CONTROLLING POWER IN NON-LICENSED BAND

• US 20170223643A1
• Filed: 04/20/2017
• Published: 08/03/2017
• Est. Priority Date: 05/15/2014
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: AHN, Joonkui, KIM, Byounghoon, YANG, Suckchel, SEO, Hanbyul, YI, Yunjung
• Granted Patent: US 9,838,983 B2
• Time in Patent Office: Days
• CPC Class Codes: H04W 52/146 Uplink power control
• CPC Class Codes: H04W 52/34 TPC management, i.e. sharing limited amount of power among users or channels or data types, e.g. cell loading
• CPC Class Codes: H04W 52/365 Power headroom reporting
• CPC Class Codes: H04W 52/38 TPC being performed in particular situations
• CPC Class Codes: H04W 72/0446 Resources in time domain, e.g. slots or frames

Abstract

Provided are a method and an apparatus for controlling transmission power in a wireless communication system. A wireless device is connected to a first serving cell utilizing a licensed band and a second serving cell utilizing a non-licensed band. The transmission power from the second serving cell is determined by considering the clear channel assessment (CCA) coverage of the wireless device or the second serving cell.

Claims

1. A method for reporting a power headroom in a wireless communication system, the method performed by a user equipment (UE) comprising:

determining a power headroom of a scheduled subframe when a physical uplink shared channel (PUSCH) transmission on a Licensed-Assisted Access (LAA) secondary cell is scheduled in the scheduled subframe; and

reporting the power headroom of the scheduled subframe,

wherein the power headroom of the scheduled subframe is determined assuming that the UE performs the PUSCH transmission on the LAA secondary cell in the scheduled subframe irrespective of whether the UE can access the LAA secondary cell for the PUSCH transmission in the scheduled subframe according to a channel access procedure.

2. The method of claim 1, further comprising:

determining a maximum uplink transmit power in the scheduled subframe,

wherein the maximum uplink transmit power is determined assuming that the UE performs the PUSCH transmission on the LAA secondary cell in the scheduled subframe irrespective of whether the UE can access the LAA secondary cell for the PUSCH transmission in the scheduled subframe according to the channel access procedure.

3. The method of claim 1, wherein the power headroom is reported in a medium access control (MAC) control element (CE).

4. The method of claim 1, wherein the power headroom of the scheduled subframe is determined based on a bandwidth used for the PUSCH transmission on the LAA secondary cell.

5. A device for reporting a power headroom in a wireless communication system, the device comprising:

a radio frequency (RF) unit configured to receive and transmit radio signals; and

a processor operatively coupled with the RF unit and configured to;

determine a power headroom of a scheduled subframe when a physical uplink shared channel (PUSCH) transmission on a Licensed-Assisted Access (LAA) secondary cell is scheduled in the scheduled subframe; and

control the RF unit to report the power headroom of the scheduled subframe,

wherein the power headroom of the scheduled subframe is determined assuming that the UE performs the PUSCH transmission on the LAA secondary cell in the scheduled subframe irrespective of whether the UE can access the LAA secondary cell for the PUSCH transmission in the scheduled subframe according to a channel access procedure.

6. The device of claim 5, wherein the processor is configured to determine a maximum uplink transmit power in the scheduled subframe,

wherein the maximum uplink transmit power is determined assuming that the UE performs the PUSCH transmission on the LAA secondary cell in the scheduled subframe irrespective of whether the UE can access the LAA secondary cell for the PUSCH transmission in the scheduled subframe according to the channel access procedure.

7. The device of claim 5, wherein the power headroom is reported in a medium access control (MAC) control element (CE).

8. The device of claim 5, wherein the power headroom of the scheduled subframe is determined based on a bandwidth used for the PUSCH transmission on the LAA secondary cell.