Method and apparatus for detecting adjacent reader and device in backscattering-based ambient internet of things within wireless communication system

Abstract

A method and an apparatus for detecting an adjacent reader and a device in a backscattering-based ambient internet of things within a wireless communication system are disclosed. The method according to one embodiment of the present disclosure may comprise steps in which: a reader transmits a first signal to one or more devices; on the basis of backscattering for a carrier wave (CW) associated with the reader, the reader monitors, on one or more specific resources, one or more second signals transmitted from the one or more devices; and determining the proximity of each of the one or more devices on the basis of the one or more second signals.

Description

Method and device for detecting adjacent readers and devices of the ambient Internet of Things based on backscattering in a wireless communication system

[0001] The present disclosure relates to a wireless communication system, and more particularly, to a method and apparatus for detecting adjacent readers and devices of an ambient Internet of Things based on backscattering in a wireless communication system.

[0002] Mobile communication systems were developed to provide voice services while ensuring user activity. However, they have expanded beyond voice to include data services. Currently, explosive growth in traffic is leading to resource shortages and users' demand for higher-speed services, necessitating a more advanced mobile communication system.

[0003] Next-generation mobile communication systems must support explosive data traffic growth, dramatically increasing data rates per user, a vastly increased number of connected devices, ultra-low end-to-end latency, and high energy efficiency. To achieve these goals, various technologies are being studied, including dual connectivity, massive multiple input multiple output (MIMO), in-band full duplex, non-orthogonal multiple access (NOMA), super wideband support, and device networking.

[0004] The technical problem of the present disclosure is to provide a method and device for detecting adjacent readers and devices (or tags) of an ambient Internet of Things based on backscattering in a wireless communication system.

[0005] The technical problem of the present disclosure is to provide a method and device for determining proximity between a device (or tag) and a reader in an ambient Internet of Things based on backscattering.

[0006] The technical problems to be achieved in the present disclosure are not limited to the technical problems mentioned above, and other technical problems not mentioned can be clearly understood by a person having ordinary skill in the technical field to which the present disclosure belongs from the description below.

[0007] A method according to one embodiment of the present disclosure may include: transmitting a first signal to one or more devices by a reader; monitoring, by the reader, one or more second signals transmitted from the one or more devices on one or more specific resources based on backscattering of a carrier wave (CW) associated with the reader; and determining proximity to each of the one or more devices based on the one or more second signals.

[0008] A method according to another embodiment of the present disclosure may include: receiving one or more first signals from one or more readers by a device; transmitting a second signal to a particular reader by the device on a particular resource based on backscattering of a carrier wave (CW) associated with the particular reader among the one or more readers; and determining proximity to the particular reader based on whether the CW associated with the particular reader is detected for a predetermined time after transmitting the second signal.

[0009] According to the present disclosure, a method and device for detecting adjacent readers and devices (or tags) of an ambient Internet of Things based on backscattering in a wireless communication system can be provided.

[0010] According to the present disclosure, a method and device for determining proximity between a device (or tag) and a reader of a backscattering-based ambient Internet of Things can be provided.

[0011] The effects that can be obtained from the present disclosure are not limited to the effects mentioned above, and other effects that are not mentioned will be clearly understood by a person having ordinary skill in the art to which the present disclosure pertains from the description below.

[0012] The accompanying drawings, which are incorporated in and are part of the detailed description to aid in understanding the present disclosure, provide embodiments of the present disclosure and, together with the detailed description, describe the technical features of the present disclosure.

[0013] Figure 1 illustrates the structure of a wireless communication system to which the present disclosure can be applied.

[0014] FIG. 2 illustrates a frame structure in a wireless communication system to which the present disclosure can be applied.

[0015] FIG. 3 illustrates a resource grid in a wireless communication system to which the present disclosure can be applied.

[0016] FIG. 4 illustrates a physical resource block in a wireless communication system to which the present disclosure can be applied.

[0017] FIG. 5 illustrates a slot structure in a wireless communication system to which the present disclosure can be applied.

[0018] FIG. 6 illustrates physical channels used in a wireless communication system to which the present disclosure can be applied and a general signal transmission and reception method using the same.

[0019] FIG. 7 illustrates topologies that can be applied in a wireless communication system to which the present disclosure can be applied.

[0020] FIG. 8 is a drawing showing an example of a method performed by a leader according to the present disclosure.

[0021] FIG. 9 is a drawing showing an example of a method performed by a device according to the present disclosure.

[0022] FIG. 10 is a flowchart illustrating a procedure for an ambient IoT device to access a leader device according to one embodiment of the present disclosure.

[0023] FIG. 11 is a diagram for explaining a method for setting a symbol interval for AmIoT terminal communication according to one embodiment of the present disclosure.

[0024] FIG. 12 is a diagram for explaining a process in which an AmIoT terminal performs a backscattering operation according to one embodiment of the present disclosure.

[0025] FIG. 13 is a diagram for explaining a signaling procedure between an AmIoT terminal and a network node according to one embodiment of the present disclosure.

[0026] FIG. 14 illustrates a block diagram of a wireless communication device according to one embodiment of the present disclosure.

[0027] Hereinafter, preferred embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. The detailed description set forth below, together with the accompanying drawings, is intended to explain exemplary embodiments of the present disclosure and is not intended to represent the only embodiments in which the present disclosure may be practiced. The following detailed description includes specific details to provide a thorough understanding of the present disclosure. However, one of ordinary skill in the art will appreciate that the present disclosure may be practiced without these specific details.

[0028] In some cases, to avoid obscuring the concepts of the present disclosure, known structures and devices may be omitted or illustrated in block diagram form focusing on the core functions of each structure and device.

[0029] In the present disclosure, when a component is said to be "connected," "coupled," or "connected" to another component, this may include not only a direct connection but also an indirect connection in which another component exists between them. Furthermore, the terms "comprises" or "has" in the present disclosure specify the presence of the mentioned features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or groups thereof.

[0030] In this disclosure, terms such as “first,” “second,” etc. are used only to distinguish one component from another and are not used to limit the components, and do not limit the order or importance between the components unless specifically stated otherwise. Accordingly, within the scope of this disclosure, a first component in one embodiment may be referred to as a second component in another embodiment, and similarly, a second component in one embodiment may be referred to as a first component in another embodiment.

[0031] The terminology used herein is for the purpose of describing particular embodiments and is not intended to limit the scope of the claims. As used in the description of the embodiments and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly dictates otherwise. The term "and / or" as used herein may refer to any one of the associated enumerated items, or is meant to refer to and encompass any and all possible combinations of two or more of them. Furthermore, the use of " / " between words in this disclosure has the same meaning as "and / or" unless otherwise stated.

[0032] The present disclosure describes a wireless communication network or a wireless communication system, and operations performed in the wireless communication network may be performed in a process of controlling the network and transmitting or receiving a signal from a device (e.g., a base station) that manages the wireless communication network, or in a process of transmitting or receiving a signal to or between terminals connected to the wireless network.

[0033] In the present disclosure, transmitting or receiving a channel means transmitting or receiving information or a signal through the channel. For example, transmitting a control channel means transmitting control information or a signal through the control channel. Similarly, transmitting a data channel means transmitting data information or a signal through the data channel.

[0034] Hereinafter, downlink (DL) refers to communication from a base station to a terminal, and uplink (UL) refers to communication from a terminal to a base station. In downlink, a transmitter may be part of a base station, and a receiver may be part of a terminal. In uplink, a transmitter may be part of a terminal, and a receiver may be part of a base station. A base station may be expressed as a first communication device, and a terminal may be expressed as a second communication device. A base station (BS) may be replaced by terms such as a fixed station, Node B, eNB (evolved-NodeB), gNB (Next Generation NodeB), BTS (base transceiver system), access point (AP: Access Point), network (5G network), AI (Artificial Intelligence) system / module, RSU (road side unit), robot, drone (UAV: Unmanned Aerial Vehicle), AR (Augmented Reality) device, VR (Virtual Reality) device, etc.In addition, the terminal may be fixed or mobile, and may be replaced with terms such as UE (User Equipment), MS (Mobile Station), UT (user terminal), MSS (Mobile Subscriber Station), SS (Subscriber Station), AMS (Advanced Mobile Station), WT (Wireless terminal), MTC (Machine-Type Communication) device, M2M (Machine-to-Machine) device, D2D (Device-to-Device) device, vehicle, RSU (road side unit), robot, AI (Artificial Intelligence) module, UAV (Unmanned Aerial Vehicle), AR (Augmented Reality) device, VR (Virtual Reality) device, etc.

[0035] The following technologies can be used in various wireless access systems, such as CDMA, FDMA, TDMA, OFDMA, and SC-FDMA. CDMA can be implemented using wireless technologies such as UTRA (Universal Terrestrial Radio Access) or CDMA2000. TDMA can be implemented using wireless technologies such as GSM (Global System for Mobile communications) / GPRS (General Packet Radio Service) / EDGE (Enhanced Data Rates for GSM Evolution). OFDMA can be implemented using wireless technologies such as IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802-20, and E-UTRA (Evolved UTRA). UTRA is part of UMTS (Universal Mobile Telecommunications System). 3GPP (3rd Generation Partnership Project) LTE (Long Term Evolution) is a part of E-UMTS (Evolved UMTS) that uses E-UTRA, and LTE-A (Advanced) / LTE-A pro is an evolved version of 3GPP LTE. 3GPP NR (New Radio or New Radio Access Technology) is an evolved version of 3GPP LTE / LTE-A / LTE-A pro.

[0036] For clarity, the description is based on the 3GPP communication system (e.g., LTE-A, NR), but the technical idea of ​​the present disclosure is not limited thereto. LTE refers to technology after 3GPP TS (Technical Specification) 36.xxx Release 8. Specifically, LTE technology after 3GPP TS 36.xxx Release 10 is referred to as LTE-A, and LTE technology after 3GPP TS 36.xxx Release 13 is referred to as LTE-A pro. 3GPP NR refers to technology after TS 38.xxx Release 15. LTE / NR may be referred to as a 3GPP system. "xxx" refers to a standard document detail number. LTE / NR may be collectively referred to as a 3GPP system. For background technology, terms, abbreviations, etc. used in the description of the present disclosure, reference may be made to matters described in standard documents published prior to the present disclosure. For example, reference may be made to the following documents.

[0037] For 3GPP LTE, see TS 36.211 (Physical channels and modulation), TS 36.212 (Multiplexing and channel coding), TS 36.213 (Physical layer procedures), TS 36.300 (General description), and TS 36.331 (Radio resource control).

[0038] For 3GPP NR, see TS 38.211 (Physical channels and modulation), TS 38.212 (Multiplexing and channel coding), TS 38.213 (Physical layer procedures for control), TS 38.214 (Physical layer procedures for data), TS 38.300 (Overall description of NR and New Generation-Radio Access Network (NG-RAN)), and TS 38.331 (Radio Resource Control Protocol Specification).

[0039] Abbreviations for terms that may be used in this disclosure are defined as follows.

[0040] - BM: beam management

[0041] - CQI: Channel Quality Indicator

[0042] - CRI: Channel state information - reference signal resource indicator

[0043] - CSI: Channel State Information

[0044] - CSI-IM: Channel State Information - Interference Measurement

[0045] - CSI-RS: Channel state information - reference signal

[0046] - DMRS: Demodulation Reference Signal

[0047] - FDM: frequency division multiplexing

[0048] - FFT: fast Fourier transform

[0049] - IFDMA: interleaved frequency division multiple access

[0050] - IFFT: inverse fast Fourier transform

[0051] - L1-RSRP: Layer 1 reference signal received power

[0052] - L1-RSRQ: Layer 1 reference signal received quality

[0053] - MAC: Medium Access Control

[0054] - NZP: non-zero power

[0055] - OFDM: orthogonal frequency division multiplexing

[0056] - PDCCH: Physical downlink control channel

[0057] - PDSCH: Physical downlink shared channel

[0058] - PMI: precoding matrix indicator

[0059] - RE: resource element

[0060] - RI: Rank indicator

[0061] - RRC: Radio Resource Control

[0062] - RSSI: Received signal strength indicator

[0063] - Rx: Reception

[0064] - QCL: quasi co-location

[0065] - SINR: signal to interference and noise ratio

[0066] - SSB (or SS / PBCH block): Synchronization signal block (including primary synchronization signal (PSS), secondary synchronization signal (SSS), and physical broadcast channel (PBCH))

[0067] - TDM: Time Division Multiplexing

[0068] - TRP: transmission and reception point

[0069] - TRS: Tracking Reference Signal

[0070] - Tx: transmission

[0071] - UE: user equipment

[0072] - ZP: Zero Power

[0073] System General

[0074] As more and more communication devices demand greater communication capacity, the need for improved mobile broadband communications compared to existing radio access technologies (RATs) is emerging. Furthermore, massive machine type communications (MTC), which connects numerous devices and objects to provide diverse services anytime, anywhere, is also a key issue to be considered in next-generation communications. Furthermore, communication system design that considers reliability and latency-sensitive services / terminals is being discussed. Accordingly, the introduction of next-generation RATs that consider enhanced mobile broadband communication (eMBB), massive MTC (MMTC), and ultra-reliable and low latency communication (URLLC) is being discussed. For convenience, these technologies are referred to as NR in this disclosure. NR is an expression representing an example of 5G RAT.

[0075] A new RAT system, including NR, uses OFDM or a similar transmission scheme. The new RAT system may follow OFDM parameters different from those of LTE. Alternatively, the new RAT system may follow the existing LTE / LTE-A numerology but support a larger system bandwidth (e.g., 100 MHz). Alternatively, a single cell may support multiple numerologies. That is, terminals operating under different numerologies can coexist within a single cell.

[0076] A numerology corresponds to a single subcarrier spacing in the frequency domain. Different numerologies can be defined by scaling the reference subcarrier spacing by an integer N.

[0077] Figure 1 illustrates the structure of a wireless communication system to which the present disclosure can be applied.

