WO2024222758A1

WO2024222758A1 - Methods and apparatuses for enhancements on non-access stratum procedure with a satellite in store-and-forward operation mode

Info

Publication number: WO2024222758A1
Application number: PCT/CN2024/089648
Authority: WO
Inventors: Marko NIEMI
Original assignee: MediaTek Singapore Pte Ltd; MediaTek Inc
Current assignee: MediaTek Singapore Pte Ltd; MediaTek Inc
Priority date: 2023-04-24
Filing date: 2024-04-24
Publication date: 2024-10-31
Anticipated expiration: 2025-10-24
Also published as: CN120982154A

Abstract

Various solutions for enhancements on non-access stratum (NAS) procedures with a satellite in store-and-forward (S&F) operation mode are described. An apparatus may transmit a request message for initiating a NAS procedure to a network node of a wireless network. The network node includes a first satellite. Then, the apparatus may receive a response message corresponding to the NAS procedure from the network node. The response message includes at least one of a first indication that the NAS procedure is not completed and a second indication for assisting the apparatus on subsequent re-attempts or resumptions of the NAS procedure.

Description

METHODS AND APPARATUSES FOR ENHANCEMENTS ON NON-ACCESS STRATUM PROCEDURE WITH A SATELLITE IN STORE-AND-FORWARD OPERATION MODE

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. 63/497, 765, filed 24 April 2023, the content of which herein being incorporated by reference in its entirety.

TECHNICAL FIELD

The present disclosure is generally related to mobile communications and, more particularly, to enhancements on non-access stratum (NAS) procedures with a satellite in store-and-forward (S&F) operation mode.

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 3^rd Generation Partnership Project (3GPP) Release 17, non-terrestrial network (NTN) is introduced as a terminal-satellite direct communication technology based on the Long-Term Evolution (LTE) or New Radio (NR) interface. With the integration of satellite network and ground cellular network (e.g., 4^th/5^th generation (4/5G) network) , NTN may provide ubiquitous coverage without being restricted by terrain and landform. Based on the altitudes located above the earth surface, satellites can be categorized into geostationary orbit (GEO) satellites, medium earth orbit (MEO) satellites, and low earth orbit (LEO) satellites. FIG. 1 illustrates different satellite orbits in satellite communication. GEO satellites are typically positioned at approximately 35786 kilometer (km) above the earth surface. LEO satellites typically orbit around or below 2000 km above the earth surface. MEO satellites typically orbit at altitudes higher than LEO but lower than GEO, ranging from around 2000 km to 35786 km above the earth surface.

A constellation generally refers to a group of satellites orbiting at a specific altitude. For example, a sparse LEO constellation may include tens of satellites to provide a certain level of satellite coverage in a way that it cannot offer continuous connectivity via the satellites to the ground stations (GS) . To cope with the lack of continuous connectivity, it is discussed in 3GPP that a satellite of a sparse LEO constellation may be equipped with base station (BS) and core network (CN) elements, allowing the satellite to offer a user equipment (UE) with partial CN services and uplink (UL) and downlink (DL) data services, e.g., by implementing a store-and-forward (S&F) type of functionality in the satellite. However, a challenge for the S&F operation is that for security and/or capacity reasons, the satellite cannot carry on all network functions, such as home subscriber server (HSS) functions for managing subscriber information, and/or security functions for establishing NAS/AS security between the UE and the network. As a result, the S&F solution will impact existing NAS procedures, such as initial registration procedure in 5G and attach procedure in 4G, due to incomplete network functions in the satellite. Accordingly, how to enhance the NAS procedures with a satellite in the S&F operation mode has become an important issue for newly developed wireless communication systems.

Therefore, there is a need to provide proper schemes and designs to solve this issue.

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 issue pertaining to enhancements on NAS procedures with a satellite in the S&F operation mode.

In one aspect, a method may involve an apparatus transmitting a request message for initiating a NAS procedure to a network node of a wireless network, wherein the network node comprises a first satellite. The method may also involve the apparatus receiving a response message corresponding to the NAS procedure from the network node, wherein the response message comprises at least one of a first indication that the NAS procedure is not completed and a second indication for assisting the apparatus on subsequent re-attempts or resumptions of the NAS procedure.

