KR20210120372A - Method and apparatus for performing the idle mode and inactive mode procedure in a wireless communication system - Google Patents

Abstract

The present invention relates to a method for performing an idle mode operation or an inactive mode operation in a wireless communication system to effectively perform the idle mode operation or the inactive mode operation. According to one embodiment of the present invention, the method may comprise the following steps of: receiving a request for collection of public land mobile network (PLMN) information from a non-access stratum (NAS) of a terminal in an access stratum (AS) of the terminal; scanning all carriers in a frequency band supportable by the AS on the basis of the received request from the AS of the terminal; identifying a cell providing a signal with a maximum size on the basis of a scan result in the AS of the terminal; obtaining the PLMN information of the cell from system information of the identified cell providing the signal with the maximum size in the AS of the terminal; and reporting the acquired PLMN information of the cell from the AS of the terminal to the NAS of the terminal.

Description

METHOD AND APPARATUS FOR PERFORMING THE IDLE MODE AND INACTIVE MODE PROCEDURE IN A WIRELESS COMMUNICATION SYSTEM

The present disclosure relates to a wireless communication system, and more particularly, to a method and apparatus for performing standby mode or inactive mode operation.

Efforts are being made to develop an improved 5G communication system or pre-5G communication system in order to meet the increasing demand for wireless data traffic after commercialization of the 4G communication system. For this reason, the 5G communication system or the pre-5G communication system is called a system after the 4G network (Beyond 4G Network) communication system or after the LTE system (Post LTE). In order to achieve a high data rate, the 5G communication system is being considered for implementation in a very high frequency (mmWave) band (eg, such as a 60 gigabyte (60 GHz) band). In order to alleviate the path loss of radio waves and increase the propagation distance of radio waves in the very high frequency band, in the 5G communication system, beamforming, massive MIMO, full dimensional MIMO, FD-MIMO ), array antenna, analog beam-forming, and large scale antenna technologies are being discussed. In addition, for network improvement of the system, in the 5G communication system, an evolved small cell, an advanced small cell, a cloud radio access network (cloud RAN), and an ultra-dense network (ultra-dense network) , Device to Device communication (D2D), wireless backhaul, moving network, cooperative communication, Coordinated Multi-Points (CoMP), and interference cancellation Technology development is underway. In addition, in the 5G system, advanced coding modulation (ACM) methods such as FQAM (Hybrid FSK and QAM Modulation) and SWSC (Sliding Window Superposition Coding), and advanced access technologies such as FBMC (Filter Bank Multi Carrier), NOMA (non orthogonal multiple access), and sparse code multiple access (SCMA) are being developed.

On the other hand, the Internet is evolving from a human-centered connection network where humans create and consume information, to an Internet of Things (IoT) network that exchanges and processes information between distributed components such as objects. Internet of Everything (IoE) technology, which combines big data processing technology through connection with cloud servers, etc. with IoT technology, is also emerging. In order to implement IoT, technology elements such as sensing technology, wired and wireless communication and network infrastructure, service interface technology, and security technology are required, and recently, a sensor network for connection between objects, and machine to machine communication (Machine to Machine) are required. , M2M), and MTC (Machine Type Communication) are being studied. In the IoT environment, intelligent IT (Internet Technology) services that create new values in human life by collecting and analyzing data generated from connected objects can be provided. IoT is a field of smart home, smart building, smart city, smart car or connected car, smart grid, health care, smart home appliance, advanced medical service, etc. can be applied to

Accordingly, various attempts are being made to apply the 5G communication system to the IoT network. For example, in technologies such as sensor network, machine to machine (M2M), and machine type communication (MTC), 5G communication technology is implemented by techniques such as beamforming, MIMO, and array antenna. there will be The application of a cloud radio access network (cloud RAN) as the big data processing technology described above is an example of the convergence of 5G technology and IoT technology.

As various services can be provided according to the above-mentioned and the development of mobile communication systems, there is a need for a method for effectively performing a standby mode or an inactive mode operation.

The disclosed embodiments are intended to provide an apparatus and method capable of effectively performing a standby mode or an inactive mode operation in a wireless communication system.

The method of operating a terminal in a wireless communication system according to an embodiment comprises the steps of receiving a request for collection of PLMN information from a NAS (Non-Access Stratum) of the terminal in an Access Stratum (AS) of the terminal, Based on the received request from the AS, the AS scans all carriers in a supportable frequency band, based on the scan result in the AS of the terminal, identifying a cell providing a signal of the maximum size , obtaining the PLMN information of the cell from the system information of the cell providing the identified maximum signal in the AS of the terminal, and the PLMN information of the obtained cell in the AS of the terminal to the NAS of the terminal Reporting may be included.

The disclosed embodiment provides an apparatus and method capable of effectively performing a standby mode or an inactive mode operation in a wireless communication system.

1A is a diagram illustrating a structure of a next-generation wireless communication system according to an embodiment of the present disclosure.
1B is a flowchart of an access stratum (AS) operation of a terminal for acquiring public land mobile network (PLMN) information in a wireless communication system according to an embodiment of the present disclosure.
1C is a diagram for explaining a process of performing terminal access control in a wireless communication system according to an embodiment of the present disclosure.
1D is a flowchart of a process of performing access control in a wireless communication system according to an embodiment of the present disclosure.
FIG. 1e shows priority information for each frequency for cell reselection in a wireless communication system according to an embodiment of the present disclosure is broadcast through a system information block (SIB) or applied to a specific terminal through an RRC Release message that is dedicated RRC signaling It is a drawing for explaining the process.
1F is a diagram for explaining a method for a terminal to perform cell reselection in a wireless communication system according to an embodiment of the present disclosure.
1G is a flowchart of a process in which an NR-light terminal performs a standby mode/inactive mode operation according to an embodiment of the present disclosure.
1H is a flowchart of a process in which an NR-light terminal performs a PLMN selection operation according to an embodiment of the present disclosure.
1I is a flowchart of a process in which an NR-light terminal performs an Access Control operation according to an embodiment of the present disclosure.
1J is a flowchart of a process in which an NR-light terminal performs a cell reselection operation according to an embodiment of the present disclosure.
1K is a block diagram illustrating an internal structure of a terminal according to an embodiment of the present disclosure.
11 is a block diagram illustrating a configuration of a base station according to an embodiment of the present disclosure.

In the following description of the present disclosure, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present disclosure, the detailed description thereof will be omitted. Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings.

Advantages and features of the present disclosure, and a method of achieving them will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present disclosure is not limited to the embodiments disclosed below, but may be implemented in various different forms, and only the present embodiments allow the disclosure of the present disclosure to be complete, and common knowledge in the art to which the present disclosure pertains. It is provided to fully inform the possessor of the scope of the invention, and the present disclosure is only defined by the scope of the claims. Like reference numerals refer to like elements throughout.