[0078] Referring to Fig. 1, the NG-RAN consists of gNBs that provide NG-RA (NG-Radio Access) user plane (i.e., new AS (access stratum) sublayer / PDCP (packet data convergence protocol) / RLC (radio link control) / MAC / PHY) and control plane (RRC) protocol termination for UE. The gNBs are interconnected via Xn interfaces. The gNBs are also connected to the NGC (New Generation Core) via the NG interface. More specifically, the gNBs are connected to the AMF (Access and Mobility Management Function) via the N2 interface and to the UPF (User Plane Function) via the N3 interface.

[0079] FIG. 2 illustrates a frame structure in a wireless communication system to which the present disclosure can be applied.

[0080] NR systems can support multiple numerologies. Numerologies can be defined by subcarrier spacing and cyclic prefix (CP) overhead. Multiple subcarrier spacings can be derived by scaling the base (reference) subcarrier spacing by an integer N (or μ). Furthermore, even if it is assumed that very low subcarrier spacing is not used at very high carrier frequencies, the numerology used can be selected independently of the frequency band. Furthermore, NR systems can support various frame structures corresponding to multiple numerologies.

[0081] Below, we examine OFDM numerologies and frame structures that can be considered in NR systems. The various OFDM numerologies supported in NR systems can be defined as shown in Table 1 below.

[0082] μΔf=2 μ ·15 [kHz]CP015 Normal 130 Normal 260 Normal, Extended 3120 Normal 4240 Normal

[0083] NR supports multiple numerologies (or subcarrier spacing (SCS)) to support various 5G services. For example, when the SCS is 15 kHz, it supports a wide area in traditional cellular bands, when the SCS is 30 kHz / 60 kHz, it supports dense-urban, lower latency, and wider carrier bandwidth, and when the SCS is 60 kHz or higher, it supports a bandwidth larger than 24.25 GHz to overcome phase noise. The NR frequency band is defined by two types of frequency ranges (FR1, FR2). FR1 and FR2 can be configured as shown in Table 2 below. In addition, FR2 can mean millimeter wave (mmW).

[0084] Frequency Range Designation Corresponding Frequency Range Subcarrier Spacing FR1410MHz - 7125MHz 15, 30, 60kHz FR224250MHz - 52600MHz 60, 120, 240kHz

[0085] Regarding the frame structure in the NR system, the sizes of the various fields in the time domain are T c =1 / (Δf max ·N f ) is expressed as a multiple of the time unit. Here, Δf max =480·10 3 Hz, and N f =4096. Downlink and uplink transmissions are T f =1 / (Δf max N f / 100)·T c = It is organized into radio frames with a duration of 10ms. Here, each radio frame is T sf =(Δf max N f / 1000)·T c = It consists of 10 subframes with a duration of 1ms. In this case, there may be one set of frames for uplink and one set of frames for downlink. In addition, transmission in uplink frame number i from a terminal is T earlier than the start of the corresponding downlink frame from the terminal. TA =(N TA +N TA,offset )T c It should start before. For the subcarrier spacing configuration μ, slots are n within a subframe. s μ ∈{0,..., N slot subframe,μ-1} are numbered in increasing order, and n within a radio frame. s,f μ ∈{0,..., N slot frame,μ -1} are numbered in increasing order. One slot is N symb slot It consists of consecutive OFDM symbols, and N symb slot is determined by CP. Slot n in subframe s μ The start of OFDM symbol n in the same subframe s μ N symb slot are aligned temporally with the start of the OFDM signal. Not all terminals can transmit and receive simultaneously, which means that not all OFDM symbols in a downlink slot or uplink slot can be utilized.

[0086] Table 3 shows the number of OFDM symbols per slot in a general CP (N symb slot ), the number of slots per wireless frame (N slot frame,μ ), number of slots per subframe (N slot subframe,μ), and Table 4 shows the number of OFDM symbols per slot in the extended CP, the number of slots per radio frame, and the number of slots per subframe.

[0087] μN symb slot N slot frame,μ N slot subframe,μ01410111420221440431480841416016

[0088] μN symb slot N slot frame,μ N slot subframe,μ212404

[0089] FIG. 2 is an example when μ=2 (SCS is 60 kHz), and referring to Table 3, 1 subframe can include 4 slots. 1 subframe={1,2,4} slot illustrated in FIG. 2 is an example, and the number of slot(s) that can be included in 1 subframe is defined as in Table 3 or Table 4. In addition, a mini-slot can include 2, 4, or 7 symbols, or more or fewer symbols. With respect to physical resources in an NR system, antenna ports, resource grids, resource elements, resource blocks, carrier parts, etc. can be considered.

[0090] Hereinafter, the physical resources that can be considered in the NR system will be examined in detail. First, with respect to antenna ports, antenna ports are defined such that the channel through which a symbol on the antenna port is carried can be inferred from the channel through which another symbol on the same antenna port is carried. If the large-scale property of the channel through which a symbol on one antenna port is carried can be inferred from the channel through which a symbol on another antenna port is carried, then two antenna ports can be said to have a QC / QCL (quasi co-located or quasi co-location) relationship. Here, the large-scale property includes one or more of delay spread, Doppler spread, frequency shift, average received power, and received timing.

[0091] Fig. 3 illustrates a resource grid in a wireless communication system to which the present disclosure can be applied. Referring to Fig. 3, the resource grid is N in the frequency domain. RB μ N sc RB It consists of subcarriers, and one subframe is 14·2 μ It is described as an example, but not limited to, that it consists of OFDM symbols. In an NR system, the transmitted signal is N RB μ N sc RB One or more resource grids consisting of subcarriers and 2 μ N symb (μ) is described by OFDM symbols. Here, N RB μ ≤N RB max,μ is. The above NRB max,μ represents the maximum transmission bandwidth, which may vary not only between numerologies but also between uplink and downlink. In this case, one resource grid may be configured for each μ and antenna port p. Each element of the resource grid for μ and antenna port p is referred to as a resource element and is uniquely identified by an index pair (k, l').

[0092] Here, k=0,...,N RB μ N sc RB -1 is the index in the frequency domain, and l'=0,...,2 μ N symb (μ) -1 indicates the position of the symbol within the subframe. When referring to a resource element in a slot, an index pair (k,l) is used. Here, l=0,...,N symb μ -1. The resource element (k,l') for μ and antenna port p is a complex value a k,l' (p,μ) . If there is no risk of confusion or if a particular antenna port or numerology is not specified, the indices p and μ can be dropped, resulting in a complex value of a k,l' (p) or a k,l' This can be. Also, a resource block (RB) is N in the frequency domain. sc RB =12 is defined as consecutive subcarriers.

[0093] Point A serves as a common reference point of the resource block grid and is obtained as follows.

[0094] - offsetToPointA for the Primary Cell (PCell) downlink represents the frequency offset between point A and the lowest subcarrier of the lowest resource block overlapping the SS / PBCH block used by the UE for initial cell selection. It is expressed in resource block units assuming 15 kHz subcarrier spacing for FR1 and 60 kHz subcarrier spacing for FR2.

[0095] - absoluteFrequencyPointA represents the frequency-position of point A expressed as ARFCN (absolute radio-frequency channel number).

[0096] Common resource blocks (CRBs) are numbered from 0 upwards in the frequency domain for a subcarrier spacing setting μ. The center of subcarrier 0 of CRB 0 for a subcarrier spacing setting μ coincides with 'point A'. Common resource block number n in the frequency domain CRB μ The relationship between the resource elements (k, l) and the subcarrier spacing setting μ is given by the following mathematical expression 1.

[0097]

[0098] In Equation 1, k is defined relative to point A such that k = 0 corresponds to the subcarrier centered at point A. Physical resource blocks are numbered from 0 to N within the bandwidth part (BWP). BWP,i size,μ -Numbered from -1, where i is the number of BWP. Physical resource block n in BWP i PRB and common resource block n CRB The relationship between them is given by the mathematical formula 2 below.

[0099]

[0100] N BWP,i start,μ is a common resource block where BWP starts relative to common resource block 0.

[0101] FIG. 4 illustrates a physical resource block in a wireless communication system to which the present disclosure can be applied. FIG. 5 illustrates a slot structure in a wireless communication system to which the present disclosure can be applied.

[0102] Referring to FIGS. 4 and 5, a slot includes multiple symbols in the time domain. For example, in the case of a normal CP, one slot includes seven symbols, but in the case of an extended CP, one slot includes six symbols.

[0103] A carrier comprises multiple subcarriers in the frequency domain. An RB (Resource Block) is defined as multiple (e.g., 12) consecutive subcarriers in the frequency domain. A BWP (Bandwidth Part) is defined as multiple consecutive (physical) resource blocks in the frequency domain, and can correspond to a single numerology (e.g., SCS, CP length, etc.). A carrier can comprise up to N (e.g., 5) BWPs. Data communication is performed through activated BWPs, and only one BWP can be activated for a single terminal. Each element in the resource grid is referred to as a Resource Element (RE), to which one complex symbol can be mapped.

[0104] The NR system can support up to 400 MHz per component carrier (CC). If a terminal operating in such a wideband CC always operates with the radio frequency (RF) chip for the entire CC turned on, the terminal battery consumption may increase. Alternatively, when considering multiple use cases operating within a single wideband CC (e.g., eMBB, URLLC, Mmtc, V2X, etc.), different numerologies (e.g., subcarrier spacing, etc.) may be supported for each frequency band within the CC. Alternatively, each terminal may have different maximum bandwidth capabilities. Considering this, the base station can instruct the terminal to operate only in a portion of the bandwidth of the wideband CC, rather than the entire bandwidth. This portion of bandwidth is conveniently defined as the bandwidth part (BWP). A BWP can be composed of consecutive RBs on the frequency axis and can correspond to a single numerology (e.g., subcarrier spacing, CP length, slot / mini-slot interval).

[0105] Meanwhile, a base station can configure multiple BWPs even within a single CC configured for a terminal. For example, a BWP occupying a relatively small frequency domain can be configured in a PDCCH monitoring slot, while the PDSCH indicated by the PDCCH can be scheduled on a larger BWP.

[0106] Alternatively, if UEs are concentrated in a specific BWP, some UEs can be assigned to different BWPs for load balancing. Alternatively, considering frequency domain inter-cell interference cancellation between neighboring cells, some spectrum in the middle of the total bandwidth can be excluded and both BWPs can be assigned within the same slot. In other words, the base station can assign at least one DL / UL BWP to UEs associated with a wideband CC.

[0107] The base station can activate at least one DL / UL BWP among the DL / UL BWP(s) configured at a specific point in time (by L1 signaling or MAC CE (Control Element) or RRC signaling, etc.). In addition, the base station can instruct switching to another configured DL / UL BWP (by L1 signaling or MAC CE or RRC signaling, etc.). Alternatively, switching to a designated DL / UL BWP may be performed when a timer value expires based on a timer. In this case, the activated DL / UL BWP is defined as an active DL / UL BWP. However, since the UE may not receive the configuration for the DL / UL BWP when performing the initial access process or before the RRC connection is set up, the DL / UL BWP assumed by the UE in such a situation is defined as the initially active DL / UL BWP.

[0108] FIG. 6 illustrates physical channels used in a wireless communication system to which the present disclosure can be applied and a general signal transmission and reception method using the same.

[0109] In wireless communication systems, terminals receive information from a base station via the downlink and transmit it to the base station via the uplink. The information transmitted and received between the base station and terminals includes data and various control information, and various physical channels exist depending on the type and purpose of the information being transmitted and received.

[0110] When the terminal is powered on or enters a new cell, it performs an initial cell search operation, such as synchronizing with the base station (S601). To this end, the terminal receives a primary synchronization signal (PSS) and a secondary synchronization signal (PSS) from the base station to synchronize with the base station and obtain information such as a cell identifier (ID). Afterwards, the terminal can receive a physical broadcast channel (PBCH) from the base station to obtain broadcast information within the cell. Meanwhile, the terminal can receive a downlink reference signal (DL RS) during the initial cell search phase to check the downlink channel status.

[0111] A terminal that has completed an initial cell search can obtain more specific system information by receiving a physical downlink control channel (PDCCH) and a physical downlink shared channel (PDSCH) according to information contained in the PDCCH (S602).

[0112] Meanwhile, when accessing a base station for the first time or when there are no radio resources for signal transmission, the terminal may perform a random access procedure (RACH) with the base station (steps S603 to S606). To this end, the terminal may transmit a specific sequence as a preamble via the random access channel (RACH) (steps S603 and S605) and receive a response message to the preamble via the PDCCH and the corresponding PDSCH (steps S604 and S606). In the case of a contention-based RACH, a contention resolution procedure may additionally be performed.

[0113] The terminal that has performed the procedure described above can then perform PDCCH / PDSCH reception (S607) and physical uplink shared channel (PUSCH) / physical uplink control channel (PUCCH) transmission (S608) as general uplink / downlink signal transmission procedures. In particular, the terminal receives downlink control information (DCI) through the PDCCH. Here, DCI includes control information such as resource allocation information for the terminal, and its format varies depending on its intended use.

[0114] Meanwhile, the control information that the terminal transmits to the base station via the uplink or that the terminal receives from the base station includes downlink / uplink ACK / NACK (Acknowledgement / Non-Acknowledgement) signals, CQI (Channel Quality Indicator), PMI (Precoding Matrix Indicator), RI (Rank Indicator), etc. In the case of the 3GPP LTE system, the terminal can transmit the above-described control information such as CQI / PMI / RI via PUSCH and / or PUCCH.

[0115] Table 5 shows an example of the DCI format in the NR system.

[0116] DCI Format Utilization 0_0 Scheduling of PUSCH within a cell 0_1 Scheduling of one or multiple PUSCH within a cell, or indicating cell group (CG: cell group) downlink feedback information to the UE 0_2 Scheduling of PUSCH within a cell 1_0 Scheduling of PDSCH within a DL cell 1_1 Scheduling of PDSCH within a cell 1_2 Scheduling of PDSCH within a cell

[0117] Referring to Table 5, DCI formats 0_0, 0_1, and 0_2 may include resource information related to scheduling of PUSCH (e.g., UL / SUL (Supplementary UL), frequency resource allocation, time resource allocation, frequency hopping, etc.), transport block (TB) related information (e.g., MCS (Modulation Coding and Scheme), NDI (New Data Indicator), RV (Redundancy Version), etc.), HARQ (Hybrid - Automatic Repeat and request) related information (e.g., process number, DAI (Downlink Assignment Index), PDSCH-HARQ feedback timing, etc.), multi-antenna related information (e.g., DMRS sequence initialization information, antenna port, CSI request, etc.), power control information (e.g., PUSCH power control, etc.), and control information included in each DCI format may be predefined.

