Base station, control device, method and program

Abstract

A parent station device of a base station according to one aspect includes a processor (control unit) and a transceiver (communication unit), and the processor is configured to cause the transceiver to transmit power saving control information which is for reducing the power consumption of a child station device of the base station that wirelessly communicates with a user terminal. This configuration may provide a base station or the like that contributes to reduced power consumption.

Description

Base station, control device, communication system, method and program

[0001] The present disclosure relates to a base station, a control device, a communication system, a method, and a program.

[0002] Technologies for improving power efficiency in mobile communications are advancing. For example, Patent Literature 1 describes a technique in which a terminal device communicating with a base station device replaces a portion of an Orthogonal Frequency-Division Multiplexing (OFDM) signal with a predetermined number of consecutive zeros and transmits the signal. It is possible to set the transmission power to be reduced for at least a portion of the portion replaced with zeros.

[0003] Furthermore, Patent Document 2 describes that a terminal device communicating with a base station device sets the start position of an OFDM symbol in an initial partial subframe for an LAA (Licensed Assisted Access) cell, where some subframes in the LAA indicate that no signal is transmitted.

[0004] International Publication No. 2020 / 175039 Japanese Patent Application Laid-Open No. 2019-016824

[0005] One object of the present disclosure is to provide a base station, a control device, a communication system, a method, and a program that contribute to reducing power consumption. It should be noted that this object is only one of multiple objects that multiple embodiments disclosed in this specification aim to achieve. Other objects or problems and novel features will become apparent from the description of this specification or the accompanying drawings.

[0006] In one embodiment, a base station parent station device includes a processor and a transceiver, and the processor is configured to cause the transceiver to transmit power saving control information for reducing the power consumption of the base station child station device that wirelessly communicates with a user terminal.

[0007] A control device according to one embodiment includes a processor and a transceiver, and the processor is configured to cause the transceiver to transmit power saving control information for a base station having a wireless communication unit that wirelessly communicates with a user terminal, in order to reduce the power consumption of the wireless communication unit.

[0008] According to one aspect, a communication system includes a master station device of a base station and a slave station device of the base station. The master station device includes a first processor and a first transceiver, and the first processor is configured to cause the first transceiver to transmit power-saving control information for reducing power consumption of the slave station device that wirelessly communicates with a user terminal. The slave station device includes a second processor and a second transceiver, and the second processor is configured to cause the second transceiver to receive the power-saving control information from the master station device.

[0009] According to another aspect, a communication system includes a control device and a base station. The control device includes a first processor and a first transceiver, and the first processor is configured to cause the first transceiver to transmit power saving control information to the base station having a wireless communication unit that wirelessly communicates with a user terminal, for reducing power consumption of the wireless communication unit. The base station includes a second processor and a second transceiver, and the second processor is configured to cause the second transceiver to receive the power saving control information from the control device.

[0010] A method according to one aspect is a method executed by a master station device of a base station, which includes transmitting power saving control information for reducing power consumption of a slave station device of the base station that wirelessly communicates with a user terminal.

[0011] Another aspect of the method is a method executed by a control device, which includes transmitting power saving control information to a base station having a wireless communication unit that wirelessly communicates with a user terminal, for reducing power consumption of the wireless communication unit.

[0012] According to one aspect, the program causes a computer to transmit power saving control information for reducing power consumption of a slave station device of a base station that wirelessly communicates with a user terminal.

[0013] Another aspect of the program is a program that causes a computer to execute the following: transmitting power saving control information for a base station having a wireless communication unit that communicates wirelessly with a user terminal, to reduce the power consumption of the wireless communication unit.

[0014] According to the present disclosure, it is possible to provide a base station, a control device, a communication system, a method, and a program that contribute to reducing power consumption.

[0015] 1 is a block diagram showing an example configuration of a base station according to the present disclosure. FIG. 2 is a sequence diagram showing an example operation of a master station device according to the present disclosure. FIG. 3 is a block diagram showing an example configuration of a control device according to the present disclosure. FIG. 4 is a sequence diagram showing an example operation of a control device according to the present disclosure. FIG. 5 is a block diagram showing an example configuration of a communication system according to the present disclosure. FIG. 6 is a graph showing an example transition of cell traffic and an energy saving status IE. FIG. 7 is a graph showing an example transition of cell radio resource usage and an energy saving status IE. FIG. 8 is a sequence diagram showing an example operation of a communication system according to the present disclosure. FIG. 9 is a block diagram showing an example configuration of a communication system according to the present disclosure. FIG. 10 is a sequence diagram showing an example operation of a communication system according to the present disclosure. FIG. 11 is a block diagram showing an example configuration of a communication system according to the present disclosure. FIG. 12 is a block diagram showing an example configuration of a communication system according to the present disclosure. FIG. 13 is a block diagram showing an example configuration of a communication system according to the present disclosure. FIG. 14 is a block diagram showing an example configuration of a communication system according to the present disclosure.

[0016] Each embodiment will be described below with reference to the drawings. Note that the following description and drawings have been omitted and simplified as appropriate for clarity of explanation. Furthermore, in the following drawings, the same elements are given the same reference numerals, and duplicate explanations are omitted as necessary. It goes without saying that all or any part of the configuration described in each embodiment can be applied to the devices described in other embodiments as appropriate. Similarly, the drawings referenced for explanation in each embodiment can also be applied to other embodiments. Furthermore, in this disclosure, unless otherwise specified, when "at least any of" multiple items is defined, the definition may mean any one item among the multiple items, or any two or more items among the multiple items (including all items).

[0017] Embodiment 1 Hereinafter, embodiment 1 will be described with reference to the drawings. In this embodiment 1, a base station capable of reducing power consumption in a slave station device of the base station will be described. Note that the configuration and processing described below are examples and are not limited to these.

[0018] [Configuration Description] Fig. 1 is a block diagram showing an example of a base station. The base station B1 includes a master station device 10 and a slave station device 20 that is provided separately from the master station device 10. Although Fig. 1 shows only one slave station device 20, the base station B1 may include multiple slave station devices 20.

[0019] Furthermore, the slave station equipment 20 may be connected directly to the master station equipment 10, or may be connected via one or more relay equipment. A relay equipment is any device that relays communications. Furthermore, as will be described later, since the master station equipment 10 is upstream of the slave station equipment 20 in the communication system, the master station equipment 10 can also be expressed as a "higher-level device" and the slave station equipment 20 as a "lower-level device." The network between the master station equipment 10 and the slave station equipment 20 is also called a fronthaul.

[0020] The base station B1 may be provided as a base station in, for example, a fifth-generation mobile communication system (5G system). The fifth-generation mobile communication system is New Radio Access (NR), which is a fifth-generation radio access technology. However, the base station B1 is not limited to the fifth-generation mobile communication system, and may be a base station in a different mobile communication system, such as a fourth-generation mobile communication system (4G system; for example, a Long Term Evolution (LTE) system or an LTE-Advanced system) or a sixth-generation mobile communication system.

[0021] The base station B1 may be, for example, a gNodeB (gNB). The gNB is a node that terminates NR user plane and control plane protocols for a user equipment (UE) and connects to a 5G core network (5GC) via a Next Generation (NG) interface. As another example, the base station B1 may be an LTE evolved NodeB (ng-eNB). The ng-eNB is a node that terminates E-UTRA (Evolved Universal Terrestrial Radio Access) user plane and control plane protocols for a UE and connects to a 5GC via an NG interface.

[0022] Alternatively, the base station B1 may be a CU (Central Unit) in a C-RAN (Cloud Radio Access Network) configuration or a gNB-CU. The gNB-CU is a logical node that hosts the gNB's RRC (Radio Resource Control) protocol, SDAP (Service Data Adaptation Protocol) protocol, and PDCP (Packet Data Convergence Protocol) protocol. Alternatively, the gNB-CU is a logical node that hosts the en-gNB's RRC protocol and PDCP protocol, which controls the operation of one or more gNB-Distributed Units (gNB-DUs). The gNB-CU terminates the F1 interface connecting to the gNB-DU. Alternatively, the base station B1 may be a CP (Control Plane) Unit or a gNB-CU-CP (gNB-CU-Control Plane). The gNB-CU-CP is a logical node that hosts the RRC protocol and the control plane portion of the gNB-CU's PDCP protocol for the en-gNB or gNB. The gNB-CU-CP terminates the E1 interface connecting to the gNB-CU-UP (gNB-CU-User Plane) and the F1-C interface connecting to the gNB-DU. The gNB-CU-UP is a logical node that hosts the user plane part of the PDCP protocol of the gNB-CU for the en-gNB. The gNB-CU-UP terminates the E1 interface connecting to the gNB-CU-CP and the F1-U interface connecting to the gNB-DU.

[0023] Furthermore, the base station B1 may be an eNB or an eNB-CU. Furthermore, the base station B1 may be an EUTRAN (Evolved Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network) node or an NG-RAN (Next Generation Radio Access Network) node. The EUTRAN node may be an eNB or an en-gNB. The NG-RAN node may be a gNB or an ng-eNB. The en-gNB provides protocol termination of the NR user plane and control plane for the UE and operates as a secondary node in EN-DC (NR Dual Connectivity).

[0024] 1 , the master station device 10 includes a communication unit 11 and a control unit 12. The communication unit 11 and the control unit 12 may be software or modules that perform processing when a processor executes a program stored in a memory. Alternatively, the communication unit 11 and the control unit 12 may be hardware such as a circuit or a chip.

[0025] The communication unit 11 transmits and receives various information by connecting to and communicating with the slave station device 20 or the relay device. However, the communication unit 11 may also transmit and receive various information by connecting to and communicating with a control device or the like connected to a higher level of the base station B1. The communication unit 11 is, for example, a transceiver.

[0026] The control unit 12 reads and executes various information and programs stored in the memory to perform various processes of the master station device 10. The control unit 12 can also perform processing in accordance with at least one or all of the setting information, such as various information elements (IEs), various fields, and various conditions, contained in the message received by the communication unit 11. The control unit 12 is, for example, a processor.

[0027] The control unit 12 is configured to be able to execute at least one of a plurality of layer processes that can be executed by the base station, which may include a physical layer, a media access control (MAC) layer, a radio link control (RLC) layer, a PDCP layer, a radio resource control (RRC) layer, and a non-access stratum (NAS) layer.

[0028] The control unit 12 causes the communication unit 11 to transmit first power saving control information for reducing power consumption of the slave station device 20 that communicates wirelessly with the UE. Here, the first power saving control information may include, for example, an enable signal that indicates only whether power saving control is enabled or disabled, or may include detailed information indicating a detailed method for the slave station device 20 to save power.

[0029] The detailed information may include, for example, at least one of the following IEs: An IE indicating the degree of power consumption reduction; and An IE for controlling the radio signal communicated between the slave station device 20 and the UE. The radio signal defined here includes at least one of a downlink signal transmitted from the slave station device 20 to the UE and an uplink signal transmitted from the UE to the slave station device 20. The control unit 12 may also change the degree of power consumption reduction of the slave station device 20 indicated by the first power saving control information based on, for example, the communication status between the slave station device 20 and the UE. The communication unit 11 may transmit the first power saving control information directly to the slave station device 20 that is the target of the power saving control, or may transmit the information to a relay device that relays between the slave station device 20 and the master station device 10. Specific examples of these IEs will be described in embodiment 3.

