Apparatus and method for allocating dedicated preamble for random access in wireless communication system

Abstract

The present disclosure is for allocating a dedicated preamble for random access in a wireless communication system. A method performed by a terminal may comprise the steps of: transmitting, by the terminal, a message related to random access for a service; receiving, by the terminal, information related to the dedicated preamble for random access; and when disconnection of the service occurs, performing, by the terminal, random access for connection recovery of the service by using the dedicated preamble.

Description

Dedicated preamble allocation device and method for random access in a wireless communication system

[0001] The following description relates to a wireless communication system, and more particularly, to a device and method for allocating a dedicated preamble for random access in a wireless communication system.

[0002] Wireless access systems are widely deployed to provide various types of communication services, such as voice and data. Typically, wireless access systems are multiple access systems that support communications with multiple users by sharing available system resources (e.g., bandwidth, transmission power). Examples of multiple access systems include code division multiple access (CDMA), frequency division multiple access (FDMA), time division multiple access (TDMA), orthogonal frequency division multiple access (OFDMA), and single-carrier frequency division multiple access (SC-FDMA).

[0003] In particular, as numerous communication devices demand greater communication capacity, enhanced mobile broadband (eMBB) communication technologies are being proposed, improving upon existing radio access technology (RAT). Furthermore, massive machine type communications (mMTC), which connects multiple devices and objects to provide diverse services anytime and anywhere, as well as communication systems that consider reliability and latency-sensitive services / user equipment (UE), are being proposed. Various technological configurations are being proposed for these solutions.

[0004] The present disclosure relates to a device and method for allocating a dedicated preamble for random access in a wireless communication system.

[0005] The present disclosure relates to a device and method for quickly restoring a connection for a service sensitive to communication interruption time in a wireless communication system.

[0006] The present disclosure relates to a device and method for allocating a random access dedicated preamble for a service sensitive to communication interruption time in a wireless communication system.

[0007] The present disclosure relates to a device and method for determining the number of random access dedicated preambles to be allocated for a service sensitive to communication interruption time in a wireless communication system.

[0008] The present disclosure relates to a device and method for limiting the validity time of a random access-only preamble in a wireless communication system.

[0009] The present disclosure relates to a device and method for adjusting the validity time of a random access-only preamble in a wireless communication system.

[0010] The present disclosure relates to a device and method for determining the number of random access dedicated preambles to be used for a handover request in a wireless communication system.

[0011] The present disclosure relates to a device and method for determining the number of random access dedicated preambles to be allocated for a service sensitive to communication interruption time based on the number of random access dedicated preambles to be used for a handover request in a wireless communication system.

[0012] The present disclosure relates to a device and method for determining the number of random access dedicated preambles to be allocated for a service sensitive to communication downtime based on information related to the number of communication downtime-sensitive applications running on a terminal in a wireless communication system.

[0013] The present disclosure relates to a device and method for restoring a connection using a random access-only preamble when a connection of a service having a time limitation related to connection restoration is disconnected in a wireless communication system.

[0014] The technical objectives to be achieved in the present disclosure are not limited to those mentioned above, and other technical tasks not mentioned can be considered by a person having ordinary skill in the technical field to which the technical configuration of the present disclosure is applied from the embodiments of the present disclosure described below.

[0015] As an example of the present disclosure, the method may include a step of a terminal transmitting a message related to random access for a service, a step of the terminal receiving information related to a dedicated preamble for random access, and a step of the terminal performing random access for connection recovery of the service using the dedicated preamble when a connection disconnection of the service occurs.

[0016] As an example of the present disclosure, the method may include the steps of a base station receiving a message related to random access for a service from a terminal, the step of the base station determining at least one dedicated preamble for random access related to the service, and the step of transmitting information related to the determined at least one dedicated preamble to the terminal.

[0017] As an example of the present disclosure, the method may include a step in which a server receives a message related to random access for a service of a terminal, a step in which the server determines a time length value of a timer related to a dedicated preamble of the random access, and a step in which the server transmits the time length value of the timer to a serving base station of the terminal.

[0018] As an example of the present disclosure, a device includes a transceiver and a processor connected to the transceiver, wherein the processor is configured to transmit a message related to random access for a service, receive information related to a dedicated preamble for random access, and perform random access for connection recovery of the service using the dedicated preamble when a connection disconnection of the service occurs.

[0019] As an example of the present disclosure, a device includes a transceiver and a processor connected to the transceiver, wherein the processor is configured to receive a message related to random access for a service from a terminal, determine at least one dedicated preamble for random access related to the service, and control transmission of information related to the determined at least one dedicated preamble to the terminal.

[0020] As an example of the present disclosure, a device includes a transceiver and a processor connected to the transceiver, wherein the processor controls a server to receive a message related to random access for a service of a terminal, the server to determine a time length value of a timer related to a dedicated preamble of the random access, and the server to transmit the time length value of the timer to a serving base station of the terminal.

[0021] As an example of the present disclosure, a communication device includes at least one processor, and at least one memory storing instructions that direct operations when executed by the at least one processor, wherein the operations may include a step of a terminal transmitting a message related to random access for a service, a step of the terminal receiving information related to a dedicated preamble for random access, and a step of the terminal performing random access for connection recovery of the service using the dedicated preamble when a connection disconnection of the service occurs.

[0022] As an example of the present disclosure, a non-transitory computer-readable medium storing at least one instruction, wherein the at least one instruction is executable by a processor to control transmitting a message related to random access for a service, receiving information related to a dedicated preamble for random access, and performing random access for connection recovery of the service using the dedicated preamble when a connection disconnection of the service occurs.

[0023] The above-described aspects of the present disclosure are only some of the preferred embodiments of the present disclosure, and various embodiments reflecting the technical features of the present disclosure can be derived and understood by a person having ordinary skill in the art based on the detailed description of the present disclosure to be described below.

[0024] The following effects may be achieved by embodiments based on the present disclosure.

[0025] The present disclosure can quickly restore a connection for a service sensitive to communication interruption time by using a dedicated preamble in a wireless communication system.

[0026] The effects that can be obtained from the embodiments of the present disclosure are not limited to the effects mentioned above, and other effects that are not mentioned can be clearly derived and understood by those skilled in the art to which the technical configuration of the present disclosure is applied, from the description of the embodiments of the present disclosure below. In other words, unintended effects that result from implementing the configuration described in the present disclosure can also be derived by those skilled in the art from the embodiments of the present disclosure.

[0027] The accompanying drawings are intended to aid in understanding the present disclosure and, together with detailed descriptions, may provide embodiments of the present disclosure. However, the technical features of the present disclosure are not limited to specific drawings, and the features disclosed in each drawing may be combined with each other to form new embodiments. Reference numerals in each drawing may indicate structural elements.

[0028] Figure 1 illustrates an example of a communication system applicable to the present disclosure.

[0029] FIG. 2 illustrates an example of a user equipment (UE) applicable to the present disclosure.

[0030] FIG. 3 illustrates an example of functional separation of a next generation radio access network (NG-RAN) and a 5th generation core (5GC) applicable to the present disclosure.

[0031] FIG. 4 illustrates an example of a general architecture of a 5G (5th generation) system applicable to the present disclosure.

[0032] Figure 5 illustrates an example of inter-robot behavior when a network of service robots with peripheral intelligence collaborate on a joint project.

[0033] FIG. 6 is an example of a dedicated preamble allocation procedure according to an embodiment of the present disclosure.

[0034] FIG. 7 illustrates an example of a procedure for requesting dedicated preamble allocation according to an embodiment of the present disclosure.

[0035] FIG. 8 illustrates an example of a procedure for restoring a connection according to an embodiment of the present disclosure.

[0036] FIG. 9 illustrates an example of a procedure for allocating a dedicated preamble according to an embodiment of the present disclosure.

[0037] FIG. 10 illustrates an example of determining the time length of a timer according to an embodiment of the present disclosure.

[0038] The following embodiments combine components and features of the present disclosure in a predetermined form. Each component or feature may be considered optional unless explicitly stated otherwise. Each component or feature may be implemented without being combined with other components or features. Furthermore, some components and / or features may be combined to form embodiments of the present disclosure. The order of operations described in the embodiments of the present disclosure may be changed. Some components or features of one embodiment may be included in another embodiment or may be replaced with corresponding components or features of another embodiment.

[0039] In the description of the drawings, procedures or steps that may obscure the gist of the present disclosure are not described, and procedures or steps that can be understood by a person skilled in the art are also not described.

[0040] Throughout the specification, when a part is said to "comprising" or "including" a component, this does not mean that other components may be included, but rather that other components may be excluded, unless otherwise specifically stated. In addition, terms such as "...part," "...unit," and "module" described in the specification mean a unit that processes at least one function or operation, which may be implemented by hardware, software, or a combination of hardware and software. In addition, the words "a" or "an," "one," "the," and similar related words may be used in the context of describing the present disclosure (especially in the context of the claims below) to include both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context.