In one aspect, an apparatus may comprise a transceiver which, during operation, wirelessly communicates with a network node of a wireless network. The apparatus may also comprise a processor communicatively coupled to the transceiver. The processor, during operation, may perform operations comprising transmitting, via the transceiver, a request message for initiating a NAS procedure to the network node, wherein the network node comprises a first satellite. The processor may also perform operations comprising receiving, via the transceiver, a response message corresponding to the NAS procedure from the network node, wherein the response message comprises at least one of a first indication that the NAS procedure is not completed and a second indication for assisting the apparatus on subsequent re-attempts or resumptions of the NAS procedure.

In one aspect, a method may involve a network node receiving a request message for initiating a NAS procedure from an apparatus, wherein the network node comprises a first satellite. The method may also involve the network node transmitting a response message corresponding to the NAS procedure to the apparatus, wherein the response message comprises at least one of a first indication that the NAS procedure is not completed and a second indication for assisting the apparatus on subsequent re-attempts or resumptions of the NAS procedure.

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) , beyond 5G (B5G) , 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 different satellite orbits in satellite communication.

FIG. 2 is a diagram depicting an example scenario of a communication environment in which various solutions and schemes in accordance with the present disclosure may be implemented.

FIGs. 3A and 3B show a diagram depicting an example scenario of an enhanced NAS procedure with a satellite in the S&F operation mode in accordance with an implementation of the present disclosure.

FIG. 4 is a diagram depicting an example scenario of an evolved packet system (EPS) mobility management (EMM) or 5G mobility management (5GMM) information element (IE) for carrying the re-attempt assistance information in accordance with an implementation of the present disclosure.

FIG. 5 is a block diagram of an example communication system 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.

FIG. 7 is a flowchart of another 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 enhancements on NAS procedures with a satellite in the S&F operation mode. 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.

FIG. 2 illustrates an example scenario 200 of a communication environment in which various solutions and schemes in accordance with the present disclosure may be implemented. Scenario 200 involves a UE 210 in wireless communication with a network 220 (e.g., a wireless network including an NTN and a TN) via a terrestrial network node 222 (e.g., an evolved Node-B (eNB) , a Next Generation Node-B (gNB) , or a transmission/reception point (TRP) ) and/or a non-terrestrial network node 224 (e.g., a satellite) . The UE 210 may be an IoT device such as an NB-IoT UE or an eMTC UE (e.g., a bandwidth reduced low complexity (BL) UE or a coverage enhancement (CE) UE) . The non-terrestrial network node 224 may operate in the S&F operation mode to form a satellite cell for wireless communication with the UE 210 through the feeder link to the GS, e.g., the terrestrial network node 222. In some implementations, the non-terrestrial network node 224 may include one or more satellites of a (sparse LEO) constellation, and each satellite may be equipped with some eNB/gNB and CN functions/elements (e.g., without the HSS functions for managing subscriber information and/or the security functions for establishing NAS/AS security between the UE 210 and the network 220) to offer the UE 210 with partial CN services and UL and DL data service by implementing the S&F type of functionality in the satellite. In such communication environment, the UE 210, the network 220, the terrestrial network node 222, and the non-terrestrial network node 224 may implement various schemes pertaining to enhancements on NAS procedures with a satellite in the S&F operation mode in accordance with the present disclosure, as described below. It is noteworthy that, while the various proposed schemes may be individually or separately described below, in actual implementations some or all of the proposed schemes may be utilized or otherwise implemented jointly. Of course, each of the proposed schemes may be utilized or otherwise implemented individually or separately.

In the present disclosure, NTN refers to a network that uses radio frequency (RF) and information processing resources carried on high, medium and low orbit satellites or other high-altitude communication platforms to provide communication services for UEs. According to the load capacity on the satellite, there are two typical scenarios, namely: transparent payload and regenerative payload. In transparent payload mode, the satellite does not process the signal and waveform in the communication service but, rather, only functions as an RF amplifier to forward data. In regenerative payload mode, the satellite, other than RF amplification, also has the processing capabilities of modulation/demodulation, coding/decoding, switching, routing and so on.

Due to that the satellite may not carry on all network functions, some impacts to the existing NAS procedures may be incurred. For example, if a new subscriber (e.g., a UE) is performing an initial registration/attach procedure with a satellite which is currently lacking access to GS, the initial registration/attach procedure would need to be divided in two or more phases. In the first phase (e.g., first fly-over) , the UE is allowed to start the initial registration/attach procedure with the satellite identifying the UE. In the second phase (e.g., a second fly-over after the UE information is uploaded to the satellite) , the UE is allowed to start the initial registration/attach procedure again to complete the procedure. However, in 3GPP, the details of the NAS procedures with a satellite in the S&F operation mode have not been fully discussed yet.

