Method and device for transmitting signals in wireless communication system

Abstract

This device for performing wireless communication in a wireless communication system may comprise a communication module, and a processor for controlling the communication module. The processor of the device may receive a physical reader-to-device channel (PRDCH) and transmit a physical device-to-reader channel (PDRCH) in response to the PRDCH, wherein the PDRCH is transmitted at a time point after a first interval from a time point at which reception of the PRDCH is completed, and the first interval is determined on the basis of a first offset determined on the basis of a chip length of the PDRCH.

Description

A method for transmitting a signal in a wireless communication system and an apparatus for the same

[0001] This specification relates to a wireless communication system, and more specifically to a method for transmitting a signal and an apparatus for the same.

[0002] Since the commercialization of 4G (4th generation) communication systems, efforts have been made to develop new 5G (5th generation) communication systems to meet the increasing demand for wireless data traffic. 5G communication systems are referred to as beyond 4G network communication systems, post-LTE systems, or NR (new radio) systems. To achieve high data transmission rates, 5G communication systems include systems operating in the mmWave band above 6 GHz, and implementations at base stations and terminals are being considered to include communication systems operating in the frequency band below 6 GHz in order to secure coverage.

[0003] 3GPP (3rd generation partnership project) NR systems improve network spectrum efficiency, enabling telecommunications operators to provide more data and voice services within a given bandwidth. Therefore, 3GPP NR systems are designed to meet the demands for high-speed data and media transmission in addition to supporting high-volume voice. The advantages of NR systems include high throughput, low latency, support for FDD (frequency division duplex) and TDD (time division duplex), an enhanced end-user experience, and low operating costs due to a simple architecture, all within the same platform.

[0004] For more efficient data processing, dynamic TDD in NR systems may use a method that varies the number of Orthogonal Frequency Division Multiplexing (OFDM) symbols available for uplink and downlink based on the direction of data traffic from cell users. For example, when a cell's downlink traffic is greater than its uplink traffic, the base station may allocate multiple downlink OFDM symbols to a slot (or subframe). Information regarding the slot configuration must be transmitted to the terminals.

[0005] In order to mitigate path loss of radio waves in the ultra-high frequency band and increase the transmission distance of radio waves, beamforming, massive array multiple input / output (massive MIMO), full-dimensional multiple input / output (full-dimensional MIMO, FD-MIMO), array antenna, analog beamforming, hybrid beamforming combining analog beamforming and digital beamforming, and large-scale antenna technologies are being discussed in 5G communication systems. In addition, to improve the network of the system, technology development is underway in 5G communication systems regarding advanced small cells, advanced small cells, cloud radio access networks (cloud RAN), ultra-dense networks, device-to-device communication (D2D), vehicle-to-everything communication (V2X), wireless backhaul, non-terrestrial network communication (NTN), moving networks, cooperative communication, CoMP (coordinated multi-points), and interference cancellation.In addition, advanced coding modulation (ACM) methods such as FQAM (hybrid FSK and QAM modulation) and SWSC (sliding window superposition coding), as well as advanced access technologies such as FBMC (filter bank multi-carrier), NOMA (non-orthogonal multiple access), and SCMA (sparse code multiple access) are being developed in 5G systems.

[0006] TDD is widely used in commercial deployment scenarios for NR systems. In TDD, time-domain resources are divided into downlink and uplink resources. The limited allocation of uplink resources in the time domain results in reduced uplink coverage, increased latency, and reduced capacity. To overcome these drawbacks of the existing TDD method, a method to support simultaneous downlink and uplink transmission and reception at the base station—namely, a full-duplex communication method—is being discussed. Specifically, a subband non-overlapping full-duplex communication method within the existing TDD band is being discussed.

[0007] Dynamic and flexible downlink and uplink resource allocation, cross-link interference (CLI) handling, and remote interference management (RIM) in the time domain were introduced in Rel-16 for NR TDD systems. Nevertheless, the need for CLI handling between base stations of the same or different operators to implement dynamic and flexible TDD in commercial networks has been raised and is being further discussed in subsequent releases. Depending on the deployment scenario, CLI between base stations can occur due to adjacent-channel CLI, co-channel CLI, or both adjacent-channel and co-channel CLI.

[0008] Research on the aforementioned NR TDD system is being discussed with the aim of identifying the feasibility and solutions for the evolution of duplex communication schemes in the aforementioned areas to provide enhanced uplink coverage, reduced latency, improved system capacity, and improved configuration flexibility for the implementation of NR TDD in unpaired spectrum. Additionally, regulatory aspects are being discussed for the deployment of enhanced duplex communication schemes considering potential constraints in unpaired spectrum.

[0009] The purpose of this specification is to provide a method for transmitting a signal and an apparatus for the same.

[0010] The present specification provides a device for performing wireless communication in a wireless communication system and a method for performing wireless communication.

[0011] Specifically, the device may include a communication module; and a processor that controls the communication module. The processor receives a PRDCH (physical reader-to-device channel) and transmits a PDRCH (physical device-to-reader channel) in response to the PRDCH, wherein the PDRCH is transmitted at a time after a first interval from the time when the reception of the PRDCH is completed, and the first interval may be determined based on a first offset determined based on the chip length of the PDRCH.

[0012] Additionally, a method performed by a terminal performing wireless communication in a wireless communication system according to the present specification includes the steps of: receiving a PRDCH (physical reader-to-device channel); and transmitting a PDRCH (physical device-to-reader channel) in response to the PRDCH, wherein the PDRCH is transmitted at a time after a first interval from the time when the reception of the PRDCH is completed, and the first interval may be determined based on a first offset determined based on the chip length of the PDRCH.

[0013] In addition, the chip length of the above PDRCH can be determined based on the SFS (small frequency shift) factor.

[0014] Additionally, the above SFS factor may be the smallest value among the available SFS factors for the device.

[0015] Additionally, the first offset is determined based on N times the chip length of the PDRCH, and N may be an integer.

[0016] In addition, if there are multiple PDRCHs, the first interval is determined by additionally considering a second offset, the second offset is determined based on K times the chip length of the PRDCH, and N and K may be different from each other.

[0017] In addition, the first interval can be determined by additionally considering the length of the PDRCH.

[0018] In addition, the above wireless communication system may be an A-IoT (ambient-internet of things) system.

[0019] Additionally, the above PRDCH may be a paging message for a random access procedure.

[0020] The purpose of this specification is to provide a method for transmitting a signal in a wireless communication system.

[0021] Figure 1 shows an example of a wireless frame structure used in a wireless communication system.

[0022] Figure 2 shows an example of a downlink (DL) / uplink (UL) slot structure in a wireless communication system.

[0023] Figure 3 is a diagram illustrating a physical channel used in a 3GPP system and a general signal transmission method using said physical channel.

[0024] Figure 4 illustrates an SS / PBCH block for initial cell connection in a 3GPP NR system.

[0025] Figure 5 illustrates a procedure for transmitting control information and control channels in a 3GPP NR system.

[0026] Figure 6 is a diagram showing a CORESET (control resource set) through which a PDCCH (physical downlink control channel) can be transmitted in a 3GPP NR system.

[0027] Figure 7 is a diagram illustrating a method for setting up a PDCCH search space in a 3GPP NR system.

[0028] Figure 8 is a conceptual diagram explaining carrier aggregation.

[0029] Figure 9 is a diagram illustrating single-carrier communication and multi-carrier communication.

[0030] Figure 10 is a diagram illustrating an example where a cross-carrier scheduling technique is applied.

[0031] FIG. 11 is a diagram showing the configuration of a terminal and a base station according to one embodiment of the present specification.

[0032] FIG. 12 is a diagram showing the topology of an Ambient IoT (Internet of Everything) according to one embodiment of the present invention.

[0033] FIG. 13 is a diagram illustrating a random access operation in an A-IoT system according to one embodiment of the present specification.

[0034] FIG. 14 is a diagram illustrating the process of generating information of PRDCH according to one embodiment of the present specification.

[0035] FIG. 15 is a diagram illustrating the process of generating information of PDRCH according to one embodiment of the present specification.

[0036] FIG. 16 is a drawing showing line coding according to one embodiment of the present specification.

[0037] FIG. 17 is a diagram showing a Miller code among line coding methods according to one embodiment of the present specification.

[0038] FIG. 18 is a diagram illustrating the inventory process of an A-IoT system according to one embodiment of the present specification.

[0039] FIG. 19 is a diagram illustrating multiple access to Msg-1 in an inventory process according to one embodiment of the present specification.

[0040] FIG. 20 is a diagram showing the resource allocation of PDRCH transmitted by a device to a reader in an A-IoT system according to one embodiment of the present specification.

[0041] FIG. 21 shows the resource allocation of PDRCH transmitted by a device to a reader in an A-IoT system according to one embodiment of the present specification.

[0042] FIG. 22 is a diagram illustrating a method for allocating frequency / time domain resources by considering a plurality of time slots according to one embodiment of the present specification.

[0043] FIG. 23 is a diagram illustrating a method for transmitting PRDCH / PDRCH considering a plurality of frequency / time domain resource allocation methods according to one embodiment of the present specification.

[0044] FIGS. 24 and 25 illustrate a method for transmitting PRDCH / PDRCH considering a time gap in a plurality of frequency / time domain resource allocations according to one embodiment of the present specification.

[0045] FIG. 26 is a diagram showing the transmission relationship of a plurality of PRDCHs in a plurality of frequency / time domain resource allocation methods considering a time gap according to one embodiment of the present specification.

[0046] FIG. 27 is a diagram showing the time relationship for the transmission of a plurality of Msg-1s and the transmission of a plurality of Msg-2s according to one embodiment of the present specification.

[0047] FIG. 28 is a diagram showing the time relationship between a plurality of Msg-1 transmissions and a single Msg-2 transmission according to one embodiment of the present specification.

[0048] FIG. 29 is a diagram showing the transmission relationship of Msg-1 using a plurality of frequency domain resources according to one embodiment of the present specification.

[0049] FIG. 30 is a diagram showing an FDM method for Msg-1 according to one embodiment of the present specification.

[0050] FIG. 31 is a diagram showing the transmission relationship of Msg-1, Msg-2, and Msg-3 according to one embodiment of the present invention.

[0051] FIG. 32 is a diagram illustrating the transmission of Msg-2 in a time domain resource as a partial response to Msg-1 according to one embodiment of the present specification.

[0052] FIG. 33 is a diagram illustrating a frequency domain multiplexing method using different BLFs according to one embodiment of the present specification.

[0053] FIG. 34 is a diagram showing a time-domain resource allocation structure for transmitting PDRCH according to one embodiment of the present specification.

[0054] FIG. 35 shows an allocation structure of time domain resources for transmitting PDRCH according to one embodiment of the present specification.

[0055] FIG. 36 is a diagram of another embodiment showing a time-domain resource allocation structure for transmitting PDRCH according to one embodiment of the present specification.

[0056] FIG. 37 is a diagram illustrating a method for allocating a plurality of time domain resources and a plurality of frequency domain resources according to one embodiment of the present specification.

[0057] FIG. 38 is a diagram illustrating a method in which a plurality of time domain resources and a plurality of frequency domain resources are adaptively allocated according to one embodiment of the present specification.

[0058] FIG. 39 is a diagram showing the relationship between DSB and SSB in frequency domain resource allocation according to one embodiment of the present specification.

[0059] FIG. 40 is a diagram illustrating a method for allocating frequency domain resources according to one embodiment of the present specification.

[0060] FIG. 41 is a diagram showing the structure of a preamble preceding a PRDCH according to one embodiment of the present specification.

[0061] FIG. 42 is a diagram showing the time relationship for message transmission within an inventory process according to one embodiment of the present specification.

[0062] FIG. 43 is a diagram illustrating a method for setting a time domain variable based on whether a time counting function exists in a device according to one embodiment of the present specification.

[0063] FIG. 44 is a diagram illustrating a method of configuring FDMA by transmission bandwidth using SFS according to one embodiment of the present specification.

[0064] FIG. 45 is a diagram showing the time relationship for a device to monitor Msg2 according to one embodiment of the present specification.

[0065] FIG. 46 is a diagram showing the start time of monitoring of individual Msg2 among the time relationships for monitoring Msg2 according to one embodiment of the present specification.

[0066] FIG. 47 is a diagram showing the individual start time of Msg2 monitoring among the time relationships for Msg2 monitoring according to one embodiment of the present specification.

[0067] FIG. 48 is a diagram showing the common start time of Msg2 monitoring among the time relationships for Msg2 monitoring according to one embodiment of the present specification.

[0068] FIG. 49 is a diagram showing a common start time for Msg2 monitoring including a plurality of responses among the time relationships for monitoring Msg2 of a device according to one embodiment of the present specification.

[0069] FIG. 50 is a diagram showing the relationship between the start time of Msg2 monitoring, the paging message, and the R2D trigger message among the time relationships for Msg2 monitoring according to one embodiment of the present specification.

[0070] FIG. 51 is a diagram showing a time point based on the transmission of Msg2 and Msg3 among the time relationships for monitoring Msg2 according to one embodiment of the present specification.

[0071] FIGS. 52 and 53 are drawings illustrating an FDMA method considering SFS according to one embodiment of the present specification.

[0072] Figure 54 is a diagram illustrating a method for matching the same data rate from different frequency resources in an FDMA situation.

[0073] FIG. 55 is a diagram illustrating multiplexing and multiple access methods in the transmission of Msg 1 according to one embodiment of the present specification.

[0074] FIG. 56 is a diagram showing the transmission method of Msg2 and Msg3 according to one embodiment of the present specification.

[0075] FIG. 57 illustrates a method for transmitting Msg2 and Msg3 according to one embodiment of the present specification.

[0076] FIG. 58 is a diagram showing the transmission relationship of individual Msg2 in a time domain resource and Msg3 in a frequency and time resource according to one embodiment of the present specification.

[0077] Figure 59 is a diagram showing the case where there is only one time resource in which Msg1 can be transmitted.

[0078] FIG. 60 is a diagram showing the transmission relationship when there are two time resources for Msg1 according to one embodiment of the present specification.

[0079] FIG. 61 is a diagram showing the relationship with Msg2 transmission when Msg1 according to one embodiment of the present specification can be transmitted using a plurality of time and frequency resources.

[0080] FIG. 62 is a diagram illustrating the transmission of a Nack message for Msg3 according to one embodiment of the present specification.

[0081] FIG. 63 is a diagram showing the relationship between CBRA (contention-based random access) and CFRA (contention-free random access) according to one embodiment of the present invention.

[0082] FIG. 64 illustrates a method for performing wireless communication according to one embodiment of the present specification.

[0083] The terms used in this specification have been selected to be as widely used as possible, taking into account their functions in the present invention; however, these may vary depending on the intent, convention, or emergence of new technologies of those skilled in the art. In addition, in certain cases, terms have been arbitrarily selected by the applicant, and in such cases, their meanings will be described in the relevant description of the invention. Therefore, it should be noted that the terms used in this specification should be interpreted based on their actual meanings and the overall content of this specification, rather than merely their names.

[0084] Throughout the specification, when a configuration is described as being "connected" to another configuration, this includes not only cases where they are "directly connected" but also cases where they are "electrically connected" with other components interposed between them. Furthermore, when a configuration is described as "including" a specific component, this means that, unless specifically stated otherwise, it does not exclude other components but may include additional components. In addition, the limitation "greater than or equal to" or "less than or equal to" based on a specific threshold value may be appropriately replaced with "greater than" or "less than," respectively, depending on the embodiment.

[0085] The following technologies can be used in various wireless access systems such as CDMA (code division multiple access), FDMA (frequency division multiple access), TDMA (time division multiple access), OFDMA (orthogonal frequency division multiple access), and SC-FDMA (single carrier frequency division multiple access). CDMA can be implemented using radio technologies such as UTRA (Universal Terrestrial Radio Access) or CDMA2000. TDMA can be implemented using radio technologies such as GSM (Global System for Mobile Communications), GPRS (General Packet Radio Service), and EDGE (Enhanced Data Rates for GSM Evolution). OFDMA can be implemented using radio technologies such as IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802-20, and E-UTRA (Evolved UTRA). UTRA is part of the UMTS (Universal Mobile Telecommunications System). 3GPP (3rd Generation Partnership Project) LTE (long term evolution) is part of E-UMTS (Evolved UMTS) using E-UTRA, and LTE-A (Advanced) is an evolved version of 3GPP LTE.3GPP NR (New Radio) is a system designed separately from LTE / LTE-A to support eMBB (enhanced Mobile BroadBand), URLLC (Ultra-Reliable and Low Latency Communication), and mMTC (massive Machine Type Communication) services, which are requirements of IMT-2020. For clarity, the description focuses on 3GPP NR, but the technical concept of the present invention is not limited thereto.

[0086] In various embodiments of this specification, " / " and "," shall be interpreted as indicating "and / or". For example, "A / B" may mean "A and / or B". Furthermore, "A, B" may mean "A and / or B". Furthermore, "A / B / C" may mean "at least one of A, B and / or C". Furthermore, "A, B, C" may mean "at least one of A, B and / or C".

[0087] Furthermore, in various embodiments of this specification, "or" should be interpreted as indicating "and / or". For example, "A or B" may include "only A", "only B", and / or "both A and B". In other words, in various embodiments of this specification, "or" should be interpreted as indicating "additionally or alternatively".

[0088] Unless otherwise specified in this specification, a base station may include a gNB (next generation node B) as defined in 3GPP NR. Additionally, unless otherwise specified, a terminal may include UE (user equipment). Hereinafter, to aid in understanding the description, each content is described separately as an example, but each example may be used in combination with one another. In this disclosure, the configuration of a terminal may refer to a configuration by a base station. Specifically, the base station may transmit a channel or signal to the terminal to set the value of a parameter used in the operation of the terminal or in a wireless communication system.

[0089] Figure 1 shows an example of a wireless frame structure used in a wireless communication system.

[0090] Referring to Fig. 1, the radio frame (or radio frame) used in a 3GPP NR system is 10ms (Δf max N f / 100) * T c It can have a length of ). In addition, the wireless frame consists of 10 subframes (SF) of equal size. Here, Δf max =480*10 3 Hz, N f =4096, T c =1 / (Δf ref *N f,ref ), Δf ref =15*10 3 Hz, N f,ref = 2048. Ten subframes within a single radio frame can each be numbered from 0 to 9. Each subframe has a length of 1ms and can consist of one or more slots depending on the subcarrier spacing. More specifically, the available subcarrier spacing in 3GPP NR systems is 15*2 μIt is kHz. μ is the subcarrier spacing configuration, and μ can have values ​​from 0 to 4. That is, 15kHz, 30kHz, 60kHz, 120kHz, or 240kHz can be used as the subcarrier spacing. A 1ms subframe is 2 μ It can be composed of slots. In this case, the length of each slot is 2 -μ It is ms. 2 within one subframe μ The slots are each from 0 to 2 μ Numbers from 0 to 1 can be assigned. Additionally, the slots within a single wireless frame can be assigned from 0 to 10*2 respectively. μ - Numbers up to 1 may be assigned. Time resources may be distinguished by at least one of a wireless frame number (also called a wireless frame index), a subframe number (also called a subframe index), and a slot number (or slot index).

[0091] FIG. 2 shows an example of a downlink (DL) / uplink (UL) slot structure in a wireless communication system. In particular, FIG. 2 shows the structure of a resource grid in a 3GPP NR system.

[0092] There is one resource grid per antenna port. Referring to FIG. 2, a slot contains multiple orthogonal frequency division multiplexing (OFDM) symbols in the time domain and multiple resource blocks (RBs) in the frequency domain. An OFDM symbol also refers to a single symbol interval. Unless otherwise noted, an OFDM symbol may simply be referred to as a symbol. One RB contains 12 consecutive subcarriers in the frequency domain. Referring to FIG. 2, the signal transmitted in each slot is N size,μ grid,x * N RB scN subcarriers and N slot symb It can be represented as a resource grid composed of OFDM symbols. Here, x=DL for the downlink resource grid and x=UL for the uplink resource grid. N size,μ grid,x represents the number of resource blocks (RB) according to the subcarrier spacing factor μ (where x is DL or UL), and N slot symb represents the number of OFDM symbols in the slot. N RB sc is the number of subcarriers constituting a single RB, N RB sc = 12. Depending on the multiple access method, OFDM symbols can be referred to as CP-OFDM (cyclic prefix OFDM) symbols or DFT-S-OFDM (discrete Fourier transform spread OFDM) symbols.

[0093] The number of OFDM symbols included in a single slot may vary depending on the length of the cyclic prefix (CP). For example, in the case of a normal CP, a single slot may contain 14 OFDM symbols, whereas in the case of an extended CP, a single slot may contain 12 OFDM symbols. In a specific embodiment, the extended CP may be used only at a 60 kHz subcarrier interval. Although FIG. 2 illustrates a case where a single slot consists of 14 OFDM symbols for convenience of explanation, embodiments of the present invention can be applied in the same manner to slots having a different number of OFDM symbols. Referring to FIG. 2, each OFDM symbol is, in the frequency domain, N size,μ grid,x * N RB scIt includes several subcarriers. The types of subcarriers can be divided into data subcarriers for data transmission, reference signal subcarriers for the transmission of reference signals, and guard bands. The carrier frequency is also called the center frequency (fc).

