Apparatus in communication system and method performed thereby

Abstract

An apparatus in a communication system and a method performed by the same are provided. The present disclosure relates to a communication method and system for converging a 5th-Generation (5G) communication system with an Internet of Things (IoT) technology to support higher data rates beyond a 4th-Generation (4G) system. The present disclosure may be applied to intelligent services based on the 5G communication technology and the IoT-related technology, such as smart home, smart building, smart city, smart car, connected car, health care, digital education, smart retail, security and security services. The present disclosure relates to a method and apparatus for performing and setting a frequency measurement for a non-connected mode terminal in a next generation mobile communication system.

Description

[0001] This application is a divisional application of a Chinese patent for invention with an application date of August 3, 2020, an application number of 202080054464.4, and an invention title of "Method and apparatus for performing frequency measurement and setting frequency measurement for non-connected mode terminals". Technical Field

[0002] The present disclosure relates to a method and apparatus for performing frequency measurement and setting frequency measurement for non-connected mode terminals in a next-generation mobile communication system. Background Art

[0003] In order to meet the demand for increased wireless data traffic since the deployment of 4G communication systems, efforts have been made to develop improved 5G or pre-5G communication systems. Therefore, 5G or pre-5G communication systems are also referred to as "beyond 4G networks" or "post-LTE systems". The 5G communication system is considered to be implemented in a higher frequency (millimeter wave) band, such as the 60 GHz band, in order to achieve higher data rates. In order to reduce the propagation loss of radio waves and increase the transmission distance, techniques such as beamforming, massive multiple-input multiple-output (MIMO), full-dimensional MIMO (FD-MIMO), array antennas, analog beamforming, and massive antennas have been discussed in the 5G communication system. In addition, in the 5G communication system, system network improvements are being developed based on advanced small cells, cloud radio access network (RAN), ultra-dense networks, device-to-device (D2D) communication, wireless backhaul, mobile networks, cooperative communication, coordinated multi-point (CoMP), receiver interference cancellation, etc. In the 5G system, hybrid FSK and QAM modulation (FQAM) and sliding window superimposed coding (SWSC) as advanced coding modulation (ACM), and filter bank multi-carrier (FBMC), non-orthogonal multiple access (NOMA), and sparse code multiple access (SCMA) as advanced access technologies have been developed.

[0004] The Internet is a human - centered network of connections where humans generate and consume information and is now evolving towards the Internet of Things (IoT), in which distributed entities such as things exchange and process information without human intervention. The Internet of Everything (IoE) has emerged, which is the combination of IoT technology and big - data processing technology through connection to cloud servers. As IoT implementation requires technical elements such as "sensing technology", "wired / wireless communication and network infrastructure", "service interface technology", and "security technology", sensor networks, machine - to - machine (M2M) communication, machine - type communication (MTC), etc. have been recently studied. Such an IoT environment can provide intelligent Internet technology services, creating new value for human life by collecting and analyzing data generated between interconnected things. IoT can be applied to various fields, including smart homes, smart buildings, smart cities, smart cars or connected vehicles, smart grids, healthcare, smart appliances, and advanced medical services through the integration and combination of existing information technology (IT) with various industrial applications.

[0005] In line with this, various attempts have been made to apply 5G communication systems to IoT networks. For example, technologies such as sensor networks, machine - type communication (MTC), and machine - to - machine (M2M) communication can be implemented through beamforming, MIMO, and array antennas. Cloud radio access network (RAN), as an application of the above - mentioned big - data processing technology, can also be considered an example of the integration of 5G technology and IoT technology. SUMMARY OF THE INVENTION

[0006]

TECHNICAL PROBLEM

[0007] In order to support services with high data rates and low transmission delays in the next - generation mobile communication system, the base station needs to quickly configure the carrier aggregation (CA) technology or dual - connection (DC) technology to the terminal. However, configuring the above - mentioned technologies to the terminal requires the frequency measurement results of the terminal. Therefore, a method for quickly receiving the frequency measurement result report from the terminal is needed.

[0008]

SOLUTION TO THE PROBLEM

[0009] According to one aspect of the present disclosure, a method performed by a terminal is provided, including: identifying whether a first frequency list is included in first information received by a Radio Resource Control (RRC) release message; in a case where the first frequency list is included in the first information, performing measurements in the RRC_IDLE mode or the RRC_INACTIVE mode based on the first frequency list; and in a case where the first frequency list is not included in the first information, performing measurements in the RRC_IDLE mode or the RRC_INACTIVE mode based on a second frequency list included in second information received by a System Information Block (SIB), wherein the measurements are performed based on a Synchronization Signal Block (SSB) configuration included in the first information or the second information.

[0010] According to another aspect of the present disclosure, a terminal is provided, including: a transceiver; and a controller configured to identify whether a first frequency list is included in first information received by a Radio Resource Control (RRC) release message, in a case where the first frequency list is included in the first information, performing measurements in the RRC_IDLE mode or the RRC_INACTIVE mode based on the first frequency list; and in a case where the first frequency list is not included in the first information, performing the measurements in the RRC_IDLE mode or the RRC_INACTIVE mode based on a second frequency list included in second information received by a System Information Block (SIB). Wherein, the measurements are performed based on a Synchronization Signal Block (SSB) configuration included in the first information or the second information.

[0011] According to another aspect of the present disclosure, a method performed by a base station is provided, including: sending first information by a Radio Resource Control (RRC) release message; and sending second information by a System Information Block (SIB); wherein, in a case where the first frequency list is included in the first information, the terminal performs measurements in the RRC_IDLE mode or the RRC_INACTIVE mode based on the first frequency list, and in a case where the first frequency list is not included in the first information, the terminal performs measurements in the RRC_IDLE mode or the RRC_INACTIVE mode based on a second frequency list included in second information received by a System Information Block (SIB). Wherein, the measurements are performed based on a Synchronization Signal Block (SSB) configuration included in the first information or the second information.

[0012] According to another aspect of the present disclosure, there is provided a base station, comprising: a transceiver; and a controller configured to send first information through a Radio Resource Control (RRC) release message; and send second information through a System Information Block (SIB); wherein, when a first frequency list is included in the first information, a terminal performs measurements in the RRC_IDLE mode or the RRC_INACTIVE mode based on the first frequency list, and wherein, when the first frequency list is not included in the first information, the terminal performs measurements in the RRC_IDLE mode or the RRC_INACTIVE mode based on a second frequency list included in the second information received through the System Information Block (SIB). Wherein, the measurements are performed based on a Synchronization Signal Block (SSB) configuration included in the first information or the second information.

[0013]

Advantageous Effects of the Invention

[0014] The present disclosure proposes a method for a terminal in the RRC_IDLE mode or the RRC_INACTIVE mode in a next-generation mobile communication system to quickly report the result of measuring the ambient frequency to a base station, thereby allowing the base station to quickly configure the CA technology or the DC technology for the terminal. Specifically, when a terminal releases the connection with the network, the base station can set configuration information for frequency measurement in the RRC message sent to the terminal, and the terminal has the ability to perform frequency measurement in the RRC_IDLE mode or the RRC_INACTIVE mode. When moving in the RRC_IDLE mode or the RRC_INACTIVE mode and performing the cell selection or reselection process, the terminal can perform frequency measurement based on the frequency measurement configuration information set in the RRC message or the system information of the serving cell where the terminal camps through the cell reselection process. In addition, the base station can quickly configure the CA technology or the DC technology for the terminal by allowing the terminal to immediately report the frequency measurement result when establishing the connection with the network. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In conjunction with the accompanying drawings, from the following detailed description, the above and other aspects, features, and advantages of certain embodiments of the present disclosure will become more apparent.

[0016] Figure 1 is a diagram showing the structure of a Long-Term Evolution (LTE) system according to an embodiment of the present disclosure.

[0017] Figure 2 is a diagram showing the structure of a radio protocol in an LTE system according to an embodiment of the present disclosure.

[0018] Figure 3 is a diagram showing the structure of a next-generation mobile communication system according to an embodiment of the present disclosure.

[0019] Figure 4It is a diagram showing the structure of a radio protocol in a next-generation mobile communication system according to an embodiment of the present disclosure.

[0020] Figure 5 It is a diagram showing the process in which a terminal in a next-generation mobile communication system according to an embodiment of the present disclosure transitions from the RRC idle mode or the RRC inactive mode to the RRC connected mode and configures the carrier aggregation technology.

[0021] Figure 6 It is a diagram showing a first embodiment according to an embodiment of the present disclosure, which enables a terminal in a next-generation mobile communication system to perform early measurements and make early measurement reports in the RRC idle mode or the RRC inactive mode.

[0022] Figure 7 It is a diagram showing a second embodiment according to an embodiment of the present disclosure, which enables a terminal in a next-generation mobile communication system to perform early measurements and make early measurement reports in the RRC idle mode or the RRC inactive mode.

[0023] Figure 8 It is a diagram showing the signal structure when a terminal performs frequency measurements on an LTE frequency in the RRC idle mode or the RRC inactive mode according to an embodiment of the present disclosure.

[0024] Figure 9 and Figure 10 They are diagrams each showing the signal structure when a terminal performs frequency measurements on an NR frequency in the RRC idle mode or the RRC inactive mode according to an embodiment of the present disclosure.

[0025] Figure 11 It is a diagram showing a method in which a terminal performs frequency measurements in the RRC idle mode or the RRC inactive mode in a network synchronized between different frequencies or cells according to an embodiment of the present disclosure.

[0026] Figure 12 It is a diagram showing the problems that occur when a terminal performs frequency measurements in the RRC idle mode or the RRC inactive mode in a network that is not synchronized between different frequencies or cells according to an embodiment of the present disclosure.

[0027] Figure 13 It is a diagram showing a first embodiment of an effective frequency measurement method in the RRC idle mode or the RRC inactive mode according to an embodiment of the present disclosure.

[0028] Figure 14 It is a diagram showing a second embodiment of an effective frequency measurement method in the RRC idle mode or the RRC inactive mode according to an embodiment of the present disclosure.

[0029] Figure 15It is a diagram showing a third embodiment of an effective frequency measurement method in the RRC idle mode or RRC inactive mode according to an embodiment of the present disclosure.

[0030] Figure 16 It is a diagram showing a fourth embodiment of an effective frequency measurement method in the RRC idle mode or RRC inactive mode according to an embodiment of the present disclosure.

[0031] Figure 17 It is a diagram showing a method for a terminal to perform frequency measurement in the RRC idle mode or RRC inactive mode in a network where the terminal is out of sync between different frequencies or cells according to an embodiment of the present disclosure.

[0032] Figure 18 It is a diagram showing an operation for a terminal to perform frequency measurement and report measurement results in the RRC idle mode or RRC inactive mode according to an embodiment of the present disclosure.

[0033] Figure 19 It is a block diagram showing the structure of a terminal according to an embodiment of the present disclosure.

[0034] Figure 20 It is a block diagram showing the structure of a base station in a wireless communication system according to an embodiment of the present disclosure. Detailed implementation manners

[0035] Before proceeding with the following detailed description, it may be advantageous to set forth definitions of certain words and phrases used throughout this patent document: The terms “including” and “comprising” and their derivatives mean including without limitation; the term “or” is inclusive and means and / or; the phrases “associated with” and “associated therewith” and their derivatives may mean including, being included within, interconnected, including, being included within, connected to or connected therewith, coupled to or coupled therewith, communicable, collaborating, interleaved, juxtaposed, proximate, bound to or having, having, etc.; and the term “controller” means any device, system, or part thereof that controls at least one operation, and such a device may be implemented in hardware, firmware, software, or some combination of at least two of them. It should be noted that the functions associated with any particular controller may be centralized or distributed, whether local or remote.

[0036] In addition, the various functions described below can be implemented or supported by one or more computer programs, each formed from computer-readable program code and embodied in a computer-readable medium. The terms "application" and "program" refer to one or more computer programs, software components, instruction sets, procedures, functions, objects, classes, instances, related data, or portions thereof suitable for implementation in appropriate computer-readable program code. The phrase "computer-readable program code" includes any type of computer code, including source code, object code, and executable code. The phrase "computer-readable medium" includes any type of medium that can be accessed by a computer, such as read-only memory (ROM), random access memory (RAM), hard disk drive, compact disc (CD), digital versatile disc (DVD), or any other type of memory. A "non-transitory" computer-readable medium does not include a wired, wireless, optical, or other communication link that transmits transitory electrical or other signals. Non-transitory computer-readable media include media that can permanently store data and media that can store data and later rewrite it, such as rewritable compact discs or erasable storage devices.

[0037] Certain words and phrases are defined throughout this patent document, and those of ordinary skill in the art should understand that, in many if not most instances, such definitions apply to both the prior and future use of such defined words and phrases.

[0038] As discussed below Figures 1 to 20 and the various embodiments used to describe the principles of the present disclosure in this patent document are merely exemplary and should not be construed as limiting the scope of the present disclosure in any way. Those skilled in the art will understand that the principles of the present disclosure can be implemented in any appropriately arranged system or device.

[0039] The following description with reference to the accompanying drawings is provided to assist in a comprehensive understanding of the various embodiments of the present disclosure defined by the claims and their equivalents. It includes various specific details that are helpful for understanding, but these are merely considered exemplary. Thus, those of ordinary skill in the art will recognize that various changes and modifications can be made to the various embodiments described herein without departing from the scope and spirit of the present disclosure. In addition, descriptions of well-known functions and structures may be omitted for clarity and conciseness.

[0040] The terms and words used in the following description and claims are not limited to their bibliographical meanings, but are used solely by the inventors to enable a clear and consistent understanding of the present disclosure. Thus, it will be apparent to those skilled in the art that the following description of the various embodiments of the present disclosure is provided for illustrative purposes only and not for the purpose of limiting the present disclosure as defined by the appended claims and their equivalents.

[0041] In describing the following disclosure, detailed descriptions of related known configurations or functions incorporated herein will be omitted when it is determined that their detailed descriptions may unnecessarily obscure the subject matter of the disclosure. Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.

[0042] In the following description, for ease of description, terms for identifying access nodes, terms for indicating network entities, terms for indicating messages, terms for indicating interfaces between network entities, terms for indicating various identification information, etc. are used. Therefore, the present disclosure is not limited by the terms provided below, and other terms indicating a subject having an equivalent technical meaning may be used.

[0043] For ease of description, the present disclosure uses terms and names defined in the 3rd Generation Partnership Project Long Term Evolution (3GPP LTE). However, the present disclosure is not limited to such terms and names, and can be equally applied to systems compliant with other standards. For ease of description, evolved Node B (eNB) and "gNB" may be used interchangeably in the present disclosure. That is, a base station described as an eNB may indicate a gNB.

[0044] The present disclosure proposes a method for a terminal in the RRC idle mode or RRC inactive mode in a next-generation mobile communication system to quickly report the result of measuring ambient frequencies to a base station, thereby allowing the base station to quickly configure carrier aggregation (CA) technology or dual connectivity (DC) technology for the terminal. Specifically, when the terminal releases its connection with the network, the base station may set configuration information for frequency measurement in the RRC message sent to the terminal, and the terminal has the ability to perform frequency measurement in the RRC idle mode or RRC inactive mode. When moving in the RRC idle mode or RRC inactive mode and performing a cell selection or reselection process, the terminal may perform frequency measurement based on the frequency measurement configuration information set in the RRC message or the system information of the serving cell in which the terminal camps through the cell reselection process. In addition, the base station may quickly configure the CA technology or DC technology for the terminal by allowing the terminal to immediately report the frequency measurement result when establishing a connection with the network.

[0045] In the present disclosure, a RRC connected mode terminal can receive an RRC message (e.g., an RRC Release message) from a base station and release the RRC connection. If the RRC message includes frequency measurement configuration information and an instruction to transition to the RRC idle mode or the RRC inactive mode, the terminal can perform frequency measurements in the RRC idle mode or the RRC inactive mode for a given duration or period of time. However, if there is no information about the list of frequencies to be measured in the frequency measurement configuration information set by the RRC message, and if the serving cell in which the terminal camps through the cell selection or reselection process broadcasts frequency measurement configuration information for frequency measurements of RRC idle mode or RRC inactive mode terminals, the terminal can perform frequency measurements by storing or considering the frequency measurement list based on this information.

[0046] As described above, the terminal can perform frequency measurements in the RRC idle mode or the RRC inactive mode. If an RRC connection needs to be established with the network, and if there is an indicator in the system information of the serving cell indicating support for frequency measurements in the RRC idle mode or the RRC inactive mode (early measurements), or if there is a valid measurement result in the terminal that meets the measurement result reporting conditions set in the frequency measurement configuration information, the RRC idle mode or RRC inactive mode terminal can send an indicator to the base station via an RRC message (e.g., an RRC Setup Complete message or an RRC Resume Complete message), which indicates the existence of the result of performing frequency measurements in the RRC idle mode or the RRC inactive mode. Once the indicator is received, the base station can send a request message (e.g., a new RRC message or a UE Information Request message) requesting the frequency measurement result to the terminal. Once the request message is received, the terminal can report the frequency measurement result as a response message (e.g., a new RRC message or a UE Information Response message) to the base station. Therefore, based on the measurement result, the base station can quickly configure the CA technology or the DC technology for the terminal.

[0047] In another method, if the terminal performs frequency measurements in the RRC inactive mode and an RRC connection needs to be established with the network, and if there is an indicator in the system information of the serving cell indicating support for frequency measurements in the RRC idle mode or the RRC inactive mode (early measurements), or if there is a valid measurement result in the terminal that meets the measurement result reporting conditions set in the frequency measurement configuration information, the RRC inactive mode terminal can report a valid frequency measurement result as an RRC message to the base station when receiving an RRC message (e.g., an RRC Resume message) containing an indicator requesting the frequency measurement result from the base station. Therefore, based on the measurement result, the base station can quickly configure the CA technology or the DC technology for the terminal.

[0048] The present disclosure proposes what configuration information a base station should send to a terminal for battery saving and efficient signaling of the terminal when setting RRC idle mode or RRC inactive mode frequency measurement configuration information for the terminal, and what configuration information the base station should send in an RRC message (e.g., an RRC Release message) or system information.

[0049] In addition, the present disclosure proposes how the terminal will perform frequency measurement on each frequency or cell to save the battery of the terminal when receiving RRC idle mode or RRC inactive mode frequency measurement configuration information through an RRC message or system information, and how the terminal will apply the frequency measurement configuration information received through the RRC message or system information when performing frequency measurement.

[0050] Figure 1 FIG. is a diagram showing the structure of a Long Term Evolution (LTE) system according to an embodiment of the present disclosure.

[0051] Reference Figure 1 , as shown in the figure, the radio access network of the LTE system is configured with next-generation base stations (evolved Node B (eNB), Node B, or base station) 1-05, 1-10, 1-15, and 1-20, a Mobility Management Entity (MME) 1-25, and a Serving Gateway (S-GW) 1-30. A User Equipment (UE) (or terminal) 1-35 can access an external network via eNBs 1-05 to 1-20 and S-GW 1-30.

[0052] In Figure 1 , eNBs 1-05 to 1-20 can correspond to traditional Node Bs in a Universal Mobile Telecommunications System (UMTS). The eNBs are connected to the UE 1-35 through a radio channel and perform more complex roles than traditional Node Bs. In the LTE system, real-time services, such as Voice over Internet Protocol (VoIP), and all user traffic can be provided through a shared channel. Therefore, a device for performing scheduling by collecting status information of the UE, such as buffer status, available transmission power status, channel status, etc., is required, and eNBs 1-05 to 1-20 can be responsible for scheduling. One eNB usually controls multiple cells. To achieve a transmission rate of 100 Mbps, the LTE system uses Orthogonal Frequency Division Multiplexing (OFDM) as a radio access technology with a bandwidth of 20 megahertz (MHz). In addition, an Adaptive Modulation and Coding (AMC) scheme for determining a modulation scheme and a channel coding rate can be applied based on the channel status of the UE. The S-GW 1-30 is a device for providing a data bearer and generates or removes a data bearer under the control of the MME 1-25. The MME is a device responsible for various control functions in addition to the mobility management function associated with the UE and can be connected to multiple base stations.

[0053] Figure 2 It is a diagram showing the structure of the radio protocol in the LTE system according to an embodiment of the present disclosure.