[0041] Embodiments of the present disclosure described herein focus on the data transmission and reception relationship between a base station and a mobile station. Here, the base station is understood as a terminal node of a network that directly communicates with the mobile station. Certain operations described herein as being performed by the base station may, in some cases, be performed by an upper node of the base station.

[0042] That is, in a network consisting of multiple network nodes including a base station, various operations performed for communication with a mobile station may be performed by the base station or other network nodes other than the base station. In this case, the term 'base station' may be replaced by terms such as fixed station, Node B, eNB (eNode B), gNB (gNode B), ng-eNB, advanced base station (ABS), or access point.

[0043] Additionally, in embodiments of the present disclosure, the term terminal may be replaced with terms such as user equipment (UE), mobile station (MS), subscriber station (SS), mobile subscriber station (MSS), mobile terminal, or advanced mobile station (AMS).

[0044] Additionally, a transmitter refers to a fixed and / or mobile node that provides data or voice services, and a receiver refers to a fixed and / or mobile node that receives data or voice services. Therefore, for uplink, a mobile station can be the transmitter, and a base station can be the receiver. Similarly, for downlink, a mobile station can be the receiver, and a base station can be the transmitter.

[0045] Embodiments of the present disclosure are wireless access systems such as IEEE 802.xx system, 3rd Generation Partnership Project (3GPP) system, 3GPP Long Term Evolution (LTE) system, 3GPP 5G (5 th generation) NR (New Radio) system and 3GPP2 system, and in particular, embodiments of the present disclosure may be supported by 3GPP TS (technical specification) 38.211, 3GPP TS 38.212, 3GPP TS 38.213, 3GPP TS 38.321 and 3GPP TS 38.331 documents.

[0046] Furthermore, the embodiments of the present disclosure can be applied to other wireless access systems and are not limited to the aforementioned systems. For example, they can also be applied to systems implemented after the 3GPP 5G NR system, and are not limited to a specific system.

[0047] That is, obvious steps or parts not described in the embodiments of the present disclosure can be explained by referring to the above documents. In addition, all terms disclosed in this document can be explained by the above standard documents.

[0048] Hereinafter, preferred embodiments according to the present disclosure will be described in detail with reference to the accompanying drawings. The detailed description set forth below, together with the accompanying drawings, is intended to illustrate exemplary embodiments of the present disclosure and is not intended to represent the only embodiments in which the technical configurations of the present disclosure may be implemented.

[0049] Additionally, specific terms used in the embodiments of the present disclosure are provided to aid in understanding the present disclosure, and the use of such specific terms may be changed to other forms without departing from the technical spirit of the present disclosure.

[0050] The following technology can be applied to various wireless access systems such as CDMA (code division multiple access), FDMA (frequency division multiple access), TDMA (time division multiple access), OFDMA (orthogonal frequency division multiple access), and SC-FDMA (single carrier frequency division multiple access).

[0051]

[0052] For clarity, the following description is based on a 3GPP communication system (e.g., LTE, NR, etc.), but the technical spirit of the present invention is not limited thereto. LTE may refer to technology after 3GPP TS 36.xxx Release 8. Specifically, LTE technology after 3GPP TS 36.xxx Release 10 may be referred to as LTE-A, and LTE technology after 3GPP TS 36.xxx Release 13 may be referred to as LTE-A pro. 3GPP NR may refer to technology after TS 38.xxx Release 15. 3GPP 6G may refer to technology after TS Release 17 and / or Release 18. "xxx" refers to a standard document detail number. LTE / NR / 6G may be collectively referred to as a 3GPP system.

[0053] For background information, terms, abbreviations, etc. used in this disclosure, reference may be made to standard documents published prior to the present invention. For example, reference may be made to the 36.xxx and 38.xxx standard documents.

[0054] For terms, abbreviations, and other background technologies that may be used in this document, please refer to the following standard documents published prior to this document. In particular, terms, abbreviations, and other background technologies related to LTE / EPS (Evolved Packet System) can refer to the 36.xxx series, 23.xxx series, and 24.xxx series, and terms, abbreviations, and other background technologies related to NR (new radio) / 5GS (5G system) can refer to the 38.xxx series, 23.xxx series, and 24.xxx series.

[0055] Hereinafter, this specification is described based on the terms defined above.

[0056] The three key requirement areas for 5G include (1) Enhanced Mobile Broadband (eMBB), (2) Massive Machine Type Communication (mMTC), and (3) Ultra-reliable and Low Latency Communications (URLLC).

[0057] Some use cases may require optimization across multiple domains, while others may focus on just one Key Performance Indicator (KPI). 5G supports these diverse use cases in a flexible and reliable manner.

[0058]

[0059] Communication system applicable to the present disclosure

[0060] Although not limited thereto, the various descriptions, functions, procedures, proposals, methods and / or operational flowcharts of the present disclosure disclosed in this document may be applied to various fields requiring wireless communication / connectivity (e.g., 5G) between devices.

[0061] Hereinafter, more specific examples will be provided with reference to the drawings. In the drawings / descriptions below, the same drawing reference numerals may represent identical or corresponding hardware blocks, software blocks, or functional blocks, unless otherwise described.

[0062] Figure 1 illustrates an example of a communication system applied to the present disclosure.

[0063] Referring to FIG. 1, a communication system (100) applied to the present disclosure includes a wireless device, a base station, and a network. Here, the wireless device refers to a device that performs communication using a wireless access technology (e.g., 5G NR, LTE) and may be referred to as a communication / wireless / 5G device. Although not limited thereto, the wireless device may include a robot (100a), a vehicle (100b-1, 100b-2), an XR (extended reality) device (100c), a hand-held device (100d), a home appliance (100e), an IoT (Internet of Things) device (100f), and an AI (artificial intelligence) device / server (100g). For example, the vehicle may include a vehicle equipped with a wireless communication function, an autonomous vehicle, a vehicle capable of performing vehicle-to-vehicle communication, etc. Here, the vehicles (100b-1, 100b-2) may include unmanned aerial vehicles (UAVs) (e.g., drones). The XR devices (100c) include augmented reality (AR) / virtual reality (VR) / mixed reality (MR) devices, and may be implemented in the form of head-mounted devices (HMDs), head-up displays (HUDs) installed in vehicles, televisions, smartphones, computers, wearable devices, home appliances, digital signage, vehicles, robots, etc. The portable devices (100d) may include smartphones, smart pads, wearable devices (e.g., smartwatches, smart glasses), computers (e.g., laptops, etc.), etc. The home appliances (100e) may include TVs, refrigerators, washing machines, etc. The IoT devices (100f) may include sensors, smart meters, etc. For example, the base station (120) and the network (130) may also be implemented as wireless devices, and a specific wireless device (120a) may act as a base station / network node to other wireless devices.

[0064] Wireless devices (100a to 100f) can be connected to a network (130) via a base station (120). AI technology can be applied to the wireless devices (100a to 100f), and the wireless devices (100a to 100f) can be connected to an AI server (100g) via a network (130). The network (130) can be configured using a 3G network, a 4G (e.g., LTE) network, a 5G (e.g., NR) network, etc. The wireless devices (100a to 100f) can communicate with each other via the base station (120) / network (130), but can also communicate directly (e.g., sidelink communication) without going through the base station (120) / network (130). For example, vehicles (100b-1, 100b-2) can communicate directly (e.g., V2V (vehicle to vehicle) / V2X (vehicle to everything) communication). In addition, IoT devices (100f) (e.g., sensors) can communicate directly with other IoT devices (e.g., sensors) or other wireless devices (100a to 100f).

[0065] Wireless communication / connection (150a, 150b, 150c) can be established between wireless devices (100a to 100f) / base stations (120), and base stations (120) / base stations (120). Here, the wireless communication / connection can be established through various wireless access technologies (e.g., 5G NR) such as uplink / downlink communication (150a), sidelink communication (150b) (or D2D communication), and base station-to-base station communication (150c) (e.g., relay, IAB (integrated access backhaul)). Through the wireless communication / connection (150a, 150b, 150c), the wireless device and base station / wireless device, and base stations and base stations can transmit / receive wireless signals to / from each other. For example, the wireless communication / connection (150a, 150b, 150c) can transmit / receive signals through various physical channels. To this end, based on various proposals of the present disclosure, at least some of various configuration information setting processes for transmitting / receiving wireless signals, various signal processing processes (e.g., channel encoding / decoding, modulation / demodulation, resource mapping / demapping, etc.), resource allocation processes, etc. may be performed.

[0066]

[0067] Figure 2 illustrates an example of a UE applicable to the present disclosure.

[0068] Referring to FIG. 2, the UE (200) may include a processor (102), memory (104), a transceiver (106), one or more antennas (108), a power management module (141), a battery (142), a display (143), a keypad (144), a SIM (Subscriber Identification Module) card (145), a speaker (146), and a microphone (147).

[0069] The processor (102) may be configured to implement the descriptions, functions, procedures, proposals, methods, and / or flowcharts disclosed herein. The processor (102) may be configured to control one or more other components of the UE (200) to implement the descriptions, functions, procedures, proposals, methods, and / or flowcharts disclosed herein. A layer of a radio interface protocol may be implemented in the processor (102). The processor (102) may include an ASIC, other chipset, logic circuit, and / or data processing device. The processor (102) may be an application processor. The processor (102) may include at least one of a DSP, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), and a modem (modulator and demodulator).

