Method for power headroom reporting and device therefor
The present invention relates to a wireless communication system. More specifically, the present invention relates to a method and a device for transmitting a power headroom reporting in the wireless communication system, the method comprising: generating a PHR MAC CE (Power Headroom Reporting MAC Control Element) to be transmitted to the first BS; and transmitting a power headroom reporting through the PHR MAC CE to the first BS, wherein the PHR MAC CE includes only first PH (Power Headroom) information for activated cells served by the first BS such that second PH information for activated cells served by the second BS is not included.
1. A method for operating a User Equipment (UE) connected with a first Base Station (BS) and a second BS in a wireless communication system, the method comprising:
generating a Power Headroom Reporting (PHR) Medium Access Control (MAC) Control Element (CE) when PHR to be transmitted to the first BS is triggered, wherein a primary cell (PCell) is not served by the first BS,
wherein a first serving cell, which is served by the first BS, and a second serving cell are activated in the UE; and
transmitting a MAC Protocol Data Unit (PDU) including the generated PHR MAC CE to the first BS,
wherein when the second serving cell is served by the first BS, the PHR MAC CE includes Power Headroom (PH) information for the PCell, PH information for the first serving cell and PH information for the second serving cell,
wherein when the second serving cell is not served by the first BS, the PHR MAC CE includes the PH information for the PCell and the PH information for the first serving cell without the PH information for the second serving cell, even though the second serving cell is activated.
2. The method according to claim 1 , wherein when the second serving cell is not served by the first BS, a value of a Ci field associated with the second serving cell in the PHR MAC CE is set to 0, even though the second serving cell is activated.
3. The method according to claim 1 , wherein a value of a Ci field associated with the first serving cell in the PHR MAC CE is set to 1.
4. The method according to claim 1 , wherein when the PHR MAC CE includes the PH information for the PCell, the PH information for the first serving cell and the PH information for the second serving cell, an octet containing a Type 2 PH field is included first after an octet indicating presence of PH per SCell and followed by an octet containing an associated P CMAX,c field, and the octet containing a Type 2 PH field is followed by an octet with a Type 1 PH field for the PCell, the first serving cell and the second serving cell, in ascending order based on the ServCellIndex.
5. The method according to claim 1 , wherein when the PHR MAC CE includes the PHR information for the PCell and the PH information for the first serving cell without the PH information for the second serving cell, an octet containing a Type 2 PH field is included first after an octet indicating presence of PH per SCell and followed by an octet containing an associated P CMAX,c field, and the octet containing a Type 2 PH field is followed by an octet with a Type 1 PH field for the PCell and the first serving cell.
6. A User Equipment (UE) connected with a first BS (base station) and a second BS, operating in a wireless communication, the UE comprising:
a receiver and a transmitter; and
a processor, operably coupled to the receiver and the transmitter, that:
generates a Power Headroom Reporting (PHR) Medium Access Control (MAC) Control Element (CE) when PHR to be transmitted to the first BS is triggered, wherein a primary cell (PCell) is not served by the first BS,
wherein a first serving cell, which is served by the first BS, and a second serving cell are activated in the UE, and
controls the transmitter to transmit a MAC Protocol Data Unit (PDU) including the generated PHR MAC CE to the first BS,
wherein when the second serving cell is served by the first BS, the PHR MAC CE includes Power Headroom (PH) information for the PCell, PH information for the first serving cell and PH information for the second serving cell, and
wherein when the second serving cell is not served by the first BS, the PHR MAC CE includes the PH information for the PCell and the PH information for the first serving cell without the PH information for the second serving cell, even though the second serving cell is activated.
7. The UE according to claim 6 , wherein when the second serving cell is not served by the first BS, a value of a Ci field associated with the second serving cell in the PHR MAC CE is set to 0, even though the second serving cell is activated.
8. The UE according to claim 6 , wherein a value of a Ci field associated with the first serving cell in the PHR MAC CE is set to 1.
9. The UE according to claim 6 , wherein when the PHR MAC CE includes the PHR information for the PCell, the PH information for the first serving cell and the PH information for the second serving cell, an octet containing a Type 2 PH field is included first after an octet indicating presence of PH per SCell and followed by an octet containing an associated PCMAX,c field, and the octet containing a Type 2 PH field is followed by an octet with a Type 1 PH field for the PCell, the first serving cell and the second serving cell, in ascending order based on the ServCellIndex.
10. The UE according to claim 6 , wherein when the PHR MAC CE includes the PHR information for the PCell, and the PH information for the first serving cell without the PH information for the second serving cell, an octet containing a Type 2 PH field is included first after an octet indicating presence of PH per SCell and followed by an octet containing an associated PCMAX,c field, and the octet containing a Type 2 PH field is followed by an octet with a Type 1 PH field for the PCell and the first serving cell.