KR20150065155A - Method for allocating channel in wireless local area network and apparatus for the same - Google Patents

Abstract

Disclosed are a method and an apparatus for allocating channels in a wireless local area network (LAN). The method includes the steps of: receiving a first frame, including scheduling information about a first interval, from a second access point; generating a second frame, including information related to resources required for transmission and reception through a second interval consecutive with the first interval; and transmitting the second frame to the second access point. Accordingly, performance of the LAN can be enhanced.

Description

TECHNICAL FIELD [0001] The present invention relates to a method and an apparatus for assigning channels in a wireless local area network (WLAN)

The present invention relates to wireless LAN technology, and more particularly, to a channel allocation technique in an overlapping basic service set (OBSS).

With the development of information and communication technology, various wireless communication technologies are being developed. Among them, a wireless local area network (WLAN) may be a personal digital assistant (PDA), a laptop computer, a portable multimedia player (PMP), a smart phone A smart phone, a tablet PC, or the like, to wirelessly connect to the Internet in a home, an enterprise, or a specific service providing area.

The standard for wireless LAN technology is being developed as the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard. The wireless LAN technology according to the IEEE 802.11a standard operates based on an orthogonal frequency division multiplexing (OFDM) scheme and can provide a transmission speed of up to 54 Mbps in the 5 GHz band. The wireless LAN technology according to the IEEE 802.11b standard operates based on a direct sequence spread spectrum (DSSS) scheme and can provide a transmission speed of up to 11 Mbps in the 2.4 GHz band. The wireless LAN technology according to the IEEE 802.11g standard operates based on the OFDM scheme or the DSSS scheme, and can provide a transmission speed of up to 54 Mbps in the 2.4 GHz band.

The wireless LAN technology according to the IEEE 802.11n standard operates in the 2.4 GHz band and the 5 GHz band based on the OFDM scheme. When using the multiple input multiple output (OFDM) and OFDM (MIMO-OFDM) spatial stream) at a transmission rate of up to 300 Mbps. According to the IEEE 802.11n standard, the wireless LAN technology can support a channel bandwidth of up to 40 MHz, which in this case can provide a transmission speed of up to 600 Mbps.

As the spread of the WLAN is activated and the applications using the WLAN are activated, a need for a new WLAN technology to support a higher throughput than the data processing speed supported by IEEE 802.11n is increasing. Very high throughput (VHT) Wireless LAN technology is one of the proposed IEEE 802.11 wireless LAN technologies to support data rates of more than 1 Gbps. Among them, IEEE 802.11ac is being developed as a standard for providing ultra high throughput in a band below 5 GHz, and IEEE 802.11ad is being developed as a standard for providing ultra high throughput in the 60 GHz band.

Recently, as the use of a wireless LAN increases, the possibility of using an overlap channel between a neighbor access point (or a neighboring BSS (basic service set)) is increasing. There is a problem that the performance of the WLAN is deteriorated because the overlapping channel is used between the neighboring BSSs.

In order to solve the above problems, an object of the present invention is to provide a method of allocating channels in consideration of overlapping channels between neighboring BSSs.

Another object of the present invention is to provide an apparatus for allocating a channel in consideration of a superposed channel between neighboring BSSs.

According to another aspect of the present invention, there is provided a channel setting method performed in a first access point, the method comprising: receiving a first frame including a scheduling information for a first interval from a second access point; Generating a second frame including resource related information required for transmission and reception through one interval and a second interval that is successive, and transmitting the second frame to the second access point.

Here, the first frame may be a beacon frame.

Here, the first frame may include duration information indicating a transmission start time of the first frame to a transmission end time of the second frame.

Here, the first frame may include limited connection window information indicating a transmission interval of the second frame.

Here, the first frame may be received at the beginning of the first interval.

Here, the scheduling information may include at least one of an operation channel and a transmission interval of the first access point during the first interval.

Here, the resource-related information includes at least one of expected duration information required for frame transmission / reception through the second interval, a data rate in the first interval previous interval, and a transmission failure rate in bandwidth in the first interval previous interval .

Wherein transmitting the second frame to the second access point may transmit the second frame to the second access point if a poll frame is received from the second access point.

Here, the channel setting method may further include transmitting and receiving a frame with at least one terminal connected to the first access point within an operation channel and a transmission interval indicated by the scheduling information.

According to another aspect of the present invention, there is provided a channel management method performed in a second access point, comprising: generating a first frame including scheduling information for a first interval; Receiving from the first access point a second frame including the resource related information required for transmission and reception via the second interval following the first interval; and transmitting the second frame to the access point.

Here, the first frame may be a resource allocation frame.

Here, the first frame may be transmitted to the first access point after the beacon frame of the second access point is transmitted.

Here, the scheduling information may include at least one of an operation channel and a transmission interval of the first access point during the first interval.

Here, the resource-related information includes at least one of expected duration information required for frame transmission / reception through the second interval, a data rate in the first interval previous interval, and a transmission failure rate in bandwidth in the first interval previous interval .

Here, the channel management method may further include generating scheduling information for the second interval based on the resource-related information.

According to another aspect of the present invention, there is provided a first access point comprising a processor and a memory in which at least one instruction executed through the processor is stored, Comprising: receiving a first frame including scheduling information for a first interval from a first interval, generating a second frame including resource related information required for transmission and reception through a second interval following the first interval, And transmitting the second frame to the second access point.

Here, the scheduling information may include at least one of an operation channel and a transmission interval of the first access point during the first interval.

Here, the resource-related information includes at least one of expected duration information required for frame transmission / reception through the second interval, a data rate in the first interval previous interval, and a transmission failure rate in bandwidth in the first interval previous interval .

Wherein transmitting the second frame to the second access point may transmit the second frame to the second access point when a resource allocation frame is received from the second access point.

The at least one command may be operable to further perform transmitting and receiving frames with at least one terminal connected to the first access point within an operation channel and a transmission interval indicated by the scheduling information.

According to the present invention, the performance of the wireless LAN can be improved.

1 is a block diagram illustrating one embodiment of a station performing methods in accordance with the present invention.
2 is a conceptual diagram showing an embodiment of a configuration of a wireless LAN system according to IEEE 802.11.
3 is a conceptual diagram showing the OBSS.
4 is a conceptual diagram for explaining a method of allocating non-overlapping channels to BSSs.
5 is a conceptual diagram for explaining a coordination method for a transmission interval when the same channel is allocated to BSSs.
6 is a conceptual diagram for explaining a channel wasted in a conventional wireless LAN.
FIG. 7 is a conceptual diagram showing an embodiment of a method of performing coordination for an overlapping channel. FIG.
8 is a conceptual diagram illustrating a channel allocation method according to an embodiment of the present invention.
9 is a conceptual diagram illustrating a channel allocation method according to another embodiment of the present invention.
10 is a conceptual diagram illustrating an embodiment of a resource allocation element.
11 is a block diagram illustrating an embodiment of a resource allocation feedback frame.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail.

