KR20140080389A

KR20140080389A - Method and apparatus for transmitting/receiving ack/nack in d2d communication

Info

Publication number: KR20140080389A
Application number: KR1020120150112A
Authority: KR
Inventors: 김종남; 박경민
Original assignee: 주식회사 팬택
Priority date: 2012-12-20
Filing date: 2012-12-20
Publication date: 2014-06-30

Abstract

The present invention relates to a technique for transmitting / receiving ACK / NACK in D2D communication, and provides a method for a terminal to transmit / receive an ACK / NACK for data reception via PHICH or PUCCH.

Description

TECHNICAL FIELD [0001] The present invention relates to a method and apparatus for ACK / NACK transmission and reception in D2D communication,

The present invention relates to a technology for transmitting and receiving ACK / NACK in D2D (Device to Device) communication.

As the spread of mobile terminals such as smart phones and the demand for various services using such mobile terminals have been developed, inter-terminal communication capable of directly transmitting data between terminals without passing through network infrastructures such as base stations and access points has been highlighted.

For example, LTE (Long Term Evolution) or LTE-Advanced network, in order to provide more diversified services to users, to guarantee the reliability of communication between terminals, or to increase communication capacity through more efficient use of bandwidth. There is a demand for a technology for supporting communication between terminals by using radio resources of various mobile communication networks.

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

It is necessary to define a method of transmitting and receiving ACK / NACK for feedback of data reception in D2D (Device to Device) communication.

According to an aspect of the present invention, there is provided a method of transmitting ACK / NACK for data reception by a terminal receiving data from another terminal, the method comprising: receiving uplink or downlink scheduling information for transmission / And an ACK / NACK for the data reception through a Physical Uplink Indicator Channel (PHICH) or a Physical Uplink Control Channel (PUCCH). And transmitting the ACK / NACK message.

According to another aspect of the present invention, there is provided a method for receiving an ACK / NACK for data reception from a terminal, the base station receiving data from another terminal, the method comprising the steps of: performing uplink or downlink scheduling And a Physical Uplink Control Channel (PUCCH) for receiving ACK / NACK for data reception after the UE receives the data through the allocated data channel according to the uplink or downlink scheduling information, And receiving the ACK / NACK from the UE.

According to another aspect of the present invention, there is provided a terminal for receiving data from another terminal and transmitting an ACK / NACK for the data reception, the terminal comprising: an uplink or downlink scheduling information receiving / An ACK / NACK for the data reception is transmitted through a receiver for receiving the data through an allocated data channel according to uplink or downlink scheduling information and a Physical Uplink Indicator Channel (PHICH) or a Physical Uplink Control Channel (PUCCH) And a terminal including a transmitting unit.

According to another aspect of the present invention, there is provided a base station for receiving an ACK / NACK for data reception from a terminal for receiving data from another terminal, the base station comprising: an uplink or downlink scheduling information transmission / A Physical Uplink Control Channel (PUCCH) for transmitting ACK / NACK for data reception after receiving the data through a data channel allocated according to the uplink or downlink scheduling information, And a receiving unit for receiving the signal from the base station.

A method of transmitting / receiving ACK / NACK for feedback of data reception in D2D communication is provided.

FIG. 1 is a schematic view of a wireless communication system to which embodiments are applied.
FIG. 2 is an exemplary flow diagram of resource allocation and data transmission for D2D terminals.
3 is an exemplary diagram of a PHICH group index and a sequence index.
FIG. 4 shows that control channels and data channels are transmitted in D2D communication.
5 is a flowchart of downlink transmission and uplink transmission in the wireless communication system of FIG.
FIG. 6 illustrates a scheme in which control information according to each PUCCH format is mapped to a resource block (RB).
FIG. 7 shows that uplink scheduling information and downlink scheduling information are independently transmitted in D2D communication.
FIG. 8 shows an example in which collision of PUCCH resources occurs.
9 is a flowchart illustrating an ACK / NACK transmission method of a UE according to an embodiment of the present invention.
10 is a flowchart illustrating a method of receiving an ACK / NACK of a base station according to another embodiment of the present invention.
11 is a block diagram of a UE according to another embodiment of the present invention.
12 is a block diagram 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 symbols as possible even if 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.

In describing the components of the present invention, terms such as first, second, A, B, (a), and (b) may be used. These terms are intended to distinguish the constituent elements from other constituent elements, and the terms do not limit the nature, order or order of the constituent elements. When a component is described as being "connected", "coupled", or "connected" to another component, the component may be directly connected to or connected to the other component, It should be understood that an element may be "connected,""coupled," or "connected."

FIG. 1 is a schematic view of a wireless communication system to which embodiments are applied.

The wireless communication system 100 is widely deployed to provide various communication services such as voice, packet data, and so on.

1, a wireless communication system 100 includes a first user equipment (UE) 120, a second user equipment (UE) 120, and a base station 110 (BS).

The term " UE " in this specification refers to a user terminal in a wireless communication, and UE (User Equipment) in WCDMA (Wideband Code Division Multiple Access), LTE (Long Term Evolution) and HSPA Of course, it should be interpreted as a concept including all of MS (Mobile Station), UT (User Terminal), SS (Subscriber Station), and wireless device in Global System for Mobile communications (GSM).

Each of the terminals can perform feedback of channel information described below and provides the apparatus.

A base station 110 or a cell is generally a station that communicates with a terminal and includes a Node-B, an evolved Node-B (eNB), a Base Transceiver System (BTS), an access point Access Point, Relay Node, and the like.

