Method and apparatus for processing paging and system information (SI) of a multi-universal subscriber identity module (MUSIM) user equipment (UE)

Abstract

Provided is a communication method and system for integrating a fifth generation (5G) communication system supporting a higher data rate than a fourth generation (4G) system with Internet of Things (IoT) technology. The communication method and system can be applied to smart services based on 5G communication technology and IoT-related technologies, such as smart homes, smart buildings, smart cities, smart cars, Internet of Vehicles, healthcare, digital education, smart retail, security and safety services. Provided is a method performed by a terminal in a wireless communication system.

Description

Technical Field

[0001] The present disclosure relates to systems and methods for handling paging and system information (SI) of a Multi-Universal Subscriber Identity Module (MUSIM) User Equipment (UE). Background Art

[0002] In order to meet the increasing demand for wireless data services since the deployment of the 4th generation (4G) communication system, efforts have been made to develop improved 5th generation (5G) or pre-5G communication systems. Therefore, 5G or pre-5G communication systems are also called "super 4G networks" or "post-Long Term Evolution (LTE) systems". 5G wireless communication systems are considered to be deployed not only in lower frequency bands (such as the 500 MHz to 10 GHz band) but also in higher frequency (millimeter wave) bands (such as the 10 GHz to 100 GHz band) to achieve higher data rates. In order to reduce the propagation loss of radio waves and increase the transmission distance, beamforming, massive multiple-input multiple-output (MIMO), full-dimensional MIMO (FD-MIMO), array antennas, analog beamforming and massive antenna technology are being considered in the design of 5G wireless communication systems. Furthermore, in the 5G communication system, improvements in the system network are being made based on advanced small cells, cloud radio access networks (RAN), ultra-dense networks, device-to-device (D2D) communication, wireless backhaul, mobile networks, cooperative communications, coordinated multi-point (CoMP), receiving-end interference elimination, etc. In the 5G system, frequency and quadrature amplitude modulation (FQAM) (which is a combination of hybrid frequency shift keying (FSK) and quadrature amplitude modulation (QAM)) and sliding window superposition coding (SWSC) as advanced coding modulation (ACM) have been developed, as well as filter bank multi-carrier (FBMC), non-orthogonal multiple access (NOMA), and sparse code multiple access (SCMA) as advanced access technologies.

[0003] In a similar vein, the Internet, which is a human-centered connected network in which humans generate and consume information, is now evolving toward the Internet of Things (IoT), in which distributed entities (such as things) can exchange and process information without human intervention. The Internet of Everything (IoE), in which IoT technology is combined with big data processing technology by connecting cloud servers, has also emerged. 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 studied recently. Such an IoT environment can provide intelligent Internet technology services that create new value for human life by collecting and analyzing data generated between connected things. In this case, IoT can be applied to various fields such as smart homes, smart buildings, smart cities, smart cars or connected cars, smart grids, healthcare, smart home appliances and advanced medical services through the integration and combination of existing information technology (IT) and various industrial applications.

[0004] Over the past few decades, a variety of broadband wireless technologies have been developed to meet the growing number of broadband users and provide more and better applications and services such as the aforementioned. The second generation (2G) wireless communication system has been developed to provide voice services while ensuring user mobility. The third generation (3G) wireless communication system supports voice services and data services. 4G wireless communication systems have been developed to provide high-speed data services. However, the current 4G wireless communication system resources are insufficient to meet the growing demand for high-speed data services. Therefore, 5G wireless communication systems are being developed to meet the growing demand for services with different needs (such as high-speed data services) and support ultra-reliable low-latency applications.

[0005] In addition, the 5G wireless communication system is expected to address different use cases with different requirements in terms of data rate, latency, reliability, mobility, etc. However, the air interface design of the 5G wireless communication system will be flexible enough to serve user equipment (UE) with completely different capabilities, depending on the use case and market segment that the UE provides services to the end customer. Example use cases that the 5G wireless communication system is expected to address include enhanced mobile broadband (eMBB), massive machine type communication (m-MTC), ultra-reliable low latency communication (URLL), etc. The eMBB requirements (e.g., data rates like tens of Gbps, low latency, high mobility, etc.) address the market segment representing wireless broadband users who need Internet connection anytime and anywhere. The m-MTC requirements (e.g., very high connection density, infrequent data transmission, very long battery life, low mobility address, etc.) address the market segment representing IoT / IoE where billions of devices are expected to be connected. The URLL requirements (e.g., very low latency, very high reliability variable mobility, etc.) address the market segment representing industrial automation applications and vehicle-to-vehicle / vehicle-to-infrastructure communication, which is foreseen as one of the enablers of driverless cars.

[0006] In 4G wireless communication systems like LTE, there are devices with multi-universal subscriber identity module (MUSIM) capabilities, especially the proliferation of dual SIM devices in the past decade. The operation of dual SIM devices is transparent to the network, and certain processes such as paging monitoring and response paging, measurement, system information (SI) acquisition, etc. are currently handled in an implementation-specific manner. In other words, there is no standard support for effectively handling the above processes. This not only leads to a degradation in user experience in terms of data throughput loss, but also wastes network resources. Dual SIM devices have different radio frequency transmit-receive (RF Tx / Rx) capabilities, and the implementation-specific schemes for handling the above processes are not the same, but depend on the RF capabilities of the dual SIM devices. Depending on the RF Tx / Rx capabilities, the following types of dual SIM card devices are available: a) dual SIM dual standby (DSDS) with single Tx / Rx RF capabilities, b) dual SIM dual reception (DSDR) with single Tx and dual Rx RF capabilities, and c) dual SIM dual activity (DSDA) with dual Tx / Rx RF capabilities.

[0007] The terms dual SIM and MUSIM UE or device are used interchangeably throughout the disclosure. Dual SIM devices are required to monitor paging opportunities and other time-critical opportunities on each system (network) associated with each USIM, other time-building situations such as basic system information blocks (SIBs), cell broadcast information, multimedia broadcast multicast services (MBMS), etc. Typically, the system with each USIM decides these situations independently. The paging or SI opportunity of one USIM may conflict with the paging and other time-critical opportunities of other USIMs. Since there is no standard mechanism designed for MUSIM UEs from the perspective of the third generation partnership project (3GPP) standardization, these conflicts are handled in a specific manner according to the UE implementation. Therefore, this may sometimes result in lost paging or time-critical opportunities for handling paging conflicts for MUSIM devices. Recently, discussions have been held in 3GPP standardization to specify a pusher to handle the above process regardless of the RF capabilities of the UE. This will apply to LTE systems connected to the evolved packet core (EPC) and new radio (NR) systems connected to the 5G core (5GC). For example, the UE may support dual SIM card capabilities associated with Global System for Mobile Communications (GSM)+GSM, GSM+LTE, LTE+LTE, LTE+Voice over LTE (VoLTE), VoLTE+VoLTE, VoLTE+NR, LTE+NR, NR+NR, etc.

