Electronic device and method for providing remote interference management reference signals in fronthaul interface

Abstract

According to an embodiment, a method performed by a radio unit (RU) may include an operation of receiving a control plane (C-plane) message including segment extension information from a distributed unit (DU) over a fronthaul interface. The method may include an operation of receiving a user plane (U-plane) message including a remote interference management (RIM)-reference signal (RS) symbol from the DU over the fronthaul interface. The method may include performing operations of position adjustment of a cyclic prefix (CP) of the RIM-RS symbols and phase difference compensation of the RIM-RS symbols. The segment extension information may include at least one of indication information for indicating at least one of the RIM-RS symbols and compensation information related to phase difference compensation.

Description

Technical Field

[0001] The present disclosure relates to a fronthaul interface. More particularly, the present disclosure relates to an electronic device and method for providing a Remote Interference Management Reference Signal (RIM-RS) in a fronthaul interface. Background Art

[0002] As the transmission capacity in wireless communication systems increases, functional splitting that functionally divides the base station is being applied. According to the functional splitting, the base station can be divided into a distributed unit (DU) and a radio unit (RU). A fronthaul interface is defined for communication between the DU and the RU.

[0003] To assist in understanding the present disclosure, the above information may be provided as related art. No statement is made and no assertion is made as to whether any of the above information may be applicable as prior art related to the present disclosure. Summary of the invention

[0004] Technical Solution According to an embodiment, a method performed by a radio unit (RU) may include receiving a control plane (C-plane) message including segment extension information from a distributed unit (DU) via a fronthaul interface. The method may include receiving a user plane (U-plane) message including a remote interference management reference signal (RIM-RS) symbol from the DU via a fronthaul interface. The method may include performing phase difference compensation for the RIM-RS symbol and position adjustment of a cyclic prefix (CP) of the RIM-RS symbol. The segment extension information may include at least one indication information for indicating at least one RIM-RS symbol in the RIM-RS symbol or compensation information related to phase difference compensation.

[0005] According to an embodiment, a method performed by a distributed unit (DU) may include sending a control plane (C-plane) message including segment extension information to a radio unit (RU) via a fronthaul interface. The method may include sending a user plane (U-plane) message including a RIM-RS symbol to the RU via the fronthaul interface. The segment extension information may be used to perform phase difference compensation for the RIM-RS symbol and position adjustment of a cyclic prefix (CP) of the RIM-RS symbol. The segment extension information may include at least one indication information for indicating at least one RIM-RS symbol in the RIM-RS symbol or compensation information related to phase difference compensation.

[0006] According to an embodiment, an electronic device executed by a radio unit (RU) may include: a fronthaul transceiver, at least one radio frequency (RF) transceiver, and at least one processor coupled to the fronthaul transceiver and the at least one RF transceiver. The at least one processor may be configured to receive a control plane (C-plane) message including segment extension information from a distributed unit (DU) via a fronthaul interface. The at least one processor may be configured to receive a user plane (U-plane) message including a remote interference management reference signal (RIM-RS) symbol from the DU via a fronthaul interface. The at least one processor may be configured to perform phase difference compensation for the RIM-RS symbol and position adjustment of the cyclic prefix (CP) of the RIM-RS symbol. The segment extension information may include at least one indication information for indicating at least one RIM-RS symbol in the RIM-RS symbol or compensation information related to phase difference compensation.

[0007] According to an embodiment, an electronic device executed by a distributed unit (DU) may include: at least one transceiver including a fronthaul transceiver; and at least one processor coupled to the at least one transceiver. The at least one processor may be configured to send a control plane (C-plane) message including segment extension information to a radio unit (RU) via a fronthaul interface. The at least one processor may be configured to send a user plane (U-plane) message including a RIM-RS symbol to the RU via a fronthaul interface. The segment extension information may be used to perform phase difference compensation for the RIM-RS symbol and position adjustment of the cyclic prefix (CP) of the RIM-RS symbol. The segment extension information may include at least one indication information for indicating at least one RIM-RS symbol or compensation information related to phase difference compensation.

[0008] According to an embodiment, a non-transitory computer-readable medium is provided. The non-transitory computer-readable medium may include a memory storing a program including instructions. When the instructions are executed by a processor, a distributed unit (DU) receives a control plane (C-plane) message including segment extension information from a distributed unit (DU) via a fronthaul interface. When the instructions are executed by the processor, the DU receives a user plane (U-plane) message including a remote interference management reference signal (RIM-RS) symbol from the DU via a fronthaul interface. When the instructions are executed by the processor, the DU performs phase difference compensation for the RIM-RS symbol and position adjustment of the cyclic prefix (CP) of the RIM-RS symbol. The segment extension information may include at least one indication information for indicating at least one RIM-RS symbol in the RIM-RS symbol or compensation information related to phase difference compensation.

[0009] According to an embodiment, a non-transitory computer-readable medium is provided. The non-transitory computer-readable medium may include a memory storing a program including instructions. These instructions, when executed by a processor, cause a radio unit (RU) to send a control plane (C-plane) message including segment extension information to the RU via a fronthaul interface. The instructions, when executed by the processor, cause the RU to send a user plane (U-plane) message including RIM-RS symbols to the RU via a fronthaul interface. The segment extension information may be used to perform phase difference compensation for the RIM-RS symbol and position adjustment of the cyclic prefix (CP) of the RIM-RS symbol. The segment extension information may include at least one indication information for indicating at least one RIM-RS symbol in the RIM-RS symbol or compensation information related to phase difference compensation. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 A wireless communication system according to an embodiment is shown.

[0011] Figure 2a A fronthaul interface according to an embodiment is shown.

[0012] Figure 2b A fronthaul interface of an Open (O)-Radio Access Network (RAN) according to an embodiment is shown.

[0013] Figure 3a A functional configuration of a distributed unit (DU) according to an embodiment is shown.

[0014] Figure 3b A functional configuration of a radio unit (RU) according to an embodiment is shown.

[0015] Figure 4 An example of functional split between DU and RU according to an embodiment is shown.

[0016] Figure 5 An example of long-range interference according to an embodiment is shown.

[0017] Figure 6a , Figure 6b and Figure 6c An example of remote interference management according to an embodiment is shown.

[0018] Figure 7 An example of a Remote Interference Management (RIM)-Reference Signal (RS) structure according to an embodiment is shown.

[0019] Figure 8a An example of a functional configuration for RIM-RS transmission according to an embodiment is shown.

[0020] Figure 8b An example of RIM-RS symbol processing according to an embodiment is shown.

[0021] Fig. 9 An example of a functional configuration of each network entity for modulation compression (MC) based RIM-RS transmission according to an embodiment is shown.

[0022] Fig.10 An example of signaling for modulation compression (MC) based RIM-RS transmission between DU and RU through segment extension information of a control plane (C-plane) message according to an embodiment is shown.

[0023] Fig.11 An example of segment extension information of a C-plane message for MC-based RIM-RS transmission according to an embodiment is shown.

[0024] Fig.12 An example of signaling between DU and RU for MC-based RIM-RS transmission through C-plane messages according to an embodiment is shown.

[0025] Fig.13 An example of C-plane messages for MC-based RIM-RS transmission according to an embodiment is shown.

[0026] Fig.14 An example of signaling for MC-based RIM-RS transmission between DU and RU through user plane (U-plane) messages according to an embodiment is shown.

[0027] Fig.15 An example of U-plane messages for MC-based RIM-RS transmission according to an embodiment is shown. DETAILED DESCRIPTION

[0028] The terms used in this disclosure are only used to describe specific embodiments, rather than to limit the scope of another embodiment. Singular expressions may include plural expressions, unless the context clearly indicates otherwise. The terms used herein, including technical or scientific terms, may have the same meanings as those commonly understood by those of ordinary skill in the field described in this disclosure. Among the terms used in this disclosure, the terms defined in a general dictionary may be interpreted as having the same or similar meanings as the contextual meanings of the relevant technology, and are not interpreted as ideal or overly formal meanings, unless clearly defined in this disclosure. In some cases, even the terms defined in this disclosure may not be interpreted as excluding embodiments of the present disclosure.

[0029] In various embodiments of the present disclosure described below, a hardware method will be described as an example. However, since various embodiments of the present disclosure include techniques using both hardware and software, various embodiments of the present disclosure do not exclude software-based methods.

[0030] Terms related to signals (e.g., packets, messages, signals, information, signaling), terms related to resources (e.g., segments, symbols, time slots, subframes, radio frames, subcarriers, resource elements (REs), resource blocks (RBs), bandwidth parts (BWPs), opportunities), terms related to operating states (e.g., steps, operations, processes), terms related to data (e.g., packets, messages, user flows, information, bits, symbols, codewords), terms related to channels, terms related to network entities (e.g., distributed units (DUs), radio units (RUs), central units (CUs), CU control planes (CPs), CU user planes (UPs), open radio access network (O-RAN) DUs (O-DUs), O-RAN RUs (O-RUs), O-RAN CUs (O-CUs), O-RAN CU-CPs (O-CU-UPs), O-RAN CU-CPs (O-CU-CPs)), and terms related to components of devices used in the following description are exemplified for convenience of explanation. Therefore, the present disclosure is not limited to the terms to be described below, and another term having an equivalent technical meaning may be used. In addition, terms such as “... unit”, “... device”, “... object”, and “... structure” used below may indicate at least one shape structure, or may indicate a unit of a processing function.

[0031] In addition, in the present disclosure, the term "greater than" or "less than" can be used to determine whether a specific condition is met or complies with, but this is only a description of an expression example, and does not exclude the description of "greater than or equal to" or "less than or equal to". The condition described as "greater than or equal to" can be replaced with "greater than", the condition described as "less than or equal to" can be replaced with "less than", and the condition described as "greater than or equal to and less than" can be replaced with "greater than and less than or equal to". In addition, hereinafter, "A" to "B" refers to at least one of the elements from A (including A) to B (including B). hereinafter, "C" and / or "D" refers to at least one of "C" or "D", that is, {"C", "D" and "C" and "D"}.

[0032] Although the present disclosure uses terms used in some communication standards (e.g., 3rd Generation Partnership Project (3GPP), Scalable Radio Access Network (xRAN), Open Radio Access Network (O-RAN)) to describe various embodiments, these are only examples for illustration. Various embodiments of the present disclosure can be easily modified and applied to other communication systems. Figure 1 A wireless communication system according to an embodiment is shown.

[0033] refer to Figure 1 , Figure 1 A base station 110 and a terminal 120 are shown as a part of nodes using a wireless channel in a wireless communication system. Figure 1 Only one base station is shown, but the wireless communication system may also include additional base stations that are the same as or similar to the base station 110 .

[0034] The base station 110 is a network infrastructure that provides wireless access to the terminal 120. The base station 110 has a coverage range defined based on the distance over which a signal can be transmitted. In addition to "base station", the base station 110 may be referred to as an "access point (AP)", "eNodeB (eNB)", "fifth generation node", "next generation nodeB (gNB)", "radio point", "transmission / reception point (TRP)" or other terms with equivalent technical meanings.

[0035] The terminal 120 is a device used by a user, which performs communication with the base station 110 through a wireless channel. The link from the base station 110 to the terminal 120 is called a downlink (DL), and the link from the terminal 120 to the base station 110 is called an uplink (UL). Figure 1 Although not shown in the figure, the terminal 120 and another terminal can communicate with each other through a wireless channel. At this time, the link between the terminal 120 and another terminal (device-to-device link (D2D)) is called a side link, and the side link can be used interchangeably with the PC5 interface. In some other embodiments, the terminal 120 can operate without user participation. According to an embodiment, the terminal 120, which is a device performing machine type communication (MTC), may not be carried by the user. In addition, according to an embodiment, the terminal 120 may be a narrowband (NB) Internet of Things (IoT) device.

[0036] In addition to "terminal", terminal 120 may also be referred to as "user equipment (UE)", "customer premises equipment (CPE)", "mobile station", "user station", "remote terminal", "wireless terminal", "electronic device", "user device" or other terms with equivalent technical meanings.

[0037] The base station 110 may perform beamforming with the terminal 120. The base station 110 and the terminal 120 may transmit and receive wireless signals in a relatively low frequency band (e.g., frequency range 1 (FR1) of NR). In addition, the base station 110 and the terminal 120 may transmit and receive wireless signals in a relatively high frequency band (e.g., FR2 (or FR2-1, FR2-2, FR2-3) or FR3) and a millimeter wave band (e.g., 28 GHz, 30 GHz, 38 GHz, 60 GHz). The base station 110 and the terminal 120 may perform beamforming to improve channel gain. In this article, beamforming may include transmit beamforming and receive beamforming. The base station 110 and the terminal 120 may provide directionality to a transmitted signal or a received signal. To this end, the base station 110 and the terminal 120 may select a service beam through a beam search or a beam management process. After the service beam is selected, subsequent communication may be performed through a resource that is in a QCL relationship with a resource that transmits the service beam.

[0038] A first antenna port and a second antenna port may be evaluated to be in a QCL relationship if a large-scale characteristic of a channel carrying symbols on a first antenna port can be inferred from a channel carrying symbols on a second antenna port. For example, the large-scale characteristic may include at least one of delay spread, Doppler spread, Doppler shift, average gain, average delay, and spatial receiver parameters.

[0039] although Figure 1 It is described that both the base station 110 and the terminal 120 perform beamforming, but the embodiments of the present disclosure are not limited thereto. In some embodiments, the terminal may or may not perform beamforming. In addition, the base station may or may not perform beamforming. That is, only one of the base station and the terminal may perform beamforming, or neither the base station nor the terminal may perform beamforming.

[0040] In the present disclosure, a beam refers to a spatial stream of a signal in a wireless channel, and is formed by one or more antennas (or antenna elements), and this formation process may be referred to as beamforming. Beamforming may include at least one of analog beamforming or digital beamforming (e.g., precoding). Reference signals transmitted based on beamforming may include, for example, a demodulation reference signal (DM-RS), a channel state information reference signal (CSI-RS), a synchronization signal / physical broadcast channel (SS / PBCH), and a sounding reference signal (SRS). In addition, IEs such as CSI-RS resources or SRS-resources may be used as a configuration for each reference signal, and the configuration may include information associated with the beam. The information associated with the beam may indicate whether the corresponding configuration (e.g., CSI-RS resource) uses the same spatial domain filter as another configuration (e.g., another CSI-RS resource in the same CSI-RS resource set), or a different spatial domain filter, or which reference signal it is quasi-co-located (QCL), and if so, what type it is (e.g., QCL type A, B, C, D).

[0041] Conventionally, in a communication system in which the cell radius of a base station is relatively large, each base station is installed to include the functions of a digital processing unit (or distributed unit (DU)) and a radio frequency (RF) processing unit (or radio unit (RU)). However, as high frequency bands are used in fourth generation (4G) and / or subsequent communication systems (e.g., 5G) and the cell coverage of base stations becomes smaller, the number of base stations to cover a certain area has increased. The burden of installation costs for operators to install base stations has also increased. In order to minimize the installation cost of a base station, a structure has been proposed in which the DU and RU of a base station are separated, one or more RUs are connected to one DU through a wired network, and one or more RUs distributed geographically are deployed to cover a certain area. In the following, by Figure 2a and Figure 2b Describe the deployment structure and extension examples of base stations according to various embodiments of the present disclosure.

[0042] Figure 2a A fronthaul interface according to an embodiment is shown. Unlike the backhaul between the base station and the core network, the fronthaul refers to the part between entities between the radio access network (RAN) and the base station. Figure 2a An example of a forward transport structure between one DU 210 and one RU 220 is shown, but this is only for convenience of explanation, and the present disclosure is not limited thereto. In other words, the embodiments of the present disclosure may also be applied to the forward transport structure between one DU and multiple RUs. For example, the embodiments of the present disclosure may be applied to the forward transport structure between one DU and two RUs. In addition, the embodiments of the present disclosure may also be applied to the forward transport structure between one DU and three RUs.

[0043] refer to Figure 2a , the base station 110 may include a DU 210 and a RU 220. The fronthaul 215 between the DU 210 and the RU 220 may be operated via an Fx interface. For the operation of the fronthaul 215, an interface such as an enhanced common public radio interface (eCPRI) or a radio over Ethernet (ROE) may be used.