The base station 110 transmits a reference signal to the terminals 120 and 122, receives channel information from the terminals 120 and 122, and can transmit data or signals using the channel information.

That is, the base station 110 or the cell in the present specification should be construed as a comprehensive meaning indicating a partial area covered by a BSC (Base Station Controller) in CDMA (Code Division Multiple Access), a Node-B in WCDMA And covers various coverage areas such as megacell, macrocell, microcell, picocell, femtocell, and relay node communication range.

The term " terminal " and " base station 110 " are used herein in their broadest 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 any specific term or word.

There is no limit to the multiple access scheme that is applied to the wireless communication system 100. 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.

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.

One embodiment is applied to asynchronous wireless communication that evolves into LTE (Long Term Evolution) and LTE-advanced via GSM, WCDMA, and HSPA, and synchronous wireless communication that evolves into CDMA, CDMA-2000, and UMB (Ultra Mobile Broadband) . The present invention should not be construed to be limited 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.

The wireless communication system 100 to which embodiments are applied may support uplink and / or downlink HARQ (Hybrid ARQ) and may use a channel quality indicator (CQI) for link adaptation. For example, the downlink may be OFDMA (Orthogonal Frequency Division Multiple Access), the uplink may be a Single Carrier-Frequency Division Multiple Access (SC-FDMA) ) Can be used.

D2D (Device to Device) communication is a communication in which terminals 120 and 122 in the same cell or cells adjacent to each other establish a D2D link (connection) with each other, and then directly transmit and receive data via a D2D link . Hereinafter, a wireless communication system will be described as an example of an LTE communication system, but the present invention is not limited thereto and applicable to any wireless communication system.

FIG. 2 is an exemplary flow diagram of resource allocation and data transmission for D2D terminals.

2, if there is data to be transmitted from the UE1 120 to the UE2 122 in a situation where connection between UEs performing D2D communication is established, the UE1 120 transmits a Scheduling Request , SR) through a Physical Uplink Control Channel (PUCCH) (S202). The BS 110 transmits uplink scheduling information (UL grant) for a buffer status report (BSR) to a Physical Downlink Control Channel (PDCCH) in order to determine the amount of data to be transmitted from the UE1 120 to the UE2 122, To the UE1 120 (S204). Then, the UE1 120 transmits the BSR to the BS 110 via a Physical Uplink Control Channel (PUSCH) (S206).

The base station transmits uplink scheduling information on data to be transmitted to the UE2 122 according to the BSR of the UE1 120 to the UE1 120 through the PDCCH (S208). At this time, uplink scheduling information or downlink scheduling information for receiving data transmitted by the UE1 120 may be transmitted from the base station to the UE2 122 through the PDCCH (S210).

The UE1 120 and the UE2 122 can receive radio resources for data transmission and reception through the radio resources PUSCH through the steps S208 and S210 and the UE1 120 and the UE2 122 transmit data (S212). The UE 2 120 transmits data through the uplink band in step S212 so that the data transmission procedure of the UE1 120 may be a procedure such as transmitting data to the BS 110. However, And the data transmission / reception with the base station. For example, when the wireless communication system is FDD, the UE2 122 receives data from the base station 110 through the downlink frequency band. In the flow of the D2D communication, the UE1 120, Lt; / RTI > Alternatively, when the wireless communication system is TDD, data is received from the base station 110 through the downlink subframe. In the D2D communication flow, data is received from the UE1 120 through the uplink subframe.

UE2 122 that has received the data may transmit ACK / NACK to UE1 120 via PUCCH or PHICH in order to inform UE1 120 of data reception (S214). The UE1 120 that has not received the data or has received the NACK response can retransmit the data to the UE2 122 via the PUSCH (S216).

Figure 2 is an example of resource allocation and data transmission for D2D terminals. Data may be transferred between the D2D terminals according to another flow. Some steps may be omitted, new steps may be added, resource allocation may be made through other steps, or data transmission may be made. For example, in a system employing a fully-controlled D2D mode, the BS can control all the resources allocated to the UEs as shown in FIG. 2. However, in the relaxed controlled D2D mode controlled D2D mode), after the D2D UE establishes the connection, the interference of the BS can be minimized or the communication between the UEs can be performed without interference of the BS.

The present invention provides a method for UE2 122 to transmit an ACK / NACK to UE1 120 in response to UE1 120 transmitting data to UE2 122. [ 2, the UE1 120 transmits data to the UE2 122 through the PUSCH (S212), and the UE2 122 transmits ACK / NACK to the UE1 120 via the PUCCH or PHICH RTI ID = 0.0 > S214) < / RTI > However, the flow of FIG. 2 may be an example flow for one embodiment of the present invention, but the present invention is not limited thereto.

Hereinafter, UE2 120 that transmits data in D2D communication and receives ACK / NACK is referred to as UE2 122, and UE2 122 receives data and transmits ACK / NACK. However, this is for convenience of explanation, and both UEs UE1 and UE2 can transmit / receive data and can transmit / receive ACK / NACK in the same or different manner.

1, in the communication between the BS 110 and the MSs 120 and 122, for example, in the communication between the BS 110 and the MS 120, the BS 110 and the MS 120 transmit PHICH Indicator Channel) and ACK / NACK through PUCCH. A control channel or a data channel scheme between a base station and a terminal for a control channel or a data channel for data transmission and reception of a D2D terminal may be applied to minimize a system change according to D2D in a wireless communication system. Accordingly, the present invention provides a method of transmitting an ACK / NACK using a PHICH resource or a PUCCH resource.

First, an ACK / NACK is transmitted / received through the PHICH in the communication between the base station 110 and the terminal 120.

