WO2014171692A1

WO2014171692A1 - Find signal transmission/reception method for terminal to terminal communication and apparatus therefor

Info

Publication number: WO2014171692A1
Application number: PCT/KR2014/003227
Authority: WO
Inventors: 노상민; 곽용준; 정경인; 지형주; 김윤선; 최승훈
Original assignee: 삼성전자 주식회사
Priority date: 2013-04-19
Filing date: 2014-04-15
Publication date: 2014-10-23
Also published as: KR20140125633A

Abstract

Disclosed are a find signal transmission/reception method for terminal to terminal communication and an apparatus therefor. A transmission terminal generates a first find signal and a second find signal for transmitting to a reception terminal based on the service related information provided through terminal to terminal communication, assigning the first find signal and the second find signal respectively to a predetermined first find signal transmission resource and a second find signal transmission resource determined from the first find signal transmission resource, and transmitting the first find signal and the second find signal to the reception terminal.

Description

Method and apparatus for transmitting and receiving discovery signal for terminal to terminal communication

The present invention relates to a method and apparatus for transmitting and receiving a discovery signal for terminal-to-terminal communication. More particularly, the present invention relates to a discovery signal for a terminal performing terminal-to-terminal communication to recognize another terminal and performing an operation related to terminal-to-terminal communication. It relates to a method of generating and transmitting.

The asynchronous cellular mobile communication standardization organization 3GPP (3 ^rd Generation Partnership Project) in the (Long Term Evolution) the old base station and as well as the wireless communication between the terminal station or the wireless communication between devices, i.e. D2D (Device-to-Device) communication LTE A discussion is underway to support the system specification.

For D2D communication discussed in 3GPP, one D2D UE needs to discover other D2D UEs around it. For this purpose, each D2D UE transmits a discovery signal. The discovery signal is used by other D2D terminals to recognize that the D2D terminal is present in the vicinity.

In order to utilize the discovery signal, for example, time and frequency resources for transmitting and receiving the discovery signal are determined in an orthogonal frequency division multiplexing (OFDM) based transmission and reception system. Each D2D terminal in the system transmits a discovery signal through each time and frequency resource allocated for transmitting its own discovery signal in time and frequency resources, and detects discovery signals transmitted by other D2D terminals in other discovery signal transmission / reception resources Try. As such, the discovery signal transceivable resource is set to accommodate a large number of D2D terminals existing in the system.

Here, each time and frequency resource allocated to each D2D user equipment may correspond to D2D user equipment identification information in the system, such as a corresponding D2D user equipment ID. After attempting to detect a discovery signal of another D2D UE, the D2D UEs determine whether a D2D UE corresponding to the corresponding time and frequency resource exists in the vicinity according to whether a detection signal of each time and frequency resource exists. In this case, the discovery signal may have a relatively simple structure such as a reference signal, a sequence, or a single tone.

Meanwhile, as described above, the discovery signal may provide the simplest form of discovery related information through time and frequency resource allocation and whether a discovery signal exists in the corresponding resource, but the discovery signal itself is designed to include discovery related information bits. For example, information useful for the D2D service (hereinafter, referred to as 'D2D service related information') may be provided during the discovery process.

As D2D service related information, an ID for D2D (hereinafter, referred to as 'D2D ID') in a wireless communication system may be used as an example. The D2D ID is a unique ID of each D2D terminal, which enables the D2D terminal to be distinguished from the system. The second piece of information is an Application ID. Application ID is a unique ID (for example, KakaoTalk or Facebook) used in the D2D terminal to distinguish the applications used in the terminal. The third piece of information is an application-specific user ID. Application-specific user ID is an ID given to a user for an application of the D2D terminal, and may be, for example, a user account or nickname of KakaoTalk or Facebook. For example, interest ID may be used as the fourth information. The interest ID is an ID indicating an application or user-defined user content / preference / need. As a simple example, an interest ID can be used to provide information such as "discount sales" or "accommodation notices."

As described above, when the D2D service-related information is included in the discovery signal, each D2D terminal user not only recognizes other D2D terminals present in the surroundings through the discovery process, but also the interest of each D2D terminal, the same application or interest as the own. It is possible to provide high-quality D2D service by acquiring more information such as the presence of a D2D device using an application, a D2D device having a specific alias or account of a specific application.

However, since the length of the various ID information described above will be tens or hundreds of bits or more, the discovery signal carrying ID bits may have a physical layer channel structure to which specific communication resources are allocated. In addition, channel coding or cyclic redundancy check (CRC) may be applied to ID bit information to ensure discovery signal reception performance of D2D UEs.

However, in the case of transmitting various D2D service-related information in the discovery signal to provide high-quality D2D service, dozens to hundreds of bits or more received from a considerable number of D2D terminals over most of the discovery signal transmission / reception resources Attempting to detect the discovery signals including the D2D service information puts a heavy burden on the D2D terminal receiving end.

In addition, since a required amount of D2D service information may vary according to a service type or quality, a plurality of discovery signal types may exist. Therefore, when designing a discovery signal, it is necessary to consider to include a variable amount of D2D service information in a specific set.

The present invention is derived to solve the above problems, an object of the present invention is to discover the discovery signal resource allocation, discovery signal detection method, including the discovery signal design for reducing the burden of the D2D terminal receiver when detecting the discovery signal And providing an apparatus.

An embodiment of the present invention for achieving the above technical problem is a method for transmitting a discovery signal of a transmitting terminal for terminal-to-terminal communication, and transmits to a receiving terminal based on information related to a service provided through the terminal-to-terminal communication. Generating a first discovery signal and a second discovery signal; Allocating the first discovery signal and the second discovery signal to a second discovery signal transmission resource determined from a preset first discovery signal transmission resource and the first discovery signal transmission resource; And transmitting the first discovery signal and the second discovery signal to the receiving terminal.

An embodiment of the present invention for achieving the above technical problem is a method for receiving a discovery signal of a receiving terminal for terminal-to-terminal communication, a service provided through the terminal-to-terminal communication through a first discovery signal transmission resource previously set Receiving a first discovery signal of a transmitting terminal generated based on information associated with the; Comparing the first discovery signal information of the transmitting terminal detected from the first discovery signal with the service related information of the receiving terminal previously stored; Determining a second discovery signal transmission resource from the first discovery signal transmission resource if the first discovery signal information of the transmitting terminal corresponds to service related information of the receiving terminal; Receiving a second discovery signal of the transmitting terminal through the second discovery signal transmission resource; Comparing second discovery signal information of the transmitting terminal and service related information of the receiving terminal detected from the second discovery signal; And when the second discovery signal information of the transmitting terminal corresponds to the service related information of the receiving terminal, performing the terminal to terminal communication operation with respect to the transmitting terminal.

