WO2017039379A1 - Scheduling method for data link of neighbor recognition network and device using same - Google Patents

Abstract

A scheduling method of a data link for NAN, according to one embodiment of the present invention, comprises a step in which: a first discovery frame is transmitted in a discovery interval to a second device, the first discovery frame comprising first scheduling information indicating a scheduling technique supportable by a first device; a second discovery frame is received in the discovery interval from the second device, the second discovery frame comprising second scheduling information and traffic information, the second scheduling information indicating a scheduling technique supportable by the second device, and the traffic information being on traffic to be transmitted from the second device to the first device; and if the second scheduling information indicates both a synchronization technique and a paging technique, the first device selects any one among the synchronization technique and the paging technique on the basis of the traffic information.

Description

      Scheduling method for data link of neighbor aware network and device using same

The present disclosure relates to wireless communication, and more particularly, to a scheduling method for a data link of a neighbor awareness network (NAN) and a device using the same.

Recently, with the development of information and communication technology, various wireless communication technologies have been developed. In particular, a wireless local area network (WLAN) is a technology that enables wireless access to the Internet in a home, business, or specific service providing area using a portable terminal based on radio frequency technology.

For example, the portable terminal may be a personal digital assistant (PDA), a laptop, a portable multimedia player (PMP). In general, communication between terminals in a WLAN system is performed through a management entity such as a base station or an access point. The management medium is responsible for scheduling for data communication.

      In order to secure the flexibility of the communication between terminals in a WLAN system, various protocols for direct communication between terminals without a management medium have been proposed. NAN is a standard established by the Wi-Fi Alliance (WFA) based on the Wi-Fi standard. The NAN specification provides for synchronization and discovery procedures between devices in the 2.5 GHz or 5 GHz frequency band.

An object of the present specification is to provide a scheduling method and a device using the data link for a neighbor aware network with improved performance.

       This specification relates to a scheduling method for a data link of a NAN. In the scheduling method for a data link according to the present embodiment, a first discovery frame including first scheduling information indicating a scheduling scheme supported by a first device is transmitted to a second device in a discovery interval, Receiving a second discovery frame from the second device in the discovery period, the second discovery frame including second scheduling information indicating a scheduling scheme supported by the second device and traffic information of traffic to be transmitted from the second device to the first device, 2 If the scheduling information indicates both a synchronization scheme and a paging scheme, the first device includes selecting one of a synchronization scheme and a paging scheme based on the traffic information, wherein the synchronization scheme includes: After the discovery period ends, the first device and the second device enter the data section for traffic at the same time when they are synchronized. And, paging scheme, then the search interval is terminated when a method of pre-defined offset time elapses, the first device transmits a paging message to the second device for receiving the traffic.

      According to the present embodiment, negotiation of an available scheduling scheme may be performed based on capability exchange between NAN terminals. In addition, an appropriate scheduling scheme may be selected according to a traffic characteristic to be delivered to another NAN terminal. Accordingly, a scheduling method for a data link of a neighbor aware network having improved performance and a device using the same can be provided.

       1 is a conceptual diagram illustrating a structure of a WLAN system.

      2 is a conceptual diagram of a layer architecture of a WLAN system supported by IEEE 802.11.

       3 is a conceptual diagram illustrating a channel access technique of an STA based on DCF.

4 is a conceptual diagram illustrating a channel access model according to EDCA.

5 and 6 are diagrams illustrating a NAN cluster.

7 is a block diagram of a structure of a NAN terminal.

8 and 9 illustrate relationships between NAN components.

10 shows a NAN data communication structure for data transmission and reception between NAN terminals.

11 shows an operation of a NAN terminal in a search window and a search window interval.

12 and 13 illustrate an NDL scheduling scheme of a NAN terminal.

14 and 15 illustrate a conceptual diagram of a scheduling technique of a NAN terminal according to an embodiment of the present disclosure.

16 is a flowchart illustrating a scheduling method of a NAN terminal according to one embodiment of the present specification.

17 is a flowchart illustrating specific steps in a scheduling method of a NAN terminal according to an embodiment of the present specification.

18 is a diagram illustrating a field of a TSPEC element according to an embodiment of the present specification.

19 illustrates a subfield of a TSPEC element according to another embodiment of the present specification.

20 is a block diagram illustrating a wireless device in which an embodiment of the present specification can be implemented.

The above-described features and the following detailed description are all exemplary for ease of description and understanding of the present specification. That is, the present specification is not limited to this embodiment and may be embodied in other forms. The following embodiments are merely examples to fully disclose the present specification, and are descriptions to convey the present specification to those skilled in the art. Thus, where there are several methods for implementing the components of the present disclosure, it is necessary to clarify that any of these methods may be implemented in any of the specific or equivalent thereof.

In the present specification, when there is a statement that a configuration includes specific elements, or when a process includes specific steps, it means that other elements or other steps may be further included. That is, the terms used in the present specification are only for describing specific embodiments and are not intended to limit the concept of the present specification. Furthermore, the described examples to aid the understanding of the invention also include their complementary embodiments.

The terminology used herein has the meaning commonly understood by one of ordinary skill in the art to which this specification belongs. Terms commonly used should be interpreted in a consistent sense in the context of the present specification. In addition, terms used in the present specification should not be interpreted in an idealistic or formal sense unless the meaning is clearly defined. Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings.

1 is a conceptual diagram illustrating a structure of a WLAN system. FIG. 1A shows the structure of an infrastructure network of the Institute of Electrical and Electronic Engineers (IEEE) 802.11.

Referring to FIG. 1A, the WLAN system 10 of FIG. 1A may include at least one basic service set (hereinafter, referred to as 'BSS', 100, 105). The BSS is a set of access points (APs) and stations (STAs) that can successfully synchronize and communicate with each other, and is not a concept indicating a specific area.

For example, the first BSS 100 may include a first AP 110 and one first STA 100-1. The second BSS 105 may include a second AP 130 and one or more STAs 105-1, 105-2.

The infrastructure BSS (100, 105) may include at least one STA, AP (110, 130) providing a distribution service (Distribution Service) and a distribution system (DS, 120) connecting a plurality of APs. have.

