Method and apparatus for transmitting and receiving data in wireless network

Abstract

The present embodiment relates to a method and apparatus for transmitting and receiving data in a wireless network, and provides a method by which a terminal transmits data, comprising: receiving configuration information for periodic transmission of an uplink data channel from a base station; and transmitting an uplink data channel to the base station on the basis of the configuration information, wherein the terminal is a terminal supporting an augmented reality service.

Description

Technical Field

[0001] The present embodiment proposes a method and apparatus for performing data transmission / reception in a radio network in a next generation radio access network (hereinafter referred to as "new radio (NR)"). Background Art

[0002] Recently, the 3rd generation partnership project (3GPP) has approved "Study on New Radio Access Technology", which is a research project for exploring the next generation / 5G radio access technology (hereinafter referred to as "new radio" or "NR"). Based on the research on new radio access technology, the Radio Access Network Working Group 1 (RAN WG1) has been discussing the frame structure, channel coding and modulation, waveform, and multiple access method for the new radio (NR). Designing NR not only needs to provide improved data transmission rates compared to long term evolution (LTE) / LTE-Advanced, but also needs to meet various requirements in detailed and specific usage scenarios.

[0003] Enhanced mobile broadband (eMBB), massive machine-type communication (mMTC) and ultra-reliable and low-latency communication (URLLC) are proposed as typical use cases for NR. In order to meet the requirements of each scenario, NR needs to be designed with a flexible frame structure compared to LTE / LTE-Advanced.

[0004] Due to the different requirements for data rate, latency, reliability, and coverage, a method is needed to efficiently reuse radio resources based on different numerologies (e.g., subcarrier spacing, subframes, and transmission time intervals (TTI)). This meets the requirements for each usage scenario within the frequency band of the NR system.

[0005] A specific design is needed that can efficiently handle resource allocation and scheduling during data transmission and reception on UEs supporting extended reality (XR) services in wireless networks. Summary of the invention

[0006] Technical issues

[0007] The present disclosure may provide a method and apparatus for performing data transmission and reception in a wireless network in NR.

[0008] Technical Solutions

[0009] In one aspect, the present disclosure may provide a method for transmitting data by a user equipment (UE). The method may include: receiving configuration information about periodic transmission of an uplink data channel from a base station; and transmitting the uplink data channel to the base station based on the configuration information. The UE supports extended reality (XR) services.

[0010] In another aspect, the present disclosure may provide a method for receiving data by a base station. The method may include: transmitting configuration information about periodic transmission of an uplink data channel to a UE; and receiving an uplink data channel from the UE based on the configuration information. The UE supports an extended reality (XR) service.

[0011] In another aspect, the present disclosure may provide a UE for transmitting data. The UE may include a transmitter, a receiver, and a controller that controls the operation of the transmitter and the receiver, receives configuration information about periodic transmission of an uplink data channel, and transmits the uplink data channel based on the configuration information, wherein the UE supports an extended reality (XR) service.

[0012] In another aspect, the present disclosure may provide a base station for receiving data. The base station may include a transmitter, a receiver, and a controller, the controller controlling the operation of the transmitter and the receiver, transmitting configuration information about periodic transmission of an uplink data channel to a UE, and receiving the uplink data channel based on the configuration information, wherein the UE supports an extended reality (XR) service.

[0013] Technical Effects

[0014] According to this embodiment, data can be efficiently transmitted and received in a wireless network in NR. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is a diagram schematically illustrating an NR wireless communication system according to an embodiment of the present disclosure;

[0016] Figure 2 is a view schematically showing a frame structure in an NR system according to an embodiment of the present disclosure;

[0017] Figure 3 is a view for explaining a resource grid supported by a radio access technology according to an embodiment of the present disclosure;

[0018] Figure 4is a view for explaining a bandwidth portion supported by a radio access technology according to an embodiment of the present disclosure;

[0019] Figure 5 is a view showing an example of a synchronization signal block in a radio access technology according to an embodiment of the present disclosure;

[0020] Figure 6 is a signal diagram for explaining a random access procedure in a radio access technology according to an embodiment of the present disclosure;

[0021] Figure 7 It is a view used to explain CORESET;

[0022] Figure 8 is a diagram showing an example of symbol-level alignment in different subcarrier spacings (SCS) according to an embodiment of the present disclosure;

[0023] Fig. 9 is a diagram schematically showing a bandwidth portion to which an embodiment of the present disclosure can be applied;

[0024] Fig.10 is a flow chart illustrating a method for controlling transmission of an uplink data channel by a UE according to an embodiment;

[0025] Fig.11 is a flow chart illustrating a method for controlling reception of an uplink data channel by a base station according to an embodiment;

[0026] Fig.12 is a block diagram showing a UE according to an embodiment; and

[0027] Fig.13 is a block diagram showing a base station according to an embodiment. DETAILED DESCRIPTION

[0028] Hereinafter, some embodiments of the present disclosure will be described in detail with reference to the illustrative drawings. In the accompanying drawings, the same reference numerals are used to refer to the same elements throughout the drawings, even if they are shown in different drawings. In addition, in the following description of the present disclosure, if the detailed description of the known functions and configurations incorporated herein may make the subject matter of the present disclosure unclear, it will be omitted. When using the expressions "including", "having" or "comprising" etc. as mentioned herein, any other parts can be added unless the expression "only" is used. When an element is expressed in the singular, the element can cover the plural form unless the element is explicitly mentioned in particular.

[0029] In addition, terms such as first, second, A, B, (A) or (B) etc. may be used herein when describing components of the present disclosure. Each of these terms is not used to define the nature, order or sequence of the corresponding components, but is only used to distinguish the corresponding components from other components.

[0030] In describing the positional relationship between components, if two or more components are described as being "connected," "combined," or "coupled" to each other, it should be understood that the two or more components may be directly "connected," "combined," or "coupled" to each other, and the two or more components may be "connected," "combined," or "coupled" to each other with another component "interposed" therebetween. In this case, the other component may be included in at least one of the two or more components that are "connected," "combined," or "coupled" to each other.

[0031] In the description of a series of operating methods or manufacturing methods, for example, the use of expressions such as "after", "subsequently", "next" and "before" may also cover the case where the operations or processes are not performed continuously, unless "immediately" or "directly" is used in the expression.

[0032] Numerical values ​​mentioned herein for components or information corresponding thereto (e.g., levels, etc.) may be construed as including an error range caused by various factors (e.g., process factors, internal or external influences, noise, etc.) even if no explicit description is provided therefor.

[0033] The wireless communication system in this specification refers to a system for providing various communication services such as voice services and data services using radio resources. The wireless communication system may include user equipment (UE), base stations, and a core network.

[0034] The embodiments disclosed below can be applied to wireless communication systems using various radio access technologies. For example, the embodiments can be applied to various radio access technologies, such as code division multiple access (CDMA), frequency division multiple access (FDMA), time division multiple access (TDMA), orthogonal frequency division multiple access (OFDMA), single carrier frequency division multiple access (SC-FDMA), or non-orthogonal multiple access (NOMA), etc. In addition, radio access technology can refer to various generations of communication technologies established by various communication organizations (such as 3GPP, 3GPP2, WiFi, Bluetooth, IEEE or ITU, etc.), as well as specific access technologies. For example, CDMA can be implemented as a wireless technology such as Universal Terrestrial Radio Access (UTRA) or CDMA2000. TDMA can be implemented as a wireless technology such as Global System for Mobile Communications (GSM) / General Packet Radio Service (GPRS) / Enhanced Data Rate for GSM Evolution (EDGE). OFDMA can be implemented as a wireless technology such as IEEE (Institute of Electrical and Electronics Engineers) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802-20, Evolved UTRA (E-UTRA). IEEE 802.16m is an evolution of IEEE 802.16e, which provides backward compatibility with systems based on IEEE802.16e. UTRA is part of the Universal Mobile Telecommunications System (UMTS). 3GPP (3rd Generation Partnership Project) LTE (Long Term Evolution) is a part of E-UMTS (Evolved UMTS) using Evolved UMTS Terrestrial Radio Access (E-UTRA), which adopts OFDMA in the downlink and SC-FDMA in the uplink. As described above, the embodiments can be applied to radio access technologies that have been enabled or commercialized, and can be applied to radio access technologies that are being developed or will be developed in the future.