[0008] The above information is presented as background information only and is helpful for understanding the present disclosure. No determination has been made and no assertion is made as to whether any of the above may be applicable as prior art to the present disclosure. Summary of the invention

[0009] Technical issues

[0010] The main purpose of the embodiments of this document is to disclose a method and system for effectively processing paging procedures and system information (SI) acquisition by a dual user identity module (SIM) / multi-universal SIM (MUSIM) device without considering the transmit-receive (Tx / Rx) capability. This applies when the device is registered on the Evolved Packet Core (EPC) through two SIMs, registered on the 5th Generation Core (5GC) through two SIMs, or registered on the EPC through one SIM and registered on the 5GC through another SIM. Typically, two SIMs are used to register on the same system (e.g., Global System for Mobile Communications (GSM), Code Division Multiple Access (CDMA), Long Term Evolution (LTE), New Radio (NR), or any other Radio Access Technology (RAT)) or different SIMs are used to register on different systems. The embodiments of the present disclosure use dual SIMs as an example for illustration, but can be further extended to multiple SIMs.

[0011] The present disclosure aims to solve at least the above problems and / or disadvantages and provide at least the following advantages. Therefore, the present disclosure provides a communication method and system for a 5G communication system that integrates support for higher data rates than the fourth generation (4G) system.

[0012] Technical Solution

[0013] Additional aspects will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the presented embodiments.

[0014] According to one aspect of the present disclosure, a method performed by a terminal in a wireless communication system is provided. The method includes: when the terminal has at least two user identity modules (SIM) capabilities, monitoring a system information (SI) update indication in at least one first paging occasion (occasion) of at least one modification period (period) of a first network associated with a first SIM, and when the terminal fails to monitor at least one first paging occasion, monitoring the SI update indication in at least one second paging occasion, determining whether any SI is updated according to the SI update indication; and when any SI is updated, acquiring the updated SI.

[0015] According to another aspect of the present disclosure, a terminal in a wireless communication system is provided. The terminal includes a transceiver and at least one processor operably coupled to the transceiver. The at least one processor is configured to: monitor a system information (SI) update indication in at least one first paging occasion of at least one modification period of a first network associated with a first SIM when the terminal has at least two SIM capabilities; monitor the SI update indication in at least one second paging occasion when the at least one processor fails to monitor at least one first paging occasion, and determine whether any SI is updated according to the SI update indication; and obtain the updated SI when any SI is updated.

[0016] Beneficial technical effects

[0017] The present disclosure provides various methods and systems for efficiently processing paging transmission / reception and system information (SI) acquisition by a dual subscriber identity module (SIM) / multi-universal SIM (MUSIM) device regardless of transmission / reception (Tx / Rx) capabilities.

[0018] Other aspects, advantages, and salient features of the disclosure will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the accompanying drawings, discloses various embodiments of the disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The above and other aspects, features and advantages of certain embodiments of the present disclosure will become more apparent from the following description in conjunction with the accompanying drawings, in which:

[0020] Figure 1 It shows a problem that the user equipment (UE) does not have the latest version of SI used in network A and affects its operation in network A;

[0021] Figure 2 The operation of the UE according to the embodiment of the present disclosure is shown;

[0022] Figure 3 is an example illustration of operations according to suggestions based on embodiments of the present disclosure;

[0023] Figure 4 The problem of delayed paging is shown;

[0024] Figure 5 is an example illustration of a method according to an embodiment of the present disclosure;

[0025] Figure 6 is an example illustration of a method according to an embodiment of the present disclosure;

[0026] Figure 7 is a block diagram of a terminal according to an embodiment of the present invention; and

[0027] Figure 8 is a block diagram of a base station according to an embodiment of the present disclosure.

[0028] Throughout the drawings, like reference numerals will be understood to refer to like parts, components, and structures. DETAILED DESCRIPTION

[0029] Discussed below Figures 1 to 8 The various embodiments used to describe the principles of the present disclosure in this patent document are for illustration only and should not be interpreted in any way as limiting the scope of the present disclosure. Those skilled in the art will appreciate that the principles of the present disclosure can be implemented in any appropriately arranged system or device.

[0030] 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 as defined by the claims and their equivalents. It includes various specific details to assist in understanding, but these are to be considered as exemplary only. Therefore, it will be appreciated by those of ordinary skill in the art that various changes and modifications may 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 configurations may be omitted for clarity and brevity.

[0031] The terms and words used in the following description and claims are not limited to the literal meanings, but are merely used by the inventor to enable a clear and consistent understanding of the present disclosure. Therefore, it should be clear to those skilled in the art that the following description of various embodiments of the present disclosure is provided for illustration purposes rather than for the purpose of limiting the present disclosure as defined by the appended claims and their equivalents.

[0032] It should be understood that the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to "a component surface" includes reference to one or more of such surfaces.

[0033] The term "substantially" means that the features, parameters or values ​​described need not be achieved precisely, but may deviate or vary by an amount that does not affect the effect that the feature is intended to provide (including, for example, tolerances, measurement errors, measurement precision limitations and other factors known to those skilled in the art).

[0034] It is known to those skilled in the art that the blocks of a flowchart (or sequence diagram) and the combination of the flowchart can be represented and executed by computer program instructions. These computer program instructions can be loaded onto a processor of a general-purpose computer, a special-purpose computer, or a programmable data processing device. When the loaded program instructions are executed by the processor, they create a way to perform the functions described in the flowchart. Because the computer program instructions can be stored in a computer-readable memory that can be used for a special-purpose computer or a programmable data processing device, an article that performs the functions described in the flowchart can also be created. Since the computer program instructions can be loaded onto a computer or a programmable data processing device, when executed as a process, they can perform the operations of the functions described in the flowchart.

[0035] The blocks of the flowchart may correspond to a module, segment or code containing one or more executable instructions to implement one or more logical functions, or may correspond to a portion thereof. In some cases, the functions described by the blocks may be performed in a different order than the order listed. For example, two blocks listed in sequence may be executed simultaneously or in reverse order.

[0036] In this specification, the words "unit", "module", etc. may refer to software components or hardware components, such as, for example, a field programmable gate array (FPGA) or an application specific integrated circuit (ASIC) capable of performing a function or operation. However, "unit", etc. are not limited to hardware or software. Units, etc. may be configured to reside in an addressable storage medium or drive one or more processors. Units, etc. may also refer to software components, object-oriented software components, class components, task components, processes, functions, attributes, procedures, subroutines, program code segments, drivers, firmware, microcodes, circuits, data, databases, data structures, tables, arrays, or variables. The functions provided by a component and unit may be a combination of smaller components and units, or may be combined with other components and units to form larger components and units. Components and units may be configured to drive devices or one or more processors in a secure multimedia card.

[0037] Before the detailed description, terms or definitions necessary for understanding the present disclosure are described. However, these terms should be interpreted in a non-limiting manner.

