Method and apparatus for controlling paging operations

Abstract

The present embodiment relates to a method and apparatus for controlling a paging operation, and provides a method for a terminal to perform a paging operation, the method comprising the following steps: receiving a paging message including identification information of each terminal for identifying a target for performing a paging operation; and determining whether to apply the paging message based on the identification information.

Description

Technical Field

[0001] This embodiment proposes a method and device for controlling paging occasions 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 the "Study on New Radio Access Technology," a research project for 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 (RANWG1) has been discussing the frame structure, channel coding and modulation, waveform, multiple access method, etc. 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 representative use cases for NR. To meet the requirements of each scenario, NR needs to be designed with a flexible frame structure compared to LTE / LTE-Advanced.

[0004] Because the requirements for data rate, latency, reliability, coverage, etc. are different from each other, a method for efficiently multiplexing radio resource units based on different parameter sets (numerologies) (for example, subcarrier spacing, subframe, Transmission Time Interval (TTI)), etc., is needed as a method to effectively meet the requirements of each usage scenario through the frequency band constituting any NR system.

[0005] As part of this, a design for reducing power consumption and performing efficient paging operations in NR is required. Summary of the Invention

[0006] Technical issues

[0007] Embodiments of the present disclosure may provide a method and apparatus for controlling a paging operation, in which paging messages are transmitted separately to apply to different UEs sharing the same resources.

[0008] Technical Solutions

[0009] In one aspect, the present embodiment may provide a method for performing a paging operation by a UE, comprising receiving a paging message including per-UE identification information for identifying a target undergoing the paging operation; and determining whether to apply the paging message based on the identification information.

[0010] In another aspect, the present embodiment may provide a method for controlling a paging operation of a UE by a base station, including configuring a paging message including per-UE identification information for identifying a target undergoing a paging operation; and transmitting the paging message.

[0011] In another aspect, the present embodiment may provide a UE performing a paging operation, including a receiver receiving a paging message including per-UE identification information for identifying a target undergoing the paging operation and a controller determining whether to apply the paging message according to the identification information.

[0012] In another aspect, the present embodiment may provide a base station for controlling a paging operation of a UE, including a controller for configuring a paging message including per-UE identification information for identifying a target undergoing a paging operation and a transmitter for transmitting the paging message.

[0013] Beneficial effects

[0014] According to the present embodiment, a method and apparatus for controlling a paging operation may be provided, in which paging messages are transmitted separately to apply to different UEs sharing the same resources.

[0015] Furthermore, according to the present embodiment, power consumption caused by erroneously receiving a paging message delivered to a different UE can be saved. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 2 is a diagram schematically illustrating an NR wireless communication system according to an embodiment of the present disclosure.

[0017] Figure 2 2 is a view schematically illustrating a frame structure in an NR system according to an embodiment of the present disclosure.

[0018] Figure 3 is a view for explaining a resource grid supported by a radio access technology according to an embodiment of the present disclosure.

[0019] Figure 4 is a view for explaining a bandwidth portion supported by a radio access technology according to an embodiment of the present disclosure.

[0020] Figure 5 is a view illustrating an example of a synchronization signal block in a radio access technology according to an embodiment of the present disclosure.

[0021] 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.

[0022] Figure 7 It is a view used to explain CORESET.

[0023] Figure 8 is a diagram illustrating an example of symbol-level alignment between different subcarrier spacings (SCSs) according to an embodiment of the present disclosure.

[0024] Figure 9 FIG. 4 is a diagram schematically illustrating a portion of bandwidth to which an embodiment of the present disclosure is applicable.

[0025] Figure 10 is a view illustrating a process of performing a paging occasion by a UE according to an embodiment.

[0026] Figure 11 is a view illustrating a process of controlling a paging occasion of a UE by a base station according to an embodiment.

[0027] Figure 12 is a diagram illustrating a user equipment according to an embodiment; and

[0028] Figure 13 is a view showing a base station according to an embodiment. DETAILED DESCRIPTION

[0029] Hereinafter, some embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In the accompanying drawings, the same reference numerals are used to represent the same elements throughout the accompanying drawings, even if they are shown in different drawings. In addition, in the following description of the present disclosure, when a detailed description of the known functions and configurations incorporated herein may make the subject matter of the present disclosure quite unclear, it will be omitted. When using expressions such as "include", "have", "comprise", etc. as mentioned herein, any other parts may be added unless the expression "only" is used. When an element is expressed in the singular, the element may cover the plural form unless the particularity of the element is explicitly mentioned.

[0030] In addition, when describing the components of the present disclosure, terms such as first, second, A, B, (A), (B), etc. may be used herein. Each of these terms is not used to limit the nature, order or sequence of the corresponding components, but is only used to distinguish the corresponding component from other components.

[0031] When 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 that 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.

[0032] When describing the order of an operating method or a manufacturing method, for example, expressions using “after,” “subsequent to,” “next,” “before,” etc. may also include the case where the operations or processes are not performed continuously, unless “immediately” or “directly” is used in the expression.

[0033] Numerical values (e.g., levels, etc.) of components or information corresponding thereto mentioned herein may be construed as including error ranges caused by various factors (e.g., process factors, internal or external influences, noise, etc.) even if no explicit description thereof is provided.

[0034] The wireless communication system in this specification refers to a system that uses radio resources to provide various communication services (such as voice services and data services). The wireless communication system may include user equipment (UE), base stations, core networks, etc.

[0035] 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), non-orthogonal multiple access (NOMA), etc. In addition, the radio access technology can refer to various generations of communication technologies established by various communication organizations, such as 3GPP, 3GPP2, WiFi, Bluetooth, IEEE, 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 Rates 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), etc. IEEE 802.16m is an evolution of IEEE 802.16e, which provides backward compatibility with IEEE 802.16e-based systems. 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) that uses 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 already been launched or commercialized, and can also be applied to radio access technologies that are being developed or will be developed in the future.

[0036] 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, UE includes user equipment (UE) in WCDMA, LTE, NR, HSPA, IMT-2020 (5G or new air interface), etc., mobile stations in GSM, user terminals (UT), subscriber stations (SS), wireless devices, etc. In addition, UE can be a portable user device such as a smartphone, or it can be a vehicle, a device including a wireless communication module in a vehicle, and similar devices in a V2X communication system depending on its type of use. In the case of a machine type communication (MTC) system, UE can refer to an MTC terminal, an M2M terminal, or a URLLC terminal, which utilizes a communication module capable of performing machine type communication.

[0037] In this specification, a base station or cell refers to an end that communicates with a UE through a network and includes various coverage areas, such as a Node-B, an evolved Node-B (eNB), a gNode-B, a low-power node (LPN), a sector, a site, various types of antennas, a base transceiver system (BTS), an access point, a point (e.g., a transmission point, a reception point, or a transmission / reception point), a relay node, a macro cell, a macro cell, a micro cell, a pico cell, a femto cell, and the like. Furthermore, the term "cell" may be used to refer to a bandwidth part (BWP) in the frequency domain. For example, a serving cell may refer to the active BWP of a UE.

[0038] The various cells listed above are equipped with base stations that control one or more cells, and the base station can be interpreted in 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 device that is controlled by the same entity and provides a predetermined wireless area, or all devices that interact and cooperate with each other to configure the wireless area. For example, depending on the configuration method of the wireless area, the base station can be a point, a transmission / reception point, a transmission point, a reception point, etc. In the above description 2), the base station can be a wireless area in which a user equipment (UE) can be enabled to transmit data to and receive data from other UEs or adjacent base stations.

[0039] In this specification, a cell may refer to 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.

[0040] 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 can mean communication or a communication path from multiple transmission / reception points to a UE, and uplink can mean communication or a communication path from a UE to multiple transmission / reception points. In the downlink, a transmitter can be part of multiple transmission / reception points, and a receiver can be part of a UE. In addition, in the uplink, a transmitter can be part of a UE, and a receiver can be part of multiple transmission / reception points.

