KR20160037037A - Method and apparatus for resource control in wireless communication system supporting device to device communication - Google Patents

Abstract

The present invention relates to a method and a device for resource control in a wireless communication system supporting D2D communication. The D2D communication method according to the present invention includes: a step of determining a T-PRT index for D2D communication; a step of determining a T-PRT indicated by the T-PRT index based on sub-frame bundling setting; a step of generating a D2D SA including the T-RPT index and a sub-frame bundling indicator indicating the sub-frame bundling setting; a step of transmitting the generated D2D SA to a D2D Rx terminal; and a step of mapping D2D data on sub-frames indicated by the T-RPT to transmit the mapped D2D data to the D2D Rx terminal. According to the present invention, an impact of a collision between WAN communication and D2D communication can be reduced, and thus D2D communication transmission efficiency can be enhanced.

Description

TECHNICAL FIELD [0001] The present invention relates to a method and apparatus for controlling resources in a wireless communication system supporting inter-

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to wireless communication, and more particularly, to a method and apparatus for controlling resources in a wireless communication system supporting device to device (D2D) communication.

D2D communication in a wireless communication system is a communication method in which terminals close to each other in geographical proximity use transmission and reception techniques of the wireless communication system in the frequency band of the wireless communication system or other bands but communicate directly with each other without going through an infrastructure such as a base station . This provides the advantage that the terminal can use the wireless communication in an area other than the area where the wireless communication infrastructure is constructed and reduce the network load of the wireless communication system.

In D2D communication, a Resource Pattern for Transmission (RPT) may be used. In the time domain, RPT can be called T (Time domain) -RPT and can be defined in units of subframes. Since the transmission of the D2D signal and the WAN signal can be performed in the same frequency domain (e.g., subcarrier) and time domain (e.g., subframe), since the D2D communication can be performed on the license band of wide area network The performance may be reduced due to interference, or the transmission of the D2D signal may not be performed in the corresponding interval in order to avoid this.

Therefore, RPT of D2D communication should be defined to reduce the possibility of collision and increase transmission efficiency, and a criterion and operation method of applying RPT of D2D communication are needed.

SUMMARY OF THE INVENTION The present invention provides a method and apparatus for resource control in a wireless communication system supporting D2D communication.

Another object of the present invention is to define a resource pattern for D2D communication in a wireless communication system supporting D2D communication.

Another object of the present invention is to provide a terminal and a base station for controlling D2D communication resource allocation in a wireless communication system supporting D2D communication.

A further technical object of the present invention is to provide a criterion for determining an RPT for D2D communication in a wireless communication system supporting D2D communication.

Another aspect of the present invention is to provide an RPT control method and apparatus for D2D communication for a terminal in which subframe bundling is established.

According to an aspect of the present invention, there is provided a method of controlling D2D resource setting by a base station in a wireless communication system supporting a device to device (D2D) communication. The method includes the steps of: determining a T-RPT type for the D2D Tx terminal based on whether sub-frame bundling is set in the D2D Tx terminal, determining a T-RPT type based on the determined T-RPT type Determining a T-PRT index for a D2D Tx terminal, generating a D2D grant including the T-RPT index, and transmitting the generated D2D grant to the D2D Tx terminal. do.

According to another aspect of the present invention, there is provided a D2D communication method performed by a D2D Tx terminal in a wireless communication system supporting a device to device (D2D) communication. The method includes determining a T-PRT index for D2D communication, determining a T-PRT indicated by a T-PRT index based on whether or not sub-frame bundling is set up, Generating a D2D SA (Scheduling Assingment) including a sub-frame bundling indicator indicating whether to set frame bundling and a T-RPT index, transmitting the generated D2D SA to a D2D Rx terminal, And mapping the D2D data to the D2D Rx terminal.

According to another aspect of the present invention, there is provided a D2D communication method performed by a D2D Rx terminal in a wireless communication system supporting a device to device (D2D) communication. The method includes receiving a D2D SA (Scheduling Assignment) including a sub-frame bundling indicator and a time domain-resource pattern for transmission (T-RPT) index from a D2D Tx terminal on a D2D SA receiving resource pool, Determining whether or not sub-frame bundling is set in the D2D Tx terminal based on whether the T-RPT index indicates a T-RPT index based on whether the sub-frame bundling is set up; And receiving D2D data from the D2D Tx terminal on the subframes.

According to the present invention, it is possible to reduce the influence of the collision between the WAN communication and the D2D communication, thereby increasing the transmission efficiency of the D2D communication.

According to the present invention, when the normal HARQ operation is set to the Tx terminal, the T-PRT type is applied. When the sub-frame bundling is set, the changed T-RPT type is applied. -RPT type can be applied.

Also, according to the present invention, it is possible to efficiently designate T-PRT using a T-RPT index having a smaller length than that of the changed T-RPT type.

1 is a block diagram illustrating a wireless communication system.
2 is a diagram for explaining the concept of a cellular network-based D2D communication applied to the present invention.
3 is a diagram for illustrating an exemplary D2D resource pool setting in the time domain.
4 is a diagram for explaining a sub-frame indication according to a T-RPT bitmap.
5 is a diagram for explaining the concept of subframe bundling.
FIG. 6 is a diagram for explaining a T-RPT design when an FDD and a normal HARQ operation are set in the UE.
7 is a diagram for explaining a T-RPT design when a TDD UL / DL configuration 0 and a normal HARQ operation are set in the UE.
8 is a view for explaining a T-RPT design when TDD UL / DL configuration 1 and normal HARQ operation are set in the UE.
FIG. 9 is a diagram for explaining a T-RPT design when the TDD UL / DL configuration 6 and the normal HARQ operation are set in the UE.
FIGS. 10-13 illustrate examples of T-RPT designs for terminals with server frame bundling established.
FIG. 14 exemplarily shows a flowchart of a base station that performs resource control for D2D communication.
15 shows a D2D Tx terminal flow diagram for performing D2D communication.
FIG. 16 exemplarily shows a flowchart of a D2D Rx terminal performing D2D communication.
17 is a block diagram illustrating a base station, a D2D Tx terminal, and a D2D Rx terminal according to an embodiment of the present invention.

Hereinafter, the contents related to the present invention will be described in detail with reference to exemplary drawings and embodiments, together with the contents of the present invention. 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 symbols as possible even if they are shown in different drawings. In the following description of the embodiments 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 disclosure rather unclear.

In addition, the present invention will be described with respect to a wireless communication network. The work performed in the wireless communication network may be performed in a process of controlling a network and transmitting data by a system (e.g., a base station) Work can be done at a terminal included in the network.

1 is a block diagram illustrating a wireless communication system. This may be a network structure of an Evolved-Universal Mobile Telecommunications System (E-UMTS). The E-UMTS system may include LTE (Long Term Evolution) and LTE-A (advanced) systems. Wireless communication systems are widely deployed to provide various communication services such as voice, packet data, and the like. In addition, the wireless communication system may support device to device (D2D) communication between the terminal and the terminal. A wireless communication system supporting D2D communication will be described later.

On the other hand, there is no limitation on a multiple access technique applied to a wireless communication system. (CDMA), Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Orthogonal Frequency Division Multiple Access (OFDMA), Single Carrier FDMA , OFDM-CDMA, and the like.

Here, TDD (Time Division Duplex) scheme in which uplink and downlink transmission are transmitted using different time periods or FDD (Frequency Division Duplex) scheme in which they are transmitted using different frequencies may be used .

Referring to FIG. 1, an E-UTRAN includes at least one base station (BS) 20 that provides a control plane and a user plane to a UE. A user equipment (UE) 10 may be fixed or mobile and may be a mobile station, an AMS (advanced MS), a user terminal (UT), a subscriber station (SS) It can be called a term.

The base station 20 generally refers to a station that communicates with the terminal 10 and includes an evolved Node B (eNodeB), a base transceiver system (BTS), an access point, a femto-eNB ), A pico-eNB, a home eNB, a relay, and the like. The base station 20 may provide at least one cell to the terminal. The cell may mean a geographical area where the base station 20 provides communication services, or may refer to a specific frequency band. A cell may denote a downlink frequency resource and an uplink frequency resource. Or a cell may mean a combination of a downlink frequency resource and an optional uplink frequency resource. Also, in general, when a carrier aggregation (CA) is not considered, uplink and downlink frequency resources always exist in one cell.

An interface for transmitting user traffic or control traffic may be used between the base stations 20. The source BS 21 refers to a base station for which a radio bearer is currently set with the UE 10 and a target BS 22 transmits a radio bearer to the source BS 21, Means a base station to perform a handover in order to set up a radio bearer.