[0054] Refer to Figure 2 , for each of the UE and the eNB, the radio protocol of the LTE system includes Packet Data Convergence Protocol (PDCP) 2-05 and 2-40, Radio Link Control (RLC) 2-10 and 2-35, Medium Access Control (MAC) 2-15 and 2-30, and Physical Layer (PHY) 2-20 and 2-25. PDCP 2-05 and 2-40 can be responsible for IP header compression / decompression, etc. The main functions of PDCP can be summarized as follows:

[0055] - Header compression and decompression: Only Robust Header Compression (ROHC)

[0056] - Transmission of user data

[0057] - Sequential transfer (sequential transfer of upper layer Packet Data Units (PDUs) in the PDCP re-establishment procedure of Radio Link Control Acknowledged Mode (RLC AM))

[0058] - Reordering (split bearers for DC (only RLC AM supported): PDCP PDU routing for transmission, PDCP PDU reordering for reception)

[0059] - Duplicate detection (duplicate detection of lower layer Service Data Units (SDUs) in the PDCP re-establishment process for RLC AM)

[0060] - Retransmission (retransmission of PDCP SDUs during handover, and for split bearers of DC, retransmission of PDCP SDUs in the PDCP data recovery process for RLC AM)

[0061] - Encryption and decryption

[0062] - Timer-based SDU discard (timer-based SDU discard in the uplink)

[0063] RLC 2-10 and 2-35 can reconfigure the PDCP PDUs into appropriate sizes and perform ARQ, etc. The main functions of RLC can be summarized as follows:

[0064] - Data transmission (transmission of upper layer PDUs)

[0065] - Automatic Repeat Query (ARQ) (error correction through ARQ (only applicable to AM data transmission))

[0066] - Concatenation, segmentation, and reassembly (Concatenation, segmentation, and reassembly of RLC SDUs (only for unacknowledged mode (UM) and AM data transfer))

[0067] - Re-segmentation (Re-segmentation of RLC data PDUs (only for AM data transfer))

[0068] - Re-ordering (Re-ordering of RLC data PDUs (only for UM and AM data transfer))

[0069] - Duplicate detection (Duplicate detection (only for UM and AM data transfer))

[0070] - Error detection (Protocol error detection (only for AM data transfer))

[0071] - RLC SDU discard (RLC SDU discard (only for UM and AM data transfer))

[0072] - RLC re-establishment

[0073] MAC 2-15 and 2-30 can be connected to various RLC layer devices configured for a UE, and can perform multiplexing of RLC PDUs into MAC PDUs and demultiplexing of RLC PDUs from MAC PDUs. The main functions of MAC can be summarized as follows:

[0074] - Mapping (Mapping between logical channels and transport channels)

[0075] - Multiplexing and demultiplexing (Multiplexing MAC SDUs belonging to one or more different logical channels into transport blocks (TBs) transmitted to the physical layer on the transport channel / Demultiplexing transport blocks (TBs) transmitted from the physical layer on the transport channel into MAC SDUs belonging to one or more different logical channels)

[0076] - Scheduling information reporting

[0077] - Hybrid automatic repeat request (HARQ) (Error correction through HARQ)

[0078] - Priority handling between logical channels (Priority handling between logical channels of a UE)

[0079] - Priority handling between UEs (Priority handling between UEs through dynamic scheduling)

[0080] - Multimedia broadcast / multicast service (MBMS) service identification

[0081] - Transmission format selection

[0082] - Padding

[0083] The physical (PHY) layers 2-20 and 2-25 may perform operations of channel encoding and modulating higher layer data to generate OFDM symbols and transmitting the OFDM symbols to a wireless channel, or demodulating and channel decoding the OFDM symbols received via the wireless channel and transmitting the demodulated and channel decoded OFDM symbols to a higher layer.

[0084] Figure 3 FIG. is a diagram showing the structure of a next-generation mobile communication system according to an embodiment of the present disclosure.

[0085] Reference Figure 3 , as shown in the figure, the radio access network of a next-generation mobile communication system (hereinafter referred to as NR or 5G) may be configured with a next-generation base station (new radio node B (NR gNB or NR base station) 3-10 and a new radio core network (NR CN) 3-05. A user equipment (new radio user equipment (NR UE) or terminal) 3-15 may access an external network 3-35 via the NR gNB 3-10 and the NR CN 3-05.

[0086] In Figure 3 , the NR gNB 3-10 may correspond to an evolved node B (eNB) in a conventional LTE system. The NR gNB is connected to the NR UE 3-15 via a wireless channel and may provide better services compared to a conventional node B. In a next-generation mobile communication system, all user services are served through a shared channel, and thus, a device that needs to collect UE state information (such as buffer state, available transmission power state, channel state, etc.) and perform scheduling is required, and the NR NB 3-10 is responsible for these. One NR gNB generally controls multiple cells. In order to achieve high-speed data transmission when compared with currently used LTE, a bandwidth greater than or equal to the conventional maximum bandwidth may be required, and orthogonal frequency division multiplexing (OFDM) is used as a radio access technology, and beamforming technology is additionally used. In addition, an adaptive modulation and coding (AMC) scheme that determines a modulation scheme and a channel coding rate may be applied based on the channel state of the UE. The NR CN 3-05 may support mobility, configure bearers, or configure quality of service (QoS). The NR CN 3-05 is a device that is responsible for various control functions in addition to the mobility management function associated with the UE 3-15 and may be connected to multiple base stations. In addition, a next-generation mobile communication system may interoperate with a conventional LTE system, and the NR CN 3-05 may be connected to the MME 3-25 via a network interface. The MME 3-25 may be connected to the eNB 3-30 that is a conventional base station.

[0087] Figure 4 FIG. is a diagram showing the structure of a radio protocol in a next-generation mobile communication system according to an embodiment of the present disclosure.

[0088] Reference Figure 4 The radio protocol of the next-generation mobile communication system is configured with NR Service Data Adaptation Protocol (SDAP) 4-01 and 4-45, NR PDCP 4-05 and 4-40, NR RLC 4-10 and 4-35, and NR MAC 4-15 and 4-30 for each of the UE and the NR base station.

[0089] The main functions of NR SDAP 4-01 and 4-45 may include the following partial functions:

[0090] - Transmission of user data (transmission of user plane data)

[0091] - Mapping between QoS flows and data radio bearers (DRBs) in the downlink (DL) and uplink (UL)

[0092] - Marking QoS flow identifiers (IDs) in the DL and UL (marking QoS flow IDs in DL and UL packets)

[0093] - Mapping of reflected QoS flows to DRBs for UL SDAP PDUs (mapping of reflected QoS flows to DRBs for UL SDAP PDUs)

[0094] For each PDCP layer device, or for each bearer, or for each logical channel, the UE may receive, via a radio resource control (RRC) message, a configuration associated with whether to use the header of the SDAP layer device or whether to use the functions of the SDAP layer device. When the SDAP header is configured, the UE is guided to update or reconfigure the mapping information between the data bearer and the QoS flows in the uplink and downlink through a one-bit non-access stratum (NAS) reflected QoS indicator (NAS reflected QoS) and a one-bit AS reflected QoS indicator (AS reflected QoS) of the SDAP header. The SDAP header may include QoS flow ID information indicating QoS. The QoS information may be used as data processing priorities to support smooth services, scheduling information, etc.

[0095] The main functions of NR PDCP 4-05 and 4-40 may include the following partial functions:

[0096] - Header compression and decompression: Only ROHC

[0097] - Transmission of user data

[0098] - In-sequence delivery (in-sequence delivery of upper-layer PDUs)

[0099] - Out-of-sequence delivery (out-of-sequence delivery of upper-layer PDUs)

[0100] - Reordering (for reordering of received PDCP PDUs)

[0101] - Duplicate detection (duplicate detection of lower layer SDUs)

[0102] - Retransmission (retransmission of PDCP SDUs)

[0103] - Encryption and decryption

[0104] - Timer-based SDU discard (timer-based SDU discard in the uplink)

[0105] The reordering function of NR PDCP 4-05 and 4-40 can indicate the function of reordering PDCP PDUs received in sequence from the lower layer according to the PDCP sequence number (SN). The reordering function can include the function of delivering the reordered data in order to the higher layer, the function of delivering the data immediately regardless of the order, the function of performing reordering and recording the lost PDCP PDUs, the function of reporting the status of the lost PDCP PDUs to the transmission side, and the function of requesting retransmission of the lost PDCP PDUs.

[0106] The main functions of NR RLC 4-10 and 4-35 can include the following partial functions:

[0107] - Data transfer (transfer of upper layer PDUs)

[0108] - In-sequence delivery (in-sequence delivery of upper layer PDUs)

[0109] - Out-of-sequence delivery (out-of-sequence delivery of upper layer PDUs)

[0110] - ARQ (error correction by ARQ)

[0111] - Concatenation, segmentation and reassembly (concatenation, segmentation and reassembly of RLC SDUs)

[0112] - Resegmentation (resegmentation of RLC data PDUs)

[0113] - Reordering (reordering of RLC data PDUs)

[0114] - Duplicate detection

[0115] - Error detection (protocol error detection)

[0116] - RLC SDU discard

[0117] - RLC re-establishment

[0118] The in-sequence delivery function of the NR RLC device can indicate the function of delivering the RLC SDUs received from the lower layer to the higher layer in sequence. The in-sequence delivery function can include the function of reconstituting the RLC SDUs segmented from an original single RLC SDU and delivering the RLC SDUs, can include the function of reordering the received RLC PDUs based on the RLC sequence number (SN) or PDCP sequence number (SN), can include the function of performing reordering and recording the lost RLC PDUs, can include the function of reporting the status of the lost RLC PDUs to the transmission side, can include the function of requesting retransmission of the lost RLC PDUs, can include the function of delivering only the RLC SDUs before the lost RLC SDU to the higher layer if the lost RLC SDU exists, can include the function of delivering all the received RLC SDUs before the timer starts to the higher layer even if the lost RLC SDU exists if the timer expires, or can include the function of delivering all the most recently received RLC PDUs to the higher layer even if the lost RLC SDU exists if a predetermined timer expires. The RLC PDUs can be processed in the order of arrival (regardless of the sequence number) and can be delivered to the PDCP device randomly (out-of-sequence delivery). In the case of segmentation, a single RLC PDU is reconfigured by receiving the segments stored in the buffer or to be received in the future, and the RLC PDU can be delivered to the PDCP device. NR RLC layers 4-10 and 4-35 may not include the concatenation function, and this function can be performed by NR MAC layers 4-15 and 4-30, or can be replaced by the multiplexing function of NR MAC layers 4-10 and 4-35.

[0119] The out-of-sequence delivery function of the NR RLC device can indicate the function of delivering the RLC SDUs received from the lower layer to the higher layer immediately in any order. The out-of-sequence delivery function can include the function of reconstituting the RLC SDUs segmented from an original single RLC SDU and delivering the RLC SDUs, and can include the function of storing the RLC SN or PDCP SN of the received RLC PDUs, performing reordering, and recording the lost RLC PDUs.

[0120] NR MAC layers 4-15 and 4-30 can be connected to multiple NR RLC layer devices configured for a single UE, and the main functions of NR MAC layers 4-15 and 4-30 can include a part of the following functions:

[0121] - Mapping (mapping between logical channels and transport channels)

[0122] - Multiplexing / demultiplexing (multiplexing / demultiplexing of MAC SDUs)

[0123] - Scheduling Information Report

[0124] - HARQ (Error correction through HARQ)

[0125] - Priority handling between logical channels (Priority handling between logical channels of a UE)

[0126] - Priority handling between UEs (Priority handling between UEs through dynamic scheduling)

[0127] - MBMS Service Identity

[0128] - Transmission Format Selection

[0129] - Padding

[0130] The NR PHY layer 4-20 and 4-25 can perform operations of channel encoding and modulating higher layer data to generate OFDM symbols and sending the OFDM symbols to the radio channel, or demodulating and channel decoding the OFDM symbols received via the radio channel and sending the demodulated and channel decoded OFDM symbols to the higher layer.

[0131] In the next generation mobile communication system, the UE performs frequency measurements while performing the cell selection or reselection process in the RRC idle mode or RRC inactive mode. The above frequency measurements performed during the cell selection or reselection process can refer to the intra-frequency measurements of the frequencies set by the gNB or broadcast in the serving cell, or the serving cell or Pcell measurements. However, except for the intra-frequency measurements or serving cell measurements, the inter-frequency measurements are not performed, and the results of the frequency measurements are not reported to the network separately. However, when the frequency measurement configuration information for the RRC idle mode or RRC inactive mode is set by the gNB in the RRC message (e.g., RRCRelease message) or received through the system information, or when the frequency measurement configuration information for the RRC idle mode or RRC inactive mode is indicated in the system information of the serving cell or the resident cell, the UE can also perform the inter-frequency measurement process. If the UE has stored valid measurement results that meet the predetermined conditions, the UE can quickly report the frequency measurement results when establishing a connection with the network.

[0132] In addition, as described below, even in the RRC connected mode, the UE can receive frequency measurement configuration information and perform frequency measurement procedures. The frequency measurement configuration information for the RRC connected mode can be set only in an RRC message (e.g., an RRCReconfiguration message), while the frequency measurement configuration information for the RRC idle mode or the RRC inactive mode can be set for the UE via an RRC message (e.g., an RRCRelease message) or broadcast to the UE in the system information. In particular, in the case where the frequency measurement configuration information for the RRC idle mode or the RRC inactive mode is set via an RRC message (different from the information set in the system information), a duration value or a timer value specifying the duration for which the UE measures the frequency can be set, and area information specifying the area where the UE measures the frequency (e.g., list information of cell identifiers for each frequency) can be set.

[0133] In addition, as described below, even in the RRC connected mode, the UE can receive frequency measurement configuration information and perform frequency measurement procedures. When the UE finds and camps on a suitable cell through the cell reselection procedure and then transitions to the RRC connected mode through the RRC connection establishment procedure, the gNB can set for the RRC connected mode UE which frequencies (e.g., a list of frequencies) or which frequency bands are to be measured, which order to use for measurement through the priority setting for each frequency, which beam is to be measured, which filtering method will be used to measure the frequency strength (e.g., L1, L2, or L3 filtering method, or which calculation method and which coefficients will be used for measurement), which event or condition will be used to start the frequency measurement, which criteria will be used for the frequency measurement to compare with the current serving cell (or the current camped frequency), which event or condition will be applied to report the result of the frequency measurement, which criteria or conditions need to be met to report the frequency compared with the current serving cell (or the current camped frequency), or which period will be applied to report the result of the frequency measurement. The UE measures the frequency according to the frequency configuration set by the gNB as described above and reports the result of the frequency measurement to the gNB according to the corresponding event or condition. Then, using the frequency measurement result received from the UE, the gNB can determine whether to apply the CA technology or the DC technology to the UE.

[0134] A method is disclosed herein. In a next-generation mobile communication system, the UE performs frequency measurement in the RRC idle mode or the RRC inactive mode before transitioning to the RRC connected mode. The UE sends an indicator indicating the existence of the measurement result to the gNB when establishing a connection with the network, or the gNB requests the UE to report the measurement result. Then the UE enters the RRC connected mode and quickly reports the result of the frequency measurement. Therefore, based on the result measured by the UE in the RRC idle mode or the RRC inactive mode, the gNB can quickly configure the CA technology or the DC technology for the UE.

[0135] Specifically, when transitioning an RRC-connected mode UE that has established a connection with the network to RRC idle mode or RRC inactive mode, the gNB can set frequency information (or multiple frequencies), time (or duration) information, and / or area information (or cell list) for frequency measurements in RRC idle mode or RRC inactive mode for the UE via an RRC message, and can also instruct the UE to perform frequency measurements in RRC idle mode or RRC inactive mode. Additionally, whenever moving and when performing a cell reselection operation, the UE can obtain the system information of the newly camped cell, and based on the system information, can perform processes such as continuing or terminating frequency measurements, extending the measurement duration (e.g., restarting a timer), reporting frequency measurement results, discarding frequency measurement results, or updating frequency configuration information in RRC idle mode or RRC inactive mode.

[0136] In the present disclosure, a bearer can include a signaling radio bearer (SRB) and a data radio bearer (DRB). Additionally, a UM DRB represents a DRB that operates in an unacknowledged mode (UM) using an RLC layer device, and an AM DRB represents a DRB that operates in an acknowledged mode (AM) using an RLC layer device.

[0137] Figure 5 It is a diagram showing the process of a terminal transitioning from RRC idle mode or RRC inactive mode to RRC connected mode and configuring carrier aggregation technology in a next-generation mobile communication system according to an embodiment of the present disclosure.

[0138] In Figure 5 this, for a predetermined reason, a base station (hereinafter, gNB) can transition a terminal in RRC connected mode that has already established a connection with the network (hereinafter, UE) to RRC idle mode or RRC inactive mode. The predetermined reason may be a lack of scheduling resources of the gNB or a suspension of data transmission / reception with the UE within a predetermined time.

[0139] The gNB can send an RRCRelease message to the UE to instruct the UE to transition to RRC idle mode or RRC inactive mode (5-05). According to an embodiment, an indicator (suspend-config) included in the RRCRelease message can indicate that the UE transitions to RRC inactive mode, and if the indicator (suspend-config) is not included in the RRCRelease message, the UE can transition to RRC idle mode.

[0140] When a network connection is required due to a predefined reason, a UE that has transitioned to the RRC idle mode or the RRC inactive mode can perform a random access procedure, receive a random access response, request RRC connection establishment, receive RRC messages, and establish an RRC connection (5-10, 5-15, 5-20, 5-25, 5-30, 5-35, and 5-40).

[0141] The UE establishes reverse transmission synchronization with the gNB through the random access procedure and sends an RRCSetupRequest message to the gNB (5-25). The RRCSetupRequest message may contain the UE's identifier, the reason for establishing the connection (establishmentCause), etc.

[0142] The gNB sends an RRCSetup message for the UE to establish an RRC connection (5-30). The RRCSetup message may contain at least one of the configuration information for each logical channel, the configuration information for each bearer, the configuration information for the PDCP layer device, the configuration information for the RLC layer device, and the configuration information for the MAC layer device.

[0143] The RRCSetup message may allocate a bearer identifier (e.g., an SRB identifier or a DRB identifier) for each bearer and indicate the configuration of the PDCP layer device, the RLC layer device, the MAC layer device, and / or the PHY layer device for each bearer. In addition, the RRCConnectionSetup message may set the length of the PDCP sequence number used in the PDCP layer device for each bearer (e.g., 12 bits or 18 bits), and may set the length of the RLC sequence number used in the RLC layer device (e.g., 6 bits, 12 bits, or 18 bits). In addition, the RRCConnectionSetup message may indicate whether to use a header compression and decompression protocol for each PDCP layer device of each bearer in the uplink or downlink, and may indicate whether to perform an integrity protection or authentication process. In addition, it may indicate whether to perform out-of-order delivery in the PDCP layer device.

[0144] The UE that has established an RRC connection sends an RRCSetupComplete message to the gNB (5-40). The RRCSetupComplete message may contain a control message called SERVICE REQUEST, in which the UE requests the establishment of a bearer for a given service from the AMF or the MME. The gNB may send the service request message contained in the RRCSetupComplete message to the AMF or the MME, and the AMF or the MME may determine whether to provide the service requested by the UE.

[0145] If it is determined to provide the UE-requested service, the AMF or MME sends a message called INITIAL CONTEXT SETUP REQUEST to the gNB. The initial context setup request message may contain information such as quality of service (QoS) information to be applied to the setup of the DRB and security-related information to be applied to the DRB (e.g., security keys, security algorithms).

[0146] The gNB sends and receives SecurityModeCommand messages and SecurityModeComplete messages to and from the UE to establish security, and when the security setup is complete, the gNB sends an RRCConnectionReconfiguration message (5-45) to the UE.

[0147] The RRCConnectionReconfiguration message may allocate a bearer identifier (e.g., SRB identifier or DRB identifier) to each bearer and indicate the configuration of the PDCP layer device, RLC layer device, MAC layer device, and / or PHY layer device for each bearer. In addition, the RRCConnectionReconfiguration message may set the length of the PDCP sequence number used in the PDCP layer device for each bearer (e.g., 12 bits or 18 bits), and may set the length of the RLC sequence number used in the RLC layer device (e.g., 6 bits, 12 bits, or 18 bits). In addition, the RRCConnectionSetup message may indicate whether to use a header compression and decompression protocol for each PDCP layer device of each bearer in the uplink or downlink, and may indicate whether to perform an integrity protection or verification process. In addition, it may indicate whether to perform out-of-order delivery in the PDCP layer device.

[0148] In addition, the RRCConnectionReconfiguration message may contain the configuration information of the DRB for which user data is to be processed, and the UE sets up the DRB by applying the above information and then sends an RRCConnectionReconfigurationComplete message (5-50) to the gNB. The gNB that has completed the establishment of the DRB with the UE may send an INITIAL CONTEXT SETUP COMPLETE message to the AMF or MME, thus completing the connection (5-50).

[0149] When the above process is completed, the UE sends and receives data to and from the gNB via the core network (5-55 and 5-60). According to some embodiments, the data transmission process mainly consists of three operations: RRC connection establishment, security establishment, and DRB establishment. In addition, for some reason, the gNB may send an RRCConnectionReconfiguration message to the UE to re-execute, add, or change settings (5-65).

[0150] The RRCConnectionReconfiguration message may include frequency measurement configuration information (e.g., a list of frequencies to be measured, the duration of measuring the frequencies, the conditions for measuring the frequencies, the conditions for reporting the frequencies after frequency measurement, the cell identifier for reporting the frequencies, etc.).