[0030] The slave station device 20 serves at least one cell. The base station B1 operates the cell to connect to and wirelessly communicate with UEs located in the cell. Note that the manner in which the cell is operated changes depending on the actions performed by the base station B1.

[0031] The slave station device 20 reduces its power consumption based on the first power saving control information from the master station device 10. Alternatively, the slave station device 20 may reduce its power consumption based on control information transmitted by the relay device based on the first power saving control information. The target for which the slave station device 20 reduces power consumption may be at least one of a wireless communication unit that performs wireless communication in the UE, a control unit that controls the wireless communication unit, etc. The control unit of the slave station device 20 is configured to be able to perform at least processes other than the processes performed by the master station device 10, among the processes of multiple layers that can be performed by the base station.

[0032] However, even when the slave station device 20 receives the first power saving control information from the master station device 10 or the control information transmitted by the relay device, the slave station device 20 may refrain from executing the control to reduce its power consumption based on the state of the slave station device 20 (e.g., the state of communication with the UE or the power saving state of the slave station device 20).

[0033] If the base station B1 is a base station in a fifth-generation mobile communication system, its configuration may be a C-RAN (Cloud RAN) configuration. In this case, the base station B1 has three nodes: a Radio Unit (RU), a Distributed Unit (DU), and a Central Unit (CU). The RU, DU, and CU are connected in this order.

[0034] The slave station device 20 includes at least an RU to realize signal communication between the UE and the DU. Specifically, when transmitting a radio signal to the UE, the RU converts a digital signal output from the DU into an analog signal and transmits the signal to the UE via an antenna. On the other hand, when receiving a radio signal from the UE, the RU converts an analog signal received from the UE via the antenna into a digital signal and outputs the signal to the DU.

[0035] Furthermore, the CU executes any one or more processes among the processes of the multiple layers that the base station can execute. The DU can execute processes related to layers lower than those of the CU. Any method can be considered for functionally separating the processes of the multiple layers executed by the base station between the DU and the CU. For example, the CU may be configured as a node that hosts at least the PDCP layer, and the DU may be configured as a node that hosts the MAC layer.

[0036] When the base station B1 has nodes of RU, DU, and CU, the master station equipment 10 and slave station equipment 20 have the following nodes: (1) The master station equipment 10 has a CU and a DU, and the slave station equipment 20 has an RU. (2) The master station equipment 10 has a CU, and the slave station equipment 20 has a DU and an RU. (3) The master station equipment 10 has a CU, the slave station equipment 20 has an RU, and the relay equipment of the master station equipment 10 and the slave station equipment 20 has a DU. (4) The master station equipment 10 has a DU, the slave station equipment 20 has an RU, and the control equipment connected to the upper level of the master station equipment 10 has a CU.

[0037] In the above (1) and (2), the base station B1 can be configured with two devices: a master station device 10 and a slave station device 20. The configuration (1) is also referred to as a lower layer split, and the configuration (2) is also referred to as a higher layer split. As an example, in a lower layer split, the DU can perform processing of the lower layers of the physical layer, and the CU can perform processing of the upper layers of the physical layer, the MAC layer, the RLC layer, and the PDCP layer. As another example, in a higher layer split, the DU can perform processing of the physical layer, the MAC layer, and the RLC layer, and the CU can perform processing of the PDCP layer.

[0038] On the other hand, in the above (3) and (4), the base station B1 is made up of three devices: a master station device 10, a slave station device 20, and a relay device or a control device. This configuration is also called a cascade connection.

[0039] As another example, if the base station B1 is a base station in a fourth-generation mobile communication system, the base station B1 may be divided into two nodes: a baseband unit (BBU) and a remote radio head (RRH). In this case, the master station device 10 includes a BBU, and the slave station device 20 includes an RRH.

[0040] Furthermore, the BBU executes any one or more processes among the processes of the multiple layers that the base station can execute. The RRH can execute processes related to layers lower than the BBU. Any method can be considered for functionally separating the processes of the multiple layers executed by the base station between the BBU and the RRH. For example, the BBU may execute processes of at least the physical layer, MAC layer, RLC layer, and PDCP layer. In this case, the RRH executes processes related to RF (Radio Frequency).

[0041] 2 is a sequence diagram showing an example of the operation of the master station device 10. An example of the operation of the master station device 10 will be described below with reference to FIG. 2. The details of the process are as described above, and therefore will not be described again.

[0042] The control unit 12 causes the communication unit 11 to transmit first power-saving control information for reducing power consumption of the slave station device 20 (step S11). The slave station device 20 executes power-saving control based on the first power-saving control information, or suspends the execution of the control. The slave station device 20 can also transmit a response message to the master station device 10 in response to the received power-saving control information.

[0043] [Explanation of Effects] In the first embodiment, in a base station B1 made up of multiple devices, the master station device 10 transmits first power saving control information for reducing the power consumption of the slave station devices 20. The slave station devices 20 can reduce their power consumption accordingly, which contributes to suppressing the power consumption of the base station B1.

[0044] Embodiment 2 Hereinafter, embodiment 2 will be described with reference to the drawings. In this embodiment 2, a control device capable of reducing the power consumption of a wireless communication unit of a base station will be described. Note that the configuration and processing described below are examples and are not limited to these.

[0045] [Configuration Description] Fig. 3 is a block diagram showing an example of a control device. The control device 30 is connected to a base station 40. Although only one base station 40 is shown in Fig. 3, a plurality of base stations 40 may be connected to the control device 30.

[0046] The base station 40 has a wireless communication unit that communicates wirelessly with a UE (not shown). The base station 40 may be configured as a single device, or as shown in the first embodiment, may be configured as multiple devices (e.g., a master station device and a slave station device). As an example, the wireless communication unit is configured as an RU of the slave station device. An example of the base station 40 is the base station B1 in the first embodiment.

[0047] The control device 30 may be directly connected to the base station 40, or may be connected via one or more relay devices. A relay device is any device that relays communications. Furthermore, since the control device 30 is located higher than the base station 40 in the communication system, the control device 30 can also be expressed as a "higher-level device" and the base station 40 as a "lower-level device." The control device 30 is a device provided closer to the core network than the base station 40, and may be, for example, a RIC (RAN Intelligent Controller), but is not limited to this.

[0048] 3, the control device 30 includes a communication unit 31 and a control unit 32. The communication unit 31 and the control unit 32 may be software or modules that are executed by a processor executing a program stored in a memory. Alternatively, the communication unit 31 and the control unit 32 may be hardware such as a circuit or a chip.

[0049] The communication unit 31 connects to the base station 40 and the like and communicates to transmit and receive various information. The control unit 32 reads and executes various information and programs stored in memory to execute various processes of the control device 30. The control unit 32 can also perform processing in accordance with at least one or all of the setting information such as various IEs, various fields, and various conditions included in a message received by the communication unit 31. The communication unit 31 is, for example, a transceiver.

[0050] The control unit 32 causes the communication unit 31 to transmit second power-saving control information for reducing the power consumption of the wireless communication unit. The second power-saving control information may include, for example, an enable signal indicating only whether power-saving control is enabled or disabled, or may include detailed information indicating a detailed method for the base station 40 to save power. This second power-saving control information may be different from or the same as the first power-saving control information in the first embodiment. Examples of the detailed information are as described in the first embodiment. Furthermore, the communication unit 31 may transmit the second power-saving control information directly to the base station 40 that is the target of the power-saving control, or may transmit it to the base station 40 via a relay device that relays between the base station 40 and the control device 30. The control unit 32 is, for example, a processor.

[0051] Fig. 4 is a sequence diagram showing an example of the operation of the control device 30. Hereinafter, an example of the operation of the control device 30 will be described with reference to Fig. 4. Note that the details of the process are as described above, and therefore will not be described again.

[0052] The control unit 32 causes the communication unit 31 to transmit second power saving control information for reducing power consumption of the wireless communication unit of the base station 40 (step S21). The base station 40 executes power saving control based on the second power saving control information, or suspends the execution of the control. In response to the received second power saving control information, the base station 40 can transmit a response message to the control device 30.

[0053] [Explanation of Effect] In the second embodiment, the control device 30 transmits second power saving control information for reducing the power consumption of the wireless communication unit of the base station 40. The base station 40 can reduce its power consumption accordingly, which contributes to suppressing the power consumption of the base station 40.

[0054] Embodiment 3 Hereinafter, embodiment 3 will be described with reference to the drawings. In embodiment 3, a specific example of a system including base station B1 and control device 30 described in embodiments 1 and 2 will be disclosed. However, the specific example of the devices shown in embodiments 1 and 2 is not limited to the following.

[0055] [Configuration Description] Fig. 5 is a block diagram showing an example of a communication system. The communication system S1 is a communication system in a fifth-generation mobile communication system, and is provided with, from the upper communication side, a control device 100, a master station device (CU and DU) 200, a slave station device (RU) 300, and a UE 400. More specifically, communication is connected in the order of the control device 100, the CU 201 of the master station device 200, the DU 202 of the master station device 200, the RU 300, and the UE 400.

[0056] Here, the master station device 200 and the RU 300 (i.e., functional units or devices of the CU, DU, and RU) constitute a base station, and perform wireless communication with the UE 400 by providing a cell. In this example, the wireless communication is performed using the OFDM method, but the method used is not limited to this. The master station device 200 is an example of the base station B1 in the first embodiment. In FIG. 5, RUs 300A and 300B are provided as the RU 300, and the RUs 300A and 300B provide cells 1 and 2, respectively, thereby enabling communication with the UEs 400A and 400B. However, the number of slave station devices provided is not limited to that shown in FIG. 5.

[0057] In this example, the control device 100 and the CU 201 are connected via an O-RAN (Open Radio Access Network) E2 interface, the CU 201 and the DU 202 are connected via an F1 interface, and the RU 300 and the UE 400 are connected via a Uu interface. The Uu interface may be a different interface for each cell. Furthermore, the network between the DU 202 and the RU 300 forms a fronthaul, and in this example, they are connected by wire. However, the method for connecting each device is not limited to this. Each device will be described in detail below.

[0058] The control device 100 is an example of the control device 30 in the second embodiment and is a near real-time RIC in the third embodiment. However, the control device 100 may be another type of device, such as a non-near real-time RIC. The control device 100 acquires traffic information indicating the traffic volume of the RU 300, which is a measurement value, as the communication state of the cell provided by the base station. This traffic information is transmitted to the control device 100, for example, from a CU 201 connected to the RU 300 or a core network device (not shown). Based on the traffic information, the control device 100 transmits an energy saving enable signal EN1 (hereinafter, signal EN1) to the CU 201 of the master station device 200. The signal EN1 is an example of a second power saving control signal in the second embodiment. However, the control device 100 may transmit the signal EN1 to the DU 202 instead of or in addition to the CU 201. In this case, the energy saving operation of the DU 202 is directly controlled.

