Method and user equipment to improve emergency services during and after discontinuous coverage

Abstract

A method for improving emergency service during and after discontinuous coverage is applied to a user equipment (UE), comprising the following steps. A non-access stratum (NAS) signaling wait timer is run for a period of time. An emergency protocol data unit (PDU) session is established within the time period. Alternatively, an emergency service fallback procedure is executed within the time period. An NAS signaling is initiated.

Description

[0001] Cross-referencing

[0002] This application claims priority to Indian Patent Application No. 202321046285, filed on July 10, 2023, and Indian Patent Application No. 202321057690, filed on August 28, 2023, the entire contents of which are incorporated herein by reference. [Technical Field]

[0003] This invention relates to a method for performing 5G NR operations in intermittent coverage, and more particularly to a method and user equipment (UE) for improving high-priority and emergency services during and after intermittent coverage. [Background Technology]

[0004] Current technology provides a deployment option for satellite E-UTRAN or NG-RAN access, where a shorter satellite E-UTRAN or NG-RAN access radio coverage period is followed by a longer satellite E-UTRAN or NG-RAN access coverage gap. During the coverage gap, the access layer may be deactivated. These coverage gaps are referred to as intermittent coverage.

[0005] When the Intermittent Coverage Non-Access Stratum (NAS) signaling wait timer is running, the UE is not allowed to execute the registration procedure. When the UE is configured for high-priority access in a selected Public Land Mobile Network (PLMN), the high-priority access service procedure will be triggered when the random timer expires, which will delay the processing of high-priority access. In emergency situations, this delay will impact the user experience.

[0006] When the intermittent coverage NAS signaling wait timer is running, the UE is not allowed to execute the registration procedure, and the emergency service fallback procedure is not allowed to be triggered. This will delay the establishment of emergency calls. [Summary of the Invention]

[0007] One embodiment of the present invention provides a method for improving emergency services during and after intermittent coverage. The method is applied to a user equipment (UE). The method includes the following steps: running a non-access stratum (NAS) signaling wait timer for a period of time; establishing an emergency protocol data unit (PDU) session during the period of time; performing an emergency service rollback procedure during the period of time; and initiating NAS signaling.

[0008] According to the above method, NAS signaling is a mobility registration updater or a tracking area updater.

[0009] The method further includes the following steps: receiving a request from an upper layer to perform an emergency service rollback procedure; selecting Evolved Universal Terrestrial Radio Access Network (E-UTRAN), GSM EDGE Radio Access Network (GERAN), or UMTS Terrestrial Radio Access Network (UTRAN) for the emergency service; or performing initial registration of the emergency service; or notifying the upper layer of the failure of the emergency service rollback procedure.

[0010] The method further includes the following steps: the user equipment (UE) has a pending emergency service rollback procedure; selects Evolved Universal Terrestrial Radio Access Network (E-UTRAN), GSM EDGE Radio Access Network (GERAN), or UMTS Terrestrial Radio Access Network (UTRAN) for the emergency service; or performs initial registration for the emergency service; or notifies the upper layer of the failure of the pending emergency service rollback procedure.

[0011] The method further includes the following steps: the user equipment (UE) has an established emergency protocol data unit (PDU) session; selects an evolved universal terrestrial radio access network (E-UTRAN), a GSM EDGE radio access network (GERAN), or a UMTS terrestrial radio access network (UTRAN) for emergency services; or performs initial registration for emergency services; or notifies the upper layer of the failure of the established emergency PDU session.

[0012] According to the above method, the NAS signaling wait timer runs for a period of time starting from a random value and ending at a maximum storage time offset value, which is generated when the currently registered tracking area (TA) returns to coverage after being outside the coverage area due to intermittent coverage.

[0013] The method further includes the following steps: the user equipment (UE) is configured for high-priority access in a selected public land mobile network (PLMN); receives and stores a maximum NAS signaling wait time; does not use the maximum NAS signaling wait time; or, does not use the maximum NAS signaling wait time to start a NAS signaling wait timer.

[0014] One embodiment of the present invention also provides a user equipment (UE) for improving emergency services during and after intermittent coverage. The UE includes a processor. The processor is configured to run a non-access stratum (NAS) signaling wait timer for a period of time; establish an emergency protocol data unit (PDU) session during the period of time; or, execute an emergency service rollback procedure and initiate NAS signaling during the period of time.