[0118] DCI format 0_0 is used for scheduling PUSCH in a cell. The information contained in DCI format 0_0 is transmitted after being scrambled with a CRC (cyclic redundancy check) by a C-RNTI (cell radio network temporary identifier, Cell RNTI), CS-RNTI (Configured Scheduling RNTI), or MCS-C-RNTI (Modulation Coding Scheme Cell RNTI).

[0119] DCI format 0_1 ​​is used to indicate scheduling of one or more PUSCHs in a cell, or configure grant (CG) downlink feedback information to the UE. The information contained in DCI format 0_1 ​​is CRC-scrambled and transmitted using the C-RNTI, CS-RNTI, SP-CSI-RNTI (Semi-Persistent CSI RNTI), or MCS-C-RNTI.

[0120] DCI format 0_2 is used for scheduling PUSCH in a cell. The information contained in DCI format 0_2 is CRC-scrambled and transmitted using C-RNTI, CS-RNTI, SP-CSI-RNTI, or MCS-C-RNTI.

[0121] Next, DCI formats 1_0, 1_1, and 1_2 may include resource information related to scheduling of PDSCH (e.g., frequency resource allocation, time resource allocation, virtual resource block (VRB)-physical resource block (PRB) mapping, etc.), transport block (TB) related information (e.g., MCS, NDI, RV, etc.), HARQ related information (e.g., process number, DAI, PDSCH-HARQ feedback timing, etc.), multi-antenna related information (e.g., antenna port, transmission configuration indicator (TCI), sounding reference signal (SRS) request, etc.), PUCCH related information (e.g., PUCCH power control, PUCCH resource indicator, etc.), and control information included in each DCI format may be predefined.

[0122] DCI format 1_0 is used for scheduling PDSCH in a DL cell. The information contained in DCI format 1_0 is CRC-scrambled and transmitted using C-RNTI, CS-RNTI, or MCS-C-RNTI.

[0123] DCI format 1_1 is used for scheduling PDSCH in a single cell. The information contained in DCI format 1_1 is CRC-scrambled and transmitted using C-RNTI, CS-RNTI, or MCS-C-RNTI.

[0124] DCI format 1_2 is used for scheduling PDSCH in a single cell. The information contained in DCI format 1_2 is CRC-scrambled and transmitted using C-RNTI, CS-RNTI, or MCS-C-RNTI.

[0125] Communication methods related to the Internet of Things (IoT)

[0126] IoT technology and its applications have recently attracted significant attention, and ongoing research is being conducted on technologies to install and connect a greater number of IoT devices (e.g., technologies to reduce the size, complexity, and power consumption of IoT devices). For example, scenarios, use cases, and key performance indicators (KPIs) for IoT devices within 3GPP-based communication systems (i.e., 3GPP IoT) are being discussed.

[0127] Specifically, 3GPP IoT can be applied to devices with ultra-low power consumption and ultra-low complexity. Furthermore, in terms of energy storage, 3GPP IoT can be applied to battery-less devices (i.e., devices without energy storage capacity) that rely on external energy sources or / and devices with limited energy storage capacity (e.g., devices that do not require manual battery replacement or recharging).

[0128] The device classifications described above, based on energy source, energy storage capacity, passive / active transmission, etc., can be discussed in relation to relevant use cases. The maximum power consumption of a device should be limited by the practical form factor for the intended use case, which may take into account the energy source.

[0129] 3GPP IoT can be applied to indoor / outdoor environments, base station characteristics (e.g., macro / micro / pico cell-based deployments), connection topology (e.g., nodes that can communicate with target devices such as base stations, terminals, relay terminals, repeaters, etc.), TDD / FDD and licensed / unlicensed spectrum frequency bands, coexistence of terminals and infrastructure in frequency bands of 3GPP technologies, and assumption of device-initiated / terminated traffic.

[0130] In one embodiment of the present disclosure, three types of IoT devices may be utilized.

[0131] - Device A: A device that does not store energy and does not generate independent signals (i.e., backscattering transmission).

[0132] - Device B: A device that stores energy and does not generate an independent signal (i.e., backscattering transmission), and use of the stored energy may include amplification of the reflected signal.

[0133] - Device C: A device that stores energy and generates an independent signal (i.e., includes an active RF component for transmission).

[0134] The present disclosure relates to a signal transmission and reception method of devices A and B that perform communication through backscattering transmission among three types of devices. However, this is only one embodiment, and various embodiments of the present disclosure can also be applied to device C.

[0135] Additionally, as an example of the present disclosure, at least one of the following four topologies may be applied, as illustrated in FIG. 7.

[0136] - Topology (1): BS <-> Ambient IoT Device

[0137] - Topology (2): BS <-> intermediate node <-> ambient IoT device

[0138] - Topology (3): BS <-> Assisting node <-> Ambient IoT device <-> BS

[0139] - Topology (4): UE <-> Ambient IoT Device

[0140] Here, the BS may be included in or replaced by the gNB, and may be a distribution unit (gNB-DU) of the gNB. Furthermore, the ambient IoT device may be replaced by a UE, a remote UE, a device, or a tag. The intermediate node (IN) may be at least one of a relay node, an integrated access backhaul (IAB) node, a relay UE, or a repeater of the network. In the present disclosure, the gNB and IN may be collectively referred to as a reader.

[0141] For example, for topology (1), the possibility of BS Rx and BS Tx may be included in different BSs. For topologies (2) and (3), the intermediate nodes and auxiliary nodes may be relay terminals, IAB nodes, repeaters, etc. that enable ambient IoT.

[0142] The present disclosure describes a method for transmitting and receiving signals in topologies 1 and 2, in which direct communication (i.e., mono-static communication) is performed between a base station (or / and intermediate node) and an IoT device among four topologies. However, this is only one embodiment, and the present disclosure may also be applied to topologies 3 and / or 4.

[0143] In the present disclosure, the direction from a gNB and / or an intermediate node (IN) to a device may be referred to as downlink (DL) or reader-to-tag (R2T) or reader-to-device (R2D). Additionally, the direction from a device to a gNB / IN may be referred to as uplink (UL) or tag-to-reader (T2R) or device-to-reader (D2R). The gNB / IN may transmit an R2T (or R2D) message or data information to the device via an R2T (R2D) signal, and the device may transmit a T2R (or D2R) message or data information to the gNB / IN via a T2R (or D2R) signal.

[0144] In describing the present disclosure, “ / ” means “and”, “or”, or “and / or”, depending on the context.

[0145] Below, the process of a terminal (e.g., an ambient IoT device or device) connecting to a leader BS / gNB / intermediate node (IN) is described.

[0146] FIG. 8 is a drawing showing an example of a method performed by a leader according to the present disclosure.

[0147] In step S810, the leader may transmit a first signal to one or more devices.

[0148] In some examples, the first signal may indicate or correspond to the identification information of the leader.

[0149] In some examples, the first signals of different leaders may be transmitted on different resources. For example, the first signal of a first leader may be transmitted on a first time / frequency resource, and the first signal of a second leader may be transmitted on a second time / frequency resource.

[0150] For example, the first signal described above may correspond to an R2D signal.

[0151] In step S820, the leader may monitor one or more second signals transmitted from one or more devices on one or more specific resources based on backscattering of a carrier wave (CW) associated with the leader.

[0152] A CW may correspond to a signal that induces a second signal. For example, a second signal may be backscattered by a device in response to a CW. This CW may be transmitted by the leader or by another node. For example, the CW may be transmitted periodically, or CWs with the same characteristics may appear periodically.

[0153] In some examples, a CW associated with a leader may indicate or correspond to the leader's identification information. For example, information indicating the identification of a specific leader may be overlaid on a specific CW.

[0154] In some examples, the location of a CW associated with a leader may correspond to the identification information of that leader.

[0155] In some examples, where multiple CWs exist, the positions (e.g., time / frequency positions) of these multiple CWs may correspond to the identification information of different leaders.

[0156] For example, the second signal may correspond to a D2R signal.

[0157] The different second signals may correspond to signals transmitted from different devices (by backscattering with respect to CW).

[0158] In some examples, the specific resource on which the second signal from a device is monitored may be determined based on the first resource from which the first signal is transmitted from the leader. Additionally or alternatively, the specific resource on which the second signal from a device is monitored may be determined based on the device identification information of the device.

[0159] For example, monitoring for a second signal may include attempting to detect / decode the second signal on a candidate resource (e.g., a resource from which the second signal may be transmitted).

[0160] In some examples, second signals from different devices may be monitored on different resources. A second signal from a first device may be monitored on a second resource, and a second signal from a second device may be monitored on a third resource. For example, the second resource and the third resource may be distinct resources in the time / frequency domain.

[0161] In some examples, each of the plurality of second signals may include information associated with a corresponding device. For example, a second signal from a first device may include information associated with the first device, and a second signal from a second device may include information associated with the second device. The information associated with a specific device may include one or more of identification information of the specific device or a random number selected by the device.

[0162] In some examples, the second signal from a device may be transmitted periodically and repeatedly. For example, after a predetermined time from the time the second signal is transmitted from a particular device, an additional second signal may be transmitted from that particular device based on backscattering of CW associated with the same reader. This additional second signal may correspond to one of the repetitions of the second signal transmitted periodically.

[0163] For example, a CW signal that induces a second signal may also be transmitted periodically.

[0164] In step S830, the leader may determine proximity to each of the one or more devices based on one or more second signals.

[0165] For example, the leader may determine that a first device is adjacent if a first second signal is detected, that a second device is adjacent if a second second signal is detected, or that a third device is not adjacent if a third second signal is not detected.

[0166] The method described in the example of FIG. 8 may be performed by the first wireless device (100) of FIG. 14, which will be described later. For example, the first wireless device (100) of FIG. 14 may correspond to a leader in various examples of the present disclosure. For example, one or more processors (102) of the first wireless device (100) of FIG. 14 may be configured to transmit a first signal from a reader to one or more devices via one or more transceivers (106), monitor one or more second signals transmitted from one or more devices based on backscattering of a carrier wave (CW) associated with the reader on one or more specific resources, and determine proximity to each of the one or more devices based on the one or more second signals. Furthermore, one or more memories (104) of the first wireless device (100) may store instructions for performing the method described in the example of FIG. 8 or the examples described below when executed by one or more processors (102).

[0167] FIG. 9 is a drawing showing an example of a method performed by a device according to the present disclosure.

[0168] In step S910, the device may receive one or more first signals from one or more readers.

[0169] In step S920, the device may transmit a second signal to a specific leader on a specific resource based on backscattering of a carrier wave (CW) associated with a specific leader among one or more leaders.

[0170] Here, the specific details of the first signal, the second signal, and the CW are the same as those described with reference to the example of Fig. 8, so redundant descriptions are omitted.

[0171] In step S930, the device may determine proximity to a particular leader based on whether a CW associated with the particular leader is detected for a predetermined time after the second signal transmission.

[0172] For example, if a device transmits a second signal in a backscattering manner for a CW associated with a first leader, and then a CW associated with the same first leader is detected / received (and thus the second signal may be transmitted in a backscattering manner), the first leader may be determined to be adjacent.

[0173] For example, if a device transmits a second signal in a backscattering manner for a CW associated with a second reader, and then no CW associated with the same second reader is detected / received (and thus no second signal is transmitted in a backscattering manner), the device may determine that the second reader is not adjacent.

[0174] The method described in the example of FIG. 9 may be performed by the second wireless device (200) of FIG. 14, which will be described later. For example, the second wireless device (200) of FIG. 14 may correspond to a device or tag in various examples of the present disclosure. For example, one or more processors (202) of the second wireless device (200) of FIG. 14 may be configured to receive one or more first signals from one or more readers through one or more transceivers (206), transmit a second signal to a specific reader through one or more transceivers (206) on a specific resource based on backscattering of a carrier wave (CW) associated with a specific reader among the one or more readers, and determine proximity to the specific reader based on whether a CW associated with the specific reader is detected for a predetermined time after the transmission of the second signal. Furthermore, one or more memories (204) of the second wireless device (200) may store instructions for performing the method described in the example of FIG. 9 or the examples described below when executed by one or more processors (202).

[0175] Hereinafter, a method for transmitting and receiving signals between an ambient IoT device and a (transmitting / receiving) reader device (e.g., BS, gNB, intermediate node, UE, etc.) will be specifically described. In the following embodiments, the ambient IoT device that performs communication with various reader devices may be expressed as a terminal (UE) or a device. That is, when the ambient IoT device is implemented as a UE, the reader device may be implemented as a BS, gNB, intermediate node, etc. As another example, when the ambient IoT device is implemented as a separate (IoT) device, the reader device may be implemented as a BS, gNB, intermediate node, UE, etc.

[0176] Example 1

[0177] Embodiment 1 relates to a process for an ambient IoT device to access a reader device. As an example of the present disclosure, FIG. 10 is a flowchart illustrating a process for an ambient IoT device to access a reader device. Specifically, the connection process may be comprised of an MSG0 transmission / reception process (Embodiment 1-1), an MSG1 transmission / reception process (Embodiment 1-2), an MSG2 transmission / reception process (Embodiment 1-3), an MSG3 transmission / reception process (Embodiment 1-4), an MSG4 transmission / reception process, and an MSG5 transmission / reception process (Embodiment 1-5).

[0178] Example 1-1

[0179] As an example of the present disclosure, a leader device may transmit MSG0 (e.g., a query signal or / and PDCCH order, etc.) to an ambient IoT device.

[0180] For example, if MSG0 is a query signal, the terminal can determine whether to transmit MSG1 based on MSG0. MSG0 can be used as a DL sync signal, such as PSS / SSS. For example, MSG0 can be reused as a DL sync signal, such as PSS / SSS, or defined as a new sync signal.

