Communication control method and communication node

Abstract

A communication control method according to an aspect of the present invention is used in a wireless communication system. The communication control method includes a step in which a communication node transmits, to an Internet-of-things (IoT) device, a transmission signal composed of a non-modulated continuous wave and a modulated wave that is obtained by modulating a command. Said command includes resource information related to a resource used for transmission from the IoT device to the communication node.

Description

Communication control method and communication node

[0001] The present disclosure relates to a communication control method and a communication node.

[0002] In recent years, the Internet of Things (IoT) has been attracting attention as a wireless communication technology. As more and more "things" are interconnected, it is expected that production efficiency will improve and life will become more comfortable than ever before.

[0003] Technologies used in IoT include barcodes and radio frequency identifiers (RFIDs), for example. However, barcodes and RFIDs lack interference management schemes, making it difficult for them to support large-scale networks.

[0004] Therefore, the Third Generation Partnership Project (3GPP), a standardization project for mobile communication systems, is studying the feasibility of new IoT technologies. This IoT technology is expected to have a greater number of connections and a higher device density than existing 3GPP IoT technologies. Furthermore, this IoT technology is expected to have lower complexity and power consumption than existing 3GPP LPWA (Low Power Wide Area) technologies such as NB-IoT (Narrow Band-IoT) or LTE-MTC (Long Term Evolution-Machine Type Communication). IoT devices used in this IoT technology are called ambient IoT devices.

[0005] 3GPP TR 38.848 V18.0.0 (2023-09)

[0006] A communication control method according to a first aspect is a communication control method in a wireless communication system, the communication control method including a step of transmitting a transmission signal from a communication node to an IoT device, wherein the transmission signal includes a command including resource information regarding resources to be used for transmission from the IoT device to the communication node.

[0007] A communication node according to a second aspect is a communication node in a wireless communication system, the communication node having a transmitter that transmits a transmission signal to an IoT device, wherein the transmission signal includes a command including resource information related to resources used for transmission from the IoT device to the communication node.

[0008] FIG. 1 is a diagram illustrating an example of the configuration of a wireless communication system according to the first embodiment. FIG. 2 is a diagram illustrating an example of the configuration of a UE (user equipment) according to the first embodiment. FIG. 3 is a diagram illustrating an example of the configuration of a gNB according to the first embodiment. FIG. 4 is a diagram illustrating an example of the configuration of an ambient IoT device according to the first embodiment. FIG. 5 is a diagram illustrating an example of the configuration of a protocol stack related to a user plane according to the first embodiment. FIG. 6 is a diagram illustrating an example of the configuration of a protocol stack related to a control plane according to the first embodiment. FIG. 7 is a diagram illustrating an example of communication according to the first embodiment. FIGS. 8(A) and 8(B) are diagrams illustrating an example of the configuration of a topology according to the first embodiment. FIGS. 9(A) and 9(B) are diagrams illustrating an example of the configuration of a topology according to the first embodiment. FIG. 10 is a diagram illustrating an example of the configuration of a topology according to the first embodiment. FIG. 11 is a diagram illustrating an example of the configuration of "device 1" according to the first embodiment. FIG. 12 is a diagram illustrating an example of the configuration of "device 2a" according to the first embodiment. FIG. 13 is a diagram illustrating a first example of operation according to the first embodiment. FIG. 14 is a diagram illustrating examples of transmission permission slots and transmission permission channels according to the first embodiment. Fig. 15 is a diagram showing a second operation example according to the first embodiment. Fig. 16 is a diagram showing a third operation example according to the first embodiment. Fig. 17 is a diagram showing a Uu protocol stack (topology 2) of a network control C-plane. Fig. 18 is a diagram showing examples of "compact" protocol stacks (topologies 1 and 2) for ambient IoT communication. Fig. 19 is a diagram showing DO-A, DO-DTT, and DT.

[0009] Most existing wireless communication devices use batteries that need to be manually replaced and manually charged. However, powering all IoT devices with batteries would be difficult because it would require not only the cost of the IoT devices themselves but also the maintenance costs for the IoT devices.

[0010] First, the ambient IoT devices described above are envisioned to function as battery-less devices with no energy storage capabilities, in which case the ambient IoT devices function as pure battery-less devices that have no power storage capabilities whatsoever and are completely dependent on the availability of an external energy source.

[0011] Second, ambient IoT devices are envisioned to function as battery devices with limited energy storage, e.g., energy storage that does not require manual replacement and does not require manual charging.

[0012] Specific examples of ambient IoT devices will be described later. As described above, technology using ambient IoT devices is expected to have a higher number of connections, lower complexity, and lower power consumption than existing 3GPP technology. The use of such ambient IoT devices is expected to lead to automation and digitalization in various industries, as well as the development of new markets.

[0013] Hereinafter, a wireless communication system according to an embodiment will be described with reference to the drawings. In the description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. An ambient IoT device is used in the wireless communication system according to the embodiment.

[0014] [First embodiment]

[0015] (Configuration example of wireless communication system) FIG. 1 is a diagram showing a configuration example of a wireless communication system according to the first embodiment. The wireless communication system 1 includes a mobile communication system that is a 5th Generation System (5GS) of the 3GPP standard. In the following, the mobile communication system will be described using 5GS as an example, but an LTE (Long Term Evolution) system may also be applied at least in part. A sixth generation (6G) system or later system may also be applied at least in part as the mobile communication system. Note that the wireless communication system 1 may be a mobile communication system.

[0016] The wireless communication system 1 includes a user equipment (UE) 100, a 5G radio access network (NG-RAN: Next Generation Radio Access Network) 10, a 5G core network (5GC: 5G Core Network) 20, and an ambient IoT device 300. Hereinafter, the 5GC 20 may be simply referred to as the core network (CN) 20. Note that a node other than the UE 100 may exist between the gNB 200 and the ambient IoT device 300. Such a node may be referred to as an assisting node or an intermediate node. Details of the assisting node and the intermediate node will be described later.

[0017] The UE 100 is a mobile wireless communication device. The UE 100 may be any device that is used by a user. The UE 100 may be, for example, a mobile phone terminal (including a smartphone) and / or a tablet terminal, a notebook PC, a communication module (including a communication card or a chipset), a sensor or a device provided in a sensor, a vehicle or a device provided in a vehicle (Vehicle UE), or an aircraft or a device provided in an aircraft (Aerial UE).

[0018] The NG-RAN 10 includes a base station (called a "gNB" in a 5G system) 200. The gNBs 200 are connected to each other via an Xn interface, which is an interface between base stations. The gNB 200 manages one or more cells. The gNB 200 performs wireless communication with a UE 100 that has established a connection with its own cell. The gNB 200 has a radio resource management (RRM) function, a routing function for user data (hereinafter simply referred to as "data"), a measurement control function for mobility control and scheduling, and the like. Note that the term "cell" is used to indicate the smallest unit of a wireless communication area. The term "cell" is also used to indicate a function or resource for wireless communication with the UE 100. One cell belongs to one carrier frequency (hereinafter simply referred to as "frequency").

[0019] In addition, gNBs can also be connected to the Evolved Packet Core (EPC), which is the core network of LTE. LTE base stations can also be connected to 5GC. LTE base stations and gNBs can also be connected via an inter-base station interface.

[0020] The 5GC20 includes an AMF (Access and Mobility Management Function) 30 and a UPF (User Plane Function). The AMF 30 performs various mobility controls for the UE 100. The AMF 30 manages the mobility of the UE 100 by communicating with the UE 100 using NAS (Non-Access Stratum) signaling. The UPF controls data forwarding. The AMF 30 and the UPF are connected to the gNB 200 via an NG interface, which is an interface between a base station and a core network. The devices (or nodes) included in the 5GC20 may be referred to as core network devices (or core network nodes). The AMF 30 and the UPF are examples of core network devices.

[0021] The ambient IoT device 300 is a wireless communication device capable of wireless communication with the UE 100 and / or the gNB 200. The ambient IoT device 300 may also perform wireless communication with an assist node or an intermediate node, as described below.

[0022] First, the ambient IoT device 300 can transmit information within the ambient IoT device 300 by reflecting radio waves transmitted from the UE 100 or the gNB 200 and modulating the reflected waves. Generally, the technology of reflecting unmodulated radio waves and modulating the reflected waves to transmit information is called backscattering communication. The ambient IoT device 300 has a backscattering communication function. The ambient IoT device 300 may be an information medium capable of reading information from an internal memory using the backscattering communication function. The ambient IoT device 300 may be an information medium capable of writing information to an internal memory. In this case, the ambient IoT device 300 can receive transmitted radio waves modulated with information and extract the information by demodulating the received radio waves.

