Method for transceiving signal through at least two data streams in a wireless communication system

• US 9,986,451 B2
• Filed: 06/09/2014
• Issued: 05/29/2018
• Est. Priority Date: 06/07/2013
• Status: Active Grant

• Current Assignee: Industry Academic Cooperation Foundation, LG Electronics, Inc. (LG Corporation)
• Original Assignee: Industry Academic Cooperation Foundation, LG Electronics, Inc. (LG Corporation)
• Inventors: Chae, Hyukjin, Min, Byoung-Yoon, Kim, Kiyeon, Kim, Dong Ku
• Primary Examiner(s): Kincaid, Lester
• Assistant Examiner(s): Zewari, Sayed T
• Application Number:
  US14/299,676
• Publication Number:
  US 20140364133A1
• Time in Patent Office: 1,450 Days
• Field of Search: 455 6711, 455 6713, 4552261, 4552262, 4552263, 4552264, 455450, 455464, 455509, 455451, 4554521, 4554522, 455453, 455454, 4554261, 4554561
• CPC Class Codes: H04B 17/336 Signal-to-interference ratio [SIR] or carrier-to-interference ratio [CIR]
• 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 7/0626 Channel coefficients, e.g. channel state information [CSI]
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04W 24/08 Testing, supervising or monitoring using real traffic
• CPC Class Codes: H04W 72/54 based on quality criteria
• CPC Class Codes: H04W 72/541 using the level of interference

Abstract

A method is provided for transceiving a signal through at least two data streams in a wireless communication system. A first base station measures a wireless channel state for a link with a second base station by using an orthogonal pilot signal. The first base station receives channel status information related to a link of a first mobile station from the first mobile station, channel status information related to a link of a second mobile station from the second mobile station, and channel status information related to a device-to-device (D2D) link from the second mobile station. The D2D link is a channel link between the mobile stations. The first base station exchanges the received channel status information with the second base station, the first mobile station and the second mobile station using a broadcast signal, and determines data stream directions of the first base station and the second base station.

Claims

1. A method for transceiving a signal through at least two data streams in a wireless communication system supporting multi cells, the method performed by a first base station and comprising:

measuring a wireless channel state for a link with a second base station by using an orthogonal pilot signal;

receiving channel status information related to a link of a first mobile station from the first mobile station;

receiving channel status information related to a link of a second mobile station from the second mobile station;

receiving channel status information related to a device-to-device (D2D) link from the second mobile station,

wherein the D2D link is a channel link between the first mobile station and the second mobile station;

exchanging the received channel status information with the second base station, the first mobile station and the second mobile station using a broadcast signal; and

determining data stream directions of the first base station and the second base station based on the exchanged channel status information, channel state quality information of the data streams, fixed-rate coding information and information related to a sum-rate of the fixed-rate coding information.

2. The method of claim 1, wherein the D2D link is controlled by the first base station or the second base station.

3. The method of claim 1, wherein a frequency used in the D2D link is equal to a frequency of a base station controlling the D2D link.

10. The method of claim 1, wherein the channel status information related to the D2D link is transmitted from the first mobile station to the second mobile station.

11. The method of claim 1, wherein the measuring the wireless channel state comprises:

receiving a reference signal for measuring a channel state of a wireless link related to the second base station from the second base station; and

transmitting channel status information of the wireless link to the second base station using a wired backhaul or a wireless backhaul.

12. The method of claim 11, wherein information related to the reference signal is predetermined between the first base station and the second base station.

13. The method of claim 12, wherein the information related to the reference signal comprises at least one of a period for transmitting the reference signal, a type of the reference signal or an antenna port number.

4. A method for transceiving a signal through at least two data streams in a wireless communication system supporting a device-to-device (D2D) communication, the method performed by a first mobile station and comprising:

measuring a channel state for one or more neighbor mobile stations by using a pilot signal;

exchanging the measured channel state information with the one or more neighbor mobile stations;

determining at least one pair of transmitting mobile station-receiving mobile station for a best D2D communication based on the exchanged channel state information;

randomly initiating data stream directions of the mobile stations in each pair of the mobile stations;

computing an interference reduction value Δ

_n at each pair of the mobile stations when any of the mobile stations fails a decoding of a data stream; and

updating the data stream directions of the mobile stations in each pair of the mobile stations by comparing the computed interference reduction value Δ

_n and a predetermined value.

5. The method of claim 4, wherein the interference reduction value Δ

_n is determined as follows;

Δ

_n=SINR(D)−

SINR(D_n),

where SINR denotes a Signal to Interference-plus-Noise Ratio, D_n denotes a direction of an n-th data stream, 0 represents a forward direction of a data stream and 1 represents a reverse direction of a data stream, and a complementary value of D_n is represented by D_n.

6. The method of claim 4, wherein the updating the data stream directions comprises:

when the interference reduction value Δ

_n is greater than or equal to the predetermined value, the data stream directions of the mobile stations in each pair of the mobile stations are changed to an opposite direction; and

when the interference reduction value Δ

_n is smaller than the predetermined value, the data stream directions of the mobile stations in each pair of the mobile stations are not changed to the opposite direction.

7. The method of claim 4, wherein the predetermined value is 0.

8. The method of claim 4, further comprising:

transmitting a state value of the updated data stream directions to one or more neighbor mobile stations.

9. The method of claim 4, further comprising:

changing the data stream directions a predetermined number of times;

turning off a data stream of a mobile station when a decoding of the data stream of the mobile station fails when the changing the data stream directions are executed by the predetermined number of times;

checking whether data streams of the one or more neighbor mobile stations are all successful for decoding through binary feedback information; and

deactivating the data stream of the mobile station when any one of the data streams of the one or more neighbor mobile stations is successful for decoding as a result of the checking.