CN108184222B

CN108184222B - Network entity and method for discovering among devices suitable for network entity

Info

Publication number: CN108184222B
Application number: CN201810101372.1A
Authority: CN
Inventors: 辛伯修; 郑延修
Original assignee: Industrial Technology Research Institute ITRI
Current assignee: Industrial Technology Research Institute ITRI
Priority date: 2014-01-13
Filing date: 2015-01-05
Publication date: 2020-10-27
Anticipated expiration: 2035-01-05
Also published as: CN104780497A; CN108184222A; CN104780497B

Abstract

The present invention relates to a network entity and an inter-device discovery method applicable to the network entity. The network entity includes: and the transmitter is used for transmitting data. A receiver for receiving data. A processing circuit coupled to the transmitter and the receiver and configured to: receiving, via the receiver, a first cancel proximity request comprising a network level discoverer identifier, an application identifier and an application level discoverer identifier; transmitting, via the transmitter, a second cancel proximity request including the network level discoverer identifier and a network level discoverer identifier in response to the received first cancel proximity request; receiving, via the receiver, a first acknowledgement signal corresponding to the second cancel proximity request in response to the transmitted second cancel proximity request; and transmitting, via the transmitter, a second acknowledgement signal corresponding to the first cancel proximity request in response to the received first acknowledgement signal.

Description

Network entity and method for discovering among devices suitable for network entity

The present application is a divisional application of a patent application having an application date of 2015, 1-5, application number of 201510001689.4, entitled "inter-device discovery method for user equipment and network entity".

Technical Field

The present invention relates to a device-to-device (D2D) discovery method applicable to a User Equipment (UE) and a network entity (network entity), and a UE and a network entity using the same.

Background

When a UE seeks discovery or discovery, a proximity based service (ProSe) or D2D discovery procedure (discovery process) is typically required. The ProSe discovery procedure is a procedure of identifying whether a ProSe-enabled discoverer (discoverer) UE is adjacent to another ProSe-enabled discoverer (discoveree) UE, with or without assistance from an Evolved Packet Core (EPC), which is considered a Core network for a Long Term Evolution (LTE) communication system. The Network assistance may or may not involve Evolved Universal Radio Access Network (E-UTRAN). A UE may be said to be adjacent to another UE whenever the UE complies with proximity criteria with respect to the other UE. The proximity criterion may relate to at least a particular distance or a certain communication range class and may be different for the discovery process and any subsequent communication phases.

When the ProSe discovery process occurs in the EPC level, the ProSe discovery process will involve a discovery procedure by which the EPC determines the proximity of two ProSe-capable UEs and informs the UEs of their proximity. ProSe-capable UEs refer to UEs that support current ProSe requirements and associated procedures [ see 3GPP TS 32.278 ]. The ProSe-capable UE may also be a non-public safety UE (e.g., a UE with commercial applications), a public safety UE, or both. Each ProSe-capable UE may have a range class (range class), which is a rough indication of distance used in ProSe discovery, e.g., based on geographic distance, radio conditions.

The ProSe discovery process may involve different types of Identifiers (IDs). The EPC ProSe user ID is an EPC-level ProSe discovery and EPC-supported identifier for Wireless Local Area Network (WLAN) direct communication, and is used to uniquely identify a UE registered for ProSe. Such identifiers may be occasionally reassigned by ProSe functions in the EPC network. The ProSe function ID is a Fully Qualified Domain Name (FQDN) that uniquely identifies the ProSe function. The application ID is a globally unique identifier that identifies a particular application. The application layer user ID is an identifier that identifies the user within the context of a particular application. The WLAN link layer ID is a link layer identity used for WLAN direct discovery and/or WLAN direct communication. The WLAN link layer ID may be temporary (e.g., a temporary MAC address) or permanent (e.g., a permanent MAC address).

D2D communication, proximity communication, or ProSe communication are new technical features currently being developed in third generation partnership project (3GPP) release 12 and release 13. There may be at least two main practices for proximity discovery — EPC-level ProSe discovery (ProSe discovery) and ProSe direct discovery (ProSe direct discovery). The two findings may be complementary solutions, but may also be implemented independently. Fig. 1 illustrates an exemplary network architecture by which EPC-level discovery is handled. The entities may relate to a first user equipment 101 and a second user equipment 102, both user equipments being capable of ProSe applications or having ProSe capabilities. The entity may also relate to the E-UTRAN 103. The ProSe function 104 represents a D2D or ProSe function commonly supported by the EPC network. E-UTRAN103 is connected to Mobility Management Entity (MME) 105, and E-UTRAN103 may also be connected directly to ProSe function 104 within the EPC. The ProSe function 104 is connected to a secure User Plane location platform (SLP)106, wherein location information may be obtained or estimated via the secure User Plane location platform (SLP) 106. The ProSe function 104 may be connected to a ProSe application server 107, which may be a third party server (third party server) and is not an inherent part of the EPC network. The specific description of the aforementioned entities refers to the description of 3GPP Technical Specification (TS)23.303, and thus the description will not be repeated.

