WO2016018018A1

WO2016018018A1 - Method for performing prose discovery in wireless communication system and device therefor

Info

Publication number: WO2016018018A1
Application number: PCT/KR2015/007796
Authority: WO
Inventors: 김래영; 류진숙; 김현숙; 김재현; 김태훈
Original assignee: 엘지전자 주식회사
Priority date: 2014-07-27
Filing date: 2015-07-27
Publication date: 2016-02-04

Abstract

One embodiment of the present invention relates to a method by which a ProSe function performs a ProSe discovery in a wireless communication system, the method comprising the steps of: receiving, from a discoverer UE, a proximity request including a window and a range; and determining whether the discoverer UE will enter a proximity relation with a discoveree UE until the window expires, wherein, when the ProSe function determines that an improved ProSe discovery operation is to be performed, the ProSe function does not cancel a location reporting even if the window expires.

Description

Method for performing process discovery in wireless communication system and apparatus therefor

The following description relates to a wireless communication system, and more particularly, to a method and apparatus for performing process discovery.

Wireless communication systems are widely deployed to provide various kinds of communication services such as voice and data. In general, a wireless communication system is a multiple access system capable of supporting communication with multiple users by sharing available system resources (bandwidth, transmission power, etc.). Examples of multiple access systems include code division multiple access (CDMA) systems, frequency division multiple access (FDMA) systems, time division multiple access (TDMA) systems, orthogonal frequency division multiple access (OFDMA) systems, and single carrier frequency (SC-FDMA). division multiple access (MCD) systems and multi-carrier frequency division multiple access (MC-FDMA) systems.

In the present invention, it is a technical task to define a process discovery execution method and operations of related nodes.

The technical problems to be achieved in the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned above will be clearly understood by those skilled in the art from the following description. Could be.

A first technical aspect of the present invention is a method of performing ProSe discovery by a ProSe function in a wireless communication system, comprising: receiving a proximity request including a window and a range from a discoverer UE; Determining, by the discoverer UE, that a discovery enters a proximity relationship with the UE until the window expires, and when the ProSe function determines to perform an enhanced ProSe discovery operation, the ProSe function Discovery is a method that does not cancel location reporting even if the window expires.

In accordance with another aspect of the present invention, there is provided a ProSe function device for performing ProSe discovery in a wireless communication system, comprising: a transceiver module; And a processor, the processor receiving a proximity request from a discoverer UE, the proximity request comprising a window and a range, wherein the discoverer UE is in proximity with the discovery UE until the window expires. When the ProSe function determines to perform an enhanced ProSe discovery operation, the ProSe function is a ProSe function device that does not cancel location reporting even when the window expires.

The first to second technical aspects of the present invention may include one or more of the following.

If the proximity request includes time information (α) related to enhanced ProSe discovery, the ProSe function is determined from the window (β), range (γ) and time information (α) related to ProSe discovery (δ). Based on the determination, whether to perform the enhanced ProSe discovery operation may be determined.

The determined distance δ may be determined by {α / β} * γ.

When the distance between the discovery UE and the discovery UE is within the sum of the determined distance δ and range γ, it may be determined that the enhanced ProSe discovery operation is performed.

If the proximity request includes distance information (m) related to enhanced ProSe discovery, the ProSe function is determined from the window (β), range (γ) and distance information (m) related to the enhanced ProSe discovery (t). It may be decided to perform the enhanced ProSe discovery operation.

The determined time t may be determined by {m / γ} * β.

According to the present invention, an improved ProSe experience can be provided to a user who wants to find another UE / user.

The effects obtainable in the present invention are not limited to the above-mentioned effects, and other effects not mentioned above may be clearly understood by those skilled in the art from the following description. will be.

BRIEF DESCRIPTION OF THE DRAWINGS The drawings appended hereto are for the purpose of providing an understanding of the present invention and for illustrating various embodiments of the present invention and for describing the principles of the present invention together with the description of the specification.

1 is a diagram illustrating a schematic structure of an EPS (Evolved Packet System) including an Evolved Packet Core (EPC).

2 is an exemplary view showing the architecture of a general E-UTRAN and EPC.

3 is an exemplary view showing the structure of a radio interface protocol in a control plane.

4 is an exemplary view showing the structure of a radio interface protocol in a user plane.

5 is a flowchart illustrating a random access procedure.

6 is a diagram illustrating a connection process in a radio resource control (RRC) layer.

7 to 10 are views for explaining an embodiment of the present invention.

11 is a view for explaining ProSe (Proximity Service).

12 illustrates a procedure related to UE location reporting.

13 shows a procedure for proximity alert (Proximity Alert).

14 shows a procedure related to canceling a process request.

15 is a diagram illustrating a configuration of a node device according to an example of the present invention.

The following embodiments combine the components and features of the present invention in a predetermined form. Each component or feature may be considered to be optional unless otherwise stated. Each component or feature may be embodied in a form that is not combined with other components or features. In addition, some components and / or features may be combined to form an embodiment of the present invention. The order of the operations described in the embodiments of the present invention 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.

Specific terms used in the following description are provided to help the understanding of the present invention, and the use of such specific terms may be changed to other forms without departing from the technical spirit of the present invention.

In some instances, well-known structures and devices may be omitted or shown in block diagram form centering on the core functions of the structures and devices in order to avoid obscuring the concepts of the present invention. In addition, the same components will be described with the same reference numerals throughout the present specification.

Embodiments of the present invention may be supported by standard documents disclosed in relation to at least one of the Institute of Electrical and Electronics Engineers (IEEE) 802 series system, 3GPP system, 3GPP LTE and LTE-A system, and 3GPP2 system. That is, steps or parts which are not described to clearly reveal the technical spirit of the present invention among the embodiments of the present invention may be supported by the above documents. In addition, all terms disclosed in the present document can be described by the above standard document.

The following techniques can be used in various wireless communication systems. For clarity, the following description focuses on 3GPP LTE and 3GPP LTE-A systems, but the technical spirit of the present invention is not limited thereto.

Terms used in this document are defined as follows.

UMTS (Universal Mobile Telecommunications System): A third generation mobile communication technology based on Global System for Mobile Communication (GSM) developed by 3GPP.

Evolved Packet System (EPS): A network system composed of an Evolved Packet Core (EPC), which is a packet switched (PS) core network based on Internet Protocol (IP), and an access network such as LTE / UTRAN. UMTS is an evolutionary network.