It should be understood, however, that the invention is not intended to be limited to the particular embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

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

It is to be understood that when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, . On the other hand, when an element is referred to as being "directly connected" or "directly connected" to another element, it should be understood that there are no other elements in between.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the terms "comprises" or "having" and the like are used to specify that there is a feature, a number, a step, an operation, an element, a component or a combination thereof described in the specification, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the relevant art and are to be interpreted in an ideal or overly formal sense unless explicitly defined in the present application Do not.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In order to facilitate the understanding of the present invention, the same reference numerals are used for the same constituent elements in the drawings and redundant explanations for the same constituent elements are omitted.

Throughout the specification, a station is a physical layer for medium access control (MAC) and a medium access control (MAC) compliant with the IEEE 802.11 standard. Means any functional medium including an interface. A station (STA) can be divided into a station (STA) which is an access point (AP) and a station (STA) which is a non-AP. A station (STA), which is an access point (AP), may be referred to simply as an access point (AP), and a station (STA) that is a non-AP may be simply referred to as a terminal.

The station STA may include a processor and a transceiver, and may further include a user interface and a display device. A processor is a unit designed to generate a frame to be transmitted through a wireless network or to process a frame received through a wireless network, and may perform various functions for controlling the station (STA). A transceiver is a unit that is functionally connected to a processor and is designed to transmit and receive frames over a wireless network for a station (STA).

An access point (AP) includes a centralized controller, a base station (BS), a radio access station, a node B, an evolved node B, a relay, a multihop relay-BS, a base transceiver system (BTS), a site controller, and the like, and may include some or all of their functions.

A terminal (i.e., a non-access point) may comprise a wireless transmit / receive unit (WTRU), user equipment (UE), a user terminal (UT), an access terminal Refers to a mobile station (MS), a mobile terminal, a subscriber unit, a subscriber station (SS), a wireless device, or a mobile subscriber unit And may include some or all of their functions.

The terminal may be a desktop computer, a laptop computer, a tablet PC, a wireless phone, a mobile phone, a smart phone, a smart watch, such as a smart watch, a smart glass, an e-book reader, a portable multimedia player (PMP), a portable game machine, a navigation device, a digital camera, a digital multimedia broadcasting (DMB) A digital audio recorder, a digital audio player, a digital picture recorder, a digital picture player, a digital video recorder, a digital video player ) And the like.

1 is a block diagram illustrating one embodiment of a station performing methods in accordance with the present invention.

Referring to FIG. 1, a station 100 may include at least one processor 110, a memory 120, and a network interface device 130 for communicating with a network. In addition, the station 100 may further include an input interface device 140, an output interface device 150, a storage device 160, and the like. Each component included in the station 100 may be connected by a bus 170 and communicate with each other.

The processor 110 may execute a program command stored in the memory 120 and / or the storage device 160. The processor 110 may refer to a central processing unit (CPU), a graphics processing unit (GPU), or a dedicated processor on which the methods of the present invention are performed. The memory 120 and the storage device 160 may be composed of a volatile storage medium and / or a non-volatile storage medium. For example, memory 120 may be comprised of read only memory (ROM) and / or random access memory (RAM).

The embodiments of the present invention are applied to a wireless LAN system according to IEEE 802.11, and can be applied to other communication systems as well as a wireless LAN system according to IEEE 802.11.

For example, embodiments of the present invention may be implemented in a portable Internet such as a wireless personal area network (WPAN), a wireless body area network (WBAN), a wireless broadband internet (WiBro) or a world interoperability for microwave access (WiMax) a 3G mobile communication network such as wideband code division multiple access (WCDMA) or cdma2000, a high speed downlink packet access (HSDPA) or a high speed uplink (HSUPA) a 3.5G mobile communication network such as a packet access, a 4G mobile communication network such as LTE (Long Term Evolution) or LTE-Advanced, and a 5G mobile communication network.

2 is a conceptual diagram showing an embodiment of a configuration of a wireless LAN system according to IEEE 802.11.

Referring to FIG. 2, a wireless LAN system according to IEEE 802.11 may include at least one basic service set (BSS). BSS means a set of stations (STA1, STA2 (AP1), STA3, STA4, STA5 (AP2), STA6, STA7, STA8) that can successfully communicate with each other and communicate with each other, .

The BSS can be divided into an infrastructure BSS (infrastructure BSS) and an independent BSS (IBSS). Here, BSS1 and BSS2 denote an infrastructure BSS, and BSS3 denotes an IBSS.

The BSS1 is a distribution system for connecting a first terminal STA1, a first access point STA2 (AP1) providing a distribution service and a plurality of access points STA2 (AP1), STA5 (AP2) distribution system, DS). In the BSS1, the first access point STA2 (AP1) can manage the first terminal STA1.

The BSS2 connects the third terminal STA3, the fourth terminal STA4, the second access point STA5 (AP2) providing the distribution service and the plurality of access points STA2 (AP1) and STA5 (AP2) And a distribution system (DS). The second access point STA5 (AP2) in the BSS2 can manage the third terminal STA3 and the fourth terminal STA4.

BSS3 means an IBSS operating in an ad-hoc mode. In BSS3, there is no access point which is a centralized management entity. That is, the terminals STA6, STA7, and STA8 in the BSS3 are managed in a distributed manner. In the BSS 3, all the terminals STA6, STA7, and STA8 may denote a mobile terminal and form a self-contained network since the connection is not permitted to the distribution system DS.

The access points STA2 (AP1) and STA5 (AP2) can provide a connection to the distributed system DS via the wireless medium for the terminals STA1, STA3 and STA4 coupled thereto. The communication between the terminals STA1, STA3 and STA4 in the BSS1 or BSS2 is generally performed through the access points STA2 and STA5 and when the direct link is established, STA1, STA3, STA4) is possible.

A plurality of infrastructure BSSs may be interconnected via a distribution system (DS). A plurality of BSSs connected through a distribution system (DS) is referred to as an extended service set (ESS). (STA1, STA3, and STA4) in the same ESS can communicate with each other without interrupting the communication between the terminals (STA1, STA2, APA, STA3, STA4, From the BSS to another BSS.

