WO2025237261A1

WO2025237261A1 - Methods and apparatus for attempting to establish radio resource control connection in mobile communications

Info

Publication number: WO2025237261A1
Application number: PCT/CN2025/094455
Authority: WO
Inventors: Ren-Huang Liu; Marko NIEMI
Original assignee: MediaTek Inc
Current assignee: MediaTek Inc
Priority date: 2024-05-17
Filing date: 2025-05-13
Publication date: 2025-11-20
Anticipated expiration: 2026-11-17

Abstract

Various solutions for attempting to establish Radio Resource Control (RRC) connection with respect to an apparatus in mobile communications are described. The apparatus may increment an attempt counter in an event that a lower layer failure occurs. The lower layer failure may be associated with establishing an RRC connection. The apparatus may determine whether the attempt counter is less than a threshold. The apparatus may start a first timer in an event that the attempt counter is less than the threshold or a second timer in an event that the attempt counter is not less than the threshold. The apparatus may attempt to establish the RRC connection in an event that the first timer expires or the second timer expires.

Description

METHODS AND APPARATUS FOR ATTEMPTING TO ESTABLISH RADIO RESOURCE CONTROL CONNECTION IN MOBILE COMMUNICATIONS

CROSS REFERENCE TO RELATED PATENT APPLICATION (S)

The present disclosure is part of a non-provisional application claiming the priority benefit of U.S. Patent Application No. 63/648,746, filed 17 May 2024, the contents of which herein being incorporated by reference in their entirety.

TECHNICAL FIELD

The present disclosure is generally related to mobile communications and, more particularly, to attempting to establish radio resource control connection with respect to apparatus in mobile communications.

BACKGROUND

Unless otherwise indicated herein, approaches described in this section are not prior art to the claims listed below and are not admitted as prior art by inclusion in this section.

In fourth generation (4G) network and fifth generation (5G) network, when a User Equipment (UE) attempts to register with a network to obtain services, the UE may perform: (1) an attach or Tracking Area Update (TAU) procedure in a 4G network, or (2) a registration procedure in a 5G network. During these procedures, the UE may establish a Radio Resource Control (RRC) connection and transmit Non-Access Stratum (NAS) messages related to the attach, TAU or registration procedure.

In some scenarios, if the signal quality between the UE and the network is poor, the RRC connection may fail to establish, resulting in a lower-layer failure reported to a NAS layer. When a fixed number of lower-layer failures occurs, the UE may initiate a single timer, thereby preventing further attach, TAU, or registration attempts until expiration of the timer, which may result in a significant delay and inflexibility in network access.

Furthermore, some mechanisms may enable additional attach or TAU attempts in highly limited network scenarios. However, such mechanisms may not be applicable to other network scenarios (e.g., a Visiting Public Land Mobile Network (VPLMN) , a 5G network, or a sixth-generation (6G) network) . Accordingly, when lower layer failures reach a predefined threshold in such network scenarios (e.g., VPLMN, 5G network, 6G network, etc. ) , the UE may yet initiate the single timer, thereby preventing further attach, TAU, or registration attempts until expiration of the timer, which may still result in a significant delay and inflexibility in network access.

Accordingly, improving the delay and flexibility of establishing an RRC connection is an important consideration in newly developed wireless communication networks. Therefore, there is a need for schemes that enhance the delay performance and flexibility of RRC connection establishment.

SUMMARY

The following summary is illustrative only and is not intended to be limiting in any way. That is, the following summary is provided to introduce concepts, highlights, benefits and advantages of the novel and non-obvious techniques described herein. Select implementations are further described below in the detailed description. Thus, the following summary is not intended to identify essential features of the claimed subject matter, nor is it intended for use in determining the scope of the claimed subject matter.

An objective of the present disclosure is to propose solutions or schemes that address the aforementioned issues pertaining to attempting to establish radio resource control (RRC) connection with respect to apparatus in mobile communications.