Fig. 2 shows a typical call flow for EPC-level ProSe discovery as in the standard draft (e.g., 3GPP TR 23.703 v1.0.0). The steps shown in fig. 2 will be briefly described as follows. In step S201, it is assumed that UE a performs UE registration for ProSe communication with ProSe function a residing in its respective home public land mobile network (home PLMNs). In step S202, UE B performs UE registration for ProSe with ProSe function B residing in its respective home PLMNs. Similarly, in steps S203 and S204, UE a and UE B perform ProSe application registration with ProSe function a and ProSe function B, respectively, in their home PLMNs. In step S205, UE a makes a proximity request reception appropriate response for UE B. For example, if UE B is adjacent to UE a within a predefined time window (time window), UE a may be alerted to the presence of UE B. In response to the proximity request, ProSe function a will request location updates for UE a and UE B. The location update may be periodic, or may be based on a triggered event, or both. To request a location update for UE a, ProSe function a will contact SUPL Location Platform (SLP) a. Likewise, to request a location update for UE B, ProSe function a will contact ProSe function B, which in turn will request a location update for UE B from SLP B.

In step S206, the ProSe function a receives a report of the location of UE a from SLP a. In step S207, the ProSe function B receives a report of the location of UE B from SLP B. The location of UE a and UE B may be intermittently reported to their respective ProSe functions. ProSe function B may forward an update of the location of UE B to ProSe function a based on the conditions set by ProSe function a. And, whenever ProSe function a receives a location update for UE a and/or UE B, ProSe function a may perform a proximity analysis of the location of UE a and UE B. In step S208, when ProSe function a detects that UE a and UE B are proximate, ProSe function a will notify UE a of UE B proximity and may optionally provide UE a with assistance information for WLAN direct discovery and communication with UE B. Likewise, ProSe function a also notifies ProSe function B, which in turn notifies UE B that it detected the proximity of UE a. The ProSe function B may also optionally provide assistance information to UE B for WLAN direct discovery and communication with UE a.

Disclosure of Invention

Accordingly, the present invention relates to a D2D discovery method applicable to UEs and network entities and UEs and network entities using the same.

In one aspect of the invention, the invention relates to a D2D discovery method applicable to a UE, including at least but not limited to: initiating a D2D discovery process and having a first window value, wherein the first window value represents a time window and is a positive number; transmitting a first proximity discovery request including the first window value; canceling the D2D discovery process by detecting a cancellation event in response to the transmitted first proximity discovery request; in response to the detected cancellation event, stopping the D2D discovery process if the first window value decreases to a certain threshold; and transmitting a first cancel proximity discovery request to cancel the D2D discovery procedure in response to the received cancel event if another proximity discovery request does not exist within the UE.

In another aspect of the present invention, the present invention relates to a UE, including at least, but not limited to; a transmitter for transmitting wireless data, a receiver for receiving wireless data, and processing circuitry coupled to the transmitter. The processing circuit is configured to: initiating a D2D discovery process and having a window value, wherein the window value represents a time window and is a positive number; transmitting a first proximity discovery request including the window value; canceling the D2D discovery process by detecting a cancellation event in response to the transmitted first proximity discovery request; in response to the detected cancellation event, stopping the D2D discovery process if the window value decreases to a certain threshold; and transmitting a cancel proximity discovery request to cancel the D2D discovery process in response to the received cancel event if another proximity discovery request is not present within the UE.

In another aspect of the invention, the invention relates to a D2D discovery method applicable to a network entity, including at least but not limited to: receiving a first proximity discovery request to perform a network assisted (network assisted) D2D discovery procedure, wherein the first proximity discovery request includes a first window value, the first window value being a non-negative number; performing proximity estimation and User Equipment (UE) state estimation in response to the received first proximity discovery request; canceling the network assisted D2D discovery process in response to the proximity estimation and the UE state estimation performed, wherein canceling the network assisted D2D discovery process includes transmitting a cancel proximity discovery request and transmitting a cancel location report request.

In another aspect of the invention, the invention relates to a network entity comprising at least, but not limited to: a transmitter for transmitting a signal, a receiver for receiving a signal, and processing circuitry coupled to the transmitter and the receiver. The processing circuit is configured to: receiving, via the receiver, a first cancel proximity request comprising a network level discoverer Identifier (ID), an application ID, and an application level discoverer ID; transmitting, via the transmitter, a second cancel proximity request including the network level discoverer ID and a network level discoverer ID in response to the received first cancel proximity request; receiving, via the receiver, a first acknowledgement signal corresponding to the second cancel proximity request in response to the transmitted second cancel proximity request; and transmitting, via the transmitter, a second acknowledgement signal corresponding to the first cancel proximity request in response to the received first acknowledgement signal.