The distribution system DS is a mechanism by which one access point communicates with another access point, whereby the access point transmits a frame for terminals coupled to the BSS it manages, or moves to another BSS A frame can be transmitted for an arbitrary terminal. The access point can also transmit and receive frames to and from an external network, such as a wired network. Such a distribution system (DS) does not necessarily have to be a network, and there is no restriction on the form if it can provide a predetermined distribution service defined in the IEEE 802.11 standard. For example, the distribution system may be a wireless network, such as a mesh network, or may be a physical structure that connects the access points to each other.

Recently, the use of wireless LANs has been rapidly increased, and the problem caused by OBSS (overlapping BSS) has become serious. A collision between BSSs due to overlapping of BSSs in an area where access points are concentrated, a competition of channel access between stations, and the like may deteriorate the performance of the WLAN. In particular, more collisions occur between BSSs using the same channel, and different channels may be allocated to neighboring BSSs to prevent such collisions. When a different channel is allocated to neighboring BSSs, collision does not occur between neighboring BSSs, and stations belonging to neighboring BSSs can perform transmission and reception independently of each other. For this purpose, when the access point establishes a new BSS, it must set its own BSS channel so that it does not overlap the channels of the neighboring BSSs. In addition, the access point must change its own channel as needed when interference is caused by the BSS newly established by the neighboring access point.

Although the number of channels that can be used in a wireless LAN is limited, the number of access points is rapidly increasing. Therefore, it is not easy for a neighboring access point to allocate a channel to use a channel that does not overlap with each other. In fact, the channels may overlap between neighboring access points, in which case the simultaneous transmission probabilities of neighboring access points may vary depending on which channel is assigned to each of the neighboring access points and which channel is set as the primary channel It can be different. In particular, when a narrow band is allocated to allow simultaneous transmission of stations in neighboring BSSs, the performance of the WLAN can be improved by simultaneous transmission over narrow bands.

If overlapping channels are used between neighboring BSSs, resource utilization can be improved if resources are allocated such that transmissions over narrow bands are performed within the same time period. According to the IEEE 802.11 standard, a station can transmit a frame by accessing a channel through contention in a distributed manner. In such an environment, it is impossible to schedule the resources so that transmission over the narrow band is performed within the same time interval.

Hereinafter, a method of allocating channels in consideration of overlapping channels between neighboring BSSs will be described in detail.

3 is a conceptual diagram showing the OBSS.

3, a first access point AP1 can set BSS1, a second access point AP2 can set BSS2, a third access point AP3 can set BSS3, The access point AP4 can set the BSS4, and the fifth access point AP5 can set the BSS5. In the case where the access points AP1, AP2, AP3, AP4 and AP5 use the same channel, a lot of channel access contention and frame collision occur in the overlapped area between the access points AP1, AP2, AP3, AP4 and AP5 . As a result, the performance of the wireless LAN may deteriorate.

The following method can be used to mitigate channel access contention and frame collision.

- Assigning non-overlapping channels to BSSs

- A method of performing coordination so that transmission intervals are not overlapped between BSSs when the same channel is allocated to BSSs

- To allocate non-overlapping channels to BSSs as much as possible, but to perform overlapping channel coordination when overlapping channels are generated due to insufficient number of channels

How to assign non-overlapping channels to BSSs

4 is a conceptual diagram for explaining a method of allocating non-overlapping channels to BSSs.

Referring to FIG. 4, a first access point (AP1) for setting a BSS1 can identify empty channels (CH0 to CH11) through a scanning process. The first access point AP1 may set the BSS1 to operate in CH0 to CH3 among the empty channels CH0 to CH11. The second access point AP2 that desires to set the BSS2 can check the empty channels CH4 to CH11 through the scanning procedure. The second access point AP2 can set the BSS2 to operate in CH4 to CH7 among the empty channels CH4 to CH11. The third access point AP3 which desires to set the BSS3 can confirm the empty channels CH8 to CH11 through the scanning procedure. The third access point AP3 may set the BSS3 to operate on the empty channels CH8 to CH11. Thus, each of the access points AP1, AP2, AP3 can transmit and receive frames without interference by other access points.

On the other hand, a hidden access point may not be detected in the scanning procedure. In this case, each of the access points AP1, AP2, AP3 can set the BSS without confirming the existence of the hidden access point. Each of the access points AP1, AP2, and AP3 is not interfered with transmission / reception of the hidden access point. However, a terminal connected to each of the APs AP1, AP2 and AP3 may be located in the BSS set by the hidden AP. In this case, a terminal connected to each of the access points AP1, AP2 and AP3 may be interfered by transmission / reception of a hidden access point.

When allocating the same channel to BSSs, a method of performing coordination so that transmission intervals are not overlapped among BSSs

If there are not many empty channels and the same channel is allocated to the BSSs, coordination of the transmission interval between the BSSs is required to mitigate channel access contention and frame collision in the BSSs. That is, when a station belonging to each of the BSSs transmits and receives frames at different times, channel access contention and frame collision can be mitigated.

5 is a conceptual diagram for explaining a coordination method for a transmission interval when the same channel is allocated to BSSs.

Referring to FIG. 5, the first access point AP1 to set the BSS1 can identify the empty channels CH0 to CH7 through a scanning procedure. The first access point AP1 may set the BSS1 to operate in CH0 to CH3 of the empty channels CH0 to CH7. The second access point AP2 that wishes to set the BSS2 can check the empty channels CH4 to CH7 through the scanning procedure. The second access point AP2 may set the BSS2 to operate on the empty channels CH4 to CH7.

The third access point AP3 to set the BSS3 can know that all the channels CH0 to CH7 are being used by the other access points AP1 and AP2 through the scanning procedure. In this case, since the third access point AP3 does not have an empty channel, it can set the BSS3 to operate in a channel that another access point is using (for example, CH0 to CH3). The fourth access point AP4 to set the BSS4 can know that all the channels CH0 to CH7 are being used by the other access points AP1, AP2 and AP3 through the scanning procedure. In this case, since the fourth access point AP4 does not have an empty channel, it can set the BSS4 to operate in a channel that another access point is using (e.g., CH4 to CH7).

At this time, the transmission / reception of the station belonging to the BSS1 can be interfered by the station belonging to the BSS3, and conversely, the transmission / reception of the station belonging to the BSS3 can be interfered with by the station belonging to the BSS1. In addition, the transmission / reception of a station belonging to the BSS2 can be interfered by the station belonging to the BSS4, and conversely, the transmission / reception of the station belonging to the BSS4 can be interfered with by the station belonging to the BSS2.

