Base station and control method thereof

Abstract

To appropriately reduce power consumption according to the number of connected user devices.SOLUTION: A base station capable of communicating with a plurality of pieces of user equipment (UE) via a wireless communication system includes an RLC layer (Radio Link Control layer), a MAC layer (Medium Access Control layer), and a PHY layer (Physical layer), and the PHY layer includes a common processing unit that performs common processing for the plurality of pieces of connected user equipment, and a plurality of user processing units that perform specific processing for each of the connected user equipment, and among the plurality of user processing units, power is supplied to the user processing unit that is connected to the user equipment, and power is not supplied to the user processing unit that is not connected to the user equipment.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a base station and a method for controlling a base station. [Background technology]

[0002] Recently, fifth-generation mobile communication systems, also known as 5G (5th Generation), have been attracting attention as they can be used by various entities according to regional or individual needs.

[0003] Non-Patent Document 1 shows an example in which the functions of the PHY (Physical) layer are divided between an RU (Radio Unit) and a DU (Distributed Unit) in fifth-generation mobile communications. Non-Patent Document 2 shows a specific example of dividing the functions of the PHY layer. The signal processing unit that executes the functions of the PHY layer provided in the DU is also called the H-PHY (High-Physical) layer. [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] O-RAN Working Group 8 Base Station O-DU and O-CU Software Architecture and APIs [Non-patent document 2] O-RAN Working Group 4 (Open Fronthaul Interfaces WG)Control, User and Synchronization Plane Specification Summary of the Invention [Problem to be solved by the invention]

[0005] In the past, in the H-PHY layer, an accelerator with the computational resources to process all of the user equipment (UE) up to the maximum number of user equipments connected to the base station was allocated to process all of the user equipments at once. Therefore, when the number of user equipments connected to the base station is less than the maximum number, excessive computational resources are allocated, resulting in unnecessary power consumption.

[0006] The present invention has been made in consideration of the above-mentioned points, and has an object to provide a technique that can suitably reduce power consumption according to the number of connected user devices. [Means for solving the problem]

[0007] One aspect of the present invention is a base station capable of communicating with a plurality of user equipment (UE) via a wireless communication system, comprising an RLC layer (Radio Link Control layer), a MAC layer (Medium Access Control layer), and a PHY layer (Physical layer), wherein the PHY layer comprises a common processing unit that performs common processing for a plurality of connected user equipment, and a plurality of user processing units that perform specific processing for each of the connected user equipment, and wherein, of the plurality of user processing units, power is supplied to the user processing unit that is connected to the user equipment, and power is not supplied to the user processing unit that is not connected to the user equipment.

[0008] In one aspect of the present invention, each of the user processing units is connected to a plurality of the user devices, and the maximum number of the user devices that can be simultaneously connected to each of the user processing units is predetermined.

[0009] In one aspect of the present invention, the maximum number of user devices that can be simultaneously connected to the user processing unit varies depending on the area in which the user devices are installed.

[0010] In one aspect of the present invention, the common processing unit receives a signal used to establish a connection with the user equipment using a physical random access channel (PRACH) in uplink communication with the user equipment.

[0011] In one aspect of the present invention, the user processing unit receives user data of the connected user equipment using a PUSCH (Physical Uplink Shared Channel) in uplink communication with the user equipment.

[0012] In one aspect of the present invention, the common processing unit performs precoding processing on signals transmitted from the respective user processing units before transmitting the signals to the user equipment.

[0013] In addition, in one aspect of the present invention, the common processing unit transmits a signal used for connecting with the user equipment in downlink communication with the user equipment, and the signal used for connecting with the user equipment includes a synchronization signal (SS) transmitted from the base station to the user equipment indicating a signal detection timing, and a broadcast signal transmitted using a PBCH (Physical Broadcast Channel).

[0014] In one aspect of the present invention, the user processing unit transmits user data of the connected user equipment using a PDSCH (Physical Downlink Shared Channel) in downlink communication with the user equipment.

[0015] In addition, in one aspect of the present invention, the common processing unit and each of the user processing units are provided separately and independently as a node lower than a DU (Distributed Unit) having at least a MAC layer, and a node higher than an RU (Radio Unit) in the PHY layer that controls an antenna and communicates with the user equipment.