In a wireless communication system, a base station transmits a reception of uplink data transmission through a PUSCH of a UE through a PHICH.

At this time, the PHICH resource is determined by the PHICH group (PHICH group) and the PHICH sequence. Each PHICH group is composed of 8 orthogonal codes for a subframe using a normal CP (Cyclic Prefix), and 4 orthogonal codes for a subframe using an extended CP. Each cell determines the total amount of PHICH resources by selecting the number of PHICH groups, and performs PHICH resource management through selection of a PHICH group and a PHICH sequence to transmit ACK / NACK to each terminal.

For FDD systems, the number of PHICH groups is

, And in the case of TDD systems, the number of PHICH groups is

Which uses PHICH resources of different sizes in each subframe.

Is defined by Equation (1)

The value is determined according to the subframe number i and the uplink-downlink setting, as shown in Table 1. [ In Equation (1)

Is the number of resource blocks defined in the downlink band,

Has a value of {1/6, 1/2, 1, 2}, which is a factor shared by the UE and the base station through high layer signaling.

[Equation 1]

[Table 1]

The PHICH resource that performs ACK / NACK reporting on the PUSCH is a PHICH Group Index (PHICH Group Index) calculated in the PHICH index of Equation (2)

) And a PHICH sequence index (PHICH Sequence Index,

) Value (index).

&Quot; (2) "

The PHICH sequence index has a value of 0 to 7 or 0 to 3 according to the type of the orthogonal sequence and can be applied as shown in Table 2 below.

[Table 2]

3, 25 resource blocks (RBs) are used in the uplink and downlink,

when

And

&Lt; / RTI > table for the PHICH group index and the sequence index determined by the value of the PHICH group index.

In Fig. 3, the PRB on the vertical axis

CS on the horizontal axis represents

. E.g,

Is 2,

Is 0, the PHICH group index (

) Is 2, and the PHICH sequence index (

) Becomes 1.

The present invention provides a way for the D2D terminal to utilize PHICH resources for such ACK / NACK.

FIG. 4 shows that control channels and data channels are transmitted in D2D communication.

Referring to FIG. 4, uplink scheduling information for a UE UE1 120 that transmits data in D2D communication is transmitted from a Node B 110 to a UE 120 through a PDCCH. Referring to FIG. 2, this corresponds to the step S208. In the FDD system, the time interval between the uplink control information and the data transmission may be 4ms (4 subframe intervals).

The PDCCH transmitted to UE1 120 may also be transmitted to UE2 122. [ The PDCCH including the uplink scheduling information is transmitted and all the D2D transmitting / receiving terminals acquire the corresponding control information. At this time, the D2D terminals can search not only the PDCCH search space of the D2D terminals but also the PDCCH search fields of other terminals having the D2D connection setting. Or the PDCCH may be transmitted using a space that the D2D transmitting / receiving terminal can simultaneously search.

The UEs (UE1, 120) receiving the PDCCH including the UL scheduling information and transmitting the PUSCH can receive the ACK / NACK information through the PHICH. The UEs 2 and 122 receiving the PUSCH can transmit ACK / NACK information through the PHICH.

At this time, the radio resource of the PHICH transmitted / received may be the same method as the PHICH resource allocation method used for ACK / NACK transmission between the BS and the MS.

As described above, the PHICH resource includes the PHICH Group Index (PHICH Group Index) calculated in the PHICH index of Equation (2)

) And a PHICH sequence index (PHICH Sequence Index,

) Value (index).

In the PHICH resource utilization method for ACK / NACK, UE1 120, which transmits data and receives ACK / NACK through PHICH, performs communication according to the same procedure as that of transmitting data to the base station and receiving PHICH . However, in the case of UE2 122, when data is received from the base station, ACK / NACK is transmitted through the PHICH and data is received from the D2D terminal (UE1, 120), unlike ACK / NACK is transmitted through the PUCCH .

When the D2D UEs are located in different cells, the PHICH group index and the PHICH sequence index information for PHICH resource calculation or the PHICH group index and the PHICH sequence index

May be communicated to the two terminals UE1 and UE2 via higher layer signaling (e.g., Radio Resource Control (RRC)).

In the above, a method of transmitting ACK / NACK for data transmission through the PHICH in the D2D communication has been described. Hereinafter, a method of transmitting ACK / NACK for data transmission through the PUCCH in the D2D communication will be described.

In case of UEs (UEs) 120 transmitting data, uplink scheduling information is received so that the procedure and channel used for communication with the base station are the same, and data is transmitted accordingly, and PHICH is received by ACK / It will be advantageous in terms of compatibility.

On the other hand, in the case of the UEs (UEs) 122 receiving the data, receiving the downlink scheduling information, receiving the data, and transmitting the PUCCH by ACK / NACK thereto, And in a similar manner to the channel.

If the method of transmitting the ACK / NACK through the PHICH corresponds to the former, a method of transmitting the ACK / NACK through the PUCCH to be described later corresponds to the latter.

First, transmission and reception of ACK / NACK through the PUCCH in the communication between the base station 110 and the terminal 122 will be described.

5 is a flowchart of downlink transmission and uplink transmission in the wireless communication system of FIG.

Referring to FIG. 5, the BS 110 may perform downlink transmission (S510) to the MS 122. FIG. The BS 110 transmits downlink control information such as a Physical Downlink Shared Channel (PDSCH), which is a primary physical channel for unicast transmission, and scheduling required for PDSCH reception, (Physical Downlink Control Channel (PDCCH)) for transmitting scheduling grant information for transmission in a physical uplink shared channel (PUSCH), for example.

