1
• Time in Patent Office: 1,243 Days
• Field of Search: 455/552.1, 455436-442, 455/452.2, 455/135, 455/161.3, 455/277.2, 455/524, 455/525, 370331-334, 370/252
• US Class Current: 455/524
• CPC Class Codes: H04W 24/06 Testing, supervising or monitoring using simulated traffic
• CPC Class Codes: H04W 24/10 Scheduling measurement reports ; Arrangements for measurement reports
• CPC Class Codes: H04W 72/541 using the level of interference

Abstract

A method for determining channel quality estimates of two or more types of subframes, such as clean and unclean subframes, may be applicable to both legacy and newer user equipment. A first base station affects a channel quality measurement by either transmitting dummy signals over designed tones that correspond to a second base station, or by puncturing transmissions during designated tones that correspond to the second base station.

Claims

1. A method for channel quality estimation by a first base station in a wireless network, comprising:

determining a subframe in which a user equipment (UE) served by a second base station will perform a channel quality measurement; and

affecting the channel quality measurement by at least one of;

transmitting dummy signals over designated tones corresponding to the second base station on a first selected subband during the subframe; and

puncturing transmissions during designated tones corresponding to the second base station over a second selected subband during the subframe.

2. The method of claim 1, in which the determining comprises at least one of:

negotiating over a backhaul between the first and second base stations to identify the subframe; and

identifying the subframe by a predetermined rule.

3. The method of claim 1, in which the designated tones comprise common reference signals (CRS).

4. The method of claim 3, in which transmitting dummy signals comprises transmitting dummy signals on a first portion of CRS tones in the first subband to simulate a partially loaded system, the first portion depending on a load of the first base station.

5. The method of claim 3, in which puncturing transmissions comprises puncturing a second portion of the CRS tones in the second subband to simulate a partially loaded system, the second portion depending on a load of the first base station.

6. The method of claim 1, in which the first and second subbands are at least one of:

statically assigned, semi-statically negotiated among involved base stations, and

dynamically changing following predefined hopping patterns.

7. The method of claim 1, further comprising combining consecutive channel quality reports corresponding to a same type of subframe and different subbands;

and

obtaining a wideband report via statistical analysis of the consecutive channel quality reports.

8. An apparatus for wireless communication, comprising:

means for determining a subframe in which a user equipment (UE) served by a second base station will perform a channel quality measurement; and

means for affecting the channel quality measurement by at least one of;

transmitting dummy signals over designated tones corresponding to the second base station on a first selected subband during the subframe; and

puncturing transmissions during designated tones corresponding to the second base station over a second selected subband during the subframe.

9. A computer program product for wireless communication in a wireless network, comprising:

a non-transitory computer-readable medium having non-transitory program code recorded thereon, the program code comprising;

program code to determine a subframe in which a user equipment (UE) served by a second base station will perform a channel quality measurement; and

program code to affect the channel quality measurement by at least one of;

transmitting dummy signals over designated tones corresponding to the second base station on a first selected subband during the subframe; and

puncturing transmissions during designated tones corresponding to the second base station over a second selected subband during the subframe.

10. An apparatus for wireless communication, comprising:

a memory; and

at least one processor coupled to the memory, the at least one processor being configured;

to determine a subframe in which a user equipment (UE) served by a second base station will perform a channel quality measurement; and

to affect the channel quality measurement by at least one of;

transmitting dummy signals over designated tones corresponding to the second base station on a first selected subband during the subframe; and

puncturing transmissions during designated tones corresponding to the second base station over a second selected subband during the subframe.

11. The apparatus of claim 10, in which the processor is configured to determine a subframe by at least one of:

negotiating over a backhaul between the first and second base stations to identify the subframe; and

identifying the subframe by a predetermined rule.

12. The apparatus of claim 10, in which the designated tones comprise common reference signals (CRS).

13. The apparatus of claim 12, in which the processor is further configured to affect the channel quality measurement by transmitting dummy signals to a first portion of CRS tones in the first subband to simulate a partially loaded system, the first portion depending on a load of the first base station.

14. The apparatus of claim 12, in which the processor is further configured to affect the channel quality measurement by puncturing a second portion of the CRS tones in the second subband to simulate a partially loaded system, the second portion depending on a load of the first base station.

15. The apparatus of claim 10, in which the first and second subbands are at least one of:

statically assigned, semi-statically negotiated among involved base stations, and

dynamically changing following predefined hopping patterns.

16. The apparatus of claim 10, in which the processor is further configured:

to combine consecutive channel quality reports corresponding to a same type of subframe and different subbands; and

to obtain a wideband report via statistical analysis based on the consecutive channel quality reports.

17. A method for channel quality estimation by a first base station in a wireless network, comprising:

determining a subframe in which a user equipment (UE) will perform a channel quality measurement; and

affecting the channel quality measurement at the UE by puncturing transmissions during designated tones corresponding to a second base station over selected resources during the subframe.

18. The method of claim 17, in which the designated tones are reference signals transmitted by the second base station.

19. The method of claim 18, in which the reference signals comprise channel state information reference signals (CSI-RS) transmitted by the second base station.

20. The method of claim 17, in which the determining comprises at least one of:

negotiating over a backhaul between the first and second base stations to identify the subframe; and

identifying the subframe by a predetermined rule.

21. The method of claim 17, in which puncturing transmissions comprises simulating a partially loaded system based on a load at the first base station.

22. An apparatus for wireless communication, comprising:

a memory; and

at least one processor coupled to the memory, the at least one processor being configured to;

determine a subframe in which a user equipment (UE) will perform a channel quality measurement; and

affect the channel quality measurement at the UE by puncturing transmissions during designated tones corresponding to a second base station over selected resources during the subframe.

23. The apparatus of claim 22, in which the designated tones are reference signals transmitted by the second base station.

24. The method of claim 23, in which the reference signals comprise channel state information reference signals (CSI-RS) transmitted by the second base station.

25. The apparatus of claim 22, in which the determining comprises at least one of:

negotiating over a backhaul between the first and second base stations to identify the subframe; and

identifying the subframe by a predetermined rule.

26. The apparatus of claim 22, in which puncturing transmissions comprises simulating a partially loaded system based on a load at the first base station.

27. An apparatus for wireless communication, comprising:

means for determining a subframe in which a user equipment (UE) will perform a channel quality measurement; and

means for affecting the channel quality measurement at the UE by puncturing transmissions during designated tones corresponding to a second base station over selected-resources during the subframe.

28. A computer program stored on a non-transitory computer readable medium, comprising code for:

determining a subframe in which a user equipment (UE) will perform a channel quality measurement; and

affecting the channel quality measurement at the UE by puncturing transmissions during designated tones corresponding to a second base station over selected resources during the subframe.