CN106162676A

CN106162676A - A kind of equipment direct communication system relay state determines method and device

Info

Publication number: CN106162676A
Application number: CN201510134755.5A
Authority: CN
Inventors: 陈琳; 李大鹏; 黄莹; 罗薇
Original assignee: ZTE Corp
Current assignee: ZTE Corp
Priority date: 2015-03-25
Filing date: 2015-03-25
Publication date: 2016-11-23
Also published as: WO2016150107A1

Abstract

The invention discloses a kind of equipment direct communication system relay state and determine method and apparatus.Described method includes: trunk subscriber equipment UE obtains link deployment information and/or receives device-to-device D2D information, determines the relay state of relaying UE according to described link deployment information and/or D2D information.Described device is positioned at trunk subscriber equipment UE, including data obtaining module and state determining module.The method and apparatus being proposed by the embodiment of the present invention, the UE possessing relay capabilities can enter relaying the second state when not having remote subscriber to access, enter first state of relaying when receiving after remote subscriber finds the request relaying, periodic broadcast relay information, realize the switching of relaying UE relay state in this way, the purpose of economize on electricity can be reached when relaying UE and being in relaying the second state.

Description

Method and device for determining relay state of equipment direct connection system

Technical Field

The invention relates to the technical field of wireless communication, in particular to a method and a device for determining a relay state of a device direct connection system.

Background

With the development of wireless multimedia services, the demand for high data rate and user experience is increasing, and thus higher requirements are placed on the system capacity and coverage of the conventional cellular network. On the other hand, application scenarios such as public safety, social networking, close-range data sharing, local advertising and the like have increased the need for people to know and communicate with people or things nearby. Given the significant limitations of conventional base station-centric cellular networks in terms of high data rates and support for proximity services, D2D (Device-to-Device or Device-through) technology, which represents a new direction in future communication technology development, has come into force. The application of the D2D technology can reduce the burden of the cellular network, reduce the battery power consumption of the user equipment, increase the data rate, and improve the robustness of the network infrastructure, and well meet the requirements of the high data rate service and the proximity service. The D2D technology is also called Proximity Services (ProSe), single edge link (SL).

The D2D technology may operate in licensed or unlicensed bands, allowing multiple D2D capable User Equipment (i.e., D2D User Equipment, D2D User Equipment, D2D UE) to perform direct discovery and/or direct communication with or without network infrastructure. There are three main application scenarios of D2D:

1) the UE1 and the UE2 perform data interaction under the coverage of a cellular network, and the user plane data does not pass through the network infrastructure, as in scenario 1 of fig. 1;

2) in the UE relay transmission in the weak coverage area or the no coverage area, as in scenario 2 in fig. 1, the UE4 with poor signal quality is allowed to communicate with the network through the UE3 with nearby network coverage, which can help the operator to expand coverage and improve capacity;

3) in the event of an earthquake or an emergency, the cellular network cannot work normally, and direct communication among devices is allowed, such as scenario 3, UE5, control plane and user plane between UE6 and UE7 in fig. 1, and one-hop or multi-hop data communication is performed without passing through the network infrastructure.

The D2D technology generally includes D2D discovery technology and D2D communication technology, wherein the D2D discovery technology refers to technology for determining or determining whether a first user equipment is proximate to a second user equipment. Generally, D2D user devices can discover each other by sending or receiving discovery signals (discovery information); the D2D communication technology refers to a technology in which some or all of communication data between D2D user devices may be communicated directly without passing through a network infrastructure.

For a UE-to-Network Relay (UE-to-Network Relay) scenario corresponding to scenario 2 in fig. 1, the UE3 may communicate with the Network side using an existing LTE scheme, and may also communicate with a terminal (UE 4 in the figure) outside the coverage (out of coverage) using a D2D scheme as a Relay, where the schemes include D2D Discovery (Discovery) and/or D2D communication (communication). If an out-of-coverage or poorly signal terminal UE4 transmits data to the base station through an in-coverage terminal UE3, we call UE4 as a Remote user (Remote UE) and UE3 as a Relay user (Relay UE). Similarly, for the UE-to-UE Relay scenario corresponding to scenario 3, the UE6 may forward the data packet between the UE5 and the UE7, and then the UE6 may be referred to as a Relay user, and the UE5 and the UE7 may be referred to as a far-end user.

The prior art does not provide a solution for system perfection for the relay state mechanism of the relay transmission mode of scene 2 and scene 3.

Disclosure of Invention

The invention aims to provide a method and a device for determining a relay state of a device direct connection system.

In order to solve the above technical problem, the present invention provides a method for determining a relay state of a device-through system, including:

the relay User Equipment (UE) acquires relay configuration information and/or receiving equipment-to-equipment (D2D) information, and determines the relay state of the relay UE according to the relay configuration information and/or the D2D information.

Further, the relay UE acquiring relay configuration information includes:

the relay UE receives relay configuration information sent by a base station or a short-distance service function, or the relay UE acquires the relay configuration information pre-configured by the relay UE;

the relay configuration information includes at least one of: relay discovery resource or resource pool information, relay communication resource or resource pool information, an activation indication of a relay function, a deactivation indication of a relay function, a relay power saving enable indication, a relay power saving disable indication, a relay activity status timer, a remote UE activity status timer.

Further, the relay discovery resource or resource pool information includes: a relay discovery transmitting resource or resource pool, a relay discovery receiving resource pool; the relay communication resource or resource pool information includes: the relay communication sending resource or resource pool, and the relay communication receiving resource pool.

Further, the relay discovery transmission resource or resource pool comprises at least one of: D2D discovery with coverage sends resources or resource pools, D2D discovery without coverage sends resource pools; the relay discovery reception resource pool includes: coverage D2D discovery receive resource pool, and non-coverage D2D discovery receive resource pool; wherein: the covered D2D discovery receiving resource pool includes a D2D discovery transmitting resource pool of the relay UE serving cell and a D2D discovery transmitting resource pool corresponding to a neighboring cell of the relay UE serving cell.

Further, the relay configuration information further includes one or more of the following: relaying the first state listening period, listening frame offset, listening subframe offset, listening duration.

Further, the determining, by the relay UE, the relay state of the relay UE according to the relay configuration information includes:

the relay configuration information includes: a relay function activation indication, the relay UE performing a relay function; or

The relay configuration information includes: a relay function deactivation indication that the relay UE is no longer performing a relay function; or

The relay configuration information includes: a relay power saving enable indication, the relay UE enters a relay first state according to the relay configuration information; or

The relay configuration information includes: and a relay power saving prohibition instruction, wherein the relay UE enters a relay second state according to the relay configuration information.