Referring to FIG. 5, the UE2 122 may perform uplink transmission (S520) to the BS 110. FIG. The UE2 122 transmits a scheduling request (SR) to the Node B 110 through an uplink control channel (e.g., a Physical Uplink Control CHannel (PUCCH)), an ACK / NACK and a report of a UE related to a downlink channel state and can transmit uplink data through an uplink data channel (for example, PUSCH (Physical Uplink Shared CHannel)).

At this time, the PUCCH can support various formats as shown in Table 3 below.

[Table 3]

The PUCCH format 1 / 1a / 1b may be used for SR (scheduling request) and ACK / NACK (HARQ-ACK / NACK) transmission. The PUCCH format 2 / 2a / 2b may be used for CQI (Channel Quality Indicator) / PMI (Precoding Matrix Indicator) / RI (Rank Indication) transmission. The PUCCH format 3 can be used for a plurality of HARQ-ACK / NACK transmissions.

All PUCCH formats have a cell-specific cyclic shift (CS)

Lt; / RTI >

May be defined as Equation (3) according to the symbol number (l) and the slot number (ns).

&Quot; (3) "

In Equation 3,

Corresponds to the total number of SC-FDMA symbols used per slot in the uplink. c (i) is a pseudo-random sequence, the initial value (cinit) is the cell ID

)to be. Therefore, the cyclic delay of the PUCCH can be determined by the cell ID.

FIG. 6 illustrates a scheme in which control information according to each PUCCH format is mapped to a resource block (RB).

The physical resource block used for transmission of the PUCCH as shown in FIG. 6 may be defined as the following Equation 4 in the slot ns.

&Quot; (4) "

In Equation 4,

Depends on the PUCCH format.

In the case of Formats 1 and 1a, 1b

silver

_ego,

In the case of formats 2, 2a and 2b

silver

, And in the format 3

silver

to be.

In Equation (4), nPRB is a physical resource block number,

Is the number of uplink resource blocks,

Is the number of subcarriers in one resource block.

Is a value transmitted through upper layer signaling,

Represents a resource block available for PUCCH format 2 / 2a / 2b transmission in each slot.

Represents the number of cyclic delays used for the PUCCH format 1 / 1a / 1b in the resource block in which the PUCCH formats 1 / 1a / 1b and 2 / 2a / 2b are mixed,

Lt; / RTI >

Is transmitted via upper layer signaling. The orthogonal resources used for transmission of the PUCCH formats 1 / 1a / 1b, 2 / 2a / 2b, and 3 are

And

Lt; / RTI >

Referring to Equation (4), at the edge of the uplink bandwidth

Are used for PUCCH format 2 / 2a / 2b transmission, and information

) Is transmitted through uplink signaling. 1 / 1a / 1b and 2 / 2a / 2b are mixed and used in the resource block for PUCCH format 2 / 2a / 2b transmission, and the PUCCH format 1 / 1a / 1b A parameter indicating how many orthogonal resources for

. The resource blocks are then used for PUCCH format 1 / 1a / 1b transmissions.

In Equation (4), the index of a resource block for only PUCCH format 1 / 1a / 1b is divided into two slots in one subframe

about

As many

It is increased by one by one. That is, for each specific subframe to which the PUCCH is mapped, a resource index (hereinafter referred to as " resource index ") in two resource blocks of one subframe consisting of two slots

The total number of

, Which means the total number of resources having orthogonality in the resource block.

In other words,

Is an antenna index (

) Is a parameter indicating the index of the orthogonal resource for all orthogonal resources used for the PUCCH format 1 / 1a / 1b,

Is a parameter indicating the index of the orthogonal resource for all orthogonal resources used in one resource block.

The PUCCH resource mapping for the HARQ ACK / NACK feedback for the corresponding PDSCH reception of the UE, in which the PDSCH allocation information for the UE is transmitted through the downlink scheduling information allocated to the control region of the resource block, (RRC parameter) and a Control Channel Element (CCE) index to which the corresponding downlink scheduling information is transmitted, as shown in Equations (5) and (6)

&Quot; (5) "

&Quot; (6) "

Equation (5) and Equation (6) show Equation (5) and Equation (6) are PUCCH resources for HARQ ACK / NACK feedback at antenna port 0 and antenna port 1, respectively,

Quot;

Denotes a minimum CCE index value to which the corresponding downlink scheduling information is transmitted, and this can be dynamically defined.

Specific parameters set by upper layer signaling (e.g., RRC signaling) to serve as an offset for PUCCH format 1 / 1a / 1b resource allocation to determine the point at which a dynamically allocated PUCCH region is to start have.

As described above, in the area where the PUCCH format 2 / 2a / 2b and the PUCCH format 2 / 2a / 2b and 1 / 1a / 1b are mixed, the resource block is semi-static through the upper layer signaling, And the resource block in the area for PUCCH format 1 / 1a / 1b can be determined dynamically. 4, the uplink transmission resources are classified into a quasi-static setting region 610, a dynamic setting region 620 where the PUCCH format 1 / 1a / 1b can be set, and a PUSCH region 630 .

However, the PUCCH resource mapping method according to Equations (3) and (4) can be applied to HARQ ACK / NACK (PUCCH) through a PUCCH format 1a / 1b of a terminal in which one serving cell is set in a frame structure type 1 (FDD) PUCCH resource mapping method for transmission. In addition, the PUCCH resource mapping rule for a terminal on which one or more serving cells are established (i.e., a UE to which carrier aggregation is applied) is a function of a minimum CCE index and a higher layer parameter similar to the above- Or sets a plurality of candidate PUCCH resource values through upper layer signaling in advance and sets a PUCCH resource value to be used among the candidate PUCCH resource values through a 'TPC command for PUCCH' information region of actual downlink scheduling information An ARI (ACK / NACK Resource Indication) scheme indicating a resource may be used.