The base stations 20 may be connected to each other via the X2 interface, which is used to exchange messages between the base stations 20. [ The base station 20 is connected to an Evolved Packet System (EPS), more specifically an MME (Mobility Management Entity) / S-GW (Serving Gateway) 30 via an S1 interface. S1 interface supports many-to-many-relations between the base station 20 and the MME / S-GW 30. The PDN-GW 40 is used to provide packet data service to the MME / S-GW 30. The PDN-GW 40 is changed depending on the purpose of communication or the service, and the PDN-GW 40 supporting the specific service can be found using APN (Access Point Name) information.

The Inter E-UTRAN handover is a basic handover mechanism used for handover between E-UTRAN access networks, and consists of an X2-based handover and an S1-based handover. X2-based handover is used when the UE desires to perform handover from the source BS 21 to the target BS 22 using the X2 interface. At this time, the MME / S-GW 30 is not changed Do not.

The first bearer set between the P-GW 40, the MME / S-GW 30, the source base station 21 and the terminal 10 is released by the S1-based handover, A new second bearer is established between the GW 40, the MME / S-GW 30, the target base station 22 and the terminal 10. [

Hereinafter, downlink refers to communication from the base station 20 to the terminal 10, and uplink refers to communication from the terminal 10 to the base station 20. The downlink is also referred to as a forward link, and the uplink is also referred to as a reverse link. In the downlink, the transmitter may be part of the base station 20, and the receiver may be part of the terminal 10. [ In the uplink, the transmitter may be part of the terminal 10, and the receiver may be part of the base station 20.

Meanwhile, the wireless communication system can be divided into a radio protocol architecture for a user plane and a wireless protocol structure for a control plane. The data plane is a protocol stack for transmitting user data, and the control plane is a protocol stack for transmitting control signals.

The physical layer (PHY (physical layer) provides an information transfer service to an upper layer using a physical channel. The physical layer is connected to a medium access control (MAC) layer, which is an upper layer, through a transport channel. Data is transferred between the MAC layer and the physical layer through the transport channel. The transport channel is classified according to how the data is transmitted through the air interface. Data is transferred between the different physical layers, that is, between the transmitter and the physical layer of the receiver through a physical channel. There are several physical control channels. The physical downlink control channel (PDCCH) informs the UE of resource allocation of a paging channel (PCH), a downlink shared channel (DL-SCH), and hybrid automatic repeat request (HARQ) information related to the DL-SCH. The PDCCH may carry an uplink scheduling grant informing the UE of the resource allocation of the uplink transmission. A physical control format indicator channel (PCFICH) informs the UE of the number of OFDM symbols used for PDCCHs and is transmitted every subframe. PHICH (Physical Hybrid ARQ Indicator Channel) carries HARQ ACK / NAK signal in response to uplink transmission. A physical uplink control channel (PUCCH) carries uplink control information such as HARQ ACK / NAK, scheduling request and CQI for downlink transmission. A physical uplink shared channel (PUSCH) carries an uplink shared channel (UL-SCH).

The function of the MAC layer includes a mapping between a logical channel and a transport channel and a multiplexing / demultiplexing into a transport block provided as a physical channel on a transport channel of a MAC SDU (service data unit) belonging to a logical channel. The MAC layer provides a service to a Radio Link Control (RLC) layer through a logical channel. The logical channel can be divided into a control channel for transferring control area information and a traffic channel for transferring user area information.

The function of the RLC layer includes concatenation, segmentation and reassembly of the RLC SDUs. The RLC layer includes a Transparent Mode (TM), an Unacknowledged Mode (UM), and an Acknowledged Mode (RB) in order to guarantee various QoSs required by a radio bearer (RB) , And AM). AM RLC provides error correction via automatic repeat request (ARQ).

The functions of the Packet Data Convergence Protocol (PDCP) layer in the user plane include transmission of user data, header compression and ciphering. The function of the Packet Data Convergence Protocol (PDCP) layer in the user plane includes transmission of control plane data and encryption / integrity protection.

The RRC layer is responsible for the control of logical channels, transport channels and physical channels in connection with the configuration, re-configuration and release of radio bearers. RB means a logical path provided by a first layer (PHY layer) and a second layer (MAC layer, RLC layer, PDCP layer) for data transmission between a UE and a network. The setting of the RB means a process of defining characteristics of a radio protocol layer and a channel to provide a specific service, and setting each specific parameter and an operation method. RB may be divided into SRB (Signaling RB), DRB (Data RB), and MRB (MBMS PTM RB). The SRB is used as a path for transmitting the RRC message in the control plane, and the DRB is used as a path for transmitting the user data in the user plane. The MRB is used as a path for transmitting Multimedia Broadcast Multicast Service (MBMS) data.

The non-access stratum (NAS) layer located at the top of the RRC layer performs functions such as session management and mobility management.

2 is a diagram for explaining the concept of a cellular network-based D2D communication applied to the present invention.

D2D communication may mean a technique of directly transmitting and receiving data between terminals. Hereinafter, it is assumed that the terminal supports D2D communication in the embodiment of the present invention. A terminal supporting D2D communication performs D2D communication when a user of the terminal sets a switch to enable (enable) D2D communication through the operation of a user interface (UI) . Or a configuration in which D2D communication is always possible depending on the characteristics of the terminal (for example, a terminal manufactured for public purposes) or a subscriber policy (for example, a public safety plan, etc.).

Or, a D2D server that manages a ProSe (Proximity Services) ID and a ProSe application ID of a terminal using D2D communication, a serving base station of the terminal, etc.) of a network (for example, It is possible to finally determine whether or not the D2D communication can be performed by the terminal set to be D2D communication. That is, even if the terminal is set to enable D2D communication by the user of the terminal, D2D communication may be performed only when D2D communication is permitted by the network. Information on whether or not D2D communication is possible can be displayed on the screen of the terminal.

The resources for D2D communication may be allocated by a terminal (hereinafter, cluster head) or a base station that is responsible for allocating resources for D2D communication in D2D communication. In this case, the terminal must transmit a BSR (Buffer State Report) for the D2D data to the base station or the cluster head when performing D2D communication. Hereinafter, the base station and the cluster head are collectively referred to as a base station for convenience of explanation.

Recently, there have been attempts to perform discovery and direct communication between devices in network coverage (out-coverage) or out-of-coverage for the purpose of public safety Research. A terminal transmitting a signal based on inter-terminal communication may be referred to as a transmission terminal (Tx UE), and a terminal receiving a signal based on inter-terminal communication may be defined as a reception terminal (Rx UE). The transmitting terminal may transmit a discovery signal, and the receiving terminal may receive a discovery signal. The roles of the transmitting terminal and the receiving terminal may be changed. On the other hand, the signal transmitted by the transmitting terminal may be received by two or more receiving terminals.

When terminals in close proximity in a cellular system perform D2D communication, the load of the base station can be dispersed. Also, when neighboring terminals perform D2D communication, terminals transmit data at a relatively short distance, so that transmission power consumption and latency of the terminal can be reduced. In addition, since the WAN communication and the D2D communication use the same resources, the frequency utilization efficiency can be improved. Herein, WAN communication may mean to provide wide coverage in a cellular network to provide voice / data traffic to mobile terminals, and WAN communication may include WCDMA, LTE, Wimax, and the like.

D2D communication can be classified into a communication method of a terminal located in an in-coverage of a network coverage (base station coverage) and a communication method of a terminal located out-of-coverage of a network. Also, D2D can be replaced with proximity based service (ProSe) or ProSe-D2D or ProSe. The use of the term ProSe for D2D means that the meaning of the proximity-based service can be added to the meaning of the inter-terminal communication instead of changing the meaning of the technology for directly transmitting and receiving data between the terminals.

2, communication between the first terminal 210 located in the first cell and the second terminal 220 located in the second cell, communication between the third terminal 230 located in the first cell and the third terminal located in the first cluster 210, 4 terminal 240 may be a D2D communication within the network coverage. The communication between the fourth terminal 240 located in the first cluster and the fifth terminal 250 located in the first cluster may be D2D communication outside the network coverage. Here, the fifth terminal 250 may operate as a cluster head (CH) of the first cluster. Here, the cluster head means a terminal that is responsible for allocating resources. The cluster header may include an independent synchronization source (ISS) for synchronization of Out-of-coverage terminals.

