KR20150051128A - Methods for transmitting the device-to-device communication status report and Apparatuses thereof - Google Patents

Abstract

The present invention relates to a direct communication between terminals which allows to directly transmit and receive data without relay of a base station between a plurality of terminals, and more specifically, to a method and device for transmitting a status report required for performing direct communication between terminals to the base station. Particularly, the present invention provides a method for transmitting a status report required for performing direct communications between terminals, the method comprising the steps of: receiving a first signal including setting information of direct communication between terminals from a base station or an entity for allocating radio resource; confirming a trigger of a status report of direct communication between terminals based on trigger condition information; and transmitting a second signal including a status report of direct communication between terminals to the base station or the entity for allocating radio resource.

Description

Technical Field [0001] The present invention relates to a method and apparatus for reporting a direct communication state between terminals,

The present invention relates to a direct communication between terminals that directly exchanges data between a plurality of terminals without going through a base station, and a method and apparatus for transmitting a status report related to direct communication between terminals to a base station.

As the spread of mobile terminals such as smart phones, tablet PCs, and various service requests using such mobile terminals have been developed, it becomes possible to transmit and receive data or signals directly between terminals without passing through network infrastructures such as base stations and access points Direct communication has been highlighted.

For example, an LTE (Long Term Evolution) or an LTE-Advanced network (hereinafter referred to as " LTE-Advanced ") or the like for providing more various services to users or assuring the reliability of direct communication between terminals, There has been a demand for a technology for supporting direct communication between terminals by using radio resources of various mobile communication networks.

However, at present, technologies for efficiently supporting direct communication between terminals using radio resources of an existing communication network, for example, a mobile communication network such as LTE (Long Term Evolution) or LTE-Advanced network, have not been developed .

In addition, a method for efficiently allocating radio resources is required by using radio resources of existing mobile communication networks in direct communication between terminals. For this, the base station needs to recognize accurate information related to the direct communication between the terminals and determine the allocation of radio resources based on the information.

In accordance with such a demand, the base station needs to receive information related to direct-to-terminal communication within its coverage.

In addition, there is a need to establish a specific and efficient procedure for the terminal to transmit information related to direct communication between the terminals to the base station.

According to another aspect of the present invention, there is provided a method for transmitting a direct communication status report between terminals, the method comprising: receiving a first signal including direct communication setting information from a base station or a radio resource allocation entity; Confirming a trigger of the inter-terminal direct communication status report based on the condition information, and transmitting a second signal including the inter-terminal direct communication status report to the base station or the radio resource allocation entity.

The present invention also provides a method of receiving a direct communication status report between terminals, the method comprising: generating a first signal including direct communication setting information between terminals; transmitting a first signal to the terminal; And receiving a second signal comprising an inter-direct communication status report.

According to another aspect of the present invention, there is provided a terminal for transmitting a direct communication status report between terminals, comprising: a receiver for receiving a first signal including direct communication setting information between terminals from a base station or a radio resource allocation entity; A control unit for confirming a trigger of the direct communication status report, and a transmitter for transmitting a second signal including a direct communication status report between terminals to the base station or the radio resource allocation entity.

The present invention also provides a base station for receiving a direct communication status report between terminals, comprising: a controller for generating a first signal including direct communication setting information between terminals; a transmitter for transmitting the first signal to the terminal; And a receiver for receiving a second signal including a communication status report.

As described above, according to the present invention, a terminal can transmit status information related to direct communication between terminals to a base station.

Also, the base station receives the status information related to the direct communication between the terminals from the terminal, and effectively allocates the radio resources for the direct communication between the terminals. Therefore, there is an effect that the limited radio resources can be efficiently distributed.

1 is a signal diagram illustrating an example of downlink transmission using a semi-persistent scheduling scheme.
2 is a signal diagram illustrating an example of uplink transmission using a semi-persistent scheduling scheme.
FIG. 3 is a diagram illustrating an example of a direct-to-terminal direct communication scenario to which the present invention can be applied.
4 is a diagram illustrating another example of a direct-to-terminal communication scenario to which the present invention can be applied.
5 is a diagram illustrating operations of a terminal and a base station according to an embodiment of the present invention.
6 is a diagram illustrating an operation of a terminal and a base station according to another embodiment of the present invention.
7 is a diagram illustrating an example of information that can be included in the inter-terminal direct communication configuration information according to another embodiment of the present invention.
8 is a diagram illustrating an example of information that may be included in the inter-terminal direct communication status report information according to another embodiment of the present invention.
9 is a diagram illustrating operations of a terminal and a base station in a case where a direct communication discovery failure occurs between terminals in accordance with another embodiment of the present invention.
FIG. 10 is a diagram illustrating operations of a terminal and a base station when a direct communication between terminals fails in accordance with another embodiment of the present invention.
11 is a flowchart illustrating an operation of a terminal according to another embodiment of the present invention.
12 is a flowchart illustrating an operation of a base station according to another embodiment of the present invention.
13 is a diagram illustrating a configuration of a terminal according to another embodiment of the present invention.
14 is a diagram illustrating a configuration of a base station according to another embodiment of the present invention.

Hereinafter, some embodiments of the present invention will be described in detail with reference to exemplary drawings. It should be noted that, in adding reference numerals to the constituent elements of the drawings, the same constituent elements are denoted by the same reference numerals even though they are shown in different drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

The wireless communication system in the present invention is widely deployed to provide various communication services such as voice, packet data and the like. A wireless communication system includes a user equipment (UE) and a base station (BS, or eNB). The user terminal in this specification is a comprehensive concept of a terminal in wireless communication. It is a comprehensive concept which means a mobile station (MS), a user terminal (UT), an SS (User Equipment) (Subscriber Station), a wireless device, and the like.

