KR20140129970A

KR20140129970A - dual mode user equipment in HetNets, and method and system using the same

Info

Publication number: KR20140129970A
Application number: KR1020130048969A
Authority: KR
Inventors: 이태진; 조우종; 오창영
Original assignee: 인텔렉추얼디스커버리 주식회사
Priority date: 2013-04-30
Filing date: 2013-04-30
Publication date: 2014-11-07

Abstract

Various embodiments of a dual mode terminal in a heterogeneous network, a method and a system using the same are disclosed. According to an embodiment of the present invention, an operation method of a dual mode terminal can comprise the steps of: connecting, by a first dual mode terminal - link connected to a first base station - to one or more second dual mode terminals - link connected to a second base station - through each D2D(Device-to-Device) link; receiving, by the first dual mode terminal, a relay request frame from the one or more second dual mode terminals through the each D2D link; and setting, by the first dual mode terminal, a relay so that the first base station can communicate with a relay object terminal - one among the one or more second dual mode terminals.

Description

TECHNICAL FIELD [0001] The present invention relates to a dual mode terminal in a heterogeneous network, and a method and system for using the dual mode terminal in a heterogeneous network.

The disclosed technique relates to a dual mode terminal in a heterogeneous network, a method and system for using the same.

Mobile data traffic is increasing rapidly in Cellular Networks due to the increase in penetration rate of smartphones and tablet PCs, which is causing serious problems of network load increase. As a method for reducing the network load, the 3rd Generation Partnership Project (3GPP) has proposed a heterogeneous system in which a service area of a small cell such as a femtocell or a picocell is superimposed on an existing macro cell area, Network (Heterogeneous Networks, HetNets).

A dual mode terminal that supports not only a cellular based communication method but also other communication methods (e.g., Wi-Fi) is widely used.

Therefore, it may be necessary to use a technology to actively utilize the characteristics of the dual mode terminal in a heterogeneous network.

For example, in a heterogeneous network environment, there may be a need for a technology that allows dual-mode terminals having a Wi-Fi communication function and a cellular communication function to access a small-cell base station through a Wi-Fi communication function.

One aspect of the disclosure may include a method of operating a dual mode terminal. The method includes the steps of: linking a first dual mode terminal with a first base station through a D2D (Device-to-Device) link with at least one second dual mode terminal and a second base station; The first dual mode terminal receiving a relay request frame from the at least one second dual mode terminal via each D2D link; And establishing a relay for allowing the first dual mode terminal to communicate with the first base station and the relay target terminal - one of the at least one second dual mode terminal.

The first base station may be a small cell base station and the second base station may be a macro cell base station.

For example, the second dual mode terminal may be a dual mode terminal without access rights to the first base station. In another example, the second dual mode terminal may be a dual mode terminal located outside the service area of the first base station.

The method may further include the step of broadcasting, via each D2D link, a frame for informing a neighboring dual mode terminal of a relay invite frame-relay enabled by the first dual mode terminal.

The D2D link may include a link connected by a Wi-Fi direct communication method.

The relaying step may include setting up a relay using the cellular-based communication method in the link between the first base station and the first dual mode terminal and using the Wi-Fi direct communication method in the link between the first dual mode terminal and the relay target terminal . &Lt; / RTI >

Selecting a communication method to be used in a link between the first dual mode terminal and the relay target terminal among the WiFi direct communication method and the cellular based D2D communication method; And establishing a relay using the cellular based communication method in the link between the first base station and the first dual mode terminal and using the selected communication method in the link between the first dual mode terminal and the relay target terminal. The relay request frame includes information on a link state according to a Wi-Fi direct communication scheme and a link state according to a cellular-based D2D communication scheme, and the step of selecting a communication scheme includes: And a step of selecting the step.

Wherein the step of connecting to the D2D link comprises connecting each of the plurality of second dual mode terminals with a respective D2D link, and the step of receiving the relay request frame comprises receiving a relay request frame from the plurality of second dual mode terminals Wherein the setting of relaying comprises: selecting one of the plurality of second dual mode terminals; And establishing a relay for allowing the first base station and the selected second dual mode terminal to communicate.