At this time, it will be understood that each block of the flowchart diagrams and combinations of the flowchart diagrams may be performed by computer program instructions. These computer program instructions may be embodied in a processor of a general purpose computer, special purpose computer, or other programmable data processing equipment, such that the instructions performed by the processor of the computer or other programmable data processing equipment are not described in the flowchart block(s). It creates a means to perform functions. These computer program instructions may also be stored in a computer-usable or computer-readable memory that may direct a computer or other programmable data processing equipment to implement a function in a particular manner, and thus the computer-usable or computer-readable memory. It is also possible that the instructions stored in the flow chart block(s) produce an article of manufacture containing instruction means for performing the function described in the flowchart block(s). The computer program instructions may also be mounted on a computer or other programmable data processing equipment, such that a series of operational steps are performed on the computer or other programmable data processing equipment to create a computer-executed process to create a computer or other programmable data processing equipment. It is also possible that instructions for performing the processing equipment provide steps for performing the functions described in the flowchart block(s).

Additionally, each block may represent a module, segment, or portion of code that includes one or more executable instructions for executing specified logical function(s). It should also be noted that in some alternative implementations it is also possible for the functions recited in blocks to occur out of order. For example, two blocks shown one after another may in fact be performed substantially simultaneously, or it is possible that the blocks are sometimes performed in the reverse order according to the corresponding function.

In this case, the term '~ unit' used in this embodiment means software or hardware components such as FPGA (Field Programmable Gate Array) or ASIC (Application Specific Integrated Circuit), and '~ unit' performs certain roles do. However, '-part' is not limited to software or hardware. The '~ unit' may be configured to reside on an addressable storage medium or may be configured to refresh one or more processors. Thus, as an example, '~' denotes components such as software components, object-oriented software components, class components, and task components, and processes, functions, properties, and procedures. , subroutines, segments of program code, drivers, firmware, microcode, circuitry, data, databases, data structures, tables, arrays, and variables. The functions provided in the components and '~ units' may be combined into a smaller number of components and '~ units' or further separated into additional components and '~ units'. In addition, components and '~ units' may be implemented to play one or more CPUs in a device or secure multimedia card. Also, in an embodiment, '~ unit' may include one or more processors.

In the following description of the present disclosure, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present disclosure, the detailed description thereof will be omitted. Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings.

A term for identifying an access node used in the following description, a term referring to a network entity (network entity), a term referring to messages, a term referring to an interface between network objects, and various identification information Reference terms and the like are exemplified for convenience of description. Accordingly, the present disclosure is not limited to the terms described below, and other terms referring to objects having equivalent technical meanings may be used.

For convenience of description, the present disclosure uses terms and names defined in the 3rd Generation Partnership Project Long Term Evolution (3GPP LTE) standard. However, the present disclosure is not limited by the above terms and names, and may be equally applied to systems conforming to other standards. In the present disclosure, eNB may be used interchangeably with gNB for convenience of description. That is, a base station described as an eNB may represent a gNB. Also, the term terminal may refer to mobile phones, NB-IoT devices, sensors, as well as other wireless communication devices.

Hereinafter, the base station is a subject that performs resource allocation of the terminal, and may be at least one of gNode B, eNode B, Node B, a base station (BS), a radio access unit, a base station controller, or a node on a network. The terminal may include a user equipment (UE), a mobile station (MS), a cellular phone, a smart phone, a computer, or a multimedia system capable of performing a communication function. Of course, it is not limited to the above example.

In particular, the present disclosure is applicable to 3GPP NR (5th generation mobile communication standard). In addition, the present disclosure provides intelligent services (eg, smart home, smart building, smart city, smart car or connected car, healthcare, digital education, retail business, security and safety-related services based on 5G communication technology and IoT-related technology) etc.) can be applied. In the present invention, eNB may be used interchangeably with gNB for convenience of description. That is, a base station described as an eNB may represent a gNB. Also, the term terminal may refer to mobile phones, NB-IoT devices, sensors, as well as other wireless communication devices.

A wireless communication system, for example, 3GPP's HSPA (High Speed Packet Access), LTE (Long Term Evolution or E-UTRA (Evolved Universal Terrestrial Radio Access)), LTE-Advanced (LTE-A), LTE-Pro, 3GPP2's High Rate Packet Data (HRPD), UMB (Ultra Mobile Broadband), and IEEE's 802.16e, such as communication standards such as communication standards such as broadband wireless that provides high-speed, high-quality packet data service It is evolving into a communication system.

As a representative example of a broadband wireless communication system, in an LTE system, an Orthogonal Frequency Division Multiplexing (OFDM) scheme is employed in a downlink (DL; DownLink), and Single Carrier Frequency Division Multiple Access (SC-FDMA) in an uplink (UL). ) method is used. Uplink refers to a radio link in which a UE (User Equipment or MS; Mobile Station) transmits data or control signals to a base station (eNode B or BS; Base Station), and downlink refers to a radio link in which the base station transmits data or control to the UE A radio link that transmits signals. The multiple access method as described above divides the data or control information of each user by allocating and operating the time-frequency resources to which data or control information is to be transmitted for each user so that they do not overlap each other, that is, orthogonality is established. .

As a future communication system after LTE, that is, the 5G communication system must be able to freely reflect various requirements such as users and service providers, so services that simultaneously satisfy various requirements must be supported. Services considered for the 5G communication system include Enhanced Mobile BroadBand (eMBB), massive Machine Type Communication (mMTC), and Ultra Reliability Low Latency Communication (URLLC). There is this.

According to some embodiments, the eMBB may aim to provide a data transfer rate that is more improved than the data transfer rate supported by the existing LTE, LTE-A, or LTE-Pro. For example, in the 5G communication system, the eMBB should be able to provide a maximum data rate of 20 Gbps in the downlink and a maximum data rate of 10 Gbps in the uplink from the viewpoint of one base station. In addition, the 5G communication system may have to provide the maximum transmission speed and at the same time provide the increased user perceived data rate of the terminal. In order to satisfy such a requirement, in the 5G communication system, it may be required to improve various transmission/reception technologies, including a more advanced multi-antenna (MIMO) transmission technology. In addition, while transmitting signals using a transmission bandwidth of up to 20 MHz in the 2 GHz band currently used by LTE, the 5G communication system uses a frequency bandwidth wider than 20 MHz in the frequency band of 3 to 6 GHz or 6 GHz or more Data transfer speed can be satisfied.

At the same time, mMTC is being considered to support application services such as the Internet of Things (IoT) in the 5G communication system. In order to efficiently provide the Internet of Things, mMTC may require large-scale terminal access support, improved terminal coverage, improved battery life, and reduced terminal cost within a cell. Since the Internet of Things is attached to various sensors and various devices to provide communication functions, it must be able to support a large number of terminals (eg, 1,000,000 terminals/km2) within a cell. In addition, since the terminal supporting mMTC is highly likely to be located in a shaded area that the cell does not cover, such as the basement of a building, due to the nature of the service, wider coverage may be required compared to other services provided by the 5G communication system. A terminal supporting mMTC should be composed of a low-cost terminal, and since it is difficult to frequently exchange the battery of the terminal, a very long battery life time such as 10 to 15 years may be required.

Finally, in the case of URLLC, as a cellular-based wireless communication service used for a specific purpose (mission-critical), remote control for a robot or a machine, industrial automation, It may be used for a service used in an unmanned aerial vehicle, remote health care, emergency alert, and the like. Therefore, the communication provided by URLLC may have to provide very low latency (ultra-low latency) and very high reliability (ultra-reliability). For example, a service supporting URLLC must satisfy an air interface latency of less than 0.5 milliseconds, and at the same time may have a requirement of a packet error rate of 10-5 or less. Therefore, for a service supporting URLLC, the 5G system must provide a smaller Transmit Time Interval (TTI) than other services, and at the same time, it is a design that requires a wide resource allocation in the frequency band to secure the reliability of the communication link. items may be required.