[0059] The signal EN1 is a signal that includes cell designation information that designates the cell (RU 300) to be controlled, and an IE that indicates whether the power saving state of each RU 300 in the base station is on or off. The control device 100 determines whether the traffic value indicated by the traffic information is, for example, below a predetermined threshold, and if the traffic value is below the predetermined threshold, it is possible to output the signal EN1 that includes an IE that indicates that the power saving state is on (Energy saving enable IE). However, the signal EN1 may also include an IE that indicates specific parameters of the power saving state of the RU 300 (Energy saving state IE). In this example, the signal EN1 includes the following IEs for each RU 300 to be controlled: Energy saving enable IE: {ON, OFF} Energy saving state IE: {S 25 ,S 50 ,S 75 ,S 100} When the Energy saving enable IE is ON, the power saving state of the RU 300 is ON, and when it is OFF, the power saving state of the RU 300 is OFF. The Energy saving state IE is an IE that indicates the degree of reduction in power consumption.

[0060] where S 25 is a parameter that indicates the degree of power consumption reduction when the traffic of RU300 is between 0 and 25%, and S 50 is a parameter that indicates the degree of reduction in power consumption when the traffic of the RU 300 is 25 to 50%. 75 is a parameter that indicates the degree of power consumption reduction when the traffic of RU300 is 50 to 75%, and S 100 is a parameter that indicates the degree of reduction in power consumption when the traffic of the RU 300 is between 75% and 100%. 25 ,S 50 ,S 75 In this case, there are unused resources in the traffic of RU300, so the Energy saving enable IE is ON. 100In this case, since the traffic in the RU 300 is high, the RU 300 needs to use its communication function to the maximum. Therefore, the Energy saving enable IE is set to OFF.

[0061] The control device 100 determines the relationship between the traffic values ​​and their fluctuations indicated by the traffic information and a predetermined threshold, and then, based on the determination result, if necessary, changes at least one of the energy saving enable IE and the energy saving status IE included in the signal EN1.

[0062] 6A is a graph showing an example of the transition of cell traffic and the energy saving status IE. FIG. 6A shows that, over time, traffic increases monotonically from less than 25%, exceeds 75%, and then decreases monotonically to a value less than 25% again. When traffic increases, the control device 100 changes the energy saving status IE as follows: When traffic increases to 25%: S 25 From S 50 If traffic increases by 50%, 50 From S 75 If traffic increases to 75%, 75 From S 100 On the other hand, when the traffic decreases, the control device 100 changes the energy saving state IE as follows: When the traffic decreases to (75-Hy1): S 100 From S 75 ・When traffic decreases to (50-Hy2)%: S 75 From S 50 ・When traffic decreases to (25-Hy3)%: S 50 From S 256A, 25%, 50%, and 75% are set as traffic thresholds for changing the setting of the energy saving state IE. Also, to prevent the energy saving state IE from switching too frequently, hysteresis values ​​Hy1 to Hy3 are set for each threshold used to determine when traffic is decreasing.

[0063] Here, the threshold at which the Energy saving enable IE switches from ON to OFF when traffic increases is 75%, and the threshold at which the Energy saving enable IE switches from OFF to ON when traffic decreases is (75-Hy1)%. The control device 100 determines whether to turn Energy saving enable ON or OFF by comparing the traffic measurement value with the threshold for the Energy saving enable IE. Then, when Energy saving enable is ON, the control device 100 compares the traffic measurement value with the threshold for the above-mentioned Energy saving status IE to determine the Energy saving status IE.

[0064] Note that the information on the communication status of a cell used to set the energy saving status IE is not limited to traffic information. As the communication status of a cell, the control device 100 may acquire measured values ​​such as the radio resource usage rate and the UE scheduling queue length (average waiting time), and use this information to determine the energy saving status to be set for the RU 300. These measured values ​​also indicate the communication status of the RU 300, and may be measured by, for example, a DU 202 connected to the RU 300 and transmitted to the control device 100. The DU 202 may transmit the communication status information directly to the control device 100, or may transmit it to the control device 100 via the CU 201. By acquiring the communication status information in this manner, the control device 100 can monitor the communication status of each cell and perform determination and IE change processing.

[0065] FIG. 6B is a graph showing an example of the transition of the cell's radio resource usage rate and the energy saving status IE. Here, the radio resource usage rate refers to the usage rate of all radio resources (i.e., radio resources that are originally available) of the RU 300. Even when such radio resource usage rate information is used as the communication state of the cell provided by the base station, rather than traffic information, the control device 100 can determine the energy saving status IE as described above. However, the definition of the radio resource usage rate is not limited to the above example. For example, a radio resource usage rate of 100% may be defined as the use of all radio resources of the RU 300, rather than the use of all radio resources available at the time of measurement. Here, if radio resources are limited by the energy saving setting set by the control device 100, the term "all radio resources available at the time of measurement" refers to the radio resources in that limited state.

[0066] The communication status information may be reported by being transmitted to the control device 100 periodically (for example, every minute or several minutes), or may be reported by being transmitted aperiodically to the control device 100. As an example of aperiodically transmitting communication status information, when the CU 201 or DU 202 detects the occurrence of an event related to a certain measurement value of the communication status of the RU 300, the CU 201 or DU 202 reports the communication status information by transmitting it to the control device 100 (event-driven reporting). An example of an event is whether the measurement value exceeds or falls below a predetermined threshold, but this is not limited to this.

[0067] Furthermore, the control device 100 can also control the RU 300 not to transmit or receive radio signals. This control can be achieved, for example, by defining S0 in the above-mentioned energy saving state IE, which does not allow transmission or reception of radio signals. The control device 100 determines the energy saving state of the RU 300 in the above manner.

[0068] Returning to Fig. 5, the explanation will be continued. When the CU 201 receives the signal EN1, it outputs an energy saving enable signal EN2 (hereinafter, signal EN2) based on the signal EN1 to the DU 202. However, as described above, when the control device 100 transmits the signal EN1 to the DU 202, the CU 201 does not necessarily need to output the signal EN2 to the DU 202. The signal EN2 is an example of a first power saving control signal in the first embodiment.

[0069] The CU 201 may transfer the contents of the signal EN1 directly to the DU 202 as the signal EN2, or may add detailed information related to power saving control to the contents of the signal EN1 for each RU 300 to be controlled and output the resulting signal to the DU 202 as the signal EN2. For example, the control device 100 determines only the energy saving enable IE described above for the cell to be controlled, and transmits the signal EN1 including the IE and cell designation information to the CU 201. When the CU 201 receives the signal EN1, it determines whether the energy saving enable IE is ON. If the IE is ON, the CU 201 determines the energy saving status IE based on communication status information of the cell to be controlled that was previously acquired. The method for determining the energy saving status IE is as described above, and therefore will not be described here. The CU 201 then adds the energy saving status IE to the contents of the signal EN1 and transmits the result to the DU 202 as the signal EN2.

[0070] In this example, when information on the communication state of the cell of the RU 300 is transmitted to the control device 100, the CU 201 can acquire the information on the communication state. However, in this example, the CU 201 may acquire information on the communication state of the cell (for example, information on measurement values), and the control device 100 may not acquire the information.

[0071] In this case, the CU201 monitors the communication status, and the CU201 compares the measurement value of the communication status with the threshold value of the Energy saving enable IE to determine whether to turn Energy saving enable ON or OFF. If Energy saving enable is ON, the CU201 compares the measurement value of the communication status with the threshold value related to the Energy saving status IE described above to determine the Energy saving status IE. Then, the CU201 transmits information indicating that Energy saving enable is ON to the control device 100. In this example, the control device 100 determines whether energy saving can be implemented for the target cell, and if implementation is possible, transmits a permission notification to the CU201 to turn Energy saving enable ON.

[0072] Thereafter, the CU 201 outputs a signal EN2 including designation information of the target cell, an energy saving enable IE, and an energy saving status IE to the DU 202. Here, the details of the comparison process between the measurement value of the communication status and the predetermined threshold executed in the CU 201 are the same as those shown in the control device 100, and therefore will not be described again.

[0073] In accordance with the signal EN2 output from the CU 201 or the signal EN1 output from the control device 100, the DU 202 performs power saving control on the RU 300 identified by the cell specification information. In particular, the DU 202 performs at least one of the following operations based on the energy saving state IE included in the signal EN2 or the signal EN1: configuring the DU 202 itself for power saving control, or generating an energy saving control signal CI (hereinafter simply referred to as signal CI) for causing the RU 300 to perform a power saving operation. The signal CI is an example of a first power saving control signal in the first embodiment. The signals EN1 and EN2 output from the upper level of the DU 202 are signals for high-level control, and may include, for example, only an energy saving enable IE as control information. In contrast, the signal CI includes not only the energy saving enable IE but also detailed control information for the RU 300 as control information. However, at least one of the signals EN1 and EN2 may further include control information for detailed control information for the RU 300.

[0074] The signal CI includes the following IEs in addition to the cell specification information: Energy saving enable IE: {ON, OFF} Energy saving control IE The energy saving control IE is an IE that controls the radio signal communicated between the RU 300 and the UE 400. In detail, this IE specifies details of power saving control of at least one of the time domain or maximum modulation index in the radio communication of the RU 300, or the frequency related to the radio signal. This will be described in detail later.

[0075] When generating a signal CI, the DU 202 transmits the signal CI to each RU 300 that is subject to power saving control. In Fig. 5, a signal CI1 is transmitted to the RU 300A, and a signal CI2 is transmitted to the RU 300B.

[0076] The RU 300 changes its operation mode based on the energy saving control information notified from the DU 202. For example, if the notified energy saving enable IE is ON, the RU 300 operates in the power saving mode based on the details of the power saving control specified by the energy saving control IE. Note that if the notified energy saving enable IE is ON, the RU 300 operates in the power saving mode regardless of whether the most recently notified energy saving enable IE is ON or OFF. Furthermore, if the notified energy saving enable IE is OFF, the RU 300 does not operate in the power saving mode.

[0077] 7 is a sequence diagram showing an example of the operation of the communication system S1, and the operation of the entire communication system S1 will be described with reference to this diagram. Note that the details of each process executed by each device in the communication system S1 are as described above.

[0078] First, the control device 100 performs the above-described determination based on the acquired communication status information of each RU 300, and changes the power saving control for each RU 300 (step S31). The change in power saving control includes at least one of changing the energy saving enable IE from ON or OFF to the other, or changing the energy saving status IE to a different parameter. The control device 100 transmits a signal En1 related to the changed power saving control to the CU 201 (step S32).

[0079] When CU201 receives signal En1, it transmits signal En2 based on signal En1 to DU202 (step S33). When DU202 receives signal En2, it generates signal CI based on signal EN2 to cause RU300 to perform power saving operation. DU202 transmits signal CI1 to RU300A (step S34) and signal CI2 to RU300B (step S35). When RU300A receives signal CI1, it changes its operating mode based on signal CI1 (step S36). When RU300B receives signal CI2, it changes its operating mode based on signal CI2 (step S37).