NodeB: base station of GERAN / UTRAN. It is installed outdoors and its coverage is macro cell size.

eNodeB: base station of E-UTRAN. It is installed outdoors and its coverage is macro cell size.

UE (User Equipment): a user device. The UE may be referred to in terms of terminal, mobile equipment (ME), mobile station (MS), and the like. In addition, the UE may be a portable device such as a laptop, a mobile phone, a personal digital assistant (PDA), a smart phone, a multimedia device, or the like, or may be a non-portable device such as a personal computer (PC) or a vehicle-mounted device. In the context of MTC, the term UE or UE may refer to an MTC device.

Home NodeB (HNB): A base station of a UMTS network, which is installed indoors and has a coverage of a micro cell.

HeNB (Home eNodeB): A base station of an EPS network, which is installed indoors and its coverage is micro cell size.

Mobility Management Entity (MME): A network node of an EPS network that performs mobility management (MM) and session management (SM) functions.

Packet Data Network-Gateway (PDN-GW) / PGW: A network node of an EPS network that performs UE IP address assignment, packet screening and filtering, charging data collection, and the like.

Serving Gateway (SGW): A network node of an EPS network that performs mobility anchor, packet routing, idle mode packet buffering, and triggers the MME to page the UE.

Non-Access Stratum (NAS): Upper stratum of the control plane between the UE and the MME. A functional layer for exchanging signaling and traffic messages between a UE and a core network in an LTE / UMTS protocol stack, which supports session mobility and establishes and maintains an IP connection between the UE and the PDN GW. Supporting is the main function.

Packet Data Network (PDN): A network in which a server supporting a specific service (eg, a Multimedia Messaging Service (MMS) server, a Wireless Application Protocol (WAP) server, etc.) is located.

PDN connection: A logical connection between the UE and the PDN, represented by one IP address (one IPv4 address and / or one IPv6 prefix).

RAN (Radio Access Network): a unit including a NodeB, an eNodeB and a Radio Network Controller (RNC) controlling them in a 3GPP network. It exists between UEs and provides a connection to the core network.

Home Location Register (HLR) / Home Subscriber Server (HSS): A database containing subscriber information in the 3GPP network. The HSS may perform functions such as configuration storage, identity management, and user state storage.

Public Land Mobile Network (PLMN): A network composed for the purpose of providing mobile communication services to individuals. It may be configured separately for each operator.

Proximity Service (or ProSe Service or Proximity based Service): A service that enables discovery and direct communication between physically close devices or communication through a base station or through a third party device. In this case, user plane data is exchanged through a direct data path without passing through a 3GPP core network (eg, EPC).

ProSe communication: Means communication through a ProSe communication path between two or more ProSe capable terminals. Unless specifically stated otherwise, ProSe communication may mean one of ProSe E-UTRA communication, ProSe-assisted WLAN direct communication between two terminals, ProSe group communication, or ProSe broadcast communication.

-ProSe E-UTRA communication: ProSe communication using ProSe E-UTRA communication path

ProSe-assisted WLAN direct communication: ProSe communication using a direct communication path

ProSe communication path: As a communication path supporting ProSe communication, a ProSe E-UTRA communication path may be established between ProSe-enabled UEs or through a local eNB using E-UTRA. ProSe-assisted WLAN direct communication path can be established directly between ProSe-enabled UEs using WLAN.

EPC path (or infrastructure data path): user plane communication path through EPC

ProSe Discovery: A process of identifying / verifying a nearby ProSe-enabled terminal using E-UTRA

ProSe Group Communication: One-to-many ProSe communication using a common communication path between two or more ProSe-enabled terminals in close proximity.

ProSe UE-to-Network Relay: ProSe-enabled public safety terminal acting as a communication relay between ProSe-enabled network using E-UTRA and ProSe-enabled public safety terminal

ProSe UE-to-UE Relay: A ProSe-enabled public safety terminal operating as a ProSe communication relay between two or more ProSe-enabled public safety terminals.

ProSe-enabled Network: A network that supports ProSe Discovery, ProSe Communication, and / or ProSe-assisted WLAN direct communication. Hereinafter, the ProSe-enabled Network may be referred to simply as a network.

ProSe-enabled UE: a terminal supporting ProSe discovery, ProSe communication and / or ProSe-assisted WLAN direct communication. Hereinafter, the ProSe-enabled UE and the ProSe-enabled Public Safety UE may be called terminals.

Proximity: Satisfying proximity criteria defined in discovery and communication, respectively.

SULP Location Platform (SLP): An entity that manages Location Service Management and Position Determination. SLP includes a SPL (SUPL Location Center) function and a SPC (SUPL Positioning Center) function. For details, refer to the Open Mobile Alliance (OMA) standard document OMA AD SUPL: "Secure User Plane Location Architecture".

ISR (Idle mode Signaling Reduction): When a terminal frequently moves between E-UTRAN and UTRAN / GERAN, waste of network resources occurs by repeated location registration procedure. As a way to reduce this, when the terminal is in idle mode, two RATs (Radio Access Technology) already registered after the location registration with MME and SGSN (hereinafter referred to as mobility management node) via E-UTRAN and UTRAN / GERAN, respectively. This is a technology that does not register a separate location when moving between cells or performing cell reselection. Therefore, when DL (downlink) data arrives to the terminal, paging is simultaneously sent to the E-UTRAN and UTRAN / GERAN, thereby successfully finding the terminal and delivering the DL data. [See 3GPP TS 23.401 and 3GPP TS 23.060]

Evolved Packet Core (EPC)

EPC is a key element of System Architecture Evolution (SAE) to improve the performance of 3GPP technologies. SAE is a research project to determine network structure supporting mobility between various kinds of networks. SAE aims to provide an optimized packet-based system, for example, supporting various radio access technologies on an IP basis and providing enhanced data transfer capabilities.

Specifically, the EPC is a core network of an IP mobile communication system for a 3GPP LTE system and may support packet-based real-time and non-real-time services. In a conventional mobile communication system (i.e., a second generation or third generation mobile communication system), the core network is divided into two distinct sub-domains of circuit-switched (CS) for voice and packet-switched (PS) for data. The function has been implemented. However, in the 3GPP LTE system, an evolution of the third generation mobile communication system, the sub-domains of CS and PS have been unified into one IP domain. That is, in the 3GPP LTE system, the connection between the terminal and the terminal having the IP capability (capability), IP-based base station (for example, eNodeB (evolved Node B)), EPC, application domain (for example, IMS ( IP Multimedia Subsystem)). That is, EPC is an essential structure for implementing end-to-end IP service.