[0041] 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, PDSCH, etc. may be expressed as "PUCCH, PUSCH, PDCCH, PDSCH, etc. are transmitted and received."

[0042] For clarity, the following description will focus on 3GPP LTE / LTE-A / NR (New Radio) communication systems, but the technical features of the present disclosure are not limited to the corresponding communication systems.

[0043] After studying 4G (4th-generation) communication technologies, 3GPP has been developing 5G (fifth-generation) communication technologies to meet the requirements of ITU-R's next-generation radio access technologies. Specifically, 3GPP is developing LTE-A pro as a 5G communication technology by improving LTE-Advanced technologies to comply with the requirements of ITU-R and the new NR communication technologies that are completely different from 4G communication technologies. LTE-A pro and NR both refer to 5G communication technologies. Hereinafter, unless a specific communication technology is specified, 5G communication technologies will be described based on NR.

[0044] Considering satellites, automobiles, new vertical industries, etc. in typical 4G LTE scenarios, various operation scenarios have been defined in NR to support enhanced mobile broadband (eMBB) scenarios in terms of services, where UEs are distributed over a wide area with a high UE density, thus requiring low data rates and asynchronous connections for massive machine-type communication (mMTC) scenarios, and ultra-reliable low-latency (URLLC) scenarios that require high responsiveness and reliability and support high-speed mobility. [[ID=,7]]

[0045] To meet such scenarios, NR introduces a wireless communication system that employs new waveform and frame structure technologies, low-latency technologies, ultra-high frequency band (mmWave) support technologies, and forward-compatible supply technologies. In particular, the NR system has various technical variations in terms of flexibility to provide forward compatibility. The main technical features of NR will be described below with reference to the accompanying drawings.

[0046] <Overview of the NR System>

[0047] Figure 1 is a view schematically showing an NR system to which the present embodiment is applicable.

[0048] Refer to 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 endpoints of the user plane (SDAP / PDCP / RLC / MAC / PHY) and the control plane (RRC) of the user equipment (UE). The gNBs or the gNBs and ng-eNBs are connected to each other through the Xn interface. The gNBs and ng-eNBs are connected to the 5GC through 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 frequency bands below 6 GHz (frequency range 1, FR1) and frequency bands equal to or greater than 6 GHz (frequency range 2, FR2).

[0049] A gNB refers to a base station that provides the protocol endpoints of the NR user plane and control plane to the UE. An ng-eNB refers to a base station that provides the protocol endpoints of the E-UTRA user plane and control plane to the UE. The base stations described in this specification should be understood to include gNBs and ng-eNBs. However, the base station can also be used to refer to the gNB or ng-eNB separately when necessary.

[0050] <NR Waveform, Parameter Set, and Frame Structure>

[0051] NR uses the CP-OFDM waveform with a cyclic prefix for downlink transmission and uses CP-OFDM or DFT-s-OFDM for uplink transmission. The OFDM technology is easy to combine with multiple-input multiple-output (MIMO) schemes and allows for the use of a low-complexity receiver with high frequency efficiency.

[0052] Since the above three scenarios have different requirements for data rate, latency rate, coverage, etc. in NR, it is necessary to effectively meet the requirements for each scenario on the frequency bands constituting the NR system. For this purpose, a technology for effectively multiplexing radio resources based on multiple different parameter sets has been proposed.

[0053] Specifically, 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.

[0054] [Table 1]

[0055] 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

[0056] As shown in Table 1 above, NR can have five types of parameter sets according to the subcarrier spacing. This is different from LTE, one of the 4G communication technologies, in which the subcarrier spacing is fixed to 15kHz. Specifically, in NR, the subcarrier spacing for data transmission is 15, 30, 60 or 120kHz, and the subcarrier spacing for synchronization signal transmission is 15, 30, 120 or 240kHz. In addition, the extended CP is only applicable to the subcarrier spacing of 60kHz. A frame consisting of 10 subframes is defined in the frame structure in NR, each subframe has the same length of 1ms and a length of 10ms. One frame can be divided into half frames of 5ms, and each half frame includes 5 subframes. When the subcarrier spacing is 15kHz, one subframe includes one time slot, and each time slot includes 14 OFDM symbols; Figure 2 This is a diagram for explaining a frame structure in an NR system to which this embodiment is applicable. Figure 2 , a time slot includes 14 OFDM symbols, which are fixed in the case of normal CP, but the time slot length in the time domain can vary depending on the subcarrier spacing. For example, in the case of a parameter set with a subcarrier spacing of 15kHz, the time slot is configured to have the same length of 1ms as the subframe. On the other hand, in the case of a parameter set with a subcarrier spacing of 30kHz, the time slot includes 14 OFDM symbols, but one subframe may include two time slots, each with a length of 0.5ms. That is, subframes and frames can be defined using a fixed time length, and the time slot can be defined as the number of symbols so that its time length varies depending on the subcarrier spacing.

[0057] NR defines the basic unit of scheduling as a timeslot and also introduces microslots (or subslots or non-slot-based scheduling) to reduce transmission delay in the radio part. If a wide subcarrier spacing is used, the length of a timeslot is shortened inversely proportional to it, thereby reducing transmission delay in the radio part. Microslots (or subslots) are designed to efficiently support URLLC scenarios and can be scheduled in 2, 4, or 7 symbol units.

[0058] Furthermore, unlike LTE, NR defines uplink and downlink resource allocation at the symbol level within a slot. To reduce HARQ latency, a slot structure has been defined that enables HARQ ACK / NACK to be transmitted directly within the transmission slot. This slot structure is called a "self-contained structure," which will be described below.

[0059] NR is designed to support a total of 256 slot formats, of which 62 slot formats are used in 3GPP Rel-15. In addition, NR supports a common frame structure that forms FDD or TDD frames through combinations of various time slots. For example, NR supports i) a time slot structure where all symbols of the time slot are configured for downlink, ii) a time slot structure where all symbols are configured for uplink, and iii) a time slot structure where downlink symbols and uplink symbols are mixed. In addition, NR supports data transmission scheduled to one or more time slots. Therefore, the base station can use a slot format indicator (SFI) to notify the UE whether the time slot is a downlink time slot, an uplink time slot, or a flexible time slot. The base station can notify the slot format by indicating the index of a table configured through UE-specific RRC signaling using the SFI. In addition, the base station can dynamically indicate the slot format through downlink control information (DCI), or can statically or quasi-statically indicate the slot format through RRC signaling.

[0060] <Physical Resources of NR>

[0061] Regarding the physical resources in NR, antenna ports, resource grids, resource elements, resource blocks, bandwidth parts, etc. are considered.

[0062] An antenna port is defined as a channel carrying a symbol on one antenna port being inferred from another channel carrying another symbol on the same antenna port. If the large-scale characteristics of the channel carrying the symbol on one antenna port can be inferred from another channel carrying a symbol on another antenna port, then these two antenna ports can have a quasi-co-location or quasi-co-site (QC / QCL) relationship. The large-scale attributes include at least one of delay spread, Doppler spread, frequency shift, average received power, and reception timing.

[0063] Figure 3 A resource grid supported by a radio access technology according to an embodiment of the present disclosure is shown.

[0064] Refer to 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 may depend on antenna ports, subcarrier spacing, and transmission direction.

[0065] 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 3As shown, the size of a resource block can vary according to the subcarrier spacing. In addition, "Point A", which serves as a common reference point for the resource block grid, common resource blocks, and virtual resource blocks, is defined in NR.

[0066] Figure 4 Fig. shows a bandwidth part supported by a radio access technology according to an embodiment of the present disclosure.

[0067] Unlike LTE where the carrier bandwidth is fixed at 20 MHz, the maximum carrier bandwidth is configured to be 50 MHz to 400 MHz according to the subcarrier spacing in NR. Therefore, it is not assumed that all UEs use the entire carrier bandwidth. Thus, as Figure 4 shown, a bandwidth part (BWP) can be specified within the carrier bandwidth in NR such that a UE can use the same bandwidth part. In addition, 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 send and receive data during a given time period.