In one aspect, a method may involve an apparatus incrementing an attempt counter in an event that a lower layer failure occurs. The lower layer failure may be associated with establishing an RRC connection. The method may further involve the apparatus determining whether the attempt counter is less than a threshold. The method may further involve the apparatus starting a first time in an event that the attempt counter is less than the threshold or a second timer in an event that the attempt counter is not less than the threshold. The method may further involve the apparatus attempting to establish the RRC connection in an event that the first timer expires or the second timer expires.

In one aspect, an apparatus may comprise a transceiver which, during operation, wirelessly communicates with a wireless network. The apparatus may also comprise a processor communicatively coupled to the transceiver. The processor, during operation, may perform operations comprising incrementing an attempt counter in an event that a lower layer failure occurs. The lower layer failure may be associated with establishing an RRC connection. The processor may further perform operations comprising determining whether the attempt counter is less than a threshold. The processor may further perform operations comprising starting a first timer in an event that the attempt counter is less than the threshold or a second timer in an event that the attempt counter is not less than the threshold. The processor may further perform operations comprising attempting to establish the RRC connection in an event that the first timer expires or the second timer expires.

In one aspect, a method may involve an apparatus starting a timer in an event that a number of lower layer failures reaches a threshold. The number of lower layer failures may be associated with establishing a Radio Resource Control (RRC) connection with a first satellite network node. The method may further involve the apparatus stopping the timer in an event that the apparatus loses the first satellite network node or in an event that the apparatus selects a second satellite network node.

It is noteworthy that, although description provided herein may be in the context of certain radio access technologies, networks and network topologies such as Long-Term Evolution (LTE) , LTE-Advanced, LTE-Advanced Pro, 5th Generation (5G) , New Radio (NR) , Internet-of-Things (IoT) and Narrow Band Internet of Things (NB-IoT) , Industrial Internet of Things (IIoT) , and 6th Generation (6G) , the proposed concepts, schemes and any variation (s) /derivative (s) thereof may be implemented in, for and by other types of radio access technologies, networks and network topologies. Thus, the scope of the present disclosure is not limited to the examples described herein.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are included to provide a further understanding of the disclosure and are incorporated in and constitute a part of the present disclosure. The drawings illustrate implementations of the disclosure and, together with the description, serve to explain the principles of the disclosure. It is appreciable that the drawings are not necessarily in scale as some components may be shown to be out of proportion than the size in actual implementation in order to clearly illustrate the concept of the present disclosure.

FIG. 1 is a diagram depicting an example scenario under schemes in accordance with implementations of the present disclosure.

FIGs. 2A and 2B are diagrams depicting an example scenario under schemes in accordance with implementations of the present disclosure.

FIG. 3 is a diagram depicting an example scenario under schemes in accordance with implementations of the present disclosure.

FIG. 4 is a block diagram of an example communication system in accordance with an implementation of the present disclosure.

FIG. 5 is a flowchart of an example process in accordance with an implementation of the present disclosure.

FIG. 6 is a flowchart of an example process in accordance with an implementation of the present disclosure.
DETAILED DESCRIPTION OF PREFERRED IMPLEMENTATIONS

Detailed embodiments and implementations of the claimed subject matters are disclosed herein. However, it shall be understood that the disclosed embodiments and implementations are merely illustrative of the claimed subject matters which may be embodied in various forms. The present disclosure may, however, be embodied in many different forms and should not be construed as limited to the exemplary embodiments and implementations set forth herein. Rather, these exemplary embodiments and implementations are provided so that description of the present disclosure is thorough and complete and will fully convey the scope of the present disclosure to those skilled in the art. In the description below, details of well-known features and techniques may be omitted to avoid unnecessarily obscuring the presented embodiments and implementations.
Overview

Implementations in accordance with the present disclosure relate to various techniques, methods, schemes and/or solutions pertaining to attempting to establish radio resource control (RRC) connection with respect to apparatus in mobile communications. According to the present disclosure, a number of possible solutions may be implemented separately or jointly. That is, although these possible solutions may be described below separately, two or more of these possible solutions may be implemented in one combination or another.

Regarding the present disclosure, when a User Equipment (UE) attempts to register with a network node, the UE may perform a connecting procedure (e.g., attach procedure, Tracking Area Update (TAU) procedure, registration procedure, etc. ) with the network node. During the connecting procedure, the UE may attempt to establish a Radio Resource Control (RRC) connection with the network node.

