KR20210157301A - Apparatus and method for coordinated spatial reuse - Google Patents

Abstract

A wireless communication method performed by a first device includes the steps of: acquiring a transmit opportunity (TXOP) to transmit or receive a first physical layer protocol data unit (PPDU); identifying a second device to share the TXOP; permitting at least one of transmission and reception of a second PPDU, to the second device in the shared TXOP; and transmitting or receiving the first PPDU to or from a third device in the shared TXOP.

Description

APPARATUS AND METHOD FOR COORDINATED SPATIAL REUSE

The technical idea of the present disclosure relates to wireless communication, and more particularly, to an apparatus and method for cooperative space reuse in wireless communication.

As an example of wireless communication, a wireless local area network (WLAN) is a technology for connecting two or more devices to each other using a wireless signal transmission method, and the WLAN technology may be based on an Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard. The 802.11 standard has evolved into 802.11b, 802.11a, 802.11g, 802.11n, 802.11ac, and 802.11ax, and based on Orthogonal frequency-division multiplexing (OFDM) technology, provides transmission rates up to 1 Gbyte/s. can support

In 802.11ac, data may be simultaneously transmitted to multiple users through a multi-user multi-input multi-output (MU-MIMO) technique. In 802.11ax, referred to as High Efficiency (HE), not only MU-MIMO but also Orthogonal Frequency-Division Multiple Access (OFDMA) technology is applied to divide and provide available subcarriers to users, thereby providing multiple access. is implementing Through this, the WLAN system to which 802.11ax is applied can effectively support communication in dense areas and outdoors.

In 802.11be, which is called Extremely High Throughput (EHT), 6GHz unlicensed frequency band support, bandwidth utilization of up to 320MHz per channel, Hybrid Automatic Repeat and reQuest (HARQ) introduction, up to 16X16 MIMO support, etc. are to be implemented. Through this, the next-generation WLAN system is expected to effectively support low latency and high-speed transmission like NR (New Radio), a 5G technology.

The technical idea of the present disclosure provides an apparatus and method for efficiently performing spatial reuse in wireless communication.

According to an aspect of the technical concept of the present disclosure, a wireless communication method performed by a first device includes: acquiring a transmit opportunity (TXOP) to transmit or receive a first physical layer protocol data unit (PPDU); TXOP identifying a second device for sharing transmitting to or receiving from at least one third device.

According to an aspect of the inventive concept, a first device for wireless communication includes a transceiver, and a second device for transmitting or receiving a first PPDU through the transceiver to obtain a TXOP, and to share the TXOP and permit at least one of transmission and reception of the second PPDU to the second device through the transceiver in the shared TXOP, and transmit the first PPDU to at least one third device through the transceiver in the shared TXOP or at least one processing circuitry configured to receive from a third device.

According to an aspect of the technical concept of the present disclosure, a wireless communication method performed by a first device includes: acquiring a TXOP to transmit or receive a first PPDU; identifying a second device for sharing the TXOP; , providing a second device with a tolerable interference limit of transmission or reception of the first PPDU in the shared TXOP, and transmitting the first PPDU to at least one third device in the shared TXOP or at least one may include receiving from a third device of

According to an aspect of the inventive concept, a wireless communication method performed by a first device and a third device associated with a second device in a TXOP shared by the second device includes: Receiving the frame, determining a path loss between the first device and the third device based on the frame, transmitting information about the path loss to the second device, and in the shared TXOP, sending the PPDU to the second device receiving from or transmitting to a second device.

According to the apparatus and method according to an exemplary embodiment of the present disclosure, space reuse can be efficiently performed in wireless communication, and thus spectral efficiency and throughput can be increased.

Effects that can be obtained in the exemplary embodiments of the present disclosure are not limited to the above-mentioned effects, and other effects not mentioned are common knowledge in the art to which exemplary embodiments of the present disclosure pertain from the following description. It can be clearly derived and understood by those who have That is, unintended effects of carrying out the exemplary embodiments of the present disclosure may also be derived by those of ordinary skill in the art from the exemplary embodiments of the present disclosure.

1 is a diagram illustrating a wireless communication system according to an exemplary embodiment of the present disclosure.
2 is a block diagram illustrating a wireless communication system according to an exemplary embodiment of the present disclosure.
3A to 3D are diagrams illustrating scenarios of collaborative space reuse according to exemplary embodiments of the present disclosure.
4 is a message diagram illustrating a method for collaborative space reuse according to an exemplary embodiment of the present disclosure.
5 is a diagram illustrating an example of information provided by a shared access point to a shared access point according to an exemplary embodiment of the present disclosure.
6 is a message diagram illustrating a method for collaborative space reuse according to an exemplary embodiment of the present disclosure.
7 is a diagram illustrating a wireless communication system according to an exemplary embodiment of the present disclosure.
8A and 8B are diagrams illustrating examples of a wireless communication system according to exemplary embodiments of the present disclosure.
9 is a message diagram illustrating a method for collaborative space reuse according to an exemplary embodiment of the present disclosure.
10 is a message diagram illustrating a method for collaborative space reuse according to an exemplary embodiment of the present disclosure.
11 is a message diagram illustrating a method for collaborative space reuse according to an exemplary embodiment of the present disclosure.
12 is a diagram illustrating a frame according to an exemplary embodiment of the present disclosure.
13 is a timing diagram illustrating transmission based on cooperative space reuse according to an exemplary embodiment of the present disclosure;
14 is a timing diagram illustrating transmission based on cooperative space reuse according to an exemplary embodiment of the present disclosure.
15A and 15B are timing diagrams illustrating transmission based on cooperative space reuse according to example embodiments of the present disclosure.
16 is a diagram illustrating a wireless communication system according to an exemplary embodiment of the present disclosure.
17 is a diagram illustrating examples of an apparatus for wireless communication according to an exemplary embodiment of the present disclosure.