Further, the determining, by the relay UE, the relay status of the relay UE according to the relay configuration information and/or the D2D information includes:

the relay UE enters a relay second state after receiving D2D information for discovering a relay, which is sent by the remote UE; or,

and after receiving the D2D information for discovering the relay sent by the remote UE, the relay UE interacts with the remote UE and enters a relay second state after establishing connection with the remote UE.

Further, after receiving the relay discovery D2D information sent by the remote UE, the relay UE interacts with the remote UE, and enters a relay second state after establishing a connection with the remote UE, where the relay UE includes:

the relay UE sends a relay discovery response D2D message to the remote UE after receiving the relay discovery D2D message sent by the remote UE, and sends a relay connection establishment message to the remote UE after receiving a relay connection establishment request sent by the remote UE, and the relay UE enters a relay second state.

Further, the determining, by the relay UE, the relay state of the relay UE according to the relay configuration information and the D2D information includes:

and the relay UE starts the relay activity state timer when entering a relay second state, and enters a relay first state when the relay activity state timer is overtime.

Further, after the relay UE starts the relay activity status timer, the method further includes:

the relay UE restarts the relay active state timer upon any of the following events:

receiving D2D communication information sent by any accessed remote UE to the relay UE; receiving D2D discovery information sent by any accessed remote UE; and the relay UE sends D2D communication information to any accessed remote UE.

when the relay UE is accessed to the remote UE, setting and starting a corresponding active state timer for the remote UE;

when the active state timer of the remote UE is overtime, the relay UE releases the connection with the remote UE; or when the active state timer of the remote UE is overtime, the relay UE sends D2D information or paging information for discovering the remote UE to the remote UE, and if response information sent by the remote UE is not received within a predetermined time, the relay UE releases the connection with the remote UE;

when the relay UE receives connection release request information sent by the accessed remote UE, stopping an active state timer corresponding to the remote UE and releasing the connection with the remote UE;

and the relay UE enters a relay first state after releasing the connection of all the accessed remote UE.

Further, after the relay UE sets and starts a corresponding active state timer for the remote UE, the method further includes:

when any one of the following events occurs, the relay UE restarts an active state timer corresponding to the remote UE:

receiving D2D communication information sent by the remote UE to the relay UE; receiving D2D discovery information sent by the remote UE; the relay UE sends D2D communication information to the remote UE.

Further, it is determined that the relay status of the relay UE is a relay first status, and the method further includes: the relay UE in the relay first state performs one of the following operations:

receiving D2D information for discovering the relay sent by the remote UE;

and D2D information for discovering the relay sent by the remote UE is received, the information interacts with the remote UE, and the connection is established with the remote UE.

Further, it is determined that the relay status of the relay UE is a relay second status, and the method further includes: the relay UE in the relay second state performs one or more of the following operations:

periodically sending relay broadcast information;

receiving D2D information for discovering the relay sent by a remote UE which has not accessed the relay UE;

receiving D2D discovery information transmitted by a remote UE having access to the relay UE;

receiving D2D communication information sent by a remote UE which has access to the relay UE;

and sending D2D communication information to the remote UE which has access to the relay UE.

Further, the method further comprises: and after receiving the relay broadcast information sent by the relay UE in the relay second state, the remote UE which is not accessed to the relay UE selects one relay UE and sends a relay connection establishment request to the selected relay UE, and after receiving the relay connection establishment request, the relay UE sends the relay connection establishment information to the remote UE.

Further, after the relay UE determines the relay status of the relay UE, the method further includes: and the relay UE reports the relay state of the relay UE to the base station.

In order to solve the above technical problem, the present invention further provides a device for determining a relay state of a device-through system, which is located in a relay user equipment UE, and includes an information obtaining module and a state determining module, wherein:

the information acquisition module is used for acquiring relay configuration information and/or receiving device-to-device D2D information;

the state determining module is configured to determine a relay state of the relay UE according to the relay configuration information and/or the D2D information.

Further, the acquiring relay configuration information by the information acquiring module includes:

the information acquisition module receives relay configuration information sent by a base station or a short-range service function, or the information acquisition module acquires the relay configuration information preconfigured by the relay UE.

Further, the determining the relay status of the relay UE according to the relay configuration information includes:

Further, the determining the relay status of the relay UE according to the relay configuration information and/or the D2D information includes:

the state determining module determines that the relay UE enters a relay second state after receiving D2D information for discovering a relay, which is sent by remote UE; or,

the state determination module interacts with the remote UE after receiving the relay discovery D2D information sent by the remote UE, and determines that the relay UE enters a relay second state after the relay UE establishes a connection with the remote UE.

Further, after receiving the relay discovery D2D information sent by the remote UE, the state determination module interacts with the remote UE, and after the relay UE establishes a connection with the remote UE, determines that the relay UE enters a relay second state, including:

the state determination module sends relay discovery response D2D information to the remote UE after receiving relay discovery D2D information sent by the remote UE, and sends relay connection establishment information to the remote UE after receiving a relay connection establishment request sent by the remote UE, and determines that the relay UE enters a relay second state.

Further, the determining the relay status of the relay UE according to the relay configuration information and the D2D information includes:

the state determining module starts the relay activity state timer when the relay UE enters a relay second state, and determines that the relay UE enters a relay first state when the relay activity state timer is overtime.

Further, after the relay activity state timer is started, the state determination module is further configured to determine that any one of the following events occurs, and restart the relay activity state timer:

the state determining module sets and starts a corresponding active state timer for the remote UE when the remote UE accesses the relay UE; when the active state timer of the remote UE is overtime, informing the relay UE to release the connection with the remote UE; or when the active state timer of the remote UE is overtime, the state determination module sends D2D information or paging information for finding the remote UE to the remote UE, and if response information sent by the remote UE is not received within a predetermined time, the relay UE is notified to release the connection with the remote UE; when the state determining module receives connection release request information sent by the accessed remote UE, the state determining module stops an active state timer corresponding to the remote UE and informs the relay UE to release the connection with the remote UE; and after the relay UE releases the connection of all the accessed remote UEs, the state determining module determines that the relay UE enters a relay first state.

