Control device, relay station, and control method

Abstract

The present disclosure enables appropriate communication when a non-reproduction relay is used. A control device according to an aspect of the present disclosure comprises: a control unit that identifies a second terminal station for which interference may occur due to non-reproduction relay between a base station and a first terminal station via a relay station; and a communication unit that notifies the relay station of stop of the non-reproduction relay when a first condition related to a signal to interference plus noise ratio (SINR) of a signal received by the second terminal station from the base station is satisfied at a timing of the execution of the non-reproduction relay.

Description

Control device, relay station and control method

[0001] The present disclosure relates to a control device, a relay station, and a control method in a mobile communication system.

[0002] The New Radio (NR) technical specifications of the 3rd Generation Partnership Project (3GPP (registered trademark)), a standardization project for mobile communication systems, have introduced non-regenerative relaying as a low-latency relaying technology (see, for example, Non-Patent Document 1). Non-regenerative relaying does not perform demodulation and decoding at the relay station, so relaying with low latency is possible.

[0003] 3GPP TS 38.106 V18.1.0(2023-06)

[0004] However, when non-regenerative relaying is performed, terminal stations that do not use relaying may be subject to interference from the non-regenerative relaying, resulting in a deterioration in communication quality and a decrease in communication throughput.

[0005] Therefore, one of the objects of the present disclosure is to provide a control device, a relay station, and a control method that can appropriately perform communication when non-regenerative relay is used.

[0006] A control device according to one aspect of the present disclosure includes a control unit that identifies a second terminal station that is at risk of interference due to non-regenerative relaying between a base station and a first terminal station via a relay station, and a communication unit that notifies the relay station to stop the non-regenerative relaying when a first condition related to a received signal to interference plus noise ratio (SINR) of a signal received by the second terminal station from the base station is satisfied at the time the non-regenerative relaying is performed.

[0007] According to one aspect of the present disclosure, communication can be performed appropriately when non-regenerative relay is used.

[0008] FIG. 1 is a diagram illustrating an example of a schematic configuration of a system according to an embodiment of the present disclosure. FIG. 2 is a diagram illustrating an example of a schematic functional configuration of each device according to an embodiment of the present disclosure. FIG. 3 is a diagram illustrating an example of a schematic hardware configuration of each device according to an embodiment of the present disclosure. FIGS. 4A and 4B are diagrams illustrating an example of a variation in the hardware configuration of a base station according to an embodiment of the present disclosure. FIGS. 5A to 5D are diagrams illustrating an example of a problem associated with non-regenerative relay. FIG. 6 is a diagram illustrating an example of a first control flow according to an embodiment of the present disclosure. FIG. 7 is a diagram illustrating a first control flow according to an embodiment of the present disclosure. ＲＸ，ｍｉｎ ＵＥｉ FIG. 8 is a diagram showing an example of parameters for calculating D ＵＥｉ 9 is a diagram showing an example of the value of γ ＲＸ ＵＥｉ 10 is a diagram illustrating an example of a second control flow according to an embodiment of the present disclosure. FIG. 11 is a diagram illustrating an example of a third control flow according to an embodiment of the present disclosure. FIG. 12 is a diagram illustrating an example of SS-SINR measurement report mapping. FIG. 13 is a diagram illustrating an example of I Ｒ→ＵＥｉ FIG. 14 is a diagram showing an example of parameters for calculating γ ＲＸ ＵＥｉ，１ 15 is a diagram showing an example of parameters for calculating the relay station R １ and R ２ γ when trying to perform non-regenerative relay ＲＸ，ｍｉｎ ＵＥｉ 16 is a diagram showing an example of parameters for calculating the relay station R １ and R ２ γ when non-regenerative relay is performed ＲＸ ＵＥｉ FIG. 10 is a diagram illustrating an example of parameters for calculating

[0009] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In this specification and the drawings, elements that can be similarly described will be denoted by the same reference numerals, and redundant description may be omitted.

[0010] In the present disclosure, "A / B" and "at least one of A and B" may be interpreted interchangeably. Also, in the present disclosure, "A / B / C" may mean "at least one of A, B, and C."

[0011] <System Configuration> Fig. 1 is a diagram illustrating an example of a schematic configuration of a system according to an embodiment of the present disclosure. The system 1 includes a control device 10, a base station 20, a relay station 30, and a terminal station 40. The system 1 may also be referred to as a wireless communication system, an information communication system, or the like.

[0012] For example, the system 1 is a system that complies with the Technical Specification (TS) of 3GPP. More specifically, the system 1 is a system that complies with the TS of the 5th generation mobile communication system (5G) or New Radio (NR).

[0013] Note that system 1 is not limited to this example, and may include systems that use Long Term Evolution (LTE), LTE-Advanced (LTE-A), 4th generation mobile communication system (4G), 5th generation mobile communication system (5G), 6th generation mobile communication system (6G), xth generation mobile communication system (xG (x is, for example, an integer or a decimal)), New Radio (NR), Global System for Mobile communications (GSM (registered trademark)), CDMA2000, Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE 802.20, Ultra-WideBand (UWB), Bluetooth (registered trademark), and other wireless communication methods, as well as next-generation systems that are extended, modified, created, or defined based on these.

[0014] In system 1, the communication link going to (receiving from) the base station 20 / going out (transmitting from) the terminal station 40 may be called the uplink (UL), and the communication link going out (transmitted from) the base station 20 / going out (receiving from) the terminal station 40 may be called the downlink (DL).

[0015] The control device 10 may be a device on a core network to which the base station 20 is connected. The control device 10 may be called a network node and may provide network functions (Network Functions (NF)). The NF may be, for example, at least one of an Access and Mobility management Function (AMF), an Application Function (AF), a Data Network (DN), a Location Management Function (LMF), Operation, Administration and Maintenance (Management) (OAM), a Session Management Function (SMF), a Unified Data Management (UDM), a User Plane Function (UPF), and the like.

[0016] The core network includes, for example, an optical fiber network. In the present disclosure, the network and the core network may be read interchangeably.

[0017] The control device 10 may control at least one of the base station 20, the relay station 30, and the terminal station 40, and may perform control to provide communication services between the base station 20 / relay station 30 and the terminal station 40. The control device 10 may be included in the base station 20.

[0018] The base station 20 provides a radio access network (Radio Access Network (RAN)) to the terminal station 40. An area where wireless communication is possible in the radio access network is also called a cell. The base station 20 is, for example, a gNB. The gNB is a node that provides NR user plane and control plane protocol terminations towards the UE and is connected to a 5G core network (5GC) via an NG interface. The base station 100 may be an en-gNB. The en-gNB is a node that provides NR user plane and control plane protocol terminations towards the UE and operates as a secondary node in E-UTRA-NR Dual Connectivity (EN-DC).

[0019] The relay station 30 performs non-regenerative relaying of communications between the base station 20 and the terminal station 40. In non-regenerative relaying, demodulation / decoding of the relayed signal is not performed, so communications can be relayed with a delay that does not change the slot timing. In this disclosure, non-regenerative relaying may mean relaying (transferring) without demodulation / decoding processing, amplification and transfer of UL / DL radio signals between the base station and the terminal station, repeating, etc. Note that in this disclosure, relaying, forwarding, repeating, transmission, etc. may be interpreted as interchangeable terms.

[0020] The relay station 30 may be a Radio Frequency (RF) repeater, a Network-Controlled Repeater (NCR), an Integrated Access and Backhaul (IAB), or other repeater. The relay station 30 may also be called, for example, a small base station, a mobile base station, a relay base station, or the like.

[0021] For example, the NCR may include an NCR-Mobile Termination (NCR-MT) and an NCR-Forwarding (NCR-Fwd). The NCR-MT can communicate with the base station 20 via a control link (e.g., receive configuration / control information and send requests / reports). The NCR-Fwd can relay communications between the base station 20 and the terminal station 40 by relaying / amplifying signals from the backhaul link (with the base station 20) to the access link (with the terminal station 40) and from the access link to the backhaul link.

[0022] The relay station 30 may perform non-regenerative relay using different frequency resources or the same frequency resources for the multiple terminal stations 40. The relay station 30 may transmit non-regenerative relay signals for the multiple terminal stations 40 using frequency division multiplexing (FDM), time division multiplexing (TDM), space division multiplexing (SDM), or other multiplexing methods.

[0023] One or more relay stations 30 may share information about resources (e.g., frequency / time resources, resource blocks (RBs)) used by each terminal station 40. The information may be communicated between relay stations 30, or may be communicated from the base station 20 to the relay station 30.

[0024] The terminal station 40 is connected to the radio access network in the above-mentioned cell and corresponds to a UE. The terminal station 40 may be, for example, a mobile terminal (mobile communication terminal) such as a smartphone, tablet terminal, or wearable terminal, or may be a fixed communication terminal. Each terminal station 40 may be able to receive the control signal transmitted by the base station 20 directly or via the relay station 30.

[0025] In the present disclosure, a terminal station to which non-regenerative relay communication is applied (in other words, a terminal station that communicates with the base station 20 via the relay station 30) is referred to as terminal station 40a, and a terminal station to which non-regenerative relay communication is not applied (in other words, a terminal station that communicates with the base station 20 without the relay station 30) is also referred to as terminal station 40b. When simply referred to as terminal station 40, this may include both terminal station 40a and terminal station 40b. A terminal station that is subject to non-regenerative relay (terminal station 40a) may be called a first terminal station. A terminal station that is not subject to non-regenerative relay (terminal station 40b) may be called a second terminal station.