[0181] Ambient IoT devices can monitor MSG0 for carrier sensing-based connectivity. MSG0 may include information indicating whether the ambient IoT device can connect to the reader device (e.g., whether the ambient IoT device can transmit MSG1). For example, if MSG0 includes information indicating "busy" or / and "idle," the ambient IoT device may determine that it can transmit MSG1 within a certain period of time.

[0182] Additionally or alternatively, ambient IoT devices may use the carrier of another device to avoid collisions. For example, (ambient IoT) device 2 may detect the carrier transmitted by device 1 and avoid accessing it for a period of time after detecting the carrier.

[0183] At this time, MSG0 may include connection-related system information. For example, the connection-related system information may include a timer value for connection operations, information related to the time interval during which MSG1 transmission is possible (e.g., information related to the start time, length, window pattern, etc.). Additionally or alternatively, the connection-related system information may be transmitted via a separate MSG 0 for each specific device type, and the MSG 0 may indicate that the system information applies only to the specific device type.

[0184] Additionally or alternatively, MSG0 may include information for resolving conflicts. For example, MSG0 may include probability-based access information, UE ID-based access information, early indication-based access information, UE group / type-based access information, service / access type-based access information, etc.

[0185] Additionally or alternatively, an ambient IoT device that detects the transmission of a message (e.g., MSG0, MSG2, MSG4, etc.) to another device may not transmit MSG 1. However, if the ambient IoT device does not detect such a message for a certain period of time, the ambient IoT device may transmit MSG 1.

[0186] For example, an ambient IoT device can monitor MSG0 to determine whether access to the leader device is permitted. If MSG0 indicates "Busy" or "Idle," the ambient IoT device can access the leader device only after the "Idle" indication.

[0187] Example 1-2

[0188] The ambient IoT device can (re)transmit MSG1 to the reader device. For example, the ambient IoT device can (re)transmit MSG1 to the reader device using backscattering. The method described below can also be applied to transmitting and receiving messages subsequent to MSG1 (e.g., MSG 3 / 5).

[0189] As an example of the present disclosure, when MSG1 is transmitted in a slotted ALOHA manner, the ambient IoT device can transmit MSG1 at a time aligned with a specific time point (e.g., a transmission time of a DL sync signal or MSG0 transmitted by a reader device, a CW (carrier wave) transmission time, a backscattering transmission time (e.g., ambient IoT device A or B), etc.). The slotted ALOHA manner is a method of transmitting data by unit time (e.g., slot). As another example, the ambient IoT device can transmit MSG1 by selectively backscattering CW.

[0190] Additionally, MSG 1 may include a sequence for collision avoidance. The sequence for collision avoidance may be determined based on at least one of the options described below.

[0191] Option 1: Select a random sequence

[0192] Option 1A: Random sequence + early indication or UE group / type / service / connection type indication

[0193] When Option 1A is applied, the ambient IoT device may transmit MSG1 in the form of an early indication or UE group / type / service / connection type indication attached before or after a randomly selected sequence. In this case, the indication may correspond to a sequence according to Option 3, Option 4, or Option 5.

[0194] Option 1B: Select a random sequence from a cell-specific sequence pool.

[0195] When Option 1B is applied, the ambient IoT device may receive sequence-related information from the leader device or randomly select a sequence from a preset pool of sequences.

[0196] Option 2: Device-dedicated sequence

[0197] When Option 2 is applied, the ambient IoT device can receive sequence-related information from the leader device or transmit a preset device-specific sequence.

[0198] Option 3: Early Instruction-Based Sequence Selection

[0199] When Option 3 is applied, the ambient IoT device may transmit a sequence that maps to an early indication. Here, the early indication may collectively refer to an indicator that indicates the type or capability of the device (or terminal).

[0200] Option 4: UE Group / Type-Based Sequence Selection

[0201] When Option 4 applies, the ambient IoT device can transmit a sequence that is mapped to a UE group / type.

[0202] Option 5: Select a sequence based on service / connection type.

[0203] When Option 5 is applied, the ambient IoT device can transmit a sequence that maps to the service or connection type it is currently trying to access.

[0204] Option 6: Channel quality-based sequence

[0205] The ambient IoT device can measure the signal transmitted by the reader device and transmit MSG1 with a sequence mapped to the measured value. For example, if the measured value is less than or equal to threshold 1, the ambient IoT device can select a sequence from the first sequence pool. If the measured value is greater than threshold 1 but less than or equal to threshold 2, the ambient IoT device can select a sequence from the second sequence pool.

[0206] Based on the sequence, early indication, UE group / type, service / access type or channel quality level selected through at least one of the above-described options, the ambient IoT device can determine the (backscatter-based) transmission time and / or reception time of MSG1, MSG2, MSG3, MSG4 or / and MSG5. For example, based on the UE group / type or service / access type, a subsequent specific MSG transmission start time, a specific MSG reception start time, a specific MSG transmission interval or a specific MSG reception interval can be determined.

[0207] Additionally or alternatively, based on a sequence, early indication, UE group / type, service / access type, or channel quality level selected through at least one of the above-described options, the ambient IoT device may determine the transmission / reception resources / time / frequency of MSG1, MSG2, MSG3, MSG4, or / and MSG5. Accordingly, the ambient IoT device may transmit and receive MSG1, MSG2, MSG3, MSG4, or / and MSG5 based on the determined resources / time / frequency.

[0208] When an ambient IoT device transmits MSG 1, at least one of the methods described below may be applied to resolve a collision. That is, the ambient IoT device may distribute MSG1 transmissions using at least one of the methods described below.

[0209] Method 1: Distribution over multiple frequencies

[0210] Method 1 is a method in which an ambient IoT device selects one MSG1 frequency among multiple MSG1 frequencies and transmits MSG1 using the selected frequency. The ambient IoT device may configure multiple MSG1 frequencies (e.g., via MSG0), or multiple MSG1 frequencies may be preset / defined. Distribution methods via multiple frequencies may include a probability-based distribution method, a UE ID / sequence-based distribution method, a UE-only signaling method (based on preset configuration rather than for initial access), a channel quality-based distribution method, a beam / SSB index-based distribution method, and / or a UE group / type-based sequence selection method.

[0211] As an example of the present disclosure, when a probability-based distribution method is applied, the ambient IoT device may select the MSG1 frequency based on preset probability information and / or probability information received via MSG0. For example, the ambient IoT device may select a value between 0 and 1 immediately before transmitting MSG1. If the selected value exceeds a threshold value set by the reader device or a preset threshold value, the ambient IoT device may select a first frequency among the plurality of MSG1 frequencies. If the selected value is less than or equal to the threshold value set by the reader device or a preset threshold value, the ambient IoT device may select a second frequency among the plurality of MSG1 frequencies.

[0212] As an example of the present disclosure, when a UE ID / sequence based distribution scheme is applied, the ambient IoT device can select the MSG1 frequency according to the MSG1 sequence selected according to the above-described option or according to the pre-assigned UE ID.

[0213] As an example of the present disclosure, when a UE-only signaling scheme (based on pre-configuration rather than initial connection) is applied, the ambient IoT device can transmit MSG1 using a frequency determined according to the UE-only signal. The UE-only signal may be pre-stored configuration information or a message notified in advance by the reader device.

[0214] As an example of the present disclosure, when a channel quality-based distribution method is applied, an ambient IoT device can measure a signal transmitted by a reader device and transmit MSG1 using a frequency mapped to the measured value. Here, the measured signal can be a DL sync signal or MSG0. For example, if the measured value is less than or equal to a threshold value 1, the ambient IoT device can select a first frequency among a plurality of MSG1 frequencies. If the measured value is greater than or equal to a threshold value 1 and less than or equal to a threshold value 2, the ambient IoT device can select a second frequency among a plurality of MSG1 frequencies.

[0215] As another example, when a channel quality-based distribution method is applied, the ambient IoT device can measure a signal transmitted by the leader device and transmit an MSG1 resource mapped to the measured value. Here, the measured signal can be a DL sync signal or MSG0. For example, if the measured value is less than or equal to a threshold value of 1, the ambient IoT device can select the first resource among multiple resources. If the measured value is greater than the threshold value of 1 and less than or equal to the threshold value of 2, the ambient IoT device can select the second resource among multiple resources. The multiple resources can be set by the leader device or can be predefined.

[0216] As an example of the present disclosure, when a beam / SSB index-based distribution method is applied, the ambient IoT device may measure a beam RS or SSB transmitted by a reader device, and transmit MSG1 using a frequency or resource mapped to a best RS index, a best SSB index, or an RS / SSB greater than or equal to a threshold value. For example, if an SSB having an SSB index value of 0 is the best SSB or a measurement value of the SSB is greater than or equal to a threshold value, the ambient IoT device may select a first frequency / resource among the plurality of MSG1 frequencies / resources. For example, if an SSB having an SSB index value of 1 is the best SSB or a measurement value of the SSB is greater than or equal to a threshold value, the ambient IoT device may select a second frequency / resource among the plurality of MSG1 frequencies / resources.

[0217] As an example of the present disclosure, when a UE group / type based sequence selection method is applied, an ambient IoT device can select a frequency mapped to a UE group / type (among multiple MSG1 frequencies) and transmit MSG1 using the selected frequency.

[0218] As an example of the present disclosure, when a service / connection type-based sequence selection method is applied, the ambient IoT device can select a frequency (among multiple MSG1 frequencies) mapped to a service or connection type to which it is currently trying to connect, and transmit MSG1 using the selected frequency.

[0219] Method 2: Time-based distribution method

[0220] The time-based distribution method is a method in which the ambient IoT device selects a specific point in time / slot within a time interval for MSG1 transmission and transmits MSG1 within the selected specific point in time / slot. The ambient IoT device may set the time interval for MSG1 transmission (via MSG0), or the time interval for MSG1 transmission may be determined according to a predefined rule. The ambient IoT device may select the MSG1 transmission point in time / slot using at least one of the methods described below. In this case, the MSG1 transmission interval / point in time / slot may be determined as a point in time that is offset by a positive / negative amount from the CW transmission / reception point in time.

[0221] As an example of the present disclosure, when a probability-based distribution method is applied, the ambient IoT device may select a MSG1 transmission time / slot within the MSG 1 time interval based on preset probability information or probability information received from MSG0. For example, the ambient IoT device may select a specific value between 0 and 1 immediately before transmitting MSG1. If the selected specific value is preset by the reader device or exceeds a preset threshold, the ambient IoT device may select a first transmission time interval / transmission time / slot (within the time interval for MSG1 transmission). If the selected specific value is preset by the reader device or is less than or equal to a preset threshold, the ambient IoT device may select a second transmission time interval / transmission time / slot (within the time interval for MSG1 transmission). Then, the ambient IoT device may transmit MSG 1 in the selected transmission time interval / transmission time / slot.

[0222] As an example of the present disclosure, when a UE ID / sequence based distribution scheme is applied, the ambient IoT device can select an MSG1 transmission time point / slot within the time interval for MSG 1 transmission according to the MSG1 sequence selected according to the above-described option or the pre-assigned UE ID. For example, when the result value of sequence mode N or UE ID mod N is 0, the ambient IoT device can select the first transmission time interval / transmission time point / slot (within the time interval for MSG 1 transmission). When the result value of sequence mode N or UE ID mod N is 1, the ambient IoT device can select the second transmission time interval / transmission time point / slot (within the time interval for MSG 1 transmission).

[0223] As an example of the present disclosure, when a UE-only signaling scheme (based on pre-configuration rather than initial connection) is applied, the ambient IoT device can transmit MSG1 through a MSG1 transmission time interval / point / slot determined according to the UE-only signal. The UE-only signal may be pre-stored configuration information or a message notified in advance by the reader device.

[0224] As an example of the present disclosure, when a channel quality-based distribution scheme is applied, the ambient IoT device can measure a signal transmitted by the leader device and transmit MSG1 using a transmission time interval / point in time / slot within a time interval mapped to the measured value. Here, the measured signal can be a DL sync signal or MSG0. For example, if the measured value is less than or equal to a threshold value 1, the ambient IoT device can select the first time interval / point in time / slot (within the time interval for transmitting MSG1). If the measured value is greater than or equal to a threshold value 1 and less than or equal to a threshold value 2, the ambient IoT device can select the second time interval / point in time / slot (within the time interval for transmitting MSG1).

[0225] In another example of the present disclosure, when a channel quality-based distribution method is applied, the ambient IoT device can measure a signal transmitted by a leader device and transmit an MSG1 resource mapped to the measured value. Here, the measured signal can be a DL sync signal or MSG0. For example, if the measured value is less than or equal to a threshold value 1, the ambient IoT device can select a first resource among a plurality of resources. If the measured value is greater than the threshold value 1 and less than or equal to a threshold value 2, the ambient IoT device can select a second resource among the plurality of resources. Here, the resource can be determined by frequency and / or time.

[0226] As an example of the present disclosure, when a beam / SSB index-based distribution scheme is applied, the ambient IoT device can measure the beam RS or SSB transmitted by the reader device, and transmit MSG1 using a transmission time interval / point in time / slot or resource within a time interval mapped to a best RS index, a best SSB index, or an RS / SSB greater than or equal to a threshold value. For example, if an SSB having an SSB index value of 0 is the best SSB or a measurement value of the SSB is greater than or equal to a threshold value, the ambient IoT device can select a first transmission time interval / point in time / slot or resource (within a time interval for transmitting MSG1). For example, if an SSB having an SSB index value of 1 is the best SSB or a measurement value of the SSB is greater than or equal to a threshold value, the ambient IoT device can select a second transmission time interval / point in time / slot or resource (within a time interval for transmitting MSG1).

[0227] As an example of the present disclosure, when an energy storage based distribution scheme is applied, the ambient IoT device may measure the remaining energy storage level of the device and transmit MSG1 using a specific time interval / transmission point / slot within a time interval mapped to the measured value. For example, if the measured value (i.e., the energy storage level of the ambient IoT device) is less than or equal to a threshold value 1, the ambient IoT device may select the first transmission time interval / point / slot or resource (within the time interval for transmitting MSG1). If the measured value is greater than the threshold value 1 and less than or equal to a threshold value 2, the ambient IoT device may select the second transmission time interval / point / slot or resource (within the time interval for transmitting MSG1). In this case, the ambient IoT device may be configured to select a faster transmission time interval / point / slot as the remaining energy storage level decreases.