[0038] A base station (BS) is an entity that communicates with a user equipment (UE) and may be referred to as a BS, a base transceiver station (BTS), a node B (NB), an evolved NB (eNB), an access point (AP), a fifth generation (5G) NB (5GNB), or a next generation NB (gNB).

[0039] The UE is an entity that communicates with the BS and may be referred to as a UE, a device, a mobile station (MS), a mobile equipment (ME), or a terminal.

[0040] System information

[0041] In a wireless communication system, a Node B (gNB) or base station in a cell broadcasts system information (SI). SI includes common parameters required for communication in the cell. In a 5G wireless communication system (also known as Next Generation Radio or NR), SI is divided into a master information block (MIB) and multiple system information blocks (SIBs), where:

[0042] The MIB is always sent on the Broadcast Channel (BCH) (or Physical BCH (PBCH)) with a period of 80 ms and repeated within 80 ms, and it includes the parameters required to obtain SIB1 from the cell.

[0043] SIB1 is sent on the downlink shared channel (DL-SCH) with a period of 160ms and the transmission repetition time is variable. The default transmission repetition period of SIB1 is 20ms, but the actual transmission repetition period is determined by the network implementation. SIB1 includes information about the availability and scheduling of other SIBs (e.g., mapping of SIBs to SI messages, periodicity, SI window size), SIB1 has an indication of whether one or more SI messages are being broadcast, and in the case where no SI message is being broadcast, SIB1 includes the configuration required for the UE to perform the SI request. SIB1 is a cell-specific SIB;

[0044] SIBs other than SIB1 are carried in SystemInformation (SI) messages, which are transmitted on DL-SCH. Only SIBs with the same period can be mapped to the same SI message. Each SI message is transmitted within a time domain window that occurs periodically (called an SI window with the same length for all SI messages). Each SI message is associated with an SI window, and the SI windows of different SI messages do not overlap. That is, within an SI window, only the corresponding SI message is sent. In the SI window, the UE monitors the physical downlink control channel (PDCCH) monitoring timing (i.e., symbol / time slot) configured for SI message reception. For SI message acquisition, the PDCCH monitoring timing is determined according to osi-searchSpace. If osi-searchSpace is set to zero (also called the default association), the PDCCH monitoring timing for SI message reception in the SI-Window is the same as the PDCCH monitoring timing for SIB1. If osi-searchSpace is not set to zero (also called the non-default association), the PDCCH monitoring timing for the SI message is determined according to the search space indicated by osi-searchSpace.

[0045] In 5G (also known as NR or New Radio) wireless communication systems, the receive and transmit bandwidth of a UE does not need to be as large as the bandwidth of a cell and can be adjusted: the width can be commanded to vary (e.g., shrink during low activity to save power); the location can be moved in the frequency domain (e.g., to increase scheduling flexibility); and the subcarrier spacing can be commanded to vary (e.g., to allow different services). A subset of the total cell bandwidth of a cell is called a BandWidth Part (BWP). In the Radio Resource Control (RRC) Connected (CONNECTED) state, for each configured serving cell (i.e., primary cell (PCell) or secondary cell (SCell)), the UE is configured with one or more DL and uplink (UL) BWPs. For an activated serving cell, there is always one active UL and DL BWP at any point in time. BWP switching of a serving cell is used to activate one inactive BWP and disable one active BWP at a time. Initiation of BWP switching during the random access procedure is controlled by a PDCCH indicating a DL assignment or UL grant, by a bwp-InactivityTimer, by RRC signaling, or by the Medium Access Control (MAC) entity itself. When a special cell (SpCell) is added or an SCell is activated, the DLBWP and ULBWP indicated by firstActiveDownlinkBWP-Id and firstActiveUplinkBWP-Id, respectively, are active without receiving a PDCCH indicating a DL allocation or UL grant. The active BWP of the serving cell is indicated by RRC or PDCCH. For unpaired spectrum, the DL BWP is paired with the ULBWP, and BWP switching is common for both UL and DL. When the BWP inactivity timer expires, the UE switches the active DLBWP to the default DL BWP or the initial DL BWP (if no default DL BWP is configured).

[0046] In the frequency domain, the bandwidth (or control resource set (CORESET)) used for SI message and paging reception is the initial DL BWP of the UE in RRC IDLE state and RRC INACTIVE state. The initial DL BWP parameters are configured by the MIB. The bandwidth (or CORESET) for SI message and paging reception is the active DL BWP of the UE in RRC connected state. In the RRC connected state, if osi-searchSpace is not sent for the active DL BWP, SI is not broadcast in the active DL BWP.

[0047] The SI broadcast in the cell can be updated. To update the SI, the concept of a modification period is used. Using a modification period, the updated SI (except for Earthquake and Tsunami Warning System (ETWS) and Commercial Mobile Alert System (CMAS)) is broadcast in a modification period after the modification period in which the SI change indication is sent. If the gNB sends an SI change indication in modification period N, the updated SI is broadcast from modification period N+1. The modification period boundary is defined by the system frame number (SFN) value, where SFN mod m=0, where m is the number of radio frames containing the modification period. The modification period is configured by the SI. The UE receives indications about SI modifications and / or public warning system (PWS) notifications using a short message (ShortMessage) transmitted using a paging radio network temporary identifier (P-RNTI) via DL control information (DCI). Within the modification period, the SI change indication and / or PWS notification can be repeated multiple times. Each modification period is a multiple of the default discontinuous reception (DRX) cycle period (cycle). The length of the default DRX cycle period is broadcast by the gNB in ​​the SI (i.e. in SIB1). The SI change indication and / or PWS notification is sent in each paging occasion (PO) of the default DRX cycle period so that each UE can receive the SI change indication and / or PWS notification. Note that there can be multiple POs in one DRX cycle period, and the UE determines the PO to monitor based on its UE identifier (ID).

[0048] A UE in RRC Idle or RRC Inactive state monitors SI change indications in its own PO in every DRX cycle period. If a common search space is provided to the UE to monitor paging in the active DL BWP, the UE in the RRC connection monitors SI change indications in any PO at least once in each modification period. A UE with ETWS or CMAS capability in RRC Idle or RRC Inactive state monitors indications about PWS notifications in its own PO in every DRX cycle period. If a common search space is provided to the UE to monitor paging in the active DL BWP, the UE with ETWS or CMAS capability in the RRC connection monitors indications about PWS notifications in any PO at least once in every default DRX cycle period (also called default paging cycle period).

[0049] Problem: In case of MUSIM UE, due to the lack of available radio frequency (RF) to monitor network A, the UE may miss monitoring SI update indication during the modification period of network A. As a result, the UE does not have the latest version of SI used in network A and affects its operation in network A. This problem is solved using Figure 1 Further explanation was given. Figure 1(a) shows the default DRX cycle period (T-default), the modification period and the PO configured in a cell of network A, where the cell is the serving / camping cell of the UE. The value of modifyPeriodCoeff is equal to 2, which results in the modification period consisting of two DRX cycle periods. Figure 1 (b) shows the DRX cycle period of the UE and the PO in which the UE monitors to receive paging and SI update indications. Figure 1 (c) shows the time interval during which the RF is not available for monitoring network A because the UE may be monitoring a call on network B or performing other tasks. Figure 1 In the scenario shown, the UE cannot monitor any of its POs during the modification period. Therefore, if network A sends an SI update indication during the modification period, the UE and network A will be out of sync with respect to SI.