[0094] One RB is N in the frequency domain RB sc It can be defined by (e.g., 12) consecutive subcarriers. For reference, a resource consisting of one OFDM symbol and one subcarrier can be referred to as a resource element (RE) or tone. Therefore, one RB is N slot symb * N RB sc It can be composed of resource elements. Each resource element within the resource grid can be uniquely defined by an index pair (k, l) within a single slot. k ranges from 0 to N in the frequency domain. size,μ grid, x * N RB sc It is an index assigned up to 1, where l ranges from 0 to N in the time domain. slot symb - It can be an index assigned up to 1.

[0095] In order for a terminal to receive a signal from a base station or transmit a signal to a base station, the terminal's time / frequency synchronization may need to be aligned with the base station's time / frequency synchronization. This is because only when the base station and the terminal are synchronized can the terminal determine the time and frequency parameters necessary to perform the demodulation of the DL signal and the transmission of the UL signal at the correct time.

[0096] Each symbol of a radio frame operating in TDD (time division duplex) or unpaired spectrum may consist of at least one of a downlink symbol (DL symbol), an uplink symbol (UL symbol), or a flexible symbol. In FDD (frequency division duplex) or paired spectrum, a radio frame operating as a downlink carrier may consist of a downlink symbol or a flexible symbol, and a radio frame operating as an uplink carrier may consist of an uplink symbol or a flexible symbol. Downlink transmission is possible with a downlink symbol but not with an uplink symbol, and uplink transmission is possible with an uplink symbol but not with a downlink symbol. Whether a flexible symbol is used for downlink or uplink transmission may be determined based on the signal.

[0097] Information regarding the type of each symbol, that is, information indicating one of downlink symbols, uplink symbols, and flexible symbols, may be composed of a cell-specific (or common) radio resource control (RRC) signal. Additionally, information regarding the type of each symbol may be further composed of a terminal-specific (or dedicated) RRC signal. The base station uses the cell-specific RRC signal to provide i) the period of the cell-specific slot configuration, ii) the number of slots containing only downlink symbols from the beginning of the cell-specific slot configuration period, iii) the number of downlink symbols from the first symbol of the slot immediately following the slot containing only downlink symbols, iv) the number of slots containing only uplink symbols from the end of the cell-specific slot configuration period, and v) the number of uplink symbols from the last symbol of the slot immediately preceding the slot containing only uplink symbols. Here, a symbol that is not composed of either uplink symbols or downlink symbols is a flexible symbol.

[0098] When information regarding the symbol type is configured as a terminal-specific RRC signal, the base station can signal whether the flexible symbol is a downlink symbol or an uplink symbol using a cell-specific RRC signal. In this case, the terminal-specific RRC signal cannot change the downlink symbol or uplink symbol configured by the cell-specific RRC signal to another symbol type. The terminal-specific RRC signal is for each slot, N of the corresponding slot slot symb Number of downlink symbols among the symbols, N of the corresponding slot slot symbThe number of uplink symbols among the symbols can be signaled. In this case, the downlink symbols of the slot can be configured consecutively from the first symbol to the i-th symbol of the slot. Additionally, the uplink symbols of the slot can be configured consecutively from the j-th symbol to the last symbol of the slot (where i <j). 슬롯에서 상향링크 심볼과 하향링크 심볼 어느 것으로도 구성되지 않은 심볼은 플랙서블 심볼이다.

[0099] As another method of providing slot format information to a terminal, the terminal can receive a slot format indicator (SFI), which is information about the symbol type included in DCI format 2_0 transmitted via GC (group common)-PDCCH. Here, GC-PDCCH can be CRC scrambled into SFI-RNTI for terminals receiving slot configuration information. In the following, the SFI received via GC-PDCCH may be referred to as dynamic SFI.

[0100] The terminal can receive a dynamic SFI via GC-PDCCH and be indicated that a cell-specific flexible symbol or a terminal-specific flexible symbol is one of a downlink symbol, an uplink symbol, or a flexible symbol. In other words, only the flexible symbol semi-statically configured to the terminal can be indicated as one of a downlink symbol, an uplink symbol, or a flexible symbol via the dynamic SFI, and the semi-statically configured downlink symbol or uplink symbol cannot be expected to be indicated as a different type of symbol by the dynamic SFI. To receive a PDCCH containing a DCI format 2_0 containing a dynamic SFI, the terminal can perform blind decoding at every monitoring cycle configured by the base station. If the terminal succeeds in receiving the PDCCH by performing blind decoding, the terminal can apply the slot configuration information indicated by the dynamic SFI starting from the slot in which the PDCCH was received.

[0101] The terminal may receive from the base station a slot format combination that can be specified in dynamic SFI. The slot format combination may specify the slot format for each slot for 1 to 256 slots, and the terminal may receive from the base station multiple slot format combinations configured, and one of the slot format combination indices may be specified through dynamic SFI. The slot format configured for each slot may be as defined in Table 1 in 3GPP TS38.213 v16.8.0.

[0102]

[0103] In Table 1, D represents the downlink symbol, U represents the uplink symbol, and F represents the flexible symbol. As shown in Table 1, up to two DL / UL switching operations may be allowed within one slot.

[0104] When a terminal is configured or instructed to set a slot format in TDD or unpaired spectrum, allocating limited time domain resources as uplink resources can result in reduced uplink coverage, increased latency, and reduced capacity. To address this, specific time domain resources within a cell may be used for both downlink reception and uplink transmission. Here, even if the base station uses specific time domain resources for both downlink reception and uplink transmission, the terminal may only support half-duplex communication, allowing only one operation—either downlink reception or uplink transmission—within the same time domain resources.

[0105] The specific time domain resource mentioned above may be a cell-specific flexible symbol among the semi-statically configured slot formats described above. This is because, when a cell uses a specific time domain resource for both downlink reception and uplink transmission, in order to minimize inter-UE interference caused by transmission and reception in different symbol types (DL / UL or UL / DL), at least the cell-specific downlink symbol or the cell-specific uplink symbol may not be considered, and only the cell-specific flexible symbol may be considered.

[0106] FIG. 3 is a diagram illustrating a physical channel used in a 3GPP system (e.g., NR) and a general signal transmission method using said physical channel.

[0107] When the terminal's power is turned on or the terminal newly enters a cell, the terminal performs an initial cell search operation (S101). Specifically, the terminal can synchronize with the base station during the initial cell search. To this end, the terminal receives a primary synchronization signal (PSS) and a secondary synchronization signal (SSS) from the base station to synchronize with the base station and obtain information such as a cell ID. Afterward, the terminal receives a physical broadcast channel from the base station to obtain broadcast information within the cell.

[0108] A terminal that has completed initial cell search can obtain more specific system information than the system information obtained through initial cell search by receiving a physical downlink control channel (PDCCH) and a physical downlink shared channel (PDSCH) according to the information carried in the PDCCH (S102). Here, the system information received by the terminal is cell-common system information for the terminal to operate correctly at the physical layer in the Radio Resource Control (RRC), and is referred to as remaining system information or system information block (SIB) 1.

[0109] When the terminal first connects to the base station or when there are no wireless resources available for signal transmission (when the terminal is in RRC_IDLE mode), the terminal may perform a random access process with respect to the base station (steps S103 to S106). First, the terminal transmits a preamble through a physical random access channel (PRACH) (S103), and may receive a response message for the preamble from the base station through a PDCCH and a corresponding PDSCH (S104). If a valid random access response message is received by the terminal, the terminal transmits data including its identifier, etc., to the base station through a physical uplink shared channel (PUSCH) as instructed by an uplink grant transmitted from the base station via the PDCCH (S105). Next, the terminal waits for the reception of a PDCCH as instructed by the base station to resolve collisions. If the terminal successfully receives a PDCCH with its identifier (S106), the random access process is terminated. During the random access process, the terminal can obtain terminal-specific system information from the RRC layer that is necessary for the terminal to operate correctly at the physical layer. When the terminal obtains terminal-specific system information from the RRC layer, the terminal enters RRC connected mode.

[0110] The RRC layer is used for generating and managing messages for control between a terminal and a Radio Access Network (RAN). More specifically, the base station and the terminal can perform broadcasting of cell system information required by all terminals within the cell, management of paging message delivery, mobility management and handover, terminal measurement reporting and control thereof, terminal capability management, and storage management including device management at the RRC layer. Generally, since the update of a signal transmitted at the RRC layer (hereinafter referred to as an RRC signal) is longer than the transmission time interval (TTI) at the physical layer, the RRC signal can be maintained without changing for a long period.

[0111] After the procedure described above, the terminal can perform PDCCH / PDSCH reception (S107) and transmission of the physical uplink shared channel (PUSCH) / physical uplink control channel (PUCCH) (S108) as a general uplink / downlink signal transmission procedure. In particular, the terminal can receive downlink control information (DCI) through the PDCCH. The DCI may include control information such as resource allocation information for the terminal. Additionally, the format of the DCI may vary depending on the purpose of use. The uplink control information (UCI) transmitted by the terminal to the base station via the uplink may include downlink / uplink ACK / NACK signals, CQI (channel quality indicator), PMI (precoding matrix index), RI (rank indicator), etc. Here, CQI, PMI, and RI may be included in CSI (channel state information). In the case of a 3GPP NR system, the terminal can transmit control information such as the aforementioned HARQ-ACK and CSI through PUSCH and / or PUCCH.

[0112] Figure 4 illustrates an SS / PBCH block for initial cell connection in a 3GPP NR system.

[0113] When the terminal is powered on or intends to connect to a new cell, it can acquire time and frequency synchronization with the cell and perform an initial cell search process. During the cell search process, the terminal obtains the cell's physical cell identity N cell IDIt can detect [this]. To do this, the terminal can synchronize with the base station by receiving synchronization signals, for example, a main synchronization signal (PSS) and a secondary synchronization signal (SSS), from the base station. At this time, the terminal can obtain information such as a cell identifier (identity, ID).

[0114] Referring to FIG. 4(a), the synchronization signal (SS) is described in more detail. The synchronization signal can be divided into PSS and SSS. PSS can be used to obtain time-domain synchronization and / or frequency-domain synchronization, such as OFDM symbol synchronization and slot synchronization. SSS can be used to obtain frame synchronization and cell group ID. Referring to FIG. 4(a) and Table 2, the SS / PBCH block can be composed of 20 RBs (= 240 subcarriers) consecutive in the frequency axis and 4 OFDM symbols consecutive in the time axis. In this case, within the SS / PBCH block, the PSS is transmitted through the 56th to 182nd subcarriers in the first OFDM symbol, and the SSS is transmitted through the 56th to 182nd subcarriers in the third OFDM symbol. Here, the lowest subcarrier index of the SS / PBCH block is assigned starting from 0. In the first OFDM symbol where the PSS is transmitted, the base station does not transmit signals through the remaining subcarriers, namely subcarriers 0 through 55 and 183 through 239. Also, in the third OFDM symbol where the SSS is transmitted, the base station does not transmit signals through subcarriers 48 through 55 and 183 through 191. In the SS / PBCH block, the base station transmits the PBCH (physical broadcast channel) through the remaining REs excluding the above signals.

[0115]

[0116] The SS can be grouped into a total of 1,008 unique physical layer cell IDs through a combination of three PSSs and SSSs, specifically into 336 physical layer cell identifier groups, each containing three unique identifiers, such that each physical layer cell ID is part of only one physical layer cell identifier group. Therefore, physical layer cell ID N cell ID = 3N (1) ID + N (2) ID is an index N within the range of 0 to 335 representing a physical-layer cell-identifier group. (1) ID and an index N from 0 to 2 representing the physical-layer identifier within the physical-layer cell-identifier group. (2) ID It can be uniquely defined by. The terminal can detect the PSS to identify one of three unique physical-layer identifiers. Additionally, the terminal can detect the SSS to identify one of 336 physical-layer cell IDs associated with the physical-layer identifier. In this case, the sequence d of the PSS PSS (n) is as follows.

[0117]

[0118] Here, And,

[0119] It is given as.

[0120] Also, the sequence d of the SSS SSS (n) is as follows.

[0121]

[0122] Here, And,

[0123] It is given as.

[0124] A wireless frame of 10 ms length can be divided into two half frames of 5 ms length. Referring to FIG. 4(b), the slot in which the SS / PBCH block is transmitted within each half frame is described. The slot in which the SS / PBCH block is transmitted can be any one of cases A, B, C, D, or E. In case A, the subcarrier interval is 15 kHz, and the start time of the SS / PBCH block is {2, 8} + 14*n-th symbol. At this time, n can be 0 or 1 at a carrier frequency of 3 GHz or less. Also, at a carrier frequency between 3 GHz and 6 GHz or less, n can be 0, 1, 2, or 3. In case B, the subcarrier interval is 30 kHz, and the start time of the SS / PBCH block is {4, 8, 16, 20} + 28*n-th symbol. At this time, n can be 0 at a carrier frequency of 3 GHz or less. Additionally, at carrier frequencies greater than 3 GHz and less than or equal to 6 GHz, n can be 0 or 1. In case C, the subcarrier interval is 30 kHz, and the start time of the SS / PBCH block is {2, 8} + 14*n-th symbol. At this time, at carrier frequencies less than or equal to 3 GHz, n can be 0 or 1. Additionally, at carrier frequencies greater than 3 GHz and less than or equal to 6 GHz, n can be 0, 1, 2, or 3. In case D, the subcarrier interval is 120 kHz, and the start time of the SS / PBCH block is {4, 8, 16, 20} + 28*n-th symbol. At this time, at carrier frequencies greater than or equal to 6 GHz, n can be 0, 1, 2, 3, 5, 6, 7, 8, 10, 11, 12, 13, 15, 16, 17, or 18. In case E, the subcarrier interval is 240 kHz, and the start time of the SS / PBCH block is {8, 12, 16, 20, 32, 36, 40, 44} + 56*n-th symbol. At this time, at a carrier frequency of 6 GHz or higher, n can be 0, 1, 2, 3, 5, 6, 7, 8.

[0125] FIG. 5 illustrates a procedure for transmitting control information and control channels in a 3GPP NR system. Referring to FIG. 5(a), a base station may add a cyclic redundancy check (CRC) masked (e.g., XOR operation) with a radio network temporary identifier (RNTI) to control information (e.g., downlink control information, DCI) (S202). The base station may scramble the CRC with an RNTI value determined according to the purpose / target of each control information. A common RNTI used by one or more terminals may include at least one of SI-RNTI (system information RNTI), P-RNTI (paging RNTI), RA-RNTI (random access RNTI), and TPC-RNTI (transmit power control RNTI). Additionally, a terminal-specific RNTI may include at least one of C-RNTI (cell temporary RNTI) and CS-RNTI. Subsequently, the base station can perform rate-matching according to the amount of resource(s) used for PDCCH transmission after performing channel encoding (e.g., polar coding) (S204) (S206). Subsequently, the base station can multiplex DCI(s) based on a CCE (control channel element)-based PDCCH structure (S208). In addition, the base station can apply additional processes (S210), such as scrambling, modulation (e.g., QPSK), and interleaving, to the multiplexed DCI(s) and then map them to the resources to be transmitted. A CCE is a basic resource unit for PDCCH, and one CCE can be composed of multiple (e.g., 6) REGs (resource element groups). One REG can be composed of multiple (e.g., 12) REs.The number of CCEs used for a single PDCCH can be defined as the aggregation level. In 3GPP NR systems, 1, 2, 4, 8, or 16 aggregation levels can be used. FIG. 5(b) is a diagram regarding CCE aggregation levels and PDCCH multiplexing, showing the types of CCE aggregation levels used for a single PDCCH and the CCE(s) transmitted in the control area accordingly.

[0126] Figure 6 is a diagram showing a CORESET (control resource set) in which a PDCCH (physical downlink control channel) can be transmitted in a 3GPP NR system.

[0127] A CORESET is a time-frequency resource through which a PDCCH, a control signal for a terminal, is transmitted. Additionally, the search space described below can be mapped to a single CORESET. Therefore, instead of monitoring all frequency bands to receive a PDCCH, the terminal can decode the PDCCH mapped to the CORESET by monitoring the time-frequency area designated as the CORESET. The base station can configure one or multiple CORESETs per cell for the terminal. A CORESET can be composed of up to three consecutive symbols along the time axis. Additionally, a CORESET can be composed of six consecutive PRBs along the frequency axis. In the embodiment of FIG. 5, CORESET#1 is composed of consecutive PRBs, while CORESET#2 and CORESET#3 are composed of discontinuous PRBs. A CORESET can be located in any symbol within a slot. For example, in the embodiment of FIG. 5, CORESET#1 starts at the first symbol of the slot, CORESET#2 starts at the 5th symbol of the slot, and CORESET#9 starts at the 9th symbol of the slot.

[0128] Figure 7 is a diagram illustrating a method for setting up a PDCCH search space in a 3GPP NR system.

[0129] In order to transmit a PDCCH to a terminal, each CORESET may have at least one search space. In an embodiment of the present invention, the search space is a set of all time-frequency resources (hereinafter referred to as PDCCH candidates) where the terminal's PDCCH can be transmitted. The search space may include a common search space that 3GPP NR terminals must search in common, and a terminal-specific or UE-specific search space that a specific terminal must search. In the common search space, PDCCHs configured to be searched in common by all terminals in a cell belonging to the same base station can be monitored. Additionally, the terminal-specific search space may be configured per terminal so that PDCCHs assigned to each terminal can be monitored at different search space locations depending on the terminal. In the case of a terminal-specific search space, search spaces between terminals may partially overlap due to the limited control area where PDCCHs can be assigned. Monitoring a PDCCH includes blind decoding PDCCH candidates within the search space. When blind decoding is successful, it can be expressed that PDCCH is (successfully) detected / received, and when blind decoding fails, it can be expressed that PDCCH is not detected / received or is not successfully detected / received.

[0130] For convenience of explanation, a PDCCH scrambled with a group common (GC) RNTI already known to one or more terminals to transmit downlink control information to one or more terminals is referred to as a group common (GC) PDCCH or a common PDCCH. Additionally, a PDCCH scrambled with a terminal-specific RNTI already known to a specific terminal to transmit uplink scheduling information or downlink scheduling information to one specific terminal is referred to as a terminal-specific PDCCH. The common PDCCH may be included in a common search space, and the terminal-specific PDCCH may be included in a common search space or a terminal-specific PDCCH.

[0131] The base station can notify each terminal or group of terminals via PDCCH of information related to resource allocation for the transmission channels PCH (paging channel) and DL-SCH (downlink-shared channel) (i.e., DL Grant) or information related to resource allocation for UL-SCH (uplink-shared channel) and HARQ (hybrid automatic repeat request) (i.e., UL Grant). The base station can transmit PCH transmission blocks and DL-SCH transmission blocks via PDSCH. The base station can transmit data excluding specific control information or specific service data via PDSCH. Additionally, the terminal can receive data excluding specific control information or specific service data via PDSCH.

[0132] A base station may transmit PDSCH data by including information in the PDCCH regarding which terminal (one or more terminals) the data is being transmitted to and how the terminal should receive and decode the PDSCH data. For example, assume that a DCI transmitted through a specific PDCCH is CRC-masked with an RNTI named "A," that the DCI indicates that the PDSCH is allocated to a radio resource named "B" (e.g., frequency location), and indicates transmission format information named "C" (e.g., transmission block size, modulation method, coding information, etc.). The terminal monitors the PDCCH using the RNTI information it possesses. In this case, if there is a terminal that blind-decodes the PDCCH using the "A" RNTI, that terminal receives the PDCCH and, through the information in the received PDCCH, receives the PDSCH indicated by "B" and "C".

[0133] Table 3 shows an example of a PUCCH (physical uplink control channel) used in a wireless communication system.

[0134]

[0135] PUCCH can be used to transmit the following uplink control information (UCI).

[0136] - SR (Scheduling Request): Information used to request uplink UL-SCH resources.

[0137] - HARQ-ACK: A response to a PDCCH (indicating a DL SPS release) and / or a response to a downlink transport block (TB) on the PDSCH. HARQ-ACK indicates the successful reception of information transmitted via the PDCCH or PDSCH. HARQ-ACK responses include a positive ACK (simply ACK), a negative ACK (hereinafter NACK), a DTX (Discontinuous Transmission), or a NACK / DTX. Here, the term HARQ-ACK is used interchangeably with HARQ-ACK / NACK and ACK / NACK. Generally, ACK is represented by a bit value of 1 and NACK can be represented by a bit value of 0.

[0138] - CSI (Channel State Information): This is feedback information regarding the downlink channel. It is generated by the terminal based on the CSI-RS (Reference Signal) transmitted by the base station. MIMO (Multiple Input Multiple Output) related feedback information includes RI (Rank Indicator) and PMI (Precoding Matrix Indicator). CSI can be divided into CSI Part 1 and CSI Part 2 depending on the information represented by the CSI.

[0139] In 3GPP NR systems, five PUCCH formats can be used to support various service scenarios, various channel environments, and frame structures.