The distributed system 120 may connect the plurality of BSSs 100 and 105 to implement an extended service set 140 which is an extended service set. The ESS 140 may be used as a term indicating one network to which at least one AP 110 or 130 is connected through the distributed system 120. At least one AP included in one ESS 140 may have the same service set identification (hereinafter, referred to as SSID).

The portal 150 may serve as a bridge for connecting the WLAN network (IEEE 802.11) with another network (for example, 802.X).

In a WLAN having a structure as shown in FIG. 1A, a network between APs 110 and 130 and a network between APs 110 and 130 and STAs 100-1, 105-1, and 105-2 may be implemented. Can be.

1B is a conceptual diagram illustrating an independent BSS. Referring to FIG. 1B, the WLAN system 15 of FIG. 1B performs communication by setting a network between STAs without the APs 110 and 130, unlike FIG. 1A. It may be possible to. A network that performs communication by establishing a network even between STAs without the APs 110 and 130 is defined as an ad-hoc network or an independent basic service set (BSS).

Referring to FIG. 1B, the IBSS 15 is a BSS operating in an ad-hoc mode. Since IBSS does not contain an AP, there is no centralized management entity. Thus, in the IBSS 15, the STAs 150-1, 150-2, 150-3, 155-4, and 155-5 are managed in a distributed manner.

All STAs 150-1, 150-2, 150-3, 155-4, and 155-5 of the IBSS may be mobile STAs, and access to a distributed system is not allowed. All STAs of the IBSS form a self-contained network.

The STA referred to herein includes a medium access control (MAC) conforming to the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard and a physical layer interface to a wireless medium. As any functional medium, it can broadly be used to mean both an AP and a non-AP Non-AP Station (STA).

The STA referred to herein includes a mobile terminal, a wireless device, a wireless transmit / receive unit (WTRU), a user equipment (UE), and a mobile station (MS). It may also be called various names such as a mobile subscriber unit or simply a user.

2 is a conceptual diagram of a layer architecture of a WLAN system supported by IEEE 802.11. Referring to FIG. 2, a hierarchical architecture of a WLAN system includes a physical medium dependent (PMD) sublayer 200, a physical layer convergence procedure (PLCP) sublayer ( 210 and a medium access control (MAC) sublayer 220.

The PMD sublayer 200 may serve as a transmission interface for transmitting and receiving data between a plurality of STAs. The PLCP sublayer 210 is implemented such that the MAC sublayer 220 can operate with a minimum dependency on the PMD sublayer 200.

The PMD sublayer 200, the PLCP sublayer 210, and the MAC sublayer 220 may conceptually include management entities. For example, the management unit of the MAC sublayer 220 is referred to as a MAC Layer Management Entity (MLME) 225. The management unit of the physical layer is referred to as a PHY Layer Management Entity (PLME) 215.

Such management units may provide an interface for performing a layer management operation. For example, the PLME 215 may be connected to the MLME 225 to perform management operations of the PLCP sublayer 210 and the PMD sublayer 200. The MLME 225 may be connected to the PLME 215 to perform a management operation of the MAC sublayer 220.

In order for the correct MAC layer operation to be performed, a STA management entity (hereinafter, referred to as “SME”, 250) may exist. The SME 250 may operate as an independent component in each layer. The PLME 215, the MLME 225, and the SME 250 may transmit and receive information from each other based on primitives.

The operation of each sub-layer is briefly described as follows. For example, the PLCP sublayer 110 may include a MAC protocol data unit (MAC protocol data unit) received from the MAC sublayer 220 according to an indication of the MAC layer between the MAC sublayer 220 and the PMD sublayer 200. Hereinafter, the MPDU is transmitted to the PMD sublayer 200 or the frame coming from the PMD sublayer 200 is transferred to the MAC sublayer 220.

The PMD sublayer 200 may be a PLCP lower layer to perform data transmission and reception between a plurality of STAs over a wireless medium. The MPDU delivered by the MAC sublayer 220 is referred to as a physical service data unit (hereinafter, referred to as a PSDU) in the PLCP sublayer 210. The MPDU is similar to the PSDU. However, when an aggregated MPDU (AMPDU) that aggregates a plurality of MPDUs is delivered, individual MPDUs and PSDUs may be different from each other.

The PLCP sublayer 210 adds an additional field including information required by the transceiver of the physical layer in the process of receiving the PSDU from the MAC sublayer 220 and transmitting the PSDU to the PMD sublayer 200. In this case, the added field may be a PLCP preamble, a PLCP header, tail bits required to return the convolutional encoder to a zero state in the PSDU.

The PLCP sublayer 210 adds the above-described fields to the PSDU to generate a PPCP (PLCP Protocol Data Unit), which is then transmitted to the receiving station via the PMD sublayer 200, and the receiving station receives the PPDU to receive the PLCP preamble and PLCP. Obtain and restore information necessary for data restoration from the header.

3 is a conceptual diagram illustrating a channel access method of an STA based on DCF.

For example, in the 802.11 MAC layer, a plurality of STAs may share a wireless medium using a distributed coordination function (hereinafter, referred to as 'DCF') that is a contention-based function. The DCF may use carrier sense multiple access / collision avoidance (CSMA / CA) as an access protocol to coordinate collisions between STAs.

In the channel access scheme using DCF, when the medium is not in use for more than a DCF inter frame space (DIFS) period (ie, when the channel is idle during DIFS), the STA may transmit an MPDU that is about to be transmitted. If it is determined that the medium is in use by the carrier sensing mechanism of the STA, the STA determines the size of the contention window (hereinafter referred to as 'CW') by a random backoff algorithm and back. The off procedure can be performed.

The STA selects any time slot in the CW to perform the backoff procedure. The selected time slot is called the back off time. A STA that selects a relatively short backoff time among backoff times selected by a plurality of STAs may first obtain a transmission opportunity (hereinafter, referred to as 'TXOP') for accessing a medium.

The remaining STAs may stop the remaining backoff time and wait until the transmission of the STA transmitting the frame is completed. After the frame transmission of the STA is completed, the remaining STA again may compete with the remaining backoff time to occupy the wireless medium.