[0151] The UE performs frequency measurements according to the frequency measurement configuration information, and when a predetermined condition is met (e.g., if the signal strength of a specific frequency is better than a certain reference (e.g., threshold), or if the signal strength of the current serving cell (frequency) is less than a certain reference (e.g., threshold)), the UE may report the results of the frequency measurements to the gNB (5-60).

[0152] When receiving the frequency measurement results, the gNB may insert Scell configuration information into the RRCReconfiguration message (5-65) based on the frequency measurement results and send it to the UE to configure carrier aggregation (CA) technology for the UE. Alternatively, the gNB may insert secondary cell group configuration information into the RRCReconfiguration message (5-65) and send it to the UE to configure dual connectivity (DC) technology for the UE.

[0153] In the case of configuring CA technology for the UE, the gNB may transition the UE to an active, inactive, or idle state by using a MAC control element (MAC CE).

[0154] The process of the gNB configuring CA technology or DC technology for the UE can be summarized as follows. First, the UE establishes a connection with the gNB, and the gNB sets frequency measurement configuration information for the RRC-connected mode UE. Then, the UE performs frequency measurements based on the frequency measurement configuration information and reports the frequency measurement results to the gNB. In addition, the gNB may set the configuration information of additional Scells as an RRC message to configure CA technology for the UE based on the UE's frequency measurement results, and may make these Scells active, idle, or inactive through MAC CE. In addition, the gNB may set secondary cell group configuration information based on the UE's frequency measurement results to configure DC technology for the UE.

[0155] As described above, when the gNB configures the CA technology or the DC technology for the UE, the UE needs to enter the RRC connected mode, receive the frequency measurement configuration information, perform the frequency measurement, and report the measurement result. Therefore, the measurement report is executed very late, causing the CA technology or the DC technology to be configured very late. Thus, to improve this problem, the present disclosure proposes a method for the UE to effectively perform frequency measurement in the RRC idle mode or the RRC inactive mode and report the frequency measurement result once the connection with the network is established.

[0156] Figure 6 FIG. is a diagram showing a first embodiment according to an embodiment of the present disclosure, which enables a terminal to perform early measurement and make an early measurement report in the RRC idle mode or the RRC inactive mode in a next-generation mobile communication system.

[0157] In a first embodiment of the present disclosure, when the frequency measurement configuration information is set by an RRCRelease message or system information, the base station (gNB) may set a plurality of frequency measurement groups for the terminal (UE) to perform frequency measurement.

[0158] According to the first embodiment, the UE capable of performing frequency measurement and quickly reporting the frequency measurement result in the RRC idle mode or the RRC inactive mode may be a UE corresponding to one or more of the following cases.

[0159] 1. Any UE whose capability supports the method of performing early frequency measurement and reporting early frequency measurement results in the RRC idle mode or the RRC inactive mode.

[0160] 2. In the RRC idle mode or the RRC inactive mode UE, any UE that receives the configuration information indicating frequency measurement in the RRC idle mode or the RRC inactive mode when the gNB transfers the UE from the RRC connected mode to the RRC idle mode or the RRC inactive mode through an RRC message. For example, in the RRC idle mode or the RRC inactive mode, any UE to which the frequency configuration information for frequency measurement, the measurement duration (e.g., timer value), or the area configuration information (e.g., cell identifier list) is set.

[0161] In Figure 6In [the scenario], a UE in the RRC connected mode (6-05) can be transitioned by the gNB to the RRC idle mode or the RRC inactive mode (6-15) due to a predefined reason (e.g., when there is no data transmission / reception at a certain time). When transitioning the mode of the UE, the gNB can send an RRC message (6-10). For example, the gNB can send an RRCRelease message containing an indicator (suspend-config) instructing the UE to transition to the RRC inactive mode, or can send an RRCRelease message without the indicator (suspend-config) to instruct the UE to transition to the RRC idle mode. The above RRC message (e.g., the RRCRelease message) can contain the first frequency configuration information to be applied when the UE performs early measurements in the RRC idle mode or the RRC inactive mode. The first frequency configuration information can have information about the frequency to be measured and the first timer value. The first timer value can indicate the duration or the timer value (e.g., T331) for performing frequency measurements in the RRC idle mode or the RRC inactive mode. When the RRCRelease message instructs frequency measurements in the RRC idle mode or the RRC inactive mode, the UE can perform frequency measurements while the timer is running and can stop frequency measurements when the timer expires.

[0162] When the UE performs early measurements in the RRC idle mode or the RRC inactive mode, the conditions for starting frequency measurements can include at least one of the following conditions (6-30).

[0163] 1. If the received RRCRelease message contains an indicator for performing frequency measurements in the RRC idle mode or the RRC inactive mode, and if the frequency information to be measured and the duration (e.g., the timer value) for measuring the frequency are set, then the UE can start the timer and perform frequency measurements according to the frequency information.

[0164] 2. If the received RRC Release message contains an indicator to perform frequency measurements in RRC idle mode or RRC inactive mode, and if only the duration for measuring the frequency (e.g., timer value) is set without frequency information, the UE may start a timer, perform a cell selection or reselection procedure, and obtain system information (6 - 12) from the serving cell where the UE is resident. The system information may contain second frequency configuration information to be applied when the UE performs early measurements in RRC idle mode or RRC inactive mode. If the frequency information to be measured in RRC idle mode or RRC inactive mode is broadcast in the system information, the UE may perform frequency measurements based on the frequency information. If new second frequency configuration information for the UE to perform measurements in RRC idle mode or RRC inactive mode is broadcast in the system information of another cell to which the UE moves and resides in newly, the UE may perform frequency measurements based on the new second frequency configuration information.

[0165] As described above, the UE may start and perform frequency measurements in RRC idle mode or RRC inactive mode. If the UE moves to and resides in a new cell and obtains system information, and if the obtained system information does not contain an indicator indicating support for frequency measurements in RRC idle mode or RRC inactive mode, the UE may stop frequency measurements while still running the first timer. After moving to another cell, if the system information of that cell has an indicator indicating support for frequency measurements in RRC idle mode or RRC inactive mode, and if the first timer is still running, the UE may restart frequency measurements by using the first frequency configuration information set in the RRC Release message as suggested above or the second system information in the system information. In the system information, an indicator indicating support for LTE frequency measurements and / or an indicator indicating support for NR frequency measurements may be defined.

[0166] When one or more of the above conditions are met, the UE may start early measurements in RRC idle mode or RRC inactive mode. When performing frequency measurements, the RRC idle mode or RRC inactive mode UE stores valid measurement results that meet a predetermined condition. Based on the configuration information set in the RRC Release message or broadcast in the system information, the UE may determine whether the frequency measurement results that meet the predetermined condition are valid.

[0167] In addition, when a connection to the network needs to be established for data transmission and reception, the UE may send Message 3 (e.g., RRCSetupRequest or RRCResumeRequest message) to the gNB while performing a random access procedure (6-35), identify the success of the random access procedure by receiving Message 4 (e.g., RRCSetup or RRCResume message) from the gNB (6-40), and transition to the RRC connected mode (6-45).

[0168] If the system information (e.g., SIB2) received by the UE before establishing a connection in the current cell contains an indicator indicating support for frequency measurements in the RRC idle mode or RRC inactive mode, or an indicator indicating that frequency measurement results in the RRC idle mode or RRC inactive mode can be received, and if the UE has valid frequency measurement results, the UE may send Message 5 (e.g., RRCSetupComplete message or RRCResumeComplete message) to the gNB indicating that the UE has frequency measurement results in the RRC idle mode or RRC inactive mode.

[0169] For example, when the UE has valid frequency measurement results that meet a predetermined condition, the UE may send Message 5 (e.g., RCSetupComplete or RRCResumeComplete) containing an indicator that indicates that early measurements have been performed in the RRC idle mode or RRC inactive mode and that there are frequency measurement results to be reported. For this indicator included in Message 5, a new indicator for indicating the existence of early frequency measurement results may be defined, or an indicator that has already been defined in the RRC message (RCSetupComplete or RRCResumeComplete) may be reused to indicate the existence of useful information in the UE (6-50). When Message 5 indicates frequency measurement results in the RRC idle mode or RRC inactive mode, indicators for measurement results for LTE frequencies and indicators for measurement results for NR frequencies may be defined and indicated separately.

[0170] When it is recognized from Message 5 that the UE has performed early measurements in the RRC idle mode or RRC inactive mode and there are measurement results to be reported, the gNB may send a message requesting a measurement result report to the UE in order to quickly receive frequency measurement results (6-55). For example, the gNB may newly define UEinformationRequest with a DL-DCCH message, and by using this message, request a frequency measurement result report from the UE. Once this message is received, the UE may report the early frequency measurement results (6-65) to the gNB. For example, upon receiving this message, the UE may redefine the UEInformationResponse message with a UL-DCCH message and report the frequency measurement results by using this message. The frequency measurement results may include measurement results of the serving cell / frequency (e.g., NR-SS RSRP / RSRQ), measurement results of neighboring cells / frequencies around the serving cell / frequency, measurement results of neighboring cells / frequencies that the UE can measure, measurement results of cells / frequencies instructed to be measured, etc. Alternatively, the gNB may define an indicator in the RRCReconfiguration message and request the frequency measurement results from the UE by using it. When this message is received, the UE may report the early frequency measurement results (6-65) to the gNB. For example, when this message is received, the UE may report the frequency measurement results by using the RRCReconfigurationComplete message. Alternatively, the UE may define new fields for reporting the frequency measurement results in the UL-DCCH message and use them.

[0171] Figure 7 FIG. is a diagram showing a second embodiment according to an embodiment of the present disclosure, which enables a terminal to perform early measurements and make early measurement reports in the RRC_IDLE mode or RRC_INACTIVE mode in a next-generation mobile communication system.

[0172] The first embodiment described above can be applied at least in part to the second embodiment of the present disclosure, and when the UE performs frequency measurement in the RRC idle mode or the RRC inactive mode, the gNB can use the RRC Release message to set the first frequency measurement configuration information to be applied. Based on the first frequency configuration information or the second frequency configuration information of the system information, the UE can perform frequency measurement in the RRC idle mode or the RRC inactive mode. When the UE establishes a connection with the network for data transmission and reception, the gNB can send an RRC message (e.g., RRC Resume message) containing an indicator requesting the frequency measurement result to the UE. Once the indicator requesting the frequency measurement result is received and once there is a valid frequency measurement result, the UE can construct an RRC message (e.g., RRC Resume Complete message) with the valid frequency measurement result and send the message to the gNB to report the frequency measurement result.

[0173] In Figure 7 when the RRC-connected mode UE receives the first frequency measurement configuration information and an instruction to release the RRC connection and transition to the RRC idle mode or the RRC inactive mode from the gNB, the UE can perform frequency measurement within the time or duration set above in the RRC idle mode or the RRC inactive mode. In addition, when the second frequency measurement configuration information for frequency measurement of the RRC idle mode or RRC inactive mode UE is broadcast in the cell where the UE camps through the cell reselection process, the UE can receive the broadcast information and perform frequency measurement.

[0174] When the UE attempts to re - establish a connection with the network in the RRC idle mode or RRC inactive mode, and when the cell used for the connection supports reporting early frequency measurement results (e.g., when the system information has a relevant indicator), the UE can perform a random access procedure, send Message 3 (e.g., RRCResumeRequest), and receive Message 4 (e.g., RRCResume message) from the gNB that contains an indicator requesting to report frequency measurement results (7 - 40). Once the indicator for reporting frequency measurement results is received, and once there are valid frequency measurement results, the UE can construct an RRC message (e.g., RRCResumeComplete message) with the valid frequency measurement results and send this message to the gNB to report the frequency measurement results (7 - 50). When receiving the frequency measurement results, when sending an RRC message (e.g., RRCReconfiguration message) or MAC control information (MAC control element (MAC CE)) to the UE, the gNB can send CA technology configuration information or DC technology configuration information, enabling the UE to quickly re - activate, change, or newly set up the CA technology or DC technology (7 - 40). Therefore, the frequency measurement result reporting can be performed faster than in the first embodiment.

[0175] Meanwhile, details of the first frequency configuration information set by the gNB in the RRCRelease message and the second frequency configuration information broadcast in the system information are disclosed below, such that in the first or second embodiment, the UE can save battery and effectively perform the frequency measurement process in the RRC idle mode or RRC inactive mode.

[0176] The first frequency configuration information set in the RRC message (e.g., setting RRC connection mode frequency measurement in the RRCReconfiguration message, setting RRC idle mode or RRC inactive mode frequency measurement in the RRCRelease message) can include one or more of the following multiple configuration information types.

[0177] - The first target frequency list for LTE frequency measurement

[0178] - The first target SSB (Synchronization Signal Block) frequency list for NR frequency measurement

[0179] - The list of target cells (including cell identifiers) to be measured and reported for each frequency: When measuring a frequency, the UE can measure signals only in cells operating at that frequency corresponding to the cell identifiers included in the cell list. Then, if a given condition is met, the UE can store the measurement results and report them to the network.

[0180] - Threshold information as a criterion to be measured and reported for each frequency: If a signal with a cell identifier included in the cell list is measured at a signal strength higher than the threshold, the UE may consider it as a valid measurement result, store it, and report the frequency measurement result when connecting to the network later.

[0181] - First configuration information for SSB measurement for each frequency: Auxiliary information that can be set to help the UE easily perform SSB measurement for each frequency, and the auxiliary information may include one or more of the following multiple configuration information types.

[0182] ■ smtc (SSB block measurement time configuration) configuration information: Time configuration information for SSB frequency measurement, including the duration, offset, or period of SSB transmission.

[0183] ■ ssbSubcarrierSpacing configuration information: Information including the frequency spacing of SSB measurement

[0184] ■ ssb-ToMeasure configuration information: SSB identifier information measured between SSBs

[0185] ■ nrofSS-BlocksToAverage: Parameter information for deriving cell signal strength

[0186] ■ absThreshSS-BlocksConsolidation: Parameter information for deriving cell signal strength

[0187] - First method for reporting frequency measurements for each frequency (e.g., RSRP, RSRQ, beam measurement results, beam identifiers, multiple beam measurement results, or multiple beam identifiers): The type of measurement results for each frequency or cell to be reported by the UE can be instructed. For example, it is possible to instruct to report RSRP or RSRQ, instruct to report beam measurement results, instruct to report beam identifiers with valid signal strength, or instruct to report multiple beam measurement results or multiple beam identifiers with valid signal strength. In addition, it is possible to instruct to report the measurement results or beam identifiers of the beam with the best signal strength.

[0188] - First derive SSB-IndexFromCell configuration information: If this indicator is set to true when performing in-frequency measurements, it means that when deriving the SSB identifier of the SSB block in the smtc configuration information of other cells to be measured in the frequency, the timing of the current PCell or serving cell can be used as a reference (reference timing). Therefore, the UE can immediately know the SSB identifier of the frequency to be measured without reading the Physical Broadcast Channel (PBCH), thus saving the UE power consumed in frequency measurements and enabling early measurements. If the indicator is set to false, the UE is required to synchronize with the cell of the frequency to be measured and derive each SSB identifier by reading the PBCH of the SSB block. In addition, if inter-frequency measurements need to be performed due to the frequency to be measured, and if the indicator is set to true, it means that if any cell of the frequency to be measured is synchronized, the synchronized cell can be used as a reference timing when performing SSB measurements on other cells of that frequency, and it also means that the SSB identifier can be derived based on that timing. If the indicator is false, the UE can synchronize with each cell of that frequency and perform SSB measurements.

[0189] - First area configuration information: This is the configuration information for the area where the UE will perform frequency measurements in RRC idle mode or RRC inactive mode, and may include, for example, a list of cells for each frequency (a list containing cell identifiers).

[0190] - First timer (e.g., validity timer) value or duration: This is a timer indicating the duration for which the UE will perform frequency measurements in RRC idle mode or RRC inactive mode. For example, when the first timer value or duration is set in the RRC Release message, based on the frequency configuration information set in the first frequency configuration information or the second frequency configuration information, the UE starts the first timer and performs frequency measurements in RRC idle mode or RRC inactive mode. When establishing a connection with the network, once the UE receives the RRC Setup message or RRC Resume message from the gNB, it can consider itself to have transitioned to the RRC connected mode, thus stopping the first timer. In addition, when exceeding the first area (e.g., validity area), the UE can stop the first timer. If the first timer stops, the UE can release the frequency configuration information, stop the frequency measurements, and / or discard the frequency measurement results.

[0191] - Second timer value or duration: To confirm the validity of the frequency measurement result, the gNB may set a second timer value in the first frequency configuration information. The second timer can be used to indicate the duration for determining the validity of the frequency measurement result. It can be determined that the stored frequency measurement result value is only valid while the second timer is running. If the second timer expires, the stored frequency measurement result value may be discarded and not reported to the gNB. Additionally, the second timer can be driven for each UE, and when the first timer indicating the frequency measurement duration expires or when the frequency measurement stops, the second timer can be started. When the second timer expires, the stored frequency measurement result can be determined to be no longer valid and thus discarded. When the UE receives a request from the gNB to report the frequency measurement result, or when the UE attempts to send the frequency measurement result to the gNB in an RRC message while the second timer is running, the second timer can be stopped. Additionally, the second timer can be driven for each frequency or cell, and when the first timer indicating the frequency measurement duration expires or when the frequency measurement stops, a new timer can be started. In another method, whenever frequency measurements are performed for each cell or frequency and then new frequency measurement results are stored for each cell or frequency, the second timer corresponding to each cell or frequency can be started or restarted. Additionally, when the second timer expires, the stored frequency measurement results for the cell or frequency for which the second timer is running can be determined to be no longer valid and discarded. Additionally, when the UE receives a request from the gNB to report the frequency measurement result, or when the UE attempts to send the frequency measurement result to the gNB in an RRC message while the second timer is running, the second timer can be stopped.

[0192] - Reference frequency or cell list for SSB measurement for each frequency: This is the configuration information of the frequency or cell that is synchronized with the current gNB or frequency serving as the timing reference when performing frequency measurements on the frequencies or cells set in the frequency list for LTE frequency measurement or the synchronization signal block (SSB) frequency list for NR frequency measurement. When performing frequency measurement configuration, the UE can synchronize with one of the frequencies or cells set in the reference frequency or cell list and then perform frequency measurements on other frequencies.

[0193] The second frequency configuration information set in the system information proposed here can include one or more of the following multiple configuration information types. Different from the first frequency configuration information, the second frequency configuration information may not include the first timer configuration information, the first area configuration information, or the second timer configuration information.

[0194] - Second target frequency list for LTE frequency measurement (frequency list for UE frequency measurement in RRC idle mode or RRC inactive mode, or measurement configuration information for neighboring cells, or other frequencies to camp on when the UE selects or reselects a cell)

[0195] - Second target SSB (Synchronization Signal Block) frequency list for NR frequency measurement (frequency list for UE frequency measurement in RRC idle mode or RRC inactive mode, or measurement configuration information for neighboring cells, or other frequencies to camp on when the UE selects or reselects a cell)

[0196] - List of target cells to be measured and reported for each frequency (including cell identifiers): When measuring a frequency, the UE can measure signals corresponding to cell identifiers included in the cell list only in cells operating on that frequency. Then, if a given condition is met, the UE can store the measurement result and report it to the network.

[0197] - Threshold information as a criterion to be measured and reported for each frequency: If a signal with a cell identifier included in the cell list is measured with a signal strength higher than the threshold, the UE can consider it as a valid measurement result, store it, and report the frequency measurement result when connecting to the network later.

[0198] - Second configuration information for SSB measurement for each frequency: Auxiliary information that can be set to help the UE easily perform SSB measurement for each frequency, and the auxiliary information can include one or more of the following multiple configuration information types.

[0199] ■ Second smtc (SSB block measurement time configuration) configuration information: Time configuration information for SSB measurement for a frequency, including duration, offset, or period for transmitting SSB.

[0200] ■ ssbSubcarrierSpacing configuration information: Information including the frequency spacing for SSB measurement

[0201] ■ ssb-ToMeasure configuration information: SSB identifier information measured between SSBs

[0202] ■ nrofSS-BlocksToAverage: Parameter information for deriving cell signal strength

[0203] ■ absThreshSS-BlocksConsolidation: Parameter information for deriving cell signal strength

[0204] - Second method for reporting frequency measurements for each frequency (e.g., RSRP, RSRQ, beam measurement results, beam identifiers, multiple beam measurement results, or multiple beam identifiers): The type of measurement results for each frequency or cell to be reported by the UE can be instructed. For example, it is possible to instruct to report RSRP or RSRQ, instruct to report beam measurement results, instruct to report beam identifiers with effective signal strength, or instruct to report multiple beam measurement results or multiple beam identifiers with effective signal strength. In addition, it is possible to instruct to report the measurement results or beam identifiers of the beam with the best signal strength.