[0068] In the case of paired spectrum, the uplink and downlink bandwidth parts 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 paired-configured to share the center frequency.

[0069] <Initial Access in NR>

[0070] In NR, a UE performs a cell search and a random access procedure to access a base station and communicate with it.

[0071] Cell search is a process in which a UE synchronizes with a cell of a corresponding base station using a Synchronization Signal Block (SSB) sent from the base station and obtains the physical layer cell ID and system information.

[0072] Figure 5 Fig. shows an example of a Synchronization Signal Block in a radio access technology according to an embodiment of the present disclosure.

[0073] Refer 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 Physical Broadcast Channels (PBCHs) that span three OFDM symbols and 240 subcarriers.

[0074] The UE monitors the SSB in the time domain and frequency domain, thereby receiving the SSB. <000,0207>

[0075] An SSB can be transmitted up to 64 times within 5 ms. Multiple SSBs are transmitted over different transmit beams within 5 ms, and the UE performs detection based on the specific beam used for transmission, assuming that an SSB is transmitted every 20 ms. As the frequency band increases, the number of beams that can be used for SSB transmission within 5 ms can increase. For example, up to 4 SSB beams can be transmitted in a frequency band of 3 GHz or lower, and up to 8 SSB beams can be transmitted in a frequency band of 3 to 6 GHz. In addition, up to 64 different beams can be used to transmit SSBs in a frequency band of 6 GHz or higher.

[0076] 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.

[0077] Unlike SS in a typical LTE system, SSB is not transmitted on the center frequency of the carrier bandwidth. That is, in the case of supporting wideband operation, SSB can also be sent on frequencies outside the center of the system band, and multiple SSBs can be sent in the frequency domain. Therefore, the UE monitors SSB using a synchronization raster, which is a candidate frequency position for monitoring SSB. The carrier raster and synchronization raster, which are the center frequency position information of the channel for initial connection, are newly defined in NR, and the synchronization raster can support the UE's fast SSB search because its frequency interval is configured to be wider than the frequency interval of the carrier raster.

[0078] The UE can obtain the MIB through 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 numerology information, information related to SIB1CORESET, search space information, parameter information related to PDCCH, etc.), offset information between common resource blocks and SSBs (the position of the absolute SSB in the carrier is sent via SIB1), etc. The SIB1 numerology 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 of the random access process.

[0079] The above-mentioned RMSI may refer to SIB1 (System Information Block 1), which is broadcast periodically (e.g., 160ms) in the cell. SIB1 includes information required for the UE to perform the initial random access process, 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 through PBCH. The UE uses the SI-RNTI in the CORESET to identify the scheduling information of SIB1. The UE obtains 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.

[0080] Figure 6 This is a diagram for explaining a random access procedure in a wireless access technology to which this embodiment is applicable.

[0081] Reference 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 via the PRACH. Specifically, the random access preamble is periodically transmitted to the base station via the PRACH, which includes continuous radio resources in repeated specific time slots. Generally, when the UE makes initial access to 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.

[0082] 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 one random access response may include random access response information of one or more UEs, the random access preamble identifier may be included to indicate the UE for which the included UL grant, temporary C-RNTI, and TAC are valid. The random access preamble identifier may be an identifier of the random access preamble received by the base station. The TAC may be included as information for the UE to adjust uplink synchronization. The random access response may be indicated by a random access identifier on the PDCCH, i.e., a random access radio network temporary identifier (RA-RNTI).

[0083] 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.

[0084] Finally, the UE receives a downlink message to resolve the contention.

[0085] <nrcoreset>

[0086] The downlink control channel in NR is transmitted in a CORESET (Control Resource Set) with a length of 1 to 3 symbols, and the downlink control channel transmits uplink / downlink scheduling information, SFI (Slot Format Index), TPC (Transmit Power Control) information, etc.

[0087] As mentioned above, to ensure system flexibility, NR introduces the concept of CORESET. A CORESET (Control Resource Set) refers to the time-frequency resources used for downlink control signals. The UE can use one or more search spaces within the CORESET time-frequency resources to decode control channel candidates. A CORESET-specific QCL (quasi-co-location) hypothesis is configured and used to provide information about the simulated beam direction, as well as delay spread, Doppler spread, Doppler shift, and average delay, which are characteristics of existing QCL assumptions.

[0088] Figure 7 A CORESET is shown.

[0089] Reference Figure 7 , a CORESET can exist in various forms within the carrier bandwidth in a single time slot, and a CORESET can include up to 3 OFDM symbols in the time domain. In addition, a CORESET is defined as a multiple of six resource blocks up to the carrier bandwidth in the frequency domain.

[0090] 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.

[0091] In this specification, frequencies, frames, subframes, resources, resource blocks, areas, frequency bands, subbands, control channels, data channels, synchronization signals, various reference signals, various signals, or various messages related to NR (New Radio) may be interpreted as meanings used currently or in the past, or as various meanings used in the future.

[0092] NR (New Radio)

[0093] Compared to LTE / LTE-Advanced, NR needs to be designed to not only provide improved data transmission rates but also meet the various QoS requirements for each detailed and specific use case. In particular, enhanced mobile broadband (eMBB), massive machine-type communications (mMTC), and ultra-reliable and low-latency communications (URLLC) are defined as representative use cases for NR. To meet the requirements of each use case, NR needs to be designed with a more flexible frame structure compared to LTE / LTE-Advanced.

[0094] Because each usage scenario has different requirements for data rate, latency, coverage, etc. Therefore, a method of efficiently multiplexing radio resource units that are different from each other based on digital (e.g., subcarrier spacing (SCS), subframe, transmission time interval (TTI), etc.) is needed as a solution to effectively meet the requirements according to the usage scenario on the frequency band provided to the NR system.

[0095] To this end, i) a method of multiplexing values with subcarrier spacing (SCS) values different from each other 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 time domain structure. In addition, as a reference parameter set for defining the duration of the corresponding subframe, a single subframe duration is defined as 14 OFDM symbols with a normal CP overhead based on a 15kHz subcarrier spacing (SCS), similar to LTE. Therefore, the subframe of NR has a duration of 1ms. Unlike LTE, because 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, regardless of the parameter set, the number of OFDM symbols constituting the time slot, value y, has been defined as y=14.

[0096] Therefore, one slot may consist of 14 symbols. Depending on the transmission direction of the corresponding slot, all symbols may be used for DL transmission or UL transmission, or symbols may be used in a configuration of DL part + slot + UL part.

[0097] In addition, mini-slots have been defined as consisting of fewer symbols than slots in a parameter set (or SCS), so a short time domain scheduling interval can be configured for UL / DL data transmission or reception based on mini-slots. In addition, a long time domain scheduling interval can be configured for UL / DL data transmission or reception through slot aggregation.

[0098] Specifically, when transmitting or receiving delay-critical data (e.g., URLLC), when scheduling is performed based on a 1 ms (14 symbols) time slot defined in a frame structure based on a parameter set with a small SCS value (e.g., 15 kHz), the delay requirement may be difficult to meet. To this end, a mini-time slot consisting of fewer OFDM symbols than the time slot can be defined, and thus scheduling of delay-critical data (e.g., URLLC) can be performed based on the mini-time slot.

[0099] As mentioned above, by multiplexing different SCS values in one NR carrier in a TDM and / or FDM manner to support this parameter set, it is also expected that data can be scheduled according to the latency requirements based on the slot (or mini-slot) length defined by the parameter set. Figure 8 As shown in FIG, when the SCS is 60kHz, the symbol length is reduced to about 1 / 4 of the SCS 15kHz. Therefore, when a slot consists of 14 OFDM symbols, the slot length based on 15kHz is 1ms, while the slot length based on 60kHz is reduced to about 0.25ms.

[0100] Therefore, since different SCSs or different TTI lengths are defined in NR, a technology has been developed to meet the requirements of each of URLLC and eMBB.