[0023] Second, the ambient IoT device 300 may be a battery-less IoT device. In this case, the ambient IoT device 300 converts received radio waves into energy (specifically, power) and operates using the energy. The ambient IoT device 300 may use an energy source other than radio waves, such as light, heat, magnetism, vibration, or sound, to convert energy. Generally, such energy conversion is called energy harvesting. A known method for energy harvesting may be used. In this manner, the ambient IoT device may have an energy harvesting function. Alternatively, the ambient IoT device 300 may have a limited battery function. As described above, a "limited battery" refers to a battery that does not require manual replacement or manual charging. The ambient IoT device 300 may have a battery function that charges power obtained by the energy harvesting function. The ambient IoT device 300 may be a wireless tag.

[0024] (Example of UE configuration) Figure 2 is a diagram showing an example of the configuration of the UE 100 (user equipment) according to the first embodiment. The UE 100 includes a receiving unit 110, a transmitting unit 120, and a control unit 130. The receiving unit 110 and the transmitting unit 120 constitute a wireless communication unit that performs wireless communication with the gNB 200. The receiving unit 110 and the transmitting unit 120 are capable of wireless communication with the ambient IoT device 300.

[0025] The receiving unit 110 performs various types of reception under the control of the control unit 130. The receiving unit 110 includes an antenna and a receiver. The receiver converts a radio signal received by the antenna into a baseband signal (received signal) and outputs it to the control unit 130. The receiving unit 110 may receive a reflected wave reflected by the ambient IoT device 300 under the control of the control unit 130. The receiving unit 110 receives the received reflected wave as a radio signal, converts it into a baseband signal, and outputs it to the control unit 130.

[0026] The transmitting unit 120 performs various transmissions under the control of the control unit 130. The transmitting unit 120 includes an antenna and a transmitter. The transmitter converts a baseband signal (transmission signal) output by the control unit 130 into a radio signal and transmits it from the antenna. Alternatively, the transmitting unit 120 (or the transmitter) may transmit an unmodulated carrier wave under the control of the control unit 130. The carrier wave is reflected by the ambient IoT device 300.

[0027] The control unit 130 performs various controls and processes in the UE 100. Such processes include processes of each layer described below. The control unit 130 includes at least one processor and at least one memory. The memory stores programs executed by the processor and information used in the processes by the processor. The processor may include a baseband processor and a CPU (Central Processing Unit). The baseband processor performs modulation / demodulation, encoding / decoding, etc. of baseband signals. The CPU executes programs stored in the memory to perform various processes. In the example shown below, the operation or processing in the UE 100 may be performed by the control unit 130.

[0028] (Example of gNB configuration) Figure 3 is a diagram showing an example of the configuration of a gNB200 (base station) according to the first embodiment. The gNB200 comprises a transmitting unit 210, a receiving unit 220, a control unit 230, and a backhaul communication unit 240. The transmitting unit 210 and the receiving unit 220 constitute a wireless communication unit that performs wireless communication with the UE100. The transmitting unit 210 and the receiving unit 220 are capable of wireless communication with the ambient IoT device 300. The backhaul communication unit 240 constitutes a network communication unit that communicates with the CN20.

[0029] The transmitting unit 210 performs various transmissions under the control of the control unit 230. The transmitting unit 210 includes an antenna and a transmitter. The transmitter converts a baseband signal (transmission signal) output by the control unit 230 into a radio signal and transmits it from the antenna. Alternatively, the transmitting unit 210 (or the transmitter) may transmit an unmodulated carrier wave under the control of the control unit 230. The carrier wave is reflected by the ambient IoT device 300.

[0030] The receiving unit 220 performs various types of reception under the control of the control unit 230. The receiving unit 220 includes an antenna and a receiver. The receiver converts a radio signal received by the antenna into a baseband signal (received signal) and outputs the signal to the control unit 230. The receiving unit 220 may receive a reflected wave reflected by the ambient IoT device 300 under the control of the control unit 230. The receiving unit 220 receives the reflected wave as a radio signal, converts the received signal into a baseband signal, and outputs the baseband signal to the control unit 230.

[0031] The control unit 230 performs various controls and processes in the gNB 200. Such processes include processes for each layer described below. The control unit 230 includes at least one processor and at least one memory. The memory stores programs executed by the processor and information used in the processing by the processor. The processor may include a baseband processor and a CPU. The baseband processor performs modulation / demodulation, encoding / decoding, etc. of baseband signals. The CPU executes programs stored in the memory to perform various processes. In the example shown below, the operation or processing in the gNB 200 may be performed by the control unit 230.

[0032] The backhaul communication unit 240 is connected to adjacent base stations via an Xn interface, which is an interface between base stations. The backhaul communication unit 240 is connected to the AMF 30 / UPF via an NG interface, which is an interface between a base station and a core network. The gNB 200 is composed of a CU (Central Unit) and a DU (Distributed Unit) (i.e., functionally divided), and the two units may be connected by an F1 interface, which is a fronthaul interface.

[0033] 4 is a diagram illustrating an example of the configuration of the ambient IoT device 300 according to the first embodiment. The ambient IoT device 300 according to the first embodiment includes an antenna 310, a modulator 320, a control unit 330, and a memory 340.

[0034] The antenna 310 receives an unmodulated carrier wave. Hereinafter, this unmodulated carrier wave will be referred to as a CW (Continuous Wave). The antenna 310 converts the received CW into a received signal and outputs this received signal to the modulator 320. The antenna 310 also reflects the CW in accordance with the transmission signal output from the modulator 320 and transmits a reflected wave. Hereinafter, this reflected wave will be referred to as a BS (Back Scattering or Back Scatter). The antenna 310 performs BS transmission.

[0035] The modulator 320 may generate a transmission signal by modulating data read from the memory 340 under the control of the control unit 330. The modulator 320 outputs the modulated signal to the antenna 310. The modulator 320 may also acquire data by demodulating a signal received from the antenna 310 under the control of the control unit 330. The modulator 320 outputs the acquired data to the control unit 330. In the ambient IoT device 300, the modulator 320 may specifically be a switch. When the switch receives a reception signal from the antenna 310, the switch turns on and outputs the reception signal to the control unit 330. The switch is controlled to be on or off under the control of the control unit 330, and outputs a transmission signal corresponding to the on or off state to the antenna 310. The switch may be an RF (Radio Frequency) switch. The switch may be configured with a transistor. Alternatively, the switch may be a mechanical switch that can be physically switched on or off.

[0036] The control unit 330 has an energy harvesting function that converts the received signal received from the modulator 320 into power. The control unit 330 controls the modulator 320 and the memory 340 using the converted power as driving power for the ambient IoT device 300. The control unit 330 also reads information stored in the memory 340 and controls the modulator 320 to transmit a transmission signal corresponding to the information. For example, the control unit 330 controls the on / off of the modulator 320 to control the reflectivity of the reflected wave (BS) (e.g., whether the reflectivity is 100% or 0%) and output a transmission signal corresponding to information (e.g., 1 bit) stored in the memory 340 from the modulator 320 to the antenna 310. For example, the control unit 330 controls the timing of turning the modulator 320 on or off to output a transmission signal corresponding to multiple bits from the modulator 320 to the antenna 310. In this way, the control unit 330 controls the reflectivity of the reflected wave (BS) by controlling the on / off of the modulator 320, and is able to transmit a modulated reflected wave corresponding to the information stored in the memory 340 from the antenna 310.

[0037] The memory 340 stores various types of information. The information stored in the memory 340 may be information acquired when the ambient IoT device 300 functions as a sensor. Alternatively, the information stored in the memory 340 may be information specific to the ambient IoT device 300 that has been stored in advance in the memory 340. Examples of the specific information include identification information for the ambient IoT device 300 (or the group to which the ambient IoT device 300 belongs). The memory 340 can read the stored information under the control of the control unit 330. Information may be written to the memory 340 under the control of the control unit 330. In this case, the control unit 330 (or the modulator 320) converts the signal received from the antenna 310 into a baseband signal in the baseband band, reads information from the baseband signal, and writes the read information to the memory 340.

[0038] The ambient IoT device 300 may have a limited battery. As described above, limited battery means a battery that does not need to be manually replaced or manually charged. Furthermore, the ambient IoT device 300 may have the energy harvesting function described above.

[0039] (Protocol Stack) Next, a configuration example of a protocol stack will be described. Here, a configuration example of a protocol stack in the UE 100, the gNB 200, and the AMF 30 will be described.

[0040] FIG. 5 is a diagram illustrating an example of the configuration of a protocol stack of a radio interface of a user plane that handles data.