[0035] The UE used in this specification must be interpreted in a broad sense, indicating a device including a wireless communication module that communicates with a base station in a wireless communication system. For example, the UE includes user equipment (UE) in WCDMA, LTE, NR, HSPA, IMT-2020 (5G or new air interface), etc., a mobile station in GSM, a user terminal (UT), a subscriber station (SS), and a wireless device, etc. In addition, the UE can be a portable user device, such as a smart phone, or it can be a vehicle in a V2X communication system, a device containing a wireless communication module in the vehicle, etc. (depending on its type of use). In the case of a machine type communication (MTC) system, the UE can refer to an MTC terminal, an M2M terminal, or a URLLC terminal, which uses a communication module capable of performing machine type communication.

[0036] A base station or cell in this specification refers to an endpoint that communicates with a UE through a network, and covers various coverage areas, such as Node-B, evolved Node-B (eNB), gNode-B, low power node (LPN), sector, site, various types of antennas, base transceiver system (BTS), access point, point (e.g., transmission point, reception point or transmission / reception point), relay node, megacell, macrocell, microcell, picocell, femtocell, remote radio head (RRH), radio unit (RU), and small cell, etc. In addition, a cell may be used as a meaning including a bandwidth part (BWP) in the frequency domain. For example, a serving cell may refer to an active BWP of a UE.

[0037] The various cells listed above are provided with a base station that controls one or more cells, and the base station can be interpreted as the following two meanings. The base station can be 1) a device for providing a megacell, macrocell, microcell, picocell, femtocell or small cell connected to a wireless area, or the base station can be 2) the wireless area itself. In the above description 1), the base station can be a plurality of devices that are controlled by the same entity and provide a predetermined wireless area, or all devices that interact with each other and configure the wireless area in a coordinated manner. For example, according to the configuration method of the wireless area, the base station can be a point, a transmission / reception point, a transmission point, and a reception point, etc. In the above description 2), the base station can be a wireless area that enables a user equipment (UE) to transmit data to other UEs or adjacent base stations and receive data from them.

[0038] In this specification, a cell may refer to a coverage of a signal transmitted from a transmission / reception point, a component carrier having coverage of a signal transmitted from a transmission / reception point (or transmission point), or a transmission / reception point itself.

[0039] Uplink (UL) refers to a scheme for transmitting data from a UE to a base station, and downlink (DL) refers to a scheme for transmitting data from a base station to a UE. Downlink may mean communication or a communication path from multiple transmission / reception points to a UE, and uplink may mean communication or a communication path from a UE to multiple transmission / reception points. In the downlink, a transmitter may be part of multiple transmission / reception points, and a receiver may be part of a UE. In addition, in the uplink, a transmitter may be part of a UE, and a receiver may be part of multiple transmission / reception points.

[0040] The uplink and downlink transmit and receive control information on control channels such as the Physical Downlink Control Channel (PDCCH) and the Physical Uplink Control Channel (PUCCH). The uplink and downlink transmit and receive data on data channels such as the Physical Downlink Shared Channel (PDSCH) and the Physical Uplink Shared Channel (PUSCH). Hereinafter, the transmission and reception of signals on channels such as PUCCH, PUSCH, PDCCH, or PDSCH may be expressed as "transmitting and receiving PUCCH, PUSCH, PDCCH, or PDSCH, etc.".

[0041] For clarity, the following description will focus on 3GPP LTE / LET-A / NR (New Radio) communication systems, but the technical features of the present disclosure are not limited to the corresponding communication systems.

[0042] After studying 4G (Fourth Generation) communication technologies, 3GPP has been developing 5G (Fifth Generation) communication technologies to meet the requirements of the next generation radio access technology of ITU-R. In particular, 3GPP is developing LTE-A pro as a 5G communication technology by improving LTE-Advanced technology so that it meets the requirements of ITU-R and the new NR communication technology that is completely different from 4G communication technologies. Both LTE-A pro and NR refer to 5G communication technologies. Hereinafter, unless a specific communication technology is specified, 5G communication technologies will be described based on NR.

[0043] Considering satellites, automobiles, and new vertical fields in typical 4G LTE scenarios, etc., various operation scenarios have been defined in NR to support enhanced mobile broadband (eMBB) scenarios in terms of services; massive machine type communication (mMTC) scenarios, where UEs cross a wide area with a high UE density and thus require low data rates and asynchronous connections; and ultra-reliable low-latency (URLLC) scenarios, which require high responsiveness and reliability and support high-speed mobility.

[0044] To meet such scenarios, NR has introduced a wireless communication system that employs new waveform and frame structure technologies, low-latency technologies, ultra-high frequency band (millimeter wave) support technologies, and forward compatibility provision technologies. Specifically, the NR system has various technical changes in terms of flexibility to provide forward compatibility. The main technical features of NR will be described below with reference to the accompanying drawings.

[0045] <Overview of the NR System>

[0046] Figure 1 is a view schematically showing the NR system.

[0047] Reference Figure 1, the NR system is divided into a 5G Core Network (5GC) and an NG-RAN part. The NG-RAN includes gNBs and ng-eNBs that provide the protocol terminations of the user plane (SDAP / PDCP / RLC / MAC / PHY) and the control plane (RRC) of the user equipment (UE). Multiple gNBs or a gNB and an ng-eNB are interconnected with each other via the Xn interface. The gNBs and ng-eNBs are connected to the 5GC via the NG interface respectively. The 5GC can be configured to include an Access and Mobility Management Function (AMF) for managing the control plane, such as UE connection and mobility control functions, and a User Plane Function (UPF) for controlling user data. NR supports both frequency bands below 6 GHz (Frequency Range 1, FR1) and frequency bands equal to or greater than 6 GHz (Frequency Range 2, FR2).

[0048] A gNB refers to a base station that provides the protocol terminations of the NR user plane and control plane for the UE. An ng-eNB refers to a base station that provides the protocol terminations of the E-UTRA user plane and control plane for the UE. The base stations described in this specification should be understood to cover gNBs and ng-eNBs. However, as needed, the base station can also be used to refer to separate gNBs or ng-NBs.

[0049] <NR Waveform, Parameter Set, and Frame Structure>

[0050] NR uses the CP-OFDM waveform with a cyclic prefix for downlink transmission and uses CP-OFDM or DFT-s-OFDM for uplink transmission. OFDM technology is easy to combine with multiple-input multiple-output (MIMO) schemes and allows the use of low-complexity receivers in cases of high frequency efficiency.

[0051] Since the three scenarios described above have mutually different requirements for data rate, latency rate, coverage, etc. in NR, it is necessary to efficiently meet the requirements for each scenario on the frequency bands that make up the NR system. For this purpose, a technique for efficiently multiplexing radio resources based on multiple different parameter sets has been proposed.

[0052] In particular, the NR transmission parameter set is determined based on the subcarrier spacing and the cyclic prefix (CP). As shown in Table 1 below, "μ" is used as an exponential value of 2 to change exponentially based on 15 kHz.

[0053] [Table 1]

[0054] μ Subcarrier spacing Cyclic prefix Supporting Data Support synchronization 0 15 conventional yes yes 1 30 conventional yes yes 2 60 General, Extended yes no 3 120 conventional yes yes 4 240 conventional no yes

[0055] As shown in Table 1 above, NR can have five types of parameter sets according to the subcarrier spacing. This is different from LTE, which is one of the 4G communication technologies, in which the subcarrier spacing is fixed to 15kHz. In particular, in NR, the subcarrier spacing for data transmission is 15kHz, 30kHz, 60kHz or 120kHz, and the subcarrier spacing for synchronization signal transmission is 15kHz, 30kHz, 120kHz or 240kHz. In addition, the extended CP is only applied to the subcarrier spacing of 60kHz. A frame is defined in the frame structure in NR, the frame includes 10 subframes, each subframe has the same length of 1ms, and the frame has a length of 10ms. A frame can be divided into half frames of 5ms, and each half frame includes 5 subframes. When the subcarrier spacing is 15kHz, a subframe includes a time slot, and each time slot includes 14 OFDM symbols. Figure 2 This is a view for explaining the frame structure in the NR system. Figure 2 , one slot includes 14 OFDM symbols, which are fixed in the case of a conventional CP, but the slot length in the time domain may vary depending on the subcarrier spacing. For example, in the case of a parameter set with a subcarrier spacing of 15kHz, the slot is configured to have the same 1ms length as the subframe. On the other hand, in the case of a parameter set with a subcarrier spacing of 30kHz, the slot includes 14 OFDM symbols, but one subframe may include two slots, each having a length of 0.5ms. That is, subframes and frames may be defined using a fixed time length, and a slot may be defined as the number of symbols so that its time length varies depending on the subcarrier spacing.