The EPC may include various components, and in FIG. 1, some of them correspond to a serving gateway (SGW), a packet data network gateway (PDN GW), a mobility management entity (MME), and a serving general packet (SGRS) Radio Service (Supporting Node) and Enhanced Packet Data Gateway (ePDG) are shown.

The SGW (or S-GW) acts as a boundary point between the radio access network (RAN) and the core network, and is an element that functions to maintain a data path between the eNodeB and the PDN GW. In addition, when the UE moves over the area served by the eNodeB, the SGW serves as a local mobility anchor point. That is, packets may be routed through the SGW for mobility in the E-UTRAN (Universal Mobile Telecommunications System (Evolved-UMTS) Terrestrial Radio Access Network defined in 3GPP Release-8 or later). SGW also provides mobility with other 3GPP networks (RANs defined before 3GPP Release-8, such as UTRAN or GERAN (Global System for Mobile Communication (GSM) / Enhanced Data rates for Global Evolution (EDGE) Radio Access Network). It can also function as an anchor point.

The PDN GW (or P-GW) corresponds to the termination point of the data interface towards the packet data network. The PDN GW may support policy enforcement features, packet filtering, charging support, and the like. In addition, mobility management between 3GPP networks and non-3GPP networks (for example, untrusted networks such as Interworking Wireless Local Area Networks (I-WLANs), code-division multiple access (CDMA) networks, or trusted networks such as WiMax) Can serve as an anchor point for.

Although the example of the network structure of FIG. 1 shows that the SGW and the PDN GW are configured as separate gateways, two gateways may be implemented according to a single gateway configuration option.

The MME is an element that performs signaling and control functions to support access to the network connection of the UE, allocation of network resources, tracking, paging, roaming and handover, and the like. The MME controls control plane functions related to subscriber and session management. The MME manages a number of eNodeBs and performs signaling for the selection of a conventional gateway for handover to other 2G / 3G networks. The MME also performs functions such as security procedures, terminal-to-network session handling, and idle terminal location management.

SGSN handles all packet data, such as user's mobility management and authentication to other 3GPP networks (eg GPRS networks).

The ePDG acts as a secure node for untrusted non-3GPP networks (eg, I-WLAN, WiFi hotspots, etc.).

As described with reference to FIG. 1, a terminal having IP capability is an IP service network provided by an operator (ie, an operator) via various elements in the EPC, based on 3GPP access as well as non-3GPP access. (Eg, IMS).

1 illustrates various reference points (eg, S1-U, S1-MME, etc.). In the 3GPP system, a conceptual link defining two functions existing in different functional entities of E-UTRAN and EPC is defined as a reference point. Table 1 below summarizes the reference points shown in FIG. 1. In addition to the examples of Table 1, there may be various reference points according to the network structure.

Table 1

Among the reference points shown in FIG. 1, S2a and S2b correspond to non-3GPP interfaces. S2a is a reference point that provides the user plane with associated control and mobility support between trusted non-3GPP access and PDN GW. S2b is a reference point that provides the user plane with relevant control and mobility support between the ePDG and PDN GW.

2 is an exemplary view showing the architecture of a general E-UTRAN and EPC.

As shown, an eNodeB can route to a gateway, schedule and send paging messages, schedule and send broadcaster channels (BCHs), and resources in uplink and downlink while an RRC (Radio Resource Control) connection is active. Can perform functions for dynamic allocation to the UE, configuration and provision for measurement of the eNodeB, radio bearer control, radio admission control, and connection mobility control. Within the EPC, paging can occur, LTE_IDLE state management, user plane can perform encryption, SAE bearer control, NAS signaling encryption and integrity protection.

3 is an exemplary diagram illustrating a structure of a radio interface protocol in a control plane between a terminal and a base station, and FIG. 4 is an exemplary diagram illustrating a structure of a radio interface protocol in a user plane between a terminal and a base station. .

The air interface protocol is based on the 3GPP radio access network standard. The air interface protocol is composed of a physical layer, a data link layer, and a network layer horizontally, and a user plane and control for data information transmission vertically. It is divided into a control plane for signal transmission.

The protocol layers are based on the lower three layers of the Open System Interconnection (OSI) reference model, which is widely known in communication systems, and includes L1 (first layer), L2 (second layer), and L3 (third layer). ) Can be separated.

Hereinafter, each layer of the radio protocol of the control plane shown in FIG. 3 and the radio protocol in the user plane shown in FIG. 4 will be described.

The physical layer, which is the first layer, provides an information transfer service using a physical channel. The physical layer is connected to a medium access control layer on the upper side through a transport channel, and data between the medium access control layer and the physical layer is transmitted through the transport channel. In addition, data is transferred between different physical layers, that is, between physical layers of a transmitting side and a receiving side through a physical channel.

The physical channel is composed of several subframes on the time axis and several sub-carriers on the frequency axis. Here, one subframe includes a plurality of symbols and a plurality of subcarriers on the time axis. One subframe consists of a plurality of resource blocks, and one resource block consists of a plurality of symbols and a plurality of subcarriers. The transmission time interval (TTI), which is a unit time for transmitting data, is 1 ms corresponding to one subframe.

According to 3GPP LTE, the physical channels existing in the physical layer of the transmitting side and the receiving side are physical downlink shared channel (PDSCH), physical uplink shared channel (PUSCH) and physical downlink control channel (PDCCH), which are control channels, It may be divided into a Physical Control Format Indicator Channel (PCFICH), a Physical Hybrid-ARQ Indicator Channel (PHICH), and a Physical Uplink Control Channel (PUCCH).

There are several layers in the second layer.

First, the medium access control (MAC) layer of the second layer serves to map various logical channels to various transport channels, and also logical channel multiplexing to map several logical channels to one transport channel. (Multiplexing). The MAC layer is connected to the upper layer RLC layer by a logical channel, and the logical channel includes a control channel for transmitting information of a control plane according to the type of information to be transmitted. It is divided into a traffic channel that transmits user plane information.