[0050] In order to solve the above problem, in the embodiment of the present invention, the UE performs the following Figure 2 The operations are shown. In RRC Idle or RRC Inactive state:

[0051] If the UE has dual SIM dual standby (DSDS) capability (or the UE is a MUSIM UE that cannot monitor networks associated with multiple SIMs simultaneously, or the UE does not have a dedicated RF to monitor the SI of the network), the UE monitors the SI change indication in any PO every modification period in operation 210. In other words, the UE monitors the short message in the PDCCH addressed to the Paging Radio Network Temporary Identifier (P-RNTI) in any PO every modification period. In an embodiment, the UE monitors paging in its PO every DRX cycle period. In another embodiment, the UE monitors paging in any PO every modification period.

[0052] If the UE fails to monitor any PO in the modification period (eg due to RF unavailability, ie busy monitoring another network), the UE reacquires the MIB and reacquires SIB1 to determine if any SI is updated in operation 220. The UE then reacquires the updated SI (if any).

[0053] If the UE does not monitor any PO for 'N' consecutive modification periods, the UE re-acquires the MIB and re-acquires SIB1 to determine whether any SI is updated. The UE then re-acquires the updated SI (if any). The value of 'N' can be pre-defined or signaled by the network (e.g., base station, NB, gNB) in the SI.

[0054] Otherwise, in operation 230, the UE monitors the SI change indication in its PO every DRX cycle period. The UE monitors the paging in its PO every DRX cycle period. The UE selects a PO from multiple POs in one DRX cycle period based on its UE ID.

[0055] In RRC Idle / Inactive state, if the UE is unable to monitor its PO during the modification period of the network associated with SIM1 due to monitoring other SIM2, the UE may do one of the following:

[0056] Option 1: The UE may monitor the SI update indication in other POs during the modification period of the network associated with SIM1, as long as it does not overlap with the monitoring of other SIM2. In other words, the UE may monitor the SI update indication in any PO (not just its PO) during the modification period, as long as it does not overlap with its other RAT / SIM monitoring.

[0057] Option 2: If the UE fails to monitor the SI update indication during the modification period of the network associated with SIM1 due to monitoring SIM2, then after resuming monitoring of the network associated with SIM1, the UE first reads the MIB and SIB1 to determine whether any SI is updated. The UE then reacquires the updated SI (if any). In other words, if the UE fails to monitor the SI update indication during the modification period due to other RAT / SIM monitoring, then when resuming monitoring of the RAT, the UE reads the MIB and SIB1 to determine whether any SI is updated.

[0058] Option 3: If the SI update indication fails to be monitored in its PO, Option 2 may be applied.

[0059] Option 4: If no SI update indication is monitored in any PO during the modification period, option 2 may be applied.

[0060] Figure 3 is an example illustration of a suggested operation according to an embodiment of the present disclosure. Figure 3 (a) and (b), there are 4 POs during the modification period. Figure 3 (b), the PO determined by the paging / SI update monitoring based on the UE ID is the first PO and the third PO. Figure 3 As shown in (c), the RF is not available to monitor these POs, so the UE monitors the 4th PO in the modification period even though it is not the UE's PO.

[0061] Paging

[0062] In a wireless communication system, paging is sent to a paging UE that is attached to a wireless communication network but is in idle / inactive mode. In idle / inactive mode, the UE wakes up in a short time at a fixed interval (i.e., each paging DRX cycle period) to receive paging messages, short messages and other broadcast information. The network can configure multiple POs in one DRX cycle period. In one PO, a PDCCH addressed to the P-RNTI is sent. The DCI of the PDCCH addressed to the P-RNTI includes a short message and / or scheduling information for the paging message. The paging message is sent using the physical downlink shared channel (PDSCH). The short message indication field in the DCI of the PDCCH addressed to the P-RNTI indicates whether there is only scheduling information for paging in the DCI or only short messages in the DCI, or both scheduling information for paging and short messages in the DCI. The short message includes the SystemInfoModification bit and the etwsAndCmasIndication bit. The SystemInfoModification bit set to 1 indicates an SI update other than SIB6, SIB7, and SIB8. The etwsAndCmasIndication bit set to 1 indicates an ETWS primary notification and / or an ETWS secondary notification and / or a CMAS notification. The P-RNTI is common to all UEs. Therefore, the UE identity is included in the paging message to indicate paging for a specific UE. In the case of a core network (CN) paging a UE, the paging UE identity is the System Architecture Evolution (SAE)-Temporary Mobile Subscriber Identity (S-TMSI). In the case of a radio access network (RAN), the paging UE identity is an inactive RNTI (I-RNTI). For the paged UE, in addition to the UE identity, an accessType may also be included. The accessType indicates whether the paging message is initiated due to a protocol data unit (PDU) session from a non-3rd Generation Partnership Project (3GPP) access. For the paged UE, the paging message may also include a paging cause. For the paged UE, multiple paging causes may be included in the paging message. The paging cause indicates the reason for the paging. The paging cause can be critical services, voice, short message service (SMS), Internet Protocol Multimedia Subsystem (IMS) signaling, cyclic prefix (CP) signaling, and other data. For idle UEs, the access and mobility management function (AMF) will forward the paging cause in the paging message to the NG-RAN. The gNB in ​​the NR-RAN then includes it in the paging message transmitted on the PDSCH. For inactive UEs, the NG-RAN determines the paging cause based on the paging cause field contained in the CN tunnel header of the incoming DL PDU or based on the allocation and retention priority (ARP) of the QoS of the specific 5G quality of service (QoS) identifier (5QI) and the DL data, and the paging policy indicator (PPI) in the CN tunnel header.After receiving a paging message including a UE identity and a paging cause, the UE may respond to the paging in one of the following ways depending on the paging cause and the ongoing activity on the other SIM (for example, depending on whether the service indicated by the paging cause is important (has a higher priority) or compared to the ongoing activity on the other SIM): if the service indicated by the paging cause is more important than the ongoing activity on the other SIM or there is no ongoing activity on the other SIM, the UE in the RRC idle state may initiate a connection establishment procedure to enter a connected state, wherein the UE sends an RRCSetupRequest and the establishmentCause in the RRCSetupRequest is set to one of mps-PriorityAccess, mcs-PriorityAccess and mt-Access; or, if the service indicated by the paging cause is not important compared to the ongoing activity on the other SIM, the UE may initiate a procedure of sending an RRCSetupRequest, wherein the establishmentCause in the RRCSetupRequest is set to mt-busy, indicating that the UE is busy due to the ongoing activity on the other SIM. Upon receiving an RRCSetupRequest with establishmentCause set to mt-busy, the gNB may inform the AMF that the UE is busy due to ongoing activity on another SIM and send an RRCRelease message to the UE. The AMF may delay paging based on this indication from the gNB. In addition to mt-busy, the UE may also indicate how long it will be busy. Upon receiving an RRCSetupRequest with establishmentCause set to mps-PriorityAccess or mcs-PriorityAccess or mt-Access, the gNB sends an RRCSetup message to the UE to establish the connection. Note that if the UE decides to indicate mt-busy, it may first request gaps from the base station of the system of the other SIM and use these gaps to respond to the gNB with paging with an mt-busy indication. In an embodiment, instead of setting the establishmentCause to mt-busy, the UE may set the establishmentCause to mt-access and add an additional field in the message to indicate that the UE is busy.In an embodiment, after sending an establishmentCause set to mt-busy or an additional field in a message indicating that the UE is busy, when the UE becomes available, the UE may initiate a process of sending an RRCSetupRequest, wherein the establishmentCause in the RRCSetupRequest is set to mt-busy or mt-available or a new field indicating that the UE is available. The paging message may include multiple UE identities to page multiple UEs. The paging message is broadcast on a data channel (i.e., PDSCH) (i.e., PDCCH is masked with P-RNTI).