[0101] Physics Resources

[0102] Compared to LTE, the physical resources used for NR can be configured to be flexible. A common resource block (CRB) is defined from point A, which is the reference point of the frequency radio resource unit of any NR cell, and the BWP configuration for transmission and reception of any UE is based on the CRB. In addition, when multiple SCSs are supported in any cell, the configuration of a specific carrier bandwidth for each subcarrier spacing can also be performed. In addition, PRBs and VRBs, which are radio resource allocation units for any UE, are configured for each BWP configured for the UE.

[0103] Wider bandwidth operation

[0104] Typical LTE systems support scalable bandwidth operation for any LTE CC (component carrier). This means that, depending on the frequency deployment scenario, LTE providers can configure a single LTE CC with a minimum bandwidth of 1.4 MHz to a maximum of 20 MHz. Furthermore, standard LTE UEs support the transmission / reception capability of a single LTE CC with a 20 MHz bandwidth.

[0105] However, NR is designed to support UEs with different transmit / receive bandwidth capabilities on a single wideband NR CC. Accordingly, one or more bandwidth parts (BWPs) including subdivided bandwidths need to be configured for the NR CC, such as Figure 9 As shown, flexible and wider bandwidth operation is supported by configuring and activating different bandwidth parts for each UE.

[0106] Specifically, one or more bandwidth parts may be configured by a single serving cell configured for a UE in NR, and the UE is defined as activating one downlink (DL) bandwidth part and one uplink (UL) bandwidth part to use 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 (i.e., a UE to which CA is applied), the UE is further defined as activating one downlink bandwidth part and / or one uplink bandwidth part in each serving cell to use for uplink / downlink data transmission / reception by utilizing the radio resources of the corresponding serving cell.

[0107] Specifically, an initial bandwidth part for the initial access process of the UE can be defined in the serving cell; one or more UE-specific bandwidth parts can be configured for each UE through dedicated RRC signaling, and a default bandwidth part that can be used for fallback operation can be defined for each UE.

[0108] 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 in the serving cell and the configuration of the bandwidth parts. However, NR rel-15 defines the activation and use of only one downlink (DL) bandwidth part and one uplink (UL) bandwidth part at a time.

[0109] NR paging process

[0110] Paging technology is used to attempt to receive a call to an RRC IDLE (RRC Idle) or RRC Inactive (RRC Inactive) UE, or to indicate that the UE is RRC IDLE, RRC Inactive, or RRC Connected (RRC Connected) to change system information, or to provide ETWS / CMAS (Earthquake and Tsunami Warning System / Commercial Mobile Alert System) indication to the UE. For example, an RRC IDLE UE monitors the paging channel for core network initiated (CN initiated) paging, and an RRC Inactive UE monitors the paging channel for RAN initiated paging.

[0111] Paging DRX is defined to reduce power consumption of UEs in RRC IDLE or RRC INACTIVE mode. The paging DRX cycle can be configured by the network as follows:

[0112] The default period for core network initiated paging is broadcast via system information.

[0113] The UE-specific period for core network initiated paging may be configured through NAS signaling.

[0114] The UE-specific period for RAN-initiated paging may be configured through RRC signaling.

[0115] The UE uses the shortest DRX cycle available. For example, an RRC IDLE UE uses the shortest of the default cycles for core network-initiated paging and the UE-specific cycle. Similarly, an RRC INACTIVE UE uses the shortest of the two default cycles for core network-initiated paging and the UE-specific cycle.

[0116] At the same time, the UE monitors one paging occasion (PO) per DRX cycle. A PO can consist of multiple time slots in which paging DCI is transmitted via the PDCCH monitoring attack set. A paging frame (PF) is a radio frame and can include one or more POs or the starting point of a PO. In multi-beam operation, the length of a PO is one period of beam scanning, and the UE assumes that the same paging message is repeated in all beams of the scanning mode.

[0117] The UE monitors whether a paging message is transmitted in the PO and determines based on whether a PDCCH scrambled with the P-RNTI is received in the PDCCH monitoring opportunity set of the PO.

[0118] At the same time, PF and PO are determined by the following formulas.

[0119] The system frame number (SFN) used for PF is determined by the following equation.

[0120] (SFN+PF_offset)mod T=(T div N)*(UE_ID mod N)

[0121] In addition, the index (i_s) indicating the start point of the PDCCH monitoring opportunity set for the paging DCI is determined by the following equation.

[0122] i_s=floor(UE_ID / N)mod Ns

[0123] If the parameters 'paging-search space' and 'firstPDCCH-MonitoringOccasionOfPO' are configured, the PDCCH monitoring occasion for paging is determined according to the parameters. If the corresponding parameters are not configured, the PDCCH monitoring occasion for paging is determined according to the default association.

[0124] For the default association, Ns is 1 or 2. When Ns=1, there is only one PO starting from the PF. When Ns is 2, the PO exists in the first frame (i_s=0) or the last frame (i_s=1) of the PF.

[0125] In the case of non-default association (e.g., when the paging-SearchSpace parameter is used), the UE monitors the (i_s+1)th PO starting from the first PO in the PF. The PDCCH monitoring occasions for paging that do not overlap with UL symbols are numbered sequentially, and the first PDCCH monitoring occasion for paging in the PF is set to 0.

[0126] When "firstPDCCH-MonitoringOccasionOfPO" exists, the (i_s+1)th PO is a set of "S" consecutive PDCCH monitoring occasions for paging starting from the PDCCH monitoring occasion indicated by "firstPDCCH-MonitoringOccasionOfPO".

[0127] When "firstPDCCH-MonitoringOccasionOfPO" is not present, the (i_s+1)th PO is the set of "S" consecutive PDCCH monitoring opportunities starting from the (i_s*S)th PDCCH monitoring opportunity. Here, "S" is the number of SSBs actually transmitted, as determined by "ssb-PositionsInBurst" in system information block 1. The Kth PDCCH monitoring opportunity in the PO is associated with the Kth transmitted SSB.

[0128] Furthermore, the parameters used to calculate PF and i_s are defined as follows.

[0129] T: The DRX cycle of the UE. For example, when configured by RRC or higher layers, T is determined to be the shortest of the default DRX value broadcast in the system information and the UE-specific DRX value. If RRC or higher layers do not configure UE-specific DRX, the default value applies.

[0130] N: total number of paging frames in T

[0131] Ns: Number of paging occasions used for PF

[0132] PF_offset: offset used for PF determination

[0133] UE_ID: 5G-S-TMSI mod 1024 value

[0134] The parameters N, Ns, PF_offset, first-PDCCH-MonitoringOccasionOfPO and the length of the default DRX cycle are signaled by SIB 1.

[0135] For example, if the UE does not have a 5G-S-TMSI, such as when the UE has not yet registered in the network, the UE should use the default ID, UE_ID = 0, in the equation for determining PF and i_s.

[0136] The 5G-S-TMSI is a 48-bit long string. In the above equation for the 5G-S-TMSI, the leftmost bit should be interpreted as a binary number representing the most significant bit.

[0137] In conventional NR, paging messages are transmitted using DCI formats 1-0. To this end, the base station previously indicates the area to search for paging information by indicating pagingSearchSpace in PDCCH-ConfigCommon, while previously performing BWP resource configuration on the UE.

[0138] The paging message is scrambled with a P-RNTI defined as FFFE so that all users can decode the corresponding control message. The RNTI consisting of 2 bytes is predefined in TS 38.321 as follows.

[0139] FFFF: SI-RNTI.

[0140] FFFE: P-RNTI.

[0141] FFF0~FFFD: Reserved.

[0142] 0000: Not used.

[0143] Other: RNTI (RA-RNTI, Temporary C-RNTI, C-RNTI, MCS-C-RNTI, CS-RNTI, TPC-PUCCH-RNTI, TPC-PUSCH-RNTI, TPC-SRS-RNTI, INT-RNTI, SFI-RNTI, and SP-CSI-RNTI)

[0144] A paging message that can specify a value is defined as follows in DCI format 1_0 and is scrambled with P_RNTI.

[0145] Short message indicator - 2 digits

[0146] Short Message - 8 bits. This bit field is reserved when carrying scheduling information used only for paging.