In such an environment, the master access point can set the transmission interval of the first access point AP1 and the transmission interval of the third access point AP3 differently from CH0 to CH3. In addition, the master access point can set the transmission interval of the second access point AP2 and the transmission interval of the fourth access point AP4 differently from CH4 to CH7. Here, one of the access points AP1, AP2, AP3, and AP4 may operate as a master access point, or an access point other than the access points AP1, AP2, AP3, .

On the other hand, an access point having a coordination function can notify itself of its operation as a master access point through a beacon frame or a probe response frame. When an access point that desires to set up a new BSS finds a master access point, it can request the master access point to allocate the best channel considering the operation channels of other BSSs.

The master access point can perform coordination on the operation channel and the transmission interval so as not to collide with other access points when allocating the same channel to the access points or allocating the channel such that some channels other than the primary channel are overlapped . The access point can allocate resources to terminals belonging to its BSS in an operation channel and a transmission interval allocated by the master access point, and transmit / receive frames to / from the terminals through the allocated resources. The master access point may assign a transmission interval to each of the access points within a beacon interval.

If the access points are sufficiently far apart from each other, even if the same channel is used, the access points can transmit frames at the same time. The master access point may obtain interference information for each neighboring access point from each of the access points and may assign the same transmission interval to access points that do not interfere with each other based on the obtained interference information.

To this end, the access point transmits a frame request frame defined in the IEEE 802.11 standard to a terminal connected to the access point and receives a frame response frame, which is a response to the frame request frame, from the terminal, And interference information for a terminal connected to a neighboring access point. In addition, the access point may obtain interference information for a neighboring access point using a beacon request frame / beacon response frame instead of a frame request frame / frame response frame. The access point may transmit the obtained interference information to the master access point. The master access point can perform coordination on the operation channel and the transmission interval based on the interference information obtained from the access point.

Alternatively, the terminal may transmit interference information to at least one of a neighbor access point and a neighboring access point to an access point connected thereto without an exchange procedure of a frame request frame / frame response frame (or a beacon request frame / beacon response frame). The access point may transmit the obtained interference information to the master access point. The master access point can perform coordination on the operation channel and the transmission interval based on the interference information obtained from the access point.

If the master access point exists in the wireless LAN, the channel can be efficiently used through coordination of the operation channel and the transmission interval. However, if there is no master access point, the channel may be wasted as follows.

6 is a conceptual diagram for explaining a channel wasted in a conventional wireless LAN.

Referring to FIG. 6, the first access point AP1 may set the BSS1 to operate at CH0 to CH3 (total of 80 MHz) and set the primary channel to CH0. The second access point AP2 can set the BSS2 to operate at CH1 to CH4 (total 80 MHz) and set the primary channel to CH4.

The first access point AP1 can transmit / receive a frame to / from the terminals belonging to the BSS1 through CH0 to CH3 during T1, and can transmit / receive frames with terminals belonging to the BSS1 via the CH0 to CH1 during the T2. On the other hand, if the terminal belonging to the BSS2 that wants to transmit the frame using the 80MHz bandwidth during the time T2 is far from the first access point AP1, the CH1 to CH4 may be idle on the terminal side. In this case, The CH 2 to CH 4 transmits the RTS frame using the 80 MHz bandwidth and the second access point AP 2 transmits the clear to send (CTS) frame since the CH 1 to CH 4 are not in the idle state due to the transmission of the first access point AP 1. Can not be transmitted to the corresponding terminal. That is, when a terminal belonging to the BSS2 supports dynamic RTS / CTS (clear to send) defined in the IEEE 802.11ac standard, the second access point AP2 transmits a CTS frame through the CH2 to CH4 to the RTS frame However, if the dynamic RTS / CTS is not supported, the second access point AP2 can not transmit the CTS frame to the terminal that transmitted the RTS frame during T2. Therefore, CH2 to CH4 may be wasted during T2.

If the master access point assigns CH0 to CH1 to the first access point AP1 and assigns CH2 to CH4 to the second access point AP2 at T2 and the corresponding channel assignment information is transmitted to the first access point AP1, When notified to the access point AP2 and the terminal connected to the BSS1 and BSS2, the access points AP1 and AP2 can simultaneously transmit and receive frames at T2.

A method of allocating non-overlapping channels to BSSs as much as possible and performing coordination for overlapping channels when overlapping channels are generated due to insufficient number of channels

FIG. 7 is a conceptual diagram showing an embodiment of a method of performing coordination for an overlapping channel. FIG.

Referring to FIG. 7, a first access point (AP1) to set a BSS1 can request channel assignment to a master access point. The master access point can assign CH0 to CH3 (total of 80 MHz) to the first access point AP1 and CH0 to the primary channel of the first access point AP1. The second access point AP2 that wishes to set the BSS2 can request channel assignment to the master access point. The master access point can assign CH1 to CH4 (total of 80 MHz) to the second access point AP2 and CH4 to the primary channel of the second access point AP2. Here, the primary channel of each of the access points AP1 and AP2 may be arranged to be as far as possible. CH1 to CH3 may be assigned to both the first access point AP1 and the second access point AP2.

The master access point can perform coordination on the operation channel and the transmission period so that the first access point AP1 can transmit and receive frames through CH0 to CH3 during T1. The master access point transmits and receives frames through CH0 to CH1 during time T2 and transmits and receives frames through CH3 to CH4 during time T2 so that the second access point AP2 can transmit and receive frames. Can be performed. In this case, the access points AP1 and AP2 can simultaneously transmit and receive frames through the narrow band (CH0 to CH1, CH3 to CH4) during the same transmission period T2. The master access point can perform coordination on the operation channel and the transmission period so that the second access point AP2 can transmit and receive the frame through CH1 to CH4 during T3.

FIG. 8 is a conceptual diagram illustrating a channel allocation method according to an embodiment of the present invention, and FIG. 9 is a conceptual diagram illustrating a channel allocation method according to another embodiment of the present invention.

Referring to FIG. 8 and FIG. 9, a first access point AP1 to set a BSS1 can request a channel assignment to a master access point (M-AP). The master access point (M-AP) can allocate a channel to the first access point (AP1) considering the operation channel of the neighboring access points. For example, the master access point AP1 may assign CH0-CH3 (see FIG. 7) to the first access point AP1 and set CH0 as the primary channel of the first access point AP1 .

 The second access point AP2 that desires to set the BSS2 can request channel assignment to the master access point (M-AP). The master access point (M-AP) can allocate a channel to the second access point (AP2) in consideration of the operation channel of the neighboring access points. For example, the master access point AP2 may assign CH1 to CH4 (see FIG. 7) to the second access point AP2 and CH4 to the primary channel of the second access point AP2 .