The relay request frame includes information on the D2D link state of the corresponding second dual mode terminal, and the step of selecting includes selecting one of the plurality of second dual mode terminals based on the information on the D2D link state . &Lt; / RTI >

The method may further include the step of broadcasting, through each D2D link, a frame for informing the neighboring dual mode terminal of the relay invitation frame-relay enabled by the first dual mode terminal. The relay invitation frame may include information on the relay invitation period. The selecting may include selecting one of the second dual mode terminals that has transmitted the relay request frame within the relay invitation period.

The relay invite frame may be a WiFi direct-based management frame including a peer-to-peer group BSSID (basic set service ID) attribute, a P2P device information attribute, and a P2P group identifier attribute.

The relay invitation frame may be a Wi-Fi direct-based management frame including information on the relay invitation period as a P2P attribute.

The step of establishing the relaying may include establishing a relay for the second dual mode terminal that has first transmitted the relay request frame.

The relay request frame may be a WiFi direct based management frame that includes information on the D2D link status as a P2P attribute.

The method may further include transmitting a relay response message to each second dual mode terminal through which the first dual mode terminal transmits the relay request frame through the corresponding D2D link.

The relay response frame may be a WiFi direct-based management frame including a flag indicating whether the connection is allowed or not as a P2P attribute.

The relay request frame and the relay response frame may be WiFi direct based management frames having different organizationally unique identifier (OUI) subtype values.

The step of establishing the relay may further include the step of the first dual mode terminal transmitting the relay start frame for informing the relay destination terminal of the data transmission time. The relay start frame may be a WiFi direct based management frame including a status attribute, a P2P capability attribute, and a P2P group identifier attribute.

This Summary is provided to introduce any of the concepts further described in the following detailed description in a simplified form. This Summary is not intended to identify key features or essential features of the claimed subject matter nor is it intended to be used to limit the scope of the claimed subject matter. Furthermore, the claimed subject matter is not limited to implementations that solve some or all of the problems mentioned in any part of this specification. In addition to the exemplary aspects, embodiments, and features described above, additional aspects, embodiments, and features will become apparent with reference to the following detailed description and drawings.

Some embodiments of the present disclosure may have effects that include the following advantages. It should be understood, however, that the scope of the present invention should not be construed as being limited thereby.

According to some embodiments, the present invention can simplify the process of connecting a mobile terminal to a small cell base station in a HetNets environment, thereby providing a fast D2D connection setup.

According to some embodiments, by expanding the opportunities of small cell base station access, it is possible to increase the effect of distributing cellular data traffic concentrated in macro base stations to small cell base stations.

According to some embodiments, the radio resource in the cellular network for D2D communication is replaced with the license-exempt frequency band of Wi-Fi, thereby reducing the use of radio resources in the cellular network, thereby securing additional available radio resources.

According to some embodiments, the mobile terminal capable of dual communication mode and corresponding functions for small cell base station and macro cell base station can be implemented in a software manner, so that there is no additional hardware implementation and cost burden.

According to some embodiments, the data traffic load concentrated on the macro base station can be effectively distributed through the small cell through Wi-Fi technology using the license-free frequency band, and the cellular network operator can flexibly utilize the technology according to the network operation plan have.

Figure 1 illustrates a heterogeneous network environment for illustrating some embodiments.
2 illustrates the device search operation presented in the Wi-Fi standard.
3 is a view for explaining a bypass transmission path according to an embodiment.
4A and 4B are diagrams for explaining a relay setup method using a dual mode terminal in a heterogeneous network according to some embodiments.
FIG. 5A illustrates a management frame format defined in the WiFi Direct specification, and FIG. 5B illustrates an example of using an OUI subtype according to an embodiment.
FIG. 6A illustrates a P2P attribute structure included in a relay invitation frame according to an exemplary embodiment of the present invention, and FIG. 6B illustrates a P2P attribute related to a relay invitation frame according to an exemplary embodiment.
FIG. 7A illustrates a P2P attribute structure included in a relay request frame according to an exemplary embodiment, and FIG. 7B illustrates a P2P attribute related to a relay request frame according to an exemplary embodiment.
FIG. 8A illustrates a P2P attribute structure included in a relay response frame according to an exemplary embodiment, and FIG. 8B illustrates a P2P attribute related to a relay response frame according to an exemplary embodiment.
FIG. 9A illustrates a P2P attribute structure included in a relay start frame according to an embodiment, and FIG. 9B illustrates a P2P attribute related to a relay start frame according to an exemplary embodiment.