[0147] Frequency Domain Resource Allocation- When only short messages are carried, this bit field is reserved.

[0148] is the size of CORESET0.

[0149] Time domain resource allocation - 4 bits. This bit field is reserved when only short messages are carried.

[0150] VRB to PRB mapping - 1 bit. This bit field is reserved when carrying short messages.

[0151] Modulation and coding scheme - 5 bits. This field is reserved when carrying short messages.

[0152] TB scaling - 2 bits. This bit field is reserved when carrying short messages.

[0153] Reserved bits - 8 bits when operating in a cell with shared spectrum channel access; otherwise, 6 bits.

[0154] Conventional paging messages may include a short message transmission function capable of sending disaster / emergency text messages and a function capable of transitioning a UE to an active state. However, since all UEs share the P-RNTI, it is impossible to distinguish between paging messages between UEs. Therefore, even if it is not intentional, the UE may transition to an active state unless a pagingSearchSpace is physically given additionally for the transmission location. In this case, the power consumption of the UE will increase unnecessarily. To avoid this situation, one method is to pre-configure different paging search spaces in each UE. However, in limited radio resources, the area of control messages that can be transmitted is limited, so it may be difficult to always provide different paging search spaces to many UEs.

[0155] In this regard, for the purpose of UE power saving perspective, the following items are proposed.

[0156] 1) Considering the system performance, enhancements are specified for idle / inactive mode UE power saving.

[0157] a) Study and specify paging enhancements to reduce unnecessary UE paging reception without affecting legacy UEs.

[0158] b) Specify means to provide idle / inactive mode UEs with potential TRS / CSI-RS opportunities available in connected mode, thereby minimizing system overhead impact.

[0159] There is no need for always-on TRS / CSI-RS transmission by the gNodeB.

[0160] 2) Study and specify (if agreed) enhancements to power saving techniques for connected mode UEs to minimize system performance impact.

[0161] a) Study and specify (if agreed) extensions to Rel-16 DCI-based energy saving adaptation for active BWP during DRX active time, including reduced PDCCH monitoring when C-DRX is configured.

[0162] The UE should support energy saving solutions available for Rel-15 and Rel-16 and include them in the evaluation.

[0163] b) Study the feasibility and performance impact of relaxing UE measurements for RLM and / or BFD, especially for low mobility UEs with short DRX cycles / periods, and if agreed, specify the corresponding relaxations of the requirements

[0164] The method for controlling paging occasions is described in detail below with reference to relevant drawings.

[0165] Figure 10 is a view illustrating a process of performing a paging occasion by a UE according to an embodiment.

[0166] Reference Figure 10 , the UE may receive a paging message including per-UE identification information from the base station for identifying a target undergoing a paging occasion (S1000).

[0167] The newly configured paging message can include identification information about the corresponding UE, allowing paging occasions to be performed only on predetermined UEs. In other words, the paging message including the per-UE identification information used to identify the target paging occasion can be configured separately from the existing paging message. For example, the newly configured paging message can be sent to UEs that have applied the UE power saving function.

[0168] According to an example, the identification information included in the paging message may include a downlink control channel-based permanent equipment identifier (PEI) configured for each UE. Alternatively, according to another example, the identification information may be configured as a synchronization signal-based PEI (SSS-based PEI), such as SSS. Alternatively, the identification information may be configured as a reference signal-based PEI (TRS / CSI-RS-based PEI), such as TRS or CSI-RS.

[0169] In addition, the newly configured paging message may include an area that can transmit new information for UE power saving and UE ID information. Specifically, the CSI-RS feedback transmission indication, idle-inactive state transition indication, and blind decoding (BD) skip time-related configuration that causes unintentional attempts to receive control information and search space reconfiguration may be included in the field.

[0170] A paging message can be received using a search space configured separately from the search space used to receive the paging message, in which the per-UE identification information for identifying the target of the paging occasion is not included. In other words, the base station can use the separately configured search space as the space for sending the newly configured paging message. In this case, the paging message defined by the UE power saving addition operation can be configured to be sent only in the separately configured search space. Alternatively, the base station can send a control signal using a separate search space configured in the UE, which is used to perform a function different from the existing function regarding paging control.

[0171] According to the example, a paging message can be received by monitoring a paging message in a PDCCH monitoring opportunity set included in a paging opportunity (PO). For example, the UE can monitor whether a paging message is received in a DRX cycle. In other words, the UE can monitor whether there is a paging message for the corresponding UE in the PDCCH monitoring opportunity set of the PO configured in the DRX cycle. For example, the UE can monitor whether there is a signal scrambled with the P-RNTI in the corresponding PDCCH monitoring opportunity by performing blind decoding. Here, when a separate RNTI instead of the P-RNTI is applied to the newly configured paging message, the UE can monitor whether there is a signal scrambled with the RNTI.

[0172] According to an example, a PDCCH monitoring opportunity set can be configured by repeating S consecutive PDCCH monitoring opportunities M times. Here, S means the number of synchronization signal block transmissions determined based on the system information block, and M can be set to a natural number equal to or greater than 1. In other words, a PDCCH monitoring opportunity set can be configured with one or more PDCCH monitoring opportunities. In addition, a PDCCH monitoring opportunity set can be configured by repeating S PDCCH monitoring opportunities M times.

[0173] When the paging occasion is not configured as an extended PDCCH monitoring occasion, the paging occasion set may be configured with only S consecutive PDCCH monitoring occasions. Conversely, when the extended PDCCH monitoring occasion is configured, the paging occasion set may be configured with S*M PDCCH monitoring occasions by repeating S consecutive PDCCH monitoring occasions M times.

[0174] Meanwhile, M may be included in the extended PDCCH monitoring opportunity indication information and may be received from the base station. The extended PDCCH monitoring opportunity indication information may include the above-mentioned M value and may be received via higher layer signaling. Alternatively, the extended PDCCH monitoring opportunity indication information may be broadcast via system information.

[0175] If M is set to 1, or the extended PDCCH monitoring opportunity indication information is not received, the UE may configure a PDCCH monitoring opportunity set having S consecutive PDCCH monitoring opportunities and perform monitoring.

[0176] According to an example, the UEs targeted for identifying the paging occasions may be configured as a preset number of subgroups per paging occasion. When the per-UE identification information for identifying the targets of the paging occasions is based on the PEI of the downlink control channel, the PEI may be set for the subgroup of UEs in one paging occasion.

[0177] Return to reference Figure 10 , the UE may determine whether to apply a paging message based on the identification information (S1010).

[0178] The UE may compare its own identification information with identification information in a paging message including per-UE identification information for identifying a target of a paging occasion. When determining that a paging message is transmitted to the UE, the UE may perform a paging occasion corresponding to the content of the paging message.

[0179] For example, the UE may perform CSI-RS feedback transmission, idle-inactive state transition, and blind decoding skipping, resulting in an unintentional attempt to receive control information and search space reconfiguration, or the like.

[0180] Accordingly, a method and apparatus for controlling a paging operation may be provided, in which paging messages are transmitted separately to apply to different UEs sharing the same resources.

[0181] The following describes base station operations related to the above-mentioned UE operations with reference to the accompanying drawings.

[0182] Figure 11 is a view illustrating a process of controlling a paging occasion of a UE by a base station according to an embodiment.

[0183] Reference Figure 11 , the base station may configure a paging message including identification information per UE for identifying a target undergoing a paging occasion (S1100).

[0184] The newly configured paging message can include identification information about the corresponding UE, allowing paging occasions to be performed only on predetermined UEs. In other words, the base station can configure a paging message that includes per-UE identification information for identifying the target of the paging occasion separately from existing paging messages. For example, the newly configured paging message can be transmitted to a UE that has applied the UE power saving function.

[0185] According to an example, the identification information included in the paging message may include a permanent equipment identifier (PEI) based on a downlink control channel configured for each UE. Alternatively, according to another example, the identification information may be configured as a synchronization signal-based PEI (SSS-based PEI), such as SSS. Alternatively, the identification information may be configured as a reference signal-based PEI (TRS / CSI-RS-based PEI), such as TRS or CSI-RS.