In some scenarios, the establishment of RRC connection may be successful. After establishing the RRC connection, the UE may transmit Non-Access Stratum (NAS) messages (e.g., attach request, registration request, etc. ) to the network node. The network node may process the NAS messages, perform authentication, security procedures, and session setup, then respond with appropriate NAS messages to complete network registration.

In some scenarios, the establishment of the RRC connection may fail. Due to the failure of establishing the RRC connection, a NAS layer (i.e., NAS functionality) of the UE may receive a lower layer failure associated with establishing the RRC connection. In an event that the UE determines the lower layer failure occurs (i.e., the NAS layer of the UE receives the lower layer failure) , the UE may increment an attempt counter.

Next, the UE may determine whether the attempt counter is less than a threshold. In some scenarios, when the UE determines that the attempt counter is less than the threshold, the UE may then start a first timer. The UE may attempt to establish the RRC connection in an event that the first timer expires. In some scenarios, when the UE determines that the attempt counter is not less than the threshold (i.e., equal to or greater than the threshold) , the UE may then start a second timer. The UE may attempt to establish the RRC connection in an event that the second timer expires.

Accordingly, based on different network scenarios, at least one of the threshold, the first timer, and the second timer may be dynamically configured, thereby significantly enhancing the delay performance and flexibility of RRC connection establishment.

FIG. 1 illustrates an example scenario 100 under schemes in accordance with implementations of the present disclosure. Scenario 100 involves at least one network node and a UE, which may be a part of a wireless communication network (e.g., an LTE network, a 5G/NR network, an IoT network or a 6G network) . Scenario 100 illustrates the current network framework. The UE may attempt to connect to the network side. The network side may comprise one or more than one network nodes.

In some embodiments, when a UE attempts to register with the network node, the UE may perform a connecting procedure (e.g., attach procedure, TAU procedure, registration procedure, etc. ) with the network node. At the beginning of the connecting procedure, the UE may: (1) set (i.e., initialize) an attempt counter, which may be used to track the number of RRC connection establishment attempts, to zero; and/or (2) determine a threshold representing a maximum number of RRC connection retries. Then, the UE may attempt to establish an RRC connection with the network node.

In some implementations, after the UE attempts to establish the RRC connection with the network node, the establishment of RRC connection may be failed or successful.

In some implementations, the establishment of the RRC connection may fail. Due to the failure of establishing the RRC connection, a NAS layer (i.e., NAS functionality) of the UE may receive a lower layer failure associated with establishing the RRC connection (e.g., the NAS layer may receive an RRC connection failure from the lower RRC layer) . In an event that the UE determines the lower layer failure occurs (i.e., the NAS layer of the UE receives the lower layer failure) , the UE may increment the attempt counter.

In some implementations, the UE may determine whether the attempt counter is less than a threshold. Based on the determination, the UE may selectively initiate different timers corresponding to different results, thereby controlling the timing of subsequent RRC connection establishment attempts in accordance with network conditions.

In some cases, when the UE determines that the attempt counter is less than the threshold, the UE may then start a first timer. The UE may attempt to establish the RRC connection in an event that the first timer expires. In other words, the UE may not attempt to establish the RRC connection until the first timer has expired. This establishment of RRC connection may be successful or failed so that the UE may repeatedly: (1) increment the attempt counter; and (2) determine whether the attempt counter is less than the threshold.

In some cases, when the UE determines that the attempt counter is not less than the threshold (i.e., equal to or greater than the threshold) , the UE may then start a second timer. The UE may attempt to establish the RRC connection in an event that the second timer expires. In other words, the UE may not attempt to establish the RRC connection until the second timer has expired. This establishment of RRC connection may be successful or failed so that the UE may repeatedly: (1) increment the attempt counter; and (2) determine whether the attempt counter is less than the threshold.

