Multi-carrier-based radio unit providing common operation function of multiple operator and in-building solution including the same

Abstract

A radio unit providing a common operational function for multiple carriers based on a multi-carrier system and an in-building solution including the same are disclosed. The in-building radio unit of the in-building solution providing a common operational function for multiple carriers based on a multi-carrier system according to one embodiment of the present invention may include: a base station connection unit configured to be individually connected to a plurality of base station devices corresponding to each of the multiple carriers and capable of receiving at least one carrier signal from each of the plurality of base station devices; a communication relay unit configured to form a communication frame for at least one distributed terminal unit deployed in an in-building environment and transmitting the carrier signal to the distributed terminal unit through the communication frame; and a filter unit configured to selectively turn on or off a predefined payload for each of the multiple carriers in the communication frame depending on whether the carrier signal is received.

Description

Technology Field

[0001] The present invention relates to a radio unit providing common operational functions for multiple operators based on a multi-carrier system, and an in-building solution including the same. Background Technology

[0002] Recently, in order to achieve high data transmission rates, 5G communication systems are being considered for implementation in the mmWave band, for example, the 60 GHz band. To mitigate path loss and increase the transmission distance of radio waves in the mmWave band, beamforming, massive MIMO, full Dimensional MIMO (FD-MIMO), array antenna, analog beamforming, and large scale antenna technologies are being discussed for 5G communication systems.

[0003] Among these, beamforming is a technology that focuses wireless signals in a specific direction by changing the amplitude and phase of signals supplied to multiple antennas from both the user terminal and the base station. It enables efficient and smooth data transmission and reception in high-frequency wireless communication, offering the advantage of increasing coverage without increasing the number of base stations.

[0004] Meanwhile, the Open Radio Access Network (O-RAN), established by operators and equipment providers in a mixed system of 4G and 5G communication systems, defines new Network Element (NE) and Interface specifications based on existing 3GPP standards and presents the O-RAN structure.

[0005] Radio units (RUs) in in-building environments have sufficient capacity but relatively small coverage. This is because radio waves cannot be transmitted efficiently inside a building due to obstacles such as walls, glass, and inter-floor isolation.

[0006] Furthermore, in in-building environments, as the propagation range shortens with higher frequencies, it is more economical to distribute antennas rather than increase the number of in-building radio units to expand coverage; however, there is a problem in that as the number of antennas increases in the uplink (reverse) direction, reverse noise rises in proportion to that number.

[0007] Furthermore, because the uplink signal strength is weak due to the terminal's limited power, the weak reverse signal is subject to interference from noise, further reducing reverse coverage. Additionally, reverse noise degrades the reverse Signal-to-Noise Ratio (SINR), thereby decreasing throughput.

[0008] In other words, there is a problem where the noise figure (NF) increases as the number of distributed termination units increases. This is because in-building radio units are not noise-free devices, so the noise figure can increase as their number increases.

[0009] Therefore, there is a need for technological development to resolve the problem of uplink noise that may occur when multiple distributed end units are required to be connected to a single base station, and such a problem can be resolved if beamforming technology can be applied to in-building radio units.

[0010] The technology forming the background of this invention is disclosed in Korean Registered Patent Publication No. 10-1340108. The problem to be solved

[0011] The present invention aims to solve the problems of the aforementioned conventional technology by providing a radio unit that offers a common operation function for multiple operators based on a multi-carrier approach, and an in-building solution including the same, which allows a single in-building radio unit to be shared among multiple telecommunication operators, thereby resolving the issue of facility saturation for facility management agencies and reducing the cost burden on telecommunication operators resulting from facility investment.

[0012] The present invention aims to solve the problems of the aforementioned conventional technology by providing an in-building system that utilizes an index table corresponding to a distributed path using a beamforming element capable of eliminating uplink noise that accumulates as the number of distributed termination units increases in an in-building radio unit (or in-building O-RU).

[0013] The present invention aims to solve the problems of the aforementioned conventional technology by providing an in-building system using an index table corresponding to a distributed path utilizing beamforming elements, which not only prevents interference between distributed termination units by distributing communication paths for multiple distributed termination units operating in an in-building environment using beamforming information, but also reduces power consumption by alleviating the burden on the downlink amplifier.

[0014] However, the technical problems that the embodiments of the present invention aim to solve are not limited to the technical problems described above, and other technical problems may exist. means of solving the problem

[0015] As a technical means for achieving the above-mentioned technical problem, an in-building radio unit of an in-building solution providing a common operation function for multiple carriers based on a multi-carrier according to one embodiment of the present invention may include: a base station connection unit configured to be individually connected to a plurality of base station devices corresponding to each of the multiple carriers and capable of receiving at least one carrier signal from each of the plurality of base station devices; a communication relay unit configured to form a communication frame for at least one distributed end unit deployed in an in-building environment and transmitting the carrier signal to the distributed end unit through the communication frame; and a filter unit configured to selectively turn on or off a predefined payload of each of the multiple carriers for the communication frame depending on whether the carrier signal is received.

[0016] In addition, the base station connection unit may be provided with a plurality of cables for receiving the operator signal from each of the plurality of base station devices.

[0017] In addition, the base station connection unit can be connected to each of the plurality of base station devices using the eCPRI method.

[0018] In addition, the above-mentioned operator signal may be assigned mutually distinguishable frequency bands corresponding to each of the multiple operators.

[0019] In addition, the filter unit can control the digital filter so that an output signal of the frequency band corresponding to the operator signal received through the base station connection unit is output through the distributed termination unit.

[0020] In addition, the communication relay unit can determine the allocation pattern of the payload for the communication frame based on the number of the plurality of base station devices.