The DCF-based transmission method serves to prevent a collision that may occur when a plurality of STAs simultaneously transmit frames. However, the channel access scheme using DCF has no concept of transmission priority. That is, when DCF is used, the quality of service (QoS) of traffic to be transmitted by the STA cannot be guaranteed.

In order to solve this problem, a new coordination function (hybrid coordination function, hereinafter 'HCF') is defined in 802.11e. The newly defined HCF has improved performance over the channel access performance of the existing DCF. HCF can use two channel access techniques, HCCA controlled channel access (HCCA) and polling-based enhanced distributed channel access (EDCA), for improving QoS.

Traffic categories ('TC') for transmission priority in EDCA and HCCA may be defined. The priority for performing channel access may be determined based on the above TC.

Specifically, the HCCA technique uses a hybrid coordinator (hereinafter, referred to as 'HC') located in the AP for central management of wireless medium access. Since the HC centrally manages the wireless medium, the competition for wireless medium access between STAs can be reduced. As a result, data frame exchange can be maintained with a short transmission delay time (SIFS), thereby increasing network efficiency.

The HC controls transmission delay and scheduling by defining, as a parameter, QoS characteristics for specific traffic required from an application service for QoS support. Before transmitting the parameterized QoS traffic, the HC first establishes a virtual connection called a traffic stream. The traffic stream may be configured in both the uplink from the STA to the AP, the downlink from the AP to the STA, or the direct link from the STA to the STA.

In order to establish a traffic stream between the AP and the STA, traffic characteristics such as frame size, average transmission rate, and QoS request parameters such as delay time are exchanged through mutual negotiation. The HC uses TXOP to control the allocation of media access time.

4 is a conceptual diagram illustrating a channel access model according to EDCA. Referring to FIG. 4, the EDCA may perform channel access by defining a plurality of user priorities.

In EDCA, four access categories (hereinafter, 'AC') can be defined for the transmission of QoS traffic based on priority. For example, AC may be AC_BK, AC_BE, AC_VI or AC_VO.

Four transmission queues (411, 412, 413, 414) corresponding to the four ACs (AC_BK, AC_BE, AC_VI, AC_VO) shown in FIG. 4 serve as individual EDCA competition entities for wireless medium access within one STA. Can be performed. One AC may have a unique arbitration inter-frame space (AIFS) value and maintain an independent backoff counter. If there is more than one AC that has been backed off at the same time, collisions between the ACs may be controlled by a virtual collision handler 420.

EDCA can classify traffic of MAC layer having different user priorities as shown in Table 1 below based on AC.

Priority	User priority	Access category (access caategory, AC)
lowness	One	AC_BK
	2	AC_BK
	0	AC_BE
	3	AC_BE
	4	AC_VI
	5	AC_VI
	6	AC_VO
height	7	AC_VO

Transmission queues and AC parameters can be defined for each AC. EDCA can use AIFS [AC], CWmin [AC] and CWmax [AC] instead of DIFS, CWmin and CWmax, which are used in DCF, when performing the backoff procedure for transmitting traffic belonging to AC. have. Parameters used for the backoff procedure for each AC may be delivered from the AP to each STA in a beacon frame. The smaller the value of AIFS [AC] and CWmin [AC], the higher the priority. Therefore, the shorter the channel access delay, the more bandwidth can be used in a given traffic environment.

If a collision occurs between STAs while the STAs transmit frames, the backoff procedure of EDCA, which generates a new backoff counter, is similar to the backoff procedure of the existing DCF. AC-based differentiated EDCA backoff procedure may be performed based on other EDCA parameters. In other words, the EDCA parameter is an important means used to differentiate channel access of STAs having traffic having various user priorities.

5 and 6 are diagrams illustrating a NAN cluster. The NAN cluster may consist of NAN terminals using the same set of NAN parameters. For example, the NAN parameter may include interval information between successive discovery windows (hereinafter, referred to as 'DW'), information about a beacon interval, information about the NAN channel, and the like.

Referring to FIG. 5, the NAN cluster 510 may include a plurality of NAN terminals 520_1, 520_2, 520_3, and 520_4. NAN cluster 510 uses the same set of NAN parameters. The NAN cluster 510 may be a collection of a plurality of NAN terminals 520_1, 520_2, 520_3, and 520_4 synchronized to a schedule of the same search window DW.

Any one of the NAN terminals 520_1, 520_2, 520_3, and 520_4 of the NAN cluster 510 may have a multicast or unicast NAN service discovery frame within a range of a discovery window (DW). Hereinafter, 'SDF') may be directly transmitted to another NAN terminal.

Referring to FIG. 6, the NAN cluster 610 may include at least one NAN master 620_1 and 620_2, and the NAN master is at least one other NAN terminal in the same NAN cluster 610 through a series of processes. Can be changed to For example, the NAN master of the NAN cluster 610 of FIG. 6 may be changed to at least one other NAN terminal 620_2 or 620_4.

In addition, at least one NAN master may transmit all of a synchronization beacon frame, a discovery beacon frame, and a NAN service discovery frame. The sync beacon frame, the discovery beacon frame, and the NAN service discovery frame are described in more detail with reference to the following drawings.

7 is a block diagram of a structure of a NAN terminal according to an embodiment of the present disclosure. Referring to FIG. 7, the NAN terminal 700 may operate based on the physical layer 710 of 802.11. The NAN terminal 700 includes NAN medium access control (MAC) 720, a NAN engine 730, a plurality of applications (App_1, App_2, ..., App_n) and a plurality of applications (App_1, App_2, ..., App_n) may include a plurality of NAN APIs 741, 742,..., 74n respectively.

For the discovery operation of the NAN terminal and data communication with the counterpart NAN terminal, the NAN engine 730 is based on a NAN based on primitives received from a plurality of applications (App_1, App_2, ..., App_n) of the NAN terminal. The operation of the MAC 720 may be controlled.

8 and 9 illustrate relationships between NAN components. 8 and 9, the NAN MACs 820_1, 820_2, and 920 may process NAN beacon frames and NAN service discovery frames.