In view of the above, the present disclosure proposes a number of schemes pertaining to enhancements on NAS procedures with a satellite in the S&F operation mode. According to the schemes of the present disclosure, a UE may transmit a request message (e.g., an ATTACH REQUEST message, or a REGISTRATION REQUEST message) for initiating a NAS procedure (e.g., an attach procedure in LTE system, or an initial registration procedure in NR system) to a network node of a wireless network, wherein the network node includes a satellite operating in the S&F operation mode. Then, the UE may receive a response message corresponding to the NAS procedure from the network node, wherein the response message includes at least one of a first indication (e.g., a reject cause) that the NAS procedure is not completed and a second indication for assisting the UE on subsequent re-attempts or resumptions of the NAS procedure. After that, the UE may suspend/terminate the NAS procedure based on the first indication, and re-attempt/resume the NAS procedure based on the second indication. On the other hand, for a network node including a satellite operating in the S&F operation mode, it may receive the request message for initiating the NAS procedure from the UE. Then, the network node may transmit the response message corresponding to the NAS procedure to the UE, wherein the response message includes at least one of the first indication that the NAS procedure is not completed and the second indication for assisting the UE on subsequent re-attempts or resumptions of the NAS procedure. Accordingly, by applying the schemes of the present disclosure, the NAS procedures with a satellite in the S&F operation mode may be enhanced to allow the NAS procedures to be properly handled and completed successfully.

FIGs. 3A and 3B illustrate an example scenario 300 of an enhanced NAS procedure with a satellite in the S&F operation mode in accordance with an implementation of the present disclosure. Scenario 300 involves a UE in wireless communication with a multi-satellite (IoT) NTN. It is assumed that, initially, the UE is switched on and needs to register with the network, but the (terrestrial) home public land mobile network (PLMN) of the UE is not found and the UE starts the search for a satellite cell. In step 301, the first satellite (denoted as SAT#i) comes within the communication range of the UE, i.e., the cell of SAT#i is detected by the UE. The UE may acquire, among others, the PLMN and the two-line element sets (TLEs) of multiple satellites of the constellation (e.g., from system information block type 32 (SIB32) ) . The UE may also learn from system information block type 31 (SIB31) or SIB32 that the satellite cell is operating in the S&F operation mode. In step 302, the UE initiates the initial registration/attach procedure by transmitting a REGISTRATION/ATTACH REQUEST message. In one example, within the REGISTRATION/ATTACH REQUEST message, the UE may include its capability information indicating the UE’s ability to handle S&F operations (e.g., by an “S&F feature supported” flag) .

In step 303, the first satellite rejects the initial registration/attach procedure because the UE’s subscription data, such as E-UTRAN Authentication Vector (AV) , is absent on board the satellite due to the lack of a currently active feeder link to the GS for subscription data retrieval during this satellite pass. Specifically, the first satellite rejects the initial registration/attach procedure by transmitting a REGISTRATION/ATTACH REJECT message to the UE, and the REGISTRATION/ATTACH REJECT message includes at least a new reject cause (e.g., for indicating that the NAS procedure is not completed due to S&F operation) and a re-attempt assistance information (i.e., an indication for assisting the UE on subsequent re-attempts or resumptions of the NAS procedure) . In this scenario, the re-attempt assistance information includes a value of a timer for indicating when the UE is allowed to re-attempt or resume the NAS procedure.

In step 304, the UE suspends/terminates the initial registration/attach procedure, and starts the timer with the value and the UE is not allowed to re-attempt or resume the NAS procedure before the timer expires. Next, in step 305, the second satellite (denoted as SAT#j) comes within the communication range of the UE. Like the first satellite described in step 303, the second satellite is assumed to be operating in the S&F operation mode and have no subscription information (e.g. E-UTRAN AVs) on board either to be able to resume/complete the attach registration with the UE. When detecting the cell of the second satellite, the UE may identify that this satellite cell belongs to the same PLMN as the cell where it previously attempted the initial registration/attach procedure, and learn from broadcast system information that the second satellite is operating in S&F mode. In this scenario, the UE does not trigger re-attempt or resumption of the initial registration/attach procedure because the second satellite is operating in the S&F operation mode and the timer has not yet expired.

