Method for communication between a terminal, a repeater and a base station

Abstract

To provide a base station, etc., in which a terminal is capable of controlling a communication system in response to the interposition of a repeater in a RAN.SOLUTION: A first communication system in which the interposition of a repeater is not recognized and a second communication system in which the interposition of a repeater is recognized are applicable as a terminal. A base station transmits control information instructing the second communication system to the terminal via the repeater. A carrier aggregation of frequency multiplexing is applied to an uplink from the terminal. In the first communication system, one physical packet consists of one component carrier, and a plurality of component carriers is multiplexed and transmitted. In the second communication system, one physical packet is divided into a plurality of sub physical packets, one sub physical packet consists of one component carrier, and a plurality of component carriers is multiplexed and transmitted.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a repeater technology deployed in a Radio Access Network (RAN), and in particular to a Network Control Repeater (NCR) used in the 5G standard. [Background technology]

[0002] FIG. 1 is a system configuration diagram of a RAN including a repeater.

[0003] The mobile communication system is composed of a mobile terminal 3, a plurality of base stations 2, and a core system 4. 1, a repeater 1 is interposed in a RAN that is configured between a base station 2 and a terminal 3. The repeater 1 amplifies and relays radio signals, thereby expanding the coverage (radio wave range) between the base station 2 and the terminal 3.

[0004] The terminal 3 is called "UE (User Equipment)" and communicates with the core system 4 via the base station 2. In this case, the terminal 3 generally communicates radio signals with the base station 2 without being aware of the presence of the repeater 1. Of course, the terminal 3 does not exchange control information with the repeater 1.

[0005] The base station 2 is called a "gNB" and communicates with multiple terminals 3 directly or via a repeater 1. The base station 2 may be physically separate, or may be logically divided within the RAN using, for example, virtualization technology or slicing technology.

[0006] The core system 4 is composed of control plane equipment and user plane equipment. The control plane facility devices are a group of network devices that transmit and receive control signals for establishing communication and the like, and include a group of network devices such as an Access and Mobility Management Function (AMF) and a Session Management Function (SMF). The user plane facility equipment includes a group of UPF (User Plane Function) devices for transmitting and receiving user data.

[0007] FIG. 2 is an explanatory diagram showing a direct communication method between a terminal and a base station.

[0008] FIG. 2(a) shows a direct communication method between a terminal 3 and a base station 2. In FIG. Link (base station-terminal): 28GHz band, 400MHz width, spatial multiplexing 1 The terminal 3 configures one physical packet with one component carrier, and transmits the one component carrier to the base station 2.

[0009] FIG. 2(b) shows a direct communication method using a frequency multiplexing section method between the terminal 3 and the base station 2. Link (base station-terminal): 39 GHz band, 1.6 GHz width (4CC), spatial multiplexing 1 Access link (repeater terminal): 39 GHz band, 1.6 GHz width (4CC), spatial multiplexing 1 Backhaul link (base station - repeater): 39 GHz band, 1.6 GHz width (4CC), spatial multiplexing 1

[0010] Here, the repeater 1 is an RF (Radio Frequency) repeater that simply amplifies and forwards wireless signals. Because the repeater 1 has a physical layer amplification function, the communication method for the backhaul link and the access link is the same. Of course, the base station 2 and the terminal 3 do not need to be aware of the presence of the repeater 1.

[0011] Terminal 3 transmits physical packets in the uplink using frequency multiplexing carrier aggregation (see, for example, Non-Patent Document 7). Terminal 3 configures one physical packet with one component carrier and transmits four component carriers simultaneously using carrier aggregation. Base station 2 receives the four physical packets simultaneously.

[0012] FIG. 3 is a diagram showing the protocol configuration between a base station and a terminal via a repeater.

[0013] The repeater 1 of the NCR based on the 5G RAN standard has a control plane function and receives control from the base station (see, for example, Non-Patent Document 3). 3, the repeater 1 has a control plane function 11 and a user plane function 12. The control plane function 11 is NCR-MT (Mobile Termination), and the user plane function 12 is NCR-Fwd (Forwarding).

