Method for transmitting signal in wireless communication system and apparatus therefor

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, wherein the processor receives information related to a physical device-to-reader channel (PDRCH), the information including an indicator indicating whether an additional midamble exists at the end of the PDRCH, and transmits the PDRCH configured on the basis of the information, wherein when the indicator indicates that the additional midamble exists at the end of the PDRCH, the additional midamble is located at the end 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 information related to a PDRCH (physical device-to-reader channel), the information includes an indicator that indicates whether an additional midamble exists at the very end of the PDRCH, transmits the PDRCH configured based on the information, and if the indicator indicates that an additional midamble exists at the very end of the PDRCH, the additional midamble may be located at the very end of the PDRCH.

[0012] Additionally, in the present specification, a method performed by a device performing wireless communication comprises the steps of: receiving information related to a PDRCH (physical device-to-reader channel); the information including an indicator indicating whether an additional midamble exists at the very end of the PDRCH; and transmitting the PDRCH configured based on the information, wherein if the indicator indicates that an additional midamble exists at the very end of the PDRCH, the additional midamble may be located at the very end of the PDRCH.

[0013] In addition, the above indicator may be 1 bit in size.

[0014] Additionally, the above PDRCH includes a preamble and a midamble, and the sequence of the preamble, the sequence of the midamble, and the sequence of the additional midamble may all be the same specific sequence.

[0015] In addition, the above specific sequence may be composed of 0 and 1, and may be configured such that there is one more 1 than 0.

[0016] In addition, the length of the specific sequence above may be 7 or 31.

[0017] In addition, if the length of the specific sequence is 7, the initial value of the specific sequence may be 1 0 0.

[0018] In addition, the above mid-amplifiers may be positioned at equal intervals.

[0019] In addition, the above information may include a small frequency shift (SFS) factor value (R).

[0020] In addition, if R is greater than 1, the transmission time of the PDRCH may be 1 / R of the transmission time when R is 1.

[0021] If R is greater than 1, the PDRCH can be repeated R times during the transmission time when R is 1.

[0022] In addition, the above PDRCH can be repeated in a form where the value mapped by the OOK (On-off keying) modulation method is repeated.

[0023] In addition, the above information may include information regarding the TBS (transport block size) of the PDRCH.

[0024] In addition, the above wireless communication system may be an A-IoT (ambient-internet of things) system.

[0025] The purpose of this specification is to provide a method for transmitting a signal in a wireless communication system.

[0026] Figure 1 shows an example of a wireless frame structure used in a wireless communication system.

[0027] Figure 2 shows an example of a downlink (DL) / uplink (UL) slot structure in a wireless communication system.

[0028] Figure 3 is a diagram illustrating a physical channel used in a 3GPP system and a general signal transmission method using said physical channel.

[0029] Figure 4 illustrates an SS / PBCH block for initial cell connection in a 3GPP NR system.

[0030] Figure 5 illustrates a procedure for transmitting control information and control channels in a 3GPP NR system.

[0031] 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.

[0032] Figure 7 is a diagram illustrating a method for setting up a PDCCH search space in a 3GPP NR system.

[0033] Figure 8 is a conceptual diagram explaining carrier aggregation.

[0034] Figure 9 is a diagram illustrating single-carrier communication and multi-carrier communication.

[0035] Figure 10 is a diagram illustrating an example where a cross-carrier scheduling technique is applied.

[0036] FIG. 11 is a diagram showing the configuration of a terminal and a base station according to one embodiment of the present specification.

[0037] FIG. 12 is a diagram showing the topology of an Ambient IoT (Internet of Everything) according to one embodiment of the present invention.

[0038] FIG. 13 is a diagram illustrating a random access operation in an A-IoT system according to one embodiment of the present specification.

[0039] FIG. 14 is a diagram illustrating the process of generating information of PRDCH according to one embodiment of the present specification.

[0040] FIG. 15 is a diagram illustrating the process of generating information of PDRCH according to one embodiment of the present specification.

[0041] FIG. 16 is a drawing showing line coding according to one embodiment of the present specification.

[0042] FIG. 17 is a diagram showing a Miller code among line coding methods according to one embodiment of the present specification.

[0043] FIG. 18 is a diagram illustrating the inventory process of an A-IoT system according to one embodiment of the present specification.

[0044] FIG. 19 is a diagram illustrating multiple access to Msg-1 in an inventory process according to one embodiment of the present specification.

[0045] 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.

[0046] 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.

[0047] 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.

[0048] 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.

[0049] 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.

[0050] 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.

[0051] 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.

[0052] 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.

[0053] 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.

[0054] FIG. 30 is a drawing showing the preamble, midamble, and postamble of a PDRCH according to one embodiment of the present specification.

[0055] FIG. 31 is a diagram illustrating a method for adding a mid-ampl of PDRCH according to one embodiment of the present specification.

[0056] FIG. 32 is a diagram showing the structure of a PDRCH considering an amble and CRC according to one embodiment of the present specification.

[0057] FIG. 33 is a diagram illustrating a method of dividing data when a device according to one embodiment of the present specification transmits data to a reader.

[0058] FIG. 34 is a diagram illustrating a method in which a CRC is added at regular intervals during data transmission according to one embodiment of the present specification.

[0059] FIGS. 35 and 36 are diagrams illustrating Frequency Division Multiple Access (FDMA) based on SFS in transmitting PDRCH according to one embodiment of the present specification.

[0060] FIG. 37 is a diagram illustrating a method for matching the same data rate in different frequency resources when PDRCH using FDMA is transmitted according to one embodiment of the present specification.

[0061] FIG. 38 is a diagram illustrating multiplexing and multiple access methods in the Msg1 transmission process according to one embodiment of the present specification.

[0062] FIGS. 39 to 41 are drawings illustrating a method of transmitting Msg2 and Msg3 according to one embodiment of the present specification.

[0063] FIG. 42 is a diagram showing the structure of Msg1 FDMed in CBRA (Contention-based Random access) according to one embodiment of the present specification.

[0064] FIG. 43 is a diagram showing Msg1 transmitted in a plurality of time and frequency domain resources in a CBRA according to one embodiment of the present specification.

[0065] FIG. 44 is a diagram showing a structure in which Msg1 and Msg3 are FDM-transmitted according to one embodiment of the present specification.

[0066] FIG. 45 is a diagram showing a frame structure that can be considered during R2D transmission according to one embodiment of the present specification.

[0067] FIG. 46 is a diagram illustrating a method of applying different M values ​​in an R2D frame structure according to one embodiment of the present specification.

[0068] FIGS. 47 to 50 are drawings illustrating a method of configuring CP.

[0069] FIGS. 51 and FIGS. 52 are drawings showing the channel structure of an R2D transmission according to one embodiment of the present specification.

[0070] FIG. 53 is a diagram showing a case where there are two time domain resources supporting TDMA according to one embodiment of the present specification.

[0071] FIG. 54 illustrates a method for performing wireless communication according to one embodiment of the present specification.

[0072] 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.

[0073] 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.

[0074] 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.

[0075] 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".

[0076] 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".

[0077] 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.

[0078] Figure 1 shows an example of a wireless frame structure used in a wireless communication system.

[0079] 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).

[0080] 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.

[0081] 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 specified, 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.

[0082] 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).

[0083] 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.

[0084] 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.

[0085] 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.

[0086] 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.

[0087] 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.

[0088] 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.

[0089] 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.

[0090] 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.

[0091]

[0092] 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.

[0093] 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.

[0094] 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.

[0095] 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.

[0096] 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.

[0097] 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.

[0098] 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.

[0099] 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.

[0100] After the procedure described above, the terminal may 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 may 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.

[0101] Figure 4 illustrates an SS / PBCH block for initial cell connection in a 3GPP NR system.

[0102] 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).

[0103] 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.

[0104]

[0105] The SS can be grouped into 336 physical layer cell identifier groups, each containing three unique identifiers, such that a total of 1008 unique physical layer cell IDs are generated through a combination of three PSSs and SSSs. Specifically, 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.

[0106]

[0107] Here, And,

[0108] It is given as.

[0109] Also, the sequence d of the SSS SSS (n) is as follows.

[0110]

[0111] Here, And,

[0112] It is given as.

[0113] 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.

[0114] 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.

[0115] 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.

[0116] 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.

[0117] Figure 7 is a diagram illustrating a method for setting up a PDCCH search space in a 3GPP NR system.

[0118] 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.

[0119] 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.

[0120] 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.

[0121] 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".

[0122] Table 3 shows an example of a PUCCH (physical uplink control channel) used in a wireless communication system.

[0123]

[0124] PUCCH can be used to transmit the following uplink control information (UCI).

[0125] - SR (Scheduling Request): Information used to request uplink UL-SCH resources.

[0126] - 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.

[0127] - 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.

[0128] In 3GPP NR systems, five PUCCH formats can be used to support various service scenarios, various channel environments, and frame structures.

[0129] 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.

[0130] 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.

[0131] 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.

[0132] 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.

[0133] 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.

[0134] 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.

[0135] 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.

[0136] 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.

[0137] 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.

[0138] Figure 8 is a conceptual diagram explaining carrier aggregation.

[0139] 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.

[0140] 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.