A base station or a cell generally refers to a station that communicates with a user terminal and includes a Node-B, an evolved Node-B (eNB), a sector, a Site, a BTS A base transceiver system, an access point, a relay node, a remote radio head (RRH), a radio unit (RU), and a small cell.

That is, in the present specification, a base station or a cell has a comprehensive meaning indicating a part or function covered by BSC (Base Station Controller) in CDMA, Node-B in WCDMA, eNB in LTE or sector (site) And covers various coverage areas such as megacell, macrocell, microcell, picocell, femtocell and relay node, RRH, RU, and small cell communication range.

Since the various cells listed above exist in the base station controlling each cell, the base station can be interpreted into two meanings. i) the device itself providing a megacell, macrocell, microcell, picocell, femtocell, small cell in relation to the wireless region, or ii) indicating the wireless region itself. i indicate to the base station all devices that are controlled by the same entity or that interact to configure the wireless region as a collaboration. An eNB, an RRH, an antenna, an RU, an LPN, a point, a transmission / reception point, a transmission point, a reception point, and the like are exemplary embodiments of a base station according to a configuration method of a radio area. ii) may indicate to the base station the wireless region itself that is to receive or transmit signals from the perspective of the user terminal or from a neighboring base station.

Therefore, a base station is collectively referred to as a base station, collectively referred to as a megacell, macrocell, microcell, picocell, femtocell, small cell, RRH, antenna, RU, low power node do.

Herein, the user terminal and the base station are used in a broad sense as the two transmitting and receiving subjects used to implement the technical or technical idea described in this specification, and are not limited by a specific term or word. The user terminal and the base station are used in a broad sense as two (uplink or downlink) transmitting and receiving subjects used to implement the technology or technical idea described in the present invention, and are not limited by a specific term or word. Here, an uplink (UL, or uplink) means a method of transmitting / receiving data to / from a base station by a user terminal, and a downlink (DL or downlink) .

There are no restrictions on multiple access schemes applied to wireless communication systems. Various multiple access schemes such as Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Orthogonal Frequency Division Multiple Access (OFDMA), OFDM-FDMA, OFDM- Can be used. An embodiment of the present invention can be applied to asynchronous wireless communication that evolves into LTE and LTE-Advanced via GSM, WCDMA, and HSPA, and synchronous wireless communication that evolves into CDMA, CDMA-2000, and UMB. The present invention should not be construed as limited to or limited to a specific wireless communication field and should be construed as including all technical fields to which the idea of the present invention can be applied.

A TDD (Time Division Duplex) scheme in which uplink and downlink transmissions are transmitted using different time periods, or an FDD (Frequency Division Duplex) scheme in which they are transmitted using different frequencies can be used.

In systems such as LTE and LTE-Advanced, the uplink and downlink are configured on the basis of one carrier or carrier pair to form a standard. The uplink and the downlink are divided into a Physical Downlink Control Channel (PDCCH), a Physical Control Format Indicator CHannel (PCFICH), a Physical Hybrid ARQ Indicator CHannel, a Physical Uplink Control CHannel (PUCCH), an Enhanced Physical Downlink Control Channel (EPDCCH) Transmits control information through the same control channel, and is configured with data channels such as PDSCH (Physical Downlink Shared CHannel) and PUSCH (Physical Uplink Shared CHannel), and transmits data.

On the other hand, control information can also be transmitted using EPDCCH (enhanced PDCCH or extended PDCCH).

In this specification, a cell refers to a component carrier having a coverage of a signal transmitted from a transmission point or a transmission point or transmission / reception point of a signal transmitted from a transmission / reception point, and a transmission / reception point itself .

The wireless communication system to which the embodiments are applied may be a coordinated multi-point transmission / reception system (CoMP system) or a coordinated multi-point transmission / reception system in which two or more transmission / reception points cooperatively transmit signals. antenna transmission system, or a cooperative multi-cell communication system. A CoMP system may include at least two multipoint transmit and receive points and terminals.

The multi-point transmission / reception point includes a base station or a macro cell (hereinafter referred to as 'eNB'), and at least one mobile station having a high transmission power or a low transmission power in a macro cell area, Lt; / RTI >

Hereinafter, a downlink refers to a communication or communication path from a multipoint transmission / reception point to a terminal, and an uplink refers to a communication or communication path from a terminal to a multiple transmission / reception point. In the downlink, a transmitter may be a part of a multipoint transmission / reception point, and a receiver may be a part of a terminal. In the uplink, the transmitter may be a part of the terminal, and the receiver may be a part of multiple transmission / reception points.

Hereinafter, a situation in which a signal is transmitted / received through a channel such as PUCCH, PUSCH, PDCCH, EPDCCH, and PDSCH is expressed as 'PUCCH, PUSCH, PDCCH, EPDCCH and PDSCH are transmitted and received'.

In the following description, an indication that a PDCCH is transmitted or received or a signal is transmitted or received via a PDCCH may be used to mean transmitting or receiving an EPDCCH or transmitting or receiving a signal through an EPDCCH.

That is, the physical downlink control channel described below may mean a PDCCH, an EPDCCH, or a PDCCH and an EPDCCH.