[0021] In addition, the base station connection unit can be individually connected to up to four different base station devices.

[0022] Meanwhile, an in-building solution providing a common operation function for multiple carriers based on a multi-carrier according to one embodiment of the present invention may include a radio unit that is individually connected to a plurality of base station devices corresponding to each of the multiple carriers, receives at least one carrier signal from each of the plurality of base station devices, and transmits the carrier signal to a distributed terminal unit through a predefined communication frame, and a distributed terminal unit that outputs an output signal corresponding to the carrier signal received from the radio unit and is allocated such that the frequency bands corresponding to each of the multiple carriers are mutually distinguishable.

[0023] Meanwhile, a method for operating an in-building radio unit of an in-building solution providing a common operation function for multiple operators based on a multi-carrier according to one embodiment of the present invention may include the steps of: configuring a communication frame defined for at least one distributed end unit deployed in an in-building environment, wherein the location of a payload corresponding to each of the multiple operators is predetermined; receiving at least one operator signal from each of a plurality of base station devices corresponding to each of the multiple operators; and selectively turning on or off each payload of the communication frame depending on whether the operator signal is received.

[0024] Meanwhile, a base station device of an in-building solution using an index table corresponding to a distributed path utilizing a beamforming element according to one embodiment of the present invention may include a reference information acquisition unit that acquires an index table corresponding to a distributed path for a plurality of distributed end units from a radio unit, and a communication execution unit that transmits and receives signals via the radio unit to a terminal connected to a predetermined distributed end unit among the plurality of distributed end units based on the index table.

[0025] In addition, the index table may be information for matching the beam ID and the distributed termination unit using beamforming information.

[0026] In addition, an extension unit that transmits a signal may be provided between the radio unit and the distributed termination unit.

[0027] In addition, based on the above index table, the SSB index and CSI-RS index extracted from the extension unit and the distributed termination unit and the beamforming information can be matched, respectively.

[0028] In addition, the base station device can be connected to a radio unit via a wired connection for communication.

[0029] Meanwhile, a radio unit of an in-building solution using an index table corresponding to a distributed path utilizing a beamforming element according to one embodiment of the present invention may include a matching unit that generates an index table corresponding to a distributed path for a plurality of distributed end units, and a communication relay unit that transmits the index table to a base station device, transmits a signal received from the base station device to a predetermined distributed end unit among the plurality of distributed end units based on the index table, and transmits a signal received from a terminal connected to the predetermined distributed end unit to the base station device.

[0030] In addition, the matching unit may generate the index table for matching the beam ID and the distributed termination unit using beamforming information.

[0031] In addition, the matching unit may generate the index table such that any one of the plurality of antennas provided in each of the plurality of distributed termination units is selectively activated at a specific time.

[0032] In addition, the matching unit can match the extension unit and the distributed termination unit, respectively, based on the SSB index and CSI-RS index extracted from the beamforming information.

[0033] In addition, the matching unit can update the index table on a slot basis.

[0034] In addition, the radio unit can be connected to the distributed termination unit via a wired connection.

[0035] Meanwhile, an in-building system using an index table corresponding to a distributed path utilizing a beamforming element according to one embodiment of the present invention may include a radio unit that generates an index table corresponding to a distributed path for a plurality of distributed end units deployed in an in-building environment and transmits the index table to a base station device, and a base station device that transmits and receives signals via the radio unit to a terminal connected to a predetermined distributed end unit among the plurality of distributed end units based on the index table.

[0036] In addition, the radio unit can transmit a signal received from the base station device to a predetermined distributed end unit based on the index table among the plurality of distributed end units, and transmit a signal received from a terminal connected to the predetermined distributed end unit to the base station device.

[0037] In addition, the radio unit can support a fronthaul interface with the base station device.

[0038] The means for solving the problem described above are merely exemplary and should not be interpreted as intended to limit the present invention. In addition to the exemplary embodiments described above, additional embodiments may exist in the drawings and the detailed description of the invention. Effects of the invention

[0039] According to the means for solving the problem of the present invention described above, a single in-building radio unit can be shared among multiple telecommunication operators, thereby resolving the problem of facility saturation of facility management agencies and reducing the cost burden on telecommunication operators due to facility investment, etc., and a radio unit providing a common operation function for multiple operators based on a multi-carrier approach and an in-building solution including the same can be provided.

[0040] According to the means for solving the problem of the present invention described above, an in-building system can be provided that utilizes an index table corresponding to a distributed path using a beamforming element capable of eliminating uplink noise that accumulates as the number of distributed termination units increases in an in-building radio unit (or in-building O-RU).

[0041] According to the means for solving the problem of the present invention described above, by distributing communication paths for a plurality of distributed termination units operating in an in-building environment using beamforming information, it is possible to provide an in-building system using an index table corresponding to a distributed path utilizing a beamforming element, which not only prevents interference between distributed termination units but also reduces power consumption by alleviating the burden on the downlink amplifier.

