[go: up one dir, main page]

WO2024166765A1 - Système de relais de communication, procédé de relais de communication, et programme - Google Patents

Système de relais de communication, procédé de relais de communication, et programme Download PDF

Info

Publication number
WO2024166765A1
WO2024166765A1 PCT/JP2024/003084 JP2024003084W WO2024166765A1 WO 2024166765 A1 WO2024166765 A1 WO 2024166765A1 JP 2024003084 W JP2024003084 W JP 2024003084W WO 2024166765 A1 WO2024166765 A1 WO 2024166765A1
Authority
WO
WIPO (PCT)
Prior art keywords
mobile station
unit
array antenna
frequency band
communication
Prior art date
Application number
PCT/JP2024/003084
Other languages
English (en)
Japanese (ja)
Inventor
敏則 土井
Original Assignee
株式会社 東芝
東芝インフラシステムズ株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 株式会社 東芝, 東芝インフラシステムズ株式会社 filed Critical 株式会社 東芝
Publication of WO2024166765A1 publication Critical patent/WO2024166765A1/fr

Links

Images

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W16/00—Network planning, e.g. coverage or traffic planning tools; Network deployment, e.g. resource partitioning or cells structures
    • H04W16/24—Cell structures
    • H04W16/26—Cell enhancers or enhancement, e.g. for tunnels, building shadow
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W16/00—Network planning, e.g. coverage or traffic planning tools; Network deployment, e.g. resource partitioning or cells structures
    • H04W16/24—Cell structures
    • H04W16/28—Cell structures using beam steering
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W64/00—Locating users or terminals or network equipment for network management purposes, e.g. mobility management