In the following detailed description, reference is made to the accompanying drawings which form a part of this disclosure. In the drawings, like symbols generally denote like elements unless the context clearly indicates otherwise. The illustrative embodiments set forth in the description, drawings, and claims are not intended to be limiting. Other embodiments may be used and other changes may be made without departing from the scope and spirit of the objects set forth in this disclosure. Aspects of the present disclosure, as generally described herein and illustrated in the figures, may be arranged, substituted, combined, separated and designed in a wide variety of different configurations, all of which are expressly contemplated in the present disclosure Will be clearly understood.

In a heterogeneous network, data traffic that has been concentrated in a conventional cellular network to a macro base station can be distributed through small cell base stations.

In order to maximize the load distribution through the small cell, data of mobile terminals located in the boundary of the small cell service area or in the small cell service area but lacking the right to access the small cell base station is stored in the small cell service area, A method in which terminals having access rights to a base station relay terminals using D2D communication can be used. As a result, there is a possibility that the intra-network data traffic concentrated in the macro base station can be efficiently distributed to the small-cell base station because the number of mobile terminals that can connect to the small cell base station through the bypass transmission path increases. However, since the existing cellular network standard is specialized in the centralized network management based on the base station, there are various issues to be solved for base station based D2D communication such as radio resource allocation for D2D communication and link establishment between devices. That is, there is a limit to expanding opportunities for mobile terminals to access small cell base stations using cellular based D2D communication.

In addition to cellular-based D2D communication, the Wi-Fi Alliance defines Wi-Fi Direct, a D2D communication standard based on Wi-Fi technology. In the existing Wi-Fi network, Wi-Fi direct technology has always required communication between mobile terminals via AP (Access Point) It is possible to directly communicate with terminals in the Wi-Fi network. However, due to lack of a service environment that can utilize Wi-Fi direct technology, various services are not provided.

Figure 1 illustrates a heterogeneous network environment for illustrating some embodiments.

As illustrated in FIG. 1, in a heterogeneous network environment, a macro base station (Macro BS, small cell BS, femtocell base station (Femto BS), dual mode terminal (cellular communication system, (All possible user terminals) and a single mode terminal (with only cellular communication function) can be distributed.

Examples of other communication methods include a Wi-Fi based communication method. Examples of the Wi-Fi based communication method include a Wi-Fi based D2D (Device-to-Device) communication method such as Wi-Fi direct , But is not limited thereto.

It is to be understood that the present disclosure is intended to disclose some embodiments, with the understanding that the dual mode terminal supports cellular communication and Wi-Fi direct-based communication, but it should be appreciated that the techniques of this disclosure may also accommodate communication methods other than Wi- If you are in this field, you can understand it.

The dual mode terminals can establish a Wi-Fi direct link and perform communication independently of the cellular communication link. Examples of the process of establishing a Wi-Fi direct link include a Wi-Fi Alliance (Peer-to-Peer technical group, Wi-Fi Peer-to-Peer technical specification v1.1, Oct. 2010.) And a device discovery procedure.

2 illustrates the device search operation presented in the Wi-Fi standard.

2 is a block diagram of a Wi-Fi Alliance, P2P technical group, Wi-Fi Peer-to-Peer (P2P) technical specification v1.1, Oct. 2010.), which represents a device search procedure.

The device search procedure defines a process of searching for neighboring terminals by the terminal. First, the terminal (for example, P2P Device 1 in FIG. 2) transitions to a scan state to perform a device search procedure, and searches for all neighboring terminals for all of the Wi-Fi communication channels.