1 is a diagram illustrating a wireless communication system 10 according to an exemplary embodiment of the present disclosure. In some embodiments, the wireless communication system may be a wireless local area network (WLAN) system.

Hereinafter, in describing the embodiments of the present disclosure in detail, OFDM or OFDMA-based wireless communication systems, in particular, IEEE 802.11 standards will be mainly targeted, but the main subject matter of the present disclosure has a similar technical background and channel type. Other communication systems (eg, long term evolution (LTE), LTE-Advanced (LTE-A), New Radio (NR), Wireless Broadband (WiBro), cellular such as Global System for Mobile Communication (GSM) ) communication system or short-distance communication system such as Bluetooth (Bluetooth), NFC (Near Field Communication)) can be applied with slight modifications within the range that does not significantly depart from the scope of the present disclosure, which is It will be possible at the discretion of a person with technical knowledge.

In addition, various functions described below may be implemented or supported by one or more computer programs, each of which consists of computer readable program code and is implemented in a computer readable medium. The terms "application" and "program" refer to one or more computer programs, software components, sets of instructions, procedures, functions, objects, classes, instances, related data, or portions thereof suitable for implementation of suitable computer readable program code. The term "computer readable program code" includes computer code of any type, including source code, object code, and executable code. The term "computer-readable medium" means a computer, such as read only memory (ROM), random access memory (RAM), hard disk drive, compact disk (CD), digital video disk (DVD), or any other type of memory. It includes all types of media that can be accessed by “Non-transitory” computer-readable media excludes wired, wireless, optical, or other communication links that transmit transitory electrical or other signals. Non-transitory computer-readable media includes media in which data can be permanently stored, and media in which data can be stored and later overwritten, such as a rewritable optical disk or a removable memory device.

The wireless communication system 10 may extend a service area by an access point (AP). A station (STA) may communicate with the access point in a basic service set (BSS) provided by the access point, and may access a network such as the Internet or an IP (internet protocol) network through the access point. For example, as shown in FIG. 1 , the first access point AP1 may provide the first BSS BSS1, and the first station STA1, the third station STA3, and the fourth station ( STA4) and the fifth station STA5 may communicate with the first access point AP1. In addition, the second access point AP2 may provide the second BSS BSS2, and the first station STA1, the second station STA2, the third station STA3, and the sixth station STA6 are It can communicate with the second access point AP2. As shown in FIG. 1 , a first station STA1 and a third station STA3 may access both the first access point AP1 and the second access point AP2 . In FIG. 1 , dotted lines indicate approximate extents of each of the first BSS ( BSS1 ) and the second BSS ( BSS2 ), and may have a shape different from the circle shown in FIG. 1 .

The access point and station may communicate with each other using wireless fidelity (WiFi) or any other WLAN communication technology. An access point may be referred to as a router, a gateway, or the like, and the station is a mobile station, a subscriber station, a terminal, a mobile terminal, a wireless terminal, user equipment, and a user. and the like. The station may be a portable device, such as a mobile phone, a laptop computer, a wearable device, or the like, or a stationary device, such as a desktop computer, a smart TV, or the like. Examples of an access point and station will be described below with reference to FIG. 17 .

802.11-based MAC (medium access control) protocol may consider that two or more signal transmissions are performed simultaneously as collision, and accordingly, access points and stations may use a channel through contention. For example, the access point and the station may communicate with each other based on carrier sense multiple access (CSMA) and/or collision avoidance (CA), so that the first access point AP1 is the first station STA1 . While performing transmission for , the second access point AP2 may defer transmission to the third station STA3 . Collision may occur frequently in an overlapping basic service set (OBSS) environment in which a plurality of access points and a plurality of stations exist, and thus the performance of the wireless communication system 10, such as throughput, may be limited. .

Spatial reuse (SR) may enable conflicting transmissions to occur simultaneously. For example, while the first access point AP1 performs a first transmission to the first station STA1 , the second access point AP2 delays transmission to the second station STA2 , instead of, The second transmission to the second station STA2 may be performed with a level of transmission power that does not interfere with reception of the first station STA1 . Accordingly, the first transmission to the first station STA1 and the second transmission to the second station STA2 may be performed in parallel, and the transmission amount may increase in the wireless communication system 10 . In this specification, a transmission associated with an access point that has obtained a TXOP may be referred to as a first transmission, and a transmission associated with an access point that has received a shared TXOP may be referred to as a second transmission.

In 802.11ax, the access point or station may identify a first transmission based on a preamble, and if the first transmission is identified, at least partially overlap the first transmission with a transmit power determined based on the received power of the preamble. The second transmission may be performed. However, the second transmission may not be considered in the first transmission, and thus the efficiency of space reuse may be limited. As will be described below with reference to the drawings, in spatial reuse, not only the second transmission considers the first transmission, but also the first transmission may consider the second transmission, and thus more efficient spatial reuse may be achieved.