[0063] The UE monitors one PO per DRX cycle period. The UE determines its PO based on the UE_ID. The UE first determines the paging frame (PF), and then determines the PO for the determined PF. One PF is one radio frame (10ms). The PF of the UE is the radio frame with a SFN that satisfies the equation (SFN+PF_offset) mod T = (T div N) * (UE_ID mod N); where PF_offset, T and N are signaled by the gNB in ​​the SI. The UE monitors the (i_s+1)th PO, where i_s = floor(UE_ID / N) mod Ns; where N and Ns are signaled by the gNB in ​​the SI.

[0064] PO is a set of PDCCH monitoring opportunities that may consist of multiple time slots (e.g., subframes or orthogonal frequency division multiplexing (OFDM) symbols) in which paging DCI may be sent. If configured as specified in TS 38.331, the PDCCH monitoring opportunities for paging are determined according to the pagingSearchSpace and firstPDCCH-MonitoringOccasionOfPO specified in TS 38.213. When SearchSpaceId=0 is configured for pagingSearchSpace, the PDCCH monitoring opportunities for paging are the same as those for the remaining minimum system information (RMSI) defined in Section 13 of TS 38.213. The pagingSearchSpace is signaled by the gNB in ​​the SI and / or RRCReconfiguration message. The pagingSearchSpace is specific to the BWP and in idle / inactive cases, the UE uses this configuration in the connected active BWP and the initial DL BWP.

[0065] When SearchSpaceId=0 is configured for pagingSearchSpace, Ns is 1 or 2. When Ns=1, there is only one PO in the PF starting from the first PDCCH monitoring occasion for paging. For Ns=2, the PO is located in the first half frame (i_s=0) or the second half frame (i_s=1) of the PF.

[0066] When a SearchSpaceId other than 0 is configured for pagingSearchSpace, the UE monitors the (i_s+1)th PO. A PO is a set of "S*X" consecutive PDCCH monitoring opportunities, where "S" is the number of synchronization signal blocks (SSBs) actually transmitted as determined by ssb-PositionsInBurst in SIB1, and X is nrofPDCCH-MonitoringOccasionPerSSB-InPO if configured, otherwise X is 1. The [x*S+K]th PDCCH monitoring opportunity for paging in the PO corresponds to the Kth SSB transmitted, where x=0,1,…,X-1,K=1,2,…,S. PDCCH monitoring opportunities for paging that do not overlap with UL symbols (determined according to tdd-UL-DL-ConfigurationCommon) are numbered sequentially starting from 0, starting from the first PDCCH monitoring opportunity for paging in the PF. When firstPDCCH-MonitoringOccasionOfPO exists, the starting PDCCH monitoring opportunity number of the (i_s+1)th PO is the (i_s+1)th value of the firstPDCCH-MonitoringOccasionOfPO parameter; otherwise, the starting PDCCH monitoring opportunity number of the (i_s+1)th PO is equal to i_s*S*X. If X>1, when the UE detects a PDCCH transmission addressed to the P-RNTI within its PO, the UE does not need to monitor subsequent PDCCH monitoring opportunities for the PO.

[0067] Problem: In case of MUSIM UE, since RF is shared with another SIM B / Network B, the UE may miss monitoring paging from SIM A / Network A due to RF unavailability during its PO. Hence, the paging will be delayed since Network A can only resend the paging in the UE's PO in the next DRX cycle period. Figure 4 This further illustrates the problem. Figure 4 (a) illustrates time intervals in which the UE monitors the other SIM B (referred to as Network B). During these intervals, RF is not available for monitoring this SIM A (ie Network A). Figure 4(b) illustrates the paging DRX cycle period, PF, PO, PF and PO of the UE. It can be seen that the PO of the UE overlaps with the time when the UE is monitoring network B (the monitoring of network B can also be the paging monitoring in network B). As a result, the UE will miss the paging.

[0068] To solve the above problem, the following operations are performed in the embodiment of the present invention:

[0069] Step 1: The UE sends its unavailability information (e.g. gap pattern / unavailability pattern) to the AMF (of SIM A / network A). The unavailability information indicates the time when the UE cannot monitor the DL of (SIM A / network A), i.e. the time when the UE monitors another SIM B / network B. The AMF (of SIM A / network A) sends an acknowledgement.

[0070] - In an embodiment, the UE indicates unavailability information based on the SFN timing of its current cell. When the UE moves to a cell with different timing than the cell in which the UE last sent unavailability information, the UE may send an updated gap pattern / unavailability pattern to the AMF. The UE may also send an updated gap pattern / unavailability pattern to the AMF whenever the pattern / unavailability pattern changes. The UE may also inform the AMF when the UE is always available, i.e. it is no longer monitoring another SIM.

[0071] In an embodiment, the UE indicates the unavailable information based on a global time, such as Coordinated Universal Time (UTC). The unavailable information may be sent to the AMF using non-access stratum (NAS) signaling or an RRC signaling message. In the case of an RRC signaling message, the information is first sent to the gNB, and then the gNB forwards the information to the AMF.

[0072] In an embodiment, the unavailability information may consist of the following parameters: period (P), duration (D), and offset (O). In this case, the UE is periodically unavailable for a duration "D", where the duration starts from a SFN that satisfies SFN mod P = offset "O". The offset "O" may also be zero. In an embodiment, the UE may be partially unavailable during the duration "D". A bitmap may be additionally configured to indicate during which time slots in the duration "D" the UE is unavailable.