[0015] According to the aforementioned user equipment, after the NAS signaling wait timer starts running, the processor is configured to receive a request from an upper layer to execute an emergency service rollback procedure; select Evolved Universal Terrestrial Radio Access Network (E-UTRAN), GSM EDGE Radio Access Network (GERAN), or UMTS Terrestrial Radio Access Network (UTRAN) for the emergency service; or perform initial registration for the emergency service; or notify the upper layer of the failure of the emergency service rollback procedure.

[0016] According to the aforementioned user equipment, after the NAS signaling wait timer starts running, the processor is configured to have a pending emergency service rollback procedure; select Evolved Universal Terrestrial Radio Access Network (E-UTRAN), GSM EDGE Radio Access Network (GERAN), or UMTS Terrestrial Radio Access Network (UTRAN) for the emergency service; or perform initial registration of the emergency service; or notify the upper layer of the failure of the pending emergency service rollback procedure.

[0017] According to the aforementioned user equipment, after the intermittent coverage NAS signaling wait timer starts running, the processor is configured to have an established emergency protocol data unit (PDU) session; select Evolved Universal Terrestrial Radio Access Network (E-UTRAN), GSM EDGE Radio Access Network (GERAN), or UMTS Terrestrial Radio Access Network (UTRAN) for the emergency service; or perform initial registration for the emergency service; or notify the upper layer of the failure of the established emergency PDU session.

[0018] Based on the aforementioned user equipment, NAS signaling is either a mobility registration updater or a tracking area updater.

[0019] According to the aforementioned user equipment, the NAS signaling wait timer runs for a period of time starting from a random value and ending at a maximum storage time offset value, which is generated when the currently registered tracking area (TA) returns to coverage after being out of coverage due to intermittent coverage.

[0020] According to the aforementioned user equipment, the processor is configured to perform a high-priority access in a selected Public Land Mobile Network (PLMN); receive and store a maximum NAS signaling wait time; not use the maximum NAS signaling wait time; or, not use the maximum NAS signaling wait time to start a NAS signaling wait timer. [Attached Image Description]

[0021] A more complete understanding of the invention can be obtained by reading the following detailed description and referring to the accompanying drawings, wherein:

[0022] Figure 1A flowchart showing a method for improving emergency services during and after intermittent coverage, according to some embodiments of the present invention;

[0023] Figure 2 Showing some embodiments according to the present invention Figure 1 A flowchart illustrating methods for improving emergency services during and after intermittent coverage.

[0024] Figure 3 Showing some embodiments according to the present invention Figure 1 A flowchart illustrating methods for improving emergency services during and after intermittent coverage.

[0025] Figure 4 Showing some embodiments according to the present invention Figure 1 A flowchart illustrating methods for improving emergency services during and after intermittent coverage.

[0026] Figure 5 Showing some embodiments according to the present invention Figure 1 A flowchart illustrating methods for improving emergency services during and after intermittent coverage.

[0027] Figure 6 The diagram illustrates a method for improving high-priority service during and after intermittent coverage, according to some embodiments of the present invention; and

[0028] Figure 7 A schematic diagram of a communication system 700 according to some embodiments of the present invention is shown.

Detailed Implementation Methods

[0029] To make the above-described objects, features and advantages of certain embodiments of the present invention more readily understood, a detailed description is provided below in conjunction with the accompanying drawings.

[0030] Throughout this specification and the following claims, certain terms are used to refer to specific components. As will be understood by those skilled in the art, electronic device manufacturers may use different names to refer to a component. This document is not intended to distinguish between components with different names but the same function. It should be understood that the words “comprising,” “having,” and “including” are used in an open-ended manner and should therefore be interpreted as “including but not limited to…”. Therefore, when the terms “comprising,” “having,” or “including” are used in this invention to indicate the presence of a specific technical feature, value, method step, operation, unit, or component, it does not preclude the possibility of adding more technical features, values, method steps, operating processes, units, components, or any combination thereof.

[0031] Directional terms used throughout the specification and the following claims, such as “upper,” “above,” “lower,” “below,” “front,” “rear,” “back,” “left,” “right,” etc., refer only to the orientation of the drawings. Therefore, directional terms are used to interpret, and not to limit, the invention. Regarding the drawings, they illustrate general features of methods, structures, or materials used in specific embodiments. However, the drawings should not be construed as defining or limiting the scope or characteristics covered by these embodiments. For example, for clarity, the relative size, thickness, and position of each layer, region, or structure may be reduced or enlarged.