Here, the primary channel of the master access point (M-AP) may be set differently from the primary channel of each of the access points AP1 and AP2. The master access point (M-AP) may support a wide band (e.g., 160 MHz) to include the operating channels of the access points AP1, AP2.

The master access point (M-AP) can perform coordination on the operation channel and transmission interval of each of the access points (AP1, AP2) using the resource allocation frame or the beacon frame. The master access point (M-AP) can perform coordination with respect to an operation channel and a transmission interval of each of the access points (AP1, AP2) on an interval basis of a resource allocation frame or an interval of a beacon frame. Here, the master access point (M-AP) assigns CH0 to CH3 to the first access point (AP1) during T1, assigns CH0 to CH1 to the first access point (AP1) during T2, and CH3 to CH4 To the second access point AP2 and assigns CH1 to CH4 to the second access point AP2 during T3.

Resource allocation frame-based coordination

The master access point (M-AP) may transmit the beacon frame 800 periodically in a broadcast manner. The master access point (M-AP) may generate a resource allocation frame (801) for channel coordination for the first access point (AP1) after transmitting the beacon frame. The configuration of the resource allocation element included in the resource allocation frame 801 is as follows.

10 is a conceptual diagram illustrating an embodiment of a resource allocation element.

Referring to FIG. 10, a resource allocation element may include an allocated resource field, an allocation interval field, and an allocation period field. The assigned resource field may include a start time field, a duration field, and a bandwidth field. When one resource allocation element indicates a plurality of transmission intervals, a plurality of allocated resource fields may exist in one resource allocation element. For example, if one resource allocation element represents two different transmission intervals, there may be two allocated resource fields in one resource allocation element.

 The start time field may have a size of 8 bits and may indicate a duration from a transmission time point of a resource allocation frame (or a beacon frame) to a start time point of an allocated transmission interval. The duration field may have a size of 14 bits and may indicate the duration of the allocated transmission interval. The bandwidth field may have a size of 2 bits and may indicate the available bandwidth during the allocated transmission interval. That is, the bandwidth field may indicate the available bandwidth during the allocated transmission interval.

 The allocation interval field may have a size of 16 bits and may indicate a transmission interval of a resource allocation frame (or a beacon frame). The assignment period field may have a size of 8 bits and may be expressed as a multiple of the allocation interval field. The allocation period field may indicate a period in which information included in the allocated resource field of the corresponding resource allocation frame (or beacon frame) is applied. Therefore, a new resource allocation frame (or beacon frame) may not be transmitted during the interval indicated by the allocation period field.

The resource allocation element may further include a beacon interval of a master access point (M-AP), a target beacon transmission time (TBTT), a time stamp, and the like. Here, the beacon interval, TBTT, and time stamp of the master access point can be used for synchronization with the master access point (M-AP).

8 and 9, the resource allocation element of the resource allocation frame 801 may include two allocated resource fields. The first allocated resource field may include a start time field indicating a duration from a transmission time point of the resource allocation frame 801 to a start time point of T1, a duration field indicating a duration of T1, and a bandwidth field indicating CH0 to CH3 . The second allocated resource field may include a start time field indicating a duration from a transmission time point of the resource allocation frame 801 to a start time point of T2, a duration field indicating a duration of T2, and a bandwidth field indicating CH0 to CH1 . In addition, the duration field included in the resource allocation frame 801 is used to guarantee the transmission of the resource allocation feedback frame 802 from the transmission time point of the resource allocation frame 801 to the transmission completion time point of the resource allocation feedback frame 802 Duration can be indicated.

The master access point (M-AP) may transmit the resource allocation frame 801 to the first access point AP1. At this time, the master access point (M-AP) can transmit the resource allocation frame 801 to the first access point AP1 through the primary channel CH0 of the first access point AP1. The first access point AP1 may receive the resource allocation frame 801 from the master access point (M-AP) and may receive the resource allocation element 801 from the CHO- You can see that CH3 is available and CH0 ~ CH1 are available during T2. Also, the first access point AP1 may allocate an interval, a period, a beacon interval of a master access point (M-AP), a TBTT, and a beacon interval of a resource allocation frame 801 based on a resource allocation element included in the resource allocation frame 801, Time stamps and the like can be known.

Thereafter, the first access point (AP1) may generate a resource allocation feedback frame (802). The resource allocation feedback frame 802 may be used to notify the master access point (M-AP) of the resource information required for transmission and reception over the interval according to the next resource allocation frame. The configuration of the resource allocation feedback frame 802 is as follows.

11 is a block diagram illustrating an embodiment of a resource allocation feedback frame.

11, a resource allocation feedback frame includes a frame control field 1100, a duration field 1101, a receiver address field 1102, a transmitter address field 1103, a feedback control field 1104, an estimated UL duration field 1105, an average UL data rate field 1106, an estimated DL duration field 1107, an average DL data rate field 1108, a 20 MHz failure rate field 1109 A 40 MHz failure rate field 1110, an 80 MHz failure rate field 1111, a 160 MHz failure rate field 1112, and a frame check sequence (FCS) field 1113. In addition, the resource allocation feedback frame includes bandwidth information used during the interval according to the previous resource allocation frame (or previous beacon frame), minimum bandwidth required for transmission / reception over the interval according to the next resource allocation frame (or next beacon frame) And may further include information.

The feedback control field 1104 includes a bandwidth field 1104-1, an UL feedback indication field 1104-2, a DL feedback indication field 1104-3, a 20MHz indication field 1104-4, An 80 MHz indication field 1104-6, and a 160 MHz indication field 1104-7.

The bandwidth field 1104-1 may have a size of two bits. The bandwidth field 1104-1 represents the minimum bandwidth required for the next interval (e.g., 20MHz / 40MHz / 80MHz / 160MHz). The 20 MHz indication field 1104-4, the 40 MHz indication field 1104-5, the 80 MHz indication field 1104-6 and the 160 MHz indication field 1104-7 each have a size of 1 bit and are each 20 MHz , 40 MHz, 80 MHz, and 160 MHz, respectively. If this bit is set to '1', it indicates that the transmission was performed in the corresponding bandwidth in the previous transmission. If it is '0', it indicates that the transmission was not performed in the corresponding bandwidth.

 The UL feedback indication field 1104-2 may have a size of one bit and may indicate whether there is an estimated UL duration field 1105 and an average UL data rate field 1106 in the resource allocation feedback frame. If this bit is 1, there is an estimated UL duration field 1105 and an average UL data rate field 1106 in the resource allocation feedback frame, and if it is 0, the estimated UL duration field 1105 and average UL data rate 1105 in the resource allocation feedback frame There is no rate field 1106.