Reception of ACK / NACK through the PUCCH between the UEs (UE1, 120) for transmitting data in D2D communication and the UEs (UE2, 122) for receiving data will be described.

The terminal UE2 122 receiving the data can receive the PDCCH transmitted to the UE1 120 as well as the UE2 122, as described with reference to Fig. At this time, control information included in the PDCCH can be used as uplink scheduling information for UE1 120 and downlink scheduling information for UE2 122. [ The UE1 120 and the UE2 122 can receive such a PDCCH by searching not only their own search space but also the other's PDCCH search space or a space where the base station can search both terminals UE1 and UE2 The UE1 120 and the UE2 122 may receive a common PDCCH by transmitting the PDCCH using the PDCCH (first method).

Alternatively, UE1 120 may receive uplink scheduling information through a subframe ahead of a subframe in which the PUSCH is transmitted, and UE2 122 may receive uplink scheduling information in the same subframe as the PUSCH to which the PUSCH is transmitted And receive downlink scheduling information through a subframe of time (second method).

FIG. 7 shows that uplink scheduling information and downlink scheduling information are independently transmitted in D2D communication.

Referring to FIG. 7, uplink scheduling information is transmitted to the UE1 120 in a subframe 710 ahead of the subframe 730 in which the PUSCH is transmitted, and a subframe 730 in which the PUSCH is transmitted And downlink scheduling information may be transmitted to the UE2 122 in the subframe 720 of the same time.

In order to transmit and receive ACK / NACK through the PUCCH, both the UE1 120 for transmitting data and the UE2 122 for receiving data must know the PUCCH resource region. When the PUCCH determines resources to be transmitted as shown in Equations (5) to (6), the two terminals UE1 and UE2

Value and

You must know the value. At this time,

The UEs UE1 and UE2 can share information through higher layer signaling. By the way,

If UE1 120 follows the second method described above with the minimum CCE index value for which the downlink scheduling information is transmitted,

There is a problem that is difficult to grasp the value.

On the other hand, according to the first method,

Is a minimum CCE index value to which downlink scheduling information (uplink scheduling information in the case of UE1) transmitted in a subframe preceding a subframe in which the PUSCH is transmitted is transmitted, and N (N is a natural number, for example, N = 4 Lt; RTI ID = 0.0 >

Value is used to perform downlink scheduling information transmission in the corresponding subframe, a problem of PUCCH resource collision may occur when transmitting ACK / NACK for the downlink data transmissions.

FIG. 8 shows an example in which collision of PUCCH resources occurs.

Referring to FIG. 8, downlink scheduling information for UE2 122 is transmitted in a subframe 810 that precedes subframe 830 where data transmission of UE1 120 is performed, and data transmission of UE1 120 is transmitted The downlink scheduling information for the other UE or the downlink scheduling information for the UE2 122 for data transmission from the Node B to the UE2 122 may be transmitted in the subframe 820 at the same time as the subframe 830 .

At this time, the minimum CCE index of the resource to which the downlink scheduling information is transmitted in the 810 subframe and the minimum CCE index of the resource to which the downlink scheduling information is transmitted in the 820 subframe may be the same. For this reason

Values may be the same, and

The collision may occur between different PUCCH channels.

The present invention provides a method of transmitting an ACK / NACK through a PUCCH in D2D communication, using a PUCCH resource offset parameter.

The base station transmits a PUCCH resource offset parameter

Value to the D2D terminals UE1 and UE2 through higher layer signaling (e.g., RRC) in a UE-specific manner.

The UE-specific PUCCH offset (

) May be reused. Such

Can specifically indicate the start time of the PUCCH resource for ACK / NACK transmission in a UE-specific manner.

The present invention also provides a method for transmitting ACK / NACK over PUCCH in D2D communication,

As shown in FIG.

Is a physical resource block (PRB) index of a band in which PUSCH transmission is performed as described in Equation (2).

&Quot; (7) "

&Quot; (8) "

Equation (7)

Wow

use with

, And Equation (8) is a formula for indicating

Wow

use with

Quot; is < / RTI >

Is a value related to a resource to which data is transmitted in D2D communication, and is a value that both terminals UE1 and UE2 of D2D communication recognize,

or

Is a value that both UEs UE1 and UE2 can share through upper layer signaling, so that both the UE2 transmitting the ACK / NACK through the PUCCH and the UE1 receiving the PUCCH resource can recognize the PUCCH resource .

In the method of transmitting and receiving ACK / NACK in the D2D communication according to the embodiments of the present invention, the ACK / NACK information may be transmitted together with the base station. For example, in a method of transmitting an ACK / NACK through a PHICH, a base station can receive a PHICH. In addition, in the method of transmitting ACK / NACK through the PUCCH, the base station can receive the PUCCH.

In the communication between the base station and the UE, the uplink has non-adaptive HARQ characteristics. Since the non-adaptive HARQ reuses the space in which data is first transmitted when retransmitting the data, the BS does not need to instruct the resource allocation through the additional PDCCH.

In order to use the characteristics of non-adaptive HARQ for D2D communication, the base station must be able to acquire indication information on whether data is received between D2D terminals. Since the resources initially allocated for D2D communication can be reused when the D2D data is not received, the scheduling for the other UEs should not be performed for the corresponding resources. To do so, the base station must determine whether data is received in the D2D communication do.