[0042] However, the effects obtainable from this invention are not limited to those described above, and other effects may exist. Brief explanation of the drawing

[0043] FIG. 1 is a schematic diagram of an in-building system using an index table corresponding to a distributed path utilizing a beamforming element according to one embodiment of the present invention. FIGS. 2a and 2b are conceptual diagrams illustrating the common operation functions of multiple operators based on a multi-carrier in-building system according to one embodiment of the present invention. FIG. 3 is a drawing for explaining beamforming technology according to one embodiment of the present invention. FIG. 4 is a diagram showing beamforming information and distributed termination units that match each other according to one embodiment of the present invention. FIG. 5 is a diagram showing the connection relationship between an in-building radio unit and a distributed termination unit according to one embodiment of the present invention. FIG. 6 is a diagram exemplarily showing the matching results of another beam ID and a distributed termination unit in one embodiment of the present invention. Figure 7 is a diagram illustrating the noise of the uplink signal for a base station. FIG. 8 is a schematic diagram of a base station device of an in-building solution using an index table corresponding to a distributed path utilizing a beamforming element according to one embodiment of the present invention. Figure 9 is a schematic diagram of a radio unit of an in-building solution using an index table corresponding to a distributed path utilizing beamforming elements. FIG. 10 is a flowchart of the operation method of an in-building radio unit of an in-building solution that provides a common operation function for multiple operators based on a multi-carrier according to one embodiment of the present invention. Specific details for implementing the invention

[0044] Embodiments of the present invention are described below with reference to the attached drawings to enable those skilled in the art to easily implement the invention. However, the present invention may be embodied in various different forms and is not limited to the embodiments described herein. Furthermore, in order to clearly explain the present invention in the drawings, parts unrelated to the explanation have been omitted, and similar parts throughout the specification are denoted by similar reference numerals.

[0045] Throughout this specification, when a part is described as being "connected" to another part, this includes not only cases where they are "directly connected," but also cases where they are "electrically connected" or "indirectly connected" with other elements interposed between them.

[0046] Throughout the entire specification, when a component is described as being located "on," "on top," "on top," "under," "on bottom," or "on bottom" of another component, this includes not only cases where the component is in contact with the other component but also cases where another component exists between the two components.

[0047] Throughout this specification, when a part is described as "comprising" a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but may include additional components.

[0048] The present invention relates to a radio unit providing common operational functions for multiple operators based on a multi-carrier system, and an in-building solution including the same.

[0049] FIG. 1 is a schematic diagram of an in-building system using an index table corresponding to a distributed path utilizing a beamforming element according to one embodiment of the present invention.

[0050] Referring to FIG. 1, an in-building system according to one embodiment of the present invention may include a base station device (10), a radio unit (21), an extension unit (22), a distributed termination unit (23), and a user terminal (30).

[0051] The base station device (10), radio unit (21), extension unit (22), distributed end unit (23), and user terminal (30) can communicate with each other through a network (not shown). The network (not shown) refers to a connection structure that enables information exchange between each node, such as terminals and servers. Examples of such a network (not shown) include, but are not limited to, a 3GPP (3rd Generation Partnership Project) network, an LTE (Long Term Evolution) network, a 5G network, a WIMAX (World Interoperability for Microwave Access) network, the Internet, a LAN (Local Area Network), a Wireless LAN (Wireless Local Area Network), a WAN (Wide Area Network), a PAN (Personal Area Network), a Wi-Fi network, a Bluetooth network, a satellite broadcasting network, an analog broadcasting network, and a DMB (Digital Multimedia Broadcasting) network. In particular, in the case of the in-building system (1) disclosed herein, the base station device (10), radio unit (21), extension unit (22), and distributed end unit (23) may be connected to each other via wired communication, and the distributed end unit (23) and user terminal (30) may be connected to each other via wireless communication.

[0052] The user terminal (30) can be any type of wireless communication device, such as a smartphone, smartpad, tablet PC, PCS (Personal Communication System), GSM (Global System for Mobile communication), PDC (Personal Digital Cellular), PHS (Personal Handyphone System), PDA (Personal Digital Assistant), IMT (International Mobile Telecommunication)-2000, CDMA (Code Division Multiple Access)-2000, W-CDMA (W-Code Division Multiple Access), Wibro (Wireless Broadband Internet) terminal.

[0053] An in-building system (1) according to one embodiment of the present invention may include a base station device (10), a terminal (user terminal; 30) connected to the base station device (10) so as to be able to communicate with the base station device (10) via a radio unit (21), and a radio unit (21) that transmits an uplink signal to the base station device (10) or transmits a downlink signal from the base station device (10).

[0054] A radio unit (21) according to one embodiment of the present invention may be located between a base station device (10) and a user terminal (30) to transmit or relay signals. Additionally, the in-building system (1) may include an extension unit (22) that transmits signals between the radio unit (21) and a distributed termination unit (23). Meanwhile, in the description of the embodiment of the present invention, the extension unit (22) may be referred to as a Hub Unit (HU), and the distributed termination unit (23) may be referred to as a Service Unit (SU).

[0055] Below, the multi-carrier-based common operation function of the radio unit (21) for multiple operators will be described in detail with reference to FIGS. 2a and 2b.

[0056] FIGS. 2a and 2b are conceptual diagrams illustrating the common operation functions of multiple operators based on a multi-carrier in-building system according to one embodiment of the present invention.

[0057] Specifically, FIG. 2a (a) is a diagram showing the structure of an in-building system (1) having a radio unit (21) that can be jointly used for two base station devices (10a and 10b) corresponding to each of two different operators (communication operators, vendors), and FIG. 2b (a) is a diagram showing the structure of an in-building system (1) having a radio unit (21) that can be jointly used for four base station devices (10a, 10b, 10c, 10d) corresponding to each of four different operators (communication operators, vendors).

[0058] In addition, Figure 2a (b) and Figure 2b (b) are diagrams showing frequency bands that are separately allocated in correspondence with each operator signal.

[0059] Referring to FIGS. 2a and 2b, a radio unit (21) of an in-building system (1) according to one embodiment of the present invention is individually connected to a plurality of base station devices (10) corresponding to each of multiple operators and is equipped with a plurality of cables (e.g., optical cables, etc.) for transmitting operator signals from each of the plurality of base station devices (10) so as to be able to receive at least one operator signal from each of the plurality of base station devices (10), and can be individually connected to the plurality of base station devices (10) in an eCPRI manner.