[0080] Next, we will explain examples of energy saving control IEs generated by the DU 202. However, instead of the DU 202, the CU 201 or the control device 100 may generate the energy saving control IEs shown below and transmit them to the RU 300. Furthermore, the examples shown in (A) to (C) can be used in appropriate combinations.

[0081] (A) When the Energy Saving Control IE Specifies Details of the Time Domain in Wireless Communication: The DU 202 can generate, as an Energy Saving Control IE, ON / OFF information for each resource on the time axis in the wireless signal handled by the RU 300, so as to correspond to the Energy Saving Status IE included in the signal EN2 transmitted by the CU 201 or the signal EN1 transmitted by the control device 100. Note that, among wireless signals, targeting Downlink signals for power saving control has a greater effect in reducing power consumption than targeting Uplink signals for power saving control. Therefore, in this example, the wireless signals subject to power saving control include at least Downlink signals. The DU 202 includes the generated Energy Saving Control IE in a signal CI and transmits it to the RU 300.

[0082] The DU 202 specifies whether each of the 14 OFDM symbols (hereinafter simply referred to as symbols) in one time slot of a radio signal transmitted or received by the RU 300 to be controlled is to be on or off (used or unused). As an example, the 14 symbols can be represented by a 14-bit bitmap, with each symbol corresponding to one bit. In this case, the DU 202 assigns a bit value of 1 or 0 to each of bits 0 to 13 (i.e., symbols 0 to 13), thereby specifying whether each symbol is on or off. A bit value of 1 for a symbol means that the symbol is used (i.e., on), and a bit value of 0 means that the symbol is not used (i.e., off). The DU 202 transmits the bitmap, in which the bit values ​​for symbols 0 to 13 are defined, to the RU 300 as an energy saving control IE.

[0083] When setting the ON / OFF of each symbol for both the downlink signal transmitted by the RU 300 and the uplink signal received by the RU 300, the DU 202 may determine the ON / OFF of each symbol independently for each signal, or may determine the ON / OFF for both signals in common. Furthermore, the DU 202 may determine the ON / OFF of each symbol in the downlink signal (or the downlink signal and the uplink signal) based on the capability information of the RU 300. Details of this capability information will be described later.

[0084] FIG. 8A shows the energy saving state IE in S. 100 If S 100 An example of a bitmap corresponding to this is shown below. In this bitmap, all symbols are on (all bit values ​​are 1). When the RU 300 receives an energy saving control IE indicating this bitmap, it turns on the power of the circuits or components used for transmission or reception for all symbols. Therefore, power saving operation is not performed, and wireless signals are transmitted or received in the usual manner. In this case, the power consumption reduction effect is 0%.

[0085] FIG. 8B shows the energy saving state IE in S. 50 If S 50 An example of a bitmap corresponding to this is shown below. In this bitmap, the RU 300 turns on the first seven symbols (bits 0 to 6) of one time slot and turns off the last seven symbols (bits 7 to 13). This setting allows the RU 300 to communicate 50% of the traffic. When the RU 300 receives an energy saving control IE indicating this bitmap, it turns on the power of the circuits or components used for transmission or reception in the first seven symbols, but turns off the power of those circuits or components in the last seven symbols. This enables power saving operation, resulting in a reduction in power consumption of up to 50%.

[0086] S 50 The bitmap corresponding to this is not limited to that shown in Figure 8B. For example, it may be a bitmap in which the first 7 symbols (bits 0 to 6) in one time slot are OFF and the second 7 symbols (bits 7 to 13) are ON. Also, if the Energy saving status IE is S, 50 If not only S 25 and S 75 In the same manner as described above, the DU 202 can set the bitmap so that it can execute communication of 25% or 75% of the traffic. 25 , S 50 or S 75 When at least one of the above is true, it is preferable to set two or more consecutive symbols to be turned off in the bitmap. Also, it is preferable to set a larger number of consecutive symbols to be turned off in the bitmap, as this increases the power saving effect.

[0087] Note that if S0 is set in the Energy Saving State IE, all symbols are turned off in the bitmap. If the Energy Saving State IE: S0 is set for the downlink signal, the RU 300 will stop transmitting. When the RU 300 receives an Energy Saving Control IE indicating this bitmap, it turns off the power to the circuits or components used for transmission or reception for all symbols. However, the RU 300 may leave the power on for its control system and circuits or components related to the standby function. The power saving operation performed in this case can reduce power consumption by up to 100%.

[0088] In addition, DU202 is in the Energy saving state IE is S 100 If the parameter is other than , the RU 300 can determine which circuits or components of its own device it can selectively power off based on the RU 300's capability information (described later). Then, based on this determination, the RU 300 transmits the signal CI containing information on the circuits or components to be powered off to the RU 300. The RU 300 can power off the circuits or components specified by the information on the circuits or components to be powered off when the symbol defined in the energy saving control IE turns off. In other words, the DU 202 can support the power-off control of the RU 300.

[0089] The energy saving control IE described above can be applied to any existing radio resource protocol such as RRC, DCI (Downlink Control Information) format, etc. Therefore, it can be applied to any existing wireless communication for UE.

[0090] Figure 9 shows an example of implementing the energy saving control IE. In Figure 9, up to 16 types of PDSCH-Time Domain Resource Allocation (TDRA) can be configured for one UE. For example, when the energy saving state IE is S, 100(All symbols are available) and the Energy saving status IE is S 50 In this case, the DU 202 can set the parameters for the UE 400 by RRC as follows: For any one or more TDRAs, S 100 For other TDRAs, set the startSymbolAndLength parameter such that S + L ≤ 14. 50 As a parameter for this, set the startSymbolAndLength parameter such that S + L ≦ 7.

[0091] In addition, DU202 can also notify UE400 of the index of a PDSCH-TDRA having parameters that can be used within the symbol range notified by the energy saving control IE, out of a maximum of 16 types of PDSCH-TDRAs set, by using the "Time domain resource assignment" of the DCI.

[0092] (B) When the energy saving control IE specifies details of the maximum modulation depth in the radio signal: The DU 202 may specify, as the energy saving control IE, the maximum modulation depth in the radio signal of the RU 300. The maximum modulation depth is indicated by a set of, for example, {BPSK (Binary Phase Shift Keying), QPSK (Quadrature Phase Shift Keying), 16QAM (Quadrature Amplitude Modulation), 64QAM, 256QAM, 1024QAM, ...}.

[0093] The RU 300 can set the operating point (bias current) of the power transistor in the power amplifier section within the RU 300 to an optimal value based on the maximum modulation index notified by the DU 202 via the energy saving control IE. Generally, the higher the maximum modulation index, the higher the peak of the wireless signal. Therefore, the bias current value must be increased to amplify the wireless signal without distortion, which increases the power consumption of the RU 300. However, by lowering the maximum modulation index, it is possible to reduce the power consumption of the RU 300. In this case, the DU 202 allocates resources to the RU 300 so as not to exceed the maximum modulation index notified to the RU 300 via the energy saving control IE.

[0094] (C) When the energy saving control IE specifies details of the frequency related to the radio signal, the DU 202 may specify the frequency related to the radio signal as the energy saving control IE. Here, the frequency related to the radio signal indicates at least one of the center frequency or maximum bandwidth of the radio communication signal, or the operating frequency of a circuit used for communication in the RU 300. The circuit used for communication may be, but is not limited to, an inverse fast fourier transform (iFFT) size or a digital-to-analog (DA) converter.

[0095] [Explanation of Effect] Based on recent social circumstances, there is a demand for reducing power consumption in mobile networks. In mobile networks, power is consumed mainly in the RAN, and it is said that most of the power consumption of the RAN is consumed in the radio section of the RAN. Therefore, in order to reduce the power consumption of a mobile network, it is necessary to reduce the power consumption of the radio section. Meanwhile, it is expected that the adoption of devices with open interfaces as radio sections of mobile networks will increase in the future. The communication system S1 described in embodiment 2 can solve this problem.

[0096] For example, the master station device 200 transmits a signal CI (first power saving control information) to reduce the power consumption of the slave station device (RU) 300 that wirelessly communicates with the UE 400. The slave station device (RU) 300 can reduce its power consumption accordingly, thereby reducing the power consumption of the mobile network.

[0097] In particular, when multiple slave station units (RUs) 300 are provided, the master station device 200 can simultaneously control the power consumption of multiple (e.g., all) slave station units (RUs) 300. In a method in which the slave station unit (RU) 300 reduces its own power consumption, for example, if some of the wireless bands of the multiple slave station units (RUs) 300 are in use, the slave station unit (RU) 300 cannot perform power-saving control on the unused bands. This limits the power-saving effect. However, the method disclosed herein allows the master station device 200 to identify unused wireless resources and control the power consumption of the multiple slave station units (RUs) 300, thereby further improving the power-saving effect.

[0098] Furthermore, the master station equipment 200 may change the degree of reduction in power consumption of the slave station equipment (RU) 300 indicated by the signal CI, based on the communication status between the slave station equipment (RU) 300 and the UE 400. This allows the slave station equipment (RU) 300 to operate adaptively with low power consumption according to an index of the communication status that changes over time, thereby enabling power-saving operation according to the situation.

[0099] Here, the information indicating the communication state may be information indicating the usage rate of radio resources in communication between the UE 400 and the slave station unit (RU) 300. Alternatively, the information indicating the communication state may be information indicating the traffic volume in communication between the UE 400 and the slave station unit (RU) 300. This allows the master station unit 200 to control power saving using an index suitable for wireless communication.

[0100] The signal CI may also include information for controlling the radio signal communicated between the slave station unit (RU) 300 and the UE 400. This makes it possible to reduce the power consumption of the radio signal section that mainly consumes power in the slave station unit (RU) 300, thereby increasing the power saving effect.

[0101] Here, the signal CI can control at least one of turning on or off symbols in a time slot of the radio signal, the maximum modulation depth of the radio signal, or the frequency of the radio signal. In other words, the maximum throughput of the cell provided by the slave station unit (RU) 300 can be adjusted in at least one of the time domain, frequency domain, and spatial domain. Therefore, for example, when the cell traffic is low to medium, it is possible to adaptively turn off radio resources that are not required for use. Therefore, the master station unit 200 can secure radio resources for communication while reducing power consumption in the network.

[0102] For example, when the CI signal is used to set the on or off state of a symbol in a time slot of a wireless signal, the slave station unit (RU) 300 can continuously place the transmission amplifier circuit in a power-saving state during the period of consecutive off symbols. Since the slave station unit (RU) 300 knows in advance the period during which it can be placed in a power-saving state, it can also place circuits that take more than one symbol to transition from an on state to an off state and then back on into a power-saving state. Therefore, a wide variety of circuits can be targeted for power-saving control, which is expected to significantly reduce the power consumption of the slave station unit (RU) 300. Furthermore, existing dynamic power-saving control techniques can be used for symbols that are notified to be placed in an on state.