In this specification, spatial reuse in which a first transmission considers a second transmission may be referred to as coordinated spatial reuse (C-SR). In addition, the access point related to the first transmission (ie, obtained a transmit opportunity (TXOP)) may be referred to as a sharing access point, and a BSS provided by the sharing access point may be referred to as a shared BSS. can The access point associated with the second transmission may be referred to as a shared access point, and a BSS provided by the shared access point may be referred to as a shared BSS. Unless otherwise specified, it is assumed that the first access point AP1 is a shared access point, and the second access point AP2 is assumed as a shared access point. The first access point AP1 and the second access point AP2 may be referred to as a first apparatus and a second apparatus, respectively, and each of the stations may be referred to as a third apparatus or a fourth apparatus. A physical layer protocol data unit (PPDU) transmitted between the first access point AP1 and at least one station included in the first BBS provided by the first access point AP1 is referred to as a first PPDU. A PPDU transmitted between the second access point AP2 and at least one station included in the second BBS BBS2 provided by the second access point AP2 may be referred to as a second PPDU.

2 is a block diagram illustrating a wireless communication system 20 according to an exemplary embodiment of the present disclosure. Specifically, the block diagram of FIG. 2 shows a first wireless communication device 21 and a second wireless communication device 22 that communicate with each other in the wireless communication system 20 . Each of the first wireless communication device 21 and the second wireless communication device 22 of FIG. 2 may be any device that communicates in the wireless communication system 20 and may be referred to as a device for wireless communication. In some embodiments, each of the first wireless communication device 21 and the second wireless communication device 22 may be an access point or station of a WLAN system.

Referring to FIG. 2 , the first wireless communication device 21 may include an antenna 21_2 , a transceiver 21_4 , and a processing circuit 21_6 . In some embodiments, the antenna 21_2 , the transceiver 21_4 , and the processing circuit 21_6 may be included in one package or may be included in different packages, respectively. The second wireless communication device 22 may also include an antenna 22_2 , a transceiver 22_4 , and a processing circuit 22_6 . Hereinafter, redundant descriptions of the first wireless communication device 21 and the second wireless communication device 22 will be omitted.

The antenna 21_2 may receive a signal from the second wireless communication device 22 and provide it to the transceiver 21_4 , and may transmit the signal provided from the transceiver 21_4 to the second wireless communication device 22 . In some embodiments, the antenna 21_2 may include a plurality of antennas for multiple input multiple output (MIMO). Also, in some embodiments, the antenna 21_2 may include a phased array for beamforming.

The transceiver 21_4 may process a signal received from the second wireless communication device 22 through the antenna 21_2 , and may provide the processed signal to the processing circuit 21_6 . In addition, the transceiver 21_4 may process the signal provided from the processing circuit 21_6 and output the processed signal through the antenna 21_2 . In some embodiments, the transceiver 21_4 may include an analog circuit such as a low noise amplifier, a mixer, a filter, a power amplifier, an oscillator, and the like. In some embodiments, the transceiver 21_4 may process a signal received from the antenna 21_2 and/or a signal received from the processing circuit 21_6 based on the control of the processing circuit 21_6 .

The processing circuit 21_6 may extract information transmitted by the second wireless communication device 22 by processing the signal received from the transceiver 21_4 . For example, the processing circuit 21_6 may extract information by demodulating and/or decoding a signal received from the transceiver 21_4 . In addition, a signal including information to be transmitted to the second wireless communication device 22 may be generated and provided to the transceiver 21_4 . For example, the processing circuit 21_6 may provide a signal generated by encoding and/or modulating data to be transmitted to the second wireless communication device 22 to the transceiver 21_4 . In some embodiments, the processing circuit 21_6 may include a programmable component, such as a central processing unit (CPU), a digital signal processor (DSP), etc., such as a field programmable gate array (FPGA), or the like. It may include a reconfigurable component, and may include a component that provides a fixed function, such as an intellectual property (IP) core. In some embodiments, the processing circuit 21_6 may include or access memory that stores data and/or a series of instructions. In this specification, the transceiver 21_4 and/or the processing circuit 21_6 performing the operations may simply be referred to as the first wireless communication device 21 performing the corresponding operations. Accordingly, operations performed by the access point may be performed by the transceiver and/or processing circuitry included in the access point, and operations performed by the station may be performed by the transceiver and/or processing circuitry included in the station. can

3A to 3D are diagrams illustrating scenarios of collaborative space reuse according to exemplary embodiments of the present disclosure. Specifically, FIGS. 3A to 3D illustrate a radio including a first access point AP1 , a second access point AP2 , a first station STA1 , a second station STA2 , and a third station STA3 . Communication systems 30a, 30b, 30c, and 30d are shown respectively. Hereinafter, transmission of the PPDU including data by the access point to the station may be referred to as downlink (DL) transmission, and the transmission of the PPDU including data by the station to the access point in uplink (uplink). UL) transmission. Among the descriptions of FIGS. 3A to 3D, the content overlapping with the description of FIG. 1 will be omitted.