[0014] <Control plane function 11> The control plane function 11 establishes a control link with the base station 2. According to Fig. 3, the control plane function 11 has the following protocol configuration. RRC (Radio Resource Control) PDCP (Packet Domain Convergence Protocol) RLC (Radio Link Control) MAC (Media Access Control) Physical Layer

[0015] <User plane function 12> The user plane function 12 establishes a backhaul link with the base station 2 and an access link with the terminal 3. According to FIG. 3, the following protocol configuration is provided. SDAP (Service Data Adaptation Protocol) PDCP (Packet Domain Convergence Protocol) RLC (Radio Link Control) MAC (Media Access Control) Physical Layer

[0016] When the control plane function 11 receives a paging message from the base station 2, it transitions to a connected state and establishes a control link with the base station 2. Then, the control plane function 11 transitions the forwarding unit of the user plane function 12 to an ON state. After that, the repeater 1 starts amplifying and forwarding the radio signal to relay it between the base station 2 and the terminal 3. [Prior art documents] [Non-patent literature]

[0017] [Non-Patent Document 1] 3GPP, TS 36.211, “Evolved Universal Terrestrial Radio Access (E UTRA );Physical channels and modulation”, v17.2.0 [Non-patent document 2] 3GPP, TS 36.213, “Evolved Universal Terrestrial Radio Access (E UTRA );Physical layer procedures”, v17.2.0 [Non-patent document 3] 3GPP, TR 38.867, “Study on NR network controlled repeaters”, v0.1.0 [Non-patent document 4] 3GPP, TS 38.213, “Physical layer procedures for control”, v17.2.0 [Non-Patent Document 5] 3GPP, TS 38.331, “Radio Resource Control (RRC) protocol specification”, v17.1.0 [Non-patent document 6] 3GPP, TS 38.211, “Physical channels and modulation”, v17.2.0, 6.3.1.3 Layer mapping, Table 7.3.1.3 1: Codeword to layer mapping for spatial multiplexing [Non-Patent Document 7] "5G / NR - Carrier Aggregation", [online], [searched September 15, 2022], Internet<URL:https: / / www.sharetechnote.com / html / 5G / 5G_CarrrierAggregation.html> [Non-patent document 8] "5G / NR - MIMO UL", [online], [searched September 15, 2022], Internet<URL:https: / / www.sharetechnote.com / html / 5G / 5G_MIMO_UL.html> Summary of the Invention [Problem to be solved by the invention]

[0018] FIG. 4 is an explanatory diagram showing a conventional RAN using a repeater of the multiple axis conversion method.

[0019] According to the multiple axis conversion method of FIG. 4, the repeater 1 applies frequency multiplexing carrier aggregation to the access link and spatial multiplexing MIMO (Multi Input Multi Output) to the backhaul link (see, for example, Non-Patent Document 8).

[0020] According to FIG. 4, from the perspective of the repeater 1, the communication method of the access link and the communication method of the backhaul link are different. Access link (repeater terminal): 39 GHz band, 1.6 GHz width (4CC), spatial multiplexing 1 Backhaul link (base station-repeater): 28 GHz band, 400 MHz width, spatial multiplexing 4

[0021] The repeater 1 converts between signals on the frequency axis and signals on the space axis during relaying. By using the multiple axis conversion method, the repeater 1 can achieve high-capacity, low-latency communication from the terminal 3 to the base station 2.

[0022] For the access link, the terminal 3 transmits a physical packet to the repeater 1 by frequency multiplexing carrier aggregation. The terminal 3 configures one physical packet with one component carrier, and transmits four component carriers simultaneously by carrier aggregation. The repeater 1 simultaneously receives four component carriers from the terminal 3 via carrier aggregation for the access link.

[0023] For the backhaul link, the repeater 1 transmits component carriers to the base station 2 using spatial multiplexing MIMO. Typically, in MIMO, one physical packet (here, a component carrier) is composed of, for example, four layer blocks. The repeater 1 amplifies each of the four component carriers received simultaneously, and then simultaneously transmits them to the base station 2 in four layer blocks.

[0024] Here, the base station 2 simultaneously receives four component carriers in four layer blocks. At this time, the base station 2 encounters a problem in that it attempts to demodulate one physical packet from the four simultaneously received layer blocks through MIMO reception processing, but fails. To be precise, four physical packets must be demodulated from the four simultaneously received layer blocks.

[0025] In response to this, terminal 3 can also transmit in advance a physical packet configuration that corresponds to the presence of repeater 1. However, terminal 3 is not aware of the presence of repeater 1 in the RAN. Furthermore, repeater 1 cannot transmit a control signal to terminal 3 to notify the terminal of the relay method. In other words, terminal 3 cannot control the communication method depending on the presence of repeater 1 in the RAN.

