INTERFERENCE CANCELLATION

• US 20110267937A1
• Filed: 04/28/2011
• Published: 11/03/2011
• Est. Priority Date: 04/30/2010
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Zhao, Lu, Luo, Tao, Yoo, Taesang
• Granted Patent: US 8,737,187 B2
• Time in Patent Office: Days
• US Class Current: 370/201
• CPC Class Codes: H04J 11/005 of intercell interference
• CPC Class Codes: H04L 25/0204 of multiple channels
• CPC Class Codes: H04L 25/0224 using sounding signals
• CPC Class Codes: H04L 5/005 of common pilots, i.e. pilots destined for multiple users or terminals
• CPC Class Codes: H04L 5/0062 Avoidance of ingress interference, e.g. ham radio channels
• CPC Class Codes: H04L 5/0073 Allocation arrangements that take into account other cell interferences for intercell interference mitigation or co-ordination in orthogonal multiplex systems H04J11/005
• CPC Class Codes: H04W 24/10 Scheduling measurement reports ; Arrangements for measurement reports

Abstract

A method to enhance coverage and/or throughput in a heterogeneous wireless network includes detecting interference between a neighboring cell and a serving cell. The method also includes cancelling the interference using an adaptive technique based on whether the interference has colliding Common Reference Signal (CRS) tones.

Claims

1. A method to enhance coverage and/or throughput in a heterogeneous wireless network, the method comprising:

detecting interference between a neighboring cell and a serving cell; and

cancelling the interference using an adaptive technique based on whether the interference has colliding Common Reference Signal (CRS) tones.

2. The method of claim 1, in which cancelling interference comprises:

processing common reference signal (CRS) tones of the neighboring cell and the serving cell when the interference has colliding CRS tones; and

processing at least one of control and data channels of the serving cell and the neighboring cell.

3. The method of claim 2, in which processing CRS tones comprises:

estimating a neighboring cell channel;

cancelling interference from the neighboring cell CRS tones to estimate a serving cell channel; and

estimating the serving cell channel; and

in which processing the at least one of control and data channels comprises;

decoding at least one of neighboring cell control and data channels;

cancelling interference from at least one of the neighboring cell control and data channels using the decoded at least one of the neighboring cell control and data channels; and

decoding at least one of serving cell control and data channels.

4. The method of claim 2, in which processing CRS tones comprises:

iteratively estimating neighbor cell channels and serving cell channels by iterative interference cancellation on serving cell CRS tones and neighbor cell CRS tones.

5. The method of claim 2, in which processing the at least one of control and data channels comprises:

iteratively decoding and cancelling at least one of neighboring cell control and data channels and at least one of serving cell control and data channels.

6. The method of claim 1, in which cancelling interference comprises:

processing common reference signal (CRS) tones of the neighboring cell;

processing at least one of control and data channels of the neighboring cell;

processing common reference signal (CRS) tones of the serving cell; and

decoding at least one of control and data channels of the serving cell.

7. The method of claim 6, in which processing CRS tones of the neighboring cell comprises:

estimating a channel of the neighboring cell; and

cancelling interference from estimated neighboring cell CRS tones; and

in which processing the at least one of control and data channels of the neighboring cell comprises;

decoding at least one of the control and data channels of the neighboring cell; and

cancelling neighbor control and data channels using the neighbor cell channel estimate.

8. The method of claim 7, further comprising:

iteratively performing estimating, cancelling interference from estimated neighboring cell CRS tones, decoding, cancelling neighbor control and data channels, cancelling serving cell CRS tones and cancelling at least one of the serving cell control and data channels.

9. The method of claim 7, further comprising:

cancelling serving cell CRS tones;

cancelling at least one of the serving cell control and data channels; and

iteratively performing estimating, cancelling interference from estimated neighboring cell CRS tones, decoding, cancelling neighbor control and data channels, cancelling serving cell CRS tones and cancelling at least one of the serving cell control and data channels.

10. An apparatus to enhance coverage in a heterogeneous wireless network, comprising:

means for detecting interference between a neighboring cell and a serving cell; and

means for cancelling the interference using an adaptive technique based on whether the interference has colliding Common Reference Signal (CRS) tones.

11. An apparatus to enhance coverage in a heterogeneous wireless network, comprising:

a memory; and

at least one processor coupled to the memory and configured;

to detect interference between a neighboring cell and a serving cell; and

to cancel the interference using an adaptive technique based on whether the interference has colliding Common Reference Signal (CRS) tones.

12. The apparatus of claim 11, in which the processor is further configured to cancel interference by:

processing common reference signal (CRS) tones of the neighboring cell and the serving cell when the interference has colliding CRS tones; and

processing at least one of control and data channels of the serving cell and the neighboring cell.

13. The apparatus of claim 12, in which the processor is further configured to process CRS tones by:

estimating a neighboring cell channel;

cancelling interference from the neighboring cell CRS tones to estimate a serving cell channel; and

estimating the serving cell channel; and

in which the processor is further configured to process the at least one of control and data channels by;

decoding at least one of neighboring cell control and data channels;

cancelling interference from at least one of the neighboring cell control and data channels using the decoded at least one of the neighboring cell control and data channels; and

decoding at least one of serving cell control and data channels.

14. The apparatus of claim 12, in which the processor is further configured to process CRS tones by iteratively estimating neighbor cell channels and serving cell channels by iterative interference cancellation on serving cell CRS tones and neighbor cell CRS tones.

15. The apparatus of claim 12, in which the processor is further configured to process the at least one of control and data channels by iteratively decoding and cancelling at least one of neighboring cell control and data channels and at least one of serving cell control and data channels.

16. The apparatus of claim 11, in which the processor is further configured to cancel interference by:

processing common reference signal (CRS) tones of the neighboring cell;

processing at least one of control and data channels of the neighboring cell;

processing common reference signal (CRS) tones of the serving cell; and

decoding at least one of control and data channels of the serving cell.

17. The apparatus of claim 16, in which the processor is further configured to process CRS tones of the neighboring cell by:

estimating a channel of the neighboring cell; and

cancelling interference from estimated neighboring cell CRS tones; and

in which the processor is further configured to process the at least one of control and data channels of the neighboring cell by;

decoding at least one of the control and data channels of the neighboring cell; and

cancelling neighbor control and data channels using the neighbor cell channel estimate.

18. The apparatus of claim 17, in which the processor is further configured to:

iteratively perform estimating, cancelling interference from estimated neighboring cell CRS tones, decoding, cancelling neighbor control and data channels, cancelling serving cell CRS tones and cancelling at least one of the serving cell control and data channels.

19. The apparatus of claim 17, in which the processor is further configured:

to cancel serving cell CRS tones;

to cancel at least one of the serving cell control and data channels; and

to iteratively perform estimating, cancelling interference from estimated neighboring cell CRS tones, decoding, cancelling neighbor control and data channels, cancelling serving cell CRS tones and cancelling at least one of the serving cell control and data channels.

20. A computer program product for wireless communications in a wireless network, comprising:

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

program code to detect interference between a neighboring cell and a serving cell; and

program code to cancel the interference using an adaptive technique based on whether the interference has colliding Common Reference Signal (CRS) tones.