[0060] Meanwhile, in the description of the embodiment of the present invention, the operator signal corresponding to each communication operator may be a signal assigned a mutually distinct frequency band corresponding to each of the multiple operators, and the radio unit (21) may configure a communication frame for at least one distributed end unit (23) placed in an in-building environment where the in-building system (1) is built, and transmit the operator signal received from at least one base station device (10) to the distributed end unit (23), and may be equipped with a digital filter that selectively turns on and off the payload of each of the multiple operators for a predefined communication frame depending on whether a specific operator signal is received.

[0061] In this regard, referring to the upper right illustration in FIG. 2a (a) and FIG. 2b (a), the radio unit (21) can determine the payload allocation pattern for a communication frame for transmitting a carrier signal based on the number of multiple base station devices (10) connected to the radio unit (21). In other words, the location of the payload for each carrier can be predetermined in the communication frame configured by the radio unit (21).

[0062] More specifically, as shown in FIG. 2b, in the case of a form (FR1) where four operators share a radio unit (21), a communication frame containing a total of 16 payload blocks (4 x 4) can be defined for each operator with a predetermined band (e.g., 100 MHz), and as shown in FIG. 2a, in the case of a form (FR2) where two operators share a radio unit (21), each operator supports up to 2 x 2 MIMO with a predetermined band (e.g., 400 MHz), so that the entire band (e.g., 800 MHz) of the two operators communicates in 2 x 2, thereby enabling the use of the same frequency band as the four-operator shared structure (FR1).

[0063] In other words, the four-operator common structure (FR1) and two-operator common structure (FR2) of the radio unit (21) can be operated by applying payload allocation on the same communication frame in different ways.

[0064] Additionally, the radio unit (21) may be equipped with a digital filter that selectively turns on and off each payload of a predefined multiple operators for a communication frame depending on whether an operator signal is received from each of the base station devices (10).

[0065] More specifically, the radio unit (21) can control the output signal transmitted to the distributed termination unit (23) by distinguishing the digital filters provided for the FPGA by each operator and turning on / off each filter switch of the digital filter. For example, when a specific operator signal is received from the base station device (10), the radio unit (21) can turn on the filter switch of the digital filter of the operator so that the output signal is transmitted so that the payload corresponding to the operator is transmitted, and when a specific operator signal is not received from the base station device (10), it can turn off the filter switch of the digital filter of the operator so that the payload corresponding to the operator is not transmitted.

[0066] According to one embodiment of the present invention, a radio unit (21) can generate an index table corresponding to a distribution path for a plurality of distributed terminal units (23) (in other words, a physical wire path to reach each of the plurality of distributed terminal units (23) from the radio unit (21)) based on an in-building wired environment including the number of extension units (22) and distributed terminal units (23) installed in the in-building system (1), the connection relationship (wired path) between the radio unit (21) and the extension unit (22), and the connection relationship (wired path) between the extension unit (22) and the distributed terminal unit (23).

[0067] More specifically, in the description of the embodiment of the present invention, the index table may refer to information for matching a beam ID and a distributed termination unit (23) using beamforming information obtained from a base station device (10), or information for mutually matching a beam ID and a distributed termination unit (23) included in the beamforming information transmitted from the base station device (10).

[0068] Additionally, the radio unit (21) can transmit an index table generated based on a wired path to reach a distributed terminal unit (23) in an in-building environment where the in-building system (1) is established to a base station device (10). This index table is initially generated during the initial installation (configuration) of the radio unit (21) and transmitted to the base station device (10), and can be updated in each slot unit by taking into account changes in the in-building environment.

[0069] In addition, the base station device (10), having received an index table from the radio unit (21), performs communication to transmit and receive signals via the radio unit (21) and a terminal (30) connected to a specific distributed end unit (23) among a plurality of distributed end units (23) based on the received index table. This allows the base station device (10) to smoothly perform communication in which each antenna provided in the distributed end unit (23) is independently activated using an index table that reflects the distributed wired path, without directly identifying information about the physical state of the in-building wired environment in which the in-building system (1) is constructed.

[0070] In this regard, FIG. 3 is a drawing for explaining beamforming technology according to one embodiment of the present invention.

[0071] Referring to FIG. 3, the base station device (10) transmits and receives radio waves wirelessly with the user terminal (30), and can use beamforming technology to establish an independent path between the base station device (10) and the user terminal (30).

[0072] In 5G networks using high frequencies in the millimeter wave band, beamforming technology is used to overcome the high path loss of high-frequency signals. Considering the narrow coverage characteristics of the beam, a beam-alignment process is required to find a beam angle that is suitable for the base station device (10) and the user terminal (30) in order to exchange data with each other. Specifically, to align the beam between the base station device (10) and the user terminal (30), the base station device (10) can transmit the signal of the SSB (Synchronization Signal Block) by beamforming the beam direction sequentially by a predetermined angle in one direction. Transmitting or receiving signals while rotating the beam direction by a predetermined angle in this way is called beam-sweeping or beam-scanning. Here, beam-sweeping refers to the action viewed from the side of the base station device (10), and beam-scanning refers to the action viewed from the side of the receiver.

[0073] For example, if a base station device (10) can have n beam directions, the base station device (10) can transmit signals such as SSB while sweeping the directions to be supported for each of the n beam directions. At this time, at least one beam can be grouped, and in this case, signals such as SSB can be transmitted for each beam group.

[0074] Synchronization Signal Blocks (SSBs) transmitted in the same direction may have multiple SSBs within a cell. When multiple SSBs exist, an SSB index may be used to distinguish each SSB. For example, when SSBs are transmitted in eight beam directions from a single base station device (10), eight SSB indices with different beam directions, such as SSB0 to SSB7, may be transmitted.