Definitions

  • Embodiments of the present invention relate to a communication relay system, a communication relay method, and a program.
  • 5G fifth generation mobile communications system
  • beamforming This is a function that expands the area where wireless communication is possible (coverage area) and increases cell capacity by communicating with multiple users simultaneously by coordinating the operation of multiple antenna elements on a single antenna to form a beam of radio waves in any direction. This is generally achieved in combination with a massive multi-element antenna (Massive MIMO).
  • Mass MIMO massive multi-element antenna
  • the Distributed Antenna System has been used in mobile communication systems as a coverage area measure that enables wireless communication indoors.
  • the DAS system relays and transmits signals related to communication between mobile stations and base stations, and consists of a parent unit and multiple child units that are distributed.
  • the parent unit distributes the signal from one base station to multiple child units, and each child unit outputs the same downlink signal from its respective antenna, creating an area as a single cell.
  • C-Plane (Control Plane) control signals use the LTE band for communication between the terminal, DAS and base station, completing RACH processing (RRC connection) with the terminal, and the subsequent U-Plane (User Plane) data signals are used in the NR band; however, there was no way to control the beams in the LTE and NR bands to ensure both a high connection rate and improved throughput.
  • the embodiment of the present invention has been made in consideration of the above circumstances, and aims to provide a communication relay system, a communication relay method, and a program that can ensure a connection rate and improve throughput by controlling beams using the LTE band and the NR band in a DAS system.
  • the communication relay system has a parent unit capable of transmitting and receiving signals to and from a base station, and a child unit that transmits signals between the parent unit and wirelessly communicates with a mobile station.
  • the child unit includes a plurality of array antennas including a plurality of antenna elements, a switching unit that switches the array antenna connected to the child unit according to a frequency band, a forming unit that detects a mobile station present in an area capable of wireless communication with the child unit by forming an area omnidirectionally using radio waves output from a first array antenna in a first frequency band, and transmits a control signal between the mobile station and the child unit, a detection unit that detects position information of the mobile station by controlling the directivity of radio waves output from a second array antenna in a second frequency band, and a data communication unit that controls the directivity of radio waves output from a third array antenna in a third frequency band based on the position information, and transmits a data signal between the mobile station and the child unit.
  • FIG. 1 is a diagram showing an example of a configuration of a mobile communication system including a communication relay system according to an embodiment.
  • FIG. 2 is a block diagram showing an example of the configuration of a master unit of the communication relay system according to the embodiment.
  • FIG. 3 is a block diagram illustrating an example of the configuration of a slave unit of the communication relay system according to the embodiment.
  • FIG. 4 is a block diagram illustrating an example of the configuration of a wireless communication unit of a slave unit of the communication relay system according to the embodiment.
  • FIG. 5 is a diagram for explaining an example of beamforming by a slave unit of the communication relay system according to the embodiment.
  • FIG. 6 is a diagram for explaining an example of beamforming by a slave unit of the communication relay system according to the embodiment.
  • FIG. 1 is a diagram showing an example of a configuration of a mobile communication system including a communication relay system according to an embodiment.
  • FIG. 2 is a block diagram showing an example of the configuration of a master unit of the communication relay system according
  • FIG. 7 is a diagram for explaining an example of beamforming by a slave unit of the communication relay system according to the embodiment.
  • FIG. 8 is a diagram for explaining an example of a high-speed search for a mobile station by a slave unit of the communication relay system according to the embodiment.
  • FIG. 9 is a diagram for explaining an example of a slow search for a mobile station by a slave unit of the communication relay system according to the embodiment.
  • FIG. 10 is a diagram for explaining an example of a tracking search of a mobile station by a slave unit of the communication relay system according to the embodiment.
  • FIG. 11 is a diagram for explaining an example of a tracking search of a mobile station by a slave unit of the communication relay system according to the embodiment.
  • FIG. 12 is a diagram for explaining an example of a search result of a mobile station by a slave unit of the communication relay system according to the embodiment.
  • FIG. 13 is a diagram illustrating an example of processing of the array antenna of the communication relay system according to the embodiment.
  • FIG. 14 is a diagram illustrating an example of processing of the array antenna of the communication relay system according to the embodiment.
  • FIG. 15 is a diagram illustrating an example of processing of the array antenna of the communication relay system according to the embodiment.
  • FIG. 16 is a diagram showing an example of a time series of terminals and base stations and a time series of an array antenna in the communication relay system according to the embodiment.
  • FIG. 17 is a diagram illustrating an example of beam groups in an array antenna of a communication relay system according to an embodiment.
  • FIG. 1 shows a part of a fifth generation mobile communication system, known as 5G.
  • This mobile communication system comprises a 5GC (5th Generation Core network), which is the core network of 5G, an EPC (Evolved Packet Core), which is the core network of LTE, and a radio access network RAN.
  • the communication relay system according to this embodiment is included in the radio access network RAN.
  • the 5G core network 5GC and the LTE core network EPC control the radio access network RAN, bundle traffic and exchange with external networks (the Internet, external telephone networks, etc.), and each has a core device at its heart.
  • the core device performs, for example, authentication and security management, session management, policy control, packet forwarding, etc.
  • the radio access network RAN comprises multiple base station devices (for example, gNB (gNodeB) 1, gNB 2, and eNB (eNodeB) in FIG. 1).
  • the base station devices gNB 1, gNB 2, and eNB are controlled by a core device, and each forms an area (so-called a cell or coverage area) in which wireless communication with a mobile station UE (User Equipment) is possible.
  • the base station device gNB1 wirelessly communicates with mobile stations UE within the coverage area through an antenna device AN installed on the roof of a building or on a dedicated tower, and connects the mobile stations UE to the 5G core network 5GC through the core device.
  • the base station device gNB1 also performs beamforming using Massive MIMO, which controls the phase of signals in multiple antenna elements on the antenna device AN, contributing to increased communication capacity, etc.
  • the base station device gNB2 has the same functions as the base station device gNB1, but communicates wirelessly with the mobile station UE through a distributed antenna system DAS instead of the antenna device AN, and connects the mobile station UE to the 5G core network 5GC through the core device.