In step 306, the timer expires on the UE. From this point on, the UE knows that the initial registration/attach procedure can be re-attempted or resumed in any upcoming satellite cell of the PLMN. Subsequently, in step S307, the third satellite (denoted as SAT#k) comes within the communication range of the UE. In step 308, responsive to detecting the cell of the third satellite after the timer expires, the UE re-attempts or resumes the initial registration/attach procedure in the third satellite since that the timer is already expired. Specifically, the UE re-attempts or resumes the initial registration/attach procedure by transmitting a REGISTRATION/ATTACH REQUEST message. It is assumed that at some point before step 308, the first satellite gets connected to the GS via the feeder link, such that the first satellite may exchange information with the ground network to obtain the UE’s subscription information (e.g. E-UTRAN AVs) . In addition, it is assumed that at some point before step 308, the third satellite also gets connected to the GS via the feeder link and the E-UTRAN AVs for the subscriber/UE are also uploaded to the third satellite, given that the third satellite is expected to fly over the area where the UE may re-attempt/resume the initial registration/attach procedure after the timer expires.

In step 309, the authentication and security setup processes are performed and completed successfully, given that the third satellite has the UE’s subscription information. In step 310, the third satellite accepts the initial registration/attach procedure by transmitting a REGISTRATION/ATTACH ACCEPT message to the UE. In step 311, the UE replies to the third satellite with a REGISTRATION/ATTACH COMPLETE message, and the initial registration/accept procedure is completed successfully. After that, the UE is able to obtain UL/DL data services from the multi-satellite (IoT) NTN.

In some implementations, the re-attempt assistance information may include/indicate at least one of the following: (i) a value of the timer for indicating when the UE is allowed to re-attempt or resume the NAS procedure; (ii) a number of satellites in sequence that the UE needs to wait before re-attempting or resuming the NAS procedure; and (iii) a satellite identifier (ID) for indicating in which satellite the UE is allowed to re-attempt or resume the NAS procedure. In one example, if the re-attempt assistance information indicates a number of satellites in sequence that the UE needs to wait before re-attempting or resuming the NAS procedure, the UE may determine to re-attempt or resume the NAS procedure only in a satellite with the number of satellites next to the satellite where the NAS procedure is rejected. For instance, if the EMM/5GMM IE indicates value 1, it means that the next satellite can serve the UE to complete the NAS procedure; if the EMM/5GMM IE indicates value 3, it means that the third satellite after the current satellite can serve the UE to complete the NAS procedure; or if the EMM/5GMM IE indicates value 4, it means that the UE should re-attempt or resume the NAS procedure when the 4^th satellite after the current satellite becomes available. In another example, if the re-attempt assistance information includes a satellite ID indicating a satellite that can serve the UE to complete the NAS procedure, the UE may determine the satellite ID of a detected/available satellite based on the satellite assistance information (e.g., ephemeris data or satellite in-coverage or out-of-coverage information) in the broadcast system information of the detected/available satellite, and only re-attempt or resume the NAS procedure when the satellite ID in the satellite assistance information matches with the satellite ID in the re-attempt assistance information. The broadcast system information may include at least one of a SIB31, a SIB 31-narrowband (SIB31-NB) , a SIB32, and a SIB32-NB.

FIG. 4 illustrates an example scenario 400 of an EMM/5GMM IE for carrying the re-attempt assistance information in accordance with an implementation of the present disclosure. Scenario 400 involves a general packet radio service (GPRS) timer IE (re) used to carry the re-attempt assistance information. Part (A) of FIG. 4 depicts the format of the GPRS timer IE, which includes 2 octets in total. Part (B) of FIG. 4 depicts the representations for the coded values of the bits in the second octet of the GPRS timer IE. As shown in part (B) of FIG. 4, in the case where the re-attempt assistance information including a timer value, bits 6 to 8 in the second octet of the GPRS timer IE defines the timer value unit for the GPRS timer, and bits 5 to 1 in the second octet of the GPRS timer IE can be coded to provide the re-attempt assistance information. Alternatively, in the cases where the re-attempt assistance information indicating a number of satellites or including a satellite ID, the entire second octet of the GPRS timer IE can be coded to provide the re-attempt assistance information. In one example, if octet 2 of the GPRS timer IE (or another corresponding timer IE) is set to ’ 0000 0111’ (i.e., equals to decimal value 7) , the UE may re-attempt/resume the NAS procedure with the 7^th satellite (in sequence) that becomes available at the UE’s location. In another example of the re-attempt assistance information including a satellite ID, if octet 2 of the GPRS timer IE (or another corresponding timer IE) is set to ’ 0111 0101’ (i.e., equals to decimal value 117) , the UE may re-attempt/resume the NAS procedure when it is in coverage of satellite#117.