[0056] NR defines the basic unit of scheduling as a time slot, and also introduces micro-time slots (or sub-time slots, or non-time slot-based scheduling) to reduce the transmission delay of the radio segment. If a wide subcarrier spacing is used, the length of a time slot is shortened inversely proportional to it, thereby reducing the transmission delay in the radio segment. Micro-time slots (or sub-time slots) are designed to efficiently support URLLC scenarios, and micro-time slots can be scheduled in 2, 4, or 7 symbol units.

[0057] In addition, unlike LTE, NR defines uplink and downlink resource allocation at the symbol level in one slot. In order to reduce HARQ delay, a slot structure that can directly transmit HARQ ACK / NACK in the transmission slot has been defined. Such a slot structure is called a "self-contained structure", which will be described.

[0058] NR is designed to support a total of 256 slot formats, and 62 of these slot formats are used in 3GPP Rel-15. In addition, NR supports a general frame structure that constitutes an FDD or TDD frame through various combinations of slots. For example, NR supports: i) a slot structure in which all symbols of the slot are configured for downlink, ii) a slot structure in which all symbols are configured for uplink, and iii) a slot structure in which downlink symbols and uplink symbols are mixed. In addition, NR supports data transmission scheduled to be allocated to one or more slots. Therefore, the base station can use the Slot Format Indicator (SFI) to notify the UE whether the slot is a downlink slot, an uplink slot, or a flexible slot. The base station can notify the slot format by using the SFI to indicate the index of a table configured by UE-specific RRC signaling. In addition, the base station can dynamically indicate the slot format through Downlink Control Information (DCI), or can statically or semi-statically indicate the slot format through RRC signaling.

[0059] <Physical Resources of NR>

[0060] Regarding the physical resources in NR, antenna ports, resource grids, resource elements, resource blocks, and bandwidth parts are considered, etc.

[0061] An antenna port is defined as inferring another channel that carries another symbol on the same antenna port from a channel that carries one symbol on the antenna port. If the large-scale characteristics of the channel that carries a symbol on an antenna port can be inferred from another channel that carries a symbol on another antenna port, then these two antenna ports can have a quasi-colocation or quasi-co-site (QC / QCL) relationship. The large-scale characteristics include at least one of delay spread, Doppler spread, frequency shift, average received power, and reception timing.

[0062] Figure 3 A resource grid supported by a radio access technology according to an embodiment of the present disclosure is shown.

[0063] Reference Figure 3 , the resource grid can exist according to the corresponding parameter set because NR supports multiple parameter sets in the same carrier. In addition, the resource grid can depend on the antenna port, subcarrier spacing, and transmission direction.

[0064] A resource block includes 12 subcarriers and is defined only in the frequency domain. In addition, a resource element includes one OFDM symbol and one subcarrier. Therefore, as Figure 3 shown, the size of a resource block can vary according to the subcarrier spacing. In addition, "Point A" which acts as a common reference point, common resource block, and virtual resource block for the resource block grid is defined in NR.

[0065] Figure 4 Shows a bandwidth part supported by a radio access technology according to an embodiment of the present disclosure.

[0066] Unlike LTE where the carrier bandwidth is fixed at 20 MHz, in NR, the maximum carrier bandwidth depends on the subcarrier spacing configured to be 50 MHz to 400 MHz. Therefore, it is not assumed that all UEs use the entire carrier bandwidth. Thus, as Figure 4 shown, in NR, a bandwidth part (BWP) can be specified within the carrier bandwidth such that a UE can use that bandwidth part. Additionally, the bandwidth part can be associated with a parameter set, can include a subset of consecutive common resource blocks, and can be dynamically activated over time. A UE has up to four bandwidth parts in each of the uplink and downlink. The UE uses the activated bandwidth part to transmit and receive data during a given time period.

[0067] In the case of paired spectrum, the uplink bandwidth part and the downlink bandwidth part are configured independently. In the case of unpaired spectrum, to prevent unnecessary frequency retuning between downlink operation and uplink operation, the downlink bandwidth part and the uplink bandwidth part are configured in pairs to share the center frequency.

[0068] <Initial Access in NR>

[0069] In NR, a UE performs a cell search and a random access procedure to access a base station and communicate with it.

[0070] Cell search is a process of synchronizing a UE with a cell of a corresponding base station by using a synchronization signal block (SSB) sent from the base station and obtaining the physical layer cell ID and system information.

[0071] Figure 5 Shows an example of a synchronization signal block in a radio access technology according to an embodiment of the present disclosure.

[0072] Referring to Figure 5 , the SSB includes a primary synchronization signal (PSS) and a secondary synchronization signal (SSS) that occupy one symbol and 127 subcarriers, and a PBCH that spans three OFDM symbols and 240 subcarriers.

[0073] The UE monitors the SSB in the time domain and the frequency domain, thereby receiving the SSB.

[0074] SSB can be transmitted up to 64 times in 5ms. Multiple SSBs are transmitted in different transmit beams within 5ms, and the UE assumes that an SSB is transmitted every 20ms based on the specific beam used for transmission for detection. The number of beams that can be used for SSB transmission in 5ms can increase as the frequency band increases. For example, up to 4 SSB beams can be transmitted in a frequency band of 3GHz or lower, and up to 8 SSB beams can be transmitted in a frequency band of 3 to 6GHz. In addition, up to 64 different beams can be used to transmit SSB in a frequency band of 6GHz or higher.

[0075] One slot includes two SSBs, and the start symbol and the number of repetitions in the slot are determined according to the subcarrier spacing as follows.

[0076] Unlike SS in a typical LTE system, SSB is not transmitted at the center frequency of the carrier bandwidth. That is, SSB can also be transmitted at a frequency other than the center of the system band, and multiple SSBs can be transmitted in the frequency domain if broadband operation is supported. Therefore, the UE monitors the SSB using a synchronization raster, which is a candidate frequency position for monitoring SSB. The carrier raster and synchronization raster are the center frequency position information of the channel newly defined in NR for initial connection, and the synchronization raster can support the UE's fast SSB search because its frequency spacing is configured wider than that of the carrier raster.

[0077] The UE can obtain the MIB on the PBCH of the SSB. The MIB (Master Information Block) includes the minimum information for the UE to receive the remaining minimum system information (RMSI) broadcast by the network. In addition, the PBCH may include information about the position of the first DM-RS symbol in the time domain, information for the UE to monitor SIB1 (for example, SIB1 parameter set information, information related to SIB1 CORESET, search space information, PDCCH related parameter information, etc.), and offset information between common resource blocks and SSBs (the absolute SSB position in the carrier is transmitted through SIB1), etc. The SIB1 parameter set information is also applied to some messages used in the random access process for the UE to access the base station after completing the cell search process. For example, the parameter set information of SIB1 can be applied to at least one of messages 1 to 4 used for the random access process.

[0078] The RMSI mentioned above may mean SIB1 (System Information Block 1), and SIB1 is broadcast periodically (e.g., 160ms) in the cell. SIB1 includes information required for the UE to perform the initial random access procedure, and SIB1 is periodically transmitted on the PDSCH. In order to receive SIB1, the UE must receive parameter set information for SIB1 transmission, and CORESET (Control Resource Set) information for scheduling SIB1 on the PBCH. The UE uses the SI-RNTI in the CORESET to identify the scheduling information for SIB1. The UE acquires SIB1 on the PDSCH according to the scheduling information. The remaining SIBs other than SIB1 may be transmitted periodically, or the remaining SIBs may be transmitted according to the request of the UE.

[0079] Figure 6 It is a view for explaining a random access procedure in a radio access technology to which the present embodiment is applicable.

[0080] refer to Figure 6 , if the cell search is completed, the UE transmits a random access preamble for random access to the base station. The random access preamble is transmitted on the PRACH. In particular, the random access preamble is periodically transmitted to the base station on the PRACH, which includes continuous radio resources in repeated specific time slots. Generally, when the UE initially accesses a cell, a contention-based random access procedure is performed, and when the UE performs random access for beam failure recovery (BFR), a non-contention-based random access procedure is performed.