In another aspect of the invention, the invention relates to a D2D discovery method applicable to a network entity, including at least but not limited to: receiving a first cancel proximity request comprising a network-level discoverer Identifier (ID), an application ID, and an application-level discoverer ID; transmitting a second cancel proximity request including the network level discoverer ID and a network level discoverer ID in response to the received first cancel proximity request; receiving a first acknowledgement signal corresponding to the second cancel proximity request in response to the transmitted second cancel proximity request; and transmitting a second acknowledgement signal corresponding to the first cancel proximity request in response to receiving the first acknowledgement signal.

In order that the above features and advantages of the present invention may be understood, exemplary embodiments provided with the accompanying drawings are described in detail below. It is to be understood that both the foregoing general description and the following detailed description are exemplary, and are intended to provide further explanation of the invention as claimed.

It should be understood, however, that this summary may not contain all aspects and embodiments of the invention, and thus should not be construed as limiting the invention. Moreover, the scope of the present invention should encompass improvements and modifications apparent to those skilled in the art.

Drawings

The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

Fig. 1 is an exemplary network architecture by which EPC-level discovery is handled.

Fig. 2 is a general call flow for EPC-level ProSe discovery.

Fig. 3 is a flow diagram illustrating a network assisted ProSe discovery procedure from the perspective of a ProSe capable UE in an exemplary embodiment in accordance with the invention.

Fig. 4 is a cancellation procedure of ProSe discovery procedure initiated by a ProSe-capable UE in an exemplary embodiment in accordance with the invention.

Fig. 5 is a cancellation procedure (cancellation procedure) of a UE-initiated ProSe discovery procedure in another exemplary embodiment according to the present invention.

Fig. 6 is a flow diagram of an EPC-level ProSe discovery process assisted by a network entity in accordance with one of the exemplary embodiments of the present invention.

Fig. 7 is a signaling diagram of a network assisted ProSe discovery procedure in an exemplary embodiment in accordance with the invention.

Fig. 8 is a method of inter-device (D2D) discovery shown from the perspective of a User Equipment (UE) in an exemplary embodiment according to the invention.

Fig. 9 is a method of inter-device (D2D) discovery shown from the perspective of a network node in an exemplary embodiment in accordance with the invention.

Fig. 10 is an exemplary UE according to the present disclosure.

Fig. 11 is an exemplary network entity according to the present disclosure.

Description of the figures

101: first user equipment

102: second user equipment

103: evolved universal terrestrial radio access network (E-UTRAN)

104: ProSe function

105: mobility Management Entity (MME)

106: secure user plane location platform (SLP)

107: ProSe application server

511：UE A

512: ProSe function A

513: application server

514：UE B

515: ProSe function B

516：SLP A

517：SLP B

611：UE A

612：UE B

613: ProSe function A

614: ProSe function B

616：SLP A

617：SLP B

851：UE A

852: ProSe function A

853: application server

854: ProSe function B

855：UE B

856: user attaching server (HSS)

857: mobility Management Entity (MME)

858：SLP B

859：SLP A

1101: processing circuit

1102: analog-to-digital converter/digital-to-analog converter

1103: emitter

1104: receiver with a plurality of receivers

1105: antenna unit

1201: processing circuit

1202: communication protocol circuit

1203: emitter

1204: receiver with a plurality of receivers

LTE-Uu, PC1, PC2, PC3, PC4a, PC4b, PC5, S1, S6 a: interface

S201 to S208, S401 to S406, S501 to S506, S601 to S604, S701 to S709, S801 to S812, S901 to S905, S1001 to S1003, S1004a, S1004 b: step (ii) of

Detailed Description

Reference will now be made in detail to exemplary embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings and the description to refer to the same or like parts.

The present invention proposes a ProSe discovery procedure applicable to UE and network entities. The invention also proposes a UE and a network entity using the ProSe discovery procedure. The provision of the present invention involves enabling ProSe-capable UEs and ProSe-capable network entities (e.g., ProSe functions) to dynamically stop ProSe discovery procedures based on application needs and network conditions, as well as user preferences and settings. The aforementioned ProSe function is, for example, an entity within the core network such as EPC, and may provide proximity services. Exemplary embodiments of the present invention will also include minimizing network signaling related to proximity estimation and avoiding unnecessary computational power related to location updates and proximity estimation.