Further, the state determining module is further configured to, after setting and starting a corresponding active state timer for the remote UE, determine that any one of the following events occurs, and restart the active state timer corresponding to the remote UE:

Further, the status determining module determines that the relay status of the relay UE is a relay first status, and the apparatus further includes a first module configured to perform one of the following operations:

receiving D2D information for discovering the relay sent by the remote UE;

Further, the status determining module determines that the relay status of the relay UE is a relay second status, and the apparatus further includes a second module configured to perform one or more of the following operations:

periodically sending relay broadcast information;

Further, the second module is further configured to: and after receiving a relay connection establishment request sent by a remote UE which is not accessed to the relay UE, sending relay connection establishment information to the remote UE.

Further, the apparatus further includes a reporting module, configured to report the relay status of the relay UE to a base station after the status determining module determines the relay status of the relay UE.

By the method and the device provided by the embodiment of the invention, the UE with the relay capability can enter the relay second state when no remote user accesses, and enter the relay first state after receiving the request of the remote user for searching the relay, and periodically broadcast the relay information.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

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, illustrate embodiments of the invention and together with the example serve to explain the principles of the invention and not to limit the invention.

Fig. 1 is a schematic diagram of device-through system discovery/communication;

fig. 2 is a schematic diagram of a method for determining a relay state in a device-through system according to embodiment 1 of the present invention;

fig. 3 is a schematic diagram of a device-to-device system relay state determination apparatus according to embodiment 2 of the present invention;

FIG. 4 is a diagram illustrating the relay state transition of the device-through system of the present invention;

fig. 5 is a flow chart of an application example 1 base station configuration relay node enabling power saving;

fig. 6 is a flow chart of an application example 2 base station configuring a relay node to enable power saving;

fig. 7 is a flow diagram of an application example 3 relay UE entering a relay active state from a relay inactive state;

fig. 8 is a flow diagram of an application example 4 relay UE entering a relay active state from a relay inactive state;

fig. 9 is a remote UE relay activity status maintenance flow diagram applying example 5;

fig. 10 is a flow diagram of an application example 6 relay UE from a relay active state to a relay inactive state;

fig. 11 is a flow diagram of an application example 7 relay UE from a relay active state to a relay inactive state;

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be noted that the embodiments and features of the embodiments in the present application may be arbitrarily combined with each other without conflict.

The steps illustrated in the flow charts of the figures may be performed in a computer system such as a set of computer-executable instructions. Also, while a logical order is shown in the flow diagrams, in some cases, the steps shown or described may be performed in an order different than here.

Example 1

The present embodiment describes a method for determining a relay status of a device-through system, as shown in fig. 2, including:

step 10, the relay UE acquires relay configuration information and/or receiving device-to-device D2D information;

the method comprises the steps that relay UE receives relay configuration information sent by a base station or a short-distance service function (ProSe function) entity, or the relay UE acquires the relay configuration information pre-configured by the relay UE;

the relay configuration information includes at least one of: relay discovery resource or resource pool information, relay communication resource or resource pool information, an activation indication of a relay function, a deactivation indication of a relay function, a relay power saving enable indication, a relay power saving disable indication, a relay activity status timer, a remote UE activity status timer. Wherein the relay discovery resource or resource pool information includes: a relay discovery transmitting resource or resource pool, a relay discovery receiving resource pool; the relay communication resource or resource pool information includes: the relay communication sending resource or resource pool, and the relay communication receiving resource pool. The relay discovery transmission resource or resource pool comprises at least one of: D2D discovery with coverage sends resources or resource pools, D2D discovery without coverage sends resource pools; the relay discovery reception resource pool includes: coverage D2D discovery receive resource pool, and non-coverage D2D discovery receive resource pool; wherein: the covered D2D discovery receiving resource pool includes a D2D discovery transmitting resource pool of the relay UE serving cell and a D2D discovery transmitting resource pool corresponding to a neighboring cell of the relay UE serving cell.

Preferably, the relay configuration information further comprises one or more of the following: relaying the first state listening period, listening frame offset, listening subframe offset, listening duration.

And step 20, determining the relay state of the relay UE according to the relay configuration information and/or the D2D information.

Preferably, after the UE starts the relay function and/or determines the relay status of the relay UE according to the self-preconfigured information, the relay UE reports the UE executing the relay function and/or the relay status of the relay UE to the base station.

● use 1:

the application is to determine the relay state of the relay UE according to the relay configuration information, and comprises the following conditions:

if the relay configuration information comprises a relay function activation indication, the relay UE executes a relay function;

if the relay configuration information comprises a relay function deactivation indication, the relay UE does not execute the relay function;

if the relay configuration information comprises a relay power saving enabling indication, the relay UE executing the relay function enters a relay first state according to the relay configuration information;

and if the relay configuration information comprises a relay power saving prohibition indication, the relay UE executing the relay function enters a relay second state according to the relay configuration information.

The relay function activation and deactivation indication in the relay configuration information may be indicated in a displayed or implicit manner. If the relay function is activated by an explicit indication through an IE field or a MAC CE in an RRC message or by the UE acquiring the relay configuration information, i.e., by an implicit indication, the relay function is implicitly activated if the reconfiguration information received by the UE does not include the relay configuration information any more.

● use 2:

the application is an application that the relay UE enters the relay second state from the relay first state according to the relay configuration information and/or the D2D information, and the application comprises one of the following conditions:

in case one, the relay UE directly enters a relay second state after receiving the relay discovery D2D information sent by the remote UE;

in case two, after receiving the relay discovery D2D information sent by the remote UE, the relay UE interacts with the remote UE, and enters a relay second state after establishing a connection with the remote UE.

Specifically, after receiving the relay discovery D2D information sent by the remote UE, the relay UE sends a relay discovery response D2D information to the remote UE, and after receiving a relay connection establishment request sent by the remote UE, sends relay connection establishment information to the remote UE, and the relay UE enters a relay second state.

● application 3:

the application is an application that the relay UE enters the relay first state from the relay second state according to the relay configuration information and the D2D information, and comprises one of the following conditions:

in case one, the relay UE starts the relay active state timer when entering the relay second state, and when the relay active state timer is overtime, the relay UE enters the relay first state.

Preferably, after the relay UE starts the relay active state timer, the relay UE restarts the relay active state timer when any one of the following events occurs: receiving D2D communication information sent by any accessed remote UE to the relay UE; receiving D2D discovery information sent by any accessed remote UE; and the relay UE sends D2D communication information to any accessed remote UE.