[0026] Each of the base station 20, relay station 30, terminal station 40, etc. may include a fixed station whose installation location is fixed, or may include a mobile station.

[0027] The unregenerative repeat signal in DL communication may correspond to a signal transmitted from the relay station 30 to the terminal station 40. The unregenerative repeat signal in UL communication may correspond to a signal transmitted from the relay station 30 to the base station 20.

[0028] In addition, in the system 1, TDM or Time Division Duplex (TDD) may be used, in which UL communication and DL communication are performed on the same frequency channel. Also, in the system 1, the timing of slots / frames may be synchronized (aligned) among all stations.

[0029] In addition, in the system 1, cyclic prefix-orthogonal frequency division multiplexing (CP-OFDM) (or a multi-carrier waveform) may be used for at least one of UL and DL communications, or discrete Fourier transform-spread-orthogonal frequency division multiplexing (DFT-s-OFDM) (or a single-carrier waveform) may be used. In the system 1, other waveforms (e.g., filtered OFDM (F-OFDM)) may be used for UL / DL communications.

[0030] <Configuration of Each Device> An example of the configuration of each device (control device 10, base station 20, relay station 30, terminal station 40) according to an embodiment of the present disclosure will be described.

[0031] 2 is a diagram illustrating an example of a schematic functional configuration of each device according to an embodiment of the present disclosure. For example, the control device 10 includes a control unit 110, a communication unit 120, an input / output unit 130, and a storage unit 140.

[0032] Note that the base station 20, relay station 30, and terminal station 40 may also have similar functional configurations. For this reason, in Fig. 2, the reference numerals of the functional blocks corresponding to each device are also shown in which the highest digit of the reference numeral representing each device (for example, the highest digit of "20" for base station 20 is "2") is replaced with "1". The following describes the functional blocks related to the control device 10, but it will be understood that the same description applies to the other devices.

[0033] In this example, functional blocks of the characteristic parts of this embodiment are mainly shown, and each device may also have other functional blocks necessary for other processes. Also, a configuration may be possible in which some functional blocks are not included.

[0034] The control unit 110 controls the control device 10 and provides various functions. For example, the control unit 110 may control communication with other devices via the communication unit 120. The control unit 110 may also acquire information necessary for processing based on information received via the communication unit 120. The control unit 110 may also be referred to as a processing unit.

[0035] The communication unit 120 communicates (transmits / receives) with other devices via a network. The communication unit 120 may output information obtained from a received signal to the control unit 110, or may convert information input from the control unit 110 into a signal and transmit it. The communication unit 120 may also be called a transmitting unit, a receiving unit, a transmitting / receiving unit, etc.

[0036] The input / output unit 130 may include an input unit that accepts input through user operation. The input unit may be connected to a predetermined device, storage medium, etc., and may accept data input. The input unit may output the input result to the control unit 110, for example.

[0037] The input / output unit 130 may also include an output unit that outputs data, content, etc. in a format that can be perceived by the user. The output unit may include a display unit that displays images, an audio output unit that outputs audio, etc.

[0038] The storage unit 140 stores (holds) various information used for processing by the control device 10. The control unit 110 may instruct the storage unit 140 to read and write data.

[0039] 3 is a diagram illustrating an example of a schematic hardware configuration of each device according to an embodiment of the present disclosure. Each device includes an antenna 510, a radio frequency (RF) circuit 520, a processor 530, a network interface 540, an input device / output device 550, a memory 560, and a storage 570.

[0040] The hardware configuration of each device may be configured to include one or more of the elements shown in Fig. 3, or may be configured to exclude some of the elements. For example, the relay station 30 and the terminal station 40 may not have the network interface 540.

[0041] The antenna 510 converts signals into radio waves and radiates the radio waves into space. The antenna 510 also receives radio waves in space and converts the radio waves into signals. The antenna 510 may include a transmitting antenna and a receiving antenna, or may include a single antenna for both transmission and reception. The antenna 510 may include a directional antenna or may include multiple antenna elements.

[0042] The relay station 30 may be equipped with a plurality of antennas 510. For example, the relay station 30 may have an antenna that is separate from the antenna used for the relay line, so that the control unit 310 can receive notifications related to control.

[0043] The RF circuitry 520 performs analog processing of signals transmitted and received via the antenna 510. The RF circuitry 520 may include filters (e.g., high frequency filters, low pass filters), amplifiers, modulators, frequency synthesizers, analog-to-digital conversion circuits, digital-to-analog conversion circuits, inverse fast Fourier transform (IFFT)) processing circuits, and the like.

[0044] The RF circuit 520 may perform amplification, filtering, demodulation to a baseband signal, etc. on the received radio frequency band signal, and output the signal to the processor 530. The RF circuit 520 may perform modulation to a radio frequency band, filtering, amplification, etc. on the baseband signal input from the processor 530, and transmit the radio frequency band signal via the transmitting / receiving antenna 510. Note that the RF circuit 520 may perform physical layer processing (e.g., processing of lower functions of the physical layer), and may perform beamforming processing such as analog beamforming processing and digital beamforming processing.

[0045] The processor 530 may control the entire device. The processor 530 may read programs (program codes), software (software modules), data, etc. from the storage 570 into the memory 560 and execute various processes in accordance with the programs. The processor 530 may be configured by a central processing unit (CPU) including an interface with peripheral devices, a control unit, an arithmetic unit, a register, etc. The processor 530 may also include a microprocessor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a programmable logic device (PLD), a field programmable gate array (FPGA), etc.

[0046] The processor 530 may perform digital processing of signals transmitted and received via the antenna 510 and the RF circuitry 520. The digital processing may include physical layer processing (e.g., processing of functions higher than the physical layer), processing of the Medium Access Control (MAC) layer or higher, modulation, demodulation, encoding, decoding, scrambling, etc. The processor 530 also processes signals transmitted and received via the network interface 540.

[0047] The processor 530 may include multiple processors or may be a single processor, which may include a baseband processor that performs the digital processing and one or more processors that perform other processing (e.g., overall control).

[0048] The network interface 540 is, for example, a network adapter, and may be connected to an external network via a wired connection to send and receive signals.

[0049] The RF circuit 520, the baseband processor, and the network interface 540 may be integrated into one unit. The RF circuit 520, the baseband processor, and the network interface 540 may be called a network controller, a network card, a communication module, or the like.

[0050] The input device / output device 550 includes input devices that accept input from the outside (e.g., keyboards, mice, microphones, switches, buttons, sensors, etc.), output devices that output to the outside (e.g., displays, speakers, Light Emitting Diode (LED) lamps, etc.), and devices that combine these (e.g., touch panels).

[0051] The memory 560 is a computer-readable non-transitory recording medium that stores programs executed by the processor 530, parameters related to the programs, and various other information. The memory 560 may include at least one of a read-only memory (ROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), a random access memory (RAM), and a flash memory. All or a part of the memory 560 may be included within the processor 530. The memory 560 may also be called a register, a cache, a main memory, etc.

[0052] Storage 570 is a computer-readable non-transitory recording medium and stores various information. Storage 570 may include, for example, at least one of a flexible disk, a floppy (registered trademark) disk, a magneto-optical disk (e.g., a compact disc ROM (CD-ROM)), a digital versatile disc, a Blu-ray (registered trademark) disc), a removable disk, a hard disc drive (HDD), a smart card, a flash memory device (e.g., a solid state drive (SSD)), and the like. Storage 570 may also be referred to as an auxiliary storage device.

[0053] Furthermore, each device such as the processor 530 and the memory 560 may be connected by a bus for communicating information. A single bus may be used within the device, or different buses may be used between the devices.

[0054] The control unit X10 (X=1, 2, 3, 4; the same applies below) may be implemented by the processor 530. The communication unit X20 may be implemented by the antenna 510 / RF circuit 520 / network interface 540. The input / output unit X30 may be implemented by the input device / output device 550. The storage unit X40 may be implemented by the memory 560 / storage 570.

[0055] (Variations in Hardware Configuration of Base Station) The communication processing function of a base station (RAN) may be separated into three elements: a Radio Unit (RU), a Distributed Unit (DU), and a Central Unit (CU). The RU performs RF processing and lower-level functions of the physical layer. The DU performs higher-level functions of the physical layer, MAC layer functions, and Radio Link Control (RLC) layer functions. The CU performs Packet Data Convergence Protocol (PDCP) layer, Service Data Adaptation Protocol (SDAP), and Radio Resource Control (RRC) layer functions.

[0056] 4A and 4B are diagrams illustrating an example of a variation of the hardware configuration of a base station according to an embodiment of the present disclosure. In this example, for simplicity, only the antenna 510, the RF circuit 520, and the processor 530 are illustrated among the elements described in FIG. 3, but the other elements may be included in a device equipped with the processor 530.

[0057] 4A, one base station 20 includes an antenna 510, an RF circuit 520, and a processor 530. This base station 20 has a configuration in which an RU and a DU / CU are integrated.

[0058] 4B , one base station 20a includes only an antenna 510 and an RF circuit 520, and another base station 20b includes a processor 530, and these base stations are connected by an optical fiber line or the like. The former base station 20a has only an RU, so it may be called a slave station or a distributed base station. The latter base station 20b has only a DU / CU, so it may be called a master station or a central base station.