The three services considered in the above-described 5G communication system, ie, eMBB, URLLC, and mMTC, may be multiplexed and transmitted in one system. In this case, different transmission/reception techniques and transmission/reception parameters may be used between services to satisfy different requirements of each service. However, the aforementioned mMTC, URLLC, and eMBB are only examples of different service types, and the service types to which the present disclosure is applied are not limited to the above-described examples.

In addition, although the embodiment of the present invention will be described below using an LTE, LTE-A, LTE Pro or 5G (or NR, next-generation mobile communication) system as an example, the present invention is also applied to other communication systems having a similar technical background or channel type. An embodiment of can be applied. In addition, the embodiments of the present invention can be applied to other communication systems through some modifications within the scope of the present invention as judged by a person having skilled technical knowledge.

1A is a diagram illustrating a structure of a next-generation wireless communication system according to an embodiment of the present disclosure.

Referring to FIG. 1a, as shown, the radio access network of a next-generation wireless communication system (New Radio, NR) includes a next-generation base station (New Radio Node B, hereinafter gNB) (1a-10) and an AMF (1a-05, New Radio). Core Network). A user terminal (New Radio User Equipment, hereinafter NR UE or terminal) 1a-15 may access an external network through gNB 1a-10 and AMF 1a-05.

In FIG. 1A , a gNB corresponds to an Evolved Node B (eNB) of an existing LTE system. The gNB is connected to the NR UE through a radio channel and can provide a service superior to that of the existing Node B (1a-20). In the next-generation wireless communication system, since all user traffic is serviced through a shared channel, a device for scheduling by collecting status information such as the buffer status of UEs, the available transmission power status, and the channel status is required. 1a-10) may be in charge. One gNB can usually control a plurality of cells. In the next-generation wireless communication system, it can have more than the existing maximum bandwidth in order to implement ultra-high-speed data transmission compared to the existing LTE, and additionally beamforming technology using Orthogonal Frequency Division Multiplexing (hereinafter referred to as OFDM) as a radio access technology. this can be used

Also, according to some embodiments, the NR gNB uses an Adaptive Modulation & Coding (AMC) scheme for determining a modulation scheme and a channel coding rate according to the channel state of the UE. can be applied.

Also, according to some embodiments, the AMF 1a-05 may perform functions such as mobility support, bearer setup, QoS setup, and the like. The AMF is a device in charge of various control functions as well as a mobility management function for the terminal, and can be connected to a plurality of base stations. In addition, the next-generation wireless communication system may be interlocked with the existing LTE system, and the AMF may be connected to the Mobility Management Entity (MME) 1a-25 through a network interface. The MME may be connected to the existing base station eNB (1a-30). A UE supporting LTE-NR Dual Connectivity may transmit/receive data while maintaining a connection to not only the gNB but also the eNB (1a-35).

1B is a flowchart of an Access Stratum (AS) operation of a terminal for acquiring Public Land Mobile Network (PLMN) information in a wireless communication system according to an embodiment of the present disclosure.

In step 1b-05, the AS of the terminal may be requested to collect PLMN information from the NAS (Non-Access Stratum) of the terminal. The terminal is largely divided into logical entities of AS and NAS, and the role of each entity may be different. As an example, the AS of the terminal performs RRC connection management, RB control, Mobility functions, UE measurement reporting and control, etc., and the NAS of the terminal may perform bearer management, Authentication, ECM-IDLE mobility handling, security control, etc. .

In step 1b-10, the AS of the terminal may scan for all RF channels (carriers) within the frequency band it can support. In implementation, the UE may scan for several stored RF channels.

In step 1b-15, the AS of the terminal may find a cell providing the strongest signal strength for each carrier, and may obtain PLMN information from system information broadcast by the corresponding cell. In LTE, it is assumed that all cells belonging to one carrier support the same PLMN. In addition, it is assumed that all PLMN information contained in the system information broadcast by the corresponding cells is the same. Therefore, it is sufficient for the UE to acquire PLMN information only from a cell providing the strongest signal strength for each carrier.

In step 1b-20, the AS of the terminal may report the PLMN information collected for each carrier to the terminal NAS. If the signal strength of the cell that provided the collected PLMN is better than a specific threshold, the corresponding PLMN may be indicated as a high quality PLMN and reported to the NAS of the UE. As an example, if the signal strength of the cell is equal to or greater than -110 dBm, the PLMN may be considered as a high quality PLMN. If, the PLMN collected from a cell having a signal strength lower than the threshold value may be reported to the NAS of the terminal together with the RSRP (Reference Signal Received Power) value of the cell. In the present disclosure, a threshold value (eg, -110 dBm) is referred to as a first threshold value. In LTE, the value of the first threshold is predetermined.

1C is a diagram for explaining a process of performing terminal access control in a wireless communication system according to an embodiment of the present disclosure.

Referring to FIG. 1C , the present disclosure proposes a method of effectively providing access control configuration information based on an access identity and an access category. The access identity is the indication information defined within 3GPP, that is, specified in the standard document. The access identity may be used to indicate specific access as shown in [Table 1] below. Mainly, it is possible to indicate accesses classified into Access Class 11 to 15, a multimedia service (Multimedia Priority Service, MPS), and a special purpose service (Mission Critical Service, MCS). Access Class 11 to 15 may indicate access for use only for business operators or for public purposes.

[Table 1]

Access categories can be divided into two types. One is the standardized access category. A standardized access category is a category defined at the RAN level, that is, specified in a standard document. Therefore, the same standardized access category is applied to different operators. In the present disclosure, a category corresponding to Emergency may belong to a standardized access category. All accesses may correspond to at least one of standardized access categories. Another category is the operator-specific (non-standardized) access category. Operator-specific (non-standardized) access categories are defined outside of 3GPP and are not specified in standard documents. Therefore, the meaning of one operator-specific access category may be different for each operator. This may have the same characteristics as the category in the existing ACDC (Application specific Congestion control for Data Communication). Any access triggered by the terminal's NAS may not be mapped to an operator-specific access category. The major difference from the existing ACDC is that the operator-specific (non-standardized) access category does not correspond to only the application, but other factors other than the application, namely, service type, call type, terminal type, user group, signaling type, slice type, or the above. The point is that it can also correspond to a combination of elements. That is, whether to grant access to accesses belonging to other elements may be controlled. The corresponding access category is used to indicate specific access as shown in [Table 2] below. Access categories 0 to 7 are used to indicate standardized access categories, and access categories 32 to 63 can be used to indicate operator-specific access categories.

[Table 2]

The operator server 1c-25 may provide information (Management Object, MO) on operator-specific access category information to the terminal NAS through NAS signaling or application-level data transmission. The information may include information on which element each operator-specific category corresponds to, such as an application. For example, it may be specified in the corresponding information that access category No. 32 corresponds to an access corresponding to the Facebook application. The base station 1c-20 provides a category list providing barring configuration information and barring configuration information information corresponding to each category to the terminals by using the system information. The terminal 1c-05 includes logical blocks of the NAS 1c-10 and the AS 1c-15.