In accordance with another aspect of the present invention, a discovery signal transmission apparatus of a transmitting terminal for terminal-to-terminal communication includes: a discovery signal transmitting unit transmitting the discovery signal to a receiving terminal; And generating a first discovery signal and a second discovery signal to be transmitted to the receiving terminal based on the information related to the service provided through the terminal-to-terminal communication, and transmitting a first discovery signal transmission resource and the first discovery signal which are preset. And a control unit for allocating the first discovery signal and the second discovery signal to a second discovery signal transmission resource determined from a resource, and controlling to transmit the first discovery signal and the second discovery signal to the receiving terminal. do.

In accordance with another aspect of the present invention, there is provided a discovery signal receiving apparatus of a receiving terminal for terminal-to-terminal communication, and a service provided through the terminal-to-terminal communication through a preset first discovery signal transmission resource. A discovery signal for receiving a first discovery signal of the transmitting terminal generated based on information associated with the second discovery signal and a second discovery signal of the transmitting terminal through a second discovery signal transmission resource determined from the first discovery signal transmission resource; Receiving unit; And comparing the first discovery signal information of the transmitting terminal detected from the received first discovery signal with the service related information of the receiving terminal stored in advance, so that the first discovery signal information of the transmitting terminal is the service related information of the receiving terminal. Corresponding to, the second discovery signal transmission resource is determined from the first discovery signal transmission resource, and the second discovery signal information of the transmitting terminal and the service related information of the receiving terminal detected from the received second discovery signal. And comparing the second discovery signal information of the transmitting terminal with the service related information of the receiving terminal, and controlling the terminal-to-terminal communication operation with respect to the transmitting terminal.

According to a method and apparatus for transmitting and receiving discovery signals for terminal-to-terminal communication according to the present invention, a discovery signal is generated by dividing it into first and second discovery signals, and a second discovery signal is determined through transmission resources of the first discovery signal. By doing so, the burden on the receiving end of the D2D terminal can be reduced.

1 is a view showing an overview of the D2D UE discovery method and an example of a signal flow according to an embodiment of the present invention,

2 is a diagram illustrating a specific operation process of a D2D transmitting terminal according to an embodiment of the present invention;

3 is a diagram illustrating a specific operation process of a D2D receiving terminal according to an embodiment of the present invention;

4 is a diagram showing a first embodiment of a discovery signal generating method according to an embodiment of the present invention;

5 is a diagram illustrating a second embodiment of a discovery signal generating method according to an embodiment of the present invention;

6 is a view showing a third embodiment of a discovery signal generation method according to an embodiment of the present invention;

7 illustrates an example of a physical layer channel structure of a first discovery signal according to an embodiment of the present invention;

8 illustrates another example of a physical layer channel structure of a first discovery signal according to an embodiment of the present invention;

9 illustrates a first embodiment of allocation resource mapping between first and second discovery signals in an embodiment of the present invention;

FIG. 10 illustrates a second embodiment of allocation resource mapping between first and second discovery signals in the present invention; FIG.

FIG. 11 illustrates a third embodiment of allocation resource mapping between first and second discovery signals in the present invention; FIG.

12 is a view showing a fourth embodiment of allocation resource mapping between first and second discovery signals in the present invention;

FIG. 13 illustrates a fifth embodiment of allocation resource mapping between first and second discovery signals in the present invention; FIG.

FIG. 14 illustrates a sixth embodiment of allocation resource mapping between first and second discovery signals in the present invention; FIG.

FIG. 15 illustrates a seventh embodiment of allocation resource mapping between first and second discovery signals in the present invention; and

16 is a diagram illustrating a configuration of a transmitter and a receiver of a D2D terminal according to an embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings. In the following description of the present invention, detailed descriptions of related well-known functions or configurations will be omitted if it is determined that the detailed description of the present invention may unnecessarily obscure the subject matter of the present invention. In addition, terms to be described below are terms defined in consideration of functions in the present invention, which may vary according to intention or custom of a user or an operator. Therefore, the definition should be made based on the contents throughout the specification.

Further, in describing the embodiments of the present invention in detail, an OFDM-based wireless communication system, in particular the 3GPP EUTRA standard will be the main target, but the main subject of the present invention is another communication system having a similar technical background and channel form. In addition, it is possible to apply with a slight modification in the range without departing greatly from the scope of the present invention, which will be possible in the judgment of those skilled in the art.

Hereinafter, a discovery signal resource allocation, a discovery signal detection method and apparatus including a discovery signal design method according to an exemplary embodiment of the present invention will be described in detail.

1 is a diagram illustrating an outline of a D2D UE discovery method and an example of a signal flow according to an embodiment of the present invention. 1 illustrates a discovery signal transmission and reception process between a discovery signal transmission D2D terminal (or D2D transmission terminal) and a discovery signal reception D2D terminal (or D2D reception terminal).

Referring to FIG. 1, the D2D support network upper layer 100 transmits a discovery signal transmission D2D terminal upper layer 101 to the discovery signal transmission D2D service related information list 102 for the discovery signal transmission D2D terminal and the discovery signal reception D2D terminal higher. In step 104, the discovery signal reception D2D service related information list for the D2D user equipment is transmitted to the layer 103. Here, the D2D support network upper layer 100 may correspond to various network entities such as a base station (eNB) and a mobility management entity (MME).

In addition, the D2D service-related information list includes all D2D service-related information necessary to provide the D2D service, and the D2D service-related information includes at least one of D2D ID, Application ID, Application-specific user ID, and Interest ID as described above. Include. The D2D service related information list may be prepared in advance by the D2D service provider.

The discovery signal transmission D2D terminal upper layer 101 transmits 106 a D2D service related information list received from the D2D support network upper layer 100 to the discovery signal transmission D2D terminal physical layer 105. Subsequently, the discovery signal transmission D2D terminal physical layer 105 generates a first discovery signal and a second discovery signal including information related to the D2D service to be transmitted (107).

Here, the first discovery signal may include a part of the D2D service-related information that the discovery signal transmission D2D terminal wants to notify neighboring D2D terminals, and the second discovery signal may include the remaining part or all of the D2D service-related information. have.

The discovery signal transmission D2D terminal physical layer 105 transmits (108) the generated first and second discovery signals to the discovery signal receiving D2D terminal. Herein, the discovery signal transmittable resource region may be predetermined or set by the base station. In addition, resources used by each D2D user equipment in the discovery signal transmittable resource region may be allocated from the base station. If there is no base station, each discovery signal D2D user equipment transmits its own discovery signal in a contention based manner. Resource can be determined. However, in the latter case, the D2D UEs accept the possibility of collision between discovery signals.

Meanwhile, as described above, the discovery signal receiving D2D terminal upper layer 103 transmits the list received from the D2D support network upper layer 100 to the discovery signal receiving D2D terminal physical layer 109 (110). Thereafter, the discovery signal receiving D2D terminal physical layer 109 detects a resource area other than the discovery signal resource allocated by the D2D terminal physical layer 109 according to an embodiment of the present invention (hereinafter, 'Two step'). Discovery process ”).