If the terminal fails to find a neighboring terminal (e.g., P2P Device 2 in FIG. 2) in a scan state, it transitions to a listening state and transmits a response message to the mobile station through the social channels (channels 1, 6, 11) And waits for a frame to be transmitted from a neighboring terminal during a randomly selected dwell time within a predetermined interval in the selected social channel (e.g., channel 1 in FIG. 1).

If the terminal fails to find a neighboring terminal in the reception waiting state, it transitions to a search state. In the search state, the terminal sequentially transmits a probe request frame to the social channels (channels 1, 6, and 11), and upon receiving a probe response frame responding from another terminal, It is possible to know whether or not the terminal exists. A group owner (GO) may be determined between the UEs as a group formation procedure is developed as needed. The group owner selects an operation channel of the group as an AP (Access Point) -like entity And transmits a beacon frame.

FIG. 3 is a diagram for explaining a bypass transmission path according to one embodiment. More specifically, FIG. 3 illustrates a bypass mode in which a first dual mode (D_SUE- 1) A bypass transmission path through which the macro cell terminal D_MUE-1 and the small cell base station (smallcell BS) communicate is illustrated.

3, the first and second dual-mode small-cell terminals D_SUE-1 and D_SUE-2 are located in the small cell service area and have a right to access the small cell base station (hereinafter referred to as a small cell base station access right) 1 dual mode macro cell terminal D_MUE-1 maintains a WiFi direct link with the first dual mode small cell terminal D_SUE-1 but is located outside the small cell service area and the second dual mode macro cell terminal D_MUE- -2) does not have a small cell base station access right, some embodiments will be described.

In one embodiment, only the terminals located in the small cell service area and having the small cell base station access right can be set as the group owner. In this case, only the first and second dual mode small cell terminals D_SUE-1 and D_SUE-2 among the dual mode terminals D_SUE-1, D_SUE-2, D_MUE-1 and D_MUE- Lt; / RTI >

First, a first dual mode macro cell terminal (D_MUE-1) which desires to connect to a small cell base station among the dual mode terminals (D_MUE-1 and D_MUE-2) not belonging to the group owner, It is possible to transmit a relay request frame through the Wi-Fi direct link to the mode small cell terminal (D_SUE-1). The relay request frame may include a relay request message.

Next, the first dual-mode small-cell terminal D_SUE- 1 transmits a relay response frame to the first dual-mode macro-cell terminal D_MUE-1 via the Wi-Fi direct link in response to the reception of the relay request frame, Can be transmitted. The relay response frame may include a relay response message including relay availability.

In this case, the first dual-mode small-cell terminal D_SUE- 1 transmits the data of the first dual-mode macro cell terminal D_MUE-1 via the bypass path (the transmission path shown in bold solid lines in FIG. 3) for cellular data of MUE. 3, the bypass transmission path includes a first link (link between the base station and the relay terminal) and a second link (link between the relay terminal and the relaying terminal). The link between the small-cell BS (Small Cell BS) and the first dual-mode small-cell terminal (D_SUE-1), which is the first link, is a cellular link using cellular communication. However, the first dual-mode small- 1) and the first dual mode macro cell terminal (D_MUE-1) can be used for communication links of different types (first and second types). In one example, the first type of communication link may be a pre-established Wi-Fi direct link, and the second type of link may be a cellular-based D2D link. In Figure 3, the cellular-based D2D link is referred to as the cellular D2D virtual link, since it has not yet been established. Since both of the terminals D_SUE-1 and D_MUE-1 are dual-mode terminals, a bypass path can be formed by setting a cellular-based D2D link if necessary. The first dual-mode small-cell terminal (D_SUE-1) can select a superior capacity link among the Wi-Fi direct link and the cellular-based D2D virtual link. This link selection process will be described later.