[0186] In addition, the newly configured paging message may include an area that can transmit new information for UE power saving and UE ID information. Specifically, the CSI-RS feedback transmission indication, idle-inactive state transition indication, and blind decoding (BD) skip time-related configuration that causes unintentional attempts to receive control information and search space reconfiguration may be included in the field.

[0187] According to an example, the base station may scramble the newly configured paging message with the P-RNTI. Alternatively, the base station may apply a separate RNTI, rather than the P-RNTI, to the newly configured paging message and perform scrambling.

[0188] Return to reference Figure 11 , the base station may transmit a paging message to the UE (S1110).

[0189] The base station may transmit the newly configured paging message using a search space configured separately from the search space in which the paging message does not include per-UE identification information for identifying the target of the paging occasion. In other words, the base station may use the separately configured search space as the space for transmitting the newly configured paging message. In this case, the paging message defined by the UE power saving addition operation may be configured to be transmitted only in the separately configured search space. Alternatively, the base station may transmit a control signal using the separate search space configured in the UE, the control signal being used to perform a function different from the existing function regarding paging control.

[0190] According to an example, a paging message may be transmitted via a PDCCH monitoring opportunity set included in a paging opportunity (PO). In this case, the UE may monitor whether a paging message is received in the DRX cycle. In other words, the UE may monitor whether a paging message for the corresponding UE is present in the PDCCH monitoring opportunity set of the PO configured in the DRX cycle.

[0191] According to an example, the UEs used to identify the target of the paging occasion can be configured as a preset number of subgroups per paging occasion. When the per-UE identification information used to identify the target of the paging occasion is based on the PEI of the downlink control channel, the PEI can be set for the subgroup of UEs in one paging occasion.

[0192] If the base station transmits a paging message, the UE can determine whether to apply the paging message based on the identification information. The UE can compare its own identification information with the identification information in the paging message, which includes per-UE identification information for identifying the target of the paging occasion. If it is determined that the paging message is sent to the UE, the UE can perform the paging occasion corresponding to the content of the paging message.

[0193] For example, the UE may perform CSI-RS feedback transmission, idle-inactive state transition, and blind decoding skipping, thereby inadvertently attempting to receive control information and search space reconfiguration, or the like.

[0194] Therefore, a method and apparatus for controlling a paging operation in which paging messages are transmitted separately to apply to different UEs sharing the same resources may be provided.

[0195] Each embodiment related to the method for controlling paging occasions in NR is described in detail below with reference to the relevant drawings. The embodiments described below can be applied individually or in any combination.

[0196] The present disclosure provides a method for sending paging messages to different users separately, without affecting other users sharing the same resources. Specifically, the present disclosure provides a method for configuring a paging message that adds an identification message field to allow each user to identify whether a received paging message is intended for that user, a method for sending a new RNTI-based paging message that can only be received by UEs with higher versions, and a method for configuring a new paging message search space.

[0197] Embodiment 1: Method for configuring a paging message with an added identification message field

[0198] This embodiment provides a method for adding a new message field with UE identification functionality to a paging message defined in Downlink Control Information Format 1_0 (DCI Format 1_0). A UE can use this message field to identify a paging message that was not delivered to the UE. This method can be largely divided into a method using reserved bits and a method for configuring a control message in a format that is not decodable by existing UEs.

[0199] ①Use reserved bits

[0200] This method uses the 6 to 8 reserved bits in DCI 1_0 to transmit UE ID information. This information can be pre-delivered to each UE via RRC signaling. Alternatively, the UE can calculate this information based on a value predefined for each UE. In this case, existing UEs ignore the bits and proceed accordingly. In contrast, UEs equipped with UE energy-saving functions can determine whether a control message is intended for the UE based on the information in the field and proceed accordingly.

[0201] ②Configure new control information

[0202] This method is a method for introducing a new control message instead of DCI 1_0 scrambled with the existing P-RNTI. In other words, the method prohibits existing UEs from correctly receiving corresponding information by introducing a new paging message dedicated to UEs applying the UE energy saving function. The new control message may include an area in which new information for UE energy saving and UE ID information may be transmitted. Specifically, a CSI-RS feedback transmission indication, an idle-inactive state transition indication, and a blind decoding (BD) skip time-related configuration that causes an unintentional attempt to receive control information and search space reconfiguration may be included in the new control message.

[0203] Example 2: Method for applying new paging RNTI

[0204] This embodiment is a method for using a new RNTI instead of the existing P-RNTI to scramble the paging information when determining that the UE with the energy saving function applied is performing RNTI scrambling on the paging information, and for the UE with the energy saving function applied to distinguish between the paging information. This method can be largely divided into a method of introducing a paging RNTI commonly used by UEs with the energy saving function applied, and a method of pre-configuring an RNTI for each UE with the energy saving function applied to use for paging.

[0205] ①Use the new universal paging RNTI

[0206] This method introduces a new P-RNTI that is common only between UEs that have the UE power saving function applied. For example, the item can be defined as UPS-P-RNTI, and the value can be defined as, for example, FFFD, which is a reserved value. To this end, the RNTI to be used as the paging RNTI can be pre-configured in the UE through RRC signaling. In addition, when different P-RNTIs are applied, the control message structure can be changed.

[0207] ② Use a different RNTI as the paging RNTI for each user

[0208] This method is a method of pre-configuring the RNTI value used when paging in a UE to which the UE energy saving function is applied. The corresponding value can be set between 0001 and FFEF, between FFF0 and FFFD, or between 0001 and FFFD.

[0209] Example 3: Method for configuring a paging message search space

[0210] This embodiment introduces a method for differentiating UEs when configuring paging message search spaces via RRC. To this end, when UE energy saving is enabled, the UE can be configured with two or more paging message search spaces, different from conventional ones. The control message sent in each search space can perform the same or different functions.

[0211] ① Different paging message search spaces perform the same function

[0212] This method is a method that can reduce conflicts by increasing the number of patterns in the UE's paging message search space by simultaneously transmitting the same control message in two search spaces. In this case, a method for dividing control messages by standardizing the control message insertion pattern can be considered. For example, a method can be introduced to configure search spaces of the same physical size to have the same starting position and size, and to transmit a single control message in the space.

[0213] ② Different paging message search spaces perform different functions

[0214] This method is a method for transmitting control messages, in which each paging message search space performs a different function. The base station can use the additional control message search space configured in the UE to transmit a control signal that performs a function different from the existing functions related to paging control. Alternatively, as proposed in Example 1, the base station can also use it as a space for transmitting new paging messages. In this case, the control message defining the UE power saving addition operation can be presented as being transmitted only in the new paging message reception space.

[0215] 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 terms arbitrarily selected for ease of understanding, and the content of the present disclosure is applicable even when other terms with the same meaning are used.

[0216] Therefore, a method and apparatus for controlling a paging operation can be provided, in which paging messages are transmitted separately to apply to different UEs sharing the same resources. Therefore, energy consumption caused by erroneously receiving paging messages transmitted to different UEs can be saved.

[0217] The configuration of UE and base station can be combined with the above Figure 1 and Figure 11 All or some of the embodiments described are described below with reference to the accompanying drawings Figures 1 to 11 However, in order to avoid duplication of description, some of the descriptions described above will be omitted.

[0218] Figure 12 is a view showing a configuration of a UE 1200 according to an embodiment.

[0219] Reference Figure 12 According to another embodiment, UE 1200 includes a controller 1210 , a transmitter 1220 , and a receiver 1230 .

[0220] The controller 1210 controls the overall operation of the UE 1200 according to the method for controlling the paging occasion necessary for performing the above disclosure. The transmitter 1220 transmits uplink control information and data or messages to the base station via the corresponding channel. The receiver 1230 receives downlink control information and data or messages from the base station via the corresponding channel.