[0044] As communication technology develops, mobile data traffic grows, and thus the bandwidth requirements required for fronthaul between digital units and wireless units increase significantly. In deployments such as centralized / cloud radio access networks (C-RAN), the DU may be implemented to perform the functions of packet data convergence protocol (PDCP), radio link control (RLC), medium access control (MAC), and physical (PHY), and the RU may be implemented to perform the functions of the PHY layer in addition to the radio frequency (RF) functions.

[0045] DU 210 may be responsible for the upper layer functions of the wireless network. For example, DU 210 may perform the functions of the MAC layer and a portion of the PHY layer. In this document, a portion of the PHY layer is a function performed at a higher level among the functions of the PHY layer, and may include, for example, channel coding (or channel decoding), scrambling (or descrambling), modulation (or demodulation), and layer mapping (or layer demapping). According to an embodiment, if DU 210 complies with the O-RAN standard, it may be referred to as an O-RAN DU (O-DU). In an embodiment of the present disclosure, DU 210 may be replaced and represented as the first network entity of a base station (e.g., gNB) as needed.

[0046] The RU 220 may be responsible for lower layer functions of the wireless network. For example, the RU 220 may perform a portion of the PHY layer and an RF function. Here, a portion of the PHY layer is a function performed at a relatively lower level than the DU 210 among the functions of the PHY layer, and may include, for example, iFFT conversion (or FFT conversion), CP insertion (CP removal), and digital beamforming. Figure 4 , an example of such specific functional split is described in detail. RU 220 may be referred to as an access unit (AU), an access point (AP), a transmit / receive point (TRP), a remote radio head (RRH), a radio unit (RU), or other terms with equivalent technical meanings. According to an embodiment, if RU 220 complies with the O-RAN standard, it may be referred to as an O-RAN RU (O-RU). In an embodiment of the present disclosure, as needed, RU 220 may be replaced and represented as a second network entity of a base station (e.g., gNB).

[0047] although Figure 2aThe base station 110 is described as including the DU 210 and the RU 220, but the embodiments of the present disclosure are not limited thereto. The base station according to the embodiment can be implemented in a distributed deployment according to a centralized unit (CU) configured to perform functions of an upper layer of an access network (e.g., packet data convergence protocol (PDCP), radio resource control (RRC)) and a distributed unit (DU) configured to perform functions of a lower layer. At this time, the distributed unit (DU) may include Figure 1 The digital unit (DU) and the radio unit (RU) of the 5G network. Between the core (e.g., 5G core (5GC) or next generation core (NGC)) network and the radio access network (RAN), the base station can be implemented with a structure in which the CU, DU, and RU are arranged in sequence. The interface between the CU and the distributed unit (DU) can be called the F1 interface.

[0048] A centralized unit (CU) may be responsible for functions of a higher layer than a DU by being connected to one or more DUs. For example, the CU may be responsible for functions of the radio resource control (RRC) and packet data convergence protocol (PDCP) layers, and the DU and RU may be responsible for functions of lower layers. The DU may perform some functions of the radio link control (RLC), media access control (MAC), and PHY layers (high PHY), and the RU may perform the remaining functions of the PHY layer (low PHY). In addition, as an example, depending on the implementation of the distributed deployment of the base station, the digital unit (DU) may be included in the distributed unit (DU). Hereinafter, unless otherwise defined, although described as the operation of the digital unit (DU) and the RU, various embodiments of the present disclosure may be applied to a base station arrangement including a CU or an arrangement in which the DU is directly connected to the core network (i.e., the CU and the DU are integrated into a base station (e.g., an NG-RAN node) as a single entity).

[0049] Figure 2b A fronthaul interface of an open radio access network (RAN) according to an embodiment is shown. As a base station 110 according to a distributed deployment, an eNB or a gNB is illustrated.

[0050] refer to Figure 2b , the base station 110 may include an O-DU 251 and O-RUs 253-1, ... and 253-n. Hereinafter, for convenience of explanation, the operation and function of the O-RU 253-1 may be understood as a description of each other O-RU (eg, O-RU 253-n).

[0051] The O-DU 251 is composed of a Figure 4The O-DU 251 is a logical node that performs functions other than those specifically assigned to the O-RU 253-1 among the functions of a base station (e.g., eNB, gNB). The O-DU 251 may control the operations of the O-RUs 253-1, ..., and 253-n. The O-DU 251 may be referred to as a lower layer split (LLS) central unit (CU). The O-RU 253-1 is a central unit that includes a plurality of LLS components, each of which is configured to perform operations of the O-RU 253-1, ..., and 253-n. Figure 4 A logical node that performs a subset of the functions of a base station (e.g., eNB, gNB). The real-time aspects of control plane (C-plane) and user plane (U-plane) communications with the O-RU 253-1 can be controlled by the O-DU 251.

[0052] The O-DU 251 may perform communication with the O-RU 253-1 through an LLS interface. The LLS interface corresponds to a fronthaul interface. The LLS interface refers to a logical interface between the O-DU 251 and the O-RU 253-1 using a lower layer functional split (i.e., based on a functional split within the PHY). The LLS-C between the O-DU 251 and the O-RU 253-1 provides a C-plane through the LLS interface. The LLS-U between the O-DU 251 and the O-RU 253-1 provides a U-plane through the LLS interface.

[0053] exist Figure 2b In the present disclosure, the entities of the base station 110 have been described as O-DU and O-RU to describe the O-RAN. However, these names should not be construed as limiting the embodiments of the present disclosure. Figures 3a to 15 In the described embodiment, the operations of DU 210 may also be performed by O-DU 251. The description of DU 210 may also be applied to O-DU 251. Figure 3a to Figure 15 In the described embodiment, the operations of RU 220 may also be performed by O-RU 253-1. The description of RU 220 may also be applied to O-RU 253-1.

[0054] Figure 3a A functional configuration of a distributed unit (DU) according to an embodiment is shown. Figure 3a The configuration as a part of the base station illustrated in the example can be understood as Figure 2a DU 210 (or Figure 2b Hereinafter, the terms "... unit" and "... device" used below refer to a unit that processes at least one function or operation, which can be implemented by hardware or software or a combination of hardware and software.

[0055] refer to Figure 3a , the DU 210 includes a transceiver 310 , a memory 320 , and a processor 330 .

[0056] The transceiver 310 may perform functions for sending and receiving signals in a wired communication environment. The transceiver 310 may include a wired interface for controlling a direct device-to-device connection through a transmission medium (e.g., copper wire, optical fiber). For example, the transceiver 310 may send an electrical signal to another device through a copper wire, or perform conversion between an electrical signal and an optical signal. The DU 210 may communicate with a wireless unit (RU) through the transceiver 310. The DU 210 may be connected to a core network or a distributedly deployed CU through the transceiver 310.

[0057] The transceiver 310 may also perform functions for sending and receiving signals in a wireless communication environment. For example, the transceiver 310 may perform conversion functions between baseband signals and bit strings according to the physical layer specification of the system. For example, when sending data, the transceiver 310 generates complex-valued symbols by encoding and modulating the transmitted bit string. In addition, when receiving data, the transceiver 310 recovers the received bit string by demodulating and decoding the baseband signal. In addition, the transceiver 310 may include multiple transmit / receive paths. In addition, according to an embodiment, the transceiver 310 may be connected to a core network or other nodes (e.g., an integrated access backhaul (IAB)).

[0058] The transceiver 310 may send and receive signals. For example, the transceiver 310 may send a management plane (M-plane) message. For example, the transceiver 310 may send a synchronization plane (S-plane) message. For example, the transceiver 310 may send a control plane (C-plane) message. For example, the transceiver 310 may send a user plane (U-plane) message. For example, the transceiver 310 may receive a U-plane message. Figure 3a Only the transceiver 310 is shown in FIG. 2 , but according to another implementation, the DU 210 may include two or more transceivers.

[0059] As described above, the transceiver 310 transmits and receives signals. Therefore, all or some of the transceiver 310 may be referred to as a "communication unit", "transmission unit", "reception unit" or "transmission / reception unit". In addition, in the following description, transmission and reception performed through a wireless channel are used to include the meaning of performing the processing described above by the transceiver 310.

[0060] Despite Figure 3a Although not shown in the figure, the transceiver 310 may also include a backhaul transceiver for connecting to the core network or another base station. The backhaul transceiver provides an interface for performing communication with other nodes in the network. In other words, the backhaul transceiver converts a bit string sent from the base station to another node (such as another access node, another base station, an upper node, and a core network) into a physical signal, and converts a physical signal received from another node into a bit string.

[0061] The memory 320 stores basic programs, application programs, and data such as configuration information for the operation of the DU 210. The memory 320 may be referred to as a storage unit. The memory 320 may be configured with a volatile memory, a nonvolatile memory, or a combination of a volatile memory and a nonvolatile memory. In addition, the memory 320 provides stored data according to a request from the processor 330.

[0062] The processor 330 controls the overall operation of the DU 210. The processor 380 may be referred to as a control unit. For example, the processor 330 sends and receives signals through the transceiver 310 (or through the backhaul communication unit). In addition, the processor 330 writes and reads data in the memory 320. In addition, the processor 330 may perform the functions of the protocol stack required in the communication standard. Although in Figure 3a Only the processor 330 is shown in FIG. 2 , but according to another implementation, the DU 210 may include two or more processors.

[0063] Figure 3a The configuration of the DU 210 shown is only an example, and examples of DUs that implement embodiments of the present disclosure are not limited to Figure 3a In some embodiments, some configurations may be added, deleted or changed.

[0064] Figure 3b A functional configuration of a radio unit (RU) according to an embodiment is shown. Figure 3b The configuration as a part of the base station illustrated in the example can be understood as Figure 2a RU 220 or Figure 2b Configuration of O-RU 253-1. Hereinafter, the terms "... unit" and "... device" used below refer to a unit that processes at least one function or operation, which can be implemented by hardware or software or a combination of hardware and software.

[0065] refer to Figure 3b , RU 220 includes an RF transceiver 360 , a fronthaul transceiver 365 , a memory 370 , and a processor 380 .

[0066] The RF transceiver 360 performs functions for transmitting and receiving signals through a wireless channel. For example, the RF transceiver 360 up-converts a baseband signal into an RF band signal and then transmits it through an antenna, and down-converts the RF band signal received through the antenna into a baseband signal. For example, the RF transceiver 360 may include a transmission filter, a reception filter, an amplifier, a mixer, an oscillator, a DAC, and an ADC.

[0067] The RF transceiver 360 may include multiple transmit / receive paths. In addition, the RF transceiver 360 may include an antenna unit. The RF transceiver 360 may include at least one antenna array consisting of multiple antenna elements. In terms of hardware, the RF transceiver 360 may be composed of digital circuits and analog circuits (e.g., radio frequency integrated circuits (RFIC)). In this article, the digital circuits and the analog circuits may be implemented as a single package. In addition, the RF transceiver 360 may include multiple RF chains. The RF transceiver 360 may perform beamforming. In order to provide directionality to the signals to be sent and received according to the settings of the processor 380, the RF transceiver 360 may apply beamforming weights to the signals. According to an embodiment, the RF transceiver 360 may include a radio frequency (RF) block (or RF unit).

[0068] According to an embodiment, the RF transceiver 360 may send and receive signals on a wireless access network. For example, the RF transceiver 360 may send a downlink signal. The downlink signal may include a synchronization signal (SS), a reference signal (RS) (e.g., a cell-specific reference signal (CRS), a demodulation (DM)-RS), system information (e.g., MIB, SIB, remaining system information (RMSI), other system information (OSI)), a configuration message, control information, or downlink data. In addition, for example, the RF transceiver 360 may receive an uplink signal. The uplink signal may include a random access-related signal (e.g., a random access preamble (RAP)) (or message 1 (Msg1), message 3 (Msg3)), a reference signal (e.g., a sounding reference signal (SRS), DM-RS), or a power headroom report (PHR). Although in Figure 3b Only the RF transceiver 360 is shown in FIG. 2 , but according to another implementation, the RU 220 may include two or more RF transceivers.

[0069] According to an embodiment, the RF transceiver 360 may transmit a RIM-RS. The RF transceiver 360 may transmit a first type of RIM-RS (e.g., RIM-RS type 1 of 3GPP) to notify detection of remote interference. The RF transceiver 360 may transmit a second type of RIM-RS (e.g., RIM-RS type 2 of 3GPP) to notify the presence or absence of remote interference.

[0070] The fronthaul transceiver 365 may send and receive signals. According to an embodiment, the fronthaul transceiver 365 may send and receive signals on the fronthaul interface. For example, the fronthaul transceiver 365 may receive a management plane (M-plane) message. For example, the fronthaul transceiver 365 may receive a synchronization plane (S-plane) message. For example, the fronthaul transceiver 365 may receive a control plane (C-plane) message. For example, the fronthaul transceiver 365 may send a user plane (U-plane) message. For example, the fronthaul transceiver 365 may receive a U-plane message. Although Figure 3b Only the fronthaul transceiver 365 is shown in FIG. 2 , but according to another implementation, the RU 220 may include two or more fronthaul transceivers.

[0071] As described above, the RF transceiver 360 and the fronthaul transceiver 365 transmit and receive signals. Therefore, all or some of the RF transceiver 360 and the fronthaul transceiver 365 may be referred to as a "communication unit," a "transmission unit," a "reception unit," or a "transmission / reception unit." In addition, in the following description, transmission and reception performed through a wireless channel are used to include the meaning that the RF transceiver 360 performs the processing described above. In the following description, transmission and reception performed through a wireless channel are used to include the meaning that the RF transceiver 360 performs the processing described above.

[0072] The memory 370 stores basic programs, application programs, and data such as configuration information for the operation of the RU 220. The memory 370 may be referred to as a storage unit. The memory 370 may be configured with a volatile memory, a nonvolatile memory, or a combination of a volatile memory and a nonvolatile memory. In addition, the memory 370 provides the stored data according to a request from the processor 380. According to an embodiment, the memory 370 may include a memory for conditions, commands, or setting values ​​related to the SRS transmission scheme.

[0073] The processor 380 controls the overall operation of the RU 320. The processor 380 may be referred to as a control unit. For example, the processor 380 sends and receives signals through the RF transceiver 360 or the fronthaul transceiver 365. In addition, the processor 380 writes and reads data in the memory 370. In addition, the processor 380 may perform the functions of the protocol stack required by the communication standard. Although in Figure 3bOnly the processor 380 is shown in the figure, but according to another implementation, the RU 220 may include two or more processors. The processor 380, which is an instruction set or code stored in the memory 370, may be an instruction / code or a storage space storing the instruction / code at least temporarily residing in the processor 380, or a part of the circuit constituting the processor 380. In addition, the processor 380 may include various modules for performing communication. The processor 380 may control the RU 220 to perform operations according to the embodiments described later.

[0074] Figure 3b The configuration of the RU 220 shown is only an example, and examples of RUs that implement embodiments of the present disclosure are not limited to Figure 3b In some embodiments, some configurations may be added, deleted or changed.

[0075] Figure 4 An example of functional split between DU and RU according to an embodiment is shown. With the advancement of wireless communication technology, such as the introduction of the fifth generation (5G) communication system (or new radio (NR) communication system), the frequency band used has further increased. As the cell radius of the base station becomes very small, the number of RUs that need to be installed further increases. In addition, in the 5G communication system, as the amount of data transmitted has increased significantly by more than 10 times, the transmission capacity of the wired network transmitted to the fronthaul has increased significantly. Due to the above factors, the installation cost of the wired network in the 5G communication system may increase significantly. Therefore, in order to reduce the transmission capacity of the wired network and reduce the installation cost of the wired network, "functional split" can be used to reduce the transmission capacity of the fronthaul by transferring some functions of the modem of the DU to the RU.

[0076] To reduce the burden on the DU, the role of the RU, which is only responsible for existing RF functions, can be expanded to include some functions of the physical layer. As the RU performs higher-layer functions, the throughput of the RU increases, which can increase the transmission bandwidth in the fronthaul while reducing the latency requirement constraints due to response processing. On the other hand, as the RU performs higher-layer functions, the virtualization gain decreases, and the size, weight, and cost of the RU increase. Considering the trade-offs between the above advantages and disadvantages, it is necessary to achieve optimal functional splitting.

[0077] refer to Figure 4, showing the functional split in the physical layer below the MAC layer. In the case of sending a signal to a terminal via a downlink (DL) through a wireless network, the base station may sequentially perform channel coding / scrambling, modulation, layer mapping, antenna mapping, RE mapping, digital beamforming (e.g., precoding), iFFT conversion / CP insertion, and RF conversion. In the case of receiving a signal from a terminal uplink (UL) through a wireless network, the base station may sequentially perform RF conversion, FFT conversion / CP removal, digital beamforming (pre-combination), RE demapping, channel estimation, layer demapping, demodulation, decoding / descrambling. Based on the trade-offs as described above, the split of uplink functions and downlink functions may be defined in various types, as required between vendors, standard discussions, and the like.