The two step discovery process is as follows. First, the discovery signal receiving D2D terminal receives the first discovery signal from the discovery signal transmitting D2D terminal, detects a part of the above-described D2D service related information, and compares the information with its own D2D service related information list.

If the discovery signal is received information matching the interest or need of the D2D terminal itself is attempted to detect the information of the second discovery signal associated with the first discovery signal including the information. If there is no abnormality after comparing the D2D service related information detected from the second discovery signal with the own D2D service related information list and checking the error, the discovery signal receiving D2D terminal detects the discovery signal receiving D2D terminal upper layer 103. Service-related information is delivered (112).

2 is a diagram illustrating a specific operation process of a D2D transmitting terminal according to an embodiment of the present invention. FIG. 2 specifically illustrates the operation of the D2D transmitting terminal according to steps 106 to 108 of FIG. 1.

Referring to FIG. 2, in step 210, the D2D transmitting terminal obtains a D2D service related information list from an upper layer. Thereafter, in step 220, the transmitting terminal generates first and second discovery signals to be transmitted based on the D2D service related information list obtained in step 210.

The embodiment of FIG. 4 to FIG. 6 to be described later may be applied to the specific discovery signal generation method of step 220. The embodiment of FIGS. 7 and 8 may be described in the form of a physical channel for transmitting the first and second discovery signals. Can be applied.

In operation 230, the first discovery signal resource is determined. The first discovery signal resource may be determined by the base station or the D2D transmitting terminal. The second discovery signal resource determined in operation 240 is determined based on the first discovery signal resource determined in operation 230. In the discovery signal resource determination process of

steps

230 and 240, one of the embodiments of FIGS. 9 to 15 may be applied or an explicit resource allocation method may be applied as described above.

Finally, the D2D transmitting terminal transmits the first and second discovery signals through the resources determined as described above in step 250 and terminates the discovery signal transmission operation according to the embodiment of the present invention.

3 is a diagram illustrating a specific operation process of the D2D receiving terminal according to an embodiment of the present invention. 3 illustrates in detail the operation of the D2D receiving terminal according to steps 110 to 112 of FIG. 1.

Referring to FIG. 3, the D2D receiving terminal acquires a D2D service related information list from an upper layer in step 310. In operation 320, the first discovery signal information is detected for all possible first discovery signal resources.

In step 330, the first discovery signal information detected in step 320 is compared with the D2D service related information list acquired in step 310, and the detected first discovery signal information corresponds to a D2D service whose interest matches one of the D2D service related information list. It checks whether a part of related information, for example, 16 bits of LSB (Least Significant Bit) of all bits of D2D service related information is matched.

If the first discovery signal information corresponding to the interest of the D2D receiving terminal exists in step 340, the D2D receiving terminal proceeds to step 350 and recognizes the corresponding second discovery signal resource from the first discovery signal resource. In operation 360, the second discovery signal information is detected with respect to the recognized second discovery signal resource. In operation 350, one of the embodiments of FIGS. 9 to 15 may be applied, or an explicit resource allocation method may be applied as described above.

If there is no first discovery signal information corresponding to the D2D service related information list in step 340, the process proceeds to step 320 and attempts to detect the first discovery signal again.

In step 370, the D2D receiving terminal compares the discovery signal information finally acquired by the D2D receiving terminal with the D2D service related information list to check whether there is a match, and performs an error check using a CRC. do. The final discovery signal information acquisition and error check may be performed under the assumption of the discovery signal generation method of the embodiment shown in FIGS. 4 to 6.

In step 380, if the discovery signal information corresponding to the interest of the D2D terminal itself and there is no error exists, the D2D receiving terminal proceeds to step 390 and transmits the corresponding information to a higher level such as an application level. Accordingly, the D2D receiving terminal performs a D2D service related operation with respect to the D2D transmitting terminal.

If the interest does not match or an error is detected, the process proceeds to step 320 and attempts to detect the first discovery attempt again.

After performing the steps described above, the D2D receiving terminal terminates the discovery signal receiving operation according to the embodiment of the present invention.

4 is a diagram illustrating a first embodiment of a discovery signal generation method according to an embodiment of the present invention. FIG. 4 is a view to explain specific examples of the first and second discovery signal generation process 107 of FIG. 1 and step 220 of FIG. 2.

Referring to FIG. 4, assuming that the size of the D2D service-related information that the D2D UE wants to notify is 100 bits in total, LSB 16 bits of the 100 bits information may be used for generating the first discovery signal (400). Can be. In this case, 16 bits of information included in the first discovery signal may be obtained by performing a modulo operation on 100 bits of all D2D service related information. In addition, a CRC may be added to enable an error check when detecting the first discovery signal. If the structure of the first discovery signal is difficult to include both 16-bit information and the CRC, CRC addition may be omitted.

Next, 84 bits other than the 16 bits used for generating the first discovery signal among all 100 bits of information are used for generating the second discovery signal (401). Here, a CRC is added to enable an error check when detecting the second discovery signal. The specific number of information bits of the D2D service related information used for generating the first and second discovery signals described above is not limited to this embodiment.

5 is a diagram illustrating a second embodiment of a discovery signal generation method according to an embodiment of the present invention. FIG. 4 illustrates another specific example of the first and second discovery signal generation process 107 of FIG. 1 and the operation 220 of FIG. 2.

Referring to FIG. 5, when generating the first discovery signal under the assumption of the same number of bits as in FIG. 4 described above, some 16-bit information is used 500 of the 100-bit information as in the first embodiment, and the second When generating the discovery signal, 100 bits of all D2D service related information including 16 bits used for generating the first discovery signal are used (501). This is to ensure the detection performance of the receiving end by performing an error check and comparison with the D2D service related information list for all 100 bits in the second discovery signal detection after the first discovery signal detection.

6 is a diagram illustrating a third embodiment of a discovery signal generation method according to an embodiment of the present invention. FIG. 4 is a view to explain another specific example of the first and second discovery signal generation process 107 of FIG. 1 and step 220 of FIG. 2.

Referring to FIG. 6, when generating the first discovery signal under the assumption of the same number of bits as in FIG. 4 described above, some 16-bit information is used 600 among all 100-bit information in the same manner as in the first embodiment. When generating the discovery signal, 84 bits other than the 16 bits used for generating the first discovery signal are used (601).

In addition, assuming that the length of the CRC used to generate the second discovery signal is 16 bits, the 16 bits included in the first discovery signal are masked 602 to the CRC. This avoids an increase in the number of information bits included in the second discovery signal and maintains 84 bits, while also including 16 bits of information about the first discovery signal through the CRC masking in the second discovery signal and performing an error check with the CRC. This is to ensure the detection performance of the receiving end.

7 is a diagram illustrating an example of a physical layer channel structure of a first discovery signal according to an embodiment of the present invention. As described with reference to FIG. 3, when considering a two step discovery process for reducing a terminal receiver burden according to an embodiment of the present invention, the first discovery signal includes less information bits than the second discovery signal rather than the maximum number of information bits. While the first discovery signal transmitted from a plurality of D2D UEs can be efficiently multiplexed structure is advantageous.