[0140] PUCCH Format 0 is a format capable of transmitting 1-bit or 2-bit HARQ-ACK information or SR. PUCCH Format 0 can be transmitted via one or two OFDM symbols in the time axis and one PRB in the frequency axis. When PUCCH Format 0 is transmitted via two OFDM symbols, the same sequence can be transmitted via different RBs for both symbols. In this case, the sequence may be a sequence cyclically shifted (CS) from the base sequence used in PUCCH Format 0. Through this, the terminal can obtain frequency diversity gain. Specifically, the terminal M bit Bit UCI (M bit Cyclic shift (CS) value m depending on = 1 or 2) cs It can determine. In addition, a base sequence of length 12 with a fixed CS value m cs Based on this, a cyclically shifted sequence can be transmitted by mapping it to 12 REs of 1 OFDM symbol and 1 RB. The number of cyclic shifts available to the terminal is 12, and M bit When = 1, 1-bit UCI 0 and 1 can each be mapped to two cyclically shifted sequences with a difference of 6 in their cyclic shift values. Also, M bit In the case where = 2, 2-bit UCI 00, 01, 11, 10 can each be mapped to four cyclically shifted sequences with a difference of 3 in the cyclic shift values.

[0141] PUCCH Format 1 can transmit 1-bit or 2-bit HARQ-ACK information or SR. PUCCH Format 1 can be transmitted via consecutive OFDM symbols in the time axis and a single PRB in the frequency axis. Here, the number of OFDM symbols occupied by PUCCH Format 1 can be one of 4 to 14. More specifically, M bit= A single UCI can be modulated with BPSK. The terminal is M bit A UCI with =2 can be modulated using QPSK (quadrature phase shift keying). A signal is obtained by multiplying the modulated complex valued symbol d(0) by a sequence of length 12. In this case, the sequence may be the base sequence used in PUCCH format 0. The terminal transmits the obtained signal by spreading it as a time-axis orthogonal cover code (OCC) onto the even-numbered OFDM symbols assigned to PUCCH format 1. In PUCCH format 1, the maximum number of different terminals multiplexed to the same RB is determined by the length of the OCC used. A demodulation reference signal (DMRS) can be spread as an OCC and mapped to the odd-numbered OFDM symbols of PUCCH format 1.

[0142] PUCCH Format 2 can transmit UCIs exceeding 2 bits. PUCCH Format 2 can be transmitted via one or two OFDM symbols in the time axis and one or multiple RBs in the frequency axis. When PUCCH Format 2 is transmitted via two OFDM symbols, the same sequence can be transmitted via two OFDM symbols to different RBs. Here, the sequence consists of multiple modulated complex symbols d(0), …, d(M symbol -1) can be. Here, M symbol is M bit It can be / 2. Through this, the terminal can obtain frequency diversity gain. More specifically, M bit Bit UCI (M bit >2) is bit-level scrambled and QPSK modulated and mapped to RB(s) of one or two OFDM symbols. Here, the number of RBs can be one of 1 to 16.

[0143] PUCCH Format 3 or PUCCH Format 4 can transmit a UCI exceeding 2 bits. PUCCH Format 3 or PUCCH Format 4 can be transmitted via consecutive OFDM symbols in the time axis and a single PRB in the frequency axis. The number of OFDM symbols occupied by PUCCH Format 3 or PUCCH Format 4 can be one of 4 to 14. Specifically, the terminal is M bit Bit UCI (M bit Modulate >2) with π / 2-BPSK (Binary Phase Shift Keying) or QPSK to obtain complex number symbols d(0)~d(M symb -1) can be generated. Here, if π / 2-BPSK is used, M symb =M bit And, if you use QPSK, M symb =M bit / 2. The terminal may not apply block-unit spreading to PUCCH format 3. However, the terminal may apply block-unit spreading to one RB (i.e., 12 subcarriers) using a PreDFT-OCC of length 12 so that PUCCH format 4 can have two or four multiplexing capacities. The terminal may transmit the spread signal by transmitting precoding (or DFT-precoding) the spread signal and mapping it to each RE.

[0144] At this time, the number of RBs occupied by PUCCH format 2, PUCCH format 3, or PUCCH format 4 can be determined by the length of the UCI transmitted by the terminal and the maximum code rate. When the terminal uses PUCCH format 2, the terminal can transmit HARQ-ACK information and CSI information together through PUCCH. If the number of RBs that the terminal can transmit is greater than the maximum number of RBs available for PUCCH format 2, PUCCH format 3, or PUCCH format 4, the terminal may transmit only the remaining UCI information without transmitting some UCI information according to the priority of the UCI information.

[0145] PUCCH format 1, PUCCH format 3, or PUCCH format 4 can be configured via an RRC signal to indicate frequency hopping within a slot. When frequency hopping is configured, the index of the RB to be frequency-hopped can be configured via an RRC signal. When PUCCH format 1, PUCCH format 3, or PUCCH format 4 is transmitted over N OFDM symbols in the time axis, the first hop may have floor (N / 2) OFDM symbols and the second hop may have ceil (N / 2) OFDM symbols.

[0146] PUCCH format 1, PUCCH format 3, or PUCCH format 4 may be configured to be transmitted repeatedly across multiple slots. In this case, the number of slots K in which PUCCH is transmitted repeatedly may be configured by an RRC signal. The PUCCH transmitted repeatedly must start at the same position of the OFDM symbol within each slot and have the same length. If any of the OFDM symbols in the slot in which the terminal is to transmit the PUCCH is indicated as a DL symbol by the RRC signal, the terminal may not transmit the PUCCH in that slot but may defer transmission to the next slot.

[0147] Meanwhile, in a 3GPP NR system, a terminal can perform transmission and reception using a bandwidth that is less than or equal to the bandwidth of the carrier (or cell). To this end, the terminal may receive a bandwidth part (BWP) composed of a continuous portion of the carrier's bandwidth. A terminal operating under TDD or in unpaired spectrum may receive up to four DL / UL BWP pairs for one carrier (or cell). Additionally, the terminal may activate one DL / UL BWP pair. A terminal operating under FDD or in paired spectrum may receive up to four DL BWPs for the downlink carrier (or cell) and up to four UL BWPs for the uplink carrier (or cell). The terminal may activate one DL BWP and one UL BWP for each carrier (or cell). The terminal may not receive or transmit on time-frequency resources other than the active BWP. The active BWP may be referred to as the active BWP.

[0148] A base station may indicate the active BWP among the configured BWPs to the terminal via downlink control information (DCI). The BWP indicated via the DCI is activated, and the other configured BWP(s) are deactivated. In a carrier (or cell) operating in TDD, the base station may include a bandwidth part indicator (BPI) indicating the active BWP in the DCI that schedules the PDSCH or PUSCH to change the terminal's DL / UL BWP pair. The terminal receives the DCI that schedules the PDSCH or PUSCH and can identify the active DL / UL BWP pair based on the BPI. In the case of a downlink carrier (or cell) operating in FDD, the base station may include a BPI indicating the active BWP in the DCI that schedules the PDSCH to change the terminal's DL BWP. In the case of an uplink carrier (or cell) operating as an FDD, the base station may include a BPI that indicates the BWP to be activated in the DCI that schedules the PUSCH to change the terminal's UL BWP.

[0149] Figure 8 is a conceptual diagram explaining carrier aggregation.

[0150] Carrier aggregation refers to a method by which a terminal utilizes multiple frequency blocks or (in a logical sense) cells, composed of uplink resources (or component carriers) and / or downlink resources (or component carriers), to form a single large logical frequency band, thereby enabling a wireless communication system to use a wider frequency band. A single component carrier may also be referred to as a PCell (Primary cell), SCell (Secondary Cell), or PScell ​​(Primary SCell). However, for the sake of convenience of explanation, the term "component carrier" will be used consistently below.

[0151] Referring to FIG. 8, as an example of a 3GPP NR system, the entire system band may include up to 16 component carriers, and each component carrier may have a bandwidth of up to 400 MHz. A component carrier may include one or more physically contiguous subcarriers. Although FIG. 8 depicts each component carrier as having the same bandwidth, this is merely an example, and each component carrier may have different bandwidths. Additionally, although each component carrier is depicted as being adjacent to each other in the frequency axis, the figure is illustrated in a logical sense, and each component carrier may be physically adjacent to each other or separated.

[0152] Different center frequencies may be used in each component carrier. Additionally, a common center frequency may be used in physically adjacent component carriers. In the embodiment of FIG. 8, assuming that all component carriers are physically adjacent, center frequency A may be used in all component carriers. Additionally, assuming that each component carrier is not physically adjacent, center frequency A and center frequency B may be used in each component carrier.

[0153] When the total system bandwidth is expanded through carrier aggregation, the frequency band used for communication with each terminal can be defined in terms of component carriers. Terminal A can use the total system bandwidth of 100 MHz and performs communication using all five component carriers. Terminals B1 through B5 can use only a 20 MHz bandwidth and perform communication using a single component carrier. Terminals C1 and C2 can use a 40 MHz bandwidth and each perform communication using two component carriers. The two component carriers may or may not be logically or physically adjacent. The embodiment of FIG. 8 illustrates a case where Terminal C1 uses two non-adjacent component carriers, and Terminal C2 uses two adjacent component carriers.

[0154] FIG. 9 is a diagram illustrating single-carrier communication and multi-carrier communication. In particular, FIG. 9(a) illustrates a subframe structure of a single carrier, and FIG. 9(b) illustrates a subframe structure of a multi-carrier.

[0155] Referring to FIG. 9(a), a typical wireless communication system can perform data transmission or reception through one DL band and a corresponding UL band in the case of FDD mode. In another specific embodiment, in the case of TDD mode, the wireless communication system can divide the wireless frame into an uplink time unit and a downlink time unit in the time domain and perform data transmission or reception through the uplink / downlink time units. Referring to FIG. 9(b), three 20MHz component carriers (CCs) can be aggregated in the UL and DL, respectively, to support a bandwidth of 60MHz. Each CC can be adjacent or non-adjacent to one another in the frequency domain. FIG. 9(b) illustrates a case where the bandwidths of the UL CC and the DL CC are both identical and symmetrical for convenience, but the bandwidths of each CC can be determined independently. Additionally, asymmetric carrier aggregation is possible where the number of UL CCs and the number of DL CCs are different. A DL / UL CC assigned / configured to a specific terminal via RRC can be referred to as the serving DL / UL CC of the specific terminal.

[0156] A base station can communicate with a terminal by activating some or all of the terminal's serving CCs or by deactivating some of the CCs. The base station may change the CCs that are activated / deactivated and may change the number of CCs that are activated / deactivated. If the base station allocates available CCs to the terminal in a cell-specific or terminal-specific manner, at least one of the CCs once allocated may not be deactivated unless the CC allocation to the terminal is completely reconfigured or the terminal undergoes a handover. One CC that is not deactivated to the terminal is referred to as the primary CC (PCC) or PCell (primary cell), and the CC that the base station can freely activate / deactivate is referred to as the secondary CC (SCC) or SCell (secondary cell).

[0157] Meanwhile, 3GPP NR uses the concept of a cell to manage radio resources. A cell is defined as a combination of downlink and uplink resources, that is, a combination of a DL CC and an UL CC. A cell can consist of a DL resource alone or a combination of a DL resource and an UL resource. Where carrier aggregation is supported, the linkage between the carrier frequency of a DL resource (or DL ​​CC) and the carrier frequency of a UL resource (or UL CC) can be indicated by system information. The carrier frequency refers to the center frequency of each cell or CC. A cell corresponding to a PCC is referred to as a PCell, and a cell corresponding to an SCC is referred to as a SCell. In the downlink, the carrier corresponding to a PCell is a DL PCC, and in the uplink, the carrier corresponding to a PCell is an UL PCC. Similarly, in the downlink, the carrier corresponding to a SCell is a DL SCC, and in the uplink, the carrier corresponding to a SCell is an UL SCC. Depending on the terminal capability, the serving cell(s) may consist of one PCell and zero or more SCells. For a UE in the RRC_CONNECTED state but where carrier aggregation is not enabled or does not support carrier aggregation, there is only one serving cell consisting only of PCells.

[0158] As previously mentioned, the term "cell" used in carrier aggregation is distinguished from the term "cell" which refers to a specific geographical area where communication services are provided by a single base station or a single antenna group. That is, a component carrier may also be referred to as a scheduling cell, a scheduled cell, a PCell (Primary cell), a SCell (Secondary Cell), or a PScell ​​(Primary SCell). However, in order to distinguish between a cell referring to a specific geographical area and a cell in carrier aggregation, the present invention refers to a cell in carrier aggregation as CC, and a cell in a geographical area as a cell.

[0159] FIG. 10 is a diagram illustrating an example in which a cross-carrier scheduling technique is applied. When cross-carrier scheduling is configured, a control channel transmitted through the first CC can schedule a data channel transmitted through the first CC or the second CC using a carrier indicator field (CIF). The CIF is included within the DCI. In other words, a scheduling cell is configured, and DL grants / UL grants transmitted in the PDCCH area of ​​the scheduling cell schedule the PDSCH / PUSCH of the scheduled cell. That is, a search area for multiple component carriers exists in the PDCCH area of ​​the scheduling cell. A PCell is basically a scheduling cell, and a specific SCell can be designated as a scheduling cell by an upper layer.

[0160] In the embodiment of FIG. 10, it is assumed that three DL CCs are merged. Here, DL component carrier #0 is assumed to be a DL PCC (or PCell), and DL component carrier #1 and DL component carrier #2 are assumed to be DL SCCs (or SCell). Additionally, it is assumed that the DL PCC is configured as a PDCCH monitoring CC. If cross-carrier scheduling is not configured by terminal-specific (or terminal-group-specific or cell-specific) upper-layer signaling, the CIF is disabled, and each DL CC can transmit only the PDCCH that schedules its own PDSCH without a CIF according to the NR PDCCH rule (non-cross-carrier scheduling, self-carrier scheduling). On the other hand, when cross-carrier scheduling is configured by terminal-specific (or terminal-group-specific or cell-specific) upper-layer signaling, CIF is enabled, and a specific CC (e.g., DL PCC) can use CIF to transmit not only the PDCCH that schedules the PDSCH of DL CC A but also the PDCCH that schedules the PDSCH of another CC (cross-carrier scheduling). On the other hand, no PDCCH is transmitted from other DL CCs. Therefore, depending on whether cross-carrier scheduling is configured for the terminal, the terminal monitors the PDCCH that does not contain CIF to receive the self-carrier scheduled PDSCH, or monitors the PDCCH that contains CIF to receive the cross-carrier scheduled PDSCH.

[0161] Meanwhile, FIGS. 9 and 10 illustrate the subframe structure of a 3GPP LTE-A system, but the same or similar configuration may also be applied to a 3GPP NR system. However, in a 3GPP NR system, the subframes of FIGS. 9 and 10 may be replaced with slots.

[0162] FIG. 11 is a block diagram showing the configuration of a terminal and a base station, respectively, according to an embodiment of the present invention.

[0163] In an embodiment of the present invention, the terminal may be implemented as various types of wireless communication devices or computing devices that ensure portability and mobility. The terminal may be referred to as a User Equipment (UE), Station (STA), Mobile Subscriber (MS), etc. Additionally, in an embodiment of the present invention, the base station may control and manage cells (e.g., macro cells, femto cells, pico cells, etc.) corresponding to a service area, and perform functions such as signal transmission, channel assignment, channel monitoring, self-diagnosis, and relay. The base station may be referred to as a Next Generation Node (gNB) or Access Point (AP), etc.

[0164] As described above, a terminal (100) according to one embodiment of the present invention may include a processor (110), a communication module (120), a memory (130), a user interface unit (140), and a display unit (150).

[0165] First, the processor (110) can execute various commands or programs and process data within the terminal (100). Additionally, the processor (110) can control the overall operation including each unit of the terminal (100) and control the transmission and reception of data between the units. Here, the processor (110) may be configured to perform operations according to the embodiment described in the present invention. For example, the processor (110) may receive slot configuration information, determine the configuration of the slot based thereon, and perform communication according to the determined slot configuration.

[0166] Next, the communication module (120) may be an integrated module that performs wireless communication using a wireless communication network and wireless LAN access using a wireless LAN. To this end, the communication module (120) may be equipped with a plurality of network interface cards (NICs), such as cellular communication interface cards (121, 122) and unlicensed band communication interface cards (123), either internally or externally. Although the communication module (120) is depicted as an integrated module in the drawing, each network interface card may be arranged independently according to circuit configuration or purpose, unlike in the drawing.

[0167] A cellular communication interface card (121) can transmit and receive wireless signals with at least one of a base station (200), an external device, and a server using a mobile communication network, and can provide cellular communication services in a first frequency band based on instructions from a processor (110). According to one embodiment, the cellular communication interface card (121) may include at least one NIC module using a frequency band of less than 6 GHz. At least one NIC module of the cellular communication interface card (121) can independently perform cellular communication with at least one of a base station (200), an external device, and a server according to a cellular communication standard or protocol of a frequency band of less than 6 GHz supported by the NIC module.

[0168] A cellular communication interface card (122) can transmit and receive wireless signals with at least one of a base station (200), an external device, and a server using a mobile communication network, and can provide cellular communication services in a second frequency band based on instructions from a processor (110). According to one embodiment, the cellular communication interface card (122) may include at least one NIC module using a frequency band of 6 GHz or higher. At least one NIC module of the cellular communication interface card (122) can independently perform cellular communication with at least one of a base station (200), an external device, and a server according to a cellular communication standard or protocol of a frequency band of 6 GHz or higher supported by the NIC module.

[0169] The unlicensed band communication interface card (123) transmits and receives wireless signals with at least one of a base station (200), an external device, and a server using a third frequency band which is an unlicensed band, and provides unlicensed band communication services based on instructions from a processor (110). The unlicensed band communication interface card (123) may include at least one NIC module that uses the unlicensed band. For example, the unlicensed band may be a band of 2.4 GHz, 5 GHz, 6 GHz, 7 GHz, or 52.6 GHz or higher. At least one NIC module of the unlicensed band communication interface card (123) may perform wireless communication with at least one of a base station (200), an external device, and a server independently or dependently according to the unlicensed band communication standard or protocol of the frequency band supported by the NIC module.

[0170] Next, the memory (130) stores a control program used in the terminal (100) and various data associated therewith. This control program may include a specific program required for the terminal (100) to perform wireless communication with at least one of a base station (200), an external device, and a server.

[0171] Next, the user interface (140) includes various types of input / output means provided in the terminal (100). That is, the user interface (140) can receive user input using various input means, and the processor (110) can control the terminal (100) based on the received user input. In addition, the user interface (140) can perform output based on the command of the processor (110) using various output means.

[0172] Next, the display unit (150) outputs various images to the display screen. The display unit (150) can output various display objects, such as content executed by the processor (110) or a user interface based on control commands of the processor (110).

[0173] In addition, a base station (200) according to one embodiment of the present invention may include a processor (210), a communication module (220), and a memory (230).

[0174] First, the processor (210) can execute various commands or programs and process data within the base station (200). Additionally, the processor (210) can control the overall operation including each unit of the base station (200) and control the transmission and reception of data between the units. Here, the processor (210) may be configured to perform operations according to the embodiment described in the present invention. For example, the processor (210) may signal slot configuration information and perform communication according to the signaled slot configuration.

[0175] Next, the communication module (220) may be an integrated module that performs wireless communication using a wireless communication network and wireless LAN access using a wireless LAN. To this end, the communication module (220) may be equipped with a plurality of network interface cards, such as cellular communication interface cards (221, 222) and unlicensed band communication interface cards (223), in an internal or external form. Although the communication module (220) is shown as an integrated module in the drawing, each network interface card may be arranged independently according to circuit configuration or purpose, unlike in the drawing.

[0176] A cellular communication interface card (221) can transmit and receive wireless signals with at least one of the above-described terminal (100), external device, and server using a mobile communication network, and can provide cellular communication services in a first frequency band based on instructions from a processor (210). According to one embodiment, the cellular communication interface card (221) may include at least one NIC module using a frequency band of less than 6 GHz. At least one NIC module of the cellular communication interface card (221) can independently perform cellular communication with at least one of the terminal (100), external device, and server according to a cellular communication standard or protocol of a frequency band of less than 6 GHz supported by the NIC module.

[0177] A cellular communication interface card (222) can transmit and receive wireless signals with at least one of a terminal (100), an external device, and a server using a mobile communication network, and can provide cellular communication services in a second frequency band based on instructions from a processor (210). According to one embodiment, the cellular communication interface card (222) may include at least one NIC module using a frequency band of 6 GHz or higher. At least one NIC module of the cellular communication interface card (222) can independently perform cellular communication with at least one of a terminal (100), an external device, and a server according to a cellular communication standard or protocol of a frequency band of 6 GHz or higher supported by the NIC module.