The proposed exemplary embodiment of the invention comprises two parts which can be implemented in whole or separately. One is a UE-based switching procedure (hand-taking procedure) designed to dynamically allow cancellation of ProSe discovery procedures even before the expiration of the originally set window value (window). Another is a modified network assisted procedure for dynamically terminating the ongoing ProSe discovery procedure. The proposed solution can be implemented by using the network architecture shown in fig. 1, but the signaling procedure (signaling procedure) and the functionality of the UE and ProSe functions have been modified. In particular, UE a may dynamically send a proximity request cancel command to the network entity, e.g., based on the ProSe function of fig. 3-5 and corresponding written description. By using cancellation signaling or appropriate parameters between the UE and network entities such as the ProSe function and location server, the UE can effectively terminate ongoing ProSe discovery procedures.

Fig. 3 is a flow chart illustrating a network assisted ProSe discovery procedure from the perspective of a UE in an exemplary embodiment in accordance with the invention. In step S401, after receiving an event trigger to initiate (initiate) the ProSe discovery procedure, the UE will transmit a proximity request to a network entity of the network (e.g., the ProSe function 104 of fig. 1). For example, an event trigger occurs when a user of a UE starts or restarts a ProSe application or ProSe-related application. The UE during the period indicated by the "window" value of the initial proximity request, the proximity request is used to detect whether another ProSe-capable D2D UE is or may be in proximity. The proximity request may, for example, be in accordance with a version of the LTE specification such as TR 23.703 v1.0.0. After receiving the proximity request, a network entity, such as the ProSe function 104, may initiate a ProSe discovery procedure. The proximity request may include an estimated window value such that the proximity request may remain valid until the window value expires, and the initiation and maintenance of the location report may also be performed during the period indicated by the window value.

In step S402, before the expiration of the window value, the UE determines whether any termination request is received, for example, a termination request triggered by the completion of the ProSe discovery procedure or a termination request from the application layer. If the termination request is not received, the UE will continuously wait for a proximity response (ProximityResponse) from the network in step S403 as long as the window value has not expired, or return to step S402, the UE will wait for the termination request from the application layer. The proximity response may include any value and may be consistent with the current LTE specifications (e.g., TR 23.703 v1.0.0). If a termination request has been received in step S402, the UE will determine whether the window value expires in step S404. If the window value has expired, the ProSe discovery procedure ends. If the window value has not expired, the UE will determine in step S405 whether there is another valid proximity request from another application or whether the UE has received another trigger event to enter the ProSe discovery procedure. If no further trigger event or proximity request has been received, the UE will signal the network entity to cancel the proximity request to the ProSe function in step S406. Otherwise, if it has been determined that another trigger event or proximity request has been received, the process continues in step S403. The cancellation procedure of the proposed ProSe discovery procedure as illustrated in fig. 3 may be implemented according to at least two exemplary embodiments of fig. 4, 5 and their corresponding written descriptions.

Fig. 4 is a procedure for canceling a UE-initiated ProSe discovery procedure in an exemplary embodiment in accordance with the present invention. The cancellation procedure of fig. 4 may correspond to step S406 of fig. 3. However, it is apparent to those skilled in the art that the cancellation procedure of fig. 4 may be independent of the discovery process in fig. 3, and thus may not correspond to step S406. In step S501, UE a511 transmits a first Cancel Proximity Request (Cancel Proximity Request) which is to be routed to a network entity, e.g. ProSe function a 512 of the EPC. The first cancel proximity request contains parameters not limited to EPSID _ a, application ID, ALUID _ a, and ALUID _ B, etc. The application ID identifies a third party application server platform or application server (App server) 513 of fig. 4. EPSID _ A is the ProSe subscriber ID of UE A511. ALUID _ A and ALUID _ B are the application layer user IDs of UE A511 and UE B514, respectively. After receiving the first cancel proximity request, the ProSe discovery procedure is processed to be cancelled by ProSe function a 512.

In step S502, in response to the received first cancel proximity request, ProSe function a 512 transmits a second cancel proximity request to ProSe function B515, in order to notify ProSe function B515 and subsequently SLP a 516 and SLP B517 of the cancel D2D proximity request initiated by UE a 511. The second cancel proximity request contains parameters not limited to EPSID _ A and EPSID _ B. EPSID _ B is the ProSe subscriber ID for UE B514. In step S503, in response to the received second cancel proximity Request, the ProSe function a 512 transmits a first cancel Location Services (LCS) Location Reporting Request (Location Reporting Request) to the SLP a 516 in order to cancel the Location report of the UE a 511. Similarly, in step S504, ProSe function B515 transmits a second cancel LCS location reporting request to SLP B517 to cancel the location reporting of UEB 514. In step S505, after receiving the second Cancel Proximity Request transmitted from the ProSe function a 512, the ProSe function B515 transmits a first Cancel Proximity Request acknowledgement (Cancel Proximity Request Ack) to the ProSe function a 512 so as to acknowledge the reception of the second Cancel Proximity Request signal. In response to the received first cancel proximity request acknowledgement, ProSe function a 512 transmits a second cancel proximity request acknowledgement to UE a511 to notify UE a511 of the acknowledgement of the first cancel proximity request signal in step S501.