It is noteworthy that even though in FIG. 4, the GPRS timer IE is used as an exemplary EMM/5GMM IE to carry the re-attempt assistance information, other EMM/5GMM IEs such as a new IE or another existing IE can be used instead to carry the re-attempt assistance information, and the present disclosure is not limited thereto.

Illustrative Implementations

FIG. 5 illustrates an example communication system 500 having an example communication apparatus 510 and an example network apparatus 520 in accordance with an implementation of the present disclosure. Each of communication apparatus 510 and network apparatus 520 may perform various functions to implement schemes, techniques, processes and methods described herein pertaining to enhancements on NAS procedures with a satellite in the S&F operation mode, including scenarios/schemes described above as well as processes 600 and 700 described below.

Communication apparatus 510 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 510 may be implemented in a smartphone, a smartwatch, a personal digital assistant, an electronic control unit (ECU) in a vehicle, a digital camera, or a computing equipment such as a tablet computer, a laptop computer or a notebook computer. Communication apparatus 510 may also be a part of a machine type apparatus, which may be an IoT, NB-IoT, IIoT, BL, or CE UE such as an immobile or a stationary apparatus, a home apparatus, a roadside unit (RSU) , a wire communication apparatus or a computing apparatus. For instance, communication apparatus 510 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 510 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 510 may include at least some of those components shown in FIG. 5 such as a processor 512, for example. Communication apparatus 510 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 510 are neither shown in FIG. 5 nor described below in the interest of simplicity and brevity.

Network apparatus 520 may be a part of an electronic apparatus, which may be a network node such as a satellite, a BS, a small cell, a router or a gateway of an (IoT) NTN. For instance, network apparatus 520 may be implemented in a satellite operating in the S&F operation mode. Alternatively, network apparatus 520 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 520 may include at least some of those components shown in FIG. 5 such as a processor 522, for example. Network apparatus 520 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 520 are neither shown in FIG. 5 nor described below in the interest of simplicity and brevity.

In one aspect, each of processor 512 and processor 522 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 “aprocessor” is used herein to refer to processor 512 and processor 522, each of processor 512 and processor 522 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 512 and processor 522 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 512 and processor 522 is a special-purpose machine specifically designed, arranged and configured to perform specific tasks, including enhancements on NAS procedures with a satellite in the S&F operation mode, in a UE (e.g., as represented by communication apparatus 510) and a network node (e.g., as represented by network apparatus 520) in accordance with various implementations of the present disclosure.

In some implementations, communication apparatus 510 may also include a transceiver 516 coupled to processor 512 and capable of wirelessly transmitting and receiving data. In some implementations, transceiver 516 may be capable of wirelessly communicating with different types of UEs and/or wireless networks of different radio access technologies (RATs) . In some implementations, transceiver 516 may be equipped with a plurality of antenna ports (not shown) such as, for example, four antenna ports. That is, transceiver 516 may be equipped with multiple transmit antennas and multiple receive antennas for multiple-input multiple-output (MIMO) wireless communications. In some implementations, network apparatus 520 may also include a transceiver 526 coupled to processor 522. Transceiver 526 may include a transceiver capable of wirelessly transmitting and receiving data. In some implementations, transceiver 526 may be capable of wirelessly communicating with different types of UEs of different RATs. In some implementations, transceiver 526 may be equipped with a plurality of antenna ports (not shown) such as, for example, four antenna ports. That is, transceiver 526 may be equipped with multiple transmit antennas and multiple receive antennas for MIMO wireless communications.

In some implementations, communication apparatus 510 may further include a memory 514 coupled to processor 512 and capable of being accessed by processor 512 and storing data therein. In some implementations, network apparatus 520 may further include a memory 524 coupled to processor 522 and capable of being accessed by processor 522 and storing data therein. Each of memory 514 and memory 524 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 514 and memory 524 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 514 and memory 524 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.

Each of communication apparatus 510 and network apparatus 520 may be a communication entity capable of communicating with each other using various proposed schemes in accordance with the present disclosure. For illustrative purposes and without limitation, a description of capabilities of communication apparatus 510, as a UE (e.g., a IoT UE such as an NB-IoT UE or a BL/CE UE) , and network apparatus 520, as a network node (e.g., a satellite) , is provided below.