[0141] 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.

[0142] 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.

[0143] 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.

[0144] 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.

[0145] 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).

[0146] 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.

[0147] 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.

[0148] 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.

[0149] 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.

[0150] 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.

[0151] 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.

[0152] 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.

[0153] 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).

[0154] 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.

[0155] 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.

[0156] 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.

[0157] 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.

[0158] 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.

[0159] 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.

[0160] 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.

[0161] 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).

[0162] 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).

[0163] 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.

[0164] 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.

[0165] 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.

[0166] 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.

[0167] 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.

[0168] 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.

[0169] FIG. 12 is a diagram showing the topology of an Ambient IoT (Internet of Everything) according to one embodiment of the present invention.

[0170] 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.

[0171] 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.

[0172] 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.

[0173] There can be various topologies that constitute an A-IoT system. The following is an explanation of the basic terms used in topology.

[0174] 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.

[0175] 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).

[0176] 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.

[0177] - 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.

[0178] - 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.

[0179] - 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.

[0180] Device 2b has a relatively more complex configuration than devices 1 and 2a and may have superior performance.

[0181] Base Station (BS): The BS can be an NR BS / NR indoor BS / gNB (gNodeB), and the BS can communicate with a reader.

[0182] CW2D: CW2D can refer to the transmission of CW from a CW node to a device.

[0183] 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).

[0184] 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).

[0185] 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.

[0186] 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.

[0187] 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.

[0188] 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.

[0189] 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)).

[0190] 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.

[0191] - Inventory Mode: Inventory mode may be a mode performed by the network to search for A-IoT device identifiers and collect A-IoT devices.

[0192] - Command Mode: Command mode can be a mode (e.g., read, write) that the network performs to transmit work instructions to A-IoT devices.

[0193] FIG. 13 is a diagram illustrating a random access operation in an A-IoT system according to one embodiment of the present specification.

[0194] 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.

[0195] - 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)).

[0196] - 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.

[0197] 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).

[0198] FIG. 14 is a diagram illustrating the process of generating information of PRDCH according to one embodiment of the present specification.

[0199] PRDCH can be the channel used when a reader transmits data to a device.

[0200] 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.

[0201] 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.

[0202] - Time domain resource allocation

[0203] - Frequency domain resource allocation

[0204] - MCS (Modulation and coding scheme)

[0205] - TBS(Transport Block Size)

[0206] - Chip duration

[0207] - 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)

[0208] FIG. 15 is a diagram illustrating the process of generating information of PDRCH according to one embodiment of the present specification.

[0209] PDRCH may be a channel used when a device transmits data to a reader.

[0210] 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.

[0211] - MCS (Modulation and Coding Techniques, e.g., Data Modulation, Line / Channel Coding)

[0212] - Receiving methods (receiving techniques, e.g., coherent or non-coherent)

[0213] - D2R transmission length / packet size

[0214] - Midamble overhead

[0215] - Timing / frequency accuracy

[0216] - Phase accuracy

[0217] FIG. 16 is a drawing showing line coding according to one embodiment of the present specification.

[0218] Specifically, Fig. 16 is a diagram showing FM0, which is one of the line coding methods.

[0219] 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.

[0220] FIG. 17 is a diagram showing a Miller code among line coding methods according to one embodiment of the present specification.

[0221] 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.

[0222] Square-wave coding can also be used in line coding methods, unlike those shown in FIGS. 16 and 17.

[0223] FIG. 18 is a diagram illustrating the inventory process of an A-IoT system according to one embodiment of the present specification.

[0224] 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.

[0225] - T R2D_min : Minimum time between R2D transmission and the D2R transmission corresponding to the R2D transmission

[0226] - T D2R_min : Minimum time between D2R transmission and the R2D transmission corresponding to the D2R transmission

[0227] - T R2D_R2D_min : Minimum time between consecutive R2D transmissions sent to the same device

[0228] - T D2R_D2R_min : Minimum time between consecutive D2R transmissions from the same device

[0229] FIG. 19 is a diagram illustrating multiple access to Msg-1 in an inventory process according to one embodiment of the present specification.

[0230] 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.

[0231] 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.

[0232] 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.

[0233] 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.

[0234] 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.

[0235] 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.

[0236] 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.

[0237] The leader can instruct the resource allocation method through paging (PRDCH) messages. The resource allocation method using paging messages is described below.

[0238] 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.

[0239] 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.

[0240] 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.

[0241] 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.

[0242] 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.

[0243] Referring to Fig. 21, resource allocation in PDRCH can be distinguished based on time gaps.

[0244] 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.

[0245] 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.

[0246] 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.

[0247] 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.

[0248] 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.

[0249] 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.

[0250] 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.

[0251] 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.

[0252] 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.

[0253] 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.

[0254] 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.

[0255] 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.

[0256] 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 a regular time interval 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.

[0257] 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.

[0258] 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.

[0259] 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.

[0260] 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.

[0261] 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.

[0262] FIG. 30 is a drawing showing the preamble, midamble, and postamble of a PDRCH according to one embodiment of the present specification.

[0263] Data transmitted by the device to the reader may be transmitted via PDRCH. PDRCH may be configured to include some or all of a preamble, a midamble, and a postamble. The preamble may be located at the very beginning of the PDRCH, and the postamble may be located at the very end of the PDRCH. Data transmitted by the device to the reader may be divided into multiple data and transmitted via PDRCH, and a midamble may be located between each of the multiple data. In the present specification, if there are multiple midambles, the midambles may be located at equal intervals.

[0264] A preamble may be required to correct the Sampling Frequency Offset (SFO) for acquiring time information. The preamble may be configured in the form of a sequence (e.g., a binary sequence). The sequence may have good autocorrelation and cross-correlation characteristics, and line coding may be applied. In this case, the sequence may be an M-sequence, a Golay sequence, or a Walsh sequence. The sequence length may be a pre-set length. Additionally, multiple different sequences of the same length may be used to constitute the preamble. The type of sequence (i.e., which sequence to use in PDRCH) can be set through R2D control information. R2D control information may be information transmitted or set by the device to the reader. Sequences may be used selectively based on the type of amble, message type, command type, traffic type, device group / signal type, etc.

[0265] The postamble can be located at the very end of the PDRCH and can be used by the reader to obtain the final location information where the PDRCH ends. Alternatively, the reader may use control information to obtain the final location information of the PDRCH. The reader may obtain the length information of the PDRCH based on specific information included in the control information and use the length information to obtain the final location information of the PDRCH. Additionally, the postamble can be used to obtain time synchronization information (i.e., SFO) for receiving previously transmitted data. The control information may be D2R control information or R2D control information.

[0266] Midambles can be placed between data for PDRCH data. Additionally, midambles can be used to obtain time information (i.e., SFO), channel estimation, interference estimation, and carrier frequency offset (CFO).

[0267] When the device transmits PDRCH to the reader, the configuration options for the D2R amble that can be considered may be as follows.

[0268] - Preamble only (D2R Preamble only)

[0269] - Preamble and X Midambles (D2R Preamble + X Midamble(s)) X can be greater than or equal to 1

[0270] - Preamble and Postamble (D2R Preamble + Postamble)

[0271] Preamble, Y Midambles, and Postamble (D2R Preamble + Y Midamble(s) + Postamble) Y may be greater than or equal to 1

[0272] Referring to Fig. 30(a), a preamble may be located at the very beginning of the PDRCH, a midamble may be located between each data, and a postamble may be located at the very end of the PDRCH. In this case, the number of midambles may be 1 or more.

[0273] Referring to FIG. 30(b), a preamble may be located at the very beginning of the PDRCH, midambles may be located between each data, and a postamble may not exist. The number of midambles may be one or more. Although only one midamble is shown in the figure, if the length of the data is long, the data may be divided into multiple parts of a reference size, and a midamble may be located between each of the divided multiple data parts. If the last midamble is located and the remaining data area is less than or equal to the reference size, the postamble may not be included in the PDRCH. This may be because the time synchronization effect through the postamble is minimal when the amount of remaining data is small. Information regarding the length of the PDRCH may be indicated through R2D control information or D2R control information. Additionally, whether a postamble exists may be indicated through R2D control information or D2R control information. Whether a postamble exists may be indicated by a 1-bit indicator.

[0274] Referring to Fig. 30(c), a preamble may be located at the very beginning of the PDRCH, a midamble may be located between each data, and a postamble may be located at the very end of the PDRCH. Unlike Fig. 30(b), a postamble may be located at the very end of the PDRCH even when the amount of remaining data after the last midamble is small (less than the amount of other partitioned data).

[0275] Referring to FIG. 30(d), the PDRCH can be composed of a preamble and data. When the amount of data transmitted by the device is relatively small and the reader can obtain the length information of the data in advance or derive it by other means, a PDRCH structure such as FIG. 30(d) may be used. Alternatively, a PDRCH structure such as FIG. 30(d) may be used to simplify the transmission structure.

[0276] Referring to FIG. 30(e), PDRCH can be composed of a preamble, data, and a postamble. The reader can use the postamble to derive the last information of the data without separate signaling, and can improve reception performance by performing SFO estimation and channel measurement.