Also, for convenience of description, EPDCCH, which is an embodiment of the present invention, may be applied to the portion described with PDCCH, and EPDCCH may be applied to the portion described with EPDCCH according to an embodiment of the present invention.

Meanwhile, the High Layer Signaling described below includes RRC signaling for transmitting RRC information including RRC parameters.

The eNB performs downlink transmission to the UEs. The eNB includes a physical downlink shared channel (PDSCH) as a main physical channel for unicast transmission, downlink control information such as scheduling required for reception of a PDSCH, A physical downlink control channel (PDCCH) for transmitting scheduling grant information for transmission in a Physical Uplink Shared Channel (PUSCH). Hereinafter, the transmission / reception of a signal through each channel will be described in a form in which the corresponding channel is transmitted / received.

The base station or the radio resource allocation entity may allocate radio resources for data transmission / reception of the UE. The BS may allocate uplink radio resources based on the buffer status information received from the UE, or may allocate radio resources to transmit downlink data and signals.

The base station or the radio resource allocation entity may allocate radio resources in various manners. A method of dynamically allocating radio resources and a method of allocating radio resources for a predetermined period of time can be considered. Hereinafter, a semi-persistent scheduling (SPS) scheme is described as an example in which a BS or a radio resource allocation entity allocates radio resources

Semi-Persistent Scheduling is a scheduling scheme for services where small-sized data transmissions such as Voice over Internet Protocol (VoIP) occur repeatedly in a short period of time. For example, when the terminal transmits and receives data for voice communication, voice packets of similar size are generated and transmitted at regular intervals. That is, the base station must allocate a similar amount of radio resources in a predetermined period in order for the UE to transmit the corresponding packet. If a dynamic scheduling scheme is used for the VoIP service, a large number of PDCCHs are used to continuously transmit downlink assignment and UL grant information. Since the number of PDCCHs is limited, if one terminal uses a large number of PDCCHs, the number of users that the base station can service in the cell can be reduced. Therefore, in order to minimize the load of the PDCCH, a method of scheduling resources of a predetermined size periodically for a long period of time is a Semi-Persistent Scheduling (SPS) scheme.

1 is a signal diagram illustrating an example of downlink transmission using a semi-persistent scheduling scheme.

Specifically, referring to FIG. 1, the BS 101 may schedule a radio resource for downlink data transmission to the UE 109. For example, the base station 101 may transmit an upper layer signaling including the SPS configuration information (SPS-config) to the terminal 109 (S110). As an example, the upper layer signaling may be an RRC Reconfiguration message.

Thereafter, the base station 101 may transmit a PDCCH for activation of the SPS to the terminal 109 (S120). When the terminal 109 receives the PDCCH, the base station 101 transmits downlink data (S130, S140, S150).

When the downlink data transmission is completed, the base station 101 may transmit the PDCCH for terminating the SPS scheduling (S160). Through such a procedure, the base station can transmit a small amount of data periodically generated to the mobile station through a single scheduling. Accordingly, it is possible to reduce the consumption of the PDCCH resources due to the downlink data transmission, which occurs each time.

2 is a signal diagram illustrating an example of uplink transmission using a semi-persistent scheduling scheme.

2, the Node B 201 may schedule a radio resource for uplink data reception from the UE 209. FIG. For example, the base station 201 may transmit an upper layer signaling including the SPS configuration information (SPS-config) to the terminal 209 (S210). As an example, the upper layer signaling may be an RRC Reconfiguration message.

Then, the base station 201 may transmit a PDCCH for activation of the SPS to the terminal 209 (S220). Upon receiving the PDCCH including the SPS activation information, the terminal 209 transmits the uplink data to the base station 201 (S230, S240, S250).

When the uplink data transmission of the UE 209 ends, the BS 201 can transmit a PDCCH for terminating the SPS scheduling (S260). In another example, the base station 201 may not transmit a PDCCH terminating SPS scheduling. In this case, the SPS scheduling can be terminated if uplink data is not received for a predetermined time or a predetermined number of times. Through such a procedure, the UE can transmit a small amount of data periodically generated to the Node B through a single scheduling. Therefore, it is possible to reduce the consumption of the PDCCH resources due to the uplink data transmission, which occurs every time.

Each embodiment of the present invention described below can be applied to the SPS system described above. Also, the present invention can be applied to a method of allocating radio resources dynamically to a terminal by a base station, and a method of performing overall scheduling according to a data transmission state of the terminal.

In the present specification, direct communication between terminals means D2D (Device to Device) communication. In addition, it means various communication in which direct communication is performed between terminals without using a base station using radio resources. Hereinafter, D2D communication will be described as an example of direct communication between terminals with reference to the drawings.

Recently, a method for providing direct communication between terminals, which directly exchanges data without passing through a base station, between adjacent terminals in a 3GPP LTE / LTE-Advanced system, for example, a proximity service through D2D is being discussed .

The D2D communication can take the scenarios shown in Figs. 3 and 4 into account.

FIG. 3 is a diagram illustrating an example of a direct-to-terminal direct communication scenario to which the present invention can be applied.

Referring to FIG. 3, scenario 1A is a case where UE1 and UE2 performing D2D communication are located outside the coverage of the mobile communication base station. That is, both UE1 and UE2 are located outside the coverage of the mobile communication base station, but are capable of performing D2D communication and transmitting and receiving data and signals.

Scenario 1B is a case where UE1 performing D2D communication is located within the coverage of the mobile communication base station, and UE2 is located outside coverage. Even in this case, UE1 and UE2 can transmit and receive data and signals.