[0075] Meanwhile, although the above-described FIG. 1 is illustrated as having a radio unit (21) and an extension unit (22) connected in a 1:8 ratio and each extension unit (22) and a distributed termination unit (23) connected in a 1:16 ratio, this is not limited thereto, and the connection relationship between the radio unit (21) and the extension unit (22), the connection relationship between the extension unit (22) and the distributed termination unit (23), and the arrangement of the extension unit (22) can be varied according to the characteristics of the in-building environment in which the in-building system (1) is implemented. For example, according to an embodiment of the present invention, when a plurality of distributed termination units (23) are multiplely connected in a cascade form, the extension unit (22) and the distributed termination unit (23) may be connected in a 1:32 ratio.

[0076] At this time, when the user terminal (30) is powered on or intends to connect to a new cell, it can synchronize with the base station device (10) by using SSB information to determine the time and frequency parameters required to perform the transmission of downlink signals and uplink signals at an accurate time, and at this time, the user terminal (30) can obtain information such as beam ID (identity) from the SSB information.

[0077] FIG. 4 is a diagram showing beamforming information and distributed termination units that match each other according to one embodiment of the present invention.

[0078] Referring to FIG. 4, a radio unit (21) according to one embodiment of the present invention can match a beam ID and a distributed termination unit (23) using beamforming information obtainable from a base station device (10), and generate an index table that reflects the matching result.

[0079] Specifically, the radio unit (21) can use beamforming information transmitted from the base station device (10) to match a beam ID extracted therefrom with at least one of a plurality of distributed end units (23), and relay a signal between a user terminal (30) connected to the matched distributed end unit (23) and the base station device (10) to create an index table for connecting so that communication is possible.

[0080] At this time, the radio unit (21) enables only the distributed end unit (23) matched by the radio unit (21) to communicate with the base station device (10), thereby resolving the uplink noise problem for the base station device (10) that may occur when multiple distributed end units (23) communicate simultaneously.

[0081] FIG. 5 is a diagram showing the connection relationship between an in-building radio unit and a distributed termination unit according to one embodiment of the present invention.

[0082] Referring to FIG. 5, the radio unit (21) can distribute the communication path with the base station device (10) by matching a beam ID extracted using beamforming information transmitted from the base station device (10) with a distributed termination unit (23). Preferably, when the radio unit (21) matches the beam ID with the distributed termination unit (23), it can operate by dividing the time so that multiple distributed termination units (23) are not matched simultaneously, thereby matching the beam ID with the distributed termination unit (23) one-to-one according to a predetermined period. For example, referring to FIG. 5, the radio unit (21) can match different beam IDs to the first distributed termination unit (231) and the second distributed termination unit (232) to assign a distributed path to each of the first distributed termination unit (231) and the second distributed termination unit (232).

[0083] FIG. 6 is a diagram exemplarily showing the matching results of another beam ID and a distributed termination unit in one embodiment of the present invention.

[0084] Referring to FIG. 6, for example, the radio unit (21) can create an index table by matching beam ID #1 with distributed termination unit #1 at T1, beam ID #2 with distributed termination unit #2 at T2, and beam ID #n with distributed termination unit #n at Tn, according to a predetermined period T.

[0085] That is, the radio unit (21) can time-divide the uplink section or the downlink section at a predetermined interval, and the radio unit (21) can prevent two or more distributed end units (23) from being matched simultaneously in each time-divided section, and each distributed end unit (23) can operate so that the communication path with the base station device (10) via the radio unit (21) is opened only when it is matched.

[0086] Meanwhile, the in-building system (1) disclosed herein may include a radio unit (O-RU; O-RAN Radio Unit) (21) connected to communicate with an O-RAN (Open Radio Access Network Alliance)-based base station device (10), and a distributed end unit (FEU; Front-End Unit) (230) connected to communicate with a user terminal (30).

[0087] The radio unit (21) is connected to communicate with the base station device (10) and can relay the signal when communicating between the user terminal (30) connected to the radio unit (21) and the base station device (10).

[0088] At this time, the radio unit (21) can be connected to the base station device (10), specifically the distributed unit (DU) (12), via a wired connection (e.g., an optical cable) rather than a wireless connection.

[0089] In a 5G wireless access network, due to the increase in wireless speed and the increase in fronthaul capacity according to the MIMO system, the base station device (10) is implemented by separating it into a Central Unit (CU; Central Unit) (11) and a Distributed Unit (DU; Distributed Unit) (12), and the open base station structure having various structures is provided so that eight functional separation options can be selectively applied to the Central Unit (CU) (11) and the Distributed Unit (DU) (12).

[0090] In the O-RAN (Open-Radio Access Network), the physical layer is functionally separated so that the distributed base station unit (DU) (12) handles the High PHY, which is option 7, and the radio unit (21) handles the Low PHY, which is option 8, and the radio unit (21) and the distributed base station unit (DU) (12) can be connected to each other via a fronthaul interface.

[0091] That is, a radio unit (21) according to one embodiment of the present invention can support a front-haul interface with a base station device (10), among which a distributed base station unit (DU) (12).

[0092] Typically, the radio unit (21) has a wireless communication (RF) function and can relay a communication connection between a wirelessly connected user terminal (30) and a base station device (10). However, when the radio unit (21) according to one embodiment of the present invention is implemented for in-building use, the radio unit (21) does not have a wireless communication (RF) function, and the distributed terminal unit (23) has a wireless communication (RF) function and can be wirelessly connected to the user terminal (30).

[0093] That is, a radio unit (21) according to one embodiment of the present invention can indirectly relay communication signals between a base station device (10) and a user terminal (30) by using a distributed terminal unit (23) having a wireless communication function.