An Access Stratum (AS) signaling is not used in order to configure a ProSe ID to which the terminal is allocated for D2D communication, and the ProSe ID is communicated through an upper level application level or an authentication server for D2D communication Can be assigned. Here, the ProSe ID can be used only for D2D communication, which is distinguished from the ProSe ID configured for D2D discovery. In addition, the ProSe ID assigned for the D2D communication may be configured separately from the ProSe ID for the group and the ProSe ID only for the corresponding terminal. A single terminal may be included in a plurality of groups (for example, 5 to 6 groups may be included), and a ProSe ID for each group may be configured. That is, a plurality of ProSe IDs can be configured for a single terminal. The ProSe ID for the group may be composed of a group ID, and the group ID may be redefined for each layer. Or a group ID for each layer may be configured through an upper layer. Alternatively, the ProSe ID may be defined as a value including both the ID for the group and the ID information for only the corresponding terminal. That is, when the terminal performs the authentication procedure with the D2D server for D2D communication, the D2D server assigns ProSe IDs as many as the number of groups to which the terminal belongs, but the corresponding terminal ID information included in each ProSe ID is all the same , And only the group ID information may be different.

D2D communication can be divided into a search procedure for performing discovery for communication between terminals and a direct communication procedure for transmitting and receiving control information and / or traffic data between terminals. D2D communication can be used for various purposes. For example, D2D communications within network coverage can be used for public safety, ultra-low latency services, and commercial-grade services. D2D communications outside network coverage can be used only for public safety.

As one embodiment of performing D2D communication, the base station 200 may transmit D2D resource allocation information to the first terminal 210. [ The first terminal 210 is a terminal located within the coverage of the base station 200. The D2D resource allocation information may include allocation information for a transmission resource and / or a reception resource that can be used for D2D communication between the first terminal 210 and another terminal (e.g., the second terminal 220) .

The first terminal 210 receiving the D2D resource allocation information from the base station can transmit the D2D resource allocation information to the second terminal 220. [ The second terminal 220 may be a terminal located outside the coverage of the base station 200. The first terminal 210 and the second terminal 220 can perform D2D communication based on the D2D resource allocation information. Specifically, the second terminal 220 can acquire information on the D2D communication resources of the first terminal 210. [ The second terminal 220 can receive data transmitted from the first terminal 210 through the resource indicated by the information on the D2D communication resource of the first terminal 210. [

In D2D communication, a terminal can transmit physical layer control data to another terminal. However, a separate channel (for example, a physical uplink control channel (PUCCH)) for transmitting physical layer control data in D2D communication may not be defined. If the physical layer control channel is not defined in the D2D communication, the terminal can use various methods to transmit control data for D2D communication.

Here, the physical layer control information for synchronization in the D2D communication includes information transmitted through a synchronization channel, and may be provided through a PD2 DSCH (Physical D2D Synchronization CHannel) channel, for example. The physical layer control channel (SA channel) including the physical layer control information for data communication includes Scheduling Assignment (SA) information, a ProSe dedicated physical channel similar to the PUSCH format for D2D communication, But the parameters may be provided over a different channel than the physical channel for WAN (Wide Area Network) transmission. Actual traffic data distinguished from physical layer control information in D2D communication can be expressed by the term " D2D data ".

At the perspective of the transmitting terminal (Tx UE), the transmitting terminal may operate in two modes with respect to resource allocation for D2D communication.

Mode 1 is the case where a base station or a relay node (hereinafter referred to as a base station, which may include a relay node) schedules certain resource (s) for D2D communication. That is, in mode 1, the specific resource (s) used for transmitting the D2D data and the D2D control information of the transmitting terminal is designated by the base station. While mode 2 is the case where the terminal is set by the base station or selects the specific resource (s) directly from the predetermined resource pool. That is, in mode 2, the Tx terminal directly selects specific resource (s) for transmission of D2D data and D2D control information.

A D2D capable terminal supports at least mode 1 or 2 for in-coverage D2D communication. A D2D capable terminal supports mode 2 for at least out-of-coverage or edge-of-coverage D2D communication.

In Mode 1, the location of the resource (s) for transmission of the D2D control information and the location of the resource (s) for transmission of the D2D data is given by the base station. That is, for the D2D SA and the data transmission, the same grant is given to the UE by transmitting the (E) PDCCH from the base station to the DCI message format having the same size as DCI format 0.

In Mode 2, the resource pool for the transmission of D2D control information may be pre-configured and / or semi-statically configured by the base station. In this case, the Tx UE can select a resource for transmitting D2D control information in the resource pool for transmission of D2D control information.

D2D discovery is performed on the D2D discovery resource. For example, the D2D terminal may communicate with each other through discovery resources (hereinafter referred to as D2D discovery resources) randomly selected (other than network coverage) or set by the base station (within network coverage) within each discovery period A discovery signal can be transmitted. In the case of random resource selection, the transmission of the discovery signal is based on a fixed or adaptive transmission probability from a pre-configured or configured nominal transmission probability. May determine the resources for the user. The definition of the detection interval can be classified according to the detection type 1 and the detection type 2B. For Type 1, the discovery interval represents a pool of resources allocated for sending / receiving D2D discovery signals in the cell. For Type 2B, the discovery interval represents a pool of resources for sending / receiving the D2D discovery signal from the cell. In Type 2B, to transmit a D2D discovery signal, a specific resource can be indicated in the resource pool for transmission and reception in the network.

The resource pool configuration according to D2D mode / type can be shown as the following table.

mode / type resource pool D2D communication mode 1 SA: Rx resource pool
D2D data: X mode 2 SA: Tx / Rx resource pool
D2D data: Tx / Rx resource pool D2D discovery
type 1 Tx / Rx resource pool type 2B Rx resource pool

Referring to Table 1, in Mode 1, a resource pool is set for SA reception. In Mode 1, resource pools for separate transmission are not needed for SA transmission and data transmission because a specific resource is scheduled by (E) PDCCH that transmits a D2D grant by a base station. In mode 2, a resource pool is set for transmission / reception of SA, and a resource pool is set for data transmission / reception.

On the other hand, in the case of Type 2B, the transmission of the discovery signal is controlled on the network as a resource setting, and a transmission resource pool is additionally set in the receiving resource pool for its time / frequency hopping. On the other hand, in the case of Type 1, since the transmission of the discovery signal is not controlled by the network, all resource pools for transmitting and receiving the discovery signal are set.

For example, a resource pool in a cell for SA, discovery signal, and mode 2 data transmission and reception may be indicated based on the following parameters.

The period value ("period") parameter indicates a period in which the D2D resource pool appears in the time domain. In this period, not only the serving cell but also the resource pool of the neighboring cell can be represented. The value can be assumed to be a cell-specific value with the same setting value in all cells and can have a different range of values according to the FDD / TDD UL-DL setting. For example, FDD and TDD UL-DL settings 1 through 5 have values of {40, 80, 160, 320 ms} while other TDD UL-DL settings 0 and 6 have values of {80, 160, 320 ms} It can have a range of values. In addition, the range of values may vary depending on the D2D physical channel. In particular, the period value associated with the discovery signal resource pool tends to have a period value greater than the resource pool (e.g., SA, mode 2) associated with the D2D data communication. As an example, the period value associated with the discovery signal resource pool may have 320, 640, 1280, 2560, 5120, 10240 ms.

The subframe bitmap parameter represents a D2D resource pool in the time domain and may be composed of a plurality of bit strings corresponding to the subframes and may have a length of different bit strings according to the FDD / TDD UL-DL configuration Lt; / RTI > For example, if a certain bit value of the bit string is 1, it indicates that the corresponding subframe is a subframe for the D2D resource pool, and if the bit value is 0, the corresponding subframe is not a subframe for the D2D resource pool .

The initial offset indicator ("offsetIndicatorInitialization") parameter is used to determine the start of the resource pool. For example, the offset granularity unit may be defined as 1 ms, 10 ms, or the length of a subframe bitmap. The initial offset indicator can be indicated using two offsets. (Network options and configures to UE about a signal of the discoveryOffsetIndicator using 2 offsets. If the network chooses to discoveryOffsetIndicator using 2 offsets, the granularity of one of the two offsets does not need to be 1 subframe).

The PRB length ("prbLength") parameter indicates a resource pool allocation length of a physical resource block (PRB) in the frequency domain.

The PRB start ("staRPTRB") parameter indicates the PRB index at which the resource pool in the frequency domain begins. For example, the resource pool in the frequency domain may include PRBs that are equal to or greater than the PRB index indicated by staRPTRB and equal to or less than the PRB index indicated by staRPTRB + prbLength.