[0221] Receiver 1230 may receive a paging message from a base station, the paging message including per-UE identification information for identifying a target undergoing a paging occasion. The newly configured paging message may include identification information about the corresponding UE, allowing the paging occasion to be performed only on a predetermined UE. In other words, the paging message including per-UE identification information for identifying a target undergoing a paging occasion may be configured separately from the existing paging message. For example, the newly configured paging message may be transmitted to a UE to which a UE energy saving function is applied.

[0222] According to one example, the identification information included in the paging message may include a downlink control channel-based permanent equipment identifier (PEI) configured for each UE. Alternatively, according to another example, the identification information may be configured as a synchronization signal-based PEI (SSS-based PEI), such as SSS. Alternatively, the identification information may be configured as a reference signal-based PEI (TRS / CSI-RS-based PEI), such as TRS or CSI-RS.

[0223] In addition, the newly configured paging message may include new information for UE energy saving and an area where UE ID information can be transmitted. Specifically, the CSI-RS feedback transmission indication, idle-inactive state transition indication, and blind decoding (BD) skip time-related configuration that causes unintentional attempts to receive control information and search space reconfiguration may be included in the field.

[0224] A paging message may be received using a search space configured separately from the search space used to receive a paging message that does not include per-UE identification information for identifying a target for a paging occasion. In other words, the base station may use the separately configured search space as a space for transmitting a newly configured paging message. In this case, the paging message defined by the UE energy saving addition operation may be configured to be transmitted only in the separately configured search space. Alternatively, the base station may transmit a control signal for performing a function different from existing functions related to paging control using the separate search space configured in the UE.

[0225] According to an example, the receiver 1230 can receive a newly configured paging message by monitoring a paging message in a PDCCH monitoring opportunity set included in a paging opportunity (PO). For example, the controller 1210 can monitor whether a paging message is received in a DRX cycle. In other words, the controller 1210 can monitor whether there is a paging message for the corresponding UE in the PDCCH monitoring opportunity set of the PO configured in the DRX cycle. For example, the controller 1210 can monitor whether there is a signal scrambled with a P-RNTI in the corresponding PDCCH monitoring opportunity by performing blind decoding. Here, when a separate RNTI instead of a P-RNTI is applied to the newly configured paging message, the controller 1210 can monitor whether there is a signal scrambled with an RNTI.

[0226] According to one example, the UEs targeted for identifying the paging occasions may be configured as a preset number of subgroups for each paging occasion. When the per-UE identification information for identifying the targets of the paging occasions is a PEI based on a downlink control channel, the PEI may be set for the subgroup of UEs in one paging occasion.

[0227] The controller 1210 may determine whether to apply a paging message based on the identification information. The controller 1210 may compare its own identification information with the identification information in the paging message, which includes identification information of each UE used to identify the target of the paging occasion. When it is determined that the paging message is transmitted to the UE, the controller 1210 may execute the paging occasion corresponding to the content of the paging message.

[0228] For example, the controller 1210 may perform CSI-RS feedback transmission, idle-inactive state transitions, and blind decoding skipping that results in inadvertent attempts to receive control information and search space reconfiguration, or the like.

[0229] Therefore, a method and apparatus for controlling a paging operation in which paging messages are transmitted separately to apply to different UEs sharing the same resources may be provided.

[0230] Figure 13 is a view showing the configuration of a base station 1300 according to an embodiment.

[0231] Reference Figure 13 According to another embodiment, the base station 1300 includes a controller 1310 , a transmitter 1320 , and a receiver 1330 .

[0232] The controller 1310 controls the overall operation of the base station 1300 according to a method for controlling a paging occasion necessary for performing the above disclosure. The transmitter 1320 and the receiver 1330 are used to transmit or receive signals, messages, or data necessary for performing the above disclosure with the UE.

[0233] The controller 1310 may configure a paging message including per-UE identification information for identifying a target undergoing a paging occasion. The newly configured paging message may include identification information about the corresponding UE to allow the paging occasion to be performed only on a predetermined UE. In other words, the controller 1310 may configure a paging message including per-UE identification information for identifying a target undergoing a paging occasion separately from the existing paging message. For example, the newly configured paging message may be transmitted to a UE to which a UE energy saving function is applied.

[0234] According to one example, the identification information included in the paging message may include a downlink control channel-based permanent equipment identifier (PEI) configured for each UE. Alternatively, according to another example, the identification information may be configured as a synchronization signal-based PEI (SSS-based PEI), such as SSS. Alternatively, the identification information may be configured as a reference signal-based PEI (TRS / CSI-RS-based PEI), such as TRS or CSI-RS.

[0235] In addition, the newly configured paging message may include new information for UE energy saving and an area where UE ID information can be transmitted. Specifically, the CSI-RS feedback transmission indication, idle-inactive state transition indication, and blind decoding (BD) skip time-related configuration that causes unintentional attempts to receive control information and search space reconfiguration may be included in the field.

[0236] According to one example, the controller 1310 may scramble the newly configured paging message with the P-RNTI. Alternatively, the controller 1310 may apply a separate RNTI, instead of the P-RNTI, to the newly configured paging message and perform scrambling.

[0237] Transmitter 1320 can transmit a paging message to the UE. Transmitter 1320 can transmit the newly configured paging message through a search space configured separately from the search space in which the paging message that does not include per-UE identification information for identifying the target of the paging occasion is received. In other words, transmitter 1320 can use the separately configured search space as the space for sending the newly configured paging message. In this case, the paging message defined by the UE energy saving addition operation can be configured to be transmitted only in the separately configured search space. Alternatively, transmitter 1320 can send a control signal through a separate search space configured in the UE to perform a function different from the existing function related to paging control.

[0238] According to one example, a paging message may be transmitted via a PDCCH monitoring opportunity set included in a paging opportunity (PO). In this case, the UE may monitor whether a paging message is received in the DRX cycle. In other words, the UE may monitor whether a paging message for the corresponding UE is received in the PDCCH monitoring opportunity set of the PO configured in the DRX cycle.

[0239] According to one example, the UEs targeted for identifying the paging occasions may be configured as a preset number of subgroups for each paging occasion. When the per-UE identification information for identifying the targets of the paging occasions is a PEI based on a downlink control channel, the PEI may be set for the subgroup of UEs in one paging occasion.

[0240] If transmitter 1320 transmits a paging message, the UE may determine whether to apply the paging message based on the identification information. The UE may compare its own identification information with the identification information in the paging message, which includes per-UE identification information for identifying the target of the paging occasion. If it is determined that the paging message is transmitted to the UE, the UE may perform the paging occasion corresponding to the content of the paging message.

[0241] For example, the UE may perform CSI-RS feedback transmission, idle-inactive state transition, and blind decoding skipping resulting in inadvertent attempts to receive control information and search space reconfiguration, or the like.

[0242] Therefore, a method and apparatus for controlling a paging operation in which paging messages are transmitted separately to apply to different UEs sharing the same resources may be provided.

[0243] Hereinafter, a method for monitoring a paging message by a UE is described. The UE performing a paging occasion may monitor whether a paging message exists in a PDCCH monitoring occasion set included in one paging occasion.

[0244] For example, the UE monitors whether a paging message is received in the DRX cycle. In other words, the UE monitors whether a paging message for the corresponding UE is present in the PDCCH monitoring opportunity set of the PO configured in the DRX cycle. For example, the UE can monitor whether a signal scrambled with the P-RNTI is present in the corresponding PDCCH monitoring opportunity by performing blind decoding.

[0245] At the same time, the PDCCH monitoring opportunity set is configured by repeating S consecutive PDCCH monitoring opportunities M times. Here, S represents the number of synchronization signal block transmissions determined based on the system information block, and M can be set to a natural number equal to or greater than 1. In other words, the PDCCH monitoring opportunity set is configured with one or more PDCCH monitoring opportunities. In addition, the PDCCH monitoring opportunity set can be configured by repeating S PDCCH monitoring opportunities M times.

[0246] When the paging occasion is not configured as an extended PDCCH monitoring occasion, the paging occasion set can be configured to have only S consecutive PDCCH monitoring times. Conversely, when the extended PDCCH monitoring occasion is configured, the paging occasion set can be configured with S*M PDCCH monitoring occasions by repeating S consecutive PDCCH monitoring occasions M times.

