KR20150056073A - Apparatus and method for performing a handover in communication system supporting device to device scheme - Google Patents

Abstract

The present invention relates to A method for performing a handover by a user equipment (UE) in a communication system supporting a device to device (D2D) scheme. The method includes receiving a direct connection reconfiguration message from an enhanced node B (eNB), wherein the direct connection reconfiguration message includes information on each of direct connections of the UE, and wherein the information on each of the direct connection includes a UE identifier (ID) and connection parameters.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an apparatus and a method for performing a handover in a communication system supporting a device-

The present invention relates to an apparatus and a method for performing a handover in a communication system supporting a device to device (D2D) scheme.

In a communication system supporting the D2D scheme, two devices, for example, a user equipment (UE), can search each other, and between the two devices Direct communication can be established.

Referring to FIG. 1, in a communication system supporting a general D2D scheme, two UEs are connected to an enhanced Node B (eNB) or a direct communication service provided by a base station The operation scenario will be described.

1 is a diagram schematically illustrating an operation scenario for direct communication in which two UEs are served by the same eNB in a communication system supporting a general D2D scheme.

Referring to FIG. 1, the communication system includes an eNB 111, a UE # 1 113, and a UE # 2 115. The UE # 1 113 and the UE # 2 115 are included in a UE pair.

The UE # 1 113 and the UE # 2 115 included in the UE pair transmit a downlink (DL) frequency F1 and an uplink (UL) (Hereinafter referred to as " UL ") frequency. Here, the UL frequency F2 is used for direct communication between the UEs included in the UE pair, i.e., the UE # 1 113 and the UE # 2 115. At the UL frequency F2, resources are controlled by the eNB 111. [

FIG. 1 illustrates an operation scenario for direct communication in which two UEs are served by the same eNB in a communication system supporting a general D2D scheme. Next, in the service coverage of the eNB, UE-eNB communication and UE The mechanisms for enabling-UE communication are as follows.

a) a cell radio network temporary identifier (C-RNTI) (hereinafter referred to as C-RNTI) for UE-eNB communication and UE-UE communication,

Other C-RNTIs are allocated by the eNB for the UE-eNB communication and UE-UE communication from the same address space. The C-RNTI is allocated to the UE pair for the UE-UE communication. Also, the C-RNTI is used to identify resources for the UE-eNB communication and resources for UE-UE communication. Here, information on resources for the UE-eNB communication and information on resources for UE-UE communication are transmitted through UEs belonging to the UE pair through a single control channel using a C-RNTI assigned to the UE pair Lt; / RTI >

b) a C-RNTI reserved for UE-UE communication of all UE pairs and a UE pair ID for each UE pair

The C-RNTI is reserved from the C-RNTI address space and indicates information about resources for all UE-UE communication pairs in the eNB's service coverage. Also, a new UE ID pair is assigned to each UE pair by the eNB, and the UE pair ID identifies the corresponding UE pair from another UE pair. That is, the UE pair ID is used to identify a UE pair. Further, information on resources is transmitted to UEs included in the corresponding UE pair through a single control channel using a reserved C-RNTI and a UE pair ID assigned to the corresponding UE pair.

c) a unified C-RNTI for UE-eNB communication and UE-UE communication and a C-RNTI exchange between UEs included in the UE pair

For each UE, the type of communication, i.e., the communication between each UE and the eNB, or the communication between each UE and another UE, or the communication between each UE and the eNB and the communication between each UE and another UE One C-RNTI is allocated. For the UEs included in the UE pair, the C-RNTIs for the UEs are known to each other during direct connection establishment. The C-RNTI for one of the UEs included in the UE pair is used in the control channel to signal resource allocation information for direct communication. It should be noted that, in this way, it is assumed that time intervals for direct communication are specially reserved.

The mechanisms described above provide ways to identify UE pair communication performed in the service coverage of the eNB from communication between the eNB and other UEs (the other UEs are not involved in direct communication).

Also, in the service coverage of the eNB, the schemes for identifying the UE pair communication from the communication between the eNB and other UEs identify the UE pair communication from the communication between the eNB and the UEs included in the UE pair. Also, in the service coverage of the eNB, the methods of identifying the UE pair communication from the communication between the eNB and other UEs identify any UE pair communication from other UE pair communication.

Recently, a user association for device-to-device (D2D) direct communication disclosed in 3GPP TSG RAN WG1 meeting # 73 of Fukuoka, Japan on May 20-24, 2013, R1-131990 ' Based on the simulation results published in "User Association for Device to Device (D2D) Direct Communication, R1-131990" published in 3GPP TSG RAN WG1 Meeting # 73 Fukuoka, Japan, May 20-24, 2013 ' It has been discussed that direct links between UEs belonging to cells are feasible. In fact, in certain scenarios, the direct links between the UEs belonging to the other cells are more dominant.

Referring to FIG. 2, an example of a relationship between the number of D2D links and a reference signal received power (RSRP) threshold value in a communication system supporting a general D2D scheme Will be described.

2 is a diagram schematically illustrating an example of a relationship between the number of D2D links and a RSRP threshold value in a communication system supporting a general D2D scheme.

Referring to FIG. 2, the graph shown in FIG. 2 is 'User association for device to device (D2D) direct communication, R1-131990' published in 3GPP TSG RAN WG1 Meeting # 73 Fukuoka, Japan, May 20-24, 2013 'Is the simulation graph presented in'

In particular, the graph shown in FIG. 2 shows a carrier frequency of 2 GHz, an infrastructure service discovery (ISD) of 500 m, an inter-cell (ISD) The relationship between the number of D2D links and the RSRP threshold when considering the D2D link and the intra-cell D2D link.

If the RSRP threshold value is too large, in one case, in the case of the RSRP threshold value having the RSRP threshold value of any value within the range of -80 to 100 dBm, the formed D2D links are not sufficiently present, As shown, relatively many UEs do not search for any pairing UE for a D2D link association.

However, if the RSRP threshold is less than -110 dBm and -110 dBm, then almost all UEs will be associated with D2D link associations.

Also shown in FIG. 2 is the ratio of inter-cell D2D links or intra-cell D2D links among all D2D links. The intra-cell D2D link represents a D2D link between two UEs in the same cell, and the inter-cell D2D link represents a D2D link between two UEs in other cells.

Also, for a relatively high RSRP threshold, as shown in FIG. 2, the number of intra-cell D2D links is greater than the number of inter-cell D2D links. However, if the RSRP threshold value is less than a predetermined RSRP threshold value, for example, -110 dBm, it is known that the inter-cell D2D link is dominant, and the lower the RSRP threshold value, Will become even more powerful.

FIG. 2 illustrates an example of a relationship between the number of D2D links and the RSRP threshold in a communication system supporting a general D2D scheme. Referring to FIG. 3, the number of D2D links in a communication system supporting a general D2D scheme And the RSRP threshold value will be described.

3 is a diagram schematically showing another example of the relationship between the number of D2D links and the RSRP threshold in a communication system supporting a general D2D scheme.

Referring to FIG. 3, the graph shown in FIG. 3 is 'User association for device to device (D2D) direct communication, R1-131990' published in 3GPP TSG RAN WG1 Meeting # 73 Fukuoka, Japan, May 20-24, 2013 'Is the simulation graph presented in'

In particular, the graph shown in FIG. 3 shows the relationship between the number of D2D links and the RSRP threshold when considering 700 MHz carrier frequency, 1732 m ISD, inter-cell D2D link and intra-cell D2D link.

If the RSRP threshold value is too large, in one case, in case of the RSRP threshold value having any value within the range of -80 to 100 dBm, the formed D2D links are not sufficiently present, A relatively large number of UEs do not search for any pairing UE for the D2D link association.

However, if the RSRP threshold is less than -110 dBm and -110 dBm, then almost all UEs will be associated with D2D link associations.

In addition, FIG. 3 shows the ratio of inter-cell D2D links or intra-cell D2D links among all D2D links. The intra-cell D2D link represents a D2D link between two UEs in the same cell, and the inter-cell D2D link represents a D2D link between two UEs in other cells.

Also, for a relatively high RSRP threshold, as shown in FIG. 3, the number of intra-cell D2D links is greater than the number of inter-cell D2D links. However, if the RSRP threshold value is less than a predetermined RSRP threshold value, for example, -110 dBm, it will be known that the inter-cell D2D link is dominant, and the lower the RSRP threshold value, It will be powerful.

FIG. 3 illustrates another example of the relationship between the number of D2D links and the RSRP threshold in a communication system supporting a general D2D scheme. Referring to FIG. 4, in a communication system supporting a general D2D scheme, An example of a core issue for resource allocation for communication will be described.

4 is a diagram schematically illustrating an example of a core issue for resource allocation for inter-cell D2D communication in a communication system supporting a general D2D scheme.

4, the communication system includes eNB # 1 411, eNB # 2 413, UE # 1 415, UE # 2 417, UE # 3 419, UE # 4 421, UE # 5 423, UE # 6 425, UE # 7 427, UE # 8 429 and UE # 9 431.

The first issue for allocating resources for the intercell D2D communication is that the resources for communication between the UEs included in the UE pair in the service coverage of the eNB # 1 411 and the service coverage of the eNB # (In control signaling) and resources for other UEs.

The first issue example identifies resources for communication of the UE # 1-UE # 2 pair and resources for the UE # 3 419 in the service coverage of the eNB # 1 411, 2 413 in the service coverage of the UE # 4 421.

The second issue for the resource allocation for the inter-cell D2D communication is that the resources (in control signaling) for communication of the UE pair and the resources of the eNBs (eNB # 1 411 and eNB # 1 413) To identify the resources of the UEs included in the UE pair for communication.

An example of the second issue is to identify resources for communication of UE # 1-UE # 2 pair and resources for UE # 1-eNB # 1 (or UE # 2-eNB # 2) communication.

The third issue for resource allocation for the inter-cell D2D communication is that resources (in control signaling) for communication in any UE pair and resources for communication in another UE pair (in the eNB # 1 411) In service coverage, or in service coverage of the eNB # 2 413, or in both the service coverage of the eNB # 1 411 and the service coverage of the eNB # 2 413).

An example of the third issue is to identify resources for communication of the UE # 1-UE # 2 pair and resources for communication of the UE # 5-UE # 6 pair in the service coverage of the eNB # 1 411 (UE) # 2 413 and the eNB # 2 413, and identifying resources for communication of the UE # 7-UE # 8 pair in the service coverage of the eNB # 2 413, Lt; RTI ID = 0.0 > UE # 9-UE # 10 < / RTI >

FIG. 4 illustrates an example of a core issue for allocating resources for intercell D2D communication in a communication system supporting a general D2D scheme. Next, referring to FIG. 5, in a communication system supporting a general D2D scheme, Other examples of key issues for resource allocation for D2D communication will be described.

FIG. 5 is a diagram schematically illustrating another example of core issues for resource allocation for intercell D2D communication in a communication system supporting a general D2D scheme.

Referring to FIG. 5, a first issue for allocating resources for intercell D2D communication is to adjust resources between eNBs for direct communication. A second issue for resource allocation for intercell D2D communication is the resource allocation for UEs included in the UE pair for each transmitting / receiving (TX / RX, hereinafter referred to as TX / RX) Signaling the allocation information.

For example, it is assumed that a resource for a UE # 1-UE # 2 pair is allocated in a UL sub-frame (SF) #n.

In this case, how the information on resources allocated in the UL SF # n is signaled to both UE # 1 and UE # 2 becomes a second issue for resource allocation for the inter-cell D2D communication.

A third issue for resource allocation for inter-cell D2D communication is to identify the TX / RX role between the UEs included in the UE pair during direct communication.

The fourth issue for resource allocation for inter-cell D2D communication is to identify the transmission resources of UE # 1 and the reception resources of UE # 2 with the reception resources of UE # 1 and the transmission resources of UE # 2.

As an example, resources for the UE # 1-UE # 2 pair are allocated in UL SF # n.

In this case, the UE # 1 must perform a transmission operation through the resources allocated in the UL SF # n, and the UE # 2 must perform the reception operation through the resources allocated in the UL SF # n.

Therefore, for the UL SF # n, the UE # 1 must be in the TX mode and the UE # 2 must be in the RX mode.

As another example, resources for the UE # 1-UE # 2 pair are allocated in UL SF # n + 2.

In this case, the UE # 1 must perform a transmission operation through the resources allocated in the UL SF # n + 2, and the UE # 2 performs a reception operation through the resources allocated in the UL SF # must do it.

Therefore, for the UL SF # n + 2, the UE # 2 must be in the TX mode and the UE # 1 must be in the RX mode.

As described above, the communication system supporting the D2D scheme supports the inter-cell D2D communication and the intra-cell D2D communication, and accordingly, in the inter-cell D2D communication and the intra-cell D2D communication, And UE-UE communication and UE-eNB communication. However, in the communication system supporting the D2D scheme, a concrete method for accurately identifying the UE, the UE pair, the UE-UE communication and the UE-eNB communication according to the situation in the inter-cell D2D communication and the intra-cell D2D communication I have not been presented.

Also, as described above, the communication system supporting the D2D scheme must be implemented considering various issues related to the resource allocation operation. However, in the communication system supporting the D2D scheme, there is no specific scheme for allocating resources in consideration of various issues as described above.

During direct communication between UE # 1 and UE # 2 associated with other eNBs, the eNBs cooperate to allocate resources for the direct communication. Also, a logical connection is established between the eNBs in establishing a direct connection. One or two UEs involved in direct communication may be mobile. As a result, during the direct communication between the UEs, the association of the UEs associated with the eNBs is continuously changed. Some of the possible scenarios are:

One. UE # A and UE # B are associated with eNB # 1 before handover. After the handover, the UE # A is associated with the eNB # 1, and the UE # B is associated with the eNB # 2.

2. UE # A and UE # B are associated with eNB # 1 before handover. After the handover, the UE # A is associated with eNB # 3, and the UE # B is associated with eNB # 2.

3. UE # A and UE # B are associated with eNB # 1 before handover. After the handover, the UE # A and the UE # B are associated with the eNB # 2.

4. UE # A and UE # B are associated with eNB # 1 and eNB # 2 before handover, respectively. After the handover, the UEs #A and #B are associated with the eNB # 1.

5. UE # A and UE # B are associated with eNB # 1 and eNB # 2 before handover, respectively. After the handover, the UE # A and the UE # B are associated with the eNB # 3.

6. UE # A and UE # B are associated with eNB # 1 and eNB # 2 before handover, respectively. After the handover, the UEs #A and #B are associated with the eNB # 1 and the eNB # 3, respectively.

7. UE # A and UE # B are associated with eNB # 1 and eNB # 2 before handover, respectively. After the handover, UE # A and UE # B are associated with eNB # 3 and eNB # 4, respectively.

As a result of mobility, when a UE moves from a serving eNB to a target eNB during direct communication, the following needs to be performed:

a) The target eNB needs to establish a connection with the eNB (s) of the UE (s) in direct communication with the UE.

b) The serving eNB needs to disconnect the eNB (s) of the UE (s) to which the UE was directly communicating.

c) The target eNB needs to disconnect from the serving eNB for connection of the UE and other UEs.

d) The UEs involved in direct communication need to acquire new connection parameters.

In addition, in the communication system supporting the D2D scheme, there is no specific scheme related to the handover considering the contents described in the above a) to d).

On the other hand, the above information is only presented as background information to help understand the present invention. No determination has been made as to whether any of the above content is applicable as prior art to the present invention, nor is any claim made.

An embodiment of the present invention proposes an apparatus and method for performing a handover in a communication system supporting the D2D scheme.

In addition, an embodiment of the present invention proposes an apparatus and method for transmitting / receiving signals in a communication system supporting the D2D scheme.

In addition, an embodiment of the present invention proposes an apparatus and method for transmitting / receiving signals for direct connection in a communication system supporting the D2D scheme.

In addition, an embodiment of the present invention proposes an apparatus and method for transmitting / receiving a signal in consideration of a communication type in a communication system supporting the D2D scheme.

In addition, an embodiment of the present invention proposes an apparatus and method for transmitting / receiving a signal related to direct connection establishment in a communication system supporting the D2D scheme.

In addition, an embodiment of the present invention proposes an apparatus and method for transmitting / receiving signals related to resource allocation in a communication system supporting the D2D scheme.

In addition, an embodiment of the present invention proposes an apparatus and method for transmitting / receiving a signal related to a resource type in a communication system supporting the D2D scheme.

Also, an embodiment of the present invention proposes an apparatus and method for transmitting / receiving a signal related to a UE that uses resources allocated in a communication system supporting the D2D scheme.

In addition, an embodiment of the present invention proposes an apparatus and method for transmitting / receiving a signal related to a communication type using resources allocated in a communication system supporting the D2D scheme.

In addition, an embodiment of the present invention proposes an apparatus and method for transmitting / receiving a signal related to handover in a communication system supporting the D2D scheme.