[0205] - Second deriveSSB-IndexFromCell configuration information: If this indicator is set to true when performing in-frequency measurements, it means that when deriving the SSB identifier of the SSB block in the smtc configuration information of other cells to be measured in the frequency, the timing of the current PCell or serving cell can be used as a reference (reference timing). Therefore, the UE can immediately know the SSB identifier of the frequency to be measured without reading the physical broadcast channel (PBCH), thus saving the UE power consumed in frequency measurements and enabling early measurements. If the indicator is set to false, the UE is required to synchronize with the cell of the frequency to be measured and derive each SSB identifier by reading the PBCH of the SSB block. In addition, if inter-frequency measurements need to be performed due to the frequency to be measured, and if the indicator is set to true, it means that if any cell of the frequency to be measured is synchronized, the synchronized cell can be used as a reference timing when performing SSB measurements on other cells of that frequency, and it also means that the SSB identifier can be derived based on that timing. If the indicator is false, the UE can synchronize with each cell of that frequency and perform SSB measurements.

[0206] Figure 8 FIG. is a diagram showing a signal structure when a terminal performs frequency measurements on an LTE frequency in the RRC idle mode or RRC inactive mode according to an embodiment of the present disclosure.

[0207] The LTE frequency can represent the frequency in which an LTE base station or an NR base station operates a cell having an LTE system, and the structure of the signal transmitted by the base station at the LTE frequency can be as Figure 8 shown.

[0208] In Figure 8Among them, the base station can send a signal with a system bandwidth (BW) of 8-05 for the first LTE frequency 8-10, and the UE must read the signal according to the entire system bandwidth of the LTE frequency. The signal of the LTE frequency uses the subcarrier spacing defined for all or most frequencies except for broadcast services or specific services (such as MBMS), and transmits the SSB with the same period, duration, or offset at a predetermined frequency position (for example, six physical resource blocks (PRBs) in the middle of the system bandwidth). The channel reference signal (CRS) 8-20 can be evenly transmitted according to a predetermined rule.

[0209] When performing LTE frequency measurement, the UE that performs the RRC idle mode or RRC inactive mode frequency measurement proposed here can first read the signal with the predetermined system bandwidth of the LTE frequency, and then find the SSB signal at the predetermined position. In addition, since the SSB signal uses the subcarrier spacing defined for all or most frequencies and has the same periodicity, duration, or offset, the UE can quickly synchronize and find the SSB signal. Then, based on the SSB signal, the UE can read the master information block (MIB) signal and perform frequency measurement by measuring the evenly transmitted CRS signal. Since the CRS is always evenly transmitted on the LTE frequency, the UE has the advantage of quickly finding the CRS transmission resource and performing early frequency measurement. Alternatively, the UE can measure the SSB signal of the LTE frequency and perform frequency measurement. Alternatively, the indicator set in the RRC Release message or system information indicates whether to measure the SSB signal or the CRS signal in the case of the LTE frequency, and the UE can perform frequency measurement according to this indicator. In addition, when the predetermined conditions set in the first frequency information or the second frequency information are met, the frequency measurement result can be reported based on a predetermined method.

[0210] Figure 9 and Figure 10 are diagrams each showing the signal structure when the terminal performs frequency measurement of the NR frequency in the RRC idle mode or RRC inactive mode according to an embodiment of the present disclosure.

[0211] The NR frequency can represent the frequency at which the NR base station or the LTE base station operates a cell with the NR system, and the structure of the signal transmitted by the base station at the NR frequency can be as Figure 9 and 10 shown.

[0212] In Figure 9In this case, the base station may transmit a signal with a system bandwidth (BW) 9-05 for the first NR frequency 9-01, and the UE may read the signal not according to the entire system bandwidth of the NR frequency, but according to a partial bandwidth (BWP) 9-10 or 9-20. In the NR system, the system bandwidth of each frequency is very wide, such that if the UE reads all of the system bandwidth, a large amount of battery consumption may occur, and the base station operates multiple partial bandwidths for each frequency. Therefore, the UE may read a signal with a specific partial bandwidth (e.g., an initial partial bandwidth) of each frequency, find the SSB to be synchronized, and measure the signal of the SSB. When operating the frequency, the base station may use different subcarrier spacings for each partial bandwidth or each frequency, and transmit SSBs with different periods, durations, or offsets at a predetermined frequency position (e.g., 12 PRBs in the middle of the partial bandwidth). In addition, different from the LTE frequency, the CRS 8-20 may not be transmitted. Since the base station operates multiple partial bandwidths for the NR frequency with a very wide bandwidth, CRS transmission may bring a huge overhead to the signal transmitted by the base station. For each of the multiple partial bandwidths, the SSB signal may or may not be transmitted. However, for a specific partial bandwidth (e.g., the initial partial bandwidth), the SSB signal is always transmitted, such that an RRC idle mode or RRC inactive mode UE can synchronize the signal with the specific partial bandwidth, obtain system information, and camp.

[0213] As described above, in the NR frequency, different subcarrier spacings may be used for each frequency. In addition, since SSB signals with different periods, durations, or offsets are transmitted, the UE may need to search for the SSB signal for a long time to find the SSB signal of each frequency and find different periods, durations, or offsets. Therefore, the UE needs to calculate the period, duration, or offset of the SSB signal through complex derivation, and thus, this process may cause a large amount of battery consumption of the UE.

[0214] Therefore, as Figure 10As shown, in the present disclosure, it is proposed to set the smtc configuration information (or smtc configuration information or smtc information) of the frequency to be measured in the first frequency configuration information set using the RRC message or in the second frequency configuration information broadcast using the system information, so that the UE can easily perform frequency measurement. The smtc configuration information may include an offset 10-21, a duration 10-22, and / or a period 10-23 of the frequency to be measured, and the reference timing of these parameters 10-21, 10-22, and 10-23 included in the smtc configuration information may be based on the timing 10-05 of the PCell or serving cell 10-01. For example, when the UE is configured to perform frequency measurement in the RRC connection, the UE can perform frequency measurement by applying the smtc information 10-21, 10-22, and 10-23 based on the timing of the current PCell 10-01 (e.g., system frame number (SFN) 0) 10-05. In another example, when the UE is configured to perform frequency measurement in the RRC idle mode or RRC inactive mode, the UE can perform frequency measurement by applying the smtc information 10-21, 10-22, and 10-23 based on the timing of the serving cell 10-01 where the UE is currently camped (e.g., SFN 0) 10-05.

[0215] In the RRC connected mode, the detailed process for the UE to perform frequency measurement based on the smtc information is as follows.

[0216] - When receiving the first frequency configuration information with the RRC message from the base station in the RRC connected mode, the UE prepares to perform frequency measurement on the frequency or cell set in the first frequency configuration information.

[0217] - When attempting to measure a specific frequency in the above frequency list and when the smtc information for that frequency is included, the UE applies the smtc information based on the timing of the PCell 10-01 currently connected to it. That is, the UE can measure the SSB signal in the SSB signal transmission part by applying the offset 10-21 of the smtc information and also applying the duration 10-22 of the smtc information based on the SFN 0 of the current PCell 10-01, and continuously measure the SSB signal at the time point of the next SSB signal transmission by applying the period 10-23 of the smtc information. Since the smtc information has been set for this frequency, based on the smtc information and the reference timing of the current PCell, the UE can immediately perform frequency measurement for this frequency. Therefore, there is no need to synchronize the frequency, search for the SSB signal from the beginning, and derive the parameter values of the periodicity, offset, and duration, thereby being able to reduce the battery consumption of the UE and achieve early frequency measurement.

[0218] In the RRC idle mode or the RRC inactive mode, the detailed process for the UE to perform frequency measurements based on smtc information is as follows.

[0219] - In the RRC idle mode or the RRC inactive mode, when receiving the first frequency configuration information with an RRC message or the second frequency configuration information with the system information of the serving cell where the UE camps through the cell selection or reselection process, the UE prepares to perform frequency measurements on the frequencies or cells set in the first or second frequency configuration information.

[0220] - When attempting to measure a specific frequency in the above frequency list and when there is smtc information for that frequency, in the RRC idle mode or the RRC inactive mode, the UE applies the smtc information based on the timing of the serving cell 10-01 where the UE camps through the cell selection or reselection process. That is, the UE can measure the SSB signal in the SSB signal transmission part by applying the offset 10-21 of the smtc information based on the SFN 0 of the current serving cell 10-01 and also applying the duration 10-22 of the smtc information, and can continuously measure the SSB signal at the time point of the next SSB signal transmission by applying the period 10-23 of the smtc information. Since the smtc information has been set for this frequency, based on the smtc information and the reference timing of the current serving cell, the UE can immediately perform frequency measurements for this frequency. Therefore, there is no need to synchronize the frequency, search for the SSB signal from the beginning, and derive the parameter values of the period, offset, and duration, thus reducing the battery consumption of the UE and enabling early frequency measurements.

[0221] The UE performing frequency measurements in the RRC idle mode or the RRC inactive mode is characterized in that when performing measurements on NR frequencies, it first finds the SSB signal of a specific partial bandwidth (e.g., the initial partial bandwidth) of the NR frequency. Since for different frequencies, the SSB signal can use different subcarrier spacings and have different periods, durations, and / or offsets, the UE can continuously search for the SSB signal and derive the parameter values of the period, duration, and / or offset through calculation. Different from measuring the CRS of LTE frequencies, for NR frequencies, the UE performs frequency measurements of the SSB signal based on the derived parameter values. In addition, when the predetermined conditions set in the first or second frequency information are met, the UE can report the frequency measurement results through a predetermined method.

[0222] The method for performing the frequency measurements proposed for LTE frequencies or NR frequencies can be extended and applied as a method for the UE to perform frequency measurements in the RRC idle mode, the RRC inactive mode, or the RRC connected mode.

[0223] In addition, when attempting to perform a frequency measurement, if the frequency to be measured is an LTE frequency, the UE can use the method proposed in Figure 8 to perform the frequency measurement, and if the frequency to be measured is an NR frequency, it can also use the method proposed in Figure 9 or 10 to perform the frequency measurement.

[0224] Figure 11 is a diagram showing a method for a terminal in a network that synchronizes between different frequencies or cells to perform a frequency measurement in the RRC idle mode or the RRC inactive mode according to an embodiment of the present disclosure.

[0225] In Figure 11 , a UE that transmits / receives data in the RRC connected mode in the current cell 11-01 (the first cell) can receive an RRC Release message from the base station of the current cell 11-01, transition to the RRC idle mode or the RRC inactive mode, and move while performing a cell selection or reselection process. The RRC Release message may include first frequency configuration information. In addition, the RRC idle mode or RRC inactive mode UE can camp on a suitable cell through the cell selection or reselection process and obtain system information. The UE can receive second frequency configuration information in the system information.

[0226] If the received RRC Release message includes first frequency configuration information, the UE can drive a timer by applying the first timer value information of the first frequency configuration information and start an early frequency measurement in the RRC idle mode or the RRC inactive mode. In addition, if the first frequency configuration information includes first area configuration information, the UE can identify the identifier of the camped cell and determine whether to perform an early frequency measurement in the RRC idle mode or the RRC inactive mode.

[0227] If the UE is in the service area of the first cell 11-01, the UE may perform early frequency measurements in the RRC idle mode or the RRC inactive mode based on the first frequency configuration information received in the RRC Release message or the second frequency configuration information broadcast as system information by the first cell 11-01. That is, when the UE attempts to measure the first frequency 11-10 in the above frequency list, and when the first frequency configuration information received from the first cell contains the first smtc configuration information or the second frequency configuration information received in the system information of the first cell contains the second smtc configuration information, in the RRC idle mode or the RRC inactive mode, the UE applies such smtc configuration information based on the timing of the serving cell (i.e., the first cell) 11-01 on which the UE camps through the cell selection or reselection process. That is, the UE may measure the SSB signal in the SSB signal transmission part by applying the offset of the smtc information based on the SFN 0 of the current serving cell 11-01 and also applying the duration of the smtc information, and continuously measure the SSB signal at the time point of the next SSB signal transmission by applying the periodicity of the smtc information. Since the smtc information has been set for this frequency, based on the smtc information and the reference timing of the current serving cell, the UE can immediately perform frequency measurement for this frequency. Therefore, there is no need to synchronize the frequency, search for the SSB signal from the beginning, and derive the parameter values of the periodicity, offset, and duration, thereby being able to reduce the battery consumption of the UE and achieve early frequency measurement. If the smtc configuration information is not included for this frequency, the UE may not perform RRC idle mode or RRC inactive mode frequency measurement for this frequency to reduce battery consumption. Optionally, even when there is no smtc configuration information, the UE may also perform RRC idle mode or RRC inactive mode frequency measurement by being implemented to synchronize the frequency, search for the SSB signal from the beginning, and derive the parameter values of the periodicity, offset, and duration.

[0228] If the UE moves from the first cell 11-01 to the service area of the second cell 11-02 and camps on the second cell 11-02, the UE can perform RRC idle mode or RRC inactive mode frequency measurements based on the first frequency configuration information received in the RRC Release message or the second frequency configuration information broadcast as system information by the second cell 11-02. That is, when the UE attempts to measure the second frequency 11-20 in the above frequency list, and when the first frequency configuration information received from the first cell contains the first smtc configuration information or the second frequency configuration information received in the system information of the second cell contains the second smtc configuration information, in the RRC idle mode or RRC inactive mode, the UE applies this smtc configuration information based on the timing of the serving cell (i.e., the second cell) 11-02 on which the UE camps through the cell selection or reselection process. That is, the UE can measure the SSB signal in the SSB signal transmission part by applying the offset of the smtc information based on the SFN 0 of the current serving cell 11-02 and also applying the duration of the smtc information, and continuously measure the SSB signal at the time point of the next SSB signal transmission by applying the periodicity of the smtc information. Since the smtc information has been set for this frequency, based on the smtc information and the reference timing of the current serving cell, the UE can immediately perform frequency measurement for this frequency. Therefore, there is no need to synchronize the frequency, search for the SSB signal from the beginning, and derive the parameter values of the periodicity, offset, and duration, thereby being able to reduce the battery consumption of the UE and achieve early frequency measurement. If this frequency does not contain the smtc configuration information, the UE can refrain from performing RRC idle mode or RRC inactive mode frequency measurements for this frequency to reduce battery consumption. Optionally, even when there is no smtc configuration information, the UE can also perform RRC idle mode or RRC inactive mode frequency measurements by being implemented to synchronize the frequency, search for the SSB signal from the beginning, and derive the parameter values of the periodicity, offset, and duration.

[0229] Figure 12 FIG. is a diagram illustrating problems that occur when a terminal performs frequency measurements in an RRC idle mode or RRC inactive mode in a network where different frequencies or cells are not synchronized according to an embodiment of the present disclosure.

[0230] In Figure 12Among them, a UE that transmits / receives data in the RRC connected mode in the current cell 12-01 (the first cell) can receive an RRC Release message from the base station of the current cell 12-01, transition to the RRC idle mode or the RRC inactive mode, and move while performing the cell selection or reselection process. The RRC Release message may include first frequency configuration information. In addition, a UE in the RRC idle mode or the RRC inactive mode can camp on a suitable cell through the cell selection or reselection process and obtain system information. The UE can receive second frequency configuration information in the system information.

[0231] If the received RRC Release message includes first frequency configuration information, the UE can drive a timer by applying the first timer value information of the first frequency configuration information and start early frequency measurement in the RRC idle mode or the RRC inactive mode. In addition, if the first frequency configuration information includes first area configuration information, the UE can identify the identifier of the camped cell and determine whether to perform early frequency measurement in the RRC idle mode or the RRC inactive mode.

[0232] If the UE is in the service area of the first cell 12-01, the UE may perform early frequency measurements in the RRC idle mode or the RRC inactive mode based on the first frequency configuration information received in the RRC Release message or the second frequency configuration information broadcast as system information by the first cell 12-01. That is, when the UE attempts to measure the first frequency 12-10 in the above frequency list, and when the first frequency configuration information received from the first cell contains the first smtc configuration information or the second frequency configuration information received in the system information of the first cell contains the second smtc configuration information, the UE applies such smtc configuration information at the timing of the serving cell (i.e., the first cell) 12-01 on which the UE camps through the cell selection or reselection process in the RRC idle mode or the RRC inactive mode. That is, the UE may measure the SSB signal in the SSB signal transmission part by applying the offset of the smtc information based on the SFN 0 of the current serving cell 12-01 and also applying the duration of the smtc information, and continuously measure the SSB signal at the time point of the next SSB signal transmission by applying the periodicity of the smtc information. Since the smtc information has been set for this frequency, based on the smtc information and the reference timing of the current serving cell, the UE can immediately perform frequency measurement for this frequency. Therefore, there is no need to synchronize the frequency, search for the SSB signal from the beginning, and derive the parameter values of the periodicity, offset, and duration, thereby being able to reduce the battery consumption of the UE and achieve early frequency measurement. If this frequency does not contain the smtc configuration information, the UE may not perform RRC idle mode or RRC inactive mode frequency measurement for this frequency to reduce the battery consumption. Optionally, even when there is no smtc configuration information, the UE may also perform RRC idle mode or RRC inactive mode frequency measurement by being implemented to synchronize the frequency, search for the SSB signal from the beginning, and derive the parameter values of the periodicity, offset, and duration.

[0233] If the UE moves from the first cell 12-01 to the service area of the second cell 12-02 and camps on the second cell 12-02, the UE can perform RRC idle mode or RRC inactive mode frequency measurements based on the first frequency configuration information received in the RRC Release message or the second frequency configuration information broadcast as system information by the second cell 12-02. That is, when the UE attempts to measure the second frequency 12-20 in the above frequency list, and when the first frequency configuration information received from the first cell contains the first smtc configuration information or the second frequency configuration information received in the system information of the second cell contains the second smtc configuration information, the UE applies such smtc configuration information at the timing of the serving cell (i.e., the second cell) 12-02 on which the UE camps through the cell selection or reselection process. That is, the UE can measure the SSB signal in the SSB signal transmission part by applying the offset of the smtc information based on the SFN 0 of the current serving cell 12-02 and also applying the duration of the smtc information, and continuously measure the SSB signal at the time point of the next SSB signal transmission by applying the periodicity of the smtc information.

[0234] However, in Figure 12 , there is a time synchronization mismatch between the first cell 12-01 and the second cell 12-02. Therefore, when measuring the second frequency 12-20 in the second cell, if the first smtc information of the second frequency 12-20 included in the first frequency configuration information received in the RRC Release message of the first cell is applied, there may be a problem that frequency measurement cannot be performed due to asynchronous timing. This is because the first smtc information of the second frequency 12-20 included in the first frequency configuration information received in the RRC Release message of the first cell is information set based on the reference timing of the first cell. If the UE applies the first smtc information in the area of the second cell based on the reference timing of the second cell, the part of the frequency measurement will not match like the gap between the timing of the first cell and the timing of the second cell. Therefore, for the second frequency, the UE may not perform RRC idle mode or RRC inactive mode frequency measurements properly.

[0235] The following describes a method for effective RRC idle mode or RRC inactive mode frequency measurements, which can solve the above problem of frequency measurement failure caused by Figure 12 the asynchronous timing in and minimize the battery consumption of the UE.

[0236] Figure 13 is a diagram showing a first embodiment of an effective frequency measurement method in RRC idle mode or RRC inactive mode according to an embodiment of the present disclosure.

[0237] In Figure 13 this case, the base station or cell can set the configuration information for RRC idle mode or RRC inactive mode frequency measurement for the UE by using the first frequency measurement configuration information 13-10 in the RRC Release message or the second frequency measurement configuration information 13-20 in the system information.

[0238] If the received RRC Release message contains the first frequency configuration information, the UE can drive a timer by applying the first timer value information of the first frequency configuration information and start RRC idle mode or RRC inactive mode frequency measurement (i.e., early measurement). In addition, if the first frequency configuration information contains the first area configuration information, the UE can identify the identifier of the cell in which the UE camps through the cell selection or reselection process and can determine whether to perform early frequency measurement in RRC idle mode or RRC inactive mode. If the first frequency configuration information does not contain the first frequency list information to be measured and if the second frequency configuration is broadcast in the system information of the camped cell, the UE can perform RRC idle mode or RRC inactive mode frequency measurement based on the second frequency configuration information (e.g., the second frequency list information), store the valid measurement results, and when an RRC connection is established later, as Figure 6 described in 7, report the stored measurement results to the network.

[0239] In Figure 13 the first embodiment of the efficient RRC idle mode or RRC inactive mode frequency measurement method shown, the UE can receive the first frequency configuration information through the RRC Release message, transition to the RRC idle mode or RRC inactive mode, and perform frequency measurement. In addition, the UE can receive the second frequency configuration information through the system information of the cell in which the UE camps through the cell selection or reselection process.

[0240] The first embodiment is characterized in that the UE receives the first frequency configuration information and / or the second frequency configuration information, gives priority to the first frequency configuration information when performing RRC idle mode or RRC inactive mode frequency measurement, and performs frequency measurement only based on the first frequency configuration information. In addition, with respect to the configuration information not included in the first frequency configuration information, the UE can consider the second frequency configuration information to perform frequency measurement.