[0041] The user plane radio interface protocol includes a physical (PHY) layer, a medium access control (MAC) layer, a radio link control (RLC) layer, a packet data convergence protocol (PDCP) layer, and a service data adaptation protocol (SDAP) layer.

[0042] The PHY layer performs encoding / decoding, modulation / demodulation, antenna mapping / demapping, and resource mapping / demapping. Data and control information are transmitted between the PHY layer of UE100 and the PHY layer of gNB200 via a physical channel. The PHY layer of UE100 receives downlink control information (DCI) transmitted from gNB200 on a physical downlink control channel (PDCCH). Specifically, UE100 performs blind decoding of the PDCCH using a radio network temporary identifier (RNTI) and acquires successfully decoded DCI as DCI addressed to the UE. The DCI transmitted from gNB200 has a CRC (Cyclic Redundancy Code) parity bit scrambled by the RNTI added.

[0043] The MAC layer performs data priority control, retransmission processing using Hybrid Automatic Repeat reQuest (HARQ), random access procedures, etc. Data and control information are transmitted between the MAC layer of the UE 100 and the MAC layer of the gNB 200 via a transport channel. The MAC layer of the gNB 200 includes a scheduler. The scheduler determines the uplink and downlink transport format (transport block size, modulation and coding scheme (MCS)) and the resource blocks to be allocated to the UE 100.

[0044] The RLC layer transmits data to the receiving RLC layer using the functions of the MAC layer and PHY layer. Data and control information are transmitted between the RLC layer of the UE 100 and the RLC layer of the gNB 200 via a logical channel.

[0045] The PDCP layer performs header compression / decompression, encryption / decryption, and the like.

[0046] The SDAP layer maps IP flows, which are units for Quality of Service (QoS) control by the core network, to radio bearers, which are units for QoS control by the Access Stratum (AS). Note that if the RAN is connected to the EPC, SDAP may not be required.

[0047] FIG. 6 is a diagram showing an example of the configuration of a protocol stack of a radio interface of a control plane that handles signaling (control signals).

[0048] The protocol stack of the radio interface of the control plane has a Radio Resource Control (RRC) layer and a Non-Access Stratum (NAS) instead of the SDAP layer shown in FIG.

[0049] RRC signaling for various settings is transmitted between the RRC layer of UE100 and the RRC layer of gNB200. The RRC layer controls logical channels, transport channels, and physical channels according to the establishment, re-establishment, and release of radio bearers. When there is a connection (RRC connection) between the RRC of UE100 and the RRC of gNB200, UE100 is in an RRC connected state. When there is no connection (RRC connection) between the RRC of UE100 and the RRC of gNB200, UE100 is in an RRC idle state. When the connection between the RRC of UE100 and the RRC of gNB200 is suspended, UE100 is in an RRC inactive state.

[0050] The NAS, which is located above the RRC layer, performs session management, mobility management, etc. NAS signaling is transmitted between the NAS of the UE 100 and the NAS of the AMF 30. Note that the UE 100 has an application layer and the like in addition to the radio interface protocol. The layer below the NAS is called an Access Stratum (AS).

[0051] (Communication Example of Ambient IoT Device) Next, a communication example of the ambient IoT device 300 according to the first embodiment will be described.

[0052] FIG. 7 is a diagram illustrating an example of communication of the ambient IoT device 300 according to the first embodiment.

[0053] As shown in FIG. 7 , a node (or device) capable of directly communicating with the ambient IoT device 300 is referred to as a communication node 400. The communication node 400 may be the UE 100. The communication node 400 may be the gNB 200. Alternatively, the communication node 400 may be a relay device. Alternatively, the communication node 400 may be referred to as an assist node. Alternatively, the communication node 400 may be referred to as an intermediate node. Assist nodes and intermediate nodes will be described later. Alternatively, the communication node 400 may be an IAB (Integrated Access and Backhaul) node. The IAB node is, for example, a relay node interposed between the UE 100 and the gNB 200, and is a node in which a backhaul link (a communication link between the IAB node and the gNB 200) is mainly connected by wire. Alternatively, the communication node 400 may be an NCR (Network-Controlled Repeater). The NCR is, for example, a relay node interposed between the UE 100 and the gNB 200, and is a node connected mainly by wireless connection between the gNB 200 and the NCR. Alternatively, the communication node 400 may be an eNB, which is an LTE base station. The communication node 400 may be a network node that functions as a base station in 6G or later. The communication node 400 may be called a reader.

[0054] The communication node 400 transmits an unmodulated carrier wave (CW). That is, the communication node 400 performs CW transmission. The ambient IoT device 300 reflects the unmodulated carrier wave and transmits a reflected wave. The reflected wave is modulated according to the data transmitted from the ambient IoT device 300. That is, the ambient IoT device 300 performs BS transmission. The communication node 400 performs BS reception.

[0055] In addition, the communication node 400 may be a communication node that performs CW transmission and a communication node that performs BS reception.

[0056] As described above, various connection configurations between the ambient IoT devices 300 and the communication nodes 400 are assumed depending on the type of the communication node 400. Alternatively, various connection configurations of the ambient IoT devices 300 within the wireless communication system 1 are assumed. In 3GPP, such connection configurations are referred to as topologies, and four topologies are discussed. The four topologies (Topology 1, Topology 2, Topology 3, and Topology 4) will be described below.

[0057] (Topology of Ambient IoT Device 300)

[0058] (A1) Topology 1 FIG. 8A is a diagram illustrating an example of the configuration of topology 1 according to the first embodiment.

[0059] 8A, in topology 1, the ambient IoT device 300 communicates directly and bidirectionally with a base station (BS) 410. Data related to the ambient IoT device 300 and / or signaling related to the ambient IoT device 300 are transferred between the ambient IoT device 300 and the base station 410. In topology 1, the base station 410 that performs CW transmission to the ambient IoT device 300 may be different from the base station 410 that performs BS reception from the ambient IoT device 300. Topology 1 illustrates an example in which the communication node 400 is the base station 410.

[0060] (A2) Topology 2 FIG. 8B is a diagram illustrating an example of the configuration of topology 2 according to the first embodiment.

[0061] As shown in FIG. 8(B), in topology 2, an intermediate node 420 exists between the ambient IoT device 300 and the base station 410. That is, in topology 2, the ambient IoT device 300 communicates bidirectionally with the intermediate node 420. The intermediate node 420 may be a communication node 400. That is, the intermediate node 420 may be any of the gNB 200, the UE 100, a relay node, an IAB node, and an NCR. The intermediate node 420 transfers data related to the ambient IoT device 300 and / or signaling related to the ambient IoT device 300 between the base station 410 and the ambient IoT device 300. Topology 2 illustrates an example in which the communication node 400 serves as the intermediate node 420.

[0062] (A3) Topology 3 Figures 9(A) and 9(B) are diagrams showing an example configuration of topology 3 according to the first embodiment. In topology 3, communication is performed via a node called an assisting node 430. That is, as shown in Figure 9(A), the ambient IoT device 300 transmits data and / or signaling to a base station 410 and receives data and / or signaling from the assisting node 430. In Figure 9(A), the assisting node 430 may perform CW transmission, and the base station 410 may perform BS reception. Figure 9(A) shows communication in the downstream direction.

[0063] 9(B), the ambient IoT device 300 receives data and / or signaling from the base station 410 and transmits the data and / or signaling to the assist node 430. In FIG. 9(B), the base station 410 may perform CW transmission, and the assist node 430 may perform BS reception. FIG. 9(B) shows communication in the uplink stream direction.

[0064] Thus, in topology 3, the assist node 430 may be a node that performs CW transmission but does not perform BS reception (FIG. 9(A)). The assist node 430 may be a node that does not perform CW transmission but performs BS reception (FIG. 9(B)). In other words, the assist node 430 may be a node that performs either CW transmission or BS reception. Topology 3 shows an example in which the assist node 430 is the communication node 400. The assist node 430 may be any of the gNB 200, UE 100, relay node, IAB node, and NCR.

[0065] (A4) Topology 4 Fig. 10 is a diagram illustrating a configuration example of topology 4 according to the first embodiment. In topology 4, the ambient IoT device 300 communicates bidirectionally with the UE 100. Data and / or signaling is transferred between the UE 100 and the ambient IoT device 300. Topology 4 illustrates an example in which the communication node 400 is the UE 100.

[0066] (Ambient IoT Device Types) In 3GPP, it has been agreed that there are the following three types of ambient IoT devices 300.