[0070] The memory (104) is operatively coupled to the processor (102) and can store various information for operating the processor (102). The memory (104) may include ROM, RAM, flash memory, a memory card, a storage medium, and / or other storage devices. When the implementation is implemented in software, the techniques described herein may be implemented using modules (e.g., procedures, functions, etc.) that perform the descriptions, functions, procedures, suggestions, methods, and / or operational flowcharts disclosed herein. The modules may be stored in the memory (14) and executed by the processor (102). The memory (104) may be implemented within the processor (102) or external to the processor (102), in which case it may be communicatively coupled to the processor (102) via various methods known in the art.

[0071] A transceiver (106) is operably coupled to the processor (102) and is capable of transmitting and / or receiving radio signals. The transceiver (106) may include a transmitter and a receiver. The transceiver (106) may include baseband circuitry for processing radio frequency signals. The transceiver (106) may control one or more antennas (108) to transmit and / or receive radio signals.

[0072] The power management module (141) can manage the power of the processor (102) and / or the transceiver (106). The battery (142) can supply power to the power management module (141).

[0073] The display (143) can output the results processed by the processor (102). The keypad (144) can receive input to be used by the processor (102). The keypad (144) can be displayed on the display (143).

[0074] A SIM card (145) is an integrated circuit that securely stores an International Mobile Subscriber Identity (IMSI) and associated keys, and can be used to identify and authenticate subscribers in mobile devices such as mobile phones and computers. Additionally, contact information can be stored on many SIM cards.

[0075] The speaker (146) can output sound-related results processed by the processor (102). The microphone (147) can receive sound-related input to be used by the processor (102).

[0076] In implementations of this specification, a UE may operate as a transmitter in the uplink and as a receiver in the downlink. In implementations of this specification, a base station may operate as a receiver in the uplink and as a transmitter in the downlink. In this specification, a base station may be referred to as a Node B (Node B), an eNode B (eNB), or a gNB, and may not be limited to a specific form.

[0077] In addition, for example, the UE may be implemented in various forms depending on the use case / service. The UE may be composed of various components, devices / parts, and / or modules. For example, each UE may include a communication device, a control device, a memory device, and additional components. The communication device may include a communication circuit and a transceiver. For example, the communication circuit may include one or more processors and / or one or more memories. For example, the transceiver may include one or more transceivers and / or one or more antennas. The control device is electrically connected to the communication device, the memory device, and the additional components, and may control the overall operation of each UE. For example, the control device may control the electrical / mechanical operation of each UE based on a program / code / command / information stored in the memory device. The control device may transmit information stored in the memory device to an external device (e.g., another communication device) via the communication device via a wireless / wired interface, or may store information received from an external device (e.g., another communication device) via the communication device via a wireless / wired interface in the memory device.

[0078] Additional components may be configured in various ways depending on the type of UE. For example, the additional components may include at least one of a power unit / battery, an input / output (I / O) device (e.g., an audio I / O port, a video I / O port), a driving device, and a computing device. In addition, the UE is not limited thereto, and may be implemented in the form of a robot (100a in FIG. 1), a vehicle (100b-1 and 100b-2 in FIG. 1), an XR device (100c in FIG. 1), a portable device (100d in FIG. 1), a home appliance (100e in FIG. 1), an IoT device (100f in FIG. 1), a digital broadcasting terminal, a hologram device, a public safety device, an MTC device, a medical device, a fintech device (or a financial device), a security device, a climate / environmental device, an AI server / device (100g in FIG. 1), a base station (120 in FIG. 1), or a network node. UE can be used in mobile or fixed locations depending on the use case / service.

[0079] The various components, devices / parts, and / or modules of the UE may all be connected to each other via a wired interface, or at least some of them may be connected wirelessly via a communication device. In addition, each component, device / part, and / or module of the UE may further include one or more elements. For example, the control device may be configured by a set of one or more processors. For example, the control device may be configured by a set of a communication control processor, an application processor (AP), an electronic control unit (ECU), a graphics processing unit, and a memory control processor. As another example, the memory device may be configured by a random access memory (RAM), a dynamic random access memory (DRAM), a read-only memory (ROM), a flash memory, a volatile memory, a non-volatile memory, and / or a combination thereof.

[0080]

[0081] 5G system architecture applicable to the present disclosure

[0082] The 5G system is an advanced technology from the 4th generation LTE mobile communication technology. It supports new radio access technology (RAT: Radio Access Technology), extended LTE (eLTE) as an extended technology of LTE (Long Term Evolution), and non-3GPP (e.g., WLAN) access through the evolution or clean-state structure of the existing mobile communication network structure.

[0083] 5G systems are defined as service-based, and the interactions between network functions (NFs) within the architecture for 5G systems can be expressed in two ways as follows.

[0084] - Reference point representation: Represents the interaction between NF services within NFs described by a point-to-point reference point (e.g., N11) between two NFs (e.g., AMF and SMF).

[0085] Service-based representation: Network functions (e.g., AMF) within the control plane (CP) allow other authorized network functions to access their services. This representation also includes point-to-point reference points, if necessary.

[0086] 5GC (5G Core) can include various components, some of which include access and mobility management function (AMF), session management function (SMF), policy control function (PCF), user plane function (UPF), application function (AF), unified data management (UDM), and non-3GPP interworking function (N3IWF).

[0087] The UE connects to the data network via the UPF via the next-generation radio access network (NG-RAN) that includes the gNB. The UE can receive data services via untrusted non-3GPP access points, such as wireless local area networks (WLANs). To connect non-3GPP access points to the core network, an N3IWF may be deployed.

[0088] The N3IWF manages interworking between non-3GPP access and 5G systems. When a UE is connected to a non-3GPP access (e.g., WiFi, also known as IEEE 802.11), it can connect to a 5G system via the N3IWF. The N3IWF performs control signaling with the AMF and connects to the UPF via the N3 interface for data transmission.

[0089] AMF can manage access and mobility in 5G systems. It can also manage non-access stratum (NAS) security. It can also handle mobility in idle states.

[0090] The UPF functions as a gateway for transmitting and receiving user data. A UPF node can perform all or part of the user plane functions of a 4G mobile communications S-GW (serving gateway) and P-GW (packet data network gateway).

[0091] The UPF acts as a boundary point between the next generation RAN (NG-RAN) and the core network, and is an element that maintains the data path between the gNB and the SMF. In addition, the UPF acts as a mobility anchor point when the UE moves across the area served by the gNB. The UPF can perform the function of handling PDUs. For mobility within the NG-RAN (e.g., NG-RAN defined after 3GPP Release-15), the UPF can route packets. In addition, the UPF can also act as an anchor point for mobility with other 3GPP networks (e.g., RAN defined before 3GPP Release-15), such as UTRAN (UMTS (universal mobile telecommunications system) terrestrial radio access network), E-UTRAN (evolved-UTRAN), or GERAN (GSM (global system for mobile communication) / EDGE (enhanced data rates for global evolution) radio access network). A UPF may correspond to the termination point of a data interface toward a data network.

[0092] The PCF is a node that controls the operator's policies. The AF is a server that provides various services to UEs. The UDM is a server that manages subscriber information, similar to the HSS (home subscriber server) of 4G mobile communications. The UDM (460) stores and manages subscriber information in a unified data repository (UDR).

[0093] The SMF can perform the function of assigning an IP (Internet protocol) address to the UE. In addition, the SMF can control the PDU (protocol data unit) session.

[0094] For convenience of explanation below, the drawing symbols for AMF, SMF, PCF, UPF, AF, UDM, N3IWF, gNB, or UE may be omitted, and operation may be performed by referring to the matters described in standard documents published prior to this document.

[0095] Figure 3 illustrates an example of functional separation of NG-RAN and 5GC (5th generation core) applicable to the present disclosure.

[0096] Referring to Figure 3, the UE connects to a data network (DN) via a next-generation RAN. The control plane function (CPF) node performs all or part of the functions of the mobility management entity (MME) of 4G mobile communications, and all or part of the control plane functions of the serving gateway (S-GW) and the PDN gateway (P-GW). The CPF node includes the AMF and the SMF.

[0097] The UPF node functions as a gateway through which user data is transmitted and received.

[0098] The authentication server function (AUSF) authenticates and manages UEs. The Network Slice Selection Function (NSSF) is a node for network slicing, as described below.

[0099] The network exposure function (NEF) provides a mechanism to securely expose the services and functions of the 5G core.