In addition, an embodiment of the present invention proposes an apparatus and method for transmitting / receiving a signal related to a handover in consideration of a communication type in a communication system supporting the D2D scheme.

A method proposed in an embodiment of the present invention comprises: A method for performing a handover by a user equipment (UE) in a communication system supporting a device to device (D2D) scheme, the method comprising: receiving a direct connection reconfiguration message from an enhanced Node B (eNB) Wherein the direct connection reconfiguration message includes information on each of the direct connections of the UE and the information on each of the direct connections includes a UE identifier and connection parameters .

Another method proposed in an embodiment of the present invention comprises: 1. A method for supporting handover in an enhanced Node B (eNB) in a communication system supporting a device to device (D2D) scheme, the method comprising: transmitting, by a user equipment (UE) And transmitting a direct connection handover request message to the other eNB, wherein the direct connection handover request message includes information on each of the direct connections of the UE, And information on each of the direct connections includes a UE identifier and connection parameters.

Another method proposed in an embodiment of the present invention is to: A method for supporting handover by an enhanced Node B (eNB) in a communication system supporting a device to device (D2D) scheme, comprising the steps of: receiving a direct connection handover request message from another eNB; Wherein the direct connection handover request message includes information on each of the direct connections of the UE and information on each of the direct connections includes a UE identifier and connection parameters, .

An apparatus proposed in an embodiment of the present invention comprises: A receiver for receiving a direct reconfiguration message from an enhanced Node B (eNB) in a user equipment (UE) in a communication system supporting a device to device (D2D) scheme, , The direct connection reconfiguration message includes information on each of the direct connections of the UE, and the information on each of the direct connections includes a UE identifier (ID) and connection parameters.

Another apparatus proposed in an embodiment of the present invention includes: It is necessary for a user equipment (UE) to perform handover to another eNB in an enhanced Node B (eNB) in a communication system supporting a device to device (D2D) scheme And a transmitter for transmitting a direct connection handover request message to the other eNB, wherein the direct connection handover request message includes information on each of the direct connections of the UE, Information includes a UE identifier (ID) and connection parameters.

Another apparatus proposed in an embodiment of the present invention comprises: A Node B (eNB) enhanced in a communication system supporting a device to device (D2D) scheme, comprising: a receiver for receiving a direct connection handover request message from another eNB, The handover request message includes information on each of the direct connections of the UE, and information on each of the direct connections includes a UE identifier (ID) and connection parameters.

Other aspects, benefits, and key features of the present invention will become apparent to those skilled in the art from the following detailed description, which is set forth in the accompanying drawings and which discloses preferred embodiments of the invention.

It may be effective to define definitions for certain words and phrases used throughout this patent document before processing the specific description portions of the present disclosure below: " include " and " Comprise " and its derivatives mean inclusive inclusion; The term "or" is inclusive and means "and / or"; The terms " associated with " and " associated therewith ", as well as derivatives thereof, are included within, included within, I do not want to be in a relationship with you. I do not want to be in a relationship with you. to communicate with, be communicable with, cooperate with, interleave, juxtapose, proximate to, to communicate with, It is likely to be or be bound to or with, have a property of, etc .; The term " controller " means any device, system, or portion thereof that controls at least one operation, such devices may be hardware, firmware or software, or some combination of at least two of the hardware, Lt; / RTI > It should be noted that the functionality associated with any particular controller may be centralized or distributed, and may be local or remote. Definitions for particular words and phrases are provided throughout this patent document and those skilled in the art will recognize that such definitions are not only conventional, But also to future uses of the phrases.

An embodiment of the present invention is advantageous in that handover can be performed in a communication system supporting the D2D scheme.

In addition, an embodiment of the present invention has an effect that a signal can be transmitted / received in a communication system supporting the D2D scheme.

In addition, an embodiment of the present invention has an effect that a signal for direct connection can be transmitted / received in a communication system supporting the D2D scheme.

In addition, an embodiment of the present invention has an effect that it is possible to transmit / receive a signal in consideration of a communication type in a communication system supporting the D2D scheme.

In addition, an embodiment of the present invention has an effect that it is possible to transmit / receive a signal related to direct connection establishment in a communication system supporting the D2D scheme.

In addition, an embodiment of the present invention has an effect that a signal related to resource allocation can be transmitted / received in a communication system supporting the D2D scheme.

In addition, an embodiment of the present invention has an effect that it is possible to transmit / receive a signal related to a resource type in a communication system supporting the D2D scheme.

In addition, an embodiment of the present invention has an effect that it is possible to transmit / receive a signal related to a UE to use a resource allocated in a communication system supporting the D2D scheme.

In addition, an embodiment of the present invention has an effect that it is possible to transmit / receive a signal related to a communication type using resources allocated in a communication system supporting the D2D scheme.

In addition, an embodiment of the present invention has an effect that a signal related to handover can be transmitted / received in a communication system supporting the D2D scheme.

In addition, an embodiment of the present invention has an effect of enabling a signal related to handover to be transmitted / received in consideration of a communication type in a communication system supporting the D2D scheme.

Further aspects, features and advantages of the present invention as set forth above in connection with certain preferred embodiments thereof will become more apparent from the following description, taken in conjunction with the accompanying drawings, in which:
1 is a diagram schematically illustrating an operation scenario for direct communication in which two UEs are served by the same eNB in a communication system supporting a general D2D scheme;
2 is a diagram schematically illustrating an example of a relationship between the number of D2D links and an RSRP threshold in a communication system supporting a general D2D scheme;
3 is a diagram schematically illustrating another example of the relationship between the number of D2D links and the RSRP threshold in a communication system supporting a general D2D scheme;
4 is a diagram schematically illustrating an example of core issues for resource allocation for inter-cell D2D communication in a communication system supporting a general D2D scheme;
5 is a view schematically showing another example of core issues for resource allocation for intercell D2D communication in a communication system supporting a general D2D scheme;
6 is a diagram schematically illustrating an example of a process of transmitting resource allocation information to UEs included in a UE pair for intercell direct communication in a communication system supporting the D2D scheme according to an embodiment of the present invention. Flow diagram;
7 is a diagram schematically showing another example of a process of transmitting resource allocation information to UEs included in a UE pair for direct cell direct communication in a communication system supporting the D2D scheme according to an embodiment of the present invention to be;
8 is a diagram schematically illustrating an example of a process of transmitting resource allocation information to UEs included in a UE pair for intra-cell direct communication in a communication system supporting the D2D scheme according to an embodiment of the present invention to be;
9 is a diagram schematically showing another example of a process of transmitting resource allocation information to UEs included in a UE pair for intra-cell direct communication in a communication system supporting the D2D scheme according to an embodiment of the present invention to be;
10 is a diagram schematically illustrating an example of an inter-cell direct connection establishment process and a Tx-Idx / Rx-Idx assignment process in a communication system supporting the D2D scheme according to an embodiment of the present invention;
11 is a diagram schematically illustrating another example of an inter-cell direct connection establishment process and a Tx-Idx / Rx-Idx assignment process in a communication system supporting the D2D scheme according to an embodiment of the present invention;
12 is a diagram schematically illustrating another example of an inter-cell direct connection establishment process and a Tx-Idx / Rx-Idx assignment process in a communication system supporting the D2D scheme according to an embodiment of the present invention;
FIG. 13 is a diagram schematically illustrating an intra-cell direct connection establishment process and a Tx-Idx / Rx-Idx assignment process in a communication system supporting the D2D scheme according to an embodiment of the present invention;
FIG. 14 is a diagram schematically illustrating another example of an intra-cell direct connection establishment process and a Tx-Idx / Rx-Idx assignment process in a communication system supporting the D2D scheme according to an embodiment of the present invention;
15 is a diagram schematically showing another example of a process of transmitting resource allocation information to UEs included in a UE pair for inter-cell direct communication in a communication system supporting the D2D scheme according to an embodiment of the present invention. One drawing;
16 is a diagram schematically illustrating another example of a procedure for transmitting resource allocation information to UEs included in a UE pair for inter-cell direct communication in a communication system supporting the D2D scheme according to an embodiment of the present invention. One drawing;
17 is a diagram schematically illustrating a handover process when a UE performs handover from an eNB to another eNB during direct communication with another UE in a communication system supporting the D2D scheme according to an embodiment of the present invention;
18A to 18B are signal flow diagrams schematically illustrating a handover process in scenario # 1 in a communication system supporting the D2D scheme according to an embodiment of the present invention;
19A to 19B are signal flow diagrams schematically illustrating a handover process in scenario # 2 in a communication system supporting the D2D scheme according to an embodiment of the present invention;
20 is a signal flow diagram schematically illustrating a handover process in scenario # 3 in a communication system supporting the D2D scheme according to an embodiment of the present invention;
21 is a signal flow diagram schematically illustrating a handover process in scenario # 4 in a communication system supporting the D2D scheme according to an embodiment of the present invention;
22 is a diagram schematically illustrating an internal structure of a UE in a communication system supporting the D2D scheme according to an embodiment of the present invention;
23 is a diagram schematically illustrating an internal structure of an eNB in a communication system supporting the D2D scheme according to an embodiment of the present invention;
24 is a diagram schematically illustrating an internal structure of an MME in a communication system supporting the D2D scheme according to an embodiment of the present invention.
Throughout the drawings, it should be noted that like reference numerals are used to illustrate the same or similar elements and features and structures.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be noted that only the parts necessary for understanding the operation according to the embodiments of the present invention will be described below, and the description of the other parts will be omitted so as not to disturb the gist of the present invention. The following terms are defined in consideration of the functions in the embodiments of the present invention, and may be changed according to the intention of the user, the intention or the custom of the operator. Therefore, the definition should be based on the contents throughout this specification.

The present invention is capable of various modifications and various embodiments, and specific embodiments thereof will be described in detail with reference to the drawings. It should be understood, however, that the invention is not intended to be limited to the particular embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

It is also to be understood that the singular forms "a" and "an" above, which do not expressly state otherwise in this specification, include plural representations. Thus, in one example, a " component surface " includes one or more component representations.

Also, terms including ordinal numbers such as first, second, etc. may be used to describe various elements, but the elements are not limited to these terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component. And / or < / RTI > includes any combination of a plurality of related listed items or any of a plurality of related listed items.

Also, the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, the terms "comprises" or "having" and the like refer to the presence of stated features, integers, steps, operations, elements, components, or combinations thereof, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

Furthermore, in the embodiments of the present invention, all terms used herein, including technical or scientific terms, unless otherwise defined, are intended to be inclusive in a manner that is generally understood by those of ordinary skill in the art to which this invention belongs. Have the same meaning. Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the contextual meaning of the related art and, unless explicitly defined in the embodiments of the present invention, are intended to mean ideal or overly formal .

According to various embodiments of the invention, the electronic device may comprise a communication function. For example, the electronic device may be a smart phone, a tablet personal computer (PC), a mobile phone, a videophone, an e-book reader e a notebook PC, a netbook PC, a personal digital assistant (PDA), a portable personal computer (PC) A mobile multimedia device, a portable multimedia player (PMP), an MP3 player, a mobile medical device, a camera, a wearable device (e.g., a head- Electronic devices such as a head-mounted device (HMD), an electronic apparel, an electronic bracelet, an electronic necklace, an electronic app apparel, an electronic tattoo, or a smart watch ) And the like.

According to various embodiments of the present invention, the electronic device may be a smart home appliance having communication capabilities. For example, the smart home appliance includes a television, a digital video disk (DVD) player, audio, a refrigerator, an air conditioner, a vacuum cleaner, an oven, A microwave oven, a washer, a dryer, an air purifier, a set-top box, a TV box (for example, Samsung HomeSync ^™ , Apple TV ^™ or Google TV ^™ ) a gaming console, an electronic dictionary, a camcorder, an electrophotographic frame, and the like.

According to various embodiments of the present invention, the electronic device may be a medical device (e.g., magnetic resonance angiography (MRA) device, magnetic resonance imaging (CT) device, an imaging device, or an ultrasonic device), a navigation device, and a magnetic resonance imaging (MRI) , A global positioning system (GPS) receiver, an event data recorder (EDR), a flight data recorder a recorder: FDR (hereinafter referred to as FER), an automotive infotainment device, a navigation electronic device (for example, a navigation navigation device, A gyroscope, or a compass), an avionics device, a secure device, an industrial or consumer robot, and the like.

In accordance with various embodiments of the present invention, an electronic device includes a plurality of devices, including furniture, a portion of a building / structure, an electronic board, an electronic signature receiving device, a projector and various measurement devices (e.g., Water, electricity, gas or electromagnetic wave measuring devices), and the like.

According to various embodiments of the invention, the electronic device may be a combination of devices as described above. It should also be apparent to those skilled in the art that the electronic device according to the preferred embodiments of the present invention is not limited to the device as described above.

According to various embodiments of the present invention, a user equipment (UE) may be an electronic device, for example.

One embodiment of the present invention proposes an apparatus and method for performing a handover in a communication system supporting a device-to-device (D2D) scheme.

In addition, an embodiment of the present invention proposes an apparatus and method for transmitting / receiving signals in a communication system supporting the D2D scheme.

In addition, an embodiment of the present invention proposes an apparatus and method for transmitting / receiving signals for direct connection in a communication system supporting the D2D scheme.

In addition, an embodiment of the present invention proposes an apparatus and method for transmitting / receiving a signal in consideration of a communication type in a communication system supporting the D2D scheme.

In addition, an embodiment of the present invention proposes an apparatus and method for transmitting / receiving a signal related to direct connection establishment in a communication system supporting the D2D scheme.

In addition, an embodiment of the present invention proposes an apparatus and method for transmitting / receiving signals related to resource allocation in a communication system supporting the D2D scheme.

In addition, an embodiment of the present invention proposes an apparatus and method for transmitting / receiving a signal related to a resource type in a communication system supporting the D2D scheme.

Also, an embodiment of the present invention proposes an apparatus and method for transmitting / receiving a signal related to a UE that uses resources allocated in a communication system supporting the D2D scheme.

In addition, an embodiment of the present invention proposes an apparatus and method for transmitting / receiving a signal related to a communication type using resources allocated in a communication system supporting the D2D scheme.

In addition, an embodiment of the present invention proposes an apparatus and method for transmitting / receiving a signal related to handover in a communication system supporting the D2D scheme.

In addition, an embodiment of the present invention proposes an apparatus and method for transmitting / receiving a signal related to a handover in consideration of a communication type in a communication system supporting the D2D scheme.

Meanwhile, the method and apparatus proposed in an embodiment of the present invention may be applied to an IEEE 802.16ac communication system, an IEEE 802.16 communication system, an IEEE 802.16 communication system, A digital multimedia broadcasting (DMB) service, a digital video broadcasting-handheld (DVP-H, hereinafter referred to as DVP-H) service, And mobile broadcasting services such as the advanced television systems committee-mobile / handheld (ATSC-M / H) service (hereinafter referred to as ATSC-M / H) a digital video broadcasting system such as an internet protocol television (IPTV) service, an moving picture experts group (MPEG) media transport (MMT) system, an evolved packet system (EPS), a long-term evolution (LTE) system, (LTE-A) mobile communication system, a long-term evolution-advanced (LTE-A) mobile communication system, A high speed downlink packet access (HSDPA) mobile communication system, a high speed uplink packet access (HSUPA) Speed packet data (HRPD) (hereinafter referred to as 'HRPD') of a 3rd generation project partnership 2 (3GPP2, hereinafter referred to as 3GPP2) Mobile communication system, and 3GPP2 (WCDMA) mobile communication system and a code division multiple access (CDMA) system of 3GPP2 (hereinafter referred to as " CDMA " ) Mobile communication system, a communication system such as an Institute of Electrical and Electronics Engineers (IEEE) mobile communication system, a mobile internet protocol (Mobile IP) (Hereinafter referred to as " Mobile IP ") system.

First, a resource allocation scheme proposed in an embodiment of the present invention will be described as follows.

First, an enhanced Node B (eNB), which is associated with UEs included in a user equipment (UE) pair, And determines resources for direct communication between the UEs included in the UE pair in cooperation with each other. The information about the determined resources is then signaled to each UE independently. For example, for a UE pair including UE # 1 and UE # 2, in which UE # 1 belongs to eNB # 1 and UE # 2 belongs to eNB # 2, the eNB # 1 for direct communication between the UE # 1 and the UE # 2, while the eNB # 2 signals the UE # 1 about the determined resources for direct communication between the UE # 1 and the UE # To the UE # 2. Here, the resources can be determined for each packet transmission in a direct link. In addition, the resources may be determined in a semi-fixed manner as an example, and the determined resources are valid for a plurality of transmission time periods. In addition, the resources may be determined in a fixed manner, for example, and the determined resources are valid for a duration of a connection between the UE # 1 and the UE # 2.

Here, signaling for resource allocation will be described in detail as follows.

First, information on resources for direct communication between UEs included in a UE pair is transmitted by an eNB at a downlink (DL) frequency.