Referring to FIG. 3A , a first downlink transmission DL1 of a first BSS (BSS1) and a second downlink transmission DL2 of a second BSS (BSS2) may occur. For example, the first access point AP1 may acquire the TXOP to transmit the first PPDU to the first station STA1 . The first access point AP1 may transmit a first PPDU to the first station STA1 in the shared TXOP, and the second access point AP1 may transmit the second PPDU in the shared TXOP to the second station STA2. can be sent to 3A , the second downlink transmission DL2 may act as an interference in processing the first downlink transmission DL1 by the first station STA1 . As the transmission power of the second downlink transmission DL2 is higher, a signal-to-interference ratio (SIR) in the first station STA1 may decrease, and accordingly, the second access point AP2 ) may be required to perform the second downlink transmission DL2 in consideration of an appropriate signal-to-interference ratio of the first station STA1. In this specification, the example of FIG. 3A may be referred to as a DL/DL scenario or DL/DL case of cooperative space reuse.

In some embodiments, differently as shown in FIG. 3A , the first access point AP1 may provide downlink transmission to a multi-user (MU), ie, a plurality of stations. Further, in some embodiments, the second access point AP2 may also provide downlink transmission to a plurality of stations. In the present specification, the DL/DL scenario or DL/DL case of cooperative spatial reuse may encompass the above-described multi-user downlink transmission as well as the single user (SU) downlink transmissions shown in FIG. 3A. point is noted.

Referring to FIG. 3B , a first uplink transmission UL1 of a first BSS (BSS1) and a second downlink transmission DL2 of a second BSS (BSS2) may occur. For example, the first access point AP1 may acquire the TXOP to receive the first PPDU from the first station STA1 . The first station STA1 may transmit a first PPDU to the first access point AP1 in the shared TXOP, and the second access point AP2 transmits the second PPDU in the shared TXOP to the second station STA2. can be sent to As shown by a dotted arrow in FIG. 3B , the second downlink transmission DL2 may act as an interference for the first access point AP1 to process the first uplink transmission UL1 . As the transmission power of the second downlink transmission DL2 is higher, the signal-to-interference ratio in the first access point AP1 may decrease, and accordingly, the second access point AP2 is the first access point AP1. It may be required to perform the second downlink transmission (DL2) in consideration of an appropriate signal-to-interference ratio. In this specification, the example of FIG. 3B may be referred to as a UL/DL scenario or UL/DL case of cooperative space reuse.

In some embodiments, different as shown in FIG. 3B , multiple users, ie, multiple stations, may provide uplink transmissions to the first access point AP1 . Also, in some embodiments, the second access point AP2 may provide downlink transmission to a plurality of stations. In the present specification, the UL/DL scenario or UL/DL case of cooperative spatial reuse includes not only single-user uplink transmission and single-user downlink transmission shown in FIG. 3B, but also multi-user uplink transmission and/or multi-user downlink transmission. It is noted that transmission may be encompassed.

Referring to FIG. 3C , a first downlink transmission DL1 of a first BSS (BSS1) and second uplink transmissions UL21 and UL22 of a second BSS (BSS2) may occur. For example, the first access point AP1 may acquire a TXOP to transmit the first PPDU. The first access point AP1 may transmit a first PPDU to the first station STA1 in the shared TXOP, and the second station STA2 and the third station STA3 transmit the second PPDUs in the shared TXOP. It can transmit to the second access point (AP2). As shown by dotted arrows in FIG. 3C , the second uplink transmissions UL21 and UL22 may act as interference in processing the first downlink transmission DL1 . As the transmission powers of the second uplink transmissions UL21 and UL22 are higher, the signal-to-interference ratio in the first station STA1 may decrease, and accordingly, the second station STA2 and the third station STA3 may It may be required to perform the second uplink transmissions UL21 and UL22 in consideration of an appropriate signal-to-interference ratio of the first station STA1. In this specification, the example of FIG. 3C may be referred to as a DL/UL scenario or DL/UL case of cooperative space reuse.

In some embodiments, differently as shown in FIG. 3C , the first access point AP1 may provide downlink transmission to a multi-user (MU), ie, a plurality of stations. Also, in some embodiments, a single user, ie, one station, may provide uplink transmission to the second access point AP2. In the present specification, the DL/UL scenario or DL/UL case of cooperative spatial reuse includes not only single-user downlink transmission and multi-user uplink transmission shown in FIG. 3C, but also multi-user downlink transmission and/or single user uplink transmission. It is noted that transmission may be encompassed.

Referring to FIG. 3D , a first uplink transmission UL1 of a first BSS (BSS1) and second uplink transmissions UL21 and UL22 of a second BSS (BSS2) may occur. For example, the first access point AP1 may acquire a TXOP to receive the first PPDU. The first station STA1 may transmit a first PPDU to the first access point AP1 in the shared TXOP, and the second station STA2 and the third station STA3 transmit the second PPDUs in the shared TXOP. It can transmit to the second access point (AP2). As shown by dotted arrows in FIG. 3D , the second uplink transmissions UL21 and UL22 may act as interference in processing the first uplink transmission UL1 . As the transmission powers of the second uplink transmissions UL21 and UL22 are higher, the signal-to-interference ratio in the first access point AP1 may decrease, and accordingly, the second station STA2 and the third station STA3 In consideration of an appropriate signal-to-interference ratio of the first access point AP1, it may be required to perform the second uplink transmissions UL21 and UL22. In this specification, the example of FIG. 3D may be referred to as a UL/UL scenario or UL/UL case of cooperative space reuse. Examples of a method for cooperative space reuse respectively corresponding to the scenarios described above with reference to FIGS. 3A to 3D will be described below with reference to the drawings.