The NAS of the terminal may map the triggered access to one or more access identities and one access category according to a predetermined rule. The mapping operation may be performed in all RRC states, that is, the connected mode (RRC_CONNECTED), the standby mode (RRC_IDLE), and the inactive mode (RRC_INACTIVE). The characteristics of each RRC state are listed as follows.

RRC_IDLE:

- A UE specific DRX may be configured by upper layers;

- UE controlled mobility based on network configuration;

- The UE:

- Monitors a Paging channel;

- Performs neighbouring cell measurements and cell (re-)selection;

- Acquires system information.

RRC_INACTIVE:

- A UE specific DRX may be configured by upper layers or by RRC layer;

- UE controlled mobility based on network configuration;

- The UE stores the AS context;

- The UE:

- Monitors a Paging channel;

- Performs neighbouring cell measurements and cell (re-)selection;

- Performs RAN-based notification area updates when moving outside the RAN-based notification area;

- Acquires system information.

RRC_CONNECTED:

- The UE stores the AS context;

- Transfer of unicast data to/from UE;

- At lower layers, the UE may be configured with a UE specific DRX;

- For UEs supporting CA, use of one or more SCells, aggregated with the SpCell, for increased bandwidth;

- For UEs supporting DC, use of one SCG, aggregated with the MCG, for increased bandwidth;

- Network controlled mobility, i.e. handover within NR and to/from E-UTRAN.

- The UE:

- Monitors a Paging channel;

- Monitors control channels associated with the shared data channel to determine if data is scheduled for it;

- Provides channel quality and feedback information;

- Performs neighbouring cell measurements and measurement reporting;

- Acquires system information.

As another option, in the access category mapping, one access may be mapped to one standardized access category and, if possible, additionally mapped to one operator-specific access category. The NAS of the terminal may transmit the mapped access identity and access category along with the Service Request to the AS of the terminal.

If the AS of the terminal receives access identity or access category information together with the message received from the NAS of the terminal in all RRC states, before performing the wireless connection caused by the message, a barring check operation to determine whether this is allowed can be done If wireless access is allowed through the barring check operation, the terminal may request RRC connection establishment from the network. As an example, the NAS of the connected mode or inactive mode terminal may transmit an access identity and an access category to the AS of the terminal for the following reason (1c-30). In the present disclosure, the following reasons are collectively referred to as 'new session request'.

- new MMTEL voice or video session

- sending of SMS (SMS over IP, or SMS over NAS)

- new PDU session establishment

- existing PDU session modification

- service request to re-establish the user plane for an existing PDU session

On the other hand, the NAS of the standby mode terminal may transmit an access identity and an access category to the AS of the terminal when making a service request.

The AS of the terminal may determine whether access triggered by the NAS of the terminal is permitted by using the barring configuration information information (barring check).

An operator may wish to allow only a specific service type among accesses corresponding to at least one of Access Class 11 to 15. Accordingly, in the present disclosure, it may be characterized in that it is determined whether access belonging to Access Classes 11, 12, 13, 14, and 15 indicated by an access identity is allowed according to an attribute distinguished by an access category. To this end, we propose a method of configuring barring configuration information of an access identity or an access category. In the present disclosure, it is assumed that the barring configuration information of the access category consists of ac-barringFactor and ac-barringTime like the conventional barring configuration information of ACB or ACDC.

1D is a flowchart of a process of performing access control in a wireless communication system according to an embodiment of the present disclosure.

Referring to FIG. 1D , a terminal 1d-05 may be configured with a NAS 1d-10 and an AS 1d-15. The NAS is in charge of processes not directly related to wireless access, ie, authentication, service request, session management, etc., whereas the AS may be in charge of processes related to wireless access. The network 1d-20 may provide management object information to the NAS using an OAM (Operations, Administration and Maintenance) (application-level data message) or NAS message (1d-25). The management object information may include information on whether each operator-specific access category corresponds to an element such as an application. The NAS may use the management object information to determine which operator-specific category a triggered access is mapped to. The triggered access may correspond to a new multimedia telephony (MMTEL) service (voice call, video call), SMS transmission, establishment of a new PDU session, change of an existing PDU session, and the like. When a service is triggered, the NAS may map an access identity corresponding to an attribute of the service and an access category (1d-30). A corresponding service may not be mapped to any access identities, or may be mapped to one or more access identities. Also, the corresponding service may be mapped to one access category. Assuming that one access category can be mapped, it can be checked first whether the corresponding service is mapped with the operator-specific access category provided by the management object. If it does not map to any operator-specific access category, it can be mapped to one of the standardized access categories that can be mapped. Assuming that multiple access categories can be mapped, one service can be mapped with one operator-specific access category and one standardized access category. However, if it does not map to any operator-specific access category, it can be mapped to any corresponding one of the standardized access categories. In the mapping rule, emergency service may be an exception. The NAS may transmit a new session request or Service Request to the AS along with the mapped access identity and access category (1d-40). The NAS can send a new session request in connected mode or inactive mode, and a service request in standby mode. The AS may receive barring configuration information from system information broadcast by the network (1d-35). An example of the ASN.1 structure of the barring configuration information is as follows, and a detailed description thereof will be described later.

α < 1일 수 있다. 단말의 AS는 0

rand < 1인 하나의 랜덤 값 rand을 도출하며, 랜덤 값이 uac-BarringFactor보다 작으면 엑세스가 금지되지 않은 것으로, 그렇지 않다면 엑세스가 금지된 것으로 간주할 수 있다. 엑세스가 금지된 것으로 결정되면, 단말의 AS는 아래의 [수학식 1]을 이용하여 도출된 소정의 시간 동안 엑세스 시도를 지연시킬 수 있다. 단말의 AS는 해당 시간 값을 가지는 타이머를 구동시킬 수 있다. 본 개시에서는 해당 타이머를 barring timer라 칭한다.The AS may determine whether the service request is permitted by using the access identity and access category information mapped by the NAS and the corresponding barring configuration information received from the network (1d-45). In the present disclosure, an operation of determining whether a service request is permitted is referred to as a barring check. The terminal may receive system information including access control configuration information and store the corresponding configuration information. Barring configuration information may be provided for each PLMN and each access category. The BarringPerCatList IE (Information Element) may be used to provide barring configuration information of access categories belonging to one PLMN. To this end, the PLMN id and barring configuration information of each access category may be included in the IE in the form of a list. Barring configuration information for each access category may include an access category id (or index) indicating a specific access category, uac-BarringForAccessIdentity field, uac-BarringFactor field, and uac-Barringtime field. The operation of the aforementioned barring check may be as follows. First, each bit constituting uac-BarringForAccessIdentityList corresponds to one access identity, and when the corresponding bit value is indicated as '0', access related to the access identity may be allowed. For at least one of the mapped access identities, access may be allowed if at least one of the corresponding bits in uac-BarringForAccessIdentity is '0'. For at least one of the mapped access identities, if none of the corresponding bits in the uac-BarringForAccessIdentity is '0', an additional barring check described below may be additionally performed using the uac-BarringFactor field. The range of uac-BarringFactor α is 0

α<1. The AS of the terminal is 0

A single random value rand with rand < 1 is derived. If the random value is less than uac-BarringFactor, access is not prohibited, otherwise, access can be regarded as prohibited. If it is determined that access is prohibited, the AS of the terminal may delay the access attempt for a predetermined time derived using [Equation 1] below. The AS of the terminal may drive a timer having a corresponding time value. In the present disclosure, the corresponding timer is referred to as a barring timer.