4 is a diagram illustrating another example of a direct-to-terminal communication scenario to which the present invention can be applied.

Referring to FIG. 4, scenario 1C is a case where both UE1 and UE2 performing D2D communication are located within the coverage of the mobile communication base station. Even in this case, UE1 and UE2 can transmit and receive data and signals without going through the base station.

Scenario 1D is a case where UE1 and UE2 performing D2D communication are all located within the coverage of the mobile communication base station, but each UE is located within the coverage of different cells. That is, UE1 is located within the coverage of the first base station, and UE2 is located within the coverage of the second base station. Even in this case, UE1 and UE2 can directly transmit and receive data and signals without going through the base station.

In this way, in the direct-to-terminal direct communication, the terminal can perform communication with the target terminal using radio resources. Therefore, it is necessary to allocate radio resources according to the terminal performing the direct communication between the terminals. In addition, the terminal may be required to perform an operation of searching for a target terminal that is an object of direct communication between terminals. For this purpose, when a discovery procedure for direct communication between terminals is required, allocation of radio resources for discovery is required. For example, a direct communication discovery radio resource allocation method may be used as follows. For example, a method of assigning radio resources in common to terminal groups or terminals for direct communication between terminals can be considered. As another example, a method of allocating radio resources for each terminal for direct communication between terminals may be considered. Specifically, a method of allocating radio resources for each UE may be a method of allocating radio resources each time a transmission request is generated. Or a radio resource allocation method according to the semi-persistent scheme described above.

Meanwhile, the radio resource allocation entity may mean an entity that performs at least one of radio resource allocation, sink channel transmission, and group management for direct communication for direct communication between terminals. That is, the D2D communication may be referred to as a cluster head, a central control entity, a central entity, or the like, for example, in a radio resource allocation entity. From a functional point of view, refers to an entity that performs a part of the role of a base station such as a radio resource allocation, a sink channel transmission, or a D2D group management when the terminals are located outside the coverage of the D2D communication scenario. Hereinafter, for convenience of explanation, the base station will be described as an example, but the operation of including the above-described radio resource allocation entity in place of the base station is also included in the scope of the present invention.

As described above, it is difficult for the base station to know how much the direct communication between the terminals is currently performed in its coverage or how many terminals are in direct communication between the terminals. Therefore, it is difficult to accurately determine whether or not the radio resources allocated for direct communication between terminals are insufficient or excessive. This may cause a problem that the limited radio resources can not be efficiently used.

Therefore, it is necessary for the base station to grasp the direct communication state between the terminals of the terminals that are currently performing their coverage. Through this, the base station can allocate and allocate radio resources based on the state information of the direct communication between the terminals. That is, the base station can efficiently manage the limited radio resources, and the terminal can be allocated an appropriate amount of radio resources for direct communication between the terminals, thereby efficiently performing direct communication between the terminals.

Hereinafter, each embodiment of the present invention for efficiently allocating radio resources will be described in detail by way of example.

5 is a diagram illustrating operations of a terminal and a base station according to an embodiment of the present invention.

A method for transmitting a direct communication status report between terminals in a terminal according to an embodiment of the present invention includes receiving a first signal including direct communication setting information from a base station or a radio resource allocation entity, And a step of transmitting a second signal including a direct communication status report between terminals to the base station or the radio resource allocation entity.

Referring to FIG. 5, for example, a base station or a radio resource allocation entity 501 transmits a first signal including direct communication setting information between terminals to the terminal 509 (S510). The direct communication setting information between the terminals may include setting information necessary for the terminal to perform direct communication between the terminals and to report the direct communication state between the terminals. For example, the direct communication configuration information between terminals may include radio resource allocation information for direct communication between terminals. As another example, the direct communication setting information between terminals may include setting information for direct communication status reporting between terminals. As another example, it may include both the radio resource allocation information for direct communication between terminals and the direct communication status report setting information between terminals.

Meanwhile, the first signal transmitted by the base station or the radio resource allocation entity 501 to the UE 509 may be transmitted in a system information block (SIB) or a higher layer signaling. The higher layer signaling may be RRC signaling.

The terminal 509 receiving the first signal can confirm the trigger of the inter-terminal direct communication status report based on the trigger condition information (S520). The trigger condition information may be included in the first signal and transmitted. Or the terminal 509 in advance. For example, when the terminal 509 receives a first signal and performs direct communication between the terminals, a direct communication state report may be triggered when a direct communication failure occurs between the terminals. Or a direct communication status report between the terminals may be triggered based on a predetermined number of times or a certain period of time. Alternatively, the trigger condition information may be set at regular intervals. The trigger condition information may be included in the inter-terminal direct communication setting information of the first signal and may be received by the terminal 509 or preset in the terminal 509. [ Or parameter information related to the status reporting criteria is transmitted to the terminal 509, and the terminal 509 may confirm the trigger based on the parameter information.

If the trigger condition checked in step S520 is satisfied, the terminal 509 can transmit a second signal including the inter-terminal direct communication status report to the base station or the radio resource allocation entity 501. [ The direct communication status report between terminals may include information related to discovery failure for direct communication between terminals or information related to direct communication failure between terminals. In addition, the second signal may include at least one of information related to the target terminal, information related to the amount of data to be transmitted / received through direct communication between terminals, data transfer success rate information, and information related to group communication, . In addition, the terminal may include various information such as time and location information for performing direct communication between the terminals. More specifically, for example, the second signal may include a report on direct communication between terminals, a number of direct communication terminals between terminals, a number of direct communication sessions between terminals, a failure frequency of attempts to transmit a direct communication discovery message, Report the number of transmission attempt failures, report throughput of the terminal performing direct communication between the terminals, and report buffer status of the terminal. This information may be included in the direct communication status report between the terminals.