[0073] Step 2A: AMF (SIM A / Network A) initiates paging (e.g. when DL data for the UE arrives). The AMF (SIM A / Network A's) sends a paging message to one or more gNBs. In the paging message, the AMF (SIM A / Network A's) includes information about the unavailable information (i.e., gap pattern / unavailable pattern information) received from the UE.

[0074] Step 2A-1. As described above, the gNB determines the PF / PO of the paged UE based on the paging configuration and UE ID.

[0075] Step 2A-2. The gNB checks whether the determined PO overlaps with an unavailable period (a time period when the UE is unable to monitor the DL (of SIM A / Network A) (i.e., a time period when the UE is monitoring another SIM B / Network B).

[0076] If yes, the gNB pages the UE in the next PO that does not overlap with the UE's unavailability period.

[0077] In an embodiment, this is the first available PO that does not overlap with the UE's unavailability period. It may correspond to the same PF or a subsequent PF.

[0078] In an embodiment, this is the first available PO that does not overlap with the unavailability period of the UE in the next PF.

[0079] In an embodiment, this is the first available PO with the same PO index that does not overlap with the unavailability period of the UE in the subsequent PF.

[0080] In an embodiment, if there is an available PO corresponding to the UE's PF that does not overlap with the UE's unavailable period, the UE monitors it. This may appear before the UE's PO. If multiple such POs are available, the UE can select the one that appears first.

[0081] In an embodiment, from the start of the PF, this is the first available PO that does not overlap with the UE's unavailable period. It may correspond to the same PF or a subsequent PF. It may appear before or after the UE's PO.

[0082] If no, the gNB performs paging in the PO determined in step 2A-1.

[0083] Please note that step 2A-2 is performed in each DRX cycle period.

[0084] In step 2A-2, in an embodiment, the gNB determines the unavailable period based on its SFN timing and unavailable information received from the AMF. Alternatively, the gNB determines the unavailable period based on the UTC time and unavailable information received from the AMF.

[0085] Step 2B: The UE determines the PF / PO for paging reception based on the paging configuration and the UE ID.

[0086] Step 2B-1: The UE checks whether the determined PO overlaps with an unavailable period (a time period when the UE cannot monitor the DL (of SIM A / network A), ie, a time period when the UE is monitoring another SIM B / network B).

[0087] If yes, the UE monitors paging in the next PO which does not overlap with the UE's unavailability period.

[0088] In an embodiment, this is the first available PO that does not overlap with the unavailability period of the UE. It may correspond to the same PF or a subsequent PF.

[0089] In an embodiment, this is the first available PO that does not overlap with the unavailability period of the UE in the next PF.

[0090] In an embodiment, this is the first available PO with the same PO index that does not overlap with the unavailability period of the UE in subsequent PFs.

[0091] In an embodiment, if there is an available PO corresponding to the UE's PF that does not overlap with the UE's unavailable period, the UE monitors it. This may appear before the UE's PO. If multiple such POs are available, the UE can select the one that appears first.

[0092] In an embodiment, from the start of the PF, this is the first available PO that does not overlap with the UE's unavailable period. It may correspond to the same PF or a subsequent PF. It may appear before or after the UE's PO.

[0093] If no, the UE monitors the paging in the PO calculated in step 2B-1.

[0094] Please note that step 2B-1 is performed in each DRX cycle period.

[0095] In this design, the PF / PO monitored by the UE in each DRX cycle period may be different.

[0096] Figure 5 is an example illustration of such a method according to an embodiment based on the present disclosure. Figure 5 (a) shows time intervals in which the UE monitors the other SIM B (referred to as Network B). During these intervals, RF is not available for monitoring this SIM A (ie Network A). Figure 5 (b) shows the paging DRX cycle period, PF, PO, PF and PO of SIM A (i.e., network A). The PF and PO determined by the UE based on the PF / PO equation are PF 1 and PO a of SIM A (i.e., network A). In the DRX cycle period, the PO (i.e., PO a) calculated by the UE based on the PF / PO formula overlaps with the unavailable period (i.e., the time when the UE cannot monitor the DL (of SIM A / network A), i.e., the time when the UE is monitoring another SIM B / network B). Therefore, Figure 5As shown in (c), the UE monitors the next available PO (i.e., PO c of PF 1) that does not overlap with the unavailable period in the DRX cycle period. Note that even if Figure 5 It is shown that all POs of a PF are located within the PF, but it is possible that the POs of a PF may be located in a subsequent radio frame or may be located in multiple radio frames.

[0097] Figure 6 is an example illustration of such a method according to an embodiment based on the present disclosure. Figure 6 (a) shows the time intervals during which the UE monitors the other SIM B (referred to as Network B). During these intervals, RF is not available for monitoring this SIM A (ie Network A). Figure 6 (b) shows the paging DRX cycle period, PF, PO, PF and PO of SIM A (i.e., network A). The PF and PO determined by the UE based on the PF / PO equation are PF 1 and PO a of SIM A (i.e., network A). In the DRX cycle period, the PO (i.e., PO a) calculated by the UE based on the PF / PO equation overlaps with the unavailable period (i.e., the time when the UE cannot monitor the DL (of SIM A / network A), i.e., the time when the UE is monitoring another SIM B / network B). Therefore, Figure 6 As shown in (c), the UE monitors the next available PO (i.e., PO a of PF2), which does not overlap with the unavailable period in the DRX cycle. Figure 6 It is shown that all POs of a PF are located within the PF, but it is also possible that the POs of a PF may be located in a subsequent radio frame or may be located in multiple radio frames.

[0098] In the embodiment of the present disclosure, in the case of RAN paging, the AMF in the above description may be a RAN node (RAN anchor point).

[0099] Frequency Priority

[0100] The UE operates in F1 on network A (SIM A). The UE can be in RRC idle / RRC inactive state or in RRC connected state. The UE also resides in F2 on network B (SIM B). In network B, the UE is within the coverage of the cell in F2 and F3. Based on the priority information received in SI and / or dedicated signaling, the priority of F2>F3 is determined.

[0101] F1 and F2 share RF between SIM A and SIM B. F3 and F4 share RF between SIM A and SIM B. Therefore, when the UE operates on network A and network B through carriers F1 and F2 respectively, it needs to share RF in a time division multiplexing (TDM) manner. This is not efficient. If the RF is busy performing the required operation in network B, the UE cannot perform the required operation in network A.

[0102] In an embodiment of the present disclosure, if the MUSIM UE does not need to share its RF resources with another network / SIM by camping on the frequency, the MUSIM UE considers the priority of the frequency as the highest priority. This is independent of the absolute priority of the frequency indicated by the network (e.g., in the SI).

[0103] In other words, "if the RF is shared for the current camping / operating frequencies of network A and network B" and "if the RF is not shared for the camping / operating frequency of network B and another candidate frequency of network A": the MUSIM UE considers the candidate frequency of network A as the highest priority frequency for camping / operating in network A, regardless of the absolute priority of this candidate frequency indicated by the network (e.g., in SI).