[0178] The unlicensed band communication interface card (223) transmits and receives wireless signals with at least one of a terminal (100), an external device, and a server using a third frequency band which is an unlicensed band, and provides unlicensed band communication services based on instructions from a processor (210). The unlicensed band communication interface card (223) may include at least one NIC module that uses the unlicensed band. For example, the unlicensed band may be a band of 2.4 GHz, 5 GHz, 6 GHz, 7 GHz, or 52.6 GHz or higher. At least one NIC module of the unlicensed band communication interface card (223) may perform wireless communication with at least one of a terminal (100), an external device, and a server independently or dependently according to the unlicensed band communication standard or protocol of the frequency band supported by the NIC module.

[0179] The terminal (100) and base station (200) illustrated in FIG. 11 are block diagrams according to an embodiment of the present invention, wherein the separated blocks represent logically distinguished elements of the device. Accordingly, the elements of the device described above may be mounted as a single chip or as a plurality of chips depending on the design of the device. In addition, some components of the terminal (100), such as a user interface (140) and a display unit (150), may be optionally provided in the terminal (100). Furthermore, the user interface (140) and the display unit (150), etc., may be additionally provided in the base station (200) as needed.

[0180] FIG. 12 is a diagram showing the topology of an Ambient IoT (Internet of Everything) according to one embodiment of the present invention.

[0181] Ambient IoT (A-IoT) systems can operate based on a concept similar to UHF (Ultra-High Frequency Radio Frequency Identification) RFID. In A-IoT systems, technology can be applied that uses radio waves in the ultra-high frequency band (between 300 MHz and 3 GHz) to wirelessly transmit data between tags and readers. A-IoT systems can read or write information from RFID tags attached to objects or people and can be primarily used for supply chain management, logistics, inventory management, and asset tracking.

[0182] One of the characteristics of UHF RFID is its long reading distance and fast data transmission speed. In the UHF band, tag information can be read from a distance of approximately 3 to 10 meters or more, and data can be read even when the tag is moving. For example, UHF RFID can be used to automatically track goods in a warehouse or to automatically calculate tolls using tags attached to vehicles on the road.

[0183] The main components of UFH RFID may be RFID tags and RFID readers. An RFID tag is a small chip attached to an object that can transmit information via radio waves. RFID tags can also be classified into read-only or read / write tags. An RFID reader is a device that receives signals transmitted from an RFID tag and decodes them. An RFID reader can transmit signals to RFID tags and collect data from RFID tags that respond to the transmitted signals.

[0184] There can be various topologies that constitute an A-IoT system. The following is an explanation of the basic terms used in topology.

[0185] CW Node: A node that transmits a Carrier Wave (CW). An A-IoT terminal can receive the CW and transmit a response signal via backscattering. Among A-IoT terminals, those without a separate power supply can receive the CW, convert it into the necessary power, and store it to perform terminal operations.

[0186] Reader (R): In an A-IoT system, the reader may be a device that manages communication with A-IoT terminal(s). Depending on the topology configuration, the reader may be a gNB / NR BS / intermediate node (UE).

[0187] Device (D): In an A-IoT system, a device can be a device that communicates with a reader. Devices can be classified into three types as follows.

[0188] - Device 1: Device 1 operates with a peak power consumption of less than 1 sW, may have an energy storage device, and the initial sampling frequency offset (SFO) may be up to 10^X ppm. Device 1 may not have amplification during downlink and uplink channel transmission. Uplink channel transmission in Device 1 may transmit a backscattered signal based on an externally applied CW.

[0189] - Device 2a: Device 2a operates with a peak power consumption of a few hundred (a few hundred) sW or less, may have an energy storage device, and the SFO may be up to 10^X ppm. Device 2a may be capable of amplifying the signal during downlink channel and / or uplink channel transmission. Uplink channel transmission in Device 2a may be the transmission of a backscattered signal based on an externally applied CW.

[0190] - Device 2b: Device 2b operates with a peak power consumption of a few hundred sW or less, may have an energy storage device, and the SFO may be up to 10^X ppm. Device 2b may be capable of amplifying the signal during uplink channel and / or downlink channel transmission. Uplink channel transmission in Device 2b may be the transmission of a signal generated internally within the device.

[0191] Device 2b has a relatively more complex configuration than devices 1 and 2a and may have superior performance.

[0192] Base Station (BS): The BS can be an NR BS / NR indoor BS / gNB (gNodeB), and the BS can communicate with a reader.

[0193] CW2D: CW2D can refer to the transmission of CW from a CW node to a device.

[0194] R2D: R2D may refer to the transmission of data from a reader to a device. Depending on the case, it may also be referred to as a downlink (DL).

[0195] D2R: D2R may refer to data transmission from a device to a reader. Depending on the case, it may also be referred to as an uplink (UL).

[0196] Referring to FIG. 12(a), the CW node may exist within topology 1, and the CW node transmitting CW2D and R2 receiving D2R may be different nodes. The CW node transmitting CW2D and R1 transmitting R2D may be the same node.

[0197] Referring to Fig. 12(b), the CW node may exist within Topology 1, and the CW node and R transmitting / receiving CW2D, D2R, and R2D may be the same node.

[0198] Referring to FIG. 12(c), the CW node may exist within topology 2, and the CW node and R transmitting / receiving CW2D, D2R, and R2D may be the same node. The BS can communicate with R using an existing cellular communication method.

[0199] Topology 1 and Topology 2 described in this specification may be distinguished based on whether indoor-to-indoor communication or indoor-to-outdoor communication is used in a deployment scenario.

[0200] In indoor-to-indoor communication, an indoor microcell base station may exist (see Fig. 12(a), (b). In indoor-to-indoor communication, an indoor UE may exist as an intermediate node receiving network control from an outdoor macrocell base station (see Fig. 12(c)).

[0201] The A-IoT system can operate in Inventory mode and Command mode, and can operate in Inventory mode only or in both Inventory and Command modes.

[0202] - Inventory Mode: Inventory mode may be a mode performed by the network to search for A-IoT device identifiers and collect A-IoT devices.

[0203] - Command Mode: Command mode can be a mode (e.g., read, write) that the network performs to transmit work instructions to A-IoT devices.

[0204] FIG. 13 is a diagram illustrating a random access operation in an A-IoT system according to one embodiment of the present specification.

[0205] Random access operation may be the process by which a terminal registers to communicate with a network / base station. Random access operation may be conceptually similar to inventory mode and may be described interchangeably. Random access operation can be classified into two types.

[0206] - Step 2 operation: i) The reader can send a paging message to the device. ii) The device that receives the paging message can send its unique identifier, DeviceID, to the reader (see FIG. 13(a)).

[0207] - Step 4 Operation: i) The reader may send a paging message to the device. The first paging message sent by the reader to the device(s) for inventory may be described as Message-0 (Msg-0). ii) The device that receives the paging message may send ID information to the reader. The ID information may be a random ID of a fixed length or a DeviceID, which is the unique identifier of the device. The response message (ID information) sent by the device to the reader after receiving the paging information may be described as Message-1 (Msg-1). iii) The reader may send the random ID included in Msg-1 and additional information to the device. In this case, the message sent by the reader may be described as Message-2 (Msg-2). iv) The device may send the DeviceID to the reader. Additionally, the device may send upper-layer data to the reader if there is a request from the upper layer. In this case, the message sent by the device may be described as Message-3 (Msg-3). v) Additionally, if the reader fails to receive Msg-3, the reader may send Message-4 (Msg-4) to manage random access operations. Msg-4 may not always be required for random access operations.

[0208] Messages transmitted by a reader to a device can be described as R2D, and R2D can be transmitted via PRDCH (Physical reader-to-device channel). Messages transmitted by a device to a reader can be described as D2R, and D2R can be transmitted via PDRCH (Physical device-to-reader channel).

[0209] FIG. 14 is a diagram illustrating the process of generating information of PRDCH according to one embodiment of the present specification.

[0210] PRDCH can be the channel used when a reader transmits data to a device.

[0211] Referring to Fig. 14(a), the R2D information bits can be coded by line coding with added CRC information. Then, the coded data can be transmitted using an OFDM waveform generated using OOK (On-off keying)-1 / OOK-4 modulation.

[0212] Referring to FIG. 14(b), the PRDCH may be transmitted immediately after the preamble. The preamble may consist of a start indicator part and a time acquisition part. The start indicator part may serve to inform the device of the start time of the message transmitted by the reader, and the time acquisition part may serve to synchronize the time of the device with the reader, which is necessary when receiving a subsequent PRDCH. The R2D information bits may be R2D control information. The R2D control information may include the following information.

[0213] - Time domain resource allocation

[0214] - Frequency domain resource allocation

[0215] - MCS (Modulation and coding scheme)

[0216] - TBS(Transport Block Size)

[0217] - Chip duration

[0218] - Early indication (information in which the reader indicates to the device that the reception of the subsequent PRDCH may be skipped, considering the device's state)

[0219] FIG. 15 is a diagram illustrating the process of generating information of PDRCH according to one embodiment of the present specification.

[0220] PDRCH may be a channel used when a device transmits data to a reader.

[0221] Referring to FIG. 15(a), D2R information bits can be coded with added CRC information. The coded data can then be transmitted using modulation. The D2R information bits may be D2R control information. The D2R control information may include the following information.

[0222] - MCS (Modulation and Coding Techniques, e.g., Data Modulation, Line / Channel Coding)

[0223] - Receiving methods (receiving techniques, e.g., coherent or non-coherent)

[0224] - D2R transmission length / packet size

[0225] - Midamble overhead

[0226] - Timing / frequency accuracy

[0227] - Phase accuracy

[0228] FIG. 16 is a drawing showing line coding according to one embodiment of the present specification.

[0229] Specifically, Fig. 16 is a diagram showing FM0, which is one of the line coding methods.

[0230] FM0 can be used as a coding method for the data (information) included in PRDCH and PDRCH, as described with reference to FIGS. 14 and 15. FIG. 16(a) shows the transmission waveform shape of the symbols for data-0 and data-1, which are the basic symbols of the FM0 code. Data-0 has a change in waveform magnitude in the middle, while data-1 can be maintained without a change in waveform. From the basic symbols, there may be two possible symbol forms of FM0 representing data-0 and two methods representing data-1. FIG. 16(b) shows a method for constructing / coding data sequences such as "00", "01", "10", and "11" from the basic symbols of FM0.

[0231] FIG. 17 is a diagram showing a Miller code among line coding methods according to one embodiment of the present specification.

[0232] Miller codes can be used as a coding method for the data (information) included in PRDCH and PDRCH, as described with reference to FIGS. 14 and 15. FIG. 17(a) shows the transmission waveform shape of the symbols for data-0 and data-1, which are the basic symbols of the Miller code. Data-0 is maintained without change in waveform, while data-1 may have a change in waveform magnitude in the middle. From the basic symbols, the shape of the Miller code can be adjusted through the parameter of the number of subcarrier cycles per symbol. The parameter can be M, and M can be 2, 4, or 8 and can be extended to various values. Based on the value of M, the number of subcarrier cycles per symbol can be increased. If the same information is transmitted repeatedly using the increased number of subcarrier cycles per symbol, the transmission speed of the actual information data may remain the same or decrease. If different information is transmitted using the increased number of subcarrier cycles per symbol, the transmission speed of the actual information data may increase. Figure 17(b) illustrates a case where the same information is transmitted repeatedly using an increased number of subcarrier cycles per symbol.

[0233] Square-wave coding can also be used in line coding methods, unlike those shown in FIGS. 16 and 17.

[0234] FIG. 18 is a diagram illustrating the inventory process of an A-IoT system according to one embodiment of the present specification.

[0235] Specifically, FIG. 18 illustrates an operation consisting of the four steps described above within the inventory method. Referring to FIG. 18, the inventory for a single device is terminated by completing the transmission and reception of Msg-0 through Msg-3 in Inventory round #N, and the next Inventory round #N+1 can proceed. The timing relationships for the transmission of each message will be explained below with reference to FIG. 18.

[0236] - T R2D_min : Minimum time between R2D transmission and the D2R transmission corresponding to the R2D transmission

[0237] - T D2R_min : Minimum time between D2R transmission and the R2D transmission corresponding to the D2R transmission

[0238] - T R2D_R2D_min : Minimum time between consecutive R2D transmissions sent to the same device

[0239] - T D2R_D2R_min : Minimum time between consecutive D2R transmissions from the same device

[0240] FIG. 19 is a diagram illustrating multiple access to Msg-1 in an inventory process according to one embodiment of the present specification.

[0241] FIG. 19(a) illustrates multiple access in the frequency domain for devices transmitting response messages to the leader's paging message during the inventory process. The leader and the devices can each set multiple frequency domain resources in the frequency domain, and the devices can transmit Msg-1 to the leader using the leader's resource allocation or a frequency domain resource randomly selected from pre-configured resources. The frequency domain resource allocation method is not limited to Msg-1 but can also be applied to subsequent messages (e.g., Msg-3) and communication in command mode.

[0242] FIG. 19(b) illustrates multiple access in the time domain for devices transmitting response messages to the leader's paging message during the inventory process. The leader and the devices can each set multiple time domain resources in the time domain, and the devices can transmit Msg-1 to the leader using the leader's resource allocation or a time domain resource randomly selected from among the pre-configured resources. The time domain resource allocation method is not limited to Msg-1 but can also be applied to subsequent messages (e.g., Msg-3) and communication in command mode.

[0243] Alternatively, by combining the resource allocation methods described in FIG. 19(a) and FIG. 19(b), frequency domain resource and time domain resource allocation can be performed simultaneously. When multiple resource allocations are made, the device has more random access transmission opportunities, and inventory time can be reduced when multiple devices are present. As a result, transmission delay is reduced and the overall efficiency of the A-IoT system can be increased.

[0244] FIG. 20 is a diagram showing the resource allocation of PDRCH transmitted by a device to a reader in an A-IoT system according to one embodiment of the present specification.

[0245] A device that receives a paging message from a reader can send a response message to the reader. Resources for PDRCH are divided into multiple frequency domains, and in some frequency domains, they can also be divided into multiple resources in the time domain. In UHF RFID, the frequency of the resource used when a device transmits a message to a reader can be defined as BLF (Backscatter Link Frequency), and BLF can be used as a variable to manage D2R data encoding and D2R data rates. BLF can be a value between a minimum of 40 kHz and a maximum of 640 kHz. If the BLF is 40 kHz, 16 times more transmission time is required for message transmission compared to when it is 640 kHz. Relatively speaking, if the BLF increases, the time required to transmit the same message can be shortened due to the increase in transmission bandwidth. Based on the same transmission time, it becomes possible to transmit more messages (i.e., additional messages) when a larger BLF is used compared to when a relatively smaller BLF is used. When a relatively large BLF is used, since there are many messages that can be transmitted within the same time domain, resource allocation to other devices may be possible.

[0246] FIG. 20(a) illustrates an example of a resource allocation method for a device sending a response message to a paging message. Referring to FIG. 20(a), multiple resource allocations can be made in the frequency domain, and the available frequency domains can be distinguished by device type. For example, the frequency domain can be divided into six resources, and devices 1 and / or 2a can use four resources from f1 to f4, while devices 2a and / or 2b can use all six resources from f1 to f6. Frequency domain resource f1 may be a relatively small BLF, and frequency domain resources with a larger index may be BLFs that are relatively larger than the BLF of f1. The larger the frequency domain resource index value, the larger the BLF may be. Device 2b can perform D2R transmission using all frequencies, whereas devices 1 and 2a can perform D2R transmission using only some frequency resources.

[0247] From the perspective of transmission time, since BLFs f2 through f4 have a wider bandwidth compared to the smallest BLF, f1, the transmission time for sending the same message can be reduced in f2 through f4. Therefore, multiple messages can be transmitted via f2 through f4 during the single message transmission time utilizing f1. For frequency domain resource indices f5 and f6, multiple time domain divisions may also be possible based on the BLF and sampling clock frequency. When using a frequency domain with a relatively large BLF, the transmission success rate can be increased through the repeated transmission of the same information. Therefore, in the case of resource allocation for certain frequency domains, the time domain resources for repeated transmission by the same device and the time domain resources available for transmission by other terminals can be integrated to allocate the frequency resources.

[0248] The leader can instruct the resource allocation method through paging (PRDCH) messages. The resource allocation method using paging messages is described below.

[0249] Resources can be indicated by {frequency domain resource, time domain resource} information. For example, frequency domain resources can be BLF values ​​or index values ​​mapped to BLF values. Time domain resources can be slot indices, indices of mini-slots within a single slot, slot and mini-slot indices, or time information (e.g., time distance information from PRDCH). Slots and mini-slots can be distinguished by time information and mapped to index values.

[0250] Alternatively, information indicating a resource can be composed of {frequency domain resource, modulation, time domain resource}. That is, resources can be distinguished by adding information about the modulation to the information indicating the resource. Since modulation can vary depending on the modulation order, the information indicating the resource may also include information about the modulation order.

[0251] Alternatively, information indicating resources may include information regarding frequency domain resources, time domain resources, modulation order, device type, DSB (Double sideband) / SSB (Single sideband), and BLF. Frequency domain resources may be in the form of frequency shift values, frequency positions, or indices of pre-defined frequency domains; time domain resources may be distinguished by time positions; and modulation order may be distinguished as Miller encoding order or Square Wave with frequency order. Additionally, available resources may be mapped by device type, and mapped resources may be distinguished as resources allocated to DSB, resources allocated to SSB, or resources capable of using either DSB or SSB. Furthermore, mapped resources may be distinguished by the BLF value of the frequency resource. The value of the BLF may change based on the encoding method and the modulation method.

[0252] FIG. 20(b) is a diagram that re-represents the frequency domain of FIG. 20(a) by considering the relativity of frequency bandwidth sizes for each BLF. Frequency domain resources f5 and f6 can be divided into a larger BLF and multiple time domain resources in the frequency domain based on the BLF / sampling clock frequency. The resource allocation method of this specification is not limited to the transmission of Msg-1 and can also be applied to the resource allocation of PDRCH transmitted subsequently.

[0253] FIG. 21 shows the resource allocation of PDRCH transmitted by a device to a reader in an A-IoT system according to one embodiment of the present specification.

[0254] Referring to Fig. 21, resource allocation in PDRCH can be distinguished based on time gaps.

[0255] In frequency / time domain resource allocation, a relatively large BLF can be divided into multiple time domain resources within the same time period due to a wider frequency bandwidth. In this case, a time gap can be set for each time domain resource, and the transmission timing can be distinguished accordingly. Since the device has a relatively large Sampling Frequency Offset (SFO) value, the clock frequency may differ for each device. If the transmission timings of devices performing data transmission in different time domain resources within the same frequency domain resource overlap even partially, it can act as an interference factor when the reader receives messages, potentially causing a degradation in reception performance. Considering this problem, a fixed time interval can be set between each time domain resource, and each time domain resource can be allocated separately. By considering the additional time interval, the size of the time domain resource allocation can be relatively reduced compared to FIG. 20.

[0256] FIG. 22 is a diagram illustrating a method for allocating frequency / time domain resources by considering a plurality of time slots according to one embodiment of the present specification.

[0257] FIG. 22 illustrates an example of allocating resources by extending the frequency / time domain resource allocation method described in FIG. 21(a) to multiple time slots. In a resource allocation method considering multiple time slots, information (index) regarding the number of time slots may be additionally considered in the resource allocation method described above. For example, time domain resources included in the information indicating resources can be classified into time slot resources and mini-slot resources. A time gap (interval) between time slots is required, and the start time of each individual time slot can be inferred from the transmission time of the paging message through the size of a single time slot and the time gap between time slots, or can be indicated separately. Mini-slots can be defined as individual time intervals based on time slots. Resource allocation can be indicated by {frequency domain index, time slot index, mini-slot index}. For example, resource allocation can be indicated by {4, (3, (1, 2, 3, 4))}. This may indicate 4 frequency resources, 3 time slot resources, and 1, 2, 3, and 4 mini-slot resources for each frequency resource. Alternatively, resource allocation may be indicated as {4, (3, (YES))}. This may indicate 4 frequency resources, 3 time slot resources, and that mini-slots are allocated (YES) for each frequency resource. Devices receiving information indicating resource allocation may implicitly calculate the number of allocatable mini-slots (e.g., 1, 2, 3, 4) for each frequency resource by considering the length of each time slot, the BLF frequency bandwidth, and the time gap between mini-slots. Additionally, the modulation order may be added to the information indicating resource allocation. The resource allocation method described above is not limited to Msg-1 but may be applied to subsequent messages as well.

[0258] FIG. 23 is a diagram illustrating a method for transmitting PRDCH / PDRCH considering a plurality of frequency / time domain resource allocation methods according to one embodiment of the present specification.

[0259] FIG. 23(a) illustrates the relationship regarding resource allocation and transmission for Msg-0 (Paging) / Msg-1 / Msg-2 / Msg-3 transmitted during the inventory process. For example, in Time slot #N, multiple devices transmit response messages to the paging message, and the reader can transmit a response message to the response messages transmitted by the multiple devices. At this time, the reader successfully receives the response message to the paging message and can transmit Msg-2 and Msg-3 to one of the multiple devices that transmitted the successfully received response message. A device that confirms the reception of Msg-2 within a limited time can transmit Msg-3 on the same frequency / time resource that sent Msg-1 without a separate resource allocation instruction. Alternatively, if a separate resource allocation is indicated via Msg-2, the device can transmit Msg-3 on the indicated resource. The resource allocation classification for Msg-3 may be the same as the resource allocation classification for Msg-1. If the resource allocation division of Msg-3 is different from the resource allocation division of Msg-1, an indicator for the transmitted resource area of ​​Msg-3 may be transmitted.