[0100] The reference points shown in Fig. 3 are as follows. N1 represents a reference point between the UE and the AMF. N2 represents a reference point between the (R)AN and the AMF. N3 represents a reference point between the (R)AN and the UPF. N4 represents a reference point between the SMF and the UPF. N5 represents a reference point between the PCF and the AF. N6 represents a reference point between the UPF and the DN. N7 represents a reference point between the SMF and the PCF. N8 represents a reference point between the UDM and the AMF. N9 represents a reference point between the UPFs. N10 represents a reference point between the UDM and the SMF. N11 represents a reference point between the AMF and the SMF. N12 represents a reference point between the AMF and the AUSF. N13 represents a reference point between the UDM and the AUSF. N14 represents a reference point between the AMFs. N15 represents a reference point between a PCF and an AMF in a non-roaming scenario, and a reference point between an AMF and a PCF of a visited network in a roaming scenario. N16 represents a reference point between SMFs. N22 represents a reference point between an AMF and an NSSF. N30 represents a reference point between a PCF and an NEF. N33 may represent a reference point between an AF and an NEF, and the entities and interfaces described above may be configured with reference to those described in standard documents published before this document. N58 represents a reference point between an AMF and an NSSAAF. N59 represents a reference point between a UDM and an NSSAAF. N80 represents a reference point between an AMF and an NSACF. N81 represents a reference point between an SMF and an NSACF.

[0101] The radio interface protocol is based on the 3GPP radio access network standard. Horizontally, the radio interface protocol consists of the physical layer, data link layer, and network layer. Vertically, it is divided into the user plane for data information transmission and the control plane for control signaling.

[0102] Protocol layers can be divided into L1 (layer-1), L2 (layer-2), and L3 (layer-3) based on the three lower layers of the open systems interconnection (OSI) standard model, which is widely known in communication systems.

[0103] Below, the present disclosure describes each layer of the wireless protocol. Figure 4 illustrates an example of a general architecture of a 5G (5th generation) system applicable to the present disclosure.

[0104] Referring to FIG. 4, the AS (access stratum) layer may include a physical (PHY) layer, a medium access control layer, a radio link control (RLC) layer, a packet data convergence protocol (PDCP) layer, and a radio resource control (RRC) layer, and operations based on each layer may be performed by referring to matters described in standard documents published prior to this document.

[0105]

[0106] Specific embodiments of the present disclosure

[0107] The present disclosure relates to a device and method for allocating a dedicated preamble for random access in a wireless communication system. Specifically, the present disclosure relates to a device and method for allocating a dedicated preamble for random access for a time-sensitive service in a wireless communication system. The term "time-sensitive" in the present disclosure refers to applications being sensitive to communication interruption times or communication disconnection times. Accordingly, time-sensitive services include services that are sensitive to communication interruption times or the length of communication interruption times, and time-sensitive applications include applications that are sensitive to communication interruption times or the length of communication interruption times.

[0108]

[0109] First, some terms used in this disclosure are explained.

[0110] An automated robot is a robot that performs a given task, and operates like an automaton without adapting to environmental changes and / or following a scripted plan. A fully autonomous robot is a robot that performs a given task, adapting to operating and environmental conditions, and performing the task without human intervention. An orientation measure is basically a measurement attributed to an object that relates to information about the position the object points to with respect to a reference object in an orientation coordinate system. The object can be a physical object within SUMO, and the measurement can be a measurement within SUMO.

[0111] An orientation region is defined as a region or interval orientation relative to a reference object (an object within SUMO). For example, the "South" interval on a compass constitutes an orientation region in the compass's one-dimensional circular coordinate system. Position regions and orientation regions can be referred to similarly. For example, it is valid to say that a robot is at position North and is facing North. The former relates to the position region, i.e., the North region of a particular country, while the latter relates to the orientation region, i.e., the directional interval centered around North on the compass. An orientation value is a value in a coordinate system that defines a particular direction, and an orientation value in one coordinate system can be mapped to another. An orientation value can be used in expressions such as "The robot is positioned at an angle of 54° to the reference object."

[0112] A remote-controlled robot is a robot that performs a given task, and a human operator can continuously control the robot simply by directly observing it from a distance. A remote-controlled robot does not have initiative and relies on continuous or near-continuous input from a human operator. The robot actuating part is a device (a device within SUMO) that enables the robot to move and act within its environment. The robot communicating part is a device (a device within SUMO) that acts as a tool within the robot, robot communication process, or human-robot communication process by enabling the robot to exchange information with other robots or humans.

[0113] A robot group is a group of robots organized to achieve at least one common goal (a group within SUMO). The robot processing part includes a processing unit that enables the robot to process information. The robot sensing part includes a measurement unit (a measurement unit within SUMO) that enables the robot to collect information about the environment. A robot is a broadly defined agent device (agents and devices within SUMO) that acts in the physical world to perform one or more tasks. In some cases, the robot's actions may be dependent on the actions of other agents (agents within SUMO), such as software agents (bots) or humans. A robot is composed of appropriate mechanical and electronic components. Robots can form social groups that interact to achieve a common goal. A robot or group of robots can form a robot system with a specialized environment designed to facilitate its tasks. A semi-autonomous robot is a robot that performs some tasks without human intervention and some tasks with human intervention.

[0114] Operators plan and perform tasks that require varying levels of human interaction. A tandem subnetwork is a group of robots connected serially as UEs for a traffic session. Note that, according to this definition, a tandem subnetwork can have rings. For example, if robot A connects to robot C via intermediate robot B for a traffic session, these three robots can be said to form a tandem subnetwork. If robot A has two different paths to robot C for a single traffic session—one via robot B1 and one via robot B2—these four robots can be said to form a tandem subnetwork.

[0115] A teleoperated robot is a robot that performs a given task. Its actuators are controlled by a human operator using sensory feedback from outside the robot, or it can be continuously assigned progressive goals. Even if the command is complex or time-consuming, a teleoperated robot can complete the last command after the operator has stopped transmitting it.

[0116]

[0117] Section 5.1 of 3GPP TR 22.916 states:

[0118] --------------------------------------------------------------------

[0119] 5.1 Online cooperative high-resolution 3D map building

[0120] This use case considers a low-energy (or energy-efficient) collaborative scenario where multiple robot groups collaborate to build a 3D map for use in unstructured environments, such as corporate building cleaning, large-scale building disinfection preparation, or agricultural automation. Collaborating with multiple robots to collect measurement data can save energy, produce better-quality results, or both [5-7].

[0121] Note 1: Some aspects related to 'agricultural automation' may also be studied in scenarios combining ground and aerial mobility.

[0122] Note 2: In this use case, the meaning of 'map' is not necessarily limited to geographical shapes, but may also include still objects that are useful or essential for robots operating in irregular or unstructured environments.

[0123] A group of service robots with multi-dimensional surrounding sensing, computing (standalone and / or via a computing fabric), learning and model building federation, and 3GPP subscription-based communication capabilities collaborate on a common project.

[0124] Availability of communication services with the edge (or cloud) is divided into three categories: unavailable, temporarily unavailable, and available (for a certain period of time; the term "available" is interpreted positively, although it does not imply "permanent availability").

[0125] Note 3: This use case focuses mostly on ProSe-based operations (also known as “ProSe-enabled”) with partial or intermittent connectivity to NG-RAN (or edge servers via NG-RAN).

[0126] Edge (server) helps alleviate the computational burden on service robots, if available to one or more of these service robots (whether within the scope of 3GPP or not), and may create demand for access to service-specific network slices or other forms of network resources with specific performance requirements.

[0127] The operator of the robot application starts to operate a group of service robots called UEs.

[0128] These service robots discover each other and share their capabilities.

[0129] Note 4: For each service robot (UE), the capabilities include specific characteristics such as the type of RAT supported (e.g. NR, E-UTRA or non-3GPP access technology) and information that is not within the scope of the communication layer, such as battery level.

[0130] All or some of these service robots form a working group (with one or more leader robots) and initiate communication.

[0131] Member robots transmit measurement data to the leader robot, allowing the leader robot to take the next step and build a 3D map.

[0132] Note 5: The role of the leader robot(s) includes coordinating the operation of a work group of service robots, such as acting as a synchronization master for other robots (synchronization devices) within the work clock domain.

[0133] These service robots scan environmental parameters, including 3GPP service availability, and collaboratively decide which operational scenario to select (i.e., Uu-based or ProSe-based, also known as ProSe-assisted).

[0134] Each service robot within a work group walks cooperatively with each other, forming a clustered structure (i.e., the distance between any pair is not unnecessarily large, which degrades the performance of the map construction results).

[0135] Each service robot is exposed to uneven surfaces along its trajectory (e.g., signal angle measurements are not static, which may result in unexpected loss of measurement accuracy levels).

[0136] At a given point on the job site, based on the accuracy level of the 3D map and the decision of the leader robot(s), the application layer of the leader robot requests that the clock synchronization target value be adjusted within the clock synchronization budget.

[0137] During the move, one of the member robots, called Robot A, may experience a problem, causing its movement speed to slow down unexpectedly.

[0138] Member robot A anticipates this problem in advance: it reports this information to the leader robot as a follow-up action and timestamps the measurement data containing this outlier situation.

[0139] It is up to member robot A to decide whether to transmit measurement data with outlier indications to the leader robot.

[0140] It is up to the leader robot to decide whether to use the received data with outlier indications from member robot A for 3D map construction.