Therefore, in the present embodiment, it may be assumed that the first discovery signal has a structure similar to that of the control channel of the 3GPP LTE standard. In particular, in consideration of the signal transmitted by the D2D user equipment, a physical uplink control channel (PUCCH) format 3 form that may include the most information bits of the uplink control channel of LTE will be described as an example.

Referring to FIG. 7, the PUCCH format 3 structure includes a subframe having a length of 1 ms, two slots having a length of 0.5 ms constituting the subframe, and 12 subcarriers with frequency. It uses the RB (Resource Block) resource unit. Here, one slot includes five single carrier frequency division multiple access (SC-FDMA) symbols including data and two single carrier frequency division multiple access (SC-FDMA) including a reference signal (RS), which is a reference signal. It consists of symbols.

In this embodiment, it may be assumed that the discovery signal is not transmitted in the last one SC-FDMA symbol of the last slot in which the discovery signal is transmitted. This means that when the discovery signal transceivable subframes are present in succession, the discovery signal transmission and reception subframes can receive discovery signals from other D2D UEs in the remaining subframes except for a specific subframe in which each D2D UE transmits its discovery signal. Detection should be attempted, in which case one symbol is used as a time interval for transmission of a discovery signal and reception switching.

PUCCH format 3 uses a QPSK modulation scheme and can transmit a maximum of 22 information bits (48 encoded bits) per channel, and the information bits are first encoded in step 700. Here, assuming that up to 22 bits of information are D2D service-related information bits included in the first discovery signal, the information bits are divided into two and subjected to (32, O) Reed Muller (RM) coding. Thereafter, the two RM encoded bits are subjected to a rate matching process to match the number of 48 encoded bits. Thereafter, 24 QPSK symbol strings are generated through scrambling (step 701) and QPSK modulation (step 702). In the present embodiment, this is d (0), d (1),... , d (22), d (23).

The first 12 symbols of the QPSK symbols are included in the first slot and the remaining 12 symbols are included in the second slot. Twelve symbols per slot are multiplied by an orthogonal cover code in SC-FDMA data symbols (703). In FIG. 7, W0, W1, W2, W3, and W4 mean each element of a length 5 orthogonal cover code used for the first slot, and W'0, W'1, W'2, and W'3 are second slots. Each element of length 4 orthogonal cover code used for.

As described above, in the present embodiment, it is assumed that the last one SC-FDMA symbol of the last slot is not used. Thus, an orthogonal cover code having a length of 4 is applied to the second slot. The first discovery signals transmitted from another D2D terminal may be multiplexed onto the same RB in one subframe.

The 12 symbols multiplied by the orthogonal cover code in each SC-FDMA data symbol are cyclic shifted in frequency (704) and entered into a Discrete Fourier Transform (DFT) input stage of length 12 (704). The DFT output is then mapped to the frequency domain location of the Inverse Fast Fourier Transform (IFFT) input stage (706), and the SC-FDMA signal is generated through the IFFT process.

8 is a diagram illustrating another example of a physical layer channel structure of a first discovery signal according to an embodiment of the present invention. As described with reference to FIG. 3, when considering a two step discovery process for reducing the burden on the terminal receiver according to an exemplary embodiment of the present invention, the second discovery signal is greatly influenced according to the first discovery signal detection result. Thus, it is advantageous for the first discovery signal to have a structure that can include a sufficient number of encoded bits to apply relatively strong channel coding instead of including relatively few information bits as compared to the second discovery signal.

Accordingly, in the present embodiment, it may be assumed that the first discovery signal has a structure similar to a data channel of the 3GPP LTE standard. In particular, in consideration of the signal transmitted by the D2D UE will be described taking the form of PUSCH (Physical Uplink Shared Channel) which is an uplink data channel of LTE as an example.

Referring to FIG. 8, the PUSCH structure uses a subframe having a length of 1 ms, two slots having a length of 0.5 ms constituting the subframe, and an RB resource unit occupying 12 subcarriers in frequency. Here, one slot is composed of six SC-FDMA symbols including data and one SC-FDMA symbol including RS as a reference signal. In the present embodiment, it may be assumed that the last one SC-FDMA symbol of the last slot does not transmit a signal, as described above with reference to FIG. 7.

PUSCH may use various modulation schemes, but in this embodiment, it is assumed that the QPSK modulation scheme is used in consideration of performance when detecting a discovery signal. Under this assumption, the PUSCH can transmit 11 SC-FDMA data symbols X 12 subcarrier X modulation bits = 2 < 264 > encoded bits in one subframe and RB resource.

The information bits are first encoded in step 800. Here, the amount of information bits is variable depending on the channel coding rate. If one-half channel coding is assumed, 132 information bits can be transmitted, and if the stronger 1 / 4-channel coding is assumed, 66 information bits can be transmitted. The channel coded bits are then subjected to scrambling (step 801) and QPSK modulation (step 802) to generate a symbol sequence. The generated symbols enter the DFT input terminal of length 12 of each SC-FDMA data symbol in order. The DFT output is then mapped to the frequency domain location of the IFFT input stage and the SC-FDMA signal is generated through the IFFT process.

FIG. 9 is a diagram illustrating a first embodiment of allocation resource mapping between first and second discovery signals in an embodiment of the present invention.

Referring to FIG. 9, it may be assumed that resources allocated to the first discovery signal and resources allocated to the second discovery signal are first divided in time. In addition, it may be assumed that the first and second discovery signals of each D2D UE are allocated in units of an upper limit RB and an upper limit subframe in time.

Here, the first discovery signals of the respective D2D UEs are allocated to resources in the first discovery

signal subframe group

900 and 907 composed of a preset number of subframes on a preset time position. The first discovery

signal subframe group

900 and 907 may appear with a predetermined period 901 on the time axis. There is also a second discovery

signal subframe group

903, 908 after a predetermined time interval 902 from the first discovery

signal subframe group

900, 907. Second discovery signals of respective D2D UEs are allocated to resources of the second discovery

signal subframe group

903 and 908.

Hereinafter, the blocks of the

respective rows

904, 905, and 906 are the first discovery signal resources transmitted from six D2D terminals A, B, C, D, E, and F in subframe units, assuming 6 RB channel bandwidths. And different examples in which a second discovery signal resource corresponding to the first discovery signal resource is mapped.

In this case, the second discovery signal subframe group of the subframe to which the second discovery signals are allocated and the temporal position in the first discovery signal subframe group 900 of the subframe to which the first discovery signals of the A to F D2D terminals are allocated ( 903) The position in time may be preset to be the same or have a difference by a specific number of subframes.