First, in the control region at the DL frequency, not only for communication with the eNB, but also information about the resources for the direct communication is transmitted.

Also, for direct communication, information about resources is transmitted independently to the UEs included in the UE pair.

In addition, information on the resources is transmitted to each UE included in the UE pair by an eNB for each UE included in the UE pair.

In addition, the eNB associated with the UEs included in the UE pair includes a control channel for transmitting resource allocation information to UEs included in the UE pair, for example, a physical downlink control channel (PDCCH) (Hereinafter, referred to as PDCCH) signal. In one embodiment of the present invention, the control channel for transmitting the resource allocation information is a PDCCH. However, it is needless to say that the control channel for transmitting the resource allocation information may be another channel as well as the PDCCH.

In addition, a UE identifier for the UE, for example, a cell radio network temporary identifier (C-RNTI) (hereinafter referred to as C-RNTI), is encoded in the control channel. In one embodiment of the present invention, the UE identifier is a C-RNTI, but the UE identifier may be an identifier other than the C-RNTI. In an embodiment of the present invention, a cyclic redundancy check (CRC) for the control channel is masked using the UE identifier.

For example, UE # 1, which includes UE # 1 belonging to eNB # 1 and UE # 2 belonging to eNB # 2, and information about allocated resources needs to be signaled, 2 pair, the UE # 1 uses the allocated resources for transmission, and the UE # 2 uses the allocated resources for reception. The eNB # 1 transmits an arbitrary PDCCH signal to the UE # 1 in order for the UE # 1 to perform a transmission operation and to transmit information on the allocated resources in which the UE # 2 performs a reception operation While the eNB # 2 transmits another PDCCH signal to the UE # 2. The PDCCH signal transmitted by the eNB # 1 is CRC masked using the C-RNTI of the UE # 1. Also, the PDCCH signal transmitted by the eNB # 2 is CRC masked using the C-RNTI of the UE # 2. Both the PDCCH transmitted by the eNB # 1 and the PDCCH transmitted by the eNB # 2 may be transmitted in the same DL subframe or may be transmitted in other DL subframes.

In another example, a UE pair, i.e., UE # 1 and UE # 2 belonging to eNB # 1 include eNB # 1, and a UE # 1-UE # 2 pair in which information on allocated resources needs to be signaled If considered, the UE # 1 uses the allocated resources for transmission and the UE # 2 uses the allocated resources for reception. Here, the UE # 1 performs a transmission operation, and the eNB # 1 transmits an arbitrary PDCCH signal to the UE # 1 in order to transmit information on the allocated resources in which the UE # 2 performs a reception operation And transmits another PDCCH signal to the UE # 2. The first PDCCH signal transmitted by the eNB # 1 is CRC masked using the C-RNTI of the UE # 1. The second PDCCH signal transmitted by the eNB # 1 is CRC-masked using the C-RNTI of the UE # 2. Here, both of the PDCCH signals transmitted by the eNB # 1 may be transmitted in the same DL subframe, or may be transmitted in other DL subframes.

Hereinafter, a method of identifying the communication related to the allocated resources will be described.

First, each UE may be communicating with one UE or more UEs, and may also be in communication with the eNB. When the UE receives and decodes a masked control channel (e.g., a PDCCH) signal using the C-RNTI of the UE, the UE determines whether the corresponding resource is for direct communication or the corresponding resource communicates with the eNB Or to determine whether or not to do so.

Herein, the UE is specifically described with respect to each of the methods # 1, # 2, and # 3 for determining whether the corresponding resource is for direct communication or for communicating with the eNB. Then,

First, the method # 1 will be described as follows.

First, information on resources for communication between the UE and the eNB and information on resources for communication between the UE and other UEs are transmitted in different DL subframes. The UE recognizes information on subframes transmitting information on resources for communication between the UE and the eNB. In addition, the UE recognizes information on subframes transmitting information on resources for communication between the UE and other UEs.

As an example, consider the case where an uplink (UL) frequency is used for direct communication. Information about resources at the UL frequency for direct communication and information about resources at the UL frequency for communication with the eNB are signaled in other DL subframes. Thus, the UE may determine resources for each type of communication using a single C-RNTI of the UE.

Secondly, the method # 2 will be described as follows.

the downlink control information transmitted in the control channel to indicate resources for direct communication with the format of the downlink control information transmitted in the control channel (e.g., PDCCH) to indicate resources for communication with the eNB The formats are different. The size of the downlink control information transmitted in the PDCCH to indicate the resources for the direct communication is different from the sizes of the existing downlink control information formats. Thus, when the UE receives and decodes the control channel signal, the UE can know whether the downlink control information is for indicating the resources for the direct communication.

Thirdly, the method # 3 will be described as follows.

The UE may be assigned other C-RNTIs for communication with the eNB and for communication with other UEs. Accordingly, the eNB and the UE will use the C-RNTI allocated for direct communication with a control channel (for example, a PDCCH) that transmits information on resources for direct communication. Therefore, the eNB will use the C-RNTI allocated for the direct communication in a control channel conveying information about the resources for the direct communication. Also, the eNB may use a C-RNTI allocated for eNB communication in a control channel (for example, a PDCCH) for transmitting information on resources for eNB communication.

In the above description, the methods # 1, # 2, and # 3 for determining whether the corresponding resource is for direct communication or whether the corresponding resource is for communicating with the eNB, , A method of identifying a resource for transmission and a resource for reception in a communication system supporting the D2D scheme according to an embodiment of the present invention will be described.

First, when the UE receives information on resources allocated for direct communication, the UE needs to determine whether the resources allocated for the direct communication are resources for transmission or resources for reception. A method for determining whether a resource allocated for direct communication according to an embodiment of the present invention is a resource for transmission or a resource for reception is as follows.

First, the eNB adds a 1-bit transmitting_receiving_indicator (Tx_Rx_indicator, hereinafter referred to as Tx_Rx_indicator) to a control channel signal for transmitting resource allocation information. Here, the Tx_Rx_indicator is an indicator indicating whether the corresponding resource is a transmission resource or a reception resource.

(1) When Tx_Rx_indicator is set to 1 (Tx_Rx_indicator = 1), this indicates that the resource is a transmission resource.

(2) When Tx_Rx_indicator is set to 0 (Tx_Rx_indicator = 0), it indicates that the resource is a receiving resource.

In an embodiment of the present invention, the Tx_Rx_indicator is implemented with 1 bit. However, it is needless to say that the Tx_Rx_indicator may be implemented with a plurality of bits.

If the UE receives a control channel signal for transmitting resource allocation information using the UE identifier of the UE, for example, the C-RNTI, and the Tx_Rx_indicator is set to 0 in the received control channel signal, It can be known that the resources corresponding to the resource allocation information are the reception resources, and thus the reception operation is performed in the resources corresponding to the resource allocation information.

Alternatively, when the Tx_Rx_indicator is set to '1' in the received control channel signal, the UE can recognize that the resources corresponding to the resource allocation information are transmission resources, and thus the resource corresponding to the resource allocation information Lt; / RTI >

Also, the Tx_Rx_indicator may be included in the control channel for transmitting the resource allocation information in the form of an information field, or may generate a cyclic redundancy check (CRC) for the control channel And may be included in a CRC mask used to do so.

In the above description, a method of determining whether a resource allocated for direct communication in a communication system supporting the D2D scheme according to an embodiment of the present invention is a resource for transmission or a resource for reception has been described. A method for identifying a transmitter and a receiver when a transmission resource and a reception resource are allocated to a UE in a communication system supporting the D2D scheme according to an embodiment of the present invention will be described.

First, a first scheme for identifying a transmitter and a receiver when a transmission resource and a reception resource are allocated to a UE in a communication system supporting the D2D scheme according to an embodiment of the present invention will be described.

(1) a method of identifying the transmitter when the UE is allocated a receiving resource

First, each UE may be connected to a plurality of UEs. When transmission resources are allocated to the UE, the UE needs to determine which UE and the allocated transmission resources should be used to perform a transmission operation. In an embodiment of the present invention, a method for determining to which UE a UE should perform a transmission operation using transmission resources allocated to the UE itself will be described in detail.

First, a receiving index (Rx_idx, hereinafter referred to as Rx_idx) is allocated to each UE when a direct connection is established.

The Rx_idx is an identifier for identifying a plurality of UEs to which the corresponding UE is receiving data.

For example, it is assumed that UE # 1 is connected to UE # 2 and UE # 3. The UE # 1 receives data from the UE # 2 and the UE # 3.

For the connection between the UE # 1 and the UE # 2, the UE # 1 is assigned Rx_idx whose value is 0 (Rx_idx = 0).

For the connection between the UE # 1 and the UE # 3, the UE # 1 is assigned Rx_idx whose value is 1 (Rx_idx = 1).

If any UE receives a control channel signal using the C-RNTI of the UE and the Tx_Rx_indicator is set to 0, the UE receives from the resources corresponding to the resource allocation information included in the control channel signal Operation.

The Rx_idx may be included in the control channel, and the Rx_idx in the control channel is used to identify the transmitter.

The Rx_idx may be included as an information field in the control channel, or may be included in a CRC mask.

The Rx_idx is unique in a plurality of connections between other UEs and the UE. That is, the Rx_idx is maintained independently for each UE.

(2) a method of identifying a receiver when a transmission resource is allocated to the UE

First, each UE may be connected to a plurality of UEs. When UEs are allocated receiving resources, the UE needs to determine which UE should perform the receiving operation using the allocated receiving resources. A method for a UE to determine a UE that should perform a receiving operation using received resources allocated to the UE in an embodiment of the present invention will be described in detail as follows.

First, a transmitting index (Tx_idx, hereinafter referred to as Tx_idx) is allocated to each UE when a direct connection is established.

The Tx_idx identifies a plurality of UEs to which the UE is transmitting data.

For example, assume that UE # 1 is connected to UE # 2 and UE # 3, and data is transmitted to UE # 2 and UE # 3.

For the connection between the UE # 1 and the UE # 2, the UE # 1 is assigned Tx_idx whose value is 0 (Tx_idx = 0).

For the connection between the UE # 1 and the UE # 3, the UE # 1 is assigned Tx_idx whose value is 1 (Tx_idx = 1).

When an arbitrary UE receives a control channel signal using the UE identifier of the UE and Tx_Rx_indicator is set to 1, the UE performs a transmission operation in resources corresponding to the resource allocation information included in the control channel signal, .

The control channel signal is used to identify a UE to which the UE should transmit data.

The Tx_idx may be included as an information field in the control channel, or may be included in a CRC mask.

The Tx_idx is unique in a plurality of connections between other UEs and a UE. That is, the Tx_idx is maintained independently for each UE.

6 and 7, a process of transmitting resource allocation information to UEs included in a UE pair for intercell direct communication in a communication system supporting the D2D scheme according to an embodiment of the present invention I will explain.

Referring to FIG. 6, an example of a process of transmitting resource allocation information to UEs included in a UE pair for direct cell-to-cell communication in a communication system supporting the D2D scheme according to an embodiment of the present invention I will explain.

6 is a diagram schematically illustrating an example of a process of transmitting resource allocation information to UEs included in a UE pair for intercell direct communication in a communication system supporting the D2D scheme according to an embodiment of the present invention. FIG.

6, the communication system includes a UE # A 611, an eNB # 1 613, an eNB # 2 615, and a UE #B 617.

The UE #A 611 is associated with the eNB # 1 613 and the UE #B 617 is associated with the eNB # 2 615 and a direct connection is established between the UE #A 611 and the UE # #B (617). In the process of establishing the direct connection, the eNB # 1 613 transmits Tx_Idx (Tx_Idx = p) whose value is p and Rx_Idx (Rx_Idx = r) whose value is r for connection with the UE # To the UE # A 611. The UE # During the direct connection establishing process, the eNB # 2 615 transmits Tx_Idx (Tx_Idx = q) whose value is q and Rx_Idx (Rx_Idx = s) whose value is s for connection with the UE # To the UE #B 617 (step 619). Here, the Tx_Idx and Rx_Idx have been described above, and a detailed description thereof will be omitted here.

The eNB # 1 613 and the eNB # 2 615 cooperate with each other to determine resources for direct communication between the UE #A 611 and the UE #B 617 (step 621). For example, the eNB # 1 613 and the eNB # 2 615 decide to use the resources indicated by X, and the UE #A 611 allocates the resources indicated by X to the UE # (617).

The eNB # 1 613 transmits a PDCCH # 1 signal to the UE # A 611 and the CRC for the PDCCH # 1 is masked using the C-RNTI of the UE #A 611 (623 step). In the PDCCH # 1, Tx_Rx_indicator is set to 1, and Tx_Idx is set to p. The PDCCH # 1 signal includes resource allocation information for resources X for direct communication.

The UE # A 611 receives the PDCCH # 1 signal and can decode the PDCCH # 1 signal using the C-RNTI of the UE #A 611. Then, the UE #A 611 transmits the resource allocation information included in the PDCCH # 1 signal for transmission to the UE #B 617 based on the Tx_Rx_indicator and the Tx_Idx It is determined to use the corresponding resources (Step 625). That is, the Tx_Rx_indicator whose value is set to 1 indicates to the UE # A 611 that the corresponding resources are transmission resources. Also, when Tx_Idx whose value is set to p is allocated to the UE # A 611 for connection with the UE #B 617, the UE #A 611 transmits the resources to the UE #B 617 ≪ / RTI > Meanwhile, the UE #A 611 performs a transmission operation using the determined transmission resources (step 627).

Meanwhile, the eNB # 2 615 transmits a PDCCH # 2 signal to the UE #B 617, and the CRC for the PDCCH # 2 is masked using the C-RNTI of the UE #B 617 (Step 629). In the PDCCH # 2 signal, Tx_Rx_indicator is set to 0, and Rx_Idx is set to q. The PDCCH # 2 signal includes information about the resources X for direct communication. The UE #B 617 may receive the PDCCH # 2 signal and may decode the PDCCH # 2 signal using the C-RNTI of the UE #B 617. Then, the UE #B 617 determines to use resources corresponding to the resource allocation information included in the PDCCH # 2 for reception from the UE #A based on the Tx_Rx_indicator and Rx_Idx (631 step).

On the other hand, the Tx_Rx_indicator set to 0 indicates that the corresponding resources are for reception. When Rx_Idx whose value is set to q is allocated to the UE #B 617 for connection with the UE #A 611, the UE #B 617 determines that the resources are resources for reception . Meanwhile, the UE #B 617 performs a receiving operation using the determined resources (step 633).

That is, the same resources are indicated by the eNB # 1 613 using the PDCCH # 1 and indicated by the eNB # 2 615 using the PDCCH # 2, Transmits the packet to the UE #B 617 (step 635).

6 shows an example of a process of transmitting resource allocation information to UEs included in a UE pair for direct cell direct communication in a communication system supporting the D2D scheme according to an embodiment of the present invention , Various modifications may be made with respect to FIG. As an example, although successive steps are shown in FIG. 6, it is understood that the steps described in FIG. 6 may overlap, occur in parallel, occur in different orders, or occur multiple times.

6, an example of a process of transmitting resource allocation information to UEs included in a UE pair for intercell direct communication in a communication system supporting the D2D scheme according to an embodiment of the present invention has been described, Another example of a process of transmitting resource allocation information to UEs included in a UE pair for intercell direct communication in a communication system supporting the D2D scheme according to an embodiment of the present invention will be described with reference to FIG. .

7 is a diagram schematically showing another example of a process of transmitting resource allocation information to UEs included in a UE pair for direct cell direct communication in a communication system supporting the D2D scheme according to an embodiment of the present invention to be.

7, the communication system includes a UE # A 711, an eNB # 1 713, an eNB # 2 715, and a UE #B 717.

A 711 is associated with the eNB # 1 713 and the UE B 717 is associated with the eNB # 2 715 and a direct connection is established between the UE #A 711 and the UE # #B (717). In the process of establishing the direct connection, the eNB # 1 713 transmits Tx_Idx (Tx_Idx = p) whose value is p and Rx_Idx (Rx_Idx = r) whose value is r for connection with the UE # ) To the UE # A (711). During the direct connection establishing process, the eNB # 2 715 transmits Tx_Idx (Tx_Idx = q) whose value is q and Rx_Idx (Rx_Idx = s) whose value is s for connection with the UE # To the UE #B 717 (step 719). Here, the Tx_Idx and Rx_Idx have been described above, and a detailed description thereof will be omitted here.

The eNB # 1 713 and the eNB # 2 715 cooperate with each other to determine resources for direct communication between the UE #A 711 and the UE #B 717 (step 721). For example, the eNB # 1 713 and the eNB # 2 715 decide to use the resources indicated by Y, and the UE # A 711 allocates resources to the UE # (717).