[0228] As an example of the present disclosure, when an energy storage-based distribution method is applied, an ambient IoT device can measure the remaining energy storage level of the device and transmit an MSG1 resource mapped to the measured value. For example, if the measured value (i.e., the energy storage level of the ambient IoT device) is less than or equal to a threshold value 1, the ambient IoT device can select a first resource among a plurality of resources. If the measured value is greater than the threshold value 1 and less than or equal to a threshold value 2, the ambient IoT device can select a second resource among the plurality of resources. Here, the resource can be determined by frequency / time.

[0229] As an example of the present disclosure, when a UE group / type-based sequence selection method is applied, an ambient IoT device can select a transmission time interval / point / slot mapped to a UE group / type (within a time interval for MSG1 transmission) and transmit MSG1 using the selected transmission time interval / point / slot.

[0230] As an example of the present disclosure, when a service / connection type-based sequence selection method is applied, the ambient IoT device can select a transmission time interval / point / slot mapped to a service or connection type to which it is currently trying to access (within the time interval for MSG1 transmission), and transmit MSG1 using the selected transmission time interval / point / slot.

[0231] As an example of the present disclosure, when a priority-based distribution scheme is applied, the ambient IoT device may select a transmission time interval / slot / point in time (for transmitting MSG1) based on the device priority or the priority of the connection to which it is currently trying to connect, and transmit MSG1 at the selected transmission time interval / slot / point in time. For example, in an access procedure with a high priority, or the device may select a short first transmission time interval / point in time / slot (within the time interval for transmitting MSG1), and transmit MSG1 using the first selected transmission time interval / point in time / slot. In an access procedure with a low priority, or the device may select a long second transmission time interval / point in time / slot or resource (within the time interval for transmitting MSG1), and transmit MSG1 using the second selected transmission time interval / point in time / slot.

[0232] An ambient IoT device can transmit MSG1 to a reader device according to at least one of the above-described methods. At this time, the terminal can probabilistically determine whether to actually transmit MSG1. For example, if the predefined / set probability value is a specific value (e.g., 0.3), the ambient IoT device can select a random number. If the random number is less than or equal to the specific value, the ambient IoT device can transmit MSG1. If the random number exceeds the specific value, the ambient IoT device can start a timer for back-off without transmitting MSG1.

[0233] After back-off (i.e., after the timer for back-off expires), the ambient IoT device may perform MSG1 retransmission according to at least one of the above-described methods. Additionally or alternatively, if MSG2 or / and MSG4 are not received, if MSG 2 or / and MSG4 do not contain a sequence or UE ID of the ambient IoT device, if MSG 2 or / and MSG4 do not indicate ACK, or / and if MSG 2 or / and MSG4 indicate NACK, the ambient IoT device may perform back-off.

[0234] After back-off (i.e., after the timer for back-off expires), the ambient IoT device can perform MSG1 retransmission according to at least one of the methods described above. The ambient IoT device can retransmit MSG1 after selecting / determining a back-off time (i.e., a timer value) according to at least one of the methods described below. The ambient IoT device can obtain the selectable back-off time values ​​from MSG 0, ​​MSG 2, or / and MSG 4, or from pre-stored information / system information.

[0235] As an example of the present disclosure, when a probability-based back-off time scheme is applied, the ambient IoT device may select a back-off time based on preset probability information or probability information received from MSG0. For example, the ambient IoT device may select a specific value between 0 and 1 immediately before transmitting MSG1. If the selected specific value is preset by the reader device or exceeds a preset threshold, the ambient IoT device may select a first back-off time (from among the plurality of back-off times). If the selected specific value is preset by the reader device or is less than or equal to a preset threshold, the ambient IoT device may select a second back-off time (from among the plurality of back-off times). Then, the ambient IoT device may transmit MSG 1 based on the selected back-off time.

[0236] As an example of the present disclosure, when a UE ID / sequence based back-off time scheme is applied, the ambient IoT device may select a back-off time according to a selected MSG1 sequence or a pre-assigned UE ID according to the above-described options. For example, when the result value of sequence mode N or UE ID mod N is 0, the ambient IoT device may select a first back-off time (from among a plurality of back-off times). When the result value of sequence mode N or UE ID mod N is 1, the ambient IoT device may select a second back-off time (from among a plurality of back-off times). Here, N may be equal to the number of selectable back-off times.

[0237] As an example of the present disclosure, when a UE-only signaling scheme (based on pre-configuration rather than initial connection) is applied, the ambient IoT device may transmit MSG1 based on a back-off time determined according to the UE-only signal. The UE-only signal may be pre-stored configuration information or a message notified in advance by the leader device.

[0238] As an example of the present disclosure, when a channel quality-based distribution method is applied, an ambient IoT device can measure a signal transmitted by a leader device and transmit MSG1 using a back-off time mapped to the measured value. Here, the measured signal can be a DL sync signal or MSG0. For example, if the measured value is less than or equal to a threshold value 1, the ambient IoT device can select a first back-off time (from among a plurality of back-off times). If the measured value is greater than or equal to a threshold value 1 and less than or equal to a threshold value 2, the ambient IoT device can select a second back-off time (from among a plurality of back-off times).

[0239] As an example of the present disclosure, when a beam / SSB index-based distribution scheme is applied, the ambient IoT device may measure the beam RS or SSB transmitted by the reader device, and transmit MSG1 using a back-off time mapped to a best RS index, a best SSB index, or an RS / SSB greater than or equal to a threshold value. For example, if an SSB having an SSB index value of 0 is the best SSB or a measurement value of the SSB is greater than or equal to a threshold value, the ambient IoT device may select a first back-off time (from among a plurality of back-off times). For example, if an SSB having an SSB index value of 1 is the best SSB or a measurement value of the SSB is greater than or equal to a threshold value, the ambient IoT device may select a second back-off time (from among a plurality of back-off times).

[0240] As an example of the present disclosure, when an energy storage-based distribution method is applied, an ambient IoT device may measure the remaining energy storage level of the device and transmit MSG1 using a back-off time mapped to the measured value. For example, if the measured value (i.e., the energy storage level of the ambient IoT device) is less than or equal to a threshold value 1, the ambient IoT device may select a first back-off time (from among a plurality of back-off times). If the measured value is greater than the threshold value 1 and less than or equal to a threshold value 2, the ambient IoT device may select a second back-off time (from among a plurality of back-off times). In this case, the ambient IoT device may be configured to select a shorter back-off time as the remaining energy storage level decreases.

[0241] As an example of the present disclosure, when a UE group / type-based sequence selection method is applied, an ambient IoT device can select a back-off time mapped to a UE group / type (among multiple back-off times) and transmit MSG1 using the selected back-off time.

[0242] As an example of the present disclosure, when a service / connection type-based sequence selection method is applied, the ambient IoT device can select a back-off time (among multiple back-off times) that is mapped to a service or connection type to which it is currently trying to connect, and transmit MSG1 using the selected back-off time.

[0243] As an example of the present disclosure, when a priority-based distribution scheme is applied, the ambient IoT device may select a back-off time based on the device priority or the priority of the connection to which it is currently trying to connect, and transmit MSG1 using the selected back-off time. For example, in an access procedure with a high priority, or the device may select a short first back-off time (from among a plurality of back-off times) that is mapped to the service or connection type to which it is currently trying to connect, and transmit MSG1 using the selected first back-off time. In an access procedure with a low priority, or the device may select a long second back-off time (from among a plurality of back-off times) that is mapped to the service or connection type to which it is currently trying to connect, and transmit MSG1 using the selected second back-off time.

[0244] Example 1-3

[0245] The ambient IoT device may receive MSG2 (from the reader device) after performing (re)transmission of MSG1. In one example of the present disclosure, MSG2 may include / indicate ACK and / or NACK information. For example, if the reader device successfully receives MSG1 and allows connection, MSG2 may include / indicate ACK. If the reader device does not successfully receive MSG1 or / and does not allow connection, MSG2 may include / indicate NACK.

[0246] For example, if MSG2 includes / indicates ACK, MSG2 may include at least one of information included in MSG1 (e.g., sequence information), transmission / reception resources of MSG1 (e.g., time / frequency resources), time / frequency for transmitting / receiving MSGs (e.g., MSG0, MSG1, MSG2, MSG3, MSG4, and / or MSG5, etc.), or CW time / frequency information for backscattering. If MSG2 includes / indicates NACK, MSG2 may include a back-off time.

[0247] Example 1-4

[0248] In one embodiment of the present disclosure, when an ACK including / indicating an ACK is received, the ambient IoT device may transmit MSG3 (to the reader device). For example, the ambient IoT device may transmit MSG3 in a backscattering manner. The selection of a time interval / point in time / frequency / resource for transmitting MSG3 may be determined / selected based on at least one of the transmission / reception time interval / point in time / frequency / resource selection methods of MSG2.

[0249] MSG3 may contain at least one of UE ID, sequence, early indication, UE group / type, connection type, RRC connection / resume request message for initial connection, and C-RNTI MAC CE for UE within RRC_CONNECTED.

[0250] Here, the UE ID (e.g., C-RNTI) may be scrambled, masked, or attached to all UL messages. The sequence may be part or all of the sequence selected for MSG1. In another example, the sequence may be part or all of a newly selected sequence using at least one of the MSG1 sequence selection methods described above. The early indication may include the device type (e.g., device A, device B, or device C) and / or other processing times. The RRC connection / resume request message may include the UE ID (e.g., s-TMSI or resumption ID), etc.

[0251] Example 1-5

[0252] An ambient IoT device that transmitted MSG 3 may receive MSG4 (from a reader device). MSG4 may include a UE ID (or / and contention resolution MAC CE) and / or sequence information. Here, the sequence may be selected / determined based on at least one of the MSG1 sequence selection methods described above.

[0253] If MSG4 contains the UE ID (or device ID) or sequence of the ambient IoT device, the ambient IoT device may transmit MSG5 (to the reader device).

[0254] For example, MSG5 may include terminal capability information. For example, the terminal capability information may include capability information related to device type (e.g., device type A, B, C), other processing times, early indication (e.g., device type, other processing times), terminal group / type, connection type, etc. Additionally or alternatively, MSG5 may include at least one of a UE ID, a sequence, and user data.

[0255] Example 2

[0256] Example 2 relates to a method for setting / defining a symbol duration for ambient IoT (AmIoT) terminal / device communication.

[0257] Considering the numerology of the NR system and the target data rate of the AmIoT system, the symbol interval for AmIoT communication can be determined according to at least one of the embodiments described below.

[0258] In describing the present disclosure, the NR system can be replaced with a (5G and / or 6G) wireless communication system (or a parent system / coexisting communication system). The (CP-)OFDM symbol can be replaced with an existing transmission time unit of the (5G and / or 6G) wireless communication system (or a parent system / coexisting communication system).

[0259] Example 2-1

[0260] N CF-OFDM symbol intervals of an NR system can be defined as a symbol interval for one AmIoT communication. The N value can be predefined or set / instructed to an AmIoT device.

[0261] Example 2-2

[0262] A CP-OFDM symbol interval of an NR system can be divided into M equal parts, and one of the M equally divided CP-OFDM symbol intervals can be defined as a symbol interval for AmIoT communication. Here, the value of M can be predefined or set / indicated by an AmIoT device. In this case, a CP interval can be included in a CF-OFDM symbol interval, but is not limited thereto. A CF-OFDM symbol interval may include only a part of a CP interval or may not include a CP interval.

[0263] Example 2-3

[0264] One or more OFDM symbols (e.g., predefined OFDM symbol sample values ​​(e.g., T C or T S ) can be defined as a sample group, and K sample group(s) can be defined as a symbol interval for one AmIoT communication. Here, the K value and the sample group determination method can be predefined or set / instructed to the AmIoT device.

[0265] One of Examples 2-1, 2-2 and 2-3 may be set / applied differently or set / applied commonly depending on the following elements.

[0266] - Use cases of AmIoT terminals (e.g., sensors, commands, inventory, positioning, etc.)

[0267] - Device type of AmIoT terminal, tag ID or / and topology of AMIoT communication

[0268] Example 3

[0269] It relates to a method for configuring a symbol interval for ambient IoT (AmIoT) terminal communication.

[0270] For communication between AmIoT terminals corresponding to device type A or B, both an energy transfer signal (ETS) for energy harvesting purposes and a backscattering signal (BSS) exchanged for backscattering communication after the AmIoT terminals receive the ETS may be required.

[0271] In order for the BSS signal transmitted by the base station or intermediate node (or, a separate UE device) to be efficiently received as a backscattered signal by the AmIoT device, it may be advantageous for the BSS signal to be configured as CW.

[0272] However, in order to be robust against inter-symbol interference (ISI) after generating a single OFDM symbol in an NR system, a CP may be attached to the front of the generated OFDM symbol, thereby configuring the final OFDM symbol. Due to the above-described characteristics, it may be difficult to construct a CW structure that maintains the same frequency component across multiple OFDM symbols, as illustrated in (a) of Fig. 11.

[0273] To overcome this, as illustrated in (b) of Fig. 11, by adjusting the phase for each OFDM symbol, the waveform can be configured so that the CW condition is satisfied across multiple OFDM symbols even if a CP is attached to the front of the OFDM symbol.

[0274] As described above, the pi / 2-BPSK (binary phase-shift keying) modulation method can be applied to control the phase for each CP. However, even when the Pi / 2-BPSK modulation method is applied, a problem may arise where the phase exceeds Pi / 2 or Pi / 4 due to the CP inserted in the middle. Therefore, a method that controls the phase for each CP while applying the Pi / 2-BPSK modulation method can be applied at the same time.

[0275] Pi / 2-BPSK modulation (and phase control per CP) makes sense in situations where data is transmitted by modulating it on a symbol-by-symbol basis, but Pi / 2-BPSK modulation (and phase control per CP) can only be applied to BSS (not ETS).