In case two, when the relay UE is accessed to the remote UE, setting and starting a corresponding active state timer for the remote UE; when the active state timer of the remote UE is overtime, the relay UE releases the connection with the remote UE; the relay UE can also send D2D information or paging information for finding the remote UE to the remote UE when the active state timer of the remote UE is timed out, and if the response information sent by the remote UE cannot be received within preset time, the relay UE releases the connection with the remote UE; when the relay UE receives connection release request information sent by the accessed remote UE, stopping an active state timer corresponding to the remote UE and releasing the connection with the remote UE; and the relay UE enters a relay first state after releasing the connection of all the accessed remote UE.

Preferably, after the relay UE sets and starts a corresponding active state timer for the remote UE, the relay UE restarts the active state timer corresponding to the remote UE when any one of the following events occurs: receiving D2D communication information sent by the remote UE to the relay UE; receiving D2D discovery information sent by the remote UE; the relay UE sends D2D communication information to the remote UE.

From another perspective, the relay UE in the relay first state performs one of the following operations:

(1) receiving D2D information for discovering the relay sent by the remote UE;

(2) and D2D information for discovering the relay sent by the remote UE is received, the information interacts with the remote UE, and the connection is established with the remote UE.

Specifically, after receiving the relay discovery D2D information sent by a remote UE, sending relay discovery response D2D information to the remote UE; and after receiving a relay connection establishment request sent by the remote UE, sending relay connection establishment information to the remote UE.

The relay UE in the relay second state performs one or more of the following operations:

(1) periodically sending relay broadcast information;

and after receiving the relay broadcast information sent by the relay UE in the relay second state, the remote UE which is not accessed to the relay UE selects one relay UE and sends a relay connection establishment request to the selected relay UE, and after receiving the relay connection establishment request, the relay UE sends the relay connection establishment information to the remote UE.

(2) Receiving D2D information for discovering the relay sent by a remote UE which has not accessed the relay UE;

(3) receiving D2D discovery information transmitted by a remote UE having access to the relay UE;

(4) receiving D2D communication information sent to the relay UE by a remote UE which has access to the relay UE;

(5) and sending D2D communication information to the remote UE which has access to the relay UE.

Example 2

This embodiment describes an apparatus for determining a relay status of a device-through system, where the apparatus is located in a relay user equipment UE, as shown in fig. 3, and includes an information obtaining module and a status determining module, where:

specifically, the information acquisition module receives relay configuration information sent by a base station or a ProSe function, or the information acquisition module acquires relay configuration information preconfigured by the relay UE;

● application 1

The state determining module determines the relay state of the relay UE according to the relay configuration information, and the method comprises the following conditions:

● use 2:

the state determination module determines that the relay UE enters a relay second state from a relay first state according to the relay configuration information and/or the D2D information:

in case one, the state determination module determines that the relay UE enters a relay second state after receiving relay discovery D2D information sent by a remote UE;

in case two, the state determination module interacts with the remote UE after receiving the relay discovery D2D information sent by the remote UE, and determines that the relay UE enters the relay second state after establishing a connection with the remote UE.

Specifically, the state determination module sends a relay discovery response D2D message to the remote UE after receiving a relay discovery D2D message sent by the remote UE, and sends a relay connection establishment message to the remote UE after receiving a relay connection establishment request sent by the remote UE, to determine that the relay UE enters the relay second state.

● application 3:

the state determination module determines that the relay UE enters the relay first state from the relay second state according to the relay configuration information and the D2D information:

in case one, the state determining module starts the relay active state timer when the relay UE enters the relay second state, and determines that the relay UE enters the relay first state when the relay active state timer is overtime.

Preferably, after the relay activity status timer is started, the status determining module is further configured to restart the relay activity status timer if any one of the following events occurs: receiving D2D communication information sent by any accessed remote UE to the relay UE; receiving D2D discovery information sent by any accessed remote UE; and the relay UE sends D2D communication information to any accessed remote UE.

In case two, the state determining module sets and starts a corresponding active state timer for the remote UE when the remote UE accesses the relay UE; when the active state timer of the remote UE is overtime, informing the relay UE to release the connection with the remote UE; the relay UE can also send D2D information or paging information for finding the remote UE to the remote UE when the active state timer of the remote UE is timed out, and if the response information sent by the remote UE cannot be received within preset time, the relay UE releases the connection with the remote UE; when the state determining module receives connection release request information sent by the accessed remote UE, the state determining module stops an active state timer corresponding to the remote UE and informs the relay UE to release the connection with the remote UE; and after the relay UE releases the connection of all the accessed remote UEs, the state determining module determines that the relay UE enters a relay first state.

Preferably, the state determining module is further configured to, after setting and starting a corresponding active state timer for the remote UE, determine that any one of the following events occurs, and restart the active state timer corresponding to the remote UE: receiving D2D communication information sent by the remote UE to the relay UE; receiving D2D discovery information sent by the remote UE; the relay UE sends D2D communication information to the remote UE.

In a preferred embodiment, the status determining module determines that the relay status of the relay UE is a relay first status, and the apparatus further includes a first module configured to perform one of the following operations:

(1) receiving D2D information for discovering the relay sent by the remote UE;

Specifically, the first module sends discovery relay response D2D information to a remote UE after receiving the discovery relay D2D information sent by the remote UE; and the first module sends relay connection establishment information to the remote UE after receiving the relay connection establishment request sent by the remote UE.

In a preferred embodiment, the status determining module determines that the relay status of the relay UE is a relay second status, and the apparatus further includes a second module configured to perform one or more of the following operations:

(1) periodically sending relay broadcast information;

(4) receiving D2D communication information sent by a remote UE which has access to the relay UE;

Preferably, the second module is further configured to: and after receiving a relay connection establishment request sent by a remote UE which is not accessed to the relay UE, sending relay connection establishment information to the remote UE.

In a preferred embodiment, the apparatus further includes a reporting module, configured to report the relay status of the relay UE to a base station after the status determining module determines the relay status of the relay UE.

The method of the above embodiment is further described below with reference to application examples. Hereinafter, the relay first state is referred to as a relay inactive state, and the relay second state is referred to as a relay active state.

The UE with the relay capability can enter an inactive state when no remote user accesses, and enter a relay active state after receiving D2D information for finding a relay sent by the remote user, so that relay information is periodically broadcast, and the aim of saving power of the relay UE can be fulfilled.

The relay UE may be in two states: a relay active state and a relay inactive state. As shown in fig. 4, when there is no remote UE around, the relay UE enters a relay inactive state, in which the relay UE only periodically wakes up to listen on the relay discovery reception resource for the D2D information (e.g., find relay request message) of discovery relay sent by the remote UE, and if so, the relay UE sends a discovery relay response D2D information to the remote UE. And then the relay UE waits for a connection establishment request sent by the remote UE, and if the relay UE receives the connection establishment request, the relay UE sends a connection establishment message to the remote UE so as to establish connection with the remote UE. Meanwhile, the relay UE enters a relay active state. In addition, the relay UE may also enter the relay active state immediately after receiving the D2D information that the remote UE sends to discover the relay.