If the WiFi direct link is selected as the communication type for the second link, the first dual mode macro cell terminal (D_SUE-1) is relayed by relaying the first dual mode small cell terminal (D_SUE-1) via the bypass transmission path including the Wi- D_MUE-1) and the small cell base station (Smallcell BS) can be performed. For example, the first dual-mode macro cell terminal D_MUE-1 transmits data to the first dual-mode small-cell terminal D_SUE- 1 through the Wi-Fi direct link maintained, D_SUE-1) can transmit data received from the first dual-mode macro cell terminal (D_MUE-1) through the cellular link to the small cell base station (Smallcell BS).

If the cellular D2D virtual link is selected as the communication type for the second link, then the cellular based D2D link is established and the first dual mode small cell terminal (D_SUE-1) via the bypass transmission path comprising the established cellular based D2D link Communication between the first dual mode macro cell terminal (D_MUE-1) and the small cell base station (Smallcell BS) can be performed by relay.

4A and 4B are diagrams for explaining a relay setup method using a dual mode terminal in a heterogeneous network according to some embodiments. 4A and 4B illustrate a case where the first dual mode small cell terminal D_SUE-1 is connected to the first dual mode macro cell terminal D_MUE-1 in the network environment of FIG. And D2D connection according to the proposed method by setting a Wi-Fi direct link of the macro cell terminal (D_MUE-2).

In the network environment of FIG. 3, the first dual mode macro cell terminal D_MUE-1, the second dual mode macro cell terminal D_MUE-2, the first dual mode small cell terminal D_SUE-1, The first dual mode small cell terminal D_SUE- 1 and the second dual mode small cell terminal D_SUE- 2 operate as independent group group owners The description will be made on the basis of the circumstances. The first and second dual-mode small-cell terminals D_SUE- 1 and D_SUE- 2, which are group owners, are initially in a listen state, such as when no terminals are connected or when a session is terminated I presume the environment.

The first and second dual mode macro cell terminals D_MUE-1 and D_MUE-2 recognize that there is a small cell base station in the periphery and are connected to a small-cell base station by a dual mode small- The first and second dual-mode small-cell terminals D_SUE-1 and D_SUE- 2 are connected to the Wi-Fi direct connection terminal through provisioning, Thereby forming a direct link. The process up to the formation of the Wi-Fi direct link can be performed by a procedure according to the Wi-Fi Direct Standard, and thus a detailed description thereof will be omitted.

Some embodiments illustrated in FIG. 4A include a method of selecting a relay target terminal after all the relay requests of the terminals requiring relay are received by the first dual-mode small-cell terminal (D_SUE-1) Some embodiments illustrated in FIG. 1 include a method of starting a relay setting immediately after the first dual-mode small-cell terminal (D_SUE-1) receives a relay request of terminals requiring relay, do.

Referring to FIG. 4A, the first dual-mode small cell terminal D_SUE- 1 broadcasts a Relaying Invitation frame. The relay invitation frame may include a message that the relay enabled terminal (e.g., D_SUE- 1) informs the existence of the relay presence terminal and transmits a relay request frame to peripheral terminals requiring relay (hereinafter, referred to as a relay required terminal). The relay invitation frame may further include relaying invitation period information.

In step S620, the relay required terminal (e.g., D_MUE-1) transmits a relay request frame to the terminal (e.g., D_SUE-1) that has transmitted the relay invite frame in response to receiving the relay invite frame. For example, when the relay enabled terminal only receives the relay request frame received within the relay invitation period, the relay required terminal must transmit the relay request frame within the relay invitation period.

In one embodiment, the relay request frame may include terminal selection information used in selecting a relay target terminal among terminals (hereinafter referred to as relay request terminals) that have transmitted a relay request message. In one embodiment, the terminal selection information may be information for grasping the link status of the relay request terminal. In this case, the relay enabled terminal can select a relay request terminal whose relay link state is maintained or predicted as a relay destination terminal. For example, an example of information for grasping link status may include information for predicting the capacity of a corresponding communication link (e.g., Wi-Fi direct link, cellular based D2D link). Examples of the information for predicting the capacity of the WiFi direct include a received signal strength (RSS) measured at the time of receiving a relay invite frame, a modulation and coding scheme (MCS) level available when transmitting a data frame, . Examples of the information for predicting the capacity of the cellular-based D2D link include information on the amount of resources that can be allocated from the macro base station, link state information with the existing macro base station (e.g. RSS of the signal received from the macro base station, MCS level, etc.).