In some implementations, the UE may determine that: (1) no lower layer failure occurs at the beginning of connecting procedure, or (2) no additional lower layer failure occurs during repeated attempts to establish the RRC connection, thereby indicating successful RRC connection establishment. Then, the UE may establish the RRC connection with the network node and transmit NAS messages (e.g., an attach request, a registration request, etc. ) to the network node. The network node may receive and process the NAS messages, perform authentication and security procedures, and establish a session. Upon completion of these procedures, the network node may transmit corresponding NAS messages to the UE, thereby facilitating successful network registration and enabling access to network services.

In some implementations, the UE may determine the threshold based on a network condition. For example, based on a network environment complexity (e.g., signal quality, interference, path loss, etc. ) and/or the UE's network service demand level, the UE determines an increased or decreased threshold, thereby adjusting the tolerance for RRC connection establishment attempts to accommodate varying network conditions and service requirements.

In some implementations, the network node may be deployed in a home network, and the RRC connection may be associated with a network access in the home network. In some cases, the home network may include at least one of terrestrial network (TN) and non-terrestrial network (NTN) , and the network access may include at least one of terrestrial access and non-terrestrial access. In some cases, the home network may be a Home Public Land Mobile Network (HPLMN) .

In some implementations, the network node may be a network node in a visited network, and the RRC connection may be associated with a network access in the visited network. In some cases, the visited network may include at least one of TN and NTN, and the network access may include at least one of terrestrial access and non-terrestrial access. In some cases, the visited network may be a Visited Public Land Mobile Network (VPLMN) .

In some implementations, the UE may receive a list of visited networks from the home network. In particular, the home network (e.g., the HPLMN) may provide the UE with a list of visited networks (e.g., a list of VPLMNs) . The UE, such as its NAS layer (i.e., NAS functionality) , may be informed or configured regarding whether a configuration of the first timer, the second timer, and the threshold is applicable in an event that the UE attempts to establish an RRC connection with the visited network included in the list.

In some implementations, the UE may determine the threshold to be greater than 5, for example, 10 to 20, and the first timer may be determined or pre-configured to be shorter than the second timer.

In some implementations, the UE may determine the threshold to be less than 5, for example, 2 to 4, and the first timer may be determined or pre-configured to be longer than the second timer.

FIG. 2A illustrates an example scenario 200A under schemes in accordance with implementations of the present disclosure. Scenario 200A depicts a complete loop of an RRC establishment procedure of the present disclosure. FIG. 2B illustrates an example scenario 200B under schemes in accordance with implementations of the present disclosure. Scenario 200B pertains to operations in which lower layer failures persist.

For example, when the UE attempts to register with a VPLMN network node, the UE performs a connecting procedure with the VPLMN network node. At the beginning of the connecting procedure, the UE: (1) sets (i.e., initializes) an attempt counter to zero; and (2) determines a threshold ‘K’ representing a maximum number of RRC connection retries. Then, the UE attempts to establish an RRC connection with the VPLMN network node.

After the UE attempts to establish the RRC connection with the VPLMN network node, the UE determines whether a lower layer failure occurs. If the UE determines that no lower layer failure occurs, the UE establishes the RRC connection with the VPLMN network node successfully. If the UE determines that a lower layer failure occurs, the UE increments the attempt counter.

Then, the UE determines whether the attempt counter is less than the threshold ‘K’ . If the UE determines that the attempt counter is less than the threshold ‘K’ , the UE starts a first timer and then stops attempting to establish the RRC connection with the VPLMN network node during the first timer. When the first timer expires, the UE attempts to establish the RRC connection with the VPLMN network node. Next, the UE performs the operation of determining whether a lower layer failure occurs and subsequently performs the corresponding operations.

If the UE determines that the attempt counter is not less than the threshold ‘K’ (i.e., the attempt counter is equal to or greater than the threshold ‘K’ ) , the UE starts a second timer and then stops attempting to establish the RRC connection with the VPLMN network node during the second timer. When the second timer expires, the UE attempts to establish the RRC connection with the VPLMN network node if necessary. Next, when the UE attempts to establish the RRC connection with the VPLMN network node after the second timer expires, the UE performs the operation of determining whether a lower layer failure occurs and subsequently performs the corresponding operations. Optionally, within the dotted-line frame, when the UE attempts to establish the RRC connection with the VPLMN network node after the second timer expires, the UE sets (i.e., initializes) the attempt counter to zero. It should be noted that the operation within the dotted-line frame may not be performed in some cases.