[0141] Later, member robot A moves away from the cluster and temporarily loses connection with the relay UE robot (or gNB in ​​a Uu-based scenario). Member robot A immediately resumes the connection.

[0142] ---------------------------------------------------------------------

[0143] Figure 5 illustrates an example of inter-robot behavior when a network of service robots with peripheral intelligence collaborate on a joint project.

[0144] ----------------------------------------------------------------------

[0145] A working group of service robots can build 3D maps with just the required level of accuracy, eliminating the need to expend computing and communication resources to build overly accurate 3D maps of areas.

[0146] Additionally, for critical areas, the accuracy level can be adjusted.

[0147] Prediction-based indications can be used to avoid potential noise factors that could affect 3D map quality.

[0148] A robot that is momentarily disconnected can very quickly reconnect and transmit time-critical information to the other member(s).

[0149] 5.1.2 Related Existing Service Requirements

[0150] Clock synchronization: 3GPP TS 22.104 [2]

[0151] - Section 5.6.1 Clock Synchronization Service Level Requirements

[0152] - Section 5.6.2 Clock Synchronization Service Performance Requirements

[0153] - Section 7.2.3.2 Clock Synchronization Requirements

[0154] Timing Resilience: 3GPP TS 22.261 [3]

[0155] - Section 6.36.2 General requirements for ensuring timing resilience

[0156] - Section 6.36.3 Monitoring and Reporting

[0157] - Section 6.36.4 Exposure

[0158] Multipath Relay: 3GPP TS 22.261 [3]

[0159] - Section 6.9.2.1 Support for traffic flow of remote UEs through other indirect network connection paths

[0160] Positioning: 3GPP TS 22.261 [3]

[0161] - Section 7.3.2 High-precision positioning performance requirements (see section 5.7.1 of 3GPP TS 22.104 for future factory scenarios)

[0162] Service Continuity: 3GPP TS 22.263 [4]

[0163] - Section 5.5 Service Continuity

[0164] 5.1.3 Challenges and Potential Gaps

[0165] Further research and confirmation of the following applicable aspects are recommended and, where appropriate, may be considered in conjunction with other ongoing or recently completed studies.

[0166] [CPG-5.1.3-001] The 5G system shall be able to provide a means to ensure very high accuracy clock synchronization (i.e., synchronization between service robots within a collaborative group and synchronization between multiple sources associated with each service robot) to support a group of service robots to collaboratively build a 3D map. The accuracy levels required at the application layer are expected to be as follows:

[0167] Note 1: Clock synchronization accuracy is provided in 5G systems to support applications requiring time-sensitive communication. Higher accuracy levels are expected depending on the requirements of the robotics application layer. In scenarios involving a group of robots interconnected via multi-hops, the current clock synchronization accuracy levels (e.g., Collaborative Transport - Fragile Workpieces; (A.2.2.5), Table 7.2.3.2-1, 3GPP TS 22.104) may not be sufficient. It is also discussed that a smaller clock synchronization budget may be required to support collaborative robot (cobot) scenarios with additional network elements within the robots behind the UE.

[0168] [CPG-5.1.3-002] It is expected that the 5G system will be able to ensure the integrity and validity of clock synchronization for a specified length of time when a group of service robots operates ProSe-based outside the coverage area provided by the NG-RAN.

[0169] Note 2: The length of time varies depending on the type of project and the application of the service robot.

[0170] [CPG-5.1.3-003] If the integrity and validity of clock synchronization cannot be guaranteed for a specified length of time, the 5G system is expected to notify the application.

[0171] [CPG-5.1.3-004] It is expected that 5G systems will be able to provide a means for UE(s) to adjust the level of accuracy of clock synchronization.

[0172] [CPG-5.1.3-005] It is expected that 5G systems will be able to provide a means to share information related to the accuracy level and integrity of clock synchronization with the cloud (Uu-based scenario) or a leader robot (ProSe-based scenario).

[0173] [CPG-5.1.3-006] It is expected that 5G systems will be able to provide a means to resume a connection when an ongoing connection is interrupted (e.g., due to a radio link failure between a robot and a communicating party) within a very short timeframe required by the application layer.

[0174] Note 3: The current time interval for safe reconnection should be less than 1 second. Critical robotic applications may require much shorter times: less than 100 ms for critical cases, and less than 10 ms for critical cases.

[0175] Note 4: This requirement does not apply to scenarios where the service robot experiences more severe levels of disruption, such as 3GPP registration status changes.

[0176] [CPG-5.1.3-007] It is expected that the 5G system will be able to provide a means for member robots to propagate necessary information required by the application layer to one or more destinations within a very short time required by the application layer, when a communication failure or measurement failure is predicted.

[0177] Note 5: The required time interval varies depending on the application (e.g., less than 100 milliseconds for a moderate level of interruption, less than 10 milliseconds for a severe level of interruption). The above CPG applies to both RRC Connected mode and RRC Inactive mode. The above CPG does not apply to RRC Idle mode.

[0178] [CPG-5.1.3-008] Based on a request from an application (e.g., an application of a leader robot in a robot group or an application in a cloud server), the 5G system is expected to be able to determine specific areas where the system can adjust the clock synchronization accuracy level and provide a way to expose network capabilities (e.g., the ability to monitor “clock synchronization accuracy level”) and monitoring results (e.g., the measured accuracy level in the area of ​​interest) to the application.

[0179] Note 6: Possible scenarios regarding the groups of robots referenced include groups of “automated robots”, groups of “fully autonomous robots”, groups of “teleoperated robots”, and groups comprising any appropriate combination of these types of robots.

[0180] Note 7: The example scenario for a robotics application in Appendix B can be used to adjust the level of clock synchronization accuracy provided by 5G. The level of accuracy provided by a 5G system may vary depending on availability, and the level required by the application layer may vary depending on the time and environment in which the task is performed.

[0181] Note 8: In 3GPP TS 22.104 [2], Table 5.6.2-1 presents various scenarios that require different clock synchronization accuracy levels. The above CPG (i.e., [CPG-5.1.3-008]) is intended for specific applications or tasks of a robot (or group of robots) where the clock synchronization accuracy level needs to be adjusted due to changes in the application or changes in the capabilities of the 5G system.

[0182] ----------------------------------------------------------------------

[0183] As mentioned above, in the event of a connection loss due to a wireless link failure or other reason between the robot and the communication partner, a means to reestablish the connection within the very short timeframe required by the application layer must be provided. For example, to ensure a pleasant user experience for voice call users experiencing call disconnection or interruption, the safe reconnection time interval should be less than 150 ms (0.15 seconds). Applications with critical roles may require even shorter safe reconnection times.

[0184]

[0185] To ensure timely recovery from interrupted connections (e.g., connection failures) in timely, time-sensitive robotic applications can perform contention-free random access based on dedicated preambles. That is, the robot can utilize a dedicated preamble for random access, thereby avoiding the delay associated with contention resolution for random access attempts.

[0186] Dedicated preambles can be used not only for handover requests, but also to quickly restore lost communication links in time-sensitive robotic applications. In this case, to maintain the same probability of encountering a situation where no dedicated preambles are available at the time of a handover request, a larger number of preambles should be allocated to the dedicated preamble set.

[0187] In some existing technologies, 5G systems, 6G systems, and / or base stations utilize timers for allocation as described above to prevent a robot from occupying a dedicated preamble for an excessively long time without using the dedicated preamble if the connection for a time-sensitive robot application is not interrupted.

[0188] 5G systems, 6G systems, and / or base stations must determine how many preambles to allocate as dedicated preambles and for how long. For example, the base station must determine the number of preambles to be allocated as dedicated preambles and the length of the timer.

[0189] If too many random access opportunities are reserved for a robotic application, opportunities for other applications may be wasted. If too few random access opportunities are reserved for a robotic application, the performance of the robotic application, which is sensitive to communication interruptions, may degrade. Therefore, determining the number of dedicated preambles and the timer duration for a robotic application is crucial.

[0190] Accordingly, the present disclosure proposes a device and method for determining the number of dedicated preambles and the timer time length for a robotic application in a wireless communication system.

[0191]

[0192] FIG. 6 is an example of a dedicated preamble allocation procedure according to an embodiment of the present disclosure. Here, the terminal (UE) (610) may include a robot.

[0193] Referring to FIG. 6, in step S601, the terminal (610) begins executing at least one application. The at least one application may include a time-sensitive application. A time-sensitive application is an application sensitive to communication interruption time, and may include an application that must very quickly restore a disconnected connection when communication is interrupted.