In addition, in the first discovery signal subframe group 907 and the second discovery signal subframe group 908 appearing in the next period, the previous first discovery signal subframe group 900 and the second discovery signal sub of the A to F D2D UEs. Positions in time and frequency relative to frame group 903 may be cyclic shifted. In this case, the time and frequency shift values for each of the first and second discovery signal resources may be the same or different. Alternatively, the time and frequency resources may be changed in a predetermined pattern every time the first and second discovery signal subframe groups appear. May be hopping. Alternatively, a setting for enabling or disabling the above-described time and frequency resource change may be signaled to each D2D terminal from the base station. This time and frequency resource change is to prevent certain D2D UEs in the system from allocating discovery signal resources to a channel of low quality.

Looking at a particular subframe in the first discovery signal subframe group 900 in row 904, the first discovery signals of each of the six D2D UEs are allocated in order from the top RB to the bottom RB. Subsequently, the second discovery signal of the corresponding D2D UEs is mapped to the same RB as the first discovery signal in a specific subframe in the second discovery signal subframe group 903.

Next, in the case of 905, when a specific subframe in the first discovery signal subframe group 900 is viewed, the first discovery signals of each of six D2D UEs are allocated in order from the top RB to the bottom RB. Subsequently, the second discovery signals of the corresponding D2D UEs are mapped to have an offset of 2 RBs with the first discovery signal in a specific subframe in the second discovery signal subframe group 903. Also, in the embodiment of 905, the frequency positions of the first and second discovery

signal subframe groups

907 and 908 of the next period are shifted by 3 RB from the previous period.

In the case of row 906, when a specific subframe in the first discovery signal subframe group 900 is viewed, the first discovery signals of each of the six D2D UEs are allocated in order from the top RB to the bottom RB in the first slot. Thereafter, in the second slot, the first discovery signal resource of each of six D2D UEs is shifted by 3 RB with respect to the first slot. This slot-based hopping method is for improving the performance of the first discovery signal detection through frequency diversity, and can be equally applicable to the second discovery signal. Subsequently, the second discovery signals of the corresponding D2D UEs are mapped to the same RB as the first discovery signal in a specific subframe in the second discovery signal subframe group 903.

FIG. 10 illustrates a second embodiment of allocation resource mapping between first and second discovery signals in the present invention.

Referring to FIG. 10, it may be assumed that first, a resource to which a first discovery signal is allocated and a resource to which a second discovery signal is allocated are divided in frequency within the same subframe. Here, the discovery

signal subframe groups

1000 and 1002 have a preset period 1001. For example, in the present embodiment, the discovery signal subframe group 1002 appears in the next period of the discovery signal subframe group 1000.

Hereinafter, blocks of each of

rows

1003, 1004, and 1005 are each of the first discovery signal resources A-1, transmitted from three D2D terminals A, B, and C in subframe units, assuming 6 RB channel bandwidths. Different examples in which the second discovery signal resources A-2, B-2, and C-2 are mapped from B-1 and C-1 and the first discovery signal resource are shown.

At this time, the position in time in the discovery signal subframe group 1000 of the subframe to which the discovery signals of A to C D2D UEs are allocated and the position in time in the discovery signal subframe group 1002 appearing in the next period are the same or specified subframes. It may be preset to have a difference by the number of frames. In addition, in the discovery signal subframe group 1002 appearing in the next period, a position in time and frequency compared to the previous discovery signal subframe group 1000 of A to C D2D UEs may have a constant value and may be cyclically shifted. Alternatively, time and frequency resources may be hopping in a predetermined pattern every time a discovery signal subframe group appears. In addition, the configuration for enabling or disabling the above-described time and frequency resource changes may be signaled to each D2D terminal from the base station. This time and frequency resource change is to prevent certain D2D UEs in the system from allocating discovery signal resources to a channel of low quality.

In the case of row 1003, the first and second discovery signals of each of the three D2D UEs are alternately located in the adjacent RBs in a specific subframe in the discovery signal subframe group 1000, and the RB to RB in order from A to C UEs are alternately located. Can be allocated. This is to allow the first and second discovery signals to be received under similar channel conditions. If the second discovery signal is received through a low quality channel, the overall discovery signal detection performance will be degraded even if the first discovery signal is received through an excellent channel. Therefore, two discovery signals may be allocated to adjacent RBs to ensure performance for at least a case where the first discovery signal is well detected.

Line 1004 shows an example of another possible mapping. After the first discovery signal of the A-C terminal is located in the adjacent RB and is allocated in order from the highest RB in the order of the A-C terminal, the second discovery signal of the A-C terminal is located in the adjacent RB while the A-C terminal It is allocated in order from the top RB in order.

In the case of row 1005, discovery signal resources of three D2D UEs allocated in the same slot as the 1003 row in the first slot in a specific subframe in the discovery signal subframe group 1000 are shifted by 3 RB in the second slot. This slot-by-slot hopping method is for improving the performance of discovery signal detection through frequency diversity.

FIG. 11 is a diagram illustrating a third embodiment of allocation resource mapping between first and second discovery signals in the present invention.

Referring to FIG. 11, it may be assumed that resources allocated to the first discovery signal and resources allocated to the second discovery signal are first divided in time. In addition, it may be assumed that the first and second discovery signals of each D2D UE are allocated in units of an upper limit RB and an upper limit subframe in time.

Here, the first discovery signals of the respective D2D UEs are allocated to resources in the first discovery signal subframe group 1100 composed of a preset number of subframes on a preset time position. The first discovery signal subframe group 1100 exists with a preset period 1101. In addition, a plurality of second discovery

signal subframe groups

1103 and 1104 exist after a predetermined time interval 1102 from the first discovery signal subframe group 1000.

Here, a plurality of second discovery signal subframe groups may exist within the discovery period 1101. For example, within a period 1101, a plurality of second discovery

signal subframe groups

1103, 1104 may exist with a predetermined time interval 1105. The value of this time interval 1105 may be the same as or different from the time interval of 1102. Second discovery signals of respective D2D UEs may be allocated to resources in the plurality of second discovery

signal subframe groups

1103 and 1104.

As the basic time and frequency resource mapping method and the hopping or constant offset application method of the present embodiment, the same method as described in FIG. 9 may be applied. However, the difference between the embodiment shown in FIG. 9 and the present embodiment is that the wireless communication resource region to which the first discovery signal can be allocated is divided into a plurality of sub-regions as many as possible discovery signal types, and the first discovery signal is It is possible to know the size of the resource unit to which the second discovery signal is allocated according to which subregion is allocated to the radio communication resource.

That is, the type of the discovery signal can be known through the radio communication resource region to which the first discovery signal is allocated. The type of the discovery signal is determined according to the size of the D2D service related information included in the discovery signal, and the number of possible discovery signal types may be limited to a preset value. For example, the type of discovery signal may vary according to the type of D2D service or the type of content to be transmitted. If the discovery signal type is different, the size of discovery signal information may vary.