The Radio Link Control (RLC) layer of the second layer adjusts the data size so that the lower layer is suitable for transmitting data to the radio section by segmenting and concatenating data received from the upper layer. It plays a role.

The Packet Data Convergence Protocol (PDCP) layer of the second layer is an IP containing relatively large and unnecessary control information for efficient transmission in a wireless bandwidth where bandwidth is small when transmitting an IP packet such as IPv4 or IPv6. Performs Header Compression which reduces the packet header size. In addition, in the LTE system, the PDCP layer also performs a security function, which is composed of encryption (Ciphering) to prevent third-party data interception and integrity protection (Integrity protection) to prevent third-party data manipulation.

The radio resource control layer (hereinafter RRC) layer located at the top of the third layer is defined only in the control plane, and the configuration and resetting of radio bearers (abbreviated as RBs) are performed. It is responsible for the control of logical channels, transport channels and physical channels in relation to configuration and release. In this case, RB means a service provided by the second layer for data transmission between the terminal and the E-UTRAN.

When there is an RRC connection (RRC connection) between the RRC of the terminal and the RRC layer of the wireless network, the terminal is in an RRC connected state (Connected Mode), otherwise it is in an RRC idle mode (Idle Mode).

Hereinafter, the RRC state and the RRC connection method of the UE will be described. The RRC state refers to whether or not the RRC of the UE is in a logical connection with the RRC of the E-UTRAN. If the RRC state is connected, the RRC_CONNECTED state is called, and the RRC_IDLE state is not connected. Since the UE in the RRC_CONNECTED state has an RRC connection, the E-UTRAN can grasp the existence of the UE in units of cells, and thus can effectively control the UE. On the other hand, the UE in the RRC_IDLE state cannot identify the existence of the UE by the E-UTRAN, and the core network manages the unit in a larger tracking area (TA) unit than the cell. That is, the terminal in the RRC_IDLE state is only detected whether the terminal exists in a larger area than the cell, and the terminal must transition to the RRC_CONNECTED state in order to receive a normal mobile communication service such as voice or data. Each TA is identified by a tracking area identity (TAI). The terminal may configure a TAI through a tracking area code (TAC), which is information broadcast in a cell.

When the user first turns on the power of the terminal, the terminal first searches for an appropriate cell, then establishes an RRC connection in the cell, and registers the terminal's information in the core network. Thereafter, the terminal stays in the RRC_IDLE state. The terminal staying in the RRC_IDLE state (re) selects a cell as needed and looks at system information or paging information. This is called camping on the cell. When it is necessary to establish an RRC connection, the UE staying in the RRC_IDLE state makes an RRC connection with the RRC of the E-UTRAN through an RRC connection procedure and transitions to the RRC_CONNECTED state. There are several cases in which a UE in RRC_IDLE state needs to establish an RRC connection. For example, a user's call attempt, a data transmission attempt, etc. are required or a paging message is received from E-UTRAN. Reply message transmission, and the like.

A non-access stratum (NAS) layer located above the RRC layer performs functions such as session management and mobility management.

The following describes the NAS layer shown in FIG. 3 in detail.

ESM (evolved Session Management) belonging to the NAS layer performs functions such as default bearer management and dedicated bearer management, and is responsible for controlling the terminal to use the PS service from the network. The default bearer resource is characterized in that it is allocated from the network when it is connected to the network when it first accesses a specific Packet Data Network (PDN). At this time, the network allocates an IP address usable by the terminal so that the terminal can use the data service, and also allocates QoS of the default bearer. LTE supports two types of bearer having a guaranteed bit rate (GBR) QoS characteristic that guarantees a specific bandwidth for data transmission and reception, and a non-GBR bearer having a best effort QoS characteristic without guaranteeing bandwidth. In case of Default bearer, Non-GBR bearer is assigned. In the case of a dedicated bearer, a bearer having a QoS characteristic of GBR or non-GBR may be allocated.

The bearer allocated to the terminal in the network is called an evolved packet service (EPS) bearer, and when the EPS bearer is allocated, the network allocates one ID. This is called EPS Bearer ID. One EPS bearer has a QoS characteristic of a maximum bit rate (MBR) or / and a guaranteed bit rate (GBR).

5 is a flowchart illustrating a random access procedure in 3GPP LTE.

The random access procedure is used for the UE to get UL synchronization with the base station or to be allocated UL radio resources.

The UE receives a root index and a physical random access channel (PRACH) configuration index from the eNodeB. Each cell has 64 candidate random access preambles defined by a Zadoff-Chu (ZC) sequence, and the root index is a logical index for the UE to generate 64 candidate random access preambles.

Transmission of the random access preamble is limited to a specific time and frequency resource for each cell. The PRACH configuration index indicates a specific subframe and a preamble format capable of transmitting the random access preamble.

The UE sends the randomly selected random access preamble to the eNodeB. The UE selects one of the 64 candidate random access preambles. Then, the corresponding subframe is selected by the PRACH configuration index. The UE transmits the selected random access preamble in the selected subframe.

Upon receiving the random access preamble, the eNodeB sends a random access response (RAR) to the UE. The random access response is detected in two steps. First, the UE detects a PDCCH masked with random access-RNTI (RA-RNTI). The UE receives a random access response in a medium access control (MAC) protocol data unit (PDU) on the PDSCH indicated by the detected PDCCH.

6 shows a connection process in a radio resource control (RRC) layer.

As shown in FIG. 6, the RRC state is shown depending on whether the RRC is connected. The RRC state refers to whether or not an entity of the RRC layer of the UE is in a logical connection with an entity of the RRC layer of the eNodeB. When the RRC state is connected, the RRC state is referred to as an RRC connected state. The non-state is called the RRC idle state.

Since the UE in the connected state has an RRC connection, the E-UTRAN may determine the existence of the corresponding UE in units of cells, and thus may effectively control the UE. On the other hand, the UE in the idle state (idle state) can not be identified by the eNodeB, the core network is managed by the tracking area (Tracking Area) unit that is larger than the cell unit. The tracking area is a collection unit of cells. That is, the idle state (UE) is determined only in the presence of the UE in a large area, and in order to receive a normal mobile communication service such as voice or data, the UE must transition to the connected state (connected state).