[0277] The chip length for a preamble sequence may be a pre-set fixed length. If a midamble is present in the PDRCH, the chip length for the midamble sequence may be determined based on the value M. The value M is related to OOK modulation and may be a parameter that determines the number of possible OOK chips in an OFDM symbol. If a postamble is present in the PDRCH, the chip length for the postamble sequence may be determined based on the value M. Since the chip length of the preamble is fixed, a relatively long chip length can be configured, allowing the reader to secure sufficient reception time for the first signal received from the device, which can be efficient for SFO estimation. The midamble and postamble may have different chip lengths from the preamble. The base station can perform SFO estimation using the midamble and postamble. The number and length of chips in the preamble sequence can be measured accurately, while the midamble and postamble, which are relatively short in length, may be measured inaccurately. However, the reader can correct the sequence lengths and chip lengths of the midamble and postamble obtained through control information (R2D control information or D2R control information) and the actual estimated sequence and chip lengths based on SFO information obtained using the preamble. The midamble sequence and / or postamble may be identical to the preamble sequence. That is, the midamble sequence and / or postamble may have the same size and pattern as the preamble sequence. Alternatively, the midamble sequence and / or postamble may be part of the preamble sequence. This may have the effect of reducing the implementation complexity of the estimation logic when the reader decodes the midamble sequence and / or postamble. Alternatively, if a postamble is present, the chip length of the postamble sequence may be a fixed length. If the chip length of the preamble and the chip length of the postamble are the same, the reader can more easily estimate the device's SFO.If data transmission times are long, the estimation of chips located in the latter part of the data transmission may be inaccurate due to time drift in the device clock, and correction may be required. When the preamble and postamble have relatively long chip lengths, the reader can easily estimate the SFO. Furthermore, when the preamble and postamble have relatively long chip lengths, SFO estimation through edge detection or SFO hypotheses may become more accurate or less complex. SFO hypotheses may be a method that utilizes the correlation characteristics of sequences to calculate correlations between multiple candidate sequences and identify sequences with high correlation characteristics.

[0278] FIG. 31 is a diagram illustrating a method for adding a mid-ampl of PDRCH according to one embodiment of the present specification.

[0279] If the amount of data to be transmitted by the device is large, the transmission time of the data may increase relatively. Consequently, the time drift phenomenon becomes larger, and the SFO may accumulate more and more. This may lead to a decrease in decoding performance when the reader receives the data. To address the problem of decoding performance degradation, when the device transmits data exceeding a certain size, one or more midambles may be included in the PDRCH.

[0280] A method for adding a mid-amplifier will be explained below with reference to FIG. 31.

[0281] Referring to FIG. 31(a), the device can divide the data length into a preset size value (X) and add a midamble for every X data transmission. If the X value is fixed, there may be no additional signaling indicating the X value. In this case, the size of the last data region (remaining bits) may be equal to or smaller than the preset size value (X).

[0282] Referring to FIG. 31(b), the reader can be configured to divide the data evenly and add Y midambles through R2D control information. The data can be divided into Y+1 parts and Y midambles can be added. In this case, the bit size of the divided data can all be the same (A bits in FIG. 31(b)). However, depending on the size of the data, it may not be divided evenly. In this case, the data can be divided such that the size of the divided data differs by N. N is a natural number and can be 1. For example, if the size of the data is 29 bits and it is divided into 4 data, the size of each data can be 8, 7, 7, 7 (or 7, 7, 7, 8). If the size of the data is 30 bits and it is divided into 4 data, the size of each data can be 8, 8, 7, 7 (or 7, 7, 8, 8). If the size of the data is 31 bits and it is divided into 4 data, the size of each data may be 8, 8, 8, 7 (or 7, 8, 8, 8). Each data may be divided based on a reference size, and as described above, if the sizes of each data are not all the same, data that differs from the reference size may be set to be N larger (+N) than the reference size or N smaller (-N).

[0283] Referring to FIG. 31(c), the data size (interval) value (Z) can be indicated through R2D control information. In this case, the size of the last data area (remaining bits) may be equal to or smaller than the Z value. FIG. 31(c) can receive a data size value from the reader, rather than a fixed size X compared to FIG. 31(a).

[0284] FIG. 32 is a diagram showing the structure of a PDRCH considering an amble and CRC according to one embodiment of the present specification.

[0285] Cyclic Redundancy Check (CRC) can be used to detect errors in data. CRC can be added to information bits, and Forward Error Correction (FEC), line coding, small frequency shift (SFS), modulation, etc., can be applied to the PDRCH containing CRC. Repetition to increase the transmission success rate can be added before or after applying FEC. The CRC length can be a 6-bit CRC (gCRC6(D)=[D6+D5+1]) and a 16-bit CRC (gCRC16(D)=[D16+D11+D6+D5+1]).

[0286] Figures 32(a), (b), (c), and (d) show the locations of CRCs included in PDRCH.

[0287] FIG. 32(a) has the same Amble structure as FIG. 30(a) but with a CRC added. FIG. 32(b) has the same Amble structure as FIG. 30(b) but with a CRC added. FIG. 32(d) has the same Amble structure as FIG. 30(c) but with a CRC added. FIG. 32(c) shows the structure of FIG. 32(b) with a post-Amble added.

[0288] Data#N transmitted after the last midamble may have a relatively small data size (smaller than other data), but if the message type / command type is random access or a control message, a postamble may be added to improve reception performance.

[0289] FIG. 33 is a diagram illustrating a method of dividing data when a device according to one embodiment of the present specification transmits data to a reader.

[0290] Depending on the large data size, communication conditions, or resource conditions, the device may divide and transmit long data. For example, when transmitting data with the configuration shown in FIG. 33(a), the device may divide the PDRCH into two parts as shown in FIG. 33(b) and transmit it over two transmission opportunities. In this case, a CRC may be added to the last data of each transmission. Referring to FIG. 33(b), the device may divide the PDRCH into two parts and perform two transmissions, and a CRC may be added to the end of each divided transmission data. The length of the CRC may be determined based on the size of the data. For example, when a 6-bit CRC and a 16-bit CRC are used, if the current data transmission size is smaller than the data size at which the 6-bit CRC can detect errors, the 6-bit CRC may be used, and if the current data transmission size is larger, the 16-bit CRC may be used. Alternatively, a 16-bit CRC may be used regardless of the size of the transmitted data for the convenience of the receiving device. Referring to FIG. 33(c), a postamble may be placed at the end of all divided transmissions. As a result, the receiving device (e.g., reader) can know the end of the data and can also perform CFO, SFO, and interference estimation.

[0291] FIG. 34 is a diagram illustrating a method in which a CRC is added at regular intervals during data transmission according to one embodiment of the present specification.

[0292] If the size of the data to be transmitted is large, the transmission time / reception time increases relatively, reception performance may be degraded by the SFO, and problems such as buffer size and decoding time delays may occur. To solve these problems, the present specification proposes a structure of PDRCH as shown in FIG. 34. Referring to FIG. 34, a plurality of midambles and postambles may be added to the PDRCH. Specifically, a CRC may be added after a certain amount of data has been transmitted. Alternatively, a CRC may be added after a certain number of midambles have been transmitted. Compared to a receiving device that checks the CRC and decodes the data after receiving all data, the device checks the CRC and decodes the data on a CRC-by-CRC basis, thereby enabling it to quickly determine whether individual transmitted data has been successfully received.

[0293] PDRCH in FIGS. 35 to 37 may refer to an area where only data exists without ambles (data area in FIGS. 30 to 34, etc.).

[0294] FIGS. 35 and 36 are diagrams illustrating Frequency Division Multiple Access (FDMA) based on SFS in transmitting PDRCH according to one embodiment of the present specification.

[0295] Based on SFS, the number of FDM possible during PDRCH transmission can be determined. When SFS is applied, the chip length can be reduced by 1 / M or 1 / R depending on the SFS factor M (or R) value. Referring to Fig. 35, as the value of R increases, the chip length can be reduced proportionally to the value of R. That is, based on the case where R is 1, the transmission time for transmitting the same data can be reduced proportionally to the value of R. For example, if R is K, the transmission time can be 1 / K compared to the case where R is 1. That is, if R is 2, the transmission time is 1 / 2 compared to the case where R is 1, and if R is 4, the transmission time can be 1 / 4 compared to the case where R is 1. If R is 6, the transmission time can be 1 / 6 compared to the case where R is 1.

[0296] FIG. 35 illustrates only the preamble and PDRCH structure, and FIG. 36 illustrates a structure with a midamble added. Additionally, as disclosed in the present specification, a postamble and / or CRC may also be added to the structures of FIG. 35 and FIG. 36.

[0297] The preamble structure can be of various forms and lengths. For example, the preamble structure can be in the form of a binary sequence and can be 32 bits long. Various forms of sequence length can be used. The binary sequence can be an M-sequence or a Golay sequence. Alternatively, the preamble structure can be a pattern consisting of on / off that is not a binary sequence.

[0298] The midambler can have the same structure as the preambler. That is, the midambler can have the same shape and length as the preambler. The postambler can also have the same structure as the preambler.

[0299] FIG. 37 is a diagram illustrating a method for matching the same data rate in different frequency resources when PDRCH using FDMA is transmitted according to one embodiment of the present specification.