For example, as shown in FIG. 11, a first discovery signal of UEs having a second discovery signal in units of 1 RB is allocated within the uppermost 2 RB region of the channel bandwidth 6 RBs in the first discovery signal subframe group 1100. Can be. In the case of Figure 11, this corresponds to the discovery signals of the terminals A, B. In addition, the first discovery signal of the UEs having the second discovery signal in units of 2 RBs may be allocated in the middle 2 RB region of the channel bandwidth 6 RBs in the first discovery signal subframe group 1100. This corresponds to discovery signals of terminals C and D. Lastly, the first discovery signal of the UEs having the second discovery signal in units of 3RBs may be allocated in the lower 2 RB region of the channel bandwidth 6 RBs in the first discovery signal subframe group 1100. This corresponds to discovery signals of terminals E and F.

In this case, when only one second discovery signal subframe group is used, all of the second discovery signals of A to F terminals cannot be accommodated, and as shown in FIG. 11, a plurality of second discovery signal subframe groups may be utilized.

For example, when two second discovery

signal subframe groups

1103 and 1104 are utilized, as shown in FIG. 11, the second discovery signal subframe group 1103 includes a first RB unit of terminals A and B. 2 discovery signals and a second discovery signal in units of 2 RBs of terminals C and D are sequentially assigned to six RBs, and the second discovery signal subframe group 1104 includes a second discovery signal in units of 3 RBs of terminals E and F. It is allocated sequentially to six RBs.

Alternatively, the second discovery signal of the A to F terminals may be accommodated by increasing the length of the subframe group, that is, the number of subframes included, instead of using one second discovery signal subframe group.

12 illustrates a fourth embodiment of allocation resource mapping between the first and second discovery signals in the present invention.

Referring to FIG. 12, it may be assumed that a resource to which the first discovery signal is allocated and a resource to which the second discovery signal is allocated are divided in frequency within the same subframe. The discovery signal subframe group 1200 has a preset period 1201. In this embodiment, the discovery signal subframe group 1200 is shown up to the discovery signal subframe group 1202 appearing in the next period.

In addition, assuming the 12 RB channel bandwidth, the first discovery signal resources A-1, B-1, C-1, D transmitted from four D2D terminals A, B, C, and D in subframe units, respectively. -1) and an example in which the second discovery signal resources A-2, B-2, C-2, and D-2 are mapped are shown.

The examples shown in FIG. 10 may be applied to the basic time and frequency resource mapping method and the hopping or constant offset application method of the embodiment of FIG. 12. However, the difference between the embodiment shown in FIG. 10 and the present embodiment is that the wireless communication resource region to which the first discovery signal can be allocated is divided into as many subregions as the number of possible discovery signal types, and the first discovery signal. Can be known together with the size of the resource unit to which the second discovery signal is allocated according to which sub-area has been allocated to the wireless communication resource.

That is, the type of the discovery signal can be known through the radio communication resource region to which the first discovery signal is allocated. The type of the discovery signal is determined according to the size of the D2D service related information included in the discovery signal, and the number of possible discovery signal types may be limited to a preset value.

For example, the first discovery signal and the second discovery signal of terminals transmitting the second discovery signal in units of 1 RB may be allocated to the highest 4 RB region of the channel bandwidth 12 RBs. This corresponds to the first discovery signals A-1 and B-1 of the terminals A and B and the second discovery signals A-2 and B-2. In addition, the first discovery signal and the second discovery signal of the terminals having a discovery signal of 2RB unit may be allocated to the 3 RB region after the above-described 4RB of the channel bandwidth of 12 RB. This corresponds to the first discovery signal C-1 and the second discovery signal C-2 of the terminal C. FIG. Lastly, the first discovery signal and the second discovery signal of the UEs having the second discovery signal in units of 4RBs may be allocated within the lowest 5 RB region of the channel bandwidth 12 RBs. This corresponds to the first discovery signal D-1 and the second discovery signal D-2 of the terminal D. FIG.

In this case, if the size of the frequency domain to which the discovery signal can be allocated is too small, the discovery signals of the A to D terminals cannot be accommodated in one discovery signal subframe group, and thus, a plurality of second discovery signal subframe groups may be utilized. have. Alternatively, the size of the frequency domain to which the discovery signal can be allocated may be increased to accommodate all of the discovery signals of the A to D terminals using one subframe group.

FIG. 13 illustrates a fifth embodiment of allocation resource mapping between first and second discovery signals in the present invention.

Referring to FIG. 13, it may be assumed that the first discovery signal 1300 has a control channel structure such as PUCCH format 3 as described with reference to FIG. 7. In addition, it may be assumed that the second discovery signal 1301 has a data channel structure such as a PUSCH as described with reference to FIG. 8. In addition, it may be assumed that frequency resources for the first and second discovery signals are divided like frequency resources for the PUCCH and the PUSCH, respectively, in the same subframe. At this time, the subject that determines the discovery signal resource allocation of each D2D terminal may be a base station or a D2D terminal that transmits the first discovery signal.

The second discovery signal of the PUSCH structure is allocated in a Virtual RB (VRB) unit in a PUSCH region when resource allocation. In the present embodiment, the VRB index is denoted as “PUSCH VRB”. On the other hand, the first discovery signal of the PUCCH format 3 structure is determined by the parameter “N_1 ^st _discovery” transmitted to each D2D UE UE-specifically through RRC (Radio Resource Control) signaling during resource allocation. Here, the RB index, the orthogonal cover code index, and the cyclic shift value to which the first discovery signal is transmitted are all determined as a function of N_1 ^st _discovery. In addition, the PUCCH resource region to which the first discovery signals are allocated may be hopping in units of slots for frequency diversity acquisition as shown in the present embodiment.

As described in FIG. 7, when the first discovery signal has a PUCCH format 3 structure, when the last SC-FDMA symbol in a subframe is used as a discovery signal transmission and reception switching interval, up to four UEs in one RB through an orthogonal cover The first discovery signal from may be multiplexed. Here, N_1 ^st _discovery for the first discovery signals from the four terminals are referred to as N_1 ^st _discovery 0, N_1 ^st _discovery 1, N_1 ^st _discovery 2, and N_1 ^st _discovery 3, respectively.

In the embodiment of FIG. 13, the N_1 ^st _discovery 0 to 3 correspond to PUSCH VRB 0 to 3 one to one, respectively. Therefore, the discovery signal receiving D2D UEs can identify the resource to which the second discovery signal is allocated from the resource to which the first discovery signal is allocated without additional signaling.

FIG. 14 illustrates a sixth embodiment of allocation resource mapping between first and second discovery signals in the present invention.

Referring to FIG. 14, the assumptions about the structure of the first discovery signal 1400 and the second discovery signal 1401 and resource allocation parameters are the same as in FIG. 13. In addition, it is assumed that frequency resources for the first and second discovery signals are divided as frequency resources for the PUCCH and the PUSCH, respectively, in the same subframe. At this time, the subject that determines the discovery signal resource allocation of each D2D terminal may be a base station or a D2D terminal transmitting the first discovery signal.

