Search

EP-4738947-A2 - METHOD AND APPARATUS FOR TRANSMITTING POWER HEADROOM REPORT BY USER EQUIPMENT IN WIRELESS COMMUNICATION SYSTEM

EP4738947A2EP 4738947 A2EP4738947 A2EP 4738947A2EP-4738947-A2

Abstract

A method for transmitting a power headroom report (PHR) by a user equipment (UE) in a wireless communication system is disclosed. The method comprises steps of selecting a first power headroom value among power headroom values for two or more Transmission and Reception Points (TRPs) of a serving cell belonging to a first cell group configured with two PHR mode; generating the PHR including the first power headroom value; transmitting the PHR to a network through a second cell group not configured with the two PHR mode, wherein the first power headroom value is related to a TRP on which a real transmission occurs among the two or more TRPs.

Inventors

  • LEE, Hanul
  • LEE, SUNYOUNG

Assignees

  • LG Electronics Inc.

Dates

Publication Date
20260506
Application Date
20230201

Claims (11)

  1. A method comprising: based on an uplink, UL, resource being allocated for a new transmission, determining, by a first medium access control, MAC, entity of a user equipment, UE, that: i) the first MAC entity is not configured with two power headroom report, PHR, mode, ii) a serving cell is configured with multiple Transmission and Reception Points, TRPs, and iii) a second MAC entity of the UE, to which the serving cell belongs, is configured with two PHR mode; based on determining and based on there being a real transmission, obtaining, by the first MAC entity, a first power headroom value related to the multiple TRPs for the serving cell from a power headroom value of the real transmission; based on determining and based on there not being the real transmission, obtaining, by the first MAC entity, a second power headroom value related to the multiple TRPs for the serving cell from a power headroom value related to a lowest index; and transmitting, by the first MAC entity, a PHR MAC control element, CE, including the first power headroom value or the second power headroom value for the serving cell.
  2. The method of claim 1, wherein the PHR MAC CE further includes a power headroom value for another serving cell belonging to the first MAC entity not configured with two PHR mode.
  3. The method of claim 2, wherein the power headroom value for the serving cell and the power headroom value for another serving cell are included in the PHR MAC CE in ascending order of a serving cell index.
  4. The method of any one of claims 1 to 3, wherein the first MAC entity and the second MAC entity are configured for different cell groups.
  5. The method of any one of claims 1 to 4, further comprising: receiving configuration information related to a first cell group associated with the first MAC entity and a second cell group associated with the second MAC entity, wherein the configuration information includes information related to two PHR mode.
  6. A user equipment, UE, comprising: at least one processor; and at least one computer memory storing instructions that, when executed by the at least one processor, cause the UE to perform operations comprising: based on an uplink, UL, resource being allocated for a new transmission, determining, by a first medium access control, MAC, entity of the UE, that: i) the first MAC entity is not configured with two power headroom report, PHR, mode, ii) a serving cell is configured with multiple Transmission and Reception Points, TRPs), and iii) a second MAC entity of the UE, to which the serving cell belongs, is configured with two PHR mode; based on determining and based on there being a real transmission, obtaining, by the first MAC entity, a first power headroom value related to the multiple TRPs for the serving cell from a power headroom value of the real transmission; based on determining and based on there not being the real transmission, obtaining, by the first MAC entity, a second power headroom value related to the multiple TRPs for the serving cell from a power headroom value related to a lowest index; and transmitting, by the first MAC entity, a PHR MAC control element, CE, including the first power headroom value or the second power headroom value for the serving cell.
  7. The UE of claim 6, wherein the PHR MAC CE further includes a power headroom value for another serving cell belonging to the first MAC entity not configured with two PHR mode.
  8. The UE of claim 7 wherein the power headroom value for the serving cell and the power headroom value for another serving cell are included in the PHR in ascending order of a serving cell index.
  9. The UE of any one of claims 6 to 8, wherein the first MAC entity and the second MAC entity are configured for different cell groups.
  10. The UE of any one of claims 6 to 9, wherein the operations further comprise: receiving configuration information related to a first cell group associated with the first MAC entity and a second cell group associated with the second MAC entity, wherein the configuration information includes information related to two PHR mode.
  11. A non-transitory computer-readable storage medium comprising program instructions that, when executed by at least one processor, cause a User Equipment, UE, to perform operations comprising: based on an uplink, UL, resource being allocated for a new transmission, determining, by a first medium access control, MAC, entity of the UE, that: i) the first MAC entity is not configured with two power headroom report, PHR, mode, ii) a serving cell is configured with multiple Transmission and Reception Points, TRPs), and iii) a second MAC entity of the UE, to which the serving cell belongs, is configured with two PHR mode; based on determining and based on there being a real transmission, obtaining, by the first MAC entity, a first power headroom value related to the multiple TRPs for the serving cell from a power headroom value of the real transmission; based on determining and based on there not being the real transmission, obtaining, by the first MAC entity, a second power headroom value related to the multiple TRPs for the serving cell from a power headroom value related to a lowest index; and transmitting, by the first MAC entity, a PHR MAC control element, CE, including the first power headroom value or the second power headroom value for the serving cell.

