Wireless communication system, method for controlling wireless communication system, and distributed unit program

Abstract

The present invention comprises: a DU (21) connected to a core network (5); a plurality of radio units (RUs) connected to the DU (21); and antenna units which are connected to a respective one of the radio units and which perform wireless communication with a user terminal, wherein the DU (21) at least performs processing in the MAC layer. The RUs (311, 321) at least perform digital beamforming processing in the PHY layer and carry out coordinated beam control among the plurality of ANTs respectively connected to the RUs (311, 321). This achieves a wireless communication system capable of controlling a geographical region spread out over a relatively wide area by means of a single distributed unit provided in a single data center and executing coordinated beam control among a plurality of antenna units.

Description

Wireless communication system, wireless communication system control method, and distributed unit program

[0001] The present invention relates to wireless communication systems such as 5G networks.

[0002] 5G (fifth generation mobile communication system) has features such as high-speed communication, high reliability, low latency, and multiple simultaneous connections, and various new services that take advantage of these features have been proposed. With the aim of streamlining capital investment, 5G's entire architecture is designed with virtualization in mind. O-RAN (Open RAN) is proposed to realize vRAN (virtualized RAN), which virtualizes the Radio Access Network (RAN). In Split Option 7-2x, the CU, DU, and RU functions of the RAN are split into DU and RU, and multiple RUs are connected to one DU.

[0003] 4 shows an example of the configuration of a 5G network. As shown in the figure, the 5G network 91 includes a distributed unit (DU) 921, radio units (RUs) 9311, 9312, 9321, and 9322, a core network 95, and the like.

[0004] The DU 921, also called a slave station, mainly modulates and demodulates signals and retransmits lost signals. The DU 921 is connected to the core network 95, performs communication processing in higher layers, and is also connected to the RUs 9311, 9312, 9321, and 9322.

[0005] The RUs 9311, 9312, 9321, and 9322 are devices that perform processing of the antenna portion of the base station and the lowest layer portion of the PHY layer. The RUs 9311, 9312, 9321, and 9322 transmit and receive radio waves to and from UEs (User Equipment), and also communicate with the DU 921.

[0006] In the example shown in the figure, a DU 921 is provided in a regional data center 92 and controls communications at sites 931 and 932. In the figure, two RUs are provided at each of sites 931 and 932, but in reality, many RUs are installed at each site. A configuration in which multiple RUs are connected to a DU is disclosed in, for example, Patent Document 1.

[0007] Japan Special Table No. 2023-501314

[0008] In the above example, when one DU attempts to control communications at multiple sites spread over a relatively wide area, the distance between the DU and the RU may be, for example, several kilometers to several dozen kilometers. In this situation, when using inter-cell coordination techniques such as CoMP (Coordinated Multi-Points) or D-MIMO (Distributed-MIMO), the following issues arise with respect to fronthaul bandwidth and delay requirements.

[0009] In the commonly used Split Option 7-2x configuration, DUs are aggregated in a data center, and when performing inter-cell coordination such as D-MIMO, especially beam control using multiple cells, relatively high latency requirements must be met between cells. Because the transmission timing of each RU is controlled via a DU installed in the data center, latency occurs depending on the distance from the data center to the base station. A Split Option 8 configuration is also possible, but there are concerns that the fronthaul bandwidth will become too large as the number of antennas increases.

[0010] One aspect of the present invention aims to realize a wireless communication system that can control a relatively wide area using a single distributed unit installed in a single data center and perform coordinated beam control among multiple antenna units.

[0011] In order to solve the above problems, a wireless communication system according to the present invention includes a distributed unit connected to a core network, a plurality of wireless units connected to the distributed unit, and antenna units connected to each of the wireless units and performing wireless communication with a user terminal, wherein the distributed unit performs at least MAC layer processing, the wireless units perform at least PHY layer digital beamforming processing, and perform cooperative beam control among the plurality of antenna units connected to the wireless unit. Note that the operations of the distributed unit and the wireless units may be controlled by a RAN Intelligent Controller (RIC).

[0012] Furthermore, the control method for a wireless communication system according to the present invention is a control method for a wireless communication system including a distributed unit connected to a core network, a plurality of wireless units connected to the distributed unit, and an antenna unit connected to each of the wireless units and performing wireless communication with a user terminal, the method comprising the steps of: performing at least MAC layer processing in the distributed unit; and performing digital beamforming processing in at least the PHY layer in the wireless unit, and performing coordinated beam control among the plurality of antenna units connected to the wireless unit.