Fig. 5 is a procedure for canceling a UE-initiated ProSe discovery procedure in another exemplary embodiment according to the present invention. The cancellation procedure of fig. 5 may correspond to step S401 or step S406 of fig. 3. In step S601, UE a611 transmits a first proximity request to ProSe function a 613. The first proximity request contains parameters not limited to EPSID _ a, application ID, ALUID _ A, ALUID _ B, "window", "range" (range class), "location of a" (location of UE a 611) and optionally "WLAN indicator". EPSID _ A, application ID, ALUID _ A, ALUID _ B, and "Range" are as previously described. The "window" value is a non-negative value that allows the network to handle (handle) proximity services for a specific time interval defined by or in relation to the "window" value. During this time interval, the network can track the location of the UE in real time and continue the interactive procedure between ProSe function B and ProSe function a, UE B, UE a and other related entities. The "window" value may be set to a predetermined value in order to inform cancellation or to further limit the duration of the ProSe discovery procedure. For example, the window value may be zero ("window" ═ 0), and the ProSe discovery will be effectively cancelled as step S404 is performed. The "WLAN indicator" is the WLAN link layer ID as previously described.

In step S602, in response to the received first proximity request, the ProSe function a613 transmits a second proximity request to the ProSe function B614. ProSe function B614 contains parameters not limited to EPSID _ A, EPSIB _ B, "window", "location of a" (location of UEA 611) and optionally "WLAN indicator". The "window" value may be set to a predetermined value in order to inform cancellation or to further limit the duration of the ProSe discovery procedure. In step S603, in response to the received second proximity request, the ProSe function B614 transmits a first cancel LCS location report request to the SLP B617 to cancel the update on the location report of the UE B612. Similarly, in step S604, in response to the received first proximity request, the ProSe function a613 transmits a second cancel LCS location reporting request to the SLP a616 in order to cancel the update of the location report of the UE a 611.

The network side may also assist the ProSe discovery cancellation procedure in response to a proximity request received from the UE. Basically, in response to a proximity request with an initial window value received from a UE, a network entity (e.g., a ProSe function) may terminate a ProSe discovery procedure in response to a detected specific parameter. The ProSe function will then perform subsequent procedures to derive the status and proximity of the UE based on the cell location or range class containing paging (paging) or obtaining the UE from the UE connection status recorded in the MME or from a location and/or application server. The ProSe function will then terminate the proximity discovery process and notify other ProSe functions and location servers of the termination process. The ProSe function may also notify the UEs of the cancellation by transmitting a proximity request cancellation message to the UEs. The details of the aforementioned network assisted ProSe discovery cancellation procedure proposed by the present invention are further illustrated by fig. 6 to 7 and their corresponding written descriptions.

Fig. 6 is a flow diagram of an EPC-level ProSe discovery process assisted by a network entity in an exemplary embodiment in accordance with the invention. The network entity may be a stand-alone entity (stand-alone entity) with a specific set of functionalities, or may be considered as a specific set of functionalities embedded in other entities of the core network. The network entity may be, for example, a ProSe function in EPC. In step S701, in response to receiving, by ProSe function a, UE a receiving a proximity request for UE B, ProSe function a will determine whether the "window" value in the proximity request has been set to a particular value. The "window" value may be set by the UE, and if the ProSe discovery procedure is to be terminated, the specific value may be set to zero ("window" ═ 0). If the ProSe function a has determined that the "window" value is set to zero, the ProSe function a transmits a ProSe cancellation request to the ProSe function B corresponding to the UE B in step S704. In step S705, the cancel request will also be sent to location server a (lcs a) and location server B (lcs B) corresponding to UE a and UE B in order to cancel the subsequent location update.

If the "window" value has not been set to zero in step S701, a network entity, e.g., ProSe function a or ProSe function B, will update the "window" value in step S702. In step S703, after updating the "window" value, ProSe function a and/or ProSe function B will obtain the status of the connection of UE B and the estimated location of UE B. In step S706, ProSe function a and/or ProSe function B will determine whether UE a and UE B are proximate or estimated to be proximate within the time period indicated by the "window" value based on, for example, an initial relative distance (i.e., range) between UE a and UE B or based on whether UE a and UE B are located within the same or different cells (cells). If UE a and UE B have been determined to be proximate or estimated to be approximately proximate, step S707 will be performed subsequently; otherwise, step S704 will be performed subsequently instead. If UE a and UE B are determined to be proximate, then in step S707 ProSe function a and/or ProSe function B will determine whether UE B is connected to the network. If UE B is connected, ProSe function a and/or ProSe function B will perform the subsequent proximity request procedure in step S708. If UE B is not connected, ProSe function a and/or ProSe function B will determine if UE B has been disconnected in step S709. If the UE B has been determined to be disconnected, step S704 will be performed. Otherwise, if UE B is not determined to be off, ProSe function a and/or ProSe function B will page (page) UE B in step S710 and then perform step S708.