[0067] (B1) Device 1

[0068] (B2) Device 2a

[0069] (B3) Device 2b "Device 1" is, for example, a device with peak power consumption of "1 μW" or less, no amplification in either the DL or UL direction, and backscattering transmission using an externally provided carrier. "Device 2a" is, for example, a device with peak power consumption of "several hundred μW" or less, amplification in the DL and / or UL direction, and backscattering transmission using an externally provided carrier. "Device 2b" is, for example, a device with peak power consumption of "several hundred μW" or less, amplification in the DL and / or UL direction, and UL transmission generated internally. Note that both device types have an energy storage function.

[0070] In 3GPP, any of the above terms (B1) to (B3) is used to represent the type of the ambient IoT device 300. In the present embodiment, any of the above terms (B1) to (B3) may also be used to represent the type of the ambient IoT device 300.

[0071] (Example of Block Configuration of Each Device) The 3GPP also agreed on the block configuration of "Device 1" and "Device 2a." The configuration of each block will be described.

[0072] (C1) Example of Block Configuration of "Device 1" Fig. 11 is a diagram showing an example of the block configuration of "Device 1" (i.e., the ambient IoT device 300 whose type is "Device 1") according to the first embodiment. The same blocks as those in the example configuration of Fig. 4 described above are assigned the same reference numerals.

[0073] As shown in FIG. 11 , “device 1” includes at least an antenna 310, a matching network 350, an RF energy harvester 351, a PMU (Power Management Unit) 352, an energy storage unit 353, an RF BPF (Radio Frequency Band Pass Filter) 354, an RF envelope detector (or envelope detector) 355, a BB LPF (Base Band Low Pass Filter) 356, a comparator 357, baseband logic 358, a memory 359, a backscattering modulator 360, and a clock generator 361.

[0074] The matching network 350 matches the impedance between the antenna 310 and other blocks (including the RF energy harvester 351 and the RF BPF 354) and outputs the radio signal received by the antenna 310 to the other blocks.

[0075] The RF energy harvester 351 has an energy harvesting function and extracts energy from the radio signal. The RF energy harvester 351 may also have a rectifier that converts the radio signal from an AC component to a DC component.

[0076] The PMU 352 manages (or controls) the accumulation of energy from the RF energy harvester 351 and manages (or controls) the supply of power to the blocks that require it.

[0077] The energy storage unit 353 stores energy from the RF energy harvester 351 .

[0078] The RF BPF 354 outputs a radio signal in a specific frequency band. The RF BPF 354 is used to improve selectivity. Note that the RF BPF 354 may not be included in the "device 1" depending on the implementation.

[0079] The RF envelope detector 355 converts the radio signal in the radio band output from the RF BPF 354 into a baseband signal in the baseband band.

[0080] The BB LPF 356 removes high frequency components from the baseband signal output from the RF envelope detector 355 and improves the quality of the signal input to the comparator 357 .

[0081] The comparator 357 determines whether the input signal output from the BB LPF 356 is “high” or “low.”

[0082] The baseband logic 358 includes functional blocks such as an encoder, a decoder, and a controller.

[0083] The memory 359 stores device identification information (or device ID) and the like for identifying (or distinguishing) the ambient IoT device 300 from other ambient IoT devices. The memory 359 may be a non-volatile memory (e.g., an EEPROM (Electrically Erasable Programmable Read-Only Memory)) that permanently stores the device ID and the like. The memory 359 may also be a memory (register) that temporarily stores information required only while the energy stored in the energy storage unit 353 is available.

[0084] The backscattering modulator 360 switches impedance to modulate the output signal from the baseband logic 358 into a backscattering signal. Alternatively, the backscattering modulator 360 switches impedance (the impedance of the antenna or the transmission line) using the output signal (digital signal or digital data) from the baseband logic 358 to modulate the high-frequency signal (e.g., CW) input from the antenna 310 into a backscattering signal. For example, the backscattering modulator 360 can modulate and then reflect the high-frequency signal input from the antenna 310 by terminating (not reflecting) the high-frequency input signal for digital data "0" and opening (reflecting) the high-frequency input signal for digital data "1."

[0085] The clock generator 361 generates the clock signals required within the device.

[0086] The above is an example of the configuration of "device 1." In relation to the example of the configuration of the ambient IoT device 300 shown in FIG. 4 , for example, the following applies. That is, the matching network 350, the RF BPF 354, the RF envelope detector 355, the BB LPF 356, the comparator 357, and the backscattering modulator 360 may be included in the modulator 320 shown in FIG. 4 . Also, the PMU 352 and the baseband logic 358 may be included in the control unit 330 shown in FIG. 4 . Furthermore, the memory 359 may correspond to the memory 340 shown in FIG. 4 .

[0087] (C2) Example of block configuration of "device 2a" Fig. 12 is a diagram showing an example of the block configuration of "device 2a" (i.e., the ambient IoT device 300 whose type is "device 2a") according to the first embodiment. The same reference numerals are used to designate the same blocks as those in the example configurations of Figs. 4 and 11 described above.

[0088] The "device 2a" shown in FIG. 12 further includes at least an LNA (Low Noise Amplifier) ​​365, a baseband amplifier 366, a large frequency shifter 367, a reflection amplifier 368, and an energy harvester 369 in addition to the "device 1" shown in FIG. 11.

[0089] LNA365 amplifies the output signal from RF BPF354 (i.e., the signal from the reader (gNB200 or UE100)) to improve the signal strength and signal sensitivity at the receiving side.

[0090] The baseband amplifier 366 amplifies the baseband signal output from the RF envelope detector 355 to improve the signal strength.

[0091] The large frequency shifter 367 shifts the frequency of the backscattering signal from one frequency (eg, the FDD-DL frequency) to another frequency (eg, the FDD-UL frequency).

[0092] The energy harvester 369 generates energy from an environment using a source other than an RF signal. Specifically, energy harvesting sources include sunlight (solar panels), vibration (vibration power generation), and heat (thermal power generation), but are not limited to these.

[0093] The above describes an example configuration of the "device 2a." Of the blocks shown in Fig. 12, the LNA 365 and the large frequency shifter 367 are items for future study. In the example block configuration shown in Fig. 12, in relation to the example block configuration shown in Fig. 4, the LNA 365, the baseband amplifier 366, the large frequency shifter 367, and the reflection amplifier 368 may be further included in the modulator 320.

[0094] (PRDCH and PDRCH) In addition, the 3GPP has also agreed on the physical channels used by the ambient IoT device 300.

[0095] For example, as shown in FIG. 7, the physical channel used for transmission from the communication node 400 to the ambient IoT device 300 (hereinafter, sometimes referred to as "R2D (Reader to Device) transmission") is called the PRDCH (Physical Reader to Device channel).

[0096] On the other hand, the physical channel used for transmission from the ambient IoT device 300 to the communication node 400 (hereinafter, sometimes referred to as "D2R (Device to Reader) transmission") is called a PDRCH (Physical Device to Reader channel).

[0097] For example, in topology 1 shown in Figure 8 (A), the physical channel used for R2D transmission from BS410 (or gNB200) to ambient IoT device 300 is PRDCH, and the physical channel used for D2R transmission from ambient IoT device 300 to BS410 is PDRCH.

[0098] In topology 2 shown in FIG. 8(B), the physical channel used for R2D transmission from the intermediate node 420 to the ambient IoT device 300 is PRDCH, and the physical channel used for D2R transmission from the ambient IoT device 300 to the intermediate node 420 is PDRCH.

[0099] In the following, a communication link using a PRDCH may be referred to as an R2D link, and a communication link using a PDRCH may be referred to as a D2R link. In the following, the PRDCH and the R2D link may be used without distinction. In the following, the PDRCH and the D2R link may be used without distinction.

[0100] (Communication control method according to the first embodiment) Generally, the MAC entity of the gNB 200 includes a scheduler. The scheduler allocates radio resources (time resources and / or frequency resources) (hereinafter, sometimes referred to as "resources") to the UE 100. In particular, with regard to the uplink direction, the scheduler may dynamically allocate resources to the UE 100 using DCI (Downlink Control Information), or may allocate resources using an RRC message (called configured scheduling). The UE 100 can use the allocated radio resources to transmit data to the gNB 200, etc. In this way, the gNB 200 schedules resources and allocates them to the UE 100, thereby enabling efficient use of resources.

[0101] Meanwhile, 3GPP currently does not specify how radio resources are allocated to the ambient IoT device 300. Therefore, it is expected that multiple ambient IoT devices 300 will independently use radio resources to perform D2R transmission. In this case, the D2R transmissions may collide, making it impossible to properly communicate between the ambient IoT device 300 and the communication node 400.