Description

BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a wireless communication system, and more particularly, to a method for transmitting a Power Headroom Report (PHR) by a user equipment (UE) in a wireless communication system and an apparatus therefor. Discussion of the Related Art Introduction of new radio communication technologies has led to increases in the number of user equipments (UEs) to which a base station (BS) provides services in a prescribed resource region, and has also led to increases in the amount of data and control information that the BS transmits to the UEs. Due to typically limited resources available to the BS for communication with the UE(s), new techniques are needed by which the BS utilizes the limited radio resources to efficiently receive/transmit uplink/downlink data and/or uplink/downlink control information. In particular, overcoming delay or latency has become an important challenge in applications whose performance critically depends on delay/latency. SUMMARY OF THE INVENTION Accordingly, the present disclosure is directed to a method for transmitting a Power Headroom Report (PHR) by a user equipment (UE) in a wireless communication system and an apparatus therefor, which substantially obviate one or more problems due to limitations and disadvantages of the related art. Additional advantages, objects, and features of the specification will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the specification. The objectives and other advantages of the specification may be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings. A method for transmitting a power headroom report (PHR) by a user equipment (UE) in a wireless communication system according to the embodiment of the present invention comprises the steps of selecting a first power headroom value among power headroom values for two or more Transmission and Reception Points (TRPs) of a serving cell belonging to a first cell group configured with two PHR mode; generating the PHR including the first power headroom value; transmitting the PHR to a network through a second cell group not configured with the two PHR mode, wherein the first power headroom value is related to a TRP on which a real transmission occurs among the two or more TRPs. Further, a user equipment (UE) in a wireless communication system according to the present invention comprises at least one transceiver; at least one processor; and at least one computer memory operably connectable to the at least one processor and storing instructions that, when executed, cause the at least one processor to perform operations comprising: selecting a first power headroom value among power headroom values for two or more Transmission and Reception Points (TRPs) of a serving cell belonging to a first cell group configured with two power headroom report (PHR) mode; generating a PHR including the first power headroom value; transmitting the PHR to a network through a second cell group not configured with the two PHR mode, wherein the first power headroom value is related to a TRP on which a real transmission occurs among the two or more TRPs. Preferably, the UE may calculate the first power headroom value related to a first TRP and a second power headroom value related to a second TRP, wherein the first TRP has a lower index of the second TRP Preferably, a second power headroom value for a serving cell belonging to the second cell group not configured with the two PHR mode may be obtained. The PHR further includes the second power headroom value. More preferably, the first power headroom value and the second power headroom value is included in the PHR in ascending order of a serving cell index. More preferably, another PHR to be transmitted through the first cell group configured with the two PHR mode includes all of the power headroom values for the two or more TRPs of the serving cell belonging to the first cell group and the second power headroom value. It will be appreciated by persons skilled in the art that the effects that can be achieved through the present invention are not limited to what has been particularly described hereinabove and other advantages of the present invention will be more clearly understood from the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates an example of a communication system to which implementations of the present disclosure is applied;FIG. 2 is a block diagram illustrating examples of communication devices which can perform a method according to the present disclosure;FIG. 3 illustrates another example of a wireless device which can perform implementations of the present invention;FIG. 4 illustrates an example of protocol stacks in a third