[0081] The UE receives a random access response to the transmitted random access preamble. The random access response may include a random access preamble identifier (ID), an UL grant (uplink radio resources), a temporary C-RNTI (temporary cell-radio network temporary identifier), and a TAC (time alignment command). Since a random access response may include random access response information for one or more UEs, a random access preamble identifier may be included to indicate which UE the included UL grant, temporary C-RNTI, and TAC are valid for. The random access preamble identifier may be an identifier of the random access preamble received by the base station. TAC may include information for the UE to adjust uplink synchronization. The random access response may be indicated by a random access identifier on the PDCCH, that is, a random access-radio network temporary identifier (RA-RNTI).

[0082] Upon receiving a valid random access response, the UE processes the information included in the random access response and performs scheduled transmission to the base station. For example, the UE applies the TAC and stores the temporary C-RNTI. In addition, the UE transmits data stored in the UE's buffer or newly generated data to the base station using the UL grant. In this case, information for identifying the UE must be included in the data.

[0083] Finally, the UE receives a downlink message to resolve the contention.

[0084] <NR CORESET>

[0085] The downlink control channel in NR is sent in a CORESET (Control Resource Set) having a length of 1 to 3 symbols, and the downlink control channel transmits uplink / downlink scheduling information, SFI (Slot Format Index) and TPC (Transmit Power Control) information, etc.

[0086] As described above, NR has introduced the concept of CORESET to ensure the flexibility of the system. CORESET (Control Resource Set) refers to the time-frequency resources used for downlink control signals. The UE can use one or more search spaces in the CORESET time-frequency resources to decode the control channel candidates. The CORESET specific QCL (quasi co-location) assumption is configured and used to provide information about the simulated beam direction, as well as the characteristics of delay spread, Doppler spread, Doppler shift and average delay, which are all characteristics assumed by the existing QCL.

[0087] Figure 7 A CORESET is shown.

[0088] refer to Figure 7 , CORESET can exist in various forms within the carrier bandwidth within a single time slot, and CORESET can include up to 3 OFDM symbols in the time domain. In addition, CORESET is defined in the frequency domain as a multiple of 6 resource blocks up to the carrier bandwidth.

[0089] The first CORESET, as part of the initial bandwidth portion, is designated (eg, indicated, allocated) through the MIB to receive additional configuration information and system information from the network. After establishing a connection with the base station, the UE may receive and configure one or more CORESET information through RRC signaling.

[0090] In this specification, frequency, frame, subframe, resource, resource block, area, band, subband, control channel, data channel, synchronization signal, various reference signals related to NR (New Radio), various signals, or various messages may be interpreted as the meanings currently or in the past, or as various meanings to be used in the future.

[0091] NR (New Radio)

[0092] Compared with LTE / LTE-Advanced, NR is designed to provide not only improved data transmission rates, but also to meet various QoS requirements for each detailed and specific usage scenario. Specifically, enhanced mobile broadband (eMBB), massive machine type communications (mMTC), and ultra-reliable low latency communications (URLLC) are defined as representative usage scenarios for NR. In order to meet the requirements of each scenario, NR needs to be designed with a flexible frame structure compared with LTE / LTE-Advanced.

[0093] Since each usage scenario imposes different requirements on data rate, latency, coverage, etc., a method for efficiently multiplexing radio resource units based on different parameter sets (e.g., subcarrier spacing (SCS), subframe, transmission time interval (TTI), etc.) is needed as a solution for efficiently meeting the requirements of different usage scenarios on the frequency band provided to the NR system.

[0094] To this end, i) a method of multiplexing parameter sets with mutually different subcarrier spacings (SCS) based on TDM, FDM or TDM / FDM on one NR carrier, and ii) a method of supporting one or more time units when configuring a scheduling unit in the time domain have been discussed. In this regard, in NR, the definition of a subframe has been given as a type of time domain structure. In addition, as a reference parameter set for defining the duration of a corresponding subframe, similar to LTE, a single subframe duration is defined as 14 OFDM symbols with a conventional CP overhead based on a 15kHz subcarrier spacing (SCS). Therefore, the subframe of NR has a duration of 1ms. Unlike LTE, since the subframe of NR is an absolute reference duration, time slots and microslots can be defined as time units for actual UL / DL data scheduling. In this case, the number of OFDM symbols constituting the time slot (the value of y) is defined as y=14, regardless of the parameter set.

[0095] Therefore, a slot may be composed of 14 symbols. Depending on the transmission direction of the corresponding slot, all symbols may be used for DL ​​transmission or UL transmission, or the symbols may be used in a configuration of DL part + slot + UL part.

[0096] In addition, the mini-slot has been defined to consist of fewer symbols than the slot in the parameter set (or SCS), and as a result, a short time domain scheduling interval can be configured for UL / DL data transmission or reception based on the mini-slot. Moreover, a long time domain scheduling interval can be configured for UL / DL data transmission or reception through slot aggregation.

[0097] In particular, in the case of transmission or reception of delay-critical data (such as URLLC), it may be difficult to meet the delay requirements when scheduling is performed on a time slot basis of 1 ms (14 symbols) defined in a frame structure based on a parameter set with a small SCS value (e.g., 15 kHz). To this end, a micro-time slot consisting of fewer OFDM symbols than the time slot can be defined, and thus scheduling for delay-critical data (such as URLLC) can be performed based on the micro-time slot.

[0098] As described above, it is also considered to support parameter sets with different SCS values ​​in one NR carrier by multiplexing in TDM and / or FDM manner, so as to schedule data according to the latency requirement based on the length of the time slot (or mini-time slot) defined by the parameter set. Figure 8 As shown, when the SCS is 60kHz, the symbol length is reduced to 1 / 4 of the symbol length when the SCS is 15kHz. Therefore, when a time slot is composed of 14 OFDM symbols, the time slot length based on 15kHz is 1ms, while the time slot length based on 60kHz is reduced to about 0.25ms.

[0099] Therefore, since SCS or TTI lengths different from each other are defined in NR, a technology for satisfying the requirements of each of URLLC and eMBB has been developed.

[0100] Wider bandwidth operation

[0101] A typical LTE system supports scalable bandwidth operation for any LTE CC (component carrier). That is, depending on the frequency deployment scenario, an LTE provider can configure a bandwidth of 1.4 MHz to 20 MHz in a single LTE CC, and a normal LTE UE supports transmission / reception capabilities of 20 MHz bandwidth for a single LTE CC.

[0102] However, NR is designed to support UEs with different transmit / receive bandwidth capabilities on a single wideband NR CC. Therefore, one or more bandwidth parts (BWPs) need to be configured, including Fig. 9 The sub-divided bandwidth for NR CCs is shown, thereby supporting flexible and wider bandwidth operation through configuration and activation of different bandwidth portions for corresponding UEs.

[0103] In particular, one or more bandwidth parts may be configured by a single serving cell configured for a UE in NR, and the UE is defined to activate one downlink (DL) bandwidth part and one uplink (UL) bandwidth part to use these for uplink / downlink data transmission / reception in the corresponding serving cell. In addition, in the case where multiple serving cells are configured for the UE (that is, a UE to which CA is applied), the UE is also defined to activate one downlink bandwidth part and / or one uplink bandwidth part in each serving cell, thereby using these for uplink / downlink data transmission / reception by utilizing the radio resources of the corresponding serving cell.

[0104] In particular, an initial bandwidth part for an initial access procedure may be defined for the UE in a serving cell; one or more UE-specific bandwidth parts may be configured for each UE via dedicated RRC signaling, and a default bandwidth part for fallback operation may be defined for each UE.

[0105] It is possible to define the simultaneous activation and use of multiple downlink and / or uplink bandwidth parts, depending on the capabilities of the UE and the configuration of the bandwidth parts in the serving cell. However, NR rel-15 defines that only one downlink (DL) bandwidth part and one uplink (UL) bandwidth part are activated and used at a time.

[0106] Hereinafter, a method for performing data transmission and reception in a wireless network will be described in detail with reference to relevant drawings.

[0107] Fig.10 is a flow chart illustrating a method for controlling transmission of an uplink data channel by a user equipment (UE) according to an embodiment.

[0108] refer to Fig.10 , the UE may receive configuration information regarding periodic transmission of an uplink data channel from a base station (S1010).

[0109] According to an embodiment, the UE may be a UE supporting XR services (extended reality (XR) UE). Extended reality (XR) refers to a group of immersive technologies including virtual reality (VR), augmented reality (AR), and mixed reality (MR). The UE is not limited to a specific device as long as it can provide XR services in a wireless environment.