[0016] Another aspect of the present invention is a method for controlling a base station capable of communicating with a plurality of user equipment (UE) via a wireless communication system, the base station comprising an RLC layer (Radio Link Control layer), a MAC layer (Medium Access Control layer), and a PHY layer (Physical layer), the PHY layer comprising a common processing unit that performs common processing for a plurality of connected user equipment, and a plurality of user processing units that perform specific processing for each of the connected user equipment, the method comprising: supplying power to the user processing unit that is connected to the user equipment, and not supplying power to the user processing unit that is not connected to the user equipment. [Effects of the Invention]

[0017] According to the present invention, it is possible to reduce power consumption appropriately according to the number of connected user devices. [Brief explanation of the drawings]

[0018] [Figure 1] 1 is a diagram illustrating an example of a configuration of a wireless communication system according to a first embodiment. [Figure 2] FIG. 2 is a diagram illustrating an example of functional division of a base station according to the first embodiment. [Figure 3] 2 is a diagram illustrating a first example of functional division of an O-DU according to the first embodiment during uplink communication. FIG. [Figure 4] FIG. 10 is a diagram illustrating a second example of functional division of an O-DU according to the first embodiment during uplink communication. [Figure 5]FIG. 10 is a diagram illustrating a third example of functional division during uplink communication for an O-DU according to the first embodiment. [Figure 6] FIG. 10 is a diagram illustrating a fourth example of functional division of an O-DU according to the first embodiment during uplink communication. [Figure 7] 2 is a diagram illustrating a first example of functional division during downlink communication for an O-DU according to the first embodiment. FIG. [Figure 8] FIG. 10 is a diagram illustrating a second example of functional division during downlink communication for an O-DU according to the first embodiment. [Figure 9] FIG. 10 is a diagram illustrating a third example of functional division during downlink communication for an O-DU according to the first embodiment. [Figure 10] 6 is a flowchart illustrating an example of processing performed by a base station according to the first embodiment. [Figure 11] FIG. 10 is a diagram illustrating an example of functional division of a base station according to a second embodiment. [Figure 12] FIG. 2 is a block diagram showing an example of the internal configuration of a base station according to the present embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0019] [Embodiment 1] A preferred embodiment of a base station and a base station control method according to the present invention will be described in detail below with reference to the accompanying drawings. In the drawings, identical or similar parts are designated by identical or similar reference numerals. Note that the present invention is not limited to these embodiments and includes various modifications and improvements. In other words, the components described below include those that can be easily imagined by a person skilled in the art and those that are substantially identical, and the components described below can be combined as appropriate. Furthermore, various omissions, substitutions, or modifications of the components of the present embodiment may be made without departing from the spirit of the present invention.

[0020] [Configuration of wireless communication system 10] First, a wireless communication system 10 will be described with reference to FIG.

[0021] Fig. 1 is a diagram illustrating an example of a configuration of a wireless communication system 10 according to the first embodiment. The wireless communication system 10 includes a base station 100 and a plurality of user equipments 200. In Fig. 1, user equipments 200-1 to 200-3 illustrate the plurality of user equipments 200. Hereinafter, when the user equipments 200-1 to 200-3 are not distinguished from each other, they may be simply referred to as user equipments 200.

[0022] The base station 100 can communicate with each user device 200 via an antenna provided in the base station 100. The base station 100 is, for example, a next generation Node B (gNB). The base station 100 performs wireless communication with each user device 200 and provides various services to each user device 200.

[0023] The base station 100 may also be a device included in a local 5G system. The local 5G system may be a non-public cellular network. The non-public cellular network may be an example of an NPN (Non Public Network). The local 5G system may be a 5G system built within a building or on land by the owner of the building or land. In this case, the wireless communication system 10 according to the embodiment is an example of a non-public cellular network.

[0024] The user device 200 is an information processing device. The user device 200 may be, for example, a smartphone, a feature phone, an IoT (Internet of Things) device, a personal computer, a vehicle or a device provided in a vehicle, an aircraft or a device provided in an aircraft, etc. The user device 200 may also be referred to as UE (User Equipment).

[0025] [Configuration of base station 100] 1, base station 100 includes an O-CU (Open-Centralized Unit) 110, multiple O-DUs (Open-Distributed Units) 120, and multiple O-RUs (Open-Radio Units) 130. The multiple O-DUs 120 may be referred to as O-DU120-1 and O-DU120-2, respectively. The multiple O-RUs 130 may be referred to as O-RU130-1, O-RU130-2, O-RU130-3, and O-RU130-4, respectively.