In an embodiment of the present invention, when the data receiving terminal UE2 transmits ACK / NACK information to the data transmitting terminal UE1, the base station can receive the ACK / NACK information.

The present invention provides a method for transmitting ACK / NACK through PHICH or PUCCH in D2D communication.

The method of transmitting the ACK / NACK through the PUCCH according to the embodiment of the present invention is characterized in that even when the uplink / downlink control signal for D2D communication is transmitted at one time, the PUCCH resource conflict with another terminal that does not use D2D communication Can be avoided. Also, when the uplink / downlink for D2D communication is independently transmitted, the resources of the PUCCH are divided into a PRB index

), It is possible to solve the problem that the ACK / NACK receiving terminal UE1 does not recognize the CCE index of the downlink scheduling information of the UE2 transmitting the ACK / NACK.

9 is a flowchart illustrating an ACK / NACK transmission method of a UE according to an embodiment of the present invention.

A terminal is a terminal that receives data from another terminal, and terminals and other terminals can perform D2D (Device to Device) communication. As described with reference to FIG. 2, the UE and the UE may perform data transmission / reception through scheduling request transmission / reception via PUCCH, uplink scheduling information transmission / reception for BSR reporting via PDCCH, BSR transmission / reception through PUSCH .

9, the UE receives uplink or downlink scheduling information for data reception from another UE (S910), and receives data through an allocated data channel according to the uplink or downlink scheduling information And transmitting ACK / NACK for data reception through a Physical Uplink Indicator Channel (PHICH) or a Physical Uplink Control Channel (PUCCH) (S920).

As described with reference to step S208 of FIG. 2, the base station can transmit uplink scheduling information so that other terminals can transmit data to the terminal. Such uplink scheduling information can be received by not only other terminals that transmit data but also terminals that receive data.

The uplink scheduling information is transmitted through the PDCCH. The terminal receiving the data blinds or searches for a PDCCH search space of another terminal that transmits data to the other terminal to which the base station transmits data And receive uplink scheduling information for transmission.

Alternatively, the base station may transmit the PDCCH including the uplink scheduling information through the PDCCH search space of the UE receiving the data. In this case, the other terminal transmitting the data may receive the uplink scheduling information by blind decoding or searching the PDCCH search space of the terminal receiving the data.

Alternatively, the base station may transmit the PDCCH through a common search space between a terminal receiving data and another terminal transmitting data, so that both terminals can receive UL scheduling information.

The UE receives data through an allocated data channel (e.g., PUSCH) according to uplink scheduling information, and transmits ACK / NACK for data reception through another PHICH to another UE that has transmitted the data.

In the method of transmitting ACK / NACK through the PHICH, the base station can receive the PUSCH from the terminal and use the PHICH defined as ACK / NACK for the ACK / NACK.

The resource for performing the ACK / NACK report on the PUSCH received from the BS by the BS is expressed by a PHICH Group Index (PHICH Group Index) calculated in the PHICH index of Equation (2)

) And a PHICH sequence index (PHICH Sequence Index,

) Value (index). According to equation (2)

Wow

Information used to determine < RTI ID = 0.0 >

Is information that can be recognized by each of the UEs when the UE transmitting data and the UE receiving the data share uplink scheduling information and are located in the same cell.

When the two UEs are located in different cells, the PHICH group index and the PHICH sequence index information for PHICH resource calculation or the PHICH group index and PHICH sequence index calculation sub-

May be delivered to the two terminals via higher layer signaling (e.g., Radio Resource Control (RRC)).

The UE may receive data through an allocated data channel (e.g., PUSCH) according to downlink scheduling information, and may transmit an ACK / NACK with respect to reception of data through the PUCCH to another UE that has transmitted the data.

A subframe in which downlink scheduling information is received may be a subframe of a time preceding the subframe in which the data channel is received, or may be a subframe of the same time.

The radio resource of the PUCCH can be determined by the minimum CCE index and the offset parameter to which the downlink scheduling information is transmitted, as shown in Equations (5) and (6).

Alternatively, the radio resource may be determined using the lowest index of the resource block on which the data channel is received in place of. In addition, as the offset parameter, the PUCCH resource offset parameter transmitted to the UEs for D2D communication through the upper layer signaling

&Lt; / RTI >

If the above two alternative parameters are used, the resources for the PUCCH transmission

May follow Equation (8) or Equation (9). In other words,

, Where < RTI ID = 0.0 >

Is the lowest index of the resource block on which the data channel is received,

Is a PUCCH resource offset parameter transmitted through upper layer signaling to another terminal that transmits data from a base station and a terminal that receives data.

The PHICH or PUCCH transmitted by the MS may be received by the BS as well as other MSs transmitting the data. The UE and the other UE can perform D2D communication using the characteristics of non-adaptive HARQ. If the base station receives the PHICH or PUCCH as the ACK / NACK feedback and the data reception is not performed, The mobile station can receive the PHICH or the PUCCH as the ACK / NACK feedback so as not to schedule the corresponding space for another UE so that data can be transmitted and received.

10 is a flowchart illustrating a method of receiving an ACK / NACK of a base station according to another embodiment of the present invention.

In the case where the terminal and another terminal perform D2D communication, the base station can control or monitor the D2D communication by transmitting / receiving control information to both terminals.

As described with reference to FIG. 2, the UE and the UE can perform data transmission / reception through scheduling request transmission / reception via PUCCH, uplink scheduling information transmission / reception for BSR reporting via PDCCH, and BSR transmission / reception through PUSCH , And the PUCCH, PDCCH, and PUSCH may be communication between the other terminal and the base station transmitting data.