[0059] In addition, the base station of the RU / DU and the base station of the CU may be connected, or the base station of the RU, the base station of the DU and the base station of the CU may be connected.

[0060] In the present disclosure, the base station 20 may include one base station (node) that implements all of the functions of the RU, DU, and CU as shown in Fig. 4A, or may include multiple base stations (nodes) that each implement some of the functions of the RU, DU, and CU as shown in Fig. 4B. For example, the base station 20 may refer to a base station configured of a distributed base station 20a and a central base station 20b.

[0061] <Issue Analysis> Figures 5A-5D are diagrams showing an example of the issue associated with non-regenerative relay. Figures 5A and 5C correspond to excerpts from Figure 1. In this example, it is assumed that the frequency resource of the signal transmitted from the base station 20 to the terminal station 40b and the frequency resource of the non-regenerative relay signal transmitted from the relay station 30 to the terminal station 40a are offset (or do not overlap).

[0062] The signal to interference plus noise ratio (SINR) of the terminal station 40b is calculated as the ratio (=P / (I+N)) of the interference power level I and noise level N to the power level P of the signal received by the terminal station 40. Note that in the present disclosure, the unit of each level may be decibel-milliwatts (dBm), dB, or the like.

[0063] As shown in Figure 5A, if relay station 30 in system 1 is not performing non-regenerative relay (or does not exist at all), terminal station 40b will not experience any interference, and the received SINR of terminal station 40b will be as shown in Figure 5B.

[0064] On the other hand, when relay station 30 in system 1 performs unregenerative repeating, as shown in Fig. 5C, for example, unregenerative repeating in DL amplifies not only the repeatered signal but also unwanted signals such as noise, so as shown in Fig. 5D, interference occurs due to the unregenerative repeat signal in a frequency region outside the frequency resource of the unregenerative repeat signal for terminal station 40a. Therefore, the received SINR of terminal station 40b in Fig. 5C is smaller than that in the case of Fig. 5A.

[0065] As explained above, terminal station 40b that does not use relaying may be subject to interference from non-regenerative relaying that uses relay station 30, resulting in a deterioration in communication quality and a drop in communication throughput.

[0066] Therefore, the present inventors came up with the idea of ​​stopping / resuming non-regenerative relaying at a relay station that can be a relatively large source of interference to terminal stations that do not use non-regenerative relaying. In one aspect of the present disclosure, in non-regenerative relaying on a downlink line, terminal stations (without non-regenerative relaying) that are at risk of interference are identified based on the transmission spectrum mask of the relay station. Then, if interference occurs at the terminal station (for example, if the received SINR of the terminal station exceeds an allowable value), the non-regenerative relaying is stopped. Furthermore, if it is determined that interference will not occur at the terminal station even if non-regenerative relaying is resumed while it is stopped, the non-regenerative relaying is resumed.

[0067] <Operation Example> An example of the operation of each device according to an embodiment of the present disclosure will be described below. The communication method (wireless communication method, control method) described below may be applied to the system 1 described above.

[0068] In the following description of the present disclosure, reference numerals may be omitted. For example, the control device in the following description may refer to the control device 10.

[0069] In the following explanations and drawings, the base station may be abbreviated as BS, the relay station as R, and the terminal station as UE. Also, the subscripts ☐ and ☐ indicate that the parameters are related to reception (received signals). ＲＸ Also, the subscript "" is used to indicate that the parameter is related to transmission (transmission signal).ＴＸ It is sometimes expressed with the addition of .

[0070] In the following description, each device may be interchangeably read as one or more functional blocks (e.g., control unit 110, communication unit 120) or hardware configurations (e.g., RF circuit 520, processor 530) within the device.

[0071] In one embodiment of the present disclosure, the control device 10 / base station 20 / relay station 30 may select whether or not the relay station 30 functions as a relay station (performs non-regenerative relay) for a certain terminal station 40. The relay station 30 may perform non-regenerative relay semi-fixedly / semi-permanently. Note that the relay station 30 may stop the non-regenerative relay when an instruction to stop the non-regenerative relay is received from the base station 20 / control device 10, or when a certain time has elapsed since the start of the non-regenerative relay or from a specific timing. Note that the term "stop" may be interpreted interchangeably as "completion," "end," etc.

[0072] (First Control Flow) Fig. 6 is a diagram illustrating an example of a first control flow according to an embodiment of the present disclosure. In the first control flow, the control device determines whether to stop / resume non-regenerative relay.

[0073] In step S101, the control device identifies a terminal station (terminal station 40b) that may be subject to interference when the relay station performs non-regenerative relay. ｉ (i is, for example, an integer) may be determined based on information about the received SINR at the timing when the non-regenerative relay is performed.

[0074] The information about the received SINR is, for example, ｉ The worst value γ of the received SINR (which may be referred to as the expected received SINR) estimated (assumed) for ＲＸ，ｍｉｎ ＵＥｉ The control device may select terminal stations that are likely to interfere with the relay station when the relay station performs non-regenerative relaying, as γ ＲＸ，ｍｉｎ ＵＥｉ ≦γ ＲＥＱ ＵＥｉ A terminal station UE that satisfies ｉ It may be determined that

[0075] where γ ＲＥＱＵＥｉ is a threshold for decision and may be called the required SINR. ＲＥＱ ＵＥｉ is UE ｉ may be different for different UEs ｉ γ ＲＥＱ ＵＥｉ is UE ｉ Location of UE ｉ The estimated received signal power of the terminal station UE, the estimated received signal quality of the base station ｉ The available MCS may be determined based on at least one of the following: a Modulation and Coding Scheme (MCS) available for communication with the terminal station UE using Downlink Control Information (DCI) for a Physical Downlink Shared Channel (PDSCH), and the like. ｉ The MCS may be an MCS corresponding to a particular (e.g., maximum or minimum) or desired coding rate that can be specified.

[0076] In other words, the terminal station where the above-mentioned interference is a concern may be a terminal station where the worst-case expected received SINR of the signal from the base station when non-regenerative relaying is performed is equal to or less than a threshold value (required SINR).

[0077] gamma ＲＸ，ｍｉｎ ＵＥｉ is the terminal station UE ｉ may be calculated based on at least one of the expected received signal power, the expected received interference power, the expected noise power, etc. ＲＸ，ｍｉｎ ＵＥｉ may be calculated using the following equations 1 and 2.

[0078]

[0079] Here, P ＴＸ ＢＳ is the terminal station UE in the base station ｉ the transmission power of the signal to ＢＳ→ＵＥｉ，ｐｒｅ is the base station and the terminal station UE ｉ The estimated propagation loss (path loss) betweenＩＮ，ｍａｘ ＵＥｉ is the terminal station UE ｉ is the maximum value of the expected interference noise power due to the non-regenerative repeat signal in ＴＸ，ｍａｘ Ｒ is the maximum transmission power at the relay station, L ＳＩ Ｒ is the propagation loss between the receiving antenna and the transmitting antenna of the relay station, D ＵＥｉ is the value obtained from a specific spectral mask of the unregenerated repeat signal, P Ｎ ＵＥｉ is the terminal station UE ｉ is the noise power.

[0080] That is, in Equation 1, P ＴＸ ＢＳ -L ＢＳ→ＵＥｉ，ｐｒｅ is the terminal station UE ｉ in terms of the expected received signal power, P ＴＸ，ｍａｘ Ｒ -L ＳＩ Ｒ -D ＵＥｉ is the terminal station UE ｉ In relation to the expected received interference power (when the propagation loss is minimum and the relay power is maximum), P Ｎ ＵＥｉ is the terminal station UE ｉ This is related to the assumed noise power of

[0081] FIG. 7 shows the ＲＸ，ｍｉｎ ＵＥｉ 1 is a diagram illustrating an example of parameters for calculating the terminal station UE. ｉ The expected received signal from the base station and the spectral mask of the unregenerated relay signal from the relay station are shown in Equations 1 and 2. ＲＸ，ｍｉｎ ＵＥｉ It can be seen that can be derived.

[0082] FIG. 8 shows the D ＵＥｉ The transmission spectrum mask of the unregenerative repeating signal varies depending on the frequency. This is because the power of the unregenerative repeating signal weakens as it moves away from the frequency resource used for unregenerative repeating. ＵＥｉ may indicate how weak the power of the unregenerated repeated signal is depending on the frequency.

[0083] A certain resource block b and a resource block b used for non-regenerative relay Ｒ→ＵＥ（Ｒ） The frequency difference between Δf(b, b Ｒ→ＵＥ（Ｒ） ), then Δf(b, b Ｒ→ＵＥ（Ｒ） ) = f ｃ (b)-f ｃ (b Ｒ→ＵＥ（Ｒ） ) where f ｃ (b) is the center frequency of resource block b, and f ｃ (b Ｒ→ＵＥ（Ｒ） ) is resource block b Ｒ→ＵＥ（Ｒ） is the center frequency of

[0084] Shown in Figure 8 is D ＵＥｉ =D ＵＥｉ (Δf(b, b Ｒ→ＵＥ（Ｒ） )) and D ＵＥｉ (Δf(b Ｒ→ＵＥ（Ｒ） , b Ｒ→ＵＥ（Ｒ） )) = D ＵＥｉ (0) = 0.