[0026] The O-CU110 may be referred to as an aggregation unit. The O-CU110 controls the connected O-DU120. Specifically, the O-CU110 is connected to each of the O-DU120-1 and O-DU120-2 and controls each of the O-DU120-1 and O-DU120-2. The O-CU110 may be connected to an external network to transmit and receive data.

[0027] O-DU 120 is sometimes referred to as a distributed unit. O-DU 120-1 is connected to O-CU 110, O-RU 130-1, and O-RU 130-2, and controls O-RU 130-1 and O-RU 130-2. O-DU 120-2 is connected to O-CU 110, O-RU 130-3, and O-RU 130-4, and controls O-RU 130-3 and O-RU 130-4.

[0028] The O-RU 130 may also be referred to as a radio unit. The O-RU 130 is controlled by the O-DU 120 and performs radio communication in a predetermined manner, such as time division duplex (TDD) or frequency division duplex (FDD). The O-RU 130 controls antennas provided in the base station to perform downlink (DL) communication from the base station 100 to the user equipment 200 and uplink (UL) communication from the user equipment 200 to the base station 100.

[0029] In the base station 100 according to the embodiment, the O-RAN (Open Radio Access Network) fronthaul specification may be adopted between the O-DU 120 and the O-RU 130. The O-RAN is a specification established by the O-RAN Alliance, which includes multiple telecommunications carriers. However, other communication protocols may also be used between the O-DU 120 and the O-RU 130, and the communication is not limited to the example of using the O-RAN fronthaul specification (hereinafter, sometimes referred to as "O-RAN").

[0030] [Overview of functional division] FIG. 2 is a diagram illustrating an example of functional division of the base station 100 according to the first embodiment.

[0031] The O-CU 110 can perform the functions of a Service Data Adaptation Protocol (SDAP) layer 111, a Radio Resource Control (RRC) layer 112, and a Packet Data Convergence Protocol (PDCP) layer 113.

[0032] The O-DU 120 can also perform the functions of an RLC (Radio Link Control) layer 121, a MAC (Media Access Control) layer 122, and part of a PHY (Physical) layer. Of the PHY layer functions, the H-PHY (High-Physical) layer functions provided in the O-DU 120 are performed by a CH-PHY (Common High-Physical) layer 123 and multiple UH-PHY (User-centric High-Physical) layers 124. UH-PHY layers 124-1 and 124-2 exemplify multiple UH-PHY layers 124. Hereinafter, when the UH-PHY layers 124-1 and 124-2 are not distinguished from each other, they may be simply referred to as the UH-PHY layer 124. Note that while the same figure shows an example in which two UH-PHY layers 124 are provided, the number of UH-PHY layers 124 is arbitrary. The number of UH-PHY layers 124 may differ for each base station 100. By dividing the functions of the UH-PHY layer within the O-DU 120, the base station 100 can reduce processing delays caused by dividing the functions.

[0033] The CH-PHY layer 123 performs common processing for multiple user devices 200 connected to the base station 100. The CH-PHY layer 123 is also referred to as a common processing unit. Power is supplied to the CH-PHY layer 123 regardless of whether or not there is a user device 200 connected to the base station 100.

[0034] The UH-PHY layer 124 performs processing specific to each of the user equipment devices 200 connected to the base station 100. The UH-PHY layer 124 is also referred to as a user processing unit. Power is supplied to the UH-PHY layer 124 connected to the user equipment device 200, but power is not supplied to the user equipment device 200 not connected to the user equipment device 200. In other words, power is not supplied to the UH-PHY layer 124 not connected to the user equipment device 200 and not performing processing. As a result, the base station 100 does not supply power to the UH-PHY layer 124 not connected to the user equipment device 200 and not performing processing. By not supplying power to the UH-PHY layer 124 not connected to the user equipment device 200, the base station 100 can allocate appropriate computational resources according to the number of user equipment devices 200. Therefore, the base station 100 according to the embodiment can effectively reduce unnecessary power consumption due to excessive allocation of computational resources.

[0035] The UH-PHY layer 124 may be started up for each user equipment 200. In other words, the maximum number of user equipment 200 that can be simultaneously connected to the UH-PHY layer 124 may be one. This allows the base station 100 to accurately allocate computational resources according to the number of connected user equipment 200. By allocating computational resources appropriate for processing by the user equipment 200, the base station 100 can reduce unnecessary power consumption.