[0260] FIG. 23(b) illustrates a method of transmitting Msg-1 through a single PRDCH. Devices receiving the paging message may transmit Msg-3 on the same frequency / time resource where Msg-1 was transmitted, without separate resource allocation instruction information. Alternatively, each device may transmit Msg-3 on a resource determined based on the device-specific resource allocation instruction included in Msg-2. The reader may perform resource allocation so that frequency resources do not overlap temporally to advance the transmission time or to minimize interference in the frequency domain or time domain.

[0261] FIGS. 24 and 25 illustrate a method for transmitting PRDCH / PDRCH considering a time gap in a plurality of frequency / time domain resource allocations according to one embodiment of the present specification.

[0262] FIGS. 24(a) and (b) respectively show resources allocated by taking into account the time gap in the mini-slot within the slot in the resource allocation of FIGS. 23(a) and (b). The maximum number of mini-slots can be reduced by the amount of the time gap added.

[0263] FIG. 25 illustrates a method for transmitting Msg-3 through a mini-slot at an earlier time point when the device in FIG. 23(b) performs Msg-3 transmission for multiple Msg-2s. The earlier time point can be indicated by a resource allocation indicator. By transmitting Msg-3 at the earliest possible time point, the device can reduce response delay time, and the reader can prepare for subsequent processes.

[0264] FIG. 26 is a diagram showing the transmission relationship of a plurality of PRDCHs in a plurality of frequency / time domain resource allocation methods considering a time gap according to one embodiment of the present specification.

[0265] In response to multiple Msg-1s, the reader may use multiple PRDCHs to sequentially transmit Msg-2 to each device. A device receiving a PRDCH may transmit Msg-3 using the resource location where Msg-1 was transmitted, without separate resource instruction information. Alternatively, the reader may transmit resource allocation instruction information in each Msg-2, and the device may transmit Msg-3 from a resource determined based on the resource allocation instruction information. The reader may allocate resources to minimize interference between frequency / time domain resources and to receive Msg-3 from multiple devices in the shortest possible time.

[0266] FIG. 27 is a diagram showing the time relationship for the transmission of a plurality of Msg-1s and the transmission of a plurality of Msg-2s according to one embodiment of the present specification.

[0267] Referring to FIG. 27, multiple devices that have received a paging message transmitted by a reader may transmit Msg-1 using PDRCH on multiple time-domain resources. The multiple time-domain resources may be the same or different depending on the transmission timing and length of Msg-1. Considering system efficiency and interference, a minimum time interval between PDRCHs transmitted by different devices may be required to prevent transmission timings from overlapping. The minimum time interval between PDRCHs can be described as TD2R_D2R_min for different devices. Additionally, the reader may transmit Msg-2, which is a multiple response message to multiple Msg-1s, using PDRCH. When transmitting Msg-2, a minimum time interval between consecutively transmitted PRDCHs may also be defined and applied. The minimum time interval between PRDCHs can be described as TR2D_R2D_min for different devices. Furthermore, the pre-configured T R2D_maxcan be set to a separate value. T when multiple Msg-1s are transmitted R2D_max T when a single Msg-1 is transmitted R2D_max It can be determined as a multiple of the value. The multiple value may be the number of transmissions of Msg-1. Or, T when multiple Msg-1s are transmitted. R2D_max T when a single Msg-1 is transmitted R2D_max It may be a value obtained by adding a value set at regular time intervals from. Defines the maximum value of the interval between the time when the paging message is received complete and the time when Msg-1 is transmitted when a single Msg-1 is transmitted. TR2D_max The value corresponding to, and when multiple Msg-1s are transmitted, T R2D_max Values ​​are distinct from each other and can be defined differently. When a single Msg-1 is transmitted, T R2D_max is T R2D_max_signleSlot As such, when multiple Msg-1s are transmitted, T R2D_max The value is T R2D_max_multiSlot It can be described as.

[0268] The reader can send multiple Msg-2s in response to multiple Msg-1s. T R2D_max It can be set after the previously configured last PDRCH transmission resource. Additionally, between the last transmission time of Msg-1 and the first transmission time of Msg-2, T D2R_min A larger time interval must be maintained. For example, if there is only one device transmitting Msg-1 and it transmits PDRCH at the time of the last transmission, the reader must consider that Msg-2 may be transmitted at the time of the first PRDCH transmission. D2R_max is T R2D_max It can start from the value.

[0269] FIG. 28 is a diagram showing the time relationship between a plurality of Msg-1 transmissions and a single Msg-2 transmission according to one embodiment of the present specification.

[0270] Referring to FIG. 28, multiple devices that receive a paging message transmitted by a reader may transmit Msg-1 over complementary time-domain resources. In response to Msg-1, the reader may transmit multiple Msg-2s included in a single PRDCH. In this case, the time interval between the last PDRCH and PRDCH is T D2R_min_a It must be larger than T D2R_min_a The start time of can be the end time of the last PDRCH transmission. T R2D_max Starting from the value T D2R_min_b The value of can be defined. T R2D_max T with the value as the starting point D2R_max_a The value can be defined. Or, based on the start / end time of the last transmission of Msg-1, T D2R_max_b The value of can be defined.

[0271] FIG. 29 is a diagram showing the transmission relationship of Msg-1 using a plurality of frequency domain resources according to one embodiment of the present specification.

[0272] Referring to FIG. 29, resource allocation for Msg-1 can be made using multiple frequency domain resources. For example, two different devices can transmit Msg-1 simultaneously using two frequency resource domains. A reader that receives Msg-1 transmits Msg-2 to device A, and in response to Msg-2, device A can transmit Msg-3 to the reader. Subsequently, Msg-2 is transmitted to another device B, and in response to Msg-2, device B can transmit Msg-3 to the reader. D2R_max can be configured differently depending on the device. T D2R_max T when there is only one resource in the frequency domain D2R_max It can be defined as the value multiplied by the number of frequency resource regions.

[0273] FIG. 30 is a diagram showing an FDM method for Msg-1 according to one embodiment of the present specification.

[0274] Referring to FIG. 30(a), the device can divide the frequency domain into multiple resources and transmit Msg-1 for each resource in a single time transmission opportunity. Each frequency domain resource may have different BLF values. If the BLF values ​​differ, the transmission times may differ relatively when transmitting the same amount of information. FDM can be achieved by distinguishing resources based only on identical BLF values. Assuming the amount of information in Msg-1 is similar, multiple resources can be configured with identical BLF values. The BFL value can be set based on the amount of data being responded to, and the BFL value can be indicated in a paging message or in the preceding PRDCH information. The FDM method is not limited to Msg-1 transmission but can also be applied to subsequent PDRCH transmissions.

[0275] FIG. 30(b) illustrates how a device transmits a message at different times for each frequency resource. When FDM is applied, interference may occur between adjacent frequency resources. To address this, the reader can indicate the transmission time for each frequency resource. For example, the reader can indicate the time position for each frequency domain starting from the end of the received signal of the paging message.

[0276] FIG. 31 is a diagram showing the transmission relationship of Msg-1, Msg-2, and Msg-3 according to one embodiment of the present invention.

[0277] Specifically, FIG. 31 shows the relationship between the transmission of Msg-1 in a frequency multiplexing situation, the transmission of Msg-2 in a time multiplexing situation, and the transmission of Msg-3 in a frequency multiplexing situation.

[0278] Referring to FIG. 31, the device can transmit Msg-1, a response message to a paging message, to the reader using frequency domain multiplexing. The reader can transmit Msg-2, a response message to Msg-1, to the device using time domain multiplexing. Since Msg-2 is transmitted multiple times in the time domain, and all devices that receive Msg-2 must transmit Msg-3 in the frequency domain at the same time, T R2D_max The value can be set from the first Msg-2 or the last Msg-2. PRDCH can be received by all devices. If the PRDCH in which Msg-2 is transmitted is the last transmission, the reader may include information in the last transmitted PRDCH indicating that Msg-2 is the last PRDCH. Through this information indicating the last PRDCH, the device can stop further monitoring and prepare for subsequent actions.

[0279] FIG. 32 is a diagram illustrating the transmission of Msg-2 in a time domain resource as a partial response to Msg-1 according to one embodiment of the present specification.

[0280] FIG. 32 illustrates a method for transmitting Msg-2 by allocating time resources for Msg-2 as far forward as possible when the response to Msg1- is not present in all resources but only in some resources. The time interval for transmitting Msg-3 can be adjusted through the PRDCH (see FIG. 31) that transmits the last Msg-2. Time / frequency domain resource allocation for Msg3 can be indicated through the PRDCH containing Msg-3.

[0281] FIG. 33 is a diagram illustrating a frequency domain multiplexing method using different BLFs according to one embodiment of the present specification.

[0282] Referring to Fig. 33, frequency domain resources can use different BLF values.

[0283] The timing-related parameters described in FIGS. 27 to 29 can be determined based on BLF values. The timing-related parameters may be as follows.

[0284] T R2D_min : Minimum time between an R2D transmission and the corresponding D2R transmission following it

[0285] T D2R_min : Minimum time between a D2R transmission and the corresponding R2D transmission following it

[0286] T D2R_max : When Msg-2 is transmitted as a response to Msg-1 in an A-IoT device, the maximum time from the D2R transmission to the corresponding R2D transmission, the R2D transmission time is [T D2R_min , T D2R_max Expected to be within the ] interval (Maximum time between the D2R transmission and the corresponding R2D transmission following it, so that the R2D transmission timing is expected to be within [T D2R_min , T D2R_max ], when a R2D transmission in response to a D2R transmission is expected for A-IoT Msg2 response to A-IoT Msg1 for the A-IoT device)

[0287] T R2D_R2D_min: Minimum time between two different consecutive R2D transmissions to the same A-IoT device

[0288] T D2R_D2R_min : Minimum time between two different consecutive D2R transmissions from the same A-IoT device

[0289] For the time interval between an R2D transmission and the corresponding D2R transmission following it, there are two options studied.

[0290] Option 1: Maximum time T between the R2D transmission and the D2R transmission corresponding to the R2D transmission R2D_max can be defined, and the device transmits D2R [T R2D_min Can be performed within the interval [ , TR2D_max] (Define a maximum time T R2D_max between a R2D transmission and the corresponding D2R transmission following it, so that the device transmits D2R transmission within [T R2D_min , T R2D_max ]).

[0291] Option 2: D2R transmission timing (T) corresponding to the R2D transmission following the R2D transmission R2D) can be determined based on control information within the R2D transmission. In this case, T R2D ≥ T R2D_min The condition can be satisfied (The corresponding D2R transmission timing T R2D Following a R2D transmission is determined based on the control information in the R2D transmission, where T R2D ≥ T R2D_min) .

[0292]

[0293] T1 and T2 in Table 4 are parameters defined in UHF RFID, and their minimum / maximum values ​​can be determined by RTcal, Tpri, and FrT. T1 may be a time interval parameter between R2D transmission and the D2R transmission of the response message corresponding to R2D transmission. T2 may be a time interval parameter between D2R transmission and the R2D transmission of the response message corresponding to D2R transmission.

[0294] Tpri is the backscatter-link pulse-repetition interval, and TRcal may be the tag-to-interrogator calibration symbol. DR (Divide Ratio) is a value related to the data transmission rate and can be 8 or 64 / 3. A DR of 8 may imply a lower data transmission rate than a DR of 64 / 3. Tpri and TRcal can be determined based on BLF, for example, through the following formula.

[0295] BLF = 1 / Tpri = DR / TRcal

[0296] Therefore, when different BLFs are used in frequency domain resources, the setting of timing relationship parameters needs to be defined. Timing relationship parameters can be determined based on the BLF values ​​of each frequency. For example, timing relationship parameters can be determined based on a single common BLF, and minimum BLF values, intermediate BLF values, maximum BLF values, average BLF values, etc., may be used.

[0297] FIG. 34 is a diagram showing a time-domain resource allocation structure for transmitting PDRCH according to one embodiment of the present specification.

[0298] Devices that have received a paging message from a reader can send a response message to the paging message using PDRCH.

[0299] Referring to FIG. 34(a), there may be one time domain resource, and the device may have one opportunity to transmit PDRCH after receiving a paging message. In this case, if there are multiple devices for the paging message, each device may determine whether to respond to the paging message based on a randomly selected random number. If the randomly selected random number is 3, the device may decrease the random number by 1 after receiving each paging message, and transmit a response message to the paging message when it becomes 0 or 1.

[0300] Referring to FIG. 34(b), the time domain resource may be greater than 1, and the device may have at least two opportunities to transmit PDRCH after receiving the paging message. The paging message transmitted by the reader may include an indicator X that indicates the number of time domain resources. The number of time domain resources used in the inventory process can be indicated using the indicator X. The indicator X may be different for each inventory. For example, referring to FIG. 34(b), the time domain resource may be set to be greater than 1 for each inventory round, and the time domain resources for each inventory may be allocated as three or two. Within a certain time from the point of receiving the paging message, the transmission of MSg-1 from the first of the multiple time domain resources may begin. The length of the first resource may be determined based on the data rate, information bits, number of repetitions, etc. After a certain time from the point of ending the transmission based on the first resource, the transmission based on the next resource may begin. A certain time interval may be required between the last transmission time on the first resource and the first transmission time on the second resource. This certain time interval can be determined by considering the SFO. Resources in the additional time domain can be expanded using the same method described above to determine their transmission times. In this case, resource usage may be determined based on the device's performance. Devices designed for ultra-low power consumption may lack a time counting function. The time counting function may be a feature that distinguishes multiple time domain resources within the time domain to allow the use of the corresponding time domain resource at a specific time. Resources must be used within a pre-planned time domain to ensure they do not overlap with other resources in the time domain. Therefore, a device without a time counting function [transmits] a PDRCH transmission from the first time domain resource after receiving a paging message.R2DMax It can be executed within. The start of the second time-domain resource is T R2DMax This can be done at the following time point. Additionally, a device with a time counting function may be configured to use the second time-domain resource or the first time-domain resource. That is, when the number of time / frequency resources indicated in the paging message is X, devices without a time counting function or with a large SFO can respond from the first time resource, while devices with a time counting function and a small SFO can respond from all time resources or from the X-1 time resource excluding the first time resource. In this case, devices capable of responding from the first resource can perform random access by decreasing a random number by 1 based on each P-paging message as shown in Fig. 34(a) (regardless of X), and devices capable of responding from all resources can respond to the paging message at the time when the random number becomes 0 or 1 by decreasing the random number by the number of resources they can transmit (X or X-1). At this time, the device may randomly select a resource again from X or X-1 resources to send a response message to the paging message, or send a response message to the paging message in a slot where its own random number becomes 0.

[0301] FIG. 35 shows an allocation structure of time domain resources for transmitting PDRCH according to one embodiment of the present specification.

[0302] FIG. 35 illustrates a method for dynamically assigning time resources by extending the time domain resource allocation method described with reference to FIG. 34. For each inventory round, time domain resources can be configured as one or a number greater than one. Referring to FIG. 35, time domain resources can be configured in the form of three, one, or two for each inventory round. Time domain resources may be fixed or adaptively configured. The number of time domain resources can be indicated via an indicator X, and timing-related information can be extended and applied using predefined values. In this case, devices that cannot time count may send Msg-1 in response only to paging messages indicated by X=1. Devices capable of time counting may send Msg-1 in response only to paging messages indicated by X>1.

[0303] FIG. 36 is a diagram of another embodiment showing a time-domain resource allocation structure for transmitting PDRCH according to one embodiment of the present specification.

[0304] Referring to FIG. 36, time domain resources can be configured as one or a number greater than one for each inventory round. The number of time domain resources can be indicated by indicator X, and timing-related information can be extended to a predefined value.

[0305] For devices with a time-counting function, the reader can indicate the respective starting position for X time-domain resources. For example, the reader can individually indicate the starting point of each resource based on the time of the last transmission of a paging message. Or the reader T R2D_min The start time of each time domain resource can be indicated based on the value. The start time of each resource may be a time point that takes into account the transmission time of the time domain resource and the time gap between each time domain resource, taking into account the device's SFO.

[0306] For devices without a time counting function, use the first time domain resource among X time domain resources to T R2D_min A response message to a paging message can be transmitted within TR2D_max_wo_TimeCounting. The reader can indicate the start time for time-domain resources after the second resource. The reader indicates the last transmission time of the paging message, T R2D_min , based on the TR2D_max_wo_TimeCounting value, time information of subsequent time resources can be provided.

[0307] For devices with a time counting function, T R2D_max ...may not be considered. If the reader calculates the interval of the time resource based on the X resource information indicated in the paging message and does not receive PDRCH at the set time, the reader may determine that PDRCH was not transmitted and proceed with the subsequent process.

[0308] Time-domain timing variables can be configured by considering the device's BLF, small frequency shift, chip duration, and data rate. For the sake of convenience, a method for configuring time-domain timing variables using BLF is described; however, time-domain timing variables can be configured by considering at least one of the small frequency shift, chip duration, and data rate. When a device transmits a PDRCH using multiple time resources, if the BLF values ​​of each time resource are different, the position of the time resource may be set based on the smallest BLF value. The device may obtain the BLF value for a time-domain resource within a paging message, and the device may set timing variables based on the obtained information. Alternatively, timing variables may be defined as pre-configured values ​​considering the maximum value, average value, different BLFs, and chip durations.

[0309] FIG. 37 is a diagram illustrating a method for allocating a plurality of time domain resources and a plurality of frequency domain resources according to one embodiment of the present specification.

[0310] Figure 37 illustrates a configuration of a pre-set number of time domain resources and frequency domain resources. Referring to Figure 37, a device without a time counting function can transmit a message by using one of multiple frequency domain resources from the first time domain resource. Devices with a large SFO may preferentially use time domain resources (e.g., the 1st and 2nd slots) that are close to the paging message. For a device with a large SFO, if Y slots out of a total of X slots are available for transmission considering the SFO capability, random access can be performed by subtracting a random number by Y. Even within multiple frequency domain resources within a single time domain resource, BLF values ​​may differ. In this case as well, timing-related variables can be set using the minimum BLF. Timing-related variables can be defined as pre-set values ​​considering the maximum value, median value, average value, and BLFs.

[0311] FIG. 38 is a diagram illustrating a method in which a plurality of time domain resources and a plurality of frequency domain resources are adaptively allocated according to one embodiment of the present specification.

[0312] FIG. 38 shows that the configuration of time domain resources and frequency domain resources is adaptively directed for each inventory round. Inventory #N-1 may be composed of 2 time domain resources and 4 frequency domain resources, Inventory #N may be composed of 2 time domain resources and 1 frequency domain resource, and Inventory #N+1 may be composed of 1 time domain resource and 4 frequency domain resources. Referring to FIG. 38, a device without a time counting function transmits a message (Msg-1) from the first time resource, and when a reader transmits Msg-2, which is a response message to Msg-1, the device transmits Msg-2 from the first time resource of the time resources allocated to enable transmission of Msg-2.

[0313] FIG. 39 is a diagram showing the relationship between DSB and SSB in frequency domain resource allocation according to one embodiment of the present specification.

[0314] Referring to FIG. 39, PDRCH messages transmitted by devices in response to a reader's PRDCH message can be transmitted simultaneously using the FDMA method by utilizing SFS (Small Frequency Shift). In this case, if the transmission frequency band allocated to each device is DSB, the devices can transmit messages using both frequency domains based on the carrier frequency indicated by Fc (see FIG. 39(a)). SFS occurs by a frequency shift (FS) value based on Fc, and FS can be equal to 1 / (2*chip_length). chip_length can be 2 / (Btx_D2R*M). Btx_D2R can be the transmission bandwidth available to the device. M can be the number of repetitions of the codeword in the line code. Devices can transmit the same signal to both sides, and the size of the transmission frequency resource is doubled, and the transmission power per frequency can be reduced by the increased size of the frequency resource.

[0315] When the transmission frequency band of each device is SSB, each device can transmit a message using one frequency range relative to Fc (see Fig. 39(b)). In this case, additional filtering may be required to remove the signal from the other side. The right region (higher frequency relative to Fc) or the left region (lower frequency relative to Fc) relative to Fc may be used. SFS may occur as much as FS relative to Fc, and since SSB uses only one frequency resource compared to DSB, the frequency resource size can be halved, and the transmission power per frequency can be increased by the amount of the reduced frequency resource size.

[0316] FIG. 40 is a diagram illustrating a method for allocating frequency domain resources according to one embodiment of the present specification.