[0013] According to the present invention, it is possible to control a relatively wide area using a single distributed unit installed in a single data center, and to perform coordinated beam control among multiple antenna units.

[0014] It is a diagram showing an example of the configuration of a wireless communication system 1 according to the present embodiment. It is a diagram explaining the configuration of a fronthaul in more detail. It is a diagram showing an example of functional separation in a wireless communication architecture. It is a diagram showing an example of the configuration of a conventional 5G network.

[0015] Hereinafter, one embodiment of the present invention will be described in detail.

[0016] (Configuration example of wireless communication system) Fig. 1 shows a configuration example of a wireless communication system 1 according to this embodiment. As shown in the figure, the wireless communication system 1 includes a DU (distributed unit) 21, RUs (radio units) 311 and 321, ANTs (antenna units) 3121, 3122, 3123, 3221, 3222, 3223, and 3224, and a core network 5. Note that the wireless communication system 1 according to this embodiment is assumed to be a 5G network, but is not limited thereto, and can be applied to any wireless communication network having similar functions.

[0017] The core network 5 is a network made up of exchanges, subscriber information management devices, etc., and is used to establish user sessions and transfer user data.

[0018] The DU 21, also called a slave station, mainly performs MAC layer processing, as will be described in detail later. The DU 21 is configured by being installed on a general-purpose server serving as a regional data center 2 and virtualized. The DU 21 is connected to the core network 5, performs upper layer communication processing, and is also connected to RUs 311 and 321 provided at sites 31 and 32, respectively. In the example shown in the figure, the DU 21 controls communications at sites 31 and 32, but in reality, it may control a larger number of sites. Although not shown, the data center 2 may be provided with a RAN Intelligent Controller (RIC), which may control the operation of the DU 21 and the RUs 311 and 321.

[0019] The RUs 311 and 321 are devices that perform PHY layer processing of the base station. The RUs 311 and 321 transmit and receive radio waves to and from UEs, and also communicate with the DU 21. The RU 311 is connected to the ANTs 3121, 3122, and 3123, and the RU 321 is connected to the ANTs 3221, 3222, 3223, and 3224. In other words, the DU 21, the RUs 311 and 321, and the ANTs 3121, 3122, 3123, 3221, 3222, 3223, and 3224 form a fronthaul.

[0020] (Fronthaul Configuration) Figure 2 is a diagram illustrating in more detail the configuration of the fronthaul, i.e., the connection state of the DU21, RUs 311 and 321, and ANTs 3121, 3122, 3123, 3221, 3222, 3223, and 3224. The DU21 is connected to the RUs 311 and 321 via eCPRI (evolved Common Public Radio Interface). Furthermore, the DU21 and the RUs 311 and 321 share functions in accordance with Split Option 7-2x, which is a provision regarding the sharing of functions in the O-RAN fronthaul.

[0021] The RU 311 is connected to the ANTs 3121, 3122, and 3123 via a Common Public Radio Interface (CPRI). The RU 311 and the ANTs 3121, 3122, and 3123 share functions in accordance with Split Option 8, which is a 3GPP standard for sharing functions.

[0022] The ANTs 3121, 3122, and 3123 are each capable of 8TRx communication and transmit and receive radio waves to and from a UE (User Equipment) 6. 24TRx communication is performed between the RU 311 and the ANTs 3121, 3122, and 3123 using CPRI. As a result, 24TRx communication is also performed between the DU 21 and the RU 311 using eCPRI.

[0023] Similarly, the RU 321 is connected to the ANTs 3221, 3222, 3223, and 3224 via a Common Public Radio Interface (CPRI). The RU 321 and the ANTs 3221, 3222, 3223, and 3224 share functions in accordance with Split Option 8, which is a 3GPP standard for sharing functions.

[0024] The ANTs 3221, 3222, 3223, and 3224 are each capable of 8TRx communication and transmit and receive radio waves to and from the UE (User Equipment) 6. In this configuration example, it is assumed that the ANTs 3221, 3222, 3223, and 3224 are each configured with an antenna group, and each performs 8TRx communication using eight antennas. 32TRx communication is performed between the RU 321 and the ANTs 3221, 3222, 3223, and 3224 using CPRI. As a result, 32TRx communication is also performed between the DU 21 and the RU 321 using eCPRI.

