Method and device for transmitting channel state information in wireless access system supporting machine type communication

Patent metadata

Field	Value
Publication number	US-2016285535-A1
Application number	US-201414915028-A
Country	US
Kind code	A1
Filing date	Aug 29, 2014
Priority date	Aug 29, 2013
Publication date	Sep 29, 2016
Grant date	—

Abstract

The present invention provide a method by which a terminal measures channel state information (CSI), a method by which a terminal transmits CSI, and devices for supporting the methods. A method by which a terminal feeds back CSI in a wireless access system, according to one embodiment of the present invention, can comprise the steps of: receiving an upper layer signal including a channel quality indicator (CQI) index; receiving a physical downlink control channel (PDCCH) signal including an aperiodic CSI request field; receiving a physical downlink shared channel (PDSCH) signal that is repeatedly transmitted as many time as the number indicated by the CQI index; measuring the CSI for a CSI reference resource; and feeding back the measured CSI by using a physical uplink shared channel (PUSCH) signal.

First claim

1 . A method for feeding back Channel State Information (CSI) by a User Equipment (UE) in a wireless access system, the method comprising:
receiving a higher layer signal including a Channel Quality Indicator (CQI) index; receiving a Physical Downlink Control Channel (PDCCH) signal including an aperiodic CSI request field; receiving a Physical Downlink Shared Channel (PDSCH) signal transmitted repeatedly as many times as a number indicated by the CQI index; measuring CSI in a CSI reference resource; and feeding back the measured CSI using a Physical Uplink Shared Channel (PUSCH) signal.

2 . The method according to claim 1 , wherein the CQI index is mapped to a modulation scheme, a coding rate, a coding efficiency, and a repetition number of the PDSCH signal.

3 . The method according to claim 2 , wherein the CQI index is included in a CQI table including only Quadrature Phase Shift Keying (QPSK).

4 . The method according to claim 1 , wherein the PUSCH signal is transmitted repeatedly a predetermined number of times.

5 . The method according to claim 1 , wherein the PDCCH signal is transmitted repeatedly a predetermined number of times.

6 . The method according to claim 5 , wherein the repetition number is equal to the number indicated by the CQI index.

7 . The method according to claim 1 , wherein the step of the measuring of CSI is performed by using a plurality of CSI reference resources.

8 . The method according to claim 1 , wherein the CSI reference resource is configured with respect to a last reception time of the repeatedly transmitted PDSCH signal.

9 . A User Equipment (UE) for feeding back Channel State Information (CSI) in a wireless access system, the UE comprising:
a transmitter; a receiver; and a processor configured to feed back CSI in conjunction with the transmitter and the receiver, wherein the processor receives a higher layer signal including a Channel Quality Indicator (CQI) index, receives a Physical Downlink Control Channel (PDCCH) signal including an aperiodic CSI request field, and receives a Physical Downlink Shared Channel (PDSCH) signal transmitted repeatedly as many times as a number indicated by the CQI index, by controlling the receiver, measures CSI in a CSI reference resource, and feeds back the measured CSI using a Physical Uplink Shared Channel (PUSCH) signal by controlling the transmitter.

10 . The UE according to claim 9 , wherein the CQI index is mapped to a modulation scheme, a coding rate, a coding efficiency, and a repetition number of the PDSCH signal.

11 . The UE according to claim 10 , wherein the CQI index is included in a CQI table including only Quadrature Phase Shift Keying (QPSK).

12 . The UE according to claim 9 , wherein the PUSCH signal is transmitted repeatedly a predetermined number of times.

13 . The UE according to claim 9 , wherein the PDCCH signal is transmitted repeatedly a predetermined number of times.

14 . The UE according to claim 13 , wherein the repetition number is equal to the number indicated by the CQI index.

15 . The UE according to claim 9 , wherein the CSI is measured by using a plurality of CSI reference resources.

16 . The UE according to claim 9 , wherein the CSI reference resource is configured with respect to a last reception time of the repeatedly transmitted PDSCH signal.

Assignees

• Lg Electronics Inc

Inventors

• Kim Bonghoe
• Yang Suckchel
• Ahn Joonkui
• Seo Dongyoun

Classifications

• H04W72/23

  in the downlink direction of a wireless link, i.e. towards a terminal · CPC title

• H04B17/309

  Measuring or estimating channel quality parameters · CPC title

• H04B7/0626 Primary

  Channel coefficients, e.g. channel state information [CSI] · CPC title

• H04W4/005

  Electricity · mapped topic

• H04W72/042

  Electricity · mapped topic