FIG. 3 illustrates an example scenario 300 under schemes in accordance with implementations of the present disclosure. In some embodiments, the UE may start a timer in an event that a number of lower layer failures reaches a threshold. The number of lower layer failures may be associated with establishing an RRC connection with a first satellite network node. The UE may stop the timer: (1) in an event that the UE loses the first satellite network node, or (2) in an event that the UE selects a second satellite network node.

More specifically, the UE may continue to receive some messages (e.g., System Information Block (SIB) ) from the first satellite network node. During this period, the UE may attempt to establish the RRC connection with the first satellite network node. The UE may start the timer in the event that the number of lower layer failures associated with the RRC connection reaches the threshold.

In some cases, before the timer expires, if the UE receives no such messages (e.g., SIB) , the UE may determine that the UE loses a satellite cell coverage of the first satellite network node as shown in FIG. 3. Then the UE may stop the timer.

In some cases, before the timer expires, if the UE selects the second satellite network node (i.e., the UE handovers from the first satellite network node to the second satellite network node, or the UE camps on another satellite cell coverage of the second satellite network node as shown in FIG. 3) , the UE may stop the timer.
Illustrative Implementations

FIG. 4 illustrates an example communication system 400 having an example communication apparatus 410 and an example network apparatus 420 in accordance with an implementation of the present disclosure. Each of communication apparatus 410 and network apparatus 420 may perform various functions to implement schemes, techniques, processes and methods described herein pertaining to attempting to establish RRC connection with respect to UE and network apparatus in mobile communications, including scenarios/schemes described above as well as processes 500 and 600 described below.

Communication apparatus 410 may be a part of an electronic apparatus, which may be a UE such as a portable or mobile apparatus, a wearable apparatus, a wireless communication apparatus or a computing apparatus. For instance, communication apparatus 410 may be implemented in a smartphone, a smartwatch, a personal digital assistant, a digital camera, or a computing equipment such as a tablet computer, a laptop computer or a notebook computer. Communication apparatus 410 may also be a part of a machine type apparatus, which may be an IoT, NB-IoT, or IIoT apparatus such as an immobile or a stationary apparatus, a home apparatus, a wire communication apparatus or a computing apparatus. For instance, communication apparatus 410 may be implemented in a smart thermostat, a smart fridge, a smart door lock, a wireless speaker or a home control center. Alternatively, communication apparatus 410 may be implemented in the form of one or more integrated-circuit (IC) chips such as, for example and without limitation, one or more single-core processors, one or more multi-core processors, one or more reduced-instruction set computing (RISC) processors, or one or more complex-instruction-set-computing (CISC) processors. Communication apparatus 410 may include at least some of those components shown in FIG. 4 such as a processor 412, for example. Communication apparatus 410 may further include one or more other components not pertinent to the proposed scheme of the present disclosure (e.g., internal power supply, display device and/or user interface device) , and, thus, such component (s) of communication apparatus 410 are neither shown in FIG. 4 nor described below in the interest of simplicity and brevity.

Network apparatus 420 may be a part of a network apparatus, which may be a network node such as a satellite, a base station, a small cell, a router or a gateway. For instance, network apparatus 420 may be implemented in an eNodeB in an LTE network, in a gNB in a 5G/NR, IoT, NB-IoT or IIoT network or in a satellite or base station in a 6G network. Alternatively, network apparatus 420 may be implemented in the form of one or more IC chips such as, for example and without limitation, one or more single-core processors, one or more multi-core processors, or one or more RISC or CISC processors. Network apparatus 420 may include at least some of those components shown in FIG. 4 such as a processor 422, for example. Network apparatus 420 may further include one or more other components not pertinent to the proposed scheme of the present disclosure (e.g., internal power supply, display device and/or user interface device) , and, thus, such component (s) of network apparatus 420 are neither shown in FIG. 4 nor described below in the interest of simplicity and brevity.