The PRB termination ("endPRB") parameter indicates the PRB index at which the resource pool in the frequency domain terminates. For example, in the frequency domain, the resource pool may contain PRBs that are equal to or less than the PRB index indicated by endPRB and equal to or greater than the PRB index indicated by endPRB - prbLength.

Subframe bitmap "parameter used to indicate a discovery signal resource pool with a parameter corresponding to the discovery signal.

As such, SAs, discovery signals, and resource pools within a cell for Mode 2 data transmission and reception may be indicated based on the parameters described above, and in detail, each D2D channel may have different parameter values and application methods .

3 is a diagram for illustrating an exemplary D2D resource pool setting in the time domain. FIG. 3 shows a resource pool setting in mode 2.

Referring to FIG. 3, an SA / data interval of mode 2 includes one SA resource pool and n data resource pools. That is, for mode 2, the SA resource pool is repeated once in the SA / data period and the data resource pool is repeated n times. In this case, the starting point of the SA resource pool can be indicated by the SA offset, and the starting point of the data pool can be indicated by the data offset. Information about the location of the resource pool can be indicated utilizing the above parameters. One subframe bitmap parameter for indicating a data resource pool may be repeatedly applied n times to indicate one data resource pool. For example, if one subframe bitmap parameter for indicating a data resource pool indicates "1010" and n is 2, then a " 1010 " . As a result, various parameters described previously can be used to indicate a pool of resources.

The subframe bitmap may be applied differently depending on the FDD / TDD configuration. For FDD, the subframe bitmap represents a contiguous set of uplink subframes. For TDD, the subframe bitmap represents adjacent UL subframes according to the TDD configuration.

In addition, the subframe bitmap may have a different length depending on the FDD / TDD configuration. For FDD, the length of the subframe bitmap is 40. That is, the duration of one resource full bitmap is 40 ms. On the other hand, in the case of TDD, the length of the subframe bitmap may be set differently according to the TDD UL / DL configuration, and the number of uplink subframes may differ depending on the TDD UL / DL configuration It is because. Specifically, for example, the subframe bitmap length according to the TDD UL / DL configuration can be set as shown in Table 2 below.

TDD UL / DL configuration subframeBitmap length # of repetition to catch 200 valid D2D subframe (maximum of repetition #) Duration of 200 valid D2D subframe One 16 13 520ms 2 8 25 1s 3 12 17 680ms 4 8 25 1s 5 4 50 2s 0 42 5 350ms 6 30 7 420ms

Referring to Table 2, in the TDD UL / DL configuration 1, the length of the subframe bitmap is 16, in the TDD UL / DL configuration 2, the length of the subframe bitmap is 8, The length of the bitmap is 12, the length of the subframe bitmap in the TDD UL / DL configuration 4 is 8, and the length of the subframe bitmap in the TDD UL / DL configuration 5 is 4. For TDD UL / DL configurations 1 to 5, the duration of one resource full bitmap is 40 ms like FDD. In this case, FDD is 5, TDD UL / DL configuration 1 is 13, TDD UL / DL configuration 2 is 25, and TDD UL / DL configuration 3 is calculated by counting the maximum number of repetitions of resource full bitmap based on 200 valid D2D sub- 17, TDD UL / DL configuration 4 is 25, and TDD UL / DL configuration 5 is 50.

The length of the subframe bitmap in the TDD UL / DL configuration 0 is set to 42, and the length of the subframe bitmap in the TDD UL / DL configuration 6 is set to 30. For TDD UL / DL configuration 0, the duration of one resource full bitmap is 70 ms, and for TDD UL / DL configuration 6, the duration of one resource full bitmap is 60 ms. In this case, if the maximum number of repetitions of the resource full bitmap is calculated based on 200 effective D2D subframes, the TDD UL / DL configuration 0 is 5 and the TDD UL / DL configuration 6 is 7.

Meanwhile, a Resource Pattern for Transmission (RPT) may be used for D2D communication. In the time domain, RPT can be called T-RPT and can be defined in subframe units. The T-RPT can indicate through the T-RPT bitmap which resource (subframe) in the indicated resource pool to be actually transported by the indicated method of resource pool mentioned above. In this case, it is assumed that an MAC PDU carrying D2D data is repeatedly transmitted a specific number of times. Here, the specific number may be four. In this case, one transport block carrying D2D data is repeatedly transmitted on four subframes.

In a case where a normal HARQ operation for WAN communication using a physical channel such as PUSCH is set in the UE, the T-RPT for D2D data can be designed as follows.

The T-RPT index range may include up to 128 values (the T-RPT index may be set to 7 bits for SA, etc.). Each value of the T-RPT index is mapped to T-RPT. The T-RPT is derived from a length N bitmap.

Each bit of the T-RPT bitmap indicated by the T-RPT index indicates whether D2D transmission is performed in the associated sub-frame. When the bit value is 1, the D2D transmission is instructed, and when the bit value is 0, the D2D transmission is indicated.

The T-RPT can be divided based on the variables N and k, where N is the length of the T-RPT bitmap, k is the number of subframes in which the actual D2D data is transmitted (i.e., 1).

4 is a diagram for explaining a sub-frame indication according to a T-RPT bitmap. FIG. 4 shows an example of a case where N = 8 and k = 4 for a mode 2 data resource pool.

Referring to FIG. 4, each bit value 1 in the resource full bitmap indicates that the corresponding subframe is set as a resource pool. Since N = 8 for T-RPT in this embodiment, T-RPT indicates whether to transmit D2D for 8 subframes of the resource pool. Since k = 4, there is D2D transmission in four subframes out of the eight subframes (i.e., four bits out of the eight bits of the T-RPT bitmap are set to one). In this example, the T-RPT bitmap is set to 10101010 in this embodiment. In this case, the number 2, 5, subframe, and radio frame n + 1 of the radio frame n are 0, And subframes 1, 6, and 9 of radio frame n + 2 are indicated as subframes for D2D transmission. When combining the resource full bitmap and the T-RPT bitmap, it can indicate which D2D transmission is actually performed on which subframe. The T-RPT bitmap is repeatedly applied within the data resource pool.

N and k for T-RPT can be set according to the FDD / TDD configuration as follows.

First, in case of FDD, N = 8 for mode 1 and k can have a value of {1,2,4,8}. That is, k may have a value of 1, 2, 4, or 8. For FDD, N = 8 for mode 2 and k can have a value of {1,2,4}.

Also, for TDD UL / DL configuration 0, N = 7 for mode 1 and k can have a value of {1,2,4, N}. For TDD UL / DL configuration 0, for mode 2, N = 7 and k can have a value of {1,2,4}.

Also, for TDD UL / DL configurations 1, 2, 4, and 5, N = 8 for mode 1 and k can have a value of {1,2,4, N}. For TDD UL / DL configurations 1, 2, 4, and 5, for mode 2, N = 8 and k can have a value of {1,2,4}.

Also, for TDD UL / DL configurations 3 and 6, N = 6 for mode 1 and k can have a value of {1,2,4, N}. For TDD UL / DL configurations 3 and 6, for mode 2, N = 6 and k can have a value of {1,2,4}.

Of course, k may have additional values in addition to the listed values, and values other than the above-described values of k are not excluded.

A T-RPT bitmap of length N can be mapped to available D2D data subframes in the data scheduling interval.

The mapping using the T-PRT bitmap for mode 1 corresponds to adjacent consecutive UL subframes. As described above, since the Tx data resource pool is not set in the mode 1, the T-RPT bitmap of length N is applied to the continuous UL subframe in the data scheduling period.

For Mode 2, the mapping corresponds to UL subframes (data resource pools) indicated as 1 by the mode 2 data resource full bitmap. In Mode 2, unlike Mode 1, a subframe used for actual D2D transmission is indicated by utilizing a T-RPT bitmap on UL subframes indicated in the Tx resource full bitmap.

The above-mentioned T-RPT design is set considering the case where a normal HARQ operation is set for WAN communication in which the terminal is communicating with the base station. However, if a subframe bundling operation (TTI bundling) is set in the D2D terminal from a base station, a conflict between the WAN transmission and the D2D transmission when applying the T-RPT design designed in consideration of the normal HARQ operation So that the D2D transmission efficiency may be greatly reduced.