Under certain proposed schemes in accordance with the present disclosure with respect to enhancements on NAS procedures with a satellite in the S&F operation mode, processor 512 of communication apparatus 510 may transmit, via transceiver 516, a request message for initiating a NAS procedure to network apparatus 520, wherein network apparatus 520 includes a first satellite. Then, processor 512 may receive, via transceiver 516, a response message corresponding to the NAS procedure from network apparatus 520, wherein the response message comprises at least one of a first indication that the NAS procedure is not completed and a second indication for assisting communication apparatus 510 on subsequent re-attempts or resumptions of the NAS procedure.

In some implementations, processor 512 may also suspend or terminate the NAS procedure based on the first indication, and re-attempt or resume the NAS procedure based on the second indication.

In some implementations, the first indication may be a reject cause.

In some implementations, first satellite may be operating in an S&F operation mode.

In some implementations, the second indication may include a value of a timer for indicating when communication apparatus 510 is allowed to re-attempt or resume the NAS procedure. Additionally, processor 512 may also start the timer with the value responsive to receiving the response message, wherein the re-attempting or resuming of the NAS procedure is performed after the timer expires.

In some implementations, the second indication may indicate a number of satellites in sequence that communication apparatus 510 needs to wait before re- attempting or resuming the NAS procedure. Additionally, processor 512 may also determine a second satellite with the number of satellites next to the first satellite, wherein the re-attempting or resuming of the NAS procedure is performed in an event that a second satellite is available at a location of communication apparatus 510.

In some implementations, processor 512 may also receive broadcast system information from network apparatus 520, wherein the broadcast system information includes satellite assistance information and the second satellite is determined based on the satellite assistance information.

In some implementations, the broadcast system information may include a SIB31, a SIB31-NB, a SIB32, or a SIB32-NB.

In some implementations, the satellite assistance information may include ephemeris data or satellite in-coverage or out-of-coverage information.

In some implementations, the second indication may include a satellite ID for indicating in which satellite communication apparatus 510 is allowed to re-attempt or resume the NAS procedure, and the re-attempting or resuming of the NAS procedure is performed in an event that a second satellite associated with the satellite ID is available at a location of communication apparatus 510.

Under certain proposed schemes in accordance with the present disclosure with respect to enhancements on NAS procedures with a satellite in the S&F operation mode, processor 522 of network apparatus 520 may receive, via transceiver 526, a request message for initiating a NAS procedure from communication apparatus 510, wherein network apparatus 520 includes a first satellite. Then, processor 522 may transmit, via transceiver 526, a response message corresponding to the NAS procedure to communication apparatus 510, wherein the response message includes at least one of a first indication that the NAS procedure is not completed and a second indication for assisting communication apparatus 510 on subsequent re-attempts or resumptions of the NAS procedure.

In some implementations, the first satellite may be operating in an S&F operation mode.

In some implementations, the first indication may be a reject cause, and the second indication may include at least one of the following: (i) a value of a timer for indicating when communication apparatus 510 is allowed to re-attempt or resume the NAS procedure; (ii) a number of satellites in sequence that communication apparatus 510 needs to wait before re-attempting or resuming the NAS procedure; and (iii) a satellite ID for indicating in which satellite communication apparatus 510 is allowed to re-attempt or resume the NAS procedure.

In some implementations, processor 522 may also transmit, via transceiver 526, broadcast system information to communication apparatus 510, wherein the broadcast system information includes satellite assistance information.

In some implementations, the broadcast system information may include a SIB31, a SIB31-NB, a SIB32, or a SIB32-NB, and/or the satellite assistance information may include ephemeris data or satellite in-coverage or out-of-coverage information.

Illustrative Processes

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 enhancements on NAS procedures with a satellite in the S&F operation mode. Process 600 may represent an aspect of implementation of features of communication apparatus 510. 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 600 may be implemented by or in communication apparatus 510 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 510 as a UE and network apparatus 520 as a network node. Process 600 may begin at block 610.

At 610, process 600 may involve processor 512 of communication apparatus 510 transmitting, via transceiver 516, a request message for initiating a NAS procedure to network apparatus 520, wherein network apparatus 520 includes a first satellite. Process 600 may proceed from 610 to 620.