[0085] The control device is P ＴＸ ＢＳ , L ＢＳ→ＵＥｉ，ｐｒｅ and P ＴＸ，ｍａｘ Ｒ The control device may know (pre-store) the values ​​of P ＴＸ ＢＳ may be determined based on a report from the base station (e.g., may be determined to be a reported value or a value indicated by reported information). ＳＩ Ｒ / P ＴＸ，ｍａｘ ＢＳ may be determined based on reports from the relay stations (e.g., may be determined to be a reported value or a value indicated by reported information). ＢＳ→ＵＥｉ，ｐｒｅ is the past measurement result of the base station / terminal station (specifically, the L ＢＳ→ＵＥｉ ) may be derived from

[0086] The control device is D ＵＥｉ The specific spectrum mask may be determined to be a representative spectrum mask, or the terminal station UE ｉThe control device may determine whether the P Ｎ ＵＥｉ may be determined to be a representative (or specific) noise power, or ｉ The determination may be made based on a report of measurement results from P. The representative spectral mask or power may be predetermined in a standard (for example, it may be a required spectral mask or required power value in the standard). ＩＮ ＵＥｉ is a plurality of terminal stations UE ｉ The same for (e.g., P ＩＮ ＵＥ０ =P ＩＮ ＵＥ１ ) or may be different for each terminal station.

[0087] In step S102, the control device instructs the relay station to perform non-regenerative relaying by semi-fixed slot allocation in communication with a specific terminal station (terminal station 40a, which may also be referred to as UE(R)). This instruction may include information (setting information) regarding at least one of the frequency resources (subcarriers, resource blocks, etc.) to be used, time resources (e.g., timing, period, offset relative to a certain time, etc.), and power resources (e.g., relay power value, absolute value or relative value relative to a certain power).

[0088] In step S103, the relay station instructed in step S102 performs relay communication with the specific terminal station by non-regenerative relay.

[0089] The relay station may be a terminal station UE that is identified as being at risk of interference in step S101. ｉ The base station (or the control device) may notify the terminal station UE of the information relating to the above (for example, via a control line). ｉ The information may include information for identifying the UE (e.g., a UE identifier, a Radio Network Temporary Identifier (RNTI)), or ｉ For example, the relay station may include information instructing the UE to measure the path loss of theｉ When the base station ( / control device) notifies the terminal station UE of the information instructing it to measure the propagation loss of ｉ L, which is the propagation loss between the ＵＥｉ→Ｒ may be measured and reported to the base station ( / controller).

[0090] In step S104, the control device determines whether a terminal station UE receives (or can receive) a signal from the base station at the same timing as the non-regenerative relay from the relay station. ｉ γ, which is the expected received SINR at ＲＸ， ＵＥｉ In addition, the terminal station UE ｉ is different from the specific terminal station that is the direct target of non-regenerative relay.

[0091] gamma ＲＸ ＵＥｉ is the terminal station UE ｉ may be calculated based on at least one of the expected received signal power, the expected received interference power, the expected noise power, etc. ＲＸ ＵＥｉ may be calculated based on the following equation 3-6.

[0092]

[0093] Here, L ＢＳ→ＵＥｉ is the base station and the terminal station UE ｉ Path loss between ＩＮ ＵＥｉ is the terminal station UE ｉ is the expected interference noise power due to the non-regenerative repeat signal in ＴＸ Ｒ is the transmission power at the relay station, L Ｒ→ＵＥｉ is the relay station and the terminal station UE ｉ The propagation loss between ＴＸ Ｒ is from the relay station to the terminal station UE ｉ is the SINR of the transmitted signal to ＲＸ Ｒ is the SINR of the received signal from the base station at the relay station, and NF ＴＸ Ｒis the noise figure (NF) of the relay station. The noise figure may correspond to the ratio of the output SNR to the input signal to noise ratio (SNR) (=input SNR / output SNR). ＢＳ→Ｒ is the propagation loss between the base station and the relay station, P Ｎ Ｒ is the noise power at the relay station.

[0094] FIG. 9 shows the ＲＸ ＵＥｉ 1 is a diagram illustrating an example of parameters for calculating the terminal station UE. ｉ The received signal from the base station (directly) and the received signal of the signal relayed non-regeneratively from the relay station to the specific terminal station are shown in Equation 3-6. ＲＸ ＵＥｉ It can be seen that can be derived.

[0095] The base station calculates the propagation loss L from the relay station to the base station based on the reference signal (RS) transmitted from the relay station. Ｒ→ＢＳ The base station may measure the ｉ Based on the reference signal transmitted from the relay station, the propagation loss L from the relay station to the base station is calculated. ＵＥｉ→ＢＳ The base station may report information about these measurements to the control device.

[0096] The relay station is a terminal station UE. ｉ Based on the reference signal transmitted from ｉ Path loss L from the relay station ＵＥｉ→Ｒ The relay station may report information about the measurement result to the control device, either via the base station or not.

[0097] When TDM is used, L ＢＳ→Ｒ =L Ｒ→ＢＳ and L ＢＳ→ＵＥｉ =L ＵＥｉ→ＢＳ and L Ｒ→ＵＥｉ =L ＵＥｉ→Ｒ In this case, the control device may assume that the L Ｒ→ＢＳ , L ＵＥｉ→ＢＳ， L ＵＥｉ→ＲBased on the information about ＢＳ→Ｒ , L ＢＳ→ＵＥｉ， L Ｒ→ＵＥｉ may be derived.

[0098] The control device controls the relay station / terminal station UE via the base station. ｉ The RS configuration information may include information such as information on RBs to be measured and transmission timing of the RS (for example, a period, a time offset from a certain timing).

[0099] In addition, the terminal station UE ｉ The RS configuration information notified to the terminal station UE may also be notified to the relay station. ｉ The RS transmitted from the can be properly received.

[0100] The control device is P ＴＸ Ｒ may be determined based on a report from the relay station (e.g., may be determined to be a reported value or a value indicated by reported information). Ｎ Ｒ 、 NF ＴＸ Ｒ The representative values ​​may be predetermined in the standard (for example, may be required values ​​in the standard). Ｎ Ｒ The terminal station UE ｉ The decision may be made based on reports of measurement results from the

[0101] In step S104, the control device ｉ γ is the desired SINR of the received signal from the base station ＤＥＳＩＲＥＤ ＵＥｉ For example, the control device calculates the ｉ Based on the Modulation and Coding Scheme (MCS) used for communication with ＤＥＳＩＲＥＤ ＵＥｉThe control device may be notified of information about the MCS from the base station. The information about the MCS may be transmitted to the terminal station UE using DCI for the PDSCH. ｉ The MCS (or MCS index) may be specified in the

[0102] In step S105, the control device calculates γ ＲＸ， ＵＥｉ and γ ＤＥＳＩＲＥＤ ＵＥｉ For example, the control device may determine whether to stop the non-regenerative relay of the relay station to the specific terminal station based on the stop condition (for example, γ ＲＸ， ＵＥｉ ≦γ ＤＥＳＩＲＥＤ ＵＥｉ +M ０ ＵＥｉ ) is satisfied, it may be determined that the non-regenerative relay of the relay station is stopped. ０ ＵＥｉ is the terminal station UE ｉ The margin may be a margin (first margin) for a stop condition for the .times. ...

[0103] If it is determined that the non-regenerative relay of the relay station is to be stopped (step S105-Yes), in step S106, the control device ｉ The relay station may notify the terminal station of the stop of non-regenerative repeating for the particular terminal station. In response to the notification of the stop of non-regenerative repeating, the relay station may stop the corresponding non-regenerative repeating.

[0104] In step S107, the control device determines whether the terminal station UE will perform non-regenerative relay if the relay station that has stopped non-regenerative relay in step S106 performs non-regenerative relay. ｉ γ, which is the expected received SINR at ＲＸ， ＵＥｉ In addition, the control device calculates the terminal station UE. ｉ γ is the desired SINR of the received signal from the base station ＤＥＳＩＲＥＤ ＵＥｉThese calculations may be performed in the same manner as in step S104.

[0105] In step S108, the control device calculates γ ＲＸ， ＵＥｉ and γ ＤＥＳＩＲＥＤ ＵＥｉ For example, the control device may determine whether to resume non-regenerative relaying of the relay station to the specific terminal station based on the resumption condition γ ＲＸ， ＵＥｉ ≧γ ＤＥＳＩＲＥＤ ＵＥｉ +M １ ＵＥｉ If M is satisfied, it may be determined that the non-regenerative relaying of the relay station is resumed. １ ＵＥｉ is the terminal station UE ｉ It may be a margin (first margin) for the restart condition for M, and may correspond to at least one of a positive value, 0, and a negative value. １ ＵＥｉ is M ０ ＵＥｉ It may be larger, the same, or smaller.

[0106] M ０ ＵＥｉ , M １ ＵＥｉ The above-mentioned factors include the priority / traffic volume of communication for the specific terminal station, the location of the specific terminal station, the terminal station UE, etc. ｉ Priority of communication / traffic volume for terminal station UE ｉ For example, based on at least one of these, M ０ ＵＥｉ and M １ ＵＥｉ The magnitude relationship between the two may be determined.

[0107] If it is determined that the non-regenerative relay of the relay station is to be resumed (step S108—Yes), the control device ｉ The relay station may notify the restart of non-regenerative relay for the specific terminal station. In response to the notification of the restart of non-regenerative relay, the relay station may restart the corresponding non-regenerative relay (return to step S103).