Here, the subframe bundling is used to increase reliable data transmission and UL coverage in a region where uplink transmission power of a UE is limited in a wireless communication system. For example, in a case where four consecutive UL subframes The same data having a HARQ process number can be transmitted on four consecutive UL subframes. The subframe bundling is applied when the "ttiBundling" parameter is set by upper layer (RRC) signaling, and may be called TTI (Transmit Time Interval) bundling. When using the sub-frame bundling, additional signaling overhead can be avoided when retransmission occurs, and the same transmission block (TB) can be divided into four consecutive sub-frames based on different RV (redundancy version) subframe or TTI), it is possible to improve transmission reliability and UL coverage. Subframe bundling is efficient in time sensitive traffic models such as VoIP.

5 is a diagram for explaining the concept of subframe bundling. 5 shows an example of a subframe bundling operation for FDD.

Referring to FIG. 5, one transport block is mapped on four subframes of the physical layer based on different RVs through cyclic redundancy check (CRC), coding, and RM (rate matching) . In this case, in applying the HARQ process, the same HARQ process number is applied to four subframes carrying the same transport block, and even when an HARQ ACK / NACK signal is fed back, Only one HARQ ACK / NACK signal is fed back based on the timing of the frame, and the retransmission is again performed on four subframes at the time of retransmission.

The HARQ processes for the case where the normal HARQ operation is set and the case where the subframe bundling operation is set are compared as follows. Hereinafter, the number of HARQ processes in the present invention may indicate the number of HARQ processes for WAN communication.

First, when the normal HARQ operation is set for the FDD, the maximum number of HARQ processes is 8. When the subframe bundling operation is set, the maximum HARQ process number is four as shown in FIG.

The maximum number of HARQ processes for TDD is shown in Table 3 below.

TDD UL / DL configuration Number of HARQ processes for normal HARQ operation Number of HARQ processes for subframe bundling operation 0 7 3 One 4 2 2 2 N / A 3 3 N / A 4 2 N / A 5 One N / A 6 6 3

Referring to Table 3, when the normal HARQ operation is set, the number of HARQ processes is 7, 4, 2, 3, and 2 for TDD UL / DL configurations 0, 1, 2, 3, 4, 5, , 1, and 6, respectively. When the subframe bundling operation is set, the number of HARQ processes is 3 for TDD UL / DL configuration 0, the number of HARQ processes is 2 for TDD UL / DL configuration 1, and the number of HARQ processes is 3 for TDD UL / . Subframe bundling may not be supported for the remaining TDD UL / DL configurations.

The length (N) of the T-RPT bitmap in the above-described T-RPT design is designed in consideration of the number of HARQ processes when a normal HARQ operation is set in the terminal. For example, with respect to FDD, the T-RPT bitmap length N for D2D data communication is set to 8, taking into account the number 8 of HARQ processes for normal HARQ operations. Through this, the base station can control WAN communication with the D2D terminal so that the number of HARQ processes affected by the D2D communication between the D2D terminals is minimized. In other words, the collision between WAN signal transmission and D2D signal transmission can be minimized. The minimization includes minimizing the influence of HARQ operations utilized in the WAN communication by minimizing the number of subframes of the corresponding HARQ process for WAN communication and subframes for D2D communication by the base station. And a T-RPT sub-frame (design).

FIG. 6 is a diagram for explaining a T-RPT design when an FDD and a normal HARQ operation are set in the UE. 6 is an example of a case of D2D data communication regarding mode 1 or mode 2 (with resource pool configuration).

Referring to FIG. 6, the number of HARQ processes (for WAN communication) is 8 when the normal HARQ operation is set, and the T-RPT bitmap length (for D2D communication) is 8. According to the T-RPT design described above, in the case of mode 1, k may have {1,2,4,8}, k = 4 in this embodiment, and the T-RPT bitmap indicates "11110000 ". In the case of mode 2, k may have {1,2,4}, k = 2 in this embodiment, and the T-RPT bitmap indicates "10010000 ". As described above, the T-RPT bitmap is repeatedly applied within the data resource pool period.

On the other hand, examples of the case where the TDD and the normal HARQ operation are set in the UE and the D2D data communication regarding Mode 1 or Mode 2 (with resource pool configuration) is as follows.

7 is a diagram for explaining a T-RPT design when a TDD UL / DL configuration 0 and a normal HARQ operation are set in the UE.

Referring to FIG. 7, when the normal HARQ operation is set, the number of HARQ processes is 7 and the T-RPT bitmap length is 7. According to the T-RPT design described above, in the case of the mode 1, k may have {1,2,4,7}, k = 4 in the present embodiment, and the T-RPT bitmap indicates "1111000 ". In mode 2, k may have {1,2,4}, k = 2 in this embodiment, and the T-RPT bitmap indicates "1001000 ".

8 is a view for explaining a T-RPT design when TDD UL / DL configuration 1 and normal HARQ operation are set in the UE.

Referring to FIG. 8, when the normal HARQ operation is set, the number of HARQ processes is 4 and the T-RPT bitmap length is 4. According to the T-RPT design described above, in the case of mode 1, k may have {1,2,4,8}, k = 4 in this embodiment, and the T-RPT bitmap indicates "11110000 ". In the case of mode 2, k may have {1,2,4}, k = 2 in this embodiment, and the T-RPT bitmap indicates "10010000 ".

FIG. 9 is a diagram for explaining a T-RPT design when the TDD UL / DL configuration 6 and the normal HARQ operation are set in the UE.

Referring to FIG. 9, when the normal HARQ operation is set, the number of HARQ processes is 6 and the T-RPT bitmap length is 6. According to the T-RPT design described above, in the case of mode 1, k may have {1,2,4,6}, k = 4 in this embodiment, and the T-RPT bitmap indicates "111100 ". In the case of mode 2, k may have {1,2,4}, k = 2 in this embodiment, and the T-RPT bitmap indicates "100100 ".

In the above examples, since the number of HARQ processes for the normal HARQ operation and the T-RPT bitmap length N are equal to or multiples of each other, the influence of the collision between the HARQ process and the D2D transmission is minimized .

Meanwhile, when subframe bundling is set up in the UE, as shown in Table 3, the number of HARQ processes is different from that in the case where the normal HARQ operation is set. Therefore, when the T-RPT design is applied as it is, And it is necessary to change the T-RPT design for the case where sub-frame bundling is set up in the D2D terminal in order to provide more efficient resource setting and coexistence with WAN communication to the D2D terminal.

The modified T-RPT design for the case where the sub-frame bundling according to the present invention is set in the terminal may have the following features.

The T-RPT index indicating the T-RPT for when the sub-frame bundling is set can be set to L bits. For example, L may be 4 or less. T-RPT is derived from a bit value of length L (derived from). That is, T-RPT is indicated according to the value of the T-RPT index of the bit length L. [

The T-RPT can be divided based on the variables L, N and k, where N is the length of the T-RPT (the number of D2D subframes represented by T-RPT), k is the number of subframes (I.e., the number of subframes whose value is 1 in the T-RPT).

L, N and k for T-RPT can be set as follows according to the FDD / TDD configuration.

First, in case of FDD, L = 4, N = 16, and k can have a value of {4,8,12,16}. That is, k may have a value of 4, 8, 12, or 16.

Further, in the case of TDD UL / DL configuration 0, L = 3, N = 12 and k can have a value of {4,8,12}.

Further, in the case of TDD UL / DL configuration 1, L = 3, N = 8 and k can have a value of {4, 8}.

Also, in the TDD UL / DL configuration 6, L = 3, N = 12 and k can have a value of {4,8,12}.

Of course, k may have additional values in addition to the listed values, and values other than the above-described values of k are not excluded.

The value of the T-RPT index of length L represents the T-RPT in the D2D data subframes available in the data scheduling interval. For example, the specific correspondence can be expressed as shown in Tables 4 to 7 below.

T-RPT index
(L = 4) N k T-RPT for subframe bundling and FDD One 16 4 1111000000000000 2 0000111100000000 3 0000000011110000 4 0000000000001111 5 8 1111111100000000 6 0000111111110000 7 0000000011111111 8 1111000000001111 9 1111000011110000 10 0000111100001111 11 12 1111111111110000 12 0000111111111111 13 1111000011111111 14 1111111100001111 15 16 1111111111111111

T-RPT index
(L = 3) N k T-PRT for subframe bundling and TDD UL / DL configuration # 0 One 12 4

111100000000 2 000011110000 3 000000001111 4 8

111111110000 5 000011111111 6 111100001111 7 12 111111111111

T-RPT index
(L = 2) N k T-PRT for subframe bundling and TDD UL / DL configuration # 1 One 8 4 11110000 2 00001111 3 8 11111111

T-RPT index
(L = 3) N k T-PRT for subframe bundling and TDD UL / DL configuration # 6 One 12 4

111100000000 2 000011110000 3 000000001111 4 8

111111110000 5 000011111111 6 111100001111 7 12 111111111111

However, it is needless to say that the corresponding relationship of the T-RPT according to the T-RPT index value may be applied to other correspondence relationships according to the intra-network appointment as an example. For example, in Table 4, when the T-RPT index value is 1, T-RPT " 1111000000000000 "is indicated. However, the T-RPT index value may indicate T-RPT" 1111000000000000 " Or may indicate T-RPT "0000000000001111" when the T-RPT index value is 1, and so on.

