METHOD FOR PERFORMING PRE-CODING USING CODEBOOK IN WIRELESS COMMUNICATION SYSTEM AND APPARATUS THEREFOR

• US 20170373745A1
• Filed: 12/18/2015
• Published: 12/28/2017
• Est. Priority Date: 12/30/2014
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation), Sogang University Research Foundation
• Original Assignee: Sogang University Research Foundation
• Inventors: PARK, Jonghyun, KANG, Hosik, SUH, Junyeub, SUNG, Wonjin, KIM, Kijun
• Granted Patent: US 10,142,004 B2
• Time in Patent Office: Days
• 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 7/0456 Selection of precoding matrices or codebooks, e.g. using matrices antenna weighting
• CPC Class Codes: H04B 7/0469 taking special antenna structures, e.g. cross polarized antennas into account
• CPC Class Codes: H04B 7/0478 Special codebook structures directed to feedback optimisation
• CPC Class Codes: H04B 7/0639 Using selective indices, e.g. of a codebook, e.g. pre-distortion matrix index [PMI] or for beam selection
• CPC Class Codes: H04L 25/0224 using sounding signals
• CPC Class Codes: H04L 25/03343 Arrangements at the transmitter end
• CPC Class Codes: H04L 5/001 the frequencies being arranged in component carriers
• CPC Class Codes: H04L 5/005 of common pilots, i.e. pilots destined for multiple users or terminals
• CPC Class Codes: H04L 5/0051 of dedicated pilots, i.e. pilots destined for a single user or terminal

Abstract

A method for performing, by a UE, precoding using a codebook in a wireless communication system includes: receiving a reference signal for channel estimation from an eNB; estimating a channel through the received reference signal; determining a precoding matrix related to the estimated channel in a codebook; and feeding back, to the eNB, a precoding matrix index (PMI) corresponding to the determined precoding matrix, wherein the codebook is generated in consideration of at least one of a region to which the UE belongs and the position of the UE.

Claims

1. A method for performing, by a UE, precoding using a codebook in a wireless communication system, comprising:

receiving a reference signal for channel estimation from an eNB;

estimating a channel through the received reference signal;

determining a precoding matrix related to the estimated channel in a codebook; and

feeding back, to the eNB, a precoding matrix index (PMI) corresponding to the determined precoding matrix,

wherein the codebook is generated in consideration of at least one of a region to which the UE belongs and the position of the UE.

2. The method according to claim 1, wherein the region to which the UE belongs corresponds to one of M×

N regions generated by dividing a specific sector of the eNB into M regions in a first direction and N regions in a second direction.

3. The method according to claim 2, wherein different codebooks are used in the M×

N regions.

4. The method according to claim 1, wherein, when multiple codebooks are selected according to regions to which the UE belongs, the codebook is selected from the selected multiple codebooks in consideration of the position of the UE.

5. The method according to claim 1, wherein at least one of a channel phase difference and a channel correlation difference between neighbor antennas of the eNB is generated according to at least one of the region to which the UE belongs and the position of the UE.

6. The method according to claim 5, wherein the codebook is generated through selecting a quantization level for a first phase difference between neighbor antennas of the eNB and selecting a quantization level for a second phase difference on the basis of the selected quantization level for the first phase difference.

7. The method according to claim 6, wherein the quantization level for the first phase difference is selected in consideration of at least one of the region to which the UE belongs and the position of the UE.

8. The method according to claim 6, wherein the quantization level for the second phase difference is selected on the basis of predefined precoding matrix vector generation function or pattern information.

9. The method according to claim 1, further comprising transmitting a parameter related to an angular spread between the eNB and the UE to the eNB.

10. The method according to claim 9, wherein the codebook is selected in such a manner that a first codebook set is selected on the basis of the parameter related to the angular spread, a second codebook set is selected from the selected first codebook set on the basis of at least one of the region to which the UE belongs and the position of the UE, and one of the selected second codebook set is selected.

11. The method according to claim 6, wherein the angular spread is divided into an azimuth angular spread and a zenith angular spread.

12. The method according to claim 1, wherein the position of the UE is acquired through at least one of a PRS (Positioning Reference Signal) based OTDOA (Observed Time Difference Of Arrival) positioning method, a SRS (Sounding Reference Signal) based UTDOA (Uplink Time Difference Of Arrival) method, an A-GNSS (Assisted-Global Navigation Satellite Systems) method using a satellite/GPS and an RFPM (Radio Frequency Pattern Matching) method.

13. A UE for performing precoding using a codebook in a wireless communication system, comprising:

a radio frequency (RF) unit for transmitting and receiving radio signals; and

a processor functionally connected to the RF unit and controlling the UE,

wherein the processor is configured;

to receive a reference signal for channel estimation from an eNB;

to estimate a channel through the received reference signal;

to determine a precoding matrix related to the estimated channel in a codebook; and

to feed back, to the eNB, a precoding matrix index (PMI) corresponding to the determined precoding matrix,

wherein the codebook is generated in consideration of at least one of a region to which the UE belongs and the position of the UE.