The DL feedback indication field 1104-3 may have a size of 1 bit and may indicate whether there is an estimated DL duration field 1107 and an average DL data rate field 1108 in the resource allocation feedback frame. The DL duration field 1107 and the average DL data rate field 1108 estimated in the resource allocation feedback frame exist and if it is 0, the DL duration field 1107 and the average DL data field 1107 estimated in the resource allocation feedback frame exist, There is no rate field 1108.

If the 20 MHz indication field 1104-4 is 1, there is a 20 MHz failure rate field 1109 in the resource allocation feedback frame. If the 20 MHz indication field 1104-4 is 0, there is no 20 MHz failure rate field 1109 in the resource allocation feedback frame. If the 40MHz indication field 1104-5 is 1, there is a 40MHz failure rate field 1110 in the resource allocation feedback frame, and if it is 0, there is no 40MHz failure rate field 1110 in the resource allocation feedback frame. If the 80MHz indication field 1104-6 is 1, there is an 80MHz failure rate field 1111 in the resource allocation feedback frame, and if it is 0, there is no 80MHz failure rate field 1111 in the resource allocation feedback frame. If the 160MHz indication field 1104-7 is 1, there is a 160MHz failure rate field 1112 in the resource allocation feedback frame, and if it is 0, there is no 160MHz failure rate field 1112 in the resource allocation feedback frame.

The estimated UL duration field 1105 may have a size of two octets and may indicate the expected duration required for the uplink transmission during an interval according to the next resource allocation frame (or beacon frame). The expected duration required for the uplink transmission depends on the data size to be transmitted during the interval according to the next resource allocation frame (or beacon frame) and the average data rate of the uplink transmission during the interval according to the previous resource allocation frame (or beacon frame) . ≪ / RTI > The average UL data rate field 1106 may have a size of two octets and may represent the average data rate of the uplink transmission during the interval according to the previous resource allocation frame (or beacon frame).

The estimated DL duration field 1107 may have a size of one octet and may represent the expected duration required for downlink transmission during an interval according to the next resource allocation frame (or beacon frame). The expected duration required for downlink transmission is the average data rate of the downlink transmission during the interval according to the previous resource allocation frame (or beacon frame) and the data size to be transmitted during the interval according to the next resource allocation frame (or beacon frame) . ≪ / RTI > The average DL data rate field 1108 may have a size of one octet and may represent the average data rate of the downlink transmission during the interval according to the previous resource allocation frame (or beacon frame).

The 20MHz Failure Rate field 1109 may have a size of one octet and may represent a failure rate of transmission over a 20MHz bandwidth during an interval according to a previous resource allocation frame (or beacon frame). The 40 MHz failure rate field 1110 may have a size of one octet and may indicate a failure rate of transmission over a 40 MHz bandwidth during an interval according to a previous resource allocation frame (or beacon frame). The 80 MHz failure rate field 1111 may have a size of one octet and may represent a failure rate of transmission over an 80 MHz bandwidth during an interval according to a previous resource allocation frame (or beacon frame). The 160 MHz failure rate field 1112 may have a size of one octet and may represent a failure rate of transmission over a 160 MHz bandwidth during an interval according to a previous resource allocation frame (or beacon frame). Here, the transmission failure rate can be expressed as '(transmission failure times / transmission attempts times) 255'.

8 and 9, the first access point AP1 may transmit the generated resource allocation feedback frame 802 to the master access point (M-AP). Alternatively, the first access point AP1 transmits a resource allocation feedback frame 802 generated when a poll frame is received from the master access point (M-AP) to the master access point (M-AP) . At this time, in order to protect the transmission of the resource allocation feedback frame 802, the first access point AP1 transmits a resource allocation feedback frame 802 in a non-HT (high throughput) (802) to the master access point (M-AP).

The master access point (M-AP) can receive the resource allocation feedback frame (802) from the first access point (AP1) and, based on the information contained in the received resource allocation feedback frame (802) Can be performed. For example, the master access point (M-AP) determines the expected duration required for the uplink transmission included in the resource allocation feedback frame 802, the expected duration required for the downlink transmission, the average data rate of the uplink transmission , The average data rate of the downlink transmission, and the like, to the first access point AP1.

In addition, the master access point (M-AP) can allocate a bandwidth with a relatively low transmission failure rate to the first access point (AP1) during the interval according to the next resource allocation frame in consideration of the transmission failure rate depending on the bandwidth. For example, if the transmission failure rate below 40 MHz bandwidth is lower than the 80 MHz bandwidth during the interval according to the previous resource allocation frame, the master access point (M-AP) allocates a 40 MHz bandwidth or less for the interval according to the next resource allocation frame to the first access And can be assigned to the point AP1.

When the M-AP has completed receiving the resource allocation feedback frame 802, the M-AP can generate a resource allocation frame 803 for coordination with respect to the operation channel and transmission interval of the second access point AP2 have. The resource allocation element included in the resource allocation frame 803 may be the same as the resource allocation element described with reference to FIG.

That is, the resource allocation element of the resource allocation frame 803 may include two allocated resource fields. The first allocated resource field may include a start time field indicating the duration from the transmission time point of the resource allocation frame 803 to the start time point of T2, a duration field indicating the duration of T2, and a bandwidth field indicating CH3 to CH4 . The second allocated resource field may include a start time field indicating the duration from the transmission time point of the resource allocation frame 803 to the start time point of T3, a duration field indicating the duration of T3, and a bandwidth field indicating CH1 to CH4 . The duration field included in the resource allocation frame 803 is used to guarantee the transmission of the resource allocation feedback frame 804 from the transmission time point of the resource allocation frame 803 to the transmission completion time point of the resource allocation feedback frame 804. [ Duration can be indicated.

The master access point (M-AP) may transmit the resource allocation frame 803 to the second access point AP2. At this time, the master access point (M-AP) can transmit the resource allocation frame 803 to the second access point AP2 through the primary channel CH4 of the second access point AP2. The second access point AP2 may receive the resource allocation frame 803 from the master access point (M-AP) and may receive the resource assignment frame 803 from the CH3- You can see that CH4 is available and CH1 to CH4 are available during T3. Also, the second access point AP2 may allocate the resource allocation frame 803 based on the resource allocation element included in the resource allocation frame 803, such as an interval, a period, a beacon interval of the master access point (M-AP) Time stamps and the like can be known.

Thereafter, the second access point AP2 may generate a resource allocation feedback frame 804. The resource allocation feedback frame 804 may be used to inform the master access point (M-AP) of the resource information required during the interval according to the next resource allocation frame. The resource allocation feedback frame 804 may be the same as the resource allocation feedback frame described above with reference to FIG.