[0108] In addition, the relay station 30 may stop the non-regenerative relay when it receives an instruction to stop the non-regenerative relay from the base station 20 / control device 10, separate from the above flow, or when a certain amount of time has elapsed since the non-regenerative relay started or from a specific timing.

[0109] In the present disclosure, the stop condition may be referred to as a first condition, and the restart condition may be referred to as a second condition. Note that the stop condition / restart condition may be defined in advance in a standard, may be notified by another device (e.g., a base station or a node of an NF), or may be determined based on its own capabilities.

[0110] According to the first control flow described above, the control device can appropriately control the stopping / restarting of non-regenerative repeating in consideration of interference at another terminal station caused by non-regenerative repeating at a certain terminal station.

[0111] (Second Control Flow) Figure 10 is a diagram illustrating an example of a second control flow according to an embodiment of the present disclosure. The second control flow differs from the first control flow in that the relay station itself determines whether to stop or resume non-regenerative relaying. Below, steps that may be the same as those in the first control flow will not be described repeatedly. For example, steps S201-S203 may be the same as steps S101-S103, respectively.

[0112] In step S204, the relay station ｉ γ, which is the expected received SINR at ＲＸ， ＵＥｉ For example, γ ＲＸ ＵＥｉ may be calculated based on the following equation 3-6 above: ＲＸ ＵＥｉ The acquisition of information used to calculate is described below.

[0113] The control device is P ＴＸ ＢＳ , the derived L ＢＳ→Ｒ and L ＢＳ→ＵＥｉ , the calculated γ ＤＥＳＩＲＥＤ ＵＥｉ, etc. may be notified to the relay station. It is not necessary to notify all of these pieces of information, and for example, some of the information may be stored in the relay station in advance.

[0114] The base station calculates the propagation loss L from the relay station to the base station based on the reference signal transmitted from the relay station. Ｒ→ＢＳ The base station may measure the ｉ Based on the reference signal transmitted from the relay station, the propagation loss L from the relay station to the base station is calculated. ＵＥ→ＢＳ The base station may report information about these measurements to the control device.

[0115] In addition, γ ＲＸ Ｒ may be calculated based on Equation 6, or may be measured based on a notification signal / reference signal from the control device (base station).

[0116] The relay station is P Ｎ ＵＥｉ 、 P Ｎ Ｒ 、 NF ＴＸ Ｒ The control device may determine that each of the above values ​​is a representative value (or a specific value). The representative value may be predetermined in a standard (for example, a required value in the standard). Ｎ Ｒ The terminal station UE ｉ The decision may be made based on reports of measurement results from the

[0117] The relay station is L Ｒ→ＵＥｉ =L ＵＥｉ→Ｒ Assuming that ＵＥｉ→Ｒ From L Ｒ→ＵＥｉ may be derived.

[0118] The relay station calculates γ based on the value notified by the control device described above, the representative value, the value measured / derived by itself, etc. ＲＸ， ＵＥｉ Calculate.

[0119] In step S205, the relay station uses the γ ＲＸ， ＵＥｉ and γ ＤＥＳＩＲＥＤＵＥｉ For example, the relay station may determine whether to stop non-regenerative relay for the specific terminal station based on the stop condition γ ＲＸ， ＵＥｉ ≦γ ＤＥＳＩＲＥＤ ＵＥｉ +M ０ ＵＥｉ If the condition M is satisfied, it may be determined that the non-regenerative relay of the relay station is to be stopped. ０ ＵＥｉ may be notified from the control device or may be stored in the relay station in advance.

[0120] If it is determined that the non-regenerative relay of the relay station is to be stopped (step S205-Yes), in step S206, the relay station stops the non-regenerative relay for the specific terminal station. ｉ The control device may notify the terminal station UE of the stop of non-regenerative repeating for the particular terminal station. Based on the notification of the stop of non-regenerative repeating, the control device may update / control the allocation of frequency resources related to non-regenerative repeating for the relay station. For example, the control device may allocate frequency resources to be used for non-regenerative repeating for the relay station to the terminal station UE. ｉ The relay station may then change the frequency resource to one that is expected to reduce interference with the specific terminal station, and return to step S102 to transmit an instruction to the relay station to perform non-regenerative relay using the changed frequency resource in communication with the specific terminal station.

[0121] In step S207, the relay station determines the terminal station UE if the relay station performs non-regenerative relay. ｉ γ, which is the expected received SINR at ＲＸ， ＵＥｉ In addition, the relay station calculates the terminal station UE ｉ γ is the desired SINR of the received signal from the base station ＤＥＳＩＲＥＤ ＵＥｉ These calculations may be performed in the same manner as in step S204.

[0122] In step S208, the relay station uses the γ ＲＸ， ＵＥｉ and γ ＤＥＳＩＲＥＤ ＵＥｉFor example, the relay station may determine whether to resume non-regenerative relaying of the relay station to the specific terminal station based on the resumption condition γ ＲＸ， ＵＥｉ ≧γ ＤＥＳＩＲＥＤ ＵＥｉ +M １ ＵＥｉ If M is satisfied, it may be determined that the non-regenerative relay is to be resumed. １ ＵＥｉ may be notified from the control device or may be stored in the relay station in advance.

[0123] If it is determined that non-regenerative relaying is to be resumed (step S208—Yes), the relay station may resume non-regenerative relaying (return to step S203). ｉ The terminal station may be notified of the resumption of non-regenerative relay for the specific terminal station.

[0124] According to the second control flow described above, the relay station can appropriately control the suspension / resumption of non-regenerative relaying in consideration of interference at another terminal station caused by non-regenerative relaying to the terminal station.

[0125] (Third Control Flow) Figure 11 is a diagram illustrating an example of a third control flow according to an embodiment of the present disclosure. The third control flow differs from the first and second control flows in that it determines whether to stop or resume non-regenerative relaying based on reception quality information from the terminal station. Below, steps that may be the same as those in the first control flow will not be described repeatedly. For example, steps S301-S303 and S305-S306 may be the same as steps S101-S103 and S105-S106, respectively.

[0126] In addition, based on the second control flow, the control device-related processing in Figure 11 may be replaced with relay station-related processing, and the relay station may be configured to determine whether to stop / resume non-regenerative relaying based on reception quality information from the terminal station.

[0127] In step S304, the control device ｉ γ, the received SINR at ＲＸ， ＵＥｉ The terminal station UE ｉThe calculation is based on the reception quality information reported by

[0128] For example, when the reception quality information is SS-SINR / CSI-SINR, the value reported as SS-SINR / CSI-SINR may be an integer value between 0 and 127. The base station may also specify the measured quality based on the SS-SINR measurement report mapping shown in FIG. 12 (the same as Table 10.1.16.1-1 of 3GPP TS 38.133). For example, when SS-SINR=0 is reported, the base station may ... SINR (=γ ＲＸ， ＵＥｉ ) may be determined to be less than −23 dB.

[0129] In addition, γ ＲＸ， ＵＥｉ For example, if SS-SINR=0 is reported, the base station may calculate the measured SINR (=γ ＲＸ， ＵＥｉ ) = -23 dB.

[0130] The above numbers such as "127" and "-23" may be replaced with other numbers.

[0131] The reception quality information may include at least one of received power (e.g., Reference Signal Received Power (RSRP)), reception quality (e.g., Reference Signal Received Quality (RSRQ), SINR, SNR), signal strength (e.g., Received Signal Strength Indicator (RSSI)), channel state information (Channel State Information Reference Signal (CSI)), link quality indicator (Link Quality Indicator (LQI)), etc.

[0132] In step S304, similarly to step S104, the control device ｉ γ is the desired SINR of the received signal from the base station ＤＥＳＩＲＥＤ ＵＥｉ Calculate.

[0133] In step S307, the control device determines whether the terminal station UE will perform non-regenerative relay if the relay station that has stopped non-regenerative relay in step S306 performs non-regenerative relay. ｉ γ, which is the expected received SINR at ＲＸ， ＵＥｉ，１ Calculate γ ＲＸ ＵＥｉ，１ is the terminal station UE ｉ may be calculated based on at least one of the expected received signal power, the expected received interference power, the expected noise power, etc. ＲＸ ＵＥｉ，１ may be calculated based on the following equations 7-8:

[0134]

[0135] where γ ＲＸ ＵＥｉ，０ is the terminal station UE at the timing when non-regenerative relay is not used (or non-regenerative relay is not performed). ｉ In step S307, the control device ｉ γ, the received SINR at ＲＸ， ＵＥｉ，０ Similarly to step S304, ｉ It is also possible to calculate the γ in Equation 7 based on the reception quality information reported from ＲＸ ＵＥｉ，０ and γ in Eq. ＲＸ ＵＥｉ，０ The measurement timings may be the same or different. For example, γ in Equation 8 ＲＸ ＵＥｉ，０ The terminal station UE immediately (or at the beginning) after the non-regenerative relay is stopped in step S306. ｉ Alternatively, the γ in Equation 7 may be calculated based on the reception quality information reported from ＲＸ ＵＥｉ，０ may be calculated based on reception quality information reported after the reception quality information described above for Equation 8. ＲＸ， ＵＥｉ may be the value calculated in step S304. Ｒ→ＵＥｉ is the relay station's non-regenerative relay ｉis the expected received interference power (amount of interference) that

[0136] FIG. 13 is a diagram of the I Ｒ→ＵＥｉ 1 is a diagram illustrating an example of parameters for calculating the terminal station UE. ｉ , the (direct) received signal from the base station and the received signal of the signal that is non-regeneratively relayed from the relay station to the specific terminal station are shown. ＲＸ ＵＥｉ，０ When measuring the signal I, there is no received signal of the signal that is non-regeneratively relayed from the relay station to the specific terminal station. Ｒ→ＵＥｉ It can be seen that can be derived.