In one aspect, each of processor 412 and processor 422 may be implemented in the form of one or more single-core processors, one or more multi-core processors, or one or more CISC processors. That is, even though a singular term “a processor” is used herein to refer to processor 412 and processor 422, each of processor 412 and processor 422 may include multiple processors in some implementations and a single processor in other implementations in accordance with the present disclosure. In another aspect, each of processor 412 and processor 422 may be implemented in the form of hardware (and, optionally, firmware) with electronic components including, for example and without limitation, one or more transistors, one or more diodes, one or more capacitors, one or more resistors, one or more inductors, one or more memristors and/or one or more varactors that are configured and arranged to achieve specific purposes in accordance with the present disclosure. In other words, in at least some implementations, each of processor 412 and processor 422 is a special-purpose machine specifically designed, arranged and configured to perform specific tasks including attempting to establish RRC connection in a device (e.g., as represented by communication apparatus 410) and a network (e.g., as represented by network apparatus 420) in accordance with various implementations of the present disclosure.

In some implementations, communication apparatus 410 may also include a transceiver 416 coupled to processor 412 and capable of wirelessly transmitting and receiving data. In other words, processor 412 may transceive the data such as configuration, message, signal, information, indicator, etc. via transceiver 416. In some implementations, communication apparatus 410 may further include a memory 414 coupled to processor 412 and capable of being accessed by processor 412 and storing data therein. In some implementations, network apparatus 420 may also include a transceiver 426 coupled to processor 422 and capable of wirelessly transmitting and receiving data. In other words, processor 422 may transceive the data such as configuration, message, signal, information, indicator, etc. via transceiver 426. In some implementations, network apparatus 420 may further include a memory 424 coupled to processor 422 and capable of being accessed by processor 422 and storing data therein. Accordingly, communication apparatus 410 and network apparatus 420 may wirelessly communicate with each other via transceiver 416 and transceiver 426, respectively. To aid better understanding, the following description of the operations, functionalities and capabilities of each of communication apparatus 410 and network apparatus 420 is provided in the context of a mobile communication environment in which communication apparatus 410 is implemented in or as a communication apparatus or a UE and network apparatus 420 is implemented in or as a network node of a communication network.

In some implementations, each of memory 414 and memory 424 may include a type of random-access memory (RAM) such as dynamic RAM (DRAM) , static RAM (SRAM) , thyristor RAM (T-RAM) and/or zero-capacitor RAM (Z-RAM) . Alternatively, or additionally, each of memory 414 and memory 424 may include a type of read-only memory (ROM) such as mask ROM, programmable ROM (PROM) , erasable programmable ROM (EPROM) and/or electrically erasable programmable ROM (EEPROM) . Alternatively, or additionally, each of memory 414 and memory 424 may include a type of non-volatile random-access memory (NVRAM) such as flash memory, solid-state memory, ferroelectric RAM (FeRAM) , magnetoresistive RAM (MRAM) and/or phase-change memory.
Illustrative Processes

FIG. 5 illustrates an example process 500 in accordance with an implementation of the present disclosure. Process 500 may be an example implementation of above scenarios/schemes, whether partially or completely, with respect to attempting to establish RRC connection of the present disclosure. Process 500 may represent an aspect of implementation of features of communication apparatus 410. Process 500 may include one or more operations, actions, or functions as illustrated by one or more of blocks 510 to 540. Although illustrated as discrete blocks, various blocks of process 500 may be divided into additional blocks, combined into fewer blocks, or eliminated, depending on the desired implementation. Moreover, the blocks of process 500 may be executed in the order shown in FIG. 5 or, alternatively, in a different order. Process 500 may be implemented by communication apparatus 410 or any suitable UE or machine type devices. Solely for illustrative purposes and without limitation, process 500 is described below in the context of communication apparatus 410. Process 500 may begin at block 510.

At block 510, process 500 may involve processor 412 of communication apparatus 410 incrementing an attempt counter in an event that a lower layer failure occurs. The lower layer failure may be associated with establishing an RRC connection. Process 500 may proceed from block 510 to block 520.

At block 520, process 500 may involve processor 412 of communication apparatus 410 determining whether the attempt counter is less than a threshold. Process 500 may proceed from block 520 to block 530.