[0102] Therefore, the first embodiment aims to suppress collisions of D2R transmissions and to enable the ambient IoT device 300 to appropriately communicate with the communication node 400 by using scheduled resources.

[0103] Therefore, in the first embodiment, the communication node 400 notifies the ambient IoT device 300 of resource information related to D2R transmission. Specifically, the communication node (e.g., the communication node 400) transmits a transmission signal (e.g., an R2D signal) composed of a modulated wave obtained by modulating a command and an unmodulated continuous wave (e.g., CW) to the IoT device (e.g., the ambient IoT device 300). Here, the command includes resource information related to resources used for transmission from the IoT device to the communication node.

[0104] In this way, the ambient IoT device 300 is notified of the resource information, and is therefore able to perform D2R transmission using the resource information. For example, by allocating resource information to each ambient IoT device 300, it is possible to suppress collisions in D2R transmission. Furthermore, by suppressing such collisions, the ambient IoT device 300 is able to perform appropriate communication with the communication node 400 using the scheduled resources.

[0105] (Operation Examples According to First Embodiment) In the first embodiment, the following three operation examples will be described.

[0106] (D1) First Operation Example: Example in which Device ID and Predetermined Rule are Used

[0107] (D2) Second operation example: Example in which resources are specified each time

[0108] (D3) Third Operation Example: Example in which Resources are Pre-configured

[0109] (D1) First Operation Example First, a first operation example according to the first embodiment will be described. In the first operation example, resources are determined based on a device ID and a predetermined rule.

[0110] Fig. 13 is a diagram showing a first operation example. In Fig. 13, a communication node 400 is described, but the communication node 400 may be a reader as described above.

[0111] As shown in Figure 13, the transmitting unit of the communication node 400 (the transmitting unit 120 of the UE 100 or the transmitting unit 210 of the gNB 200) transmits a transmission signal (R2D signal) consisting of a modulated wave modulated with a command and an unmodulated continuous wave (CW).

[0112] The command includes resource information regarding the resources to be used for the D2R transmission.

[0113] First, the resource information may include reference timing information indicating that the timing of receiving the command is the reference timing. Alternatively, even if the resource information does not include the reference timing information, if the command includes the resource information, the ambient IoT device 300 may implicitly regard the timing of receiving the command as the reference timing.

[0114] Second, the resource information may include identification information. The identification information may be a device ID of the ambient IoT device 300. The identification information may be a group ID of a group to which the ambient IoT device 300 belongs (a group consisting of multiple ambient IoT devices 300).

[0115] Third, the resource information may include distribution information indicating information for distributing the transmission timing and / or transmission frequency of the D2R transmission for each ambient IoT device 300. Specific examples of the distribution information will be described below, and three cases will be described here: (D1-1) a case where the transmission timing is distributed for each ambient IoT device 300, (D1-2) a case where the transmission frequency is distributed for each ambient IoT device 300, and (D1-3) a case where the transmission timing and transmission frequency are distributed for each ambient IoT device 300.

[0116] (D1-1) When distributing transmission timing When distributing transmission timing for each ambient IoT device 300, the distribution information includes a "slot number upper limit value (or slot number upper limit value)" and a "slot measurement timer value."

[0117] The ambient IoT device 300 has a slot measurement timer and a slot measurement counter. The slot measurement timer starts to run at a reference timing, and the slot measurement counter is set to "0" (or "1") at the reference timing.

[0118] Furthermore, there are time slots separated by a predetermined time interval (for example, the time measured by a slot measurement timer), and the slot measurement timer sequentially measures (or counts) the number of slots (or slot numbers) of the time slot from the reference timing. When the number of slots measured by the slot measurement timer reaches the "slot measurement timer value" notified as the distribution information, the slot measurement counter is incremented by one, and the slot measurement timer is restarted (reset) to start measuring again. By repeating the above, when the count value of the slot measurement counter reaches the "slot number upper limit value" notified as the distribution information, the transmission timing assigned to the ambient IoT device 300 is completed, and the slot measurement timer is not restarted. In such a situation where the slot measurement timer and slot measurement counter are operating, the control unit 330 of the ambient IoT device 300 determines that it is the D2R transmission permission timing (or transmission permission slot) if the "current slot number (or slot number)" measured by the slot measurement timer is a "transmission permission slot" that satisfies the following formula (1).

[0119] [Device ID] mod [Upper limit of number of slots] = [Permitted transmission slot] (1) The transmitter (modulator 320 and antenna 310) of the ambient IoT device 300 performs D2R transmission at a timing that satisfies equation (1).

[0120] As shown in equation (1), since the device ID is used, it is possible to distribute the "transmission permission slot." Therefore, the transmission timing of the D2R transmission may be different for each ambient IoT device 300. In this way, the transmission resource (transmission permission slot) can be identified based on the device ID. Note that identifying the transmission permission slot using equation (1) is also an example of a predetermined rule.

[0121] (D1-2) When Distributing Transmission Frequencies When distributing transmission timing for each ambient IoT device 300, the distribution information includes an "upper limit value for the number of channels (or upper limit value for the number of channel numbers)" and a "channel spacing." The distribution information may further include an "offset."

[0122] There are channels (or frequency bands) used for D2R transmission. Channel numbers are assigned within these channels. The "upper limit of channel number" represents the upper limit of the channel numbers (or number of channels) included within the channels used for D2R transmission. For example, if the "upper limit of channel number" is "10", then within the channels used for D2R transmission, there will be channels numbered #1 to #10. The intervals between channel numbers are constant. For example, the interval between channel number #1 and channel number #2, the interval between channel number #2 and channel number #3, etc. are all the same. The "channel interval" represents such an interval between channels.

[0123] The control unit 330 of the ambient IoT device 300 determines that the [permitted transmission channel number] that satisfies the following formula (2) is the channel number of the channel that is permitted for transmission.

[0124] [Device ID] mod [Upper limit of number of channels] = [Allowed transmission channel number] (2) If the distribution information includes an offset, the control unit 330 determines that the value obtained by adding the offset to the channel number that satisfies formula (2) is the channel number of the allowed transmission channel. For example, if D2R transmission is performed by random access in an offset channel, the offset makes it possible to separate the channel for random access from the channel for scheduling.

[0125] The permitted transmission frequency itself can be calculated by multiplying the "channel spacing" by the "permitted transmission channel number." The transmitter of the ambient IoT device 300 performs D2R transmission using the frequency. At this time, the control unit 330 may operate the modulator 320 at the frequency by adjusting the on / off speed (cycle) of the modulator 320 to match the frequency.

[0126] As shown in equation (2), the permitted transmission channel is identified using the device ID, so that it is basically possible to determine the permitted transmission channel for each ambient IoT device 300. The permitted transmission channel (transmission frequency) can be identified using the device ID. Identifying the permitted transmission channel using equation (2) is also an example of a predetermined rule.

[0127] (D1-3) When Distributing Transmission Timing and Transmission Frequency When distributing transmission timing and transmission frequency, operation is performed by combining the above (E1) and (E2). The distribution information includes a "slot count upper limit," a "slot measurement timer value," a "channel count upper limit," and a "channel interval." The control unit 330 of the ambient IoT device 300 determines the transmission permission slot using equation (1). At this time, the control unit 330 determines the quotient (the part of the division solution) of [device ID] divided by [slot count upper limit] as the [new device ID]. Then, the control unit 330 identifies the transmission permission channel using the following equation (3), which replaces [device ID] with [new device ID] in equation (2).

[0128] [New device ID] mod [Upper limit of number of channels] = [Permitted transmission channel] (3) Fig. 14 shows an example of the [Permitted transmission slot] and [Permitted transmission channel] calculated as above. Fig. 14 shows an example of the calculation when [Upper limit of number of slots] = "2" and [Upper limit of number of channels] = "2".

[0129] In this way, after the transmission permission slot is specified using equation (1), the transmission permission channel is specified using equation (3) using the new device ID. Therefore, even if there are multiple ambient IoT devices 300 with the same transmission permission slot (for example, "device ID #1" and "device ID #3" in FIG. 14 have the same transmission permission slot), it is possible to distribute the transmission permission channels ("device ID #1" and "device ID #3" in FIG. 14 have different transmission permission channels). Therefore, it is possible to perform D2R transmission at different transmission timings and using different transmission frequencies for each ambient IoT device 300.

[0130] In the above example, the transmission permission slot is identified using formula (1) and then the transmission channel is identified using formula (3). However, the transmission permission channel may be identified first, and then the transmission permission slot may be identified. In this case, the control unit 330 of the ambient IoT device 300 identifies the transmission permission channel using formula (2), sets the quotient of [device ID] / [upper limit value of number of channels] as [new device ID], and identifies the transmission permission slot using the following formula (4) instead of formula (1).