After the relay UE enters the relay active state, the relay UE can transmit the relay information in a periodic broadcast mode while forwarding the data packet of the remote UE, and access is performed after more remote UEs hear the information. The relay UE may maintain a relay active state timer, restart the timer when the relay UE forwards a data packet for the remote UE, or receives an access request sent by the remote UE or D2D discovery information sent by the remote UE that has accessed the relay UE, and if the timer expires, the relay UE considers that the accessed remote UE is in an inactive state, so the relay UE may initiate to release a connection with the remote UE and enter the relay inactive state. In addition, the relay UE may set an active status timer for each accessed remote UE, and restart the active status timer corresponding to the remote UE whenever receiving a data packet or a discovery message from the remote UE or transmitting a data packet to the remote UE. And when the active state timer corresponding to the remote UE is overtime, the relay UE releases the context of the remote UE which is locally stored. The relay UE may further send D2D information or paging information for discovering the remote UE to the remote UE when an active state timer of the remote UE expires, and if response information sent by the remote UE is not received within a predetermined time, the relay UE releases the connection with the remote UE. In addition, the relay UE may also receive connection release information sent by the remote UE, and when receiving the connection release information, the relay UE resets an active state timer corresponding to the remote UE and releases the context of the remote UE. In addition, when a high-Priority remote UE or a bearer request of a higher ARP (Allocation and reservation Priority) is established, the relay UE may actively send a message to the low-Priority remote UE that can preempt resources to request to release the connection. When the relay UE releases the PC5 connections of all the remote UEs, the relay UE returns to the relay inactive state, and does not periodically send the relay message and listen to the relay data receiving resource any more, and at this time, only periodically listens to whether there is the relay discovery D2D information sent by the remote UE.

Specific possible relay power saving methods and related signaling flows are given below by way of application examples.

Application example 1

Officer a, B use D2D capable UE1 and UE2, respectively. UE1 is in a network covered state, while UE2 is in no network covered state. This example describes a flow of a base station configuring a relay node to enable power saving. The UE1 with network coverage is interested in becoming a relay node and providing relay service for the UE without coverage, for example, the UE1 is interested in becoming a UE-to-network relay. As shown in fig. 5, the method comprises the following steps:

step 1, the UE1 may send D2D relay information to the base station, which includes interest indication of relay and current location information of the UE;

step 2, the base station receives the D2D relay information sent by the UE1 and selects the UE1 as the relay node, and then the base station sends relay configuration information, in this example, UE-to-network relay configuration establishment information, to the UE 1;

specifically, the relay configuration information may include one or more of the following information: relay discovery resource or resource pool information, relay communication resource or resource pool information, an activation indication of a relay function, a deactivation indication of a relay function, a relay power saving enable indication, a relay power saving disable indication, a relay activity status timer, a remote UE activity status timer, and the like. In this example, the relay configuration information includes at least an indication of activation of the relay function and an indication of relay power saving enable.

The relay communication resource or resource pool information is used for communication between the relay UE and the remote UE, and includes relay communication transmission resource or resource pool information and relay communication reception resource pool information. The relay discovery resource or resource pool information is used for the relay UE to discover the remote UE, and includes relay discovery transmission resource or resource pool information and relay discovery reception resource pool information. Further, the relay discovery transmission resource or resource pool information includes coverage D2D discovery transmission resource or resource pool information, and/or the non-coverage D2D discovery transmission resource pool information, and the relay discovery reception resource pool information includes coverage D2D discovery reception resource pool information and non-coverage D2D discovery reception resource pool information. The covered D2D discovery receiving resource pool information includes D2D discovery transmitting resources of the relay UE service or the resident cell and D2D discovery transmitting resources corresponding to the neighbor cell of the relay UE service or the resident cell.

In addition to the proprietary RRC (Radio Resource Control) signaling, the UE1 may also receive relay Resource pool configuration information from a base station broadcast message. In addition, the UE1 may also receive relay configuration information from a prose function (a network element entity for D2D configuration, authorization authentication, located in the core network) or the UE1 may pre-configure the relay configuration information.

Step 3, the UE1 receives the relay configuration information activating the relay function, then the UE1 starts the relay function, if the configuration information indicates relay power saving is enabled, then the UE1 enters the relay inactive state.

Application example 2

Mary, John and Peter hold UE1, UE2 and UE3, respectively, with D2D communication and relay functionality. UE1 and UE2 are within D2D communication range of each other, UE2 and UE3 are within D2D communication range of each other, and UE1 and UE3 are not within D2D communication range of each other. This example describes a flow for a base station to configure a relay node to enable power saving. Assuming that the base station configures the UE2 to be a UE-to-UE relay, as shown in fig. 6, the method includes the following steps:

step 1, the base station sends relay configuration information, in this example UE-to-UE relay configuration establishment information, to the UE 2;

specifically, the relay configuration information may include one or more of the following information: relay discovery resource or resource pool information, relay communication resource or resource pool information, an activation indication of a relay function, a deactivation indication of a relay function, a relay power saving enable indication, a relay power saving disable indication, a relay activity status timer, a remote UE activity status timer, and the like. In this example, the relay configuration information includes at least an activation instruction of the relay function and a relay power saving prohibition instruction.

The relay communication resource or resource pool information is used for communication between the relay UE and the remote UE, and includes relay communication transmission resource or resource pool information and relay communication reception resource pool information. The relay discovery resource or resource pool information is used for discovery of the relay UE and the remote UE, and includes relay discovery transmission resource or resource pool and relay discovery reception resource pool information. Further, the relay discovery transmission resource or resource pool information includes coverage D2D discovery transmission resource or resource pool information, and/or the non-coverage D2D discovery transmission resource pool information, and the relay discovery reception resource pool information includes coverage D2D discovery reception resource pool information and non-coverage D2D discovery reception resource pool information. The covered D2D discovery receiving resource pool information includes a D2D discovery transmitting resource pool of the relay UE serving cell (or called a camping cell) and a D2D discovery transmitting resource pool corresponding to a neighboring cell of the relay UE serving cell.

In addition to the proprietary RRC signaling, the UE2 may also receive relay resource pool configuration information from base station broadcast messages. In addition, the UE2 may also pre-configure relay configuration information from relay configuration information received from the ProSe function or UE 2.