[0104] Alternatively, among the candidate carrier frequencies of the network / SIM (i.e. frequencies available to one or more cells, or frequencies where one or more cells satisfy the S criteria specified in TS 38.304), the MUSIM UE considers the carrier frequency that does not share RF with the camped / operating carrier frequency of another network / SIM as the highest priority frequency. This is independent of the absolute priority of the frequencies indicated by the network (e.g. in SI).

[0105] In an embodiment, the MUSIM UE operates as follows:

[0106] 1. The MUSIM UE resides / operates on a cell on carrier frequency FA-1 of network A.

[0107] 2. The MUSIM UE resides / operates on a cell on carrier frequency FB-1 of network B.

[0108] 3. The MUSIM UE detects one or more cells on another carrier frequency FA-2 of network A (or the MUSIM UE detects one or more cells on another carrier frequency FA-2 that meets the S standard specified in TS 38.304). The priority of frequency FA-2 < the priority of frequency FA-1.

[0109] 4. For the current resident / operating frequencies of network A and network B (i.e., FA-1 and FB-1), RF is shared; and for the resident / operating frequency of network B and another candidate frequency of network A, RF is not shared:

[0110] A. The MUSIM UE considers the candidate frequency of network A (ie, FA-2) as the highest priority frequency to camp / operate in network A, even though the absolute priority of FA-2 is not the highest.

[0111] B. MUSIM UE reselects to carrier frequency FA-2.

[0112] In an embodiment, the MUSIM UE operates as follows:

[0113] 1. MUSIM UE camps / operates on a cell on carrier frequency FB-1 of network B / SIM B.

[0114] 2. One or more cells are available on carrier frequencies FA-1 and FA-2 of network A / SIM A. The priority of frequency FA-2 is less than the priority of frequency FA-1.

[0115] 3. Among the candidate carrier frequencies of network A (i.e., frequencies available to one or more cells, or frequencies of one or more cells that meet the S standard specified in TS 38.304), consider the carrier frequency that does not share RF with the resident / operating carrier frequency of network B as the highest priority frequency.

[0116] A. The MUSIM UE considers the candidate frequency of network A (ie, FA-2) as the highest priority frequency to camp / operate in network A, even though the absolute priority of FA-2 is not the highest.

[0117] B. MUSIM UE reselects to carrier frequency FA-2.

[0118] In an embodiment, an indicator may be broadcast in the cell that allows certain UE types (e.g., MUSIM UEs) to override the absolute frequency priority broadcast in the SI. If the override is allowed according to this indicator, then:

[0119] If the MUSIM UE does not need to share its RF resources with another network / SIM by camping on that frequency, the MUSIM UE considers the priority of that frequency as the highest priority. This is independent of the absolute priority of the frequency indicated by the network (e.g. in SI).

[0120] In other words, "if the RF is not shared for the current camping / operating frequencies of network A and network B" and "if the RF is not shared for the camping / operating frequency of network B and another candidate frequency of network A": the MUSIM UE considers the candidate frequency of network A as the highest priority frequency for camping / operating in network A, regardless of the absolute priority of this candidate frequency indicated by the network (e.g., in SI).

[0121] Alternatively, among the candidate carrier frequencies of a network / SIM (i.e., frequencies available to one or more cells), the MUSIM UE considers as the highest priority frequency a carrier frequency that does not share RF with a camped / operating carrier frequency of another network / SIM. This is independent of the absolute priority of the frequencies indicated by the network (e.g., in the SI).

[0122] In an embodiment, an indicator may be broadcast in the cell of each UE type (MUSIM UE, device-to-device (D2D) UE, vehicle-to-everything (V2X) UE, etc.) to override the absolute frequency priority broadcast in the SI. If the override is allowed according to this indicator of the MUSIM UE, then:

[0123] If the MUSIM UE does not need to share its RF resources with another network / SIM by camping on that frequency, the MUSIM UE considers the priority of that frequency as the highest priority. This is independent of the absolute priority of the frequency indicated by the network (e.g. in SI).

[0124] In other words, "if the RF is shared for the current camping / operating frequencies of network A and network B" and "if the RF is not shared for the camping / operating frequency of network B and another candidate frequency of network A": the MUSIM UE considers the candidate frequency of network A as the highest priority frequency for camping / operating in network A, regardless of the absolute priority of this candidate frequency indicated by the network (e.g., in SI).

[0125] Alternatively, among the candidate carrier frequencies of a network / SIM (i.e., frequencies available to one or more cells), the MUSIM UE considers a carrier frequency that does not share RF with a camped / operating carrier frequency of another network / SIM as the highest priority frequency. This is independent of the absolute priority of the frequencies indicated by the network (e.g., in the SI).

[0126] In another embodiment, in addition to the indicator (as explained above), the percentage of UEs that are allowed to be covered can also be indicated. For example, the network can broadcast a value "p" between 0 and 1. If coverage is allowed according to the indicator and the random number drawn by the UE between 0 and 1 is lower than "p", then:

[0127] If the MUSIM UE does not need to share its RF resources with another network / SIM by camping on that frequency, the MUSIM UE considers the priority of the frequency as the highest priority. This is independent of the absolute priority of the frequency indicated by the network (e.g. in SI).

[0128] In other words, "if the RF is shared for the current camping / operating frequencies of network A and network B" and "if the RF is not shared for the camping / operating frequency of network B and another candidate frequency of network A": the MUSIM UE considers the candidate frequency of network A as the highest priority frequency for camping / operating in network A, regardless of the absolute priority of this candidate frequency indicated by the network (e.g., in SI).

[0129] Alternatively, among the candidate carrier frequencies of a network / SIM (i.e., frequencies available to one or more cells), the MUSIM UE considers a carrier frequency that does not share RF with a camped / operating carrier frequency of another network / SIM as the highest priority frequency. This is independent of the absolute priority of the frequencies indicated by the network (e.g., in the SI).

[0130] In another embodiment, the network may broadcast a value 'p' between 0 and 1. If 'p' is not signaled, then no overlay is allowed. If 'p' is signaled and the random number drawn by the UE between 0 and 1 is lower than 'p', then:

[0131] If the MUSIM UE does not need to share its RF resources with another network / SIM by camping on that frequency, the MUSIM UE considers the priority of the frequency as the highest priority. This is independent of the absolute priority of the frequency indicated by the network (e.g. in SI).

[0132] In other words, "if the RF is shared for the current camping / operating frequencies of network A and network B" and "the RF is not shared for the camping / operating frequency of network B and another candidate frequency of network A": then the MUSIM UE considers the candidate frequency of network A as the highest priority frequency for camping / operating in network A, regardless of the absolute priority of the candidate frequencies indicated by the network (e.g., in the SI).

[0133] Alternatively, among the candidate carrier frequencies of a network / SIM (i.e., frequencies available to one or more cells), the MUSIM UE considers a carrier frequency that does not share RF with a camped / operating carrier frequency of another network / SIM as the highest priority frequency. This is independent of the absolute priority of the frequencies indicated by the network (e.g., in the SI).