[0300] FIG. 37(a) illustrates a D2R transmission structure consisting of a preamble and a PDRCH. Referring to FIG. 37(a), when R is 2, the chip length is reduced by half compared to when R is 1, and the transmission time of the entire preamble and PDRCH can also be reduced by half. When D2R is transmitted via FDMA, different R values ​​can be used for each device. That is, each device can perform D2R transmission using frequency domain resources corresponding to different R values. In this case, to maintain the same data rate for each device, the mapping value of OOK (On-Off Keying) / BPSK modulation can be repeated as many times as the R value. For example, when OOK modulation is used, 1 can be chip-mapped as 01 and 0 as 10. In this case, if R is 2, it can be represented as 2R, and 1 can be 0101 (01 repeated twice) and 0 can be 1010 (10 repeated twice). For example, when BPSK modulation is used, 1 can be mapped to -1 +1 and 0 to +1 -1. In this case, if R is 2, it can be represented as 2R, where 1 is -1 +1 -1 +1, with -1 +1 repeated twice, and 0 is +1 -1 +1 -1, with +1 -1 repeated twice. By repeating the mapping values, the chip length is reduced by half, but the number of repetitions increases, so the same transmission rate can be maintained per frequency resource.

[0301] The preamble for D2R transmission may use a binary sequence, and line or non-line codes may be applied. If the Manchester code is applied among line codes, the length of the preamble (32 bits) may be 64 chips. For convenience of explanation in this specification, the length of the preamble may be expressed as the length of the sequence. If expressed as the length with line codes applied to the preamble, it may be twice the length of the sequence. PDRCH_1R in FIG. 37(a) represents the case where the value of R is 1, and PDRCH_2R represents the case where OOK / BPSK is repeated twice. 3701 in FIG. 37 represents a D2R transmission structure consisting of the preamble and PDRCH when R is 1. It may be advantageous to maintain the preamble in the form of a sequence to preserve correlation characteristics. When the value of R is greater than 1, the following method may be applied to the preamble instead of the method of repeating the OOK / BPSK mapping value.

[0302] - The preamble can be repeated. That is, it can be repeated in units of sequence length (3702 in Fig. 37).

[0303] - The preamble is not repeated, and PDRCH can be transmitted repeatedly (3703 in Fig. 37).

[0304] - The preamble can be increased by a factor of R. That is, a sequence extended by a factor of R can be applied (3704 in Fig. 37).

[0305] Alternatively, the repetition of the preamble may not be arranged continuously, and the preamble may be repeated R-1 times after PDRCH. Or, R / 2 times the preamble may be placed before PDRCH, and the remaining R / 2 times the preamble may be placed after PDRCH.

[0306] FIG. 37(b) illustrates a D2R transmission structure consisting of a preamble, PDRCH, and a midamble. The midamble may be positioned after the PDRCH. For ambles that use binary sequences or maintain correlation characteristics, excluding the PDRCH, the method of repeating the preamble described in FIG. 37(a) may be applied. FIG. 37(b) also illustrates a preamble and a midamble with line codes applied, but for convenience of explanation, they are expressed in terms of sequence length. 3711 in FIG. 37 illustrates a D2R transmission structure consisting of a preamble, PDRCH, a midamble, and PDRCH when the R value is 1. When FDMA is used, the PDRCH may be repeated as many times as the R value to maintain the same data rate between devices using different R values.

[0307] Referring to 3712 in Fig. 37, the amble of the D2R transmission can be repeated as many times as R. That is, if the value of R is 2, the preamble and midamble can each be repeated 2 times in units of sequence length.

[0308] Referring to 3713 in FIG. 37, the preamble and midamble may not be repeated, and only PDRCH may be repeated. Alternatively, the preamble and midamble may not be repeated consecutively, and the preamble and midamble may be positioned after PDRCH. Alternatively, if the sequences of the preamble and midamble are different, the preamble and midamble may not be repeated consecutively, and the preamble may be repeated R times after PDRCH, or the midamble may be repeated R times after PDRCH. Alternatively, the preamble and midamble may not be repeated consecutively, and may be repeated R-1 times after PDRCH. Alternatively, the preamble and midamble may each be repeated R / 2 times, and the remaining R / 2 times may be positioned after PDRCH and repeated.

[0309] Referring to 3174 in Fig. 37, when the R value is 2, the length of the sequence can be doubled from 32 to 64.

[0310] The sequence M described in this specification may be a binary sequence having the longest period that can be generated by a Linear Feedback Shift Register (LFSR). The period of the sequence M may be 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 may be one more 1. For example, if n=3, a feedback polynomial of x^3 + x + 1 may be constructed, and the initial value may be 1 0 0. A sequence with an initial value of 1 0 0 may be effective in terms of maximum period, good autocorrelation, low cross-correlation, and randomness.

[0311] The Golay sequence described in this specification may consist of two binary sequences A and B, and the lengths of A and B may be equal. In addition, the two sequences A and B must satisfy the orthogonality condition. That is, the inner product of the two sequences must be zero (A●B=0). Such a Golay sequence can provide a high signal-to-noise ratio because the sum of the autocorrelation functions is equal to the delta function.

[0312] FIG. 38 is a diagram illustrating multiplexing and multiple access methods in the Msg1 transmission process according to one embodiment of the present specification.

[0313] Msg1 can be transmitted in various forms. Referring to 3801 in FIG. 38, Msg1 can be transmitted via TDMA. Referring to 3802 in FIG. 38, Msg1 can be transmitted via FDMA. Referring to 3803 in FIG. 38, Msg1 can be transmitted via a combination of TDMA and FDMA. In FIG. 38, the number of resources in the time domain is depicted as 2 and the number of resources in the frequency domain is depicted as 5; however, this is done for convenience of explanation only and is not limited thereto. 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 Common-Msg2. An individual Msg2 corresponding to each of multiple Msg1s in a single PRDCH may be a Separate-Msg2 (individual Msg2). Like Msg1, Msg3 can be configured and transmitted in various ways, such as TDMA, FDMA, or a combination thereof. Additionally, the transmission methods of Msg2 and Msg3 can also be configured in various forms depending on system requirements.

[0314] FIGS. 39 to 41 are drawings illustrating a method of transmitting Msg2 and Msg3 according to one embodiment of the present specification.

[0315] FIG. 39(a) illustrates an example of a Common-Msg2 structure, wherein Msg2 may contain response information for multiple Msg1s within a single message. 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 be an AS ID (Autonomous System Identifier), a random number of X bits, etc. X may be a positive integer. By transmitting Msg2 containing information about the terminal that transmitted Msg1, the terminal can know that communication with the reader has been successful. Additionally, Msg2 may explicitly or implicitly indicate resource allocation information for Msg3. Msg3 may be transmitted via FDMA. In this case, Msg2 may include information of a specific bit length and other details according to a defined format, in addition to device identifier information; the device can interpret the information based on the defined format and obtain resource allocation information for the FDMA method. Furthermore, the order of the device-specific information fields can be used as a standard for mapping resource locations in Msg3, and the order can be distinguished by device. Resource locations in Msg3 can also be mapped based on the order of the device-specific information fields. Msg3 can be transmitted via FDMA, enabling mapping of resources in the frequency domain, and each frequency domain resource can be determined based on the SFS value (R). Information related to time resources may also utilize pre-configured information. 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 allocated in the following manner.

[0316] i) Sequential Mapping Method: Based on the order of the device-specific information fields included in Common-Msg2, frequency domain resources can be mapped / assigned in order from the smallest R value to the largest R value. For example, frequency domain resources can be mapped / assigned in the form of f0 (R=2), f1 (R=4), f2 (R=8), f3 (R=16), and f4 (R=32). Alternatively, frequency domain resources can be mapped / assigned sequentially from the largest R value to the smallest R value.

[0317] ii) Maximum Spacing Mapping Method: Frequency domain resources can be filled starting from the furthest resource based on the order of the device-specific information fields included in Common-Msg2. That is, they can be allocated in a form where the R values ​​are spaced as far apart as possible. For example, when there are 5 frequency domain resources and 2 device information fields included in Msg2, the R values ​​can be mapped to the lowest and highest values ​​in the form of f0 and f4. As another example, if there are 5 frequency domain resources and 3 device information fields, they can be allocated / mapped in the order f0, f4, f2. As another example, if there are 5 frequency domain resources and 4 device information fields, they can be allocated / mapped in the order f0, f4, f2, f1 (or f3). As another example, if there are 5 frequency domain resources and 5 device information fields, they can be allocated / mapped in the order f0, f4, f2, f1, f3 (or f3, f1).

[0318] Referring to FIG. 39(b), Msg3 can support a combination of TDMA and FDMA methods. FIG. 39(b) illustrates an example of resource allocation when a combination of TDMA and FDMA methods is supported. Resources can be mapped / allocated in the following manner according to the order of device-specific information fields.

[0319] i) Sequential mapping method: Based on the order of the device information fields in Msg2, resources can be sequentially mapped / allocated in the form of f(0,0)~f(0,4) and f(1,0)~f(1,4).