[0078] In the first functional split 405, the first functional split in which the RU performs the RF function and the DU performs the PHY function substantially causes the PHY function to be not implemented within the RU, and may be referred to as option 8, for example. In the second functional split 410, the RU performs iFFT conversion / CP insertion in the DL of the PHY function and performs FFT conversion / CP removal in the UL, and the DU performs the remaining PHY functions. As an example, the second functional split 410 may be referred to as option 7-1. In the third functional split 420a, the RU performs iFFT conversion / CP insertion in the DL of the PHY function and performs FFT conversion / CP removal and digital beamforming in the UL, and the DU performs the remaining PHY functions. As an example, the third functional split 420a may be referred to as option 7-2x category A. In the fourth functional split 420b, the RU performs digital beamforming in both the DL and UL, and the DU performs higher PHY functions after digital beamforming. As an example, the fourth functional split 420b may be referred to as option 7-2x category B. In the fifth functional split 425, the RU performs RE mapping (or RE demapping) in both DL and UL, and the DU performs higher PHY functions after RE mapping (or RE demapping). As an example, the fifth functional split 425 can be referred to as option 7-2. In the sixth functional split 430, the RU performs up to modulation (or demodulation) in both DL and UL, and the DU performs higher PHY functions after modulation (or demodulation). As an example, the sixth functional split 430 can be referred to as option 7-3. In the seventh functional split 440, the RU performs up to encoding / scrambling (or decoding / descrambling) in both DL and UL, and the DU performs higher PHY functions after modulation (or demodulation). As an example, the seventh functional split 440 can be referred to as option 6.

[0079] According to an embodiment, in the case where a large amount of signal processing is expected, such as in the FR1 MMU, a relatively high-level functional split (e.g., the fourth functional split 420b) may be required to reduce the fronthaul capacity. In addition, in an overly high-level functional split (e.g., the sixth functional split 430), since the control interface becomes complicated and a plurality of PHY processing blocks are included in the RU, this may cause a burden on the implementation of the RU, and therefore, appropriate functional splitting may be required according to the arrangement and implementation method of the DU and the RU.

[0080] According to an embodiment, in the case where precoding of data received from the DU cannot be processed (i.e., in the case where the precoding capability of the RU is limited), the third functional split 420a or a lower functional split (e.g., the second functional split 410) may be applied. On the contrary, in the case where precoding of data received from the DU can be processed, the fourth functional split 420b or a higher functional split (e.g., the sixth functional split 430) may be applied.

[0081] Hereinafter, unless otherwise specified, the embodiments in the present disclosure are described based on the third functional split 420a (which may be referred to as Category A (CAT-A)) or the fourth functional split 420b (which may be referred to as Category B (CAT-B)) for performing beamforming processing in the RU. In the O-RAN standard, the type of O-RU is distinguished according to whether the precoding function is located at the interface of the O-DU or at the interface of the O-RU. An O-RU that does not perform precoding (i.e., low complexity) may be referred to as a CAT-A O-RU. An O-RU that performs precoding may be referred to as a CAT-B O-RU.

[0082] In the following, upper layer PHY indicates physical layer processing processed in the DU of the fronthaul interface. For example, the upper layer PHY may include FEC encoding / decoding, scrambling, modulation / demodulation. In the following, lower layer PHY indicates physical layer processing processed in the RU of the fronthaul interface. For example, the lower layer PHY may include FFT / iFFT, digital beamforming, physical random access channel (PRACH) extraction and filtering. However, the above principle does not exclude embodiments through other functional splits. The following description Figures 5 to 15 The functional configuration, signaling or operation can be applied not only to the third functional split 420a or the fourth functional split 420b, but also to other functional splits.

[0083] The embodiments of the present disclosure exemplarily describe when a DU (e.g., Figure 2a DU 210) and RU (e.g., Figure 2aWhen sending messages between RU 220 of the present invention, the eCPRI and O-RAN standards as the fronthaul interface are used. The Ethernet payload of the message may include an eCPRI header, an O-RAN header, and additional fields. In the following, the standard terms of eCPRI or O-RAN are used to describe various embodiments of the present invention, but other expressions having equivalent meanings to each term may be used as substitutes in various embodiments of the present invention.

[0084] Ethernet and eCPRI, which are easy to share with the network, can be used as the transmission protocol for fronthaul. The eCPRI header and O-RAN header can be included in the Ethernet payload. The eCPRI header can be located at the front of the Ethernet payload. The eCPRI header has the following content.

[0085] 1) ecpriVersion (4 bits): This parameter indicates the eCPRI protocol version.

[0086] 2) ecpriReserved (3 bits): This parameter is reserved for further use by eCPRI.

[0087] 3) ecpriconcatenation (1 bit): This parameter indicates when eCPRI concatenation is used.

[0088] 4) ecpriMessage (1 byte): This parameter indicates the type of service carried by the message type. For example, the parameter indicates an IQ data message, a real-time control data message, or a transport network delay measurement message.

[0089] 5) ecpriPayload (2 bytes): This parameter indicates the byte size of the payload portion of the eCPRI message.

[0090] 6) ecpriRtcid / ecpriPcid (2 bytes): This parameter is the extended antenna carrier (eAxC) identifier (eAxCID) and identifies the specific data stream associated with each of the C-plane (ecpriRtcid) or U-plane (ecpriPcid) messages.

[0091] 7) ecpriSeqid (2 bytes): This parameter provides unique message identification and sequencing at two levels. The first octet of this parameter is the sequence ID used to identify the order of messages within the eAxC message stream, and the sequence ID is used to ensure that all messages are received and to reorder out-of-order messages. The second octet of this parameter is the subsequence ID. The subsequence ID is used to verify sequencing and enable reordering when radio transmission level (eCPRI or IEEE-1914.3) fragmentation occurs.

[0092] The eAxC identifier (ID) includes a band and sector identifier “BandSector_ID”, a component carrier identifier “CC_ID”, a spatial stream identifier “RU_Port_ID”, and a distributed unit identifier “DU_Port_ID.” The bit allocation of the eAxC ID can be distinguished as follows.

[0093] 1) DU_port ID: DU_port ID is used to distinguish processing units (e.g., different baseband cards) in the O-DU. It is expected that the O-DU will allocate bits for the DU_port ID and the O-RU will append the same value to the UL U-plane messages carrying the same sectionId data.

[0094] 2) BandSector_ID: Aggregate cell identifier (the identifier of the frequency band and sector supported by the O-RU).

[0095] 3) CC_ID: CC_ID identifies the carrier component supported by the O-RU.

[0096] 4) RU_port ID: The RU_port ID specifies logical flows such as data layers or spatial streams, and logical flows such as individual parameter sets (e.g., PRACH) or signal channels (such as SRS that require specific antenna allocations).

[0097] The fronthaul application protocol may include a control plane (C-plane), a user plane (U-plane), a synchronization plane (S-plane), and a management plane (M-plane).

[0098] The control plane can be configured to provide scheduling information and beamforming information via control messages. The control plane means real-time control between the DU and the RU. The user plane may include IQ sample data transmitted between the DU and the RU. The user plane may include the user's downlink data (IQ data or SSB / RS), uplink data (IQ data or SRS / RS), or PRACH data. The weight vector of the above beamforming information can be multiplied with the user's data. The synchronization plane generally represents the service between the DU and the RU for a synchronization controller (e.g., an IEEE advanced host). The synchronization plane may be related to timing and synchronization. The management plane represents non-real-time control between the DU and the RU. The management plane may be related to initial setup, non-real-time reset or reset, and non-real-time reporting.

[0099] Messages in the control plane, i.e., C-plane messages, can be encapsulated based on a two-layer header approach. The first layer can be configured with an eCPRI common header or an IEEE 1914.3 common header, which includes fields for indicating the message type. The second layer is the application layer, which includes fields necessary for control and synchronization. In the application layer, a section defines the characteristics of U-plane data sent or received on a beam with a pattern ID. The supported section types in the C-plane are as follows.

[0100] Section Type may indicate the purpose of a control message sent in the control plane. For example, the purpose of the section type is as follows.

[0101] 1) sectionType = 0: used to indicate resource blocks or symbols that are not used in DL or UL.

[0102] 2) sectionType = 1: for most DL / UL radio channels. Here, "most" refers to channels that do not require time or frequency offsets, such as those required by hybrid parameter set channels.

[0103] 3) sectionType=2: Reserved for further use 4) sectionType = 3: PRACH and mixed parameter set channels. Channels that require time or frequency offset or are different from the nominal SCS value 5) sectionType=4: Reserved for further use 6) sectionType=5: UE scheduling information. Transmits UE scheduling information so that the RU can perform real-time BF weight calculation (O-RAN optional BF method) 7) sectionType = 6: Send UE specific channel information. Periodically send UE channel information so that the RU can perform real-time BF weight calculation (O-RAN optional BF method) 8) sectionType=7: for LAA support 9) sectionType=8: used for ACK / NACK feedback The present disclosure provides an electronic device and method for providing a Remote Interference Management (RIM) Reference Signal (RS) via a Modulation Compression (MC) technique on a fronthaul interface.

[0104] In addition, the present disclosure provides an apparatus and method for processing RIM-RS symbols in a radio unit (RU) via a management plane (M-plane) message from a distributed unit (DU) on a fronthaul interface.

[0105] In addition, the present disclosure provides an apparatus and method for processing RIM-RS symbols in a RU via a control plane (C-plane) message from a DU on a fronthaul interface.

[0106] In addition, the present disclosure provides an apparatus and method for processing RIM-RS symbols in a RU via a user plane (U-plane) message from a DU on a fronthaul interface.

[0107] In addition, the present disclosure provides an apparatus and method for processing RIM-RS symbols in a RU via segment extension information from a DU on a fronthaul interface.

[0108] An electronic device and method according to an embodiment of the present disclosure enables processing of a Remote Interference Management (RIM)-Reference Signal (RS) transmitted through a Modulation Compression (MC) technique in a Radio Unit (RU) by providing information about phase compensation on a fronthaul interface.

[0109] Effects that can be obtained from the present disclosure are not limited to the above-mentioned effects, and any other effects not mentioned herein will be clearly understood by a person of ordinary skill in the art to which the present disclosure belongs from the following description.

[0110] Figure 5 An example of long-range interference according to an embodiment is shown.

[0111] refer to Figure 5 , Figure 5 A base station 110 and a terminal 120 are shown as a part of nodes using a wireless channel in a wireless communication system.

[0112] The base station 110 is a network infrastructure that provides wireless access to the terminal 120. The base station 110 has a coverage range defined based on the distance over which a signal can be transmitted. In addition to "base station", the base station 110 may be referred to as an "access point (AP)", "eNodeB (eNB)", "fifth generation node", "next generation nodeB (gNB)", "radio point", "transmission / reception point (TRP)" or other terms with equivalent technical meanings.

[0113] The terminal 120 is a device used by a user, which performs communication with the base station 110 through a wireless channel. The link from the base station 110 to the terminal 120 is called a downlink (DL), and the link from the terminal 120 to the base station 110 is called an uplink (UL). Figure 5Although not shown in the figure, the terminal 120 and another terminal may perform communication through a wireless channel. At this time, the link (device-to-device link (D2D)) between the terminal 120 and another terminal is called a side link, and the side link may be used interchangeably with the PC5 interface. In some other embodiments, the terminal 120 may operate without user participation. According to an embodiment, the terminal 120, which is a device performing machine type communication (MTC), may not be carried by the user. In addition, according to an embodiment, the terminal 120 may be a narrowband (NB) Internet of Things (IoT) device.

[0114] In addition to "terminal", terminal 120 may also be referred to as "user equipment (UE)", "customer premises equipment (CPE)", "mobile station", "user station", "remote terminal", "wireless terminal", "electronic device", "user device" or other terms with equivalent technical meanings.

[0115] In a time division duplex (TDD) communication scheme, an uplink channel and a downlink channel may use the same frequency band. At this time, since interference between channels occurs if downlink communication and uplink communication overlap in the time domain, downlink communication and uplink communication use different time resources. The combination of time resources for TDD communication may be referred to as a TDD mode. A downlink period of a TDD mode may be set. A downlink period may be set based on at least one of one or more time slots or one or more symbols. A downlink period may be set based on one or more time slots. A downlink period may be set based on one or more symbols. A downlink period may be set based on one or more time slots and one or more symbols. In addition, an uplink period of a TDD mode may be set. An uplink period may be set based on at least one of one or more time slots or one or more symbols. An uplink period may be set based on one or more time slots. An uplink period may be set based on one or more symbols. An uplink period may be set based on one or more time slots and one or more symbols. An uplink period may be set based on one or more time slots. An uplink period may be set based on one or more symbols. An uplink period may be set based on one or more time slots and one or more symbols.

[0116] In a TDD communication system, the flexible period of the TDD mode can be operated for switching between a downlink period and an uplink period. The flexible period may also be referred to as a guard period. Typically, the flexible period is set in consideration of the propagation speed of the wireless signal and the typical path loss, but the propagation range of the wireless signal may increase under certain climatic conditions. For example, since the downlink signal 150 transmitted on the cell of the base station 130 located far away from the base station 110 is transmitted for a long time, it can be received during the uplink period of another cell, and exceeds the guard period. In this case, the downlink signal 150 may act as an interference to the uplink transmission of the terminal 120 on the cell of the base station 110. Herein, the base station 130 transmitting the downlink signal 150 may be referred to as an aggressor node. The cell of the base station 130 may be referred to as an interference source cell. The base station 110 may be referred to as a victim node. The cell of the base station 110 may be referred to as a victim cell. Interference may be referred to as long-range interference, time of flight (TOF) interference, long-distance cell interference, propagation delay interference, or self-interference. In a TDD communication system, the quality of uplink communication may deteriorate due to such long-range interference.

[0117] In the case where a downlink signal 150 of another base station 130 flows into the uplink transmission period of the base station 110, the uplink signal transmitted with a relatively low output may be easily interfered with by the downlink signal 150 (i.e., remote interference). Therefore, a method for measuring remote interference and controlling remote interference is required. In the 5G NR system, a remote interference management reference signal (RIM-RS) has been introduced to detect the above-mentioned remote interference and control the interference. In the following, Figures 6a to 6c An example of remote interference detection and interference control based on RIM-RS is described in.

[0118] Figures 6a to 6c An example of remote interference management according to an embodiment is shown. Figures 6a to 6c Architectures for remote interference handling are described. The differences between the architectures are where in the network the decision to apply interference mitigation is made, and how the decision is delivered between nodes. In the following, three architectures are illustrated, but other architecture variations can be easily considered, and artificial intelligence and machine learning can be used with the architectures.

[0119] Reference Figure 6a, the operation and management (OAM) device 610 can perform all decisions related to remote interference mitigation in a centralized remote interference management architecture. If remote interference is detected, the base station 110, which is the interfered node, can send a first type of RIM-RS (S601). The first type corresponds to the RIM-RS type 1 of 3GPP. The first type of RIM-RS can not only indicate that the cell is experiencing remote interference, but also include information about the ID of the node (or node group) sending the reference signal and the number of orthogonal frequency division multiplexing (OFDM) symbols in the affected uplink period. This information can be implicitly encoded in the RIM-RS. Since the atmospheric waveguides are interconnected, the base station 130 that provides the interference source cell that contributes to the remote interference of the interfered party can receive the RIM-RS.

[0120] Upon receiving the RIM-RS, the base station 130 as an interference source node may report the detected RIM-RS to the OAM device 610 (S602). In order to further determine how to solve the interference problem, the base station 130 may send the detected RIM-RS including the information encoded in the RIM-RS to the OAM device 610. The OAM device 610 may send a command indicating a change in the TDD mode to the base station 130 (S603). The OAM device 610 may make a decision on a suitable mitigation scheme, which requests the interference source cell to stop downlink transmission as early as possible to extend the protection period. After this, if the ducting phenomenon disappears, the base station 130 no longer detects the RIM-RS. The base station 130 may send a report on interference elimination to the OAM device 610. The OAM device 610 may command the base station 110 to stop RIM-RS transmission (S605). In addition, the OAM device 610 may request the base station 130 to restore the previous configuration of the TDD mode (S604). Operation S604 may be performed independently of operation S605.