In some embodiments, different as shown in FIG. 3D , multiple users, ie, multiple stations, may provide uplink transmissions to the first access point AP1 . Also, in some embodiments, a single user, ie, one station, may provide uplink transmission to the second access point AP2. In the present specification, the UL/UL scenario or UL/UL case of cooperative spatial reuse includes not only single-user uplink transmission and multi-user uplink transmission shown in FIG. 3D, but also multi-user uplink transmission and/or single user uplink transmission. It is noted that transmission may be encompassed.

4 is a message diagram illustrating a method for collaborative space reuse according to an exemplary embodiment of the present disclosure. As shown in FIG. 4 , the method for cooperative space reuse may include a plurality of operations S41 to S45 . As described above with reference to FIG. 1 , the first access point AP1 of FIG. 4 may be a shared access point, and the second access point AP2 may be a shared access point. In FIG. 4 , a first station STA1 may be related to a first access point AP1 in a first BSS provided by a first access point AP1, and a second station STA2 may be associated with a second access point ( AP2) may be related to the second access point (AP2) in the second BSS provided.

Referring to FIG. 4 , in step S41 , the first access point AP1 may acquire a TXOP. For example, the first access point AP1 may acquire the TXOP in order to transmit the first PPDU to the first station STA1 or to receive it from the first station STA1 . As described above with reference to FIG. 1 , the first access point AP1 may acquire the TXOP through contention with at least one station or another access point. For space reuse, the TXOP obtained by the first access point AP1 may be shared with the second access point AP2.

In step S42 , the first access point AP1 may share the TXOP with the second access point AP2 . For example, the first access point AP1 may share the TXOP with the second access point AP2 in the shared TXOP. At least one of transmission and reception of the second PPDU may be permitted. The first access point AP1 may permit uplink transmission and/or downlink transmission in the second BSS so as not to interfere with the transmission or reception of the first PPDU in the first BSS. In some embodiments, the first access point AP1 transmits a signal (eg, AF or PPDU0 in FIG. 13 ) including information indicating permission of uplink transmission and/or downlink transmission to the second access point AP2 can be sent to An example of information indicating permission of uplink transmission and/or downlink transmission will be described later with reference to FIG. 5 .

As will be described later with reference to FIGS. 8A and 8B , estimating interference by the second transmission by the first access point AP1 is higher in the uplink in the second BSS than in the case in which downlink transmission occurs in the second BSS. It can be more difficult when transmission occurs. Accordingly, the first access point AP1 may permit at least one of uplink transmission and downlink transmission to the second access point AP2 so as not to interfere with the transmission or reception of the first PPDU. In some embodiments, when a path loss between the first access point AP1 and the first station STA1 is higher than a predefined threshold, the first access point AP1 Only downlink transmission may be permitted to AP2). In some embodiments, cooperative spatial reuse may define only downlink transmission in a shared BSS (ie, second BSS), and thus step S42 and step S43 described below may be omitted, and the second access point ( AP2) may only perform downlink transmission, that is, transmission of the second PPDU in the shared TXOP.

In step S43, the second access point AP2 may identify at least one of the allowed uplink transmission and the downlink transmission. For example, the second access point AP2 may extract information permitting uplink transmission and/or downlink transmission from a signal received from the first access point AP1 in step S42 . In some embodiments, when uplink transmission is permitted, the second access point AP2 may transmit a trigger frame to the second station STA2 to receive the second PPDU (PPDU2).

A first PPDU (PPDU1) may be transmitted between the first access point (AP1) and the first station (STA1) in step S44, and between the second access point (AP2) and the second station (STA2) in step S45 A second PPDU (PPDU2) may be transmitted. For example, in step S44, the first access point AP1 may transmit a first PPDU (PPDU1) to the first station STA1 in the shared TXOP, and the first station STA1 may transmit the first PPDU (PPDU1) to the first station STA1 in the shared TXOP. One PPDU (PPDU1) may be transmitted to the first access point AP1. In addition, when uplink transmission is identified in step S43, the second station STA2 may transmit a second PPDU (PPDU2) to the second access point AP2, and when downlink transmission is identified in step S43, the second station STA2 The second access point AP2 may transmit a second PPDU (PPDU2) to the second station STA2.

5 is a diagram illustrating an example of information provided by a shared access point to a shared access point according to an exemplary embodiment of the present disclosure. Specifically, FIG. 5 is a table including values provided by the first access point AP1 to permit at least one of uplink transmission and downlink transmission to the second access point AP2 in step S42 of FIG. 4 . indicates. Hereinafter, FIG. 5 will be described with reference to FIG. 4 .