[0320] ii) Maximum spacing mapping method within the same time resource: Based on the order of the device information fields of Msg2, resources can be mapped / assigned in a manner similar to Fig. 39(a) with the R values ​​spaced as far apart as possible. At this time, the first time domain resource can be mapped / assigned first, and the second time domain resource can be mapped / assigned.

[0321] iii) Resource cross-maximum interval mapping method 1: Based on the method ii) described above (maximum interval mapping method within resources at the same time), resources can be mapped / assigned in order with the R value and in a form that is as far apart as possible in the time domain. For example, resources can be mapped / assigned in the order of f(0,0), f(0,4), f(1,0), f(1,4), f(0,2), f(1,2) ....

[0322] iv) Resource Cross-Maximum Spacing Mapping Method 2: Similar to the method described in ii) above, resources can be mapped / assigned in a form that is as far apart as possible from the R value and the time domain. In this case, for the first time domain resource, the mapping / assignment of non-adjacent frequency domain resources can be performed first, and for the second time domain resource, the mapping / assignment of non-adjacent frequency domain resources can be performed. For example, resources can be mapped / assigned 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), and f(1,3). The order in which f(0,1) and f(0,3) are mapped / assigned to each other can be reversed. The same applies to f(1,1) and f(1,3).

[0323] v) Resources may be mapped / assigned in order of the most separated frequency domain resources among the frequency domain resources that are not used in the previous time resource domain, based on the method iii) described above (resource cross-maximum interval mapping method 1). v) may be a mapping / assignment method that considers SFO. For example, in the first slot, resources may be mapped / assigned in the order of f(0,0) and f(0,4), and in the second slot, resources may be mapped / assigned in the order of f(1,1) and f(1,3) that are most separated without overlapping with the frequency domain resources used in the first slot, and then the resource of f(0,2) may be mapped / assigned again in the first slot.

[0324] vi) Resources may be mapped / assigned in the order of maximum separation among frequency domain resources that are not used in the previous time resource domain, as in the method iv) described above (resource cross-maximum interval mapping method 2). vi) may be a mapping / assignment method that considers SFO. For example, resources may be mapped / assigned in the order of f(0,0), f(0,4), and f(0,2) in the first slot first, and then in the second slot, resources may be mapped / assigned in the order of f(1,1) and f(1,3) that are maximum separation without overlapping with the frequency domain resources used in the first slot.

[0325] The above-described methods v) and vi) are techniques configured to minimize collisions even when identical frequency domain resources in different time slots overlap due to SFO performance degradation of terminals, by preferentially mapping / allocating non-identical frequency domain resources in different time slots.

[0326] Referring to FIG. 39(c), multiple Separate-Msg2s may be transmitted from a reader, and Msg3 may be transmitted from multiple frequency domain resources. The methods described in FIG. 39(a) may be applied based on identifiers such as resource allocation indicators, message indexes, and message sequence indexes for the transmission of each Msg3 included in each Msg2. For example, resource allocation information included in Msg2 may indicate the frequency domain resource allocation method for Msg3. If the resource allocation information included in Msg2 includes index information, frequency domain resources for Msg3 transmission may be allocated / mapped in low order / high order based on the index information. Resources may be mapped in order from f0 to f4. Alternatively, the method of FIG. 39(a) or (b) may be applied to resources considering the R value.

[0327] FIG. 39(d) is a repeating form of FIG. 39(a), illustrating a method for transmitting Msg2 and Msg3 when resource mapping / allocation exceeds the structure of FIG. 39(a) based on conditions of information fields that may be included in Common-Msg2 or the configuration form of resources of Msg1. FIG. 39(d) may be a structure in which resource allocation for Msg1 simultaneously supports TDMA and FDMA. For example, if the number of time domain resources and the number of frequency domain resources are 2 and 5, respectively, Msg3 cannot be transmitted at once with the structure of FIG. 39(a), so Msg3 can be transmitted using a structure such as FIG. 39(b) or FIG. 39(d). FIG. 39(d) may be configured such that frequency domain resources corresponding to Common-Msg2 are repeated for each time domain resource of Msg1, and the method described through FIG. 39(a) may be applied to each time domain resource.

[0328] Referring to FIG. 40, the frequency domain resources may be an even number (e.g., 4). Based on the order of the device-specific information fields included in Common-Msg2, the frequency domain resources allocated to the device transmitting Msg3 may be configured as follows.

[0329] i) Sequential Mapping Method: Based on the order of device-specific information fields included in Common-Msg2, resources can be mapped / assigned in order from the smallest R value to the largest R value. For example, resources can be mapped / assigned in the order f0 (R=2), f1 (R=4), f2 (R=8), and f3 (R=16). Alternatively, resources can be mapped / assigned sequentially from the largest R value to the smallest R value.

[0330] ii) Maximum Spacing Mapping Method: Resources can be mapped / assigned starting from the furthest frequency domain resources based on the order of the device-specific information fields included in Common-Msg2. That is, resources can be mapped / assigned in a form where the R values ​​are spaced as far apart as possible. For example, when there are 4 frequency domain resources and 2 device information fields included in Msg2, the frequency domain resources can be mapped / assigned to f0, which has the lowest R value, and f3, which has the highest R value. Or, when there are 4 frequency domain resources and 3 device information fields, the frequency domain resources can be assigned / mapped in the order of f0, f4, f1 (or f2). Or, when there are 4 frequency domain resources and 4 device information fields, the frequency domain resources can be assigned / mapped in the order of f0, f3, f2, f1 (or f1, f2).

[0331] Referring to FIG. 40(b), Msg3 can be transmitted using a mixed TDMA and FDMA method. Resources for the transmission of Msg3 can be mapped / allocated in the following way according to the order of device-specific information fields.

[0332] i) Sequential mapping method: Based on the order of the device information fields in Msg2, resources can be mapped / allocated sequentially in the form of f(0,0)~f(0,3) and f(1,0)~f(1,3).

[0333] ii) Maximum spacing mapping method within the same time resource: Based on the order of the device information fields of Msg2, resources can be mapped / assigned in a manner similar to Fig. 40(a) with the R value spaced as far apart as possible. At this time, the first time domain resource can be mapped / assigned first, and the second time domain resource can be mapped / assigned.

[0334] iii) Resource Cross-Maximum Interval Mapping Method 1: Based on the method ii) described above (maximum interval mapping method within resources at the same time), resources can be mapped / assigned in order, separated as much as possible from the R value and the time domain. For example, resources can be mapped / assigned first in the order of f(0,0), f(0,3), f(1,0), and f(1,3). The remaining resources, f(0,2), f(1,2), f(0,1), and f(1,1), can be mapped / assigned in various combinations.

[0335] iv) Resource Cross-Maximum Spacing Mapping Method 2: As with the method described in ii) above, resources can be mapped / assigned in a form that is as far apart as possible from the R value and the time domain. At this time, for the first time domain resource, mapping / assignment of non-adjacent frequency domain resources can be performed first, and for the second time domain resource, mapping / assignment of non-adjacent frequency domain resources can be performed. For example, resources can be mapped / assigned first in the order of f(0,0), f(0,3), f(0,2), f(0,1) (or f(0,1), f(0,2)), and then mapped / assigned to f(1,0), f(1,3), f(1,2), f(1,1) (or f(1,1), f(1,2)).

[0336] v) Resources may be mapped / allocated in order of the most separated frequency domain resources among the frequency domain resources that are not used in the previous time resource domain, based on the method iii) described above (resource cross-maximum interval mapping method 1). v) may be a mapping / allocation method that considers SFO. For example, in the first slot, resources may be mapped / allocated in the order of f(0,0) and f(0,3), and in the second slot, resources may be mapped / allocated in the order of f(1,1) and f(1,2) that are most separated without overlapping with the frequency domain resources used in the first slot.

[0337] Resources may be mapped / assigned in order of maximum separation among frequency domain resources that are not used in the previous time resource domain, as described in method iv) above (resource cross-maximum interval mapping method 2). Method vi) may be a mapping / assignment method that considers SFO. For example, resources may be mapped / assigned in the order of f(0,0), f(0,3), f(0,1) (or f(0,2)) in the first slot first, and then in the second slot, resources of f(1,2) (or f(1,1)) that are maximum separation without overlapping with the frequency domain resources used in the first slot may be mapped / assigned.

[0338] The above-described methods v) and vi) are techniques configured to minimize collisions even when identical frequency resources in different time slots overlap due to SFO performance degradation of terminals, by preferentially mapping / allocating non-identical frequency domain resources in different time slots.

[0339] Referring to FIG. 40(c), multiple Separate-Msg2s may be transmitted from a reader, and Msg3 may be transmitted from multiple frequency domain resources. The methods described in FIG. 40(a) may be applied based on identifiers such as resource allocation indicators, message indexes, and message sequence indexes for the transmission of each Msg3 included in each Msg2. For example, resource allocation information included in Msg2 may indicate the frequency domain resource allocation method for Msg3. If the resource allocation information included in Msg2 includes index information, frequency domain resources for Msg3 transmission may be allocated / mapped in low order / high order based on the index information. Resources may be mapped sequentially from f0 to f3. Alternatively, the method of FIG. 40(a) may be applied to resources considering the R value. The resource allocation information may include index information regarding the R value. For example, if there are 4 frequency domain resources and 2, 4, and 8 16 are used with different R values, the R value can be indicated using 2 bits.