[0131] [New device ID] mod [Maximum number of slots] = [Allowed transmission slot] ... (4) In this case too, by using the new device ID, even if there are multiple ambient IoT devices 300 with the same allowed transmission channel, it becomes possible to distribute the allowed transmission slots, thereby making it possible to suppress collisions of D2R transmissions.

[0132] Note that examples of predetermined rules include specifying a transmission permission slot and a transmission permission channel using equations (1) and (3), and specifying a transmission permission slot and a transmission permission channel using equations (2) and (4). The receiving unit of the ambient IoT device 300 receives the transmission signal.

[0133] Returning to FIG. 13, in step S12, the control unit 330 of the ambient IoT device 300 uses the resource information extracted from the command to identify the transmission resource and transmission frequency to be used for D2R transmission in accordance with the predetermined rules described above.

[0134] In step S13, the transmitter of the ambient IoT device 300 performs D2R transmission using the identified resource.

[0135] (D2) Second Operation Example Next, a second operation example according to the first embodiment will be described. The second operation example is an example in which the communication node 400 specifies the resources to be used for D2R transmission each time. Specifically, the resource information transmitted from the communication node 400 to the ambient IoT device 300 includes either a transmission permission slot or a transmission permission channel for each device ID. In this way, in the second operation example, resource information is transmitted for each device ID, so that D2R transmission can be performed using different resources for each ambient IoT device 300, thereby making it possible to suppress collisions of D2R transmission.

[0136] FIG. 15 is a diagram illustrating a second operation example.

[0137] 15, in step S21, the transmitter of the communication node 400 transmits a transmission signal composed of a modulated wave obtained by modulating a command and a CW. The command includes resource information used for D2R transmission.

[0138] First, the resource information includes identification information. The identification information is preferably the device ID of the ambient IoT device 300. This is to prevent collisions of D2R transmissions between the ambient IoT devices 300. However, the identification information may also be the group ID of the group to which the ambient IoT device 300 belongs. This makes it possible to prevent collisions of D2R transmissions between groups.

[0139] Second, the resource information includes at least one of a transmission permission slot and a transmission permission channel. As in the first operation example, the transmission permission slot and the transmission permission channel represent a slot and a channel for which transmission is permitted, respectively. The transmission permission slot may be represented by a slot number, and the transmission permission channel may be represented by a channel number. Since the resource information includes a device ID, it is possible to allocate resource information for D2R transmission for each device ID (i.e., for each ambient IoT device 300). Note that, as in the first operation example, the slot may represent a time slot separated by a certain time.

[0140] In step S22, the control unit 330 of the ambient IoT device 300 receives the command and checks (or identifies) the resource permitted for transmission based on the resource information included in the command.

[0141] In step S23, the transmitter of the ambient IoT device 300 performs D2R transmission using the confirmed resource.

[0142] (D3) Third Operation Example Next, a third operation example according to the first embodiment will be described. The third operation example is an example in which resource information is written in advance to the memory 340 of the ambient IoT device 300. The resource information may be the resource information described in the first operation example. The resource information may be the resource information described in the second operation example. In the third operation example, if resource information written in the memory 340 of the ambient IoT device 300 is missing, the communication node 400 includes the missing resource information in a command and transmits it to the ambient IoT device 300. That is, the transmitter of the communication node 400 includes the resource information (missing resource information) not held in the memory 340 of the ambient IoT device 300 in the command and transmits it. In this way, in the third embodiment, the resource information described in the first operation example or the resource information described in the second operation example is used, and D2R transmission is performed between the ambient IoT devices 300 using different resources, thereby making it possible to suppress D2R transmission collisions. Furthermore, even if there is resource information that has not been written to the memory 340, it is transmitted from the communication node 400, so the ambient IoT device 300 can also perform D2R transmission appropriately.

[0143] FIG. 16 is a diagram illustrating a third operation example.

[0144] As shown in FIG. 16 , in step S31, the ambient IoT device 300 stores resource information in the memory 340. The resource information may be written to the memory 340 when the ambient IoT device 300 is shipped from a factory. The resource information may also be written when the ambient IoT device 300 is installed. The resource information written to the memory 340 may be the resource information described in the first operation example, i.e., the resource information (at least one of reference timing information, ID information, and dispersion information) included in the command transmitted from the communication node 400 to the ambient IoT device 300 (step S11 in FIG. 13 ). Alternatively, the resource information written to the memory 340 may be the resource information described in the second operation example, i.e., the resource information (ID information and transmission permission slot and / or transmission permission channel) included in the command transmitted from the communication node 400 to the ambient IoT device 300 (step S21 in FIG. 15 ). Alternatively, the resource information written to the memory 340 may be a part of the resource information described in the first operation example. The resource information may be part of the resource information described in the second operation example. The missing resource information is included in a command and transmitted from the communication node 400 to the ambient IoT device 300.

[0145] In step S32, the transmitting unit of the communication node 400 transmits a transmission signal composed of a modulated wave obtained by modulating the command and a CW. The command may include a device ID. Alternatively, the command may include a group ID. The command may include missing resource information. The receiving unit of the ambient IoT device 300 receives the transmission signal. The control unit 330 of the ambient IoT device 300 may regard the time point at which the command is received as a reference timing.

[0146] In step S33, the control unit 330 of the ambient IoT device 300 checks the resources permitted for transmission. If the resource information is the same as that in the first operation example, the control unit 330 may identify the resources permitted for transmission using the method described in the first operation example. If the resource information is the same as that in the second operation example, the control unit 330 may identify the resources permitted for transmission from the resource information. The control unit 330 will obtain the missing resource information from the command.

[0147] In step S34, the transmitter of the ambient IoT device 300 performs D2R transmission using the resource permitted for transmission.

[0148] In the third operation example, the communication node 400 (UE100 or gNB200) has been described as holding the missing resource information. For example, the AMF 30 may hold the missing resource information. In this case, the AMF 30 may use a NAS message or an NG-AP message to transmit the missing resource information to the UE 100 or the gNB 200, respectively. This is because it is more efficient for the AMF 30 to hold information regarding communication with the ambient IoT device 300, including the missing resource information, than for the gNB 200 or the UE 100 to hold the information.

[0149] [Other Embodiments] The above-described operational flows are not limited to being implemented independently, but can be implemented by combining two or more operational flows. For example, some steps of one operational flow may be added to another operational flow, or some steps of one operational flow may be replaced with some steps of another operational flow. In each flow, it is not necessary to execute all steps, and only some steps may be executed.

[0150] In the above-described embodiments and examples, an example in which the base station is an NR base station (gNB) has been described, but the base station may be an LTE base station (eNB) or a 6G base station. The base station may also be a relay node such as an IAB (Integrated Access and Backhaul) node. The base station may also be a DU of the IAB node. The UE 100 may also be an MT (Mobile Termination) of the IAB node.

[0151] That is, the UE 100 may be a terminal function unit (a type of communication module) for a base station to control a repeater that relays signals. Such a terminal function unit is referred to as an MT. Examples of the MT include, in addition to the IAB-MT, an NCR (Network Controlled Repeater)-MT and a RIS (Reconfigurable Intelligent Surface)-MT.

[0152] The term "network node" primarily refers to a base station, but may also refer to a core network device or a part of a base station (CU, DU, or RU). A network node may also be configured by a combination of at least a part of a core network device and at least a part of a base station.

[0153] A program may be provided that causes a computer to execute each process performed by the UE 100, the gNB 200, the communication node 400, or the core network device. The program may be recorded on a computer-readable medium. The computer-readable medium can be used to install the program on a computer. Here, the computer-readable medium on which the program is recorded may be a non-transitory recording medium. The non-transitory recording medium is not particularly limited, and may be, for example, a recording medium such as a CD-ROM and / or a DVD-ROM. Furthermore, circuits that execute each process performed by the UE 100, the gNB 200, the communication node 400, or the core network device may be integrated, and at least a portion of the UE 100, the gNB 200, the communication node 400, or the core network device may be configured as a semiconductor integrated circuit (chip set, SoC: System on a chip).

[0154] The functions performed by the UE 100, the gNB 200, the communication node 400, or the core network device may be implemented in circuitry or processing circuitry, including general-purpose processors, application-specific processors, integrated circuits, ASICs (Application Specific Integrated Circuits), a CPU (a Central Processing Unit), conventional circuits, and / or combinations thereof, programmed to perform the described functions. A processor includes transistors and other circuits and is considered to be circuitry or processing circuitry. A processor may also be a programmed processor that executes a program stored in memory. In this specification, circuitry, unit, or means refers to hardware that is programmed to perform the described functions or hardware that executes them. The hardware may be any hardware disclosed herein or any hardware known to be programmed or capable of performing the described functions. If the hardware is a processor, the circuitry, means, or unit is a combination of hardware and software used to configure the hardware and / or processor.