Referring to FIG. 10, a base station transmits uplink or downlink scheduling information for data transmission and reception to a subscriber station (S1010), and transmits a data channel allocated according to uplink or downlink scheduling information And receiving a PUCCH for transmitting ACK / NACK for data reception after receiving data from the terminal (S1020).

The step of receiving an ACK / NACK from the UE (step S 1020) is a step required to support the D2D communication so that the UE transmitting and receiving data and other UEs can perform D2D communication using the characteristics of non-adaptive HARQ, May be omitted.

In other words, the UE and another UE can perform D2D communication using the characteristics of non-adaptive HARQ. If the base station receives the PHICH or PUCCH as ACK / NACK feedback and data reception is not performed, The mobile station can receive the PHICH or PUCCH as the ACK / NACK feedback in order not to schedule the corresponding space for another terminal so that data can be transmitted and received. However, the step S1020 may be omitted if there is no necessity as in the case of not using the characteristic of non-adaptive HARQ.

The base station may transmit scheduling information to each of the terminals to allocate a data channel through which data can be transmitted between the two terminals of the D2D communication or may transmit scheduling information to all of the terminals as transmission of one time of scheduling information .

First, a base station can transmit common uplink scheduling information to two terminals. According to the uplink scheduling information, other UEs that transmit data through the allocated data channel can transmit data. The UE receiving the data can recognize the resource allocated to the data channel according to the uplink scheduling information and receive the data transmitted from the UE through the UE.

At this time, a method of transmitting ACK / NACK through the PHICH may be the same as a method in which the BS receives the PUSCH from the MS and transmits the PHICH as ACK / NACK to the MS.

) And a PHICH sequence index (PHICH Sequence Index,

) Value (index). According to equation (2)

Wow

Information used to determine < RTI ID = 0.0 >

,

The base station can transmit scheduling information independently to the two terminals. The resource allocation information for the data channel can be transmitted to the other terminal through which the data is transmitted through the uplink scheduling information. As another scheduling information, the base station allocates resources for the data channel to the terminal receiving the data through the downlink scheduling information Information can be transmitted.

The subframe in which the UL scheduling information is transmitted may be a subframe preceding the subframe in which the data channel is transmitted and received. The subframe in which the downlink scheduling information is transmitted may be a subframe of a time preceding the subframe in which the data channel is transmitted and received, or may be a subframe of the same time.

Radio resources of PUCCH

The minimum CCE index < RTI ID = 0.0 > (k) < / RTI &

And offset parameters

Lt; / RTI >

Or radio resources

silver

The lowest index of the resource block on which the data channel is received

&Lt; / RTI > Further,

The PUCCH resource offset parameter < RTI ID = 0.0 >

&Lt; / RTI >

May follow Equation (8) or Equation (9). In other words,

, Where < RTI ID = 0.0 >

11 is a block diagram of a UE according to another embodiment of the present invention.

11, the terminal 120 may include a controller 121, a transmitter 122, a receiver 123, and the like.

The control unit 121 may control the transmitting unit 122 and the receiving unit 123 and may perform a series of control operations according to the embodiment of the present invention.

The receiving unit 123 may receive uplink or downlink scheduling information for data transmission / reception from / to the base station, and may receive data through the allocated data channel according to the uplink or downlink scheduling information.

The transmission unit 122 may transmit an ACK / NACK for data reception from another terminal through a Physical Upligh Indicator Channel (PHICH) or a Physical Uplink Control Channel (PUCCH).

) And a PHICH sequence index (PHICH Sequence Index,

) Value (index). According to equation (2)

Wow

Information used to determine < RTI ID = 0.0 >

,

Radio resources of PUCCH

The minimum CCE index < RTI ID = 0.0 > (k) < / RTI &

And offset parameters

Lt; / RTI >

Or radio resources

silver

The lowest index of the resource block on which the data channel is received

&Lt; / RTI > Further,

The PUCCH resource offset parameter < RTI ID = 0.0 >

&Lt; / RTI >

May follow Equation (8) or Equation (9). In other words,

, Where < RTI ID = 0.0 >

12 is a block diagram of a base station according to another embodiment of the present invention.

12, the base station 110 may include a controller 111, a transmitter 112, a receiver 113, and the like.

The control unit 111 may control the transmission unit 112 and the reception unit 113 and may perform a series of control operations according to the embodiment of the present invention.

The transmission unit 112 may transmit uplink or downlink scheduling information for data transmission and reception to a terminal receiving data.

The receiving unit 113 may receive a PUCCH for transmitting an ACK / NACK for data reception after the UE receives the data through the allocated data channel according to the uplink or downlink scheduling information.

The transmitting unit 112 may transmit scheduling information to each of the UEs to allocate a data channel through which data can be transmitted between the two UEs in the D2D communication or may transmit scheduling information Can be transmitted.

First, the transmitter 112 can transmit common UL scheduling information to the two terminals. According to the uplink scheduling information, other UEs that transmit data through the allocated data channel can transmit data. The UE receiving the data can recognize the resource allocated to the data channel according to the uplink scheduling information and receive the data transmitted from the UE through the UE.

The uplink scheduling information is transmitted through the PDCCH. The uplink scheduling information is transmitted through the PDCCH. The terminal receiving the data blindly decodes or searches the PDCCH search space of another UE transmitting data, And receive uplink scheduling information for the UE.

Alternatively, the transmission unit 112 may transmit the PDCCH including the uplink scheduling information through the PDCCH search space of the UE receiving the data. In this case, the other terminal transmitting the data may receive the uplink scheduling information by blind decoding or searching the PDCCH search space of the terminal receiving the data.