[0194] In step S603, the terminal (610) transmits a fast recovery RA (random access) request message to the server (630) via the base station (gNB) (620-1). The fast recovery RA request message is a message requesting allocation of a random access-only preamble for a time-sensitive application and may be referred to as fast_recovery_ra_request. The fast recovery RA request message may include repetition-related indication information indicating whether the request message is the first request message or a repeated request message. For example, the repetition-related indication information may indicate whether the message is the first time transmitted after the execution of a time-sensitive application or whether the message is transmitted again after the execution of the application due to the expiration of a related timer (timer, T1). If the fast recovery RA request message is a repeated request message rather than the first request message, the fast recovery RA request message may include at least one of a previously used T1 value and interruption experience information. The previously used T1 value may include the length of time T1 was used before transmitting the repeat request message. For example, the previously used T1 value may indicate the length of validity time for a dedicated preamble previously assigned to the terminal (610). The interruption experience information may include historical information indicating whether communication has been interrupted for the application in question. The RA request message for rapid recovery may be a message requesting a dedicated preamble for a newly created communication service based on the execution of a time-sensitive application.

[0195] In step S605, the server (630) determines the value of the timer T1 based on the information received from the terminal. The server (630) may determine or adjust the length of time to be used for the timeout of the dedicated preamble to be allocated to the terminal (610) based on at least some information included in the fast recovery RA request message. For example, the server (630) may determine whether the corresponding message is the first request message or a repeated message based on the indication information included in the fast recovery RA request message. If the corresponding message is the first message, the server (630) may determine the value of the timer T1. At this time, the value of the timer T1 may be determined to a value within a range preset for T1. For example, the value of the timer T1 may be determined to a minimum value (T1_min), a maximum value (T1_max), or a specific value between the minimum and maximum values ​​preset by the operator. On the other hand, if the message is a repetitive message, the server (630) can check the value of previously used T1 included in the RA request message for fast recovery and adjust the value of the confirmed T1. If the RA request message for fast recovery includes more interruption experience information, the server (630) can adjust the value of the confirmed T1 by further considering the interruption experience information. For example, the server (630) can increase or decrease the value of the confirmed T1 by using a predetermined step-size value or factor.

[0196] In step S607, the server (630) transmits a fast recovery allow request (fast_recovery_allow_request) message to the base station (620-1). The fast recovery allow request message may be a message allowing the terminal (610) to use a dedicated preamble. It may include the value of T1 determined or adjusted in step S605, i.e., the time length of T1.

[0197] In step S609, the base station (620-1) transmits a message requesting information and / or statistics about the handover to at least one neighboring base station (620-2). For example, the base station (620-1) may request information and / or statistics about the handover from at least one neighboring base station (620-2) to obtain information necessary to determine the number of dedicated preambles to be allocated for a CFRA-based handover request. The information about the handover may include the number of handover requests currently generated from at least one neighboring base station (620-2). The statistics may include various information (e.g., average, variance, etc.) obtained by collecting, organizing, analyzing, and / or interpreting handover requests currently generated from at least one neighboring base station (620-2). For example, the statistics may include the number of handover requests generated on average during a time interval of a specified length, i.e., per unit time, from at least one neighboring base station (620-2). Information and / or statistical information regarding handovers is provided for illustrative purposes only and is not limited thereto.

[0198] In step S611, at least one neighboring base station (620-2) transmits a response message to the base station (620-1) containing information about the handover and / or statistical information. For example, the response message may include information related to the number of incoming handover requests (HO requests) received per unit time by the at least one neighboring base station (620-2). This may vary depending on the ongoing session at the cell site of the at least one neighboring base station (620-2).

[0199] In step S613, the base station (620-1) determines the first number of dedicated preambles for the handover request. The base station (620-1) may determine the first number of dedicated preambles to minimize handover failures using a specific mathematical method. For example, the base station (620-1) may determine the first number of dedicated preambles for the CFRA-based handover request based on the following mathematical equations 1 to 3.

[0200] The following [Mathematical Formula 1] is the total penalty function.

[0201]

[0202] In [Equation 1], is the number of handover requests In case of is a penalty function for , is a probability mass function (PMF) for parameter k, which defines the number of handover requests.

[0203] When there are multiple classes of time-sensitive applications, the total penalty function can be generalized to integrate multiple classes as in [Equation 2].

[0204]

[0205] In [Equation 2], , and these functions are defined in the same way as for a single class.

[0206]

[0207]

[0208] In [Equation 3], depends on resource availability, time constraints (e.g. latency, jitter), etc.

[0209] In step S615, the base station (620-1) transmits a message requesting information on the number of time-sensitive applications and / or statistical information to the server (630). In other words, the base station (620-1) may transmit a message requesting information on the number of time-sensitive applications currently running on terminals serviced by the base station (620-1) and / or statistical information related thereto to the server (630). This is because the base station (620-1) cannot know information on the service level.

[0210] In step S617, the server (630) transmits a response message including the information requested from the base station (620-1) to the base station (620-1). For example, the response message may include information on the number of time-sensitive applications currently running on a terminal served by the base station (620-1) and / or statistical information related thereto. The statistical information may include various information (e.g., average, variance, etc.) obtained by collecting, organizing, analyzing, and / or interpreting information on the number of times time-sensitive applications have been run and / or the time of execution on a terminal served by the base station (620-1) to date. For example, the statistical information may include information on the number of time-sensitive applications run on average on the terminal (610) during a time interval of a specified length, i.e., per unit time. This is merely an example to help understanding and is not limited thereto.

[0211] In step S619, the base station (620-1) determines a second number of dedicated preambles for time-sensitive applications based on information and / or statistical information obtained from the server (630). For example, the base station (620-1) may determine the second number of dedicated preambles for time-sensitive applications based on at least one of the first number of dedicated preambles for a CFRA-based handover request, or the information and / or statistical information regarding the number of applications obtained in step S617.

[0212] In step S621, the base station (620-1) may determine the initial length of the timer T1 (i.e., T1_0, which is the initial value or start value of the timer T1). According to one embodiment, the initial value of the timer T1 may be the value determined by the server (630) in step S605. According to one embodiment, step S621 may be performed for the corresponding terminal (610) if the RA request message for fast recovery is the first request. On the other hand, if the RA request message for fast recovery is a repeated request rather than the first request, step S621 may be omitted.

[0213] At step S623, the base station (620-1) may allocate dedicated resources to the terminal (610), and at step S625, may transmit a message to the server (630) indicating that the request has been accepted. At step S619, the base station (620-1) may allocate dedicated preambles to the terminal (610) based on the second number of dedicated preambles.

[0214] According to one embodiment, the base station (620-1) can check whether the dedicated preambles corresponding to the second number of dedicated preambles are available. If the dedicated preambles corresponding to the second number of dedicated preambles are not available, the base station (621-1) may not perform steps S623 and S625, but may transmit a message indicating that the request has been rejected to at least one of the terminal (610) and the server (630). On the other hand, if the dedicated preambles corresponding to the second number of dedicated preambles are available, the base station (621-1) may perform steps S623 and S625.

[0215] According to one embodiment, the base station (620-1) may check the number of available dedicated preambles within a designated subset to determine whether dedicated preambles corresponding to the second number of dedicated preambles are available. For example, the base station (620-1) may check the number of dedicated preambles within the designated subset that are not allocated or occupied by at least one other terminal, and compare the identified number of dedicated preambles with the second number of dedicated preambles. If the identified number of dedicated preambles is greater than or equal to the second number of dedicated preambles, the base station (620-1) may determine that the dedicated preambles corresponding to the second number of dedicated preambles are available, and may allocate the identified dedicated preambles within the designated subset to the terminal (610). Here, the designated subset may include an RA subset designated for a time delay-sensitive robotic application. Alternatively, the designated subset may include a designated RA subset for handover requests and delay-sensitive robotic applications. For example, the designated subset may include at least one of a subset including RA preambles only for delay-sensitive robotic applications, or a subset including RA preambles for handover requests and delay-sensitive robotic applications.

[0216] In the embodiment described with reference to FIG. 6, the determined and / or adjusted time length value of T1 may be notified to the terminal (610) in step S621 or step S623. When the time length value of T1 is received, the terminal (610) may set and start operating T1 according to the received time length value. For example, T1 may be started when the terminal (610) is allocated a second number of dedicated preambles for time-sensitive applications.

[0217] According to one embodiment, when the timer T1 expires in the terminal (610), the procedure described with reference to FIG. 6 may be re-performed. In other words, steps S601 to S625 may be re-performed when the timer T1 expires in the terminal (610). This is because when the timer T1 expires, the use of the second number of dedicated preambles is restricted. That is, the terminal may transmit an RA request message for rapid recovery to be reallocated dedicated preambles for time-sensitive applications when the timer T1 expires.

[0218] In one embodiment, the terminal (610) may retransmit the RA request message for rapid recovery before T1 expires, for example, at a time earlier than a designated time interval before T1 expires. The designated time interval may be set by considering the average time taken from the time the terminal (610) transmits the RA request message for rapid recovery until the terminal (610) is allocated or granted a dedicated preamble.

[0219] In the embodiment described with reference to FIG. 6, the base station (620-1) and the server (630) may be implemented as components included in a single device. According to one embodiment, the server (630) may be located in the same location within the base station (620-1) or may be located in a geographically separate location from the base station (620-1).

[0220] In the embodiment described with reference to FIG. 6, the initial value of T1, i.e., the initial time length, may be set to either a minimum value (T1_min) or a maximum value (T1_max) set by the base station or the mobile network operator.