[0317] Devices performing simultaneous transmission of FDMA-based PDRCH messages can be classified according to their capabilities into devices capable only of DSB, devices capable only of SSB, or devices capable of both DSB and SSB-based transmission. Devices for ultra-low power consumption may not have additional filters for operating SSB and may operate only via DSB. Referring to FIG. 40, Device #1 may be used for Fs0, Device #2 which supports only DSB may be used for Fc+ / -Fs1, and Device #3 which supports SSB may be used for Fc+Fs1 or Fc-Fs1. Device #4 which supports SSB may be used for Fc+Fs2. The frequency domain resources used by SSB may be resources on either the right or left side relative to Fc. For example, a device that supports SSB may use frequency domain resources on the right side relative to Fc. The device may use frequency resources in the manner described above when transmitting Msg-1 and Msg-3. The device may indicate to the reader whether SSB operation is possible when transmitting Msg-1. The reader may consider whether SSB operation is possible when allocating frequencies for subsequent uplink message transmission. The reader may indicate the location of frequency domain resources where SSB is possible based on Fc. Alternatively, the device may inform the reader whether both DSB and SSB are supported. Referring to FIG. 40, the paging message may include information indicating FDMA resources, and the information indicating FDMA resources may indicate 6, which is the total number of transmittable SSB resources. Since a device supporting DSB must occupy 2 SSB resources, it can arbitrarily select and transmit one of a total of 3 frequency resources such as (1, 6), (2, 5), and (3, 4). Since a device supporting SSB occupies 1 resource, it can arbitrarily select and transmit one of a total of 6 frequency resources such as (1, 2, 3, 4, 5, 6).For example, if an SSB device D#3 transmits to resource (5), which is part of resource (2,5) transmitted by a DSB device D#2, the signals may be received redundantly. In this case, the DSB device can receive D#2's signal through resource (2) without collision, but D#3's signal may not be received due to a collision at resource (5).

[0318] FIG. 41 is a diagram showing the structure of a preamble preceding a PRDCH according to one embodiment of the present specification.

[0319] The reader may transmit a preamble prior to transmitting the PRDCH. The preamble may consist of a start indicator part and a time acquisition part. The start indicator part may include a signal with a special pattern indicating that the signal transmitted from the reader has started. This may not be necessary if the device expects to receive a signal from the reader. The time acquisition part may include information for synchronizing the frequency phase for the device to receive the PRDCH. In the time acquisition part, since the PRDCH signal is transmitted in the form of OOK (On-off Keying), a predefined OOK signal pattern may be transmitted to receive the device's PRDCH. The device that transmitted the PRDCH may expect a response signal from the reader within a certain time interval, and the response signal may be the Preamble + PRDCH signal. Referring to Fig. 41, T D2R_min can be from the last transmission time of PDRCH to the start time of the time acquisition part of PRDCH. The device is T D2R_minAfter the value, reception can begin from the time acquisition part to receive the PRDCH. Since the device that transmitted the PDRCH expects a response message to be transmitted within a certain time interval, it can receive the reader's response message even without receiving the start indicator part. Therefore, when the reader sends a response message to the device that transmitted the PDRCH, it may transmit only the time acquisition part and the PDRCH, excluding the start indicator part (see FIG. 41(b)). In this case, the structure of the PRDCH preamble when first transmitting a message with multiple devices as recipients, such as a paging message, and the PRDCH preamble when transmitting a response message to the device's PDRCH may differ from each other as shown in FIG. 41(a) and (b). This means that a device that has not transmitted a PDRCH (or a device that does not expect to receive a PRDCH within a specific time) will not recognize the message received from the reader as a signal addressed to the device if the message composition lacks a start indicator part, and may enter sleep mode, charging mode, or an OFF state to save power. If Msg-1 is transmitted using multiple time and frequency domains according to TDMA / FDMA, a time delay may occur until the device receives a PRDCH containing Msg-2, which is the response message to Msg-1. In this case, the reader may transmit a preamble containing a start indicator part and a PRDCH. The device that transmitted the PDRCH may know that a preamble containing a start indicator part and a PRDCH have been received after a certain period of time has elapsed while waiting for a response message to the PDRCH from the reader. In one-to-one communication between the reader and the device, that is, when the device recognizes or waits for a signal from the reader within any given time, the reader can transmit the preamble and PRDCH, excluding the start indicator part.The device can reduce the burden of receiving and decoding preambles that unnecessarily start from the start indicator part for messages that are not intended for it, and can save power by entering sleep mode, charging mode, or OFF state.

[0320] The structure of the start indicator part of the PRDCH responding to the PDRCH may be different in form (structure) from the start indicator part of the PRDCH preamble that triggers the paging message. If the device receives only the start indicator part of the PRDCH preamble transmitted after the paging message and it differs from the expected start indicator part of the PRDCH in the paging message, the device may enter sleep mode, charging mode, or an OFF state to save power. Alternatively, the structure of the preamble containing the start indicator part and the time acquisition part may differ from that of the PRDCH preamble of the paging message. Depending on the structure of the PRDCH preamble received after the paging message, the device may enter sleep mode, charging mode, or an OFF state to save power. A difference in the form (structure) of the preamble may mean that the ON / OFF pattern is different or that the sequence / code used is different.

[0321] FIG. 42 is a diagram showing the time relationship for message transmission within an inventory process according to one embodiment of the present specification.

[0322] The inventory can be divided into two stages.

[0323] Step 1: Inventory only process

[0324] - Step 1-1: The reader can send a paging message (Msg-0) to the device.

[0325] - Step 1-2: In response to a paging message, the device may send Msg-1 to the reader. Msg-1 may contain information that can identify the device. The information may include a random number of a certain length or a device ID.

[0326] Step 2: Inventory + command process

[0327] - Step 2-1: The reader can send a paging message (Msg-0) to the device.

[0328] - Step 2-2: In response to a paging message, the device may send Msg-1 to the reader. Msg-1 may contain information that can identify the device. The information may include a random number of a certain length or a device ID.

[0329] Step 2-3: The reader can send Msg-2 to the device in response to Msg-1.

[0330] Step 2-4: The device can send Msg-3 to the reader in response to Msg-2.

[0331] Msg-1 and Msg-3 are messages transmitted by the device to the reader and can be transmitted over a resource allocated as a time domain resource(s), a frequency domain resource(s), or a combination of both time and frequency domain(s). For example, referring to FIG. 42, Msg-1 and Msg-3 can be transmitted over multiple time domain resources. Additionally, Msg-1 and Msg-3 can be transmitted from a single time domain resource over multiple frequency domain resources. Additionally, Msg-1 and Msg-3 can be transmitted from multiple time domain resources over multiple frequency domain resources.

[0332] Msg-0 and Msg-2 are messages transmitted by the reader to the device, and Msg-0 can be transmitted as a single message by default. Msg-2 is a message transmitted by the reader to the device in response to Msg1. The method for transmitting Msg-0 and Msg-2 is described below.

[0333] Multiple response message fields can exist within a single PRDCH. A device receiving the PRDCH can check if there is corresponding information among the multiple response message fields.

[0334] Second, response messages for each device can be transmitted individually using each PRDCH. Referring to FIG. 42, each PRDCH can be transmitted over multiple time-domain resources.

[0335] Resource allocation for transmitting messages can be defined in the time domain, and depending on the definition, the reader and the device can perform an inventory process.

[0336] The device may contain an SFO of 10^4 to 10^5 ppm. The unit of ppm used in this invention refers to part(s) per million and can represent one-millionth. The SFO value may vary depending on the type of device. Considering the SFO and processing time, there may be a certain time interval between each message. The time relationship in Fig. 42 may be a relationship between devices that have a time counting function. T2, T4, T6, T8, T10, and T12 may be values ​​that the device can calculate through the chip length, BLF, and TBS size.

[0337] - T1: The time interval between Msg-0 and the first Msg-1, where T R2D_min It can be set to a value larger than.

[0338] T3 and T11: Time intervals between time domain resources where Msg-1 is transmitted, which can be configured so that time resources T2 and T4 do not overlap by considering the SFO of each device.

[0339] - T5: The time interval between the time of transmission of the last Msg-1 and the time of reception of Msg-2, where T D2R_min It can be set to a value equal to or greater than or greater than.

[0340] - T7: This may be the time interval between time-domain resources sent by the reader. T7 may be set based on the time interval required for the SFO and devices to be ready to receive consecutive Msg-2s.

[0341] - T9: The time interval between the time domain resources where the last Msg-2 and the first Msg-3 are transmitted, T R2D_min It can be set to a value equal to or greater than the value, or a larger value.

[0342] As shown in Fig. 42, when Msg-2 is included in multiple response messages and transmitted in a single PRDCH, the time intervals of T6, T7, and T8 can be replaced with the transmission time of Msg-2.

[0343] FIG. 43 is a diagram illustrating a method for setting a time domain variable based on whether a time counting function exists in a device according to one embodiment of the present specification.

[0344] For a device without a time counting function, time relationship setting variables when using a conventional single time domain resource may be applied. Referring to FIG. 43, even if multiple time domain resources are available for Msg-1, Msg-2, and Msg-3, a device without a time counting function can transmit messages using the very first or a pre-set location.

[0345] Msg1_A is T R2D_min_AIt can be transmitted over time domain resources between and TR2D_max_wo_TimeCounting_A. Msg1_B can be transmitted over time domain resources after TR2D_max_wo_TimeCounting_A + T2 (transmission time of Msg1_A) + T3 (time interval between Msg1s). The resources for Msg1_A and Msg3_A may be time / frequency domain resources for devices without time counting capabilities. The resources for Msg2_A may be time / frequency domain resources used by the reader for devices without time counting capabilities.

[0346] The first Msg2_A can be transmitted from a time-domain resource after T5 at the time when the reception of Msg1_B is completed. T of the device that sent Msg1_A D2R_min can be set to a value greater than or equal to T3+T4, or a value greater than T. D2R_max can be the value of T3+T4+T5.

[0347] The time interval required for the device that sent Msg2_A to receive Msg3 transmitted from the reader is T R2D_min It could be. R2D_min It can be set to a value equal to or greater than T7+T8 or greater.

[0348] T R2D_max can be the value of T7+T8+T9.

[0349] A single PRDCH in which Msg2 is transmitted may contain multiple response messages. If multiple response messages are delivered as a single message, the time interval between Msg2 and Msg3_A may be the conventional TR2D_min and TR2D_max values.

[0350] FIG. 44 is a diagram illustrating a method of configuring FDMA by transmission bandwidth using SFS according to one embodiment of the present specification.

[0351] The amount of SFS can be derived as (1 / (2* chip_length))*(1+ / -SFO). If SFO is not considered, the amount of SFS can be 1 / (2* chip_length). Alternatively, the amount of SFS can be + / - R / Tb Hz, where Tb is the time interval / transmission time corresponding to the bit after FEC (Forward Error Correction). The value of R can be R = Tb / (2xD2R_chip_length). chip_length can be derived using the line code repetition number, square wave frequency value, OOK modulation, or BPSK modulation (line code repetition number / square-wave frequency number / OOK modulation / BPSK modulation (M or R)) for chip_length_ref corresponding to Btx_D2R. chip_length can be chip_length_ref / M. Or chip_length can be chip_length_ref / R. D2R_chip_length may be equal to chip_length. chip_length may be a value corresponding to 2, 4, 8, 16, 32, and 128 in FIG. 44(a). The value of R may increase as the chip length decreases. FIG. 44(a) shows the chip_length value according to the value of M for each DSB Tx bandwidth (BW) (KHz) and the number of possible FDMs for each BW. In FIG. 44(a), the value of M used is exemplified by using 7 values ​​{2, 4, 8, 16, 24, 32, 64}, but it is not limited to 7. The chip_length value may vary depending on the value of M. Therefore, the value of M may be limited up to a value that maintains a chip_length greater than twice the sampling clock period. The sampling clock may be 1.92 MHz or 2.4 MHz, and the sample period corresponding to the sampling clock may be 0.528 µs and 0.416 µs.The maximum value of M that maintains the minimum chip_length value satisfying the Nyquist theorem can be determined by the maximum value of the sampling clock, and the number of M values ​​that can be used can be determined. Referring to Fig. 44(a), the number of possible FDM values ​​per BW can be derived. The number of possible FDM values ​​per sampling clock can be derived. Fig. 44(b) shows the relationship between chip_length_ref and the data rate for each BW. The BW can be determined by considering SSB and DSB. The data rate can be derived by considering whether line coding and Forward Error Correction (FEC) are applied. In Fig. 44(a), a relatively low data rate is supported in the BW where FDM is supported, and a relatively high data rate is supported in the BW where FDM is not supported. Therefore, FDM and / or TDM can be supported in Msg1, which transmits relatively little information during the inventory process. In Msg3, which transmits more information than Msg1, TDM can be supported because a BW that supports a high data rate is used. Based on FIG. 44(a), the reader may instruct the device to set a pre-configured SSB / DSB Tx BW (Btx_D2R), a list of M values, or the number of available M values. If a K value indicating the number of available M values ​​is determined, M can be derived as M=2^n (where n increases by 1 from 1 to K). Alternatively, the maximum number of M values ​​that can be used for each BW is defined and can be used without separate signaling. The BW allocation information may be instructed differently for groups capable of FDM and groups that cannot (or do not configure FDM).

[0352] FIG. 45 is a diagram showing the time relationship for a device to monitor Msg2 according to one embodiment of the present specification.

[0353] There may be multiple Msg1s transmitted by the device. Accordingly, there may also be multiple Msg2s, which are response messages corresponding to the multiple Msg1s. Each Msg2 may be transmitted via its respective PRDCH, and multiple Msg2s may be transmitted via a single PRDCH. Referring to FIG. 45, the reader may transmit Msg2 using its respective PRDCH. The device that transmitted Msg1 can expect Msg2 to be received within a set time interval. In a situation where there is no SFO and the timer for scheduling operates correctly, all devices can start monitoring at time e in FIG. 45 and wait for reception within the pre-configured time interval for the PRDCH. If an SFO is taken into account, a buffer time corresponding to the SFO may be added in addition to the actual message transmission time. The reception time of Msg2 may not occur at time e in FIG. 45. Therefore, the device may monitor Msg2 considering a set time interval around time e. For example, the device T D2R_min_A Start monitoring at T D2R_max_A If Msg2 is not received after continuing monitoring until [date], it is determined that reception failed or Msg1 transmission failed, and the next inventory and / or random access procedure can be performed. If the device successfully receives Msg2, the device can transmit Msg3 to the reader. If the monitoring start time for Msg2 is common, the monitoring time interval for Msg2 is T as g in Fig. 45, considering the SFO. D2R_max -T D2R_min It may be. Alternatively, if the response messages of Msg2 arrive in a pre-configured order, it may receive only the Msg2 for itself at that point. In this case, the Msg2 monitoring time interval for the individual device is T D2R_max_A - T D2R_min_A , T D2R_max_B - T D2R_min_B It can be. In this case, T D2R_max_X, T D2R_min_X can be defined as a separate value for each individual device (or corresponding time domain resource), and the start time may vary depending on the method of determining the reference time for Msg2 monitoring. The start time of receiving Msg2 may be a common time or may vary for each individual device.

[0354] In addition, the reference time points for inducing the start time for monitoring Msg2 can be considered as methods from a to d in Fig. 45.

[0355] a in FIG. 45 may represent the last transmission time of a paging message that triggers random access. b may represent the last transmission time of a message for a D2R trigger following the paging message. c may represent the last transmission time of Msg1 transmission of an individual device. d may represent the last transmission time of a time domain resource allocated for Msg1 transmission.

[0356] Although the reference points a through d in FIG. 45 are described as the respective last transmission / reception points, they may also be the respective start points or the end / start points of already planned time domain resources. This concept can be extended and applied to the content of the invention thereafter.

[0357] The following describes the combination of conditions for the start time of monitoring Msg2 and the conditions for the reference time to induce the monitoring start time.

[0358] FIG. 46 is a diagram showing the start time of monitoring of individual Msg2 among the time relationships for monitoring Msg2 according to one embodiment of the present specification.

[0359] The device may use two time-domain resources and multiple frequency-domain resources. The starting point for monitoring Msg2 may differ, as shown in Fig. 46c and Fig. 46d. This can be efficient when the device that transmitted Msg1 knows the transmission time of Msg2 being transmitted to it. Alternatively, the reference point for deriving each Msg2 transmission time may be based on the last time of Msg1 transmission by the individual device. The time relationship shown in Fig. 46c and Fig. 46a can be derived from the relationship between Msg1_A and Msg2_A, and the device that transmitted Msg1_A can start monitoring Msg2_A at the derived time interval, and the time variable for deriving the time relationship is T D2R_min_A It may be. From the relationship between Msg1_B and Msg2_B, the time relationship shown in Fig. 46 d and Fig. 46 b can be derived, and the device that transmitted Msg1_B can start monitoring Msg2_B at the derived time interval, and the time variable for deriving the time relationship is T D2R_min_B It could be.

[0360] FIG. 47 is a diagram showing the individual start time of Msg2 monitoring among the time relationships for Msg2 monitoring according to one embodiment of the present specification.

[0361] The device may use two time domain resources and multiple frequency domain resources. The start time for monitoring Msg2 may be Fig. 47 b and Fig. 47 c. Devices that transmitted Msg1 may start monitoring Msg2 from the time points of Fig. 47 b and Fig. 47 c, respectively. The reference time point for inducing the start time points of Msg2 monitoring, Fig. 47 b and Fig. 47 c, may be the time point of the time domain resource allocated for transmitting Msg1, as in Fig. 47 a.

[0362] FIG. 48 is a diagram showing the common start time of Msg2 monitoring among the time relationships for Msg2 monitoring according to one embodiment of the present specification.

[0363] The device may use two time domain resources and multiple frequency domain resources. The starting point for monitoring Msg2 may be c in FIG. 48. Devices that transmitted Msg1 may start monitoring Msg2 from time c in FIG. 48. The reference point for inducing c in FIG. 48, which is the starting point for monitoring Msg2, may be the last time point at which an individual Msg1 was sent, as in e in FIG. 48, or the last time point of the time domain resource allocated for transmitting Msg1, as in f in FIG. 48.

[0364] FIG. 49 is a diagram showing a common start time for Msg2 monitoring including a plurality of responses among the time relationships for monitoring Msg2 of a device according to one embodiment of the present specification.

[0365] Since the devices that sent Msg1 only need to receive one PRDCH, the start time for Msg2 monitoring can be a single one, as shown in e of Fig. 49. Each device that sent Msg1 can determine a reference / start time to trigger the Msg2 monitoring time. The reference / start time may be the last / start time when each Msg1 was sent, as shown in a of Fig. 49. Alternatively, the reference / start time may be the last / start time when the D2R trigger message was received. The D2R trigger message may be an R2D message sent after the paging message and may contain additional information for D2R transmission. Alternatively, the reference / start time may be the last / start time when the paging message was received.

[0366] FIG. 50 is a diagram showing the relationship between the start time of Msg2 monitoring, the paging message, and the R2D trigger message among the time relationships for Msg2 monitoring according to one embodiment of the present specification.

[0367] Figure 50a may be a common time point that is commonly set for the devices as the start time of Msg2. The reference time point for inducing the common time point may be determined based on the last / start transmission time of the R2D trigger message.

[0368] Figure 50b is the start time for monitoring Msg2, which can be set differently for each device. The reference / standard time for inducing the start times can be determined based on the last / start transmission time of the R2D trigger message.

[0369] c of FIG. 50 may be a monitoring start time for monitoring Msg2 and may be set commonly for devices. A reference point / standard time for inducing the start time may be determined based on the last / start transmission time of the paging message.

[0370] d in Fig. 50 is a start time for monitoring Msg2, which can be set differently for each device. The reference / standard time for inducing the start times can be determined based on the last / start transmission time of the paging message.

[0371] FIG. 51 is a diagram showing a time point based on the transmission of Msg2 and Msg3 among the time relationships for monitoring Msg2 according to one embodiment of the present specification.

[0372] Referring to FIG. 51, for devices that have transmitted Msg1, the device receives Msg2 from the reader and can immediately transmit Msg3 to the reader. Then, the device receives Msg2 for the next device and transmits Msg3. Therefore, the time interval for receiving each Msg2 can be wider. In this case as well, the method described through FIG. 45 can be applied.

[0373] a of FIG. 51 can be commonly set for the devices as the monitoring start time of Msg2. The reference point for inducing the start time can be determined based on the last / start transmission time of the time domain resource allocated for the transmission of Msg 1. Devices waiting for a response after transmitting Msg 1 can wait for Msg2 to be transmitted to the device from the monitoring time.

[0374] Figure 51b represents the monitoring start time of Msg2, which can be set differently for each device. The reference point for inducing the start time can be determined based on the last / start transmission time of the time domain resource allocated for the transmission of Msg 1. Devices waiting for a response after transmitting Msg 1 may wait for Msg2 to be transmitted to the device from the individual monitoring time. In this case, the order or timing of receiving Msg2 may be pre-set.

[0375] c of FIG. 51 can be commonly set for the devices as the monitoring start time of Msg2. The reference point for inducing the start time can be the last / start time of transmitting Msg1 of the individual device.

[0376] d in Fig. 51 is the monitoring start time of Msg2, which can be set differently for each device. The reference point for inducing the start time can be the last / start time when Msg1 was transmitted.