At 620, process 600 may involve processor 512 receiving, via transceiver 516, a response message corresponding to the NAS procedure from network apparatus 520, wherein the response message includes at least one of a first indication that the NAS procedure is not completed and a second indication for assisting communication apparatus 510 on subsequent re-attempts or resumptions of the NAS procedure.

In some implementations, process 600 may further involve processor 512 suspending or terminating the NAS procedure based on the first indication, and re-attempting or resuming the NAS procedure based on the second indication.

In some implementations, the first indication may be a reject cause.

In some implementations, the second indication may include a value of a timer for indicating when communication apparatus 510 is allowed to re-attempt or resume the NAS procedure. Additionally, process 600 may further involve processor 512 starting the timer with the value responsive to receiving the response message, wherein the re-attempting or resuming of the NAS procedure is performed after the timer expires.

In some implementations, the second indication may indicate a number of satellites in sequence that communication apparatus 510 needs to wait before re-attempting or resuming the NAS procedure. Additionally, process 600 may further involve processor 512 determining a second satellite with the number of satellites next to the first satellite, wherein the re-attempting or resuming of the NAS procedure is performed in an event that a second satellite is available at a location of communication apparatus 510.

In some implementations, process 600 may further involve processor 512 receiving, via transceiver 516, broadcast system information from network apparatus 520, wherein the broadcast system information includes satellite assistance information and the second satellite is determined based on the satellite assistance information.

FIG. 7 illustrates an example process 700 in accordance with an implementation of the present disclosure. Process 700 may be an example implementation of above scenarios/schemes, whether partially or completely, with respect to enhancements on NAS procedures with a satellite in the S&F operation mode. Process 700 may represent an aspect of implementation of features of network apparatus 520. Process 700 may include one or more operations, actions, or functions as illustrated by one or more of blocks 710 and 720. Although illustrated as discrete blocks, various blocks of process 700 may be divided into additional blocks, combined into fewer blocks, or eliminated, depending on the desired implementation. Moreover, the blocks of process 700 may be executed in the order shown in FIG. 7 or, alternatively, in a different order. Process 700 may be implemented by or in network apparatus 520 as well as any variations thereof. Solely for illustrative purposes and without limitation, process 700 is described below in the context of communication apparatus 510 as a UE and network apparatus 520 as a network node. Process 700 may begin at block 710.

At 710, process 700 may involve processor 522 of network apparatus 520 receiving, via transceiver 526, a request message for initiating a NAS procedure from communication apparatus 510, wherein network apparatus 520 includes a first satellite. Process 700 may proceed from 710 to 720.

At 720, process 700 may involve processor 522 transmitting, via transceiver 526, a response message corresponding to the NAS procedure to communication apparatus 510, wherein the response message includes at least one of a first indication that the NAS procedure is not completed and a second indication for assisting communication apparatus 510 on subsequent re-attempts or resumptions of the NAS procedure.

In some implementations, the first indication may be a reject cause.

In some implementations, the second indication may include a value of a timer for indicating when communication apparatus 510 is allowed to re-attempt or resume the NAS procedure.

In some implementations, the second indication may indicate a number of satellites in sequence that communication apparatus 510 needs to wait before re-attempting or resuming the NAS procedure.

In some implementations, process 700 may further involve processor 522 transmitting, via transceiver 526, broadcast system information to communication apparatus 510, wherein the broadcast system information includes satellite assistance information.

In some implementations, the second indication may include a satellite ID for indicating in which satellite communication apparatus 510 is allowed to re-attempt or resume the NAS procedure.

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., “asystem 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., “asystem 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:

transmitting, by a processor of an apparatus, a request message for initiating a non-access stratum (NAS) procedure to a network node of a wireless network, wherein the network node comprises a first satellite; and

receiving, by the processor, a response message corresponding to the NAS procedure from the network node, wherein the response message comprises at least one of a first indication that the NAS procedure is not completed and a second indication for assisting the apparatus on subsequent re-attempts or resumptions of the NAS procedure.
The method of claim 1, further comprising:

suspending or terminating, by the processor, the NAS procedure based on the first indication; and

re-attempting or resuming, by the processor, the NAS procedure based on the second indication.
The method of Claim 1, wherein the first indication is a reject cause.
The method of Claim 1, wherein the first satellite is operating in a store-and-forward operation mode.
The method of Claim 1, wherein the second indication comprises a value of a timer for indicating when the apparatus is allowed to re-attempt or resume the NAS procedure, and the method further comprises:

starting, by the processor, the timer with the value responsive to receiving the response message,

wherein the re-attempting or resuming of the NAS procedure is performed after the timer expires.
The method of Claim 1, wherein the second indication indicates a number of satellites in sequence that the apparatus needs to wait before re-attempting or resuming the NAS procedure, and the method further comprises:

determining, by the processor, a second satellite with the number of satellites next to the first satellite,

wherein the re-attempting or resuming of the NAS procedure is performed in an event that a second satellite is available at a location of the apparatus.
The method of Claim 6, further comprising:

receiving, by the processor, broadcast system information from the network node, wherein the broadcast system information comprises satellite assistance information comprising ephemeris data or satellite in-coverage or out-of-coverage information, and

wherein the second satellite is determined based on the satellite assistance information.
The method of Claim 1, wherein the second indication comprises a satellite identifier (ID) for indicating in which satellite the apparatus is allowed to re-attempt or resume the NAS procedure, and the re-attempting or resuming of the NAS procedure is performed in an event that a second satellite associated with the satellite ID is available at a location of the apparatus.
An apparatus, comprising:

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

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

transmitting, via the transceiver, a request message for initiating a non-access stratum (NAS) procedure to the network node, wherein the network node comprises a first satellite; and

receiving, via the transceiver, a response message corresponding to the NAS procedure from the network node, wherein the response message comprises at least one of a first indication that the NAS procedure is not completed and a second indication for assisting the apparatus on subsequent re-attempts or resumptions of the NAS procedure.
The apparatus of Claim 9, wherein, during operation, the processor further performs operations comprising:

suspending or terminating the NAS procedure based on the first indication; and

re-attempting or resuming the NAS procedure based on the second indication.
The apparatus of Claim 9, wherein the first indication is a reject cause.
The apparatus of Claim 9, wherein the first satellite is operating in a store-and-forward operation mode.
The apparatus of Claim 9, wherein the second indication comprises a value of a timer for indicating when the apparatus is allowed to re-attempt or resume the NAS procedure, and during operation, the processor further performs operations comprising:

starting the timer with the value responsive to receiving the response message,

wherein the re-attempting or resuming of the NAS procedure is performed after the timer expires.
The apparatus of Claim 9, wherein the second indication indicates a number of satellites in sequence that the apparatus needs to wait before re-attempting or resuming the NAS procedure, and during operation, the processor further performs operations comprising:

determining a second satellite with the number of satellites next to the first satellite,

wherein the re-attempting or resuming of the NAS procedure is performed in an event that a second satellite is available at a location of the apparatus.
The apparatus of Claim 14, wherein, during operation, the processor further performs operations comprising:

receiving, via the transceiver, broadcast system information from the network node, wherein the broadcast system information comprises satellite assistance information comprising ephemeris data or satellite in-coverage or out-of-coverage information, and

wherein the second satellite is determined based on the satellite assistance information.
The apparatus of Claim 9, wherein the second indication comprises a satellite identifier (ID) for indicating in which satellite the apparatus is allowed to re-attempt or resume the NAS procedure, and the re-attempting or resuming of the NAS procedure is performed in an event that a second satellite associated with the satellite ID is available at a location of the apparatus.
A method, comprising:

receiving, by a processor of a network node, a request message for initiating a non-access stratum (NAS) procedure from an apparatus, wherein the network node comprises a first satellite; and

transmitting, by the processor, a response message corresponding to the NAS procedure to the apparatus, wherein the response message comprises at least one of a first indication that the NAS procedure is not completed and a second indication for assisting the apparatus on subsequent re-attempts or resumptions of the NAS procedure.
The method of Claim 17, wherein the first satellite is operating in a store-and-forward operation mode.
The method of Claim 17, wherein the first indication is a reject cause and the second indication comprises at least one of the following:

a value of a timer for indicating when the apparatus is allowed to re-attempt or resume the NAS procedure;

a number of satellites in sequence that the apparatus needs to wait before re-attempting or resuming the NAS procedure; and

a satellite identifier (ID) for indicating in which satellite the apparatus is allowed to re-attempt or resume the NAS procedure.
The method of Claim 17, further comprising:

transmitting, by the processor, broadcast system information to the apparatus, wherein the broadcast system information comprises satellite assistance information comprising ephemeris data or satellite in-coverage or out-of-coverage information.