Next, the relay enabled terminal (e.g., D_SUE- 1) selects an appropriate relay destination terminal based on the received relay request frames until the relay invitation period expires.

When there are a plurality of relay request terminals, the relay capable terminal (e.g., D_SUE-1) can select the relay request terminal having the best state (capacity, throughput, or transmission rate) . For example, the relay enabled terminal can select the relay destination terminal based on the terminal selection information included in the relay request frame.

In one embodiment, the relay enabled terminal selects the relay request terminal having the best Wi-Fi direct link status as the relay target terminal. This is because it is expected that the relay between the relayable terminal and the relayed terminal will frequently utilize the Wi-Fi direct link in a general situation, and the use of the cellular D2D link may be caused by a situation in which the Wi- In order to use it selectively in consideration of situations in which the transmission capability is very low.

In one embodiment, if the relay enabled terminal determines that the data transmission efficiency of the relay destination selection terminal using the bypass transmission path is lower than the transmission efficiency of the link with the existing macro base station, based on the information included in the relay request frame , You can refuse to relay. Such information may be included in a relay response frame transmitted to each relay requesting terminal by the relay capable terminal after the relay invitation period expires.

The relay response frame may include a flag indicating whether or not the connection is permitted (i.e., whether to provide a relay service). In one embodiment, the relay response frame includes a flag indicating that access is allowed only to the relay request frame to be transmitted to the relay request terminal having the best WIFI direct link, and a flag indicating that access is impossible is included in the relay response frames to be transmitted to the remaining terminals do. In another embodiment, when the efficiency of the bypass transmission path of the relay requesting terminal having the best link is poor, a flag indicating that the access request can not be connected to the relay request frame to be transmitted to the relay requesting terminal having the best link may be included have.

Referring to FIG. 4A, when the first invitation period expires and the transmission process of the relay response frame ends, the relay target terminal can be determined as the first dual mode macro cell terminal D_MUE-1 as in the situation of FIG. 3 .

Next, the first dual mode macro cell terminal D_MUE- 1 transmits a Relaying Initiation frame including a message for triggering the start of data relay from the first dual mode small cell terminal D_SUE- 1, It is possible to start data frame transmission. Data frame transmission may involve an ACK response process.

As shown in FIG. 4A, the second dual mode macro cell terminal D_MUE-2 not selected from the first dual-mode small-cell terminal D_SUE-1 during this series of processes is connected to another relayable terminal (D_SUE-2 in FIG. 4A) searches for another group having the group owner, and can receive a bypass transmission path through the relayable terminal (D_SUE-2 in FIG. 4A).

FIG. 4B illustrates another method of selecting a relay target terminal through a link establishment process through Wi-Fi direct in the environment of FIG. 3 as shown in FIG. 4A. According to some embodiments of FIG. 4A, the relay enabled terminal receives a relay request message from neighboring terminals, selects an appropriate relay request terminal, and provides a relay service to the corresponding terminal. On the other hand, according to some embodiments of FIG. 4B, the relay enabled terminal provides a relay service to the relay request terminal that transmitted the first relay request frame.

4B, although the first dual mode macro cell terminal D_MUE-1 first establishes the link through provisioning, since the second dual mode macro cell terminal D_MUE-2 first makes a relay request, The dual mode small cell terminal D_SUE- 1 first provides the relay service to the second dual mode macro cell terminal D_MUE- 2 and then the first dual mode macro cell terminal D_MUE- Can provide the relay service to the user.

4A, the scheme according to FIG. 4B has fewer newly required frames (for example, a relay invite frame and a relay start frame), and provides an opportunity to use a fair detour route for relatively in-group terminals There is an advantage to be able to do.

