# US 12,772,166 B2 · Method and apparatus for saving power consumption of base station in communication system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,772,166 B2 - Document ID: US12772166B2 - Status: Granted - Kind: B2 - Application number: 18/490,333 - Filed: 2023-10-19 - Published: 2024-04-25 - Granted: 2026-10-20 - Earliest claimed: 2022-10-24 - Assignees: Electronics and Telecommunications Research Institute - Applicants: Electronics and Telecommunications Research Institute - Inventors: Jae Su Song; Hee Sang Chung - Web page: https://patentgrep.com/patent/US12772166B2 ## CPC - H04W 52/0206: {in access points, e.g. base stations} - H04W 36/165: {for reducing network power consumption (H04W36/18 - H04W36/22 take precedence)} - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract A method of a first base station may comprise: determining, by a MT of the first base station, whether there is a terminal connected to a BSU of the first base station, when a power-off condition is satisfied in the BSU; instructing, by the MT, the terminal, which is connected to the BSU, to be handed over to a second base station, when there is a terminal connected to the BSU; instructing, by the MT, the BSU to power off the BSU, when the handover of the terminal, which is connected to the BSU, is completed; and transmitting, by the MT, a first message, which indicates a power-off state of the first base station, to the second base station, when the BSU is powered off. ## Claims ### Claim 1 A method of a first base station including a mobile terminal (MT) and a base station unit (BSU), the method comprising: determining, by the MT of the first base station, whether there is a terminal connected to the BSU of the first base station, when a power-off condition is satisfied in the BSU; instructing, by the MT, the terminal, which is connected to the BSU, to be handed over to a second base station, when there is a terminal connected to the BSU; instructing, by the MT, the BSU to power off the BSU, when the handover of the terminal, which is connected to the BSU, is completed; and transmitting, by the MT, a first message, which indicates a power-off state of the first base station, to the second base station, when the BSU is powered off, wherein a full coverage of the first base station partly overlaps with a coverage of the second base station, and wherein the BSU uses a first frequency, and the second base station uses a second frequency. ### Claim 2 (depends on 1) The method of claim 1, wherein messages delivered between the MT and the second base station are delivered through a control link using the second frequency resource, a connection of the control link to a core network is blocked, and the control link is connected to the second base station. ### Claim 3 (depends on 2) The method of claim 2, wherein the control link is established by an access stratum (AS) layer. ### Claim 4 (depends on 2) The method of claim 2, further comprising temporarily suspending, by the MT, the connection of the control link, based on a second message indicating a base station power state report confirmation received from the second base station. ### Claim 5 (depends on 1) The method of claim 1, wherein a RRC connection of the MT with the second base station is in RRC_INACTIVE state. ### Claim 6 (depends on 1) The method of claim 1, wherein the power off condition is satisfied when a sum of data transmission rates of terminals connected to the BSU is equal to or smaller than a threshold. ### Claim 7 (depends on 1) The method of claim 1, further comprising instructing, by the MT, the BS to immediately power off the BSU, when the power off condition is satisfied, and there is no terminal connected to the BS. ### Claim 8 (depends on 1) The method of claim 1, further comprising: receiving discontinuous reception (DRX) setting information and paging setting information from the second base station; monitoring, by the MT, a paging initiated from the second base station, based on the received DRX setting information and paging setting information; and performing, by the MT, a base station power on procedure of turning on a power of the BSU, when a paging message is received from the second base station. ### Claim 9 A method of a first base station, the method comprising: determining whether there is a second base station in a power-off state, which belongs to a first area in a cell coverage of the first base station which is set by a plurality of areas, when a user equipment (UE) activity in the first area exceeds a threshold; transmitting a first message, which indicates a power-on of the second base station, to the second base station, when there is the second base station; receiving a second message, which indicates that the second base station is in a power-on state, from the second base station; and initiating a handover procedure to allow a terminal, which is located in the first area and is connected to the first base station, to be handed over to the second base station, wherein the first base station uses a first frequency, and the second base station uses a second frequency, and wherein the second base station includes a mobile terminal (MT) and a base station unit (BSU), the first message is a paging message transmitted to the MT of the second base station, and the MT controls the BSU of the second base station to power on the BSU based on the first message. ### Claim 10 (depends on 9) The method of claim 9, wherein messages delivered between the first base station and the second base station are delivered through a control link using the first frequency resource, a connection of the control link to a core network is blocked, and the control link is connected to the second base station. ### Claim 11 (depends on 10) The method of claim 10, wherein the control link is established by an access stratum (AS) layer. ### Claim 12 (depends on 10) The method of claim 10, wherein the receiving of the second message further includes transmitting a third message, which indicates temporary suspension of the connection of the control link, to the second base station. ### Claim 13 (depends on 9) The method of claim 9, wherein the UE activity is a sum of data transmission rates of terminals which are located in the first area and are connected to the base station. ### Claim 14 A first base station comprising a processor, wherein the processor causes the first base station to: determine whether there is a second base station in a power-off state, which belongs to a first area in a cell coverage of the first base station which is set by a plurality of areas, when a user equipment (UE) activity in the first area exceeds a threshold; transmit a first message, which indicates a power-on of the second base station, to the second base station, when there is the second base station; receive a second message, which indicates that the second base station is in a power-on state, from the second base station; and initiate a handover procedure to allow a terminal, which is located in the first area and is connected to the first base station, to be handed over to the second base station, wherein the first base station uses a first frequency, and the second base station uses a second frequency, and wherein the second base station includes a mobile terminal (MT) and a base station unit (BSU), the first message is a paging message transmitted to the MT of the second base station, and the MT controls the BSU of the second base station to power on the BSU based on the first message. ### Claim 15 (depends on 14) The first base station of claim 14, wherein messages delivered between the first base station and the second base station are delivered through a control link using the first frequency resource, a connection of the control link to a core network is blocked, and the control link is connected to the second base station. ### Claim 16 (depends on 15) The first base station of claim 15, wherein the control link is established by an access stratum (AS) layer. ### Claim 17 (depends on 15) The first base station of claim 15, wherein the receiving of the second message further causes the first base station to transmit a third message, which indicates temporary suspension of the connection of the control link, to the second base station. ### Claim 18 (depends on 14) The first base station of claim 14, wherein the UE activity is a sum of data transmission rates of terminals which are located in the first area and are connected to the base station.