[0094] Additionally, the radio unit (21) may further include an extension unit (EU; Extension Unit) (220) for transmitting signals bidirectionally between one radio unit (21) and a plurality of distributed terminal units (23), acting as a concentrating device, i.e., a hub, as needed.

[0095] For example, in a building where the in-building system (1) disclosed herein is constructed, a radio unit (21) connected by a wire to a base station device (10) may be installed, and a plurality of distributed terminal units (23) connected to a user terminal (30) and an extension unit (22) for distributing communication signals between the radio unit (21) and the plurality of distributed terminal units (23) may also be provided. In this case, the distributed terminal units (23) may typically be installed on each floor when installed in the building, but are not limited thereto.

[0096] At this time, the distributed termination unit (23) according to one embodiment of the present invention may include an antenna for transmitting and receiving wireless signals with a user terminal (30), and as described above, the distributed termination unit (23) may communicate wirelessly (RF) with the user terminal (30) using the antenna. That is, the user terminal (30) may be relayed by a radio unit (21) including a distributed termination unit (23) having a wireless communication (RF) function, and may be connected to a base station device (10) for communication.

[0097] In addition, a radio unit (21) according to one embodiment of the present invention can distribute a communication path between a base station device (10) and a plurality of distributed end units (23) using beamforming information, and generate an index table corresponding to the distributed path information and transmit it to the base station device (10) (see FIG. 4).

[0098] That is, a radio unit (21) according to one embodiment of the present invention can match a beam ID with a distributed termination unit (23) using beamforming information received from a base station device (10).

[0099] When the radio unit (21) is for in-building use, the radio unit (21) does not need to perform beamforming, but the radio unit (21) according to one embodiment of the present invention can match the beam ID and the distributed termination unit (23) using the extracted SSB information obtained by pre-coding beamforming information transmitted from a base station, specifically a distributed base station unit (DU) (12).

[0100] Specifically, the radio unit (21) can match the extension unit (22) based on the SSB index obtained from the above SSB information, and can match the distributed termination unit (23) based on the CSI-RS index for more precise beamforming.

[0101] Here, the CSI-RS index belongs to the SSB index obtained from the extracted SSB information, and among the terms used in this specification, the beam ID may be a combination of the SSB index and the CSI-RS index belonging thereto.

[0102] A conventional radio unit (RU) with radio frequency (RF) capabilities can perform beamforming using a total of 8 SSB indices (SSB0 to SSB7) and a total of 16 CSI-RS indices (CSI-RS0 to CSI-RS15) in each beam, as illustrated in FIG. 4, for example.

[0103] A radio unit (21) according to one embodiment of the present invention does not have a wireless communication (RF) function, but can pre-code beamforming information transmitted from a base station device (10) and, if the extracted SSB index is SSB3 and its CSI-RS index is CSI-RS0, can match the distributed termination unit of reference numeral 233. Likewise, if the SSB index extracted from the beamforming information transmitted from the base station device (10) by the radio unit (21) is SSB3 and the CSI-RS index is CSI-RS1, it can match the distributed termination unit of reference numeral 234.

[0104] Here, since the SSB index obtained from the beamforming information of the radio unit (21) is SSB3, the extension unit of reference numeral 223 corresponding to SSB3 among the multiple extension units (22) can be matched, and the distributed termination unit of reference numeral 233 and the distributed termination unit of reference numeral 234 can be connected to communicate with the extension unit of reference numeral 223 according to the same SBS index.

[0105] That is, a radio unit (21) according to one embodiment of the present invention can match one distribution termination unit (23) to one CSI-RS index and one extension unit (22) to one SSB index.

[0106] In the case where a radio unit (21) according to one embodiment of the present invention matches a beam ID with a distributed termination unit (23), only the communication signal through the matched distributed termination unit (23) can be transmitted and received with the base station device (10).

[0107] Accordingly, communication signals from a non-matched distributed end unit (23) that are not matched by the radio unit (21) may not be relayed by the radio unit (21), and accordingly, uplink noise transmitted from the non-matched distributed end unit (23) may be blocked from being transmitted to the base station device (10).

[0108] Distributed end units (23) that are not matched due to the absence of a distributed end unit (23) that is not in its own time-division segment or a connected user terminal (30), etc., can be deactivated, and at this time, the communication path between the unmatched distributed end unit (23) and the radio unit (21) can be switched off. Therefore, even if signals transmitted from multiple distributed end units (23) are aggregated and transmitted to the base station device (10), the noise from the unmatched distributed end unit (23) is not superimposed on the uplink signal transmitted from the matched distributed end unit (23). Consequently, even if the number of distributed end units (23) connected to the radio unit (21) increases, the problem of the noise figure (NF) of the signal transmitted to the base station device (10) through the radio unit (21) increasing accordingly does not occur.

[0109] Meanwhile, a radio unit (21) according to a preferred embodiment of the present invention can perform precoding of beamforming information transmitted from a base station device (10) according to a predetermined period.

[0110] Typically, when beam-sweeping or beam-scanning is performed in multiple beam directions, SSB information is transmitted in a time-divided manner according to a predetermined period. Therefore, it is desirable for the radio unit (21) according to one embodiment of the present invention to perform precoding according to a predetermined period in accordance with this, and the period may be the generation period of C-plane data, OFDM symbol unit, etc., and may be, for example, about 1 ms.

[0111] In addition, the radio unit (21) according to a preferred embodiment of the present invention can precode only the C-plane data of the fronthall interface.