The scheme according to FIG. 4B may be more effective than the scheme according to FIG. 4A when there are few relayable terminals.

In the method according to FIG. 4B, the process of determining whether the relay enabled terminal can relay can be the same as the method according to FIG. 4A. As an example, as in some embodiments of FIG. 4A, the scheme of FIG. 4B includes an example of finding a group owner of another group and providing a bypass path if necessary.

In one embodiment, the relay invite frame, the relay request frame, the relay response frame, and the relay start frame may be management frames.

FIG. 5A illustrates a management frame format defined in the WiFi Direct specification, and FIG. 5B illustrates an example of using an OUI subtype according to an embodiment.

In one embodiment, when a relay invite frame, a relay request frame, a relay response frame, and a relay start frame are used as management frames, a relay invite frame, a relay request frame, a relay response frame, The frames may include values of OUI Subtype (9, 10, 11, 12, respectively, referring to FIG. 5B) to be distinguished from other frames.

In one embodiment, the relay invite frame, the relay request frame, the relay response frame, and the relay start frame may include at least one P2P attribute.

FIG. 6A illustrates a P2P attribute structure included in a relay invitation frame according to an exemplary embodiment of the present invention, and FIG. 6B illustrates a P2P attribute related to a relay invitation frame according to an exemplary embodiment.

In one embodiment, the relay invite frame is different from the Invitation Request frame. It may not include an attribute related to the operation channel.

In one embodiment, the relay invite frame may include an Invitation Time attribute. The invitation time attribute may include information on the above-mentioned invitation invitation period.

In an exemplary embodiment, the relay invite frame may include a P2P group BSSID attribute, a P2P device information attribute, and a P2P group identifier attribute.

FIG. 7A illustrates a P2P attribute structure included in a relay request frame according to an exemplary embodiment, and FIG. 7B illustrates a P2P attribute related to a relay request frame according to an exemplary embodiment.

In one embodiment, the relay request frame may not include an attribute related to the operation channel, unlike the invitation request frame.

In one embodiment, the relay request frame may include a D2D Selection attribute. The D2D selection attribute includes resource information indicating the amount of resources received from the macro base station by the macro P2P terminal, and Cellular Link Quality information indicating the link status with the macro base station, and allocated 2 bytes and 8 bytes, respectively.

FIG. 8A illustrates a P2P attribute structure included in a relay response frame according to an exemplary embodiment, and FIG. 8B illustrates a P2P attribute related to a relay response frame according to an exemplary embodiment.

In one embodiment, the relay response frame may include a Selection Flags attribute, unlike the Invitation Response frame. The selection flag attribute includes a selection flag, which is information for indicating a response to the relay request. When the selection flag value is 1, connection permission is indicated. When the selection flag is 0, connection is disabled.

FIG. 9A illustrates a P2P attribute structure included in a relay start frame according to an embodiment, and FIG. 9B illustrates a P2P attribute related to a relay start frame according to an exemplary embodiment.

In one embodiment, the relay start frame may include a status attribute, a P2P capability attribute, and a P2P group identifier attribute, as in a group negotiation confirmation frame (GO Negotiation Confirmation frame).

Skilled artisans will appreciate that in the present processes and methods and other processes and methods disclosed herein, the functions performed in the processes and methods may be implemented in different orders. It should also be understood that the steps and operations outlined above are provided by way of example only and that certain steps and operations are optional and may be combined in fewer steps and operations or may be combined with additional steps and operations without departing from the essence of the disclosed embodiments Can be expanded.

In an exemplary embodiment, any of the operations, processes, and the like described in this disclosure may be implemented with computer-readable instructions stored on a computer-readable medium. The computer-readable instructions may be executed by a processor, a network component, and / or any other computing device of the mobile device.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. I will understand that. Accordingly, the true scope of the present invention should be determined by the appended claims.

Claims

A method for operating a dual mode terminal,
Connecting to a first dual mode terminal through a D2D (Device-to-Device) link with a second dual mode terminal connected to a first base station;
The first dual mode terminal receiving a relay request frame from the at least one second dual mode terminal via each D2D link; And
And establishing a relay for allowing the first dual mode terminal to communicate with the first base station and the relay target terminal - one of the at least one second dual mode terminal.