When a user first powers up a UE, the UE first searches for an appropriate cell and then stays idle in that cell. When the UE staying in the idle state needs to establish an RRC connection, the UE establishes an RRC connection with the RRC layer of the eNodeB through an RRC connection procedure and transitions to an RRC connected state. .

There are various cases in which the UE in the idle state needs to establish an RRC connection. For example, a user's call attempt or an uplink data transmission is necessary, or a paging message is received from EUTRAN. In this case, the response message may be transmitted.

In order to establish an RRC connection with the eNodeB, a UE in an idle state must proceed with an RRC connection procedure as described above. The RRC connection process is largely a process in which a UE sends an RRC connection request message to an eNodeB, an eNodeB sends an RRC connection setup message to the UE, and a UE completes RRC connection setup to the eNodeB. (RRC connection setup complete) message is sent. This process will be described in more detail with reference to FIG. 6 as follows.

1) When the UE in idle state attempts to establish an RRC connection due to a call attempt, a data transmission attempt, or a response to an eNodeB's paging, the UE first sends an RRC connection request message. Send to eNodeB.

2) When the RRC connection request message is received from the UE, the eNB accepts the RRC connection request of the UE when the radio resources are sufficient, and transmits an RRC connection setup message, which is a response message, to the UE. .

3) When the UE receives the RRC connection setup message, it transmits an RRC connection setup complete message to the eNodeB. When the UE successfully transmits an RRC connection establishment message, the UE establishes an RRC connection with the eNodeB and transitions to the RRC connected mode.

ProSe (Proximity Service)

The processor service refers to a service capable of discovery and direct communication between devices in close physical proximity, communication through a base station, or communication through a third device.

FIG. 7 illustrates a default data path through which two UEs communicate in EPS. This basic route goes through the operator's base station (eNodeB) and the core network (ie, EPC). In the present invention, such a path will be referred to as an infrastructure data path (or EPC path). In addition, communication through such an infrastructure data path will be referred to as infrastructure communication.

8 shows a direct mode data path between two UEs based on a process. This direct mode communication path does not go through an eNodeB and a core network (ie, EPC) operated by an operator. FIG. 8 (a) illustrates a case where UE-1 and UE-2 camp on different eNodeBs while transmitting and receiving data through a direct mode communication path. FIG. 8 (b) illustrates camping on the same eNodeB. FIG. 2 illustrates a case in which two UEs that are on exchange data via a direct mode communication path.

FIG. 9 shows a locally-routed data path through an eNodeB between two UEs based on a process. The communication path through the eNodeB does not go through the core network (ie, EPC) operated by the operator.

10 shows a Non-Roaming Reference Architecture. In the structure as shown in FIG. 10, the EPC may perform an EPC-level ProSe discovery procedure for determining whether proximity between two UEs and informing the UE of this. For such EPC-level ProSe discovery, ProSe Function is to determine whether two UEs are in close proximity and to inform the UE.

The ProSe function retrievals and stores process associated subscriber data and / or processor associated subscriber data from the HSS, and performs EPC level process discovery and EPC secondary WLAN direct discovery, authentication and configuration for communication. Can be. It can also operate as a location service client to enable EPC level discovery and provide the UE with information to assist in WLAN direct discovery and communication. Handles EPC ProSe User IDs and Application Layer User IDs, and exchanges signals with 3rd party application servers for application registration identifier mapping. It exchanges signals with ProSe functions of other PLMNs for transmission of proximity requests, proximity alerts, and location reporting.

11 illustrates a procedure related to a proximity request.

In detail, in step S1101, UE A may transmit a proximity request message to ProSe Function A. The proximity request may include one or more of EPUID_A, Application ID, ALUID_A, ALUID_B, window, Range, A's location, and [WLAN indication]. The Application ID parameter may identify a 3rd party App Server platform. ALUID_A and ALUID_B are user IDs for users A and B of the application layer. The window parameter indicates the time interval for which the request is valid. Range is the range for this application, selected from the set of allowed range classes. The window information may be a value between 1 and 1440 minutes. The range information may indicate one of 50 m, 100 m, 200 m, 500 m, and 1000 m (see TS 24.334 for details). A's location is the current location of UE A. UE A may optionally request EPC support for direct discovery and communication by adding WLAN indications. In step S1102, ProSe Function A transmits a Map Request (ALUID_A, ALUID_B) to the App Server providing the EPC ProSe User ID. ProSe Function A stores Application Layer User IDs (ALUID_A and ALUID_B) until a Proximity Alert procedure or Proximity Request Cancellation procedure is performed or until the window expires. In step S1103, the App Server checks the application specific process permission of user B 'and confirms that User A is allowed to discover User B. In addition to EPC ProSe User ID (EPUID_B) of user B, ProSe Function A sends a Map Response (EPUID_B PFID_B) indicating the ProSe Function ID of ProSe Function B (PFID_B). ProSe Function A stores EPUID_B and PFID_B until a proximity proximity alert procedure or a proximity request cancellation procedure or a window expires. In step S1104, ProSe Function A propagates a proximity request (EPUID_B, EPUID_A, Application ID, window, A's location, [WLLID_A]) message to ProSe Function B. In step S1105, based on the received EPUID_B, the recording of the ProSe Function B subscriber B is retried. ProSe Function B may request the HSS for the last position of UE B (step S1105a). Based on the location of UE A and the last location of UE B, ProSe Function B may determine whether two UEs may enter a proximity relationship until the window expires. If it is determined that the proximity relationship cannot be entered, the proximity request rejection may be transmitted with an appropriate reason value (steps S1105b and c). In step S1106, according to the ProSe profile of the UE B, it may request that the UE B confirm the permission for the process request sent by the UE A. In step S1107a, b, ProSe Function B transmits the location report request of UE B to SLP B, and transmits a proximity request ACK to ProSe Function A. If UE B uses a permanent WLAN link layer ID, and UE A requested EPC support for WLAN direct discovery and communication, the WLAN link layer ID (WLLID_B) of UE B is included. In step S1108a ProSe Function A transmits a location report request to SLP A. If it is difficult to enter the proximity within the window, ProSe Function A may decide to cancel the proximity request. Otherwise, ProSe Function A sends a proximity request ACK to UE A.