The eNB # 2 715 transmits a PDCCH # 3 signal to the UE #B 717 and the CRC for the PDCCH # 3 signal is masked using the C-RNTI of the UE #B 717 729). In the PDCCH # 3 signal, Tx_Rx_indicator is set to 1, and Tx_Idx is set to s. The PDCCH # 3 signal includes resource allocation information for the resources Y for direct communication.

The UE #B 717 may receive the PDCCH # 3 signal and may decode the PDCCH # 3 signal using the C-RNTI of the UE #B 717. Then, the UE #B 717 receives the resource allocation information corresponding to the resource allocation information included in the PDCCH # 3 signal for transmission to the UE #A 711 using the Tx_Rx_indicator and Tx_Idx. (Step 731).

In addition, the Tx_Rx indicator set to 1 indicates to the UE #B 717 that the corresponding resources are for transmission. s 711 is allocated to the UE # B 717 for connection with the UE # A 711, the UE #B 717 allocates resources for transmission to the UE #A 711, . Meanwhile, the UE #B 717 performs a transmission operation using the determined transmission resources (step 733).

Meanwhile, the eNB # 1 713 transmits a PDCCH # 4 signal and the CRC for the PDCCH # 4 signal is masked using the C-RNTI of the UE #A 711 (step 723). In the PDCCH # 4 signal, Tx_Rx_indicator is set to 0, and Rx_Idx is set to r. The PDCCH # 4 signal includes resource allocation information for the resources Y for direct communication. The UE # A 711 may receive the PDCCH # 4 signal and may decode the PDCCH # 4 signal using the C-RNTI of the UE #A 711. Then, the UE # A 711 uses the resources corresponding to the resource allocation information included in the PDCCH # 4 signal for reception from the UE #B 717 using the Tx_Rx_indicator and Rx_Idx (Step 725).

Also, a Tx_Rx_indicator set to 0 indicates that the resources are resources for reception. s Rx_Idx is allocated to the UE # A 711 for connection with the UE #B 717 when the same Rx_Idx is allocated to the UE #B 717 ≪ / RTI > Meanwhile, the UE # A 711 performs a receiving operation using the determined resources (Step 727).

That is, the same resources are indicated by the eNB # 1 713 using the PDCCH # 3 and indicated by the eNB # 2 715 using the PDCCH # 4, Transmits the packet to the UE # A 711 (step 735).

Meanwhile, FIG. 7 shows another example of a process of transmitting resource allocation information to UEs included in a UE pair for intercell direct communication in a communication system supporting a D2D scheme according to an embodiment of the present invention Various modifications may be made with respect to FIG. In one example, although the steps are shown in FIG. 7, the steps described in FIG. 7 may overlap, occur in parallel, occur in different orders, or occur multiple times.

7, another example of a process of transmitting resource allocation information to UEs included in a UE pair for intercell direct communication in a communication system supporting the D2D scheme according to an embodiment of the present invention has been described, A process of transmitting resource allocation information to UEs included in a UE pair for intra-cell direct communication in a communication system supporting the D2D scheme according to an embodiment of the present invention will be described with reference to FIGS. 8 and 9 .

Referring to FIG. 8, an example of a process of transmitting resource allocation information to UEs included in a UE pair for intra-cell direct communication in a communication system supporting the D2D scheme according to an embodiment of the present invention I will explain.

8 is a diagram schematically illustrating an example of a process of transmitting resource allocation information to UEs included in a UE pair for intra-cell direct communication in a communication system supporting the D2D scheme according to an embodiment of the present invention to be.

8, the communication system includes a UE # A 811, a UE # B 813, and an eNB 815.

The UE #A 811 and the UE #B 813 are associated with the same eNB, that is, the eNB 815, and a direct connection is established between the UE #A 811 and the UE #B 813. During the process of establishing the direct connection, the eNB 815 sends Tx_Idx (Tx_Idx = p) whose value is p and Rx_Idx (Tx_Idx = p) whose value is r to UE # A 811 for connection with UE # (Rx_Idx = r) (step 817). During the direct connection establishing process, the eNB 815 sends to the UE #B 813 a Tx_Idx (Tx_Idx = q) whose value is q and an Rx_Idx (Rx_Idx = s). Since Tx_Idx and Rx_Idx have been described above, detailed description thereof will be omitted here.

The eNB 815 determines resources for direct communication between the UE #A 811 and the UE #B 813. In one example, the eNB 815 decides to use resources indicated as 'X'. Here, the UE #A 811 performs a transmission operation from the resources X to the UE #B 813. The eNB 815 transmits a PDCCH # 1 signal to the UE #A 811 where the CRC for the PDCCH # 1 signal is masked using the C-RNTI of the UE #A 811 (819 step). In the PDCCH # 1 signal, Tx_Rx_indicator is set to 1, and Tx_Idx is set to p. The PDCCH # 1 signal includes resource allocation information for the resources X for direct communication.

The UE # A 811 receives the PDCCH # 1 signal and can decode the PDCCH # 1 signal using the C-RNTI of the UE #A 811. Then, the UE #A 811 decides to use the resources corresponding to the resource allocation information included in the PDCCH # 1 signal for transmission to the UE #B 813 using the Tx_Rx_indicator and the Tx_Idx (Step 821).

Also, a Tx_Rx_indicator set to 0 indicates to the UE #A 811 that resources are resources for transmission. Also, when Tx_Idx set to p is allocated to the UE #A 811 for connection with the UE #B 813, it is determined that the resources are transmission resources for transmission to the UE #B 813. Meanwhile, the UE #A 811 performs a transmission operation using the determined transmission resources (step 823).

Also, the eNB 815 transmits a PDCCH # 2 signal to the UE #B 813 and the CRC for the PDCCH # 2 signal is masked using the C-RNTI of the UE #B 813 825). In the PDCCH # 2 signal, Tx_Rx_indicator is set to 0, and Rx_Idx is set to q. The PDCCH # 2 signal includes resource allocation information for the resources X for direct communication. The UE #B 813 may receive the PDCCH # 2 signal and may decode the PDCCH # 2 signal using the C-RNTI of the UE #B 813. Then, the UE #B 813 uses the resources corresponding to the resource allocation information included in the PDCCH # 2 signal for reception from the UE #A 811 using the Tx_Rx_indicator and Rx_Idx (Step 827).

Also, a Tx_Rx_indicator set to 0 indicates that the resources are resources for reception. Also, when Rx_Idx set to q is allocated to the UE #B 813, the UE #B 813 determines that the resources are the resources for reception. Meanwhile, the UE #B 813 performs a receiving operation using the determined resources (step 829).

That is, the same resources are indicated by the eNB 815 on the PDCCH # 1 and the PDCCH # 2, so that the UE #A 811 transmits the packet to the UE #B 813 (step 831).

Meanwhile, FIG. 8 shows an example of a process of transmitting resource allocation information to UEs included in a UE pair for intra-cell direct communication in a communication system supporting the D2D scheme according to an embodiment of the present invention Various variations may be made with respect to Fig. As an example, although consecutive steps are shown in FIG. 8, it is understood that the steps described in FIG. 8 may overlap, occur in parallel, occur in different orders, or occur multiple times.

8, an example of a process of transmitting resource allocation information to UEs included in a UE pair for intra-cell direct communication in a communication system supporting the D2D scheme according to an embodiment of the present invention has been described. Another example of a process of transmitting resource allocation information to UEs included in a UE pair for intra-cell direct communication in a communication system supporting the D2D scheme according to an embodiment of the present invention will be described with reference to FIG. .

9 is a diagram schematically showing another example of a process of transmitting resource allocation information to UEs included in a UE pair for intra-cell direct communication in a communication system supporting the D2D scheme according to an embodiment of the present invention to be.

9, the communication system includes a UE # A 911, a UE # B 913, and an eNB 915.

The UE #A 911 and the UE #B 913 are associated with the same eNB, eNB 915, and a direct connection is established between the UE #A 911 and the UE #B 913. During the process of establishing the direct connection, the eNB 915 sends to the UE # A 911 a Tx_Idx (Tx_Idx = p) whose value is p and an Rx_Idx (Rx_Idx = r) is allocated (step 917). During the direct connection establishing process, the eNB 915 transmits to the UE #B 913 a Tx_Idx (Tx_Idx = q) whose value is q and an Rx_Idx (Rx_Idx = s). Since Tx_Idx and Rx_Idx have been described above, detailed description thereof will be omitted here.

The eNB 915 determines resources for direct communication between the UE #A 911 and the UE #B 913. For example, the eNB 915 decides to use the resources indicated by Y, and the UE #B 913 performs a transmission operation from the resources Y to the UE #A 911.

The eNB 915 transmits a PDCCH # 3 signal to the UE #B 913 and the CRC for the PDCCH # 3 signal is masked using the C-RNTI of the UE #B 913 (step 919 ). In the PDCCH # 3 signal, Tx_Rx_indicator is set to 1, and Tx_Idx is set to s. The PDCCH # 3 signal carries resource allocation information for the resources Y for direct communication. The UE #B 913 may receive the PDCCH # 3 signal and may decode the PDCCH # 3 signal using the C-RNTI of the UE #B 913. Then, the UE #B 913 determines to use the resources indicated in the PDCCH # 3 signal for transmission to the UE #A 911 using the Tx_Rx_indicator and Tx_Idx in step 921.

Also, a Tx_Rx_indicator set to 1 indicates to the UE #B 913 that the corresponding resources are transmission resources. s Tx_Idx is determined to be resources for transmission to the UE #A 911 when the same Tx_Idx as the s is allocated to the UE #B 913 for connection with the UE #A 911 do. Meanwhile, the UE #B 913 performs a transmission operation using the determined transmission resources (step 923).

Also, the eNB 915 transmits a PDCCH # 4 signal and the CRC for the PDCCH # 4 signal is masked using the C-RNTI of the UE #A 911 (step 925). In the PDCCH # 4 signal, Tx_Rx_indicator is set to 0, and Rx_Idx is set to r. The PDCCH # 4 signal includes resource allocation information for the resources Y for direct communication. The UE #A 911 receives the PDCCH # 4 signal and can decode the PDCCH # 4 signal using the C-RNTI of the UE #A 911. Then, the UE #A 911 determines to use the resources indicated in the PDCCH # 4 signal for reception from the UE #B 913 using the Tx_Rx_indicator and the Rx_Idx in step 927.

In addition, the Tx_Rx_indicator set to 0 indicates that the resources are reception resources. s 911 is allocated to the UE #A 911, the UE # A 911 determines that the corresponding resources are reception resources for reception from the UE #B 913. In step 929, the UE # A 911 performs a reception operation using the determined resources.

That is, the same resources are indicated by the eNB 915 on the PDCCH # 3 and the PDCCH # 4, and thus the UE #B 913 transmits the packet to the UE #A 911 (step 931).

9 shows another example of a process of transmitting resource allocation information to UEs included in a UE pair for intra-cell direct communication in a communication system supporting the D2D scheme according to an embodiment of the present invention , It is understood that various modifications can be made with respect to FIG. As an example, although successive steps are shown in FIG. 9, it is understood that the steps described in FIG. 9 may overlap, occur in parallel, occur in different orders, or occur multiple times.

9, another example of a procedure for transmitting resource allocation information to UEs included in a UE pair for intra-cell direct communication in a communication system supporting the D2D scheme according to an embodiment of the present invention has been described, An inter-cell direct connection establishment and a Tx-Idx / Rx-Idx assignment process in a communication system supporting the D2D scheme according to an embodiment of the present invention will be described with reference to FIG. 10 and FIG. Here, the inter-cell direct connection establishment and Tx-Idx / Rx-Idx assignment processes as shown in FIGS. 10 and 11 are performed by establishing an inter-cell direct connection and assigning Tx-Idx and Rx-Idx , The inter-cell direct connection establishment and the Tx-Idx / Rx-Idx assignment process can be implemented in various ways as well as the schemes shown in FIG. 10 and FIG.

10 is a diagram schematically illustrating an example of an inter-cell direct connection establishment process and a Tx-Idx / Rx-Idx assignment process in a communication system supporting the D2D method according to an embodiment of the present invention.

10, the communication system includes a UE # A 1011, an eNB # 1 1013, a mobility management entity (MME) 1015, eNB # 2 (1017).

The inter-cell direct connection establishment and the Tx-Idx / Rx-Idx assignment process shown in FIG. 10 are performed when the UE # A 1011 searches for UE #B (not shown in FIG. 10) It is noted that the inter-cell direct connection establishment and the Tx-Idx / Rx-Idx allocation process when triggering the establishment of the inter-cell connection are triggered.

The UE #A 1011 transmits a direct communication request message to the eNB to which the UE #A 1011 is attached, that is, the eNB # 1 1013 (Step 1019) . The UE #A 1011 includes a UE identifier (ID) (hereinafter, referred to as 'ID') of the UE #B in the direct communication request message. In an embodiment of the present invention, the UE ID may be an ID assigned to the UE for proximity-based service (ProSe) communication, for example, a ProSe UE ID. In addition, the UE ID includes an idle mode ID assigned to the UE, for example, a system architecture evolution (SAE) temporary mobile subscriber identity (SAE) TMSI (hereinafter, referred to as "T-S-TMSI"). In another embodiment of the present invention, the UE ID may be a globally unique temporary identifier (GUTI) assigned to the UE. In an embodiment of the present invention, the UE # A 1011 searches for the UE ID of the UE #B while searching for the UE #B. Also, the UE #A 1011 may include the UE ID of the UE #A 1011 in the direct communication request message. Upon receiving the direct communication request message from the UE #A 1011, the eNB # 1 1013 authenticates the direct communication request message and transmits a direct communication request message including the UE ID of the UE #B 1011 To the MME 1015 (step 1021).

The MME 1015 receiving the direct communication request message from the eNB # 1 1013 determines the cell / eNB of the UE #B in step 1023. When the UE # A 1011 and the UE # B are in an idle mode and the UE B exists under the same MME as the UE #A 1011, the MME 1015 transmits the UE # B, so the UE #B transitions from the idle mode to the connected mode, and the UE #B is associated with the cell or eNB.

Alternatively, when the UE #A 1011 and the UE #B exist in the connected mode, if the UE #A 1011 and the UE #B exist under the same MME, the MME 1015 transmits the UE # We know the cell of B. If the UE #B does not exist under the same MME as the UE #A 1011, the MME 1015 contacts the MME of the UE #B to determine the cell of the UE #B. When determining the cell of the UE #B, the MME 1015 transmits a direct communication response message, which is a response message to the direct communication request message, to the eNB # 1 1013 (step 1025) .

Information on the cell / eNB information is included in the direct communication response message. Then, the eNB # 1 1013 allocates Tx-Idx and Rx-Idx to the UE #A 1011. Then, the eNB # 1 1013 transmits a direct communication response message including the Tx-Idx and the Rx-Idx allocated to the UE #A 1011 to the UE #A 1011, (Step 1027). Also, the eNB # 1 1013 includes the C-RNTI of the UE #A 1011 in the direct communication response message. In an embodiment of the present invention, the C-RNTI of the UE #A 1011 may be included in the direct communication response message when the C-RNTI is newly allocated to the UE #A 1011. If the C-RNTI is not allocated to the UE #A 1011, the eNB # 1 1013 allocates the C-RNTI to the UE #A 1011. [ The eNB # 1 1013 may include other parameters related to direct communication in the direct communication response message.

Upon receiving the direct communication response message from the eNB # 1 1013, the UE # A 1011 transmits a direct communication complete message, which is a response message to the direct communication response message, to the eNB # (Step 1029). Then, the UE # A 1011 starts using the allocated C-RNTI and Tx-Idx and Rx-Idx. Since the C-RNTI, Tx-Idx, and Rx-Idx have been described above, detailed description thereof will be omitted here.

After receiving the direct communication completion message from each of the UE #A 1011 and the UE #B, the eNB # 1 1013 and the eNB # 2 1017 transmit resources for UE # A-UE # ENB < / RTI > interface (step 1031).

10 illustrates an example of an inter-cell direct connection establishment process and a Tx-Idx / Rx-Idx assignment process in a communication system supporting the D2D scheme according to an embodiment of the present invention. Of course. In one example, although successive steps are shown in FIG. 10, it is understood that the steps described in FIG. 10 may overlap, occur in parallel, occur in different orders, or occur multiple times.

10, an example of an inter-cell direct connection establishment process and a Tx-Idx / Rx-Idx assignment process in a communication system supporting the D2D scheme according to an embodiment of the present invention has been described. Another example of an inter-cell direct connection establishment and a Tx-Idx / Rx-Idx allocation process in a communication system supporting the D2D scheme according to an embodiment of the present invention will be described.

11 is a diagram schematically illustrating another example of an inter-cell direct connection establishment process and a Tx-Idx / Rx-Idx assignment process in a communication system supporting the D2D method according to an embodiment of the present invention.

11, the communication system includes a UE # B 1111, an eNB # 1 1113, an MME 1115, and an eNB # 2 1117.