The NAN engines 830_1, 830_2, and 930 may process service requests (Queries) and responses. The NAN engines 830_1, 830_2, and 930 may provide functions of subscribe 931, follow-up 932, and publish 933. In addition, the NAN engines 830_1, 830_2, and 930 may provide various functions for scheduling data links according to an embodiment of the present specification.

The publish / subscribe 931, 933 functions operate based on the service interface provided from the service / application 940. When the instructions of the publish / subscribe 931, 933 are executed, an instance of the publish / subscribe 931, 933 function is generated.

Each instance runs independently, and depending on the implementation, several instances may run simultaneously. The follow-up 932 function sends and receives service specific information for the service / application 940.

10 shows a NAN data communication structure for data transmission and reception between NAN terminals. 5 and 10, a NAN Data Cluster (hereinafter referred to as 'NDC') 1000 may include at least two NAN terminals 1001, which share a common NDC schedule in the same NAN cluster 1100. 1002, 1003, 1004).

Each NAN terminal in the NDC 1000 has at least one NAN data link (hereinafter, 'NDL') with another terminal belonging to the same NDC. In this case, the NDL may mean a resource block (hereinafter, referred to as 'RB') negotiated between NAN terminals. The NAN terminal may establish an NDL with another NAN terminal to share an RB for data transmission and reception. Each NDL may have its own NDL schedule. The scheduling technique for the NDL schedule is described based on the drawings to be described below.

A NAN Data Path (hereinafter, referred to as 'NDP') may mean a data connection established for service between NAN terminals. NDP may be set to request a service between NAN terminals.

For example, the first NAN terminal 1001 has an NDL with the second to fourth NAN terminals 1002, 1003, and 1004. The second NAN terminal 1002 has an NDL with the first NAN terminal 1001 and the third NAN terminal 1003. The third NAN terminal 1003 has an NDL with the first NAN terminal 1001 and the second NAN terminal 1002. The fourth NAN terminal 1004 has an NDL with the first NAN terminal 1001.

The remaining NAN terminals 1005 to 1018 of the NAN cluster 1100 except for the NAN terminals 1001, 1002, 1003, and 1004 included in the NDC 1000 may transmit and receive control information associated with the NAN parameter. Substantial data such as payload cannot be transmitted or received.

11 shows an operation of a NAN terminal in a search window and a search window interval.

Referring to FIG. 11, the discovery window DW may be referred to as a time and channel where NAN terminals converge in a NAN cluster. The horizontal axis of FIG. 11 represents a time axis t, and a unit of the time axis is a time unit (TU). Although the vertical axis of FIG. 11 is not separately indicated, it will be understood that the presence of a frame transmitted by the NAN terminals in the NAN cluster exists.

In addition, it will be understood that the sync beacon frame (SBF), the discovery beacon frame (DBF) and the service discovery frame (SDF) transmitted by the NAN terminal of FIG. 11 may be transmitted through the same channel or through different channels. .

Referring to FIG. 11, the interval from the start point DWStart_1 to the end point DWEnd_1 of the first time window DW_1 may be 16 TU, and the first cycle of the next cycle may be performed from the end point DWEnd_1 of the first time window DW_1. The search window interval (DW interval) pointing between the start point DWStart_2 of the two time windows DW_2 may be 496 TUs.

 Similarly, the interval from the start point DWStart_2 to the end point DWEnd_2 of the second time window DW_2 of the next cycle may be 16 TU.

A synchronization beacon frame (SBF) is used for synchronization of NAN terminals in a NAN cluster. A discovery beacon frame (hereinafter referred to as 'DBF') is used to advertise a NAN terminal that is not joined to the NAN cluster so that the NAN cluster can be found. A service discovery frame (SDF) is used to exchange information about available services between NAN terminals.

At least one NAN terminal may transmit all of the NAN terminals in the NAN cluster by transmitting a synchronization beacon frame SBF during the discovery window DW. One NAN terminal may transmit one sync beacon frame SBF during one discovery window DW.

The at least one NAN terminal may transmit at least one discovery beacon frame DBF in the discovery window interval DW_interval. Accordingly, the NAN terminals belonging to other NAN clusters can discover the NAN cluster to which the NAN terminal which transmitted the discovery beacon frame (DBF) belongs. In addition, the NAN terminals not belonging to the NAN cluster may discover the NAN cluster to which the NAN terminal which transmitted the discovery beacon frame (DBF) belongs.

The NAN terminal may transmit a service discovery frame SDF on a contention basis during the discovery window DW. The NAN terminal may start a backoff timer set to an arbitrary value and transmit a service discovery frame (SDF) when the value of the backoff timer becomes zero.

The service discovery frame (SDF) may include any one of two NAN service discovery protocol messages.

For example, the NAN Service Discovery Protocol message may be a subscribe message to actively confirm the availability of a particular service. Alternatively, the NAN service discovery protocol message may be a publish message transmitted when response criteria of the NAN terminal that receives the subscribe message are satisfied.

However, a publish message may be used to enable other NAN devices operating in the same NAN cluster to discover available services of the NAN terminal that transmits a publish message.

 For the sake of brevity, hereinafter, a service discovery frame (SDF) containing a subscribe message is referred to as a subscription frame, and a service discovery frame (SDF) containing a publish message is referred to as a publish frame. Is mentioned.

12 and 13 illustrate an NDL scheduling scheme of a NAN terminal. 12 and 13, it is assumed that the first NAN terminal (hereinafter referred to as 'NAN_1') and the second NAN terminal (hereinafter referred to as 'NAN_2') belong to the same NAN cluster. Further, it is assumed that both the first time axis t1 corresponding to NAN_1 and the second time axis t2 corresponding to NAN_2 have the same time unit TU.

FIG. 12 illustrates a synchronization NDL (S-NDL) scheme among NDL scheduling techniques of a NAN terminal. Referring to FIGS. 11 and 12, the first intervals T0 to T1 of FIG. ) May correspond to the first search window DW_1 or the second search window DW_2 of FIG. 11, and the second sections T1 to T3 of FIG. 12 may correspond to the search window interval DW interval of FIG. 11. .