[0103] Furthermore, when the maximum modulation index of the radio signal is set for the signal CI, the peakiness of the transmission signal is alleviated by reducing the maximum modulation index of the transmission signal in the slave station unit (RU) 300. This makes it possible to alleviate the operating point (e.g., transistor bias current) of the power amplifier in the slave station unit (RU) 300 or in the repeater connecting the slave station unit (RU) 300 and the UE 400, thereby reducing power consumption.

[0104] The master station device 200 may also receive an energy saving enable IE (enable signal) for reducing the power consumption of the slave station device (RU) 300 from the external control device 100, and generate and transmit a signal CI based on the energy saving enable IE. The control device 100 can control the power saving operation of the slave station device (RU) 300 via the master station device 200.

[0105] From another perspective, the control device 100 can transmit a signal EN1 (second power saving control information) to a base station having a slave station unit (RU) 300 that wirelessly communicates with the UE 400, for reducing the power consumption of the slave station unit (RU) 300. The base station can reduce the power consumption accordingly.

[0106] The control device 100 may also change the degree of reduction in power consumption of the slave station equipment (RU) 300, which is indicated by the energy saving state IE of the signal EN1, based on the communication state between the slave station equipment (RU) 300 and the UE 400. This makes it possible to adaptively operate the slave station equipment (RU) 300 with low power consumption according to an index of the communication state that changes over time, thereby enabling power-saving operation according to the situation.

[0107] Here, the information indicating the communication state may be information indicating the usage rate of wireless resources in communication between the UE 400 and the slave station unit (RU) 300. This allows the control device 100 to control power saving using an index suitable for wireless communication.

[0108] The signal EN1 may also include information for controlling the radio signals communicated between the slave station unit (RU) 300 and the UE 400. This makes it possible to reduce the power consumption of the radio signal section, which is the main consumer of power in the slave station unit (RU) 300, thereby increasing the power saving effect.

[0109] Here, the signal EN1 can control at least one of turning on or off a symbol in a time slot of the radio signal, the maximum modulation depth of the radio signal, or the frequency of the radio signal. Therefore, the control device 100 can secure radio resources used for communication while reducing power consumption of the network.

[0110] The control device 100 may also transmit a signal EN1 to the master station device 200 to reduce the power consumption of the slave station device (RU) 300 having a wireless communication unit. The control device 100 can control the power saving operation of the wireless communication unit of the base station even when the base station is configured to be divided into multiple devices.

[0111] Here, the signal EN1 may include an enable signal for reducing the power consumption of the slave station unit (RU) 300. This allows the control device 100, which is the higher-level device, to directly instruct the slave station unit (RU) 300 whether or not to reduce its power consumption, thereby making it easier to manage the base station.

[0112] Fourth Embodiment A variation of the third embodiment will be further described below. Note that, in the following, explanations of the same points as those of the third embodiment will be omitted.

[0113] The control device 100 may inquire of the RU 300 about what kind of function (energy saving capability) the RU 300 has as a function that can reduce power consumption. The inquiry is transmitted to the RU 300 via the CU 201 and the DU 202.

[0114] When the RU 300 receives an inquiry, it transmits a report indicating the energy saving capability of the RU 300 to its higher-level devices, the parent station device 200 and the control device 100. This energy saving capability information is stored in, for example, a storage unit of the RU 300, and the RU 300 generates this report by referring to the storage unit. Details of the energy saving capability information will be described later.

[0115] When the DU 202 receives the report, it transfers the report to the CU 201. At this time, the DU 202 may transfer the received report as is. Alternatively, the DU 202 may add information about the energy saving capability of the DU 202 to the report and transfer the report by referring to information about the energy saving capability of the DU 202 stored in the storage unit of the DU 202.

[0116] The DU 202 may also compare the energy saving capability indicated in the received report with its own energy saving capability, and determine whether any of the energy saving capabilities in the report are not supported by the DU 202. If any of the energy saving capabilities in the report are not supported by the DU 202, the DU 202 excludes those functions from the energy saving capability described in the report. In this way, the DU 202 creates a report that includes, as energy saving capabilities, functions that are commonly supported by the DU 202 and the RU 300, and transfers the report to the CU 201.

[0117] When the CU 201 receives a report from the DU 202, it transfers the report to the control device 100. At this time, the CU 201 may transfer the received report as is. Alternatively, the CU 201 may add information about the energy saving capability of the CU 201 to the report and transfer the report by referring to information about the energy saving capability of the CU 201 stored in the storage unit of the CU 201. In this case, the report sent to the control device 100 includes information about the energy saving capability supported by the CU 201, the DU 202, and the RU 300.

[0118] The CU 201 may also compare the energy saving capabilities indicated in the received report with its own energy saving capabilities to determine whether any of the energy saving capabilities in the report are supported by the CU 201. If any of the functions not supported by the CU 201 are present, the CU 201 excludes those functions from the energy saving capabilities described in the report. If the report includes a function supported by both the DU 202 and the RU 300 as an energy saving capability, the CU 201 performs this exclusion process, so that the energy saving capability included in the report becomes a function supported by both the CU 201, the DU 202, and the RU 300. The CU 201 transmits the report after the above process to the control device 100.

[0119] When the control device 100 receives the report, it can present the energy saving capabilities included in the report to the user using a display unit or the like of the control device 100. As described above, the energy saving capabilities included in the report may be energy saving capabilities in the RU 300, or may be energy saving capabilities common to at least one of the CU 201 or the DU 202 and the RU 300. The user selects one or more energy saving capabilities from the presented functions and specifies them via an input unit of the control device 100. The control device 100 can identify the energy saving capabilities selected by the user as targets for power saving control in the RU 300.

[0120] However, the control device 100 may hide the energy saving capability included in the received report from the user without presenting it to the user. In this case, the control device 100 can automatically identify one or more arbitrary functions included in the energy saving capability included in the report as targets for power saving control in the RU 300.

[0121] 10 is a sequence diagram showing an example of the operation of the communication system S1, and the operation of the entire communication system S1 will be described with reference to this diagram. The details of each process executed by each device in the communication system S1 are as described above.

[0122] First, the control device 100 transmits an inquiry In to the RU 300A regarding the energy saving capability of the RU 300A (step S41). The CU 201 transfers the inquiry In from the control device 100 to the DU 202 (step S42), and the DU 202 transfers the inquiry In from the CU 201 to the RU 300A (step S43).

[0123] Based on the inquiry In, the RU 300A refers to the energy saving capability of its own device (step S44), creates a report Re including the energy saving capability, and transmits it to the control device 100 (step S45). The DU 202 transfers the report Re from the RU 300A to the CU 201 (step S46), and the CU 201 transfers the report Re from the DU 202 to the control device 100 (step S47). Note that the DU 202 or the CU 201 may process the report Re before transferring it to the higher-level device, as described above.

[0124] Note that at least one of the CU 201 and the DU 202 may report its own energy saving capability to the control device 100 separately (i.e., autonomously) from the report from the RU 300, rather than including it in the report from the RU 300 and reporting it to the control device 100. The control device 100 can individually acquire the energy saving capabilities of the CU 201, the DU 202, and the RU 300, and then determine, based on that information, functions to be subject to power saving control in the RU 300. For example, the control device 100 may identify energy saving capabilities commonly supported by the CU 201, the DU 202, and the RU 300, based on the acquired information, and identify the identified energy saving capability as a target for power saving control in the RU 300.

[0125] The CU 201 may also hide the energy saving capability of the RU 300 from the control device 100 without presenting it. For example, in the example of FIG. 10 , the CU 201, rather than the control device 100, may generate an inquiry In and transmit it to the RU 300A via the DU 202. As described above, the RU 300A creates a report Re including the energy saving capability of its own device and transmits it to the CU 201. When the DU 202 receives this report Re, it may forward the received report as is, or may add information about the energy saving capability of the DU 202 to the report and forward it. Furthermore, if the DU 202 finds a function that it does not support among the energy saving capabilities indicated in the received report, it may exclude that function from the report and forward the excluded report to the CU 201. By not transmitting the received report to the control device 100, the CU 201 can hide the energy saving capability of the RU 300A from the control device 100. Furthermore, the CU 201 can identify the target of power saving control in the RU 300A based on the acquired information on the energy saving capability.

[0126] Similarly, the DU 202 may hide the energy saving capability of the RU 300 from the CU 201 and the control device 100, rather than presenting it. For example, in the example of FIG. 10 , the DU 202, rather than the control device 100, may generate the inquiry In and send it to the RU 300A. As described above, the RU 300A creates a report Re including the energy saving capability of its own device and sends it to the DU 202. The DU 202 can hide the energy saving capability of the RU 300A from the higher-level device by not sending the received report to that higher-level device. Furthermore, the CU 201 can identify the target of power saving control in the RU 300A based on the acquired energy saving capability information.

[0127] A specific example of the energy saving capability that the RU 300 reports to a higher-level device such as the control device 100 will be described below.

[0128] (a) Energy saving capability in the time domain in wireless communication The RU 300 can report, in a report, information indicating whether ON / OFF switching is possible for each resource on the time axis in the wireless signal handled by the RU 300, as energy saving capability. In particular, the RU 300 can report information indicating whether ON / OFF switching is supported for each of the 14 symbols in one time slot in the wireless signal to be transmitted or received. Note that the wireless signal to be reported may include at least one of a downlink signal or an uplink signal, or may include at least a downlink signal.

[0129] Furthermore, instead of or in addition to reporting the above information, the RU 300 may report the on / off pattern of each symbol in one time slot that it supports (i.e., is able to implement) as energy saving capability. The energy saving capability is included in the report using, for example, the bitmap format shown in the third embodiment. The pattern that the RU 300 supports and can report may be any pattern, and for example, the S 100 , S 50 These include, but are not limited to:

[0130] When the RU 300 transmits pattern information for each symbol as the energy saving capability, the RU 300 may include the power consumption reduction effect for each pattern in the report as accompanying information. 100The power consumption reduction effect may be the amount of power consumption reduction when the RU 300 operates in the target pattern compared to when the RU 300 operates in the target state (state (a)). Alternatively, the power consumption reduction effect may be the amount of power consumption when the RU 300 operates in the target pattern. Such a numerical value can be expressed, for example, as a percentage, with the power consumption when the RU 300 operates in the normal state being 100%.

[0131] For example, RU300 is S 100 For the bitmap "11111111111111", the RU 300 may include "0%" as accompanying information in the report. 50 For at least one of the bitmaps "11111110000000" and "00000001111111", the report may include "40%" as accompanying information.

[0132] (b) Energy saving capability of maximum modulation depth of radio signals The RU 300 may report, as an energy saving capability, information on the maximum modulation depth that can be set, separate from the device's maximum modulation depth for the radio signals handled by the RU 300. The definition shown in the third embodiment can be applied to the maximum modulation depth. For example, the RU 300 is capable of supporting up to 256QAM. However, the RU 300 can report in the report that it is capable of operating with a maximum modulation depth less than 256QAM, such as 64QAM or 16QAM.