[0137] FIG. 14 shows the relationship between γ ＲＸ ＵＥｉ，１ 1 is a diagram illustrating an example of parameters for calculating the terminal station UE. ｉ The received signal from the base station (directly) and the received signal of the signal relayed non-regeneratively from the relay station to the specific terminal station are shown in Equation 7-8. ＲＸ ＵＥｉ，１ It can be seen that can be derived.

[0138] The control device also ｉ γ is the desired SINR of the received signal from the base station ＤＥＳＩＲＥＤ ＵＥｉ This calculation may be performed in the same manner as in step S304.

[0139] In step S308, the control device calculates γ ＲＸ， ＵＥｉ，１ and γ ＤＥＳＩＲＥＤ ＵＥｉ For example, the control device may determine whether to resume non-regenerative relaying of the relay station to the specific terminal station based on the resumption condition γ ＲＸ， ＵＥｉ，１ ≧γ ＤＥＳＩＲＥＤ ＵＥｉ +M １ ＵＥｉ If the condition is satisfied, it may be determined that the non-regenerative relaying of the relay station is resumed.

[0140] If it is determined that the non-regenerative relay of the relay station is to be resumed (step S308—Yes), the control deviceｉ The relay station may notify the restart of non-regenerative relay for the specific terminal station. In response to the notification of the restart of non-regenerative relay, the relay station may restart the corresponding non-regenerative relay (return to step S303).

[0141] According to the third control flow described above, the control device can appropriately control the stopping / restarting of non-regenerative repeating in consideration of interference at another terminal station caused by non-regenerative repeating at a certain terminal station.

[0142] (Variations of Stop / Restart Judgment) As shown in steps S105, S108, etc., the nth (n is an integer) judgment result regarding the stop / restart of non-regenerative relaying at the relay station is used as D ＵＥｉ Ｒ If (n)∈{0, 1} (for example, 0 = stop, 1 = resume), there are the following variations of decisions: (1) apply (use) the result of each time as it is, (2) moving average, (3) switch and stay, (4) actually apply if the number of times the same decision is made in a certain period of time exceeds a threshold.

[0143] In the case of (1) above, D ＵＥｉ Ｒ (n) = D ＵＥｉ Ｒ (n).

[0144] In the case of (2) above, for example, the moving average window W ＭＡ (Window length = L ｗ ) to calculate the moving average. In this case, D ＵＥｉ Ｒ (n) = W ＭＡ (D ＵＥｉ Ｒ (n-L ｗ +1:n), and W ＭＡ (D ＵＥｉ Ｒ (n-L ｗ +1:n)) may be calculated using the following formula 9: D ＵＥｉ Ｒ (n-L ｗ +1:n) is D ＵＥｉ Ｒ (n-L ｗ +1), ..., D ＵＥｉ Ｒ It may also mean (n).

[0145]

[0146] In addition, a ｉ is a weight, which may vary based on the time elapsed since the decision. ｉ The larger i (the closer it is to n), the larger the value may be. In this case, more recent judgment results can be treated more importantly. Note that "0.5" in Equation 9 may be another real number value.

[0147] In the case of the above (3), as shown in the following formula 10, ｓｓ The result of the decision is D ＵＥｉ Ｒ (n-L ｓｓ : n-1) are all current judgment D ＵＥｉ Ｒ If it is different from (n), the next decision D ＵＥｉ Ｒ (n+1) is forced to the past L ｓｓ In other words, the nth determination temporarily switches between stopping and restarting non-regenerative relay, but the n+1th determination returns it to the previous state.

[0148]

[0149] In the case of (4) above, if the same judgment result (a judgment that changes from the current state) occurs more than the threshold X times within the period T, the judgment result is actually treated as valid, and if not, the non-regenerative relay state is maintained.

[0150] Which of the above (1) to (4) is used, and L ｗ , "other real values", the values ​​of Lss, T, X, etc. may be predetermined, may be provided by another device, or may be determined based on the communication quality of the mobile station, etc.

[0151] (Variations of Control Flow) In the above control flow, a case where there is one relay station and non-regenerative relay is transmitted to only one terminal station is illustrated, but the scope of application of the present disclosure is not limited to this. The first, second, and third control flows described above can be modified and applied to cases where there are multiple relay stations, where non-regenerative relay is transmitted from one relay station to multiple terminal stations, and so on.

[0152] For example, if there are multiple relay stations, in step S101, ＩＮ，ｍａｘ ＵＥｉ may be calculated using the following Equation 11 instead of Equation 2.

[0153]

[0154] Here, N Ｒ is the number of relay stations that are going to perform non-regenerative relaying, P ＴＸ，ｍａｘ Ｒｊ is relay station R ｊ The maximum value of the transmission power in ＳＩ Ｒｊ is relay station R ｊ Path loss between the receiving antenna and the transmitting antenna, D ＵＥｉ Ｒｊ is relay station R ｊ is a value obtained from a specific spectral mask of the unregenerated repeat signal of P ＴＸ，ｍａｘ Ｒｊ , L ＳＩ Ｒｊ , D ＵＥｉ Ｒｊ are the same as those described in the first control flow. ＴＸ，ｍａｘ Ｒ , L ＳＩ Ｒ , D ＵＥｉ may be obtained / identified in the same manner.

[0155] FIG. 15 shows the relay station R １ and R ２ γ when trying to perform non-regenerative relay ＲＸ，ｍｉｎ ＵＥｉ 1 is a diagram illustrating an example of parameters for calculating P ＴＸ，ｍａｘ Ｒ１ =P ＴＸ，ｍａｘ Ｒ２ =P ＴＸ，ｍａｘ Ｒ From equations 1 and 11, γ ＲＸ，ｍｉｎ ＵＥｉ It can be seen that can be derived.

[0156] Note that multiple relay stations may perform non-regenerative relay for the same terminal station. For example, multiple relay stations may use the same frequency to perform non-regenerative relay for the same terminal station.

[0157] If there are multiple relay stations, the relay station in step S102 and subsequent steps may be replaced with each of the multiple relay stations. For example, in steps S102 and S103, the control device instructs the multiple relay stations to perform non-regenerative relay, and the multiple relay stations perform non-regenerative relay.

[0158] If there are multiple relay stations, in steps S104 and S107, ＩＮ ＵＥｉ may be calculated using the following equations 12-14 instead of equations 4-6.

[0159]

[0160] Here, P ＴＸ Ｒｊ is relay station R ｊ transmission power at L Ｒｊ→ＵＥｉ is relay station R ｊ and the terminal station UE ｉ The propagation loss between ＴＸ Ｒｊ is relay station R ｊ to the terminal station UE ｉ is the SINR of the transmitted signal to ＲＸ Ｒｊ is relay station R ｊ is the SINR of the received signal from the base station at NF ＴＸ Ｒｊ is relay station R ｊ NF of L ＢＳ→Ｒｊ is the base station and relay station R ｊ The propagation loss between Ｎ Ｒｊ is relay station R ｊ is the noise power at

[0161] FIG. 16 shows the relay station R １ and R ２ γ when non-regenerative relay is performed ＲＸ ＵＥｉ γ is calculated from Equations 3, 12-14. ＲＸ ＵＥｉ It can be seen that can be derived.

[0162] In step S106, step S108-Yes, etc., the stop / restart of non-regenerative relay is Ｒ All relay stations may be targeted, or N Ｒ Alternatively, only a specific relay station among the relay stations may be targeted. In the latter case, non-regenerative relay communication with stations other than the specific relay station can be continued, and the communication quality of the terminal station receiving the non-regenerative relay communication can be ensured. For example, Ｒ Among the relay stations, the target of non-regenerative relay stop is determined based on the stop condition (for example, γ ＲＸ， ＵＥｉ ≦γ ＤＥＳＩＲＥＤ ＵＥｉ +M ０ ＵＥｉ ) is no longer satisfied, ｉ The selected relay station may be selected in descending order of interference to γ ＲＸ， ＵＥｉ (excluding from the

[0163] Furthermore, those skilled in the art will naturally understand that even when non-regenerative relays are transmitted from one relay station to multiple terminal stations, a similar control flow can be realized by taking into account each transmission signal, etc., as in the case of multiple relay stations described above.

[0164] According to the variations of the control flow described above, the control device / relay station can appropriately control the stopping / restarting of non-regenerative relaying, taking into account interference at other terminal stations caused by non-regenerative relaying at multiple relay stations / terminal stations.

[0165] <Supplementary Information> In the present disclosure, the non-regenerative relay that is stopped / resumed is assumed to be downlink communication, but is not limited to this, and only uplink communication may be stopped / resumed, or both uplink communication and downlink communication may be stopped / resumed.

[0166] In the present disclosure, the frequency resources of the signal transmitted from the base station 20 to the terminal station 40b and the frequency resources of the non-regenerative relay signal transmitted from the relay station 30 to the terminal station 40a may not overlap, or may overlap partially or completely.