In step S1210, NAN_2 transmits a subscribe frame to NAN_1. The subscription frame may include information about a supportable service of NAN_2 and a supportable scheduling technique of NAN_2. In step S1220, NAN_1 transmits a publish frame to NAN_2. The publish frame may include information about supportable services of NAN_1 and supportable scheduling of NAN_1.

Through the above steps S1210 and S1220, NAN_1 and NAN_2 may recognize a mutually supportable service and a supporting scheduling technique. Steps S1210 and S1220 are referred to herein as capability exchange steps.

In step S1230, NAN_2 may transmit a data request frame for requesting data to be transmitted to NAN_2 to NAN_1. In step S1240, NAN_1 may transmit a data response frame to NAN_2 in response to a data request frame. In FIG. 12, the data request frame is shown to be transmitted within the first periods T0 to T1, but the present invention is not limited thereto.

Through the above steps S1230 and S1240, NAN_1 and NAN_2 can negotiate a common resource block (CRB) that can transmit and receive data with each other.

In step S1250, NAN_1 may transmit data for NAN_2 to NAN_2. In detail, the NAN_1 and the NAN_2 may enter the common sections T2_1 to T2_2 at the same timing T2_1 to transmit or receive data. In FIG. 12, only one common section T2_1 to T2_2 is illustrated, but it is not limited thereto, and it will be understood that a plurality of common sections CRB may exist in the second section T1 to T3.

FIG. 13 illustrates a paging NDL (P-NDL) technique among NDL scheduling techniques of a NAN terminal. 11 and 13, the first section T0 to T1 correspond to the first search window DW_1 or the second search window DW_2, and the second section T1 to T3 correspond to the search window interval ( DW interval).

In step S1310, NAN_2 transmits a subscription frame to NAN_1. The subscription frame may include information about a supportable service of NAN_2 and a supportable scheduling scheme of NAN_2.

In step S1320, NAN_1 transmits a publish frame to NAN_2. The publish frame may include information about a supportable service of NAN_1 and a supportable scheduling scheme of NAN_1.

Through the above steps S1310 and S1320, NAN_1 and NAN_2 can recognize a mutually supportable service. Steps S1310 and S1320 are referred to herein as capability exchange steps.

In step S1330, to request data to be transmitted to NAN_2, NAN_2 may transmit a data request frame to NAN_1. In operation S1340, NAN_1 may transmit a data response frame to NAN_2 in response to a data request frame. In FIG. 13, the data request frame is shown to be transmitted within the first periods T0 to T1, but is not limited thereto.

Through the above steps S1330 and S1340, NAN_1 and NAN_2 can negotiate a common resource block (CRB) that can transmit and receive data with each other.

The common periods T2_1 to T2_3 of the paging scheme of FIG. 13 include a paging window T2_1 to T2_2 for paging transmission, a paging window PW, and a transmission window T2_2 to T2_3 for transmission of data, TxW. Can be. NAN_1 and NAN_2 enter common sections T2_1 to T2_3 at the same timing T2_1.

In operation S1350, when a predetermined offset time elapses from the same timing T2_1, the NAN_2 may transmit a paging frame to the NAN_1.

In operation S1360, the NAN_1 receiving the paging frame may transmit data for the NAN_2 to the NAN_2 during the transmission windows T2_2 to T2_3 and TxW.

In addition, NAN_1 and NAN_2 of FIGS. 12 and 13 may enter a further available window (FAW) at the same timing T0. In this case, the additional use window FAW may be maintained for the additional periods T0 to T3.

In FIG. 13, only one common section T2_1 to T2_3 is illustrated, but it is not limited thereto, and it will be understood that a plurality of common sections CRB may exist in the second section T1 to T3.

12 and 13 described above are described as operating based on a 2-way scheme for setting up a data path between NAN_1 and NAN_2, but the present disclosure is not limited to this embodiment. As another embodiment, it will be appreciated that a 3-way scheme in which NAN_2 sends a data confirm frame to NAN_1 after receiving a data response frame may be used.

14 and 15 illustrate a conceptual diagram of a scheduling technique of a NAN terminal according to an embodiment of the present disclosure. For the sake of brevity, it is assumed that NAN_1 and NAN_2 in FIGS. 14 and 15 belong to the same NAN cluster. Further, it is assumed that both the first time axis t1 corresponding to NAN_1 and the second time axis t2 corresponding to NAN_2 have the same time unit TU.

14 and 15 correspond to the first search window DW_1 or the second search window DW_2 of FIG. 11, and the second sections T1 to T3 of FIGS. 14 and 15. ) May correspond to the search window interval (DW interval) of FIG. 11. For the sake of brevity of FIGS. 14 and 15, it is assumed that NAN_1 and NAN_2 support both the S-NDL technique and the P-NDL technique.

FIG. 14 shows a case in which NAN_2 selects an S-NDL scheme among supported scheduling schemes of NAN_1. 12 and 14, in step S1410, NAN_2 may transmit a subscribe frame to NAN_1. The subscription frame of FIG. 14 may include a scheduling identifier of NAN_2. For example, the scheduling identifier of NAN_2 may indicate whether the NAN_2 supportable scheduling scheme is S-NDL, P-NDL, or both S-NDL and P-NDL schemes.

As mentioned above, since NAN_2 of FIG. 14 supports both the S-NDL and P-NDL schemes, a scheduling identifier indicating that both the S-NDL and P-NDL schemes can be supported may be included in the subscription frame. . Accordingly, the NAN_1 receiving the subscription frame can recognize a supportable scheduling scheme of the NAN_2.

In step S1420, NAN_1 may transmit a publish frame to NAN_2. The publish frame of FIG. 14 may include a scheduling identifier of NAN_1. For example, the scheduling identifier of NAN_1 may indicate whether the supportable scheduling scheme of NAN_1 is S-NDL, P-NDL, or both S-NDL and P-NDL schemes.

In addition, NAN_1 may include traffic information of a traffic that NAN_1 intends to transmit to NAN_2 in a publish frame. Traffic information that NAN_1 intends to transmit to NAN_2 may mean a TSPEC element (traffic specification element) disclosed in IEEE 802.11 6.2.26.3.2.