[0121] Reference Figure 6b, if remote interference is detected, the base station 110 as the interfered node may transmit the first type of RIM-RS (S631). If the base station 130 as the interference source node receives the first type of RIM-RS, the base station 130 may identify that the base station 110 is experiencing remote interference. The base station 130 may transmit the second type of RIM-RS to the base station 110 (S633). The second type corresponds to the RIM-RS type 2 of 3GPP. The base station 130 may transmit a radio signal to the base station 110 to notify it that the first type of RIM-RS has been received and a suitable mitigation plan has been applied. The base station 110 receiving the second type of RIM-RS may detect whether there is remote interference. If the base station 110 does not detect the second type of RIM-RS, the base station 110 may identify that the remote interference disappears. The base station 110 may stop transmitting the first type of RIM-RS. After this, the base station 130 as the interference source node may restore the mode configuration before the interference detection based on the recognition that the first type of RIM-RS is no longer received.

[0122] Reference Figure 6c , if remote interference is detected, the base station 110 as the interfered node may send a first type of RIM-RS (S631). If the base station 130 as the interference source node receives the first type of RIM-RS, the base station 130 may identify that the base station 110 is experiencing remote interference. The base station 130 may send a backhaul signal to the base station 110 through the Xn interface (S633). The backhaul signal through the Xn interface may be used to notify the base station 110 of the presence or absence of the first type of RIM-RS in the base station 130. The backhaul signal indicating the absence of the first type of RIM-RS may be used to determine that the remote interference is no longer present and to stop the transmission of the first type of RIM-RS. The base station 130 as the interference source node may restore the mode configuration before the interference detection based on recognizing that the first type of RIM-RS is no longer received.

[0123] As described above, the base station may send RIM-RS to manage remote interference. The interfered node may send a first type of RIM-RS (e.g., RIM-RS type 1 of 3GPP). The first type of RIM-RS may be used to indicate the presence of remote interference in the interfered cell, that is, to notify the presence of wave pipe phenomenon. In a specific architecture (e.g., Figure 2bIn the architecture of 3GPP, the interference source node may send a second type of RIM-RS (e.g., RIM-RS type 2 of 3GPP). The second type of RIM-RS may be used to notify the presence of a wave pipe phenomenon in the interfered cell. Unlike the first type of RIM-RS, the second type of RIM-RS may not transmit additional information (e.g., the number of symbols). The description of the RIM-RS structure described below may be applied to both the first type of RIM-RS and the second type of RIM-RS.

[0124] Figure 7 An example of a remote interference management (RIM)-reference signal (RS) structure according to an embodiment is shown. RIM-RS is used to notify remote interference, and the RIM-RS structure is required to be able to detect RIM-RS without OFDM symbol synchronization between the interferer and the victim.

[0125] Reference Figure 7 , the structure of a conventional OFDM symbol may include a data symbol and a cyclic prefix (CP). Here, a conventional OFDM symbol represents a symbol used to transmit bits of other NR channels (e.g., physical downlink shared channel (PDSCH), physical downlink control channel (PDCCH), physical uplink shared channel (PUSCH), physical uplink control channel (PUCCH)) other than RIM-RS. A data symbol represents a complex symbol corresponding to a data payload and to which complex mapping has been performed. For example, a first OFDM symbol may include a CP 711 and a data symbol 712. CP 711 corresponds to one or more samples of data symbol 712. Symbol 712 refers to a complex symbol to which complex mapping has been performed. A second OFDM symbol may include a CP 721 and a data symbol 722. CP 721 corresponds to one or more samples of data symbol 722.

[0126] RIM-RS can be transmitted via two consecutive symbols. The two consecutive symbols may include a first RIM-RS symbol 731 and a second RIM-RS symbol 732. Here, the symbol represents a complex value symbol corresponding to a bit, rather than a resource length including a CP. The useful part of each symbol may be the same. The useful part represents a data payload. The data symbol of the first RIM-RS symbol 731 and the data symbol of the second RIM-RS symbol 732 may be the same. Different from the transmission structure of a general OFDM symbol, in RIM-RS, instead of the CP located at the front end of each symbol, the RIM-RS CP 733 may be located at the front of the first symbol 731 located at the front of the two symbols. The duplicate sample for the RIM-RS CP 733 is located at the end of the second symbol of the RIM-RS. Since the length of the CP is relatively long, the RIM-RS can be detected without estimating the timing of a separate OFDM symbol.

[0127] In O-RAN, various types of compression techniques can be used within each segment to improve the efficiency of data transmission between DU and RU. Compression techniques include, for example, no compression, block floating point compression (BFPC) and modulation compression (MC) techniques. The IQ data frame of the O-RAN standard may include a user data compression header (e.g., udCompHdr). The user data compression header is defined and transmitted by a bit width (e.g., 4-bit "udIqWidth") and a compression method (e.g., 4-bit "udCompMeth"). For example, the compression method may be defined as shown in the following table.

[0128] [Table 1]

[0129] Among the above compression techniques, the MC technique is a lossless method with no data loss and high compression efficiency. The MC technique relies on the property that the modulated data symbol can be represented by a very limited number of bits of the in-phase (I) component and bits of the quadrature (Q) component. For example, since the quadrature phase shift keying (QPSK) modulation symbol has only two potential states of I and two potential states of Q, the QPSK modulation symbol can be represented by a single bit of the I component and a single bit of the Q component without losing information. For another example, a symbol modulated using 64 QAM can be represented by a maximum of 3 bits of I component and 3 bits of Q component.

[0130] For the I component of the data in the U-plane message, 16 bits may be used. For the Q component of the data in the U-plane message, 16 bits may be used. That is, for data transmission in the U-plane message, 32 bits may be used. If QPSK modulation is used for modulation compression, the number of bits sent may be reduced from 32 bits to 2 bits. If 16 QAM modulation is used for modulation compression, the number of bits sent may be reduced from 32 bits to 4 bits. If 64 QAM modulation is used for modulation compression, the number of bits sent may be reduced from 32 bits to 6 bits.

[0131] In order to represent the values ​​of the I and Q components that can allow for the overlap of multiple constellation sizes that can be represented as a single word width, the constellation can be "shifted" so that the binary complement can indicate each constellation point. For example, the QPSK constellation point can be shifted by -1 / 2. The I component can be -1 or 0. The Q component can be -1 or 0. In addition, for example, the 16 QAM constellation point can be shifted by -1 / 4. The I component can be -1, -1 / 2, 0, and 1 / 2. The Q component can be -1, 1 / 2, 0, or 1 / 2. In addition, for example, the 64 QAM constellation point can be shifted by -1 / 8. The I component can be -1, -3 / 4, -1 / 2, -1 / 4, 0, 1 / 4, 1 / 2, or 3 / 4. The Q component can be -1, -3 / 4, -1 / 2, -1 / 4, 0, 1 / 4, 1 / 2, or 3 / 4.

[0132] The MC technique converts bit-level information into a shifted constellation point (SCP). The DU may send a U-plane message including the converted information to the RU according to the SCP. The DU may send a constellation shift flag (CSF) to the RU to indicate whether it is shifted. For example, "CSF" may be defined as shown in Table 2.

[0133] [Table 2]

[0134] Data compressed according to the MC technique does not indicate the actual power value. The DU may send a modulation compression scaling value (modCompScaler) to the RU so that the RU may set the power level on the modulated compressed data. The "modCompScaler" parameter refers to the scaling factor applied to the unshifted constellation points during decompression. In the O-RAN standard, the "modCompScaler" parameter may be provided to the RU through section extension information (e.g., Section Extension Type 4). The "modCompScaler" parameter may indicate the exponent component and the mantissa component by the following equation.

[0135] [Equation 1]

[0136] "mantissa" indicates the mantissa component of the indicated value. "exponent" indicates the exponent component of the indicated value. "modCompScaler[k]" indicates the k+1th bit of the "modCompScaler" parameter. For example, "modCompScaler[0]" indicates the first bit of the "modCompScaler" parameter. "modCompScaler

[14] " indicates the fifteenth bit of the "modCompScaler" parameter.

[0137] Among the 15 bits of the "modCompScaler" parameter, the most significant 4 bits indicate the exponent component, and among the 15 bits of the "modCompScaler" parameter, the least significant 11 bits indicate the mantissa component. Therefore, the value indicated by the "modCompScaler" parameter is as shown in the following equation.

[0138] [Equation 2]

[0139] "mantissa" indicates the mantissa component of the indicated value. "exponent" indicates the exponent component of the indicated value.

[0140] The Section Extension 4 of the O-RAN standard that transmits the “modCompScaler” parameter is shown in the following table.

[0141] [Table 3]

[0142] The DU may transmit the modulation compression power scaling RE mask (mcScaleReMask) to the RU. The "mcScaleReMask" parameter may indicate the location of the RE, and the same scaling and modulation type within a PRB.

[0143] The "mcScaleOffset" parameter indicates the scaling factor to be applied to the unshifted constellation points during decompression. In the O-RAN standard, the "mcScaleOffset" parameter may be provided to the RU via section extension information (e.g., Section Extension Type 4). The "mcScaleOffset" parameter may indicate the exponent component and the mantissa component via the following equation.

[0144] [Equation 3]

[0145] "mantissa" indicates the mantissa component of the indicated value. "exponent" indicates the exponent component of the indicated value. "mcScaleOffset[k]" indicates the k+1th bit of the "mcScaleOffset" parameter. For example, "mcScaleOffset[0]" indicates the first bit of the "mcScaleOffset" parameter. "mcScaleOffset

[14] " indicates the fifteenth bit of the "mcScaleOffset" parameter.

[0146] Among the 15 bits of the "mcScaleOffset" parameter, the most significant 4 bits indicate the exponent component, and among the 15 bits of the "mcScaleOffset" parameter, the least significant 11 bits indicate the mantissa component. Therefore, the value indicated by the "mcScaleOffset" parameter is as shown in the following equation.

[0147] [Equation 4]

[0148] "mantissa" indicates the mantissa component of the indicated value. "exponent" indicates the exponent component of the indicated value.

[0149] Section Extension 5 of the O-RAN standard that transmits the "mcScaleOffset" parameter is shown in the following table. Table 4 indicates one scaling value, and Table 5 indicates two scaling values.

[0150] [Table 4]

[0151] [Table 5]

[0152] The segment extension information of Tables 3 to 5 above may be included in the C-plane message. The RU may restore the desired original signal in the DU based on the compressed data received through the U-plane message and the parameters received through the C-plane message. According to an embodiment, the RU may obtain the original signal from the compressed bits based on the "csf" parameter. According to an embodiment, the RU may obtain the original signal from the compressed bits based on the "modCompScaler" parameter. According to an embodiment, the RU may obtain the original signal from the compressed bits based on the "mcscaleoffset" parameter and the "mcScaleReMask" parameter.

[0153] In the following, an embodiment of the present disclosure proposes a method for providing RIM-RS on a fronthaul interface by the above modulation compression (MC) technology. The RU may perform RIM-RS transmission according to RIM-RS bit data compressed by the MC technology based on at least some of the above parameters.

[0154] Figure 8a An example of a functional configuration for RIM-RS transmission according to an embodiment is shown. The operation of RIM-RS transmission can be implemented by a network entity. The above network entity can be a DU and an RU. At least part of the operation for RIM-RS transmission can be performed by the DU. At least another part of the operation for RIM-RS transmission can be performed by the RU.

[0155] refer to Figure 8a In operation 801, a RIM-RS sequence may be generated. The RIM-RS may be transmitted on a RIM-RS resource, which is defined by a triplet of indices in the time domain, the frequency domain, and the sequence domain. The RIM-RS sequence may be generated based on QPSK modulation of a pseudo-random sequence based on a length of 2 31 Based on this triplet, a portion of the QPSK-modulated gold sequence of length 231-1 to be used for the RIM-RS can be calculated as well as the actual position in time and frequency.

[0156] In operation 803, symbol mapping may be performed. Symbol mapping means bit alignment and complex number mapping. Complex number mapping of the RIM-RS sequence may be performed. For example, in QPSK modulation, the RIM-RS sequence may be aligned in units of two bits. The alignment unit corresponds to one symbol. Complex number mapping may include constellation mapping of bits. The I component and Q component of the constellation point indicated by the bit may be obtained.

[0157] In operation 805, the position of the CP may be adjusted. The RIM-RS may be transmitted to detect long-range interference between base stations when operating TDD in NR. Figure 7 As described, the base station can send RIM-RS through two symbols. However, unlike the general OFDM structure, in the RIM-RS structure, the RIM-RS CP is located at the front. Since the position of the CP of the RIM RS is different from the position of the CP of the general OFDM symbol, it is necessary to adjust the position of the CP when generating the RIM RS symbol. According to an embodiment, the position adjustment of the CP can be performed by a cyclic shift in the time domain. In addition, according to an embodiment, the position adjustment of the CP can be performed by phase rotating the RIM-RS symbol data in the frequency domain.

[0158] In operation 807, phase difference compensation may be performed. In addition, in the 5G NR standard, the phase of the carrier frequency is standardized and adjusted to 0 degrees to achieve channel estimation even if the terminal receives at a carrier frequency different from the carrier frequency of the base station. Since the carrier frequency f of a general NR channel is 0 The difference between the carrier frequency of the RIM-RS (eg, the reference point (f0RIM)) may require compensation for the phase difference of the starting point of the OFDM symbol. Position compensation may be performed on each of the first RIM-RS symbol and the second RIM-RS symbol.

[0159] Figure 8b An example of RIM-RS symbol processing according to an embodiment is shown. The RIM-RS symbol processing may include position adjustment of the CP and phase difference compensation of the RIM-RS symbol.

[0160] Reference Figure 8b , RIM-RS 800 may include RIM-RS CP 810, a first RIM-RS symbol 821, and a second RIM-RS symbol 823. For example, the first RIM-RS symbol 821 may include six sample groups. Each sample group may include one or more time samples. The first RIM-RS symbol 821 may include sample group #0, sample group #1, sample group #2, sample group #3, sample group #4, and sample group #5. The second RIM-RS symbol 823 may include six sample groups. The second RIM-RS symbol 823 may include sample group #0, sample group #1, sample group #2, sample group #3, sample group #4, and sample group #5. The sample group of the second RIM-RS symbol 823 may be the same as the sample group of the first RIM-RS symbol 821. The RIM-RS CP 810 may be configured to be longer than the CP length of a general OFDM symbol. For example, the RIM-RS CP 810 may include some sample groups (eg, sample groups #4 and #5) among the sample groups of the second RIM-RS symbol 823 .

[0161] According to an embodiment, RU 220 may perform position adjustment of the CP. The CP inserter for a general OFDM symbol inserts a sample group of a data symbol in front. In this document, a general OFDM symbol refers to a symbol used to transmit bits of another NR channel other than RIM-RS (e.g., a physical downlink shared channel (PDSCH), a physical downlink control channel (PDCCH), a physical uplink shared channel (PUSCH), or a physical uplink control channel (PUCCH)). However, unlike a general OFDM symbol, the RIM-RS CP 810 for the first RIM-RS symbol 821 and the second RIM-RS symbol 823 is located at the front end of the first RIM-RS symbol 821. Therefore, RU 220 may adjust the position of the CP so that two sample groups (e.g., sample group #4, sample group #5) move instead of one sample group.

[0162] According to an embodiment, RU 220 may perform phase difference compensation on each symbol. In this article, phase difference compensation refers to an operation of compensating for a phase difference caused by a difference between a carrier frequency of a general NR channel and a carrier frequency of a RIM-RS. At a first time point 830, RU 220 may perform phase difference compensation on a first RIM-RS symbol 821. At a second time point 840, RU 220 may perform phase difference compensation on a second RIM-RS symbol 822.

[0163] Fig. 9 An example of a functional configuration of each network entity for RIM-RS transmission based on modulation compression (MC) according to an embodiment is shown. The operation of RIM-RS transmission may be implemented by a network entity. The above network entities may be a DU and an RU. At least a part of the operation for RIM-RS transmission may be performed by the DU. At least another part of the operation for RIM-RS transmission may be performed by the RU. The DU illustrates Figure 2a In an embodiment, the RU 220 may include an O-DU 251. The RU 220 may include an O-DU 251. Figure 2a In an embodiment, the RU 220 may include an O-RU 253-1.