12 illustrates a procedure related to UE location reporting. Referring to FIG. 12, the positions of UE A and UE B are reported intermittently to each SLP (steps S1201 and 1203). In addition, SLP A and SLP B report positions to ProSe Functions A and B, respectively (steps S1202 and S1204). When ProSe Function A determines proximity between UE A and UE B, ProSe Function B determines the position of UE B as ProSe. Send to Function A on a periodic and / or trigger basis.

13 shows a procedure for proximity alert (Proximity Alert). When the UE enters proximity (relationship), the network triggers a proximity alert procedure. Through steps S1301 to S1303, the location of UE B is delivered to ProSe Function A. In step S1304a, ProSe Function A detects that two UEs are in proximity (relationship) based on the requested discovery range class. In step S1304b, the UE A transmits a proximity alert (Application ID, ALUID_B, Assistance Information). If UE A requests EPC support for WLAN direct discovery and communication, ProSe Function A may request ProSe Function B to send a proximity alert (Application ID, ALUID_A, Assistance Information) to UE B (steps S1305a-b). In step S1305c ~ d ProSe Function A and ProSe Function B cancels the location report request for UE A and UE B to SLP A and SLP B, respectively. If UE A has not requested EPC support for WLAN direct discovery and communication, in step S1306 ProSe Function A may initiate a cancellation of the process request by sending Cancel Proximity Request (EPUID_B, EPUID_A) to ProSe Function B. See FIG. 14 for a procedure related to canceling a process request.

Referring to FIG. 14, in step S1401, UE A may transmit a Cancel Proximity Request (EPUID_A, Application ID, ALUID_B) to Prose Function A. Prose Function A may send Cancel Proximity Request (EPUID_B, EPUID_A) to Prose Function B. In step S1403, Prose Function A sends cancels location reporting to the SLP. In step S1406, Prose Function A transmits Proximity Request Cancellation (Application ID, ALUID_B) to UE A.

Content not explicitly mentioned in the description of FIGS. 11 to 14 is referred to by the 3GPP TS 23.303 document.

In conventional ProSe discovery, a UE transmits a proximity request including a window to a ProSe Function, and if two UEs do not enter the proximity relationship until this window expires, the ProSe Function cancels the location report request to the SLP. In addition, the UE that performed the proximity request is informed that the proximity request has been cancelled. Referring back to FIG. 14, ProSe Function A serving UE A cancels a proximity request to ProSe Function B serving UE B (S1402), and requests a location reporting for UE A requested to SLP A. Cancel (S1403), and inform the UE A that the proximity request has been canceled (S1406). That is, UE A is informed that it is not in close proximity to UE B within the time window. ProSe Function B cancels the location report request for UE B that has previously requested to SLP B and ack a cancellation to ProSe Function A (S1404-S1405).

This conventional ProSe discovery does not take into account the situation where two UEs may be in close proximity immediately after a time window expires or after a short time (eg, within minutes). Although two UEs may not be in proximity within the time window, they may be in a proximity soon or shortly, thereby providing a better ProSe experience for users seeking to find other UEs / users by notifying the UE. Not considering Accordingly, the present invention provides an enhanced or extended ProSe discovery (or improved ProSe discovery) mechanism.

향상된 ProSe 디스커버리를 위한 ProSe Function의 동작ProSe Function Behavior for Enhanced ProSe Discovery

The ProSe function that receives a proximity request from the discoverer UE, including the window and the range, determines whether the discoverer UE enters a proximity relationship with the discoverer UE until the window expires. Can be. If the window cannot be entered into the proximity until the window expires, as described above, the discovery cancels the proximity request to the ProSe function related to the UE and sends a location report request requested to the SLP related to the discoverer UE. Cancel and notify the discovery UE that the proximity request has been cancelled.

If the ProSe function decides to perform an enhanced ProSe discovery operation, the ProSe function does not cancel location reporting even when the window expires. The location report may be an intermittent location report. In addition, discovery does not cancel the proximity request to the ProSe function related to the UE. In addition, the discovery UE is not informed that the proximity request has been cancelled. (More details on this will be described later.)

Here, the determination of whether to perform the enhanced ProSe discovery operation may be performed as follows.

As an example, the proximity request may include time information α related to enhanced ProSe discovery. In this case, the time information may be time information for allowing a ProSe function, which will be described later, to determine whether to perform an enhanced ProSe discovery operation. In this case, the ProSe function may determine whether to perform an enhanced ProSe discovery operation based on the window β, the range γ, and the distance δ determined from the time information α related to the ProSe discovery. Here, the determined distance δ may be determined by {α / β} * γ. Specifically, when the distance between the discoverer UE and the discovery UE is within the sum of the determined distance δ and range γ, it may be determined to perform an enhanced ProSe discovery operation (for α time). The ProSe function may consider various information such as moving speeds of two UEs for calculating the δ value. For example, when alpha = 15 minutes, beta = 60 minutes, and gamma = 200 m, the value of? When 60 minutes have elapsed and the distance between the two UEs is within 200 + 50 m, the ProSe function may determine to perform an enhanced ProSe discovery operation.

As another example, the proximity request may include distance information m related to enhanced ProSe discovery. The distance information may be distance information between a discovery UE and a discovery UE, which will allow a ProSe function to be described later to determine whether to perform an enhanced ProSe discovery operation. The ProSe function may determine to perform the enhanced ProSe discovery operation for a time t determined from the window β, range γ, and distance information m related to the enhanced ProSe discovery, wherein the determined time t ) May be determined by {m / γ} * β. The ProSe Function may consider various information such as moving speeds of two UEs for calculating the t value. As a specific example, for example, when m = 20 m, γ = 200 m, and β = 120 minutes, the value of t is 12 minutes since {m / γ} * β = {1/10} * 120 minutes. Accordingly, if 120 minutes have elapsed while the two UEs are not in close proximity, the ProSe function may determine to perform an enhanced ProSe discovery operation for 12 minutes.

As another example, if the distance between two UEs is within a distance corresponding to {γ * (100% + x%)}, the ProSe Function may be configured to allow the discoverer UE and the discovery UE to not be in close proximity. Although the provided time window has expired / exceeds, it may be determined that an enhanced ProSe discovery operation should be performed for α time. For example, assuming that β = 60 minutes, γ = 500m and x = 5%, {500 * (100% + 5%)} = 525m. When 60 minutes have elapsed and the distance between the two UEs is within 525m, the ProSe function may determine to perform an enhanced ProSe discovery operation. The x value may be set in the ProSe Function or may be set in consideration of various information such as α, β, and γ values, and moving speeds of two UEs.