Step 2, after the UE2 receives the relay configuration information, if the configuration information indicates to activate the relay function and prohibit relay power saving, the UE2 enters a relay active state.

Application example 3

Officer a, B use D2D capable UE1 and UE2, respectively. UE1 is in a network covered state, while UE2 is in no network covered state. This example describes a flow for a relay UE to enter a relay active state from a relay inactive state. The UE1 with network coverage is interested in becoming a relay node and providing relay service for the UE without coverage. Assuming that the base station selects UE1 as the relay node, as shown in fig. 7, the method includes the following steps:

step 1, the base station sends device-through relay configuration information to the UE1, after the UE1 receives the relay configuration information, if the configuration information indicates that the relay function is activated and relay power saving is enabled, the UE1 performs the relay function and enters a relay inactive state;

step 2, the relay UE1 monitors the D2D information sent by the remote UE to discover the relay on the relay discovery receiving resource pool;

the relay UE1 monitors the D2D discovery information sent by the remote UE on the relay discovery reception resource pool according to the relay inactive state monitoring period, the monitoring frame and/or subframe offset, the monitoring duration, and other information included in the relay configuration information. The UE1 need not listen to the corresponding subframe on the subframe corresponding to the non-relay discovery reception resource pool.

Step 3, the remote UE2 sends relay discovery D2D information;

at this time, if the remote UE2 in the no-coverage state wishes to find the relay UE connected to the network transmission information, the UE2 first monitors the relay discovery reception resource pool to determine whether there is D2D relay broadcast information sent by the relay UE nearby. If the relay broadcast information transmitted by the relay UE can be received, the remote UE2 selects one relay UE and transmits a relay connection establishment request to the selected relay UE. Assuming that the UE2 does not receive the relay broadcast information sent by the relay UE at this time, the remote UE2 sends D2D information to discover the relay.

The relay discovery D2D information sent by the remote UE2 may include some or all of the following: the relay discovery method comprises the steps of discovering a relay indication, identification and type of remote UE, relay type searched by the remote UE, communication target identification of the remote UE, communication group identification of the remote UE, priority of the remote UE and the like.

Step 4, the relay UE1 receives the D2D information sent by the remote UE2 to discover the relay, and determines that the UE2 is looking for the relay UE according to the message content, and then the UE1 enters a relay active state;

step 5, the relay UE1 transmits relay response D2D information to the remote UE2 using relay discovery transmission resources or randomly selecting resources from a relay discovery transmission resource pool;

the relay response D2D information may include some or all of the following: the relay mobile state indication method comprises a relay identification, a relay type, a relay service cell identification, a relay available time period, a relay group identification, a relay mobile state indication, relay PLMN information, a relay prohibition state indication and the like.

Step 6, when the UE2 receives the relay response D2D information sent by the relay UE1, the UE2 sends a relay connection establishment request to the relay UE1, and the relay UE1 receives the relay connection establishment request sent by the remote UE2, then the relay UE1 sends relay connection establishment information to the remote UE2, and the UE2 accesses the relay UE 1.

If the UE2 receives relay response D2D information transmitted by multiple relay UEs at the same time, the UE2 selects one relay UE and transmits a relay connection establishment request to the selected relay UE.

Upon access of the UE2 to the relay UE1, the relay UE1 may subsequently receive the D2D communication information transmitted by the UE2 on a relay communication reception resource pool, and transmit the D2D communication information to the remote UE2 using the relay communication transmission resource or randomly selecting a resource from the relay communication transmission resource pool. The relay UE1 may also receive D2D discovery information sent by an accessed UE, as well as connection establishment request information sent by other remote UEs that have not accessed and D2D information for discovering relay UEs. The D2D discovery information sent by the far end UE that has accessed the relay UE1 (i.e., the D2D UE that has established a connection with the relay UE) includes some or all of the following information: a remote UE identity, a type of the remote UE, a communication group identity of the remote UE, and the like. The far end UE looking for relay UEs sends the content included in the D2D information for finding a relay as described in step 3.

Further, the UE1 in the relay active state may transmit the relay broadcast information periodically using the relay discovery transmit resource or from which the transmit resource pool is randomly selected. The relay broadcast information may include a relay identifier, a relay type, a relay serving cell identifier, a relay available period, a relay group identifier, a relay mobility status indication, relay PLMN information, a relay prohibition status indication, and the like.

Application example 4

Officer a, B use D2D capable UE1 and UE2, respectively. UE1 is in a network covered state, while UE2 is in no network covered state. This example describes another flow for a relay UE to enter a relay active state from a relay inactive state. The UE1 with network coverage is interested in becoming a relay node and providing relay service for the UE without coverage. As shown in fig. 8, the method comprises the following steps:

step 1, the base station selects UE1 as a relay node, the base station sends device-through relay configuration information to UE1, and after UE1 receives the relay configuration information, if the configuration information indicates that relay power saving is enabled, UE1 enters a relay inactive state;

step 2, the relay UE1 receives the D2D information of the discovery relay sent by the remote UE on the relay discovery receiving resource pool;

the UE1 need not listen to the corresponding subframe on the subframe corresponding to the non-relay discovery reception resource pool. In addition, the relay UE1 may also monitor the information of D2D sent by the remote UE to discover the relay on the relay discovery receive resource pool according to the information of the relay inactive state monitoring period, the monitoring frame/subframe offset, the monitoring duration, and the like included in the relay configuration information.

Step 3, the remote UE2 sends relay discovery D2D information;

at this time, if the UE2 in the no-coverage state wishes to find the relay UE connected to the network transmission information, the UE2 first monitors the relay discovery reception resource pool to determine whether there is D2D relay broadcast information sent by the relay UE nearby. If the D2D relay broadcast information transmitted by the relay UE can be received, the remote UE2 selects one relay UE and transmits a relay connection establishment request to the selected relay UE. Assuming that the UE2 does not receive the D2D relay broadcast information transmitted by the relay UE at this time, the remote UE2 transmits D2D information to discover the relay.

The relay discovery D2D information sent by the remote UE2 includes some or all of the following: the relay searching indication, the identification of the remote UE, the type of the remote UE, the relay type searched by the remote UE, the communication target identification of the remote UE, the communication group identification of the remote UE, the priority of the remote UE and the like.