[0110] Configuration information about the periodic transmission of the uplink data channel PUSCH can be received via higher layer signaling. In the following, an embodiment will be described based on a type 1 configuration grant (CG) in uplink scheduling. However, it is not limited to this. Unless it contradicts the technical spirit of the present disclosure, the embodiment can be applied to type 2CG in substantially the same manner.

[0111] According to an embodiment, the configuration information is information about parameters for configuring the periodic transmission of the uplink data channel. The configuration information may include time / frequency resources and periods, MCS configuration values ​​or similar information. The configuration information may be received via RRC signaling. In addition, the configuration information may include information about the number of times the uplink data channel is transmitted within a predetermined time interval. Here, the predetermined time interval may refer to the time interval for the transmission of the uplink data channel configured by the configuration information.

[0112] According to an embodiment, multiple uplink data channels transmitted in a time interval configured as a CG can be configured to have the same start and length indicator value (SLIV) in consecutive time slots. In other words, each uplink data channel can be configured to have the same starting symbol position and number of symbols in the time slot.

[0113] In addition, according to an embodiment, the number of times the uplink data channel is transmitted within a predetermined time interval may refer to the transmission opportunity of the uplink data channel. In this case, the UE may use uplink control information (UCI) to report to the base station the radio resources that are not actually used for the transmission of the uplink data channel. Here, the uplink control information for reporting unused transmission permissions (okay) may need to be newly defined. Alternatively, information about unused transmission permissions may be included in a new field in the existing CG-UCI, or may be included by changing the use of existing fields.

[0114] According to an embodiment, the CG configuration for periodic transmission of the uplink data channel can be dynamically changed by RRC signaling. To this end, in the configuration information, at least one of the parameters for periodic transmission of the uplink data channel can be configured as a complex number. In other words, at least one of the parameters (such as configured time resources and frequency resources, MCS index, antenna port, frequency hopping configuration or time offset) can be defined as multiple values. Alternatively, at least one of the parameters can be defined in the form of a predetermined range, or in the form of a range and a representative value.

[0115] In this case, as configured in the configuration information by RRC signaling, the UE can transmit the uplink data channel in the form of applying the parameters corresponding to each radio resource. For example, it is assumed that the MCS index is defined as a plurality of values ​​in the configuration information. According to the configuration information, the UE can transmit the uplink data channel in the first radio resource as the first MCS index. Thereafter, the UE can transmit the uplink data channel by applying the second MCS index configured to correspond to the second radio resource in the second radio resource.

[0116] In this case, according to an example, a parameter indicating whether to use downlink control information to change the configuration for the periodic transmission of the uplink data channel can be further defined. When the corresponding parameter is included in the configuration information, the UE can change the value currently applied to the parameter defined with multiple values ​​to the value indicated by the downlink control information. In this case, according to an example, the downlink control information can be received through a separate search space. Alternatively, the downlink control information can be received through an additional DCI format, which can be scrambled using a CS-RNTI or a newly defined RNTI.

[0117] For example, it is assumed that the MCS index is defined as a plurality of values ​​in the configuration information. In this case, the UE can transmit an uplink data channel by applying a first MCS index. Thereafter, when the UE receives downlink control information indicating a change to a second MCS index, the UE can transmit an uplink data channel by applying the second MCS index. The MCS index has been illustrated above, but at least one other parameter can also be naturally applied.

[0118] According to an embodiment, the configuration information may include multiple configured grants (CGs) for periodic transmission of an uplink data channel. In other words, each of the multiple CGs may be configured to have different parameter values ​​for periodic transmission of an uplink data channel. Therefore, the multiple CGs may be configured to have different parameter values, such as set time resources and frequency resources, MCS indexes, antenna ports, hopping configurations, or time offsets. The UE may transmit an uplink data channel by changing the configuration according to one of the multiple CGs activated by the downlink control information.

[0119] In this case, any one of the multiple CGs (configured and authorized) can be activated by the downlink control information. According to an embodiment, for activation, a list of multiple defined CGs can be arranged in ID order. Therefore, the list of CGs can be represented in the form of a bitmap in ID order, and can be indicated as the value of a predetermined field in the downlink control information. Therefore, the configuration of each CG can be activated and / or deactivated. Alternatively, their number is the same as the number of defined CGs, the CGs can be represented in the form of integers, and the CGs can be activated / deactivated in digital form. In this case, according to an embodiment, the downlink control information can be received through a separate search space. Alternatively, the downlink control information can be received through an additional DCI format, which can be scrambled with a CS-RNTI or a newly defined RNTI.

[0120] Return to reference Fig.10 , the UE can transmit an uplink data channel to the base station based on the configuration information (S1020).

[0121] As described above, according to the configuration information configured through the RRC signaling, the UE can transmit the uplink data channel by applying the parameters corresponding to each radio resource.

[0122] Alternatively, the UE may transmit an uplink data channel by changing the configuration according to one CG among multiple CGs activated by downlink control information.

[0123] According to the embodiments described above, resource allocation and scheduling may be efficiently performed by configuring separate configuration information for periodic data transmission / reception of UEs supporting an extended reality service.

[0124] Fig.11 1 is a flow chart illustrating a method 1100 for controlling reception of an uplink data channel by a base station according to an embodiment. Fig.10 The description of the combined operation may be omitted to avoid redundant description. The omitted content may be applied to the transmission UE in substantially the same manner as long as it does not contradict the technical spirit of the present disclosure.

[0125] refer to Fig.11 , the base station may transmit configuration information for positioning a reference signal to the UE (S1100).

[0126] The base station may transmit configuration information for periodic transmission of the uplink data channel PUSCH through higher layer signaling.

[0127] According to an embodiment, the configuration information is information about parameters for configuring the periodic transmission of the uplink data channel. The configuration information may include time / frequency resources and periods, MCS configuration values ​​or similar information. The configuration information may be received via RRC signaling. In this case, the configuration information may include information about the number of times the uplink data channel is transmitted within a predetermined time interval. Here, the predetermined time interval may refer to the time interval for the transmission of the uplink data channel configured by the configuration information.

[0128] According to an embodiment, the CG configuration for periodic transmission of the uplink data channel can be dynamically changed through RRC signaling. To this end, the base station can configure at least one of the multiple parameters for periodic transmission of the uplink data channel included in the configuration information with multiple values. In other words, at least one of the parameters (such as configured time resources and frequency resources, MCS index, antenna port, hopping configuration or time offset) can be defined using multiple values. Alternatively, at least one parameter can be defined in the form of a predetermined range, or defined as a range and a representative value.

[0129] In this case, as configured in the configuration information by RRC signaling, the base station can receive an uplink data channel from the UE in the form of applying parameters corresponding to each radio resource. For example, it is assumed that the MCS index is defined using multiple values ​​in the configuration information. According to the configuration information, the base station can receive an uplink data channel from the first radio resource to the first MCS index. Thereafter, the base station can receive an uplink data channel by applying a second MCS index configured to correspond to the second radio resource.

[0130] In this case, according to an embodiment, a parameter indicating whether to use downlink control information to change the configuration of the periodic transmission of the uplink data channel may be further defined. When the corresponding parameter is additionally included in the configuration information, the base station may change the value currently applied to the parameter defined with multiple values ​​to another value indicated by the downlink control information. In this case, according to an embodiment, the downlink control information may be received through a separate search space. Alternatively, the downlink control information may be received through an additional DCI format, which may be scrambled using a CS-RNTI or a newly defined RNTI.

[0131] For example, it is assumed that the MCS index is defined in the configuration information using multiple values. In this case, the base station can receive the uplink data channel by applying the first MCS index. Thereafter, when the base station transmits downlink control information indicating a change of the second MCS index, it can receive the uplink data channel by applying the second MCS index. The MCS index has been illustrated above, but it can also be naturally applied to at least one other parameter.

[0132] According to an embodiment, the configuration information may include multiple configured grants (CGs) for periodic transmission of an uplink data channel. In other words, each of the multiple CGs may be configured to have different parameter values ​​for periodic transmission of an uplink data channel. Therefore, the multiple CGs may be configured to have different parameter values, such as set time resources and frequency resources, MCS indexes, antenna ports, hopping configurations, or time offsets. The base station may receive an uplink data channel by changing the configuration according to one of the multiple CGs activated by the downlink control information.