The second access point AP2 may transmit the generated resource allocation feedback frame 804 to the master access point (M-AP). Alternatively, the second access point AP2 may transmit the generated resource allocation feedback frame 804 to the master access point (M-AP) when receiving an arbitrary poll frame from the master access point (M-AP). At this time, to protect the transmission of the resource allocation feedback frame 804, the second access point AP2 transmits a resource allocation feedback frame 804 in the form of a non-HT Duplicate to the master access point 804 through CH1- (M-AP).

The master access point (M-AP) can receive the resource allocation feedback frame (804) from the second access point (AP2) and, based on the information contained in the received resource allocation feedback frame (804) Can be performed. For example, the master access point (M-AP) may determine the expected duration required for the uplink transmission included in the resource allocation feedback frame 804, the expected duration required for the downlink transmission, the average data rate of the uplink transmission , The average data rate of the downlink transmission, and the like, to the second access point AP2.

In addition, the master access point (M-AP) can assign a bandwidth with a relatively low transmission failure rate to the second access point (AP2) during the interval according to the next resource allocation frame in consideration of the transmission failure rate depending on the bandwidth. For example, if the transmission failure rate below the 40 MHz bandwidth is lower than the 80 MHz bandwidth during the interval according to the previous resource allocation frame, the master access point (M-AP) allocates a 40 MHz bandwidth or less for the interval according to the next resource allocation frame to the second access To the point AP2.

Beacon frame-based coordination

The master access point (M-AP) includes a first resource allocation element for channel coordination with respect to an operation channel and a transmission interval of a first access point (AP), an operation channel of a second access point (AP) And a beacon frame 800 including a second resource allocation element for coordination. Each of the resource allocation elements may be the same as the resource allocation element described above with reference to FIG. Here, when the resource allocation element indicates a plurality of transmission intervals, a plurality of allocated resource fields may exist in one resource allocation element.

The first resource allocation element may comprise two allocated resource fields. The first allocated resource field may include a start time field indicating the duration from the transmission time point of the beacon frame 800 to the start time point of the beacon frame 800, a duration field indicating the duration of T1, and a bandwidth field indicating CH0 to CH3. The second allocated resource field may include a start time field indicating the duration from the transmission time point of the beacon frame 800 to the start time point of T2, a duration field indicating the duration of T2, and a bandwidth field indicating CH0 to CH1. In addition, the first resource allocation element may further include a basic service set identifier (BSSID) of the first access point AP1.

A second resource allocation element may include two allocated resource fields. The first allocated resource field may include a start time field indicating the duration from the transmission time point of the beacon frame 800 to the start time point of T2, a duration field indicating the duration of T2, and a bandwidth field indicating CH3 to CH4. The second allocated resource field may include a start time field indicating the duration from the transmission time point of the beacon frame 800 to the start time point of T3, a duration field indicating the duration of T3, and a bandwidth field indicating CH1 to CH4. In addition, the second resource allocation element may further include a BSSID of the second access point AP2.

On the other hand, the master access point (M-AP) can set a RAW (restricted access window) for each of the resource allocation feedback frames 802 and 804 to ensure transmission of the resource allocation feedback frames 802 and 804 , Beacon frame 800 including the set RAW information can be generated. Alternatively, the master access point (M-AP) can guarantee the transmission of resource allocation feedback frames 802, 804 using the duration field of the beacon frame 800. That is, the duration field of the beacon frame 800 is transmitted from the transmission time point of the beacon frame 800 to the transmission completion time point 802 of the resource allocation feedback frames 802 and 804 in order to guarantee transmission of the resource allocation feedback frames 802 and 804 Can represent the duration up to < RTI ID = 0.0 >

The master access point (M-AP) may transmit the beacon frame 800 in a broadcast manner. At this time, the master access point (M-AP) can transmit the beacon frame (800) in a non-HT duplicate form through CH0 to CH4, which are all operating channels of the master access point (M-AP).

The first access point AP1 may receive the beacon frame 800 from the master access point M-AP and may receive CH0 to CH3 during T1 based on the first resource allocation element included in the beacon frame 800 It is possible to use and check that CH0 ~ CH1 can be used during T2. Thereafter, the first access point (AP1) may generate a resource allocation feedback frame (802). The resource allocation feedback frame 802 may be used to notify the master access point (M-AP) of the resource information required during the interval according to the next resource allocation frame. The resource allocation feedback frame 802 may be the same as the resource allocation feedback frame described above with reference to FIG.

The first access point AP1 may transmit the generated resource allocation feedback frame 802 to the master access point (M-AP). Alternatively, the first access point AP1 may transmit the resource allocation feedback frame 802 generated when an arbitrary poll frame is received from the master access point (M-AP) to the master access point (M-AP). At this time, in order to protect the transmission of the resource allocation feedback frame 802, the first access point AP1 transmits a resource allocation feedback frame 802 to the master access point 802 through the entire operation channels CH0 to CH3, (M-AP).

The master access point (M-AP) may receive the resource allocation feedback frame 802 from the first access point AP1 and may receive the resource allocation information in the next beacon frame based on the information contained in the received resource allocation feedback frame 802 And perform coordination on the corresponding interval.

On the other hand, the second access point AP2 may receive the beacon frame 800 from the master access point (M-AP) and may receive the beacon frame 800 during T2 based on the second resource allocation element included in the beacon frame 800 You can see that CH3 ~ CH4 are available and CH1 ~ CH4 are available during T3. Thereafter, the second access point AP2 may generate a resource allocation feedback frame 804. The resource allocation feedback frame 804 may be used to inform the master access point (M-AP) of the resource information required during the interval according to the next resource allocation frame. The resource allocation feedback frame 804 may be the same as the resource allocation feedback frame described above with reference to FIG.

The second access point AP2 may transmit the generated resource allocation feedback frame 804 to the master access point (M-AP). Alternatively, the second access point AP2 may transmit the generated resource allocation feedback frame 804 to the master access point (M-AP) when receiving an arbitrary poll frame from the master access point (M-AP). At this time, to protect the transmission of the resource allocation feedback frame 804, the second access point AP2 transmits a resource allocation feedback frame 804 in the form of a non-HT Duplicate to the master access point 804 through CH1- (M-AP).

The master access point (M-AP) may receive the resource allocation feedback frame (804) from the second access point (AP2) and may receive the resource allocation information in the next beacon frame based on the information contained in the received resource allocation feedback frame And perform coordination on the corresponding interval.

On the other hand, when the master access point (M-AP) and the access points (AP1, AP2) are hidden access points, the resource allocation element and the resource allocation feedback frame can be transmitted and received via the wire.