[0032] When a component, such as a layer or area, is referred to as "on another component," it can be directly on that other component, or there may be other components between them. On the other hand, when a component is referred to as "directly on another component (or a variation thereof)," there are no components between them. Furthermore, when a component is referred to as "on another component," the component and the other component have an arrangement relationship in the top view / vertical direction; the component can be below or above the other component, and the arrangement relationship in the top view / vertical direction is determined by the orientation of the device.

[0033] It should be understood that when a component or layer is said to be "connected to" another component or layer, it can be directly connected to that other component or layer, or there may be intermediate components or layers. Conversely, when a component is said to be "directly connected to" another component or layer, there are no intermediate components or layers.

[0034] The electrical connections or couplings described in this disclosure may refer to direct or indirect connections. In the case of a direct connection, the endpoints of components on two circuits are directly connected or connected by a segment of wire, while in the case of an indirect connection, there is a switch, diode, capacitor, inductor, resistor, other suitable component, or combination of the above components between the endpoints of components on two circuits, but the intermediate component is not limited to this.

[0035] The terms “first,” “second,” “third,” “fourth,” “fifth,” and “sixth” are used to describe components. They are not used to indicate priority or sequence, but only to distinguish components with the same name.

[0036] It should be noted that the technical features in the different embodiments described below can be substituted for, recombine or mixed with each other to form another embodiment without departing from the spirit of the invention.

[0037] Figure 1This diagram shows a flowchart of a method for improving emergency services during and after intermittent coverage according to some embodiments of the present invention. The method is applied to a user equipment (UE). In some embodiments, the UE may be, for example, a laptop computer, tablet computer, smartphone, smartwatch, etc., but the invention is not limited thereto. Figure 1 As shown, the method includes the following steps: Running a Non-Access Stratum (NAS) signaling wait timer for a period of time (step S100). Establishing an Emergency Protocol Data Unit (PDU) session within the time period (step S102) or performing an emergency service rollback procedure within the time period (step S106). Initiating a NAS signaling (step S104).

[0038] In some embodiments of step S100, if the UE has stored a maximum NAS signaling wait time for intermittent coverage, upon returning to coverage after being outside coverage due to intermittent coverage, the UE sets the maximum NAS signaling wait time value to a random value until the maximum intermittent coverage NAS signaling wait time stored for the selected Public Land Mobile Network (PLMN) and Satellite Next Generation Radio Access Network (NG-RAN) Radio Access Technology (RAT) type, and starts a NAS signaling wait timer. In step S102, the UE establishes an emergency PDU session within the time period. In step S106, the UE performs an emergency service fallback procedure within the time period. In some embodiments, the UE may perform steps S102 or S106 after performing step S100. Next, in step S104, the UE initiates a NAS signaling. In some embodiments, the NAS signaling is a mobility registration procedure or a tracking area (TA) update procedure. In some embodiments, the NAS signaling wait timer runs for a period starting at a random value and continuing until a stored maximum time offset value is reached. The maximum storage time offset value is generated when the currently registered TA returns to coverage after being out of coverage due to intermittent coverage.

[0039] Figure 2 Showing some embodiments of the present invention in Figure 1 A flowchart illustrating methods for improving emergency services during and after coverage disruptions. Figure 2 As shown, the method for improving emergency services during and after intermittent coverage includes the following steps: Receiving a request from the upper layer to perform an emergency service rollback procedure (step S200). Alternatively, selecting Evolved Universal Terrestrial Radio Access Network (E-UTRAN), GSM EDGE Radio Access Network (GERAN), or UMTS Terrestrial Radio Access Network (UTRAN) for emergency services (step S204). Alternatively, performing initial registration for emergency services (step S208). Alternatively, notifying the upper layer of the failure of the emergency service rollback procedure (step S206).

[0040] In step S200, the user equipment (UE) receives a request from the upper layer to perform an emergency service rollback procedure. In some embodiments, after performing step S200, the UE may perform at least one of steps S204, S206, and S208. For example, in step S204, the UE attempts to select E-UTRAN, GERAN, or UTRAN for emergency services. In step S208, the UE performs initial registration for emergency services. In step S206, the UE notifies the upper layer of the failure of the emergency service rollback procedure, signaling procedure, or registration procedure.