[0112] As described above, the distributed base station unit (DU) (12) and the radio unit (21) of the base station device (10) can be connected via a fronthall interface. In this case, it is desirable for the radio unit (21) to precode only the C-plane data, excluding the U-plane data, among the C-plane data as a protocol for transmitting control signals, the U-plane data as a protocol for transmitting user data, and the S-plane data as a protocol for synchronization, in order to improve processing speed and processing efficiency.

[0113] That is, it is preferable for the radio unit (21) to precode only the C-plane data to extract beam ID information, etc.

[0114] Figure 7 is a diagram illustrating the noise of the uplink signal for a base station.

[0115] Referring to FIG. 7, when there is one Front-End Unit (FEU) of the radio unit (21), the communication signal containing noise is as shown in FIG. 7 (a); when there are two Front-End Units, the communication signal containing noise is as shown in FIG. 7 (b); and when there are more than n Front-End Units, the communication signal containing noise is as shown in FIG. 7 (c).

[0116] In other words, there is a problem that the noise figure (NF) increases as the number of distributed termination units increases. This is because the radio unit (21) is not a noise-free device, so the noise figure (NF) can increase as the number increases.

[0117] Therefore, when a connection of multiple distributed end units is required to a single base station device (10), the problem of uplink noise that may occur can be resolved by using a radio unit (21) through the in-building system (1) disclosed herein to replace the logical path for beamforming with a wired path in an in-building environment, thereby ensuring that only one distributed end unit is activated in one layer.

[0118] In addition, the in-building system (1) disclosed herein has the advantage of preventing interference between distributed end units by distributing the communication paths for multiple distributed end units operating in an in-building environment using beamforming information, as well as reducing the burden on the downlink amplifier and reducing power consumption.

[0119] FIG. 8 is a schematic diagram of a base station device of an in-building solution using an index table corresponding to a distributed path utilizing a beamforming element according to one embodiment of the present invention.

[0120] Referring to FIG. 8, the base station device (10) may include a reference information acquisition unit (110) and a communication execution unit (120).

[0121] The reference information acquisition unit (110) can acquire an index table corresponding to a distribution path for a plurality of distributed terminal units (23) that are placed in an in-building environment where the in-building system (1) is built from the radio unit (21).

[0122] The communication execution unit (120) can transmit and receive signals via a radio unit (21) and a user terminal (30) connected to a predetermined distributed terminal among a plurality of distributed terminal units (23) based on an acquired index table.

[0123] Figure 9 is a schematic diagram of a radio unit of an in-building solution using an index table corresponding to a distributed path utilizing beamforming elements.

[0124] Referring to FIG. 9, the radio unit (21) may include a base station connection part (210), a matching part (220), a communication relay part (230), and a filter part (240).

[0125] The base station connection unit (210) may be individually connected to a plurality of base station devices (10) corresponding to each of the multiple operators and configured to receive at least one operator signal from each of the plurality of base station devices (10).

[0126] According to one embodiment of the present invention, the base station connection unit (210) may be individually connected to up to four different base station devices (e.g., individually connected to two or four base station devices (10)), and each operator signal for each base station device (10) may be a signal assigned a mutually distinct frequency band corresponding to each of the multiple operators.

[0127] For example, the base station connection part (210) may be provided with a plurality of cables for receiving operator signals from each of the plurality of base station devices (10).

[0128] Additionally, the base station connection unit (210) can be connected to each of the multiple base station devices (10) using the eCPRI method.

[0129] The matching unit (220) can generate an index table corresponding to the distribution path for a plurality of distributed terminal units (23).

[0130] The communication relay unit (230) can transmit the index table generated by the matching unit (220) to the base station device (10).

[0131] Additionally, the communication relay unit (230) can transmit a signal received from the base station device (10) to a predetermined distributed end unit based on a pre-generated index table among a plurality of distributed end units (23) in an in-building environment, and transmit a signal received from a terminal connected to the predetermined distributed end unit to the base station device (10).

[0132] Additionally, the communication relay unit (230) can configure a communication frame for at least one distributed end unit (23) deployed in an in-building environment. Specifically, the communication relay unit (230) can determine an allocation pattern of the payload for the communication frame based on the number of multiple base station devices.

[0133] Additionally, the communication relay unit (230) can transmit a carrier signal transmitted from the base station device (10) to the distributed end unit (23) through a communication frame configured for the distributed end unit (23).

[0134] The filter unit (240) may be equipped with a digital filter that selectively turns on and off each payload of a predefined multiple operators for a communication frame for a distributed terminal unit (23) depending on whether an operator signal transmitted from the base station device (10) is received.

[0135] Specifically, the filter unit (240) can control the digital filter so that the output signal of the corresponding frequency band corresponding to the operator signal received from the base station device (10) received through the base station connection unit (210) is output through the distributed termination unit (23).

[0136] Below, based on the details described above, we will briefly examine the operation flow of the present invention.

[0137] FIG. 10 is a flowchart of the operation method of an in-building radio unit of an in-building solution that provides a common operation function for multiple operators based on a multi-carrier according to one embodiment of the present invention.

[0138] The method of driving an in-building radio unit of an in-building solution providing common operational functions for multiple carriers based on a multi-carrier system, as illustrated in FIG. 10, can be performed by the radio unit (21) described above. Therefore, even if the details are omitted below, the description of the radio unit (21) can be applied in the same way to the description of the method of driving an in-building radio unit of an in-building solution providing common operational functions for multiple carriers based on a multi-carrier system.

[0139] Referring to FIG. 10, in step S11, the communication relay unit (230) can be configured for at least one distributed end unit (23) placed in an in-building environment, and the location of the payload corresponding to each of the multiple operators according to the plurality of base station devices (10) can be predefined in the communication frame.