Alternatively, the transmitter 112 may transmit the PDCCH through a common search space between a terminal receiving data and another terminal transmitting data, so that both terminals can receive UL scheduling information.

) And a PHICH sequence index (PHICH Sequence Index,

) Value (index). According to equation (2)

Wow

Information used to determine < RTI ID = 0.0 >

,

The transmission unit 112 can transmit scheduling information independently to the two terminals. The resource allocation information for the data channel can be transmitted to the other terminal through which the data is transmitted through the uplink scheduling information. As another scheduling information, the base station allocates resources for the data channel to the terminal receiving the data through the downlink scheduling information Information can be transmitted.

Radio resources of PUCCH

The minimum CCE index < RTI ID = 0.0 > (k) < / RTI &

And offset parameters

Lt; / RTI >

Or radio resources

silver

The lowest index of the resource block on which the data channel is received

&Lt; / RTI > Further,

The PUCCH resource offset parameter < RTI ID = 0.0 >

&Lt; / RTI >

May follow Equation (8) or Equation (9). In other words,

, Where < RTI ID = 0.0 >

While the present invention has been described in connection with what is presently considered to be the most practical and preferred embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. That is, within the scope of the present invention, all of the components may be selectively coupled to one or more of them. In addition, although all of the components may be implemented as one independent hardware, some or all of the components may be selectively combined to perform a part or all of the functions in one or a plurality of hardware. As shown in FIG. The codes and code segments constituting the computer program may be easily deduced by those skilled in the art. Such a computer program can be stored in a computer-readable storage medium, readable and executed by a computer, thereby realizing an embodiment of the present invention. As a storage medium of the computer program, a magnetic recording medium, an optical recording medium, or the like can be included.

It is also to be understood that the terms such as " comprises, "" comprising," or "having ", as used herein, mean that a component can be implanted unless specifically stated to the contrary. But should be construed as including other elements. All terms, including technical and scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs, unless otherwise defined. Commonly used terms, such as predefined terms, should be interpreted to be consistent with the contextual meanings of the related art, and are not to be construed as ideal or overly formal, unless expressly defined to the contrary.

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 falling within the scope of the same shall be construed as falling within the scope of the present invention.

Claims

A method for transmitting an ACK / NACK for data reception by a UE receiving data from another UE,
Receiving uplink or downlink scheduling information for transmitting and receiving data from a base station;
Receives the data through an allocated data channel according to the uplink or downlink scheduling information, and transmits an ACK / NACK for the data reception through a Physical Uplink Indicator Channel (PHICH) or a Physical Uplink Control Channel (PUCCH) And transmitting the ACK / NACK message.

The method according to claim 1,
Wherein the lowest index of the resource block in which the data channel is received is used as a resource decision element in the PUCCH resource mapping.

The method according to claim 1,
The orthogonal resource for the PUCCH transmission

The

Lt; / RTI >

Wherein the PUCCH resource offset parameter is a PUCCH resource offset parameter transmitted from the base station to the other terminal through the upper layer signaling.

A base station method for receiving an ACK / NACK for data reception from a terminal receiving data from another terminal,
Transmitting uplink or downlink scheduling information for data transmission and reception to the mobile station;
Receiving from the MS a PUCCH (Physical Uplink Control Channel) for receiving ACK / NACK for data reception after the MS receives the data through an allocated data channel according to the uplink or downlink scheduling information / RTI >

5. The method of claim 4,
Wherein the uplink scheduling information is transmitted through a common search space of the UE and the UE.

5. The method of claim 4,
Wherein the lowest index of a resource block in which the data channel is received by the terminal is used as a resource determination element in the PUCCH resource mapping of the terminal.

5. The method of claim 4,
The orthogonal resource for the PUCCH reception

The

Lt; / RTI >

Wherein the PUCCH resource offset parameter is a PUCCH resource offset parameter that the BS transmits to the other terminal through the upper layer signaling.

A terminal for receiving data from another terminal and transmitting an ACK / NACK for the data reception,
A receiver for receiving uplink or downlink scheduling information for transmitting and receiving data from a base station and receiving the data through an allocated data channel according to the uplink or downlink scheduling information;
And a transmitter for transmitting an ACK / NACK for the data reception through a Physical Uplink Indicator Channel (PHICH) or a Physical Uplink Control Channel (PUCCH).

9. The method of claim 8,
Wherein the lowest index of the resource block in which the data channel is received is used as a resource decision element in the PUCCH resource mapping.

9. The method of claim 8,
The orthogonal resource for the PUCCH transmission

The

Lt; / RTI >

Is a PUCCH resource offset parameter transmitted from the base station to the other terminal through the upper layer signaling.

A base station for receiving ACK / NACK for data reception from a terminal receiving data from another terminal,
A transmitter for transmitting uplink or downlink scheduling information for data transmission and reception to the MS,
A receiving unit for receiving, from the UE, a Physical Uplink Control Channel (PUCCH) for receiving ACK / NACK for data reception after the UE receives the data through an allocated data channel according to the uplink or downlink scheduling information; / RTI >

12. The method of claim 11,
Wherein the transmitter transmits the UL scheduling information through a common search space of the UE and the UE.

12. The method of claim 11,
Wherein a lowest index of a resource block in which the data channel is received by the terminal is used as a resource decision element in the PUCCH resource mapping of the terminal.

12. The method of claim 11,
The orthogonal resource for the PUCCH reception

The

Lt; / RTI >

Is a PUCCH resource offset parameter transmitted by the base station through the upper layer signaling to the other terminal and the terminal.