Communication apparatus and precoding method based on multiple cells and multiple users

• US 9,231,795 B2
• Filed: 11/02/2010
• Issued: 01/05/2016
• Est. Priority Date: 01/18/2010
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Shin, Won Jae, Lee, Nam Yoon, Hong, Young Jun, Shin, Chang Yong, Jang, Kyung Hun
• Primary Examiner(s): LIAO, HSINCHUN
• Application Number:
  US12/917,869
• Publication Number:
  US 20110177834A1
• Time in Patent Office: 1,890 Days
• Field of Search: 455/63.1, 455/67.13, 455/501, 455/509, 375/267
• US Class Current: 1/1
• CPC Class Codes: H04J 11/0033 by pre-cancellation of known interference, e.g. using a matched filter, dirty paper coder or Thomlinson-Harashima precoder correlative coding in synchronous or start-stop systems H04L25/497
• CPC Class Codes: H04J 11/0059 Out-of-cell user aspects
• CPC Class Codes: H04L 25/03343 Arrangements at the transmitter end

Abstract

Provided are a communication apparatus that may generate a precoding matrix including precoding vectors to cancel or align interference existing in a plurality of terminal devices based on location of the terminal devices, and a terminal device that may estimate a channel formed between the terminal device and the communication apparatus to cancel or align interference signals.

Claims

1. A precoding method, comprising:

aligning, in the same space, different interference channels corresponding to different terminal devices included in a cell edge region of an interference base station; and

generating a reception beamforming vector of one or more terminal devices included in a cell edge region of a serving base station, based on the aligned interference channels of the interference base station,

wherein the interference channels comprise a first interference channel of a first terminal and a second interference channel of a second terminal, and

wherein the aligning in the same space comprises calculating a rank of the first interference channel and the second interference channel to have a value of 1 or a proximate value of 1.

2. The precoding method of claim 1, further comprising:

generating a precoding vector of the one or more terminal devices included in the cell edge region of the serving base station, based on a basis vector of each of the interference channels of the interference base station that are aligned in the same space, and an interference channel of the serving base station.

3. The precoding method of claim 2, further comprising:

transmitting, to the one or more terminal devices included in the cell edge region of the serving base station, at least one of the reception beamforming vector and data that is precoded using the generated precoding vector.

4. The precoding method of claim 1, wherein the aligning comprises aligning, in the same space, the interference channels of the one or more terminal devices included in the cell edge region of the interference base station to be partially overlapped with each other.

5. The precoding method of claim 1, wherein the aligning in the same space is performed by calculating rank(w^[1,ī

]^HH_i<sup>[1,ī

]H</sup>, w<sup>[2,ī

]H</sup>H_i<sup>[2,ī

]H</sup>)≈

1.

6. The precoding method of claim 1, wherein the reception beamforming vector is obtained by using the aligned effective interference channels in the same space to discern the direction of the effective interference channels with respect to a basis vector.

7. The precoding method of claim 6, wherein the reception beamforming vector is obtained by calculating

8. A communication apparatus, comprising:

an interference channel alignment unit configured to align, in the same space, different interference channels corresponding to different terminal devices included in a cell edge region of an interference base station; and

a reception beamforming vector generator configured to generate a reception beamforming vector of one or more terminal devices included in a cell edge region of a serving base station, based on the aligned interference channels of the interference base station,

wherein the interference channels comprise a first interference channel of a first terminal and a second interference channel of a second terminal, and

wherein the aligning in the same space comprises calculating a rank of the first interference channel and the second interference channel to have a value of 1 or a proximate value of 1.

9. The communication apparatus of claim 8, further comprising:

a precoder configured to generate a precoding vector of the one or more terminal devices included in the cell edge region of the serving base station, based on a basis vector of each of the interference channels of the interference base station that are aligned in the same space, and an interference channel of the serving base station.

10. The communication apparatus of claim 9, wherein the precoder transmits, to the one or more terminal devices included in the cell edge region of the serving base station, at least one of the reception beamforming vector and data that are precoded using the generated precoding vector.

11. The communication apparatus of claim 8, wherein the interference channel alignment unit aligns, in the same space, the interference channels of the one or more terminal devices included in the cell edge region of the interference base station to be partially overlapped with each other.

12. A method of generating a reception beamforming, comprising:

obtaining different interference channels corresponding to different terminal devices included in a cell edge region of an interference base station;

aligning the obtained interference channels in the same space; and

generating a reception beamforming vector of one or more terminal devices included in a cell edge region of a serving base station, based on the aligned interference channels of the interference base station,

wherein the interference channels comprise a first interference channel of a first terminal and a second interference channel of a second terminal, and

wherein the aligning the obtained interference channels in the same space comprises calculating a rank of the first interference channel and the second interference channel to have a value of 1 or a proximate value of 1.

13. The method of claim 12 further comprising:

feeding back, to the serving base station, at least one of the aligned interference channels and a serving channel.

14. The method of claim 12, wherein the aligning comprises aligning, in the same space, the interference channels of the one or more terminal devices included in the cell edge region of the interference base station to be partially overlapped with each other.

15. A terminal device, comprising:

an interference channel obtainment unit configured to obtain different interference channels corresponding to different terminal devices included in a cell edge region of an interference base station;

an interference channel alignment unit configured to align the obtained interference channels in the same space; and

a reception beamforming vector generator configured to generate a reception beamforming vector of one or more terminal devices included in a cell edge region of a serving base station, based on the aligned interference channels of the interference base station,

wherein the interference channels comprise a first interference channel of a first terminal and a second interference channel of a second terminal, and

wherein the aligning the obtained interference channels in the same space comprises calculating a rank of the first interference channel and the second interference channel to have a value of 1 or a proximate value of 1.

16. The terminal device of claim 15, further comprising:

a feedback unit configured to feed back, to the serving base station, at least one of the aligned interference channels and a serving channel.

17. The terminal device of claim 15, wherein the interference channel alignment unit aligns, in the same space, the interference channels of the one or more terminal devices included in the cell edge region of the interference base station to be partially overlapped with each other.