The method according to claim 1,
Wherein the first base station is a small cell base station and the second base station is a macro cell base station.

3. The method according to claim 1 or 2,
Wherein the second dual mode terminal is a dual mode terminal without access rights to the first base station.

3. The method according to claim 1 or 2,
Wherein the second dual mode terminal is a dual mode terminal located outside the service area of the first base station.

The method according to claim 1,
And broadcasting the frame for informing the neighboring dual mode terminal of the relay invite frame-relay enabled by the first dual mode terminal through each D2D link.

The method according to claim 1,
Wherein the D2D link comprises a link connected in a Wi-Fi direct communication manner.

The method according to claim 1,
Wherein the relaying step uses a cellular based communication method in a link between the first base station and the first dual mode terminal and uses a Wi-Fi direct communication method in a link between the first dual mode terminal and the relay target terminal And establishing a relay.

The method of claim 1, wherein the step of establishing the relay
Selecting a communication method to be used in a link between the first dual mode terminal and the relay target terminal among the WiFi direct communication method and the cellular based D2D communication method; And
And establishing a relay using the selected communication method in the link between the first dual mode terminal and the relay target terminal using the cellular based communication method in the link between the first base station and the first dual mode terminal How to.

9. The method of claim 8,
Wherein the relay request frame includes information on a link state according to the Wi-Fi direct communication scheme and a link state according to the cellular-based D2D communication scheme,
Wherein the step of selecting the communication scheme comprises selecting a communication scheme to be used based on the information on the link status.

The method according to claim 1,
Wherein the step of connecting to the D2D link comprises connecting each of the plurality of second dual mode terminals through a respective D2D link,
Wherein the step of receiving the relay request frame comprises receiving the relay request frame from the plurality of second dual mode terminals,
Wherein the setting of the relaying comprises: selecting one of the plurality of second dual mode terminals; And establishing a relay for allowing the first base station and the selected second dual mode terminal to communicate.

11. The method of claim 10,
Wherein the relay request frame includes information on a D2D link state of the second dual mode terminal,
Wherein the selecting comprises selecting one of the plurality of second dual mode terminals based on information on the D2D link state.

11. The method of claim 10,
Further comprising the step of broadcasting, through each of the D2D links, a frame for notifying the neighboring dual mode terminal that the first dual mode terminal is capable of relay invite frame relaying,
Wherein the relay invitation frame includes information on a relay invitation period,
Wherein the selecting comprises selecting one of the second dual mode terminals that has transmitted the relay request frame within the relay invitation period.

13. The method of claim 12,
Wherein the relay invite frame is a Wi-Fi direct-based management frame including a P2P group BSSID attribute, a P2P device information attribute, and a P2P group identifier attribute.

13. The method of claim 12,
Wherein the relay invite frame includes information about the relay invite period as a P2P attribute.

The method according to claim 1,
Wherein the establishing of the relay comprises establishing a relay for a second dual mode terminal that first transmitted the relay request frame.

The method according to claim 1,
Wherein the relay request frame is a Wi-Fi direct-based management frame including information on a D2D link status as a P2P attribute.

The method according to claim 1,
And transmitting the relay response message to each second dual mode terminal through which the first dual mode terminal transmits the relay request frame through the corresponding D2D link.

18. The method of claim 17,
Wherein the relay response frame is a WiFi direct-based management frame including a flag indicating whether or not to permit connection as a P2P attribute.

18. The method of claim 17,
Wherein the relay request frame and the relay response frame are WiFi direct based management frames having different OUI subtype values.

The method according to claim 1,
Wherein the setting of the relay further comprises the step of the first dual mode terminal transmitting a relay start frame for informing the relay destination terminal of the data transmission time.

19. The method of claim 18,
Wherein the relay start frame is a WiFi direct-based management frame that includes a status attribute, a P2P capability attribute, and a P2P group identifier attribute.