[0221] When the initial value of T1 is set to a minimum value, the value of T1 may be gradually increased. For example, the base station may gradually increase the value of T1 using a specified step size value or a specified factor whenever an RA request message for rapid recovery is received from the terminal. For example, the base station may gradually increase the value of T1 by performing an addition operation or a multiplication operation on a previously determined value of T1 and the specified step size value or the specified factor. In this case, the base station may control so that the value of T1 is not set or determined to a value greater than the maximum value.

[0222] When the initial value of T1 is set to the maximum value, the value of T1 may be gradually decreased. For example, the base station may gradually decrease the value of T1 using a specified step size value or a specified factor whenever an RA request message for rapid recovery is received from the terminal. For example, the base station may gradually decrease the value of T1 by performing a subtraction operation, an inverse multiplication operation, or a division operation on a previously determined value of T1 and the specified step size value or the specified factor. In this case, the base station may control so that the value of T1 is not set or determined to a value less than a minimum value.

[0223] According to an embodiment described with reference to FIG. 6, a base station determines a first number of dedicated preambles for a handover request based on information about a handover and / or statistical information obtained from an adjacent base station, and determines a second number of dedicated preambles for time-sensitive applications based on the first number and information about the number of time-sensitive applications and / or statistical information related thereto. According to various embodiments, at least one other information may be further utilized to determine the second number of dedicated preambles for time-sensitive applications. For example, the base station may determine the second number of dedicated preambles for time-sensitive applications by further considering the number of RA request messages for fast recovery received per unit time.

[0224]

[0225] FIG. 7 illustrates an example of a procedure for requesting dedicated preamble allocation according to one embodiment of the present disclosure. A terminal (UE) (710) may include a robot UE application layer (712) and a robot UE communication layer (714). According to one embodiment, at least some of the operations in FIG. 7 may be understood as detailed operations of step S601 of FIG. 6.

[0226] Referring to FIG. 7, in step S701, the robot UE application layer (712) of the terminal (710) executes a robot application (e.g., robotic application #X). The robot application may be executed by a given task or by a request from a user or operator.

[0227] In step S703, the robot UE application layer (712) of the terminal (710) determines whether the executed robot application is a time-sensitive application. The robot UE application layer (712) of the terminal (710) can determine whether the executed robot application is a time-sensitive application based on the identification information of the executed robot application or the type of service provided by the executed robot application. For example, the terminal (710) can obtain a list including identification information of time-sensitive applications in advance. In this case, the terminal (710) can determine whether the executed robot application is a time-sensitive application by comparing the identification information of the executed robot application with the list. Alternatively, the terminal (710) can determine whether the executed robot application is a time-sensitive application based on whether the service provided by the executed robot application is a time-sensitive service. If the application is a time-sensitive application, the robot UE application layer (712) of the terminal (710) can notify the robot UE communication layer (714) that the execution of the time-sensitive application has begun.

[0228] In step S705, the robot UE communication layer (714) of the terminal (710) adds an indicator to the RA request for fast recovery (fast_recovery_ra_request) message. For example, the robot UE communication layer (714) of the terminal (710) may generate the RA request for fast recovery message including an indicator indicating that the executed robot application is a time-sensitive application.

[0229] In step S707, the robot UE communication layer (714) of the terminal (710) may transmit an RA request message for rapid recovery to the server (730). The RA request message for rapid recovery may include at least one of an indicator indicating that the executed robot application is a time-sensitive application, instruction information related to repetition, a previously used T1 value, and interruption experience information.

[0230]

[0231] Figure 8 illustrates an example of a procedure for restoring a connection according to an embodiment of the present disclosure. Figure 8 illustrates a method performed by a terminal. The terminal may include a robot capable of executing at least one robot application.

[0232] Referring to FIG. 8, in step S801, a terminal transmits a message related to random access. The message related to random access may include a message requesting a random access-only preamble. The terminal may detect the execution of a time-sensitive application and transmit a message requesting a random access-only preamble for the time-sensitive application (e.g., an RA request message for rapid recovery) to the base station. The time-sensitive application may include an application that provides a service with a time constraint related to connection recovery. The message requesting a random access-only preamble may be a message requesting a random access-only preamble to be used for rapid recovery in the event of a connection disconnection for the time-sensitive application. The message requesting a random access-only preamble may include at least one of instruction information related to the repetition of the corresponding request message, the value of a previously used timer, or interruption experience information.

[0233] According to one embodiment, a terminal may transmit capability information of the terminal to a base station and receive configuration information from the base station prior to transmitting a message related to random access. The capability information of the terminal may include supportable services or capability information related to communication. For example, the capability information may include information indicating whether support for a service with a time limit related to connection recovery is possible. The configuration information may include configuration information for a service with a time limit related to connection recovery. For example, the configuration information may include information regarding a time limit for connection recovery of the service.

[0234] In step S803, the terminal receives information related to a dedicated preamble. The terminal receives information related to a dedicated preamble for random access from the base station. For example, the terminal may receive information related to at least one dedicated preamble to be used for random access for connection recovery in the event of a connection disconnection for a time-sensitive application, i.e., a connection related to the corresponding service, from the base station. The information related to at least one dedicated preamble may include at least one dedicated preamble index information. According to one embodiment, the terminal may receive from the base station a time length value of a timer T1 used to limit the allocation time or validity time of the dedicated preamble. The time length value of the timer T1 may be received together with the dedicated preamble-related information or may be received separately from the dedicated preamble-related information. When the time length value of the timer T1 is received, the terminal may set a timer according to the received time length value and start the timer based on the reception time of the dedicated preamble-related information.

[0235] In step S805, the terminal performs a random access based on a dedicated preamble. If a connection related to a time-sensitive application is disconnected, the terminal may initiate a contention-free random access procedure based on one of at least one dedicated preamble allocated from the base station. For example, the terminal may transmit the dedicated preamble allocated to the terminal to the base station to restore the connection within a limited time for service connection restoration. According to one embodiment, the terminal may verify the validity of the pre-allocated dedicated preamble based on whether timer T1 has expired. If timer T1 has not expired, the terminal may determine that the pre-allocated dedicated preamble is valid and may perform random access based on the pre-allocated dedicated preamble. If timer T1 has expired, the terminal may determine that the pre-allocated dedicated preamble is invalid and may retransmit a message requesting a dedicated preamble.

[0236] According to one embodiment, the terminal may further perform at least one operation of the terminal (610, 710) described in FIG. 6 and / or FIG. 7.

[0237]

[0238] FIG. 9 illustrates an example of a procedure for allocating a dedicated preamble according to an embodiment of the present disclosure. FIG. 9 illustrates a method performed by a base station.

[0239] Referring to FIG. 9, in step S901, a base station receives a message related to random access. The message related to random access may include a message requesting a random access-only preamble for a time-sensitive application (e.g., an RA request message for rapid recovery). The message requesting a random access-only preamble may be a message requesting a random access-only preamble to be used for rapid recovery in the event of a connection interruption for a time-sensitive application. The base station may receive a message requesting a random access-only preamble for a time-sensitive application from a terminal. The message requesting a random access-only preamble may include at least one of instruction information related to repetition of the corresponding request message, a value of a previously used timer, or interruption experience information.

[0240] According to one embodiment, the base station may receive terminal capability information from the terminal before receiving a message related to random access and transmit configuration information to the terminal. The terminal capability information may include supportable services or capability information related to communication. For example, the capability information may include information indicating whether a service with a time limit related to connection recovery is supported. The configuration information may include configuration information for a service with a time limit related to connection recovery. For example, the configuration information may include information regarding a time limit for connection recovery of the service.

[0241] In step S903, the base station determines a dedicated preamble. The base station may determine the number of dedicated preambles for random access related to the service of the terminal. Specifically, the base station may determine a first number of dedicated preambles for random access to be used for a handover request, and may determine a second number of dedicated preambles for random access to be used for connection recovery of the service of the terminal based on the determined first number. The base station may obtain at least one of information related to the number of time-sensitive applications running on the terminal served by the base station, or statistical information related thereto, and may determine the second number of dedicated preambles for random access to be used for connection recovery of the service of the terminal based further on the obtained at least one piece of information. According to one embodiment, the base station may determine the second number of dedicated preambles as at least one dedicated preamble to be allocated to the terminal from among dedicated preambles available within a designated subset of a set of dedicated preambles. The designated subset may include at least one of a first subset for connection recovery of the service only, or a second subset for a handover request and connection recovery of the service. For example, dedicated preambles within the first subset may be used only for connection recovery of a service, and dedicated preambles within the second subset may be used for at least one of a handover request and connection recovery of a service. According to one embodiment, the base station may obtain information related to the number of handover requests from at least one neighboring base station, and determine a first number of dedicated preambles for random access to be used for the handover request based on the obtained information. The information related to the number of handover requests may include at least one of the number of handover request messages received by the at least one neighboring base station, or statistical information related thereto.