  • the base station device eNB communicates wirelessly with the mobile station UE through the distributed antenna system DAS, and connects the mobile station UE to the LTE core network EPC through the core device.
  • the distributed antenna system DAS is an example of a communication relay system related to this embodiment, and is used to form a coverage area that is relatively small compared to the antenna device AN in special locations (for example, inside buildings, underground shopping malls, and other structures, depopulated or overpopulated areas, areas where it is difficult or limited to construct towers, temporary locations for the antenna device AN such as event venues, etc.), and as shown in Figure 1, it comprises a master unit MU (Master Unit), remote units RU (Remote Units) 1 to RU3, and antennas AN1 to AN3.
  • Master Unit Master Unit
  • remote units RU Remote Units
  • the distributed antenna system DAS is shown within the radio access network RAN, but it is not necessarily controlled by the 5G core network 5GC, the LTE core network EPC, the base station device gNB2, or the base station device eNB, and the distributed antenna system DAS can autonomously control beamforming and other operations.
  • the master unit MU controls all the parts of the distributed antenna system DAS and is connected to the base station device gNB2 (e.g., the base station device of telecommunications carrier A) shown in FIG. 1 by a coaxial cable (e.g., a 4x4 MIMO configuration of four 100 MHz bands), and is similarly connected to the base station devices gNB2 of other telecommunications carriers B and C (not shown) by other coaxial cables.
  • the master unit MU is connected to each of the gNodeBs of multiple telecommunications carriers A, B, and C by coaxial cables.
  • the master unit MU is connected to each of the eNodeBs of multiple telecommunications carriers A, B, and C by coaxial cables.
  • the master unit MU also functions as a communications relay device by connecting the mobile station UE, which is connected via antennas AN1 to AN3 and their corresponding slave units RU1 to RU3, to the base station devices gNB2 and eNB of the telecommunications carrier to which the user of the mobile station UE subscribes.
  • Antennas AN1 to AN3 are connected one-to-one to their corresponding child units RU1 to RU3, each equipped with numerous antenna elements, and compatible with Massive MIMO, in which directivity is controlled (beamforming) by adjusting the phase of the transmitted RF signal and/or the received RF signal.
  • the antenna elements are arranged in four groups, each consisting of 4 x 4 elements (array antenna), and the directivity can be controlled for each group.
  • each of the antennas AN1 to AN3 will be described as performing beamforming to simultaneously form up to four beams corresponding to the above groups (array antennas) in any direction, and for the sake of simplicity, the parent unit MU, which will be described in detail later, will also be described as processing (relaying) up to four streams corresponding to the above four beams at the same time.
  • the number is not limited to a maximum of four, but may be three or less, or five or more. Also, the number of beams formed by each of the antennas AN1 to AN3 is not fixed, but may be dynamically changed by varying the number of antenna elements used, for example.
  • the slave units RU1 to RU3 are connected one-to-one to the corresponding antennas AN1 to AN3, and can also be connected to the master unit MU so as to be able to communicate with them via an optical communication line.
  • the slave units RU1 to RU3 can be connected to the master unit MU using a daisy chain method, or the slave units RU1 to RU3 can be connected directly to the master unit MU (star type, not shown).
  • Child unit RUn When we refer to them as “child unit RUn,” the explanation is common to all child units RU1 to RU3. In other words, "n" can be read as any of 1 to 3.
  • antenna ANn this may be described as “antenna ANn.”
  • antenna is connected to the slave unit RUn, and is one of antennas AN1 to AN3.
  • n can be read as any of 1 to 3
  • antenna ANn is connected to slave unit RUn.
  • the slave unit RUn is capable of performing beamforming by adjusting the phase of the antenna ANn, and by measuring the strength of the received signal and performing the beamforming, it can detect (search) the direction in which the mobile station UE is located, and can even track and communicate with the moving mobile station UE.
  • the slave RUn performs phase adjustment (beamforming) on the RF signal obtained by the antenna ANn.
  • the antenna ANn can simultaneously obtain received RF signals corresponding to up to four beams, and also supports the frequency bands of any of the three telecommunications carriers mentioned above.
  • the slave unit RUn then down-converts the received RF signal corresponding to each beam and demodulates it into four received signals corresponding to up to four beams at the same time.
  • the slave unit RUn then serially bundles the demodulated received signals, converts them from electrical signals to optical signals (modulates the optical carrier), and transmits them to the master unit MU via the optical communication line.
  • the stream contained in the received signals is referred to as the UL stream signal.
  • the slave unit RUn detects the optical signal addressed to itself (slave unit RUn) among the optical signals transmitted from the master unit MU through the optical communication line, converts the optical signal into an electrical signal, and simultaneously demodulates it into signals corresponding to up to four streams (hereinafter referred to as DL stream signals).
  • the slave unit RUn uses the DL stream signal to generate a transmission RF signal by modulating a carrier wave in a frequency band corresponding to the telecommunications carrier, and outputs this transmission RF signal to the antenna ANn to radiate it into space.
  • the antenna ANn is capable of beamforming, which forms a beam for each of up to four DL stream signals, and is also compatible with the frequency bands of any of the three telecommunications carriers described above.
  • Figure 2 shows an example of the configuration of the parent unit MU. That is, the parent unit MU comprises a port P, a control unit 100, a transmission unit 110, a UL (Up Link) signal processing unit 120, a DL (Down Link) signal processing unit 130, and a memory unit 140.
  • the parent unit MU comprises a port P, a control unit 100, a transmission unit 110, a UL (Up Link) signal processing unit 120, a DL (Down Link) signal processing unit 130, and a memory unit 140.
  • Port P accommodates multiple optical communication lines (e.g., 25 Gbit/s per line) from the outside and is connected to child unit RU1 via these optical communication lines, and is also connected internally to UL signal processing unit 120 and DL signal processing unit 130.
  • optical communication lines e.g., 25 Gbit/s per line
  • port P is essentially connected to child units RU2 and RU3, and is capable of communicating with any of child units RU1 to RU3 via optical signals (sending and receiving optical signals).
  • port P demultiplexes the optical signal sent from slave unit RU1, separates it into multiple optical signals, converts each optical signal into an electrical signal, demodulates it, and obtains multiple telecommunication signals.
  • These multiple telecommunication signals are received signals (i.e., UL stream signals) corresponding to each beam in slave units RU1 to RU3, and are output in parallel to UL signal processing unit 120.
  • port P functions as an information detection unit that detects information sent from the slave units RU1 to RU3 and contained in each received signal. For example, it monitors the received signal and detects a communication start request (PRACH) from the mobile station UE contained in the received signal, and detects the stream ID assigned to each received signal (UL stream signal).
  • PRACH communication start request