[0036] Alternatively, the UH-PHY layer 124 may be activated for each predetermined number of user equipment devices 200. That is, the maximum number of user equipment devices 200 that can be simultaneously connected to the UH-PHY layer 124 may be plural and may be predetermined. The base station 100 according to the embodiment sets the maximum number of user equipment devices 200 that can be processed by each UH-PHY layer 124, thereby allocating computational resources according to the number of connected user equipment devices 200 while reducing the number of UH-PHY layers 124. By reducing the number of UH-PHY layers 124, the base station 100 can reduce the number of times it controls whether or not power is supplied to the UH-PHY layers 124, making the control relatively simple.

[0037] Furthermore, the maximum number of user equipment devices 200 simultaneously connected to the UH-PHY layer 124 may vary depending on the region in which the base station 100 is installed. In densely populated areas, such as urban areas, the number of mobile users is relatively large, and the number of user equipment devices 200 connected to the base station 100 is likely to fluctuate. Therefore, in densely populated areas, by increasing the maximum number of user equipment devices 200 simultaneously connected to the UH-PHY layer 124, it is possible to reduce the frequency of control over whether or not power is supplied to the UH-PHY layer 124 while allocating computational resources according to the number of user equipment devices 200. On the other hand, in sparsely populated areas, such as rural areas, the number of mobile users is relatively small, and the number of user equipment devices 200 connected to the base station 100 is unlikely to fluctuate. Therefore, in sparsely populated areas, by reducing the maximum number of user equipment devices 200 simultaneously connected to the UH-PHY layer 124, it is possible to accurately allocate computational resources according to the number of user equipment devices 200. Therefore, the base station 100 according to the embodiment can reduce unnecessary power consumption.

[0038] The O-RU 130 can execute some of the PHY layer functions. Hereinafter, the signal processing unit that executes the PHY layer functions provided in the O-RU 130 may be referred to as the Low-PHY layer.

[0039] [Functional division of O-DU120 during uplink communication] A first example of functional division between the CH-PHY layer 123 and the UH-PHY layer 124 during uplink communication will be specifically described with reference to FIG.

[0040] Fig. 3 is a diagram showing a first example of functional division during uplink communication for the O-DU 120 according to embodiment 1. Fig. 3 shows a specific example of functional division among a CH-PHY layer 123, a UH-PHY layer 124, and a Low-PHY layer.

[0041] The CH-PHY layer 123 performs processing related to a physical random access channel (PRACH), a physical uplink control channel (PUCCH), and a sounding reference signal (SRS).

[0042] The PRACH is a channel for uplink communication from the user equipment 200 to the base station 100. The CH-PHY layer 123 receives a random access preamble using the PRACH as a signal used to establish a connection with the user equipment 200. The PRACH is used for processing to detect the user equipment 200. Therefore, processing using the PRACH is performed before a connection with the user equipment 200 is established. By having the CH-PHY layer 123 perform processing that is performed before a connection with the user equipment 200 is established, the UH-PHY layer 124 does not need to perform processing when not connected to the user equipment 200. Therefore, the base station 100 can cut off the supply of power to the UH-PHY layer 124 that is not connected to the user equipment 200. Therefore, the base station 100 according to the embodiment can suitably suppress unnecessary power consumption due to allocation of excessive computational resources.

[0043] The PUCCH is a channel for uplink communication from the user equipment 200 to the base station 100. The CH-PHY layer 123 receives, using the PUCCH, Acknowledgement (Ack) / Negative Acknowledgement (Nack), which are response signals to downlink transmissions. The CH-PHY layer 123 also receives a Channel Quality Indicator (CQI) report using the PUCCH. The CQI is quality information indicating the quality of received data or the quality of a communication path. The CH-PHY layer 123 also receives a Scheduling Request (SR) using the PUCCH. The amount of calculation required for processing using the PUCCH does not change significantly in proportion to the number of user equipments 200. Therefore, by collectively performing processing using the PUCCH in the CH-PHY layer 123, the amount of calculation required for the entire base station 100 can be reduced.