Fig. 7 is a signaling diagram of a network assisted ProSe discovery procedure in an exemplary embodiment in accordance with the invention. In step S801, UE a851 transmits a first proximity request containing parameters not limited to EPSID _ a, application ID, ALUID _ A, ALUID _ B, "window", "range", "location of a" (location of UE a), and optionally a "WLAN indicator". The description of these parameters is the same as the previous description. In step S802, in response to the received first proximity Request, the ProSe function a852 may send a mapping Request (Map Request) containing parameters not limited to ALUID _ a and ALUID _ B to the ProSe application server 853 in order to Request the application server 853 to provide the EPC ProSe subscriber ID and ProSe function ID (pfid) of the target UE B855. The ProSe function a852 will store the application layer user IDs (ALUID _ a and ALUID _ B) until execution of the proximity alert program or until expiration of a time window in which the proximity request remains valid.

Thereafter, application server 853 will check the application specific ProSe grant from UE B855 in order to ensure that UE a851 has been allowed to discover UE B855. When this is the case, the application server 853 sends a Map Response (Map Response) containing parameters not limited to EPSID _ B and PFID _ B, which is the ProSe function ID of the ProSe function B854, to the ProSe function a852 in step S803. In step S804, the ProSe function a852 transmits a second proximity request based on the first proximity request to the ProSe function B854. The second proximity request contains parameters not limited to EPSID _ A, EPSIB _ B, "Window", "location of A" (location of UE A851), and optionally "WLAN indicator".

In step S805, the ProSe function B854 may perform proximity estimation (proximity estimation). For example, based on EPSID _ B received in step S804, ProSe function B854 may retrieve a subscriber record for UE B855. For example, ProSe function B854 may implement a UE location query via a user Home Server (HSS) 856 requesting the last known location of UE B855. In step S806, the ProSe function B854 may also obtain the connection status of UE B855 by transmitting a status request containing parameters not limited to the UE B ID, which is the ID of UE B855, to the Mobility Management Entity (MME) 857. In response to the transmitted status request message, ProSe function B854 will receive a status response from MME857 containing the ID of UE B855. The status response may indicate a UE connected status, e.g., idle status, detached status, and active status.

Based on the last known location of UE B855 obtained via HSS 856, the location and window values of UE a851 provided by ProSe function a852 in step S804 and the connection state of UE B855 in step S807, ProSe function B854 will perform proximity estimation and UE connection state decisions in step S808. Assuming that the ProSe function B854 has determined that it is not possible for UE a851 and UE B855 to be in proximity to each other within the requested time window or that UE B855 has been disconnected or is not possible to connect, the ProSe function B854 may decide to end the ProSe discovery procedure. In step S809, the ProSe function B854 may cancel the update of the location of the UE B855 by the SLP B858 by sending a cancel LCS location report request to the SLP B858. In step S810, the ProSe function B854 may transmit a cancel proximity request with an appropriate cause value to the ProSe function a852 in order to inform the ProSe function a852 that the ProSe discovery procedure is to be cancelled. In response to the received cancel proximity request message, the ProSe function a852 transmits a cancel LCS location report request to the SLP a 859 in order to cancel the update of the location of the UE a511 by the SLP a 859 in step S811. In step S812, the ProSe function a852 transmits a cancel proximity request with a cause value equal to the UE status to the UE a851 in order to inform the UE a851 that the ProSe discovery procedure has been cancelled.

Fig. 8 outlines the proposed inter-device (D2D) discovery method from the perspective of a User Equipment (UE) in an exemplary embodiment according to the invention. In step S901, the UE initiates a D2D discovery procedure and has a window value, wherein the window value represents a time window and is a positive number. In step S902, the UE transmits a first proximity discovery request including at least the window value. In step S903, the UE detects a cancellation event (cancellation event) to cancel the D2D discovery process in response to the transmitted first proximity discovery request. The cancellation event may come from a hardware trigger initiated by a hardware component of the UE or a software trigger generated by, for example, an application layer of the UE. In step S904, in response to the detected cancellation event, if the window value decreases to a certain threshold, the UE stops the D2D discovery procedure. In step S905, if there is no other proximity discovery request within the UE, the UE transmits a cancel proximity discovery request to cancel the D2D discovery procedure in response to the received cancel event.