[0133] In this case, any one of the multiple CGs (configured and authorized) can be activated by the downlink control information. According to an embodiment, for activation, a list of multiple defined CGs can be arranged in ID order. Therefore, the list of CGs can be represented in the form of a bitmap in ID order and can be indicated as the value of a predetermined field in the downlink control information. Therefore, the configuration of each CG can be activated and / or deactivated. Alternatively, their number is the same as the number of defined CGs, and the CGs can be represented in the form of integers. The CGs can be activated / deactivated in digital form. In this case, according to an embodiment, the downlink control information can be received through a separate search space. Alternatively, the downlink control information can be received through an additional DCI format, which can be scrambled with a CS-RNTI or a newly defined RNTI.

[0134] Return to reference Fig.11 , the base station can receive an uplink data channel from the UE based on the configuration information (S1120).

[0135] As described above, the base station may receive the uplink data channel in the form of applying parameters corresponding to each radio resource as configured in the configuration information through RRC signaling.

[0136] Alternatively, the base station can receive an uplink data channel by changing the configuration according to a CG activated by downlink control information among multiple CGs.

[0137] Therefore, resource allocation and scheduling can be performed more efficiently by configuring separate configuration information for periodic data transmission / reception of UEs supporting extended reality services.

[0138] Hereinafter, more embodiments of a method for performing data transmission / reception in a wireless network will be described in detail with reference to relevant drawings.

[0139] In NR, semi-persistent scheduling (SPS) is used for downlink and configured grant (CG) is used for uplink to schedule periodic traffic. In particular, in the case of downlink, the period is configured through a radio resource control (RRC) message (called SPS-Config), and then the activation / deactivation instructions and resource configuration are performed through downlink control information (DCI) scrambled with the configured scheduling RNTI (CS-RNTI). In the case of uplink, it is divided into type 1 and type 2. For type 1, all time / frequency resources, period, MCS configuration values, etc. are configured and transmitted through RRC. For type 2, based on the period configured through RRC, the actual transmission is indicated by time / frequency resources and MCS configuration values ​​through DCI scrambled with CS-RNTI. In this case, the configuration is performed using an RRC message called configuredgrantconfig. When a message called rrc-ConfiguredUplinkGrant (including resource and MCS value indication) is defined in the corresponding message, it is configured as type 1, and when it is not defined, it is set to type 2.

[0140] The following projects are under consideration or planned to enhance the standard for XR UEs.

[0141] Objectives of XR-awareness in RAN (RAN2):

[0142] - Study and identify XR traffic (both UL and DL) characteristics, QoS metrics, and application layer attributes that benefit gNB perception.

[0143] - Study how the above information can assist in XR specific traffic processing.

[0144] Regarding XR specific power saving targets (RAN1, RAN2):

[0145] - Research XR specific power saving techniques to adapt to XR service characteristics (periodicity, multi-stream, jitter, latency, reliability, etc.).

[0146] ℃-DRX enhanced.

[0147] °PDCCH monitoring enhancements.

[0148] Regarding XR-specific capacity improvement targets (RAN1, RAN2):

[0149] -Study mechanisms to provide more efficient resource allocation and scheduling based on XR service characteristics (periodicity, multi-stream, jitter, latency, reliability, etc.).

[0150] °SPS and CG enhancement.

[0151] ° Dynamic scheduling / authorization enhancements.

[0152] Among the items described above, power saving and capacitance enhancement are being pursued in XR. To this end, enhancements to transmission channels are being promoted, particularly SPS for downlink periodic transmission and CG for uplink periodic transmission.

[0153] Typical periodic transmission is intended to reduce UE overhead by virtue of the configuration period and other set values ​​through RRC. This is very advantageous in reducing UE power consumption by reducing reception complexity, but it may not be suitable for systems that require low latency. For example, when the period of SPS is short, the delay characteristics of the UE may be improved, but the resource management complexity may increase. Conversely, when the period is longer, in the case of XR, the frequency of additional resource allocation for fast packets is higher, which may result in increased overhead. Since the required latency is estimated to be between 10ms and 20ms, and the required packet interval may vary from time to time depending on the service, it is not possible to perform a configuration suitable for traffic characteristics only through RRC configuration.

[0154] The present disclosure provides a method for configuring periodic transmission in an NR transmission / reception environment. Specifically, it provides a method for dynamically changing the configuration in a downlink and a method for dynamically changing the configuration in an uplink.

[0155] Hereinafter, (1) an SPS transmission method supporting dynamic configuration changes and (2) a CG transmission method supporting dynamic configuration changes will be described.

[0156] (1) SPS transmission method supporting dynamic configuration changes

[0157] According to an embodiment, the method can dynamically change the setting value in the configuration for SPS as downlink periodic transmission. The method can be mainly divided into an RRC pre-configuration method and a configuration change instruction method in DCI.

[0158] ①RRC configuration method for SPS dynamic configuration change

[0159] The method configures RRC to dynamically change the SPS configuration. To this end, the period, HARQ-related parameters or repetition transmission parameters can be defined as multiple values, can be defined in the form of a range, or can be defined in the form of a range and a representative value. In addition, the RRC parameters indicating whether the configuration is changed by DCI can be further defined.

[0160] ②SPS configuration change instruction method in DCI

[0161] The method uses DCI to change the current SPS configuration. The method can be mainly divided into an activation / deactivation method, a cycle change method, a HARQ change method, and a repeated transmission configuration change method.

[0162] First, as an activation / deactivation method, a list of multiple SPSs can be arranged in ID order or a similar order, and then represented in bitmap form based on this, so that each SPS configuration can be activated / deactivated. Alternatively, the number of defined SPSs can be represented in integer form, and the SPS configuration can be activated / deactivated in digital form. For example, when eight SPSs are configured, the kth (or k-1th) SPS from 0 to 8 can be activated, and the k+1th (or kth) SPS can be deactivated, and vice versa. Alternatively, only the configuration of the kth SPS can be changed by an integer k from 1 to 8 and a bit.

[0163] For the period, the index of the configuration group previously configured by RRC can be indicated, or it can be indicated in the form of the previous period value or the next period value. The configurable period can be selected as one of 10ms, 20ms, 40ms, 64ms, 80ms, 128ms, 160ms, 320ms or 640ms, unless reconfigured otherwise (Rel.16). For example, when RRC configures 80ms as a period, it can be configured as 64 / 128 with 1 bit, or as 40 / 64 / 128 / 160 with 2 bits. Alternatively, in additional cases, it can be configured as half / twice with 1 bit, or as 1 / 3, 1 / 2, 2 times or 3 times with 2 bits. The configuration can be performed relative to the RRC pre-configured period, or it can also be performed relative to the last changed configuration period. In this case, when multiple SPSs are configured, the SPS whose configuration will be changed can be passed as an index.

[0164] For HARQ, the ID may be changed in the same manner as the period, or whether feedback transmission is performed may be determined.

[0165] Even in the case of repeated transmission, the transmission value can be changed in the same way as the period.

[0166] An additional DCI format may be defined to indicate a change in SPS configuration. In this case, the DCI may be sent through a separate search space and may be scrambled with a CS-RNTI or a newly defined RNTI.

[0167] (2) CG transmission method supporting dynamic configuration changes

[0168] The method can dynamically change the set value in the configuration of the CG used for uplink periodic transmission. The method can be mainly divided into an RRC pre-configuration method and a configuration change instruction method in a DCI. Each method can include type 1 to perform additional configuration for radio resources as an additional method.

[0169] ①RRC configuration method for CG dynamic configuration change

[0170] The method configures RRC to dynamically change the CG configuration. To this end, the periodic or repeated transmission parameters defined in ConfiguredGrantConfig can be defined using multiple values, can be defined in the form of a range, or can be defined in the form of a range and a representative value. Specifically, for type 1, parameters such as set time and frequency resources, MCS index, antenna port, frequency hopping configuration, or time offset can be defined using multiple values, or can be defined in the form of a range, or can be defined in the form of a range and a representative value. In addition, RRC parameters indicating whether the configuration is changed through DCI can be further defined.

[0171] ②CG configuration change instruction method in DCI

[0172] The method uses DCI to change the current SPS configuration. First, similar to SPS, the activation / deactivation of each of multiple configured CGs can be indicated. In addition, the periodic transmission configuration or the repeated transmission configuration can be changed.

[0173] First, as an activation / deactivation method, a list of multiple defined SPSs can be arranged in ID order and then represented in bitmap form based on this so that each CG configuration can be activated / deactivated. Alternatively, as many CGs as the number of defined CGs can be represented in the form of integers and activated / deactivated in digital form.