[0167] In the present disclosure, the notification of stopping / resuming non-regenerative relay may be a notification of information that explicitly indicates the stopping / resuming of non-regenerative relay, or may be a notification of information / signal that implicitly indicates the stopping / resuming of non-regenerative relay.

[0168] In the present disclosure, an example has been shown in which the stop / restart of non-regenerative relaying in the above-described control flow is controlled based on SINR, but this is not limiting. The SINR in the above-described control flow may be interpreted as any metric related to received power / received quality / signal strength, CSI, LQI, etc., or a combination thereof.

[0169] In the present disclosure, a measurement result (such as SINR) may correspond to a measurement result in a specific layer (e.g., Layer 1, Layer 3). For example, any measurement result may be interchangeably read as a measurement result labeled Layer 1 (L1-), Layer 3 (L3-), etc.

[0170] In the present disclosure, the terms resource block (RB), subcarrier, resource element, subband, resource block group, physical RB (PRB), common RB (CRB), virtual RB (VRB), resource block set, frequency band, bandwidth, frequency bandwidth, frequency band, frequency range, frequency resource, frequency domain resource, etc. may be read interchangeably.

[0171] The formulas shown in this disclosure may be interchangeably read as formulas in which a predetermined operation (e.g., addition, subtraction, multiplication, or division) is applied to any coefficient / variable / term with any value.Furthermore, the formulas shown in this disclosure may be interchangeably read as formulas in which any coefficient / variable / term has been deleted.

[0172] In the present disclosure, measurements at a base station / relay station / terminal station may be performed based on at least one of a reference signal, a synchronization signal (SS), and a channel. In the present disclosure, even when non-regenerative relaying is stopped / ended, measurements at a base station / relay station / terminal station may be performed (a reference signal / synchronization signal / channel for measurements may also be transmitted).

[0173] As the reference signal, a Downlink Reference Signal (DL-RS), an Uplink Reference Signal (UL-RS), or the like may be used.

[0174] The uplink channel may be a Physical Uplink Shared Channel (PUSCH), a Physical Uplink Control Channel (PUCCH), a Physical Random Access Channel (PRACH), or the like.

[0175] The downlink channel may be a Physical Downlink Shared Channel (PDSCH), a Physical Downlink Control Channel (PDCCH), a Physical Broadcast Channel (PBCH), or the like.

[0176] The DL-RS may be a Channel State Information Reference Signal (CSI-RS), a Demodulation Reference Signal (DMRS), a Positioning Reference Signal (PRS), a Phase Tracking Reference Signal (PTRS), a Cell-specific Reference Signal (CRS), etc.

[0177] Note that CSI-RS may be interchangeably referred to as Non Zero Power (NZP) CSI-RS, NZP CSI-RS for interference measurement, CSI-Interference Measurement (IM), Zero Power (ZP) CSI-RS, etc.

[0178] The UL-RS may be a sounding reference signal (SRS), a demodulation reference signal (DMRS), a PRS, a PTRS, or the like.

[0179] Note that the DMRS may be called a user equipment specific reference signal (UE-specific reference signal), and a different DMRS may be used for each channel (for example, a PUSCH DMRS, a PUCCH DMRS, a PDSCH DMRS, a PDCCH DMRS, a PBCH DMRS, etc. may be used).

[0180] The synchronization signal may be, for example, at least one of a Primary Synchronization Signal (PSS) and a Secondary Synchronization Signal (SSS). A signal block including an SS (PSS, SSS) and a PBCH (and a PBCH DMRS) may be referred to as an SS / PBCH block, an SS Block (SSB), or the like. Note that the SS, SSB, and the like may also be referred to as a reference signal.

[0181] (Application of Each Embodiment) At least one of the above-described embodiments may be applied when a specific condition is met. The specific condition may be defined in a standard or may be notified to any device using higher layer signaling / physical layer signaling.

[0182] Furthermore, at least one of the above-described embodiments may be applied when any device is configured / activated / triggered with specific information related to the above-described embodiment (or performing the operation of the above-described embodiment) by higher layer signaling / physical layer signaling. For example, the specific information may be information indicating that SINR-based non-regenerative relaying stop / resume control is enabled, any RRC parameter for a specific release (e.g., Rel. 18 / 19), etc.

[0183] <Modifications> Note that terms explained in this disclosure and terms necessary for understanding this disclosure may be replaced with terms having the same or similar meanings.

[0184] In the present disclosure, the terms apparatus, circuit, device, section, unit, etc. may be read interchangeably.

[0185] The information, parameters, etc. described in the present disclosure may be expressed using absolute values, relative values ​​from a predetermined value, or other corresponding information. For example, a radio resource may be indicated by a predetermined index.

[0186] The names used for parameters and the like in this disclosure are not limiting in any way, and furthermore, the formulas and the like using these parameters may differ from those explicitly disclosed in this disclosure.

[0187] The information, signals, etc. described in this disclosure may be represented using any of a variety of different technologies. For example, data, instructions, commands, information, signals, bits, symbols, chips, etc. that may be referred to throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, optical fields or photons, or any combination thereof.

[0188] Input and output information, signals, etc. may be stored in a specific location (for example, memory) or may be managed using a management table. Input and output information, signals, etc. may be overwritten, updated, or added. Output information, signals, etc. may be deleted. Input information, signals, etc. may be transmitted to another device.

[0189] Any information described in the present disclosure (e.g., information related to any parameter / variable) may be communicated between any devices in the present disclosure. Furthermore, in the present disclosure, communication of information is not limited to the aspects / embodiments described in the present disclosure, and may be performed using other methods.

[0190] For example, notification of information in the present disclosure may be performed by physical layer signaling (e.g., Downlink Control Information (DCI) and Uplink Control Information (UCI))), higher layer signaling (e.g., Radio Resource Control (RRC) signaling, broadcast information (Master Information Block (MIB) and System Information Block (SIB)), Medium Access Control (MAC) signaling), signaling of a specific interface (e.g., X2 interface, S1 interface, NG interface), other signals / channels (e.g., reference signals), or a combination thereof.

[0191] Note that the physical layer signaling may be referred to as Layer 1 / Layer 2 (L1 / L2) control information (L1 / L2 control signal), L1 control information (L1 control signal), etc. Furthermore, the RRC signaling may be referred to as an RRC message, such as an RRC Connection Setup message or an RRC Connection Reconfiguration message. Furthermore, the MAC signaling may be notified using, for example, a MAC Control Element (CE).

[0192] Furthermore, notification of specified information (e.g., notification that "it is X") is not limited to explicit notification, but may be made implicitly (e.g., by not notifying the specified information or by notifying other information).

[0193] Software shall be construed broadly to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executable files, threads of execution, procedures, functions, etc., whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise.

[0194] Software, instructions, information, etc. may also be transmitted or received over a transmission medium. For example, if software is transmitted from a website, server, or other remote source using wired technologies (such as coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL)), and / or wireless technologies (such as infrared, microwave), these wired and / or wireless technologies are included within the definition of transmission media.

[0195] In the present disclosure, terms such as "Base Station (BS)," "Radio Base Station," "Relay Station," "Fixed Station," "NodeB," "eNB (eNodeB)," "gNB (gNodeB)," "Access Point," "Transmission Point (TP)," "Reception Point (RP)," "Transmission / Reception Point (TRP)," "Panel," "Cell," "Sector," "Cell Group," "Carrier," "Component Carrier," etc. may be used interchangeably.

[0196] In this disclosure, the terms "Mobile Station (MS)," "user terminal," "User Equipment (UE)," "terminal," etc. may be used interchangeably.

[0197] Any device in this disclosure may be an Internet of Things (IoT) device, such as a sensor.

[0198] Any device in the present disclosure may be referred to as a transmitting device, a receiving device, a wireless communication device, etc. Any device in the present disclosure may be a device mounted on a moving object, which is a movable body, or the moving object itself. Examples of such moving objects include, but are not limited to, vehicles, transport vehicles, automobiles, motorcycles, bicycles, connected cars, excavators, bulldozers, wheel loaders, dump trucks, forklifts, trains, buses, handcarts, rickshaws, ships and other watercraft, airplanes, rockets, satellites, drones, multicopters, quadcopters, balloons, and objects mounted thereon. In addition, such moving objects may be autonomous / automatically driven.

[0199] Each aspect / embodiment described in this disclosure may be used alone, in combination, or switched depending on the implementation. Furthermore, the order of the processing procedures, sequences, flowcharts, etc. of each aspect / embodiment described in this disclosure may be changed unless inconsistent. For example, the methods described in this disclosure present elements of various steps using an example order, and are not limited to the particular order presented.

[0200] As used in this disclosure, the phrase "based on" does not mean "based only on," unless expressly stated otherwise. In other words, the phrase "based on" means both "based only on" and "based at least on."

[0201] As used in this disclosure, any reference to an element using a designation such as "first," "second," etc. does not generally limit the quantity or order of those elements. These designations may be used in this disclosure as a convenient method of distinguishing between two or more elements. Thus, a reference to a first and a second element does not imply that only two elements may be employed or that the first element must in some way precede the second element.