[0164] refer to Fig. 9 , operations 801, 803, and 910 may be related to the DU 210. Operations 801 and 803 may be described with reference to FIG.

[0165] In operation 801, the DU 210 may generate a RIM-RS sequence. The RIM-RS sequence may be generated based on QPSK modulation of a pseudo-random sequence. The pseudo-random sequence may be generated based on a gold sequence of length 231-1.

[0166] In operation 803, DU 210 may perform symbol mapping. DU 210 may perform symbol mapping based on the RIM-RS sequence. Symbol mapping may include constellation mapping. DU 210 may obtain an I component and a Q component of a constellation point indicated by a bit of the RIM-RS sequence.

[0167] In operation 910, DU 210 may perform MC compression. The MC compression technique is an IQ data compression technique. In the MC compression technique, DU 210 may extract bits of an I component and bits of a Q component representing a constellation to which a data symbol is mapped. That is, DU 210 may obtain bits of an I component and bits of a Q component as a result of symbol mapping. Since MC compression is performed in DU 210, data in a limited constellation mapping may be transmitted on a fronthaul.

[0168] DU 210 may send at least one parameter related to MC compression via C-plane message 915a. At least one parameter may be used for MC decompression in RU 220. For example, the at least one parameter may include a constellation shift flag (csf) to indicate whether to shift. In addition, for example, at least one parameter may include a modulation compression scaling value (modCompScaler). In addition, for example, at least one parameter may include a modulation compression power scaling RE mask (mcScaleReMask). In addition, for example, at least one parameter may include a scaling value for modulation compression (scalingmcScaleOffset). DU 210 may send C-plane message 915a to RU 220.

[0169] The DU 210 may transmit data according to the result of MC compression through the U-plane message 915b. For example, the data may include a bit indicating a modulation symbol for the RIM-RS. The DU 210 may transmit the U-plane message 915b to the RU 220.

[0170] The RU 220 may receive a C-plane message 915a from the DU 210. The RU 220 may receive a U-plane message 915b from the DU 210. Operation 803, operation 805, and operation 920 may be related to the RU 220. The description of operation 805 and operation 807 may refer to FIG. 8 .

[0171] In operation 920, RU 220 may perform MC decompression. RU 220 may perform MC decompression on the data of U-plane message 915b. For example, DU 210 may restore the bits indicating the modulation symbol for RIM-RS to the original data (e.g., 32-bit IQ sample data). RU 220 may perform MC decompression based on C-plane message 915a. After MC decompression, RU 220 may perform position adjustment and phase difference compensation of CP.

[0172] In operation 805, RU 220 may perform a position adjustment of the CP. In operation 807, RU 220 may perform a phase difference compensation. Assuming that MC compression is applied, only data in a limited constellation mapping may be transmitted. If the position adjustment of the CP and the phase difference compensation are performed after resource mapping (i.e., RE mapping) in the DU, different phase values ​​are obtained. However, it is difficult to provide a phase value in a scaled format of the current O-RAN standard (e.g., Section Extension 4 (Table 3) or Section Extension 5 (Table 4 or Table 5) of the O-RAN standard). Therefore, the CP position adjustment and the phase difference compensation according to the embodiment may be performed by RU220.

[0173] In order to process the RIM-RS in RU 220, that is, the position adjustment of the CP (e.g., operation 805) and the phase difference compensation (e.g., operation 807), it is necessary to determine whether it is the RIM-RS of the transmitted data. In addition, it is necessary to specify which network entity (e.g., DU 210 or RU 220) will calculate the phase difference as the compensation target. According to which network entity calculates the phase difference, the parameters in the message between DU 210 and RU 220 on the fronthaul interface can be newly defined. For example, DU 210 can calculate the phase difference and send a compensation value according to the calculation result to RU 220 through an M-plane message or a C-plane message. In addition, for example, DU210 can calculate the phase difference and send information about the phase difference to RU 220 through an M-plane message or a C-plane message. The calculation of the compensation value can be performed in RU 220. In addition, for example, DU 210 can send the reference point and the system center frequency of the RIM-RS to RU220 respectively through an M-plane message or a C-plane message. Thereafter, calculation of the phase difference and the compensation value may be performed in the RU 220 .

[0174] In the following, based on the above scenario, Figures 10 to 15 An embodiment of signaling between DU and RU required for processing RIM-RS is described in the following. In the embodiments described later, the C-plane message of the signaling between DU and RU may refer to Fig. 9In the embodiments described later, the U-plane message of the signaling between the DU and the RU may refer to Fig. 9 C-plane message 915b.

[0175] Fig.10 An example of signaling for MC-based RIM-RS transmission between DU and RU through segment extension information of C-plane message according to an embodiment is shown. If the bit data of RIM-RS is modulated based on MC and then the modulated symbols are sent to RU through the fronthaul interface, CP position adjustment and phase compensation are required in RU. If CP adjustment or phase difference compensation is performed in DU, RE data corresponds to different phase data values ​​and is difficult to scale using the control parameters illustrated in Tables 3 to 5. DU illustrates Figure 2a According to an embodiment, the RU 220 may include an O-DU 251. The RU 220 may include an O-DU 251. Figure 2a According to an embodiment, the RU 220 may include an O-RU 253-1.

[0176] refer to Fig.10 In operation S1001, the DU 210 may generate an M-plane message related to the RIM-RS. The M-plane message may include various parameters related to the RIM-RS. All parameters to be described later may be transmitted via the M-plane, or at least a portion of the parameters may be transmitted via the M-plane.

[0177] According to an embodiment, the M-plane message may include a parameter for indicating whether the segment extension information to be described below is supported. For example, the M-plane message may indicate a point at which the DU 210 supports the CP position adjustment of the RU 220 and the phase difference compensation of the RU 220. In addition, for example, the M-plane message may indicate a point at which the DU 210 supports the MC-based RIM-RS transmission.

[0178] According to an embodiment, the M-plane message may indicate a network entity in which calculation of the phase difference between RIM-RS transmission and a general NR channel is performed when compensating for the phase difference of the RU 220. The network entity may be the DU 210 or the RU 220. The RU 220 may identify the type of parameter for RIM-RS processing to be received from the DU 210 based on the M-plane message.

[0179] According to an embodiment, the M-plane message may include information about an in-phase / quadrature (IQ) value for phase difference compensation. Through the information about the IQ value, phase difference compensation may be performed in the RU 220 according to a fixed IQ value. In the case where the RU 220 does not perform phase difference compensation according to a fixed IQ value, the information about the IQ value may not be included in the M-plane message.

[0180] According to an embodiment, the M-plane message may include information about the difference between the RIM-RS center frequency and the center frequency of the system bandwidth, which is a compensation target. In order for RU 220 to calculate a value of phase difference compensation, DU 210 may send information about the difference between the RIM-RS center frequency and the center frequency of the system bandwidth to RU 220 through an M-plane message.

[0181] According to an embodiment, the M-plane message may include information about the RIM-RS center frequency. The DU 210 may send information about the RIM-RS center frequency through the M-plane message so that the RU 220 may calculate an IQ value for phase difference compensation. In this case, the RU 220 may obtain the center frequency of the system bandwidth through another message (e.g., C-plane) or a specified setting. The RU 220 may perform phase difference compensation based on the obtained center frequency of the system bandwidth and the RIM-RS center frequency.

[0182] According to an embodiment, the M-plane message may include information about the center frequency of the system bandwidth. The DU 210 may send information about the center frequency of the system bandwidth through the M-plane message so that the RU 220 may calculate an IQ value for phase difference compensation. In this case, the RU 220 may obtain the center frequency of the RIM-RS through another message (e.g., C-plane) or a specified setting. The RU 220 may perform phase difference compensation based on the obtained center frequency of the RIM-RS and the center frequency of the system bandwidth.

[0183] In operation S1003, the DU 210 may transmit an M-plane message to the RU 220. The RU 220 may receive the M-plane message from the DU 210. Fig.10 Transmission of an M-plane message for RIM-RS processing (eg, CP position adjustment and RIM-RS phase difference compensation) of the RU 220 is shown, but the embodiments of the present disclosure are not limited thereto. In an alternative embodiment, operations S1001 and S1003 may be omitted.

[0184] In operation S1011, the DU 210 may generate segment extension information for the RIM-RS. The segment extension information for the RIM-RS may include at least one of information about the RIM-RS symbol or information about phase difference compensation. According to an embodiment, the segment extension information about the RIM-RS may include information about the RIM-RS symbol. In addition, according to an embodiment, the segment extension information for the RIM-RS may include information about the phase difference compensation. In addition, according to an embodiment, the segment extension information for the RIM-RS may include information about the RIM-RS symbol and information about the phase difference compensation.

[0185] The information about the RIM-RS symbol according to the embodiment may indicate at least one RIM-RS symbol related to the segment extension information among the symbols used for RIM-RS transmission. In addition, for example, the information about the RIM-RS symbol may indicate whether it is a RIM-RS symbol related to the segment extension information. In addition, for example, the information about the RIM-RS symbol may indicate which symbol number it is among the symbols used for RIM-RS transmission.

[0186] The information about phase difference compensation according to the embodiment represents an IQ value applied to compensate for the phase difference, which changes due to the difference between the carrier frequency (ie, reference point) of the RIM-RS and the carrier frequency (ie, center frequency) of another NR channel other than the RIM-RS (e.g., physical downlink shared channel (PDSCH), physical downlink control channel (PDCCH), physical uplink shared channel (PUSCH), physical uplink control channel (PUCCH)). RIM-RS transmission may occupy two symbols. The phase difference may be independent depending on whether the phase difference is the first RIM-RS symbol (hereinafter referred to as the first RIM-RS symbol) or the second RIM-RS symbol (hereinafter referred to as the first RIM-RS symbol) within the two symbols.

[0187] According to an embodiment, the information about the phase difference compensation may include a compensation value for a RIM-RS symbol. For example, the information about the phase difference compensation may include a compensation value for a first RIM-RS symbol. In addition, for example, the information about the phase difference compensation may include a compensation value for a second RIM-RS symbol. In addition, for example, the information about the phase difference compensation may include a compensation value for a first RIM-RS symbol and a second RIM-RS symbol.

[0188] According to an embodiment, the information about phase difference compensation may include phase difference information of a RIM-RS symbol. For example, the information about phase difference compensation may include phase difference information of a first RIM-RS symbol (hereinafter referred to as first phase difference information). The first phase difference information may indicate the difference between a reference frequency of the first RIM-RS symbol and a carrier frequency of the current system bandwidth. In addition, for example, the information about phase difference compensation may include phase difference information of a second RIM-RS symbol (hereinafter referred to as second phase difference information). The second phase difference information may indicate the difference between a reference frequency of the second RIM-RS symbol and a carrier frequency of the current system bandwidth. In addition, for example, the information about phase difference compensation may include phase difference information of both the first RIM-RS symbol and the second RIM-RS symbol.

[0189] According to an embodiment, the information about the phase difference compensation may include a parameter for calculating a compensation value in the RU 220. For example, the information about the phase difference compensation may include information about a carrier frequency of RIM-RS transmission. In addition, for example, the information about the phase difference compensation may include information about a carrier frequency of a system bandwidth of an NR channel.

[0190] In operation S1013 , the DU 210 may transmit a C-plane message including the section extension information. The RU 220 may receive the C-plane message from the DU 210 .

[0191] In operation S1015, RU 220 may perform position adjustment and phase difference compensation for CP. RU 220 may perform position adjustment for CP. Unlike a general OFDM symbol structure, the transmission structure of RIM-RS has a long CP. In addition, the CPs of two RIM-RS symbols are set before the first RIM-RS symbol. Therefore, RU 220 may adjust the position of the CP. In the time domain, RU 220 may perform position adjustment for CP by cyclic shift of RIM-RS symbols. In the frequency domain, RU 220 may perform position adjustment for CP by phase rotation of RIM-RS symbols. For example, in order to implement the CP of RIM-RS by a CP inserter for a general OFDM symbol structure, RU 220 may perform cyclic shift or phase rotation by the length of some sample groups of RIM-RS symbols.

[0192] RU 220 may perform phase difference compensation. RU 220 may perform phase difference compensation on a RIM-RS symbol. RU 220 may perform phase difference compensation on each of two symbols used for RIM-RS transmission. RU 220 may perform phase difference compensation on each RIM-RS symbol.

[0193] Fig.10 Only the M-plane message and the C-plane message are shown, but before performing the position adjustment of the CP and the phase difference compensation for the RIM-RS, the RU 220 may receive the U-plane message from the DU 210. The RU 220 may receive the IQ compression information of the RIM-RS modulated by the MC compression technology from the DU 210 through the U-plane message. The RU 220 may perform decompression on the IQ compression information based on the C-plane message. For example, the RU 220 may perform decompression based on the parameters of Tables 3 to 5 above. The RU 220 may identify the IQ data of the RIM-RS.

[0194] exist Fig.10In the embodiment of receiving a C-plane message including segment extension information of the RIM-RS after receiving an M-plane message related to the RIM-RS, an embodiment has been described, but the embodiments of the present disclosure are not limited thereto. The RU 220 may perform RIM-RS processing based on at least one of the M-plane message and the C-plane message. At least a portion of the parameters for position adjustment of the CP and phase difference compensation of the RIM-RS may be sent through the C-plane message. At least another portion of the parameters may be sent through the M-plane message. On the other hand, if all parameters for position adjustment of the CP and phase difference compensation of the RIM-RS are sent through the C-plane message, the M-plane message may be omitted. According to an embodiment, operations S1001 and S1003 may be omitted. The RU 220 may perform position adjustment of the CP and phase difference compensation for the RIM-RS based on the C-plane message.

[0195] Despite Fig.10 Although not shown in the figure, according to an embodiment, RU 220 may send capability information about whether new segment extension information is supported (i.e., MC-based RIM-RS transmission, or CP position adjustment in RU and phase difference compensation of RIM-RS) to DU 210. In addition, according to an embodiment, RU 220 may send capability information to DU 210, which notifies that calculation of the phase difference between RIM-RS transmission and a general NR channel is possible. In addition to the above-mentioned embodiments, in addition to the above-mentioned M-plane message, signaling for negotiating and sending required M-plane parameters may be performed on the fronthaul interface between DU and RU.

[0196] Fig.11 An example of segment extension information of a C-plane message for MC-based RIM-RS transmission according to an embodiment is shown. For RIM-RS processing in RU, a new extension segment can be defined. DU can send a C-plane message including segment extension information for MC-based RIM-RS transmission to RU. Fig.11 The C-plane message including the section extension information shown may be in Fig.10 The segment extension information generated in operation S1011.

[0197] The segment extension information for MC-based RIM-RS transmission according to an embodiment may be used with a segment of a C-plane message of a specified type. According to an embodiment, the segment type of the C-plane message may be "1". According to an embodiment, the segment type of the C-plane message may be "3". According to an embodiment, the segment type of the C-plane message may be "5".

[0198] Reference Fig.11According to an embodiment, the segment extension information 1110 may include RIM-RS symbol indication information. For example, the segment extension information 1110 may consist of 4 octets. The segment extension information 1110 may include "extType" providing the extension type. The segment extension information 1110 may include "ef" indicating whether there is another extension or whether the current extension field is the last extension. The segment extension information 1110 may include "extLen" providing the length of the segment extension in units of 32-bit (or 4-byte) words.

[0199] The RIM-RS symbol indication information "rimrsSymbolInd" of the segment extension information 1110 may indicate a RIM-RS symbol associated with the corresponding segment and the segment extension information 1110. Two symbols may be required for RIM-RS transmission. The RIM-RS symbol indication information may indicate at least one of the two symbols. For example, the RIM-RS symbol indication information may indicate a first RIM-RS symbol (hereinafter referred to as the first RIM-RS symbol) among the two symbols. For another example, the RIM-RS symbol indication information may indicate a second RIM-RS (hereinafter referred to as the second RIM-RS symbol) among the two symbols. For another example, the RIM-RS symbol indication information may indicate each of the two symbols, namely the first RIM-RS symbol and the second RIM-RS symbol. For example, the RIM-RS symbol indication information may consist of one octet, namely 8 bits. For example, in the case where the value of the bit having the octet indicates 1, the RIM-RS symbol indication information may indicate the first RIM-RS symbol. For example, in the case where the value of the bit having the octet indicates 2, the RIM-RS symbol indication information may indicate the second RIM-RS symbol. For example, in the case where the value of the bit having the octet indicates 3, the RIM-RS symbol indication information may indicate the first RIM-RS symbol and the second RIM-RS symbol. Fig.11 An 8-bit octet is illustrated in FIG. 1 , but the embodiments of the present disclosure are not limited thereto. In another embodiment, less than 8 bits may be used to indicate a RIM-RS symbol.