[0140] Next, in step S12, the base station connection unit (210) can receive at least one operator signal from each of the multiple base station devices (10) corresponding to each of the multiple operators.

[0141] Next, in step S13, the filter unit (240) can selectively turn on and off each payload of a predefined communication frame depending on whether the operator signal in step S12 is received.

[0142] In the description above, steps S11 through S13 may be further divided into additional steps or combined into fewer steps according to an embodiment of the present invention. Additionally, some steps may be omitted as necessary, and the order between steps may be changed.

[0143] A method for driving an in-building radio unit of an in-building solution providing common operational functions for multiple operators based on a multi-carrier approach according to one embodiment of the present invention may be implemented in the form of program instructions that can be executed through various computer means and recorded on a computer-readable medium. The computer-readable medium may include program instructions, data files, data structures, etc., either individually or in combination. The program instructions recorded on the medium may be those specifically designed and configured for the present invention, or may be those known and available to those skilled in the art of computer software. Examples of computer-readable recording media include magnetic media such as hard disks, floppy disks, and magnetic tapes; optical recording media such as CD-ROMs and DVDs; magneto-optical media such as floptical disks; and hardware devices specifically configured to store and execute program instructions, such as ROM, RAM, and flash memory. Examples of program instructions include machine code, such as that generated by a compiler, as well as high-level language code that can be executed by a computer using an interpreter, etc. The above-described hardware device may be configured to operate as one or more software modules to perform the operation of the present invention, and vice versa.

[0144] In addition, the method of operating an in-building radio unit of an in-building solution that provides the aforementioned multi-carrier-based common operation function for multiple operators can also be implemented in the form of a computer program or application executed by a computer stored on a recording medium.

[0145] The foregoing description of the present invention is for illustrative purposes only, and those skilled in the art will understand that other specific forms can be easily modified without altering the technical concept or essential features of the present invention. Therefore, the embodiments described above should be understood as illustrative in all respects and not restrictive. For example, each component described as a single unit may be implemented in a distributed manner, and components described as distributed may likewise be implemented in a combined form.

[0146] The scope of the present invention is defined by the claims set forth below rather than by the detailed description above, and all modifications or variations derived from the meaning and scope of the claims and the concept of equivalents thereof should be interpreted as being included within the scope of the present invention. Explanation of the symbols

[0147] 1: In-building system 10: Base station device 110: Reference Information Acquisition Unit 120: Communication Execution Unit 11: Central Unit, CU 12: Distributed Unit, DU 21: Radio Unit (RU) 210: Base station connection 220: Matching section 230: Communications Relay Department 240: Filter section 220: Extension Unit 230: Distributed Termination Unit 30: User terminal

Claims

Claim 1 A radio unit of an in-building solution providing common operational functions for multiple operators based on a multi-carrier, comprising: a base station connection unit configured to be individually connected to a plurality of base station devices corresponding to each of the multiple operators and capable of receiving at least one operator signal from each of the plurality of base station devices; a communication relay unit configured to form a communication frame for at least one distributed end unit deployed in an in-building environment and to transmit the operator signal to the distributed end unit through the communication frame; and a filter unit comprising a digital filter that selectively turns on or off a predefined payload of each of the multiple operators for the communication frame depending on whether the operator signal is received, wherein the communication relay unit determines an allocation pattern of the payload for the communication frame based on the number of the plurality of base station devices so that the location of the payload for each operator is predetermined on the same communication frame, thereby enabling the use of the same frequency band even when the number of the plurality of base station devices is different. Claim 2 A radio unit according to claim 1, wherein the base station connection part comprises a plurality of cables for receiving the operator signal from each of the plurality of base station devices. Claim 3 In paragraph 1, the radio unit, wherein the base station connection part is connected to each of the plurality of base station devices in an eCPRI manner. Claim 4 A radio unit according to claim 1, wherein the above-mentioned operator signal is assigned a mutually distinct frequency band corresponding to each of the above-mentioned multiple operators. Claim 5 A radio unit according to paragraph 4, wherein the filter unit controls the digital filter so that an output signal of the frequency band corresponding to the operator signal received through the base station connection unit is output through the distributed termination unit. Claim 6 delete Claim 7 A radio unit according to claim 1, wherein the base station connection part is individually connected to up to four different base station devices. Claim 8 An in-building solution providing a common operation function for multiple carriers based on a multi-carrier, comprising: a radio unit individually connected to a plurality of base station devices corresponding to each of the multiple carriers, receiving at least one carrier signal from each of the plurality of base station devices, and transmitting the carrier signal to a distributed end unit through a predefined communication frame; and a distributed end unit that outputs an output signal corresponding to the carrier signal received from the radio unit and is allocated such that the frequency bands corresponding to each of the multiple carriers are mutually distinguishable, wherein the radio unit determines an allocation pattern of the payload for the communication frame based on the number of the plurality of base station devices so that the location of the payload for each carrier is predetermined on the same communication frame, thereby enabling the use of the same frequency band even when the number of the plurality of base station devices is different. Claim 9 A driving method for an in-building radio unit of an in-building solution providing common operating functions for multiple operators based on a multi-carrier, comprising: a step of configuring a communication frame defined for at least one distributed end unit deployed in an in-building environment, wherein the location of a payload corresponding to each of the multiple operators is predetermined; a step of receiving at least one operator signal from each of a plurality of base station devices corresponding to each of the multiple operators; and a step of selectively turning on or off each payload of the communication frame according to whether the operator signal is received, wherein the step of configuring the communication frame is characterized by determining an allocation pattern of the payload for the communication frame based on the number of the plurality of base station devices so that the location of the payload for each operator is predetermined on the same communication frame, thereby enabling the use of the same frequency band even when the number of the plurality of base station devices is different.

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