In some embodiments, grant of at least one of uplink transmission and downlink transmission may be expressed as a value of 2-bit. For example, as shown in FIG. 5 , a most significant bit (MSB) of 2-bits may indicate whether downlink transmission is permitted, and a least significant bit (LSB) of 2-bits may indicate permission of uplink transmission. can indicate whether Accordingly, "01" may correspond to permission of uplink transmission, "10" may correspond to permission of downlink transmission, and "11" may correspond to permission of both uplink transmission and downlink transmission. In some embodiments, as described below with reference to FIG. 13 , the 2-bit of FIG. 5 is an announcement frame transmitted from the first access point AP1 to the second access point AP2 (eg, FIG. 13 ). It may correspond to a field included in AF). In some embodiments, 2-bits with different values from those shown in FIG. 5 may be used to represent the three combinations described above.

6 is a message diagram illustrating a method for collaborative space reuse according to an exemplary embodiment of the present disclosure. Specifically, the message diagram of FIG. 6 shows operations performed in each of the DL/DL scenario and the UL/DL scenario of cooperative space reuse, as described above with reference to FIGS. 3A and 3B . As shown in FIG. 6 , the method for collaborative space reuse may include a plurality of steps S60 to S69 . In FIG. 6 , a first station STA1 may be included in a first BSS provided by a first access point AP1 , and a second station STA2 may be included in a second BSS provided by a second access point AP2 . may be included. In addition, in FIG. 6 , it is assumed that the first access point AP1 has acquired the TXOP before steps S60 and S65 are respectively performed.

Referring to FIG. 6 , in step S60 , the first access point AP1 may determine a transmission power limit (TPL) in the shared TXOP. The transmit power limit may correspond to the maximum transmit power allowed when the second access point AP2 transmits the second PPDU to the second station STA2 in the shared TXOP. For example, the first access point AP1 may obtain a TXOP to transmit a first PPDU to the first station STA1 , and transmit based on at least one path loss associated with the first station STA1 . Power limits can be determined. An example of an operation of determining a transmit power limit in a DL/DL scenario and a UL/DL scenario of cooperative space reuse will be described below with reference to FIG. 7 .

In step S61 , the first access point AP1 may provide a transmit power limit to the second access point AP2 . For example, the first access point AP1 may transmit a signal including the transmission power limit determined in step S60 to the second access point AP2 . In some embodiments, as described below with reference to FIG. 13 , the transmit power limit may be included in the announcement frame.

In step S62, the second access point AP2 may identify a transmit power limit. For example, the second access point AP2 may extract a transmit power limit from a signal received from the first access point AP1 in step S61 . In some embodiments, the transmit power limit may have the same format as a transmit power field included in a transmit power control (TPC) report, and the second access point AP2 transmits a transmit power corresponding to a value of the transmit power field. limitations can be identified.

In step S63, the first access point AP1 may transmit a first PPDU to the first station STA1 in the shared TXOP, and in step S64, the second access point AP2 transmits a second PPDU in the shared TXOP It can transmit to the second station STA2. The second access point AP2 may transmit the second PPDU with a transmit power equal to or less than the transmit power limit identified in step S62, and accordingly, interference due to transmission of the second PPDU may be reduced or eliminated, and The first station STA1 may successfully receive the first PPDU.

In step S65, the first access point AP1 may determine a transmit power limit in the shared TXOP. For example, the first access point AP1 may acquire a TXOP to receive a first PPDU from the first station STA1, based on at least one path loss associated with the first access point AP1. to determine the transmit power limit. An example of the operation of determining the transmit power limit will be described below with reference to FIG. 7 .

In step S66 , the first access point AP1 may provide a transmit power limit to the second access point AP2 . In step S67, the second access point AP2 may identify a transmit power limit.

In step S68, the first station STA1 may transmit a first PPDU to the first access point AP1 in the shared TXOP, and in step S69, the second access point AP2 transmits a second PPDU in the shared TXOP It can transmit to the second station STA2. The second access point AP2 may transmit the second PPDU with a transmit power equal to or less than the transmit power limit identified in step S62, and accordingly, interference due to transmission of the second PPDU may be reduced or eliminated, and One access point AP1 may successfully receive the first PPDU.

7 is a diagram illustrating a wireless communication system 70 according to an exemplary embodiment of the present disclosure. Specifically, the diagram of FIG. 7 shows examples of path loss considered in cooperative space reuse when downlink transmission occurs in a shared BBS. _{As shown in FIG. 7 , a first path loss PL 1} between the first access point AP1 and the first station STA1 , a second path between the second access point AP2 and the second station STA2 . A loss PL _{2 and a third path loss PL 3} between the first access point AP1 and the second access point AP2 may be considered. In addition, the first access point AP1 may provide a first BSS (BSS1), the second access point AP2 may provide a second BSS (BSS2), and the first station STA1 may provide a first BSS (BSS1). It may be included in 1 BSS (BSS1).

In a DL/DL scenario (eg, in step S60 of FIG. 6 ), a transmit power limit may be determined based on _{the first pathloss PL 1} and the second pathloss PL _{2 .} For example, the first path loss PL ₁ may correspond to a loss of a signal transmitted by the first access point AP1 , and the second path loss PL ₂ may correspond to a signal transmitted by the second access point AP2 . It can cope with signal loss. As the first path loss PL ₁ is low and the second path loss PL ₂ is high, it may be advantageous for the first station STA1 to successfully receive the first PPDU from the first access point AP1 . Accordingly, the first access point AP1 determines a transmit power limit based on the transmit power of the first access point AP1 , the first path loss PL ₁ , and the second path loss PL _{2 .} can For example, in the DL/DL scenario, the transmit power limit TPL _AP2 is the minimum signal required for the transmit power of the first access point AP1 to be P _AP1 and the first station STA1 to successfully receive the first PPDU. When the to-interference ratio is SIR _STA1 , the following [Equation 1] may be satisfied.