[0276] Additionally, when the above-described CW transmission method is applied, the unit and / or period in which CW is maintained can be set / instructed by the base station to the AmIoT device. For example, as illustrated in (b) of FIG. 11, when CW is maintained for every 2 OFDM symbols, 2 OFDM symbol interval information and / or the starting point of the interval (e.g., SFN#0 or every sub-frame) can be set / defined / instructed. Here, the interval information can be configured in units of OFDM symbols (or slots, subframes, or absolute time). For example, when the interval is set / instructed as 1 slot, the AmIoT device can assume that CW is maintained for at least a plurality of OFDM symbols within the same slot.

[0277] As another example of the present disclosure, a signal for an AmIoT terminal can be configured by repeating OFDM symbols without a CP (similar to the NR PRACH signal configuration). In this case, the base station can either abandon FDM with NR signals or perform FDM with existing NR signals after setting a guard band along the frequency axis.

[0278] Since the CW properties may not be maintained due to CP insertion, the CP interval may be used for other purposes. For example, during the CP interval (or during the symbol interval (or part of the symbol interval) for AmIoT terminal communication that includes the CP interval), the base station may transmit a known sequence, rather than data, to the AmIoT device, which may then use the sequence for time and / or frequency axis synchronization.

[0279] As described above, the CP interval (or the symbol interval for AmIoT terminal communication including the CP interval (or a part of the symbol interval)) for each symbol may not be utilized for other purposes. Therefore, the AmIoT device can set / receive specific time interval information. The interval information may be configured in units of OFDM symbols (or slots, sub-frames, absolute time) (e.g., X mesc, Y usec). For example, if information such as 1 slot is set, the AmIoT device can recognize that the CP interval (or the symbol interval for AmIoT terminal communication including the CP interval (or a part of the symbol interval)) for each slot is configured in a known sequence.

[0280] As described above, the method of maintaining CW across multiple OFDM symbols can be applied to embodiment 4-1 (i.e., an embodiment of a method of defining N CP-OFDM symbol intervals as a symbol interval for one AmIoT communication).

[0281] As described above, the CW transmission method can be applied to both ETS and BSS without distinction. As another example, since a higher PAPR can increase energy transfer efficiency, the CW transmission method can be applied only to BSS (and not to ETS).

[0282] Example 4

[0283] Example 4 relates to a frequency modulation method of a backscattering signal considering frequency diversity and / or (inter-cell) interference randomization.

[0284] As an example of the present disclosure, as illustrated in FIG. 12 (a), an AmIoT device that receives a CW (i.e., a BSS signal) of frequency F_c transmitted by a base station or intermediate node (or a separate terminal device) can modulate the frequency by applying F_gap. Then, the AmIoT device can transmit the backscattered signal / data to the base station or intermediate node (or a separate terminal device) via the frequency F_t.

[0285] It may be advantageous to increase the efficiency of IoT communications by reducing interference when signals are received from multiple base stations or intermediate nodes (or separate UE devices) that may be present in the vicinity from the receiving perspective of a single AmIoT device. Similarly, it may be advantageous to increase the efficiency of IoT communications by reducing interference when signals are received from multiple AmIoT devices from the receiving perspective of a base station or intermediate node (or separate UE device).

[0286] Additionally, fading on specific frequencies (e.g., F_c or F_t) in wireless channel environments can significantly degrade communication efficiency. Therefore, pursuing frequency diversification can help maximize the efficiency of IoT communications to overcome this issue. Below, we describe a method for determining F_c and / or F_t.

[0287] In consideration of the effect of reducing interference when signals are received from multiple base stations or intermediate nodes (or separate terminal devices) from the perspective of receiving a single AmIoT terminal, the position of F_c may be varied by considering all or some of a plurality of factors (e.g., (physical) cell index, sub-frame index, slot index, CP-OFDM symbol index of NR system, symbol index for AmIoT terminal communication, AmIoT device type).

[0288] Similarly, in consideration of the effect of reducing interference when signals are received from multiple AmIoT devices from a base station or intermediate node (or separate terminal device) receiving perspective, the position of F_t (relative to F_c) (or the size of F_gap) may be varied by taking into account all or some of a plurality of factors (e.g., AmIoT device index, sub-frame index, slot index, CP-OFDM symbol index of NR system, symbol index for AmIoT terminal communication, AmIoT device type, capability for (maximum) F_gap size of AmIoT, etc.).

[0289] As an example of F_t size variability considering the AmIoT device type, for a terminal of device type A, an F_t (or F_gap size) value within a maximum of X may be set / indicated, but for a terminal of device type B, an F_t (or F_gap size) value within a maximum of Y (>X) (or within a maximum of Y but equal to or greater than a minimum of X) may be set / indicated. Here, the values ​​of X and Y may be preset or defined.

[0290] Additionally or alternatively, taking into account the frequency diversification effect, CWs utilizing more than one F_c value at a time may be transmitted by the BSS (or / and ETS), even if the signal is from one base station or intermediate node (or separate terminal device).

[0291] Additionally or alternatively, a frequency hopping scheme may be applied to the position of F_c and / or the position of F_t (relative to F_c) (or the size of F_gap) considering both the frequency diversification effect and the interference randomization effect. For example, individual hopping offsets of F_hop 1 and F_hop 2 may be applied, and the change period and the size of the approximate value between the two offsets may be set / applied differently. For example, the F_c value at the {t+1}-th time may be determined from the F_c value at the t-th time by the formula "F_c(t+1) = F_c(t) + F_hop1 + F_hop2".

[0292] Here, the time t value can be determined by a combination of a sub-frame index, a slot index, a symbol index, etc. The range of the period and the size of the changed value of F_hop 1 and F_hop 2 can be set separately. For example, the period and size of one of F_hop 1 and F_hop 2 (e.g., F_hop 2) can be set to always be greater than the other (e.g., F_hop 1).

[0293] Additionally, the same hopping rules may apply depending on whether the signal is an ETS or a BSS. Alternatively, different hopping rules may apply (e.g., in BSS, both F_hop 1 and F_hop 2 are applied, whereas in ETS, only one offset is applied (e.g., F_hop2 is applied, but F_hop1 is not applied).

[0294] The positions / sizes of F_c, F_gap, F_t, F_hop1, and F_hop2 can be defined to have a multiple relationship with the SCS defined in the NR system by considering the numerology of NR. For example, the position of F_c can be set by recycling NR-ARFCN. The sizes of F_gap, F_hop1, and F_hop2 can be determined as multiples of a specific SCS (e.g., a separately set SCS, an SCS set in the activated / initial / default BWP, the largest or smallest SCS among multiple SCSs set in the associated carrier, etc.), or as multiples of 1 RB (e.g., 12 sub-carriers) based on the specific SCS.

[0295] Example 5

[0296] Example 5 relates to a time-domain modulation method of a backscattering signal considering frequency diversification and / or (inter-cell) interference randomization.

[0297] As an example of the present disclosure, as illustrated in (b) of FIG. 12, an AmIoT device that receives a signal (i.e., a BSS signal) from a base station or an intermediate node (or a separate terminal device) at time T_c can perform delayed transmission after time T_gap by applying T_gap. Accordingly, the AmIoT device can transmit the backscattered signal / data to the base station or an intermediate node (or a separate terminal device) at time T_t.

[0298] From the perspective of a single AmIoT terminal receiving, it may be beneficial to increase the efficiency of IoT communication by reducing interference when signals are received from multiple base stations or intermediate nodes (or separate terminal devices) that may be present in the vicinity.

[0299] Similarly, from the perspective of a base station or intermediate node (or separate terminal device), it may be beneficial to increase the efficiency of IoT communications by reducing interference when signals can be received from multiple AmIoT terminals. Furthermore, pursuing a time-diversification effect, similar to that in Example 4, in a wireless channel environment may help maximize the efficiency of IoT communications.

[0300] Below, a method for determining F_c, F_t, T_c and / or T_t is described taking into account the above-described advantages.

[0301] In consideration of the effect of reducing interference when signals are received from multiple base stations or intermediate nodes (or separate terminal devices) from the perspective of receiving a single AmIoT terminal, the position of T_c may be varied by considering all or some of a plurality of factors (e.g., (physical) cell index, sub-frame index, slot index, CP-OFDM symbol index of NR system, symbol index for AmIoT terminal communication, AmIoT device type).

[0302] Similarly, considering the effect of reducing interference when signals can be received from multiple AmIoT terminals from the perspective of receiving from a base station or intermediate node (or separate terminal device), the position of T_t (relative to T_c) (or the size of T_gap) may be varied by considering all or some of a plurality of factors (e.g., AmIoT device index, sub-frame index, slot index, CP-OFDM symbol index of NR system, symbol index for AmIoT terminal communication, AmIoT device type, capability for (maximum) T_gap size of AmIoT, etc.).

[0303] As an example of T_t size variability considering the AmIoT device type, for a terminal of device type A, a T_t (or T_gap size) value within a maximum of X can be set / indicated. And, for a terminal of device type B, a T_t (or T_gap size) value within a maximum of Y (>X) (or within a maximum of Y but greater than / exceeding a minimum of X) can be set / indicated. The X and Y values ​​can be separately set or predefined in advance.

[0304] Meanwhile, considering the time diversification effect, CWs utilizing multiple time points (i.e., multiple T_c values) can be transmitted as BSS (and / or ETS) even if it is the same signal (or modulated data) from one base station or intermediate node (or separate terminal device).

[0305] In addition, in the backscattered data transmission of the AmIoT terminal, the positions of one or more T_t (or the size of T_gap) corresponding to one T_c can be defined, and the AmIoT terminal can transmit a backscattered signal at the positions of multiple T_t for the same signal (or modulated signal).

[0306] Additionally or alternatively, time-varying values ​​may be applied to the position of T_c and / or the position of T_t (relative to T_c) (or the size of T_gap) to account for time-varying and / or interference randomization effects.

[0307] For example, the T_gap value at the {t+1}th time can be determined from the T_gap value at the tth time by the formula "T_gap(t+1) = T_gap(t) + T_hop".

[0308] Here, the time t value can be determined by a combination of sub-frame index, slot index, symbol index, etc. The period in which T_hop changes and the range of the size of the changed value can be separately set. As another example, the period in which T_hop changes and the size of the changed value can be defined as a value that changes randomly (within a specific set range).

[0309] Additionally or alternatively, the value of T_gap(t+1) at a particular time point {t+1} may be defined as a value that changes randomly (within a certain defined range) without any relation to T_gap(t) at a previous time point t.

[0310] Considering that a larger T_gap may lead to greater power consumption of AmIoT terminals, it may be beneficial in terms of fairness for the T_gap value to change randomly. Furthermore, the same rules may apply depending on whether the signal is ETS or BSS, but different rules (e.g., a rule that applies a different T_hop change period / value for BSS and a different T_hop change period / value for ETS) may apply.

[0311] The timing / size of the above-described T_c, T_gap, T_t, and T_hop can be defined to have a multiple relationship with one or more OFDM samples (e.g., predefined T_c or T_s) defined in the NR system, taking into account the numerology of NR.

[0312] FIG. 13 is a flowchart illustrating signaling between a terminal (e.g., a UE or an ambient IoT device) and a base station according to one embodiment of the present disclosure.

[0313] The base station can transmit a CW (i.e., a BSS signal) of frequency F_c to the terminal (S1310).

[0314] A terminal receiving a CW of frequency F_c can modulate (or / and backscatter) the frequency by applying F_gap determined according to various factors (e.g., UE ID, time index, device type, etc.) (S1320). Then, the terminal can transmit the backscattered data / signal to the base station via frequency F_t (i.e., F_c + F_gap) (S1330).

[0315] As described in the above-described embodiments, taking into account frequency diversification and / or interference randomization effects, the terminal may vary F_c and / or F_gap depending on the cell / UE ID, time index (e.g., subframe, slot, symbol, etc.), and device type.

[0316] By various embodiments described above, in a mixed situation where communication between multiple base stations and AmIot terminals is performed, backscattering-based communication can be efficiently performed by varying the time / frequency time using cell / UE ID, time index (e.g., subframe, slot, symbol, etc.), device type, etc. Accordingly, communication efficiency can be increased due to frequency diversification and / or interference randomization effects.

[0317] Example 6

[0318] The present embodiment relates to a method for a device to detect or identify a reader (e.g., gNB / IN) in its vicinity or adjacent to the device. The present embodiment also includes a method for a reader to detect or identify a device (or devices) in its vicinity or adjacent to the device.

[0319] The examples described in this embodiment may be applied as a method for a first reader to detect or identify a second reader(s), or for a second reader to detect or identify the first reader(s). For example, in the examples described below, if a device is replaced with a first reader (or a second reader) and a reader is replaced with a second reader (or a first reader), this may correspond to an example of mutual detection / identification between the first reader and the second reader.

[0320] Example 6-1

[0321] A device can detect / identify a leader (e.g., gNB / IN) based on a first signal transmitted by the leader (e.g., R2D signal).

[0322] The first signal may correspond to MSG0 (e.g., see MSG0 of Example 1). For example, the first signal may correspond to a message indicating a selection, or system information.

[0323] For example, a leader may transmit a signal indicating identification information (e.g., an ID) of the leader (e.g., itself) followed by a signal indicating MSG0 (e.g., a selection message or system information). The leader's identification information may or may not be included in the first signal.

[0324] As an example, the first signal may include a signal indicating selection or system information, an indicator indicating whether a reader ID is included, and reader ID information. These signals / information may be configured according to a specific order. For example, the indicator indicating whether a reader ID is included may include a bit string corresponding to a specific pattern. For example, if a reader ID is included in the first signal, the pattern of the indicator may be "10." For bit strings of other values ​​(e.g., indicating that a reader ID is not included), the reader ID information may be omitted from the first signal.

[0325] As another example, the first signal may include a signal indicating selection or system information, length information, and leader ID information. These signals / information may be configured according to a specific order. For example, the length information may indicate the length of the entire first signal, or may indicate the length of information following the length information. If the value of the length following the length information indicates a specific value greater than 0, the leader ID information may be included in the first signal. If the length following the length information corresponds to 0, the leader ID information may be omitted from the first signal.