FIGS. 10-13 illustrate examples of T-RPT designs for terminals with server frame bundling established. The T-RPT design according to Figs. 10-13 can be applied in the case of a D2D data communication with mode 1 or mode 2 (with resource pool configuration).

Figure 10 is an example of a T-RPT design for a terminal with FDD and sub-frame bundling enabled.

Referring to FIG. 10, four HARQ processes are utilized in the FDD, and four consecutive UL subframes are used per HARQ process. FIG. 10A shows an example of a case where the T-RPT design for the case where the normal HARQ operation is set in the UE is applied as it is, specifically, T-RPT for N = 8 and k = 4. On the other hand, FIG. 10B shows a case in which a modified T-RPT design is applied for a case where sub-frame bundling is set in the terminal.

11 is an example of a T-RPT design for a UE with TDD UL / DL configuration 0 and subframe bundling.

Referring to FIG. 11, three HARQ processes are utilized in a TDD UL / DL configuration, and adjacent four UL subframes are used per HARQ process. 11A shows an example of a case where the T-RPT design for the case where the normal HARQ operation is set in the UE is applied as it is. Specifically, T-RPT for N = 7 and k = 4 is shown. On the other hand, FIG. 11 (b) shows a case where a modified T-RPT design is applied for the case where sub-frame bundling is set in the terminal.

Figure 12 is an example of a T-RPT design for a UE with TDD UL / DL configuration 1 and sub-frame bundling established.

Referring to FIG. 12, two HARQ processes are utilized in a TDD UL / DL configuration, and adjacent four UL subframes are used per HARQ process. 12A is an example of a case where the T-RPT design for the case where the normal HARQ operation is set in the UE is applied as it is, specifically, T-RPT for N = 8 and k = 4. On the other hand, FIG. 12 (b) shows a case where a modified T-RPT design is applied for the case where sub-frame bundling is set in the terminal.

13 is an example of a T-RPT design for a UE with TDD UL / DL configuration 6 and sub-frame bundling.

Referring to FIG. 13, three HARQ processes are utilized in a TDD UL / DL configuration, and adjacent four UL subframes are used per HARQ process. FIG. 13A shows an example of a case where the T-RPT design for the case where the normal HARQ operation is set in the UE is applied as it is, specifically, T-RPT for N = 6 and k = 4. On the other hand, FIG. 13 (b) shows a case where a modified T-RPT design is applied for the case where sub-frame bundling is set in the terminal.

As shown in FIGS. 10 (a) to 13 (a), when the T-RPT design for the case where the normal HARQ operation is set in the UE for the UE having the sub-frame bundling is applied as it is, And the T-RPT bitmap length do not match each other, and in some cases, one HARQ process may exist over two T-RPTs. In this case, there are frequent collisions between resources for WAN communication and resources for D2D communication, and considering the priority of WAN communication, the transmission efficiency / performance due to drop or abandonment of D2D transmission / Can be lowered.

On the other hand, as shown in FIGS. 10 (b) to 13 (b), when applying the modified T-RPT design for the case where the sub-frame bundling is set in the terminal, (Length of D2D subframes indicated by T-RPT) considered to be used for D2D communication (uplink subframe) or by designing in the form of a multiple, a resource for WAN communication and a resource for D2D communication RPT can be minimized and the T-RPT can be represented based on lesser T-RPT index bits.

On the other hand, a sub-frame bundling indicator may be included in the SA information transmitted from the Tx terminal to the Rx terminal to notify the D2D Rx terminal that a modified T-RPT design for the D2D Tx terminal is applied for WAN communication. The subframe bundling indicator may indicate whether or not a subframe bundling operation is set in the Tx terminal. For example, the subframe bundling indicator may have a length of one bit. The Rx UE can know information on the T-RPT used for D2D data reception through the sub-frame bundling indicator in the SA, and can perform decoding of the D2D data packet based on the information.

FIG. 14 exemplarily shows a flowchart of a base station (mode 1) or a D2D Tx terminal (mode 2) performing resource control for D2D communication.

Referring to FIG. 14, in step S1400, the BS determines whether the D2D Tx terminal has a T-RPT type based on whether sub-frame bundling is established or not. Here, the T-RPT type may include a type according to the normal T-RPT design for the terminal in which the normal HARQ operation is set up and a type according to the modified T-RPT design for the terminal in which the sub-frame bundling operation is set. If the sub-frame bundling is not set in the D2D Tx terminal, the base station can apply the type according to the normal T-RPT design. If the D2D Tx terminal has sub-frame bundling, the base station applies the changed T- can do. The base station may configure sub-frame bundling on the D2D Tx terminal based on RRC signaling. For example, the base station may include a MAC-MainConfig IE (Information Element) in an RRC connection reconfiguration message, and the MAC-MainConfig IE may include a "ttiBundling" parameter. It may indicate whether sub-frame bundling is set in the D2D Tx terminal based on the "ttiBundling" parameter.

The base station determines a T-RPT index for the D2D Tx terminal based on the determined T-RPT type (S1410). For example, in the case of the type according to the normal T-RPT design, the T-RPT index can be represented by a bitmap of length N. [ When the mode 1 is set in the D2D Tx terminal, since the Tx data resource pool is not set, the T-RPT bitmap of length N can be applied on the continuous UL subframe in the data scheduling period. When the mode 2 is set in the D2D Tx terminal, the T-RPT bitmap of length N corresponds to the UL subframes (which is the data resource pool) indicated by 1 by the mode 2 data resource full bitmap. In Mode 2, unlike Mode 1, a subframe used for actual D2D transmission is indicated by utilizing a T-RPT bitmap on UL subframes indicated in the Tx resource full bitmap.

As another example, in the case of the type according to the modified T-RPT design, the T-RPT index can be represented by a bit value of the bit length L. [ The value of the T-RPT index may indicate T-RPT for N sub-frames. In other words, the value of the T-RPT index of length L may represent the T-RPT in the D2D data subframes available in the data scheduling interval, for example, the specific correspondence may be expressed as in Tables 4-7 have.

The base station generates a D2D grant including the determined T-RPT index, and transmits the generated D2D grant to the D2D Tx terminal (S1420). The D2D grant may be transmitted in the Downlink Control Information (DCI) of the PDCCH / EPDCCH.

15 illustrates an exemplary D2D Tx terminal flow diagram for performing D2D communication.

Referring to FIG. 15, the D2D Tx terminal determines a T-RPT index for D2D communication (S1500). In one example, the D2D Tx terminal may receive a D2D grant from the base station that includes a T-RPT index. As another example, the D2D Tx terminal may select the T-RPT index directly according to a predetermined algorithm.

The D2D Tx terminal determines whether the T-RPT indicates a T-RPT based on whether or not sub-frame bundling is set (S1510). If the sub-frame bundling is not set, the D2D Tx terminal can apply the type according to the normal T-RPT design. If the sub-frame bundling is set, the D2D Tx terminal can apply the changed T-RPT design type. The D2D Tx UE can determine whether sub-frame bundling is set based on the RRC signaling. The D2D Tx terminal can detect the T-RPT for D2D data transmission based on the T-RPT design type and the T-RPT index. The T-RPT indicates subframes for D2D data transmission. For example, in the case of the type according to the normal T-RPT design, the T-RPT index is represented by a bitmap of length N, and the bitmap is indicated on the contiguous UL subframe in the scheduling interval or in the Tx resource full bitmap Lt; RTI ID = 0.0 > UL < / RTI > In another example, for a type according to the modified T-RPT design, the value of the T-RPT index of length L may indicate T-RPT in the D2D data subframes available in the data scheduling interval, The specific correspondence can be represented as Tables 4 to 7.