Next, the frame transmission / reception procedure of each of the access points AP1 and AP2 will be described. The frame transmission / reception procedure will be described collectively because it is the same in the coordination scheme based on the resource allocation frame or the coordination scheme based on the beacon frame.

The first access point AP1 can transmit and receive frames with terminals belonging to the BSS1 using CH0 to CH4 at T1. That is, the first access point AP1 may transmit a beacon frame 805 to inform that data for at least one terminal belonging to the BSS1 is buffered. The beacon frame 805 also includes DL RAW information for transmission of the downlink data frames 808, 809, 811 and 812 and UL RAW information for transmission of the uplink data frames 810 and 813 . That is, the transmission and reception of the downlink data frames 808, 809, 811 and 812 can be performed in the DL RAW, and the transmission and reception of the uplink data frames 810 and 813 can be performed in the UL RAW.

 The first access point AP1 may receive power save (PS) -Poll frames 806 and 807 from the terminals belonging to the BSS1, And then transmit the downlink data frames 808 and 809. [ Also, the first access point AP1 may receive the uplink data frame 810 from the terminal belonging to the BSS1. Thereafter, the first access point AP1 can transmit and receive frames with terminals belonging to the BSS1 using CH0 to CH1 at T2. That is, the first access point AP1 can transmit the downlink data frames 811 and 812 to the terminals belonging to the BSS1 and the uplink frame 813 from the terminals belonging to the BSS1.

On the other hand, the second access point AP2 can transmit and receive frames with terminals belonging to the BSS2 using CH3 to CH4 in T2. That is, the second access point AP2 can inform that the data for at least one terminal belonging to the BSS2 is buffered by transmitting the beacon frame 814. [ The beacon frame 814 may include DL RAW information for transmission of the downlink data frames 817, 818, 819 and 820 and UL RAW information for transmission of the uplink data frame 821. [ That is, the transmission and reception of the downlink data frames 817, 818, 819 and 820 can be performed in the DL RAW, and the transmission and reception of the uplink data frame 821 can be performed in the UL RAW.

The second access point AP2 may receive the PS-Poll frames 815 and 816 from the terminals belonging to the BSS2 and after confirming that the terminals are awake through the PS-Poll frames 815 and 816, Link data frames 817 and 818 may be transmitted. That is, the second access point AP2 can perform simultaneous transmission with the first access point AP1 over the narrow band for T2.

Thereafter, the second access point AP2 can transmit and receive frames with terminals belonging to the BSS2 using CH1 to CH4 at T3. That is, the second access point AP2 can transmit the downlink data frames 819 and 820 to the terminals belonging to the BSS2 and can receive the uplink frame 821 from the terminals belonging to the BSS2.

Embodiments of the present invention may be implemented in the form of program instructions that can be executed through various computer means and recorded on a computer readable medium. The computer readable medium may include program instructions, data files, data structures, and the like, alone or in combination. Program instructions to be recorded on a computer-readable medium may be those specially designed and constructed for embodiments of the present invention or may be available to those skilled in the art of computer software.

The computer-readable medium may refer to a hardware device that is specifically configured to store and execute program instructions, such as a ROM, a RAM, a flash memory, and the like. A hardware device may be configured to operate with at least one software module to perform operations in accordance with embodiments of the present invention, and vice versa. A program instruction may refer to a high-level language code that may be executed on a computer based on, for example, an interpreter, as well as machine code as produced by a compiler.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined in the appended claims. It will be possible.

Claims (20)

A channel setting method performed at a first access point,
The method comprising: receiving a first frame from a second access point, the first frame including scheduling information for a first interval;
Generating a second frame including resource related information required for transmission and reception through a second interval following the first interval; And
And transmitting the second frame to the second access point. The method according to claim 1,
Wherein the first frame is a beacon frame. The method according to claim 1,
Wherein the first frame includes duration information indicating a transmission start time of the first frame to a transmission end time of the second frame. The method according to claim 1,
Wherein the first frame includes limited connection window information indicating a transmission period of the second frame. The method according to claim 1,
Wherein the first frame is received at the beginning of the first interval. The method according to claim 1,
The scheduling information includes:
And at least one of an operation channel and a transmission interval of the first access point during the first interval. The method according to claim 1,
The resource-
A transmission rate of the first interval prior to the first interval and a transmission rate of the second interval before the transmission of the second interval, the expected duration information required for frame transmission / reception over the second interval, the data rate in the first interval previous interval, How to set it up. The method according to claim 1,
Wherein transmitting the second frame to the second access point comprises:
And transmit the second frame to the second access point if a poll frame is received from the second access point. The method according to claim 1,
The channel setting method includes:
And transmitting and receiving a frame with at least one terminal connected to the first access point within an operation channel and a transmission interval indicated by the scheduling information. A channel management method performed at a second access point,
Generating a first frame including scheduling information for a first interval;
Transmitting the first frame to a first access point; And
Receiving a second frame from the first access point, the second frame including resource related information required for transmission and reception through a second interval following the first interval. The method of claim 10,
Wherein the first frame is a resource allocation frame. The method of claim 10,
Wherein the first frame comprises:
The beacon frame of the second access point is transmitted to the first access point after being transmitted. The method of claim 10,
The scheduling information includes:
And at least one of an operation channel and a transmission interval of the first access point during the first interval. The method of claim 10,
The resource-
A transmission rate of the first interval prior to the first interval and a transmission rate of the second interval before the transmission of the second interval, the expected duration information required for frame transmission / reception over the second interval, the data rate in the first interval previous interval, How to manage. The method of claim 10,
The channel management method includes:
And generating scheduling information for the second interval based on the resource-related information. As a first access point,
A processor; And
Wherein at least one instruction executed through the processor includes a memory,
Wherein the at least one instruction comprises:
The method comprising: receiving a first frame from a second access point, the first frame including scheduling information for a first interval;
Generating a second frame including resource related information required for transmission and reception through a second interval following the first interval; And
And transmitting the second frame to the second access point. 18. The method of claim 16,
The scheduling information includes:
Wherein the first access point comprises at least one of an operating channel and a transmission interval of the first access point during the first interval. 18. The method of claim 16,
The resource-
A transmission rate of the first interval, a transmission rate of the second interval, a transmission rate of the second interval, a transmission rate of the second interval, a transmission rate of the second interval, 1 Access point. 18. The method of claim 16,
Wherein transmitting the second frame to the second access point comprises:
And transmit the second frame to the second access point when a resource allocation frame is received from the second access point. 18. The method of claim 16,
Wherein the at least one instruction comprises:
And transmitting and receiving a frame with at least one terminal connected to the first access point within an operating channel and a transmission interval indicated by the scheduling information.

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