[0377] e in Fig. 51 can be commonly set to the devices as the monitoring start time of Msg2. The reference / standard time to induce the start time can be determined based on the last / start time when the R2D trigger message was received.

[0378] f in Fig. 51 is the monitoring start time of Msg2, which can be set differently for each device. The reference point / standard time to induce the start time can be determined based on the last / start time when the R2D trigger message was received.

[0379] g in Fig. 51 can be commonly set to the devices as the monitoring start time of Msg2. The reference point / standard time to induce the start time may be the last / start time when the paging message was received.

[0380] h in Fig. 51 is the monitoring start time of Msg2, which can be set differently for each device. The reference point / standard time to induce the start time may be the last / start time when the paging message was received.

[0381] FIGS. 52 and 53 are drawings illustrating an FDMA method considering SFS according to one embodiment of the present specification.

[0382] Referring to Fig. 44, the number of possible FDMs can be calculated by applying SFS for each Btx_D2R. When SFS is applied, the chip length can be reduced by 1 / M or 1 / R depending on the SFS factor M (or R). As the value of R increases, the chip length can be reduced proportionally. That is, referring to Fig. 45, the transmission time required to transmit the same data can be reduced proportionally when R is 2, 4, or 6 compared to when R is 1. D2R transmission may consist of a preamble and a PDRCH structure. The preamble may be configured in various forms, and the preamble length may also vary. For convenience of explanation, this specification assumes that the preamble is in the form of a binary sequence and has a length of 32 bits. The binary sequence may be an M-sequence or a Golay sequence. Alternatively, a pre-configured pattern consisting of on / off may be used instead of a binary sequence.

[0383] Referring to FIG. 53, a D2R transmission can be composed of a combination of a preamble, PDRCH, and midamble. A postamble may also be included in the D2R transmission. The preamble and midamble may be composed of binary sequences or on / off patterns, and the lengths of the preamble and midamble may be the same or different from each other.

[0384] Figure 54 is a diagram illustrating a method for matching the same data rate from different frequency resources in an FDMA situation.

[0385] Figure 54(a) shows that the D2R transmission is composed of a preamble and a PDRCH structure. Referring to Figure 54(a), the chip length can be reduced by half when R=2 compared to when R=1. Consequently, the total D2R transmission (transmission of the preamble and PDRCH) time can also be reduced by half. When devices perform D2R transmission via FDMA, each device can use frequency domain resources with different R values. In this case, each device can apply repetitions of the mapping values ​​of OOK / BPSK modulation equal to the R value to maintain the same data rate. For example, if the device uses OOK modulation, 1 can be mapped to 01 and 0 can be chip-mapped to 10. In this case, if R=2, it is represented as 2R, and 1 can be repeated twice as 0101 and 0 can be repeated twice as 1010. For example, if BPSK modulation is used, 1 can be mapped to -1+1 and 0 can be chip-mapped to +1-1. In this case, if R=2, it is expressed as 2R, and 1 can be repeated twice as -1+1-1+1 and 0 can be repeated twice as +1-1+1-1. The chip length is reduced by half, but the number of repetitions increases, allowing the same transmission rate to be maintained for each frequency resource.

[0386] A binary sequence can be used for the D2R preamble, and line codes or non-line codes may be applied. If the Manchester code is applied among line codes, the preamble length of 32 bits can become 64 chips. For the sake of convenience, the length of the preamble can be expressed as the sequence length, and if a line code is applied to the preamble, the length can be doubled. Referring to Fig. 54(a), PDRCH_1R represents the case where the R value is 1 and PDRCH_2R represents the case where the R value is 2, indicating that OOK / BPSK modulation is applied and the mapping value is repeated twice. Maintaining the preamble in a sequence form can be effective for preserving correlation characteristics. If the R value is greater than 1, the following method may be applied to the preamble instead of the repetition method of the OOK / BPSK mapping value.

[0387] i) The preamble may be repeated in units of sequence length (5401). ii) A sequence that is extended by R times may be applied to the preamble (5404). iii) The preamble may not be repeated, and the PDRCH may be repeated and transmitted (5403). Alternatively, the preamble may not be configured to be repeated continuously, and the preamble may be configured to be repeated by R-1 times after the PDRCH, and vice versa. Alternatively, the preamble may be configured by R / 2 times before the PDRCH and the remainder after the PDRCH based on the value of R.

[0388] FIG. 54(b) shows that the D2R transmission consists of a preamble, PDRCH, and midamble structure. The midamble may be placed after the PDRCH. In the D2R transmission structure, excluding the PDRCH (e.g., preamble, midamble), the preamble repetition method described through FIG. 54(a) may be applied to the preamble and / or midamble where binary sequences are used or correlation properties are maintained. Line codes are applied to the preamble and midamble, but for convenience, they can be expressed as sequence lengths. 5411 in FIG. 54(b) represents the structure of the D2R transmission (preamble + PDRCH + midamble + PDRCH) when the R value is 1. In FDMA situations, to maintain the same data rate between devices using different R values, the PDRCH may be repeated as many times as the R value.

[0389] 5412 in Fig. 54(b) represents a structure in which the preamble and midamble are repeated by an R value of 2 in units of sequence length. 5413 in Fig. 54(b) represents a structure in which the preamble and midamble are not repeated, and only PDRCH is repeated. Alternatively, the repeated preamble and midamble may not be consecutive, and the preamble and midamble may be positioned separately after PDRCH. Alternatively, the preamble and midamble may not be repeated consecutively, and if the sequences of the preamble and midamble are different, the preamble may be repeated R times or the midamble may be repeated R times after PDRCH. Alternatively, the preamble and midamble may not be repeated consecutively, and the preamble and midamble may be configured to be repeated R-1 times after PDRCH, and the opposite case may also be possible. Alternatively, based on the R value, R / 2 times the preamble and midamble, respectively, may be repeated at their respective positions, and the remainder may be configured after the PDRCH. If the midamble is located at the end of the PDRCH, the repeated preamble and midamble may be located after the last midamble.

[0390] 5412 in Fig. 54(b) indicates that when the R value is 2, a sequence that is extended by R times (2 times) is applied. That is, the sequence length can be increased from 32 to 64.

[0391] The M sequence can be a binary sequence with the longest period that can be generated by an LFSR (Linear Feedback Shift Register).

[0392] The period of the sequence M is 2^n-1, where n is the register length (number of bits) of the LFSR. During one period, the number of 1s and 0s is nearly equal, but there can be one more 1. For example, if n=3, a feedback polynomial of x^3 + x + 1 can be constructed, and the initial value can be 1 0 0. The sequence M can possess the characteristics of maximum period, good autocorrelation, low cross-correlation, and randomness.

[0393] A Golay sequence can consist of two binary sequences A and B, and A and B can have the same length. The two sequences must satisfy the orthogonality condition; that is, A●B=0, and the inner product of the two sequences must be zero. Golay sequences can provide a high signal-to-noise ratio because the sum of their autocorrelation functions is equal to the delta function. The cross-correlation between different Golay sequences can be very low.

[0394] FIG. 55 is a diagram illustrating multiplexing and multiple access methods in the transmission of Msg 1 according to one embodiment of the present specification.

[0395] Msg1 can be transmitted using various transmission methods. As shown in FIG. 55a, Msg1 can be transmitted using the TDMA method. As shown in FIG. 55b, Msg1 can be transmitted using the FDMA method. As shown in FIG. 55c, Msg1 can be transmitted using a method combining TDMA and FDMA. In FIG. 55, for convenience of explanation, the number of resources in the time domain and the number of resources in the frequency domain are shown as 2 and 5, respectively, but are not limited thereto.

[0396] Msg2 is a response message to Msg1 and can be classified as follows depending on the transmission method. If response information for multiple Msg1s is included in a single PRDCH, Msg2 may be described as Common-Msg2, and if individual Msg2s are transmitted in correspondence with each Msg1, Msg2 may be described as Separate-Msg2.

[0397] Like Msg1, Msg3 can be transmitted in various ways, such as TDMA, FDMA, or a combination thereof.

[0398] FIG. 56 is a diagram showing the transmission method of Msg2 and Msg3 according to one embodiment of the present specification.

[0399] FIG. 56(a) illustrates an example of a Common-Msg2 structure. A Common-Msg2 may contain response information for multiple Msg1s within a single message. A Common-Msg2 may include identifier information corresponding to each Msg1 and resource allocation information for Msg3. The identifier information may be information related to the device. For example, the identifier information may include an AS ID (Autonomous System Identifier), a random number of length X bits, etc. X may be a positive integer. A reader may transmit identifier information corresponding to Msg1 to the devices, and each device may verify the identifier information to confirm that communication with the reader has been successful. A Common-Msg2 may also explicitly or implicitly indicate resource allocation information for Msg3. In FIG. 56(a), a Msg3 resource allocation structure composed solely of a Common-Msg2 and an FDMA method may be considered. In this case, in addition to device identifier information, a Common-Msg2 may include information of a certain bit length according to a defined format. The device can interpret information based on the format specified by Common-Msg2 and obtain resource allocation information. Additionally, the order of device-specific information fields can be used as a standard for mapping resource locations in Msg3, and the order can be distinguished for each device. Resource locations in Msg3 can also be mapped based on the order of device-specific information fields. Since Msg3 is limited to FDMA, mapping of frequency domain resources is possible, and since each frequency domain resource can be implemented using SFS, the SFS factor R value can be defined. Information related to time information can also use pre-configured information. Based on the order of device-specific information fields included in Common-Msg2, frequency domain resources allocated to the device transmitting Msg3 can be allocated in the following manner.

[0400] - Sequential Mapping Method: Based on the order of the device-specific information fields included in Common-Msg2, mapping / assignment can be performed in the form of f0 (R=2), f1 (R=4), f2 (R=8), f3 (R=16), and f4 (R=32), in order from smallest to largest R value. Alternatively, mapping / assignment can be performed sequentially from largest to smallest R value.

[0401] - Maximum Spacing Mapping Method: This may be a method of filling in resources starting from the furthest apart based on the order of the device-specific information fields included in Common-Msg2. In other words, R values ​​can be assigned in a form that is maximally spaced apart. For example, when there are 5 frequency domain resources and 2 device information items included in Msg2, the lowest and highest R values ​​can be mapped / assigned in the form of f0 and f4. Alternatively, if there are 3 device information items, they can be mapped / assigned in the order f0, f4, f2. Alternatively, if there are 4 device information items, they can be mapped / assigned in the order f0, f4, f2, f1 (or f3). Alternatively, if there are 5 device information items, they can be mapped / assigned in the order f0, f4, f2, f1, f3 (or f3, f1).

[0402] Referring to Fig. 56(b), Msg can be transmitted in a mixed manner of TDMA and FDMA. In this case, resources for transmitting Msg3 can be mapped / allocated in the following way according to the order of device-specific information fields.

[0403] - Method 1 (sequential mapping method): Based on the order of the device information fields of Msg2, it can be sequentially mapped / assigned in the form of f(0,0)~f(0,4) and f(1,0)~f(1,4).

[0404] - Method 2 (maximum spacing mapping method within the same time resource): Based on the order of the device information fields of Msg2, the R value in the first time domain resource is mapped / assigned in a maximum spacing form as in Fig. 56(a), and can be mapped / assigned in the same form in the second time domain resource.

[0405] - Method 3 (Resource Cross-Maximum Spacing Mapping Method 1): The criteria of the maximum spacing mapping method within resources at the same time are applied, but they can be mapped / assigned in order with the maximum spacing in the R value and time domain. For example, resources can be assigned in the order of f(0,0), f(0,4), f(1,0), f(1,4), f(0,2), f(1,2), etc. based on order.

[0406] - Method 4 (Resource Cross-Maximum Spacing Mapping Method 2): Resources can be allocated in the order of f(0,0), f(0,4), f(0,2), f(1,0), f(1,4), f(1,2), f(0,1), f(0,3), f(1,1), f(1,3) based on the order in Resource Cross-Maximum Spacing Mapping Method 1 (multiple combinations are possible for the above resources f(0,1), f(0,3), f(1,1), f(1,3)). It may be a method in which non-adjacent frequency resources within the same time resource are allocated first, and resources are allocated in the next time resource area in the same manner.

[0407] - Method 5: This may be a method for prioritizing the allocation of the most separated frequency resources among the unused frequency resources in the time resource domain based on Method 3. In this case, SFO may be considered. For example, f(0,0) and f(0,4) are used in the first slot, and in the second slot, f(1,1) and f(1,3) are used which are most separated without overlapping with the frequency resources used in the first slot, then f(0,2) is used again in the first slot, and then other resources are used.

[0408] Method 6: This may be a method for prioritizing the allocation of the most separated frequency resources among the unused frequency resources in the time resource domain based on Method 4. In this case, SFO may be considered. For example, f(0,0), f(0,4), and f(0,2) are used in the first slot, and in the second slot, f(1,1) and f(1,3) are used which are most separated without overlapping with the frequency resources used in the first slot, and then other resources are used.

[0409] Methods 5 and 6 are techniques configured to minimize collisions even when identical frequency resources in different time slots overlap due to SFO performance degradation of the devices by preferentially allocating non-identical frequency resources in different time slots.

[0410] FIG. 56(c) illustrates a structure in which multiple Separate-Msg2s are transmitted from a reader and Msg3s are transmitted from multiple frequency resources. Based on identifiers such as resource allocation indicators, message indexes, or message order indexes for the transmission of each Msg3 included in each Separate-Msg2, the methods described through FIG. 56(a) may be applied. For example, the resource allocation information included in Separate-Msg2 may be mapped to the frequency resource allocation method of Msg3. If the information related to resource allocation included in Separate-Msg2 is distinguished by an index, it may be mapped to frequency domain resources in low order / high order based on the index information, mapped in order from f0 to f4, or Method 1 or Method 2 of FIG. 56(a) may be applied considering the R value.

[0411] FIG. 56(d) shows a repeating form of FIG. 56(a). Referring to FIG. 56(d), if the structure of FIG. 56(a) is exceeded based on conditions of information fields that may be included in Common-Msg2 or the configuration form of resources of Msg1, Separate-Msg2 and Msg3 can be transmitted in the form of FIG. 56(d). The resource allocation for Msg1 is structured to support both TDMA and FDMA simultaneously, and the number of time domain resources and the number of frequency domain resources can be 2 and 5, respectively. FIG. 56(d) is configured such that frequency domain resources corresponding to Common-Msg2 are repeated for each time domain resource of Msg1, and the method applied in FIG. 56(a) can be applied to each.

[0412] FIG. 57 illustrates a method for transmitting Msg2 and Msg3 according to one embodiment of the present specification.

[0413] FIG. 57 illustrates resource allocation when there are an even number (e.g., 4) of frequency domain resources. Based on the order of the device-specific information fields included in Common-Msg2, the frequency domain resources allocated to the device transmitting Msg3 can be configured as follows.

[0414] - Method 1 (Sequential Mapping Method): Based on the order of device-specific information fields included in Common-Msg2, mapping / assignment can be performed in the form of f0 (R=2), f1 (R=4), f2 (R=8), f3 (R=16), in order from smallest R value to largest R value. Alternatively, mapping / assignment can be performed in order from largest R value to smallest R value.

[0415] - Method 2 (Maximum Spacing Mapping Method): This method may involve filling in frequency resources starting from the furthest apart based on the order of the device-specific information fields included in Common-Msg2. In other words, frequency resources can be allocated in a form where the R value is the maximum spacing. For example, when there are 4 frequency domain resources and 2 device information entries in Common-Msg2, the frequency domain resources can be mapped / assigned to the lowest and highest R values ​​in the form of f0 and f3. Alternatively, if there are 3 device information entries, the frequency domain resources can be allocated / mapped in the order of f0, f4, f1 (or f2). Or, if there are 4 device information entries, the frequency domain resources can be allocated / mapped in the order of f0, f3, f2, f1 (or f1, f2).

[0416] FIG. 57(b) shows the resources for transmitting Msg3 in a mixed TDMA and FDMA situation. Depending on the order of the device-specific information fields, the resources can be mapped / allocated in the following way.

[0417] - Method 1 (Sequential mapping method): Based on the order of the device information fields of Msg2, it can be sequentially mapped / assigned in the form of f(0,0)~f(0,3) and f(1,0)~f(1,3).

[0418] - Method 2 (maximum spacing mapping method within the same time resource): Based on the order of the device information fields of Msg2, the first time domain resource is mapped / assigned based on the maximum spacing R value in the same way as in Fig. 57(a), and the second time domain resource can also be mapped / assigned in the same way.

[0419] - Method 3 (Resource Cross-Maximum Spacing Mapping Method 1): The criteria of Method 2 are applied, but the resources can be mapped / assigned in order with the maximum spacing in the R value and time domain. For example, based on order, f(0,0), f(0,3), f(1,0), f(1,3) are assigned first, and the next resources f(0,2), f(1,2), f(0,1), f(1,1) can be assigned in various combinations.

[0420] - Method 4 (Resource Cross-Maximum Spacing Mapping Method 2): Based on the order in Method 3, resources can be allocated / mapped in the order of f(0,0), f(0,3), f(0,2), f(0,1) (or f(0,1), f(0,2)) followed by f(1,0), f(1,3), f(1,2), f(1,1) (or f(1,1), f(1,2)). This may be a method in which non-adjacent frequency resources within the same time resource are allocated first, and resources are allocated in the same manner in the next time resource region.

[0421] - Method 5: This may be a method for prioritizing the allocation of the most spaced frequency resources among the unused frequency resources in the previous time resource area based on Method 3. In this case, SFOs may be considered. For example, f(0,0) and f(0,3) are used in the first slot, and in the second slot, f(1,1) and f(1,2), which are the most spaced without overlapping with the corresponding frequency resources, are used, and then other resources may be used.

[0422] - Method 6: This may be a method based on Method 4 that prioritizes the allocation of the most spaced frequency resources among the unused frequency resources in the previous time resource area. In this case, SFOs may be considered. For example, f(0,0), f(0,3), and f(0,1) (or f(0,2)) may be used in the first slot, and in the second slot, f(1,2) (or f(1,1)) which is the most spaced without overlapping with the frequency resources used in the first slot may be used, and then other resources may be used.

[0423] Methods 5 and 6 are techniques configured to minimize collisions even when identical frequency resources in different time slots overlap due to SFO performance degradation of the devices by preferentially allocating non-identical frequency resources in different time slots.

[0424] FIG. 57(c) illustrates a structure in which multiple Separate-Msg2s are transmitted from a reader and Msg3s are transmitted from multiple frequency resources. Based on identifiers such as resource allocation indicators, message indices, or message sequence indices for the transmission of each Msg3 contained in each Separate-Msg2, the methods described through FIG. 57(a) may be applied. For example, information related to resource allocation contained in Separate-Msg2 may be mapped to the frequency resource allocation method of Msg3. If the information related to resource allocation contained in Separate-Msg2 is distinguished by an index, it may be mapped to frequency domain resources in order of lower / higher indices based on the index information, mapped sequentially from f0 to f3, or Method 1 or Method 2 of FIG. 57(a) may be applied considering the R value. Index information regarding the R value may be transmitted. For example, if there are 4 frequency domain resources and each frequency domain resource uses a different R value (e.g., 2, 4, 8 16), the relevant information can be indicated using 2 bits.

[0425] FIG. 57(d) shows a repeating form of FIG. 57(a). Referring to FIG. 57(d), if the structure of FIG. 57(a) is exceeded based on conditions of information fields that may be included in Common-Msg2 or the configuration form of resources of Msg1, Separate-Msg2 and Msg3 can be transmitted in the form of FIG. 57(d). The resource allocation for Msg1 is structured to support both TDMA and FDMA simultaneously, and the number of time domain resources and the number of frequency domain resources can be 2 and 5, respectively. FIG. 57(d) is configured such that frequency domain resources corresponding to Common-Msg2 are repeated for each time domain resource of Msg1, and the method applied in FIG. 57(a) can be applied to each.

[0426] FIG. 58 is a diagram showing the transmission relationship of individual Msg2 in a time domain resource and Msg3 in a frequency and time resource according to one embodiment of the present specification.

[0427] FIG. 58(a) shows a form in which the resources for Msg3 transmission described through FIG. 56(c) and FIG. 57(c) are extended into the time resource domain. Each individual Msg2 may explicitly or implicitly contain resource allocation information for Msg3. This may be mapping / allocation information for multiple time resources and multiple frequency domain resources within each time resource.

[0428] - Method 1: The reader provides time information for each Msg to which the corresponding Msg3 must be transmitted, and frequency domain resource allocation information may provide index information for the SFS factor R value. The index information may be provided in descending / ascending order of the R value or allocated in order of maximum separation. In this case, the time information may be the number of additional Msg2s transmitted after the corresponding Msg2 (A) and the order of the allocated slots in the entire Msg3 transmission time slot (B). Referring to FIG. 58(a), A may have a value of 0 to 9, and B may be 0 or 1.