[Equation 1]

"Tbarring" = (0.7+ 0.6 * rand) * uac-BarringTime

If access is prohibited, the AS of the terminal may notify the NAS of the terminal. And, when the derived predetermined time expires, the AS of the terminal may inform the NAS of the terminal that it can request access again (barring alleviation). From this point on, the NAS of the terminal may request access to the AS of the terminal again.

According to a predetermined rule, when a service request is allowed, the AS may request RRC connection establishment or RRC connection resume to the network or transmit data related to a new session (1d-50).

FIG. 1e shows priority information for each frequency for cell reselection in a wireless communication system according to an embodiment of the present disclosure is broadcast through a system information block (SIB) or applied to a specific terminal through an RRC Release message that is dedicated RRC signaling It is a drawing for explaining the process.

Referring to FIG. 1E , cell reselection is a process of reselecting a serving cell so that a mobile terminal can be connected to a cell having the best channel state. The network controls cell reselection of terminals in standby mode by giving priority to each frequency. For example, if a terminal receives priority information for two frequencies f1 and f2, and f1 has a higher priority than f2, the probability that the terminal stays in f1 increases. Also, even if the terminal is in f2, if the channel state of f2 is not good, it will try to change to f1. Priority information on a frequency is broadcast through SIB or provided to a specific UE through an RRC Release message that is dedicated RRC signaling. Even if the UE already has priority information on frequencies through the SIB, if UE-specific priority information is provided through RRC signaling, the priority information of the SIB is ignored. Priority information of each frequency is delivered through the following cellReselectionPriority IE, and is given one of the priorities of the total X+1 steps. A lower value means a lower priority. That is, '0' means the lowest priority.

Frequencies between RATs (Radio Access Technology) cannot be given the same priority. If the IDLE state of the UE is 'camped on any cell state', the frequency priority information received through the SIB is applied, and the priority information received through the RRC signaling can only be stored without using it. The cellReselectionPriority IE is an optional IE and may not exist. In this case, priority information for the corresponding frequency is not given. At this time, the terminal considers the priority of the corresponding frequency as the lowest level. In step 1e-00, the UE may be provided with priority information on frequencies used in other RATs as well as Evolved Universal Terrestrial Radio Access (EUTRA) through the SIB. However, priority information is not necessarily provided for all frequencies. Priority information on the frequency of the currently camped serving cell may not be provided either. The UE may check whether priority information exists in step 1e-05. If priority information on the frequency of the current serving cell is not provided, the UE may regard the priority of the frequency as the lowest level. The UE may apply priority information of each frequency in steps 1e-15. Upon receiving the RRC Release message from the base station, the terminal may switch from the connected mode to the idle mode (IDLE mode). The RRC message may include frequency priority information. This is UE-specific information, and may generally be applied preferentially to frequency priority information provided from the SIB. Accordingly, the UE may check whether the frequency priority information is present in the RRC message in step 1e-20. If present, the terminal may drive the first timer by applying the included first timer value in steps 1e-25. The UE may determine whether the current standby mode state is 'camped on any cell state' or 'camped normally state' in steps 1e-30. The 'camped normally state' refers to a state in which the terminal is camping in a suitable cell. A suitable cell is a cell that can provide a normal service to a UE, and is a cell that satisfies the following detailed conditions.

- A cell corresponds to a selected PLMN, registered PLMN, or one PLMN in the equivalent PLMN list

- unbarred cells

- Cells that satisfy the cell selection criterion

- 'camped on any cell state' refers to a state in which the terminal cannot camp on a suitable cell, and is camped on an acceptable cell. In an acceptable cell, a general service is not possible, and only an emergency call can be attempted by the terminal. An acceptable cell is a cell that satisfies the following conditions.

- unbarred cells

- Cells that satisfy the cell selection criterion

If the terminal is in the 'camped on any cell state' standby state, instead of the priority information provided from the RRC Connection Release message, it returns to step 1e-15 and the terminal may apply the frequency priority information provided from the SIB. If the terminal is in a 'camped normally' standby state, the terminal may determine whether at least one of the following three conditions is satisfied in steps 1e-35. the three conditions

- The terminal is switched to connected mode

- First timer expired

- Upon NAS request, the PLMN selection process is performed

If any of the above conditions are satisfied, the priority information provided from the RRC Release message in step 1e-40 is discarded, and the UE returns to step 1e-15 and applies the frequency priority information provided from the SIB. can do. Otherwise, if none of the conditions are satisfied, the UE may apply the priority information provided from the RRC Release message in steps 1e-45.

The frequency priority information may affect the measurement of a specific frequency by the UE. For a frequency having a higher priority than the current serving cell, the UE may always perform measurement. On the other hand, for the same frequency as the serving cell (intra-frequency) or another frequency having the same or lower priority than this, in order to save terminal power, the measurement of the corresponding frequency may not always be performed. Whether to perform the measurement may be performed when the channel QoS of the serving cell is less than or equal to a specific threshold. Cell reselection is performed to move to a cell with a good channel state, and there is no reason to move to a frequency with the same priority or lower priority even though the channel QoS of the current serving cell is good. Therefore, in order to reduce power consumption due to unnecessary channel measurement, whether to perform measurement may be determined based on a specific threshold. In the case of the same frequency (intra-frequency), if the QoS of the serving cell is the same or lower than the specific threshold Sintrasearch, channel measurement may be performed for other cells of the same frequency. For other frequencies having the same or lower priority, if the QoS of the serving cell is the same or lower than the specific threshold Snonintrasearch, channel measurement may be performed for cells of the other frequency. Channel QoS can generally consider RSRP and RSRQ.

While performing the measurement as described above, if the channel QoS of the cell of the high priority frequency becomes higher than the specific threshold ThreshX-high, the terminal may reselect the cell of the high priority frequency as the serving cell. If the channel QoS of the cell of the low priority frequency is higher than the specific threshold ThreshX-low and the QoS of the serving cell is lower than ThreshServing-low, the UE can reselect the cell of the low priority frequency as the serving cell.

1F is a diagram for explaining a method for a terminal to perform cell reselection in a wireless communication system according to an embodiment of the present disclosure.

Referring to FIG. 1F , the UE may always perform inter-freq/RAT measurement on a high-priority frequency or RAT regardless of the measurement signal strength for the serving cell. If the measurement signal strength for the serving cell is lower than SintraSearch (1f-25), the UE may perform intra-freq measurement. If the measurement signal strength for the serving cell is lower than SnonintraSearch (1f-30), the UE may perform inter-freq/RAT measurement on a frequency whose priority is the same as or lower than that of the current serving cell. The reason for triggering the UE measurement in this way is to reduce power consumption of the UE due to the neighboring cell measurement. When the channel QoS of the high-priority frequency cell (1f-10) is higher than a specific threshold ThreshX-high (1f-35), the UE may reselect the high-priority frequency cell as the serving cell. When the channel QoS of the cell (1f-00) of the frequency with low priority is higher than a specific threshold ThreshX-low (1f-15) and the QoS of the serving cell is lower than ThreshServing-low (1f-20), the terminal is low A cell of a frequency having a priority may be reselected as a serving cell.