The first proximity discovery request may be transmitted to a network entity within an Evolved Packet Core (EPC) network. The transmitting a cancel proximity discovery request may include transmitting a cancel proximity discovery request as an explicit request and having parameters not limited to a network level Identifier (ID), a server ID, an application layer discoverer ID, and/or an application layer discoverer ID. The transmitting a cancel proximity discovery request may include transmitting a second cancel proximity discovery request having parameters of a window value, a network level ID, a server ID, an application layer discoverer ID, a range class, and discoverer location information, without limitation, of a predetermined value. The aforementioned window value may, for example, be set to zero. The parameter of the second cancel proximity discovery request may further include a Wireless Local Area Network (WLAN) link layer ID.

The method of fig. 8 may also include waiting for a detect (detect) proximity response from a network entity and receiving a third cancel proximity discovery request with parameters including a UE cause status (cause) from a network entity within an Evolved Packet Core (EPC) network in response to the detected cancel event.

Fig. 9 outlines the proposed inter-device (D2D) discovery method from the perspective of a network entity according to one of the exemplary embodiments of the invention. In step S1001, the network entity receives a proximity discovery request for performing a network assisted D2D discovery procedure, the proximity discovery request including at least one window value. In step S1002, the network entity performs proximity estimation and User Equipment (UE) state estimation in response to the received proximity discovery request. In step S1003, the network entity cancels the network assisted D2D discovery procedure based on the result of performing the proximity estimation and the UE status estimation in step S1002. Based on the network entity canceling the network assisted D2D discovery procedure in step S1003, the network entity cancels the proximity discovery request by transmitting in step S1004a and cancels the location report request by transmitting in step S1004 b.

The method of fig. 9 may further include receiving a second proximity discovery request including a second window value set to zero or a value less than the initial window value, and canceling the network assisted D2D discovery process. The network entity may be a ProSe function within an Evolved Packet Core (EPC) and operate in accordance with a version of the third generation partnership project (3GPP) specification. The aforementioned performing proximity estimation and User Equipment (UE) state estimation may include: obtaining first proximity information of a discoverer (discoverer); obtaining second proximity information of a discoveree (discoveree); and determining whether the finder and the finder are adjacent or estimated to be adjacent within the window value period based on the first proximity information and the second proximity information.

The method of fig. 9 may further include obtaining UE status of the discoveree, e.g., idle status, active status, and status separate from the network, and determining whether to cancel the network assisted D2D discovery process based on the discoveree's status. The obtaining the UE status of the discoveree may include transmitting a status request to a Mobility Management Entity (MME), wherein the status request includes a discoveree ID; and receiving a status response from the MME indicating the UE status of the discoveree. The method of fig. 9 may further include receiving a cancel proximity request having parameters including a network level Identifier (ID), a server ID, an application layer discoverer ID, and an application layer discoverer ID.

Fig. 10 is an exemplary UE according to the present invention. The UE contains, but is not limited to, processing circuitry 1101 coupled to an analog-to-digital (a/D) converter/digital-to-analog (D/a) converter 1102, a transmitter 1103, a receiver 1104, and one or more antenna units 1105. The transmitter 1103 and the receiver 1104 wirelessly transmit a downlink signal and receive an uplink signal. The transmitter 1103 and receiver 1104 may also perform operations such as low noise amplification, impedance matching, mixing, up or down conversion, filtering, amplification, and so on. The (a/D)/(D/a) converter 1102 is configured to convert from an analog signal format to a digital signal format during uplink signal processing and from a digital signal format to an analog signal format during downlink signal processing. The processing circuit 1101 is configured to process the digital signal and execute the procedure of the D2D discovery method proposed according to the foregoing exemplary embodiments of the present invention (in particular fig. 3-6 and 8 and their corresponding written descriptions). Also, the processing circuit 1101 may optionally be coupled to a non-transitory storage medium to store programming code, device configurations, codebooks (codebooks), buffered or persistent data, and the like. The functions of the processing circuit 1101 may be implemented using programmable units such as microprocessors, microcontrollers, DSP chips, FPGAs, etc. The functions of the processing circuit 1101 may also be implemented in a stand-alone electronic device or IC, and the functions performed by the processing circuit 1101 may be implemented within a network of hardware or software.