[0044] The SRS is a signal for uplink communication from the user equipment 200 to the base station 100. The CH-PHY layer 123 receives the SRS, which is a reference signal used for channel estimation. In "Cell-Free massive MIMO (Multiple Input Multiple Output)," by using the channel estimation results of the user equipment 200 to which the signal is to be transmitted as well as the channel estimation results of other user equipment 200, it is possible to prevent a signal transmitted to the target user equipment 200 from interfering with the other user equipment 200. In "Cell-Free massive MIMO," when the UH-PHY layer 124 performs channel estimation processing, each UH-PHY layer 124 performs channel estimation for its own user equipment 200. This may result in overlapping processing between the UH-PHY layers 124. By having the CH-PHY layer 123 collectively perform processing using the SRS, it is possible to reduce the overall computational load of the base station 100.

[0045] The UH-PHY layer 124 performs processing related to a PUSCH (Physical Uplink Shared CHannel).

[0046] The PUSCH is a channel for uplink communication from the user equipment 200 to the base station 100. An uplink shared channel (UL-SCH) is mapped to the PUSCH. The UH-PHY layer 124 receives user data and information for controlling higher layers using the PUSCH. The computational resources required for processing the PUSCH vary significantly depending on the number of connected user equipment 200. By supplying power to the UH-PHY layer 124 that processes the PUSCH and not supplying power to the UH-PHY layer 124 that does not process the PUSCH, the base station 100 can allocate appropriate computational resources according to the number of user equipment 200. Therefore, the base station 100 according to the embodiment can effectively reduce unnecessary power consumption due to allocation of excessive computational resources.

[0047] [Variation of functional division of O-DU 120 during uplink communication] The base station 100 according to the embodiment does not necessarily need to divide the functions of the O-DU 120 as shown in Fig. 3. Even if the functions of the O-DU 120 are divided as shown in the following Figs. 4 to 6, the base station 100 according to the embodiment can preferably suppress unnecessary power consumption due to allocation of excessive computational resources.

[0048] Fig. 4 is a diagram showing a second example of functional division during uplink communication for the O-DU 120 according to the first embodiment. Fig. 4 differs from the example of functional division shown in Fig. 3 in that the UH-PHY layer 124 performs processing using the PUCCH. That is, the functions of the O-DU 120 may be divided so that the CH-PHY layer 123 performs processing using the PRACH and processing using the SRS, and the UH-PHY layer 124 performs processing using the PUCCH and processing using the PUSCH.

[0049] Fig. 5 is a diagram showing a third example of functional division during uplink communication for the O-DU 120 according to the first embodiment. Fig. 5 differs from the example of functional division shown in Fig. 3 in that the UH-PHY layer 124 performs processing using the SRS. That is, the functions of the O-DU 120 may be divided so that the CH-PHY layer 123 performs processing using the PRACH and processing using the PUCCH, and the UH-PHY layer 124 performs processing using the PUSCH and processing using the SRS.

[0050] Fig. 6 is a diagram showing a fourth example of functional division during uplink communication for the O-DU 120 according to the first embodiment. Fig. 6 differs from the example of functional division shown in Fig. 3 in that the UH-PHY layer 124 performs processing using the PUCCH and SRS. That is, the functions of the O-DU 120 may be divided so that the CH-PHY layer 123 performs processing using the PRACH, and the UH-PHY layer 124 performs processing using the PUCCH, processing using the PUSCH, and processing using the SRS.

[0051] [Modification of functional division of O-DU120 during downlink] Next, a first example of functional division between the CH-PHY layer 123 and the UH-PHY layer 124 during downlink communication will be specifically described with reference to FIG.

[0052] FIG. 7 is a diagram illustrating a first example of functional division during downlink communication for the O-DU 120 according to the first embodiment.

[0053] The CH-PHY layer 123 performs precoding and other processes related to a PSS (Primary Synchronization Signal), an SSS (Primary Synchronization Signal), a PBCH (Primary Synchronization Signal), a PDCCH (Physical Downlink Control channel), and a PDSCH (Physical Downlink Shared CHannel). In the following description, the PSS and SSS may be collectively referred to as a synchronization signal (SS).

[0054] The synchronization signal is a signal for downlink communication from the base station 100 to the user equipment 200. The CH-PHY layer 123 transmits the synchronization signal indicating the detection timing of the signal. The synchronization signal is assigned a synchronization code that corresponds one-to-one to a PCI (Physical Cell ID) assigned to each cell. Based on the received synchronization signal, the user equipment 200 controls scheduling (resource allocation) of system information, downlink data signals (e.g., signals transmitted using PDSCH), and downlink control signals (e.g., signals including acknowledgement information transmitted using PDCCH, etc.). The user equipment 200 also controls scheduling of the synchronization signal, downlink reference signals, etc.