[0241] For example, the UE can receive the first frequency configuration information in the RRC Release message 13-10 from the first cell, transition to the RRC idle mode or RRC inactive mode, and then receive the second frequency configuration information in the system information 13-20 from the first cell or the new second cell through the cell selection or reselection process.

[0242] The first frequency list of the first frequency configuration information 13-10 may include frequency 1 (13-01), frequency 2 (13-02), frequency 3 (13-03), frequency 4 (13-04), frequency 5 (13-05), and frequency 6 (13-06) as target frequencies to be measured. Among these frequencies, only frequency 1 (13-01), frequency 2 (13-02), frequency 3 (13-03), and frequency 5 (13-05) can be configured with threshold information serving as the standard for measurement and reporting for each frequency, the first configuration information for SSB measurement for each frequency, or the first reporting method for the measurement report for each frequency.

[0243] The second frequency list of the second frequency configuration information 13-20 may include frequency 3 (13-03), frequency 4 (13-04), frequency 5 (13-05), frequency 6 (13-06), frequency 7 (13-07), and frequency 8 (13-08) as target frequencies to be measured. Among these frequencies, only frequency 3 (13-03), frequency 4 (13-04), frequency 7 (13-07), and frequency 8 (13-08) can be configured with threshold information serving as the standard for measurement and reporting for each frequency, the second configuration information for SSB measurement for each frequency, or the second reporting method for the measurement report for each frequency.

[0244] When receiving the first frequency configuration information 13-10 or the second frequency configuration information 13-20, the UE may select the frequencies to be measured and then apply one of the following methods to determine the frequency configuration to be applied to each frequency.

[0245] -Method 1-1 (13-51): The UE preferentially considers the first frequency configuration information 13-10 to perform frequency measurements. Therefore, the UE can perform frequency measurements only on the frequencies 13-51 (i.e., frequency 1 (13-01), frequency 2 (13-02), frequency 3 (13-03), frequency 4 (13-04), frequency 5 (13-05), and frequency 6 (13-06)) set in the first frequency list by applying the frequency measurement configuration information for each frequency set in the first frequency configuration information 13-10 (e.g., threshold information used as a standard for measurement and reporting for each frequency, the first configuration information for SSB measurement for each frequency, or the first reporting method for measurement reporting for each frequency), determine valid frequency measurement results, construct the results to be reported, and store the constructed results. Specifically, in Method 1-1, based on the reference timing of the serving cell where the UE camps through the cell selection or reselection process, the UE can perform frequency measurements by applying the first configuration information (e.g., periodicity, offset, and / or duration of smtc) for SSB measurement for each frequency. If there is no first configuration information for SSB measurement for the target frequency to be measured, the UE may not perform the measurement of that frequency to reduce battery consumption. In an alternative method, even when there is no first configuration information (e.g., periodicity, offset, and / or duration of smtc) for SSB measurement for the frequency, the UE can perform RRC idle mode or RRC inactive mode frequency measurements by being implemented as a synchronous frequency, searching for SSB signals from the start, and deriving the parameter values of periodicity, offset, and duration. In another alternative method, the UE can store the reference timing of the cell from which it receives the RRCRelease message, and based on the stored timing, perform measurements by applying the first configuration information to SSB measurement for each frequency. In this Method 1-1, the UE performs frequency measurements only based on the first frequency configuration information, so that it is not necessary to read a large amount of system information, thereby reducing the battery consumption of the UE.

[0246] -Method 1-2 (13-52): The UE preferentially considers the first frequency configuration information 13-10 to perform frequency measurements. Thus, the UE can perform frequency measurements only on the frequencies 13-52 set in the first frequency list (i.e., frequency 1 (13-01), frequency 2 (13-02), frequency 3 (13-03), frequency 4 (13-04), frequency 5 (13-05), and frequency 6 (13-06)) by applying the frequency measurement configuration information for each frequency (e.g., threshold information used as a standard for measurement and reporting for each frequency, first configuration information for SSB measurement for each frequency, or first reporting method for measurement reporting for each frequency), determine valid frequency measurement results, construct the results to be reported, and store the constructed results. Specifically, in Method 1-2, based on the reference timing of the serving cell where the UE camps through the cell selection or reselection process, the UE can perform frequency measurements by applying the first configuration information (e.g., periodicity, offset, and / or duration of smtc) for SSB measurement for each frequency. If there is no first configuration information for SSB measurement of the target frequency to be measured (e.g., frequency 4 (13-04)), but if the second frequency configuration information received in the system information contains the second configuration information for SSB measurement of this frequency, then based on the reference timing of the serving cell where the UE camps through the cell selection or reselection process, the UE can perform frequency measurements by applying the second configuration information (e.g., periodicity, offset, and / or duration of smtc) for SSB measurement of this frequency (e.g., frequency 4 (13-04)). If there is neither the first configuration information nor the second configuration information for SSB measurement of the target frequency to be measured, the UE can refrain from performing measurements on this frequency to reduce battery consumption. In an alternative method, even if there is no first configuration information for SSB measurement for each frequency, or even if there is no second configuration information for SSB measurement for each frequency, the UE can perform RRC idle mode or RRC inactive mode frequency measurements by being implemented as a synchronized frequency, searching for SSB signals from the start, and deriving parameter values for periodicity, offset, and duration. In another alternative method, the UE can store the reference timing of the cell from which it received the RRCRelease message, and based on the stored timing, perform measurements by applying the first configuration information or the second configuration information to SSB measurement for each frequency.

[0247] A variant of the first embodiment of the efficient RRC idle mode or RRC inactive mode frequency measurement method is as follows.

[0248] In Figure 13In this case, the base station or cell can set the configuration information for RRC idle mode or RRC inactive mode frequency measurement for the UE by using the first frequency measurement configuration information 13-10 in the RRC Release message or the second frequency measurement configuration information 13-20 in the system information.

[0249] If the received RRC Release message contains the first frequency configuration information, the UE can drive the timer by applying the first timer value information of the first frequency configuration information and start the RRC idle mode or RRC inactive mode frequency measurement (i.e., early measurement). In addition, if the first frequency configuration information contains the first area configuration information, the UE can identify the identifier of the cell in which the UE camps through the cell selection or reselection process and can determine whether to perform the early frequency measurement in the RRC idle mode or the RRC inactive mode. If the first frequency configuration information does not contain the first frequency list information to be measured and if the second frequency configuration is broadcast in the system information of the camped cell, the UE can perform the RRC idle mode or RRC inactive mode frequency measurement based on the second frequency configuration information (e.g., the second frequency list information), store the valid measurement results, and when the RRC connection is established later, as Figure 6 described in 6 or 7, report the stored measurement results to the network.

[0250] In a variant of the first embodiment of the method for efficient RRC idle mode or RRC inactive mode frequency measurement, the UE can receive the first frequency configuration information through the RRC Release message, transition to the RRC idle mode or the RRC inactive mode, and perform the frequency measurement. In addition, the UE can receive the second frequency configuration information through the system information of the cell in which the UE camps through the cell selection or reselection process.

[0251] A variant of the first embodiment is characterized in that the UE receives the first frequency configuration information and / or the second frequency configuration information, and is characterized in that when performing frequency measurements in the RRC idle mode or the RRC inactive mode, in the case of receiving the first frequency configuration information and the second frequency configuration information, the UE always gives priority to the first frequency list information over the second frequency list information. However, in the case of receiving the first configuration information for SSB measurement for each frequency and the second configuration information for SSB measurement for each frequency, the second configuration information for SSB measurement for each frequency is given priority. However, if the cell from which the UE receives the system information is the same as the cell from which the UE receives the RRC Release message, and if for a specific frequency in the first frequency list, the UE receives the first configuration information for SSB measurement through the RRC Release message and the second configuration information for SSB measurement through the system information of the same cell, then the UE can apply the first configuration information for SSB measurement to each frequency in the first frequency list. This is because if different types of information are received from the same cell through the RRC Release message and the system information, the UE should give priority to the specific information directly provided by the base station (dedicated to the UE). In the case of some UEs with not much mobility and continuously camping on the same cell, the first configuration information for SSB measurement for each frequency may be more effective for frequency measurements for CA technology or DC technology.

[0252] If the RRC Release message only contains the first frequency list and does not contain the first configuration information for SSB measurement for each frequency, and if the second configuration information for SSB measurement for each frequency included in the first frequency list is broadcast through the system information, the UE can perform frequency measurements by applying the second configuration information for SSB measurement for each frequency to the frequencies in the first frequency list.

[0253] For example, the UE can receive the first frequency configuration information in RRC Release message 13-10 from the first cell, transition to the RRC idle mode or the RRC inactive mode, and then receive the second frequency configuration information in system information 13-20 from the first cell or a new second cell through the cell selection or reselection process.

[0254] The first frequency list of the first frequency configuration information 13-10 may include frequency 1 (13-01), frequency 2 (13-02), frequency 3 (13-03), frequency 4 (13-04), frequency 5 (13-05), and frequency 6 (13-06) as target frequencies to be measured. Among these frequencies, only frequency 1 (13-01), frequency 2 (13-02), frequency 3 (13-03), and frequency 5 (13-05) can be configured with threshold information serving as the standard for measurement and reporting for each frequency, the first configuration information for SSB measurement for each frequency, or the first reporting method for the measurement report for each frequency.

[0255] The second frequency list of the second frequency configuration information 13-20 may include frequency 3 (13-03), frequency 4 (13-04), frequency 5 (13-05), frequency 6 (13-06), frequency 7 (13-07), and frequency 8 (13-08) as target frequencies to be measured. Among these frequencies, only frequency 3 (13-03), frequency 4 (13-04), frequency 7 (13-07), and frequency 8 (13-08) can be configured with threshold information serving as the standard for measurement and reporting for each frequency, the second configuration information for SSB measurement for each frequency, or the second reporting method for the measurement report for each frequency.

[0256] When receiving the first frequency configuration information 13-10 or the second frequency configuration information 13-20, the UE may select the frequencies to be measured and then apply one of the following methods to determine the frequency configuration to be applied to each frequency.

[0257] - Method 1-1-1 (13-51):

[0258] ■ 1> If the UE moves within the first cell from which it has received the RRC Release message and camps on the same first cell again (13-52),

[0259] ◆2> The UE preferentially selects the first frequency configuration information 13-10 for frequency measurement. Therefore, the UE can perform frequency measurement on the frequencies 13-51 (i.e., frequency 1 (13-01), frequency 2 (13-02), frequency 3 (13-03), frequency 4 (13-04), frequency 5 (13-05), and frequency 6 (13-06)) set in the first frequency list by applying the frequency measurement configuration information for each frequency (e.g., threshold information used as a standard for measurement and reporting for each frequency, the first configuration information for SSB measurement for each frequency, or the first reporting method for measurement reporting for each frequency), determine valid frequency measurement results, construct the results to be reported, and store the constructed results. That is, even if the second configuration information for SSB measurement for each frequency corresponding to the first frequency list is broadcast in the system information, the UE can give priority to the information in the RRCRelease message because the RRCRelease message is received from the same cell. Specifically, in method 1-1-1, based on the reference timing of the serving cell where the UE camps through the cell selection or reselection process, the UE can perform frequency measurement by applying the first configuration information (e.g., the periodicity, offset, and / or duration of smtc) to the SSB measurement of the target frequency to be measured (e.g., frequency 4 (13-04)). In an alternative method, the UE can store the reference timing of the cell from which it receives the RRCRelease message and, based on the stored timing, perform measurement by applying the first configuration information or the second configuration information to the SSB measurement of each frequency. If there is neither the first configuration information nor the second configuration information for the SSB measurement of the target frequency to be measured, the UE can refrain from performing the measurement of that frequency to reduce battery consumption. In another alternative method, even if there is no first configuration information for the SSB measurement of each frequency, or even if there is no second configuration information for the SSB measurement of each frequency, the UE can perform RRC idle mode or RRC inactive mode frequency measurement by being implemented as a synchronous frequency, searching for SSB signals from the start, and deriving the parameter values of periodicity, offset, and duration. In yet another alternative method, if there is no first configuration information for the SSB measurement of the target frequency to be measured (e.g., frequency 4 (13-04)), but if the second frequency configuration information received in the system information contains the second configuration information for the SSB measurement of that frequency, the UE can perform frequency measurement by applying the second configuration information (e.g., the periodicity, offset, and / or duration of smtc) for the SSB measurement of that frequency based on the reference timing of the serving cell where the UE camps through the cell selection or reselection process.

[0260] ◆2> If the first frequency configuration information received in the RRC Release message does not contain the configuration information of the first frequency list, the UE may apply Method 2-1 (14-51) described below. Specifically, the UE gives priority to the second frequency configuration information 14-20 to perform frequency measurement. Therefore, the UE can perform frequency measurement only on the frequencies set in the second frequency list (i.e., frequency 3 (14-03), frequency 4 (14-04), frequency 5 (14-05), frequency 6 (14-06), frequency 7 (14-07), and frequency 8 (14-08)) by applying the frequency measurement configuration information of each frequency (e.g., threshold information used as the standard for measurement and reporting of each frequency, the second configuration information for SSB measurement of each frequency, or the second reporting method for measurement reporting of each frequency), determine the valid frequency measurement results, construct the results to be reported, and store the constructed results. Specifically, in Method 2-1, based on the reference timing of the serving cell where the UE camps through the cell selection or reselection process, the UE can perform frequency measurement by applying the second configuration information (e.g., periodicity, offset, and / or duration of smtc) to the SSB measurement of the target frequency to be measured. If there is no second configuration information for SSB measurement for the target frequency to be measured, the UE may not perform the measurement of this frequency to reduce battery consumption. In an alternative method, even when there is no second configuration information for SSB measurement of each frequency, the UE can perform RRC idle mode or RRC inactive mode frequency measurement by being implemented as a synchronized frequency, starting to search for SSB signals, and deriving the parameter values of periodicity, offset, and duration. In another alternative method, Method 2-2 (14-52) may be applied.

[0261] ■1> If the UE moves from the first cell from which it has received the RRC Release message and camps on a new second cell (13-53),

[0262] ◆2>The UE prioritizes the first frequency list of the first frequency configuration information 13-10 for frequency measurement. However, when measuring the frequencies in the first frequency list, it can be characterized by preferring the second configuration information for SSB measurement for each frequency over the first configuration information for SSB measurement for each frequency. Thus, the UE can perform frequency measurement on the frequencies 13-51 (i.e., frequency 1 (13-01), frequency 2 (13-02), frequency 3 (13-03), frequency 4 (13-04), frequency 5 (13-05), and frequency 6 (13-06)) set in the first frequency list by applying the frequency measurement configuration information for each frequency set in the first frequency configuration information 13-10 (e.g., threshold information used as a standard for measurement and reporting for each frequency, the first configuration information for SSB measurement for each frequency, or the first reporting method for measurement reporting for each frequency), determine valid frequency measurement results, construct the results to be reported, and store the constructed results. Specifically, if the first configuration information for SSB measurement for the target frequency corresponding to the first frequency list is received, but if the second configuration information for SSB measurement for that frequency is broadcast in the system information from a new second cell, the UE can prefer the second configuration information for SSB measurement for each frequency broadcast in the system information to perform frequency measurement. That is, in method 1-1-1, based on the reference timing of the serving cell where the UE camps through the cell selection or reselection process, the UE can perform frequency measurement by applying the second configuration information (e.g., periodicity, offset, and / or duration of smtc) to the SSB measurement of the target frequency to be measured (e.g., frequency 4 (13-04)). This is because if the UE moves and camps on a new second cell, the second configuration information for SSB measurement for each frequency broadcast from the new second cell is likely to be more accurate than the first configuration information for SSB measurement for each frequency received from the previous first cell. Additionally, this is because if there is a cell synchronization mismatch in the base station implementation, the system information following the new second cell may not cause problems due to the asynchronous timing between cells. If there is neither the first configuration information nor the second configuration information for SSB measurement for the target frequency to be measured, the UE can refrain from measuring that frequency to reduce battery consumption. In an alternative method, even if there is no first configuration information for SSB measurement for each frequency, or even if there is no second configuration information for SSB measurement for each frequency, the UE can perform RRC idle mode or RRC inactive mode frequency measurement by being implemented as a synchronized frequency, starting to search for SSB signals, and deriving the parameter values of periodicity, offset, and duration.In another alternative method, if the second configuration information for SSB measurement for each frequency is not broadcast in the system information of the target frequency in the first frequency list to be measured, but if the first frequency configuration information received in the RRC Release message contains the first configuration information for SSB measurement for that frequency, then based on the reference timing of the serving cell on which the UE camps through the cell selection or reselection process, the UE can perform frequency measurement by applying the first configuration information (e.g., the periodicity, offset, and / or duration of smtc) to the SSB measurement for that frequency. In yet another alternative method, the UE can store the reference timing of the cell from which it received the RRC Release message, and based on the stored timing, perform the measurement by applying the first configuration information or the second configuration information to the SSB measurement for each frequency. In yet another alternative method, the above Method 1-1 or Method 1-2 can be applied.

[0263] ◆2> If the first frequency configuration information received in the RRC Release message does not contain the configuration information of the first frequency list, the UE can apply Method 2-1 (14-51) described below. Specifically, the UE gives priority to the second frequency configuration information 14-20 for performing frequency measurement. Therefore, the UE can perform frequency measurement only on the frequencies 14-51 (i.e., frequency 3 (14-03), frequency 4 (14-04), frequency 5 (14-05), frequency 6 (14-06), frequency 7 (14-07), and frequency 8 (14-08)) set in the second frequency list by applying the frequency measurement configuration information (e.g., threshold information used as the standard for measurement and reporting for each frequency, the second configuration information for SSB measurement for each frequency, or the second reporting method for measurement reporting for each frequency) set in the second frequency configuration information 14-20, determine the valid frequency measurement results, construct the results to be reported, and store the constructed results. Specifically, in Method 2-1, based on the reference timing of the serving cell on which the UE camps through the cell selection or reselection process, the UE can perform frequency measurement by applying the second configuration information (e.g., the periodicity, offset, and / or duration of smtc) to the SSB measurement for the target frequency to be measured. If there is no second configuration information for SSB measurement for the target frequency to be measured, the UE can refrain from performing the measurement for that frequency to reduce battery consumption. In one alternative method, even when there is no second configuration information for SSB measurement for each frequency, the UE can perform RRC idle mode or RRC inactive mode frequency measurement by being implemented as a synchronous frequency, starting to search for the SSB signal, and deriving the parameter values of the periodicity, offset, and duration. In another alternative method, Method 2-2 (14-52) can be applied.

[0264] Figure 14FIG. is a diagram showing a second embodiment of an effective frequency measurement method in RRC idle mode or RRC inactive mode according to an embodiment of the present disclosure.

[0265] In Figure 14 the base station or cell may set configuration information for RRC idle mode or RRC inactive mode frequency measurement to the UE by using the first frequency measurement configuration information 14-10 in the RRCRelease message or the second frequency measurement configuration information 14-20 in the system information.

[0266] If the received RRCRelease message contains the first frequency configuration information, the UE may drive a timer by applying the first timer value information of the first frequency configuration information and start RRC idle mode or RRC inactive mode frequency measurement (i.e., early measurement). In addition, if the first frequency configuration information contains the first area configuration information, the UE may identify the identifier of the cell on which the UE camps through the cell selection or reselection process and may determine whether to perform early frequency measurement in RRC idle mode or RRC inactive mode. If the first frequency configuration information does not contain the first frequency list information to be measured and if the second frequency configuration is broadcast in the system information of the serving cell, the UE may perform RRC idle mode or RRC inactive mode frequency measurement based on the second frequency configuration information (e.g., the second frequency list information), store the valid measurement results, and when establishing an RRC connection later, as Figure 6 described in 6 or 7, report the stored measurement results to the network.

[0267] In Figure 14 the second embodiment of the efficient RRC idle mode or RRC inactive mode frequency measurement method shown, the UE may receive the first frequency configuration information through the RRCRelease message, transition to the RRC idle mode or RRC inactive mode, and perform frequency measurement. In addition, the UE may receive the second frequency configuration information through the system information of the cell on which the UE camps through the cell selection or reselection process.

[0268] In the second embodiment, the UE may receive the first frequency configuration information and / or the second frequency configuration information, give priority to the second frequency configuration information when performing RRC idle mode or RRC inactive mode frequency measurement, and perform frequency measurement only based on the second frequency configuration information. In addition, with respect to the configuration information not included in the second frequency configuration information, the UE may consider the first frequency configuration information to perform frequency measurement.

[0269] For example, the UE may receive the first frequency configuration information 14-10 in the RRC Release message from the first cell, transition to the RRC idle mode or the RRC inactive mode, and then receive the second frequency configuration information 14-20 in the system information from the first cell or a new second cell through the cell selection or reselection process.