[0340] FIG. 40(d) is a repeating form of FIG. 39(a), and illustrates a method for transmitting Msg2 and Msg3 when resource mapping / allocation exceeds the structure of FIG. 40(a) based on conditions of information fields that may be included in Common-Msg2 or the configuration form of resources of Msg1. FIG. 40(d) may be a structure in which resource allocation for Msg1 supports both TDMA and FDMA simultaneously. For example, if the number of time domain resources and the number of frequency domain resources are 2 and 4, respectively, Msg3 cannot be transmitted at once with the structure of FIG. 40(a), so Msg3 can be transmitted using a structure such as FIG. 40(b) or FIG. 40(d). FIG. 40(d) may be configured such that frequency domain resources corresponding to Common-Msg2 are repeated for each time domain resource of Msg1, and the method described through FIG. 40(a) may be applied to each time domain resource.

[0341] FIG. 41 is a diagram showing the transmission relationship of Separate-Msg2 in a time domain resource and Msg3 in a frequency and time resource according to one embodiment of the present specification.

[0342] FIG. 41(a) illustrates the form in which the resources for Msg3 transmission described through FIG. 39(c) and FIG. 40(c) are extended into time-domain resources. Each Separate-Msg2 may explicitly or implicitly include resource allocation information for Msg3. The resource allocation information may be mapping / allocation information for multiple time-domain resources and multiple frequency-domain resources within each time-domain resource. Below, a method for establishing resources for Msg3 transmission based on the resource allocation information is described.

[0343] - Each of the multiple Separate-Msg2s may include information related to the time-domain resource to which the corresponding Msg3 is to be transmitted and / or information related to the frequency-domain resource. The information related to the frequency-domain resource may be index information for the SFS factor R value. Based on the index information, the frequency-domain resources may be allocated in descending / ascending order or in order of maximum separation. The information related to the time-domain may be the number of additional Msg2s transmitted after the current Msg2 (A) and the order of the slots allocated within the entire transmission time slot of the corresponding Msg3 (B). For example, referring to FIG. 41(a), A can have a value of 0 (a value included in the last Separate-Msg2, i.e., no subsequent Separate-Msg2) to 9 (a value included in the first transmitted Separate-Msg2, i.e., 9 subsequent Separate-Msg2s), and B can have a value of 0 (first slot) or 1 (second slot).

[0344] - The last transmitted Separate-Msg2 may contain information related to time-domain resources for Msg3 and / or information related to frequency-domain resources. The information related to frequency-domain resources may be index information for the SFS factor R value. Based on the index information, frequency-domain resources may be allocated in descending / ascending order or in order of maximum separation. Each device receives a Msg2 containing its own information and, after obtaining information related to the time-domain resources for Msg3 (e.g., slot allocation order, B), continuously receives Separate-Msg2 until it receives the last Separate-Msg2 (where there are no more Msg2 transmissions, or where the Separate-Msg2 contains an indicator indicating that it is the last Separate-Msg2). Then, each device may determine the transmission slot of Msg3 by applying the previously received information related to the time-domain resources for Msg3 (B) based on the last Separate-Msg2.

[0345] iii) Resources for Msg3 may be allocated / indicated / mapped at regular time intervals based on the last transmission time of Separate-Msg2. At this time, Separate-Msg2 may indicate / map / allocate a combination of information regarding relative time positions and information regarding R values. For example, if there are two time interval resources, one of them may be indicated by a 1-bit indicator (B), and index information regarding R values ​​may be indicated through additional bits. Alternatively, based on the 1-bit indicating time information, R values ​​may be mapped / allocated in descending or ascending order. At this time, each terminal is aware of the size of the total time domain resource and the end time (T_0) for which Separate-Msg2 is transmitted, and can subsequently calculate its own Msg3 transmission slot using Msg3 transmission slot information (B).

[0346] Figure 41(b) shows how Separate-Msg2 and Msg3 are transmitted in a structure that is a repetition of Figures 39(b) and 40(c).

[0347] PDRCH in FIGS. 42 to 44 may refer to an area where only data exists without ambles (data area in FIGS. 30 to 34, etc.).

[0348] FIG. 42 is a diagram showing the structure of Msg1 FDMed in CBRA (Contention-based Random access) according to one embodiment of the present specification.

[0349] Msg1 may be a response message to an R2D message (e.g., a paging message) that triggers random access. Msg1 may be transmitted via FDMA. FIG. 42 illustrates an example of resources that can be supported for the transmission of Msg1, showing a case where there is one time-domain resource and two frequency-domain resources. The message transmitted by the device to the reader may consist of a D2R preamble, PDRCH, one or more midambles, and a final midamble (postamble). The D2R preamble may be generated based on an M sequence. As described above, the period of the M sequence may be 2^n-1. If n is 5, the sequence may be a 31-bit sequence (long length), and if n is 3, the sequence may be a 7-bit sequence (short length). PDRCH may represent data sent by the device and may be generated in the manner shown in FIG. 42(c). The basic information to be sent by the device may have CRCs of different lengths added depending on the conditions, and Data+CRC may be repeated in blocks. Channel coding may be applied to the information repeated in blocks. When channel coding is applied, the constraint length (e.g., 7) and coding rate (e.g., 1 / 3 or 1 / 2, etc.) of the TBCC (tail biting convolutional code) may be applied. The coding rate may also be 1 / 2. The midamble may use the same sequence as the preamble. In this case, the sequence may be a 7-bit sequence or a 31-bit sequence. When a midamble is used, it may be added at regular interval bits. In particular, the midamble may be located at the end of the PDRCH, and the reader may indicate to the device whether the midamble is located at the end of the PDRCH through a 1-bit indicator.For example, if the value of the indicator is 1, a midamble is located at the end of the PDRCH, and if the value of the indicator is 0, a midamble may not be located at the end of the PDRCH. In this specification, the midamble located at the end of the PDRCH may be described as a postamble or as an additional midamble. 1 may indicate application, 0 may indicate non-application, or vice versa.

[0350] FIG. 42(a) illustrates an example where a midamble is not located at the end of the PDRCH. FIG. 42(b) illustrates an example where a midamble is located at the end of the PDRCH. When Msg1 is transmitted via FDMA, the data size may need to be identical for each device to maintain the same data rate. If the data size is identical, the CRC size, number of block repetitions, channel coding status, preamble length, midamble length, and interval bits related to the spacing between midambles may need to be identical. Additionally, the time length for transmitting 1 bit may also need to be identical. Furthermore, whether a final midamble exists may also need to be identical.

[0351] FIG. 43 is a diagram showing Msg1 transmitted in a plurality of time and frequency domain resources in a CBRA according to one embodiment of the present specification.

[0352] FIG. 43 illustrates an example of resources for transmitting Msg1, where there may be 2 time domain resources (X=2) and 2 frequency domain resources. If the FDM devices do not maintain the same data rate, the devices may operate based on incorrect standards in terms of time relationships. Referring to FIG. 43, when X is 2, the device may need to transmit Msg1 at the time of Toffset1 + Toffset2. Toffset2 can be calculated as ax Toffset1 + bx Tmsg1, where a is 0.25, b is 1.25, and Tmsg1 is the time domain transmission period of Msg1 when X is 1. If the presence or absence of a midamble located at the end of the PDRCH varies for each FDM Msg1, the Tmsg1 calculated by each device may differ from one another. If the same data rate is not maintained in Msg1 when X is 2, the time reference point for monitoring R2D Msg2 may be different, and each device may perform different actions at different points in time. Therefore, the data rate may need to be the same for each device.

[0353] FIG. 44 is a diagram showing a structure in which Msg1 and Msg3 are FDM-transmitted according to one embodiment of the present specification.

[0354] Referring to Fig. 44, Msg3 can also be transmitted via FDM just like Msg1. Additionally, each device can maintain the same data rate for Msg3 transmission. To maintain the same data rate, the conditions applied in Msg1 may need to be set identically in the parameters for Msg3.

[0355] When Msg1 and Msg3 are transmitted via FDM, each device must maintain the same data rate. To achieve this, common conditions / parameters can be commonly instructed to the devices through paging messages, paging-like messages, R2D messages immediately preceding D2R, etc.

[0356] Alternatively, the resources for the transmission of Msg1 and Msg3 may be set to different parameters. Msg3 may transmit more data than Msg1. A 1-bit indicator indicating that conditions / parameters apply commonly to devices transmitting Msg1 and Msg3 in the FDM method may be added to the R2D message immediately preceding the paging, paging-like message, Msg2 or D2R message providing resource allocation information for the transmission of Msg3. It may indicate that 1 is common and 0 is not common.

[0357] FIG. 45 is a diagram showing a frame structure that can be considered during R2D transmission according to one embodiment of the present specification.