[0025] The fronthaul configuration shown in Figure 2 is merely an example, and the number of RUs connected to a DU and the number of ANTs connected to each RU are not limited. The number of TRxs in an ANT is also not limited, and communication may be possible with a larger number of TRxs. The interface between the DU and RU, and the interface between the RU and ANT are also not limited.

[0026] (Functional Separation in Wireless Communication Architecture)

[0027] 3 shows an example of functional separation in a wireless communication architecture. In the figure, functions related to DL (Down Link) include RRC 511, PDCP 512, RLC 513, MAC High 514, MAC Low 515, Encoding 516, High PHY 517, Resource Mapping 518, Beamforming 519, IFFT 520, and RF 521. Functions related to the UL (Up Link) include RRC 611, PDCP 612, RLC 613, MAC High 614, MAC Low 615, Decoding 616, High PHY 617, Resource Demapping 618, FFT 619, and RF 620. Note that the method of separating functions is not limited to that shown in Fig. 3 and varies depending on the specifications defined by a standardization organization. However, since the contents of the basic functions are common, the example shown in Fig. 3 will be representatively described below.

[0028] RRC 511 / 611 is a Radio Resource Control protocol that controls radio resources in a wireless network. PDCP 512 / 612 is a Packet Data Convergence Protocol that is one of the sublayers in Layer 2 and is a protocol that performs confidentiality, validation, order alignment, header compression, etc. RLC 513 / 613 is a Radio Link Control protocol that is one of the sublayers in Layer 2 of the wireless interface and is a protocol that performs retransmission control, etc.

[0029] The MAC High 514 / 614 is an upper layer of the Media Access Control protocol, and performs scheduling related to wireless transmission and reception, data multiplexing and demultiplexing, etc. The MAC Low 515 / 615 is a lower layer of the Media Access Control protocol, and performs error correction processing using HARQ (Hybrid Automatic Repeat reQuest), etc.

[0030] The Encoding 516 performs FEC encoding on data received from the MAC layer in the DL, and the Decoding 616 performs decoding on data received from the PHY layer in the UL.

[0031] High PHY 517 / 617 is a layer above the physical layer, and performs processes such as scrambling and layer mapping.

[0032] The resource mapping unit 518 performs resource mapping in the DL. The resource demapping unit 618 performs resource demapping in the UL. The beamforming unit 519 performs digital beamforming processing. The IFFT unit 520 performs an inverse fast Fourier transform in the DL. The FFT unit 619 performs a fast Fourier transform in the UL. The resource mapping unit 518, the resource demapping unit 618, the beamforming unit 519, the IFFT unit 520, and the FFT unit 619 correspond to a low PHY, which is a layer below the physical layer.

[0033] The RF 518 performs DA conversion / AD conversion and transfers signals to and from an antenna that performs wireless transmission and reception.

[0034] The above-mentioned Split Option 7-2x is a provision for separating functions by a split point 74 that divides Resource Mapping 518 and Resource Demapping 618 from Beamforming 519 . That is, the functions of RRC 511 / 611, PDCP 512 / 612, RLC 513 / 613, MAC High 514 / 614, MAC Low 515 / 615, Encoding 516, Decoding 616, High PHY 517 / 617, Resource Mapping 518, and Resource Demapping 618 are provided to the CU (Central Unit) or DU, and the functions of Beamforming 519, IFFT 520, FFT 619, and RF 521 / 620 are provided to the RU.

[0035] The above-mentioned Split Option 8 is a provision for separating functions at a division point 76 that divides the IFFT 520 and FFT 619 from the RF 521 and 620 . That is, the functions of RRC 511 / 611, PDCP 512 / 612, RLC 513 / 613, MAC High 514 / 614, MAC Low 515 / 615, Encoding 516, Decoding 616, High PHY 517 / 617, Resource Mapping 518, Resource Demapping 618, Beamforming 519, IFFT 520, and FFT 619 are assigned to the CU or DU, and the functions of RF 521 / 620 are assigned to the RU.

[0036] In FIG. 3, split point 71 corresponds to Split Option 6, split point 72 corresponds to Split Option 7-3, split point 73 corresponds to Split Option 7-2, and split point 75 corresponds to Split Option 7-1.