The inter-cell direct connection establishment and the Tx-Idx / Rx-Idx assignment process shown in FIG. 11 are performed by the MME 1115 in order to establish a direct connection with the UE #A (not shown in FIG. 11) Lt; RTI ID = 0.0 > Tx-Idx / Rx-Idx < / RTI >

First, the MME 1115 is triggered when the MME 1115 receives a communication request message directly from the eNB or another MME. For example, when the UE #A and the UE #B 1111 exist under the same MME, the MME 1115 transmits the communication request message to the MME 1115 when the MME 1115 receives a communication request message directly from the eNB # and triggers the eNB # 1 1113. For example, when the UE #A and the UE #B 1111 are under another MME, the MME 1115 is triggered when the MME 1115 receives a communication request message directly from the MME of the UE #A. Accordingly, the MME 1115 transmits a direct communication request message to the eNB # 2 1117 (step 1119).

The MME 1115 includes the UE IDs of UE #A and UE # 1111 in the direct communication request message. Also, the MME 1115 includes cell / eNB information of the UE #A in the direct communication request message. Upon receiving the direct communication request message, the eNB # 2 1117 allocates Tx-Idx and Rx-Idx to the UE #B 1111. The eNB # 2 1117 includes the Tx-Idx and the Rx-Idx of the allocated UE #B 1111 in the direct communication response message, which is a response message to the direct communication request message, (Step 1121). Also, the eNB # 2 1117 includes the C-RNTI of the UE #B 1111 in the direct communication response message.

In an embodiment of the present invention, the C-RNTI of the UE #B 1111 may be included in the direct communication response message only when the C-RNTI is newly allocated to the UE #B 1111. If the C-RNTI is not allocated to the UE #B 1111, the eNB # 2 1117 allocates the C-RNTI to the UE #B 1111. [ The eNB # 2 1117 may include other parameters related to direct communication in the direct communication response message. Upon receiving the direct communication response message, the UE # B 1111 transmits a direct communication completion message, which is a response message to the direct communication response message, to the eNB # 2 1117 (step 1123). Then, the UE #B 1111 starts using the allocated C-RNTI and Tx-Idx and Rx-Idx. Since the C-RNTI, Tx-Idx, and Rx-Idx have been described above, detailed description thereof will be omitted here.

The eNB # 2 1117 having received the direct communication complete message from the UE #B 1111 directly transmits a communication response message to the MME 1115 in step 1125. After receiving the direct communication complete message from each of the UEs #A and #B 1111, the eNB # 1 1113 and the eNB # 2 1117 transmit resources for UE # A-UE # And exchanges signaling at the eNB-eNB interface to adjust (step 1127).

Meanwhile, in another embodiment of the present invention, the Tx-Idx and Rx-Idx are maintained by the UE itself. The UE allocates Tx-Idx and Rx-Idx for connection between another UE and the UE, and transmits the allocated Tx-Idx and Rx-Idx to the eNB during the direct connection establishment process. The eNB uses the Tx-Idx and Rx-Idx to store the Tx-Idx and Rx-Idx and transmit the PDCCH signal to the UE. The Tx-Idx and Rx-Idx may be transmitted by the UE to the eNB in the form of a direct communication request message for a direct communication complete message. Here, it should be noted that the characteristics of Tx-Idx and Rx-Idx are the same regardless of whether the Tx-Idx and Rx-Idx are allocated by the eNB or the UE.

For example, when the eNB allocates the Tx-Idx and the Rx-Idx, the eNB must maintain information on Tx-Idx and Rx-Idx already allocated to the connections of the UE, the eNB must keep information on Tx-Idx and Rx-Idx already allocated for all UEs.

As another example, when the UE allocates the Tx-Idx and Rx-Idx, the UE must maintain information on Tx-Idx and Rx-Idx that are already allocated to the connection of the UE, The load of the eNB is reduced.

11 shows another example of an inter-cell direct connection establishment process and a Tx-Idx / Rx-Idx assignment process in a communication system supporting the D2D scheme according to an embodiment of the present invention, Of course. In one example, although the sequential steps are shown in FIG. 11, it is understood that the steps described in FIG. 11 may overlap, occur in parallel, occur in different orders, or occur multiple times.

11, another example of an inter-cell direct connection establishment and a Tx-Idx / Rx-Idx assignment process in a communication system supporting the D2D scheme according to an embodiment of the present invention has been described. Another example of an inter-cell direct connection establishment and a Tx-Idx / Rx-Idx assignment process in a communication system supporting the D2D scheme according to an embodiment of the present invention will be described. Here, the inter-cell direct connection establishment and the Tx-Idx / Rx-Idx assignment process as shown in FIG. 12 is an example of establishing an inter-cell direct connection and allocating Tx-Idx and Rx- The inter-cell direct connection establishment and the Tx-Idx / Rx-Idx assignment process may be implemented in various ways as well as the method shown in FIG.

12 is a diagram schematically illustrating another example of an inter-cell direct connection establishment process and a Tx-Idx / Rx-Idx assignment process in a communication system supporting the D2D method according to an embodiment of the present invention.

12, the communication system includes a UE # A 1211, a UE # B 1213, an eNB # 1 1215, and an eNB # 2 1217.

First, the UE #A 1211 starts a process of establishing a direct communication with the UE #B 1213. That is, the UE #A 1211 transmits a direct communication request message including the UE ID of the UE #A 1211 to the UE #B 1213 in step 1219. Here, the UE ID may be an ID specific to the D2D communication, or may be another UE ID. In an embodiment of the present invention, the UE ID may be an ID allocated to the UE #A 1211 for ProSe communication, for example, a ProSe UE ID. In another embodiment of the present invention, the UE ID may be the idle mode ID assigned to the UE #A 1211, e.g., S-TMSI. In another embodiment of the present invention, the UE ID may be a GUTI allocated to the UE #A 1211. [ When receiving the direct communication request message from the UE #A 1211, the UE #B 1213 receives the direct communication request message from the UE #A 1211, ID 1211 to the UE #A 1211 (step 1221).

Then, the UE #A 1211 and the UE #B 1213 respectively transmit a direct communication request message to the eNB # 1 1215 and the eNB # 2 1217 (steps 1223 and 1225). Here, the UE #A 1211 is associated with the eNB # 1 1215 and the UE #B 1213 is associated with the eNB # 2 1217. The UE #A 1211 includes the UE ID of the UE #A 1211 in the direct communication request message and the UE #B 1213 transmits the UE ID of the UE #B 1213 to the direct communication Include in the request message. It should be noted that there is no limitation on the order in which the UE #A 1211 and the UE #B 1213 transmit the direct communication request message to the corresponding eNB.

When receiving the direct communication request message from the UE #A 1211, the eNB # 1 1215 authenticates the direct communication request message and informs the UE #A 1211 of Tx-Idx and Rx-Idx . The eNB # 1 1215 transmits Tx-Idx and Rx-Idx allocated to the UE # A 1211 in a direct communication response message, which is a response message to the direct communication request message, in step 1227. Also, the eNB # 1 1215 includes the C-RNTI of the UE #A 1211 in the direct communication response message. In an embodiment of the present invention, the C-RNTI of the UE #A 1211 may be included in the direct communication response message only when the C-RNTI is newly allocated to the UE #A 1211. If the C-RNTI is not allocated to the UE #A 1211, the eNB # 1 1215 allocates the C-RNTI to the UE #A 1211. The eNB # 1 1215 may include other parameters related to direct communication in the direct communication response message.

On the other hand, when receiving the direct communication request message from the UE #B 1213, the eNB # 2 1217 authenticates the direct communication request message and informs the UE #B 1213 of Tx-Idx and Rx Allocate -Idx. The eNB # 2 1217 transmits Tx-Idx and Rx-Idx allocated to the UE #B 1213 to the direct communication response message, which is a response message to the direct communication request message, in step 1229. Also, the eNB # 2 1217 includes the C-RNTI of the UE #B 1213 in the direct communication response message. In an embodiment of the present invention, the C-RNTI of the UE #B 1213 may be included in the direct communication response message when the C-RNTI is newly allocated to the UE #B 1213. When the C-RNTI is not allocated to the UE #B 1213, the eNB # 2 1217 allocates the C-RNTI to the UE #B 1213.

On the other hand, when receiving the direct communication response message from the eNB # 1 1215, the UE #A 1211 directly transmits a communication completion message to the eNB # 1 1215 in step 1231. Upon receiving the direct communication response message from the eNB # 2 1217, the UE #B 1213 directly transmits a communication completion message to the eNB # 2 1217 in step 1233. Then, the UE #A 1211 and the UE #B 1213 start using the allocated C-RNTI and Tx-Idx and Rx-Idx. Since the C-RNTI, Tx-Idx, and Rx-Idx have been described above, detailed description thereof will be omitted here.

Meanwhile, in another embodiment of the present invention, the Tx-Idx and Rx-Idx are maintained by the UE itself. The UE allocates Tx-Idx and Rx-Idx for connection between another UE and the UE, and transmits the allocated Tx-Idx and Rx-Idx to the eNB during the direct connection establishment process. The eNB uses the Tx-Idx and Rx-Idx to store the Tx-Idx and Rx-Idx and transmit the PDCCH signal to the UE. The Tx-Idx and Rx-Idx may be transmitted by the UE to the eNB in the form of a direct communication request message for a direct communication complete message. Here, it should be noted that the characteristics of Tx-Idx and Rx-Idx are the same regardless of whether the Tx-Idx and Rx-Idx are allocated by the eNB or the UE.

For example, when the eNB allocates the Tx-Idx and the Rx-Idx, the eNB must maintain information on Tx-Idx and Rx-Idx already allocated to the connections of the UE, the eNB must keep information on Tx-Idx and Rx-Idx already allocated for all UEs.

As another example, when the UE allocates the Tx-Idx and Rx-Idx, the UE must maintain information on Tx-Idx and Rx-Idx that are already allocated to the connection of the UE, The load of the eNB is reduced.

12 shows another example of the inter-cell direct connection establishment and the Tx-Idx / Rx-Idx allocation process in the communication system supporting the D2D scheme according to an embodiment of the present invention. However, 12, for example. In one example, although the sequential steps are shown in FIG. 12, it is understood that the steps described in FIG. 12 may overlap, occur in parallel, occur in different orders, or occur multiple times.

12, another example of an inter-cell direct connection establishment and a Tx-Idx / Rx-Idx assignment process in a communication system supporting the D2D scheme according to an embodiment of the present invention has been described. An example of an intra-cell direct connection establishment process and a Tx-Idx / Rx-Idx assignment process in a communication system supporting the D2D scheme according to an embodiment of the present invention will be described. Here, the intra-cell direct connection establishment and the Tx-Idx / Rx-Idx assignment process as shown in FIG. 13 is an example of establishing an intra-cell direct connection and allocating Tx-Idx and Rx- The intra-cell direct connection establishment process and the Tx-Idx / Rx-Idx assignment process may be implemented in various ways as well as the method shown in FIG.

13 is a diagram schematically illustrating an intra-cell direct connection establishment process and a Tx-Idx / Rx-Idx assignment process in a communication system supporting the D2D scheme according to an embodiment of the present invention.

Referring to FIG. 13, the communication system includes a UE # B 1311, a UE # A 1313, an eNB # 1 1315, and an MME 1317.

The intra-cell direct connection establishment and the Tx-Idx / Rx-Idx assignment process shown in FIG. 13 are the same as the intra-cell connection establishment process shown in FIG. 13 except that when the UE #A 1313 searches for the UE #B 1311 and then triggers a direct connection establishment process, - cell direct connection establishment and Tx-Idx / Rx-Idx assignment process.

First, the UE #A 1313 transmits a direct communication request message to the eNB to which the UE #A 1313 is attached, that is, the eNB # 1 1315 (Step 1319). The UE #A 1313 includes the UE ID of the UE #B 1311 in the direct communication request message. In an embodiment of the present invention, the UE ID may be an ID assigned to the UE # B 1311 for ProSe communication, for example, a ProSe UE ID. In another embodiment of the present invention, the UE ID may be a GUTI assigned to the UE #B 1311. In yet another embodiment of the present invention, the UE #A 1313 searches for the UE ID of the UE #B 1311 during the search process for the UE #B 1311. Also, the UE #A 1313 may include the UE ID of the UE #A 1313 in the direct communication request message. When receiving the direct communication request message from the UE #A 1313, the eNB # 1 1315 authenticates the direct communication request message and performs direct communication including the UE ID of the UE #B 1311 Request message to the MME 1317 (step 1321).

The MME 1317 which has received the direct communication request message from the UE #B 1311 determines the cell / eNB of the UE #B 1311 (step 1323). When the UE #A 1313 and the UE B 1311 exist in the idle mode and the UE #B 1311 exists under the same MME as the UE #A 1313, the MME 1317 The UE #B 1311 will call the UE #B 1311 and therefore the UE #B 1311 transitions to the connected mode and the UE #B 1311 is associated with the cell or the eNB.

When the UE #A 1313 and the UE B 1311 are in the connected mode and the UE #B 1311 has the same UE # A 1311 under the same MME, the MME 1317 And knows the cell of the UE #B 1311. When determining the cell of the UE #B 1311, the MME 1317 transmits a direct communication response message, which is a response message to the direct communication request message, to the eNB # 1 1315 in step 1325. Information on the cell / eNB information is included in the direct communication response message.

Then, the eNB # 1 1315 allocates Tx-Idx and Rx-Idx to the UE #A 1313. The eNB # 1 1315 transmits a direct communication response message including the Tx-Idx and the Rx-Idx allocated to the UE #A 1313 to the UE #A 1313 in step 1327. Also, the eNB # 1 1315 includes the C-RNTI of the UE #A 1313 in the direct communication response message. In an embodiment of the present invention, the C-RNTI of the UE #A 1313 may be included in the direct communication response message when the C-RNTI is newly allocated to the UE # 1313. If the C-RNTI is not allocated to the UE #A 1313, the eNB # 1315 allocates the C-RNTI to the UE #A 1313. The eNB # 1315 may include other parameters related to direct communication in the direct communication response message.

On the other hand, if the cell / eNB information for the UE #B 1311 is the same as the cell / eNB information for the UE #A 1313 after receiving the direct communication response message from the MME 1317, The eNB # 1 1315 allocates Tx-Idx and Rx-Idx to the UE #B 1311. The eNB # 1 1315 transmits a direct communication response message including Tx-Idx and Rx-Idx allocated to the UE #B 1311 to the UE #B 1311 (1329). Also, the eNB # 1 1315 includes the C-RNTI of the UE #B 1311 in the direct communication response.

After receiving the direct communication response message from the MME 1317, if the cell / eNB information for the UE #B 1311 is the same as that of the UE #A 1313, the eNB # 1 (1313) 1315 assign Tx-Idx and Rx-Idx to the UE #B 1311. [ The eNB # 1 1315 transmits a direct communication response message including Tx-Idx and Rx-Idx allocated to the UE #B 1311 to the UE #B 1311 (1329). Also, the eNB # 1 1315 includes the C-RNTI of the UE #B 1311 in the direct communication response.

In an embodiment of the present invention, the C-RNTI of the UE #B 1311 may be included in the direct communication response message when the C-RNTI is newly allocated to the UE #B 1311. If the C-RNTI is not allocated to the UE #B 1311, the eNB # 1315 allocates the C-RNTI to the UE #B 1311. The eNB # 1315 may include other parameters related to direct communication in the direct communication response message.

On the other hand, when receiving the direct communication response message from the eNB # 1 1315, the UE #B 1311 directly transmits a communication completion message to the eNB # 1 1315 in step 1333. Then, the UE #B 1311 starts using the allocated C-RNTI, Tx-Idx, and Rx-Idx. Since the C-RNTI, Tx-Idx, and Rx-Idx have been described above, detailed description thereof will be omitted here.

Meanwhile, in another embodiment of the present invention, the Tx-Idx and Rx-Idx are maintained by the UE itself. The UE allocates Tx-Idx and Rx-Idx for connection between another UE and the UE, and transmits the allocated Tx-Idx and Rx-Idx to the eNB during the direct connection establishment process. The eNB uses the Tx-Idx and Rx-Idx to store the Tx-Idx and Rx-Idx and transmit the PDCCH signal to the UE. The Tx-Idx and Rx-Idx may be transmitted by the UE to the eNB in the form of a direct communication request message for a direct communication complete message. Here, it should be noted that the characteristics of Tx-Idx and Rx-Idx are the same regardless of whether the Tx-Idx and Rx-Idx are allocated by the eNB or the UE.

For example, when the eNB allocates the Tx-Idx and the Rx-Idx, the eNB must maintain information on Tx-Idx and Rx-Idx already allocated to the connections of the UE, the eNB must keep information on Tx-Idx and Rx-Idx already allocated for all UEs.

As another example, when the UE allocates the Tx-Idx and Rx-Idx, the UE must maintain information on Tx-Idx and Rx-Idx that are already allocated to the connection of the UE, The load of the eNB is reduced.