The D2D Tx terminal generates a D2D SA and transmits it to the D2D Rx terminal (S1520). The D2D SA may include a T-RPT index and a sub-frame bundling indicator. The sub-frame bundling indicator may indicate whether or not a sub-frame bundling operation is set in the D2D Tx terminal. For example, the sub-frame bundling indicator may have a length of one bit. In order to facilitate detection of the SA channel of the D2D Rx UE, the SA size (format) provided by the UE with the subframe bundling established and the SA size provided by the Tx UE performing the normal HARQ operation can be kept the same, The fields may have fixed positions and bit values. This is to avoid unnecessary blind decoding at the Rx terminal.

The D2D Tx terminal maps the D2D data on the subframes indicated by the T-RPT and transmits the D2D data to the Rx terminal (S1530). One D2D data MAC PDU may be repeatedly transmitted four times on the subframes indicated by the T-RPT.

FIG. 16 exemplarily shows a flowchart of a D2D Rx terminal performing D2D communication.

Referring to FIG. 16, the D2D Rx terminal receives the D2D SA from the D2D Tx terminal (S1600). The D2D SA may include a T-RPT index and a sub-frame bundling indicator.

The D2D Rx terminal determines whether sub-frame bundling is set in the D2D Tx terminal based on the sub-frame bundling indicator (S1610). For example, the subframe bundling indicator may have a length of one bit. The sub-frame bundling indicator may be set through an RRC connection reconfiguration message. The sub-frame bundling indicator may be set to a UE-specific value. It can be determined that sub-frame bundling is set in the D2D Tx UE when the sub-frame bundling indicator bit value is 1, and it can be determined that the normal HARQ operation is set in the D2D Tx UE when the bit value is 0. [

The D2D Rx terminal determines whether the T-RPT index indicated by the T-RPT index is determined based on whether or not sub-frame bundling is set (S1620). The D2D Rx terminal can determine the T-RPT based on the type according to the normal T-RPT design if no subframe bundling is set in the Tx terminal, and when the subframe bundling is set in the Tx terminal, the changed T- The T-RPT can be determined based on the design type. The D2D Rx terminal can detect the T-RPT for D2D data transmission based on the T-RPT design type and the T-RPT index. The T-RPT indicates subframes for D2D data reception.

The D2D Rx terminal receives the D2D data on the subframes indicated by the T-RPT (S1630).

For example, referring to FIGS. 11 and 5, when a sub-frame bundling and a TDD UL / DL configuration 0 for WAN communication are set in the D2D Tx terminal, the T-RPT index has a 3-bit size (L = 3) And the T-RPT length (the length of the D2D subframes represented by T-PRT) N = 12. If the D2D Tx terminal uses the T-RPT indicated by the T-RPT index 1 determined by the base station's control or self selection for D2D data transmission, the D2D Tx terminal uses the T-RPT index value 1 (and sub- The indicator bit value 1) is included in the SA and is transmitted to the D2D Rx terminal. Through this, the D2D Rx UE can know which subframe among the available D2D subframes within a predetermined D2D data interval will receive the D2D data. Since the T-RPT index value is 1, the D2D Tx UE can transmit D2D data on subframes 2, 3, 4, and 7, and the D2D Rx UE can receive D2D data on the corresponding subframes. In this case, one D2D MAC PDU (one D2D TB) can be transmitted four times repeatedly. In this case, there is an advantage that the T-RPT index having a smaller size than the case where the normal HARQ operation is set can be instructed while minimizing the collision with the WAN communication.

As described with reference to FIG. 14 to FIG. 16, the T-RPT index indicates a T-RPT having a different length (L = 4 in case of FDD) depending on whether the current serving cell accessed by the UE is FDD or TDD. You can have an index. Also, when the serving cell is TDD, the T-RPT index may have a different length (L = 2, 3) according to the TDD UL / DL configuration of the serving cell. Here, the TDD UL / DL configuration may be transmitted to the UEs through the SIB1 (System Information Block 1).

In addition, the subframe bundling indicator may be set through an RRC connection reconfiguration message. The sub-frame bundling indicator may be set to a UE-specific value.

17 is a block diagram illustrating a base station, a D2D Tx terminal, and a D2D Rx terminal according to an embodiment of the present invention.

17, the base station 1700 includes a memory 1705, a processor 1710, and a RF unit (RF) unit 720. [ Memory 1705 is coupled to processor 1710 to store various information for driving processor 1710. RF section 1720 is coupled to processor 1710 to transmit and / or receive wireless signals. Processor 1710 implements the proposed functions, procedures, and / or methods for performing operations in accordance with the present invention. In the embodiments described above, the operation of the base station may be implemented by control of processor 1710. [

The processor 1710 includes a bundling determination unit 1711, a T-RPT index determination unit 1712, and a D2D communication control unit 1713.

The bundling determination unit 1711 determines whether or not sub-frame bundling is set in the D2D Tx terminal 1730. The bundling determination unit 1711 can determine whether to set the subframe bundling based on the "ttiBundling" parameter, which is the RRC parameter set in the D2D Tx terminal 1730. [

The T-RPT index determiner 1712 determines or determines the T-RPT type for the D2D Tx terminal based on whether the sub-frame bundling is set or not. For example, the T-RPT index determination unit 1712 can determine the normal T-RPT design type when the sub-frame bundling is not set. As another example, the T-RPT index determiner 1712 may determine the modified T-RPT design type described above when sub-frame bundling is set.

Also, the T-RPT index determiner 1712 determines or determines a T-RPT index for the D2D Tx terminal based on the determined T-RPT type. For example, in the case of the type according to the normal T-RPT design, the T-RPT index may be represented by a bitmap of length N. [ As another example, in the case of the type according to the modified T-RPT design, the T-RPT index can be represented by a bit value of the bit length L. [ The value of the T-RPT index may indicate T-RPT for N sub-frames. In other words, the value of the T-RPT index of length L may represent the T-RPT in the D2D data subframes available in the data scheduling interval, for example, the specific correspondence may be expressed as in Tables 4-7 have.

The D2D communication control unit 1713 generates a D2D grant including the determined T-RPT index and transmits the generated D2D grant to the D2D Tx terminal 1730 through the RF unit 1720. [ RF section 1720 may also send an RRC message including the "ttiBundling" parameter to D2D Tx terminal 1730. [

The D2D Tx terminal 1730 includes a memory 1735, a processor 1740, and an RF section 1750. The memory 1735 is coupled to the processor 1740 to store various information for driving the processor 1740. RF section 1750 is coupled to processor 1740 to transmit and / or receive wireless signals. Processor 1740 implements the proposed functions, procedures and / or methods for performing the operations according to the present invention. The operation of the D2D Tx terminal in the above-described embodiments may be implemented by control of the processor 1740. [

RF section 1750 can receive the "ttiBundling" parameter via RRC signaling and receive the D2D grant including the T-RPT index.

The processor 1740 includes a bundling determination unit 1741, a T-RPT determination unit 1742, and a D2D communication control unit 1743.

The bundling determination unit 1741 determines whether or not sub-frame bundling is set in the D2D Tx terminal 1730. The bundling determination unit 1741 can determine whether to set the sub-frame bundling based on the "ttiBundling" parameter.

The T-RPT determination unit 1742 determines a T-RPT index for D2D communication. For example, the T-RPT determination unit 1742 may receive a D2D grant including a T-RPT index from the base station 1700 and determine a T-RPT index for D2D communication via the received T-RPT have. As another example, the T-RPT determination unit 1742 may directly select the T-RPT index according to a predetermined algorithm.

The T-RPT determination unit 1742 determines the T-RPT indicated by the T-RPT index based on whether the sub-frame bundling is set or not. The T-RPT index indicated by the T-RPT index may vary depending on whether the sub-frame bundling is set or not, and the T-RPT determination unit may determine or detect the T-RPT based on the sub-frame establishment and the T-RPT index . For example, the T-RPT determination unit 1742 applies the normal T-RPT design type when the sub-frame bundling is not set, determines that the T-RPT index is a bitmap of length N, Lt; RTI ID = 0.0 > UL < / RTI > subframes indicated on the contiguous UL subframe or the Tx resource full bitmap. In another example, the T-RPT determination unit 1742 applies the changed T-RPT design type when sub-frame bundling is set, and generates a D2D data sub-frame based on the value of the T- RPTs in frames, where the correspondence between the T-RPT index and the T-RPT can be represented, for example, as in Tables 4-7.

The D2D communication control section 1743 generates the D2D SA. The D2D SA may include a T-RPT index and a sub-frame bundling indicator. The sub-frame bundling indicator may indicate whether or not a sub-frame bundling operation is set in the D2D Tx terminal. For example, the sub-frame bundling indicator may have a length of one bit. The RF unit 1750 transmits the D2D SA to the D2D Rx terminal 1760.