[0037] (Transmission Bandwidth and Delay Requirements) Next, the transmission bandwidth and delay requirements will be described. For example, assuming a situation in which PDCP512 / 612 and RLC513 / 613 communications are performed at 100 MHz, 256 QAM, 32 TRx / 8 Layer, and DL: 4 Gbps / UL: 3 Gbps, in functional division between the DU and RU using Split Option 7-2x, the transmission bandwidth required between the DU and RU is 10.1 to 22.2 Gbps. On the other hand, in functional division between the DU and RU using Split Option 8, the transmission bandwidth required between the DU and RU is 157.3 Gbps for both DL and UL.

[0038] Here, when the DU and RU are functionally divided using Split Option 8, the transmission bandwidth required between the DU and RU increases, as described above. Therefore, if a large number of RUs are connected to the DU, the fronthaul bandwidth becomes too large, making it difficult to increase the number of RUs that can be connected to the DU. Therefore, it is difficult to build a system in which one DU is installed in a data center that covers a wide area.

[0039] On the other hand, when the DU and RU are functionally divided using Split Option 7-2x, as described above, the transmission bandwidth required between the DU and RU is significantly smaller than when the DU and RU are functionally divided using Split Option 8. Therefore, even in a system in which one DU is provided in a data center that has jurisdiction over a wide area, a relatively large number of RUs can be connected to the DU.

[0040] On the other hand, the delay requirement in the PHY layer is 250 μs or 200 μs, and when the DU and RU are functionally divided using Split Option 7-2x, the delay in communication between the DU and RU must be within this range. Furthermore, when performing beam control between multiple cells using inter-cell cooperation such as CoMP (Coordinated Multi-Point transmission / reception) or D-MIMO (Distributed MIMO), even stricter delay requirements must be met between cells. For example, when performing D-MIMO, when performing beam control in cooperation between RUs located in different cells, frame timing synchronization is required within a short time range of plus or minus 50 nsec.

[0041] On the other hand, because the control of the transmission timing of each RU is performed via a DU installed in a data center, delays occur according to the distance from the DU to the RU. Here, when one DU attempts to control communications in multiple cells spread over a relatively wide area, the distance between the DU and the RU may be, for example, several kilometers to several dozen kilometers. In this case, the delay time due to communications between the DU and the RU may become large, and it may not satisfy the delay requirements necessary for inter-cell coordination.

[0042] (Function Division in the Present Embodiment) In consideration of the above transmission bandwidth and delay requirements, in the present embodiment, as described above, the DU21 and the RUs 311 and 321 are functionally divided in accordance with Split Option 7-2x. Therefore, the transmission bandwidth required between the DU21 and the RUs 311 and 321 is relatively small as described above, so that even if a configuration is adopted in which a larger number of RUs are connected to the DU21, an increase in the fronthaul bandwidth can be suppressed.

[0043] Furthermore, functions are shared between RU311 and ANT3121, 3122, and 3123, and between RU321 and ANT3221, 3222, 3223, and 3224 in accordance with Split Option 8. Here, functions are shared between DU21 and RU311 and 321 in accordance with Split Option 7-2x, so RU311 and 321 have the beamforming 519 function.

[0044] That is, for example, with respect to site 31, cooperative beam control can be performed between ANTs 3121, 3122, and 3123 based on the control of RU 311. Also, since high-speed communication is possible between RU 311 and ANTs 3121, 3122, and 3123, it is possible to satisfy the delay requirements for beam control. Furthermore, the number of ANTs connected to each RU 311 is limited to those present within site 31. In other words, it is possible to suppress an increase in bandwidth within site 31. The above applies similarly to site 32. Note that the scheduling targets for DU 21 are all ANTs connected to all RUs connected to DU 21.

[0045] As described above, according to this embodiment, it is possible to provide a wireless communication network in which a relatively wide area is controlled by one DU 21 provided in one data center 2 .