[0270] The first frequency list of the first frequency configuration information 14-10 may include frequency 1 (14-01), frequency 2 (14-02), frequency 3 (14-03), frequency 4 (14-04), frequency 5 (14-05), and frequency 6 (14-06) as the target frequencies to be measured. Among these frequencies, only frequency 1 (14-01), frequency 2 (14-02), frequency 3 (14-03), and frequency 5 (14-05) can be configured with threshold information serving as the standard for measurement and reporting for each frequency, the first configuration information for SSB measurement for each frequency, or the first reporting method for the measurement report for each frequency.

[0271] The second frequency list of the second frequency configuration information 14-20 may include frequency 3 (14-03), frequency 4 (14-04), frequency 5 (14-05), frequency 6 (14-06), frequency 7 (14-07), and frequency 8 (14-08) as the target frequencies to be measured. Among these frequencies, only frequency 3 (14-03), frequency 4 (14-04), frequency 7 (14-07), and frequency 8 (14-08) can be configured with threshold information serving as the standard for measurement and reporting for each frequency, the second configuration information for SSB measurement for each frequency, or the second reporting method for the measurement report for each frequency.

[0272] When receiving the first frequency configuration information 14-10 or the second frequency configuration information 14-20, the UE may select the frequencies to be measured and then apply one of the following methods to determine the frequency configuration to be applied to each frequency.

[0273] -Method 2-1 (14-51): The UE preferentially considers the second frequency configuration information 14-20 to perform frequency measurements. Therefore, the UE can perform frequency measurements only on the frequencies 14-51 (i.e., frequency 3 (14-03), frequency 4 (14-04), frequency 5 (14-05), frequency 6 (14-06), frequency 7 (14-07), and frequency 8 (14-08)) set in the second frequency list by applying the frequency measurement configuration information for each frequency set in the second frequency configuration information 14-20 (e.g., threshold information used as a standard for measurement and reporting for each frequency, second configuration information for SSB measurement for each frequency, or second reporting method for measurement reporting for each frequency), determine valid frequency measurement results, construct the results to be reported, and store the constructed results. Specifically, in Method 2-1, based on the reference timing of the serving cell on which the UE camps through the cell selection or reselection process, the UE can perform frequency measurements by applying the second configuration information (e.g., periodicity, offset, and / or duration of smtc) for SSB measurement for each frequency. If there is no second configuration information for SSB measurement of the target frequency to be measured, the UE may not perform the measurement of that frequency to reduce battery consumption. In an alternative method, even when there is no second configuration information (e.g., periodicity, offset, and / or duration of smtc) for SSB measurement of that frequency, the UE can perform RRC idle mode or RRC inactive mode frequency measurements by being implemented as a synchronized frequency, starting to search for SSB signals, and deriving the parameter values of periodicity, offset, and duration.

[0274] - Method 2-2 (14-52): The UE preferentially considers the second frequency configuration information 14-20 to perform frequency measurements. Thus, the UE can perform frequency measurements only on the frequencies 14-52 (i.e., frequency 3 (14-03), frequency 4 (14-04), frequency 5 (14-05), frequency 6 (14-06), frequency 7 (14-07), and frequency 8 (14-08)) set in the second frequency list by applying the frequency measurement configuration information for each frequency set in the second frequency configuration information 14-20 (e.g., threshold information used as a standard for measurement and reporting for each frequency, second configuration information for SSB measurement for each frequency, or second reporting method for measurement reporting for each frequency), determine valid frequency measurement results, construct the results to be reported, and store the constructed results. Specifically, in Method 2-2, based on the reference timing of the serving cell on which the UE camps through the cell selection or reselection process, the UE can perform frequency measurements by applying the second configuration information (e.g., periodicity, offset, and / or duration of smtc) for SSB measurement for each frequency. If there is no second configuration information for SSB measurement for the target frequency to be measured (e.g., frequency 5 (14-05)), but if the first frequency configuration information received in the RRC Release message contains the first configuration information for SSB measurement for that frequency, then based on the reference timing of the serving cell on which the UE camps through the cell selection or reselection process, the UE can perform frequency measurements by applying the first configuration information (e.g., periodicity, offset, and / or duration of smtc) for SSB measurement for that frequency (e.g., frequency 5 (14-05)). If there is neither the first configuration information nor the second configuration information for SSB measurement for the target frequency to be measured, the UE may not perform the measurement for that frequency to reduce battery consumption. In an alternative method, even if there is no first configuration information for SSB measurement for each frequency, or even if there is no second configuration information for SSB measurement for each frequency, the UE can perform RRC idle mode or RRC inactive mode frequency measurements by being implemented as a synchronous frequency, starting to search for SSB signals, and deriving parameter values for periodicity, offset, and duration.

[0275] Figure 15 is a diagram showing a third embodiment of an effective frequency measurement method in the RRC idle mode or RRC inactive mode according to an embodiment of the present disclosure.

[0276] In Figure 15 the base station or cell can set the configuration information for RRC idle mode or RRC inactive mode frequency measurement for the UE by using the first frequency measurement configuration information 15-10 in the RRC Release message or the second frequency measurement configuration information 15-20 in the system information.

[0277] If the received RRCRelease message includes first frequency configuration information, the UE may drive a timer by applying the first timer value information of the first frequency configuration information and start RRC idle mode or RRC inactive mode frequency measurements (i.e., early measurements). In addition, if the first frequency configuration information includes first area configuration information, the UE may identify the identifier of the cell on which the UE camps through the cell selection or reselection process and may determine whether to perform early frequency measurements in RRC idle mode or RRC inactive mode. If the first frequency configuration information does not include the first frequency list information to be measured and if a second frequency configuration is broadcast in the system information of the camped cell, the UE may perform RRC idle mode or RRC inactive mode frequency measurements based on the second frequency configuration information (e.g., the second frequency list information), store valid measurement results, and when an RRC connection is established later, as Figure 6 described in 7 or 7, report the stored measurement results to the network.

[0278] In Figure 15 the third embodiment of the efficient RRC idle mode or RRC inactive mode frequency measurement method shown, the UE may receive the first frequency configuration information through the RRCRelease message, transition to the RRC idle mode or RRC inactive mode, and perform frequency measurements. In addition, the UE may receive the second frequency configuration information through the system information of the cell on which the UE camps through the cell selection or reselection process.

[0279] The third embodiment is characterized in that the UE receives the first frequency configuration information and / or the second frequency configuration information, compares the first frequency configuration information and the second frequency configuration information when performing RRC idle mode or RRC inactive mode frequency measurements, and performs frequency measurements on the frequencies corresponding to the intersection of the first frequency list and the second frequency list based on the first frequency configuration information or the second frequency configuration information. In addition, the UE may perform frequency measurements considering the second frequency configuration information regarding the configuration information not included in the first frequency configuration information and may perform frequency measurements considering the first frequency configuration information regarding the configuration information not included in the second frequency configuration information.

[0280] For example, the UE may receive the first frequency configuration information 15-10 in the RRCRelease message from the first cell, transition to the RRC idle mode or RRC inactive mode, and then receive the second frequency configuration information 15-20 in the system information from the first cell or a new second cell through the cell selection or reselection process.

[0281] The first frequency list of the first frequency configuration information 15-10 may include frequency 1 (15-01), frequency 2 (15-02), frequency 3 (15-03), frequency 4 (15-04), frequency 5 (15-05), and frequency 6 (15-06) as target frequencies to be measured. Among these frequencies, only frequency 1 (15-01), frequency 2 (15-02), frequency 3 (15-03), and frequency 5 (15-05) can be configured with threshold information serving as the standard for measurement and reporting for each frequency, the first configuration information for SSB measurement for each frequency, or the first reporting method for measurement reports for each frequency.

[0282] The second frequency list of the second frequency configuration information 15-20 may include frequency 3 (15-03), frequency 4 (15-04), frequency 5 (15-05), frequency 6 (15-06), frequency 7 (15-07), and frequency 8 (15-08) as target frequencies to be measured. Among these frequencies, only frequency 3 (15-03), frequency 4 (15-04), frequency 7 (15-07), and frequency 8 (15-08) can be configured with threshold information serving as the standard for measurement and reporting for each frequency, the second configuration information for SSB measurement for each frequency, or the second reporting method for measurement reports for each frequency.

[0283] When receiving the first frequency configuration information 15-10 or the second frequency configuration information 15-20, the UE may select the frequencies to be measured and then apply one of the following methods to determine the frequency configuration to be applied to each frequency.

[0284] - Method 3-1 (15-51): When receiving the first frequency configuration information 15-10 or the second frequency configuration information 15-20, the UE compares the first frequency list information of the first frequency configuration information and the second frequency list information of the second frequency configuration information, selects the frequencies corresponding to the intersection, and performs frequency measurements on the selected frequencies. Thus, the UE can perform frequency measurements only on the frequencies 15-30 (i.e., frequency 3 (15-03), frequency 4 (15-04), frequency 5 (15-05), and frequency 6 (15-06)) corresponding to the intersection between the first and second frequency lists by applying the frequency measurement configuration information (e.g., threshold information used as the standard for measurement and reporting for each frequency, the first configuration information for SSB measurement for each frequency, or the first reporting method for measurement reporting for each frequency) set in the first frequency configuration information, determine valid frequency measurement results, construct the results to be reported, and store the constructed results. Specifically, in Method 3-1, based on the reference timing of the serving cell on which the UE camps through the cell selection or reselection process, the UE can perform frequency measurements by applying the first configuration information (e.g., periodicity, offset, and / or duration of smtc) for SSB measurement for each frequency. If there is no first configuration information for SSB measurement of the target frequency to be measured, the UE may not perform the measurement of that frequency to reduce battery consumption. In an alternative method, even when there is no first configuration information (e.g., periodicity, offset, and / or duration of smtc) for SSB measurement of the frequency, the UE can perform RRC idle mode or RRC inactive mode frequency measurements by being implemented as a synchronized frequency, starting to search for SSB signals, and deriving the parameter values of periodicity, offset, and duration. In another alternative method, the UE can store the reference timing of the cell from which it receives the RRC Release message, and based on the stored timing, perform measurements by applying the first configuration information to SSB measurement for each frequency. In this Method 3-1, the UE performs frequency measurements only based on the first frequency configuration information, so that it is not necessary to read a large amount of system information, thereby reducing the battery consumption of the UE.

[0285] - Method 3-2 (15-52): When the first frequency configuration information 15-10 or the second frequency configuration information 15-20 is received, the UE compares the first frequency list information of the first frequency configuration information and the second frequency list information of the second frequency configuration information, selects the frequencies corresponding to the intersection, and performs frequency measurements on the selected frequencies. Accordingly, the UE can perform frequency measurements only on the frequencies 15-30 (i.e., frequency 3 (15-03), frequency 4 (15-04), frequency 5 (15-05), and frequency 6 (15-06)) corresponding to the intersection between the first and second frequency lists by applying the frequency measurement configuration information (e.g., threshold information used as a standard for measurement and reporting for each frequency, the first configuration information for SSB measurement for each frequency, or the first reporting method for measurement reporting for each frequency) set in the first frequency configuration information, determine valid frequency measurement results, construct the results to be reported, and store the constructed results. Specifically, in Method 3-2, based on the reference timing of the serving cell on which the UE camps through the cell selection or reselection process, the UE can perform frequency measurements by applying the first configuration information (e.g., periodicity, offset, and / or duration of smtc) for SSB measurement for each frequency. If there is no first configuration information for SSB measurement for the target frequency to be measured (e.g., frequency 4 (15-04)), but if the second frequency configuration information received in the system information contains the second configuration information for SSB measurement for that frequency, then based on the reference timing of the serving cell on which the UE camps through the cell selection or reselection process, the UE can perform frequency measurements by applying the second configuration information (e.g., periodicity, offset, and / or duration of smtc) for SSB measurement for that frequency (e.g., frequency 4 (15-04)). If there is neither the first configuration information nor the second configuration information for SSB measurement for the target frequency to be measured, the UE may not perform the measurement for that frequency to reduce battery consumption. In an alternative method, even if there is no first configuration information for SSB measurement for each frequency, or even if there is no second configuration information for SSB measurement for each frequency, the UE can perform RRC idle mode or RRC inactive mode frequency measurements by being implemented as a synchronized frequency, starting to search for SSB signals, and deriving the parameter values of periodicity, offset, and duration.

[0286] - Method 3-3 (15-53): When receiving the first frequency configuration information 15-10 or the second frequency configuration information 15-20, the UE compares the first frequency list information of the first frequency configuration information and the second frequency list information of the second frequency configuration information, selects the frequencies corresponding to the intersection, and performs frequency measurements on the selected frequencies. Thus, the UE can perform frequency measurements only on the frequencies 15-30 corresponding to the intersection between the first and second frequency lists (i.e., frequency 3 (15-03), frequency 4 (15-04), frequency 5 (15-05), and frequency 6 (15-06)) by applying the frequency measurement configuration information for each frequency set in the second frequency configuration information (e.g., threshold information used as a standard for measurement and reporting for each frequency, the second configuration information for SSB measurement for each frequency, or the second reporting method for measurement reporting for each frequency), determine valid frequency measurement results, construct the results to be reported, and store the constructed results. Specifically, in Method 3-3, based on the reference timing of the serving cell on which the UE camps through the cell selection or reselection process, the UE can perform frequency measurements by applying the second configuration information (e.g., periodicity, offset, and / or duration of smtc) for SSB measurement for each frequency. If there is no second configuration information for SSB measurement of the target frequency to be measured, the UE may not perform the measurement of that frequency to reduce battery consumption. In an alternative method, even when there is no second configuration information (e.g., periodicity, offset, and / or duration of smtc) for SSB measurement of the frequency, the UE can perform RRC idle mode or RRC inactive mode frequency measurements by being implemented as a synchronized frequency, starting to search for SSB signals, and deriving the parameter values of periodicity, offset, and duration.

[0287] - Method 3-4 (15-54): When receiving the first frequency configuration information 15-10 or the second frequency configuration information 15-20, the UE compares the first frequency list information of the first frequency configuration information and the second frequency list information of the second frequency configuration information, selects the frequencies corresponding to the intersection, and performs frequency measurements on the selected frequencies. Therefore, the UE can perform frequency measurements only on the frequencies 15-30 (i.e., frequency 3 (15-03), frequency 4 (15-04), frequency 5 (15-05), and frequency 6 (15-06)) corresponding to the intersection between the first and second frequency lists by applying the frequency measurement configuration information (e.g., threshold information used as the standard for measurement and reporting for each frequency, the second configuration information for SSB measurement for each frequency, or the second reporting method for measurement reporting for each frequency) set in the second frequency configuration information, determine valid frequency measurement results, construct the results to be reported, and store the constructed results. Specifically, in Method 3-4, based on the reference timing of the serving cell on which the UE camps through the cell selection or reselection process, the UE can perform frequency measurements by applying the second configuration information (e.g., the periodicity, offset, and / or duration of smtc) for SSB measurement for each frequency. If there is no second configuration information for SSB measurement for the target frequency to be measured (e.g., frequency 5 (15-05)), but if the first frequency configuration information received in the RRCRelease message contains the first configuration information for SSB measurement for this frequency, then based on the reference timing of the serving cell on which the UE camps through the cell selection or reselection process, the UE can perform frequency measurements by applying the first configuration information (e.g., the periodicity, offset, and / or duration of smtc) for SSB measurement for this frequency (e.g., frequency 5 (15-05)). If there is neither the first configuration information nor the second configuration information for SSB measurement for the target frequency to be measured, the UE may not perform the measurement for this frequency to reduce battery consumption. In an alternative method, even if there is no first configuration information for SSB measurement for each frequency, or even if there is no second configuration information for SSB measurement for each frequency, the UE can perform RRC idle mode or RRC inactive mode frequency measurements by being implemented as a synchronized frequency, starting to search for SSB signals, and deriving the parameter values of the periodicity, offset, and duration.

[0288] Figure 16 It is a diagram showing a fourth embodiment of an effective frequency measurement method in the RRC idle mode or RRC inactive mode according to an embodiment of the present disclosure.

[0289] In Figure 16In this case, the base station or cell can set the configuration information for RRC idle mode or RRC inactive mode frequency measurement for the UE by using the first frequency measurement configuration information 16-10 in the RRCRelease message or the second frequency measurement configuration information 16-20 in the system information.

[0290] If the received RRCRelease message contains the first frequency configuration information, the UE can drive the timer by applying the first timer value information of the first frequency configuration information and start the RRC idle mode or RRC inactive mode frequency measurement (i.e., early measurement). In addition, if the first frequency configuration information contains the first area configuration information, the UE can identify the identifier of the cell on which the UE camps through the cell selection or reselection process and can determine whether to perform the early frequency measurement in the RRC idle mode or the RRC inactive mode. If the first frequency configuration information does not contain the first frequency list information to be measured and if the second frequency configuration is broadcast in the system information of the camped cell, the UE can perform the RRC idle mode or RRC inactive mode frequency measurement based on the second frequency configuration information (e.g., the second frequency list information), store the valid measurement results, and when establishing an RRC connection later, as Figure 6 described in 6 or 7, report the stored measurement results to the network.

[0291] In Figure 16 the fourth embodiment of the efficient RRC idle mode or RRC inactive mode frequency measurement method shown, the UE can receive the first frequency configuration information through the RRCRelease message, transition to the RRC idle mode or RRC inactive mode, and perform the frequency measurement. In addition, the UE can receive the second frequency configuration information through the system information of the cell on which the UE camps through the cell selection or reselection process.

[0292] The fourth embodiment is characterized in that the UE receives the first frequency configuration information and / or the second frequency configuration information, compares the first frequency configuration information and the second frequency configuration information when performing the RRC idle mode or RRC inactive mode frequency measurement, and performs the frequency measurement on the frequencies corresponding to the union of the first frequency list and the second frequency list based on the first frequency configuration information or the second frequency configuration information. In addition, the UE can perform the frequency measurement considering the second frequency configuration information on the configuration information not included in the first frequency configuration information and can perform the frequency measurement considering the first frequency configuration information on the configuration information not included in the second frequency configuration information.

[0293] For example, the UE may receive the first frequency configuration information 16-10 in the RRC Release message from the first cell, transition to the RRC idle mode or the RRC inactive mode, and then receive the second frequency configuration information 16-20 in the system information from the first cell or a new second cell through the cell selection or reselection process.

[0294] The first frequency list of the first frequency configuration information 16-10 may include Frequency 1 (16-01), Frequency 2 (16-02), Frequency 3 (16-03), Frequency 4 (16-04), Frequency 5 (16-05), and Frequency 6 (16-06) as the target frequencies to be measured. Among these frequencies, only Frequency 1 (16-01), Frequency 2 (16-02), Frequency 3 (16-03), and Frequency 5 (16-05) can be configured with threshold information serving as the standard for measurement and reporting for each frequency, the first configuration information of the SSB measurement for each frequency, or the first reporting method of the measurement report for each frequency.

[0295] The second frequency list of the second frequency configuration information 16-20 may include Frequency 3 (16-03), Frequency 4 (16-04), Frequency 5 (16-05), Frequency 6 (16-06), Frequency 7 (16-07), and Frequency 8 (16-08) as the target frequencies to be measured. Among these frequencies, only Frequency 3 (16-03), Frequency 4 (16-04), Frequency 7 (16-07), and Frequency 8 (16-08) can be configured with threshold information serving as the standard for measurement and reporting for each frequency, the second configuration information of the SSB measurement for each frequency, or the second reporting method of the measurement report for each frequency.

[0296] When receiving the first frequency configuration information 16-10 or the second frequency configuration information 16-20, the UE may select the frequencies to be measured and then apply one of the following methods to determine the frequency configuration to be applied to each frequency.

[0297] - Method 4-1 (16-51): When receiving the first frequency configuration information 16-10 or the second frequency configuration information 16-20, the UE compares the first frequency list information of the first frequency configuration information and the second frequency list information of the second frequency configuration information, selects the frequencies corresponding to the union, and performs frequency measurements on the selected frequencies. Thus, the UE performs frequency measurements only on the frequencies 16-10, 16-20, and 16-30 (i.e., frequency 1 (16-01), frequency 2 (16-02), frequency 3 (16-03), frequency 4 (16-04), frequency 5 (16-05), frequency 6 (16-06), frequency 7 (16-07), and frequency 8 (16-08)) corresponding to the union between the first and second frequency lists by applying the frequency measurement configuration information of each frequency set in the first or second frequency configuration information (e.g., threshold information used as a standard for measurement and reporting of each frequency, the first or second configuration information for SSB measurement of each frequency, or the first or second reporting method for measurement reporting of each frequency), determines valid frequency measurement results, constructs the results to be reported, and stores the constructed results. Specifically, in Method 4-1, based on the reference timing of the serving cell on which the UE camps through the cell selection or reselection process, the UE can perform frequency measurements by applying the first configuration information for SSB measurement (e.g., periodicity, offset, and / or duration of smtc) to each frequency of the first frequency list or by applying the second configuration information for SSB measurement to each frequency of the second frequency list. In Method 4-1, the UE can give priority to the first frequency configuration information for the frequencies corresponding to the intersection between the first and second frequency lists. If there is both the first frequency configuration information and the second frequency configuration information regarding the target frequency to be measured (e.g., frequency 3 (16-03)), the UE can give priority to the first frequency configuration information. If there is no first configuration information for SSB measurement of the target frequency to be measured in the first frequency list, or if there is no second configuration information for SSB measurement of the target frequency to be measured in the second frequency list, the UE can refrain from performing frequency measurements to reduce battery consumption. In an alternative method, even when there is no first configuration information for SSB measurement of the target frequency in the first frequency list, or even when there is no second configuration information for SSB measurement of the target frequency in the second frequency list, the UE can perform RRC idle mode or RRC inactive mode frequency measurements by being implemented as a synchronized frequency, starting to search for SSB signals, and deriving parameter values of periodicity, offset, and duration.