[0247] Meanwhile, M may be included in the extended PDCCH monitoring opportunity indication information and received from the base station. The extended PDCCH monitoring opportunity indication information may include the above-mentioned M value and may be received via higher layer signaling. Alternatively, the extended PDCCH monitoring opportunity indication information may be broadcast via system information.

[0248] If M is set to 1, or the extended PDCCH monitoring opportunity indication information is not received, the UE configures a PDCCH monitoring opportunity set having S consecutive PDCCH monitoring opportunities and performs monitoring.

[0249] The UE can determine whether the base station has accessed a channel in the PDCCH monitoring opportunity set that includes the frequency band in which the paging message is transmitted. The UE can determine whether the base station has accessed the corresponding channel in the PDCCH monitoring opportunity set. For example, the frequency band of the channel can be a licensed band or an unlicensed band. As an example, when the frequency band is an unlicensed band, the UE can determine whether the base station has successfully occupied and accessed the channel including the frequency band as a result of performing, for example, LBT. As another example, when the frequency band is a licensed band, the UE can determine whether the base station is transmitting a signal in the frequency band and has accessed.

[0250] This is to prevent unnecessary energy consumption of the UE according to paging message monitoring by determining whether the base station transmits any signal in a frequency band in which the paging message is transmitted in the PDCCH monitoring opportunity set.

[0251] For example, upon detecting a PDCCH scrambled with a radio network temporary identifier (RNTI) other than a paging RNTI (P-RNTI) or a reference signal transmitted by a base station in a PDCCH monitoring opportunity set, the UE can determine that the base station accesses a channel. As an example, when a DMRS transmitted from a base station is received in a PDCCH monitoring opportunity set, the UE determines that the base station accesses a channel of a frequency band in which a paging message is transmitted. As another example, upon detecting a PDCCH transmitted by a base station in a PDCCH monitoring opportunity set, the UE determines that the base station accesses a channel of a frequency band in which a paging message is transmitted. Here, the PDCCH may include a signal scrambled with an RNTI other than the P-RNTI. As another example, upon receiving a paging message scrambled with a P-RNTI in a PDCCH monitoring opportunity set, the UE can determine that the base station accesses a channel.

[0252] When it is determined that the base station has accessed a channel, the UE may stop monitoring the PDCCH monitoring opportunity set for the presence of a paging message. For example, when it is determined that the base station has accessed a channel in a frequency band including the PDCCH monitoring opportunity set, the UE may stop monitoring for paging messages in subsequent PDCCH monitoring opportunities. Specifically, it is assumed that the PDCCH monitoring opportunity set consists of a total of four PDCCH monitoring opportunities from index 0 to index 3. In this case, the UE monitors whether a paging message scrambled with the P-RNTI is received in PDCCH monitoring opportunities 0 to 3.

[0253] When it is determined that the base station accesses the channel in the PDCCH monitoring occasion 1 , the UE stops the monitoring operation for detecting the paging message in the PDCCH monitoring occasions 2 and 3 .

[0254] This paging message stop operation can be applied only to a discontinuous reception (DRX) cycle including a paging opportunity in which the base station is determined to access the channel. For example, if there is a PO in a paging DRX cycle and the base station's access to the channel in the PDCCH monitoring opportunity set is detected, the UE stops the paging message monitoring operation only in the remaining PDCCH monitoring opportunities configured in the PO of the corresponding paging DRX cycle. In the subsequent paging DRX cycle, the paging message monitoring operation is resumed in the PO. In other words, the paging message monitoring stop operation according to the present disclosure is applied only in the DRX cycle and does not affect the next DRX cycle.

[0255] If the base station successfully accesses the corresponding frequency band but does not transmit a paging message to the UE, it can be considered that there is no paging message in the DRX cycle. Therefore, it is possible to stop unnecessary blind decoding in the PDCCH monitoring opportunity set in the corresponding PO to prevent power consumption.

[0256] The above-described embodiments 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 components not described in this embodiment may be supported by the above-described standard documents to clarify the technical concepts of the present disclosure. Furthermore, all terms disclosed herein may be described in the above-described standard documents.

[0257] The above embodiments may be implemented by any of various means. For example, the present embodiment may be implemented as hardware, firmware, software, or a combination thereof.

[0258] In the case of hardware implementation, the method according to this embodiment may 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.

[0259] In the case of implementation by firmware or software, the method according to this embodiment can be implemented in the form of a device, process or function for performing the above-mentioned functions or operations. The software code can be stored in a memory unit and can be driven by a processor. The memory unit can be provided inside or outside the processor and can exchange data with the processor through various well-known methods.

[0260] In addition, the terms "system", "processor", "controller", "component", "module", "interface", "model", "unit", etc. can generally refer to computer-related physical hardware, a combination of hardware and software, software, or running software. For example, the above components can be, but are not limited to, processes driven by a processor, processors, controllers, control processors, entities, execution threads, programs, and / or computers. For example, both an application running in a controller or processor and the controller or processor can be components. One or more components can be provided in a process and / or execution thread, and these components can be provided in a single device (e.g., a system, a computing device, etc.), or can be distributed across two or more devices.

[0261] The above-mentioned embodiments of the present disclosure have been described for illustrative purposes only, and those skilled in the art will understand 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 limit, but 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 appended claims, so that all technical ideas included in the scope equivalent to the claims belong to the present disclosure.

[0262] CROSS-REFERENCE TO RELATED APPLICATIONS

[0263] This application claims priority from Korean Patent Application No. 10-2020-0104374, filed on August 20, 2020, and Korean Patent Application No. 10-2021-0108070, filed on August 17, 2021, the disclosures of which are incorporated herein by reference in their entirety.< / nrcoreset>

Claims

1. A method for performing a paging operation by a UE, the method comprising: receiving a paging message, wherein the paging message includes identification information of each UE; as well as determining whether to apply the paging message based on the identification information; wherein the paging message is received through a search space configured separately from a search space for receiving a paging message lacking the identification information; The identification information includes a permanent equipment identifier (PEI) based on a downlink control channel (PDCCH); The paging message is received by monitoring the paging message in a PDCCH monitoring opportunity set included in one paging opportunity, The PEI based on the downlink control channel is equally configured for the UE in the one paging occasion.

2. A method for controlling a paging operation of a UE by a base station, the method comprising: Configuring a paging message, wherein the paging message includes identification information of each UE; as well as transmitting the paging message; wherein the paging message is transmitted through a search space configured separately from a search space for receiving a paging message lacking the identification information; The identification information includes a permanent equipment identifier (PEI) based on a downlink control channel (PDCCH); The paging message is sent via a PDCCH monitoring opportunity set included in a paging opportunity. The downlink control channel-based PEI is configured for the subgroup of UEs in the one paging occasion.

3. A UE for performing a paging operation, comprising: a receiver configured to receive a paging message, wherein the paging message includes per-UE identification information; as well as a controller configured to determine whether to apply the paging message based on the identification information; wherein the paging message is received through a search space configured separately from a search space for receiving a paging message lacking the identification information; The identification information includes a permanent equipment identifier (PEI) based on a downlink control channel (PDCCH); The paging message is received by monitoring the paging message in a PDCCH monitoring opportunity set included in one paging opportunity, The downlink control channel-based PEI is configured for the subgroup of UEs in the one paging occasion.

4. A base station for controlling a paging operation, comprising: a controller configured to configure a paging message, wherein the paging message includes per-UE identification information; as well as a transmitter configured to determine whether to apply the paging message based on the identification information; wherein the paging message is transmitted through a search space configured separately from a search space for receiving a paging message lacking the identification information; The identification information includes a permanent equipment identifier (PEI) based on a downlink control channel (PDCCH); The paging message is sent via a PDCCH monitoring opportunity set included in a paging opportunity. The downlink control channel-based PEI is configured for the subgroup of UEs in the one paging occasion.

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