The base station or radio resource allocation entity 501 may receive the second signal from the terminal 509 and adjust the amount of radio resource allocation based on the inter-terminal communication status report information.

1st Example : When direct communication between terminals is performed successfully

6 is a diagram illustrating an operation of a terminal and a base station according to another embodiment of the present invention.

Referring to FIG. 6, an operation of each step of transmitting an inter-terminal direct communication status report when the terminal successfully performs direct communication between terminals will be described.

In step S610, the base station 601 transmits the direct communication configuration information between terminals in order to know the direct communication status between the terminals. The direct communication setup information between the corresponding terminals may be transmitted to the SIB or may be transmitted through higher layer signaling. Through the SIB, it is possible to transmit the direct communication status report setting information between the terminals such as the number of direct communication terminals, the number of direct communication sessions between terminals, and the number of failed communication attempts between terminals. Alternatively, the base station 601 may transmit status report setting information together with inter-terminal direct communication discovery radio resource allocation information to the terminal 609 desiring direct communication between the terminals through an RRC message.

7 is a diagram illustrating an example of information that can be included in the inter-terminal direct communication configuration information according to another embodiment of the present invention.

The inter-terminal direct communication setup information transmitted from the base station 601 to the terminal 609 may include information related to the D2D radio resource allocation information and information related to the D2D communication status report setup information, as shown in FIG. Although FIG. 7 illustrates D2D as an example, the present invention can be applied to all cases where direct communication is performed between terminals.

Thereafter, the terminal 609 can transmit / receive a direct communication discovery message to / from the target terminal 602 according to the direct communication setting information between terminals (S620). The discovery message performs a preparation task for searching for the target terminal 602 and performing communication before the terminal 609 performs direct communication between the terminals.

If the terminal 609 succeeds in transmitting / receiving the direct communication discovery message between terminals, the terminal 609 performs communication between the terminals using the radio resource allocated from the base station 601 (S630).

Thereafter, the terminal 609, which is in communication between the terminals, can confirm whether or not the inter-terminal direct communication status report is triggered based on the above-described direct communication setting information. Or whether the trigger satisfies the trigger based on the trigger condition information preset in the terminal 609. [ If the trigger condition is satisfied, the terminal 609 transmits a direct communication status report to the base station 601 (S640).

As another example, the terminal 609 may transmit a direct communication status report when receiving a report request message about the inter-terminal direct communication status from the base station 601. That is, the terminal can transmit a direct communication status report between the terminals according to the request of the base station. In this case, the trigger condition information may be the reception of the request message transmitted to the mobile station by the base station.

8 is a diagram illustrating an example of information that may be included in the inter-terminal direct communication status report information according to another embodiment of the present invention.

The inter-terminal direct communication status report may include a plurality of information related to inter-terminal direct communication as shown in FIG. FIG. 8 exemplarily shows information included in an inter-terminal direct communication status report in the case of D2D as an example of direct communication between terminals. Accordingly, the direct communication status report between the terminals may include various information necessary for the base station to allocate the radio resources, such as the location information related to the direct communication between the terminals.

The base station can adjust the radio resource allocation of the terminal based on the received direct communication status report between the terminals. For example, it is possible to perform operations such as termination or additional allocation of radio resource allocation.

Second Example : When the attempt to transmit the direct communication discovery message between the terminals fails

9 is a diagram illustrating operations of a terminal and a base station in a case where a direct communication discovery failure occurs between terminals in accordance with another embodiment of the present invention.

If the terminal 909 fails to transmit a direct communication discovery message between the terminals for a predetermined time or fails more than a predetermined number of times, the terminal 909 stops discovery transmission and transmits a failure report including information on the number of failures and duration Report to the base station.

For example, the base station 901 may transmit discovery message transmission setup information for direct communication between terminals to the terminal 909. For example, the discovery message transmission setup information may include at least one of radio resource allocation information, maximum discovery message transmission attempt number information, and maximum discovery message transmission attempt time information. In addition, the discovery message transmission setting information may be included in the inter-terminal direct communication setting information described with reference to FIG. Therefore, it can be transmitted via SIB or RRC message.

The terminal 909 attempts to transmit the discovery message using the radio resource based on the discovery message transmission setting information that can be included in the inter-terminal direct communication setting information received from the base station 901. [ In this case, the transmission of the discovery message of the terminal 909 may fail. For example, if a plurality of terminals attempt to transmit a discovery message using the same radio resource, the corresponding discovery message transmission may fail (S920).

The terminal 909 that has failed to transmit the discovery message may retransmit the discovery signal using the same or another radio resource after a predetermined time. When the terminal 909 retransmits the discovery message, information such as a predetermined time or the number of times of retransmission may be included in the above-described discovery message transmission setting information. Or a value preset in the terminal.

If the terminal 909 transmits the discovery message for a certain number of times or for a predetermined time, it may fail (S925).

In this case, the terminal 909 confirms the trigger condition for transmitting the discovery failure related information to the base station 901 (S930). For example, the trigger condition may be included in the direct communication setting information between terminals or may be preset in the terminal. For example, the trigger condition may include a case where a transmission attempt of the discovery message of the UE fails more than a predetermined number of times, a transmission attempt fails for a predetermined time period, a period set to report periodically is satisfied, Or a case in which one of them is used.