13 shows an example of an intra-cell direct connection establishment process and a Tx-Idx / Rx-Idx assignment process in a communication system supporting the D2D scheme according to an embodiment of the present invention. However, Of course. In one example, although successive steps are shown in FIG. 13, it is understood that the steps described in FIG. 13 may overlap, occur in parallel, occur in different orders, or occur multiple times.

13, an example of an intra-cell direct connection establishment process and a Tx-Idx / Rx-Idx assignment process in a communication system supporting the D2D scheme according to an embodiment of the present invention has been described. Another example of an intra-cell direct connection establishment and a Tx-Idx / Rx-Idx assignment process in a communication system supporting the D2D scheme according to an embodiment of the present invention will be described. Here, the intra-cell direct connection establishment and the Tx-Idx / Rx-Idx assignment process as shown in FIG. 14 is an example of establishing an intra-cell direct connection and allocating Tx-Idx and Rx- The intra-cell direct connection establishment process and the Tx-Idx / Rx-Idx assignment process can be implemented in various ways as well as the method shown in FIG.

14 is a diagram schematically illustrating another example of an intra-cell direct connection establishment process and a Tx-Idx / Rx-Idx assignment process in a communication system supporting the D2D method according to an embodiment of the present invention.

14, the communication system includes a UE # A 1411, a UE # B 1413, and an eNB 1415.

First, the UE #A 1411 starts a process of establishing a direct communication with the UE #B 1413. That is, the UE #A 1411 transmits a direct communication request message including the UE ID of the UE #A 1411 to the UE #B 1413 (step 1417). Here, the UE ID may be an ID specific to the D2D communication, or may be another UE ID. In an embodiment of the present invention, the UE ID may be an ID allocated to the UE # A 1411 for ProSe communication, for example, a ProSe UE ID. In another embodiment of the present invention, the UE ID may be the idle mode ID assigned to the UE #A 1411, e.g., S-TMSI. In another embodiment of the present invention, the UE ID may be a GUTI assigned to the UE #A 1411. [ When receiving the direct communication request message from the UE #A 1411, the UE #B 1413 receives the direct communication request message from the UE #A 1411, ID 1411 to the UE #A 1411 (step 1419).

The UE #A 1411 and the UE #B 1413 then send a direct communication request message to the eNB 1415 (steps 1421 and 1423). The UE #A 1411 and the UE #B 1413 are associated with the same eNB, eNB 1415. The UE #A 1411 and the UE #B 1413 each include their UE ID in the direct communication request message. It should be noted that there is no limitation on the order in which the UE #A 1411 and the UE #B 1413 transmit the direct communication request message to the eNB 1415. [

Upon receiving the direct communication request message from the UE #A 1411, the eNB 1415 authenticates the direct communication request message and assigns Tx-Idx and Rx-Idx to the UE #A 1411 do. The eNB 1415 directly transmits the Tx-Idx and the Rx-Idx allocated to the UE # A 1411 to the UE #A 1411 in step 1425. Also, the eNB 1415 includes the C-RNTI of the UE # A 1411 in the direct communication response message. In an embodiment of the present invention, the C-RNTI of the UE #A 1411 may be included in the direct communication response message when the C-RNTI is newly allocated to the UE #A 1411. If the C-RNTI is not allocated to the UE #A 1411, the eNB 1415 allocates the C-RNTI to the UE #A 1411. [ The eNB 1415 may include other parameters related to direct communication in the direct communication response message.

In addition, when receiving the direct communication request message from the UE #B 1413, the eNB 1415 authenticates the direct communication request message and informs the UE #B 1413 of Tx-Idx and Rx-Idx . The eNB 1415 includes Tx-Idx and Rx-Idx allocated to the UE #B 1413 in the direct communication response message, which is a response message to the direct communication request message, and transmits the direct communication response message to the UE #B 1413 (Step 1427). Also, the eNB 1415 includes the C-RNTI of the UE #B 1413 in the direct communication response message. In an embodiment of the present invention, the C-RNTI of the UE #B 1413 may be included in the direct communication response message when the C-RNTI is newly allocated to the UE #B 1413. If the C-RNTI is not allocated to the UE #B 1413, the eNB 1415 allocates the C-RNTI to the UE #B 1413. When receiving the direct communication response message from the eNB 1415, the UE #A 1411 and the UE #B 1413 respectively transmit a communication completion message directly to the eNB 1415 (steps 1429, 1431) step). Then, the UE #A 1411 and the UE #B 1413 start to use the allocated Tx-Idx and Rx-Idx. Since the C-RNTI, Tx-Idx, and Rx-Idx have been described above, detailed description thereof will be omitted here.

Meanwhile, in another embodiment of the present invention, the Tx-Idx and Rx-Idx are maintained by the UE itself. The UE allocates Tx-Idx and Rx-Idx for connection between another UE and the UE, and transmits the allocated Tx-Idx and Rx-Idx to the eNB during the direct connection establishment process. The eNB uses the Tx-Idx and Rx-Idx to store the Tx-Idx and Rx-Idx and transmit the PDCCH signal to the UE. The Tx-Idx and Rx-Idx may be transmitted by the UE to the eNB in the form of a direct communication request message for a direct communication complete message. Here, it should be noted that the characteristics of Tx-Idx and Rx-Idx are the same regardless of whether the Tx-Idx and Rx-Idx are allocated by the eNB or the UE.

For example, when the eNB allocates the Tx-Idx and the Rx-Idx, the eNB must maintain information on Tx-Idx and Rx-Idx already allocated to the connections of the UE, the eNB must keep information on Tx-Idx and Rx-Idx already allocated for all UEs.

As another example, when the UE allocates the Tx-Idx and Rx-Idx, the UE must maintain information on Tx-Idx and Rx-Idx that are already allocated to the connection of the UE, The load of the eNB is reduced.

14 shows another example of the intra-cell direct connection establishment and the Tx-Idx / Rx-Idx allocation process in the communication system supporting the D2D scheme according to the embodiment of the present invention, Of course. In one example, although the sequential steps are shown in FIG. 14, it is understood that the steps described in FIG. 14 may overlap, occur in parallel, occur in different orders, or occur multiple times.

In the above description, a first scheme for identifying a transmitter and a receiver when a transmission resource and a reception resource are allocated to a UE in a communication system supporting the D2D scheme according to an embodiment of the present invention has been described. A second scheme for identifying a transmitter and a receiver when a transmission resource and a reception resource are allocated to a UE in a communication system supporting the D2D scheme will now be described.

First, a connection index (connection_index: connection_idx) is allocated to each UE at the time when a direct connection is established. Here, the connection_idx is unique in a plurality of connections of other UEs and UEs. That is, the connection_idx is maintained independently for each UE. The connection_idx of the UE identifies which of the plurality of UEs is performing a receiving operation or a transmitting operation with the UE. As an example, UE # 1 is connected to UE # 2 and UE # 3. Connection_idx having a value of 0 is allocated to the UE # 1 for connection between the UE # 1 and the UE # 2 (connection_idx = 0). Also, a connection_idx having a value of 1 is allocated to the UE # 1 for connection between the UE # 1 and the UE # 3 (connection_idx = 1).

(1) a method of identifying the transmitter when the UE is allocated a receiving resource

Each UE may be connected to a plurality of UEs. When the UE is allocated transmission resources, the UE needs to determine which UE and the allocated transmission resources should be used to perform a transmission operation. A method for determining to which UE a UE should perform a transmission operation using transmission resources allocated to the UE itself according to an embodiment of the present invention will be described in detail as follows.

First, when the UE receives a control channel signal, for example, a PDCCH signal using the C-RNTI of the UE, and the Tx_Rx_indicator is set to 0, the UE transmits resource allocation information included in the control channel signal And will perform the receive operation on the corresponding resources.

Connection_idx in the control channel is used to identify the transmitter.

As an example, it is assumed that UE # 1 is connected to UE # 2 and UE # 3. Connection_idx having a value of 0 is assigned to the UE # 1 for connection between the UE # 1 and the UE # 2 (connection_idx = 0). Also, a connection_idx having a value of 1 is assigned to the UE # 1 (connection_idx = 1) for the connection between the UE # 1 and the UE # 3. When the UE # 1 receives the control channel signal using the C-RNTI of the UE # 1, the Tx_Rx_indicator is set to 0, and the connection_idx is set to 1, the UE # And perform the receiving operation in the resources corresponding to the resource allocation information included in the resource allocation information.

The connection_idx may be included as an information field in the control channel, or may be included in a CRC mask.

(2) when a transmission resource is allocated to the UE,

Each UE may be connected to a plurality of UEs. When the UE is allocated the reception resources for reception, the UE needs to determine which UE and the allocated reception resources should be used to perform the reception operation. A method for determining to which UE a UE should perform a receiving operation using received resources allocated to the UE in an embodiment of the present invention will be described in detail as follows.

First, when the UE receives a control channel signal using the C-RNTI of the UE, and the Tx_Rx_indicator is set to 1, the UE transmits the control channel signal in the resources corresponding to the resource allocation information included in the control channel signal Operation.

In the control channel signal, connection_idx is used to identify a UE to which the UE should perform a transmission operation.

As an example, it is assumed that UE # 1 is connected to UE # 2 and UE # 3. Connection_idx having a value of 0 is assigned to the UE # 1 for connection between the UE # 1 and the UE # 2 (connection_idx = 0). Also, connection_idx having a value of 1 is allocated to the UE # 1 (connection_idx = 1) for the connection between the UE # 1 and the UE # 3. When the UE # 1 receives the control channel signal using the C-RNTI of the UE # 1, the Tx_Rx_indicator is set to 1, and the connection_idx is set to 1, the UE # 1 transmits to the UE # 3 And perform transmission operations on resources corresponding to the resource allocation information included in the control channel signal.

Meanwhile, in another embodiment of the present invention, the connection_idx is maintained by the UE itself. The UE allocates a connection_idx for connection between another UE and the UE, and transmits the allocated connection_idx to the eNB during the direct connection establishment process. The eNB stores the connection_idx and uses the connection_idx to transmit a PDCCH signal to the UE. The connection_idx may be transmitted by the UE to the eNB in the form of a direct communication request message for a direct communication complete message. Here, it should be noted that the characteristics of the connection_idx are the same regardless of whether the connection_idx is allocated by the eNB or the UE.

For example, when the eNB allocates the connection_idx, the eNB must maintain information on connection_idx already allocated to the connections of the UE, and the eNB may allocate the connection_idx You should keep information about.

As another example, when the UE allocates the connection_idx, the UE must maintain information on connection_idxs already allocated to the connection of the UE, thereby reducing the load on the eNB.

 Hereinafter, with reference to FIG. 15 and FIG. 16, a process of transmitting resource allocation information to UEs included in a UE pair for inter-cell direct communication in a communication system supporting the D2D scheme according to an embodiment of the present invention Will be described.

15, another example of a process of transmitting resource allocation information to UEs included in a UE pair for inter-cell direct communication in a communication system supporting the D2D scheme according to an embodiment of the present invention Will be described.

15 is a diagram schematically showing another example of a process of transmitting resource allocation information to UEs included in a UE pair for inter-cell direct communication in a communication system supporting the D2D scheme according to an embodiment of the present invention. Fig.

15, the communication system includes a UE #A 1511, an eNB # 1 1513, an eNB # 2 1515, and a UE #B 1517.

The operations of steps 1519 to 1535 shown in FIG. 15 are the same as those of steps 619 to 635 described in FIG. 6 except that connection_idx is used instead of Tx-Idx and Rx-Idx.

Meanwhile, FIG. 15 shows another example of a process of transmitting resource allocation information to UEs included in a UE pair for intercell direct communication in a communication system supporting the D2D scheme according to an embodiment of the present invention It should be understood that various modifications may be made with respect to FIG. As an example, although successive steps are shown in FIG. 15, it is understood that the steps described in FIG. 15 may overlap, occur in parallel, occur in different orders, or occur multiple times.

15, another example of a process of transmitting resource allocation information to UEs included in a UE pair for intercell direct communication in a communication system supporting the D2D scheme according to an embodiment of the present invention has been described, 16, another example of a procedure for transmitting resource allocation information to UEs included in a UE pair for direct cell-to-cell communication in a communication system supporting the D2D scheme according to an embodiment of the present invention Will be described.

16 is a diagram schematically illustrating another example of a procedure for transmitting resource allocation information to UEs included in a UE pair for inter-cell direct communication in a communication system supporting the D2D scheme according to an embodiment of the present invention. Fig.

16, the communication system includes a UE # A 1611, an eNB # 1 1613, an eNB # 2 1615, and a UE #B 1617.

The operations of steps 1619 to 1635 shown in FIG. 16 are the same as those of steps 719 to 735 described in FIG. 7 except that connection_idx is used instead of Tx-Idx and Rx-Idx.

16 shows another example of a process of transmitting resource allocation information to UEs included in a UE pair for direct cell-to-cell communication in a communication system supporting the D2D scheme according to an embodiment of the present invention Needless to say, various modifications can be made to Fig. As an example, although successive steps are shown in FIG. 16, it is understood that the steps described in FIG. 16 may overlap, occur in parallel, occur in different orders, or occur multiple times.

Meanwhile, in one embodiment of the present invention, connection_idx may be allocated for each UE pair instead of each UE. In this case, connection_idx can be allocated by the MME.

In the above description, a second scheme for identifying a transmitter and a receiver when a transmission resource and a reception resource are allocated to a UE in a communication system supporting the D2D scheme according to an embodiment of the present invention has been described. A handover method in a communication system supporting the D2D scheme according to an example will be described as follows.

First, UEs communicating with each other using D2D communication may be mobile. Due to mobility, the UEs will handover from an enhanced Node B (eNB) to another eNB. As a result, during the direct communication between the UEs, the association between the eNB and the UE is continuously changed. Thus, some of the possible scenarios are:

(1) Scenario # 1

UE # A and UE # B are associated with eNB # 1 before handover. After handover, the UE # A is associated with the eNB # 1, and the UE # B is associated with the eNB # 2.

(2) Scenario # 2

UE # A and UE # B are associated with eNB # 1 before handover. After handover, the UE # A is associated with eNB # 3, and the UE # B is associated with eNB # 2.

(3) Scenario # 3

UE # A and UE # B are associated with eNB # 1 before handover. After handover, the UE #A and UE #B are associated with eNB # 2.

(4) Scenario # 4

UE # A and UE # B are associated with eNB # 1 and eNB # 2 before handover, respectively. After handover, the UE #A and the UE #B are associated with the eNB # 1.

(5) Scenario # 5

UE # A and UE # B are associated with eNB # 1 and eNB # 2 before handover, respectively. After handover, the UEs #A and #B are associated with the eNB # 3.

(6) Scenario # 6

UE # A and UE # B are associated with eNB # 1 and eNB # 2 before handover, respectively. After handover, the UE # A and the UE # B are associated with the eNB # 1 and the eNB # 3, respectively.

(7) Scenario # 7

UE # A and UE # B are associated with eNB # 1 and eNB # 2 before handover, respectively. After handover, the UEs #A and #B are associated with eNB # 3 and eNB # 4, respectively.

Hereinafter, with reference to FIG. 17, a description will be made of a handover process in a case where a UE performs a handover from an eNB to another eNB during a direct communication with another UE in a communication system supporting the D2D scheme according to an embodiment of the present invention. Respectively.

17 is a diagram schematically illustrating a handover process when a UE performs handover from one eNB to another eNB during direct communication with another UE in a communication system supporting the D2D scheme according to an embodiment of the present invention.

17, the communication system includes a UE # A 1711, an eNB # 1 1713, an eNB # 2 1715, and an MME 1717.

First, the UE # A 1711 transmits a measurement report message to the eNB # 1 1713 (step 1719). Upon receiving the measurement report message from the UE #A 1711, the eNB # 1 1713 determines that handover is required to the UE #A 1711 based on the measurement report message in step 1721, and transmits a direct connection handover request message to the eNB # 2 1715 (step 1723). Here, the direct connection handover request message includes information on each of the direct connections of the UE # A 1711. [ Here, the information on the direct connection includes, for example, a UE ID of a UE connected to the UE #A 1711 and connection parameters for identifying connection between the UEs and the UE #A 1711 .

The eNB # 2 1715 that has received the direct connection handover request message from the eNB # 1 1713 performs an admission control operation with respect to the UE #A 1711 in step 1725, The UE 1711 determines the eNB / cell of each of the directly communicating UEs in step 1727, and transmits a UE cell information request message to the MME 1717 if the eNB / (Step 1729). Herein, the UE cell information request message includes UE IDs of UEs in which the UE #A 1711 is directly communicating. Upon receiving the UE cell information request message from the eNB # 2 1715, the MME 1717 transmits a UE cell information response, which is a response message to the eNB # 2 1715, Message (step 1731). Herein, the UE cell information response message includes information on eNBs / cells of UEs in which UE # A 1711 is directly communicating.