As another example, if the discoverer UE and the discovery UE are not in close proximity and the time window provided by the discoverer UE expires / exceeds, the ProSe function is improved for a time equal to {β * γ%}. It may be determined that a ProSe discovery operation should be performed. For example, when β = 90 minutes and γ = 10%, {90 * 10%} = 9 minutes. If 90 minutes have elapsed and the two UEs are not in close proximity, the ProSe Function may determine to perform an enhanced ProSe discovery operation for 9 minutes. The γ value may be set in the ProSe Function, or may be set in consideration of various information such as m, γ, β values, and moving speeds of two UEs.

Alternatively, the determination of whether to perform an enhanced ProSe discovery operation may be performed based on various information presented in the present invention, information conventionally provided when a discovery UE transmits a proximity request message, conventional information set in a ProSe function, and / or Or information about a discovery UE and a discovery UE that ProSe Function has (eg, distance information between two UEs and / or location information of two UEs, and / or movement information of two UEs, and / or a history of movement of two UEs) Information, etc.). For example, if the time information value for determining whether or not to perform an enhanced ProSe discovery operation is 10 minutes, and the discovery UE is located within 200 m upon the proximity request, the proximity request is requested, and the distance between the two UEs is currently 202 m. The ProSe Function may determine that an enhanced ProSe discovery operation should be performed. That is, in this case, the ProSe Function may determine that two UEs may be in a proximity relationship within 10 minutes.

In addition, the determination of whether to perform the enhanced ProSe discovery operation may be determined based on one or more of the information listed in Table 2 below.

TABLE 2

i) information provided by the discoverer UE specified in [1] ii) subscriber information of the discoverer UE (which can be obtained from the HSS via the PC4a interface) iii) application-related information of the discoverer UE Can be obtained from the ProSe Application Server via the PC2 interface) iv) Configuration information set within the ProSe Function, one or more of the following: information indicating that an enhanced (Enhanced or Extended) ProSe discovery operation should be performed. Information indicating that the discoverer UE and discovery should inform the discoverer UE when the UE is in close proximity-time window information to perform enhanced ProSe discovery operations-perform enhanced ProSe discovery operations Time information to decide whether or not to: The time information may be actual time (eg x seconds, y minutes, etc.) And range class information of time (e.g., upcoming / immediately, within seconds, within minutes, etc.)-Distance information between the discovery UE and the discovery UE to determine whether to perform an enhanced ProSe discovery operation: The distance information may be geographical distance information (eg, x meter) or range class information (eg, short, medium, maximum, etc.) of the distance.

Subsequently, if the ProSe function determines to perform an enhanced ProSe discovery operation, the ProSe function does not cancel the location reporting operation for the UE that has previously requested the SLP. To this end, the ProSe Function, that is, the ProSe Function serving the discoverer UE, does not cancel the location reporting operation requested by the SLP to obtain the location information of the discoverer UE. That is to keep it. This may be expressed as not performing step S1403 in FIG. 14. In addition, the ProSe Function may enable the ProSe Function for serving the UE not to cancel the location reporting operation requested by the SLP to obtain the location information of the UE. That is to keep it. This may be expressed as not performing the step S1402, but a separate message may be transmitted for this purpose.

Alternatively, when the ProSe Function notifies the discovery UE that the proximity request has been cancelled, the ProSe function may include enhanced ProSe discovery related information. That is, when performing step S1406 in FIG. 14, the enhanced ProSe discovery related information is included. Alternatively, instead of notifying the discovery UE that the proximity request has been canceled, the ProSe Function may transmit a message for notifying the enhanced ProSe discovery related information. That is, instead of performing step S1406, that is, instead of transmitting a proximity request cancellation message, another message (eg, a message newly defined for the present invention) may be transmitted. The enhanced ProSe discovery related information may include one or more of the information listed in Table 3 below. It may be delivered explicitly, implicitly, or may be provided in a combined form.

TABLE 3

-Information indicating that an enhanced ProSe discovery operation is being performed-information indicating that the discovery UE may be in proximity with (or likely to be in) proximity to the UE-performing an enhanced ProSe discovery operation (continued) Information requesting to respond whether or not to do-information on the current distance between the discovery UE and the discovery UE

Based on the time window information to perform the enhanced ProSe discovery operation, if the discovery UE and the discovery UE are in proximity within this time, the ProSe function may perform a proximity alert operation. This operation may be the procedure illustrated in FIG. 13. When the ProSe Function transmits a Proximity Alert message to the discoverer UE, the ProSe Function may additionally include information indicating that the alert message is a result of an enhanced ProSe discovery operation.

Or, based on the time window information to perform the enhanced ProSe discovery operation, if the discovery UE and the discovery UE are not in close proximity even after this time expires / exceeds, the ProSe function may request as shown in FIG. 14. The cancellation operation can be performed.

향상된 ProSe 디스커버리를 위한 UE의 동작UE Behavior for Enhanced ProSe Discovery

The UE performing the proximity request (ie, the discovery UE) may additionally include one or more of the information listed in Table 4 below in the proximity request message when transmitting the proximity request (S1101 of FIG. 11). The following information may be explicit or implicit, or in combination with each other.

Table 4

Information requesting to perform an enhanced (Enhanced or Extended) ProSe discovery operation (for reference, the enhanced ProSe discovery operation refers to the operation of the UE and / or the operation of the ProSe function proposed in the present invention); When exceeded, the information requesting to be informed when the UE (ie discovery is in close proximity to the UE) is looking for-information about the time window to perform an enhanced ProSe discovery operation-whether the ProSe Function should perform an enhanced ProSe discovery operation. Time information to determine whether or not: The time information may be actual time (e.g., x seconds, y minutes, z hours, etc.), or range class information of time (e.g. soon / immediately, within seconds, within minutes, number And a discovery UE that allows the ProSe Function to determine whether to perform an enhanced ProSe discovery operation. Discovery distance information between UEs: The distance information may be geographical distance information (eg, x meters) or range class information (eg, short, medium, maximum, etc.) of the distance.

In the above description, 'time window information for performing an enhanced ProSe discovery operation and time information for allowing a ProSe function to decide whether to perform an enhanced ProSe discovery operation' may be provided as one to include both meanings.