[0174] For periodic or repeated transmission, similar to the SPS described above, the index of the configuration group previously configured by RRC can be indicated, or it can be indicated in the form of a previous cycle value or a subsequent cycle value. The configuration can be performed relative to the RRC preset value, or it can also be performed relative to the last changed setting value. In the case of a cycle, only the change in the CP setting value can be transmitted. In this case, when there is no corresponding value such as sym5120x14, the cycle can be changed to the closest value or a specific value, such as sym2560x12, due to the corresponding indication.

[0175] In addition, the frequency hopping mode can be changed, and specifically, whether to perform frequency hopping can be changed by 1 bit. In the configuration described above, when multiple CGs are configured, the CG whose configuration is to be changed can be passed as an index.

[0176] Additional DCI formats may be defined to indicate changes to this configuration. DCI may be sent through a separate search space and may be scrambled with a CS-RNTI or a newly defined RNTI.

[0177] In the case of type 1, in addition to or separately from the previously described configuration, the MCS and time / frequency definition may also be changed. To this end, a PDSCH scrambled with a CS-RNTI as in type 2 may be transmitted in a preconfigured space to change the configuration of type 1 in order to transmit the corresponding information. Alternatively, it may be sent through a separate search space and may be changed by an additional DCI format that may be scrambled with a CS-RNTI or a newly defined RNTI. The DCI may be selected from a preconfigured candidate space for time / frequency resources. Alternatively, in the case of time resources, the DCI may indicate the use of n / k space in a frequency manner in a space configured by RRC in the case of frequency resources, and a new value of time domain resource allocation (TDRA) in the case of time resources. For example, it may be configured to be similar to {1, 1 / 2, 1 / 3, 1 / 4, 1 / 5, 2 / 3, 3 / 4, 4 / 5} through three bits, so that the frequency domain may be changed based on the region indicated in the existing RRC. In this case, it may additionally indicate changing the start PRB, changing the end PRB, or changing which one of the two to use for the resource configuration of the corresponding ratio.

[0178] In addition, the MCS setting value can be changed, for which it can be selected from preconfigured candidate values, or an instruction can be issued to move it by a specific value in the uplink / downlink direction. In this case, the corresponding specific value can be specified in the standard or otherwise indicated by RRC.

[0179] The method of the present disclosure can be applied independently or in any type of combination.In addition, among the terms used herein, novel terms are arbitrarily selected for ease of understanding, and the invention of the present disclosure is applicable even when other terms having the same meaning are used.

[0180] Through the method provided in the present disclosure, resource-efficient periodic uplink / downlink transmission matching the traffic characteristics of the XR UE can be performed.

[0181] Therefore, resource allocation and scheduling can be performed more efficiently by configuring separate configuration information for periodic data transmission / reception of UEs supporting extended reality services.

[0182] Hereinafter, the above combination will be described with reference to the accompanying drawings. Figures 1 to 11 Configurations of UE and base stations of all or some embodiments described. The above description may be omitted to avoid redundancy, and the omitted content may be applied to the following description in substantially the same manner as long as it does not contradict the technical spirit of the present disclosure.

[0183] Fig.12 is a block diagram illustrating a UE 1200 according to an embodiment.

[0184] refer to Fig.12 , the UE 1200 according to the embodiment includes a transmitter 1220, a receiver 1230, and a controller 1210 that controls operations of the transmitter and the receiver.

[0185] The controller 1210 may receive configuration information on periodic transmission of an uplink data channel from a base station. The configuration information on periodic transmission of an uplink data channel PUSCH may be received through higher layer signaling.

[0186] According to an embodiment, the configuration information is information about parameters for configuring the periodic transmission of the uplink data channel. The configuration information may include time / frequency resources and period, MCS configuration value or similar information as parameters. The configuration information may be received via RRC signaling. In this case, the configuration information may include information about the number of times the uplink data channel is transmitted within a predetermined time interval. Here, the predetermined time interval may refer to the time interval for the transmission of the uplink data channel configured by the configuration information.

[0187] According to an embodiment, the CG configuration for periodic transmission of the uplink data channel can be dynamically changed by RRC signaling. To this end, in the configuration information, at least one of the parameters for periodic transmission of the uplink data channel can be configured as a complex number. In other words, at least one of the parameters (such as configured time resources and frequency resources, MCS index, antenna port, frequency hopping configuration or time offset) can be defined as multiple values. Alternatively, at least one of the parameters can be defined in the form of a predetermined range, or in the form of a range and a representative value.

[0188] In this case, as configured in the configuration information by RRC signaling, the controller 1210 may transmit an uplink data channel in the form of applying a parameter corresponding to each radio resource. For example, assuming that the MCS index is defined as a plurality of values ​​in the configuration information. According to the configuration information, the controller 1210 may transmit an uplink data channel in a first radio resource as a first MCS index. Thereafter, the controller 1210 may transmit an uplink data channel by applying a second MCS index configured to correspond to a second radio resource in a second radio resource.

[0189] In this case, according to an example, a parameter indicating whether to use downlink control information to change the configuration of the periodic transmission of the uplink data channel can be further defined. When the corresponding parameter is included in the configuration information, the controller 1210 can change the value currently applied to the parameter defined with multiple values ​​to the value indicated by the downlink control information. In this case, according to an example, the downlink control information can be received through a separate search space. Alternatively, the downlink control information can be received through an additional DCI format, which can be scrambled using a CS-RNTI or a newly defined RNTI.

[0190] For example, it is assumed that the MCS index is defined as a plurality of values ​​in the configuration information. In this case, the controller 1210 can transmit the uplink data channel by applying the first MCS index. Thereafter, when receiving downlink control information indicating a change to the second MCS index, the controller 1210 can transmit the uplink data channel by applying the second MCS index. The MCS index has been illustrated above, but at least one other parameter can also be naturally applied.

[0191] According to an embodiment, the configuration information may include multiple configured grants (CGs) for periodic transmission of an uplink data channel. In other words, each of the multiple CGs may be configured to have different parameter values ​​for periodic transmission of an uplink data channel. Therefore, the multiple CGs may be configured to have different parameter values, such as set time resources and frequency resources, MCS indexes, antenna ports, hopping configurations, or time offsets. The controller 1210 may transmit an uplink data channel by changing the configuration according to one of the multiple CGs activated by the downlink control information.

[0192] In this case, any one of the multiple CGs (configured and authorized) can be activated by the downlink control information. According to an embodiment, for activation, a list of multiple defined CGs can be arranged in ID order. Therefore, the list of CGs can be represented in the form of a bitmap in ID order, and can be indicated as the value of a predetermined field in the downlink control information. Therefore, the configuration of each CG can be activated and / or deactivated. Alternatively, their number is the same as the number of defined CGs, the CGs can be represented in the form of integers, and the CGs can be activated / deactivated in digital form. In this case, according to an embodiment, the downlink control information can be received through a separate search space. Alternatively, the downlink control information can be received through an additional DCI format, which can be scrambled with a CS-RNTI or a newly defined RNTI.

[0193] The controller 1210 may transmit an uplink data channel to the base station based on the configuration information.As described above, the controller 1210 may transmit an uplink data channel in the form of applying parameters corresponding to each radio resource as configured in the configuration information through RRC signaling.

[0194] Alternatively, the controller 1210 may transmit an uplink data channel by changing the configuration according to one CG among a plurality of CGs activated by downlink control information.

[0195] Therefore, resource allocation and scheduling can be efficiently performed by configuring separate configuration information for periodic data transmission / reception of UEs supporting the extended reality service.

[0196] Fig.13 is a block diagram showing a base station 1300 according to an embodiment.

[0197] refer to Fig.13 , a base station 1300 according to another embodiment includes a transmitter 1320, a receiver 1330, and a controller 1310 that controls operations of the transmitter and the receiver.

[0198] The controller 1310 may transmit configuration information for positioning a reference signal to the UE.

[0199] The controller 1310 may transmit configuration information for periodic transmission of the uplink data channel PUSCH through higher layer signaling.

[0200] According to an embodiment, the configuration information is information about parameters for configuring the periodic transmission of the uplink data channel. The configuration information may include time / frequency resources and period, MCS configuration value or similar information as parameters. The configuration information may be received via RRC signaling. In this case, the configuration information may include information about the number of times the uplink data channel is transmitted within a predetermined time interval. Here, the predetermined time interval may refer to the time interval for the transmission of the uplink data channel configured by the configuration information.