In contrast to FIG. 13, the difference of the embodiment of FIG. 14 is that it can accommodate the first and second discovery signals transmitted from the doubled number of terminals in the same frequency domain.

For example, if N_1 ^st _discovery for the first discovery signal transmitted from eight D2D UEs is N_1 ^st _discovery 0 to 7, respectively, N_1 ^st _discovery 0 to 3 correspond to PUSCH VRB 0 to 3 in one-to-one order, respectively. do. N_1 ^st _discovery 4 to 7 also correspond one-to-one with PUSCH VRB 0 to 3, respectively. Therefore, a second discovery signal from multiple terminals can be allocated in one same second discovery signal allocation resource unit. The method has an advantage that it can accommodate more discovery signals of more D2D UE in one discovery signal subframe. On the other hand, there is a possibility that the receiving end detection performance deterioration due to interference occurs according to the channel state of each link between the D2D terminals and the receiving D2D terminals of the second discovery signals allocated to the same resource.

FIG. 15 illustrates a seventh embodiment of allocation resource mapping between first and second discovery signals in the present invention.

Referring to FIG. 15, the assumptions about the structure of the first discovery signal 1500 and the second discovery signal 1501 and resource allocation parameters are the same as those of FIGS. 13 and 14. In addition, it is assumed that frequency resources for the first and second discovery signals are divided as frequency resources for the PUCCH and the PUSCH, respectively, in the same subframe. At this time, the subject that determines the discovery signal resource allocation of each D2D terminal may be a base station or a D2D terminal transmitting the first discovery signal.

In contrast to the embodiments of FIGS. 13 and 14, the differentiation point of the embodiment of FIG. 15 is that the resource allocation unit size of the associated second discovery signal is determined according to the resource region to which the first discovery signal is allocated, that is, the range of N_1 ^st _discovery value. I can see.

For example, N_1 ^st _discovery for the first discovery signals transmitted from three D2D UEs are referred to as N_1 ^st _discovery 0 to 2, respectively. Wherein the second detected signal associated with the first detected signal having a value within N_1 _discovery N_1 ^st ^st _discovery 0 ~ 1 range are assigned to resources of 1RB size. On the other hand N_1 ^st _discovery first detected signal and the second detected signal associated with a large N_1 ^st _discovery value than the value of the 0-1 range are assigned to resources of 2RB size.

As in the above-described embodiment, the wireless communication resource parameter value range that can be allocated to the first discovery signal is divided into a plurality of range areas as many as the number of possible discovery signal types, and the first discovery signal is in wireless communication within a certain range area. The size of the resource unit to which the second discovery signal is allocated may be known according to whether the resource parameter value is allocated. That is, the type of the discovery signal can be known through the range of the radio communication resource parameter value to which the first discovery signal is assigned. The type of the discovery signal is determined according to the amount of D2D service information included in the discovery signal, and the number of possible discovery signal types is limited to a preset value.

As described above, a method in which the second discovery signal resource is implicitly mapped from the first discovery signal resource may be variously applied to cases in which the first discovery signal has a control channel or data channel structure. Meanwhile, an explicit mapping method including the second discovery signal resource allocation information in the information of the first discovery signal may also be applied. Such resource allocation information may include frequency allocation information of the second discovery signal and information on which subframe of the discovery signal subframe group is allocated.

16 is a diagram illustrating a configuration of a transmitter and a receiver of a D2D terminal according to an embodiment of the present invention. In this case, it is assumed that transmission and reception use an OFDM-based signal.

Referring to FIG. 16, a discovery signal transmission D2D terminal may include a transmission controller 1600, a discovery signal generator 1601, and an OFDM-based transmitter 1602.

The transmission controller 1600 has information about D2D service related information to be transmitted by the corresponding D2D terminal, a method of generating first and second discovery signals, a resource mapping method between the first discovery signal and the second discovery signal, and the like. The first discovery signal generation using part of the D2D service related information of the discovery signal generator 1601 and the second discovery signal generation process using the remaining or all of the D2D service related information are controlled.

The first and second discovery signals output from the discovery signal generator 1601 are allocated to the discovery signal transmission resource for each D2D terminal in the form of a physical channel having a control channel or a data channel structure in the OFDM based transmitter 1602. Herein, the transmission controller 1600 controls the time and frequency resource allocation process for each of the first and second discovery signals in the OFDM-based transmitter 1602.

Meanwhile, the discovery signal receiving D2D terminal includes an OFDM based receiving unit 1603, a receiving control unit 1604, and a discovery signal detecting unit 1605. Here, the OFDM-based receiving unit 1603 distinguishes the first and second discovery signal resources in the physical channel form having a control channel or data channel structure in all resource regions capable of transmitting the discovery signal of the received signal, and extracts discovery signals. . The above process is controlled by the reception control unit 1604 having information on possible time and frequency resources to which the first and second discovery signals can be allocated. The first and second synchronization signals extracted by the above-described OFDM based receiver 1603 are input to the discovery signal detector 1605, where the D2D service related information is detected. This process is also controlled by the reception controller 1604 having the D2D service related information.

According to the embodiment of the present invention described above, the discovery signal is generated by dividing the first and second discovery signals, wherein the first discovery signal includes a part of the D2D service-related information, and the second discovery signal is the D2D service-related information. By designing to include the remaining part or all of the D2D service information, there is an advantage of reducing the burden on the receiving end of the D2D terminal.

For example, assume that one D2D UE should attempt to detect discovery signals from 100 neighboring D2D UEs at the time of discovery discovery, and that one discovery signal includes 100 bits of D2D service related information. In order to detect these at once, the D2D UE should attempt to detect as many as 100 bits X 100 discovery signals. However, by configuring the first and second discovery signals as in the present invention, the two step discovery method can be supported.

That is, if it is assumed that the first discovery signal includes only 30 bits, which is a part of the entire 100-bit D2D service information, and the remaining 70 bits are included in the second discovery signal, the D2D user equipment first has a size of 30 bits X 100 first discovery signals. Attempt to detect Then, if 10 first discovery signals corresponding to the interest of the corresponding D2D UE are found, additionally, only an attempt to detect the size of the 70-bit X 10 second discovery signals is needed. Therefore, compared to the 100-bit X 100 detection attempts, it is possible to confirm the effect of reducing the burden on the receiving end of the D2D terminal. This is summarized in Table 1 below.

Table 1

	D2D terminal receiving burden
	First discovery signal	Second discovery signal
Single detection	100 bits X 100 discovery signals	-
Two step	30 bits X 100 discovery signals	70 bits X 10 discovery signals

In addition, the present invention has the advantage that does not require additional signaling to inform the discovery signal type by designing to inform the type of the corresponding discovery signal through the radio communication resource region to which the first discovery signal is allocated. If the interest of the D2D UE is limited to a specific service type, an attempt is made to detect the first discovery signal only within the first discovery signal radio communication resource region corresponding to the service type, and interest is more specific within the result. The first discovery signals matching may be found and attempt to detect a second discovery signal associated with them. From this, it is also possible to obtain the advantage of reducing the burden on the receiving end of the D2D terminal.