Step 4, the relay UE1 receives the D2D information of the remote UE2 sent the discovery relay, and determines that the UE2 is looking for the relay UE according to the message content, then the relay UE1 sends the relay response D2D information to the remote UE2 using the relay discovery sending resource or randomly selecting the resource from the relay discovery sending resource pool;

Step 5, the UE2 receives the relay response D2D information sent by the relay UE1, and sends a relay connection establishment request to the relay UE 1;

Step 6, when the relay UE1 receives the relay connection establishment request sent by the remote UE2, the relay UE1 sends relay connection establishment information to the remote UE2, so that the UE2 accesses the relay UE1 and the relay UE1 enters a relay active state.

The relay UE1 may subsequently receive the D2D communication information transmitted by the UE2 on a relay communication reception resource pool, transmit the D2D communication information to the remote UE2 using the relay communication transmission resource or randomly selecting a resource from the relay communication transmission resource pool. The relay UE1 may also receive D2D discovery information sent by an accessed UE, as well as connection establishment request information sent by other remote UEs that have not accessed and D2D information for discovering relays.

Further, the UE1 in the relay active state may periodically transmit D2D relay broadcast information using the relay discovery transmission resource or a random selection resource from which to relay the transmission resource pool. The D2D relay broadcast information may include some or all of the following: the relay mobile state indication method comprises a relay identification, a relay type, a relay service cell identification, a relay available time period, a relay group identification, a relay mobile state indication, relay PLMN information, a relay prohibition state indication and the like.

Application example 5

Officer a, B use D2D capable UE1 and UE2, respectively. UE1 is in a network covered state, while UE2 is in no network covered state. This example describes a remote UE relay activity state maintenance procedure, assuming that the base station selects UE1 as the relay node and that relay UE1 has entered the relay activity state. As shown in fig. 9, the method comprises the following steps:

step 1, the UE1 in relay active state may periodically transmit D2D relay broadcast information using a relay discovery transmission resource or randomly selecting a resource from a pool of relay discovery transmission resources. The D2D relay broadcast information may include a relay identifier, a relay type, a relay serving cell identifier, a relay available period, a relay belonging group identifier, a relay mobility status indication, relay PLMN information, a relay barring status indication, and the like. At this time, the UE2 in the non-coverage state wishes to find the relay UE connected to the network transmission information, the UE2 first monitors the relay discovery reception resource pool, determines whether there is D2D relay broadcast information sent by the relay UE nearby, and at this time, the UE2 receives the D2D relay broadcast information sent by the relay UE1, and then the remote UE2 sends a relay connection establishment request to the relay UE 1. When the relay UE1 receives the relay connection establishment request sent by the remote UE2, the relay UE1 sends relay connection establishment information to the remote UE2 to establish connection with the UE 2;

step 2, the UE1 starts an active state timer corresponding to the remote UE2 when the UE2 accesses;

step 3, the relay UE1 determines whether any one of the following events occurs, if so, executes step 4, otherwise, executes step 7: receiving the D2D communication information sent by the remote UE2 on a relay communication reception resource pool; transmitting the D2D communication information to the remote UE2 using the relay communication transmission resource or randomly selecting a resource from a relay communication transmission resource pool; the D2D discovery information sent by the remote UE2 is received.

Step 4, judging whether the received message is the connection release request information sent by the remote UE2, if so, executing step 6, otherwise, executing step 5;

step 5, the relay UE1 restarts the active state timer of the remote UE2, and returns to step 3;

the relay UE1 receiving the D2D communication information sent by the remote UE2, or the relay UE1 sending the D2D communication information to the remote UE2, or the relay UE1 receiving the D2D discovery information sent by the remote UE2, will trigger the relay UE1 to restart the remote UE2 active state timer.

Step 6, if the UE1 receives the connection release request information sent by the UE2, the UE1 sends the connection release information to the UE2, and step 8 is executed;

step 7, judging whether the activity state timer of the remote UE2 is overtime, if yes, executing step 8, otherwise, returning to step 3;

step 8, the UE1 releases the connection with the remote UE2 and the saved context of the UE 2.

In addition, the relay UE1 may send D2D information or paging information to the remote UE2 to discover the remote UE2 when the activity status timer of the remote UE2 times out, and the relay UE1 may release the connection with the remote UE2 if no response information sent by the remote UE2 is received within a predetermined time.

Application example 6

Officers a, B, and C use D2D-enabled UE1, UE2, and UE3, respectively. UE1 is in network coverage state, while UE2, UE3 are in no network coverage. This example describes the flow of relay UEs from the relay active state to the relay inactive state, in this example, the relay UE1 sets an active state timer for each remote UE, as shown in fig. 10, including the following steps:

step 1, the base station selects UE1 as a relay node, relay power saving is enabled, and relay UE1 enters a relay active state;

step 2, both the UE2 and the UE3 in the non-coverage state have access to the relay UE1, and the relay UE1 starts active state timers corresponding to the UE2 and the UE3 when the UE2 and the UE3 are accessed;

step 3, the relay UE1 may determine whether the connection with the UE2 needs to be released or not and whether the connection with the UE3 needs to be released or not by using the method in example 5 (step 3-7 in example 5), if so, execute step 4, otherwise, return to this step;

in step 4, the relay UE1 successively releases the connections with the UE2 and the UE3, and the UE1 enters the relay inactive state.

Application example 7

Officers a, B, and C use D2D-enabled UE1, UE2, and UE3, respectively. UE1 is in a network covered state, while UE2 and UE3 are in no network covered. This example describes the flow of relay UEs from relay active state to relay inactive state, in this example, the relay UE1 maintains a relay active state timer of its own, as shown in fig. 11, and includes the following steps:

step 1, the base station selects the UE1 as a relay node and sends relay configuration information to the relay node, and after the UE1 receives the relay configuration information, if the configuration information indicates that the relay function is activated and relay power saving is enabled, the UE1 enters a relay inactive state;

step 2, the relay UE1 monitors the D2D discovery information sent by the remote UE on the relay discovery receiving resource pool, the relay UE1 receives the D2D discovery information sent by the remote UE2, and determines that the UE2 is searching for the relay UE according to the message content, then the UE1 enters a relay active state, and starts a relay active state timer at the same time;

step 3, the relay UE1 establishes connection with the remote UE2 and the UE3 and forwards data for the remote UE2 and the UE3, the relay UE1 determines whether any one of the following events occurs, if so, step 4 is executed, otherwise, step 5 is executed: the relay UE1 receives the D2D communication information transmitted by the UE2 or UE3 on the relay communication reception resource pool; the relay UE1 transmits D2D communication information to the remote UE2 or UE3 using the relay communication transmission resource or randomly selecting a resource from a relay communication transmission resource pool; the relay UE1 receives the D2D discovery information sent by the UE2 or UE 3;

step 4, the relay UE1 restarts the relay active state timer, and returns to step 3;

step 5, the relay UE1 determines whether the relay activity status timer maintained by the relay UE is overtime, if yes, step 6 is executed, otherwise, step 3 is returned;

step 6, the relay UE1 enters the relay inactive state again, and only monitors the D2D discovery information for searching the relay UE sent by the remote UE on the relay discovery receiving resource pool.