The discoverer UE that receives the enhanced ProSe discovery related information from the ProSe Function may receive the enhanced ProSe discovery related information from the ProSe Function. The discoverer UE receiving this may perform one or more of the following operations.

First, a response to information requesting to respond whether to perform an enhanced ProSe discovery operation (continued) may be transmitted to the ProSe Function. In this case, the UE may also transmit time window information for performing an enhanced ProSe discovery operation. To this end, the conventional proximity request message may be extended and used, or a new message may be defined and used.

Secondly, we can request a new ProSe discovery from the ProSe Function. That is, a new proximity request message can be sent to the ProSe Function.

The above description is not limited to LTE / EPC networks, but is applicable to all UMTS / EPS mobile communication systems including both 3GPP access networks (eg, UTRAN / GERAN / E-UTRAN) and non-3GPP access networks (eg, WLAN, etc.). Can be. In addition, it can be applied in all other wireless mobile communication system environments in the environment where control of the network is applied.

15 is a diagram showing the configuration of a preferred embodiment of a terminal device and a network node device according to an example of the present invention.

The terminal device 100 according to the present invention with reference to FIG. 15 may include a transmission / reception module 110, a processor 120, and a memory 130. The transmission / reception module 110 may be configured to transmit various signals, data, and information to an external device, and receive various signals, data, and information to an external device. The terminal device 100 may be connected to an external device by wire and / or wirelessly. The processor 120 may control the overall operation of the terminal device 100, and may be configured to perform a function of the terminal device 100 to process and process information to be transmitted and received with an external device. In addition, the processor 120 may be configured to perform a terminal operation proposed in the present invention. The memory 130 may store the processed information for a predetermined time and may be replaced with a component such as a buffer (not shown).

Referring to FIG. 15, the network node device 200 according to the present invention may include a transmission / reception module 210, a processor 220, and a memory 230. The transmission / reception module 210 may be configured to transmit various signals, data, and information to an external device, and receive various signals, data, and information to an external device. The network node device 200 may be connected to an external device by wire and / or wirelessly. The processor 220 may control the overall operation of the network node device 200, and may be configured to perform a function of calculating and processing information to be transmitted / received with an external device. In addition, the processor 220 may be configured to perform the network node operation proposed in the present invention. The memory 230 may store the processed information for a predetermined time and may be replaced with a component such as a buffer (not shown).

In addition, the specific configuration of the terminal device 100 and the network device 200 as described above, may be implemented so that the above-described matters described in various embodiments of the present invention can be applied independently or two or more embodiments are applied at the same time, overlapping The description is omitted for clarity.

Embodiments of the present invention described above may be implemented through various means. For example, embodiments of the present invention may be implemented by hardware, firmware, software, or a combination thereof.

For implementation in hardware, a method according to embodiments of the present invention may include one or more Application Specific Integrated Circuits (ASICs), Digital Signal Processors (DSPs), Digital Signal Processing Devices (DSPDs), and Programmable Logic Devices (PLDs). It may be implemented by field programmable gate arrays (FPGAs), processors, controllers, microcontrollers, microprocessors, and the like.

In the case of an implementation by firmware or software, the method according to the embodiments of the present invention may be implemented in the form of a module, a procedure, or a function that performs the functions or operations described above. The software code may be stored in a memory unit and driven by a processor. The memory unit may be located inside or outside the processor, and may exchange data with the processor by various known means.

The detailed description of the preferred embodiments of the invention disclosed as described above is provided to enable any person skilled in the art to make and practice the invention. Although the above has been described with reference to the preferred embodiments of the present invention, those skilled in the art will variously modify and change the present invention without departing from the spirit and scope of the invention as set forth in the claims below. I can understand that you can. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Various embodiments of the present invention as described above have been described with reference to the 3GPP system, but may be applied to various mobile communication systems in the same manner.

Claims

In a method for ProSe function to perform ProSe discovery in a wireless communication system,

Receiving, from the discoverer UE, a proximity request comprising a window and a range;

Determining, by the discoverer UE, that the discovery UE will enter a proximity relationship with the UE until the window expires;

Including;

If the ProSe function determines to perform an enhanced ProSe discovery operation, the ProSe function does not cancel location reporting even when the window expires.
The method of claim 1,

If the proximity request includes time information α related to enhanced ProSe discovery,

The ProSe function determines whether to perform the enhanced ProSe discovery operation based on the window β, the range γ, and the distance δ determined from the time information α related to the ProSe discovery. Way.
The method of claim 2,

The determined distance (δ) is determined by {α / β} * γ, discovery method.
The method of claim 3,

And if the distance between the discovery UE and the discovery UE is within the sum of the determined distance δ and range γ, determine that the enhanced ProSe discovery operation is to be performed.
The method of claim 1,

If the proximity request includes distance information (m) related to enhanced ProSe discovery,

And the ProSe function determines to perform the enhanced ProSe discovery operation for a time t determined from the window (β), range (γ) and distance information (m) related to the enhanced ProSe discovery.
The method of claim 1,

The determined time (t) is determined by {m / γ} * β, the discovery method.
A ProSe function device for performing ProSe discovery in a wireless communication system,

A transceiver module; And

Includes a processor,

The processor receives, from a discoverer UE, a proximity request comprising a window and a range, and determines whether the discoverer UE enters a proximity relationship with the UE until the window expires. ,

And if the ProSe function determines to perform an enhanced ProSe discovery operation, the ProSe function does not cancel location reporting even when the window expires.
The method of claim 7, wherein

If the proximity request includes time information α related to enhanced ProSe discovery,

The ProSe function determines whether to perform the enhanced ProSe discovery operation based on the window β, the range γ, and the distance δ determined from the time information α related to the ProSe discovery. Device.
The method of claim 8,

The determined distance δ is determined by {α / β} * γ, ProSe function device.
The method of claim 9,

And determine that the enhanced ProSe discovery operation is performed when the distance between the discoverer UE and the discovery UE is within the sum of the determined distance δ and range γ.
The method of claim 7, wherein

If the proximity request includes distance information (m) related to enhanced ProSe discovery,

And the ProSe function determines to perform the enhanced ProSe discovery operation for a time t determined from the window (β), range (γ), and distance information (m) related to the enhanced ProSe discovery.
The method of claim 7, wherein

The determined time (t) is determined by {m / γ} * β, ProSe function device.