In the present specification, step S1410 and step S1420 may be referred to as a capability exchange step. In addition, since NAN_1 of FIG. 14 is assumed to support both the S-NDL and P-NDL schemes, a scheduling identifier indicating that both the S-NDL and P-NDL schemes can be supported is included in the publish frame. Accordingly, the NAN_2 receiving the publish frame can recognize a supporting scheduling scheme of the NAN_1.

In operation S1430, the NAN_2 may select a suitable scheduling scheme based on the published frame received from the received NAN_1. In addition, the content associated with the selection of a suitable scheduling technique is described in detail based on the drawings to be described below.

In step S1440. NAN_2 may transmit a data request frame from NAN_1 to NAN_1 for NAN_2. For example, a data request frame is a frame for requesting data that is currently pending.

The data request frame may include information associated with the TSPEC signaled from NAN_1 in step S1420. In addition, the data request frame may include information about the scheduling scheme selected in step S1430.

For example, primitives for generating a data request frame according to an embodiment are shown in Table 2 below.

With Data Method (handle, configuration_parameters, upper_layer_info) With this Method a service / application in a subscriber requests the NAN Data Engine to transmit a Data Request message to a publisher. Parameters of the method are as follows:-handleA subscribe_id which has been originally returned by an instance of the Subscribe function associated with the data communication-configuration_parameters · Publisher's NAN Interface Address; Publisher's MAC interface address for general NAN operations · Requestor Instance ID ; Identifier of the instance of the Publish function in the publisher, which the data communication setup operation targets at · NAN Data Security; Need Security (1) or No Security (0); Security Policies · Data Schedule; NDC base Schedule bitmap which is 4 byte (8,16, 31 or 62 byte) length.Current NDL Schedule bitmap which is 4 byte (8,16, 31 or 62 byte) length. ; Request NDL Schedule bitmap which is 4 byte (8,16, 31 or 62 byte) length · Data Scheduling Method Option; S-NDL, P-NDL or Both - upper_layer_info · Sequence of values which are to be transmitted in the frame body ; Such as session ID

      In step S1450, NAN_1 may transmit a data response frame for NAN_2 to NAN_2 in response to a data request frame. For example, primitives for generating a data response frame according to the present embodiment are shown in Table 3 below.

DataResponse (handle, configuration_parameters, upper_layer_info) With this Method a service / application in a publisher requests the NAN Data Engine to transmit a Data Response message to a subscriber. Parameters of the method are as follows: - handle · A publish_id which has been originally returned by an instance of the Publish function associated with the data communication - configuration_parameters · Subscriber's NAN Interface Address; Subscriber's MAC interface address for general NAN operations · Requestor Instance ID ; Identifier of the instance of the Subscriber function in the subscriber, which the data communication setup operation originated from · Subscriber's Data Interface Address; Subscriber's MAC interface address for data · NAN Data Security; Need Security or No Security; Security Policies · Data Schedule; NDC base Schedule bitmap which is 4 byte (8,16, 31 or 62 byte) length; Current NDL Schedule bitmap which is 4 byte (8,16, 31 or 62 byte) length; Accepted NDL Schedule bitmap which is 4 byte (8 , 16, 31 or 62 byte) length · Data Scheduling Method Option; S-NDL, P-NDL, Both · Data Setup Status; Accepted or Reason Code - upper_layer_info · Sequence of values which are to b e transmitted in the frame body; Such as session ID, protocol, port number etc.

Through the above steps S1440 and S1450, NAN_1 and NAN_2 can negotiate a common resource block (CRB) that can transmit and receive data with each other.

In operation S1460, the NAN_1 may transmit data for the NAN_2 to the NAN_2 during the common periods T2_1 to T2_2. NAN_1 and NAN_2 may transmit or receive data during common periods T2_1 to T2_2.

In FIG. 14, only one common section T2_1 to T2_2 is illustrated, but it is not limited thereto, and it will be understood that a plurality of common sections CRB may exist in the second section T1 to T3.

If the first period T0 to T1 of FIG. 14 is for further service discovery, the subscription frame and the publish frame may be follw-up. In addition, the subscribe frame and the publish frame may be a GAS frame method. Further service discovery and GAS frames are described in Appendix I of the Wi-Fi Neighbor Awareness Networking (NAN) Technical Specification Version 5.001.0 r19.

FIG. 15 shows a case in which NAN_2 selects a P-NDL scheme among supported scheduling schemes of NAN_1. 13 and 15, in step S1510, NAN_2 may transmit a subscribe frame to NAN_1.

The subscribe frame of FIG. 15 may include a scheduling identifier of NAN_2. For example, the scheduling identifier of NAN_2 may indicate whether the NAN_2 supportable scheduling scheme is S-NDL, P-NDL, or both S-NDL and P-NDL schemes.

As mentioned above, since NAN_2 of FIG. 15 supports both the S-NDL and P-NDL schemes, a scheduling identifier indicating that both the S-NDL and P-NDL schemes can be supported is included in the subscription frame. Subsequently, the NAN_1 receiving the subscription frame may recognize a supportable scheduling scheme of NAN_2.

In step S1520, NAN_1 may transmit a publish frame to NAN_2. The publish frame of FIG. 15 may include a scheduling identifier of NAN_1. NAN_1 may include traffic information of a traffic to be transmitted to NAN_2 in a publish frame and transmit the same to NAN_2. For example, the traffic information may include a TSPEC element.

For example, the scheduling identifier of NAN_1 may indicate whether the supportable scheduling scheme of NAN_1 is S-NDL, P-NDL, or both S-NDL and P-NDL schemes. In this case, since NAN_1 of FIG. 15 is assumed to support both the S-NDL and P-NDL schemes, a scheduling identifier indicating that both the S-NDL and P-NDL schemes can be supported may be included in the subscription frame.

In step S1530, NAN_2 may select a suitable scheduling scheme based on the publish frame received from NAN_1. The contents associated with the selection of the scheduling scheme are described in detail based on the drawings to be described below.

In step S1540, NAN_2 may transmit a data request frame to NAN_1. For example, the data request frame may be a frame requesting data to be delivered to NAN_1.

The data request frame may include information associated with the TSPEC signaled from NAN_1 in step S1520. The data request frame may include information about the scheduling scheme selected in step S1530.