During cell reselection, the UE may consider received signal strength (RSRP) or received signal quality (RSRQ). The received signal strength or received signal quality means a value calculated by S-criteria. That is, it may be Srxlev or Squal.

Srxlev = Q _rxlevmeas - (Q _rxlevmin + Q _{rxlevminoffset} )- P _compensation - Qoffset _temp

Squal = Q _qualmeas - (Q _qualmin + Q _{qualminoffset} ) - Qoffset _temp

where:

In particular, in the case of inter-RAT cell reselection to NR, Srxlev is used, and the Srxlev value can be compared with a specific threshold value ThreshX-high or ThreshX-low. In the present disclosure, if the LTE base station provides a q-RxLevMinSUL value for a specific NR frequency through system information and the UE supports supplementary uplink (SUL), inter-RAT cell reselection to an NR cell belonging to the NR frequency is performed. It is characterized in that the Srxlev value is derived by applying the q-RxLevMinSUL value as the Qrxlevmin value of Srxlev. A q-RxLevMinSUL value is provided for each NR frequency, and if NR cells belonging to a specific NR frequency support SUL, a q-RxLevMinSUL value for a specific NR frequency may be provided. The q-RxLevMinSUL value may not be provided for an NR frequency that does not support SUL. When using the received signal quality, that is, RSRQ, the base station may separately provide Threshserving-lowQ, ThreshX-lowQ, and ThreshX-highQ to the UE through broadcast. When using the received signal strength, Threshserving-lowP, ThreshX-lowP, and ThreshX-highP may be used.

In the present disclosure, a standby mode/inactive mode operation applied by an NR-light terminal is proposed. The NR-light terminal collectively refers to an NR terminal having limited capabilities in order to reduce complexity and manufacturing cost. In general, a machine-type communication device or an Internet Over Thing (IoT) device having a lower service requirement than a general terminal may belong to the NR-light terminal. The NR-light terminal may have the following characteristics.

- Reduced number of UE RX/TX antenna support

- Reduced UE BW support

- Half-Duplex-FDD support

- Relaxed UE processing time support

- Relaxed UE processing capability support

In addition, according to the use case of the NR-light terminal, more advanced terminal power saving technology, etc. will be applied.

An NR-light terminal and a general terminal may coexist in one wireless network, and a base station capable of supporting an NR-light terminal and a base station that cannot support the NR-light terminal may coexist in the wireless network. Therefore, the NR-light terminal should be able to inform the network that it is a terminal with limited capabilities, and the network should be able to control the access of the NR-light terminal in consideration of this.

1G is a flowchart of a process in which an NR-light terminal performs a standby mode/inactive mode operation according to an embodiment of the present disclosure.

Referring to FIG. 1G, in step 1g-05, the NR-light terminal may select a PLMN in consideration of SST (Slice/Service type) supported by each PLMN. Alternatively, the NR-light terminal may select a PLMN in consideration of whether the NR-light function is supported for each PLMN.

The SST refers to a service type having predetermined characteristics, and in addition to the standardized SST as described below, there is an SST defined by a mobile communication service provider. The SST information defined by the mobile communication service provider may be provided to the terminal at the application level.

In the present disclosure, a case in which the NR-light terminal corresponds to the MIoT SST is considered. In this case, the NR-light terminal may have an SST value of 3. In another embodiment, a separate indicator indicating NR-light may be used.

In step 1g-10, the NR-light terminal determines whether the cell provides NR-light through MIB (Master Information Block) broadcast by the cell or predetermined information provided through SIB1 to select a cell. have.

In step 1g-15, the NR-light terminal may perform establishment under SST or NR-light dedicated access control.

In step 1g-20, the NR-light terminal may perform a cell reselection operation in consideration of a frequency provided through a predetermined SIB or SST information supported by each cell.

1h is a flowchart of a process in which an NR-light terminal performs a PLMN selection operation according to an embodiment of the present disclosure.

Referring to FIG. 1H , a terminal 1h-05 may be configured with a terminal NAS 1h-10 and a terminal AS 1h-15. The NAS is in charge of processes not directly related to wireless access, namely authentication, service request, and session management, whereas the AS may be in charge of processes related to wireless access. The terminal NAS may request PLMN information of neighboring cells from the terminal AS (1h-30). The terminal AS may automatically collect PLMN information of neighboring cells when the terminal NAS requests PLMN information of neighboring cells or according to a predetermined implementation rule. Since the terminal supports the NR-light function, the terminal NAS may request only PLMN information provided from cells supporting NR-light from the terminal AS. The terminal AS may collect PLMN information and information indicating whether the NR-light function is supported from system information broadcast by a cell providing the best signal strength for each frequency. If the terminal NAS requests only the PLMN information provided from cells supporting NR-light from the terminal NAS, the terminal AS receives PLMN information and NR from the system information broadcast by cells providing the top N good signal strengths for each frequency. You can collect information indicating whether or not the -light function is supported. Since the cell providing the best signal strength may not support the NR-light function, it is necessary to receive system information from a plurality of cells for each frequency. The neighboring base station 1h-20 may broadcast PLMN information supported by it and SST information supportable for each PLMN through the system information (1h-35). In another embodiment, the base station 1h-20 may transmit by including an indicator indicating whether to support the NR-light function for each PLMN or by including a list of cells supporting the NR-light function for each PLMN. have. Upon receiving the system information, the terminal AS may transmit the following information to the terminal NAS (1h-40).

- RSRP and PLMN identity list of strongest cell

- SST list information supported for each PLMN obtained from SIB1 of the strongest cell or an indicator indicating whether NR-light is supported

- If the terminal NAS requests only the PLMN information provided from cells supporting NR-light from the terminal AS, the RSRP and PLMN identity list of the strongest cell among the cells supporting the NR-light function among the cells that have received the system information

- If the signal strength (RSRP) of the strongest cell is lower than a predetermined threshold, the RSRP value is also transmitted

The terminal NAS selects the PLMN and slice to perform the registration procedure in consideration of RAN slice info, PLMN identity list, channel status, etc., and if it is an NR-light terminal, it can select a PLMN that supports 3 SST value (1h-45) ). Alternatively, the terminal NAS may select a PLMN supporting the NR-light function.

The UE may select one suitable cell from the selected PLMN and SST (or supporting the NR-light function) (1h-50).

The terminal NAS triggers the ATTACH process (1h-55), and the terminal can perform access to the selected cell (1h-20) through the Access Control operation (1h-60) (1h-65). In this case, the selected SST information may be reported to the cell. Through the NAS container, the ATTACH message may be transmitted to the AMF (1h-25) (1h-70).

1I is a flowchart of a process in which an NR-light terminal performs an Access Control operation according to an embodiment of the present disclosure.

Referring to FIG. 1I , a network 1i-20 may transmit mapping information between an access type and an access category corresponding to SST or NR-light access to a terminal NAS 1i-10 (1i-25). The terminal AS 1-15 may receive SST or access control configuration information for an access category corresponding to the SST through system information broadcast by the network (1i-35). Alternatively, the network may broadcast access control configuration information for each PLMN and each SST.