In the UL/DL scenario (eg, in step S65 of FIG. 6 ), a transmit power limit may be determined based on _{the first pathloss PL 1} and the third pathloss PL _{3 .} For example, the first path loss PL ₁ may correspond to a loss of a signal transmitted by the first access point AP1 , and the third path loss PL ₃ may correspond to a signal loss transmitted by the second access point AP2 . It can cope with signal loss. As the first path loss PL ₁ is low and the third path loss PL ₃ is high, it may be advantageous for the first access point AP1 to successfully receive the first PPDU from the first station STA1 . Accordingly, the first access point AP1 may determine the transmit power limit based on the transmit power of the first station STA1 , the first path loss PL ₁ , and the second path loss PL _{2 .} have. For example, in the UL/DL scenario, the transmit power limit TPL _AP2 is the minimum signal required for the transmit power of the first station STA1 to be P _AP1 and the first access point AP1 to successfully receive the first PPDU. When the to-interference ratio is SIR _AP1 , the following [Equation 2] may be satisfied.

_{In some embodiments, the first station STA1 may calculate the first} pathloss PL 1 based on a frame output by the first access point AP1 , and the second access point AP2 outputs the first path loss PL 1 . _{The second path loss PL 2} may be calculated based on the frame in which The first station STA1 may _{report the first path loss PL 1} and the second path loss PL ₂ to the first access point AP1 . In addition, the first access point AP1 (or the second access point AP2) performs a third path loss PL based on a frame output by the second access point AP2 (or the first access point AP1). ₃ ) can be calculated. Accordingly, the shared access point, that is, the first access point AP1 may obtain information on the first path loss PL ₁ , the second path loss PL ₂ , and the third path loss PL ₃ . have. An example of calculating a path loss based on a received frame will be described later with reference to FIG. 12 .

8A and 8B are diagrams illustrating examples of a wireless communication system according to exemplary embodiments of the present disclosure. Specifically, the diagram of FIG. 8A shows examples of path loss considered in the DL/UL scenario of cooperative space reuse in the wireless communication system 80a, and the diagram of FIG. 8B shows the UL of cooperative space reuse in the wireless communication system 80b Shows examples of path loss considered in the /UL scenario. 8A and 8B , the first station STA1 may be included in the first BSS BSS1 provided by the first access point AP1, and the second station STA2 and the third station ( STA3) may be included in the second BSS (BSS2) provided by the second access point (AP2).

Referring to FIG. 8A , in a DL/UL scenario, a first path loss PL _11a between a first access point AP1 and a first station STA1 , a second path between a second station STA2 and the first station A loss PL _{12a and a third path loss PL 13a} between the third station STA3 and the first station STA1 may be considered. When the first path loss PL _11a is low and the second path loss PL _12a and the third path loss PL _13a are high, the first station STA1 receives the first PPDU from the first access point AP1. It can be advantageous to receive successfully. The first station STA1 may calculate a first path loss PL _11a based on a frame received from the first access point AP1 , while a second path loss PL _12a and a third path loss PL _13a ) may not be easily obtained due to the second station STA2 and the third station STA3 not outputting a frame.

Referring to FIG. 8B , in a UL/UL scenario, a first path loss (PL _11b ) between a first access point (AP1) and a first station (STA1), a first access point (AP1) and a second station (STA2) A second path loss between the PL _{12b and a third path loss PL 13b} between the first access point AP1 and the third station STA3 may be considered. When the first path loss PL _11b is low and the second path loss PL _12b and the third path loss PL _13b are high, the first access point AP1 receives the first PPDU from the first station STA1. It can be advantageous to receive successfully. The first access point AP1 may _{receive information about the first path loss PL 11b} from the first station STA1 . In addition, as will be described later with reference to FIG. 11 , the second access point AP2 transmits _{information about the second path loss PL 12b} and the third path loss PL _13b to the second station STA2 and the second access point AP2 . 3 may be received from the station STA3.

9 is a message diagram illustrating a method for collaborative space reuse according to an exemplary embodiment of the present disclosure. Specifically, the message diagram of FIG. 9 shows operations performed in the DL/UL scenario of cooperative space reuse described above with reference to FIGS. 3C and 8A . As shown in FIG. 9 , the method for collaborative space reuse may include a plurality of steps S91 to S96 . In FIG. 9 , a first station STA1 may be included in a first BSS provided by a first access point AP1 , and a second station STA2 may be included in a second BSS provided by a second access point AP2 . may be included.

As described above with reference to FIG. 8A , it may not be easy to obtain some of the necessary path losses in a DL/UL scenario of cooperative space reuse. Accordingly, in order to minimize interference with the transmission of the shared BSS (ie, the first BSS), the shared access point (ie, the second access point AP2) can conservatively determine the transmission power limit by itself. and limit the transmit power of the uplink transmission based on the determined transmit power limit. As described below, in some embodiments a shared access point may determine a transmit power limit based on received power measured from transmissions occurring in the sharing BSS.