[0055] The PBCH is a channel for downlink communication from the base station 100 to the user equipment 200. The CH-PHY layer 123 uses the PBCH to transmit broadcast signals that the user equipment 200 needs to acquire after performing a cell search, such as system bandwidth, system frame number, and number of transmit antennas. Hereinafter, a signal block including a synchronization signal and a broadcast signal may be referred to as an SSB (Synchronization Signal Block). The user equipment 200 receives the SSB and performs timing synchronization and frequency synchronization. The user equipment 200 also identifies PRACH resources based on the received system information.

[0056] The SSB is used for a connection request from the user equipment 200 to the base station 100. Therefore, processing using the SSB is performed before a connection with the user equipment 200 is established. Since the CH-PHY layer 123 performs the processing that is performed before a connection with the user equipment 200 is established, the UH-PHY layer 124 does not need to perform processing when not connected to the user equipment 200. Therefore, the base station 100 can cut off the supply of power to the UH-PHY layer 124 that is not connected to the user equipment 200. Therefore, the base station 100 according to the embodiment can suitably suppress unnecessary power consumption due to allocation of excessive computational resources.

[0057] The PDCCH is a channel for downlink communication from the base station 100 to the user equipment 200. The CH-PHY layer 123 uses the PDCCH to transmit resource allocation information for a Downlink Shared Channel (DL-SCH), resource allocation information for a Paging Channel (PCH), Hybrid Automatic Repeat reQuest (HARQ) information for the DL-SCH, an uplink scheduling grant, and Ack / Nack, which are response signals to uplink transmissions. The amount of calculation for processing using the PDCCH does not change significantly in proportion to the number of user equipments 200. Therefore, by performing the processing using the PDCCH collectively in the CH-PHY layer 123, the amount of calculation for the entire base station 100 can be reduced.

[0058] In "Cell-Free massive MIMO," when spatially multiplexing transmission is performed for each user device 200, user data for each user device 200 is combined by precoding. Therefore, the CH-PHY layer 123 performs functions following precoding related to the PDSCH. When each UH-PHY layer 124 performs a process of combining user data for each user device 200 by precoding, there is a possibility that the processes will overlap between the UH-PHY layers 124 because the user data for each user device 200 is used. By having the CH-PHY layer 123 collectively perform the process of combining user data for each user device 200 by precoding, the overall computational load of the base station 100 can be reduced.

[0059] The UH-PHY layer 124 performs processing related to the PDSCH.

[0060] The PDSCH is a channel for downlink communication from the base station 100 to the user equipment 200. A downlink shared channel (DL-SCH) and a PCH (Paging Channel), which are transport channels, are mapped to the PDSCH. The UH-PHY layer 124 transmits user data using the PDSCH. A user operating the user equipment 200 receives various services based on the user data.

[0061] [Variation of functional division of O-DU120 during downlink communication] The base station 100 according to the embodiment does not necessarily need to divide the functions of the O-DU 120 as shown in Fig. 7. Even if the functions of the O-DU 120 are divided as shown in Fig. 8 below, the base station 100 according to the embodiment can preferably suppress unnecessary power consumption due to allocation of excessive computational resources.

[0062] Fig. 8 is a diagram showing a second example of functional division during downlink communication for the O-DU 120 according to the first embodiment. Fig. 8 differs from the example of functional division shown in Fig. 7 in that the UH-PHY layer 124 performs processing using the PDCCH. That is, the functions of the O-DU 120 may be divided so that the CH-PHY layer 123 performs processing using SSB (PSS, SSS, PBCH) and processing below precoding of the PDSCH and the UH-PHY layer 124 performs processing using the PDSCH and processing above precoding among processing using the PDCCH.

[0063] Fig. 9 is a diagram illustrating a third example of functional division during downlink communication for the O-DU 120 according to the first embodiment. Fig. 9 illustrates an example of functional division when spatial multiplexing is not performed for each user equipment 200. Fig. 9 differs from the example of functional division illustrated in Fig. 7 in that the UH-PHY layer 124 performs precoding and subsequent processing related to the PRACH. That is, the CH-PHY layer 123 may perform processing using SSB and processing using PDCCH, and the UH-PHY layer 124 may perform processing using PDSCH including precoding.