  • port P functions as an information detection unit to detect the identification information of the sender (one of the slave units RU1 to RU3) from the received signal, and for each slave unit RU1 to RU3, detects the identification information of the mobile station UE located within the coverage area, location information indicating the location of that mobile station UE within the coverage area (Beam Index, described later), and the carrier ID indicating the telecommunications carrier to which the user of that mobile station UE subscribes. These detection results are notified to the control unit 100.
  • port P receives a DL stream signal from DL signal processing unit 130.
  • Port P then adds identification information of the destination slave units RU1 to RU3 to the received DL stream signal, converts the signal from an electrical signal to an optical signal (modulates the optical carrier), multiplexes these optical signals, and transmits them to slave units RU1 to RU3 via the optical communication line.
  • the transmission unit 110 accommodates communication lines (coaxial cables) connected to the base station devices gNB2 and eNB of each of the telecommunications carriers A, B, and C, and communicates with the base station devices gNB2 and eNB of each of the carriers through these communication lines. Specifically, for the uplink, the transmission unit 110 transmits the UL signal input from the UL signal processing unit 120 to the base station devices gNB2 and eNB of the corresponding telecommunications carrier. On the other hand, for the downlink, the transmission unit 110 receives the DL stream signal transmitted from the base station devices gNB2 and eNB of each telecommunications carrier through the above communication lines, and outputs it to the DL signal processing unit 130.
  • communication lines coaxial cables
  • the UL signal processing unit 120 performs signal addition processing to add the received signals of each beam input from port P for each telecommunications carrier according to the control of the control unit 100, and outputs the UL signal to the transmission unit 110 for each telecommunications carrier.
  • the DL signal processing unit 130 performs multiplexing processing under the control of the control unit 100, multiplexing the DL stream signals of each carrier input from the transmission unit 110 and outputting them to port P.
  • the control unit 100 is a control center that controls each part of the parent unit MU and is equipped with a work memory (not shown) and a processor (not shown) that executes processing based on control programs and control data loaded into the work memory from the storage unit 140 (described later), thereby achieving various control functions.
  • the control unit 100 is an example of a switching unit, formation unit, detection unit, and data communication unit.
  • control unit 100 controls communication relay between the mobile station UE and the base station devices gNB2 and eNB via the child devices RU1 to RU3, and performs stream allocation control, beamforming control, array antenna switching control, etc. for the child devices RU1 to RU3 based on the detection results notified from port P and DL stream signals transmitted from the base station devices gNB2 and eNB.
  • Stream allocation control stores and manages (updates) information about handset units RU1 to RU3, including their capabilities (such as the number of streams they can handle) and the number of streams currently allocated, as well as mobile station information, including the location information of the mobile station UE, and makes a comprehensive decision based on this handset unit information and mobile station information to allocate streams to handset units RU1 to RU3.
  • Beamforming control also manages the usage (availability) of radio resources for each of the slave units RU1 to RU3, and controls multiple slave units to perform beamforming in cooperation with each other for mobile stations UE located in areas where the coverage areas of the slave units RU1 to RU3 overlap, depending on the usage of radio resources.
  • beamforming is performed so that slave unit RU1 and slave unit RU2 each transmit and/or receive signals to the mobile station UE.
  • beamforming is performed so that the slave unit RU2 transmits and/or receives to the mobile station UE.
  • Array antenna switching control controls the array antennas included in antenna ANn that processes the mobile station UE to be switched according to the frequency band. For the sake of explanation in this embodiment, it is assumed that there are four array antennas, and that array antennas AA1 to AA4 are included in antenna ANn.
  • the array antennas are switched so that array antenna AA1 and array antenna AA2 perform processing in the LTE band for the mobile station UE, and array antenna AA3 performs processing in the NR band (e.g., n78).
  • NR band e.g., n78
  • the storage unit 140 stores the control programs and control data used by the control unit 100, as well as the child device Beam Index map data 140a, etc.
  • the control programs and control data are pre-installed at the time of manufacture, and are also installed or updated through an external interface (not shown) during manufacturing setup, or by communicating with servers on the 5G core network 5GC and LTE core network EPC of core devices, etc.
  • the child unit Beam Index map data 140a is data used in beamforming control, and is a data table that compiles the Beam Index map data 240a stored in each of the child units RU1 to RU3 under the control of the parent unit MU. Details of the Beam Index map data 240a will be described later.
  • the child unit Beam Index map data 140a is map-like data that associates Beam Index with coordinates indicating the direction of each beam that child units RU1 to RU3 can respectively form, and among the beam directions included in this data, the beam directions in the parts where the coverage areas of child units RU1 to RU3 overlap (parts where beams overlap between child units) are given identification information (e.g., an overlap flag) to identify them as beam directions in the overlap area OA.
  • identification information e.g., an overlap flag
  • the slave unit RUn includes a control unit 200, a communication unit 210, a signal processing unit 220, a wireless communication unit 230, and a storage unit 240, and is connected to an antenna ANn.
  • the communication unit 210 transmits and receives optical communication signals to and from the parent unit MU via an optical communication line, and has at least two ports to accommodate it. It has a relay function as an optical communication repeater that amplifies an optical communication signal input via the optical communication line accommodated in one port and outputs it via the optical communication line accommodated in the other port, a branching and multiplexing function that branches and multiplexes optical communication signals to the optical communication line, and a modulation and demodulation function as a modulator and demodulator that converts between optical signals and electrical signals.
  • the modem has an optical/electrical conversion function that receives an optical signal through an optical communication line and performs optical/electrical conversion to obtain an electrical communication signal (DL stream signal), and an electrical/optical conversion function that performs electrical/optical conversion on an electrical communication signal (UL stream signal) input from the signal processing unit 220 described below to convert it into an optical communication signal and transmit it through the optical communication line.
  • DL stream signal an electrical communication signal
  • UL stream signal an electrical/optical conversion function that performs electrical/optical conversion on an electrical communication signal (UL stream signal) input from the signal processing unit 220 described below to convert it into an optical communication signal and transmit it through the optical communication line.