[0200] Unlike the segment extension information 1120, the segment extension information 1130, and the segment extension information 1140 described below, the segment extension information 1110 may include only the RIM-RS symbol indication information. The DU 210 may send only the RIM-RS symbol indication information to the RU 220, without the phase difference compensation information in the segment extension information. According to an embodiment, the RU 220 may perform the phase difference compensation based on a fixed IQ value. According to another embodiment, the RU 220 may perform the phase difference compensation based on the IQ value sent through the C-plane message or the M-plane message before the segment extension information 1110. According to yet another embodiment, the RU 220 may perform the phase difference compensation based on the IQ value calculated based on the parameters (e.g., center frequency, phase difference information) sent through the C-plane message or the M-plane message before the segment extension information 1110.

[0201] According to an embodiment, the segment extension information 1120 may include RIM-RS symbol indication information, phase difference compensation information of the first RIM-RS symbol (hereinafter referred to as the first phase difference compensation information), and phase difference compensation information of the second RIM-RS symbol (hereinafter referred to as the second phase difference compensation information). For example, the segment extension information 1120 may consist of 12 octets. The segment extension information 1120 may include "extType" that provides the extension type. The segment extension information 1120 may include "ef" that indicates whether there is another extension or whether the current extension field is the last extension. The segment extension information 1120 may include "extLen" that provides the length of the segment extension in units of 32-bit (or 4-byte) words.

[0202] The RIM-RS symbol indication information 'rimrsSymbolInd' of the segment extension information 1120 may indicate a RIM-RS symbol related to the corresponding segment and the segment extension information 1120. For the segment extension information 1120, the description of the RIM-RS symbol indication information of the segment extension information 1110 may be applied in the same manner.

[0203] The first phase difference compensation information "phaseDecompIq_0" of the segment extension information 1120 may indicate the phase difference compensation information of the first RIM-RS symbol. The first phase difference compensation information may include an IQ value for compensating the phase of the first RIM-RS symbol. The compensation target may be the difference between the carrier frequency (e.g., reference point f0RIM) of the first RIM-RS symbol and the carrier frequency f0 of the general NR channel. The second phase difference compensation information "phaseDecompIq_1" of the segment extension information 1120 may indicate the phase difference compensation information of the second RIM-RS symbol. The second phase difference compensation information may include an IQ value for compensating the phase of the second RIM-RS symbol. The compensation target may be the difference between the carrier frequency (e.g., reference point f0RIM) of the second RIM-RS symbol and the carrier frequency f0 of the general NR channel.

[0204] According to an embodiment, the segment extension information 1130 may include RIM-RS symbol indication information and phase difference compensation information. For example, the segment extension information 1130 may consist of 8 octets. The segment extension information 1130 may include "extType" providing the extension type. The segment extension information 1130 may include "ef" indicating whether there is another extension or whether the current extension field is the last extension. The segment extension information 1130 may include "extLen" providing the length of the segment extension in units of 32-bit (or 4-byte) words.

[0205] The RIM-RS symbol indication information 'rimrsSymbolInd' of the sector extension information 1130 may indicate a RIM-RS symbol related to the corresponding sector and the sector extension information 1130. For the sector extension information 1130, the description of the RIM-RS symbol indication information of the sector extension information 1110 may be applied in the same manner.

[0206] The "phaseDecompIq" of the phase difference compensation information of the segment extension information 1130 may include an IQ value for compensating the phase of the RIM-RS symbol. In this article, the RIM-RS symbol may be indicated by the RIM-RS symbol indication information. That is, the phase difference compensation information of the segment extension information 1130 may include an IQ value for compensating the phase of the RIM-RS symbol indicated by the RIM-RS symbol indication information. For example, in the case where the RIM-RS symbol indication information indicates the first RIM-RS symbol, the IQ value of the phase difference information may be used to compensate the first RIM-RS symbol. In addition, for example, in the case where the RIM-RS symbol indication information indicates the second RIM-RS symbol, the IQ value of the phase difference information may be used to compensate the second RIM-RS symbol. In addition, for example, in the case where the RIM-RS symbol indication information indicates both the first RIM-RS symbol and the second RIM-RS symbol, the IQ value of the phase difference information may be used to compensate both the first RIM-RS symbol and the second RIM-RS symbol. For example, the phase difference compensation information may consist of four octets, i.e., 32 bits. As an example, 32 bits may indicate an IQ value used to compensate for the phase of a RIM-RS symbol.

[0207] According to an embodiment, the segment extension information 1140 may include RIM-RS symbol indication information and phase difference information. For example, the segment extension information 1140 may consist of 8 octets. The segment extension information 1140 may include "extType" providing the extension type. The segment extension information 1140 may include "ef" indicating whether there is another extension or whether the current extension field is the last extension. The segment extension information 1120 may include "extLen" providing the length of the segment extension in units of 32-bit (or 4-byte) words.

[0208] The RIM-RS symbol indication information 'rimrsSymbolInd' of the sector extension information 1140 may indicate a RIM-RS symbol related to the corresponding sector and the sector extension information 1140. For the sector extension information 1140, the description of the RIM-RS symbol indication information of the sector extension information 1110 may be applied in the same manner.

[0209] The phase difference information "phaseDifference" of the segment extension information 1140 indicates the difference between the frequency of the RIM-RS and the carrier frequency of the system bandwidth. In the frequency domain, the difference between the frequencies may correspond to the phase difference. The RU 220 may calculate an IQ value for compensation based on the phase difference information. For example, the phase difference information may consist of four octets, i.e., 32 bits. As an example, 32 bits may indicate the difference between the center frequency of the RIM-RS and the center frequency of the system bandwidth in a specified unit (e.g., 100 kilohertz (kHz), 10 kHz).

[0210] RU 220 may perform compensation for the RIM-RS symbol based on the calculated IQ value. For example, when the RIM-RS symbol indication information indicates the first RIM-RS symbol, the calculated IQ value may be used to compensate the first RIM-RS symbol. In addition, for example, when the RIM-RS symbol indication information indicates the second RIM-RS symbol, the calculated IQ value may be used to compensate the first RIM-RS symbol.

[0211] Although the phase difference information "phaseDifference" of the segment extension information 1140 is described, a method of transmitting a parameter for determining the phase difference to the RU 220 may be operated instead of directly transmitting the phase difference information to the RU 220. According to an embodiment, the segment extension information 1140 may include frequency information (e.g., "rimCenterFreq") indicating the center frequency of the RIM-RS instead of the phase difference information. For example, the frequency information may indicate the center frequency of the RIM-RS in 4 octets (i.e., 32 bits). The frequency information may indicate the absolute radio frequency channel number (ARFCN) of the center frequency of the RIM-RS.

[0212] Fig.12 An example of signaling for MC-based RIM-RS transmission between DU and RU through C-plane messages according to an embodiment is shown. Fig.10 different, Fig.12 A method for controlling RIM-RS processing of a RU based on IEs in C-plane messages or fields in C-plane messages instead of segment extension information is described. Figure 2a In an embodiment, the RU 220 may include an O-DU 251. The RU 220 may include an O-DU 251. Figure 2a RU 220. In an embodiment, RU 220 may include O-RU 253-1.

[0213] refer to Fig.12, in operation S1201, DU 210 may generate an M-plane message related to RIM-RS. According to an embodiment, the M-plane message may include a parameter for indicating whether the information including the IE for RIM-RS in the C-plane message described below is supported. In an embodiment, the M-plane message may indicate which network entity performs the calculation of the phase difference between the RIM-RS transmission and the general NR channel when compensating the phase difference of RU 220. In an embodiment, the M-plane message may include information about the IQ value used for phase difference compensation. According to an embodiment, the M-plane message may include information about the difference between the RIM-RS center frequency and the center frequency of the system bandwidth, which difference is the compensation target. According to an embodiment, the M-plane message may include information about the RIM-RS center frequency. According to an embodiment, the M-plane message may include information about the center frequency of the system bandwidth. All parameters in the above-mentioned M-plane message may be transmitted through the M-plane, or at least a part of the parameters may be transmitted through the M-plane. A detailed description of each parameter may refer to Fig.10 .

[0214] In operation S1203, the DU 210 may transmit an M-plane message to the RU 220. The RU 220 may receive the M-plane message from the DU 210. The RU 220 may receive the M-plane message from the DU 210. Fig.12 Transmission of an M-plane message for RIM-RS processing (eg, CP position adjustment and RIM-RS phase difference compensation) of the RU 220 is shown, but the embodiments of the present disclosure are not limited thereto. In an alternative embodiment, operations S1201 and S1203 may be omitted.

[0215] In operation S1211, DU 210 may generate a C-plane message including an IE for RIM-RS. The IE for RIM-RS may include at least one of information for RIM-RS symbols or information for phase difference compensation. According to an embodiment, the "reserved" field of the existing C-plane message may be replaced with at least one of information about RIM-RS symbols or information about phase difference compensation. In addition, according to an embodiment, the IE of the existing C-plane message may be replaced with at least one of information about RIM-RS symbols or information about phase difference compensation. In addition, according to an embodiment, at least one of information about RIM-RS symbols or information about phase difference compensation may be added to the C-plane message. The information about RIM-RS symbols may refer to information about Fig.10 Description of information about RIM-RS symbols in . Information about phase difference compensation may refer to information about Fig.10 Description of the information of phase difference compensation.

[0216] In operation S1213 , the DU 210 may transmit a C-plane message. The RU 220 may receive the C-plane message from the DU 210 .

[0217] In operation S1215, the RU 220 may perform position adjustment and phase difference compensation for the CP. The RU 220 may perform position adjustment for the CP. In the time domain, the RU 220 may perform position adjustment for the CP by cyclic shift of the RIM-RS symbol. In the frequency domain, the RU 220 may perform position adjustment for the CP by phase rotation of the RIM-RS symbol. The RU 220 may perform phase difference compensation. The RU 220 may perform phase difference compensation for the RIM-RS symbol. The RU 220 may perform phase difference compensation for each of the two symbols used for RIM-RS transmission. The RU 220 may perform phase difference compensation for each RIM-RS symbol.

[0218] exist Fig.12 In FIG. 2 , only the M-plane message and the C-plane message are shown, but before performing the position adjustment of the CP and the phase difference compensation operation for the RIM-RS, the RU 220 may receive the U-plane message from the DU 210. The RU 220 may receive the IQ compression information of the RIM-RS modulated by the MC compression technology through the U-plane message from the DU 210. The RU 220 may perform decompression on the IQ compression information based on the C-plane message. For example, the RU 220 may perform decompression based on the parameters of Tables 3 to 5 above. The RU 220 may identify the IQ data of the RIM-RS.

[0219] exist Fig.12 In the embodiment of receiving a C-plane message including an IE for RIM-RS after receiving an M-plane message related to RIM-RS, the embodiment of the present disclosure is described, but the embodiments of the present disclosure are not limited thereto. If all parameters for position adjustment of CP and phase difference compensation of RIM-RS are sent through the C-plane message, the M-plane message may be omitted. According to the embodiment, operation S1201 and operation S1203 may be omitted.

[0220] Despite Fig.12Although not shown in the figure, according to an embodiment, the RU 220 may send capability information about whether information including an IE for RIM-RS in a new C-plane message is supported (i.e., MC-based RIM-RS transmission, or CP position adjustment in the RU and phase difference compensation of RIM-RS) to the DU 210. In addition, according to an embodiment, the RU 220 may send capability information indicating that calculation of the phase difference between RIM-RS transmission and a general NR channel is possible to the DU 210. In addition to the above-mentioned embodiments, in addition to the above-mentioned M-plane message, signaling for negotiating and transmitting required M-plane parameters may be performed on the fronthaul interface between the DU and the RU.

[0221] Fig.13 An example of a C-plane message for MC-based RIM-RS transmission according to an embodiment is shown. For RIM-RS processing in the RU, a C-plane information element (IE) or a "reserved" field may be used. The DU may send a C-plane message including an IE for MC-based RIM-RS transmission to the RU. Fig.13 The C-plane message illustrated in the example may be in Fig.12 The C-plane message generated in operation S1211.

[0222] The information for MC-based RIM-RS transmission according to an embodiment may be used with a segment of a C-plane message of a specified type. According to an embodiment, the segment type of the C-plane message may be "1". According to an embodiment, the segment type of the C-plane message may be "3". According to an embodiment, the segment type of the C-plane message may be "5".

[0223] Reference Fig.13 , C-plane message 1310 may include multiple fields. The segment type of C-plane message 1310 may be "1". C-plane message 1320 may include multiple fields. The segment type of C-plane message 1320 may be "3". Fig.13 2 , segment type 1 or segment type 3 is illustrated in FIG. 1 , but as described above, the description of the embodiments described later can be equally applied to other segment types (eg, segment type 5).

[0224] The C-plane message 1310 of segment type 1 or the C-plane message 1320 of segment type 3 may include a "reserved" field according to the current standard. According to some embodiments, instead of the "reserved" field of the C-plane message 1310 or the C-plane message 1320, an IE for RIM-RS may be placed. Instead of the "reserved" field of the C-plane message 1310 or the C-plane message 1320, RIM-RS symbol indication information may be included. "rimrsSymbolInd" of the RIM-RS symbol indication information may indicate a RIM-RS symbol related to the segment of the corresponding C-plane message. Two symbols may be required for RIM-RS transmission. The RIM-RS symbol indication information may indicate at least one of the two symbols. For example, the RIM-RS symbol indication information may indicate a first RIM-RS symbol (hereinafter referred to as the first RIM-RS symbol) among the two symbols. For another example, the RIM-RS symbol indication information may indicate a second RIM-RS (hereinafter referred to as the second RIM-RS symbol) among the two symbols. For the RIM-RS symbol identification information, reference may be made to Fig.11 Description.

[0225] According to some embodiments, DU 210 may indicate RIM-RS symbol indication information based on an existing IE instead of the "reserved" field of a C-plane message. Bits compressed by modulation compression technology may be sent to a fronthaul interface. Here, compression and allocation may be performed in units of symbols by modulation compression technology. Therefore, the IE used to indicate the RIM-RS symbol needs to have a relatively low impact on the existing symbols. According to an embodiment, an IE with a low probability of conflict with RIM-RS and another general NR channel (e.g., PDCCH, PDSCH, PUCCH, PUSCH) may be used to indicate the RIM-RS symbol. According to an embodiment, the RIM-RS symbol indication information may be indicated based on the "filterIndex" of the IE located in the header of the C-plane message. The "filterIndex" IE information in the current standard is as follows.

[0226] [Table 6]

[0227] According to an embodiment, some values ​​indicating "reserved" in Table 6 may be used to indicate a RIM-RS symbol. For example, referring to Table 7 below, some values ​​of 'filterIndex' IE may indicate a RIM-RS symbol.

[0228] [Table 7]

[0229] According to some embodiments, DU 210 may add a newly defined octet to the C-plane message. Fig.11 The extra bytes described in the parameters are added to the C-plane message.

[0230] According to an embodiment, the C-plane message 1310 may include an octet, i.e., an 8-bit field, including RIM-RS symbol indication information "rimrsSymbolInd" as a new parameter. The RIM-RS symbol indication information may indicate a specific RIM-RS symbol among two symbols of the RIM-RS transmission corresponding to the segment of the C-plane message 1310. Fig.13 Only the RIM-RS symbol indication information "rimrsSymbolInd" is shown, but other parameters may also be added. For example, a field including the phase difference compensation information "phaseDecompIq" (or at least one of the first phase difference compensation information "phaseDecompIq_0" or the second phase difference compensation information "phaseDecompIq_1") may be added to the C-plane message. In addition, for example, a field including the phase difference information "phaseDifference" may be added to the C-plane message. In addition, for example, a field including the frequency information "rimCenterFreq" indicating the center frequency of the RIM-RS may be added to the C-plane message. The specific description of each parameter is as follows.

[0231] -RIM-RS symbol indication information "rimrsSymbolInd" may indicate a RIM-RS symbol associated with a corresponding segment of a C-plane message. RIM-RS transmission may require two symbols. For example, the RIM-RS symbol indication information may consist of one octet, i.e., 8 bits. The 8 bits may indicate at least one of the first RIM-RS symbol or the second RIM-RS symbol among the two symbols of the RIM-RS transmission.