Fig. 11 is an exemplary network entity according to the present invention. Exemplary network entities may be ProSe functions within the EPC core and include at least, but are not limited to: processing circuitry 1201 which is coupled to communication protocol circuitry 1202, and the communication protocol circuitry 1202 is coupled to a transmitter 1203 and a receiver 1204. The transmitter 1203 and the receiver 1203 are used to transmit and receive modulated signals, which may be wireless RF signals, optical signals, or signals sent over cables. The communication protocol circuit 1202 may be independent of the processing circuit 1201 or be an inherent part of the processing circuit 1201 and convert digital messages into a format compatible with various interfaces, such as PC2, PC3, PC4, PC4x, and the like. The processing circuit 1201 is configured to process the digital signal and execute the procedure of the proposed D2D discovery method according to the aforementioned exemplary embodiments of the invention (in particular fig. 4-7 and 9 and their corresponding written descriptions). Also, the processing circuit 1201 may be optionally coupled to a non-transitory storage medium to store programming code, device configurations, codebooks, buffered or permanent data, and so forth. The functions of the processing circuit 1201 may be implemented using programmable units such as microprocessors, microcontrollers, DSP chips, FPGAs, etc. The functions of the processing circuit 1201 may also be implemented in a stand-alone electronic device or IC, and the functions performed by the processing circuit 1201 may also be implemented within a network of hardware or software.

In view of the foregoing, the present invention is applicable to a wireless communication system and is capable of dynamically stopping a ProSe discovery procedure based on the needs and network conditions of ProSe applications and user preferences and settings. By minimizing network signaling related to proximity determination and avoiding unnecessary computational power related to location updates and proximity estimation, the load on the network may be reduced and the efficiency of the network may be increased.

No element, act, or instruction used in the detailed description of the disclosed embodiments of the present application should be construed as critical or essential to the invention unless explicitly described as such. Also, as used herein, the word "a" may also include more than one item. If only one item is intended, the term "single" or similar language will be used. Further, as used herein, the term "any of" preceding a list of a plurality of items and/or a plurality of categories of items is intended to encompass any of the items and/or categories of items, "any combination of," any plurality of, "and/or any combination of a plurality of" either individually or in combination with other items and/or other categories of items. Further, as used herein, the term "set" is intended to encompass any number of items, including zero. Furthermore, as used herein, the term "amount" is intended to encompass any amount, including zero.

It will be understood by those skilled in the art that various modifications and changes in the structure of the disclosed embodiments may be made without departing from the scope or spirit of the invention. In view of the above, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority from united states provisional application No. 61/926,927, filed on day 1, 13, 2014, united states application No. 14/578,505, filed on day 12, 22, 2014, and taiwan application No. 103145941, filed on day 12, 27, 2014. The entire contents of the above-mentioned patent application are hereby incorporated by reference herein and form a part of this specification.

Claims

1. A network entity, comprising:

a transmitter for transmitting data;

a receiver for receiving data;

a processing circuit coupled to the transmitter and the receiver and configured to:

receiving, via the receiver, a first cancel proximity request comprising a network level discoverer identifier, an application identifier and an application level discoverer identifier;

transmitting, via the transmitter, a second cancel proximity request including the network level discoverer identifier and a network level discoverer identifier in response to the received first cancel proximity request;

receiving, via the receiver, a first acknowledgement signal corresponding to the second cancel proximity request in response to the transmitted second cancel proximity request;

and transmitting, via the transmitter, a second acknowledgement signal corresponding to the first cancel proximity request in response to the received first acknowledgement signal.

2. An inter-device discovery method for a network entity, comprising:

receiving a first cancel proximity request comprising a network level discoverer identifier, an application identifier and an application level discoverer identifier;

transmitting a second cancel proximity request including the network level discoverer identifier and a network level discoverer identifier in response to the received first cancel proximity request;

receiving a first acknowledgement signal corresponding to the second cancel proximity request in response to the transmitted second cancel proximity request; and

transmitting a second acknowledgement signal corresponding to the first cancel proximity request in response to the received first acknowledgement signal.

3. The method for inter-device discovery applicable to a network entity of claim 2, further comprising:

transmitting a first cancel location report signal after transmitting the second cancel proximity request.

4. The method for inter-device discovery applicable to a network entity of claim 3, further comprising:

transmitting a second cancel position report signal after transmitting the first cancel position report signal.

5. The method of claim 2, wherein the network entity is a network entity with proximity services functionality within an evolved packet core network.

6. The inter-device discovery method for a network entity of claim 3, wherein receiving the first cancel proximity request comprises receiving the first cancel proximity request from a user equipment.

7. The inter-device discovery method for a network entity of claim 6, wherein said first cancel location report signal cancels a location report of said user equipment.

8. The inter-device discovery method for a network entity of claim 2, wherein transmitting the second cancel proximity request comprises transmitting the second cancel proximity request to another proximity services enabled network entity within an evolved packet core network.

9. The inter-device discovery method for a network entity of claim 8, wherein receiving the first acknowledgement signal comprises receiving the first acknowledgement signal from the other proximity services enabled network entity within the evolved packet core network.

10. The inter-device discovery method for a network entity of claim 6, wherein transmitting said second acknowledgement signal comprises transmitting said second acknowledgement signal to said user equipment.