[0298] -Method 4-2 (16-52): When the first frequency configuration information 16-10 or the second frequency configuration information 16-20 is received, the UE compares the first frequency list information of the first frequency configuration information and the second frequency list information of the second frequency configuration information, selects the frequencies corresponding to the union, and performs frequency measurements on the selected frequencies. Therefore, the UE performs frequency measurements only on the frequencies 16-10, 16-20, and 16-30 (i.e., frequency 1 (16-01), frequency 2 (16-02), frequency 3 (16-03), frequency 4 (16-04), frequency 5 (16-05), frequency 6 (16-06), frequency 7 (16-07), and frequency 8 (16-08)) corresponding to the union between the first and second frequency lists by applying the frequency measurement configuration information (e.g., threshold information used as the standard for measurement and reporting for each frequency, the first or second configuration information for SSB measurement for each frequency, or the first or second reporting method for measurement reporting for each frequency) set in the first or second frequency configuration information, determines valid frequency measurement results, constructs the results to be reported, and stores the constructed results. Specifically, in Method 4-2, based on the reference timing of the serving cell on which the UE camps through the cell selection or reselection process, the UE can perform frequency measurements by applying the first configuration information for SSB measurement (e.g., the periodicity, offset, and / or duration of smtc) to each frequency of the first frequency list or applying the second configuration information for SSB measurement to each frequency of the second frequency list. In Method 4-2, the UE can give priority to the first frequency configuration information for the frequencies corresponding to the intersection between the first and second frequency lists. If there is both the first frequency configuration information and the second frequency configuration information regarding the target frequency to be measured (e.g., frequency 3 (16-03)), the UE can give priority to the first frequency configuration information. If there is no first configuration information for SSB measurement for the target frequency to be measured (e.g., frequency 4 (16-04)), but if the second frequency configuration information received in the system information contains the second configuration information for SSB measurement for this frequency, based on the reference timing of the serving cell on which the UE camps through the cell selection or reselection process, the UE can perform frequency measurements by applying the second configuration information for SSB measurement (e.g., the periodicity, offset, and / or duration of smtc) for this frequency (e.g., frequency 4 (16-04)).In addition, if there is no second configuration information for SSB measurement for the target frequency to be measured (e.g., frequency 5 (16 - 05)), but if the first frequency configuration information received in the RRC Release message includes the first configuration information for SSB measurement for this frequency, then based on the reference timing of the serving cell on which the UE camps through the cell selection or reselection process, the UE can perform frequency measurement by applying the first configuration information (e.g., periodicity, offset, and / or duration of smtc) for SSB measurement for this frequency (e.g., frequency 5 (16 - 05)). If there is neither the first configuration information nor the second configuration information for SSB measurement for the target frequency to be measured, the UE may not perform the measurement of this frequency to reduce battery consumption. In an alternative method, even if there is no first configuration information for SSB measurement for each frequency, or even if there is no second configuration information for SSB measurement for each frequency, the UE can perform RRC idle mode or RRC inactive mode frequency measurement by being implemented as a synchronous frequency, starting to search for SSB signals, and deriving the parameter values of periodicity, offset, and duration.

[0299] -Method 4-3 (16-53): When receiving the first frequency configuration information 16-10 or the second frequency configuration information 16-20, the UE compares the first frequency list information of the first frequency configuration information and the second frequency list information of the second frequency configuration information, selects the frequencies corresponding to the union, and performs frequency measurements on the selected frequencies. Therefore, the UE performs frequency measurements only on the frequencies 16-10, 16-20, and 16-30 (i.e., frequency 1 (16-01), frequency 2 (16-02), frequency 3 (16-03), frequency 4 (16-04), frequency 5 (16-05), frequency 6 (16-06), frequency 7 (16-07), and frequency 8 (16-08)) corresponding to the union between the first and second frequency lists by applying the frequency measurement configuration information (e.g., threshold information used as a standard for measurement and reporting for each frequency, the first or second configuration information for SSB measurement for each frequency, or the first or second reporting method for measurement reporting for each frequency) set in the first or second frequency configuration information, determines valid frequency measurement results, constructs the results to be reported, and stores the constructed results. Specifically, in Method 4-3, based on the reference timing of the serving cell on which the UE camps through the cell selection or reselection process, the UE can perform frequency measurements by applying the first configuration information for SSB measurement (e.g., periodicity, offset, and / or duration of smtc) to each frequency of the first frequency list or applying the second configuration information for SSB measurement to each frequency of the second frequency list. In Method 4-3, the UE can give priority to the second frequency configuration information for the frequencies corresponding to the intersection between the first and second frequency lists. If there is both the first frequency configuration information and the second frequency configuration information regarding the target frequency to be measured (e.g., frequency 3 (16-03)), the UE can give priority to the second frequency configuration information. If there is no first configuration information for SSB measurement of the target frequency to be measured in the first frequency list, or if there is no second configuration information for SSB measurement of the target frequency to be measured in the second frequency list, the UE may not perform frequency measurements to reduce battery consumption. In an alternative method, even when there is no first configuration information for SSB measurement of the target frequency in the first frequency list, or even when there is no second configuration information for SSB measurement of the target frequency in the second frequency list, the UE can perform RRC idle mode or RRC inactive mode frequency measurements by being implemented as a synchronized frequency, starting to search for SSB signals, and deriving parameter values of periodicity, offset, and duration.

[0300] - Method 4-4 (16-54): When receiving the first frequency configuration information 16-10 or the second frequency configuration information 16-20, the UE compares the first frequency list information of the first frequency configuration information and the second frequency list information of the second frequency configuration information, selects the frequencies corresponding to the union, and performs frequency measurements on the selected frequencies. Therefore, the UE performs frequency measurements only on the frequencies 16-10, 16-20, and 16-30 (i.e., frequency 1 (16-01), frequency 2 (16-02), frequency 3 (16-03), frequency 4 (16-04), frequency 5 (16-05), frequency 6 (16-06), frequency 7 (16-07), and frequency 8 (16-08)) corresponding to the union between the first and second frequency lists by applying the frequency measurement configuration information for each frequency set in the first or second frequency configuration information (e.g., threshold information used as the standard for measurement and reporting for each frequency, the first or second configuration information for SSB measurement for each frequency, or the first or second reporting method for measurement reporting for each frequency), determines valid frequency measurement results, constructs the results to be reported, and stores the constructed results. Specifically, in Method 4-4, based on the reference timing of the serving cell on which the UE camps through the cell selection or reselection process, the UE can perform frequency measurements by applying the first configuration information for SSB measurement (e.g., the periodicity, offset, and / or duration of smtc) to each frequency in the first frequency list or applying the second configuration information for SSB measurement to each frequency in the second frequency list. In Method 4-4, the UE can give priority to the second frequency configuration information for the frequencies corresponding to the intersection between the first and second frequency lists. If there is both the first frequency configuration information and the second frequency configuration information regarding the target frequency to be measured (e.g., frequency 3 (16-03)), the UE can give priority to the second frequency configuration information. If there is no first configuration information for SSB measurement for the target frequency to be measured (e.g., frequency 4 (16-04)), but if the second frequency configuration information received in the system information contains the second configuration information for SSB measurement for this frequency, based on the reference timing of the serving cell on which the UE camps through the cell selection or reselection process, the UE can perform frequency measurements by applying the second configuration information for SSB measurement (e.g., the periodicity, offset, and / or duration of smtc) for this frequency (e.g., frequency 4 (16-04)).In addition, if there is no second configuration information for SSB measurement for the target frequency to be measured (e.g., frequency 5 (16 - 05)), but if the first frequency configuration information received in the RRC Release message includes the first configuration information for SSB measurement for this frequency, then based on the reference timing of the serving cell on which the UE camps through the cell selection or reselection process, the UE can perform frequency measurement by applying the first configuration information (e.g., periodicity, offset, and / or duration of smtc) for SSB measurement for this frequency (e.g., frequency 5 (16 - 05)). If there is neither first configuration information nor second configuration information for SSB measurement for the target frequency to be measured, the UE may not perform the measurement of this frequency to reduce battery consumption. In an alternative method, even if there is no first configuration information for SSB measurement for each frequency, or even if there is no second configuration information for SSB measurement for each frequency, the UE can perform RRC idle mode or RRC inactive mode frequency measurement by being implemented as a synchronized frequency, starting to search for SSB signals, and deriving parameter values of periodicity, offset, and duration.

[0301] Meanwhile, each of the above first, second, third, and fourth embodiments can also be applied to other cases where the base station or network sets the configuration information for RRC idle mode or RRC inactive mode frequency measurement by only using the first frequency configuration information of the RRC Release message. Similarly, each of the above first, second, third, and fourth embodiments can also be applied to other cases where the base station or network sets the configuration information for RRC idle mode or RRC inactive mode frequency measurement by only using the second frequency configuration information of the system information.

[0302] Figure 17 It is a diagram showing a method for a terminal to perform frequency measurement in RRC idle mode or RRC inactive mode in a network where the terminal is not synchronized between different frequencies or cells according to an embodiment of the present disclosure.

[0303] In Figure 17 , a UE that transmits / receives data in RRC connected mode in the current cell 17 - 01 (the first cell) can receive an RRC Release message from the base station of the current cell 17 - 01, transition to RRC idle mode or RRC inactive mode, and move while performing the cell selection or reselection process. The RRC Release message may include the first frequency configuration information. In addition, the RRC idle mode or RRC inactive mode UE can camp on a suitable cell through the cell selection or reselection process and obtain the system information. The UE can receive the second frequency configuration information in the system information.

[0304] If the received RRC Release message contains the first frequency configuration information, the UE may drive a timer by applying the first timer value information of the first frequency configuration information and start early frequency measurements in the RRC idle mode or the RRC inactive mode. In addition, if the first frequency configuration information contains the first area configuration information, the UE may identify the identifier of the serving cell and determine whether to perform early frequency measurements in the RRC idle mode or the RRC inactive mode.

[0305] If the UE is in the serving area of the first cell 17-01, the UE may perform early frequency measurements in the RRC idle mode or the RRC inactive mode based on the first frequency configuration information received in the RRC Release message or the second frequency configuration information broadcast as system information by the first cell 17-01. Specifically, according to the first, second, third, or fourth embodiment described above, the UE may perform early frequency measurements in the RRC idle mode or the RRC inactive mode.

[0306] If the UE moves from the first cell 17-01 to the serving area of the second cell 17-02 and camps on the second cell 17-02, the UE may perform RRC idle mode or RRC inactive mode frequency measurements based on the first frequency configuration information received in the RRC Release message or the second frequency configuration information broadcast as system information by the second cell 17-02. Specifically, according to the first, second, third, or fourth embodiment described above, the UE may perform early frequency measurements in the RRC idle mode or the RRC inactive mode.

[0307] A method is described below for the UE to determine a reference timing when performing frequency measurements based on the first frequency configuration information that has been set by the base station or the network through an RRC message (e.g., an RRC Release message or an RRC Reconfiguration message). The reference timing determination method to be described below can be applied to each of the first, second, third, and fourth embodiments above.

[0308] - Reference Timing Determination Method 1: In Reference Timing Determination Method 1, the network may assume that all frequencies of the network are managed to be synchronized, or assume that synchronization information is broadcast through the system information of each cell. Therefore, the base station may set the first frequency configuration information in the RRC message to the UE, and the UE may determine the reference timing for frequency measurements in the RRC idle mode or the RRC inactive mode based on the reference timing (e.g., SFN 0) of the cell on which the UE camps or synchronizes through the cell selection or reselection process, and may apply the SSB configuration information for each frequency to perform RRC idle mode or RRC inactive mode frequency measurements.

[0309] -Reference Timing Determination Method 2: In Reference Timing Determination Method 2, the network does not assume that all frequencies of the network are managed to be synchronized. Therefore, the base station can assume the current cell as the reference timing, and thus set the first frequency configuration information in the RRC message to the UE. Then, the UE can store the cell reference timing (e.g., SFN 0) of the first frequency configuration information received through the RRC message, determine the reference timing for frequency measurement in the RRC idle mode or RRC inactive mode based on the stored reference timing, and apply the SSB configuration information for each frequency to perform the RRC idle mode or RRC inactive mode frequency measurement.

[0310] -Reference Timing Determination Method 3: In Reference Timing Determination Method 3, the network does not assume that all frequencies of the network are managed to be synchronized. Therefore, the base station can assume the current cell or the cell indicated in the first area configuration information as the reference timing, and thus set the first frequency configuration information in the RRC message to the UE. Then, the UE can perform the RRC idle mode or RRC inactive mode frequency measurement only when the cell in which the UE camps through the cell selection or reselection process is the cell that sends the first frequency configuration information through the RRC message or the cell indicated in the first area information of the first frequency configuration information. In other cases, the UE can stop the frequency measurement. Therefore, the UE can store the cell reference timing (e.g., SFN 0) of the first frequency configuration information received through the RRC message, and based on the stored reference timing, determine the reference timing for frequency measurement, or alternatively, based on the reference timing of the camped cell, determine the reference timing for frequency measurement. Then, based on the reference timing, the UE can apply the SSB configuration information for each frequency to perform the RRC idle mode or RRC inactive mode frequency measurement.

[0311] -Reference Timing Determination Method 4: In Reference Timing Determination Method 4, the network does not assume that all frequencies of the network are managed to be synchronized. Therefore, the base station can set only the frequencies synchronized throughout the network to the UE in the first frequency configuration information through the RRC message (assuming that the frequencies included in the first frequency list are synchronized throughout the network). Therefore, for each frequency in the first frequency list set in the first frequency configuration information, the UE can synchronize with any cell of the corresponding frequency, determine the reference timing based on the reference timing of the synchronized cell, and apply the SSB configuration information for each frequency to perform the RRC idle mode or RRC inactive mode frequency measurement.

[0312] -Reference Timing Determination Method 5: In Reference Timing Determination Method 5, the network does not assume that all frequencies of the network are managed to be synchronized. Therefore, the base station can set, via an RRC message, only the frequencies that are synchronized across the network in the first frequency configuration information to the UE (assuming that the frequencies included in the first frequency list are synchronized across the network). Thus, for a specific frequency in the first frequency list set in the first frequency configuration information, the UE can synchronize with any cell of any frequency in the first frequency list, determine the reference timing based on the reference timing of the synchronized cell, and apply the SSB configuration information for each frequency to perform RRC idle mode or RRC inactive mode frequency measurements.

[0313] -Reference Timing Determination Method 6: In Reference Timing Determination Method 6, the network does not assume that all frequencies of the network are managed to be synchronized. Therefore, the base station can set, via an RRC message, the reference frequency, cell, or area that is synchronized across the network (assuming that the frequencies included in the separate reference list are synchronized across the network) to the UE as a separate reference list in the first frequency configuration information. Thus, for a certain frequency in the first frequency list set in the first frequency configuration information, the UE can synchronize with any cell of any frequency in the separate reference frequency list, determine the reference timing based on the reference timing of the synchronized cell, and apply the SSB configuration information for each frequency to perform RRC idle mode or RRC inactive mode frequency measurements.

[0314] Based on the second frequency configuration information broadcast in the system information, when performing cell selection or reselection procedures, measuring neighboring cells, or performing RRC idle mode or RRC inactive mode frequency measurements, the above reference timing determination methods 1, 2, 3, 4, 5, and 6 can be applied.

[0315] In addition, the following describes the first UE operation for performing frequency measurements in different ways according to which RRC message is used to set the frequency measurement configuration information to the UE.

[0316] -When the received RRC message is an RRC Release message, the RRC connected mode UE transitions to the RRC idle mode or the RRC inactive mode. Then, if the RRC message contains frequency measurement configuration information (e.g., the first frequency measurement configuration information for the RRC idle mode or the RRC inactive mode), the UE applies the SSB configuration information or the smtc configuration information to the frequencies to be measured based on the serving cell on which the UE camps through the cell selection or reselection procedure, thereby performing frequency measurements.

[0317] - When the received RRC message is an RRCReconfiguration message, the RRC connected mode UE performs frequency measurement in the RRC connected mode. If the RRC message contains frequency measurement configuration information (e.g., the first frequency measurement configuration information for the RRC connected mode), the UE applies the SSB configuration information or smtc configuration information to the frequency to be measured based on the currently connected PCell, thereby performing the frequency measurement.

[0318] In addition, the following describes a second UE operation for performing frequency measurement in different ways according to which RRC message is used to set the frequency measurement configuration information for the UE.

[0319] - When the received RRC message is an RRCRelease message, the RRC connected mode UE transitions to the RRC idle mode or the RRC inactive mode. Then, if the RRC message contains frequency measurement configuration information (e.g., the first frequency measurement configuration information for the RRC idle mode or the RRC inactive mode), the UE applies the first, second, third, or fourth embodiment described above, thereby performing the frequency measurement.

[0320] - When the received RRC message is an RRCReconfiguration message, the RRC connected mode UE performs frequency measurement in the RRC connected mode. If the RRC message contains frequency measurement configuration information (e.g., the first frequency measurement configuration information for the RRC connected mode), the UE applies the SSB configuration information or smtc configuration information to the frequency to be measured based on the currently connected PCell, thereby performing the frequency measurement.

[0321] The RRC message may contain multiple of the following information types or a part thereof, which can be applied when the UE performs early frequency measurement in the RRC idle mode, the RRC inactive mode, or the RRC connected mode.

[0322] - Configuration information of the frequency to be measured in the RRC idle mode or the RRC inactive mode

[0323] ■ Frequency configuration information

[0324] ◆ LTE frequency measurement information group or list (EUTRA frequency configuration information / list / group)

[0325] ● It can be set to include early measurement settings regarding which frequencies or frequency bands to measure (e.g., a list of frequencies), which order to use for measurement based on frequency priority, which filtering method to use for measuring frequency strength (e.g., L1, L2, or L3 filtering method, or which calculation method and which coefficients to use for measurement), which event or condition to apply to start frequency measurement, which criterion (e.g., signal strength greater than a threshold) will be used for measurement and reporting compared to the current serving cell (or current resident frequency), which event or condition will be applied to report the result of frequency measurement, which criterion or condition the reported frequency needs to meet compared to the current serving cell (or current resident frequency), or which period will be applied to report the result of frequency measurement.

[0326] ◆ NR Frequency Measurement Information Set or List (NR Frequency Configuration Information / List / Group)

[0327] ● It can be set to include early measurement settings regarding which frequencies or frequency bands to measure (e.g., a list of frequencies), which order to use for measurement based on the SSB identifier information, SSB transmission resources (e.g., frequency and time resources, beam identifier or beam indicator, smtc configuration information) of each frequency, or the priority of each frequency (or each SSB), which filtering method to use for measuring frequency strength (e.g., L1, L2, or L3 filtering method, or which calculation method and which coefficients will be used for measurement), which event or condition will be applied to start frequency measurement, which criterion (e.g., signal strength greater than a threshold) will be compared with the current serving cell (or current resident frequency) for measurement and reporting, which event or condition will be applied to report the result of frequency measurement, which criterion or condition the reported frequency needs to meet compared to the current serving cell (or current resident frequency), or which period will be applied to report the result of frequency measurement.

[0328] ■ The duration or timer value (e.g., T331) for performing frequency measurement in RRC idle mode or RRC inactive mode: According to an embodiment, the same timer can be set for LTE frequencies and NR frequencies, or different timers can be set for LTE frequencies and NR frequencies respectively. Due to the different characteristics of LTE frequencies (low frequency bands) and NR frequencies (high frequency bands), using different timers can separately adjust the UE's frequency measurement time, thus saving the UE's battery. For example, if in RRC idle mode or RRC inactive mode, the RRCRelease message instructs frequency measurement, the frequency measurement can be performed while the timer is running and can stop when the timer expires.

[0329] ■ Effective area information for performing frequency measurements in RRC idle mode or RRC inactive mode: In one method, based on a list of physical cell identifiers (PCIDs), when the UE is in the area (e.g., cell) indicated by the area information, the UE can perform frequency measurements, and when it is outside the indicated area, it can stop frequency measurements. For example, when the UE is outside the area, the timer can stop and the frequency measurements can stop. In another method, the base station can use an indicator to instruct the UE transitioning to RRC inactive mode to determine whether to use the RAN indicated area as the effective area. For example, when the base station instructs the UE transitioning to RRC inactive mode to use the RAN indicated area as the effective area through the indicator, the UE can perform frequency measurements within the RAN indicated area while remaining in RRC inactive mode within the RAN indicated area. In yet another method, the base station can instruct the UE to use the effective area as the RAN indicated area through the indicator. In another method, in RRC inactive mode, the UE can apply the RAN indicated area as the effective area without an indicator, and in RRC active mode, a separate effective area can be set for the UE. This proposed method can reduce signaling overhead because the RRC message indicates both the RAN indicated area and the effective area as a list of cell identifiers, and it can also reduce the UE implementation burden because there is no need to separately manage the effective area in UE implementation.