At block 530, process 500 may involve processor 412 of communication apparatus 410 starting a first timer in an event that the attempt counter is less than the threshold or a second timer in an event that the attempt counter is not less than the threshold. Process 500 may proceed from block 530 to block 540.

At block 540, process 500 may involve processor 412 of communication apparatus 410 attempting to establish the RRC connection in an event that the first timer expires or the second timer expires.

In some implementations, process 500 may further involve processor 412 of communication apparatus 410 determining the threshold based on network environment.

In some implementations, process 500 may further involve processor 412 of communication apparatus 410 setting the attempt counter to zero.

In some implementations, the RRC connection may be associated with a network access in a home network or in a visited network.

In some implementations, the network access may include at least one of terrestrial access and non-terrestrial access.

In some implementations, the visited network may include a VPLMN.

In some implementations, process 500 may further involve processor 412 of communication apparatus 410 receiving, via the transceiver 416, a list of visited networks from the home network. The list of visited networks may include the visited network.

In some implementations, process 500 may further involve processor 412 of communication apparatus 410 determining that no additional lower layer failure occurs. Process 500 may further involve processor 412 of communication apparatus 410 establishing the RRC connection.

In some implementations, the threshold may be greater than 5 and the first timer may be shorter than the second timer.

FIG. 6 illustrates an example process 600 in accordance with an implementation of the present disclosure. Process 600 may be an example implementation of above scenarios/schemes, whether partially or completely, with respect to attempting to establish RRC connection of the present disclosure. Process 600 may represent an aspect of implementation of features of communication apparatus 410. Process 600 may include one or more operations, actions, or functions as illustrated by one or more of blocks 610 and 620. Although illustrated as discrete blocks, various blocks of process 600 may be divided into additional blocks, combined into fewer blocks, or eliminated, depending on the desired implementation. Moreover, the blocks of process 600 may be executed in the order shown in FIG. 6 or, alternatively, in a different order. Process 500 may be implemented by communication apparatus 410 or any suitable UE or machine type devices. Solely for illustrative purposes and without limitation, process 600 is described below in the context of communication apparatus 410. Process 600 may begin at block 610.

At block 610, process 600 may involve processor 412 of communication apparatus 410 starting a timer in an event that a number of lower layer failures reaches a threshold. The number of lower layer failures may be associated with establishing an RRC connection with a first satellite network node. Process 600 may proceed from block 610 to block 620.

At block 620, process 600 may involve processor 412 of communication apparatus 410 stopping the timer in an event that the apparatus loses the first satellite network node or in an event that the apparatus selects a second satellite network node.
Additional Notes

The herein-described subject matter sometimes illustrates different components contained within, or connected with, different other components. It is to be understood that such depicted architectures are merely examples, and that in fact many other architectures can be implemented which achieve the same functionality. In a conceptual sense, any arrangement of components to achieve the same functionality is effectively "associated" such that the desired functionality is achieved. Hence, any two components herein combined to achieve a particular functionality can be seen as "associated with" each other such that the desired functionality is achieved, irrespective of architectures or intermedial components. Likewise, any two components so associated can also be viewed as being "operably connected" , or "operably coupled" , to each other to achieve the desired functionality, and any two components capable of being so associated can also be viewed as being "operably couplable" , to each other to achieve the desired functionality. Specific examples of operably couplable include but are not limited to physically mateable and/or physically interacting components and/or wirelessly interactable and/or wirelessly interacting components and/or logically interacting and/or logically interactable components.

Further, with respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity.

Moreover, it will be understood by those skilled in the art that, in general, terms used herein, and especially in the appended claims, e.g., bodies of the appended claims, are generally intended as “open” terms, e.g., the term “including” should be interpreted as “including but not limited to, ” the term “having” should be interpreted as “having at least, ” the term “includes” should be interpreted as “includes but is not limited to, ” etc. It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases "at least one" and "one or more" to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles "a" or "an" limits any particular claim containing such introduced claim recitation to implementations containing only one such recitation, even when the same claim includes the introductory phrases "one or more" or "at least one" and indefinite articles such as "a" or "an, " e.g., “a” and/or “an” should be interpreted to mean “at least one” or “one or more; ” the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should be interpreted to mean at least the recited number, e.g., the bare recitation of "two recitations, " without other modifiers, means at least two recitations, or two or more recitations. Furthermore, in those instances where a convention analogous to “at least one of A, B, and C, etc. ” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention, e.g., “a system having at least one of A, B, and C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc. In those instances where a convention analogous to “at least one of A, B, or C, etc. ” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention, e.g., “a system having at least one of A, B, or C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc. It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase “A or B” will be understood to include the possibilities of “A” or “B” or “A and B. ”