Also, the MME 1717 may update the eNB # 2 1715 when the UE cell information is changed (step 1733). Here, the step 1733 may be performed selectively. The eNB # 2 1715 transmits the updated eNB 1711 to the MME 1717 when the UE A 1711 handover to another eNB or when the connection between the UE A 1711 and another UE ends, / Cell cell information is not transmitted.

After the UE #A 1711 determines eNB / cell information of each UE directly communicating, the eNB # 2 1715 transmits a direct connection handover request ACK (acknowledgment) to the eNB # 1 1713, Message (step 1735). Here, the direct connection handover request ACK message includes the C-RNTI of the UE #A 1711 and other direct connection parameters. The eNB # 1 1713 having received the direct connection handover request ACK message from the eNB # 2 1715 transmits a direct connection reconfiguration message including the C-RNTI of the UE #A 1711 and other direct connection parameters, reconfiguration message to the UE # A 1711 (step 1737). Also, the eNB # 1 1713 that has transmitted the direct connection reconfiguration message releases the logical connection with other eNBs for the direct connection between the UEs and the UE # A 1711 (1739 step).

Meanwhile, the UE # A 1711 receiving the direct connection reconfiguration message from the eNB # 1 1713 transmits the direct connection reconfiguration completion message to the eNB # 2 1715 in step 1741. Herein, the direct connection reconfiguration completion message includes the C-RNTI of the UE #A 1711. [ The eNB # 2 1715 receiving the direct connection reconfiguration completion message establishes a logical connection with the eNB (s) of the UE (s) to which the UE #A 1711 is communicating (step 1743). Here, it should be noted that step 1743 is performed when the eNB (s) of the UE (s) to which the UE #A 1711 is collectively communicating is not the eNB # 2 (1715). For example, the UE #A 1711 is in direct communication with the UE #C associated with the eNB # 3. Therefore, the UE # A 1711 handover to the eNB # 2 1715, and the eNB # 2 1715 establishes a connection with the eNB # 3 1715. The eNB # 2 1715 also has a logical connection with the other eNB and the eNB # 2 1715 for the UE (s) associated with the eNB # 2 1715 and directly communicating with the UE # (Step 1745). For example, the UE #B belongs to the eNB # 2 1715 and is in direct communication with the UE # A 1711 associated with the eNB # 1 1713. The UE # A 1711 handover to the eNB # 2 1715 and the eNB # 2 1715 transmits the logical connection with the eNB # 1 1713 to the UE #A-UE # Release.

Meanwhile, although FIG. 17 illustrates a handover process in a case where a UE performs a handover from an eNB to another eNB during a direct communication with another UE in a communication system supporting the D2D scheme according to an embodiment of the present invention, It goes without saying that this can be done with respect to FIG. As an example, although the successive steps are shown in FIG. 17, it is understood that the steps described in FIG. 17 may overlap, occur in parallel, occur in different orders, or occur multiple times.

Meanwhile, in an embodiment of the present invention, the source eNB may transmit a direct handover request message to the target eNB through the MME.

In one embodiment of the present invention, information on the eNB / Cell information of the eNB (s) of the UE (s) directly communicated by the UE # A is transmitted to the eNB # 2 by the eNB # 1 through a direct connection handover request message Lt; / RTI >

Hereinafter, a handover process in scenario # 1 in a communication system supporting the D2D scheme according to an embodiment of the present invention will be described with reference to FIGS. 18A to 18B.

18A to 18B are signal flow diagrams schematically illustrating a handover process in scenario # 1 in a communication system supporting the D2D scheme according to an embodiment of the present invention.

18A to 18B, the communication system includes a UE # A 1811, a UE # B 1813, an eNB # 1 1815, an eNB # 2 1817, and an MME 1819 do.

First, UE # A 1811 and UE # B 1813 are associated with eNB # 1 1815 before handover. The UE #A 1811 and the UE B 1813 directly communicate with each other and the eNB # 1 1815 sends a resource request to the UE #A 1811 and the UE #B 1813 (Step 1821).

The UE #B 1813 transmits a measurement report message to the eNB # 1 1815 (step 1823). Upon receiving the measurement report message from the UE #B 1813, the eNB # 1 1815 determines that handover is required to the UE #B 1813 based on the measurement report message (step 1825) and transmits a direct connection handover request message to the eNB # 2 1817 (step 1827). Herein, the direct connection handover request message may include a UE ID of the UE #A 1811 and connection parameters for identifying a connection between the UE #A 1811 and the UE #B 1813, have.

The eNB # 2 1817 that has received the direct connection handover request message from the eNB # 1 1815 performs an admission control operation with respect to the UE B 1813 in step 1831, (1833) determines the eNB / cell of the UE #A (1811) that is directly communicating with the UE # A (1811). If the eNB / cell information is not available, the eNB # 2 1817 transmits a UE cell information request message to the MME 1819 (step 1835). Herein, the UE cell information request message includes the UE ID of the UE #A 1811. Upon receiving the UE cell information request message from the eNB # 2 1817, the MME 1819 transmits a UE cell information response message as a response to the UE cell information request message to the eNB # 2 1817 step). Herein, the UE cell information response message includes eNB / cell information of the UE #A 1811, that is, information about the eNB # 1 1815. Also, the MME 1819 may update the eNB # 2 1817 when the UE cell information for the UE #A 1811 is changed (Step 1839). Here, the step 1839 may be selectively performed. In addition, the eNB # 2 1817 notifies the MME 1819 when the UE #B 1813 handover to another eNB or when the connection between the UE #B 18131 and the UE #A 1811 is terminated. And notify that the updated eNB / cell information is not to be transmitted.

After determining the eNB / cell information of the UE #A 1811 directly communicating with the UE #B 1813, the eNB # 2 1817 transmits a direct connection handover request to the eNB # 1 1815 ACK message (Step 1841). Herein, the direct connection handover request ACK message includes the C-RNTI of the UE #B 1813 and other direct connection parameters. The eNB # 1 1815 receiving the direct connection handover request ACK message from the eNB # 2 1817 transmits a direct connection reconfiguration message including the C-RNTI of the UE #B 1813 and other direct connection parameters. reconfiguration message to the UE #B 1813 (Step 1843).

The UE # B 1813 having received the direct connection reconfiguration message from the eNB # 1 1815 transmits the direct connection reconfiguration completion message to the eNB # 2 1817 in step 1845. Herein, the direct connection reconfiguration completion message includes the C-RNTI of the UE #B 1813. Upon receiving the direct connection reconfiguration completion message, the eNB # 2 1817 establishes a logical connection with the eNB # 1 1815 (step 1847). Then, a logical connection establishing process is performed between the eNB # 1 1815 and the eNB # 2 1817 to adjust resources for direct communication between the UE #A 1811 and the UE #B 1813 ). Also, resource adjustment is performed between the eNB # 1 1815 and the eNB # 2 1817 (step 1851). Accordingly, the eNB # 1 1815 transmits information on the determined resources to the UE #A 1811 (step 1853). Also, the eNB # 2 1817 transmits information on the determined resources to the UE #B 1813 (step 1855). Here, the eNB # 2 1817 uses the same connection identifiers that identify the connection between the UE #A 1811 and the UE #B 1813, and uses a new C-RNTI to allocate resources.

18A to 18B illustrate a handover process in scenario # 1 in a communication system supporting the D2D scheme according to an embodiment of the present invention, various modifications may be made to FIGS. 18A to 18B Of course. 18A-18B, the steps described in FIGS. 18A-18B may overlap, occur in parallel, may occur in a different order, or may occur multiple times Of course.

18A to 18B, a handover process in scenario # 1 in a communication system supporting the D2D scheme according to an embodiment of the present invention has been described. Next, referring to FIGS. 19A to 19B, The handover process in scenario # 2 in the communication system supporting the D2D scheme according to the example will be described.

19A and 19B are signal flow diagrams schematically illustrating a handover process in scenario # 2 in a communication system supporting the D2D scheme according to an embodiment of the present invention.

19A-19B, the communication system includes a UE # A 1911, a UE # B 1913, an eNB # 1 1915, an eNB # 2 1917, an eNB # And an MME 1921.

First, UE # A 1911 and UE # B 1913 are associated with eNB # 1 1915 before handover. The UE #A 1911 and the UE B 1913 directly communicate with each other and the eNB # 1 1915 transmits resources to the UE #A 1911 and the UE #B 1913 (Step 1923). The UE # B 1913 handover from the eNB # 1 1915 to the eNB # 2 1917 using the process described in the scenario # 1 (step 1925).

The UE #A 1911 transmits a measurement report message to the eNB # 1 1915 (step 1927). Upon receiving the measurement report message from the UE #A 1911, the eNB # 1 1915 determines that handover is required to the UE #A 1911 based on the measurement report message in step 1929, and transmits a direct connection handover request message to the eNB # 3 1919 (step 1931). Herein, the direct connection handover request message may include a UE ID of the UE #B 1913 and connection parameters for identifying a connection between the UE #A 1911 and the UE #B 1913 have.

The eNB # 3 1919 that has received the direct connection handover request message from the eNB # 1 1915 performs an admission control operation for the UE #A 1911 in step 1933 and the UE # (1935) determines the eNB / cell of the UE #B (1913) in direct communication. If the eNB / cell information is not available, the eNB # 3 1919 transmits a UE cell information request message to the MME 1921 (step 1937). Herein, the UE cell information request message includes the UE ID of the UE #B 1913. Upon receiving the UE cell information request message from the eNB # 3 1919, the MME 1921 transmits a UE cell information response message as a response to the UE cell information request message to the eNB # 3 1919 step).

Here, the UE cell information response message includes eNB / cell information of the UE #B 1913, that is, information on the eNB # 2 1917. Also, the MME 1921 may update the eNB # 3 1919 when the UE cell information for the UE #B 1913 is changed (Step 1941). Here, the step 1941 may be selectively performed. The eNB # 3 1919 also informs the MME 1921 when the UE #A 1911 handover to another eNB or when the connection between the UE #A 1911 and the UE #B 1913 is terminated. And notify that the updated eNB / cell information is not to be transmitted.

After determining the eNB / cell information of the UE #B 1913 directly communicating with the UE #A 1911, the eNB # 3 1919 transmits a direct connection handover request ACK Message (Step 1943). Here, the direct connection handover request ACK message includes the C-RNTI of the UE #A 1911 and other direct connection parameters. The eNB # 1 1915 which has received the direct connection handover request ACK message from the eNB # 3 1919 transmits a direct connection reconfiguration message including the C-RNTI of the UE #A 1911 and other direct connection parameters to the eNB # To the UE # A 1911 (Step 1945). Also, the eNB # 1 1915 releases the logical connection with the eNB # 2 1917 (step 1947).

Meanwhile, the UE # A 1911 receiving the direct connection reconfiguration message from the eNB # 1 1915 transmits a direct connection reconfiguration completion message to the eNB # 3 1919 in step 1949. Herein, the direct connection reconfiguration completion message includes the C-RNTI of the UE #A 1911. The eNB # 3 (1919) having received the direct connection reconfiguration completion message from the UE #A (1911) establishes a logical connection with the eNB # 2 (1917) (Step 1951). Then, a logical connection establishing process is performed between the eNB # 2 1917 and the eNB # 3 1919 to adjust resources for direct communication between the UE #A 1911 and the UE #B 1913 (Step 1953 ). Also, the eNB # 2 1917 releases the logical connection with the eNB # 1 1915 (step 1955).

Also, resource adjustment is performed between the eNB # 2 (1917) and the eNB # 3 (1919) (Step 1957). Accordingly, the eNB # 2 1917 transmits information on the determined resources to the UE #B 1913 (Step 1959). Here, the eNB # 2 1917 uses the same connection identifiers that identify the connection between the UE #A 1911 and the UE #B 1913, and uses a new C-RNTI to allocate resources. Also, the eNB # 3 1919 transmits information on the determined resources to the UE #A 1911 (step 1961). Here, the eNB # 3 1919 uses the same connection identifiers that identify the connection between the UE #A 1911 and the UE #B 1913, and uses a new C-RNTI to allocate resources.

19A and 19B illustrate a handover process in scenario # 2 in a communication system supporting the D2D scheme according to an embodiment of the present invention, various modifications can be made to 19a-19b to be. For example, while the successive steps are shown in FIGS. 19A-19B, the steps described in FIGS. 19A-19B may overlap, occur in parallel, occur in different orders, Of course.

19A and 19B, a handover process in a scenario # 2 in a communication system supporting the D2D scheme according to an embodiment of the present invention is described. Next, referring to FIG. 20, a D2D The handover process in the scenario # 3 in the communication system supporting the scheme will be described.

20 is a signal flow diagram schematically illustrating a handover process in scenario # 3 in a communication system supporting the D2D scheme according to an embodiment of the present invention.

20, the communication system includes a UE # A (2011), a UE # B 2013, an eNB # 1 2015, and an eNB # 2 2017.

First, UE # A (2011) and UE # B (2013) are associated with eNB # 1 (2015) before handover. The eNB # 1 2015 communicates resources to the UEs #A 2011 and # 2013, and the UE # A 2013 directly communicates with the UE # (Step 2019). The UE # B 2013 handover from the eNB # 1 2015 to the eNB # 2 2017 using the process described in scenario # 1 (step 2021).

The UE # A (2011) transmits a measurement report message to the eNB # 1 (2015) (step 2023). Upon receiving the measurement report message from the UE #A 2011, the eNB # 1 2015 determines that handover is required to the UE # A 2011 based on the measurement report message in step 2025, and transmits a direct connection handover request message to the eNB # 2 2017 (step 2027). Herein, the direct connection handover request message may include a UE ID of the UE #B 2013, connection parameters for identifying a connection between the UE #A 2011 and the UE #B 2013, have.

The eNB # 2 2017 that has received the direct connection handover request message from the eNB # 1 2015 performs an admission control operation for the UE #A 2011 in step 2029 and the UE # (ENB / cell) of the UE # B 2013 directly communicating with the UE # B 2013 (Step 731). Since the UE #B 2013 exists together with the eNB # 2 2017, it is not required to request eNB / cell information from the MME. The eNB # 2 2017 transmits a direct handover ACK message to the eNB # 1 2015 in step 2033. Herein, the direct communication handover ACK message includes the C-RNTI of the UE #A 2011 and other direct communication parameters.

Upon receiving the direct handover ACK message from the eNB # 2 2017, the eNB # 1 2015 transmits a direct connection reconfiguration message to the UE # A 2013 in step 2035. The direct connection reconfiguration message includes the C-RNTI and other direct communication parameters of the UE # A (2011). Also, the eNB # 1 (2015) releases the logical connection with the eNB # 2 (2017) (step 2037).

On the other hand, the UE #A 2011 receiving the direct connection reconfiguration message from the eNB # 1 2015 transmits a direct connection reconfiguration completion message, which is a response message to the direct connection reconfiguration message, to the eNB # 2 2017 (Step 2039). Here, the direct connection reconfiguration completion message includes the C-RNTI of the UE # A (2011). The eNB # 2 2017 that has received the direct connection reconfiguration completion message from the UE #A 2011 releases the logical connection with the eNB # 1 2015 in step 2041 and transmits the connection reconfiguration completion message to the UE # And transmits information on resources for #B 2013 (Step 2043).

Although FIG. 20 illustrates a handover process in scenario # 3 in the communication system supporting the D2D scheme according to an embodiment of the present invention, various modifications may be made to FIG. As an example, although successive steps are shown in FIG. 20, it is understood that the steps described in FIG. 20 may overlap, occur in parallel, occur in different orders, or occur multiple times.

20 illustrates a handover process in scenario # 3 in a communication system supporting the D2D scheme according to an embodiment of the present invention. Referring to FIG. 21, a D2D scheme according to an embodiment of the present invention The handover process in the scenario # 4 in the supporting communication system will be described.

21 is a signal flow diagram schematically illustrating a handover process in scenario # 4 in a communication system supporting the D2D scheme according to an embodiment of the present invention.

Referring to FIG. 21, the communication system includes a UE # A 2111, a UE # B 2113, an eNB # 1 2115, and an eNB # 2 2117.

First, UE # A 2111 and UE # B 2113 are associated with eNB # 1 2115 before handover. Then, the UE #A 2111 and the UE #B 2113 directly communicate with each other (Step 2119). The UE #A 2111 transmits a measurement report message to the eNB # 1 2115 (step 2121). Upon receiving the measurement report message from the UE #A 2111, the eNB # 1 2115 determines that handover is required to the UE #A 2111 based on the measurement report message in step 2123, and transmits a direct connection handover request message to the eNB # 2 2117 (step 2125). Herein, the direct connection handover request message may include a UE ID of the UE #B 2113 and connection parameters for identifying a connection between the UE #A 2111 and the UE #B 2113, have.