[0155] As used in this disclosure, the terms "based on" and "depending on / in response to" do not mean "based only on" or "depending only on," unless expressly stated otherwise. The term "based on" means both "based only on" and "based at least in part on." Similarly, the term "depending on" means both "depending only on" and "depending at least in part on." The terms "include," "comprise," and variations thereof do not mean including only the listed items, but may mean including only the listed items or may include additional items in addition to the listed items. Additionally, the term "or," as used in this disclosure, is not intended to mean an exclusive or. Furthermore, any reference to elements using designations such as "first," "second," etc., as used in this disclosure does not generally limit the quantity or order of those elements. These designations may be used herein 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 therein or that the first element must precede the second element in some way. In this disclosure, where articles are added by translation, such as a, an, and the in English, these articles shall include the plural unless the context clearly indicates otherwise.

[0156] Although one embodiment has been described in detail above with reference to the drawings, the specific configuration is not limited to the above, and various design changes can be made within the scope of the gist. Furthermore, the embodiments, operation examples, and processes can be appropriately combined within the scope of not being inconsistent.

[0157] This application claims priority to U.S. Provisional Application No. 63 / 573,611 (filed April 3, 2024), the entire contents of which are incorporated herein by reference.

[0158] (Appendix 1) The above can be summarized as follows.

[0159] (Supplementary Note 1) A communication control method in a wireless communication system, comprising: a step in which a communication node transmits, to an IoT device, a transmission signal composed of a modulated wave obtained by modulating a command and an unmodulated continuous wave, wherein the command includes resource information regarding resources used for transmission from the IoT device to the communication node.

[0160] (Supplementary Note 2) The communication control method according to Supplementary Note 1, wherein the command includes reference timing information indicating that a timing at which the command is received is used as a reference timing.

[0161] (Supplementary Note 3) The communication control method according to Supplementary Note 1 or Supplementary Note 2, wherein the command includes identification information of the IoT device.

[0162] (Supplementary Note 4) The communication control method according to any one of Supplementary Notes 1 to 3, wherein the resources are acquired based on identification information of the communication nodes.

[0163] (Supplementary Note 5) The communication control method according to any one of Supplementary Notes 1 to 4, wherein the resource information includes distribution information indicating information for distributing transmission timing and / or transmission frequency for each of the IoT devices.

[0164] (Supplementary Note 6) The communication control method according to any one of Supplementary Notes 1 to 5, wherein the shared information includes a slot number upper limit value representing the maximum number of time slot numbers assigned to the IoT device, and a slot measurement timer value representing a time slot number for resetting a slot measurement timer used in the IoT device.

[0165] (Supplementary Note 7) The communication control method according to any one of Supplementary Notes 1 to 6, wherein the distributed information includes a channel number upper limit value indicating an upper limit value of the number of channels used for transmission from the IoT device to the communication node, and channel spacing information indicating a channel spacing.

[0166] (Supplementary Note 8) The communication control method according to any one of Supplementary Note 1 to Supplementary Note 7, wherein the resource information includes, for each identification information of the IoT device, at least one of a transmission permission slot indicating a time slot in which transmission is permitted and a transmission permission channel indicating a channel in which transmission is permitted.

[0167] (Supplementary Note 9) The communication control method according to any one of Supplementary Notes 1 to 8, wherein the resource information is written in advance to a memory of the IoT device, and the transmitting step includes a step in which the communication node transmits resource information that the IoT device does not hold in the memory.

[0168] (Supplementary Note 10) A communication node in a wireless communication system, comprising: a transmitter that transmits a transmission signal composed of a modulated wave obtained by modulating a command and an unmodulated continuous wave to an IoT device, wherein the command includes resource information related to resources used for transmission from the IoT device to the communication node.

[0169] (Second Note) 1. Introduction RAN#102 approved a new research item on ambient IoT solutions. Its objectives consist of a general scope and WG-specific tasks. Specifically for RAN2, the following topics are indicated as research targets:

[0170] RAN2 initiative: Investigate and determine the functionality required for compact protocol stacks and lightweight signaling procedures for ambient IoT, and their functionality to enable Device-Originated, Device-Terminated Triggered (DO-DTT) and Device-Terminated (DT) data transmission.

[0171] Examples: Paging Random access Data transmission (including the necessary radio resource control aspects), respecting general range limitations Interaction with higher layers Functionality not listed above shall only be considered if deemed essential.

[0172] The appendix provides initial considerations for each topic identified in the Study Item Description (SID).

[0173] 2. Discussion 2.1 Ambient IoT Compact Protocol Stack According to SID, the general range of air interfaces and deployment scenarios are as follows:

[0174] A. The overall objective is to study a harmonized air interface design for Ambient IoT, minimizing differences where necessary, to enable the following devices: [...] - For Topology 1 and Topology 2 (UE as an intermediate node under network control) (no RRC state, no mobility (i.e., no functionality like cell selection / reselection at least), no HARQ, no ARQ) according to TR38.848. [...] B. Deployment scenarios with the following characteristics, referring to the table in section 4.2.2 of TR38.848: - Deployment scenario 1 using Topology 1 - Base station and coexistence characteristics: microcell, same site - Deployment scenario 2 using Topology 2, with UE under network control as intermediate node - Base station and coexistence characteristics: macrocell, same site - The intermediate node is located indoors.

[0175] In TR38.848, Topology 1 and Topology 2 are recorded as follows:

[0176] 4.2.1.1 Topology 1: BS and Ambient IoT Devices In Topology 1, Ambient IoT devices communicate directly and bidirectionally with the base station. The communication between the base station and the ambient IoT device includes ambient IoT data and / or signaling. In this topology, the BS transmitting to the ambient IoT device may be different from the BS receiving from the ambient IoT device.

[0177] 4.2.1.2 Topology 2: Intermediate Nodes Between BS and Ambient IoT Devices In Topology 2, Ambient IoT devices communicate bidirectionally with intermediate nodes between the devices and the base station. In this topology, the intermediate nodes are Ambient IoT-enabled relays, IAB nodes, UEs, repeaters, etc. The intermediate nodes forward Ambient IoT data and / or signaling between the BS and Ambient IoT.

[0178] In Topology 2, the SID is written as "UE is an intermediate node under NW control," and in FIG. 8(B), the Uu interface is used between the BS and the intermediate node. Therefore, the gNB reuses the Uu interface to control the UE acting as a user ambient IoT reader. For example, when allocating radio resources to the UE to perform ambient IoT transmission and reception. Although this is a very natural interpretation derived from the SID and TR, it is worth clearly checking in RAN2.

[0179] Note: In Topology 1, the gNB acts as a user ambient IoT reader, so it is assumed that the Uu interface is not required to control the transmission and reception of ambient IoT.

[0180] Proposal 1: For Topology 2, RAN2 needs to ensure that the Uu interface is reused so that the gNB can control the UE acting as the user ambient IoT reader.

[0181] With regard to ambient IoT communication (the link between ambient IoT readers and ambient IoT devices), there is no difference between Topology 1 and Topology 2, at least from the perspective of RAN 2. Therefore, as a baseline for both topologies, the corresponding protocol stacks should be the same. For example, as SID clearly states, a compact protocol stack should be used, so one option is to have one simple layer called "L2 / L3 layer" above the PHY layer. This is because SID is clearly limited to "no RRC state, no mobility (i.e., at least no functions like cell selection / reselection), no HARQ, no ARQ" (i.e., at least "heavy" RRC layer, RLC layer, HARQ of MAC layer are not required. However, it is thought that "compact" MAC functions (e.g., user demultiplexing and random access) and "compact" RRC functions (e.g., paging processing and communication with higher layers) will be required, and these may be integrated into the "L2 / L3" layer. It is still debatable whether security functions (i.e., PDCP layer) are required (it may be necessary up to SA3).

[0182] Proposal 2: For both Topology 1 and Topology 2, RAN2 should agree that a common protocol stack design is applied between the user ambient IoT reader and the ambient IoT device.

[0183] Proposal 3: RAN2 should discuss the functions required for the protocol stack between user ambient IoT readers and ambient IoT devices, including how many layers are required.