[0232] -The phase difference compensation information "phaseDecompIq" may include an IQ value for compensating the phase of the RIM-RS symbol. In this article, the RIM-RS symbol may be indicated by the RIM-RS symbol indication information. For example, the phase difference compensation information may consist of 4 octets, i.e., 32 bits. As an example, 32 bits may indicate an IQ value for compensating the phase of the RIM-RS symbol. According to another embodiment, instead of the phase difference compensation information "phaseDecompIq", the first phase difference compensation information "phaseDecompIq_0" and the second phase difference compensation information "phaseDecompIq_1" may be used.

[0233] -The phase difference information "phaseDifference" indicates the difference between the frequency of the RIM-RS and the carrier frequency of the system bandwidth. For example, the phase difference information may consist of 4 octets, i.e., 32 bits. As an example, 32 bits may indicate the difference between the center frequency of the RIM-RS and the center frequency of the system bandwidth in a specified unit (e.g., 100 kHz, 10 kHz).

[0234] - The frequency information (eg, "rimCenterFreq") may indicate the center frequency of the RIM-RS. For example, the frequency information may indicate the center frequency of the RIM-RS in 4 octets (ie, 32 bits). The frequency information may indicate the absolute radio frequency channel number (ARFCN) of the center frequency of the RIM-RS.

[0235] For compatibility, the above parameters may be optionally included in the C-plane message. Optional parameters may be activated based on the parameters defined in the M-plane. In addition, unlike the RIM-RS symbol indication information, other parameters may be omitted in some sections. Fig.13 1 , but at least part of the above parameters may be added to a C-plane message of a segment type 3 or a segment type 5.

[0236] Fig.14 An example of signaling for MC-based RIM-RS transmission between DU and RU through U-plane messages according to an embodiment is shown. Fig.12 different, Fig.14 A method for controlling the RIM-RS processing of a RU based on fields in U-plane messages instead of fields in C-plane messages is described. Figure 2a According to an embodiment, the RU 220 may include an O-DU 251. The RU 220 may include an O-DU 251. Figure 2a According to an embodiment, the RU 220 may include an O-RU 253-1.

[0237] refer to Fig.14, in operation S1401, DU 210 may generate an M-plane message related to RIM-RS. According to an embodiment, the M-plane message may include a parameter for indicating whether the information including the IE for RIM-RS in the U-plane message described below is supported. In an embodiment, the M-plane message may indicate which network entity performs the calculation of the phase difference between the RIM-RS transmission and the general NR channel when compensating the phase difference of RU 220. According to an embodiment, the M-plane message may include information about the IQ value used for phase difference compensation. According to an embodiment, the M-plane message may include information about the difference between the RIM-RS center frequency and the center frequency of the system bandwidth, which difference is the compensation target. According to an embodiment, the M-plane message may include information about the RIM-RS center frequency. According to an embodiment, the M-plane message may include information about the center frequency of the system bandwidth. All parameters in the above-mentioned M-plane message may be sent through the M-plane, or at least a part of the parameters may be sent through the M-plane. A detailed description of each parameter may refer to Fig.10 .

[0238] In operation S1403, the DU 210 may transmit an M-plane message to the RU 220. The RU 220 may receive the M-plane message from the DU 210. The RU 220 may receive the M-plane message from the DU 210. Fig.14 Transmission of an M-plane message for RIM-RS processing (eg, CP position adjustment and RIM-RS phase difference compensation) of the RU 220 is shown, but the embodiments of the present disclosure are not limited thereto. In an alternative embodiment, operations S1401 and S1403 may be omitted.

[0239] In operation S1411, the DU 210 may generate a U-plane message including an IE for RIM-RS. The IE for RIM-RS may include at least one of information about RIM-RS symbols or information about phase difference compensation. According to an embodiment, the "reserved" field of the existing U-plane message may be replaced with at least one of information about RIM-RS symbols or information about phase difference compensation. In addition, according to an embodiment, at least one of information about RIM-RS symbols or information about phase difference compensation may be added to the U-plane message. The information about RIM-RS symbols may refer to information about Fig.10 Description of information about RIM-RS symbols in . Information about phase difference compensation may refer to information about Fig.10 Description of the information of phase difference compensation.

[0240] In operation S1413, the DU 210 may transmit a U-plane message. The RU 220 may receive the U-plane message from the DU 210.

[0241] In operation S1415, the RU 220 may perform position adjustment and phase difference compensation for the CP. The RU 220 may perform position adjustment for the CP. In the time domain, the RU 220 may perform position adjustment for the CP by cyclic shift of the RIM-RS symbol. In the frequency domain, the RU 220 may perform position adjustment for the CP by phase rotation of the RIM-RS symbol. The RU 220 may perform phase difference compensation. The RU 220 may perform phase difference compensation for the RIM-RS symbol. The RU 220 may perform phase difference compensation for each of the two symbols used for RIM-RS transmission. The RU 220 may perform phase difference compensation for each RIM-RS symbol.

[0242] exist Fig.14 In the embodiment of receiving a U-plane message including an IE for RIM-RS after receiving an M-plane message related to RIM-RS, the embodiment of the present disclosure is described, but the embodiments of the present disclosure are not limited thereto. If all parameters for position adjustment of CP and phase difference compensation of RIM-RS are sent through the U-plane message, the M-plane message may be omitted. According to an embodiment, operations S1401 and S1403 may be omitted.

[0243] exist Fig.14 In the embodiment, an operation for performing position adjustment of CP and phase difference compensation of RIM-RS is described based on an M-plane message related to RIM-RS and a U-plane message including an IE for RIM-RS. However, the embodiments of the present disclosure are not limited thereto. Based on the M-plane message, the U-plane message, and the C-plane message, RU 220 can perform RIM-RS processing. According to an embodiment, at least a part of the above parameters can be provided through an M-plane message, at least another part of the above parameters can be provided through an IE within a C-plane message, and the remaining part can be provided through an IE within a U-plane message. As an example, information indicating support for MC-based RIM-RS transmission and information about the center frequency of the system bandwidth can be provided to RU 220 through an M-plane message. RIM-RS symbol indication information can be provided to RU 220 through a C-plane message. Information about the carrier frequency of RIM-RS transmission can be provided to RU 220 through a U-plane message. As another example, information indicating support for MC-based RIM-RS transmission can be provided to RU 220 through an M-plane message. The RIM-RS symbol indication information can be provided to RU 220 through a C-plane message. The phase difference compensation value of each RIM-RS symbol may be provided to the RU 220 through a U-plane message.

[0244] Despite Fig.14Although not shown in the figure, according to an embodiment, the RU 220 may send capability information about whether information including an IE for RIM-RS in a new U-plane message is supported (i.e., MC-based RIM-RS transmission, or CP position adjustment in the RU and phase difference compensation of RIM-RS) to the DU 210. In addition, according to an embodiment, the RU 220 may send capability information indicating that calculation of the phase difference between RIM-RS transmission and a general NR channel is possible to the DU 210. In addition to the above-mentioned embodiments, in addition to the above-mentioned M-plane message, signaling for negotiating and transmitting required M-plane parameters may be performed on the fronthaul interface between the DU and the RU.

[0245] Fig.15 An example of a U-plane message for MC-based RIM-RS transmission according to an embodiment is shown. For RIM-RS processing in the RU, the IE of the U-plane or the "reserved" field can be used. The DU can send a U-plane message including an IE for MC-based RIM-RS transmission to the RU. Fig.15 The U-plane message illustrated in the example may be in Fig.14 The U-plane message generated in operation S1411.

[0246] The information for MC-based RIM-RS transmission according to the embodiment may be used together with a segment of a C-plane message of a specified type. Here, the C-plane message may be used together with Fig.15 In the case of coupling the C-plane with the U-plane via "sectionId", the C-plane message "sectionId" identifies the individual data segment described by the data segment description in the C-plane message. Through "sectionId", it can be mapped to the corresponding C-plane message (and segment type) related to the U-plane data segment. According to an embodiment, the segment type of the C-plane message can be "1". According to an embodiment, the segment type of the C-plane message can be "3". According to an embodiment, the segment type of the C-plane message can be "5".

[0247] refer to Fig.15 , the U-plane message 1510 may include multiple fields. The segment type of the U-plane message 1510 may be "1". Fig.15 In the embodiment, the U-plane message related to the segment type 1 is illustrated, but the description of the embodiments described below can also be applied to another segment type (for example, segment type 3, segment type 5).

[0248] DU 210 may add newly defined octets to the U-plane message. Fig.11 Additional bytes for the parameters described in are added to the U-plane message.

[0249] According to an embodiment, the U-plane message 1500 may include an octet, i.e., an 8-bit field, including RIM-RS symbol indication information "rimrsSymbolInd" 1511 as a new parameter. The RIM-RS symbol indication information 1511 may indicate a specific RIM-RS symbol among two symbols of the RIM-RS transmission corresponding to the segment of the U-plane message 1500. Fig.15 Only the RIM-RS symbol indication information 1511 is shown, but other parameters may also be added. For example, a field including the phase difference compensation information "phaseDecompIq" (or at least one of the first phase difference compensation information "phaseDecompIq_0" or the second phase difference compensation information "phaseDecompIq_1") may be added to the U-plane message. In addition, for example, a field including the phase difference information "phaseDifference" may be added to the U-plane message. In addition, for example, a field including the frequency information "rimCenterFreq" indicating the center frequency of the RIM-RS may be added to the U-plane message. A specific description of each parameter is as follows.

[0250] -RIM-RS symbol indication information "rimrsSymbolInd" may indicate a RIM-RS symbol associated with a corresponding segment of the U-plane message. RIM-RS transmission may require two symbols. For example, the RIM-RS symbol indication information may consist of one octet, i.e., 8 bits. The 8 bits may indicate at least one of the first RIM-RS symbol or the second RIM-RS symbol among the two symbols of the RIM-RS transmission.

[0251] -The phase difference compensation information "phaseDecompIq" may include an IQ value for compensating the phase of the RIM-RS symbol. In this article, the RIM-RS symbol may be indicated by the RIM-RS symbol indication information. For example, the phase difference compensation information may consist of 4 octets, i.e., 32 bits. As an example, 32 bits may indicate an IQ value for compensating the phase of the RIM-RS symbol. According to another embodiment, instead of the phase difference compensation information "phaseDecompIq", the first phase difference compensation information "phaseDecompIq_0" and the second phase difference compensation information "phaseDecompIq_1" may be used.

[0252] -The phase difference information "phaseDifference" indicates the difference between the frequency of the RIM-RS and the carrier frequency of the system bandwidth. For example, the phase difference information may consist of 4 octets, i.e., 32 bits. As an example, 32 bits may indicate the difference between the center frequency of the RIM-RS and the center frequency of the system bandwidth in a specified unit (e.g., 100 kHz, 10 kHz).

[0253] - The frequency information (eg, "rimCenterFreq") may indicate the center frequency of the RIM-RS. For example, the frequency information may indicate the center frequency of the RIM-RS in 4 octets (ie, 32 bits). The frequency information may indicate the absolute radio frequency channel number (ARFCN) of the center frequency of the RIM-RS.

[0254] For compatibility, the above parameters may be optionally included in the U-plane message. Optional parameters may be activated based on the parameters defined in the M-plane. In addition, unlike the RIM-RS symbol indication information, other parameters may be omitted in some sections. Fig.15 A U-plane message 1500 corresponding to segment type 1 is shown in FIG. 1 , but at least part of the above parameters may be added to a U-plane message combined with segment type 3 or segment type 5.

[0255] The parameters according to an embodiment of the present disclosure can be used for RIM-RS symbols modulated by MC compression technology. Therefore, the compression technology that may need to be indicated in the U-plane message is related to MC. According to an embodiment, in the case where the static compression technology defined in the M-plane is "Modulation compression" or "Mod-compr + selective RE sending", the U-plane message may include at least one of the RIM-RS indication information or the phase difference information. In addition, according to an embodiment, in the case where the compression method (for example, 4-bit "udCompMeth") in the U-plane message including the RIM-RS indication information or the phase difference information is "Modulation compression" ("0100b" in Table 1) or "Mod-compr + selective REsending" ("0110b" in Table 1), the U-plane message may include at least one of the RIM-RS indication information or the phase difference information.

[0256] pass Figures 10 to 15 Parameters and related operations shown, RU 220 can obtain parameters required for RIM-RS related processing from DU 210.

[0257] The RIM-RS may be compressed using modulation compression technology. After constellation mapping, the IQ bits corresponding to the compressed symbols may be provided from the DU 210 to the RU 220 via a U-plane message. Due to the modulation compression technology, the position adjustment of the CP for RIM-RS transmission and the phase difference compensation between the carrier frequency for RIM-RS transmission and the carrier frequency of the bandwidth may be required in the RU 220. Therefore, the DU 210 according to an embodiment of the present disclosure may provide the RU 220 with at least one parameter for RIM-RS processing based on the segment extension information in the C-plane message, the IE in the C-plane message, or the IE in the U-plane message, or a combination thereof. The RU 220 may perform cyclic shift (or phase rotation in the frequency domain) and phase difference compensation of the RIM-RS CP based on at least one parameter. In addition, in another embodiment, the overhead of the C-plane message or the U-plane message may be reduced by setting at least a portion of the above parameters by an M-plane message.

[0258] According to an embodiment, a method performed by a radio unit (RU) may include receiving a control plane (C-plane) message including segment extension information from a distributed unit (DU) via a fronthaul interface. The method may include receiving a user plane (U-plane) message including a remote interference management reference signal (RIM-RS) symbol from the DU via the fronthaul interface. The method may include performing phase difference compensation for the RIM-RS symbol and adjusting the position of a cyclic prefix (CP) of the RIM-RS symbol. The segment extension information may include at least one of indication information for indicating at least one RIM-RS symbol in the RIM-RS symbol or compensation information related to phase difference compensation.

[0259] According to an embodiment, the indication information may indicate at least one of the first RIM-RS symbol or the second RIM-RS symbol in the RIM-RS symbols. The indication information may be used for position adjustment of the CP.

[0260] According to an embodiment, the compensation information may include at least one of the following: an in-phase / quadrature (IQ) value for compensating for a phase difference associated with a difference between a carrier frequency of a first RIM-RS symbol in the RIM-RS symbol and a carrier frequency of the system bandwidth, or an IQ value for compensating for a phase difference associated with a difference between a carrier frequency of a second RIM-RS symbol in the RIM-RS symbol and a carrier frequency of the system bandwidth.

[0261] According to an embodiment, the compensation information may include carrier frequency information used for RIM-RS transmission, or information about a difference between a carrier frequency used for RIM-RS transmission and a carrier frequency of a system bandwidth.

[0262] According to an embodiment, the RIM-RS symbol may be a Quadrature Phase Shift Keying (QPSK) modulation symbol based on Modulation Compression (MC).

[0263] According to an embodiment, the method may include sending an M-plane message including capability information to the DU via a fronthaul interface before receiving the C-plane message from the DU. The capability information may be used to indicate whether the RU supports at least one of the indication information or the compensation information.

[0264] According to an embodiment, the method may include receiving an M-plane message from the DU via a fronthaul interface before receiving the C-plane message from the DU. The M-plane message may include at least one of the following: information indicating whether position adjustment of the CP and phase difference compensation of the RU are supported, information about an in-phase / quadrature (IQ) value for compensating the phase difference, information about a RIM-RS center frequency, information about a center frequency of a system bandwidth, or information about a difference between a RIM-RS center frequency and a center frequency of the system bandwidth.

[0265] According to an embodiment, a method performed by a distributed unit (DU) may include sending a control plane (C-plane) message including segment extension information to a radio unit (RU) via a fronthaul interface. The method may include sending a user plane (U-plane) message including a RIM-RS symbol to the RU via the fronthaul interface. The segment extension information may be used to perform phase difference compensation for the RIM-RS symbol and position adjustment of a cyclic prefix (CP) of the RIM-RS symbol. The segment extension information may include at least one of indication information for indicating at least one RIM-RS symbol in the RIM-RS symbol or compensation information related to phase difference compensation.

[0266] According to an embodiment, the indication information may indicate at least one of the first RIM-RS symbol or the second RIM-RS symbol among the RIM-RS symbols.