From the foregoing, it will be appreciated that various implementations of the present disclosure have been described herein for purposes of illustration, and that various modifications may be made without departing from the scope and spirit of the present disclosure. Accordingly, the various implementations disclosed herein are not intended to be limiting, with the true scope and spirit being indicated by the following claims.

Claims

A method, comprising:

incrementing, by a processor of an apparatus, an attempt counter in an event that a lower layer failure occurs, wherein the lower layer failure is associated with establishing a radio resource control (RRC) connection;

determining, by the processor, whether the attempt counter is less than a threshold;

starting, by the processor, a first timer in an event that the attempt counter is less than the threshold or a second timer in an event that the attempt counter is not less than the threshold; and

attempting, by the processor, to establish the RRC connection in an event that the first timer expires or the second timer expires.
The method of Claim 1, further comprising:

determining, by the processor, the threshold based on a network condition.
The method of Claim 1, further comprising:

setting, by the processor, the attempt counter to zero.
The method of Claim 1, wherein the RRC connection is associated with a network access in a home network or in a visited network.
The method of Claim 4, wherein the network access includes at least one of terrestrial access and non-terrestrial access.
The method of Claim 4, wherein the visited network includes a Visited Public Land Mobile Network (VPLMN) .
The method of Claim 4, further comprising:

receiving, by the processor, a list of visited networks from the home network, wherein the list of visited networks includes the visited network.
The method of Claim 1, further comprising:

determining, by the processor, that no additional lower layer failure occurs; and

establishing, by the processor, the RRC connection.
The method of Claim 1, wherein the threshold is greater than 5.
The method of Claim 1, wherein the first timer is shorter than the second timer.
An apparatus, comprising:

a transceiver which, during operation, wirelessly communicates with a wireless network; and

a processor communicatively coupled to the transceiver such that, during operation, the processor performs operations comprising:

incrementing an attempt counter in an event that a lower layer failure occurs, wherein the lower layer failure is associated with establishing a radio resource control (RRC) connection;

determining whether the attempt counter is less than a threshold;

starting a first timer in an event that the attempt counter is less than the threshold or a second timer in an event that the attempt counter is not less than the threshold; and

attempting to establish the RRC connection in an event that the first timer expires or the second timer expires.
The apparatus of Claim 11, wherein, during operation, the processor further performs operations comprising:

determining the threshold based on a network environment.
The apparatus of Claim 11, wherein, during operation, the processor further performs operations comprising:

setting the attempt counter to zero.
The apparatus of Claim 11, wherein the RRC connection is associated with a network access in a home network or in a visited network.
The apparatus of Claim 14, wherein the network access includes at least one of terrestrial access and non-terrestrial access.
The apparatus of Claim 14, wherein the visited network includes a Visited Public Land Mobile Network (VPLMN) .
The apparatus of Claim 14, wherein, during operation, the processor further performs operations comprising:

receiving, via the transceiver, a list of visited networks from the home network, wherein the list of visited networks includes the visited network.
The apparatus of Claim 11, wherein, during operation, the processor further performs operations comprising:

determining that no additional lower layer failure occurs; and

establishing the RRC connection.
The apparatus of Claim 11, wherein the threshold is greater than 5 and the first timer is shorter than the second timer.
A method, comprising:

starting, by a processor of an apparatus, a timer in an event that a number of lower layer failures reaches a threshold, wherein the number of lower layer failures is associated with establishing a Radio Resource Control (RRC) connection with a first satellite network node; and

stopping, by the processor, the timer in an event that the apparatus loses the first satellite network node or in an event that the apparatus selects a second satellite network node.