If the trigger condition is satisfied, the terminal 909 transmits discovery failure related information for direct communication between the terminals to the base station 901 (S940). The discovery failure related information may be included in the inter-terminal direct communication status report described in FIG.

The information related to the failure of the discovery may include various information such as the cause of the failure of the terminal to perform the discovery. As an example, the discovery failure related information may include one or more of the following information.

- Failed Number of Discovery Message Transmission Attempt Attempts: It may include information related to the time set from the base station or the number of unsuccessful attempts to transmit the discovery message for a preset time period.

- Duration of discovery message transmission attempt: Duration information may include time information from the first failure to the discovery message transmission attempt or time information from the first failure to just before the first success.

- Location information of the terminal: It may include the current location information of the terminal. The current location information of the terminal can be obtained from a positioning system such as GPS or GNSS. Or the serving cell and / or neighbor cell measurement information measured according to the measurement operation of the terminal.

- Identification information of the direct communication group between the terminals to which the terminal belongs: It may include identification information used by the terminal for communication of a group (for example, a D2D group) in direct communication between the terminals. In one example, the identification information may be a specific value used to distinguish the group, such as an identifier or an index.

- Data amount for direct communication transmission between terminals: Buffer information related to direct communication between terminals can be included.

The base station 901 may perform reallocation of radio resources or change and allocate radio resources based on received discovery failure related information.

Third Example : When direct communication data transmission between terminals fails

FIG. 10 is a diagram illustrating operations of a terminal and a base station when a direct communication between terminals fails in accordance with another embodiment of the present invention. 10 is a diagram illustrating an example of a case where a UE successfully transmits and receives a discovery message but fails to transmit data. In this case, the UE transmits to the BS the information related to the direct communication failure between UEs related to the failure of data transmission.

Each step will be described in detail with reference to FIG.

The terminal 1009 desiring direct transmission of the inter-terminal communication can receive inter-terminal direct communication setting information from the base station 1001 (S1010). The direct communication setup information may include radio resource allocation information for direct communication between terminals, discovery message transmission setting information, and the like. The terminal 1009 may attempt to transmit / receive data by selecting some or all of the radio resources allocated for direct communication between terminals. The wireless resource information may be included in a direct communication discovery message transmitted or received by the terminal 1009. [ Also, as described above, it may be included in the direct communication setting information received from the base station 1001 through SIB or upper layer signaling.

The terminal 1009 may attempt to transmit / receive data for direct communication between terminals, and may fail in this case (S1020). If a failure occurs in data transmission / reception, the terminal 1009 may select a radio resource again after a predetermined time and attempt transmission (S1025). The predetermined time information for the data retransmission of the terminal 1009 may be included in the direct communication setting information between terminals or may be a value preset in the terminal.

The terminal 1009 can confirm whether or not the trigger condition is satisfied when the direct communication data transmission / reception between the terminals fails. For example, transmission of information related to a direct communication failure between terminals may be performed when a data transmission attempt fails more than a predetermined number of times, when a transmission attempt fails for a predetermined time, when a periodic report is made, Lt; / RTI > may be triggered in either case.

The terminal 1009 may transmit the information to the base station 1001 when the transmission of the information related to the direct communication failure between terminals is triggered (S1040). Information related to the direct communication failure between the terminals may be included in the above-described direct communication status report between the terminals.

For example, information related to direct communication failure between terminals may include the following information.

- Number of unsuccessful attempt of direct communication data transmission between terminals: It may include information related to the set time from the base station or the number of unsuccessful attempts of data transmission for a preset time.

- Duration of direct communication data transmission attempt between terminals: Duration information may include period information after the first failure of the direct communication data transmission attempt between terminals to the present, or period information from the first failure to just before the first success.

- Location information of the terminal: It may include the current location information of the terminal. The current location information of the terminal can be obtained from a positioning system such as GPS or GNSS. In addition, the serving cell and / or neighbor cell measurement information measured by the terminal may be included.

- Identification information of the direct communication group between the terminals to which the terminal belongs: It may include identification information used by the terminal for communication of the direct communication group between the terminals with which the terminal is communicating. In one example, the identification information may be a specific value used to distinguish the group, such as an identifier or an index.

- Data amount for direct communication transmission between terminals: Buffer information related to direct communication between terminals can be included.

The base station 1001 can perform reallocation of radio resources or change and allocate radio resources based on the information related to the received direct communication failure between terminals.

As described above, according to the present invention, a base station can efficiently allocate radio resources by receiving an inter-terminal communication status report received from a terminal. That is, the base station can allocate radio resources for inter-terminal communication based on the necessity of direct communication between terminals and status information which are performed within its coverage. Therefore, the base station can efficiently allocate and manage radio resources. In addition, in the case of the terminal, the radio resources necessary for the inter-terminal communication are correctly allocated, thereby increasing the success rate of direct communication between the terminals.

Hereinafter, operations of the terminal and the base station will be described with reference to the drawings when all the embodiments of the present invention described above are performed.

11 is a flowchart illustrating an operation of a terminal according to another embodiment of the present invention.

A method for transmitting a direct communication status report between terminals in a terminal according to another embodiment of the present invention includes receiving a first signal including direct communication setting information between terminals from a base station or a radio resource allocation entity, Determining a trigger of the direct communication status report based on the information and transmitting a second signal including the direct communication status report between the base station and the radio resource allocation entity.