[0267] According to an embodiment, the compensation information may include at least one of the following: an in-phase / quadrature (IQ) value for compensating for a phase difference associated with a difference between a carrier frequency of a first RIM-RS symbol in the RIM-RS symbol and a carrier frequency of the system bandwidth, or an IQ value for compensating for a phase difference associated with a difference between a carrier frequency of a second RIM-RS symbol in the RIM-RS symbol and a carrier frequency of the system bandwidth.

[0268] According to an embodiment, the compensation information may include carrier frequency information used for RIM-RS transmission, or information about a difference between a carrier frequency used for RIM-RS transmission and a carrier frequency of a system bandwidth.

[0269] According to an embodiment, the RIM-RS symbol may be a Quadrature Phase Shift Keying (QPSK) modulation symbol based on Modulation Compression (MC).

[0270] According to an embodiment, the method may include receiving an M-plane message including capability information from the RU via a fronthaul interface before sending the C-plane message to the RU. The capability information may be used to indicate whether the RU supports at least one of the indication information or the compensation information.

[0271] According to an embodiment, the method may include sending an M-plane message to the RU via a fronthaul interface before sending the C-plane message to the RU. The M-plane message may include at least one of the following: information indicating whether position adjustment of the CP and phase difference compensation of the RU are supported, information about an in-phase / quadrature (IQ) value for compensating the phase difference, information about a RIM-RS center frequency, information about a center frequency of a system bandwidth, or information about a difference between a RIM-RS center frequency and a center frequency of a system bandwidth.

[0272] According to an embodiment, an electronic device executed by a radio unit (RU) may include: a fronthaul transceiver, at least one radio frequency (RF) transceiver, and at least one processor coupled to the fronthaul transceiver and the at least one RF transceiver. The at least one processor may be configured to receive a control plane (C-plane) message including segment extension information from a distributed unit (DU) via a fronthaul interface. The at least one processor may be configured to receive a user plane (U-plane) message including a remote interference management reference signal (RIM-RS) symbol from the DU via a fronthaul interface. The at least one processor may be configured to perform phase difference compensation for the RIM-RS symbol and position adjustment of the cyclic prefix (CP) of the RIM-RS symbol. The segment extension information may include at least one of indication information for indicating at least one RIM-RS symbol in the RIM-RS symbol or compensation information related to phase difference compensation.

[0273] According to an embodiment, the indication information may indicate at least one of the first RIM-RS symbol or the second RIM-RS symbol in the RIM-RS symbols, and the indication information may be used for position adjustment of the CP.

[0274] According to an embodiment, the compensation information may include at least one of the following: an in-phase / quadrature (IQ) value for compensating for a phase difference associated with a difference between a carrier frequency of a first RIM-RS symbol in the RIM-RS symbol and a carrier frequency of the system bandwidth, or an IQ value for compensating for a phase difference associated with a difference between a carrier frequency of a second RIM-RS symbol in the RIM-RS symbol and a carrier frequency of the system bandwidth.

[0275] According to an embodiment, the compensation information may include carrier frequency information used for RIM-RS transmission, or information about a difference between a carrier frequency used for RIM-RS transmission and a carrier frequency of a system bandwidth.

[0276] According to an embodiment, the RIM-RS symbol may be a Quadrature Phase Shift Keying (QPSK) modulation symbol based on Modulation Compression (MC).

[0277] According to an embodiment, the at least one processor may be configured to send an M-plane message including capability information to the DU via a fronthaul interface before receiving a C-plane message from the DU. The capability information may be used to indicate whether the RU supports at least one of the indication information or the compensation information.

[0278] According to an embodiment, the at least one processor may be configured to receive an M-plane message from the DU via the fronthaul interface before receiving the C-plane message from the DU. The M-plane message may include at least one of the following: information indicating whether position adjustment of the CP and phase difference compensation of the RU are supported, information about an in-phase / quadrature (IQ) value for compensating the phase difference, information about a RIM-RS center frequency, information about a center frequency of a system bandwidth, or information about a difference between a RIM-RS center frequency and a center frequency of a system bandwidth.

[0279] According to an embodiment, an electronic device executed by a distributed unit (DU) may include: at least one transceiver including a fronthaul transceiver; and at least one processor coupled to the at least one transceiver. The at least one processor may be configured to send a control plane (C-plane) message including segment extension information to a radio unit (RU) via a fronthaul interface. The at least one processor may be configured to send a user plane (U-plane) message including a RIM-RS symbol to the RU via a fronthaul interface. The segment extension information may be used to perform phase difference compensation for the RIM-RS symbol and position adjustment of the cyclic prefix (CP) of the RIM-RS symbol. The segment extension information may include at least one of indication information for indicating at least one RIM-RS symbol in the RIM-RS symbol or compensation information related to phase difference compensation.

[0280] According to an embodiment, the indication information may indicate at least one of the first RIM-RS symbol or the second RIM-RS symbol among the RIM-RS symbols.

[0281] According to an embodiment, the compensation information may include at least one of the following: an in-phase / quadrature (IQ) value for compensating for a phase difference associated with a difference between a carrier frequency of a first RIM-RS symbol in the RIM-RS symbol and a carrier frequency of the system bandwidth, or an IQ value for compensating for a phase difference associated with a difference between a carrier frequency of a second RIM-RS symbol in the RIM-RS symbol and a carrier frequency of the system bandwidth.

[0282] According to an embodiment, the compensation information may include carrier frequency information used for RIM-RS transmission, or information about a difference between a carrier frequency used for RIM-RS transmission and a carrier frequency of a system bandwidth.

[0283] According to an embodiment, the RIM-RS symbol may be a Quadrature Phase Shift Keying (QPSK) modulation symbol based on Modulation Compression (MC).

[0284] According to an embodiment, the at least one processor may be configured to receive an M-plane message including capability information from the RU via a fronthaul interface before sending the C-plane message to the RU. The capability information may be used to indicate whether the RU supports at least one of the indication information or the compensation information.

[0285] According to an embodiment, at least one processor may be configured to send an M-plane message to the RU via a fronthaul interface before sending a C-plane message to the RU. The M-plane message may include at least one of the following: information indicating whether position adjustment of the CP and phase difference compensation of the RU are supported, information about an in-phase / quadrature (IQ) value for compensating the phase difference, information about a RIM-RS center frequency, information about a center frequency of a system bandwidth, or information about a difference between a RIM-RS center frequency and a center frequency of a system bandwidth.

[0286] According to an embodiment, a non-transitory computer-readable medium is provided. The non-transitory computer-readable medium may include a memory storing a program including instructions. When the instructions are executed by a processor, a distributed unit (DU) receives a control plane (C-plane) message including segment extension information from a distributed unit (DU) via a fronthaul interface. When the instructions are executed by the processor, the DU receives a user plane (U-plane) message including a remote interference management reference signal (RIM-RS) symbol from the DU via a fronthaul interface. When the instructions are executed by the processor, the DU performs phase difference compensation for the RIM-RS symbol and position adjustment of the cyclic prefix (CP) of the RIM-RS symbol. The segment extension information may include at least one of indication information for indicating at least one RIM-RS symbol in the RIM-RS symbol or compensation information related to phase difference compensation.

[0287] According to an embodiment, a non-transitory computer-readable medium is provided. The non-transitory computer-readable medium may include a memory storing a program including instructions. These instructions, when executed by a processor, cause a radio unit (RU) to send a control plane (C-plane) message including segment extension information to the RU via a fronthaul interface. The instructions, when executed by the processor, cause the RU to send a user plane (U-plane) message including RIM-RS symbols to the RU via a fronthaul interface. The segment extension information may be used to perform phase difference compensation for the RIM-RS symbol and position adjustment of the cyclic prefix (CP) of the RIM-RS symbol. The segment extension information may include at least one of indication information for indicating at least one RIM-RS symbol in the RIM-RS symbol or compensation information related to phase difference compensation.

[0288] The various embodiments set forth herein may be implemented as software including one or more instructions stored in a storage medium readable by a machine (e.g., a device that performs the functions of DU 210 or a device that performs the functions of RU 220). For example, a processor (e.g., processor 330, processor 380) of a machine (e.g., DU 210, RU 220) may call at least one of the one or more instructions stored in the storage medium and run with or without one or more other components under the control of the processor. This allows the machine to be operated to perform at least one function according to at least one instruction called. The one or more instructions may include code generated by a compiler or code executable by an interpreter. The machine-readable storage medium may be provided in the form of a non-transitory storage medium. Among them, the term "non-transitory" only means that the storage medium is a tangible device and does not include signals (e.g., electromagnetic waves), but the term does not distinguish between a case where data is semi-permanently stored in a storage medium and a case where data is temporarily stored in a storage medium. O-RAN implements the configuration of a virtualized intelligent network with a standardized open interface. For network virtualization, the operation according to the embodiment may be implemented in the form of a recording medium (e.g., a memory).

[0289] According to an embodiment, the method according to various embodiments of the present disclosure may be included and provided in a computer program product. The computer program product may be traded as a product between a seller and a buyer. The computer program product may be distributed in the form of a machine-readable storage medium (e.g., a compact disc read-only memory (CD-ROM)), or distributed online (e.g., downloaded or uploaded) via an application store (e.g., PlayStore™), or distributed directly between two user devices (e.g., smart phones). If distributed online, at least a portion of the computer program product may be temporarily generated or at least temporarily stored in a machine-readable storage medium, such as a memory of a manufacturer's server, a server of an application store, or a relay server.

[0290] According to various embodiments, each of the above-mentioned components (e.g., a module or a program) may include a single entity or multiple entities, and some of the multiple entities may be separately arranged in different components. According to various embodiments, one or more of the above-mentioned components may be omitted, or one or more other components may be added. Alternatively or additionally, multiple components (e.g., modules or programs) may be integrated into a single component. In this case, according to various embodiments, the integrated component may still perform one or more functions of each of the multiple components in the same or similar manner as performed by the corresponding components in the multiple components before integration. According to various embodiments, the operations performed by a module, a program or another component may be performed sequentially, in parallel, repeatedly or heuristically, or one or more operations may be performed or omitted in a different order, or one or more other operations may be added.

[0291] The methods according to the embodiments described in the claims or specification of the present disclosure may be implemented in the form of hardware, software, or a combination of hardware and software.

[0292] In the case of being implemented as software, a computer-readable storage medium for storing one or more programs (software modules) may be provided. One or more programs stored in the computer-readable storage medium are configured to be executed by one or more processors in an electronic device. One or more programs include instructions for causing the electronic device to execute the method according to the embodiments described in the claims or description of the present disclosure.

[0293] Such a program (software module, software) may be stored in a random access memory, a non-volatile memory including a flash memory, a read-only memory (ROM), an electrically erasable programmable read-only memory (EEPROM), a magnetic disk storage device, a compact disk-ROM (CD-ROM), an optical storage device (digital versatile disk (DVD) or other format), or a magnetic tape cassette. Alternatively, it may also be stored in a memory configured with a combination of some or all of them. In addition, multiple configuration memories may be included.

[0294] In addition, the program can be stored in an attachable storage device that can be accessed through a communication network such as the Internet, an intranet, a local area network (LAN), a wide area network (WAN), or a storage area network (SAN), or a combination thereof. Such a storage device can be connected to the device that performs the embodiments of the present disclosure through an external port. In addition, a separate storage device on the communication network can also be connected to the device that performs the embodiments of the present disclosure.

[0295] In the above specific embodiments of the present disclosure, the components included in the present disclosure are expressed in the singular or plural according to the specific embodiments presented. However, for ease of explanation, singular or plural expression is appropriately selected according to the presented situation, and the present disclosure is not limited to singular or plural components, and even components expressed in the plural may be configured in the singular, or components expressed in the singular may be configured in the plural.

[0296] While specific embodiments have been described in the detailed description of the present disclosure, it is of course possible that various modifications are possible without departing from the scope of the present disclosure.

Claims

1. A method performed by a radio unit, namely, a RU, the method comprising: receiving a control plane message including segment extension information from a distributed unit via a fronthaul interface, the distributed unit being the DU, the control plane being the C-plane; Receiving a user plane message including a remote interference management reference signal symbol from the DU via the fronthaul interface, the remote interference management reference signal being RIM-RS, and the user plane being U-plane; Performing phase difference compensation for the RIM-RS symbol and adjusting the position of the cyclic prefix of the RIM-RS symbol, the cyclic prefix being CP, and The segment extension information includes at least one of indication information for indicating at least one RIM-RS symbol in the RIM-RS symbols or compensation information related to the phase difference compensation.

2. The method according to claim 1, in, The indication information indicates at least one of a first RIM-RS symbol or a second RIM-RS symbol in the RIM-RS symbols, and The indication information is used for adjusting the position of the CP.

3. The method according to any one of claims 1 to 2, in, The compensation information includes at least one of the following: an in-phase / quadrature value for compensating for a phase difference associated with a difference between a carrier frequency of a first RIM-RS symbol in the RIM-RS symbols and a carrier frequency of a system bandwidth, the in-phase / quadrature being IQ, or An IQ value for compensating for a phase difference associated with a difference between a carrier frequency of a second RIM-RS symbol in the RIM-RS symbols and a carrier frequency of the system bandwidth.

4. The method according to any one of claims 1 to 3, in, The compensation information includes carrier frequency information used for RIM-RS transmission, or information on a difference between a carrier frequency of the RIM-RS transmission and a carrier frequency of a system bandwidth.

5. The method according to any one of claims 1 to 4, in, The RIM-RS symbol is a quadrature phase shift keying modulation symbol based on modulation compression, the modulation compression is MC, and the quadrature phase shift keying is QPSK.

6. The method according to any one of claims 1 to 5, further comprising: before receiving the C-plane message from the DU, sending an M-plane message including capability information to the DU via the fronthaul interface, The capability information is used to indicate whether the RU supports at least one of the indication information or the compensation information.

7. An electronic device executed by a wireless unit, the wireless unit being RU, the electronic device comprising: fronthaul transceiver; at least one radio frequency transceiver, wherein the radio frequency is RF; as well as at least one processor coupled to the fronthaul transceiver and the at least one RF transceiver, The at least one processor is configured to execute the method according to any one of claims 1 to 6.

8. A method performed by a distributed unit, the distributed unit being DU, the method comprising: Sending a control plane message including the segment extension information to a wireless unit via a fronthaul interface, wherein the wireless unit is the RU and the control plane is the C-plane; Sending a user plane message including a RIM-RS symbol to the RU via the fronthaul interface, the user plane being a U plane; The segment extension information is used to perform phase difference compensation for the RIM-RS symbol and position adjustment for the cyclic prefix of the RIM-RS symbol, the cyclic prefix being CP, and The segment extension information includes at least one of indication information for indicating at least one RIM-RS symbol in the RIM-RS symbols or compensation information related to the phase difference compensation.

9. The method according to claim 8, in, The indication information indicates at least one of a first RIM-RS symbol or a second RIM-RS symbol among the RIM-RS symbols.

10. The method according to any one of claims 8 to 9, in, The compensation information includes at least one of the following: an in-phase / quadrature value for compensating for a phase difference associated with a difference between a carrier frequency of a first RIM-RS symbol in the RIM-RS symbols and a carrier frequency of a system bandwidth, the in-phase / quadrature being IQ, or An IQ value for compensating for a phase difference associated with a difference between a carrier frequency of a second RIM-RS symbol in the RIM-RS symbols and a carrier frequency of the system bandwidth.

11. The method according to any one of claims 8 to 10, in, The compensation information includes carrier frequency information used for RIM-RS transmission, or information on a difference between a carrier frequency of the RIM-RS transmission and a carrier frequency of a system bandwidth.

12. The method according to any one of claims 8 to 11, in, The RIM-RS symbol is a quadrature phase shift keying modulation symbol based on modulation compression, the modulation compression is MC, and the quadrature phase shift keying is QPSK.

13. The method according to any one of claims 8 to 12, further comprising: before sending the C-plane message to the RU, receiving an M-plane message including capability information from the RU via the fronthaul interface, The capability information is used to indicate whether the RU supports at least one of the indication information or the compensation information.

14. An electronic device executed by a distributed unit, the distributed unit being DU, the electronic device comprising: at least one transceiver, the at least one transceiver comprising a fronthaul transceiver; as well as at least one processor coupled to the at least one transceiver, The at least one processor is configured to execute the method according to any one of claims 8 to 13.

15. A non-transitory computer-readable medium comprising a memory storing a program comprising instructions, in, When the instructions are executed by a processor, the distributed unit executes the method according to any one of claims 1 to 6, or the wireless unit executes the method according to any one of claims 8 to 13, wherein the distributed unit is DU and the wireless unit is RU.

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