METHOD FOR REPORTING CHANNEL STATE INFORMATION IN WIRELESS COMMUNICATION SYSTEM AND APPARATUS THEREFOR

• US 20190081678A1
• Filed: 09/10/2018
• Published: 03/14/2019
• Est. Priority Date: 09/08/2017
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: PARK, Haewook, KIM, Kijun, KANG, Jiwon, YOON, Sukhyon
• Granted Patent: US 10,812,164 B2
• Time in Patent Office: Days
• CPC Class Codes: H04B 7/0486 taking channel rank into account
• CPC Class Codes: H04B 7/0626 Channel coefficients, e.g. channel state information [CSI]
• CPC Class Codes: H04B 7/065 Variable contents, e.g. long-term or short-short
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/0051 of dedicated pilots, i.e. pilots destined for a single user or terminal
• CPC Class Codes: H04W 72/21 in the uplink direction of a wireless link, i.e. towards the network
• CPC Class Codes: H04W 72/56 based on priority criteria

Abstract

Provided are a method and an apparatus for reporting channel state information (CSI) by a user equipment in a wireless communication system. According to the present invention, the user equipment may receive configuration information related with the CSI from a base station and measure the CSI based on the configuration information. Thereafter, the user equipment includes reporting the CSI to the base station and the CSI includes a rank indicator (RI), a channel quality indicator (CQI), and an indicator indicating the number of amplitude coefficients other than 0 and the second part includes a precoding matrix indicator (PMI).

Claims

1. A method for reporting, by a user equipment, channel state information (CSI) in a wireless communication system, the method comprising:

receiving configuration information related with the CSI from a base station;

measuring the CSI based on the configuration information; and

reporting the CSI to the base station,

wherein the CSI is comprises a first part and a second part,

wherein the first part includes a rank indicator (RI), a channel quality indicator (CQI), and an indicator indicating the number of amplitude coefficients other than 0, and

wherein the second part includes a precoding matrix indicator (PMI).

2. The method of claim 1, wherein a payload size of the second part is determined by the first part.

3. The method of claim 2, wherein a bitwidth of the PMI is determined based on the rank indicator and the indicator.

4. The method of claim 1, wherein the CSI is transmitted on a physical uplink shared channel (PUSCH), and

transmission power of the CSI increases as the number of bits of the first part increases.

5. The method of claim 1, wherein the rank indicator, the channel quality indicator, and the indicator are each encoded through a same coding rate with separate field in the first part.

6. The method of claim 1, wherein the indicator is independently indicated for each layer.

7. The method of claim 6, wherein the number of bits of the indicator is configured for each layer by the following equation when L which is a codebook configuration parameter indicated by higher layer signaling indicates the number of base vectors linearly coupled in a linear coupling based codebook.

┌

log₂(2L−

1)┐

8. The method of claim 1,

wherein the first part has a higher CSI priority than the second part, and

wherein the first part and the second part are mapped to a symbol next a symbol to which a demodulation reference signal (DMRS) is mapped according to the CSI priority.

9. The method of claim 8, wherein the first part and the second part are sequentially mapped in a direction in which an index of the symbol to which the DMRS is mapped increases.

10. The method of claim 1, wherein the number of symbols to which the first part is mapped is determined based on the number of bits of the first part and the number of bits of the second part.

11. The method of claim 1, wherein the first part and the second parts are encoded according to different modulation orders and/or coding rates, respectively.

12. The method of claim 1,

wherein the first part and the second part are transmitted through different transmission powers, and

wherein specific values of the first part and/or the second part are/is repeatedly transmitted.

13. A user equipment for reporting channel state information (CSI) in a wireless communication system, the user equipment comprising:

a radio frequency (RF) module transmitting and receiving a radio signal; and

a processor controlling the RF module,

wherein the processor

receives configuration information related with the CSI from a base station,

measures the CSI based on the configuration information, and

reports the CSI to the base station,

wherein the CSI is comprises by a first part and a second part,

wherein the first part includes a rank indicator (RI), a channel quality indicator (CQI), and an indicator indicating the number of amplitude coefficients other than 0, and

wherein the second part includes a precoding matrix indicator (PMI).