[0133] The RU 300 may report information about its power amplifier unit as energy saving capability in a report. The RU 300 may be, for example, an active array antenna. In this case, the following information, for example, is expected to differ depending on the vendor providing the RU 300: The arrangement of antenna elements in the active array antenna (e.g., N elements vertically and M elements horizontally); The amount of power supplied to each power amplifier; The type of antenna connected to each power amplifier (e.g., whether the connected antenna is an X-POL (Cross Polarized) antenna); and Support for operations using part of the array antenna. Therefore, the RU 300 can report at least any of this information as information about its power amplifier unit in a report. The operation using part of the array antenna is called "energy saving in the spatial domain" and can be included in the power saving control information for the corresponding RU 300.

[0134] Furthermore, when the RU 300 transmits information indicating the upper limit of the maximum modulation index as the energy saving capability, the RU 300 may include the power consumption reduction effect for each supported maximum modulation index as accompanying information in the report. The power consumption reduction effect may be, for example, the amount of power consumption reduced when the RU 300 operates at the target maximum modulation index compared to when the RU 300 operates in a state where the maximum modulation index is the upper limit. Alternatively, the power consumption reduction effect may be the amount of power consumed when the RU 300 operates at the target maximum modulation index. Such a numerical value may be expressed, for example, as a percentage, with the power consumption when the RU 300 operates in a state where the maximum modulation index is the upper limit being 100%.

[0135] (c) Energy saving capability in the frequency domain of radio signals The RU 300 may report the value (e.g., 2000 MHz to 2100 MHz, 2000 MHz to 2050 MHz, etc.) or its range (100 MHz, 50 MHz, etc.) supported as the frequency for the radio signals handled by the RU 300 as the energy saving capability. The definition of the frequency for the radio signals is as described in the third embodiment. The RU 300 reduces power consumption by operating with optimal circuit settings according to the specified control information. The base station configured by the RU 300 sets at least one of these frequency values ​​or ranges in the range in which the RU 300 can operate and transmits radio signals.

[0136] When the RU 300 transmits information about the frequency values ​​or frequency ranges supported by the RU 300 as energy saving capabilities, the RU 300 may include the power consumption reduction effect for the supported frequency values ​​or frequency ranges in the report as accompanying information. The power consumption reduction effect may be, for example, the amount of power consumption reduced when the RU 300 operates at a target frequency value compared to when the RU 300 operates at a frequency value at which power consumption is maximized. Alternatively, the power consumption reduction effect may be the amount of power consumed when the RU 300 operates at a target frequency value. Such a numerical value may be expressed, for example, as a percentage, with the power consumption when the RU 300 operates at the maximum power consumption state being set to 100%.

[0137] (d) Energy saving capability indicating unsupported function The RU 300 may or may not explicitly report a function that it does not support as an energy saving capability.

[0138] The RU 300 can report to the control device 100 a report that includes at least one of (a) to (d) as an energy saving capability. This allows the control device 100 to identify the target of power saving control in the RU 300 by grasping the energy saving capability of the RU 300. Furthermore, if the energy saving capability of at least one of the CU 201 and the DU 202 is included in the report, the control device 100 can identify the target of power saving control of at least one of the CU 201 and the DU 202 based on the report.

[0139] The control device 100 can also present the reported energy saving capability to the user. If the accompanying information shown in (a) to (c) is included in the report, the control device 100 can also present the accompanying information to the user. Based on the presented information, the user can specify the target of power saving control in the RU 300.

[0140] The control device 100 recognizes the target of power saving control in the RU 300 based on the energy saving capability included in the report previously received from the RU 300. Then, when determining the power saving state (energy saving state IE) of the RU 300 based on the communication state of the cell, the control device 100 can identify the energy saving capability that the RU 300 uses to reduce power consumption from among the energy saving capabilities that are the target of power saving control in the RU 300. For example, the control device 100 may compare the determined power saving state of the RU 300 with associated information on the energy saving capability that is the target of power saving control. This allows the control device 100 to identify the energy saving capability that is expected to have a power consumption reduction effect corresponding to the determined power saving state of the RU 300. Then, information on the identified energy saving capability (specific information) can be included in the signal EN1 and transmitted as an energy saving control IE. This specific information may also include information indicating setting values ​​for the functions of the RU 300.

[0141] Note that even if the control device 100 acquires information about the energy saving capability of the CU 201 in advance, it can recognize the target of power saving control in the CU 201 based on that information. Then, from among the energy saving capabilities that are the target of power saving control in the CU 201, it identifies the energy saving capability that the CU 201 uses to reduce power consumption. For example, the control device 100 identifies the energy saving capability to be used by the CU 201 so as to correspond to the determined power saving state (energy saving state IE) of the RU 300. The control device 100 can transmit the identification information of the energy saving capability as an energy saving control IE in the signal EN1. The CU 201 executes power saving control based on the identification information. Even if the control device 100 acquires information about the energy saving capability of the DU 202 in advance, it can similarly identify the energy saving capability of the DU 202 that corresponds to the determined power saving state of the RU 300 and transmit the identification information in the signal EN1. The DU 202 executes power saving control based on the specific information.

[0142] However, when the CU 201, rather than the control device 100, receives the signal EN1, it may generate specific information based on the energy saving state IE included in the signal EN1 and transmit the specific information included in the signal EN2. Similarly, when the DU 202 receives the signal EN2, it may generate specific information based on the energy saving state IE included in the signal EN2 and transmit the specific information included in the signal CI. In this case, the CU 201 or the DU 202 can recognize the target of power saving control in the RU 300 by receiving an energy saving capability report from the RU 300 in advance. The CU 201 or the DU 202 identifies, from the energy saving capabilities that are the target of power saving control in the CU 201, the energy saving capability that corresponds to the degree of power consumption reduction indicated by the energy saving state IE included in the received signal EN1 or EN2. For example, the CU201 or the DU202 may identify an energy saving capability that is expected to have a power consumption reduction effect corresponding to the energy saving state IE by comparing the energy saving state IE included in the received signal EN1 or EN2 with the associated information. Then, the CU201 or the DU202 can transmit information on the identified energy saving capability (specific information) as an energy saving control IE in the signal EN2 or CI.

[0143] If the CU 201 acquires information about the energy saving capability of the DU 202 in advance, the CU 201 can identify the target of power saving control in the DU 202 based on that information. Then, from among the energy saving capabilities that are the target of power saving control in the DU 202, the CU 201 identifies the energy saving capability that the DU 202 uses to reduce power consumption. For example, the CU 201 identifies the energy saving capability that the DU 202 uses so as to correspond to the energy saving state IE included in the signal EN1 or the energy saving control IE of the RU 300. Then, the CU 201 can transmit the identification information of that energy saving capability as an energy saving control IE included in the signal EN2. The DU 202 executes power saving control based on that identification information.

[0144] [Explanation of Effect] As described above, the signal CI can include specific information that identifies the energy saving capability used to reduce power consumption by the slave station equipment unit (RU) 300. This makes it possible for the slave station equipment unit (RU) 300 to perform processing appropriate for the current situation in order to perform power saving control.

[0145] Furthermore, at least one of the CU 201 and the DU 202 may receive a report from the slave station equipment (RU) 300 indicating an energy saving capability that allows at least the slave station equipment (RU) 300 to reduce power consumption. At least one of the CU 201 and the DU 202 may determine specific information based on this report. As a result, the CU 201 or the DU 202 performs power saving control after understanding the functions supported by the RU 300, thereby reliably achieving the power saving effect.

[0146] Here, when the CU 201 receives a report, the report may include the energy saving capability of the slave station equipment (RU) 300 and the energy saving capability of the DU 202 (relay unit) that relays between the slave station equipment (RU) 300 and the CU 201. This allows the CU 201 to execute power saving control for the DU 202 as well. Note that the DU 202 can also be configured as a device separate from the CU 201 (master station equipment).

[0147] Furthermore, at least one of the CU 201 and the DU 202 may transmit, from among the energy saving capabilities indicated in the report, functions excluding energy saving capabilities that the device itself does not support, to the control device 100. This prevents the control device 100 from executing power saving control for functions that the CU 201 or the DU 202 does not support, thereby making it possible to suppress redundant processing in the control.

[0148] From another perspective, the signal EN1 transmitted by the control device 100 can include specific information that identifies the energy saving capability used to reduce power consumption by the slave station equipment unit (RU) 300. This makes it possible for the slave station equipment unit (RU) 300 to perform processing appropriate for the current situation in order to perform power saving control.

[0149] The control device 100 may also receive from the CU 201 a report indicating functions for which power consumption can be reduced by at least one of the CU 201, the DU 202, or the slave station unit (RU) 300 (i.e., any node in the base station), and determine the specific information based on the report. This allows the control device 100 to perform power saving control after understanding the functions supported by the CU 201, the DU 202, or the slave station unit (RU) 300, thereby ensuring the achievement of power saving effects.

[0150] Furthermore, the control device 100 may present the contents of the report to the user, allow the user to select one or more energy saving capabilities from the presented energy saving capabilities, and generate the signal EN1 so that the selected energy saving capability is identified by the identification information. This allows the administrator to execute power saving control as desired.

[0151] Fifth Embodiment Next, variations (5-1) and (5-2) in which the control device 100 is not provided in the communication system (for example, the function of the control device 100 is included in the CU 201) will be described.

[0152] (5-1) Fig. 11 is a block diagram showing an example of a communication system. The communication system S2 has the same components as the communication system S1, except that the control device 100 is not provided.

[0153] The CU 201 acquires traffic information, which is a measurement value, as the communication state of the cell provided by the base station. Based on the acquired information, the CU 201 executes the same processing as that executed by the control device 100 in the third embodiment, and generates and outputs a signal EN2 having the same content as the signal EN1 in the third embodiment. Therefore, the signal EN2 can include the following IEs: Energy saving enable IE: {ON, OFF} Energy saving state IE: {S 25 ,S 50 ,S 75 ,S 100} In this example, the signal EN2 is an example of the first power-saving control signal in the first embodiment or the second power-saving control signal in the second embodiment.

[0154] The CU 201 also determines the relationship between the traffic values ​​and their fluctuations indicated by the traffic information and a predetermined threshold, and changes the energy saving status IE included in the signal EN1 based on the determination result. The details of this determination and change process are also as described in the third embodiment.

[0155] As described in the third embodiment, the communication status information may be reported by being periodically transmitted to the CU 201 (for example, at intervals of one minute or several minutes), or may be reported by being aperiodically transmitted to the CU 201. In addition, the CU 201 may define S0 in the above-mentioned energy saving state IE, which does not allow signal transmission or reception.

[0156] However, the CU 201 may determine only the above-described energy saving enable IE for the cell to be controlled and transmit it as signal EN2 to the DU 202. Alternatively, the CU 201 may determine the degree of power consumption reduction (energy saving state IE) in the RU 300, determine the energy saving control IE based on that, and transmit the energy saving control IE in the signal EN2 to the DU 202. In this case, it can be said that the DU 202 is provided with the functions of the control device 100 in the third embodiment.