[0041] In some embodiments, when the intermittent coverage NAS signaling wait timer is running, the UE will not initiate any NAS signaling on NG-RAN Radio Access Technology (RAT) types and selected Public Land Mobile Networks (PLMNs). If the UE receives a paging message or is performing an emergency service rollback procedure, the UE will stop the NAS signaling wait timer and initiate NAS signaling.

[0042] Figure 3 Showing some embodiments of the present invention in Figure 1 A flowchart illustrating methods for improving emergency services during and after coverage disruptions. Figure 3 As shown, the method for improving emergency services during and after intermittent coverage includes the following steps: The UE has a pending emergency service fallback procedure (step S300). E-UTRAN, GERAN, or UTRAN is selected for the emergency service (step S304). Alternatively, initial registration for the emergency service is performed (step S308). Alternatively, the failure of the pending emergency service fallback procedure is notified to the upper layer (step S306).

[0043] In step S300, the UE has an emergency service rollback procedure to be processed. In some embodiments, after executing step S300, the UE may execute at least one of steps S304, S306, and S308. For example, in step S304, the UE attempts to select E-UTRAN, GERAN, or UTRAN for emergency services. In step S308, the UE performs initial registration for emergency services. In step S306, the UE notifies the upper layer of the failure of the pending emergency service rollback procedure, signaling procedure, or registration procedure.

[0044] In some embodiments, when the NAS signaling wait timer is running, the UE will not initiate any NAS signaling on the NG-RAN Radio Access Technology (RAT) type and the selected PLMN. If the UE has pending emergency services, the UE will stop the NAS signaling wait timer and initiate NAS signaling.

[0045] Figure 4 Showing some embodiments of the present invention in Figure 1 A flowchart illustrating methods for improving emergency services during and after coverage disruptions. Figure 4 As shown, the method for improving emergency services during and after intermittent coverage includes the following steps: The UE has an established Emergency Protocol Data Unit (PDU) session (step S400). Alternatively, E-UTRAN, GERAN, or UTRAN is selected for emergency services (step S404). Alternatively, initial registration for emergency services is performed (step S408). Alternatively, the failure of the established emergency PDU session with the upper layer is notified (step S406).

[0046] In step S400, the UE has an established emergency PDU session. In some embodiments, after performing step S400, the UE may perform at least one of steps S404, S406, and S408. For example, in step S404, the UE attempts to select E-UTRAN, GERAN, or UTRAN for emergency services. In step S408, the UE performs initial registration for emergency services. In step S406, the UE notifies the upper layer of the failure of the established emergency PDU session, signaling procedure, or registration procedure.

[0047] In some embodiments, when the NAS signaling wait timer is running, the UE will not initiate any NAS signaling on the NG-RAN Radio Access Technology (RAT) type and the selected PLMN. If the UE enters a Tracking Area Identifier (TAI) outside the registered area, the UE will stop the NAS signaling wait timer and initiate NAS signaling.

[0048] Figure 5 Showing some embodiments of the present invention in Figure 1 A flowchart illustrating methods for improving emergency services during and after coverage disruptions. Figure 5 As shown, the method for improving emergency services during and after intermittent coverage includes the following steps: Establishing an emergency PDU session (step S500). Alternatively, selecting an evolved universal terrestrial radio access network (E-UTRAN), a GSM EDGE radio access network (GERAN), or a UMTS terrestrial radio access network (UTRAN) for emergency services (step S504). Alternatively, performing initial registration for emergency services (step S508). Alternatively, notifying the upper-layer emergency PDU session of failure (step S506).

[0049] In step S500, the UE establishes an emergency PDU session. In some embodiments, after performing step S500, the UE may perform at least one of steps S504, S506, and S508. For example, in step S504, the UE attempts to select E-UTRAN, GERAN, or UTRAN for emergency services. In step S508, the UE performs initial registration for emergency services. In step S506, the UE notifies the upper-layer emergency PDU session, signaling procedure, or registration procedure of the failure.

[0050] In some embodiments, when the Non-Access Stratum (NAS) signaling wait timer is running, the User Equipment (UE) will not initiate any NAS signaling on the NG-RAN radio access technology type and the selected Public Land Mobile Network (PLMN). If the UE is establishing an Emergency Protocol Data Unit (PDU) session, the UE stops the NAS signaling wait timer and initiates NAS signaling.