[0326] As another example, the first signal may include a signal indicating selection or system information, a leader ID, and a termination indicator. These signals / information may be configured in a specific order. For example, the termination indicator may include a bit string corresponding to a specific pattern. For example, if the signal corresponds to termination, the pattern of the indicator may be "101011." If the value is other than this (i.e., if the signal does not correspond to termination), subsequent information may be further included in the first signal.

[0327] According to the present disclosure, the first signal may directly include the leader ID, or the first signal may be associated with the leader ID.

[0328] For example, MSG0 (e.g., a selection message or system information) may include a leader ID to distinguish the leader. For example, the selection message or system information may further include information indicating whether it is a gNB or an IN, and the gNB and the IN may be assigned to distinct leader ID spaces. For example, a leader having an ID belonging to a first leader ID space may correspond to a first leader (or gNB), and a leader having an ID belonging to a second leader ID space may correspond to a second leader (or IN). For this purpose, the gNB (or core network (CN) or AMF) may assign leader IDs to INs.

[0329] As an example of this, when leader ID space is allocated separately for gNB and IN, the leader ID of gNB can be allocated from among ID values ​​from 0 to 100, and the leader ID of IN can be allocated from among ID values ​​from 101 to 255.

[0330] As another example, if the leader ID space is shared between the gNB and the IN, any ID value from the entire leader ID space can be assigned to the gNB and the IN. For example, from the entire ID value range of 0-255, one ID value can be selected / assigned to each leader as the leader ID value without restriction, without distinguishing between the gNB and the IN.

[0331] The first signal (e.g., a selection message or system information) may include the leader ID information of the leader transmitting the first signal, but may also include the ID information of the surrounding leaders.

[0332] A device that receives a first signal associated with a specific reader ID can detect / identify the presence of a reader corresponding to the specific reader ID in its vicinity. The device may also determine that a reader corresponding to a reader ID not associated with the first signal does not exist in its vicinity.

[0333] Example 6-2

[0334] A reader can detect / identify a device based on a second signal (e.g., a D2R signal) transmitted by the device as a backscattering method for CW.

[0335] For example, CW can be transmitted by the leader or by other nodes. CW can be transmitted periodically or from specific locations (e.g., time resource locations, frequency resource locations, or time-frequency resource locations).

[0336] For example, a device may be configured / defined to respond only to a CW at a specific location. For example, a first device may transmit a second signal in a backscatter manner in response to a CW at a first location, and may not respond and transmit a second signal for a CW at a second location. A second device may transmit a second signal in a backscatter manner in response to a CW at a second location, and may not respond and transmit a second signal for a CW at a first location.

[0337] For example, a leader ID may be overlaid on a CW at a specific location. Additionally or alternatively, a leader ID may be periodically concatenated with the CW.

[0338] In this case, a signal / information about the leader ID may be transmitted following (e.g., concatenated with) the CW. The signal / information about the leader ID may not always include the leader ID, and the leader ID may be transmitted by concatenating / including it with the CW only under certain conditions / situations. For example, the leader ID may be included following the CW only when the leader transmits the CW. Alternatively, another node may change its leader ID for the sake of the neighboring leader(s) and transmit by concatenating it with the CW.

[0339] As an example, the CW may include an indicator indicating whether a leader ID is included and a leader ID. For example, these signals / information may be connected to the CW in a specific order. For example, the indicator indicating whether a leader ID is included may include a bit string corresponding to a specific pattern. For example, the pattern of the indicator when a leader ID is included in the CW may be "10." For bit strings of other values ​​(e.g., indicating that a leader ID is not included), the leader ID information may be omitted from the CW.

[0340] As another example, a CW may include length information and leader ID information. These signals / information may be connected to the CW in a specific order. For example, the length information may indicate the length of the entire CW or the length of information following the length information. If the length value following the length information indicates a specific value greater than 0, leader ID information may be included in the CW. If the length following the length information corresponds to 0, leader ID information may be omitted from the CW.

[0341] As another example, a CW may include a leader ID and a termination indicator. These signals / information may be linked to the CW in a specific order. For example, the termination indicator may include a bit string corresponding to a specific pattern. For example, if the indicator corresponds to termination, the pattern for the indicator may be "101011." For other values ​​(i.e., if the indicator does not correspond to termination), the CW may include additional information.

[0342] Alternatively, the leader ID may be transmitted overlaid on the CW periodically or intermittently (e.g., from one or more specific locations).

[0343] The device may start / restart a predetermined timer (e.g., Timer#1) whenever it receives a CW. The device may consider / assume / decide that the connection with the reader has failed / been lost if no (additional / subsequent) CW is detected for the predetermined period of time. The predetermined period of time may correspond, for example, to the time that the timer (e.g., Timer#1) is running. For example, if no CW is detected by the time the timer (e.g., Timer#1) expires, the device may consider / assume that the connection with the reader has failed / been lost (or may consider / assume / decide that the reader is not in the vicinity of the device).

[0344] Next, the device may include or concatenate its ID or random number into the second signal transmitted based on backscattering for the CW. For example, the random number may correspond to a value that can identify the device for a predetermined time period.

[0345] For example, a signal connected to or overlaid on CW may instruct / request the device to include / include either a device ID or a random number in the second signal and transmit it. For example, if the signal / information connected to / overlaid on CW is a first value (e.g., "010"), the device may include / include the device ID in the second signal and transmit it. Alternatively, if the signal / information connected to / overlaid on CW is a second value (e.g., "101"), the device may generate a random number and include / include it in the second signal and transmit it.

[0346] Here, the device may select one of the candidate resources to respond to the CW on a specific resource (i.e., transmit the second signal in a backscattering manner), as in the examples described below (e.g., embodiments 6-4 and / or 6-5). The response resource for each device may be preset, calculated based on device information, or relatively determined / set based on the resources of the CW.

[0347] Example 6-3

[0348] The device may periodically transmit a second signal (e.g., a D2R signal transmitted based on backscattering for CW). For example, the device may periodically transmit / backscattering the second signal to the leader.

[0349] The reader may start / restart a predetermined timer (e.g., Timer#2) whenever it receives a second signal. The reader may transmit a first signal (e.g., an R2D signal) and / or a CW if no (additional / subsequent) second signal is detected for a predetermined period of time. The predetermined period of time may correspond to, for example, the time that the timer (e.g., Timer#2) is running. For example, when the timer (e.g., Timer#2) expires, the reader may transmit the first signal / CW. For example, the reader may include a device ID and / or a random number of a specific device in the first signal / CW.

[0350] The leader may determine that the device is not present in the vicinity of the leader, or that no devices are present in the vicinity of the leader, if no second signal is received or no backscattering for CW is present for a predetermined period of time (e.g., until timer Timer#2 expires).

[0351] Alternatively, the device may start / restart a predetermined timer (e.g., Timer#3) each time it transmits the second signal. If the first signal / CW is not detected for a predetermined period of time (e.g., before Timer#3 expires), the device may then include the device ID and / or random number in the second signal corresponding to the response / backscatter to the first signal (e.g., R2D signal) and / or CW transmitted from the reader.

[0352] Example 6-4

[0353] The second signals transmitted from the devices may be transmitted on different frequency resources. The second signal may correspond to a D2R signal (e.g., a signal transmitted as backscattering for CW) received by the leader from the devices.

[0354] In the present disclosure, different frequency resources may correspond to resources that are distinguished at least in the frequency domain, such as different cells, different channels in the same cell, different frequency resource units within the same channel, or different bandwidth parts (BWPs) within the same cell.

[0355] In the examples below, Fx(x=1, 2, 3, ...) are assumed to be distinct frequency resources, and Ty(y=1, 2, 3, ...) are assumed to be distinct time resources.

[0356] A device may receive a first signal (e.g., an R2D signal) and / or a CW on F1, and in response transmit a second signal (e.g., a D2R signal backscattered with respect to the CW) by selecting one of the same or different frequency resources (e.g., F1, F2, F3) as F1. For example, it may be assumed that multiple devices belonging to the same group, or multiple devices adjacent to a leader, receive the first signal / CW and transmit the second signal in response thereto. In this case, for example, device 1 and device 2 may transmit the second signal on F1, and device 3 and device 4 may transmit the second signal on F2.

[0357] As an example of this, a frequency resource (e.g., a response frequency resource) for transmitting a second signal (or D2R signal) may be fixed for each device. For example, the response frequency resource may be set / indicated by the leader. Additionally or alternatively, the device may select / decide on one response frequency resource from among multiple candidates for response frequency resources.

[0358] As another example, the response frequency resource can be set / determined based on an offset value for the transmit / receive frequency resource of the first signal (e.g., R2D signal). For example, a device receiving the first signal on F3 can determine the response frequency resource for transmission of the second signal as a resource at a frequency position lower than F3 by an offset (e.g., one of F2 or F1). For example, a device receiving the first signal on F2 can determine the response frequency resource as a resource at a frequency position higher than F2 by an offset (e.g., one of F3, F4, or F5). This offset value can be mapped to the frequency resource of the first signal, indicated by the first signal, or determined based on the transmission time / point in time of the first signal.

[0359] As another example, the response frequency resource may be selected based on a predetermined probability. For example, assuming that all N response frequency resources mapped to a specific frequency resource on which a first signal (e.g., an R2D signal) is transmitted / received have the same probability of being selected (e.g., 1 / N), the N response frequency resources may each correspond to N ranges distinguished by the values ​​1 / N, 2 / N, 3 / N, ..., N / N. Accordingly, one of the N response frequency resources corresponding to a random value between 0 and 1 selected by the device may be selected. For example, if the value randomly determined by the device falls within the range between (k-1) / N and k / N, the k-th response frequency resource may be selected and the second signal may be transmitted. For example, if the device assigns values ​​of 1 / 4, 2 / 4, 3 / 4, and 4 / 4 to F1, F2, F3, and F4, respectively, and the randomly determined value is 0.6, the device may select F3, which is the third frequency between 2 / 4 and 3 / 4, as the response frequency to transmit the second signal (e.g., a D2R signal). Alternatively, the device may distinguish between F1, F2, F3, and F4 based on different probability values ​​(e.g., 0.18, 0.34, 0.61, and 1), and if the randomly determined value is 0.2, the device may select F2, which is between 0.18 and 0.34, as the response frequency to transmit the second signal (e.g., a D2R signal).

[0360] As another example, the response frequency resource may be determined based on the device ID (e.g., UE ID) or device group ID or specific code assigned to the device. For example, when a first signal (e.g., R2D signal) is received on F3, the device may calculate / determine the response frequency resource as a resource lower (or higher) than F3 by an offset. Here, the offset may be a value obtained by applying a modulo operation of a specific range value for the device ID / device group ID / specific code. Here, the range value may correspond to the range of the response frequency resource (or the range of the response frequency resource index). For example, when all candidates for the response frequency resource index are F1, F2, F3, and F4, a modulo 4 operation for the device ID / device group ID / specific code may be applied.

[0361] As another example, the reader may configure / instruct the response frequency resource on a per-device (or per-device group) basis. For example, if a device identified by the reader has immediately or previously received a first signal (or R2D signal) or transmitted a second signal (or D2R signal) on F3, the device may be configured to transmit a D2R signal on F3 even if it received the first signal on a frequency resource other than F3 (e.g., F1 or F2). For example, the reader may configure the device to configure the transmission resource of the second signal to a specific resource (e.g., F3) regardless of (or irrespective of) the reception resource of the first signal. Alternatively, if the device belongs to a specific device group or is assigned or stores a specific device group ID, the device may transmit the second signal (or D2R signal) on a resource mapped to the specific device group (or device group ID) regardless of (or irrespective of) the resource on which the device received the signal (or R2D signal). For example, if N response frequencies are available (i.e., the total number of candidate response frequency resources is N), and the result of applying mod N to the value of the device group ID is K, the device can transmit the second signal through the (K+1)th response frequency resource. For example, if N=4 and the device group ID value is 30, since 30 mod 4 = 2, the second signal (or D2R signal) can be transmitted using the third frequency resource, F3.

[0362] Example 6-5

[0363] The second signals transmitted from the devices may be transmitted on different time and frequency resources. The second signal may correspond to a D2R signal (e.g., a signal transmitted as backscattering for CW) received by the leader from the devices.

[0364] A device may receive a first signal (e.g., an R2D signal or a wake-up signal) at time F1 to time T1. In this case, a second signal may be transmitted on a time-frequency resource specified by a response frequency resource selected from among F1, F2, and F3, and a response time resource selected from among T1, T2, and T3.

[0365] For example, if all terminals within a terminal group or cell / coverage respond to one first signal, device 1 and device 2 may select F1 as a response frequency resource, and device 3 and device 4 may select F2 as a response frequency resource. Furthermore, device 1 may select T1 as a response time resource, and device 2 may select T2 as a response time resource. Accordingly, device 1 may transmit a second signal (e.g., a D2R signal) on the time-frequency resource specified by F1 and T1, and device 2 may transmit a second signal (e.g., a D2R signal) on the time-frequency resource specified by F1 and T2, i.e., on different time resources in the same frequency resource.

[0366] For example, in the various examples of selecting a response frequency resource described in Example 6-4, examples of selecting a response time resource by replacing the frequency resource (Fx) with a time resource (Ty) may be included within the scope of the present disclosure. In addition, the response time resource may be selected / determined based on one of the examples, and the response frequency resource may be selected / determined based on another of the examples. Alternatively, the response time resource and the response frequency resource may be selected / determined based on the same one of the examples.

[0367] In this way, the device can transmit a second signal at the selected / determined time-frequency resources.

[0368] In the examples of Embodiments 6-5 and 6-6 described above, examples of a device selecting / determining a resource from among predetermined candidate resources on which to transmit a second signal (e.g., a D2R signal) may include examples in which a leader monitors reception of a second signal from a device on the candidate resources and expects the second signal to be received on one of the candidate resources.

[0369] General devices to which the present disclosure may be applied

[0370] FIG. 14 illustrates a block diagram of a wireless communication device according to one embodiment of the present disclosure.

[0371] Referring to FIG. 14, the first device (100) and the second device (200) can transmit and receive wireless signals through various wireless access technologies (e.g., LTE, NR).