[0157] The explanation of the DU 202 and the RU 300 is the same as in the third embodiment, and therefore will be omitted.

[0158] 12 is a sequence diagram showing an example of the operation of the communication system S2, and the operation of the entire communication system S2 will be described with reference to this diagram. Details of the processes executed by each device in the communication system S2 are as described above.

[0159] First, the CU 201 executes the above-mentioned determination based on the acquired communication status information of each RU 300 and changes the power saving control for the RU 300 (step S51). The change in power saving control includes at least one of changing the Energy saving enable IE from ON or OFF to the other, or changing the Energy saving status IE to a different parameter. The CU 201 transmits a signal En2 related to the changed power saving control to the DU 202 (step S52).

[0160] When DU 202 receives signal En2, it generates signal CI based on signal EN2 to cause RU 300 to perform power saving operation. Signal CI is an example of the first power saving control signal in embodiment 1. DU 202 transmits signal CI1 to RU 300A (step S53) and signal CI2 to RU 300B (step S54). When RU 300A receives signal CI1, it changes its operating mode based on signal CI1 (step S55). When RU 300B receives signal CI2, it changes its operating mode based on signal CI2 (step S56).

[0161] (5-1A) Fig. 13A is a block diagram showing a variation of a communication system. The communication system S2 in Fig. 13A differs from the configuration of the communication system S2 in Fig. 11 in that an RU 300C is cascade-connected to an RU 300B in cell 2 via an RU-RU cascade connection interface (e.g., an O-RAN interface). The CU 201 and DU 202 (master station 200) provide a common cell 2 by operating the RU 300B and RU 300C. The RU 300B forwards a signal CI2 transmitted from the DU 202 to the RU 300C via the RU-RU cascade connection interface. The RU 300C performs wireless communication with the UE 400C and changes its operation mode based on energy saving control information included in the signal CI2.

[0162] (5-1B) Figure 13B is a block diagram showing another variation of a communication system. The communication system S2 of Figure 13B differs from the configuration of Figure 13A in that RU 300C provides a different cell 3 from RU 300B. However, the process in which RU 300B transmits signal CI2 to RU 300C and RU 300C changes its operating mode based on the energy saving control information included in signal CI2 is the same. The configuration of RU 300B and RU 300C of Figure 13B can be realized, for example, by logically dividing a single RU into multiple RUs, each of which provides its own cell (RAN-Sharing).

[0163] (5-1C) FIG. 13C is a block diagram showing another variation of a communication system. The communication system S2 in FIG. 13C differs from the configuration in FIG. 13A in that a wireless repeater (RP) 301C, which is an example of a relay device, is provided instead of the RU 300C. The CU 201 and DU 202 (master station device 200) provide a common cell 2 by operating the RU 300B and RP 301C. The DU 202 payloads the signal CI2, for example, in Layer 2, superimposes it on a wireless channel of the Uu interface, and transmits it to the RU 300B. The RU 300B converts the wireless channel on which the signal CI2 is superimposed into a wireless signal and transmits the wireless signal to the RP 301C via the Uu interface (Uu2-1). However, the signal CI2 is not limited to Layer 2, and may be multiplexed as a payload of a higher layer, such as Layer 3. The signal CI2 destined for the RP 301C is transmitted as a radio signal from the DU 202 in this manner, and the RU 300B does not particularly recognize the signal CI2. Here, the signal CI2 is transmitted over a radio link called a control link within the Uu interface. The signal CI2 is transmitted to the RP 301C in the form of an RRC message, DCI format, MAC CE (Control Element), or the like, and terminated. The RU 300B changes its operation mode based on the energy saving control information included in the signal CI2. The RP 301C has the function of an RU that performs radio communication with the UE 400C, and changes its operation mode based on the energy saving control information included in the signal CI2.

[0164] (5-1D) FIG. 13D is a block diagram showing another variation of the communication system. The communication system S2 in FIG. 13D differs from the configuration in FIG. 13C in that an IAB (Integrated Access Backhaul) 302, which is another example of a relay device, is provided instead of the RP 301C. The IAB 302 includes an IAB-MT (Mobile Termination) 302B and an IAB-DU 302C. The DU 202 (master station 200) operates the RU 300B to provide cell 2. The CU 201 operates the IAB 302 via an upper layer on the Uu interface to provide cell 3. The CU 201 transmits the signal EN2 to the DU 202 as a signal of an upper layer (e.g., Layer 3) directed to the IAB 302. The DU 202 then transfers this signal as a payload to Layer 2, superimposes it on a radio channel of the Uu interface, and transmits it to the RU 300B. The RU 300B converts the radio channel on which the signal EN2 is superimposed into a radio signal and transmits the radio signal to the IAB-MT 302B via the Uu interface (Uu2). The signal EN2 for the IAB 302 is transmitted from the CU 201 as a higher layer signal, and the DU 202 and the RU 300B do not particularly recognize the signal EN2. The signal EN2 is transmitted from the IAB-MT 302B to the IAB-DU 302C. The IAB-DU 302C has a DU function and an RU function for performing radio communication with the UE 400C, and changes its operation mode based on the energy saving control information included in the signal EN2.

[0165] By combining (5-1A) to (5-1D), multiple devices may be connected to the RU 300B for the RU 300C or RP 301C device.

[0166] As described above, the signal CI2 can reduce the power consumption of not only the slave station equipment (RU) 300B, but also at least one of another slave station equipment (RU) 300C or RP 301C connected to the slave station equipment (RU) 300B. This expands the scope of targets for which power saving control is performed, improving the power saving effect.

[0167] (5-2A) Fig. 14A is a block diagram showing a variation of a communication system. The communication system S3 in Fig. 14A differs from the communication system S2 in Fig. 11 in that the RU 300B is managed by a master station device 200B that is different from the master station device 200A. The master station device 200B has a CU 201B and a DU 202B that have the same configuration as the master station device 200A.

[0168] The CU 201A acquires the communication status of not only the RU 300A but also the RU 300B, and generates a signal EN2 based on that information. The CU 201A transmits the signal EN2 to the CU 201B, for example, via the Xn interface. Details of how the CU 201A generates the signal EN2 for the RU 300B based on the communication status of the RU 300B are as described in (5-1). Alternatively, the CU 201A may generate the signal EN1 described in the third embodiment, instead of the signal EN2, based on the communication status of the RU 300B, and transmit the signal EN1 to the CU 201B. Upon receiving the signal EN1 from the CU 201A, the CU 201B generates a signal EN2 for the DU 202B using the method described in the third embodiment, and transmits the signal EN2 to the DU 202B. Details of how the CU 201A generates the signal EN1 and how the DU 202B generates the signal EN1 are as described in the third embodiment.

[0169] The CU 201B transmits a signal EN2 to the DU 202B. Based on the signal EN2, the DU 202B generates a signal CI2 for causing the RU 300B to perform a power saving operation, and transmits the signal CI2 to the RU 300B. The RU 300B changes its operation mode based on the energy saving control information included in the signal CI2. In this way, the master station device 200B performs power saving control of the subordinate RU 300B. Note that the details of each process have already been described, so a detailed explanation will be omitted.

[0170] (5-2B) Fig. 14B is a block diagram showing another variation of the communication system. The communication system S3 in Fig. 14B differs from the configuration in Fig. 14A in that the master station device 200B does not include a CU 201B.

[0171] The CU 201A acquires the communication status of not only the RU 300A but also the RU 300B, and generates a signal EN2 based on that information. The CU 201A transmits the signal EN2 to the DU 202B via, for example, the Xn interface.

[0172] Based on the signal EN2, the DU 202B generates a signal CI2 for causing the RU 300B to perform a power saving operation, and transmits the signal CI2 to the RU 300B. The RU 300B changes its operation mode based on the energy saving control information included in the signal CI2.

[0173] The above-described connection configurations of RU 300C, RP 301C, or IAB 302 to RU 300B in (5-1A) to (5-1D) and the configurations in which master station device 200B is located in (5-2A) to (5-2B) can be similarly applied to embodiment 3. That is, even when a control device 100 is provided, the configurations in (5-1A) to (5-2B) can be applied.

[0174] Note that the present disclosure is not limited to the above-described embodiments and may be modified as appropriate without departing from the spirit and scope of the present disclosure. For example, the technology described in the present disclosure is not limited to dedicated communication devices and may be applied to any device having a communication function. Furthermore, in the present disclosure, a user equipment (UE) (including a mobile station, mobile terminal, mobile device, or wireless device) is an entity connected to a network via a wireless interface.

[0175] The processing of the master station device 10 in the first embodiment may be implemented using a rule-based algorithm or a pre-trained AI (artificial intelligence) model. This AI model is trained by inputting training data including multiple sets of communication states between slave station devices and user terminals and power-saving control instructions for the slave station devices, which serve as correct labels. Similarly, the processing of the control device 30 in the second embodiment may be implemented using a rule-based algorithm or a pre-trained AI model. This AI model is trained by inputting training data including multiple sets of communication states between wireless communication units and user terminals and power-saving control instructions, which serve as correct labels. Examples of communication states include, but are not limited to, numerical values ​​such as traffic information, wireless resource usage rates, and the length of scheduling queues for user terminals. Examples of power-saving control instructions include, but are not limited to, at least one of energy saving enable, energy saving state (degree of power consumption reduction), and energy saving control.

[0176] For the control device 100, CU 201, and DU 202 in embodiment 3, these processes may be realized by a rule-based algorithm, or may be realized by an AI model that has undergone pre-training similar to that described above.

[0177] (Hardware Configuration Example) In the above-described embodiment, this disclosure has been described as a hardware configuration, but this disclosure is not limited to this. This disclosure can also be realized by having a processor in a computer execute a computer program to perform the processing (steps) of each device or control device of the base station described in the above-described embodiment.

[0178] 15 is a block diagram showing an example of the hardware configuration of an information processing device (signal processing device) that executes the processing of the present disclosure described above. Referring to FIG. 15 , this information processing device 90 includes a signal processing circuit 91, a processor 92, and a memory 93.

[0179] The signal processing circuit 91 is a circuit for processing signals under the control of the processor 92. The signal processing circuit 91 may also include a communication circuit for transmitting and receiving signals to and from other devices. The communication circuit may include, for example, a network interface card (NIC) that complies with the IEEE (Institute of Electrical and Electronics Engineers) 802.3 series.

[0180] The processor 92 is connected (coupled) to the memory 93, and performs the processing of the device described in the above embodiment by reading and executing software (computer programs) from the memory 93. As an example of the processor 92, one of a CPU (Central Processing Unit), an MPU (Micro Processing Unit), an FPGA (Field-Programmable Gate Array), a DSP (Demand-Side Platform), and an ASIC (Application Specific Integrated Circuit) may be used, or a plurality of these may be used in parallel.