[0064] 10 is a flowchart showing an example of processing by the base station 100 according to the first embodiment. The base station 100 establishes a connection with the user equipment 200 (step S101). The base station 100 assigns the connected user equipment 200 to one of the user equipment 200 (step S102). The base station 100 does not supply power to the UH-PHY layer 124 to which the user equipment 200 has not been assigned (step S103). By not supplying power to the UH-PHY layer 124 to which the user equipment 200 has not been assigned, the base station 100 can assign appropriate computational resources according to the number of user equipment 200, thereby reducing unnecessary power consumption.

[0065] [Embodiment 2] Next, the configuration of the base station 100A according to the second embodiment will be described with reference to Fig. 11. Items that have already been described in the first embodiment may be omitted.

[0066] The base station 100 according to the first embodiment includes a CH-PHY layer 123 and a UH-PHY layer 124 in the O-DU 120. In contrast, the base station 100A according to the second embodiment includes the CH-PHY layer 123 and the UH-PHY layer 124 as nodes separate from the O-DU 120.

[0067] Fig. 11 is a diagram showing an example of functional division of a base station 100A according to the second embodiment. The base station 100A includes an O-CU 110, an O-DU 120, a first O-HU (Open-High Physical Unit) 310, and a plurality of second O-HUs 320. In Fig. 11, second O-HUs 320-1 and second O-HUs 320-2 exemplify the plurality of second O-HUs 320. Hereinafter, when there is no need to distinguish between the second O-HUs 320-1 and second O-HUs 320-2, they may be simply referred to as second O-HUs 320.

[0068] The first O-HU 310 and second O-HU 320 are provided in the base station 100A as nodes lower than the O-DU 120, and are connected to the common O-DU 120. The first O-HU 310 and second O-HU 320 are also provided in the base station 100A as nodes higher than the O-RU 130, and are connected to the common O-RU 130.

[0069] The first O-HU 310 performs the function of the CH-PHY layer 123. The second O-HU 320 performs the function of the UH-PHY layer 124. By providing the CH-PHY layer 123 and the UH-PHY layer 124 as different nodes, the base station 100 can configure the first O-HU 310 that performs the function of the CH-PHY layer 123 and the second O-HU 320 that performs the function of the UH-PHY layer 124 with devices from different manufacturers. In other words, multi-vendor support is possible. By using multi-vendor support, the base station 100A can implement a wireless communication system 10 with performance that meets the needs of the installer of the base station 100A and the user who operates the user equipment 200, at a relatively low cost.

[0070] Alternatively, the UH-PHY layers 124 may be provided in the second O-HUs 320 manufactured by different manufacturers. By providing the UH-PHY layers 124 from multiple vendors, the base station 100 can configure the second O-HUs 320 with devices having different characteristics depending on the services to be provided to the user operating the user equipment 200. Specifically, the second O-HUs 320 may have characteristics depending on the services to be provided to the user, such as a high-capacity service or a low-latency service. Furthermore, the user equipment 200 may be connected to a second O-HU 320 having characteristics depending on the services to which the user subscribes.

[0071] FIG. 12 is a block diagram showing an example of the internal configuration of a base station according to this embodiment. At least some of the functions of the base station 100 and the base station 100A can be implemented using a computer. As shown in the figure, the computer includes a central processing unit 901, a RAM 902, an input / output port 903, input / output devices 904 and 905, and a bus 906. The computer itself can be implemented using existing technology. The central processing unit 901 executes instructions contained in a program read from the RAM 902 or the like. In accordance with the instructions, the central processing unit 901 writes data to the RAM 902, reads data from the RAM 902, and performs arithmetic and logical operations. The RAM 902 stores data and programs. Each element included in the RAM 902 has an address and can be accessed using the address. RAM is an abbreviation for "random access memory." The input / output port 903 is a port through which the central processing unit 901 exchanges data with external input / output devices. The input / output devices 904 and 905 are input / output devices. Input / output devices 904 and 905 exchange data with the central processing unit 901 via an input / output port 903. A bus 906 is a common communication path used within the computer. For example, the central processing unit 901 reads and writes data from and to RAM 902 via the bus 906. Also, for example, the central processing unit 901 accesses the input / output port via the bus 906. All or part of the functional units provided in the base station 100 and base station 100A may be realized using hardware such as an ASIC, a PLD, or an FPGA. All or part of the functional units may be realized by a combination of software and hardware.