When the NR-light access is triggered, the terminal NAS 1i-10 selects an access identity and an access category corresponding thereto (1i-30), along with the selected access identity and access category, SST information corresponding to the NR-light can be transmitted to the terminal AS (1i-15) (1i-40). The terminal AS 1i-15 may perform a barring check operation by applying access control parameters corresponding to the access identity, access category, and SST information provided from the terminal NAS 1i-10 (1i-45). If the access control parameter for the selected SST of the selected PLMN exists, the terminal AS 1i-15 performs a barring check operation by applying the corresponding parameter, but if there is no access control parameter for the selected SST of the selected PLMN, a barring check operation is performed using the conventional access category for each PLMN. can do. If access is allowed through the barring check operation, the terminal 1i-05 may perform an establishment or resume operation on the network 1i-20 (1i-50).

1J is a flowchart of a process in which an NR-light terminal performs a cell reselection operation according to an embodiment of the present disclosure.

Referring to FIG. 1J , a terminal 1j-05 may obtain system information from a base station 1j-10 (1j-15). The terminal 1j-05 may acquire supportable SST information of intra-frequency neighboring cells from SIB3 and supportable SST information of inter-frequency neighboring cells from SIB4 among the system information. For example, a plurality of information sets composed of [NR frequency, supported SST] may be included in the system information. The terminal 1j-05 may measure a serving frequency and an adjacent frequency for cell reselection. At this time, the terminal 1j-05 considers the frequency and neighboring cells supporting SST corresponding to NR-light as cell reselection candidates (or adjusting the cell reselection priority of the NR frequency that does not support the selected SST to the lowest priority) and can periodically perform measurement and compare with the serving cell (1j-20). For cell reselection, the terminal 1j-05 may perform reselection on a cell that satisfies the following three conditions among the highest ranked cells.

- Target cell marked as supporting Selected SST in SIB3, SIB4 of the current serving cell

- The UE supports Sub-Carrier Spacing (SCS) indicated in subCarrierSpacingCommon of the MIB of the target cell.

- Target cell marked as supporting Selected SST in SIB1 of target cell

The SIB3, SIB4, and RRCRelease messages may include an indicator indicating whether to support the NR-light function for each frequency, or list information of cells supporting the NR-light function for each frequency. If the terminal is an NR-light terminal, the frequency that does not support the NR-light function according to the corresponding indicator is regarded as the frequency with the lowest priority regardless of the cell reselection priority, or cells belonging to the corresponding frequency are cell reselection It is not considered a suitable cell capable of

1K is a block diagram illustrating an internal structure of a terminal according to an embodiment of the present disclosure.

Referring to FIG. 1K , the terminal may include a radio frequency (RF) processing unit 1k-10, a baseband processing unit 1k-20, a storage unit 1k-30, and a control unit 1k-40. have. Of course, it is not limited to the above example, and the terminal may include fewer or more configurations than the configuration shown in FIG. 1H .

The RF processing unit 1k-10 performs a function for transmitting and receiving a signal through a wireless channel, such as band conversion and amplification of the signal. That is, the RF processing unit 1k-10 up-converts the baseband signal provided from the baseband processing unit 1k-20 into an RF band signal, transmits it through the antenna, and converts the RF band signal received through the antenna to the baseband. can be down-converted to a signal. For example, the RF processing unit 1k-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), and the like. have. In the drawing, only one antenna is shown, but the terminal may include a plurality of antennas. Also, the RF processing unit 1k-10 may include a plurality of RF chains. Furthermore, the RF processing unit 1k-10 may perform beamforming. For beamforming, the RF processing unit 1k-10 may adjust the phase and magnitude of each of signals transmitted and received through a plurality of antennas or antenna elements. In addition, the RF processing unit 1k-10 may perform MIMO (Multi Input Multi Output), and may receive multiple layers when performing the MIMO operation.

The baseband processing unit 1k-20 may perform a function of converting between a baseband signal and a bit stream according to a physical layer standard of a system. For example, when transmitting data, the baseband processing unit 1k-20 may generate complex symbols by encoding and modulating the transmitted bit stream. Also, upon data reception, the baseband processing unit 1k-20 may restore the received bit stream by demodulating and decoding the baseband signal provided from the RF processing unit 1k-10. For example, in the case of orthogonal frequency division multiplexing (OFDM), when transmitting data, the baseband processing unit 1k-20 encodes and modulates a transmission bit stream to generate complex symbols, and maps the complex symbols to subcarriers. After that, OFDM symbols can be configured through inverse fast Fourier transform (IFFT) operation and cyclic prefix (CP) insertion. In addition, upon data reception, the baseband processing unit 1k-20 divides the baseband signal provided from the RF processing unit 1k-10 into OFDM symbol units, and is mapped to subcarriers through a fast Fourier transform (FFT) operation. After reconstructing the signals, the received bit stream may be reconstructed through demodulation and decoding.

The baseband processing unit 1k-20 and the RF processing unit 1k-10 may transmit and receive signals as described above. Accordingly, the baseband processing unit 1k-20 and the RF processing unit 1k-10 may be referred to as a transmitter, a receiver, a transceiver, or a communication unit. Furthermore, at least one of the baseband processing unit 1k-20 and the RF processing unit 1k-10 may include a plurality of communication modules to support a plurality of different wireless access technologies. In addition, at least one of the baseband processing unit 1k-20 and the RF processing unit 1k-10 may include different communication modules to process signals of different frequency bands. For example, different wireless access technologies may include a wireless LAN (eg, IEEE 802.11), a cellular network (eg, LTE), and the like. In addition, the different frequency bands may include a super high frequency (SHF) (eg, 2.NRHz, NRhz) band and a millimeter wave (eg, 60GHz) band. The terminal may transmit/receive signals to and from the base station using the baseband processing unit 1k-20 and the RF processing unit 1k-10, and the signals may include control information and data.

The storage unit 1k-30 may store data such as a basic program, an application program, and setting information for the operation of the terminal. In particular, the storage unit 1k-30 may store information related to a second access node that performs wireless communication using a second wireless access technology. In addition, the storage unit 1k-30 may provide stored data according to the request of the control unit 1k-40. The storage unit 1k-30 may be configured of a storage medium such as a ROM, a RAM, a hard disk, a CD-ROM, and a DVD, or a combination of storage media. Also, the storage unit 1k-30 may include a plurality of memories. According to an embodiment of the present disclosure, the storage unit 1k-30 may store a program for performing the method of providing IDC information according to the present disclosure.

The controller 1k-40 may control overall operations of the terminal. For example, the control unit 1k-40 may transmit/receive signals through the baseband processing unit 1k-20 and the RF processing unit 1k-10. In addition, the control unit 1k-40 may write and read data in the storage unit 1k-40. To this end, the controller 1k-40 may include at least one processor. For example, the controller 1k-40 may include a communication processor (CP) that controls for communication and an application processor (AP) that controls an upper layer such as an application program. Also, according to an embodiment of the present disclosure, the controller 1k-40 may include a multi-connection processing unit 1k-42 configured to process a process operating in a multi-connection mode. In addition, at least one component in the terminal may be implemented as one chip.