[0358] The frame structure for R2D transmission may be similar to the frame structure of a conventional NR OFDM system. This is to allow the base station to use the functions of conventional OFDM transmission to minimize interference with the conventional NR OFDM communication system and to coexist in adjacent bands. FIG. 45(a) shows a frame structure where the subcarrier spacing (SCS) is 15KHz and one slot consists of 14 OFDM symbols. The frame structure may be composed of a repeating form of Cyclic Prefix (CP) + OFDM symbol. Symbols may be indexed with indices from 0 to 13. Symbol indices 0 and 7 use a long CP, the length is 5.208 usec, and the CP length + OFDM symbol length (66.667 usec) may be 71.875 usec. For the remaining symbols (excluding index 0 and 7 symbols), a normal CP is used, with a length of 4.688 usec, and the CP length + OFDM symbol length can be 71.354 usec. If the clock frequency of the AIoT system is 1.92 MHz, the long CP interval may contain 10 samples, the normal CP interval may contain 9 samples, and the single OFDM symbol interval excluding the CP may contain 128 samples. In an AIoT system using Manchester coding and OOK modulation, the number of chips that can be included in a single OFDM symbol can be determined by the M value of the Manchester coding. Fig. 45(b) shows a single OFDM symbol composed of one chip when the M value is 1. Fig. 45(c) shows a single OFDM symbol composed of two chips when the M value is 2. Fig. 45(d) shows a single OFDM symbol composed of four chips when the M value is 4. At this time, the 9 or 10 sample signals included in the CP interval can be configured by copying 9 or 10 sample signal values ​​based on the last sample signal of the last chip value of the OFDM symbol.

[0359] The method for configuring and removing CP, which is essential for coexistence with OFDM systems in OOK-style R2D transmission, may be as follows. Hereinafter, this may be referred to as the CP configuration / removal method.

[0360] Method 1 - The transmitting side (e.g., reader) can remove the CP from the receiving device without separate instructions.

[0361] Method 1-1: The receiving device can remove the CP by assuming that the CP length added to each OFDM symbol is the same.

[0362] Method 1-2: The receiving device measures the interval based on the transition edge and can identify the part where a different chip length occurs based on the already known chip length. Then, the receiving device can determine the part where a different chip length occurs as the CP length or CP location.

[0363] Method 2 - When a CP is added to an OFDM-based waveform, it may be a method that does not generate a false rising / falling edge between the last OOK chip of the n-1th OFDM symbol and the first OOK chip of the nth OFDM symbol.

[0364] Method 2-1: This may be a method that maintains subcarrier orthogonality.

[0365] - i) To maintain subcarrier orthogonality, the last OOK chip of the OFDM symbol can have the same signal state as the first OOK chip.

[0366] - ii) To maintain subcarrier orthogonality, transition edges can be configured to occur only at the beginning or only at the end of the CP. Also, transition edges can be configured not to occur within the CP interval.

[0367] Method 2-2: This may be a method that does not maintain subcarrier orthogonality. It may be a method that copies the CP at a location other than the end of the OFDM symbol.

[0368] When M chips per OFDM symbol are considered in Method 2, the chip length of OOK-4 can be configured as follows. M chips can be configured considering the length of an OFDM symbol including a CP. M chips can be configured considering the length of an OFDM symbol not including a CP.

[0369] FIG. 46 is a diagram illustrating a method of applying different M values ​​in an R2D frame structure according to one embodiment of the present specification.

[0370] FIG. 46(a) shows a single OFDM symbol composed of 6 chips when M is 6. FIG. 46(b) shows a single OFDM symbol composed of 8 chips when M is 8. FIG. 46(c) shows a single OFDM symbol composed of 12 chips when M is 12. FIG. 46(d) shows a single OFDM symbol composed of 16 chips when M is 16. FIG. 46(e) shows a single OFDM symbol composed of 24 chips when M is 24. FIG. 46(f) shows a single OFDM symbol composed of 32 chips when M is 32.

[0371] If the value of M is 16 or greater, the CP length may be greater than the length of a single chip. For example, the normal length range judged as a single chip may be [0.5*T, 1.5*T]. Here, T may be the chip length. Therefore, if the value of M is 8 or greater, the sum of the CP length and the chip length becomes 25 or 26 samples, which may exceed 24 samples, the maximum length of the normal range (1.5*T). In this case, it may be difficult for the receiving device to detect the CP section, making it difficult to remove the CP. That is, the receiving device cannot distinguish whether the received sample is for two consecutive chips or a CP, which may degrade the performance of the receiving system.

[0372] Additionally, depending on the value of M, the chip lengths included in a single OFDM symbol may differ. FIGS. 46(b), (d), and (f) illustrate cases where the chip length within a symbol is uniform, while FIGS. 46(a), (c), and (e) illustrate cases where the chip length within a symbol is non-uniform. When the chip length is non-uniform, it may be configured to differ by up to +1 or -1 sample size for each chip length. Alternatively, the chip length may be limited to a reference sample size. The reference sample size may be a positive integer. Referring to FIG. 46(a), the two last chips may be configured to be one sample larger. Referring to FIG. 46(c), the four last chips may be configured to be one sample smaller. Referring to FIG. 46(e), the eight last chips may be configured to be one sample larger. Referring to FIG. 46(d), if the value of M is 16, the chip length may be configured uniformly, but the last chip length may be adjusted to be equal to the CP length to maintain the same CP length and the last chip length of the OFDM symbol. Considering the maximum CP length as 10, the last chip length can be adjusted to 10, and the lengths of the two chips immediately preceding it can be adjusted to decrease in size by one sample from 8 to 7. In FIGS. 46(d), (e), and (f), unnecessary edges may occur within the CP section because the chip length is shorter than the CP length.

[0373] FIGS. 47 to 50 are drawings illustrating a method of configuring CP.

[0374] The value M may represent the number of OOK-4 coding chips that can be included in a single OFDM symbol. The length of CP may be determined by the system configuration. For example, if the length of a single OFDM symbol is 128 sample lengths, the CP length may be 9 or 10 sample lengths.

[0375] FIG. 47 shows a method for configuring CP when the value of M is 1. By configuring CP using methods other than the CP configuration / removal method 2-2 described above through FIG. 45, the conditions for easy removal of CP when the device receives it can be satisfied.

[0376] FIG. 48 illustrates a method for configuring a CP when the value of M is 2. FIG. 48 illustrates the structure when a CP is configured while maintaining the state of the chip and subcarrier orthogonality that may occur between symbols. In the signal patterns of FIG. 48(a) and (c), all conditions can be satisfied except for the CP configuration / removal method 2-2 described above through FIG. 45. In the signal patterns of FIG. 48(b) and (d), edges may occur both before and after the CP section, so condition ii) of the CP configuration removal / method 2-1 described above through FIG. 45 may not be satisfied.

[0377] Figure 49 shows how to configure CP when the M value is 4.

[0378] In configuring the CP, a parity chip may be considered. In FIG. 48(b) and (d), the last chip within the OFDM symbol may be set as a parity chip and may be configured to the same level / state as the first chip of the OFDM symbol (or the last chip of the previous OFDM symbol).

[0379] Referring to Fig. 49(b), the last chip of the last OFDM symbol can be configured as a parity chip and can be configured to the same level / state as the first chip of the OFDM symbol. The CP can be configured by copying the last samples (9 or 10) of the parity chip. In this case, the CP and the first chip of the OFDM symbol can be configured to the same level / state (refer to the dotted line section of Fig. 49(b). This allows edges to not occur before and after the CP section. In this case, although the M value is 4, the OFDM symbol may have a structure that includes three chips related to source bits / information and one special parity chip. With the addition of one parity chip, the overhead may be 25% per symbol, and additional symbols may be required to transmit data.

[0380] Figure 50 shows a method for configuring CP when the M value is 4.

[0381] In configuring the CP, parity chips and padding chips can be considered.

[0382] The source bit and CRC bit are coded in Manchester and can be divided into OFDM symbols and transmitted based on the M value. In this case, depending on the M value, a missing chip may occur in the last OFDM symbol. In this case, the missing chip can be filled with padding chips. The method of filling with padding chips can be determined based on whether to add parity chips, taking into account the aforementioned CP configuration / removal method.

[0383] FIG. 50(a) shows the structure of a symbol in which the signal value of the last chip is configured as the signal value of the parity chip, considering the CP configuration. In this case, one or two padding chips may be generated. FIG. 50(b) and (c) show a symbol configuration including two information chips, one padding chip, and one parity chip. The level / state of the padding chip can be set to the same level / state as the parity chip, and accordingly, the receiving device can distinguish the padding chip. FIG. 50(d) and (e) show a symbol configuration including one information chip, two padding chips, and one parity chip. The level / state of the padding chip can be set to the same level / state as the parity chip. Alternatively, the level / state of the padding chip can be configured in a structure in which an edge is generated in a 10 / 01 pattern starting from the level / state of the information chip. 5041 in FIG. 50(d) and 5052 in FIG. 50(e) represent an example of configuring a padding chip at the same level / state as the parity chip. 5042 in FIG. 50(d) and 5051 in FIG. 50(e) represent the structure of a padding chip that starts in the same state as the previous information chip. In this case, referring to 5042 in FIG. 50(d), the padding chip can be configured in a 10 / 01 pattern, and 5051 in FIG. 50(e) can be configured in an 01 / 10 pattern.

[0384] PDRCH in FIGS. 51 and 52 may refer to an area where only data exists without ambles (data area in FIGS. 30 to 34, etc.).