[0202] As used in this disclosure, the terms "connected," "coupled," or any variation thereof, refer to any direct or indirect connection or coupling between two or more elements, and may include the presence of one or more intermediate elements between two elements that are "connected" or "coupled" to each other. The coupling or connection between elements may be physical, logical, or a combination thereof. The coupling or connection between elements may be via wired and / or wireless connections.

[0203] In the present disclosure, the term "A and B are different" may mean "A and B are different from each other." The term may also mean "A and B are each different from C." Terms such as "separate" and "coupled" may also be interpreted in the same way as "different."

[0204] When the terms "include," "including," and variations thereof are used in this disclosure, these terms are intended to be inclusive, similar to the term "comprising." Furthermore, when the term "or" is used in this disclosure, it is not intended to be an exclusive or.

[0205] In this disclosure, where articles are added by translation, such as a, an, and the in English, the disclosure may include that the nouns following these articles are in the plural form.

[0206] In the present disclosure, terms such as "decide," "judge," "determine," "select," "calculate," "calculate," "process," "derive," "search," "confirm," "assume," and "expect" may be read interchangeably.

[0207] In the present disclosure, terms such as "less than or equal to," "less than," "greater than," "more than," "equal to," etc. may be interchangeable. Furthermore, in the present disclosure, terms meaning "good," "bad," "big," "small," "high," "low," "fast," "slow," "wide," "narrow," etc. may be interchangeable, not limited to the positive, comparative, and superlative. Furthermore, in the present disclosure, terms meaning "good," "bad," "big," "small," "high," "low," "fast," "slow," "wide," "narrow," etc. may be interchangeable, not limited to the positive, comparative, and superlative, as expressions with "i-th" (i is an arbitrary integer) attached (for example, "highest" may be interchangeable with "i-th highest").

[0208] In this disclosure, the terms "of," "for," "regarding," "related to," "associated with," etc. may be read interchangeably.

[0209] Although the invention according to the present disclosure has been described in detail above, it is clear to those skilled in the art that the invention according to the present disclosure is not limited to the embodiments described in the present disclosure. The description of the present disclosure is for illustrative purposes only and does not impose any limiting meaning on the invention according to the present disclosure.

[0210] <Supplementary Notes> The following inventions are supplementary notes regarding one embodiment of the present disclosure. [Supplementary Note 1] A control device comprising: a control unit that identifies a second terminal station that is concerned about interference due to non-regenerative relaying between a base station and a first terminal station via a relay station; and a communication unit that notifies the relay station of the stop of the non-regenerative relaying when a first condition related to a received signal to interference plus noise ratio (SINR) of a signal received by the second terminal station from the base station is satisfied at a timing when the non-regenerative relaying is performed. [Supplementary Note 2] The control device according to Supplementary Note 1, wherein the control unit identifies the second terminal station based on a worst-case value of the received SINR expected at a timing when the non-regenerative relaying is performed. [Supplementary Note 3] The control device according to Supplementary Note 2, wherein the control unit calculates the worst-case value of the received SINR based on a maximum value of interference plus noise power expected to be caused by the non-regenerative relaying at the second terminal station. [Supplementary Note 4] The control device according to any one of Supplementary Notes 1 to 3, wherein the first condition is based on the expected received SINR at the timing when the non-regenerative relaying is performed, a desired SINR, and a first margin. [Supplementary Note 5] The control device according to Supplementary Note 4, wherein the communication unit notifies the relay station of the resumption of the non-regenerative relaying when the non-regenerative relaying is stopped and a second condition related to the expected received SINR when the non-regenerative relaying is performed is satisfied. [Supplementary Note 6] The control device according to Supplementary Note 5, wherein the second condition is based on the expected received SINR when the non-regenerative relaying is performed, a desired SINR, and a second margin. [Supplementary Note 7] The control device according to any one of Supplementary Notes 4 to 6, wherein the control unit calculates the received SINR based on an expected interference noise power caused by the non-regenerative relaying at the second terminal station. [Supplementary Note 8] The control device according to Supplementary Note 1, wherein the first condition is based on the received SINR calculated based on reception quality information reported from the second terminal station, a desired SINR, and a first margin.[Supplementary Note 9] A relay station having: a communication unit that receives information about a second terminal station that is concerned about interference due to non-regenerative relaying between a base station and a first terminal station via the relay station; and a control unit that decides to stop the non-regenerative relaying when a first condition related to a received signal to interference plus noise ratio (SINR) of a signal received by the second terminal station from the base station is satisfied at the timing when the non-regenerative relaying is performed. [Supplementary Note 10] The relay station according to Supplementary Note 9, wherein the second terminal station is identified based on a worst-case value of the received SINR expected at the timing when the non-regenerative relaying is performed. [Supplementary Note 11] The relay station according to Supplementary Note 10, wherein the worst-case value of the received SINR is calculated based on a maximum value of interference and noise power expected to be caused by the non-regenerative relaying at the second terminal station. [Supplementary Note 12] The relay station according to any one of Supplementary Notes 9 to 11, wherein the first condition is based on the expected received SINR at the timing when the non-regenerative relaying is performed, a desired SINR, and a first margin. [Supplementary Note 13] The relay station according to Supplementary Note 12, wherein the control unit decides to resume the non-regenerative relaying when the non-regenerative relaying is stopped and a second condition related to the expected received SINR when the non-regenerative relaying is performed is satisfied. [Supplementary Note 14] The relay station according to Supplementary Note 13, wherein the second condition is based on the expected received SINR when the non-regenerative relaying is performed, a desired SINR, and a second margin. [Supplementary Note 15] The relay station according to any one of Supplementary Notes 12 to 14, wherein the received SINR is calculated based on expected interference and noise power caused by the non-regenerative relaying at the second terminal station.[Supplementary Note 16] A control method for a control device, comprising: a step of identifying a second terminal station that is concerned about interference due to non-regenerative relay between a base station and a first terminal station via a relay station; and a step of notifying the relay station to stop the non-regenerative relay when a first condition related to a received signal to interference plus noise ratio (SINR) of a signal received by the second terminal station from the base station is satisfied at the timing when the non-regenerative relay is performed.

[0211] This application is based on Japanese Patent Application No. 2023-131050, filed on August 10, 2023, the contents of which are incorporated herein in their entirety.

Claims

1. A control device having: a control unit that identifies a second terminal station for which interference due to non-regenerative relay between a base station and a first terminal station via a relay station is a concern; and a communication unit that notifies the relay station to stop the non-regenerative relay when a first condition related to the received signal to interference plus noise ratio (SINR) of a signal received from the base station by the second terminal station is satisfied at the time when the non-regenerative relay is performed.

2. The control device according to claim 1, wherein the control unit identifies the second terminal station based on the worst-case value of the received SINR assumed at the timing when the non-regenerative relay is performed.

3. The control device according to claim 2, wherein the control unit calculates the worst value of the received SINR based on a maximum value of interference noise power expected to be caused by the non-regenerative relay in the second terminal station.

4. The control device according to claim 1, wherein the first condition is based on the expected received SINR at the timing when the non-regenerative relay is performed, a desired SINR, and a first margin.

5. The control device described in claim 4, wherein the communication unit notifies the relay station of the resumption of the non-regenerative relay when the non-regenerative relay is stopped and when a second condition related to the expected received SINR when the non-regenerative relay is hypothetically performed is satisfied.

6. The control device according to claim 5, wherein the second condition is based on the expected received SINR when the non-regenerative relay is performed, a desired SINR, and a second margin.

7. A control device according to any one of claims 4 to 6, wherein the control unit calculates the received SINR based on an estimated interference plus noise power caused by the non-regenerative relay in the second terminal station.

8. The control device according to claim 1, wherein the first condition is based on the received SINR calculated based on reception quality information reported from the second terminal station, a desired SINR, and a first margin.

9. A relay station having: a communication unit that receives information regarding a second terminal station for which interference due to non-regenerative relay between a base station and a first terminal station via the relay station is a concern; and a control unit that decides to stop the non-regenerative relay when a first condition related to a received signal to interference plus noise ratio (SINR) of a signal received by the second terminal station from the base station is satisfied at the time when the non-regenerative relay is performed.

10. The relay station according to claim 9, wherein the second terminal station is specified based on the worst-case value of the received SINR assumed at the timing when the non-regenerative relay is performed.

11. The relay station according to claim 10, wherein the worst-case received SINR value is calculated based on a maximum value of interference noise power expected to be caused by the non-regenerative relay in the second terminal station.

12. The relay station according to claim 9, wherein the first condition is based on the expected received SINR at the timing when the non-regenerative relay is performed, a desired SINR, and a first margin.

13. The relay station of claim 12, wherein the control unit decides to resume the non-regenerative relay when the non-regenerative relay is stopped and when a second condition related to the expected received SINR when the non-regenerative relay is performed is satisfied.

14. The relay station according to claim 13, wherein the second condition is based on the expected received SINR when the non-regenerative relaying is performed, a desired SINR, and a second margin.

15. A relay station according to any one of claims 12 to 14, wherein the received SINR is calculated based on an estimated interference plus noise power caused by the non-regenerative relay in the second terminal station.

16. A control method for a control device comprising: a step of identifying a second terminal station for which interference due to non-regenerative relay between a base station and a first terminal station via a relay station is a concern; and a step of notifying the relay station to stop the non-regenerative relay when a first condition related to the received signal to interference plus noise ratio (SINR) of a signal received from the base station by the second terminal station is satisfied at the time when the non-regenerative relay is performed.

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