[0330] ■ Measurement report threshold: In a configured frequency group, one or more frequencies with signal strength higher than the threshold can be reported.

[0331] The conditions for the UE to stop early frequency measurements in RRC idle mode or inactive mode can be one or more of the following:

[0332] 1. When the system information of the current cell supports the reporting of early frequency measurement results, and after the UE sends, or when the UE attempts to send an RRC message (e.g., message 5) with measurement results to the base station,

[0333] 2. When the system information of the current cell does not indicate that it supports the reporting of early frequency measurement results,

[0334] 3. When the UE establishes a connection with the network while performing RRC idle mode or RRC inactive mode frequency measurements, stop the timer and measurements when receiving the RRCSetup message or RRCResume message through message 4, and then attempt to send an RRC message (e.g., message 5) to the base station, which indicates that the system information of the current cell supports the reporting of early frequency measurement results and there are measurement results,

[0335] 4. When the measurement report timer (e.g., T331) expires, and

[0336] 5. When the UE is outside the area indicated by the RRC idle mode or RRC inactive mode measurement area information set in the RRC Release message.

[0337] According to one or more of the above conditions, the UE may stop RRC idle mode or RRC inactive mode frequency measurements.

[0338] The UE performs measurements on measurable frequencies in the configuration information related to early frequency measurements, that is, frequencies supported by the UE capabilities (e.g., frequencies available for CA or DC technologies), and at this time the UE may preferentially select specific frequencies to be measured according to a predetermined priority.

[0339] In another method, when area configuration information (i.e., configuration information about the area where the frequency measurement configuration is valid) is set for the UE in the frequency measurement configuration information of the RRC idle mode or RRC inactive mode via the RRC Release message, the UE may stop or restart RRC idle mode or RRC inactive mode frequency measurements based on the system information of the serving cell or the cell identifier, while indicating that the timer indicating the frequency measurement duration is running (if the timer has not expired). Specifically, an RRC idle mode or RRC inactive mode UE moving while performing the cell selection or reselection process may continue to perform frequency measurements, and if the physical cell identifier of the serving cell on which the UE camps is included in the area configuration information, the timer indicating the frequency measurement duration runs. However, if the physical cell identifier of the serving cell on which the UE camps is not included in the area configuration information, the UE may stop frequency measurements, continue to run the timer, and maintain the frequency measurement configuration information set in the RRC message (if frequency measurement information or a frequency measurement list is set in the RRC message). If the UE reselects a cell with a cell identifier included in the area configuration information and camps again, frequency measurements may be restarted while the timer is running (if the timer has not expired). In addition, when the timer indicating the frequency measurement duration expires, the frequency measurement configuration information may be released or discarded.

[0340] -1> When the UE receives an RRC Release message (or when receiving an RRC Release message in response to an RRC ResumeRequest), if the base station does not set frequency measurement configuration information in the RRC Release message or the UE does not receive frequency measurement configuration information (or a frequency measurement list) via the RRC Release message,

[0341] ■2>The UE receives or obtains frequency measurement configuration information for RRC idle mode or RRC inactive mode frequency measurement from the system information (e.g., SIB5) of the serving cell and stores it. Additionally, the UE may perform or restart RRC idle mode or RRC inactive mode frequency measurement according to the frequency measurement configuration information. In an alternative method, if there is no frequency measurement configuration information in the RRC Release message, the UE may determine it as an instruction to stop frequency measurement, stop the frequency measurement, stop the timer, and discard the frequency measurement configuration information or frequency measurement results. In another alternative method, the RRC Release message may define an indicator to discard or retain the frequency measurement configuration information or frequency measurement results.

[0342] -1>When the UE receives an RRC Release message (or when receiving an RRC Release message in response to an RRC Resume Request), if the base station has set frequency measurement configuration information in the RRC Release message, the UE has received the frequency measurement configuration information (or frequency measurement list) through the RRC Release message, or the timer for frequency measurement is running (if the timer has not expired),

[0343] ■2>The UE may discard the stored frequency measurement configuration information or frequency measurement results. In an alternative method, the RRC Release message may define an indicator to discard or maintain the frequency measurement configuration information or frequency measurement results, and may be set to only add, change, or delete part of the stored frequency measurement configuration information.

[0344] ■2>The UE stores or configures the frequency measurement configuration information set in the RRC Release message and performs or restarts RRC idle mode or RRC inactive mode frequency measurement according to this information.

[0345] -1>If the system information of the cell on which the UE is camped indicates support for RRC idle mode or RRC inactive mode frequency measurement, or if the timer for frequency measurement is running (if the timer has not expired),

[0346] -1>Optionally, if the UE camps or re-camps on a cell having a frequency or cell identifier included in the area configuration information (configuration information set in an RRC message (e.g., RRC Release)) for RRC idle mode or RRC inactive mode frequency measurement, or if the timer for frequency measurement is running (if the timer has not expired),

[0347] ■2>If the base station does not set frequency measurement configuration information in the RRC Release message, or if the UE does not receive the frequency measurement configuration (or frequency measurement list) in the RRC Release message,

[0348] ◆3>The UE receives or obtains the frequency measurement configuration information for RRC idle mode or RRC inactive mode frequency measurement in the system information (such as SIB5) of the serving cell and stores it.

[0349] ◆3>The UE performs or restarts RRC idle mode or RRC inactive mode frequency measurement according to the frequency measurement configuration information.

[0350] ■2>If the base station sets frequency measurement configuration information in the RRC Release message, if the UE receives the frequency measurement configuration (or frequency measurement list) in the RRC Release message, or if the timer for frequency measurement is running (if the timer has not expired),

[0351] ◆3>The UE performs or restarts RRC idle mode or RRC inactive mode frequency measurement according to the frequency measurement configuration information set in the RRC Release message.

[0352] -1>If the system information of the cell on which the UE camps does not indicate support for RRC idle mode or RRC inactive mode frequency measurement, or if the timer for frequency measurement is running (if the timer has not expired),

[0353] -1>Alternatively, if the UE camps or re-camps on a cell with a frequency or cell identifier not included in the area configuration information (configuration information set in an RRC message (such as RRC Release)) for RRC idle mode or RRC inactive mode frequency measurement, or if the timer for frequency measurement is running (if the timer has not expired),

[0354] ■2>The UE stops RRC idle mode or RRC inactive mode frequency measurement.

[0355] ■2>(The timer indicating the frequency measurement duration is characterized by continuous operation.)

[0356] Figure 18 is a diagram showing the operations of a terminal according to an embodiment of the present disclosure for performing frequency measurement and reporting measurement results in RRC idle mode or RRC inactive mode.

[0357] In Figure 18In [description], when receiving an RRC message, the UE drives a timer for RRC idle mode or RRC inactive mode frequency measurement, receives frequency measurement configuration information for RRC idle mode or RRC inactive mode frequency measurement (if present in the RRC message) (18-05), or receives frequency measurement configuration information in the system information of the serving cell on which the UE camps through the cell selection or reselection process (18-05), and performs RRC idle mode or RRC inactive mode frequency measurement (18-10). At this time, the UE may perform frequency measurement according to the first, second, third, or fourth embodiment described above. Then, the UE stores the frequency measurement result. If there is an indicator in the system information of the cell that supports RRC idle mode or RRC inactive mode frequency measurement, when establishing a connection with the network, the timer is stopped when receiving message 4 (18-05), and the result of RRC idle mode or RRC inactive mode frequency measurement is notified through message 5. Then, when the base station requests the result of RRC idle mode or RRC inactive mode frequency measurement, the UE reports the measurement result (18-20), and when the measurement result is successfully transmitted to the base station, the measurement result may be discarded.

[0358] Figure 19 is a signal diagram showing the structure of a terminal according to an embodiment of the present disclosure.

[0359] Reference Figure 19 , the terminal (i.e., the UE) may include a radio frequency (RF) processor 19-10, a baseband processor 19-20, a memory 19-30, and a controller 19-40.

[0360] The RF processor 19-10 performs functions of transmitting and receiving signals through a wireless channel, such as frequency band conversion and amplification of signals. That is, the RF processor 19-10 up-converts the baseband signal provided from the baseband processor 19-20 into an RF band signal, transmits the RF band signal via an antenna, and down-converts the RF band signal received via the antenna into a baseband signal. For example, the RF processor 19-10 may include a transmit filter, a receive filter, an amplifier, a mixer, an oscillator, a digital-to-analog converter (DAC), an analog-to-digital converter (ADC), etc. Although only a single antenna is shown in the figure, the terminal may include multiple antennas. In addition, the RF processor 19-10 may include multiple RF chains. In addition, the RF processor 19-10 may perform beamforming. For beamforming, the RF processor 19-10 may control the phase and magnitude of each signal transmitted or received via multiple antennas or antenna elements. In addition, the RF processor may perform MIMO and may receive multiple layers while performing the MIMO operation. The RF processor 19-10 may appropriately configure multiple antennas or antenna elements according to the control of the controller to perform receive beam scanning, or may control the direction and beam width of the receive beam so that the receive beam coincides with the transmit beam.

[0361] The baseband processor 19-20 performs a conversion function between a baseband signal and a bit stream according to the physical layer standard of the system. For example, in the case of data transmission, the baseband processor 19-20 generates complex symbols by encoding and modulating the transmission bit stream. In addition, in the case of data reception, the baseband processor 19-20 reconstructs the received bit stream by demodulating and decoding the baseband signal provided from the RF processor 19-10. For example, in the case of data transmission, according to the OFDM (Orthogonal Frequency Division Multiplexing) scheme, the baseband processor 19-20 generates complex symbols by encoding and modulating the transmission bit stream, maps the complex symbols to subcarriers, and then configures OFDM symbols via an inverse fast Fourier transform (IFFT) operation and cyclic prefix (CP) insertion. In addition, in the case of data reception, the baseband processor 19-20 divides the baseband signal provided from the RF processor 19-10 in units of OFDM symbols, reconstructs the signal mapped to subcarriers via a fast Fourier transform (FFT) operation, and then reconstructs the received bit stream via demodulation and decoding.

[0362] As described above, the baseband processors 19-20 and the RF processors 19-10 transmit or receive signals. Therefore, the baseband processors 19-20 and the RF processors 19-10 may be referred to as transmitters, receivers, transceivers, or communication units. In addition, at least one of the baseband processors 19-20 and the RF processors 19-10 may include multiple communication modules to support many different radio access technologies. In addition, at least one of the baseband processors 19-20 and the RF processors 19-10 may include different communication modules to process signals of different frequency bands. For example, different radio access technologies may include LTE networks, NR networks, etc. In addition, different frequency bands may include super high frequency (SHF) (e.g., 2.5 GHz and 5 GHz) bands and millimeter (mm) wave (e.g., 60 GHz) bands.

[0363] The memory 19-30 stores data, such as basic programs, application programs, and configuration information for the operation of the terminal. The memory 19-30 may provide the stored data in response to a request from the controller 19-40.

[0364] The controller 19-40 may include a multi-connection processor 19-42 and may control the overall operation of the terminal. For example, the controller 19-40 transmits or receives signals through the baseband processors 19-20 and the RF processors 19-10. In addition, the controller 19-40 writes to and reads data from / to the memory 19-40. To this end, the controller 19-40 may include at least one processor. For example, the controller 19-40 may include a communication processor (CP) that performs communication control and an application processor (AP) that controls higher layers such as application programs.

[0365] Figure 20 is a block diagram showing the structure of a base station in a wireless communication system according to an embodiment of the present disclosure.

[0366] Reference Figure 20 , the base station may include an RF processor 20-10, a baseband processor 20-20, a backhaul communication unit 20-30, a memory 20-40, and a controller 20-50.

[0367] The RF processor 20-10 performs functions of transmitting or receiving signals through a wireless channel, such as frequency band conversion and amplification of signals. For example, the RF processor 20-10 up-converts a baseband signal provided from the baseband processor 20-20 into an RF band signal, then transmits the converted signal via an antenna, and down-converts the RF band signal received via the antenna into a baseband signal. For example, the RF processor 20-10 may include a transmit filter, a receive filter, an amplifier, a mixer, an oscillator, a DAC, and an ADC. Although only a single antenna is shown in the figure, the first access node may include multiple antennas. In addition, the RF processor 20-10 may include multiple RF chains. In addition, the RF processor 20-10 may perform beamforming. For beamforming, the RF processor 20-10 may control the phase and magnitude of each signal transmitted or received via multiple antennas or antenna elements. The RF processor may perform downlink MIMO operations by transmitting one or more layers.

[0368] The baseband processor 20-20 performs a function of converting between a baseband signal and a bit stream according to the physical layer standard of the first radio access technology. For example, in the case of data transmission, the baseband processor 20-20 generates complex symbols by encoding and modulating the transmitted bit stream. In addition, in the case of data reception, the baseband processor 20-20 reconstructs the received bit stream by demodulating and decoding the baseband signal provided from the RF processor 20-10. For example, in the case of data transmission, according to the OFDM scheme, the baseband processor 20-20 may generate complex symbols by encoding and modulating the transmitted bit stream, map the complex symbols to subcarriers, and then configure OFDM symbols via IFFT operations and CP insertion. In addition, in the case of data reception, the baseband processor 20-20 divides the baseband signal provided from the RF processor 20-10 in units of OFDM symbols, reconstructs the signal mapped to subcarriers via FFT operations, and then reconstructs the received bit string by demodulating and decoding. As described above, the baseband processor 20-20 and the RF processor 20-10 transmit or receive signals. Therefore, the baseband processor 20-20 and the RF processor 20-10 may be referred to as a transmitter, a receiver, a transceiver, a communication unit, or a wireless communication unit.

[0369] The communication unit 20-30 provides an interface for performing communication with other nodes in the network.

[0370] The memory 20-40 may store data for the operation of the master base station, such as basic programs, application programs, configuration information, etc. In particular, the memory 20-40 may store information associated with the bearers assigned to the connected terminals, measurement results reported from the connected terminals, etc. In addition, the memory 20-40 may store information that serves as a criterion for determining whether to provide or interrupt multi-access to the terminals. Further, the memory 20-40 may provide the stored data in response to a request from the controller 20-50.

[0371] The controller 20-50 may include a multi-connection processor 20-52 and may control the overall operation of the master base station. For example, the controller 20-50 transmits or receives signals via the baseband processor 20-20 and the RF processor 20-10 or via the backhaul communication unit 20-30. In addition, the controller 20-50 writes to and reads data from / to the memory 20-40. To this end, the controller 20-50 may include at least one processor.

[0372] Although the present disclosure has been described with various embodiments, various changes and modifications may be suggested to those skilled in the art. The present disclosure is intended to cover such changes and modifications that fall within the scope of the appended claims.

Claims

1. A method performed by a terminal in a communication system, the method comprising: receiving a Radio Resource Control (RRC) release message, the RRC release message including first configuration information for measurements in RRC idle state or RRC inactive state; receiving a System Information Block (SIB) from a base station; identifying whether the SIB includes second configuration information for measurements in RRC idle state or RRC inactive state, where the second configuration information includes a first frequency and a Synchronization Signal Block (SSB) configuration corresponding to the first frequency, in a case where the first configuration information includes the first frequency and does not include the SSB configuration corresponding to the first frequency; and performing a measurement on the first frequency based on the SSB configuration included in the second configuration information when the terminal is in RRC idle state or RRC inactive state and a timer is running, in a case where the SIB includes the second configuration information including the first frequency and the SSB configuration corresponding to the first frequency.

2. The method according to claim 1, wherein in a case where the RRC release message includes neither a frequency list for New Radio (NR) nor a frequency list for Long Term Evolution (LTE), the method includes: identifying the second configuration information included in the SIB, where the second configuration information includes a second frequency and an SSB configuration corresponding to the second frequency; and performing a measurement on the second frequency based on the SSB configuration corresponding to the second frequency when the terminal is in RRC idle state or RRC inactive state and the timer is running.

3. The method according to claim 1, wherein the SSB configuration includes information about the periodicity, duration, and offset associated with the SSB.

4. The method according to claim 1, wherein the timer is started in response to receiving the RRC release message, and information about the duration of the timer is included in the RRC release message.

5. The method according to claim 1, wherein the measurement is initiated based on cell selection in RRC idle state or RRC inactive state.

6. A terminal in a communication system, the terminal comprising: a transceiver; and a controller configured to: receive a Radio Resource Control (RRC) release message, the RRC release message including first configuration information for measurements in RRC idle state or RRC inactive state, receive a System Information Block (SIB) from a base station, identify whether the SIB includes second configuration information for measurements in RRC idle state or RRC inactive state, where the second configuration information includes a first frequency and an SSB configuration corresponding to the first frequency, in a case where the first configuration information includes the first frequency and does not include the SSB configuration corresponding to the first frequency, and When the SIB includes second configuration information including a first frequency and an SSB configuration corresponding to the first frequency, when the terminal is in the RRC idle state or the RRC inactive state and a timer is running, perform measurements on the first frequency based on the SSB configuration included in the second configuration information.

7. The terminal according to claim 6, wherein, when the RRC release message includes neither a frequency list for New Radio (NR) nor a frequency list for Long Term Evolution (LTE), the controller is further configured to: identify the second configuration information included in the SIB, wherein the second configuration information includes a second frequency and an SSB configuration corresponding to the second frequency; and when the terminal is in the RRC idle state or the RRC inactive state and the timer is running, perform measurements on the second frequency based on the SSB configuration corresponding to the second frequency.

8. The terminal according to claim 6, wherein, the SSB configuration includes information about the periodicity, duration, and offset associated with the SSB.

9. The terminal according to claim 6, wherein, the timer is started in response to receiving the RRC release message, and wherein information about the duration of the timer is included in the RRC release message.

10. The terminal according to claim 6, wherein, the measurement is initiated based on cell selection in the RRC idle state or the RRC inactive state.

11. A method performed by a base station in a communication system, the method comprising: generating a System Information Block (SIB) that includes configuration information for measurements in the Radio Resource Control (RRC) idle state or the RRC inactive state, the configuration information including a first frequency and a Synchronization Signal Block (SSB) configuration corresponding to the first frequency; and transmitting the SIB, wherein when the RRC release message received by the terminal includes the first frequency and does not include the SSB configuration corresponding to the first frequency, when the terminal is in the RRC idle state or the RRC inactive state and a timer is running, the SSB configuration corresponding to the first frequency included in the SIB is used for measurements.

12. The method according to claim 11, wherein, when the RRC release message includes neither a frequency list for New Radio (NR) nor a frequency list for Long Term Evolution (LTE), and the SIB includes configuration information including a second frequency and an SSB configuration corresponding to the second frequency, when the terminal is in the RRC idle state or the RRC inactive state and the timer is running, the SSB configuration corresponding to the second frequency included in the SIB is used for measurements.

13. The method according to claim 11, wherein, the SSB configuration includes information about the periodicity, duration, and offset associated with the SSB.

14. The method according to claim 11, wherein, the timer is started in response to receiving the RRC release message, and Among them, information about the duration of the timer is included in the RRC release message.

15. The method according to claim 11, wherein, the measurement is initiated based on cell selection in the RRC idle state or the RRC inactive state.

16. A base station in a communication system, the base station comprising: a transceiver; and a controller configured to: generate a system information block SIB, the SIB including configuration information for measurements in the radio resource control RRC idle state or the RRC inactive state, the configuration information including a first frequency and a synchronization signal block SSB configuration corresponding to the first frequency, and transmit the SIB, wherein, when the RRC release message received in the terminal includes the first frequency and does not include the SSB configuration corresponding to the first frequency, and when the terminal is in the RRC idle state or the RRC inactive state and the timer is running, the SSB configuration corresponding to the first frequency included in the SIB is used for measurement.

17. The base station according to claim 16, wherein, when the RRC release message includes neither a frequency list for New Radio NR nor a frequency list for Long Term Evolution LTE, and the SIB includes configuration information including a second frequency and an SSB configuration corresponding to the second frequency, and when the terminal is in the RRC idle state or the RRC inactive state and the timer is running, the SSB configuration corresponding to the second frequency included in the SIB is used for measurement.

18. The base station according to claim 16, wherein, the SSB configuration includes information about the periodicity, duration, and offset associated with the SSB.

19. The base station according to claim 16, wherein, the timer is started in response to the reception of the RRC release message, and wherein, information about the duration of the timer is included in the RRC release message.

20. The base station according to claim 16, wherein, the measurement is initiated based on cell selection in the RRC idle state or the RRC inactive state.

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