[0385] FIGS. 51 and FIGS. 52 are drawings showing the channel structure of an R2D transmission according to one embodiment of the present specification.

[0386] Referring to FIG. 51, the R2D transmission is a message transmitted by the reader to the device and can be composed of a combination of a preamble, PRDCH, and postamble. The postamble can perform the function of informing the device of the last position of the PRDCH. The postamble can be transmitted immediately following the PRDCH. The postamble can be configured in a way that breaks the Manchester coding rule. For example, the postamble can be composed of two consecutive chips of the same level or three or more consecutive chips of the same level. FIG. 51 shows the chip configuration when the M value of the last OFDM symbol is 6. Depending on the M value, the last OFDM symbol may contain only the postamble, or it may include chip information corresponding to the data information of the PRDCH, padding chip information, and chip information of the postamble.

[0387] Figure 52 is a diagram showing the information chip, padding chip, and postamble chip within the last OFDM symbol in the channel structure of R2D transmission.

[0388] Referring to FIG. 52, the last OFDM symbol may consist of three consecutive chips, and there may be one post-amble and padding chip having the same level. The chip level of the post-amble may be configured to be the same as the first chip level of the OFDM symbol. In this case, the CP may be configured based on the chip of the last post-amble and may be configured to be the same level as the first chip of the OFDM symbol.

[0389] A single R2D OFDM symbol can be composed of M chips based on the value of M. If the value of M is 1, a single OFDM symbol can be composed of one chip, and if the value of M is 2, an OFDM symbol can be composed of two chips.

[0390] If the value of M is 2, the postamble is composed of two chips and can be configured at the same level as the first chip level of the OFDM symbol. For example, the postamble can be composed of 11 or 00. In this case, one OFDM symbol is set as the postamble chip and the CP can be configured based on the last chip level.

[0391] If the value of M is 4, the postamble is composed of two chips and can be configured at the same level as the first chip level of the OFDM symbol. For example, the postamble can be composed of 11 or 00. In this case, if padding is required, the padding chips can be configured at the same chip level as the postamble. The chip level of the postamble can be set to be the same as the first chip level of the OFDM symbol. Alternatively, the chip level of the postamble can be set to be the same as the last chip level of the OFDM symbol.

[0392] If the value of M is 6, the postamble can be 2 chips or 4 chips. Additionally, the postamble can be composed entirely of 1s or 0s. Furthermore, if padding is required, the padding chip level can be configured to be equal to the chip level of the postamble. The chip level of the postamble can be set to be equal to the first chip level of the OFDM symbol. Alternatively, the chip level of the postamble can be set to be equal to the last chip level of the OFDM symbol. Even when the value of M is greater than 6, the postamble and padding chips can be configured in the same way as when the value of M is 6.

[0393] FIG. 53 is a diagram showing a case where there are two time domain resources supporting TDMA according to one embodiment of the present specification.

[0394] FIG. 53 illustrates a case where there are two time-domain resources supporting TDMA, but the number of time-domain resources may be two or more. Msg1 may be a response message to a paging message transmitted by the device to the reader. Since the device may have an SFO, the time-domain resource for transmitting Msg1 may require a guard time that takes the SFO into account. Referring to FIG. 53(a), the guard time for each time-domain resource may be the same. If the information size of Msg1 is the same and the guard time is the same, the size of each time-domain resource may be the same. FIG. 53(b) shows the size of the transmission bandwidth for D2R set as a multiple of 15 kHz and the base chip length corresponding to the size of each transmission bandwidth. As the transmission bandwidth increases, the base chip length may decrease. Therefore, as the transmission bandwidth increases, the time to transmit Msg1 decreases, and thus the guard time may also decrease. The guard time may be set based on the base chip length of the transmission bandwidth. As the transmission bandwidth increases, the guard time may decrease. For example, as the transmission bandwidth increases by a factor of N, the guard time can be reduced by a factor of 1 / N. Specifically, the guard time when the transmission bandwidth is the smallest at 15 kHz is T TxBW15 In this case, when the bandwidth is 30kHz, the guard time is half of the guard time when it is 15kHz (T TxBW15 It can be reduced to / 2. Alternatively, the guard time can be reduced by a constant rate based on a constant offset. The guard time can be applied to both Msg1 transmission and D2R transmission using TDMA.

[0395] FIG. 54 illustrates a method for performing wireless communication according to one embodiment of the present specification.

[0396] Referring to FIG. 54, a method for performing wireless communication between a device and a reader as described in FIG. 1 to FIG. 53 will be explained.

[0397] The device can receive information related to the PDRCH (physical device-to-reader channel) (S5410).

[0398] The above information may include an indicator indicating whether there is an additional mid-ampl at the very end of the above PDRCH.

[0399] The device can transmit the PDRCH configured based on the above information (S5420).

[0400] If the above indicator indicates that an additional mid-ampl exists at the very end of the above PDRCH, the additional mid-ampl may be located at the very end of the above PDRCH.

[0401] The above indicator may be 1 bit in size.

[0402] The above PDRCH may include a preamble and a midamble.

[0403] The sequence of the preamble, the sequence of the midamble, and the sequence of the additional midamble may all be the same specific sequence.

[0404] A device composed of the above specific sequence of 0s and 1s, configured such that there is one more 1 than 0.

[0405] The length of the specific sequence above may be 7 or 31.

[0406] If the length of the specific sequence above is 7, the initial value of the specific sequence above may be 1 0 0.

[0407] The above mid-amplifiers can be positioned at equal intervals.

[0408] The above information may include a small frequency shift (SFS) factor value (R).

[0409] If R is greater than 1, the transmission time of the PDRCH may be 1 / R of the transmission time when R is 1.

[0410] If R is greater than 1, the PDRCH can be repeated R times during the transmission time when R is 1.

[0411] The above PDRCH can be repeated in a form where the value mapped by the OOK (On-off keying) modulation method is repeated.

[0412] The above information may include information regarding the TBS (transport block size) of the above PDRCH.

[0413] The above wireless communication system may be an A-IoT (ambient-internet of things) system.

[0414] The device may be configured to include a communication module for transmitting and receiving wireless signals and a processor for controlling the communication module.

[0415] 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.

[0416] 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.

[0417] 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

1. 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, Receives information related to the PDRCH (physical device-to-reader channel), and The above information includes an indicator that indicates whether there is an additional midamble at the very end of the above PDRCH, and Transmit the above PDRCH configured based on the above information, and A device in which, if the above indicator indicates that an additional mid-ampl exists at the very end of the PDRCH, the additional mid-ampl is located at the very end of the PDRCH.

2. In Paragraph 1, The above indicator is a device of 1 bit size.

3. In Paragraph 1, The above PDRCH includes a preamble and a midamble, and A device in which the sequence of the preamble, the sequence of the midamble, and the sequence of the additional midamble are all the same specific sequence.

4. In Paragraph 3, A device composed of the above specific sequence of 0s and 1s, configured such that there is one more 1 than 0.

5. In Paragraph 3, A device in which the length of the specific sequence above is 7 or 31.

6. In Paragraph 5, If the length of the above specific sequence is 7, A device in which the initial value of the specific sequence above is 1 0 0.

7. In Paragraph 3, The above mid-amplifier is a device positioned at equal intervals.

8. In Paragraph 1, The above information includes the SFS (small frequency shift) factor value (R), and A device in which, if R is greater than 1, the transmission time of the PDRCH is 1 / R of the transmission time when R is 1.

9. In Paragraph 8, A device in which, if R is greater than 1, the PDRCH is repeated R times during the transmission time when R is 1.

10. In Paragraph 9, The above PDRCH is a repeating device in the form of a value mapped by the OOK (On-off keying) modulation method.

11. In Paragraph 1, The above information is a device that includes information about the TBS (transport block size) of the PDRCH.

12. In Paragraph 1, The above wireless communication system is a device that is an A-IoT (ambient-internet of things) system.

13. In a wireless communication system, the method performed by the device is, A step of receiving information related to the PDRCH (physical device-to-reader channel), The above information includes an indicator indicating whether there is an additional midamble at the very end of the above PDRCH; and It includes the step of transmitting the PDRCH configured based on the above information, and A method in which, when the above indicator indicates that there is an additional mid-ampl at the very end of the above PDRCH, the additional mid-ampl is located at the very end of the above PDRCH.

14. In Paragraph 13, The above indicator is a method of 1 bit size.

15. In Paragraph 13, The above PDRCH includes a preamble and a midamble, and A method in which the sequence of the preamble, the sequence of the midamble, and the sequence of the additional midamble are all the same specific sequence.

16. In Paragraph 15, A method composed of the above specific sequence of 0s and 1s, configured such that there is one more 1 than 0.

17. In Paragraph 15, A method in which the length of the specific sequence above is 7 or 31.

18. In Paragraph 17, If the length of the above specific sequence is 7, A method in which the initial value of the specific sequence above is 1 0 0.

19. In Paragraph 15, The above mid-amplifiers are positioned at equal intervals.

20. In Paragraph 13, The above information includes the SFS (small frequency shift) factor value (R), and A method in which, if R is greater than 1, the transmission time of the PDRCH is 1 / R of the transmission time when R is 1.

Images