In operation S1550, the NAN_1 may transmit a data response frame to the NAN_2 in response to the data request frame. In FIG. 15, the data request frame is shown to be transmitted within the first periods T0 to T1, but is not limited thereto.

Through the above steps S1540 and S1550, NAN_1 and NAN_2 can negotiate a common resource block (CRB) that can transmit and receive data with each other.

The common periods T2_1 to T2_3 of the paging scheme of FIG. 15 may include a paging window T2_1 to T2_2 for paging transmission and a data transmission period T2_2 to T2_3 for data transmission. NAN_1 and NAN_2 enter common sections T2_1 to T2_3 at the same timing T2_1.

In operation S1560, when a predetermined offset time elapses from the same timing T2_1, the NAN_2 may transmit a paging frame to the NAN_1.

In operation S1570, the NAN_1 receiving the paging frame may transmit data for the NAN_2 to the NAN_2 during the transmission windows T2_2 to T2_3 and TxW.

NAN terminals in a NAN cluster according to the present disclosure may recognize a scheduling scheme that can be supported by each other through a capability exchange process between NAN terminals. In addition, the NAN terminals may select one of the recognized scheduling schemes to form an appropriate NDL between the NAN terminals. Accordingly, communication efficiency between NAN terminals can be increased.

16 is a flowchart illustrating a scheduling method of a data link of a NAN terminal according to an embodiment of the present specification. 14 to 16, in step S1610, a pair of NAN terminals (eg, NAN_1 and NAN_2) may exchange frames including a scheduling identifier associated with an available scheduling scheme of each terminal.

A pair of NAN terminals can recognize a scheduling scheme that can be supported by each other through capability exchange between terminals. In addition, a NAN terminal (eg, NAN_1) that wants to transmit traffic to a counterpart NAN terminal among a pair of NAN terminals may transmit a frame including information related to traffic characteristics (eg, TSPEC element) to the counterpart NAN terminal. For example, the publish frame of FIGS. 14 and 15 may include traffic information (eg, TSPEC element) of traffic for NAN_2.

In step S1620, the pair of NAN terminals may determine whether each NAN terminal supports both S-NDL and P-NDL. If a pair of NAN terminals support both S-NDL and P-NDL, the procedure proceeds to step S1630.

On the contrary, if any one of the pair of NAN terminals supports only one of the S-NDL and the P-NDL, the procedure proceeds to step S1640.

In step S1630, the NAN terminal (for example, NAN_2) of the pair of NAN terminals to receive the traffic information (for example, TSPEC element) received in step S1610 from the NAN terminal (for example, NAN_1) to transmit traffic Based on the scheduling scheme can be selected.

The TSPEC element may include parameters associated with QoS. For example, if the traffic characteristic is not sensitive to delay, P-NDL may be selected. Conversely, S-NDL may be selected if the traffic characteristics are sensitive to delay.

However, the scheduling method of the present specification is not limited to the above contents, and it will be understood that various methods may exist. Step S1630 is described in more detail with reference to the drawings below.

In operation S1640, the NAN terminal NAN_2 that wants to receive traffic may determine whether there is a matching scheme among supportable scheduling schemes of the NAN terminal NAN_1 having the traffic and its own scheduling scheme. If a common scheduling scheme does not exist among a pair of NAN terminals, the procedure ends. On the contrary, if a common scheduling scheme exists among a pair of NAN terminals, the procedure proceeds to step S1650.

In operation S1650, a common scheduling scheme among the pair of NAN terminals may be selected as a scheduling scheme for data transmission between the pair of NAN terminals. For example, when the scheduling scheme of NAN_1 supports both S-NDL and P-NDL, and the scheduling scheme of NAN_2 supports only S-NDL, S-NDL may be selected as a scheduling scheme for traffic transmission.

17 is a flowchart illustrating specific steps in a scheduling method of a NAN terminal according to an embodiment of the present specification. Hereinafter, referring to FIGS. 14 to 17, a detailed description of step S1630 of FIG. 16 for selecting a scheduling scheme of a NAN terminal is disclosed.

14 to 17, a pair of NAN terminals may recognize a scheduling scheme that can be supported by each other from the capability exchange in step S1620.

In step S1731, NAN_2 may check the traffic information (TSPEC element) of the traffic for NAN_2 based on the publish frame transmitted from NAN_1. For example, NAN_2 may identify a field associated with an access policy among the traffic information. If the access policy is a contention-based EDCA, the procedure proceeds to step S1732.

In step S1732, NAN_2 may select the P-NDL scheme as the schedule scheme. When communication between NAN terminals is performed, the reason why the P-NDL scheme is selected is as follows. Because competition-based EDCA has a backoff procedure, a P-NDL technique, which is relatively less sensitive to delay, may be advantageous. The procedure then proceeds to step S1735.

If the access policy is not a contention-based EDCA, in step S1733, NAN_2 may check whether the access policy is HCCA. If the access policy is not a contention based HCCA (meaning mixed mode), the procedure ends. If the access policy is non-competition based HCCA, the procedure proceeds to step S1734.

In step S1734, NAN_2 may select the S-NDL scheme as the scheduling scheme. The reason why the S-NDL scheme is selected when communication between NAN terminals is performed is as follows. Since non-competition based HCCA does not have a back off procedure, an S-NDL technique that is relatively sensitive to delay may be advantageous. The procedure then proceeds to step S1735.

In step S1735, NAN_2 may generate an NDL type indicator (NTI) according to the scheduling technique selected in step S1732 or S1734.

NAN_2 may generate a request message including an NDL type indicator (NTI). In detail, when the NDL type indicator NTI indicates the S-NDL, the request message may be a data request frame of step S1540 of FIG. 15. When the NDL type indicator NTI indicates the P-NDL, the request message may be a paging frame transmitted in step S1640 of FIG. 16.

NAN_2 may send a request message including traffic information (eg, TSPEC element) to request traffic for NAN_2 from NAN_1.

For example, NAN_2 may allocate an additional area for the NDL type indicator (NTI) to the TSPEC element received from NAN_1. In addition, NAN_2 may transmit an NDL type indicator (NTI) using a reserved area of the TSPEC element. A method for assigning an NDL type indicator (NTI) to an existing TSPEC element is described in more detail using the drawings described below.