[0242] In step S905, the base station transmits dedicated preamble-related information. The base station transmits to the terminal information related to at least one dedicated preamble to be assigned to the terminal. The information related to at least one dedicated preamble may include at least one dedicated preamble index.

[0243] According to one embodiment, a base station may transmit to a terminal a time length value of a timer T1 for limiting an allocation time or an effective time of a dedicated preamble. The time length value of the timer T1 may be transmitted together with dedicated preamble-related information or may be transmitted separately from the dedicated preamble-related information. The time length of the timer T1 may be determined by at least one of the base station or the server. The time length of the timer T1 may be determined or adjusted based on indication information related to repetition included in a message requesting a random access dedicated preamble. For example, if the indication information related to repetition indicates a first request, the time length of the timer T1 may be set to an initial value (e.g., a minimum value of T1 or a maximum value of T1). If the indication information related to repetition indicates a repeated request, the time length of the timer T1 may be set to an adjusted value based on a time length of T1 previously used by the terminal.

[0244] According to one embodiment, the base station may further perform at least one operation of the base station (620-1) described in FIG. 6. According to one embodiment, when the base station is implemented as a component within a single device with a server, the base station may further perform at least one operation of the server (630, 730) described in FIG. 6 and / or FIG. 7.

[0245]

[0246] FIG. 10 illustrates an example of determining the time length of a timer according to an embodiment of the present disclosure. FIG. 10 illustrates a method performed by a server.

[0247] Referring to FIG. 10, in step S1001, a server receives a message related to random access. The message related to random access may include a message requesting a random access-only preamble. The message requesting a random access-only preamble may be a message requesting a random access-only preamble to be used for rapid recovery in the event of a connection interruption for a time-sensitive application. The server may receive a message requesting a random access-only preamble for a time-sensitive application from a terminal via a base station. The message requesting a random access-only preamble may include at least one of instruction information related to repetition of the request message, a value of a previously used timer, or interruption experience information.

[0248] In step S1003, the server determines the time length value of the timer associated with the dedicated preamble. The server may determine the time length value of the timer T1 to limit the validity time of the dedicated preamble to be allocated to the terminal. The time length of the timer T1 may be determined or adjusted based on the instruction information related to the repetition request included in the message requesting the random access dedicated preamble, i.e., the random access-related message. For example, if the instruction information related to repetition indicates the first request, the time length of the timer T1 may be set to an initial value (e.g., the minimum value of T1 or the maximum value of T1). If the instruction information related to repetition indicates a repeated request, the time length of the timer T1 may be set to an adjusted value based on the time length of T1 previously used by the terminal. According to one embodiment, if the instruction information related to repetition indicates the first request, the server may request the base station to set the timer T1 to an initial value.

[0249] In step S1005, the server transmits the time length value of the timer. The server may transmit a message containing the determined time length value to the terminal's serving base station. The transmitted message may include a message permitting the terminal to use a dedicated preamble to quickly restore the terminal's service.

[0250] According to one embodiment, the base station may further perform at least one operation of the server (630) described in FIG. 6.

[0251]

[0252] It is clear that the examples of the proposed methods described above can also be considered as a type of proposed methods, as they can be included as one of the implementation methods of the present disclosure. Furthermore, the proposed methods described above can be implemented independently, but they can also be implemented in the form of a combination (or merge) of some of the proposed methods. Information regarding the applicability of the proposed methods (or information regarding the rules of the proposed methods) can be defined by a rule such that the base station notifies the terminal of the application of the proposed methods through a predefined signal (e.g., a physical layer signal or a higher layer signal).

[0253] The present disclosure may be embodied in other specific forms without departing from the technical ideas and essential features described herein. Therefore, the above detailed description should not be construed as limiting in all respects but rather as illustrative. The scope of the present disclosure should be determined by a reasonable interpretation of the appended claims, and all modifications within the equivalent scope of the present disclosure are intended to be included within the scope of the present disclosure. Furthermore, claims that do not explicitly cite each other in the claims may be combined to form embodiments or incorporated into new claims through post-filing amendments.

[0254] Embodiments of the present disclosure can be applied to various wireless access systems. Examples of various wireless access systems include the 3rd Generation Partnership Project (3GPP) or 3GPP2 systems.

[0255] The embodiments of the present disclosure can be applied not only to the various wireless access systems described above, but also to all technical fields that utilize these various wireless access systems. Furthermore, the proposed method can also be applied to mmWave and THz communication systems utilizing ultra-high frequency bands.

[0256] Additionally, embodiments of the present disclosure can be applied to various applications such as autonomous vehicles and drones.

Claims

1. In the method, A step in which a terminal transmits a message related to random access for a service; A step in which the terminal receives information related to a dedicated preamble for random access; and A method comprising a step of the terminal performing random access for connection recovery of the service using the dedicated preamble when a connection disconnection of the service occurs.

2. In claim 1, A method in which the message related to the random access includes a message requesting a dedicated preamble for connection recovery of the service.

3. In claim 1, A method in which the message related to the random access includes at least one of instruction information related to repetition, the value of a timer previously used by the terminal, or information indicating a communication interruption history related to the service.

4. In claim 1, A method further comprising the step of receiving information related to the time length of a timer that limits the validity time of the dedicated preamble.

5. In claim 4, A method further comprising the step of retransmitting a message related to the random access when the timer set based on the time length expires.

6. In claim 1, A method further comprising the step of receiving configuration information for said service having a time limitation related to connection recovery.

7. In the method, A step in which a base station receives a message related to random access for a service from a terminal; a step in which the base station determines at least one dedicated preamble for random access related to the service; and A method comprising the step of transmitting information related to at least one of the determined dedicated preambles to the terminal.

8. In claim 7, The step of determining at least one dedicated preamble is: a step of determining the number of dedicated preambles for random access related to the above service; and A step of determining the above-determined number of dedicated preambles as at least one dedicated preamble for random access related to the service, A method in which the number of dedicated preambles for random access related to the above service is determined based on at least one of the number of handover requests per unit time of at least one neighboring base station, the number of messages related to random access received per unit time, or the number of designated applications running on a terminal served by the base station.

9. In claim 8, The step of determining the number of dedicated preambles for random access related to the above service is: A step of obtaining information related to the number of handover requests from at least one neighboring base station; Further comprising a step of determining the number of dedicated preambles for the handover request based on information related to the number of handover requests, The number of dedicated preambles for random access related to the above service is determined based on the number of dedicated preambles for the handover request, A method in which information related to the number of handover requests includes the number of handover requests per unit time of at least one adjacent base station.

10. In claim 8, The step of determining the number of dedicated preambles for random access related to the above service is: Further comprising a step of receiving information related to the number of designated applications running on a terminal serviced by the base station from the server, The number of dedicated preambles for random access related to the above service is determined based on information related to the number of designated applications running on the terminal, A method wherein the above-mentioned application comprises an application providing the service having a time limitation related to connection recovery.

11. In claim 7, A step of determining a time length value of a timer that limits the validity time of the above dedicated preamble; and A method further comprising the step of transmitting a time length value of the timer to the terminal.

12. In claim 11, A method in which the time length value of the above timer is determined based on instruction information related to a repeat request included in a message related to the random access.

13. In claim 11, A method in which the time length value of the above timer is determined based on an initial value or a time length value of the above timer previously used by the terminal.

14. In claim 7, A method further comprising the step of transmitting configuration information for said service having a time limitation related to connection recovery.

15. In the method, A step in which the server receives a message related to random access for a service of the terminal; The step of the server determining the time length value of the timer related to the dedicated preamble of the random access; and A method comprising a step in which the server transmits the time length value of the timer to the serving base station of the terminal.

16. In the device, Transmitter and receiver; and A processor connected to the above transmitter and receiver is included, The above processor, Send messages related to random access for services, Receive information related to a dedicated preamble for random access, A device that controls random access to restore connection of the service using the dedicated preamble when a connection disconnection of the above service occurs.

17. In the device, Transmitter and receiver; and A processor connected to the above transmitter and receiver is included, The above processor, Receive messages related to random access for services from the terminal, Determine at least one dedicated preamble for random access related to the above service, A device that controls the transmission of information related to at least one of the determined dedicated preambles to the terminal.

18. In the device, Transmitter and receiver; and A processor connected to the above transmitter and receiver is included, The above processor, The server receives a message related to random access for the terminal's service, The above server determines the time length value of the timer associated with the dedicated preamble of the random access, A device that controls the server to transmit the time length value of the timer to the serving base station of the terminal.

19. In communication devices, At least one processor; At least one memory storing instructions that direct operations when executed by at least one processor, The above actions are, A step in which a terminal transmits a message related to random access for a service; A step in which the terminal receives information related to a dedicated preamble for random access; A communication device including a step of the terminal performing random access for connection recovery of the service using the dedicated preamble when a connection disconnection of the service occurs.

20. In a non-transitory computer-readable medium storing at least one instruction, At least one instruction executable by the processor, Send messages related to random access for services, Receive information related to a dedicated preamble for random access, A computer-readable medium for controlling random access to restore connection of the service using the dedicated preamble when a connection disconnection of the service occurs.

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