[0072] Note that all or part of the functions of each unit of base station 100 and base station 100A in the above-described embodiment may be realized by recording a program for realizing these functions on a computer-readable recording medium, and reading and executing the program recorded on the recording medium into a computer system. Note that the term "computer system" here includes hardware such as an OS and peripheral devices.

[0073] Although one embodiment of the present invention has been described in detail above with reference to the drawings, the specific configuration is not limited to the above, and various design modifications can be made without departing from the spirit of the present invention. Furthermore, the configurations described in the above-described embodiments and examples can be combined.

[0074] Furthermore, the above-described embodiment makes it possible to, for example, "optimally reduce power consumption according to the number of connected user devices," thereby contributing to Goal 9 of the United Nations-led Sustainable Development Goals (SDGs), which is to "build resilient infrastructure, promote sustainable industrialization, and foster innovation." [Explanation of symbols]

[0075] 10...Wireless communication system, 100...Base station, 110...O-CU, 111...SDAP layer, 112...RRC layer, 113...PDCP layer, 120...O-DU, 121...RLC layer, 122...MA C layer, 123...CH-PHY layer, 124...UH-PHY layer, 130...O-RU, 131...Low-PHY layer, 200...user equipment, 310...first O-HU, 320...second O-HU

Claims

1. A base station capable of communicating with a plurality of user equipment (UE) via a wireless communication system, It comprises an RLC layer (Radio Link Control layer), a MAC layer (Medium Access Control layer), and a PHY layer (Physical layer), The PHY layer comprises: a common processing unit that performs common processing for the plurality of user devices connected to the common processing unit; a plurality of user processing units that perform specific processing for each of the plurality of user devices connected to the device; Equipped with Among the plurality of user processing units, power is supplied to the user processing unit connected to the user device, and power is not supplied to the user processing unit not connected to the user device. Base station.

2. Each of the user processing units is connected to a plurality of the user devices; The maximum number of user devices simultaneously connected to each user processing unit is predetermined. The base station of claim 1 .

3. The maximum number of user devices simultaneously connected to the user processing unit varies depending on the area where the user device is installed. The base station of claim 2.

4. The common processing unit receives a signal used to establish a connection with the user equipment using a physical random access channel (PRACH) in uplink communication with the user equipment. The base station according to any one of claims 1 to 3.

5. The user processing unit receives user data of the connected user equipment using a PUSCH (Physical Uplink Shared Channel) in uplink communication with the user equipment. The base station according to any one of claims 1 to 3.

6. The common processing unit performs precoding processing before transmitting the signals transmitted from each of the user processing units to the user equipment. The base station according to any one of claims 1 to 3.

7. The common processing unit transmits a signal used for connection with the user equipment in downlink communication with the user equipment; The signal used to connect to the user device includes: a synchronization signal (Synchronization Signal: SS) transmitted from the base station to the user equipment, the synchronization signal indicating a signal detection timing; A broadcast signal transmitted using a PBCH (Physical Broadcast Channel); Contains, The base station according to any one of claims 1 to 3.

8. The user processing unit transmits user data of the connected user equipment using a PDSCH (Physical Downlink Shared Channel) in downlink communication with the user equipment. The base station according to any one of claims 1 to 3.

9. The common processing unit and each of the user processing units are provided separately and independently as a node lower than a Distributed Unit (DU) having at least a MAC layer, and a node higher than a Radio Unit (RU) in a PHY layer that controls an antenna and communicates with the user equipment. The base station according to any one of claims 1 to 3.

10. A method for controlling a base station capable of communicating with a plurality of user equipment (UE) via a wireless communication system, comprising: It comprises an RLC layer (Radio Link Control layer), a MAC layer (Medium Access Control layer), and a PHY layer (Physical layer), The PHY layer comprises: a common processing unit that performs common processing for the plurality of user devices connected to the common processing unit; a plurality of user processing units that perform specific processing for each of the plurality of user devices connected to the device; In a base station comprising: Among the plurality of user processing units, power is supplied to the user processing unit connected to the user device, and power is not supplied to the user processing unit not connected to the user device. A method for controlling a base station.

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