[0184] 2.2 Paging In the existing paging, the basic idea is that a network page initiates an RRC connection establishment / resumption procedure between the UE and the paged UE. However, it is clearly stated that there is no RRC state in the SID. Considering this limitation, paging in the ambient IoT can be considered as a kind of "polling" for the network to know whether a specific ambient IoT device is present in a specific area / cell. RAN2 should discuss what paging in the ambient IoT system looks like.

[0185] Proposal 4: RAN2 should discuss the definition of "paging" for ambient IoT devices.

[0186] Regardless of the definition (e.g., "paging" or "polling"), a "paging message" sent from a user ambient IoT reader to an ambient IoT device should include a device-specific ID similar to the UE-ID included in the paging message. RAN2 should discuss whether the ambient IoT device has a device-specific ID. If an ID can be assumed, that ID can also be used for trigger signaling of DO-DTT data transmission, as discussed in the next section.

[0187] Proposal 5: RAN2 should discuss whether ambient IoT devices have device-specific IDs.

[0188] It is desirable to clarify that, under general assumptions, Topology 1 and Topology 2 can coexist, i.e., in the same network, where an ambient IoT device belongs to a cell (i.e., Topology 1) and another ambient IoT device belongs to a UE (i.e., Topology 2), or they are always separated.

[0189] Another point that needs to be clarified is whether the network needs to know which topology / gNB / cell / UE a particular ambient IoT belongs to. If the network needs to know, it should be discussed which network node (e.g., AMF or gNB) should handle it.

[0190] These issues should be discussed in RAN2 as these clarifications will affect the design of the paging scheme.

[0191] Proposal 6: RAN2 should discuss whether the two topologies can coexist on the same network.

[0192] Proposal 7: RAN2 should discuss whether the network needs to know which topology / gNB / cell / UE a particular ambient IoT device belongs to.

[0193] 2.3 Random Access and Data Transmission The basic idea behind existing random access is that the UE transmits a preamble (Msg1) and the gNB transmits a random access response (Msg2) to determine the timing advance (TA), etc. However, in the case of ambient IoT, the SID includes a "Coverage Design Objective: Maximum distance from indoor devices is 10 to 50 m according to TR38.848: Range in which the WG can be selected" (i.e., TA is a value of 0.03 to 0.17 [us] for 10 to 50 [m]). Therefore, RAN2 should discuss whether it is really necessary to apply TA to ambient IoT communication.

[0194] Proposal 8: RAN2 should discuss whether it is really necessary to apply timing advance to the transmission of ambient IoT devices, considering that the coverage distance is less than 50 m.

[0195] TR38.848 identifies three traffic types: DO-A (Device-originated, autonomous), DO-DTT (Device-originated, Device-terminated triggered), and DT (Device-terminated). The TR does not explicitly define these traffic types, but our understanding is shown in the diagram below. RAN2 needs to confirm the definitions of the three traffic types.

[0196] Proposal 9: In RAN2, it should be confirmed that DO-A means that ambient IoT devices transmit data autonomously.

[0197] Proposal 10: In RAN2, it should be confirmed that DO-DTT means that the ambient IoT device transmits data triggered by the user ambient IoT reader.

[0198] Proposal 11: In RAN2, the DT needs to confirm that the user ambient IoT reader means to send data to the ambient IoT device.

[0199] As discussed in Proposal 4 above, when TA adjustment is not required, random access is used for DO-A data transmission instead. This may seem similar to two-stage RA, but the major difference is that there is no preamble transmission. This data transmission method is worth discussing because it can achieve extremely low power consumption.

[0200] Proposal 12: RAN2 should discuss whether DO-A transmission should be performed as random access without preamble transmission.

[0201] On the other hand, in DO-DTT, DO data transmission is triggered by the user ambient IoT reader. Similar to the current dynamic granting scheme, some rules for data transmission of ambient IoT devices can be easily created. For example, data transmission occurs four slots after receiving a trigger. Alternatively, the slot in which data transmission occurs can be dynamically indicated by the user ambient IoT reader. Either option means that DO-DTT data transmission is not based on random access.

[0202] Proposal 13: RAN2 should discuss whether DO-DTT data transmission is a kind of scheduled transmission that is not random access, for example, in some slots after receiving a trigger.

[0203] With respect to DT, the user ambient IoT reader can determine when data transmission is performed, such as the current downlink allocation.

[0204] Proposal 14: In RAN2, it should be discussed whether DT data transmission is performed at any timing determined by the user ambient IoT reader.

[0205] SID describes the following device types as having a "harmonized air interface design":

[0206] i. : Peak power consumption of 1 μW, with energy storage function, initial sampling frequency offset (SFO) is up to 10 Ｘ ppm, the device has no DL (downlink) or UL (uplink) amplification. The device's UL transmission is backscattered on an externally provided carrier.

[0207] ii. Peak power consumption is less than several hundred μW １ , with energy storage function, initial sampling frequency offset (SFO) up to 10 Ｘppm, DL and / or UL amplification possible within the device. The device's UL transmission is backscattered off a carrier that is either generated within the device or provided externally.

[0208] Therefore, backscatter transmission should be the baseline for any functionality. Considering backscatter transmission, a carrier wave (CW) from the gNB and / or UE is always required. It is assumed that the CW is used for both data transmission and data / trigger reception. Therefore, from the perspective of an ambient IoT device, it may be necessary to know which CW can be used for which purpose.

[0209] Proposal 15: RAN2 should discuss whether ambient IoT devices need to identify the purpose of CW, i.e., data transmission, data reception, or trigger reception.

[0210] 2.4 Interaction with Higher Layers Interaction with higher layers is expected to depend on many factors, such as whether data transfer is via U-plane (same as UE) or C-plane (similar to Data over NAS in NB-IoT DoNAS). Therefore, RAN2 should currently wait for the progress of other WGs, such as SA2.

[0211] Proposal 16: RAN2 should wait for progress in other WGs before starting discussions on interactions with higher layers.

[0212] 2.5 Other Potential Functions Other potential L2 / L3 functions are listed below. RAN2 should discuss whether or not there are any functions required for ambient IoT other than paging, random access, data transmission, and interaction with higher layers, as this directly impacts the design of the protocol stack.

[0213] User demultiplexing: If multiple accesses are supported, the reader may need to distinguish backscatter transmissions from a particular ambient IoT device from other backscatter transmissions from other ambient IoT devices.

[0214] Data segmentation / combining: If there is a limit on the so-called "transport block size," user ambient IoT readers and devices may need to segment / combine larger data sizes. Whether ambient IoT devices can handle such processing needs further investigation.

[0215] Security: Encryption and integrity protection may be implemented at the discretion of SA3. The processing power of surrounding IoT devices must be taken into account.

[0216] Proposal 17: RAN2 should discuss whether additional functionality is needed for L2 / L3 processing, and if so, what functionality is needed.

Claims

1. A communication control method in a wireless communication system, comprising: a communication node transmitting a transmission signal to an IoT (Internet of Things) device; and the transmission signal including a command including resource information related to resources used for transmission from the IoT device to the communication node.

2. The communication control method according to claim 1, wherein the transmission signal includes a modulated wave obtained by modulating the command.

3. The communication control method according to claim 1, wherein the transmission signal includes an unmodulated continuous wave.

4. A communication control method according to claim 1, wherein the command includes reference timing information indicating that the timing of receiving the command is the reference timing.

5. The communication control method according to claim 1, wherein the command includes identification information of the IoT device.

6. The communication control method according to claim 5, wherein the resources are acquired based on identification information of the communication node.

7. The communication control method according to claim 1, wherein the resource information includes distribution information indicating information for distributing transmission timing and / or transmission frequency for each of the IoT devices.

8. The communication control method according to claim 7, wherein the distribution information includes a slot number upper limit value representing the maximum number of time slot numbers assigned to the IoT device, and a slot measurement timer value representing the time slot number for resetting a slot measurement timer used in the IoT device.

9. The communication control method according to claim 7, wherein the distribution information includes a channel number upper limit value representing an upper limit value of the number of channels used for transmission from the IoT device to the communication node, and channel spacing information representing the channel spacing.

10. The communication control method according to claim 1, wherein the resource information includes at least one of a transmission permission slot representing a time slot in which transmission is permitted and a transmission permission channel representing a channel in which transmission is permitted for each identification information of the IoT device.

11. The communication control method according to claim 1, wherein the resource information is written in advance in the memory of the IoT device, and the transmitting step includes the communication node transmitting resource information that the IoT device does not hold in the memory.

12. A communication node in a wireless communication system, comprising: a transmitter that transmits a transmission signal to an IoT (Internet of Things) device, wherein the transmission signal includes a command that includes resource information regarding resources used for transmission from the IoT device to the communication node.

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