[0026] Therefore, an object of the present invention is to provide a base station, a terminal, a program, a system, and a communication method that enable a terminal to control a communication method depending on the presence of a repeater in a RAN. [Means for solving the problem]

[0027] The present invention Communication method According to a first step in which a terminal configures one physical packet with one component carrier and frequency-multiplexes and transmits the multiple component carriers in an uplink as a first communication scheme; a second step of transmitting control information instructing the terminal to use the second communication method via the repeater in a downlink from the base station; a third step in which, after receiving the control information, the terminal divides one physical packet into a plurality of child physical packets, configures one child physical packet with one component carrier, and frequency-multiplexes the plurality of component carriers and transmits the child physical packets in an uplink as a second communication method; The repeater, when receiving multiple frequency-multiplexed component carriers from the terminal simultaneously, configures each component carrier into a layer block, spatially multiplexes the multiple layer blocks, and transmits them to the base station in the fourth step. The present invention is characterized by having the following.

[0028] The present invention Communication Method According to another embodiment in For the second step, the base station: After establishing a control link with the repeater and establishing a random access channel with the terminal via the repeater, In the downlink, control information instructing the second communication method is transmitted. It is also preferable. [Effects of the Invention]

[0038] According to the base station, terminal, program, system, and communication method of the present invention, the terminal can control the communication method depending on the presence of a repeater in the RAN. [Brief explanation of the drawings]

[0039] [Figure 1] FIG. 1 is a system configuration diagram of a RAN including a repeater. [Figure 2] FIG. 1 is an explanatory diagram illustrating a direct communication method between a terminal and a base station. [Figure 3] FIG. 10 is a diagram illustrating a protocol configuration between a base station and a terminal via a repeater. [Figure 4] FIG. 1 is an explanatory diagram showing a conventional RAN using a multiple axis conversion repeater. [Figure 5] FIG. 1 is an explanatory diagram showing a RAN in accordance with the present invention, which includes a repeater using a multiple axis conversion method. [Figure 6] FIG. 1 is a sequence diagram of a RAN in the present invention with a repeater interposed therebetween. DETAILED DESCRIPTION OF THE INVENTION

[0040] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0041] According to the present invention, communication is performed between the base station and the terminal directly or by relaying via a repeater. Here, the terminal can apply the following two communication methods depending on whether or not a repeater of the multiple axis conversion method is used. "First communication method": Multiple axis conversion method without repeater intervention "Second communication method": With the use of a repeater of the multi-axis conversion method That is, when the repeater applies the "direct communication method" that relays by simply amplifying and forwarding the wireless signal, the terminal applies the "first communication method." On the other hand, when the repeater applies the "multi-axis conversion method" between the access link and the backhaul link, the terminal applies the "second communication method."

[0042] According to the present invention, the terminal applies a first communication method in which the radio signal is simply amplified and transferred in exactly the same manner as in FIG. 2(b) described above. Link (base station-terminal): 39 GHz band, 1.6 GHz width (4CC), spatial multiplexing 1 Access link (repeater terminal): 39 GHz band, 1.6 GHz width (4CC), spatial multiplexing 1 Backhaul link (base station - repeater): 39 GHz band, 1.6 GHz width (4CC), spatial multiplexing 1 According to FIG. 2(b) described above, frequency multiplexed carrier aggregation is applied to the uplink from terminal 3. In the first communication method, one physical packet is composed of one component carrier, and then, for example, four component carriers are transmitted simultaneously by carrier aggregation. The base station 2 receives four component carriers simultaneously, regardless of whether the repeater 1 is present or not.

[0043] FIG. 5 is an explanatory diagram showing a RAN in accordance with the present invention, which includes a repeater of the multiple axis conversion type.

[0044] According to the present invention, the terminal applies the second communication method as shown in FIG. Access link (Repeater 1 - Terminal 3): 39 GHz band, 1.6 GHz width, 4 CC Backhaul link (base station 2 - repeater 1): 28 GHz band, 400 MHz width, spatial multiplexing 4

[0045] In FIG. 5 as well, frequency multiplexed carrier aggregation is applied to the uplink from terminal 3. In the second communication method, one physical packet is divided into, for example, four child physical packets, and each child physical packet is configured with one component carrier.Then, these four component carriers are transmitted simultaneously by carrier aggregation. Repeater 1 will receive four component carriers simultaneously.