[0051] Figure 6 This diagram illustrates a method for improving high-priority service during and after intermittent coverage according to some embodiments of the present invention. The method is applied to a user equipment (UE). In some embodiments, the UE may be, for example, a laptop computer, tablet computer, smartphone, smartwatch, etc., but the invention is not limited thereto. Figure 6 As shown, the method for improving high-priority service during and after intermittent coverage includes the following steps: The UE is configured for high-priority access in the selected PLMN (step S600). The UE receives and stores the maximum Non-Access Stratum (NAS) signaling wait time (step S602). The UE does not use the maximum NAS signaling wait time (step S604). Alternatively, the UE does not use the maximum NAS signaling wait time to start a NAS signaling wait timer (step S606). Figure 6 and Figure 1 The main difference between the methods in [the text] is that, in Figure 6 In the NAS, the signaling wait timer is never started.

[0052] Figure 7 A schematic diagram of a communication system 700 according to some embodiments of the present invention is shown. For example... Figure 7 As shown, the communication system 700 includes a UE 702, a network 704, and a base station 706. In some embodiments, the UE 702 may be a laptop computer, tablet computer, smartphone, or smartwatch, but the invention is not limited thereto. In some embodiments, the UE 702 can access the network 704 through the base station 706. The UE 702 connects to the base station 706 via Radio Resource Control (RRC) signaling, but the invention is not limited thereto. In some embodiments, the base station 706 may be a gNB, but the invention is not limited thereto.

[0053] In some embodiments, UE 702 includes an antenna 712, a transceiver 708, and a processor 710. The transceiver 708 is electrically connected between the antenna 712 and the processor 710. The processor 710 may be a modem, but the invention is not limited thereto. In some embodiments, UE 702 also includes a memory (not shown) storing a plurality of codes. The processor 710 reads the codes stored in the memory to perform the following steps. In some embodiments, the processor 710 runs a NAS signaling wait timer for a period of time. The processor 710 establishes an Emergency Protocol Data Unit (PDU) session or performs an Emergency Service Rollback procedure during the period of time. The NAS signaling wait timer runs for a period of time starting from a random value and continuing until a stored maximum time offset value is reached. The stored maximum time offset value is generated when a currently registered TA returns to coverage after being out of coverage due to intermittent coverage. The processor 710 initiates NAS signaling. In some embodiments, the NAS signaling is a mobility registration update procedure or a tracking area update procedure, but the invention is not limited thereto.

[0054] In some embodiments, after the intermittent coverage NAS signaling wait timer runs, the processor 710 receives a request from the upper layer to execute an emergency service rollback procedure. The processor 710 then selects E-UTRAN, GERAN, or UTRAN for the emergency service, or performs initial registration of the emergency service, or notifies the upper layer of the failure of the emergency service rollback procedure.

[0055] In some embodiments, after the intermittent coverage NAS signaling wait timer runs, the processor 710 has a pending emergency service rollback procedure. The processor 710 then selects E-UTRAN, GERAN, or UTRAN for the emergency service, or performs initial registration of the emergency service, or notifies the upper-layer pending emergency service rollback procedure, signaling procedure, or registration procedure of failure.

[0056] In some embodiments, after the intermittent coverage NAS signaling wait timer runs, the processor 710 has an established PDU session. Then, the processor 710 selects E-UTRAN, GERAN, or UTRAN for the emergency service, or performs initial registration for the emergency service, or notifies the upper-layer layer of the failure of the established emergency PDU session, signaling procedure, or registration procedure.

[0057] In some embodiments, processor 710 is configured to perform high-priority access in a selected PLMN. Processor 710 receives and stores the maximum NAS signaling wait time. Subsequently, processor 710 does not use the maximum NAS signaling wait time. Processor 710 does not use the maximum NAS signaling wait time to start a NAS signaling wait timer.

[0058] While the invention has been described by way of examples and preferred embodiments, it should be understood that the invention is not limited to the disclosed embodiments. Rather, it is intended to cover various modifications and similar arrangements (as would be understood by those skilled in the art). Therefore, the scope of the appended claims should be given the broadest interpretation to cover all such modifications and similar arrangements.

Claims

1. A method for improving emergency services during and after intermittent coverage, applied to a user equipment (UE), characterized in that, include: Run a Non-Access Stratum (NAS) signaling wait timer for a period of time; as well as Establish an Emergency Protocol Data Unit (PDU) session during this time period; or During this period, an emergency service rollback procedure is executed, and a NAS signaling is initiated.

2. The method as described in claim 1, characterized in that, The NAS signaling is either a mobility registration updater or a tracking area updater.