[0429] - Method 2: The reader may provide time information (B) for Msg3 at the end of the time domain resources of Msg2, and frequency domain resource allocation information may provide index information for the SFS factor R. The index information may be indicated / mapped / assigned in descending or ascending order of the R value, or indicated / mapped / assigned in order of maximum separation. In this case, each device may receive Msg2 containing its own information and obtain time information (B) for Msg3, then continuously receive Msg2 until it receives the last Msg2 (where there is no further transmission of Msg2, or where the Msg2 contains an indicator indicating that it is the final Msg2), and then determine the transmission slot of Msg3 by applying the previously received time information (B) for Msg3 based on the last Msg2.

[0430] - Method 3: In a pre-configured method where Msg3 is allocated / indicated / mapped at regular time intervals based on the last transmission time of Msg2, Msg2 can indicate / map / allocate a combination of information regarding relative time positions and information regarding R values. In one embodiment, if there are two time interval resources, one of them can be indicated by a 1-bit indicator (B), and an additional bit for index information regarding R values ​​can be indicated. Alternatively, based on 1-bit time information, R values ​​can be mapped / allocated in descending or ascending order. At this time, each device recognizes the size of the entire time domain resource where Msg2 is transmitted and the end time (T_0), and then calculates its own Msg3 transmission slot using Msg3 transmission slot information (B).

[0431] Figure 58(b) shows that Msg2 and Msg3 are transmitted in a structure that is a repetition of Figures 56(c) and 57(c).

[0432] Figure 59 is a diagram showing the case where there is only one time resource in which Msg1 can be transmitted.

[0433] FIG. 59 shows the transmission relationship between the paging message, Msg2, and Msg3 when the number of time resources available to transmit Msg1 is 1. The transmission of Msg1 and Msg3 can be FDM.

[0434] FIG. 59(a) illustrates a method for transmitting Msg2 commonly (containing multiple response messages for Msg1 on a single PRDCH). offset1 It receives a paging signal that triggers random access, and the device can indicate / manifest when to transmit Msg1 to the reader. offset1 is defined as a nominal value, and based on the nominal value, the minimum and maximum times considering SFO can be calculated.

[0435] T below offset1 Explains the method for determining T. Determined Toffset1 The value can be specified by the reader or calculated by the device. Alternatively, the reader specifies a certain parameter, and the device calculates T based on the specified parameter. offset1 The value can be calculated.

[0436] - Method 1: T offset1 = max(A*chip_length R2D , B* chip_length D2R_R=1 )

[0437] A and B represent multiples and may be pre-fixed values ​​or values ​​indicated by the reader. A and B may be integers or rational numbers. If A and B are indicated by the reader, A and B may be included in an R2D message (e.g., Msg0). Or T offset1 Eun T offset1 This can be included in the R2D message immediately preceding the application. Alternatively, the reader may specify the final value selected within the applicable range for A and B. A and B can be the same or different values. chip_length R2D chip_length is the transmission chip length used by the reader for R2D transmission and can vary depending on the value of M. The value of M can be 2, 6, 12, or 24. Based on the length of one symbol, the chip length may decrease as the value of M increases. D2R_R=1 may be the chip length used by the device for D2R transmission. The chip length can be calculated based on the D2R transmission bandwidth when the R value is 1. The chip length can be calculated using the lowest minimum R value when FDM is used for D2R transmission. The chip length may be the chip length corresponding to the length required to transmit a bit. T offset1 is A*chip_length R2D and B* chip_length D2R_R=1 It can be determined as one of the values ​​(e.g., a larger value or a smaller value).

[0438] - Method 2: T offset1= A*chip_length R2D

[0439] T offset1 can be determined as a multiple of the chip length or bit length used for R2D transmission. The value of A can be a predetermined value or a value indicated by the reader. The method described in Method 1 can be used to indicate the value of A, or the final T to which the value of A is applied. offset1 The value can be indicated by the method described above.

[0440] - Method 3: T offset1 = B* chip_length D2R_R=1

[0441] T offset1 can be determined as a multiple of the chip length / bit length used for D2R transmission. The value of B may be a predetermined value or may be specified by the reader. The method of specification by the reader may be the same as Method 1. Or the final T with the value of B applied. offset1 The value can be indicated by the method described above.

[0442] The following explains how to set the timing and interval for monitoring Msg2.

[0443] - Method 1: Nominal value (T D2R_normal Decided as )

[0444] - C * chip_length R2D : It can be determined as a multiple of the chip length and / or bit length used for R2D transmission. The C value may be a fixed value or a value indicated by the reader. The method of indicating the C value is the T described above. offset1 It may be the same as the method of indicating A or B used in. The monitoring point is the last time Msg1 was transmitted or T offset1 It can be determined as the reference point.

[0445] - D * chip_length D2D_R=1: It can be determined as a multiple of the chip length and / or bit length used for D2R transmission. The D value may be a fixed value or a value indicated by the reader. The aforementioned T indicating the D value offset1 It may be the same as the method of indicating A or B used in. The monitoring point is the last time Msg1 was transmitted or T offset1 It can be determined as the reference point.

[0446] - Method 2: T D2R_min , T D2R_max

[0447] T D2R_min and T D2R_max The monitoring time point and interval of Msg2 can be determined based on the range of . That is, the monitoring interval is T D2R_min From T D2R_max It could be a section up to.

[0448] - T D2R_min = E * chip_length R2D , T D2R_max = F * chip_length R2D : T D2R_min can be determined as a multiple of the chip length and / or bit length used for R2D transmission. The values ​​of E and F may be fixed values ​​or values ​​indicated by the reader. The method of indicating the values ​​of E and F is the T described above. offset1 It may be the same as the method of indicating A or B used in. The monitoring point is the last time Msg1 was transmitted or T offset1 It can be determined as the reference point.

[0449] - T D2R_min = G * chip_length D2R_R=1 , T D2R_max = H * chip_length D2R_R=1 : It can be determined as a multiple of the chip length and / or bit length used for D2R transmission. The values ​​of G and H may be fixed values ​​or values ​​indicated by the reader. The method of indicating the values ​​of E and F is the T described above. offset1It may be the same as the method of indicating A or B used in. The monitoring point is the last time Msg1 was transmitted or T offset1 It can be determined as the reference point.

[0450] The time relationship between Msg2 and Msg3 is T used in Msg0 and Msg1 offset1 This can be utilized. In this case, A and B, representing the multiples, may be the same value or a newly specified value in Msg2. The chip length and / or bit length of Msg3 may also be changed to the value used in Msg2 or a new value specified by Msg2. T offset1 can be set based on the time of reception of the last Msg2. Msg2 can be of the common or separate type, and whether it is common or separate can be set by the reader. If the parameter indicating the monitoring interval for Msg2 is min or max, T offset1 The max point in time can be set as the reference point.

[0451] Fig. 59(b) shows that Msg2 is transmitted via the separate method. The monitoring start time for Msg2 is T D2R_nominal , T D2R_min , T D2R_max It can be any one of the following. The reference point for the aforementioned parameter is T offset1 Or it could be the time when the transmission of Msg1 is completed.

[0452] The monitoring start time is T D2R_min , or T D2R_max In the case of:

[0453] - T D2R_min , T D2R_maxWhen the first R2D transmission begins in between, Msg2 can be additionally monitored after the time interval (TR2D_R2D_min_for_differentDevice) for consecutive R2D transmissions for different devices. Msg0 may contain information indicating the number of R2D transmissions and the number of time resources for Msg2. Alternatively, individual Msg2 may contain an indicator indicating whether the corresponding message is the last or if additional Msg2s will be transmitted. The indicator may have a size of 1 bit. The device T, which indicates the transmission time of Msg3 after the last Msg2 has been received. offset1 Can instruct.

[0454] - T D2R_max The value can be set to a sufficiently long duration, and the terminal can monitor Msg2. The monitoring period of Msg2 may include up to the time of at least the second R2D Msg2 transmission transmitted by the reader, and T D2R_max It can also be configured accordingly. If the device fails to receive the first R2D, monitoring may be automatically terminated, and the delay time may be long. Therefore, T D2R_max If set to a large value, the device can receive the second message even if it fails to receive the first R2D message.

[0455] A 1-bit indicator that indicates whether the transmission method of Msg2 is common or separate can be included in the paging message.

[0456] FIG. 60 is a diagram showing the transmission relationship when there are two time resources for Msg1 according to one embodiment of the present specification.

[0457] FIG. 60 illustrates the case where the time resources for transmitting Msg1 in FIG. 59(a) are expanded to two. In the case where there are two time resources, T offset2 This needs to be defined. T offset2 Eun T offset1It can be set based on the point at which this ends. T offset2 It can be set by considering a fixed time interval so that the first D2R transmission and subsequent D2R transmissions do not overlap on the time axis, taking into account msg1_duration. offset2 can be set to a multiple of the R2D chip and / or bit length, or a multiple of the D2R chip and / or bit length. The monitoring time and interval of Msg2 can be set in the manner described above through FIG. 57(a). Alternatively, the monitoring time and interval of Msg2 are T nominal Value or T D2R_min , T D2R_maxThis can be applied and configured. Referring to FIG. 60, the transmission resources for Msg1 may be two in the time domain, and Msg1 may be transmitted in the FDM method in each time slot. When Msg3 is transmitted using one time resource and FDM, Common Msg2 and Msg3 may be repeated at least twice. All time and frequency resources may be used for Msg1, and Msg3 may be transmitted in only one time domain. In this case, the transmission of Msg3 corresponding to all Msg1s that have been successfully received cannot all be accommodated in a single time slot. Therefore, considering a structure such as FIG. 60, the device that transmitted Msg1 may wait for the next Msg2 for a certain time interval from the time Msg2 reception is completed if it receives the first Msg2 and there is no Msg2 response message for itself. The certain time interval may be described as TR2D_R2D_max_for_differentDevice. TR2D_R2D_max_for_differentDevice may represent the maximum time interval between consecutive R2D transmissions for different devices. TR2D_R2D_max_for_differentDevice may be time information that takes into account the time for the reader receiving Msg3 to prepare the next Msg2, and for the device receiving the first Msg2 to transmit Msg3 in response. The device receiving the first Msg2 is T offset1 Msg3 can be transmitted after a time. If the next Msg2 monitoring time is not specified using TR2D_R2D_max_for_differentDevice, T for Msg3 offset1 After T nominal Value or T D2R_min , T D2R_maxThe monitoring time can be determined by applying [this]. The first R2D message can indicate whether additional R2D messages are signaled after the first R2D message through a 1-bit indicator.

[0458] FIG. 61 is a diagram showing the relationship with Msg2 transmission when Msg1 according to one embodiment of the present specification can be transmitted using a plurality of time and frequency resources.

[0459] FIG. 61 illustrates a case where the Msg2 transmission described through FIG. 60 is a separate Msg2 transmission method, rather than a common Msg2 transmission. The device that transmitted Msg1 can determine the monitoring time and interval of Msg2 using the two methods described below.

[0460] - Method 1: The monitoring point for each Msg2 can be set / instructed by a nominal value. The monitoring start point for Msg2 is T offset2 It could be. offset2 Based on , the monitoring start time for each Msg2 is T offset_A1 , T offset_A2 It can be individually indicated as. The device is T offset_Ax You can monitor as many Msg2s as there are units. A device that receives Msg2 can transmit Msg3 based on the transmission resources allocated at the time of transmission. The time of transmission for Msg3 is T offset_Am3 It can be set based on the value. Alternatively, the transmission time of Msg3 is T after the completion of reception of the last Msg2. offset1 It could be a point in time that is a certain amount later. The point in time for monitoring the second separate Msg2s are T offset_Am3 Based on T offset_B1 , T offset_B2 , T offset_B3 It can be set by considering it.

[0461] - Method 2: The monitoring start time for Msg2 is Tnominal Value or T D2R_min , T D2R_max It can be set / instructed based on, and consecutive Msg2s can be transmitted after a certain interval. If there is a Msg3 transmission between consecutive Msg2 transmissions, the time interval between Msg2s may be longer. Accordingly, referring to FIG. 61, TR2D_R2D_max_for_differentDevice2 is defined, and the transmission time of Msg2 can be determined by applying TR2D_R2D_max_for_differentDevice2 based on the time when the last Msg2 is received before the transmission of Msg3. TR2D_R2D_max_for_differentDevice1 may be a value that considers the preparation time of consecutive R2D messages or the preparation time of the device receiving consecutive R2D messages. TR2D_R2D_max_for_differentDevice2 may be a value determined by considering the Msg3 transmitted between consecutive Msg2s. TR2D_R2D_max_for_differentDevice2 can be set / instructed as a multiple of the R2D or D2R chip and / or bit length. T D2R_max It can be configured to consider only the completion of reception of the first R2D message, or it can be configured to consider the time of completion of reception of the first message and the time of reception of the second Msg2. Since the device may terminate the process of receiving Msg2 if it fails to receive the first Msg2, the start time for monitoring Msg2 can be determined by considering the case where reception of the first Msg2 fails and reception of the second Msg2 succeeds. D2R_min , T D2R_max Instead of T nominal If the monitoring start time of Msg2 is set to a value, the monitoring start time of Msg2 is T offset2 It can be determined based on .

[0462] - Method 3: The monitoring start time for Msg2 is TD2R_min , T D2R_max It can be set / instructed as. In this case, the last R2D message is T D2R_max Transmission may need to be completed within. The device does not need to know the number of R2D messages, and T D2R_min , T D2R_max R2D messages can be monitored only within the interval. Msg3 is T D2R_max Timing parameters can be set / instructed starting from [date]. In this specification, the timing parameter is the maximum time value for which the R2D message is monitored, T D2R_max It may include. Alternatively, timing parameters may be set / instructed based on the time of completion of reception of the last R2D message. When the Msg2s for the first Msg3 transmission are referred to as the first Msg2 group and the subsequent Msg2s as the second Msg2 group, T for the second Msg2 group D2R_min , T D2R_max is the time when the reception of the last R2D message of the first Msg2 group is completed, T of the first group D2R_max The timing parameter for Msg3 can be set / instructed based on the time point based on the time of transmission of Msg3 indicated by the timing parameter for Msg3.

[0463] FIG. 62 is a diagram illustrating the transmission of a Nack message for Msg3 according to one embodiment of the present specification.

[0464] Referring to FIGS. 62(a) and (b), the reader can transmit / indicate a Nack indicator for Msg3 of CBRA (contention-based random access). Devices that transmitted Msg3 can perform monitoring for a Nack message indicating whether the transmission of Msg3 was successful or failed after a certain time interval. The timing parameters required to perform monitoring for the Nack message can be set in the same way as the timing parameters applied to the relationship between Msg1 and Msg2. The start time for monitoring for the Nack message can be determined based on a parameter indicating the time of completion of the last reception of the first Msg2 or the time of transmission of Msg3. The start time for monitoring for the Nack message is T nominal Value or T D2R_min , T D2R_max It can be determined based on. If there is an R2D transmission for sending Nack messages, the monitoring start time for Nack messages is T based on the time when the last R2D transmission was completed. nominal Value or T D2R_min , T D2R_max It can be determined using. T in the case where there is no R2D transmission for Nack transmission. nominal Value or T D2R_max The monitoring start time for Nack messages for the second Msg2 group can be determined based on the reference point.

[0465] FIG. 63 is a diagram showing the relationship between CBRA (contention-based random access) and CFRA (contention-free random access) according to one embodiment of the present invention.

[0466] Referring to FIG. 63, CBRA allows the reader and the terminal to complete the process of recognizing and registering each other through Msg1 and Msg2 following the paging message. However, since CFRA communicates when the reader has already recognized and registered the terminal's information, the exchange process of Msg1 and Msg2 is omitted, and the device can immediately transmit Msg3 after the paging message. In this case, an indicator indicating whether it is CBRA or CFRA exists in the paging message. If the paging message indicates CFRA, it may include an indicator indicating that it is CFRA with a value (e.g., 0) indicating that there are no time resources for Msg1, or an indicator indicating that Msg1 and Msg2 do not exist. Additionally, if it is CFRA, an indicator indicating any single or multiple devices may be included in the paging message. FDM resource allocation for the transmission of Msg3 may allocate as many resources as are available in Msg3 or allocate multiple devices simultaneously. Resource allocation can be directed by a combination of {Device ID, R value}. Alternatively, allocation can be made by mapping the ascending / descending order of the device ID to the ascending / descending order of the R value.

[0467] T described in this specification offset These may be applied commonly to devices or individually to each device. The service can operate as Inventory only or Inventory and command. If it is Inventory only, the process ends with the transmission of Msg0 and Msg1; if it is Inventory + command, Msg0, 1, 2, and 3 may be transmitted. Therefore, a 1-bit indicator may be included in the paging message to indicate whether it is operating as Inventory only. Alternatively, the value of the monitoring parameter in Msg2 is 0 or T nominal The value is 0 or T D2R_min , T D2R_max Both are 0 or TD2R_min , T D2R_max From T D2R_max If the value is 0, it may indicate Inventory only.

[0468] FIG. 64 illustrates a method for performing wireless communication according to one embodiment of the present specification.

[0469] Referring to FIG. 64, a method for performing wireless communication between a device and a reader as described in FIG. 1 to FIG. 63 will be explained.

[0470] The device can receive PRDCH (physical reader-to-device channel) (S6410). The device can transmit PDRCH (physical device-to-reader channel) in response to the PRDCH (S6420).

[0471] The above PDRCH can be transmitted at a point in time after the first interval from the time when the reception of the above PRDCH is completed.

[0472] The first interval above can be determined based on a first offset determined based on the chip length of the PDRCH.

[0473] The chip length of the above PDRCH can be determined based on the SFS (small frequency shift) factor.

[0474] The above SFS factor may be the smallest value among the available SFS factors for the device.

[0475] The first offset above is determined based on N times the chip length of the PDRCH, and N can be an integer.

[0476] In the case where there are multiple PDRCHs, the first interval is determined by additionally considering a second offset, the second offset is determined based on K times the chip length of the PRDCH, and N and K may be different from each other.

[0477] The above first interval can be determined by additionally considering the length of the above PDRCH.

[0478] The above wireless communication system may be an A-IoT (ambient-internet of things) system.

[0479] The above PRDCH may be a paging message for a random access procedure.

[0480] The device may be configured to include a communication module for transmitting and receiving wireless signals and a processor for controlling the communication module.

[0481] Although the method and system of the present invention have been described in relation to specific embodiments, some or all of their components or operations may be implemented using a computing system having a general-purpose hardware architecture.

[0482] The foregoing description of the present invention is for illustrative purposes only, and those skilled in the art will understand that other specific forms can be easily modified without altering the technical spirit or essential features of the present invention. Therefore, the embodiments described above should be understood as illustrative in all respects and not restrictive. For example, each component described as a single unit may be implemented in a distributed manner, and components described as distributed may likewise be implemented in a combined form.

[0483] The scope of the present invention is defined by the claims set forth below rather than by the detailed description above, and all modifications or variations derived from the meaning and scope of the claims and equivalent concepts thereof should be interpreted as being included within the scope of the present invention.

Claims

A device that performs wireless communication in a wireless communication system is, Communication module; and It includes a processor that controls the above communication module, and The above processor is, Receive PRDCH (physical reader-to-device channel), and Transmit PDRCH (physical device-to-reader channel) in response to the above PRDCH, and The above PDRCH is transmitted at a point in time after a first interval from the time when the reception of the above PRDCH is completed, and, The above first interval is a device determined based on a first offset determined based on the chip length of the above PDRCH. In Article 1, A device in which the chip length of the above PDRCH is determined based on the SFS (small frequency shift) factor. In Paragraph 2, The above SFS factor is the smallest value among the available SFS factors for the device. In Paragraph 3, The first offset above is determined based on N times the chip length of the PDRCH, and The above N is an integer, a device. In Paragraph 4, If the above PDRCH is multiple, The above first interval is determined by additionally considering the second offset, and The second offset is determined based on K times the chip length of the above PRDCH, and The above N and the above K are different devices. In Article 1, A device in which the first interval is determined by additionally considering the length of the PDRCH. In Article 1, The above wireless communication system is a device that is an A-IoT (ambient-internet of things) system. In Article 1, The above PRDCH is a device that is a paging message for a random access procedure. In a wireless communication system, the method performed by the device is, A step of receiving PRDCH (physical reader-to-device channel); and The method includes the step of transmitting a PDRCH (physical device-to-reader channel) in response to the above PRDCH, and The above PDRCH is transmitted at a point in time after a first interval from the time when the reception of the above PRDCH is completed, and, The above first interval is determined based on a first offset determined based on the chip length of the above PDRCH. In Article 9, A method in which the chip length of the above PDRCH is determined based on the SFS (small frequency shift) factor. In Article 10, The above SFS factor is the smallest value among the available SFS factors for the device, a method. In Paragraph 11, The first offset above is determined based on N times the chip length of the PDRCH, and The above N is an integer, method. In Paragraph 12, If the above PDRCH is multiple, The above first interval is determined by additionally considering the second offset, and The second offset is determined based on K times the chip length of the above PRDCH, and The above N and the above K are different methods. In Article 9, A method in which the above first interval is determined by additionally considering the length of the above PDRCH. In Article 9, The above wireless communication system is an A-IoT (ambient-internet of things) system, a method. In Article 9, The above PRDCH is a method that is a paging message for a random access procedure.

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