[0134] In an embodiment, the UE may send assistance information to the network.

[0135] Regardless of whether the UE is DSDS or dual SIM dual reception (DSDR), the UE provides TDM assistance information and / or frequency division multiplexing (FDM) assistance information.

[0136] It is up to the network to dictate whether to provide a TDM or FDM solution.

[0137] The TDM scheme involves configuring gaps that allow the UE to monitor other SIMs (for example, if the UE is DSDS). The UE can inform the gNB of the gap period and gap length. The gNB can then confirm or provide the gap configuration in the RRCReconfiguration message for monitoring of other SIMs. In an embodiment, the gNB can configure multiple configurations. The UE can select a configuration based on its needs and notify the gNB of the selected configuration using a MAC CE or an RRC message. Alternatively, the gNB can activate a configuration using a MAC CE or DCI. The UE uses the activated configuration and can monitor other SIMs during the gap according to the activated configuration.

[0138] The FDM scheme in the form of dedicated priority or redirection information in the RRC Release message allows the UE to override the absolute priority for cell reselection or to use the redirection information to establish a new RRC connection on a cell of a different frequency.

[0139] In connected mode, the UE can notify network B to avoid configuring frequencies that the UE cannot monitor simultaneously based on the operating frequency of network A. UE assistance information can be used for this. For example, if the operating frequency of network A is F1 and RF is shared between F2 and F1, the MUSIM UE can notify network B not to configure F2. Network B can avoid switching to F2 or avoid configuring it as a secondary cell (SCell) in carrier aggregation (CA) mode.

[0140] Figure 7 is a block diagram of a terminal according to an embodiment of the present invention.

[0141] refer to Figure 7 The terminal includes a transceiver 710, a controller 720, and a memory 730. The controller 720 may refer to a circuit, an ASIC, an FPGA, or at least one processor. The transceiver 710, the controller 720, and the memory 730 are configured to perform, for example Figures 1 to 6 The operations of the UE shown in or other UEs described above. Although the transceiver 710, the controller 720, and the memory 730 are shown as separate entities, they may be integrated into a single chip. The transceiver 710, the controller 720, and the memory 730 may also be electrically connected or coupled to each other.

[0142] The transceiver 710 can send signals to other network entities (e.g., base stations) and receive signals from other network entities. The controller 720 can control the UE to perform the functions according to the above-mentioned embodiments. In an embodiment, a memory 730 storing corresponding program codes can be used to implement the operation of the terminal. Specifically, the terminal can be equipped with a memory 730 to store program codes for implementing desired operations. In order to perform the desired operation, the controller 720 can read and execute the program codes stored in the memory 730 by using a processor or a central processing unit (CPU).

[0143] Figure 8 is a block diagram of a base station according to an embodiment of the present disclosure.

[0144] refer to Figure 8 , the base station includes a transceiver 810, a controller 820, and a memory 830. The controller 820 may refer to a circuit, an ASIC, an FPGA, or at least one processor. The transceiver 810, the controller 820, and the memory 830 are configured to perform the operations of other gNBs (or networks) shown in the figure or described above. Although the transceiver 810, the controller 820, and the memory 830 are shown as separate entities, they may be integrated into a single chip. The transceiver 810, the controller 820, and the memory 830 may also be electrically connected or coupled to each other.

[0145] The transceiver 810 may send signals to and receive signals from other network entities (e.g., terminals). The controller 820 may control the gNB to perform functions according to an embodiment of the present disclosure. In an embodiment, a memory 830 storing corresponding program codes may be used to implement the operation of the base station. Specifically, the base station may be equipped with a memory 830 to store program codes for implementing desired operations. In order to perform the desired operation, the controller 820 may read and execute the program code stored in the memory 830 by using a processor or CPU.

[0146] While the present disclosure has been shown and described with reference to various embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made without departing from the spirit and scope of the present disclosure as defined by the appended claims and their equivalents.

[0147] Although the present disclosure has been described with various embodiments, various changes and modifications may occur to those skilled in the art. The present disclosure is intended to encompass such changes and modifications as fall within the scope of the appended claims.

Claims

1. A method performed by a terminal in a wireless communication system, the method comprising: Monitoring, by a terminal having at least two subscriber identity module (SIM) capabilities, a system information (SI) update indication in at least one first paging occasion of at least one modification period of a first network associated with a first SIM; identifying that the terminal fails to monitor the at least one first paging occasion due to monitoring the second SIM; Upon resuming monitoring of the first network associated with the first SIM, reading the master information block MIB and the system information block 1 SIB1 to determine whether any SI is updated; determining whether any SI is updated based on the MIB and the SIB1; and In case any SI is updated, the updated SI is acquired.

2. The method of claim 1, wherein: Monitoring the SI update indication comprises monitoring a physical downlink control channel, PDCCH, addressed by a paging radio network temporary identifier, P-RNTI, in any paging occasion in each modification period.

3. The method of claim 1, wherein: The at least one first paging occasion is selected based on an identifier ID of the terminal.

4. The method of claim 1, wherein: In a case where the terminal fails to monitor the at least one first paging occasion within a certain number of consecutive modification time periods, the terminal fails to monitor the at least one first paging occasion.

5. The method according to claim 4, in, The value of the number of consecutive modification periods is signaled from the base station in the SI.

6. The method of claim 1, wherein: The terminal is in a radio resource control RRC idle state or an RRC inactive state.

7. A terminal in a wireless communication system, the terminal comprising: transceiver (710); and At least one processor (720) operably coupled to the transceiver and configured to: monitoring, by the terminal having at least two subscriber identity module SIM capabilities, a system information SI update indication in at least one first paging occasion of at least one modification period of a first network associated with a first SIM, identifying that the at least one processor failed to monitor the at least one first paging occasion due to monitoring the second SIM, Once monitoring of the first network associated with the first SIM is resumed, the master information block MIB and the system information block 1 SIB1 are read to determine whether any SI has been updated, determining whether any SI is updated based on the MIB and the SIB1, and In case any SI is updated, the updated SI is acquired.

8. The terminal according to claim 7, wherein: The at least one processor (720) is further configured to monitor the SI update indication by monitoring a physical downlink control channel (PDCCH) addressed by a paging radio network temporary identifier (P-RNTI) in any paging occasion in each modification period.

9. The terminal according to claim 7, wherein: The at least one first paging occasion is selected based on an identifier ID of the terminal.

10. The terminal according to claim 7, wherein: In the event that the at least one processor (720) fails to monitor the at least one first paging occasion within a certain number of consecutive modification periods, the at least one processor fails to monitor the at least one first paging occasion.

11. The terminal according to claim 10, in, The value of the number of consecutive modification periods is signaled from the base station in the SI.

12. The terminal according to claim 7, wherein: The terminal is in a radio resource control RRC idle state or an RRC inactive state.

Images