[0372] A first device (100) includes one or more processors (102) and one or more memories (104), and may additionally include one or more transceivers (106) and / or one or more antennas (108). The processor (102) controls the memories (104) and / or the transceivers (106), and may be configured to implement the descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed in the present disclosure.

[0373] For example, the processor (102) may process information in the memory (104) to generate first information / signal and then transmit a wireless signal including the first information / signal through the transceiver (106). In addition, the processor (102) may receive a wireless signal including second information / signal through the transceiver (106) and then store information obtained from signal processing of the second information / signal in the memory (104).

[0374] The memory (104) may be connected to the processor (102) and may store various information related to the operation of the processor (102). For example, the memory (104) may perform some or all of the processes controlled by the processor (102), or may store software code including commands for performing the descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in the present disclosure. Here, the processor (102) and the memory (104) may be part of a communication modem / circuit / chip designed to implement a wireless communication technology (e.g., LTE, NR). The transceiver (106) may be connected to the processor (102) and may transmit and / or receive wireless signals via one or more antennas (108). The transceiver (106) may include a transmitter and / or a receiver. The transceiver (106) may be used interchangeably with an RF (Radio Frequency) unit. In the present disclosure, a device may also mean a communication modem / circuit / chip.

[0375] The second device (200) includes one or more processors (202), one or more memories (204), and may further include one or more transceivers (206) and / or one or more antennas (208). The processor (202) controls the memories (204) and / or the transceivers (206), and may be configured to implement the descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed in the present disclosure. For example, the processor (202) may process information in the memory (204) to generate third information / signals, and then transmit a wireless signal including the third information / signals via the transceivers (206). In addition, the processor (202) may receive a wireless signal including fourth information / signals via the transceivers (206), and then store information obtained from signal processing of the fourth information / signals in the memory (204). The memory (204) may be connected to the processor (202) and may store various information related to the operation of the processor (202). For example, the memory (204) may perform some or all of the processes controlled by the processor (202), or may store software code including commands for performing the descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed in the present disclosure. Here, the processor (202) and the memory (204) may be part of a communication modem / circuit / chip designed to implement a wireless communication technology (e.g., LTE, NR). The transceiver (206) may be connected to the processor (202) and may transmit and / or receive wireless signals via one or more antennas (208). The transceiver (206) may include a transmitter and / or a receiver. The transceiver (206) may be used interchangeably with an RF unit. In the present disclosure, a device may also mean a communication modem / circuit / chip.

[0376] Hereinafter, the hardware elements of the device (100, 200) will be described in more detail. Although not limited thereto, one or more protocol layers may be implemented by one or more processors (102, 202). For example, one or more processors (102, 202) may implement one or more layers (e.g., functional layers such as PHY, MAC, RLC, PDCP, RRC, SDAP). One or more processors (102, 202) may generate one or more Protocol Data Units (PDUs) and / or one or more Service Data Units (SDUs) according to the descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in the present disclosure. One or more processors (102, 202) may generate messages, control information, data, or information according to the descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in the present disclosure. One or more processors (102, 202) can generate signals (e.g., baseband signals) including PDUs, SDUs, messages, control information, data or information according to the functions, procedures, proposals and / or methods disclosed in the present disclosure, and provide the signals to one or more transceivers (106, 206). One or more processors (102, 202) can receive signals (e.g., baseband signals) from one or more transceivers (106, 206) and obtain PDUs, SDUs, messages, control information, data or information according to the descriptions, functions, procedures, proposals, methods and / or operational flowcharts disclosed in the present disclosure.

[0377] One or more processors (102, 202) may be referred to as a controller, a microcontroller, a microprocessor, or a microcomputer. One or more processors (102, 202) may be implemented by hardware, firmware, software, or a combination thereof. For example, one or more Application Specific Integrated Circuits (ASICs), one or more Digital Signal Processors (DSPs), one or more Digital Signal Processing Devices (DSPDs), one or more Programmable Logic Devices (PLDs), or one or more Field Programmable Gate Arrays (FPGAs) may be included in one or more processors (102, 202). The descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed in this disclosure may be implemented using firmware or software, and the firmware or software may be implemented to include modules, procedures, functions, etc. The descriptions, functions, procedures, proposals, methods and / or operation flowcharts disclosed in this disclosure may be implemented using firmware or software configured to perform one or more processors (102, 202) or stored in one or more memories (104, 204) and driven by one or more processors (102, 202). The descriptions, functions, procedures, proposals, methods and / or operation flowcharts disclosed in this disclosure may be implemented using firmware or software in the form of codes, instructions and / or sets of instructions.

[0378] One or more memories (104, 204) may be coupled to one or more processors (102, 202) and may store various forms of data, signals, messages, information, programs, codes, instructions, and / or commands. The one or more memories (104, 204) may be configured as ROM, RAM, EPROM, flash memory, hard drives, registers, cache memory, computer-readable storage media, and / or combinations thereof. The one or more memories (104, 204) may be located internally and / or externally to the one or more processors (102, 202). Additionally, the one or more memories (104, 204) may be coupled to the one or more processors (102, 202) via various technologies, such as wired or wireless connections.

[0379] One or more transceivers (106, 206) can transmit user data, control information, wireless signals / channels, etc., as mentioned in the methods and / or flowcharts of the present disclosure, to one or more other devices. One or more transceivers (106, 206) can receive user data, control information, wireless signals / channels, etc., as mentioned in the descriptions, functions, procedures, proposals, methods and / or flowcharts of the present disclosure, from one or more other devices. For example, one or more transceivers (106, 206) can be connected to one or more processors (102, 202) and can transmit and receive wireless signals. For example, one or more processors (102, 202) can control one or more transceivers (106, 206) to transmit user data, control information, or wireless signals to one or more other devices. Additionally, one or more processors (102, 202) may control one or more transceivers (106, 206) to receive user data, control information, or wireless signals from one or more other devices. Additionally, one or more transceivers (106, 206) may be coupled to one or more antennas (108, 208), and one or more transceivers (106, 206) may be configured to transmit and receive user data, control information, wireless signals / channels, or the like, as referred to in the descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed in the present disclosure, via one or more antennas (108, 208). In the present disclosure, one or more antennas may be multiple physical antennas or multiple logical antennas (e.g., antenna ports). One or more transceivers (106, 206) can convert received user data, control information, wireless signals / channels, etc. from RF band signals to baseband signals in order to process the received user data, control information, wireless signals / channels, etc. using one or more processors (102, 202).One or more transceivers (106, 206) may convert user data, control information, wireless signals / channels, etc. processed by one or more processors (102, 202) from baseband signals to RF band signals. For this purpose, one or more transceivers (106, 206) may include an (analog) oscillator and / or filter.

[0380] The embodiments described above are combinations of components and features of the present disclosure in a predetermined form. Each component or feature should be considered optional unless explicitly stated otherwise. Each component or feature may be implemented without being combined with other components or features. Furthermore, it is also possible to form embodiments of the present disclosure by combining some components and / or features. The order of operations described in the embodiments of the present disclosure may be changed. Some components or features of one embodiment may be included in another embodiment or may be replaced with corresponding components or features of another embodiment. It is self-evident that claims that do not have an explicit citation relationship in the patent claims may be combined to form embodiments or incorporated as new claims through post-application amendments.

[0381] It will be apparent to those skilled in the art that the present disclosure may be embodied in other specific forms without departing from the essential characteristics thereof. Therefore, the above detailed description should not be construed as limiting in any respect, but rather as illustrative. The scope of the present disclosure should be determined by a reasonable interpretation of the appended claims, and all modifications within the scope of equivalents of the present disclosure are intended to be included within the scope of the present disclosure.

[0382] The scope of the present disclosure includes software or machine-executable instructions (e.g., an operating system, an application, firmware, a program, etc.) that cause operations according to the methods of various embodiments to be executed on a device or a computer, and a non-transitory computer-readable medium having such software or instructions stored thereon and executable on the device or computer. Instructions that can be used to program a processing system to perform the features described in the present disclosure can be stored on / in a storage medium or a computer-readable storage medium, and a computer program product including such a storage medium can be used to implement the features described in the present disclosure. The storage medium can include, but is not limited to, high-speed random access memory, such as DRAM, SRAM, DDR RAM, or other random access solid state memory devices, and can include non-volatile memory, such as one or more magnetic disk storage devices, optical disk storage devices, flash memory devices, or other non-volatile solid state storage devices. The memory optionally includes one or more storage devices remotely located from the processor(s). The memory or, alternatively, the non-volatile memory device(s) within the memory comprise a non-transitory computer-readable storage medium. The features described in this disclosure may be incorporated into software and / or firmware stored on any of the machine-readable media, which may control the hardware of the processing system and allow the processing system to interact with other mechanisms that utilize results according to embodiments of the present disclosure. Such software or firmware may include, but is not limited to, application code, device drivers, operating systems, and execution environments / containers.

[0383] Here, the wireless communication technology implemented in the device (100, 200) of the present disclosure may include not only LTE, NR, and 6G, but also Narrowband Internet of Things for low-power communication. At this time, for example, NB-IoT technology may be an example of LPWAN (Low Power Wide Area Network) technology, and may be implemented with standards such as LTE Cat NB1 and / or LTE Cat NB2, and is not limited to the above-described names. Additionally or alternatively, the wireless communication technology implemented in the device (100, 200) of the present disclosure may perform communication based on LTE-M technology. At this time, for example, LTE-M technology may be an example of LPWAN technology, and may be called by various names such as eMTC (enhanced Machine Type Communication). For example, LTE-M technology can be implemented by at least one of various standards such as 1) LTE CAT 0, 2) LTE Cat M1, 3) LTE Cat M2, 4) LTE non-BL (non-Bandwidth Limited), 5) LTE-MTC, 6) LTE Machine Type Communication, and / or 7) LTE M, and is not limited to the above-described names. Additionally or alternatively, the wireless communication technology implemented in the device (100, 200) of the present disclosure can include at least one of ZigBee, Bluetooth, and Low Power Wide Area Network (LPWAN) considering low-power communication, and is not limited to the above-described names. For example, ZigBee technology can create personal area networks (PAN) related to small / low-power digital communication based on various standards such as IEEE 802.15.4, and can be called by various names.

[0384] The method proposed in this disclosure is explained with a focus on examples applied to 3GPP LTE / LTE-A and 5G systems, but can be applied to various wireless communication systems in addition to 3GPP LTE / LTE-A and 5G systems.

Claims

1. A step of transmitting a first signal to one or more devices by a reader; A step of monitoring, by the leader, one or more second signals transmitted from the one or more devices on one or more specific resources based on backscattering of a carrier wave (CW) associated with the leader; and A method comprising the step of determining proximity to each of the one or more devices based on the one or more second signals.

2. In paragraph 1, A method wherein the CW associated with the leader indicates identification information of the leader or corresponds to identification information of the leader.

3. In paragraph 2, A method in which information indicating the identification information of the above leader is overlaid on the above CW.

4. In paragraph 1, A method wherein the location of the CW associated with the leader corresponds to the identification information of the leader.

5. In paragraph 1, A method in which the CW associated with the above leader is transmitted periodically.

6. In paragraph 1, A method wherein, based on the existence of multiple CWs, the locations of the multiple CWs correspond to identification information of different leaders.

7. In paragraph 1, The above CW is transmitted by the leader or by another node.

8. In paragraph 1, A method wherein the one or more specific resources from which the one or more second signals are monitored are based on one or more of the identification information of the first resource from which the first signal from the leader is transmitted or the one or more devices.

9. In paragraph 8, A second signal from the first device is monitored on the second resource, A method wherein a second signal from a second device is monitored on a third resource.

10. In paragraph 9, A method wherein the second resource and the third resource are distinguished in at least one of the time domain and the frequency domain.

11. In paragraph 1, A method wherein said one or more second signals each include associated information of said one or more devices.

12. In paragraph 11, A method wherein information associated with a specific device comprises at least one of identification information of the specific device or a random number selected by the specific device.

13. In paragraph 1, A method wherein, after a predetermined time from the time at which the second signal is transmitted from a specific device among the one or more devices, an additional second signal is transmitted from the specific device based on backscattering for the CW associated with the leader.

14. In paragraph 13, A method wherein the additional second signal corresponds to one of the repetitions of the second signal transmitted based on a predetermined period.

15. In paragraph 1, A method wherein the first signal indicates identification information of the leader or corresponds to identification information of the leader.

16. In paragraph 1, The first signal from the above leader is transmitted on the first resource, A method wherein a first signal from another leader is transmitted on a second resource.

17. In paragraph 1, The above first signal is an R2D (reader-to-device) signal, A method wherein the second signal is a D2R (device-to-reader) signal.

18. One or more transceivers; and comprising one or more processors connected to said one or more transceivers, One or more of the above processors: Transmitting a first signal from a reader to one or more devices via said one or more transceivers; Monitoring one or more second signals transmitted from one or more devices based on backscattering of a carrier wave (CW) associated with the leader on one or more specific resources; and A reader configured to determine proximity to each of said one or more devices based on said one or more second signals.

19. A step of receiving one or more first signals from one or more readers by the device; transmitting a second signal to a specific leader by the device on a specific resource based on backscattering of a carrier wave (CW) associated with the specific leader among the one or more leaders; and A method comprising the step of determining proximity to the specific leader based on whether the CW associated with the specific leader is detected for a predetermined time after the second signal transmission.

20. One or more transmitters and receivers; and comprising one or more processors connected to said one or more transceivers, One or more of the above processors: Receiving one or more first signals from one or more readers via one or more transceivers; Transmitting a second signal to a specific leader through the one or more transceivers on a specific resource based on backscattering of a carrier wave (CW) associated with a specific leader among the one or more leaders; and A device configured to determine proximity to the specific leader based on whether the CW associated with the specific leader is detected for a predetermined time after the second signal transmission.

21. One or more processors; and A processing device comprising one or more computer memories operatively connected to said one or more processors and storing instructions for performing a method according to any one of claims 1 to 17 based on execution by said one or more processors.

22. One or more non-transitory computer-readable media storing one or more instructions that are executed by one or more processors to control the performance of a method according to any one of claims 1 to 17.

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