Application example 8

Officer a, B use D2D capable UE1 and UE2, respectively. UE1 is in a network covered state, while UE2 is in no network covered state. The UE1 with network coverage is interested in becoming a relay node and providing relay service for the UE without coverage. The UE1 activates the relay function according to the preconfigured relay configuration information and enables power saving, at which point the UE1 enters a relay inactive state and starts receiving discovery relay D2D information sent by the remote UE on the relay discovery receive resource pool. The UE1 may send a relay status indication to a serving base station of the UE1 upon entering a relay inactivity state, wherein the relay status indication may further indicate the relay inactivity state. Assuming that the relay UE1 receives the discovery relay D2D information sent by the remote UE2 and determines from the message content that the UE2 is looking for a relay UE, the UE1 enters a relay active state, and similarly, the UE1 may send a relay status indication to the serving base station of the UE1 after entering the relay active state, where the relay status indication may further indicate the relay active state. When the relay UE1 is no longer acting as a relay node, the UE1 may also send a relay status indication to the serving base station of the UE1, where the relay status indicates that the UE1 is no longer acting as a relay node.

Although the embodiments of the present invention have been described above, the above description is only for the convenience of understanding the present invention, and is not intended to limit the present invention. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. A method for determining a relay state of a device-through system is characterized by comprising the following steps:

2. The method of claim 1,

the relay UE acquiring relay configuration information includes:

3. The method of claim 2,

the relay discovery resource or resource pool information includes: a relay discovery transmitting resource or resource pool, a relay discovery receiving resource pool; the relay communication resource or resource pool information includes: the relay communication sending resource or resource pool, and the relay communication receiving resource pool.

4. The method of claim 3,

the relay discovery transmission resource or resource pool comprises at least one of: D2D discovery with coverage sends resources or resource pools, D2D discovery without coverage sends resource pools; the relay discovery reception resource pool includes: coverage D2D discovery receive resource pool, and non-coverage D2D discovery receive resource pool; wherein: the covered D2D discovery receiving resource pool includes a D2D discovery transmitting resource pool of the relay UE serving cell and a D2D discovery transmitting resource pool corresponding to a neighboring cell of the relay UE serving cell.

5. The method of claim 2,

the relay configuration information further includes one or more of: relaying the first state listening period, listening frame offset, listening subframe offset, listening duration.

6. The method of claim 1,

the relay UE determines a relay state of the relay UE according to the relay configuration information, and the method comprises the following steps:

7. The method of claim 1,

the relay UE determines the relay state of the relay UE according to the relay configuration information and/or the D2D information, and the method comprises the following steps:

8. The method of claim 7,

after receiving the relay discovery D2D information sent by the remote UE, the relay UE interacts with the remote UE, and after establishing a connection with the remote UE, enters a relay second state, including:

9. The method of claim 1,

the relay UE determines the relay state of the relay UE according to the relay configuration information and the D2D information, and the method comprises the following steps:

10. The method of claim 9,

after the relay UE starts the relay activity status timer, the method further includes:

11. The method of claim 1,

12. The method of claim 11,

after the relay UE sets and starts a corresponding active state timer for the remote UE, the method further includes:

13. The method of claim 1,

determining that a relay status of the relay UE is a relay first status, the method further comprising: the relay UE in the relay first state performs one of the following operations:

receiving D2D information for discovering the relay sent by the remote UE;

14. The method of claim 1,

determining that the relay status of the relay UE is a relay second status, the method further comprising: the relay UE in the relay second state performs one or more of the following operations:

periodically sending relay broadcast information;

15. The method of claim 14,

the method further comprises the following steps: and after receiving the relay broadcast information sent by the relay UE in the relay second state, the remote UE which is not accessed to the relay UE selects one relay UE and sends a relay connection establishment request to the selected relay UE, and after receiving the relay connection establishment request, the relay UE sends the relay connection establishment information to the remote UE.

16. The method of claim 1,

after the relay UE determines the relay status of the relay UE, the method further includes: and the relay UE reports the relay state of the relay UE to the base station.

17. A device-through system relay state determination device is located in a relay User Equipment (UE), and is characterized by comprising an information acquisition module and a state determination module, wherein:

18. The apparatus of claim 17,

the information acquisition module acquires relay configuration information, including:

19. The apparatus of claim 17,

the state determination module determines a relay state of the relay UE according to the relay configuration information, including:

20. The apparatus of claim 17,

the state determination module determines a relay state of the relay UE according to the relay configuration information and/or the D2D information, including:

21. The apparatus of claim 20,

the state determination module interacts with the remote UE after receiving relay discovery D2D information sent by the remote UE, and determines that the relay UE enters a relay second state after the relay UE establishes a connection with the remote UE, including:

22. The apparatus of claim 17,

the state determination module determines the relay state of the relay UE according to the relay configuration information and the D2D information, including:

23. The apparatus of claim 22,

the state determining module is further configured to, after the relay activity state timer is started, restart the relay activity state timer if any one of the following events occurs:

24. The apparatus of claim 17,

25. The apparatus of claim 24,

the state determining module is further configured to, after setting and starting a corresponding active state timer for the remote UE, determine that any one of the following events occurs, and restart the active state timer corresponding to the remote UE:

26. The apparatus of claim 17,

the status determining module determines that the relay status of the relay UE is a relay first status, and the apparatus further includes a first module configured to perform one of the following operations:

receiving D2D information for discovering the relay sent by the remote UE;

27. The apparatus of claim 17,

the state determining module determines that the relay state of the relay UE is a relay second state, and the apparatus further includes a second module configured to perform one or more of the following operations:

periodically sending relay broadcast information;

28. The apparatus of claim 27,

the second module is further to: and after receiving a relay connection establishment request sent by a remote UE which is not accessed to the relay UE, sending relay connection establishment information to the remote UE.

29. The apparatus of claim 17,

the device also comprises a reporting module used for reporting the relay state of the relay UE to a base station after the state determining module determines the relay state of the relay UE.