The eNB # 2 2117 that has received the direct connection handover request message from the eNB # 1 2115 performs an admission control operation with respect to the UE A 2111 in step 2127, (ENB / cell) of each of the UEs directly communicating with each other (step 2129). The eNB # 2 2117 directly transmits a communication handover ACK message to the eNB # 1 2115 (step 2131). Here, the direct communication handover ACK message includes the C-RNTI of the UE #A 2111 and other direct communication parameters.

The eNB # 1 2115 that has received the direct communication handover ACK message from the eNB # 2 2117 transmits the direct connection reconfiguration message to the UE #A 2111 in step 2133. The direct connection reconfiguration message includes the C-RNTI of UE # A 2111 and other direct communication parameters. Also, the eNB # 1 2115 releases the logical connection with the eNB # 2 2117 (step 2135).

On the other hand, the UE # A 2111 receiving the direct connection reconfiguration message from the eNB # 1 2115 transmits a direct connection reconfiguration completion message, which is a response message to the direct connection reconfiguration message, to the eNB # 2 2117 (Step 2137). Herein, the direct connection reconfiguration completion message includes the C-RNTI of the UE #A 2111. The eNB # 2 2117 that has received the direct connection reconfiguration completion message from the UE #A 2111 releases the logical connection with the eNB # 1 2115 in step 2139 and the UE # And transmits information on resources for the #B 2113 (step 2141).

Meanwhile, although FIG. 21 shows a handover process in scenario # 4 in a communication system supporting the D2D scheme according to an embodiment of the present invention, various modifications may be made to FIG. As an example, although the sequential steps are shown in FIG. 21, it is understood that the steps described in FIG. 21 may overlap, occur in parallel, occur in different orders, or occur multiple times.

FIG. 21 illustrates a handover process in scenario # 4 in a communication system supporting the D2D scheme according to an embodiment of the present invention. Next, in a communication system supporting the D2D scheme according to an embodiment of the present invention, The handover process in Scenario # 5 to Scenario # 7 will be described below.

First, the handover process in scenario # 5 will be described as follows.

UE # A and UE # B are associated with eNB # 1 and eNB # 2 before handover, respectively. After handover, the UEs #A and #B are associated with the eNB # 3. In this case, the UE #A handover from the eNB # 1 to the eNB # 3 using the process defined in FIG. 17, and the UE # B handover from the eNB # 2 to the eNB # 3 .

Second, the handover process in scenario # 6 will be described as follows.

UE # A and UE # B are associated with eNB # 1 and eNB # 2 before handover, respectively. After handover, the UEs #A and #B are associated with eNB # 1 and eNB # 3, respectively. In this case, the UE #B performs handover from the eNB # 2 to the eNB # 3 using the process defined in FIG.

Third, the handover process for scenario # 7 will be described as follows.

UE # A and UE # B are associated with eNB # 1 and eNB # 2 before handover, respectively. After handover, the UEs #A and #B are associated with the eNB # 3 and the eNB # 4, respectively. In this case, UE # A handover from eNB # 1 to eNB # 3 using the process defined in FIG. 17, and UE # B handover from eNB # 2 to eNB # 4.

22, the internal structure of a UE in a communication system supporting the D2D scheme according to an embodiment of the present invention will be described.

22 is a diagram schematically illustrating an internal structure of a UE in a communication system supporting the D2D scheme according to an embodiment of the present invention.

22, the UE 2200 includes a transmitter 2211, a controller 2213, a receiver 2215, and a storage unit 2217.

First, the controller 2213 controls the overall operation of the UE 2200. The controller 2213 controls the UE 2200 to perform an overall operation related to a resource allocation and a handover operation according to an embodiment of the present invention. Here, operations for performing the resource allocation and handover operation according to the embodiment of the present invention are the same as those described with reference to FIG. 6 to FIG. 21, and detailed description thereof will be omitted here.

Under the control of the controller 2213, the transmitter 2211 transmits various signals and various messages to another UE, an eNB, and the like. Here, various signals and various messages transmitted by the transmitter 2211 are the same as those described with reference to FIG. 6 to FIG. 21, and a detailed description thereof will be omitted here.

In addition, the receiver 2215 receives various signals and various messages from the other UE, the eNB, and the like under the control of the controller 2213. Here, various signals and various messages received by the receiver 2215 are the same as those described with reference to FIGS. 6 to 21, and a detailed description thereof will be omitted here.

The storage unit 2217 stores programs and various data necessary for the operation of the UE 2200, and particularly information related to a resource allocation and a handover operation according to an embodiment of the present invention. The storage unit 2217 stores various signals and various messages received by the receiver 2215 from the other UE, the eNB, and the like.

22 shows a case where the UE 2200 is implemented as separate units such as the transmitter 2211, the controller 2213, the receiver 2215, and the storage unit 2217, It is needless to say that the UE 2200 can be implemented by integrating at least two of the transmitter 2211, the controller 2213, the receiver 2215 and the storage unit 2217 into one unit.

22 illustrates an internal structure of a UE in a communication system supporting the D2D scheme according to an embodiment of the present invention. Referring to FIG. 23, a communication system supporting the D2D scheme according to an embodiment of the present invention The internal structure of the eNB will be described.

23 is a diagram schematically illustrating an internal structure of an eNB in a communication system supporting the D2D scheme according to an embodiment of the present invention.

23, the eNB 2300 includes a transmitter 2311, a controller 2313, a receiver 2315, and a storage unit 2317.

First, the controller 2313 controls the overall operation of the eNB 2300. The controller 2313 controls the eNB 2300 to perform an overall operation related to the resource allocation and handover operation according to an embodiment of the present invention. Here, operations for performing the resource allocation and handover operation according to the embodiment of the present invention are the same as those described with reference to FIG. 6 to FIG. 21, and detailed description thereof will be omitted here.

The transmitter 2311 transmits various signals and various messages to the UE, another eNB, an MME, and the like under the control of the controller 2313. Here, various signals and various messages transmitted by the transmitter 2311 are the same as those described with reference to FIGS. 6 to 21, and a detailed description thereof will be omitted here.

In addition, the receiver 2315 receives various signals and various messages from the UE, another eNB, the MME, and the like under the control of the controller 2313. Various signals and various messages received by the receiver 2315 are the same as those described with reference to FIGS. 6 to 21, and a detailed description thereof will be omitted here.

The storage unit 2317 stores programs necessary for the operation of the eNB 2300, various data, and the like, in particular, information related to resource allocation and handover operation performing operations according to an embodiment of the present invention. The storage unit 2317 stores various signals and various messages received by the receiver 2315 from the UE, another eNB, an MME, and the like.

23 shows a case where the eNB 2300 is implemented as separate units such as the transmitter 2311, the controller 2313, the receiver 2315, and the storage unit 2317, It is needless to say that the eNB 2300 can be realized by integrating at least two of the transmitter 2311, the controller 2313, the receiver 2315 and the storage unit 2317 into one unit.

23 illustrates an internal structure of an eNB in a communication system supporting the D2D scheme according to an embodiment of the present invention. Referring to FIG. 24, a communication system supporting the D2D scheme according to an embodiment of the present invention The internal structure of the MME will be described.

24 is a diagram schematically illustrating an internal structure of an MME in a communication system supporting the D2D scheme according to an embodiment of the present invention.

24, the MME 2400 includes a transmitter 2411, a controller 2413, a receiver 2415, and a storage unit 2417.

First, the controller 2413 controls the overall operation of the MME 2400. The controller 2413 controls the MME 2400 to perform an overall operation related to the resource allocation and handover operation according to an embodiment of the present invention. Here, operations for performing the resource allocation and handover operation according to the embodiment of the present invention are the same as those described with reference to FIG. 6 to FIG. 21, and detailed description thereof will be omitted here.

The transmitter 2411 transmits various signals and various messages to the eNB according to the control of the controller 2413. Here, various signals and various messages transmitted by the transmitter 2411 are the same as those described with reference to FIGS. 6 to 21, and a detailed description thereof will be omitted here.

In addition, the receiver 2415 receives various signals and various messages from the eNB and the like under the control of the controller 2413. Here, various signals and various messages received by the receiver 2415 are the same as those described with reference to FIGS. 6 to 21, and a detailed description thereof will be omitted here.

The storage unit 2417 stores programs and various data necessary for the operation of the MME 2400, particularly information related to resource allocation and handover operation according to an embodiment of the present invention. The storage unit 2417 stores various signals and various messages received from the eNB and the like by the receiver 2415.

24 shows a case where the MME 2400 is implemented as separate units such as the transmitter 2411, the controller 2413, the receiver 2415, and the storage unit 2417, It is needless to say that the MME 2400 can be realized by integrating at least two of the transmitter 2411, the controller 2413, the receiver 2415 and the storage unit 2417 into one unit.

Certain aspects of the invention may also be implemented as computer readable code in a computer readable recording medium. The computer readable recording medium is any data storage device capable of storing data that can be read by a computer system. Examples of the computer-readable recording medium include a read only memory (ROM), a random access memory (RAM) And compact disk-read only memories (CD-ROMs), magnetic tapes, floppy disks, optical data storage devices, and carrier waves and carrier waves (such as data transmission over the Internet). The computer readable recording medium may also be distributed over networked computer systems, and thus the computer readable code is stored and executed in a distributed manner. Also, functional programs, code, and code segments for accomplishing the present invention may be readily interpreted by programmers skilled in the art to which the invention applies.

It will also be appreciated that the apparatus and method according to an embodiment of the present invention may be implemented in hardware, software, or a combination of hardware and software. Such arbitrary software may be stored in a memory such as, for example, a volatile or non-volatile storage device such as a storage device such as ROM or the like, or a memory such as a RAM, a memory chip, a device or an integrated circuit, , Or stored in a storage medium readable by a machine (e.g., a computer), such as a compact disk (CD), a DVD, a magnetic disk or a magnetic tape, have. The method according to an embodiment of the present invention can be implemented by a computer or a mobile terminal including a control unit and a memory and the memory is suitable for storing a program or programs including instructions embodying the embodiments of the present invention It is an example of a machine-readable storage medium.

Accordingly, the invention includes a program comprising code for implementing the apparatus or method as claimed in any of the claims herein, and a storage medium readable by a machine (such as a computer) for storing such a program. In addition, such a program may be electronically transferred through any medium, such as a communication signal carried over a wired or wireless connection, and the present invention appropriately includes equivalents thereof

Also, an apparatus according to an embodiment of the present invention may receive and store the program from a program providing apparatus connected by wire or wireless. The program providing apparatus includes a memory for storing a program including instructions for causing the program processing apparatus to perform a predetermined content protection method, information necessary for the content protection method, and the like, and a wired or wireless communication with the graphics processing apparatus And a control unit for transmitting the program to the transceiver upon request or automatically by the graphic processing apparatus.

While the present invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiments, but is capable of various modifications within the scope of the invention. Therefore, the scope of the present invention should not be limited by the described embodiments, but should be determined by the scope of the appended claims and equivalents thereof.

Claims (28)

A method of performing a handover by a user equipment (UE) in a communication system supporting a device to device (D2D) scheme,
And receiving a direct connection reconfiguration message from an enhanced node B (eNB)
Wherein the direct connection reconfiguration message includes information about each of the direct connections of the UE,
Wherein the information on each of the direct connections includes a UE identifier and connection parameters. ≪ Desc / Clms Page number 19 >
The method according to claim 1,
Wherein the connection parameters are used to identify connections between the UEs and other UEs in a communication system supporting a D2D scheme.
The method according to claim 1,
Further comprising the step of transmitting a measurement report message to the eNB before receiving the direct connection reconfiguration message from the eNB. ≪ Desc / Clms Page number 19 >
The method according to claim 1,
Further comprising the step of transmitting a direct connection reconfiguration completion message, which is a response message to the direct connection reconfiguration message, to another eNB to which the UE performs handover, in a communication system supporting the D2D scheme, Lt; / RTI >
The method according to claim 1,
Wherein the direct connection reconfiguration message is received when the eNB determines that the UE needs to perform a handover.
A method for supporting handover of an enhanced Node B (eNB) in a communication system supporting a device to device (D2D) scheme,
Comprising the steps of: determining that a user equipment (UE) needs to perform handover to another eNB;
And transmitting a direct connection handover request message to the other eNB,
Wherein the direct connection handover request message includes information on each of the direct connections of the UE,
Wherein the information about each of the direct connections includes an identifier (ID) and connection parameters. The method of claim 1, wherein the eNB supports handover in a communication system supporting the D2D scheme.
The method according to claim 6,
Wherein the connection parameters are used to identify connections between other UEs and the UE.
The method according to claim 6,
Further comprising receiving a measurement report message from the UE prior to transmitting the direct reconfiguration message to the UE. The method of claim 1, wherein the eNB supports handover in a communication system supporting a D2D scheme.
The method according to claim 6,
Further comprising the step of receiving a direct connection handover acknowledgment (ACK) message from the other eNB in a communication system supporting the D2D scheme.
10. The method of claim 9,
Further comprising the step of transmitting a direct connection reconfiguration message to the UE,
Wherein the direct connection reconfiguration message includes information about each of the direct connections of the UE,
Wherein the information on each of the direct connections includes the UE ID and the connection parameters, wherein the eNB supports handover in a communication system supporting the D2D scheme.
A method for supporting handover of an enhanced Node B (eNB) in a communication system supporting a device to device (D2D) scheme,
And receiving a direct connection handover request message from another eNB,
Wherein the direct connection handover request message includes information on each of the direct connections of the UE,
Wherein the information about each of the direct connections includes an identifier (ID) and connection parameters. The method of claim 1, wherein the eNB supports handover in a communication system supporting the D2D scheme.
12. The method of claim 11,
Wherein the connection parameters are used to identify connections between other UEs and the UE.
12. The method of claim 11,
Further comprising the step of transmitting a direct connection handover acknowledgment (ACK) message to the other eNB. The method of claim 1, wherein the eNB supports handover in a communication system supporting the D2D scheme.
12. The method of claim 11,
Further comprising the step of receiving a direct connection reconfiguration completion message, which is a response message to the direct connection reconfiguration message received from the other eNB, from the UE, wherein the eNB supports handover in a communication system supporting the D2D scheme Way.
In a user equipment (UE) in a communication system supporting a device to device (D2D) scheme,
And a receiver for receiving a direct connection reconfiguration message from an enhanced node B (eNB)
Wherein the direct connection reconfiguration message includes information about each of the direct connections of the UE,
Wherein the information about each of the direct connections includes a UE identifier and connection parameters.
16. The method of claim 15,
Wherein the connection parameters are used to identify a connection between the UE and other UEs in a communication system supporting the D2D scheme.
16. The method of claim 15,
Further comprising a transmitter for transmitting a measurement report message to the eNB before receiving the direct connection reconfiguration message from the eNB.
16. The method of claim 15,
Further comprising: a transmitter for transmitting a direct connection reconfiguration completion message, which is a response message to the direct connection reconfiguration message, to another eNB to which the UE performs handover, in a communication system supporting the D2D scheme.
16. The method of claim 15,
Wherein the direct connection reconfiguration message is received when the eNB determines that the UE needs to perform a handover.
In an enhanced Node B (eNB) in a communication system supporting a device to device (D2D) scheme,
A controller that determines that a user equipment (UE) needs to perform handover to another eNB;
And a transmitter for transmitting a direct connection handover request message to the other eNB,
Wherein the direct connection handover request message includes information on each of the direct connections of the UE,
Wherein the information on each of the direct connections includes a UE identifier and connection parameters.
21. The method of claim 20,
Wherein the connection parameters are used to identify connections between the UEs and other UEs in a communication system supporting the D2D scheme.
21. The method of claim 20,
Further comprising a receiver for receiving a measurement report message from the UE prior to transmitting the direct connection reconfiguration message to the UE.
21. The method of claim 20,
Further comprising a receiver for receiving a direct handover acknowledgment (ACK) message from the other eNB in the communication system supporting the D2D scheme.
24. The method of claim 23,
The transmitter transmits a direct connection reconfiguration message to the UE,
Wherein the direct connection reconfiguration message includes information about each of the direct connections of the UE,
Wherein the information on each of the direct connections includes the UE ID and the connection parameters.
In an enhanced Node B (eNB) in a communication system supporting a device to device (D2D) scheme,
And a receiver for receiving a direct connection handover request message from another eNB,
Wherein the direct connection handover request message includes information on each of the direct connections of the UE,
Wherein the information on each of the direct connections includes a UE identifier and connection parameters.
26. The method of claim 25,
Wherein the connection parameters are used to identify connections between the UEs and other UEs in a communication system supporting the D2D scheme.
26. The method of claim 25,
Further comprising a transmitter for transmitting a direct connection handover acknowledgment (ACK) message to the other eNB in the communication system supporting the D2D scheme.
26. The method of claim 25,
Wherein the receiver receives a direct connection reconfiguration completion message, which is a response message to the direct connection reconfiguration message received from the other eNB, from the UE.

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