Referring to FIG. 11, a UE receives a first signal from a BS or a radio resource allocation entity (S1110). The first signal may include direct communication setting information between terminals. For example, the first signal may include radio resource allocation information necessary for a terminal to perform direct communication between terminals, and may include configuration information for reporting a direct communication state between terminals. Additionally, the first signal may include the discovery message transmission establishment information described above.

Also, the first signal may be received with SIB or higher layer signaling. For example, the upper layer signaling may be an RRC signaling.

The terminal may attempt direct communication between the terminals by receiving the first signal. That is, the terminal may transmit a discovery message for direct communication between terminals and may transmit data.

The terminal can monitor the trigger of the inter-terminal direct communication status report based on the trigger condition information (S1120). As described above, the trigger condition can be received in the first signal. Or may be preset in the terminal. Or the satisfaction of the trigger condition may be determined according to whether or not the request message is received from the base station.

If the MS satisfies the trigger condition, the MS may transmit a second signal including the inter-terminal communication status report to the BS or the RR assignment entity (S1130). As described above, the terminal can transmit the second signal according to whether the communication between the terminals is successful, whether the discovery message is failed or the data transmission is unsuccessful. The second signal may include information related to the inter-terminal communication as shown in FIG. Or information related to discovery failure or information related to direct communication failure between terminals as in the case of the second and third embodiments. Or all three types of information, or at least two or more pieces of information.

The above-described radio resource allocation entity may include a base station. The radio resource allocation entity may include an entity that performs at least one of functions of managing a terminal group performing radio resource allocation, sink channel transmission, and direct communication between terminals for direct communication between terminals It can mean.

12 is a flowchart illustrating an operation of a base station according to another embodiment of the present invention.

A method for receiving a direct communication status report between terminals in a base station according to another embodiment of the present invention includes generating a first signal including direct communication setting information between terminals and transmitting a first signal to a terminal And receiving a second signal including a direct communication status report from the terminal to the terminal.

Referring to FIG. 12, a BS may generate a first signal including direct-to-UE communication setup information for transmitting to a mobile station (S1210). For example, the first signal may include radio resource allocation information necessary for a terminal to perform direct communication between terminals, and may include configuration information for reporting a direct communication state between terminals. Additionally, the first signal may include the discovery message transmission establishment information described above.

The base station transmits the generated first signal to the terminal (S1220). As an example, the first signal may be sent in SIB or higher layer signaling. The higher layer signaling may also be an RRC signaling.

The base station can receive the second signal when the inter-terminal communication status report of the terminal is triggered (S1230). The base station can transmit the trigger condition information included in the first signal. Or may transmit a request message requesting transmission of a direct communication status report between terminals to the terminal. When the MS receives the request message, it can determine that the trigger condition is satisfied and transmit the second signal.

The second signal may include various information depending on the success of the inter-terminal communication or whether the discovery message transmission / reception fails or the data transmission failure. For example, the second signal may include information related to end-to-end communication as shown in FIG. Or information related to discovery failure or information related to direct communication failure between terminals as in the case of the second and third embodiments. Or all three types of information, or at least two or more pieces of information.

The base station can determine a radio resource allocation by receiving a second signal including the inter-terminal direct communication status report. Or the base station may determine a change in the allocated radio resource.

The terminal and the base station can perform all the embodiments of the present invention through the operations described above.

13 is a diagram illustrating a configuration of a terminal according to another embodiment of the present invention.

A terminal 1300 according to another embodiment of the present invention includes a receiving unit 1330 that receives a first signal including direct communication setting information between terminals from a base station or a radio resource allocation entity, A controller 1310 for confirming a trigger of the communication status report, and a transmitter 1320 for transmitting a second signal including a direct communication status report between terminals to the base station or the radio resource allocation entity.

Specifically, the controller 1310 controls the overall operation of the terminal necessary to confirm and transmit the trigger of the inter-terminal direct communication status report necessary for carrying out the present invention described above. For example, the control unit 1310 can confirm whether the direct communication status report is triggered based on the trigger condition information received from the base station or preset in the terminal. In addition, the control unit 1310 can control an operation for performing direct communication between the target terminal and the terminal.

The transmitter 1320 can transmit the second signal to the base station or the radio resource allocation entity when the inter-terminal direct communication status report is triggered. The inter-terminal direct communication status report included in the second signal may include various information according to each embodiment described above. For example, the second signal may include information related to end-to-end communication as shown in FIG. Or information related to discovery failure or information related to direct communication failure between terminals as in the case of the second and third embodiments. Or all three types of information, or at least two or more pieces of information. In addition, the transmitter 1320 may transmit data and signals through direct communication between the target terminal and the terminal.

The receiving unit 1330 receives the first signal including the direct communication setting information from the base station or the radio resource allocation entity. For example, the first signal received by the receiver 1330 may include radio resource allocation information necessary for the terminal to perform direct communication between the terminals, and may include setting information for direct communication status reporting between the terminals It is possible. Additionally, the first signal may include the discovery message transmission establishment information described above. Also, the first signal may be received with SIB or higher layer signaling. For example, the upper layer signaling may be an RRC signaling.

In addition, the transmitting unit 1320 and the receiving unit 1330 are used to transmit and receive signals, messages, and data necessary for carrying out the present invention to the base station or the target terminal.

14 is a diagram illustrating a configuration of a base station according to another embodiment of the present invention.