3. The method as described in claim 1, characterized in that, Further includes: Receive a request from an upper layer to execute the emergency service rollback procedure; as well as For this emergency service, select an Evolved Universal Terrestrial Radio Access Network (E-UTRAN), a GSM EDGE Radio Access Network (GERAN), or a UMTS Terrestrial Radio Access Network (UTRAN); or An initial registration to perform this emergency service; or The notification indicates the failure of the emergency service rollback procedure at the higher level.

4. The method as described in claim 1, characterized in that, Further includes: It has a pending emergency service rollback procedure; as well as For this emergency service, select an Evolved Universal Terrestrial Radio Access Network (E-UTRAN), a GSM EDGE Radio Access Network (GERAN), or a UMTS Terrestrial Radio Access Network (UTRAN); or An initial registration to perform this emergency service; or Notify the upper level of the failure of the pending emergency service rollback procedure.

5. The method as described in claim 1, characterized in that, Further includes: It has an established Emergency Protocol Data Unit (PDU) session; as well as For this emergency service, select an Evolved Universal Terrestrial Radio Access Network (E-UTRAN), a GSM EDGE Radio Access Network (GERAN), or a UMTS Terrestrial Radio Access Network (UTRAN); or An initial registration to perform this emergency service; or Notify the upper layer of the failure of the established emergency PDU session.

6. The method as described in claim 1, characterized in that, The NAS signaling wait timer runs for a period of time that begins at a random value and continues until a maximum storage time offset value is reached, which is generated when the currently registered tracking area (TA) returns to coverage after being out of coverage due to intermittent coverage.

7. The method as described in claim 1, characterized in that, Further includes: Configured as a high-priority access in a selected Public Land Mobile Network (PLMN); as well as Receive and store a maximum NAS signaling wait time; as well as Do not use the maximum NAS signaling wait time; or Do not use the maximum NAS signaling wait time to start this NAS signaling wait timer.

8. A user equipment (UE) for improving emergency services during and after intermittent coverage, characterized in that, include: One processor, configured as follows: Run a Non-Access Stratum (NAS) signaling wait timer for a period of time; as well as Establish an Emergency Protocol Data Unit (PDU) session within this time period; or During this period, an emergency service rollback procedure is executed, and a NAS signaling is initiated.

9. The UE as described in claim 8, characterized in that, After the NAS signaling wait timer starts running, the processor is configured as follows: Receive a request from an upper layer to execute the emergency service rollback procedure, and For this emergency service, select an Evolved Universal Terrestrial Radio Access Network (E-UTRAN), a GSM EDGE Radio Access Network (GERAN), or a UMTS Terrestrial Radio Access Network (UTRAN); or An initial registration to perform this emergency service; or The notification indicates the failure of the emergency service rollback procedure at the higher level.

10. The UE as described in claim 8, characterized in that, After the NAS signaling wait timer starts running, the processor is configured as follows: It has a pending emergency service rollback procedure; and For this emergency service, select an Evolved Universal Terrestrial Radio Access Network (E-UTRAN), a GSM EDGE Radio Access Network (GERAN), or a UMTS Terrestrial Radio Access Network (UTRAN); or An initial registration to perform this emergency service; or Notify the upper level of the failure of the pending emergency service rollback procedure.

11. The UE as described in claim 8, characterized in that, After the NAS signaling wait timer starts running, the processor is configured as follows: It has an established Emergency Protocol Data Unit (PDU) session; and For this emergency service, select an Evolved Universal Terrestrial Radio Access Network (E-UTRAN), a GSM EDGE Radio Access Network (GERAN), or a UMTS Terrestrial Radio Access Network (UTRAN); or An initial registration to perform this emergency service; or Notify the upper layer of the failure of the established emergency PDU session.

12. The UE as described in claim 8, characterized in that, The NAS signaling is either a mobility registration updater or a tracking area updater.

13. The UE as described in claim 8, characterized in that, The NAS signaling wait timer runs for a period of time that begins at a random value and ends at a maximum storage time offset value, which is generated when the currently registered tracking area (TA) returns to coverage after being out of coverage due to intermittent coverage.

14. The UE as claimed in claim 8, characterized in that, The processor is configured as follows: Configured as a high-priority access in a selected Public Land Mobile Network (PLMN), and Receive and store a maximum NAS signaling wait time, and Do not use the maximum NAS signaling wait time; or Do not use the maximum NAS signaling wait time to start this NAS signaling wait timer.

Images