  • the signal processing unit 220 communicates with the base station device gNB2 and the base station device eNB in accordance with a specified communication protocol. For the downlink direction of the system (from the base station device to the child device), it demodulates and decodes the communication signal obtained by the communication unit 210, detects the DL stream signal addressed to the child device RUn based on the identification information that identifies the destination, and outputs it to the control unit 200.
  • the signal addressed to the base station device gNB2 and the base station device eNB provided by the control unit 200 is used to modulate the carrier wave to generate a UL stream signal, which is output to the communication unit 210.
  • identification information of the sender one of the child devices RU1 to RU3 is added to the UL stream signal by the signal processing unit 220 or the control unit 200.
  • the wireless communication unit 230 performs wireless communication with the mobile station UE through the antenna ANn, and adopts a wireless access method that complies with 5G and LTE. Therefore, even when communicating through the distributed antenna system DAS, the mobile station UE can perform wireless communication using the same wireless access method as when communicating with the base station device gNB1 through the antenna device AN shown in FIG. 1.
  • the wireless communication unit 230 also performs beamforming using massive MIMO, which controls the phase of signals (transmitted RF signals and/or received RF signals) in multiple antenna elements on the antenna ANn, according to instructions from the control unit 200.
  • the wireless communication unit 230 also measures the received signal strength (e.g., RSSI) from the mobile station UE, associates this measurement result with the identification information of the mobile station UE, and notifies the control unit 200. Also, since different communication carriers use different frequency bands, the wireless communication unit 230 detects the received signal strength for each of the frequency bands, i.e., for each communication carrier, and notifies the control unit 200 of the detection results.
  • RSSI received signal strength
  • the received signal strength for each telecommunications carrier in the wireless communication unit 230 can be detected, for example, by a configuration such as that shown in FIG. 4.
  • FIG. 4 the configuration related to the transmission and reception of wireless signals and modulation and demodulation is omitted, and a configuration for detecting the received signal strength for each telecommunications carrier as described above is shown.
  • the wireless communication unit 230 which is configured for this detection, includes a signal control unit 231, an output switch (SW) 232, a downstream hybrid circuit 233, a transmitting amplifier 234, a circulator 235, a receiving amplifier 236, an upstream hybrid circuit 237, a bandpass filter 238, and an RSSI detection unit 239.
  • SW output switch
  • the wireless communication unit 230 includes a signal control unit 231, an output switch (SW) 232, a downstream hybrid circuit 233, a transmitting amplifier 234, a circulator 235, a receiving amplifier 236, an upstream hybrid circuit 237, a bandpass filter 238, and an RSSI detection unit 239.
  • the signal control unit 231 separates the downlink radio frequency signal into the frequency bands used by each telecommunications carrier and outputs them to the output switch 232.
  • the output switch 232 is provided with an output switch for each telecommunications carrier, and the ON/OFF of the output switch is controlled by the signal control unit 231, making it possible to selectively output a signal for each telecommunications carrier (for each frequency band).
  • the downstream hybrid circuit 233 combines the signals input from the output switch 232 into one radio frequency signal and outputs it to the transmission amplifier 234.
  • the transmitting amplifier 234 amplifies the radio frequency signal input from the downstream hybrid circuit 233 and outputs it to the antenna ANn via the circulator 235. From the antenna ANn, the signal is radiated into space and transmitted to the mobile station UE.
  • the radio signal transmitted from the mobile station UE is received by the antenna ANn and then output to the receiving amplifier 236 via the circulator 235.
  • the receiving amplifier 236 performs high-frequency amplification on the radio frequency signal received by the antenna ANn from the mobile station UE, and outputs it to the uplink hybrid circuit 237.
  • the upstream hybrid circuit 237 distributes the signal input from the receiving amplifier 236 according to the number of telecommunications carriers and outputs it to the bandpass filter 238.
  • the bandpass filter 238 includes a bandpass filter for each frequency band used by the telecommunications carrier, and each filter outputs only signals in the frequency band used by the corresponding telecommunications carrier.
  • the RSSI detection unit 239 detects the reception strength (RSSI) for the frequency band of each carrier and notifies the control unit 200 of the detection result.
  • the control unit 200 upon receiving the notification, notifies the signal control unit 231 to specify the carrier that will output the signal, and in accordance with this specification, the signal control unit 231 controls the output switch 232 to turn ON/OFF so that only the wireless signal of the specified carrier is output.
  • the control unit 200 is a control center that controls each part of the child unit RUn, and is equipped with a work memory (not shown) and a processor (not shown) that executes processing based on control programs and control data loaded into the work memory from the storage unit 240 (described later), thereby achieving various control functions.
  • the control unit 200 is an example of a switching unit, a forming unit, a detecting unit, and a data communication unit.
  • Specific control functions of the control unit 200 include a communication control function for connecting the mobile station UE, which is wirelessly connected to the slave unit RUn, to the 5G core network 5GC via the master unit MU and the base station device gNB2, and to the LTE core network EPC via the base station device eNB, as well as at least a switching control function 200a, a search control function 200b, and a beamforming control function 200c, and a processing function for integrating and executing these functions.
  • the communication control function detects the telecommunications carrier for the downlink communication signals sent from the base station device gNB2 and the base station device eNB through the communication unit 210 and the signal processing unit 220, and controls the wireless communication unit 230 to transmit the above communication signals in the frequency band of the above telecommunications carrier.
  • the communication control function also detects the telecommunications carrier for the uplink signal received by the wireless communication unit 230 from the mobile station UE, and controls the signal processing unit 220 and the communication unit 210 to transmit the communication signal received from the mobile station UE to the base station device gNB2 of the telecommunications carrier.
  • the beamforming control function 200c controls the massive MIMO performed by the wireless communication unit 230, varies the beam direction, distance and beam width based on the Beam Index map data 240a described below, and performs beamforming according to a specified algorithm depending on the number of streams assigned to the mobile station UE, etc.
  • the beam forming control function 200c controls the direction, distance, and beam width of the beam, for example, as shown in FIG. 5.
  • the beam forming control function 200c can selectively form a sharp narrow beam NB with a narrower beam width and a wide beam WB with a wider beam width in any direction or distance as necessary.
  • FIG. 5 shows the position (direction) of the beam formed by the beam forming control function 200c.
  • the coverage area of the child unit RUn is defined on the xy plane, and the beam forming control function 200c performs beam control to form a narrow beam NB(x,y) with a narrow beam width toward preset coordinates (x,y).