[0046] Also, according to FIG. 5, MIMO spatial multiplexing is applied to the uplink from repeater 1. For the access link, the repeater 1 simultaneously receives four component carriers (four child physical packets) using frequency multiplexing carrier aggregation. In contrast, spatial multiplexing MIMO configures each component carrier received from the terminal 3 as a layer block. In other words, the repeater 1 multiplexes and transmits the four layer blocks from multiple antenna elements. Using MIMO, base station 2 can simultaneously receive four layer blocks from repeater 1 and demodulate them into one physical packet.

[0047] 5, it should be noted that, for the second communication method, the terminal 3 transmits, for example, four child physical packets to the repeater 1 using four component carriers (= one physical packet), and the repeater 1 forwards the four component carriers to the base station 2 using four layer blocks. In other words, the repeater 1 only amplifies in component carrier units (= child physical packets). In response to this, the base station 2 simultaneously receives four component carriers in four layer blocks, and can demodulate one physical packet from the four simultaneously received layer blocks.

[0048] FIG. 6 is a sequence diagram of the RAN in the present invention with a repeater interposed therebetween.

[0049] According to FIG. 6, as in the above-described FIG. 5, the terminal 3 is capable of applying the first communication method and the second communication method. (S1) First, base station 2 establishes a control link with repeater 1 over the backhaul link. (S2) Next, the base station 2 establishes a random access channel with the terminal 3 via the repeater 1. (S3) Next, the base station 2 establishes an RRC (Radio Resource Control) connection with the terminal 3 via the repeater 1. At this time, terminal 3 attempts to apply the default "first communication method" for frequency multiplexing carrier aggregation. According to the first communication method, terminal 3 configures one physical packet with one component carrier and transmits, for example, four component carriers simultaneously.

[0050] (S4) Assume that the base station 2 applies spatial multiplexing MIMO transmission to the uplink via a control link with the repeater 1. At this time, the base station 2 includes "control information (second communication scheme)" in RRC Reconfiguration and transmits it to the terminal 3 via the repeater 1 so that the terminal 3 applies the "second communication scheme."

[0051] (S5) The terminal 3 applies the second communication method to frequency multiplexing carrier aggregation. According to the second communication method, the terminal 3 divides one physical packet into, for example, four child physical packets. Then, one child physical packet is configured with one component carrier. That is, one physical packet is divided into, for example, four component carriers, and the four component carriers are transmitted simultaneously by carrier aggregation.

[0052] As described above in detail, the base station, terminal, program, system, and communication method of the present invention enable the terminal to control the communication method depending on the presence of a repeater in the RAN. Specifically, even if the access link uses a frequency multiplexing method and the backhaul link uses a repeater that uses a multiple axis conversion method such as a spatial multiplexing method, the repeater only amplifies on a component carrier basis, and base station 2 will not fail to reconstruct a single physical packet.

[0053] Furthermore, this will enable, for example, "high-capacity, low-latency communications to be achieved for the RAN between base stations and terminals by using repeaters as an intermediary," which will contribute to Goal 9 of the United Nations-led Sustainable Development Goals (SDGs), which is to "build resilient infrastructure, promote sustainable industrialization, and foster innovation."

[0054] With respect to the various embodiments of the present invention described above, various changes, modifications, and omissions that fall within the scope of the technical spirit and aspects of the present invention may be easily made by those skilled in the art. The above description is merely illustrative and is not intended to be limiting in any way. The present invention is limited only by the claims and their equivalents. [Explanation of symbols]

[0055] 1 repeater 11 Control Plane Functions 12 User Plane Functions 2 base station 3. Terminal 4 Core System

Claims

1. A first step in which a terminal, in an uplink, transmits one physical packet composed of one component carrier, frequency-multiplexing the multiple component carriers, as a first communication method; a second step of transmitting control information instructing the terminal to use the second communication method via the repeater in a downlink from the base station; a third step in which, after receiving the control information, the terminal divides one physical packet into a plurality of child physical packets, configures each child physical packet with one component carrier, and frequency-multiplexes the plurality of component carriers and transmits the child physical packets in uplink as a second communication method; a fourth step in which, when the repeater simultaneously receives a plurality of frequency-multiplexed component carriers from the terminal, the repeater configures each component carrier into a layer block, spatially multiplexes the plurality of layer blocks, and transmits the layer blocks to the base station in the uplink; A communication method comprising:

2. In the second step, the base station establishes a control link with the repeater, establishes a random access channel with the terminal via the repeater, and then transmits control information instructing the second communication method on the downlink.

2. The communication method according to claim 1.

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