[0046] (Variation of Functional Division) In the above, the DU21 and the RUs 311 and 321 share functions in accordance with Split Option 7-2x, but this is not limiting. For example, the DU21 and the RUs 311 and 321 may be functionally divided in accordance with split point 71 in FIG. 3, i.e., Split Option 6. In this case, the DU21 and the RUs 311 and 321 communicate via nFAPI (network Functional Application Platform Interface). Furthermore, the transmission bandwidth required between the DU21 and the RUs 311 and 321 is DL: 4.2 Gbps, UL: 5.6 Gbps, which allows communication with a sufficiently small bandwidth. On the other hand, when performing beam control through inter-cell cooperation such as D-MIMO, software must be built into the DU21 to link the correlation and data between different antennas.

[0047] DU21 and RU311 / 321 may be functionally divided according to split point 72 in Figure 3, i.e., Split Option 7-3. In this case, the transmission bandwidth required between DU21 and RU311 / 321 is DL: 10.1 to 22.2 Gbps, UL: 16.6 to 21.6 Gbps, and communication is possible with a sufficiently small bandwidth. On the other hand, because modulation and layer mapping depend on the RU function, it is difficult to develop software for beam control by DU21 through inter-cell coordination.

[0048] 3, i.e., Split Option 7-2. In this case, the required transmission bandwidth between the DU21 and the RUs 311 and 321 is DL: 37.8 to 86.1 Gbps, UL: 53.8 to 86.1 Gbps, which is a larger bandwidth. Furthermore, although it becomes difficult to identify the RUs in communication between the DU21 and the RUs 311 and 321, it is possible to use eCPRI.

[0049] In the above example, functions are shared between RU 311 and ANTs 3121, 3122, and 3123, and between RU 321 and ANTs 3221, 3222, 3223, and 3224, in accordance with Split Option 8, but this is not limiting. For example, functions may be split at split point 75 in FIG. 3, i.e., in accordance with Split Option 7-1. In this case, the transmission bandwidth required between the RU and the ANT is DL: 10.1 to 22.2 Gbps, UL: 53.8 to 86.1 Gbps. On the other hand, beamforming ports can be aggregated, making it easy to implement antenna coordination technology.

[0050] [Example of Implementation by Software] As described above, the DU 21 is configured by being installed on a general-purpose server and virtualized. The functions of the DU 21 (hereinafter referred to as the "device") are realized by a program that causes a computer to function as the device, and by a program that causes the computer to implement each control function of the device.

[0051] In this case, the device includes a computer having at least one control device (e.g., a processor) and at least one storage device (e.g., a memory) as hardware for executing the program. The functions described in each of the above embodiments are realized by executing the program using the control device and storage device.

[0052] The program may be non-transitory and may be recorded on one or more computer-readable recording media. The recording media may or may not be included in the device. In the latter case, the program may be supplied to the device via any wired or wireless transmission medium.

[0053] Furthermore, some or all of the functions of the control blocks can be realized by logic circuits. For example, an integrated circuit on which a logic circuit that functions as each of the control blocks is formed is also included in the scope of the present invention.

[0054] (Summary) A wireless communication system according to aspect 1 of the present invention comprises a distributed unit connected to a core network, a plurality of wireless units connected to the distributed unit, and an antenna unit connected to each of the wireless units and performing wireless communication with a user terminal, wherein the distributed unit performs at least MAC layer processing, and the wireless units perform at least digital beamforming processing in the PHY layer, and perform beam control in coordination among the plurality of antenna units connected to the wireless unit.

[0055] According to the above configuration, the transmission bandwidth required between the distributed unit and the wireless unit is relatively small, so even if a large number of wireless units are connected to the distributed unit, the increase in the fronthaul bandwidth can be suppressed. Furthermore, the bandwidth between the distributed unit and the wireless unit is relatively large, enabling high-speed communication, so the delay requirements for beam control can be met. It is possible to control a relatively wide area with a single distributed unit installed in a single data center, and to perform coordinated beam control among multiple antenna units.

[0056] A wireless communication system according to aspect 2 of the present invention may be configured in the above-described aspect 1 such that the functional division between the distributed unit and the wireless unit is performed from a division point that is the boundary between the MAC layer and the PHY layer to a division point that is the upper layer boundary of the digital beamforming processing in the PHY layer, and the functional division between the wireless unit and the antenna unit is performed from a division point that is the lower layer boundary of the digital beamforming processing in the PHY layer to a division point that is the lower layer boundary of the IFFT processing and FFT processing in the PHY layer.

[0057] According to the above configuration, the functional division of the present invention can be realized at any of the division points at which various functional divisions in wireless communication architectures have been proposed.