The base station 1400 according to another embodiment of the present invention includes a controller 1410 for generating a first signal including direct communication setting information between terminals, a transmitter 1420 for transmitting the first signal to the terminal, And a receiving unit 1430 for receiving a second signal including an inter-direct communication status report.

Specifically, the controller 1410 generates and transmits the inter-terminal communication setup information to be transmitted to the terminal, receives the inter-terminal communication status report from the terminal, and controls the overall operation of the base station necessary for allocating the radio resources. For example, the control unit 1410 can generate the inter-terminal communication setting information. The first signal may include radio resource allocation information necessary for a UE to perform direct communication between terminals, and may include configuration information for direct communication status reporting between terminals. Additionally, the first signal may include the discovery message transmission establishment information described above.

In addition, the controller 1410 can control operations related to radio resource allocation for direct communication between terminals. For example, wireless resources may be allocated or changed based on a direct communication status report between terminals.

The transmitter 1420 can transmit the generated first signal to the terminal. The first signal may be sent in SIB or higher layer signaling.

The receiver 1430 can receive a second signal including a direct communication status report from the terminal. For example, the second signal may include various information depending on the success of the inter-terminal communication, whether the discovery message transmission / reception is failed, or the data transmission failure. Specifically, the second signal may include information related to the inter-terminal communication as shown in Fig. Or information related to discovery failure or information related to direct communication failure between terminals as in the case of the second and third embodiments. Or all three types of information, or at least two or more pieces of information.

In addition, the transmitting unit 1420 and the receiving unit 1430 are used to transmit and receive signals, messages, and data necessary for carrying out the present invention to and from the terminal.

The foregoing description is merely illustrative of the technical idea of the present invention, and various changes and modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents should be construed as falling within the scope of the present invention.

Claims (20)

A method for a terminal to transmit a direct communication status report between terminals,
Receiving a first signal including direct-to-terminal communication setup information from a base station or a radio resource allocation entity;
Confirming a trigger of the inter-terminal direct communication status report based on trigger condition information; And
And transmitting a second signal including the inter-terminal direct communication status report to the base station or the radio resource allocation entity. The method according to claim 1,
The direct-to-terminal direct communication setting information includes:
And information on at least one of radio resource allocation information for direct communication between terminals and direct communication status report setting information between terminals. The method according to claim 1,
Wherein the first signal comprises:
A system information block (SIB) or a higher layer signaling. The method according to claim 1,
The trigger condition information includes:
Or included in the first signal or preset in the terminal. The method according to claim 1,
The inter-terminal direct communication status report includes:
Information relating to discovery failure for direct communication between terminals or information on direct communication failure between terminals. The method according to claim 1,
Wherein the radio resource allocation entity comprises:
And managing the terminal group performing radio resource allocation, sink channel transmission, and direct communication between the terminals for direct communication between the terminals. A method for a base station to receive a direct communication status report between terminals,
The method comprising: generating a first signal including direct-to-terminal direct communication setting information;
Transmitting the first signal to a terminal; And
And receiving a second signal from the terminal, the second signal comprising the inter-terminal direct communication status report. 8. The method of claim 7,
The direct-to-terminal direct communication setting information includes:
And information on at least one of radio resource allocation information for direct communication between terminals and direct communication status report setting information between terminals. 8. The method of claim 7,
Wherein the first signal comprises:
A method transmitted in a system information block (SIB) or upper layer signaling. 8. The method of claim 7,
The inter-terminal direct communication status report includes:
Information relating to discovery failure for direct communication between terminals or information on direct communication failure between terminals. A terminal for transmitting a direct communication status report between terminals,
A receiving unit for receiving a first signal including direct communication setting information from a base station or a radio resource allocation entity;
A controller for confirming a trigger of the inter-terminal direct communication status report based on the trigger condition information; And
And a transmitter for transmitting a second signal including the inter-terminal direct communication status report to the base station or the radio resource allocation entity. 12. The method of claim 11,
The direct-to-terminal direct communication setting information includes:
Wherein the terminal includes at least one of radio resource allocation information for direct communication between terminals and direct communication status report setting information between terminals. 12. The method of claim 11,
Wherein the first signal comprises:
A terminal received in a system information block (SIB) or higher layer signaling. 12. The method of claim 11,
Wherein,
And confirms the trigger of the inter-terminal direct communication status report based on the trigger condition information included in the first signal or preset in the terminal. 12. The method of claim 11,
The inter-terminal direct communication status report includes:
Information related to the discovery failure for the direct communication between the terminals or the information about the direct communication failure between the terminals. 12. The method of claim 11,
Wherein the radio resource allocation entity comprises:
Wherein the terminal is an entity performing at least one of a function of allocating a radio resource for direct communication among the terminals, a sink channel transmission, and a function of managing a terminal group performing direct communication between the terminals. A base station for receiving a direct communication status report between terminals,
A control unit for generating a first signal including direct-to-terminal direct communication setting information;
A transmitter for transmitting the first signal to a terminal; And
And a receiver for receiving a second signal including the inter-terminal direct communication status report from the terminal. 18. The method of claim 17,
The direct-to-terminal direct communication setting information includes:
Wherein the base station includes at least one of radio resource allocation information for direct communication between terminals and direct communication status report setting information between terminals. 18. The method of claim 17,
Wherein the first signal comprises:
A base station transmitted in a system information block (SIB) or upper layer signaling. 18. The method of claim 17,
The inter-terminal direct communication status report includes:
Information relating to discovery failure for direct communication between terminals or information on direct communication failure between terminals.

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