11 is a block diagram illustrating a configuration of a base station according to an embodiment of the present disclosure.

Referring to FIG. 11, the base station may include an RF processing unit 11-10, a baseband processing unit 11-20, a backhaul communication unit 11-30, a storage unit 11-40, and a control unit 11-50. can Of course, it is not limited to the above example, and the base station may include fewer or more configurations than the configuration shown in FIG. 11 .

The RF processing unit 11-10 may perform a function for transmitting and receiving a signal through a wireless channel, such as band conversion and amplification of the signal. That is, the RF processing unit 11-10 up-converts the baseband signal provided from the baseband processing unit 11-20 into an RF band signal, transmits it through the antenna, and converts the RF band signal received through the antenna to the baseband. It can be downconverted to a signal. For example, the RF processing unit 11-10 may include a transmit filter, a receive filter, an amplifier, a mixer, an oscillator, a DAC, an ADC, and the like. In FIG. 11, only one antenna is shown, but the RF processing unit 11-10 may include a plurality of antennas. Also, the RF processing unit 11-10 may include a plurality of RF chains. Furthermore, the RF processing unit 11-10 may perform beamforming. For beamforming, the RF processing unit 11-10 may adjust the phase and magnitude of each of signals transmitted and received through a plurality of antennas or antenna elements. The RF processing unit 11-10 may perform a downlink MIMO operation by transmitting one or more layers.

The baseband processing unit 11-20 may perform a conversion function between a baseband signal and a bit stream according to the physical layer standard of the first radio access technology. For example, when transmitting data, the baseband processing unit 11-20 may generate complex symbols by encoding and modulating the transmitted bit stream. Also, upon data reception, the baseband processing unit 11-20 may restore the received bit stream by demodulating and decoding the baseband signal provided from the RF processing unit 11-10. For example, in the OFDM scheme, when data is transmitted, the baseband processing unit 11-20 generates complex symbols by encoding and modulating the transmission bit stream, maps the complex symbols to subcarriers, and performs IFFT operation and OFDM symbols can be configured through CP insertion. Also, upon data reception, the baseband processing unit 11-20 divides the baseband signal provided from the RF processing unit 11-10 into OFDM symbol units, and restores signals mapped to subcarriers through FFT operation. , it is possible to restore the received bit stream through demodulation and decoding. The baseband processing unit 11-20 and the RF processing unit 11-10 may transmit and receive signals as described above. Accordingly, the baseband processing unit 11-20 and the RF processing unit 11-10 may be referred to as a transmitter, a receiver, a transceiver, a communication unit, or a wireless communication unit. The base station may transmit/receive a signal to/from the terminal using the baseband processing unit 11-20 and the RF processing unit 11-10, and the signal may include control information and data.

The backhaul communication unit 11-30 may provide an interface for performing communication with other nodes in the network. That is, the backhaul communication unit 11-30 converts a bit string transmitted from the main base station to another node, for example, an auxiliary base station, a core network, etc. into a physical signal, and converts a physical signal received from another node into a bit string can do.

The storage unit 11-40 stores data such as a basic program, an application program, and setting information for the operation of the base station. In particular, the storage unit 11-40 may store information on a bearer allocated to an accessed terminal, a measurement result reported from the accessed terminal, and the like. In addition, the storage unit 11-40 may store information serving as a criterion for determining whether to provide or stop multiple connections to the terminal. In addition, the storage unit 11-40 may provide stored data according to a request of the control unit 11-50. The storage unit 11-40 may be configured of a storage medium such as a ROM, a RAM, a hard disk, a CD-ROM, and a DVD, or a combination of storage media. Also, the storage unit 1h-40 may include a plurality of memories.

The control unit 11-50 controls overall operations of the main station. For example, the control unit 11-50 may transmit/receive a signal through the baseband processing unit 11-20 and the RF processing unit 11-10 or through the backhaul communication unit 11-30. Also, the control unit 11-50 may write data to and read data from the storage unit 11-40. To this end, the controller 11-50 may include at least one processor. Also, according to an embodiment of the present disclosure, the controller 11-50 may include a multi-connection processing unit 11-52 configured to process a process operating in a multi-connection mode.

Methods according to the embodiments described in the claims or specifications of the present disclosure may be implemented in the form of hardware, software, or a combination of hardware and software.

When implemented in software, a computer-readable storage medium storing one or more programs (software modules) may be provided. One or more programs stored in the computer-readable storage medium are configured to be executable by one or more processors in an electronic device (device). One or more programs include instructions for causing an electronic device to execute methods according to embodiments described in a claim or specification of the present disclosure.

Such programs (software modules, software) include random access memory, non-volatile memory including flash memory, read only memory (ROM), electrically erasable programmable ROM (EEPROM: Electrically Erasable Programmable Read Only Memory), magnetic disc storage device, Compact Disc-ROM (CD-ROM), Digital Versatile Discs (DVDs), or any other form of It may be stored in an optical storage device or a magnetic cassette. Alternatively, it may be stored in a memory composed of a combination of some or all thereof. In addition, each configuration memory may be included in plurality.

In addition, the program is transmitted through a communication network consisting of a communication network such as the Internet, Intranet, Local Area Network (LAN), Wide LAN (WLAN), or Storage Area Network (SAN), or a combination thereof. It may be stored on an attachable storage device that can be accessed. Such a storage device may be connected to a device implementing an embodiment of the present disclosure through an external port. In addition, a separate storage device on the communication network may be connected to the device implementing the embodiment of the present disclosure.

In the specific embodiments of the present disclosure described above, components included in the disclosure are expressed in the singular or plural according to the specific embodiments presented. However, the singular or plural expression is appropriately selected for the context presented for convenience of description, and the present disclosure is not limited to the singular or plural component, and even if the component is expressed in plural, it is composed of a singular or singular. Even an expressed component may be composed of a plurality of components.

Meanwhile, although specific embodiments have been described in the detailed description of the present disclosure, various modifications are possible without departing from the scope of the present disclosure. Therefore, the scope of the present invention should not be limited to the described embodiments and should be defined by the claims described below as well as the claims and equivalents. That is, it will be apparent to those of ordinary skill in the art to which the present disclosure pertains that other modifications may be implemented based on the technical spirit of the present disclosure. In addition, each of the above embodiments may be operated in combination with each other as needed. For example, a base station and a terminal may be operated by combining parts of the methods proposed in the present disclosure. In addition, although the above embodiments have been presented based on 5G and NR systems, other modifications based on the technical idea of the embodiments may be implemented in other systems such as LTE, LTE-A, and LTE-A-Pro systems.

Claims (1)

A method of operating a terminal in a wireless communication system, the method comprising:
Receiving a request for collection of PLMN information from the NAS (Non-Access Stratum) of the terminal in the AS (Access Stratum) of the terminal;
scanning all carriers within a frequency band supportable by the AS based on the received request from the AS of the terminal;
identifying a cell providing a signal of a maximum size based on the scan result in the AS of the terminal;
obtaining PLMN information of the cell from system information of a cell providing the identified maximum signal in the AS of the terminal; and
Comprising the step of reporting the acquired PLMN information of the cell to the NAS of the terminal in the AS of the terminal, the method.

Images