  • the beam forming control function 200c can also perform beam control to form a wide beam WBm (m is any of 1 to 4) with a wide beam width toward each of the four quadrants of the xy plane.
  • the beamforming control function 200c performs control, for example, as shown in FIG. 6, for allocating the number of streams to the mobile station UE. That is, as shown in FIG. 6(a), for example, the beamforming control function 200c divides the multiple antenna elements on the antenna ANn into four array antennas AA1 to AA4 to correspond to the four streams, and controls the directivity of each array antenna in an arbitrary direction.
  • beamforming is performed to direct the stream from array antenna AA2 and the stream from array antenna AA3 in the direction in which the mobile station UE is located.
  • beamforming is performed to direct each stream from array antennas AA1 to AA4 in the direction of the mobile station UE, as shown in FIG. 6(c).
  • the search control function 200b controls the wireless communication unit 230 to search and estimate (detect) the direction and distance of the mobile station UE. Specifically, it controls massive MIMO by the wireless communication unit 230 to repeatedly sweep the direction of the beam in an arbitrary range every 20 ms, for example, as shown in FIG. 7(a), and during this time, monitors the received signal strength successively detected by the wireless communication unit 230 to detect the direction and distance of the mobile station UE.
  • FIG. 7(b) shows the timing of each beam shown in FIG. 7(a), and the matching of shading in both figures indicates the correspondence between direction and timing.
  • control unit 200 can search for the mobile station UE by switching between a high-speed search, a low-speed search, and a tracking search.
  • variable range of the direction in which the beam is pointed (for example, the horizontal direction) is set to approximately 120°, and as shown in FIG. 8(b), the beam is repeatedly swept every 20 ms.
  • the wireless communication unit 230 monitors the received signal strength successively detected, and detects the identification information of the mobile station UE and the direction and distance in which the mobile station UE is located.
  • this high-speed search is performed independently for each of the array antennas AA1 to AA4 on the antenna ANn.
  • the direction searched by each of the array antennas AA1 to AA4 may be set by an operator at the time of installation, or may be set by the search control function 200b itself based on statistical data and learning data of the location information of the mobile station UE accumulated and stored in the memory unit 240, or the settings may be reviewed and updated.
  • variable range of the direction in which the beam is pointed (e.g., horizontal direction) is set to approximately 90°, narrower than the approximately 120° in the fast search described above, and the sweep is repeated every 20 ms as shown in FIG. 9(b).
  • the wireless communication unit 230 monitors the received signal strength successively detected at the same frequency as in the fast search, and the identification information of the mobile station UE and the direction and distance in which the mobile station UE is located are detected more accurately.
  • This slow search is also performed independently for each of the array antennas AA1 to AA4 on the antenna ANn.
  • the direction searched by each of the array antennas AA1 to AA4 is centered on the direction detected in the high-speed search described above.
  • the range of directions to be searched may be limited by an operator during setup, or the search control function 200b may limit it itself based on statistical data and learning data of the location information of the mobile station UE cumulatively stored in the memory unit 240, or the range of the limit may be reviewed.
  • variable range of the direction in which the beam is pointed (for example, the horizontal direction) is set to a trackable range (about 45° in the example of FIG. 10(a)) narrower than the approximately 90° in the slow search described above, and the sweep is repeated every 20 ms as shown in FIG. 10(b).
  • the wireless communication unit 230 monitors the received signal strength successively detected, and more accurately detects the identification information of the mobile station UE and the direction and distance in which the mobile station UE is located.
  • control unit 200 can determine the received signal strength of each beam and the magnitude relationship and changes in the received signal strength in each direction as shown in FIG. 11(b), and therefore can estimate the moving direction of the mobile station UE, and change the pointing direction of the beam to follow the mobile station UE according to this estimation result.
  • the control unit 200 may vary the tracking range based on data learned about the movement of the mobile station UE.
  • the distance between the slave unit RUn and the mobile station UE may also be estimated from the received signal strength, and the variable range may be varied. In this case, if the received signal strength is relatively high, it is determined that the distance between the slave unit RUn and the mobile station UE is close, and the variable range is widened. On the other hand, if the received signal strength is relatively low, it is determined that the distance between the slave unit RUn and the mobile station UE is far, and the variable range is narrowed.
  • the search control function 200b can search in the directions set for the two array antennas AA2 and AA3, even if multiple mobile stations UE1 and UE2 are present in roughly the same direction relative to the antenna ANn, as shown in FIG. 12(a), for example.
  • the change in the received signal strength of mobile station UE1 by array antenna AA2 is as shown in FIG. 12(b), and the change in the received signal strength of mobile station UE2 by array antenna AA3 is as shown in FIG. 12(c).
  • the two array antennas AA2 and AA3 are controlled independently of each other by the control unit 200, so that, for example, while the array antenna AA2 is performing a slow search to track the mobile station UE1, the array antenna AA3 can perform a high-speed search for the mobile station UE2.
  • the search control function 200b also allows one array antenna to search for two or more mobile stations.
  • array antenna AA2 on antenna ANn searches for two mobile stations UE1 and UE2.
  • the received signal strength has two peaks, and the control unit 200 can detect the number of mobile stations present and their directions by detecting the peaks in the received signal strength.
  • the switching control function 200a is a control function that controls the switching of the array antenna included in the antenna ANn that processes the mobile station UE according to the frequency band. Details will be described later.
  • the storage unit 240 stores the control programs and control data used by the control unit 200, as well as the Beam Index map data 240a.
  • the control programs and control data are pre-installed at the time of manufacture, and are also installed or updated through an external interface (not shown) during manufacturing setup, or by communicating with a server on the 5G core network 5GC and the LTE core network EPC of a core device, etc.
  • Beam Index map data 240a is beam direction map data in which the coverage area of the child unit RUn is divided into beam direction sections, for example as shown in FIG. 5, and a Beam Index is assigned to each section. More specifically, the coverage area is divided into sections defined on an x-y plane, and the beam index of a narrow beam directed to each section is NB(x, y), and the beam index of a wide beam directed to each quadrant is WBm, presetting the beam direction.
  • the child units RU1 to RU3 are also positioned so that part of their coverage areas overlap with each other, and this overlapping area forms an overlap area OA, making it possible to direct beams to the same spatial position between the child units, and each child unit RU1 to RU3 sets the above-mentioned Beam Index.