Although the above-described embodiment has been described with respect to the case where the OFDM-based transmission scheme is applied, the present invention is not limited thereto and may be applied to other transmission schemes and other wireless communication resources, for example, code domain resources or spatial domain resources. . The same may be applied to the mapping relationship between the first discovery signal allocation resource and the second discovery signal allocation resource associated with it. That is, the present invention can be applied to various resources such as a code domain and a spatial domain without being limited to time and frequency resources.

Meanwhile, in the detailed description of the present invention, specific embodiments have been described, but various modifications may be made without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be determined not only by the scope of the following claims, but also by the equivalents of the claims.

Claims

A method for transmitting a discovery signal of a transmitting terminal for terminal to terminal communication,

Generating a first discovery signal and a second discovery signal to be transmitted to a receiving terminal based on the information related to the service provided through the terminal to terminal communication;

Allocating the first discovery signal and the second discovery signal to a second discovery signal transmission resource determined from a preset first discovery signal transmission resource and the first discovery signal transmission resource; And

And transmitting the first discovery signal and the second discovery signal to the receiving terminal.
The method of claim 1,

The first discovery signal includes a part of the service related information, and the second discovery signal includes all of the service related information except for the information included in the first discovery signal among the service related information. Discovery signal transmission method.
The method of claim 1,

The service related information is transmitted from a network entity supporting the terminal-to-terminal communication, an identifier of the transmitting terminal for performing the terminal-to-terminal communication, and an identifier of an application related to the terminal-to-terminal communication. And at least one of an identifier of the transmitting terminal related to the application and interest information of the transmitting terminal.
The method of claim 1,

The first discovery signal resource and the second discovery signal resource is a discovery signal transmission method, characterized in that the frequency or time position is changed based on at least one of a predetermined period, the subframe in which the discovery signal is transmitted and the slot.
The method of claim 1,

The magnitude of the second discovery signal resource is determined from the first discovery signal resource.
In the receiving signal receiving method of the receiving terminal for terminal to terminal communication,

Receiving a first discovery signal of a transmitting terminal generated based on information related to a service provided through the terminal-to-terminal communication through a first discovery signal transmission resource preset;

Comparing the first discovery signal information of the transmitting terminal detected from the first discovery signal with the service related information of the receiving terminal previously stored;

Determining a second discovery signal transmission resource from the first discovery signal transmission resource if the first discovery signal information of the transmitting terminal corresponds to service related information of the receiving terminal;

Receiving a second discovery signal of the transmitting terminal through the second discovery signal transmission resource;

Comparing second discovery signal information of the transmitting terminal and service related information of the receiving terminal detected from the second discovery signal; And

And performing the terminal-to-terminal communication operation with respect to the transmitting terminal, if the second discovery signal information of the transmitting terminal corresponds to the service related information of the receiving terminal.
The method of claim 6,

The first discovery signal includes a part of the service related information, and the second discovery signal includes all or the service related information except for the information included in the first discovery signal among the service related information. To find the signal receiving method.
The method of claim 6,

The service related information is transmitted from a network entity supporting the terminal-to-terminal communication, an identifier of the terminal for performing the terminal-to-terminal communication, an identifier of an application related to the terminal-to-terminal communication, And at least one of an identifier of the terminal associated with the application and the interest information of the terminal.
The method of claim 6,

The first discovery signal resource and the second discovery signal resource is a discovery signal receiving method, characterized in that the frequency or time position is changed based on at least one of a predetermined period, the subframe and the slot in which the discovery signal is transmitted.
The method of claim 6,

And in the determining of the second discovery signal transmission resource, further determining the size of the second discovery signal resource according to the first discovery signal resource.
An apparatus for transmitting a discovery signal of a transmitting terminal for terminal to terminal communication,

A discovery signal transmitter for transmitting the discovery signal to a receiving terminal; And

Generating a first discovery signal and a second discovery signal to be transmitted to the receiving terminal based on information related to a service provided through the terminal-to-terminal communication, and a preset first discovery signal transmission resource and the first discovery signal transmission resource And a control unit for allocating the first discovery signal and the second discovery signal to a second discovery signal transmission resource determined from the controller, and controlling to transmit the first discovery signal and the second discovery signal to the receiving terminal. Discovery signal transmission device, characterized in that.
The method of claim 11,

The first discovery signal includes a part of the service related information, and the second discovery signal includes all of the service related information except for the information included in the first discovery signal among the service related information. Discovery signal transmission device made with.
The method of claim 11,

The service related information is transmitted from a network entity supporting the terminal-to-terminal communication, an identifier of the transmitting terminal for performing the terminal-to-terminal communication, and an identifier of an application related to the terminal-to-terminal communication. And at least one of an identifier of the transmitting terminal related to the application and interest information of the transmitting terminal.
The method of claim 11,

The first discovery signal resource and the second discovery signal resource is a discovery signal transmission apparatus characterized in that the frequency or time position is changed based on at least one of a predetermined period, the subframe and the slot in which the discovery signal is transmitted.
The method of claim 11,

The size of the second discovery signal resource is determined according to the first discovery signal resource.
In the receiving signal receiving apparatus of the receiving terminal for terminal-to-terminal communication,

Receiving a first discovery signal of the transmitting terminal generated based on information related to a service provided through the terminal-to-terminal communication through a preset first discovery signal transmission resource, and determining the first discovery signal from the first discovery signal transmission resource. A discovery signal receiver for receiving a second discovery signal of the transmitting terminal through a discovery signal transmission resource; And

By comparing the first discovery signal information of the transmitting terminal detected from the received first discovery signal and the service-related information of the receiving terminal stored in advance, the first discovery signal information of the transmitting terminal is added to the service-related information of the receiving terminal. If so, the second discovery signal transmission resource is determined from the first discovery signal transmission resource, and the second discovery signal information of the transmitting terminal and the service related information of the receiving terminal detected from the received second discovery signal. And comparing the second discovery signal information of the transmitting terminal with the service related information of the receiving terminal, and controlling the terminal to perform the terminal-to-terminal communication operation for the transmitting terminal. Receiving device.
The method of claim 16,

The first discovery signal includes a part of the service related information, and the second discovery signal includes all or the service related information except for the information included in the first discovery signal among the service related information. Discovery signal receiving device.
The method of claim 16,

The service related information is transmitted from a network entity supporting the terminal-to-terminal communication, an identifier of a terminal for performing the terminal-to-terminal communication, an identifier of an application related to the terminal-to-terminal communication, and And at least one of an identifier of the terminal associated with an application and the interest information of the terminal.
The method of claim 16,

And the first discovery signal resource and the second discovery signal resource are changed in frequency or time position based on at least one of a predetermined period, a subframe in which the discovery signal is transmitted, and a slot.
The method of claim 16,

The controller may further determine the size of the second discovery signal resource according to the first discovery signal resource.