The D2D communication control unit 1743 maps the D2D data on the subframes indicated by the T-RPT and transmits the D2D data to the D2D Rx terminal 1760 through the RF unit 1750. The D2D communication control unit 1743 may transmit one D2D data MAC PDU to the D2D Rx terminal 1760 through the RF unit 1750 four times on the subframes indicated by the T-RPT.

The Rx terminal 1760 includes a memory 1765, a processor 1770, and an RF section 1780. The memory 1765 is coupled to the processor 1770 and stores various information for driving the processor 1770. RF section 1780 is coupled to processor 1770 to transmit and / or receive wireless signals. Processor 1770 implements the proposed functions, procedures and / or methods for performing the operations according to the present invention. The operation of the D2D Rx terminal in the above-described embodiment may be implemented by control of the processor 1770. [

The RF unit 1780 receives the D2D SA from the D2D Tx terminal 1760. Where the D2D SA may include a T-RPT index and a sub-frame bundling indicator. In this case, the RF unit 1780 can receive the D2D SA on the D2D SA receiving resource pool.

The processor 1770 includes a bundling determination unit 1771, a T-RPT determination unit 1772, and a D2D communication control unit 1773.

The bundling determination unit 1771 determines whether sub-frame bundling is set in the D2D Tx terminal 1730 based on the sub-frame bundling indicator. For example, when the bit value of the subframe bundling indicator is 1, the bundling determination unit 1771 determines that the subframe bundling is set in the D2D Tx terminal 1730. If the bit value is 0, the D2D Tx terminal 1730 It can be determined that the normal HARQ operation is set.

The T-RPT determination unit 1772 determines the T-RPT indicated by the received T-RPT index based on whether the sub-frame bundling is set or not. The T-RPT index indicated by the T-RPT index may vary depending on whether the sub-frame bundling is set or not, and the T-RPT determination unit may determine or detect the T-RPT based on the sub-frame establishment and the T-RPT index . The T-RPT index indicated by the T-RPT index may vary depending on whether the sub-frame bundling is set or not, and the T-RPT determination unit may determine or detect the T-RPT based on the sub-frame establishment and the T-RPT index . For example, the T-RPT determination unit 1772 applies the normal T-RPT design type when sub-frame bundling is not set, determines the T-RPT index as a bit map of length N, Lt; RTI ID = 0.0 > UL < / RTI > subframes indicated on the contiguous UL subframe or the Tx resource full bitmap. In another example, the T-RPT determination unit 1772 applies the changed T-RPT design type when sub-frame bundling is set, and generates a D2D data sub-frame based on the value of the T- RPTs in frames, where the correspondence between the T-RPT index and the T-RPT can be represented, for example, as in Tables 4-7.

The D2D communication control unit 1773 detects sub-frames for receiving D2D data indicated by the T-RPT, and receives D2D data on the sub-frames via the RF unit 1780. [

A processor in the present invention may include an application-specific integrated circuit (ASIC), another chipset, a logic circuit, and / or a data processing device. The memory may include read-only memory (ROM), random access memory (RAM), flash memory, memory cards, storage media, and / or other storage devices. The RF unit may include a baseband circuit for processing the radio signal. When the embodiment is implemented in software, the above-described techniques may be implemented with modules (processes, functions, and so on) that perform the functions described above. The module is stored in memory and can be executed by the processor. The memory may be internal or external to the processor and may be coupled to the processor by any of a variety of well known means.

In the above-described exemplary system, the methods are described on the basis of a flowchart as a series of steps or blocks, but the present invention is not limited to the order of the steps, and some steps may occur in different orders . It will also be understood by those skilled in the art that the steps shown in the flowchart are not exclusive and that other steps may be included or that one or more steps in the flowchart may be deleted without affecting the scope of the invention.

The above-described embodiments include examples of various aspects. While it is not possible to describe every possible combination for expressing various aspects, one of ordinary skill in the art will recognize that other combinations are possible. Accordingly, it is intended that the invention include all alternatives, modifications and variations that fall within the scope of the following claims.

Claims (13)

A method for controlling D2D resource setting by a base station in a wireless communication system supporting device-to-device communication (D2D)
Determining a T-RPT (Time Domain-Resource Pattern for Transmission) type for the D2D Tx terminal based on whether sub-frame bundling is set in the D2D Tx terminal;
Determining a T-PRT index for the D2D Tx terminal based on the determined T-RPT type;
Generating a D2D grant comprising the T-RPT index; And
And transmitting the generated D2D grant to the D2D Tx terminal. The method according to claim 1,
Wherein the T-PRT type is divided into a normal T-PRT type for a UE for which a normal HARQ operation is established and a changed T-RPT type for a UE to which a sub-frame bundling is established. 3. The method of claim 2,
The T-RPT index indicates sub-frames for D2D data transmission through a bitmap indicating a corresponding index, and when the T-RPT index is based on the changed T-RPT type, ≪ / RTI > wherein the index value indicates a set of subframes corresponding to an index value. 3. The method of claim 2,
The T-RPT index based on the normal T-RPT type indicates whether or not to use N subframes for D2D data transmission as a bitmap of length N, and when the T-RPT index is based on the changed T-RPT type, Wherein the index indicates whether or not to use for the D2D data transmission of N subframes with a bit value of length L, where L is less than N. < RTI ID = 0.0 > The method according to claim 1,
Further comprising transmitting to the D2D Tx terminal a "ttiBundling" parameter indicating whether to set up sub-frame bundling. In a D2D communication method performed by a D2D Tx terminal in a wireless communication system supporting a device to device (D2D) communication,
Determining a T-PRT (Time Domain-Resource Pattern for Transmission) index for D2D communication;
Determining a T-PRT indicated by a T-PRT index based on whether or not subframe bundling is set;
Generating a sub-frame bundling indicator indicating whether to set up the sub-frame bundling and a D2D SA (Scheduling Assingment) including the T-RPT index;
Transmitting the generated D2D SA to a D2D Rx terminal; And
Mapping the D2D data onto the sub-frames indicated by the T-RPT and transmitting the D2D data to the D2D Rx terminal. The method according to claim 6,
Further comprising receiving from the base station a D2D grant comprising the T-RPT index. The method according to claim 6,
Characterized in that the T-RPT is determined by the D2D Tx terminal according to a predetermined algorithm. The method according to claim 6,
Determining a T-PRT indicated by a T-PRT index based on whether the sub-frame bundling is set up,
Determining a T-RPT type for the D2D Tx terminal based on whether the sub-frame bundling is set in the D2D Tx terminal; And
And determining the T-RPT indicated by the T-RPT index based on the T-RPT type. The method according to claim 6,
The T-RPT type is classified into a normal T-PRT type for a UE for which a normal HARQ operation is established and a changed T-RPT type for a UE to which a sub-frame bundling is established,
The T-RPT index based on the normal T-RPT type indicates whether or not to use N subframes for D2D data transmission as a bitmap of length N, and when the T-RPT index is based on the changed T-RPT type, Wherein the index indicates whether or not to use for the D2D data transmission of N subframes with a bit value of length L, wherein L is less than N. A D2D communication method performed by a D2D Rx terminal in a wireless communication system supporting inter-device communication (Device to Device, D2D)
Receiving a D2D SA (Scheduling Assignment) including a sub-frame bundling indicator and a time domain-resource pattern for transmission (T-RPT) index from a D2D Tx terminal on a D2D SA receiving resource pool;
Determining whether sub-frame bundling is set in the D2D Tx terminal based on the sub-frame bundling indicator;
Determining a T-RPT indicated by the T-RPT index based on whether the sub-frame bundling is set or not; And
And receiving D2D data from the D2D Tx terminal on subframes indicated by the T-RPT. 12. The method of claim 11,
Determining a T-PRT indicated by a T-PRT index based on whether the sub-frame bundling is set up,
Determining a T-RPT type for the D2D Tx terminal based on whether the sub-frame bundling is set in the D2D Tx terminal; And
And determining the T-RPT indicated by the T-RPT index based on the T-RPT type. 12. The method of claim 11,
The T-RPT type is classified into a normal T-PRT type for a UE for which a normal HARQ operation is established and a changed T-RPT type for a UE to which a sub-frame bundling is established,
The T-RPT index based on the normal T-RPT type indicates whether or not to use N subframes for D2D data transmission as a bitmap of length N, and when the T-RPT index is based on the changed T-RPT type, Wherein the index indicates whether or not to use for the D2D data transmission of N subframes with a bit value of length L, wherein L is less than N.

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