  • the child unit Beam Index map data 140a stored in the memory unit 140 by the parent unit MU is, as described above, a data table that compiles the above-mentioned Beam Index map data 240a of the subordinate child units RU1 to RU3, and for the Beam Index within the overlap area OA, identification information (e.g., an overlap flag) is assigned that indicates that the Beam direction is that of the overlap area OA.
  • identification information e.g., an overlap flag
  • FIGs. 13 to 15 are diagrams showing an example of processing of array antennas in the communication relay system according to the embodiment.
  • Fig. 16 is a diagram showing an example of a time series of terminals and base stations and a time series of array antennas in the communication relay system according to the embodiment.
  • control unit 200 in the child unit RUn executes several control flows in parallel, one of which is the control flow shown in FIG. 16.
  • the control flow shown in FIG. 16 is executed repeatedly until the operation of the child unit RUn is stopped or a stop command is issued to the child unit RUn from the parent unit MU or the like.
  • the control unit 200 causes one or more of the array antennas of the antenna ANn to form an omnidirectional area in the LTE band.
  • the array antenna AA1 first array antenna
  • the array antenna that forms the omnidirectional area in the LTE band is not limited to AA1, and may be AA2 or AA3, or another array antenna not shown.
  • a mobile station UE present within the coverage area formed by the array antenna AA1 transmits a preamble randomly selected from multiple preambles prepared within the coverage area to the base station device eNB (step S1).
  • the base station device eNB When the base station device eNB detects the preamble, it transmits a response information RACH response to the mobile station UE (step S2).
  • the mobile station UE having received the RACH response, transmits a connection request signal (Radio Resource Control (RRC) connection request) to the base station device eNB (step S3).
  • RRC Radio Resource Control
  • the base station device eNB transmits an RRC connection setup, which includes cell setting information for establishing a connection, to the mobile station UE in the connection request signal received signal. After that, the random access process is completed and the connection is established.
  • control unit 200 detects a mobile station UE present within a coverage area where wireless communication with the handset is possible by forming an area omnidirectionally using radio waves output by the array antenna AA1 in the LTE band (or a specific frequency band), and transmits a control signal between the mobile station and the mobile station.
  • control unit 200 may further include an identification unit capable of identifying information such as time-domain weight or frequency-domain weight from a higher-level device.
  • the switching control function 200a of the control unit 200 switches to processing using array antenna AA2 (second array antenna) for the mobile station UE that has established a connection and transmitted a control signal using array antenna AA1.
  • the array antenna AA2 uses the search control function 200b of the control unit 200 to control the wireless communication unit 230 in the LTE band (second frequency band (e.g., 2.1 GHz)) to estimate (detect) the location of the mobile station UE.
  • the LTE band second frequency band (e.g., 2.1 GHz)
  • the search control function 200b controls the wireless communication unit 230 to detect the received signal strength while changing the beam direction, search for the direction and distance where the mobile station UE is located, and detects the beam index corresponding to the direction and distance where the mobile station UE is found as the position of the mobile station UE based on the beam index map data 240a.
  • the LTE band in the array antenna AA1 and the LTE band in the array antenna AA2 may be different frequency bands or the same frequency band.
  • control unit 200 detects the location information of the mobile station UE by switching between multiple array antennas connected to the handset depending on the frequency band and controlling the directivity of the radio waves output by the array antenna AA2 in the LTE band (or a specific frequency band). Note that the Beam Index detected by the array antenna AA2 is shared with other array antennas and used to detect the location information.
  • the array antenna AA3 (third array antenna) controls the wireless communication unit 230 in the NR band using the beamforming control function 200c of the control unit 200, and starts data communication with the mobile station UE with which a connection has been established based on the location information detected from the Beam Index (step S5).
  • the Beam Index detected by array antenna AA2 is shared with each array antenna, and the location information of the mobile station UE is estimated based on the Beam Index indicating the direction of the beam.
  • the array antenna AA3 is then controlled to point the beam direction of array antenna AA3 toward the mobile station UE detected based on the location information in the NR band (third frequency band (e.g., 3.5 GHz or higher and 3.7 GHz or lower)), which is an even higher frequency band than the LTE band, and data communication is started between the array antenna AA3 and the mobile station UE.
  • the NR band third frequency band (e.g., 3.5 GHz or higher and 3.7 GHz or lower)
  • control unit 200 controls the directivity of the radio waves output by the array antenna AA3 in the NR band (or a specific frequency band) based on the position information (Beam Index), and transmits data signals between the mobile station UE.
  • Array antenna AA2 and array antenna AA3 may, for example, have multiple common antenna elements, and array antenna AA2 may share the functions of array antenna AA3 (dual band array). Array antenna AA3 may also be configured to share the functions of array antenna AA3.
  • FIG. 17 is a diagram showing an example of a beam group in an array antenna of a communication relay system according to an embodiment.
  • Beam Group 1 shown in FIG. 17 is, for example, a collection of beam indexes in the positive x-axis direction and the negative y-axis direction in a specified x-y plane, and area formation processing is performed by array antenna AA1.
  • Beam Group 2 shown in FIG. 17 is, for example, a collection of beam indexes in the positive x-axis direction and the positive y-axis direction in a specified x-y plane, and position information detection processing is performed by array antenna AA2.
  • Beam Group 3 shown in FIG. 17 is, for example, a collection of beam indexes in the negative x-axis direction and the positive y-axis direction in a specified x-y plane, and beamforming control and data communication processing are performed by array antenna AA3.
  • Beam Groups change dynamically depending on the number of mobile stations UE, the status of radio resources, etc.
  • All Beam Groups may function as Beam Group 1 to create a wide area using LTE bands and detect more mobile stations UE, or other Beam Groups may be assigned.
  • multiple array antennas form an omnidirectional, or non-directional, area in the LTE band, making it possible to connect to multiple mobile stations UE present within the area and ensuring a high connection rate.
  • the communication relay system of this embodiment in a DAS system equipped with multiple bands, after a connection is established with a mobile station UE, data communication is started, and beamforming control of the array antenna in the NR band is performed based on the location information of the mobile station UE obtained from the Beam Index, thereby obtaining effects such as an increase in the reception level or an improvement in the SINR, and thus making it possible to improve the throughput of the entire communication.