[0181] The memory 93 may be a volatile memory, a nonvolatile memory, or a combination thereof. The memory 93 is not limited to one, and may be provided in multiple units. The volatile memory may be, for example, a random access memory (RAM) such as a dynamic random access memory (DRAM) or a static random access memory (SRAM). The nonvolatile memory may be, for example, a read only memory (ROM) such as a programmable random only memory (PROM) or an erasable programmable read only memory (EPROM), a flash memory, or a solid state drive (SSD).

[0182] The memory 93 is used to store one or more instructions. Here, the one or more instructions are stored as a group of software modules in the memory 93. The processor 92 can perform the processes described in the above embodiments by reading and executing the group of software modules from the memory 93.

[0183] The memory 93 may include a memory provided outside the processor 92, as well as a memory built into the processor 92. The memory 93 may also include a storage device located away from the processors constituting the processor 92. In this case, the processor 92 can access the memory 93 via an I / O (Input / Output) interface.

[0184] As described above, one or more processors included in each device in the above-described embodiments execute one or more programs including instructions for causing a computer to execute the algorithms described using the drawings. This processing enables the signal processing method described in each embodiment to be realized.

[0185] The program includes instructions (or software code) that, when loaded into a computer, cause the computer to perform one or more functions described in the embodiments. The program may be stored on a non-transitory computer-readable medium or a tangible storage medium. By way of example and not limitation, computer-readable media or tangible storage media include random-access memory (RAM), read-only memory (ROM), flash memory, solid-state drive (SSD) or other memory technologies, CD-ROM, digital versatile disk (DVD), Blu-ray disc or other optical disk storage, magnetic cassette, magnetic tape, magnetic disk storage or other magnetic storage device. The program may also be transmitted on a transitory computer-readable medium or communication medium. By way of example and not limitation, transitory computer-readable media or communication media include electrical, optical, acoustic, or other forms of propagated signals.

[0186] Some or all of the above embodiments can be described as, but are not limited to, the following supplementary notes. (Supplementary Note 1) A base station master station device comprising: a processor; and a transceiver, wherein the processor is configured to cause the transceiver to transmit power saving control information for reducing power consumption of a slave station device of the base station that wirelessly communicates with a user terminal. (Supplementary Note 2) The base station master station device according to Supplementary Note 1, wherein the processor changes a degree of reduction in power consumption of the slave station device, which is reduced by the power saving control information, based on a communication state between the slave station device and the user terminal. (Supplementary Note 3) The base station master station device according to Supplementary Note 2, wherein the information indicating the communication state is information indicating a usage rate of wireless resources in communication between the user terminal and the slave station device. (Supplementary Note 4) The base station master station device according to Supplementary Note 2, wherein the information indicating the communication state is information indicating a traffic volume in communication between the user terminal and the slave station device. (Supplementary Note 5) The parent station device of a base station according to any one of Supplementary Notes 1 to 4, wherein the power saving control information includes information for controlling a radio signal communicated between the slave station device and the user terminal. (Supplementary Note 6) The parent station device of a base station according to Supplementary Note 5, wherein the power saving control information controls at least one of turning on or off a symbol in a time slot of the radio signal, a maximum modulation degree of the radio signal, or a frequency related to the radio signal. (Supplementary Note 7) The parent station device of a base station according to any one of Supplementary Notes 1 to 6, wherein the power saving control information includes specification information for specifying a function used by the slave station device to reduce power consumption. (Supplementary Note 8) The parent station device of a base station according to Supplementary Note 7, wherein the transceiver receives, from the slave station device, a report indicating functions for which the slave station device can reduce power consumption, and the processor determines the specification information based on the report. (Supplementary Note 9) The master station device of the base station according to Supplementary Note 8, wherein the report indicates a function that can reduce power consumption of the slave station device and a function that can reduce power consumption of a relay device that relays between the slave station device and the master station device.(Supplementary Note 10) The parent station device of a base station according to Supplementary Note 8, wherein the transceiver transmits functions indicated in the report, excluding functions not supported by the parent station device, to a control device of the parent station device. (Supplementary Note 11) The parent station device of a base station according to any one of Supplements 1 to 10, wherein the transceiver receives an enable signal for reducing power consumption of the child station devices from an external control device, and the processor generates the power saving control information based on the enable signal. (Supplementary Note 12) The parent station device of a base station according to any one of Supplements 1 to 11, wherein the power saving control information is control information for reducing power consumption of the child station devices and at least one of another child station device or a relay device connected to the child station devices. (Supplementary Note 13) A control device comprising: a processor; and a transceiver, wherein the processor is configured to cause the transceiver to transmit power saving control information for a base station having a wireless communication unit that wirelessly communicates with a user terminal, for reducing power consumption of the wireless communication unit. (Supplementary Note 14) The control device according to Supplementary Note 13, wherein the processor changes a degree of reduction in power consumption of the wireless communication unit, which is reduced by the power saving control information, based on a communication state between the wireless communication unit and the user terminal. (Supplementary Note 15) The control device according to Supplementary Note 14, wherein the information indicating the communication state is information indicating a usage rate of wireless resources in communication between the user terminal and the wireless communication unit. (Supplementary Note 16) The control device according to Supplementary Note 14, wherein the information indicating the communication state is information indicating a traffic volume in communication between the user terminal and the wireless communication unit. (Supplementary Note 17) The control device according to any one of Supplements 13 to 16, wherein the power saving control information includes information for controlling a wireless signal communicated between the wireless communication unit and the user terminal. (Supplementary Note 18) The control device according to Supplementary Note 17, wherein the power saving control information controls at least one of turning on or off a symbol in a time slot of the wireless signal, a maximum modulation degree of the wireless signal, or a frequency related to the wireless signal.(Supplementary Note 19) The control device according to any one of Supplementary Notes 13 to 18, wherein the power saving control information includes specification information that specifies a function used by the wireless communication unit to reduce power consumption. (Supplementary Note 20) The control device according to Supplementary Note 19, wherein the transceiver receives from the base station a report indicating functions for which the base station can reduce power consumption, and the processor determines the specification information based on the report. (Supplementary Note 21) The control device according to Supplementary Note 20, wherein the processor presents contents of the report to a user, allows the user to select one or more functions from the presented functions, and generates the power saving control information such that the selected functions are specified by the specification information. (Supplementary Note 22) The control device according to any one of Supplementary Notes 13 to 21, wherein the transceiver transmits the power saving control information for reducing power consumption of a slave station device having the wireless communication unit in the base station to a master station device of the base station. (Supplementary Note 23) The control device according to Supplementary Note 22, wherein the power saving control information is control information for reducing power consumption of the slave station device and at least one of another slave station device or a relay device connected to the slave station device. (Supplementary Note 24) The control device according to Supplementary Note 22 or 23, wherein the power saving control information includes an enable signal for reducing power consumption of the slave station device. (Supplementary Note 25) A communication system comprising: a master station device of a base station; and a slave station device of the base station, wherein the master station device comprises a first processor and a first transceiver, wherein the first processor is configured to cause the first transceiver to transmit power saving control information for reducing power consumption of the slave station device that wirelessly communicates with a user terminal, and the slave station device comprises a second processor and a second transceiver, wherein the second processor is configured to cause the second transceiver to receive the power saving control information from the master station device. (Supplementary Note 26) The communication system according to Supplementary Note 25, wherein the first processor changes a degree of reduction in power consumption of the slave station device indicated by the power saving control information based on a communication state between the slave station device and the user terminal.(Supplementary Note 27) A communication system comprising: a control device; and a base station, wherein the control device comprises: a first processor; and a first transceiver, wherein the first processor is configured to cause the first transceiver to transmit power save control information to the base station having a wireless communication unit that communicates wirelessly with a user terminal, for reducing power consumption of the wireless communication unit, and the base station comprises: a second processor; and a second transceiver, wherein the second processor is configured to cause the second transceiver to receive the power save control information from the control device. (Supplementary Note 28) The communication system according to Supplementary Note 27, wherein the first processor changes a degree of reduction in power consumption of the wireless communication unit indicated by the power save control information, based on a communication state between the wireless communication unit and the user terminal. (Supplementary Note 29) A method executed by a master station device of a base station, comprising transmitting power save control information for reducing power consumption of a slave station device of the base station that communicates wirelessly with a user terminal. (Supplementary Note 30) A method executed by a control device, comprising transmitting, with respect to a base station having a wireless communication unit that communicates wirelessly with a user terminal, power saving control information for reducing the power consumption of the wireless communication unit. (Supplementary Note 31) A program that causes a computer to execute the following: transmitting, with respect to a base station having a wireless communication unit that communicates wirelessly with a user terminal, power saving control information for reducing the power consumption of the wireless communication unit. (Supplementary Note 32) A program that causes a computer to execute the following: transmitting, with respect to a base station having a wireless communication unit that communicates wirelessly with a user terminal, power saving control information for reducing the power consumption of the wireless communication unit.

[0187] Although the present disclosure has been described above with reference to the embodiments, the present disclosure is not limited to the above. Various modifications that can be understood by a person skilled in the art can be made to the configuration and details of the present disclosure within the scope of the disclosure.

[0188] This application claims priority based on Japanese Patent Application No. 2022-128024, filed on August 10, 2022, the disclosure of which is incorporated herein in its entirety by reference.

[0189] B1 Base station 10 Master station device 11 Communication unit 12 Control unit 20 Slave station device 30 Control device 31 Communication unit 32 Control unit 40 Base station S1 Communication system 100 Control device 200 Master station device 201 CU 202 DU 300 Slave station device (RU) 301 RP 302 IAB 400 UE

Claims

1. A processor; A transceiver, The processor, for the transceiver, and transmitting power saving control information for reducing power consumption of a slave station device of a base station that wirelessly communicates with a user terminal. Base station master station equipment.

2. the processor changes a degree of reduction in the power consumption of the slave station device, which is reduced by the power saving control information, based on a communication state between the slave station device and the user terminal; The master station device of the base station according to claim 1.

3. the information indicating the communication state is information indicating a usage rate of wireless resources in communication between the user terminal and the slave station device; The master station device of the base station according to claim 2.

4. A processor; A transceiver, The processor, for the transceiver, A base station having a wireless communication unit that wirelessly communicates with a user terminal is configured to transmit power saving control information for reducing power consumption of the wireless communication unit. Control device.

5. The processor changes a degree of reduction in power consumption of the wireless communication unit, which is reduced by the power saving control information, based on a communication state between the wireless communication unit and the user terminal. The control device according to claim 4.

6. The information indicating the communication state is information indicating a usage rate of wireless resources in communication between the user terminal and the wireless communication unit. The control device according to claim 5.

7. transmitting power saving control information for reducing power consumption of a slave station device of a base station that wirelessly communicates with a user terminal; A method performed by a master station device of a base station.

8. transmitting power saving control information for reducing power consumption of a wireless communication unit of a base station that wirelessly communicates with a user terminal; A method performed by a controller.

9. Transmitting power saving control information for reducing power consumption of a slave station device of a base station that wirelessly communicates with the user terminal; A program that causes a computer to do something.

10. Transmitting power saving control information for reducing power consumption of a wireless communication unit of a base station that wirelessly communicates with a user terminal; A program that causes a computer to do something.