[0201] According to an embodiment, the CG configuration for periodic transmission of the uplink data channel can be dynamically changed by RRC signaling. To this end, the controller 1310 can configure at least one of the multiple parameters for periodic transmission of the uplink data channel included in the configuration information with multiple values. In other words, at least one of the parameters (such as configured time resources and frequency resources, MCS index, antenna port, hopping configuration or time offset) can be defined using multiple values. Alternatively, at least one parameter can be defined in the form of a predetermined range, or in the form of a range and a representative value.

[0202] In this case, as configured in the configuration information by RRC signaling, the controller 1310 can receive an uplink data channel from the UE in the form of applying a parameter corresponding to each radio resource. For example, it is assumed that the MCS index is defined using multiple values ​​in the configuration information. According to the configuration information, the controller 1310 can receive an uplink data channel from the first radio resource to the first MCS index. Thereafter, the controller 1310 can receive an uplink data channel by applying a second MCS index configured to correspond to the second radio resource.

[0203] In this case, according to an embodiment, a parameter indicating whether to use downlink control information to change the configuration of the periodic transmission of the uplink data channel can be further defined. When the corresponding parameter is additionally included in the configuration information, the controller 1310 can indicate that the value currently applied to the parameter defined with multiple values ​​is changed to another value indicated by the downlink control information. In this case, according to an embodiment, the downlink control information can be received through a separate search space. Alternatively, the downlink control information can be received through an additional DCI format, which can be scrambled using a CS-RNTI or a newly defined RNTI.

[0204] For example, it is assumed that the MCS index is defined in the configuration information using multiple values. In this case, the controller 1310 can receive the uplink data channel by applying the first MCS index. Thereafter, when transmitting downlink control information indicating the change of the second MCS index, the controller 1310 can receive the uplink data channel by applying the second MCS index. The MCS index has been illustrated above, but it can also be naturally applied to at least one other parameter.

[0205] According to an embodiment, the configuration information may include multiple configured grants (CGs) for periodic transmission of an uplink data channel. In other words, each of the multiple CGs may be configured to have different parameter values ​​for periodic transmission of an uplink data channel. Therefore, the multiple CGs may be configured to have different parameter values, such as set time resources and frequency resources, MCS indexes, antenna ports, hopping configurations, or time offsets. The controller 1310 may receive an uplink data channel by changing the configuration according to one of the multiple CGs activated by the downlink control information.

[0206] In this case, any one of the multiple CGs (configured and authorized) can be activated by the downlink control information. According to an embodiment, for activation, a list of multiple defined CGs can be arranged in ID order. Therefore, the list of CGs can be represented in the form of a bitmap in ID order and can be indicated as the value of a predetermined field in the downlink control information. Therefore, the configuration of each CG can be activated and / or deactivated. Alternatively, their number is the same as the number of defined CGs, and the CGs can be represented in the form of integers. The CGs can be activated / deactivated in digital form. In this case, according to an embodiment, the downlink control information can be received through a separate search space. Alternatively, the downlink control information can be received through an additional DCI format, which can be scrambled with a CS-RNTI or a newly defined RNTI.

[0207] The controller 1310 may receive an uplink data channel from the UE based on the configuration information. As described above, the controller 1310 may receive the uplink data channel in the form of applying parameters corresponding to each radio resource as configured in the configuration information through RRC signaling.

[0208] Alternatively, the controller 1310 may receive an uplink data channel by changing the configuration according to a CG activated by downlink control information among a plurality of CGs.

[0209] Therefore, resource allocation and scheduling can be performed more efficiently by configuring separate configuration information for periodic data transmission / reception of UEs supporting extended reality services.

[0210] The embodiments described above may be supported by standard documents disclosed in at least one of the radio access systems such as IEEE 802, 3GPP, and 3GPP2. That is, steps, configurations, and parts that have not been described in the present embodiments may be supported by the standard documents mentioned above for explaining the technical concepts of the present disclosure. In addition, all terms disclosed herein may be described by the standard documents set forth above.

[0211] The embodiments described above may be implemented by any of a variety of means. For example, the embodiments may be implemented as hardware, firmware, software, or a combination thereof.

[0212] When implemented by hardware, the method according to this embodiment can be implemented as at least one of an application specific integrated circuit (ASIC), a digital signal processor (DSP), a digital signal processing device (DSPD), a programmable logic device (PLD), a field programmable gate array (FPGA), a processor, a controller, a microcontroller or a microprocessor.

[0213] In the case of implementation by firmware or software, the method according to the present embodiment can be implemented in the form of a device, process or function for performing the functions or operations described above. The software code can be stored in a memory unit and can be driven by a processor. The memory unit can be arranged inside or outside the processor and can exchange data with the processor through various well-known devices.

[0214] In addition, the terms "system", "processor", "controller", "component", "module", "interface", "model", and "unit" and the like may generally refer to computer-related physical hardware, a combination of hardware and software, software, or running software. For example, the components described above may be, but are not limited to, processes driven by a processor, processors, controllers, control processors, entities, execution threads, programs, and / or computers. For example, an application running in a controller or processor and a controller or processor may be a component. One or more components may be set in a process and / or execution thread, and these components may be set in a single device (e.g., a system, a computing device, etc.), or may be distributed across two or more devices.

[0215] The above-mentioned embodiments of the present disclosure have been described for illustrative purposes only, and those skilled in the art will recognize that various modifications and changes may be made thereto without departing from the scope and spirit of the present disclosure. In addition, the embodiments of the present disclosure are not intended to be limiting, but are intended to illustrate the technical ideas of the present disclosure, and therefore the scope of the technical ideas of the present disclosure is not limited by these embodiments. The scope of the present disclosure should be interpreted on the basis of the attached claims so that all technical ideas included in the scope equivalent to the claims belong to the present disclosure.

[0216] CROSS-REFERENCE TO RELATED APPLICATIONS

[0217] This application claims priority to Korean Patent Application No. 10-2022-0057107 filed on May 10, 2022 and Korean Patent Application No. 10-2023-0060059 filed on May 9, 2023, the disclosures of which are incorporated herein by reference in their entirety.

Claims

1. A method for transmitting data by a user equipment (UE), the method comprising: receiving configuration information about periodic transmission of an uplink data channel from a base station; as well as transmitting the uplink data channel to the base station based on the configuration information, The UE supports extended reality (XR) services.

2. The method according to claim 1, wherein: The configuration information is received by higher layer signaling and includes information on the number of times the uplink data channel is transmitted within a predetermined time interval.

3. The method according to claim 2, wherein: In the configuration information, at least one parameter among parameters for periodic transmission of the uplink data channel is configured as a plural number.

4. The method according to claim 1, wherein: The configuration information includes a plurality of configured grants (CGs) for periodic transmission of the uplink data channel.

5. The method according to claim 4, wherein: Among the plurality of configured grants, any one configured grant among the plurality of configured grants is activated by downlink control information.

6. A method for receiving data by a base station, the method comprising: Transmitting configuration information about periodic transmission of an uplink data channel to a UE; as well as receiving the uplink data channel from the UE based on the configuration information, The UE supports extended reality (XR) services.

7. The method according to claim 6, wherein: The configuration information is transmitted by higher layer signaling, and includes information on the number of times the uplink data channel is transmitted within a predetermined time interval.

8. The method according to claim 7, wherein: In the configuration information, at least one parameter among parameters for periodic transmission of the uplink data channel is configured as a plural number.

9. The method according to claim 6, wherein: The configuration information includes a plurality of configured grants (CGs) for periodic transmission of the uplink data channel.

10. The method according to claim 9, wherein: Among the plurality of configured grants, any one configured grant among the plurality of configured grants is activated by downlink control information.

11. A UE for transmitting data, comprising: Transmitter; Receiver; and a controller configured to control operations of the transmitter and the receiver, receive configuration information regarding periodic transmission of an uplink data channel, and transmit the uplink data channel based on the configuration information, The UE supports extended reality (XR) services.

12. The UE according to claim 11, wherein: The configuration information is received by higher layer signaling and includes information on the number of times the uplink data channel is transmitted within a predetermined time interval.

13. The UE according to claim 12, wherein: In the configuration information, at least one parameter among parameters for periodic transmission of the uplink data channel is configured as a plural number.

14. The UE according to claim 11, wherein: The configuration information includes a plurality of configured grants (CGs) for periodic transmission of the uplink data channel.

15. The UE according to claim 14, wherein: Among the plurality of configured grants, any one configured grant among the plurality of configured grants is activated by downlink control information.

Images