[0058] A wireless communication system according to aspect 3 of the present invention may be configured such that, in the above-mentioned aspect 2, the functional division between the distributed unit and the wireless unit is performed at a division point conforming to Split Option 7-2x, which is a provision regarding the division of functions in the O-RAN fronthaul, and the functional division between the wireless unit and the antenna unit is performed at a division point conforming to Split Option 8, which is a provision regarding the division of functions in 3GPP.

[0059] According to the above configuration, the transmission bandwidth required between the distributed unit and the wireless unit can be sufficiently reduced, and the communication speed between the distributed unit and the wireless unit can be sufficiently increased. This makes it easier to build a wireless communication system that can control a relatively wide area with one distributed unit installed in one data center and perform cooperative beam control among multiple antenna units.

[0060] A control method for a wireless communication system according to aspect 4 of the present invention is a control method for a wireless communication system including a distributed unit connected to a core network, a plurality of wireless units connected to the distributed unit, and antenna units connected to each of the wireless units and performing wireless communication with a user terminal, the method comprising the steps of: performing at least MAC layer processing in the distributed unit; and performing digital beamforming processing in at least the PHY layer in the wireless unit, and performing coordinated beam control among the plurality of antenna units connected to the wireless unit.

[0061] According to the above method, the transmission bandwidth required between the distributed unit and the wireless unit is relatively small, so that an increase in the fronthaul bandwidth can be suppressed even in a configuration in which a large number of wireless units are connected to the distributed unit. Furthermore, the bandwidth between the distributed unit and the wireless unit is relatively large, enabling high-speed communication, so that the delay requirements for beam control can be met. It is possible to control a relatively wide area using a single distributed unit installed in a single data center, and to perform coordinated beam control among multiple antenna units.

[0062] The distributed unit program according to aspect 5 of the present invention is a distributed unit program for causing a computer to function as a distributed unit provided in a wireless communication system according to any one of aspects 1 to 3 above, and may be configured to cause the computer to realize the functions provided by the distributed unit.

[0063] The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention.

[0064] REFERENCE SIGNS LIST 1 wireless communication system 2 data center 5 core network 21 DU (distribution unit) 31, 32 site 71, 72, 73, 74, 75, 76 division point 311, 321 RU (radio unit) 511, 611 RRC 512, 612 PDCP 513, 613 RLC 517, 617 PHY 518, 521, 620 RF 520 IFFT 619 FFT 3121, 3122, 3123, 3221, 3222, 3223, 3224 ANT (antenna unit)

Claims

1. A wireless communication system comprising: a distributed unit connected to a core network; a plurality of wireless units connected to the distributed unit; and antenna units connected to each of the wireless units and performing wireless communication with user terminals, wherein the distributed unit performs at least MAC layer processing; and the wireless units perform at least digital beamforming processing in the PHY layer and perform beam control in coordination among the plurality of antenna units connected to the wireless unit.

2. The wireless communication system according to claim 1, wherein the functional division between the distributed unit and the wireless unit is performed from a division point that is the boundary between the MAC layer and the PHY layer to a division point that is the upper layer boundary of the digital beamforming processing in the PHY layer, and the functional division between the wireless unit and the antenna unit is performed from a division point that is the lower layer boundary of the digital beamforming processing in the PHY layer to a division point that is the lower layer boundary of the IFFT processing and FFT processing in the PHY layer.

3. The wireless communication system according to claim 2, wherein the functional division between the distributed unit and the wireless unit is performed at a division point conforming to Split Option 7-2x, which is a provision regarding the division of O-RAN fronthaul functions, and the functional division between the wireless unit and the antenna unit is performed at a division point conforming to Split Option 8, which is a provision regarding the division of 3GPP functions.

4. A control method for a wireless communication system comprising a distributed unit connected to a core network, a plurality of wireless units connected to the distributed unit, and an antenna unit connected to each of the wireless units and performing wireless communication with a user terminal, the control method comprising the steps of: performing at least MAC layer processing in the distributed unit; and performing digital beamforming processing in at least the PHY layer in the wireless unit, and performing coordinated beam control among the plurality of antenna units connected to the wireless unit.

5. A distributed unit program for causing a computer to function as a distributed unit provided in a wireless communication system according to any one of claims 1 to 3, the distributed unit program causing the computer to realize the functions provided by the distributed unit.

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