18 is a diagram illustrating a field of a TSPEC element according to an embodiment of the present specification. 14 to 18, a new field 1800 of 1 bit for the NDL type indicator NTI among the fields of the TSPEC element may be added.

First, a case where S-NDL is mandatory and P-NDL is optional among scheduling techniques of NAN terminals in a NAN cluster will be described. When NAN data communication is performed using S-NDL, the value of the new field 1800 may be '0'. When NAN data communication is performed using the P-NDL and the S-NDL together, the value of the new field 1800 may be '1'.

Second, the case where both the S-NDL and the P-NDL are optional among the scheduling techniques of the NAN terminals in the NAN cluster will be described. When NAN data communication is performed using S-NDL, the value of the new field 1800 may be '0'. When NAN data communication is performed using the P-NDL, the value of the new field 1800 may be '1'.

19 illustrates a subfield of a TSPEC element according to another embodiment of the present specification. Referring to FIGS. 18 and 19, FIG. 19 shows a subfield of TS info 1810 among the fields of the TSPEC element. 14 to 19, information on an NDL type indicator (NTI) may be signaled using 1 bit of the reserved subfield 1900.

First, a case where S-NDL is mandatory and P-NDL is optional among scheduling techniques of NAN terminals in a NAN cluster will be described.

When NAN data communication is performed using S-NDL, the value of the new field 1900 may be '0'. When NAN data communication is performed using the P-NDL and the S-NDL together, the value of the new field 1900 may be '1'.

Second, the case where both the S-NDL and the P-NDL are optional among the scheduling techniques of the NAN terminals in the NAN cluster will be described. When NAN data communication is performed using S-NDL, the value of the new field 1900 may be '0'. When NAN data communication is performed using the P-NDL, the value of the new field 1900 may be '1'.

20 is a block diagram illustrating a wireless device in which an embodiment of the present specification can be implemented.

The wireless device 2000 includes a processor 2010, a memory 2020, and a transceiver 2030. The wireless device may be a NAN terminal in the above embodiment. The transceiver 2030 is connected to the processor 2010 to transmit and / or receive a radio signal.

The processor 2010 implements the functions, processes, and / or methods proposed herein. According to the above-described embodiment, the operation of the NAN terminal may be implemented by the processor 2010.

       The memory 2020 may be connected to the processor 2010 to store an instruction for implementing an operation of the processor 2010.

The processor may include application-specific integrated circuits (ASICs), other chipsets, logic circuits, and / or data processing devices. The memory may include read-only memory (ROM), random access memory (RAM), flash memory, memory card, storage medium and / or other storage device. The RF unit may include a baseband circuit for processing a radio signal.

When an embodiment of the present specification is implemented in software, the above-described technique may be implemented as a module (process, function, etc.) that performs the above-described function. The module may be stored in memory and executed by a processor. The memory may be internal or external to the processor and may be coupled to the processor by various well known means.

In the detailed description of the present specification, specific embodiments have been described.

Various modifications are possible without departing from the scope of the present specification. Therefore, the scope of the present specification should not be limited to the above-described embodiments, but should be determined not only by the claims below but also by the equivalents of the claims of the present invention.

Claims (10)

1. A scheduling method for a data link performed by a first device belonging to a neighbor aware network (NAN),

   Transmitting a first search frame including first scheduling information indicating a scheduling scheme supported by the first device to a second device in a discovery period DW;

   A second discovery frame including second scheduling information indicating a scheduling scheme supported by the second device and traffic information of traffic to be transmitted from the second device to the first device, in the discovery period; Receiving from; And

   If the second scheduling information indicates both a synchronization scheme and a paging scheme, the first device includes selecting one of the synchronization scheme and the paging scheme based on the traffic information; But

   The synchronization technique is a technique in which the first device and the second device enter the data section for the traffic at the same time when the search period ends, and

   The paging scheme is a technique in which the first device transmits a paging message to the second device for receiving the traffic when a predetermined offset time elapses after the search interval ends.
2. The method of claim 1,

   Wherein the search interval is associated with a time and channel at which the first device and the second device converge, and the first device and the second device share a common control parameter.
3. The method of claim 2,

   The control parameter includes information associated with a duration of the search period, information associated with an interval between the search period and a search period of the next cycle, and information associated with a channel used for the NAN. .
4. The method of claim 1,

   And forming the data link for the traffic between the first device and the second device based on the selected technique.
5. The method of claim 1,

   The first search frame and the second search frame is a GAS frame that can be transmitted regardless of whether the search period.
6. The method of claim 1,

   The search interval is an interval for a further available window (FAW) that is further allocated for transmission of the traffic.
7. The method of claim 1,

   Selecting one of the synchronization scheme and the paging scheme based on the traffic information,

   Selecting one of the synchronization scheme and the paging scheme based on quality of service (QoS) information regarding the transmission priority of the traffic.
8. The method of claim 1,

   Sending, by the first device, a request frame requesting transmission of the traffic to the second device,

   The request frame includes information regarding the selected technique.
9. A device using a scheduling method for a data link of a neighbor aware network (NAN),

   A transceiver for transmitting and receiving a radio signal; And

   A processor coupled to the transceiver, wherein the processor includes:

   Control the transceiver to transmit a first search frame including first scheduling information indicating a supportable scheduling scheme of the device to a second device in a discovery interval,

   Receive a second discovery frame from the second device in the discovery period, the second discovery frame including second scheduling information indicating supportable scheduling scheme of the second device and traffic information of traffic to be transmitted from the second device to the device To control the transceiver,

   If the second scheduling information indicates both a synchronization scheme and a paging scheme, select one of the synchronization scheme and the paging scheme based on the traffic information.

   The synchronization scheme is a method in which the device and the second device enter the data section for the traffic at the same time after the search section is finished,

   The paging scheme is a device for transmitting a paging message to the second device to receive the traffic, if a predetermined offset time has elapsed after the search interval ends.
10. The method of claim 9,

    And the processor controls to form the data link with the second device for transmission of the traffic based on the selected technique.

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