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Mobile Radio Communication Systems (AREA)

Abstract

Un système de relais de communication selon un mode de réalisation de la présente invention comprend : une unité de commutation qui met en œuvre, conformément à une bande de fréquence, la commutation d'antennes réseau connectées à un dispositif esclave ; une unité de formation qui détecte une station mobile existant dans une zone dans laquelle une communication sans fil avec le dispositif esclave peut être mise en œuvre, en formant une zone de manière non directionnelle au moyen d'ondes radio émises par les antennes réseau dans une bande LTE, et qui transfère un signal de commande par rapport à la station mobile ; une unité de détection qui détecte des informations de position de la station mobile en commandant la directionnalité des ondes radio émises par les antennes réseau dans la bande LTE ; et une unité de communication de données qui commande, sur la base des informations de position, la directionnalité d'ondes radio émises par les antennes réseau dans une bande NR, et qui transfère un signal de données par rapport à la station mobile.
PCT/JP2024/003084 2023-02-08 2024-01-31 Système de relais de communication, procédé de relais de communication, et programme WO2024166765A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2023-017851 2023-02-08
JP2023017851A JP2024112654A (ja) 2023-02-08 2023-02-08 通信中継システム、通信中継方法及びプログラム

Publications (1)

Publication Number Publication Date
WO2024166765A1 true WO2024166765A1 (fr) 2024-08-15

Family

ID=92262471

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2024/003084 WO2024166765A1 (fr) 2023-02-08 2024-01-31 Système de relais de communication, procédé de relais de communication, et programme

Country Status (2)

Country Link
JP (1) JP2024112654A (fr)
WO (1) WO2024166765A1 (fr)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002217914A (ja) * 2001-01-19 2002-08-02 Fujitsu General Ltd 無線ｌａｎ用アンテナ装置
JP2004364285A (ja) * 2003-05-30 2004-12-24 Microsoft Corp ワイヤレスネットワーク内の干渉の作用を緩和するための指向性アンテナの使用
JP2004364286A (ja) * 2003-05-30 2004-12-24 Microsoft Corp ワイヤレスネットワークのスループットを向上させるための指向性アンテナの使用
JP2022190884A (ja) * 2021-06-15 2022-12-27 株式会社東芝 通信中継システムおよび無線装置

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002217914A (ja) * 2001-01-19 2002-08-02 Fujitsu General Ltd 無線ｌａｎ用アンテナ装置
JP2004364285A (ja) * 2003-05-30 2004-12-24 Microsoft Corp ワイヤレスネットワーク内の干渉の作用を緩和するための指向性アンテナの使用
JP2004364286A (ja) * 2003-05-30 2004-12-24 Microsoft Corp ワイヤレスネットワークのスループットを向上させるための指向性アンテナの使用
JP2022190884A (ja) * 2021-06-15 2022-12-27 株式会社東芝 通信中継システムおよび無線装置

Also Published As

Publication number Publication date
JP2024112654A (ja) 2024-08-21

Similar Documents

Publication Publication Date Title
US11611965B2 (en) System and method for beam management in high frequency multi-carrier operations with spatial quasi co-location
CN109905150B (zh) 分布式无线天线和毫米波扫描中继器
KR102455768B1 (ko) 무선 통신 시스템에서 빔포밍 설정을 선택하기 위한 시스템 및 방법
CN114982137B (zh) 电子设备、无线通信方法和计算机可读存储介质
WO2006029567A1 (fr) Procede de support flexible d'un service non symetrique dans un systeme de communication mobile tdd a plusieurs porteuses
CN109842890B (zh) 信号测量方法、相关装置及系统
CN110140411B (zh) 5g无线接入网络中的连接建立
US20200229003A1 (en) Access Point Device and Communication Method
CN113632385B (zh) 下行链路参考信号的波束成形接收
US20170339732A1 (en) Communication system, communication device, communication management device, and recording medium
US20240107564A1 (en) Communication relay system and radio device
CN106028362B (zh) 一种室内高密度网络的天线云节点通讯实现方法及系统
US20230171613A1 (en) Communication relay apparatus and storage medium storing computer program
WO2017167532A1 (fr) Dispositif de formation de faisceau pour former différents faisceaux pour un signal de commande et de données
WO2021197576A1 (fr) Procédures de gestion de faisceau pour nœuds réseau et dispositifs terminaux
WO2022014093A1 (fr) Dispositif de relais de communication et support d'enregistrement dans lequel un programme informatique est enregistré
WO2024166765A1 (fr) Système de relais de communication, procédé de relais de communication, et programme
KR20190058057A (ko) 밀리미터파 기반의 인빌딩 릴레이 동작 방법 및 장치
WO2022111818A1 (fr) Signalisation de relation spatiale entre des porteuses composantes
US12256243B1 (en) Repeater device, wireless communication system, and method for ultra-low latency data frame routing using labelling
CN115039347B (zh) 参考信号资源的发送及其配置
KR20130128028A (ko) 통신 시스템에서 협업 통신을 수행하는 장치 및 방법
WO2024228532A1 (fr) Planification et conception de faisceau dans un jpta
CN111512563B (zh) 用于朝向用户实体传送数据流的基站系统
JP2004235839A (ja) 固定無線アクセスシステム

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 24753208

Country of ref document: EP

Kind code of ref document: A1