Referring to FIG. 9 , in step S91 , the first station STA1 may transmit a PPDU to the first access point AP1 , and in step S92 , the second access point AP2 transmits the PPDU to the first station STA1 . can be received from That is, the signal output by the first station STA1 to transmit the PPDU may reach not only the first access point AP1 but also the second access point AP2, and accordingly, the second access point AP2 A PPDU may be received from the first station STA1.

In step S93, the second access point AP2 may measure the received power of the PPDU. For example, the second access point AP2 may measure the received power based on the preamble of the PPDU received in step S92. The second access point AP2 may estimate a low path loss between the second access point AP2 and the first station STA1 when the measured received power is high, while when the measured received power is high, the second access point AP2 A low path loss between the access point AP2 and the first station STA1 may be estimated. Accordingly, in some embodiments, the second access point AP2 may give up uplink transmission in the shared TXOP when the measured received power exceeds a threshold.

In operation S94 , the second access point AP2 may limit transmission power to the second station STA2 . For example, before step S94 is performed, if the TXOP may be shared by the first access point AP1 and the received power measured in step S93 is less than a threshold, the second access point AP2 may measure Based on the received received power, the minimum signal-to-interference ratio required to successfully receive the second PPDU, and the path loss between the second access point AP2 and the second station STA2, the A transmit power limit can be determined. The second access point AP2 may limit the transmit power of the second station STA2 by transmitting a signal including the determined transmit power limit to the second station STA2 .

In step S95, the first station STA1 may transmit a first PPDU to the first access point AP1 in the shared TXOP, and in step S96, the second station STA2 sends a second PPDU in the shared TXOP. 2 can be transmitted to the access point (AP2). The second station STA2 may transmit the second PPDU with a transmit power equal to or less than the transmit power limit provided from the second access point AP2 in step S94, and the first access point AP2 successfully transmits the first PPDU can receive

10 is a message diagram illustrating a method for collaborative space reuse according to an exemplary embodiment of the present disclosure. Specifically, the message diagram of FIG. 10 shows operations performed in the UL/UL scenario of cooperative space reuse described above with reference to FIGS. 3D and 8B . As shown in FIG. 10 , the method for collaborative space reuse may include a plurality of steps S91 to S96 . In FIG. 10 , a first station STA1 may be included in a first BSS provided by a first access point AP1 , and a second station STA2 may be included in a second BSS provided by a second access point AP2 . may be included. Hereinafter, FIG. 10 will be described with reference to FIG. 8B.

In step S101, the first access point AP1 may determine a tolerable interference limit (TIL). The tolerable interference limit may correspond to the maximum interference allowed for the first access point AP1 to successfully receive the first PPDU. For example, the first access point AP1 may acquire a TXOP to receive a first PPDU from the first station STA1, based on at least one loss path associated with the first access point AP1. to determine the allowable interference limit. In some embodiments, the first access point AP1 is the transmit power of the first station STA1 , the first path loss PL _11b of FIG. 8B and the minimum signal required to successfully receive the first PPDU versus An allowable interference limit may be determined based on the interference ratio. For example, the signal-to-interference ratio SIR _UL/UL of the first access point AP1 of FIG. 8B may be calculated as in Equation 3 below.

은 아래 [수학식 4]를 만족할 수 있다(SIR_UL/UL = SIR_AP1).In [Equation 3], P _STA1 , P _STA2 , and P _STA3 represent the transmission powers of the first station STA1 , the second station STA2 , and the third station STA3 , respectively. In the right-hand side of [Equation 3], the first term may correspond to the received power of the signal received by the first access point AP1 from the first station STA1, and the second term is the first access point AP1 The second term may correspond to the received power of a signal received from the second station STA2 , and the third term may correspond to the received power of the signal that the first access point AP1 receives from the third station STA3 . Accordingly, the second and third terms on the right side of [Equation 3] may correspond to interference acting on reception of the first PPDU. When the minimum signal-to-interference ratio required for the first access point AP1 to successfully receive the first PPDU is SIR _{AP1 , SIR UL/UL} in [Equation 3] may be required to be _{SIR AP1 or greater, and thus} permissible interference limits satisfying SIR _{AP1 according to}

may satisfy [Equation 4] below (SIR _UL/UL = SIR _AP1 ).

In step S102 , the first access point AP1 may provide an allowable interference limit to the second access point AP2 . For example, the first access point AP1 may transmit a signal including the allowable interference limit determined in step S101 to the second access point AP2. In some embodiments, as described below with reference to FIG. 13 , an acceptable interference limit may be included in the announcement frame.

In step S103, the second access point AP2 may identify an allowable interference limit. For example, the second access point AP2 may extract an allowable interference limit from the signal received from the first access point AP1 in step S102 .

에 기초하여, 상향링크 송신의 송신 전력 한계

는 아래 [수학식 5]를 만족할 수 있다.In step S104 , the second access point AP2 may limit the transmission power of the second station STA2 . In some embodiments, the second access point AP2 transmits the transmit power of the second station STA2 based on the tolerable interference limit identified in step S103 and the at least one path loss associated with the first access point AP1 . can be determined. For example, the allowable interference limit of [Equation 4]

Based on the transmit power limit of uplink transmission

may satisfy [Equation 5] below.

를 제2 스테이션(STA2)에 제공할 수 있다.The second access point AP2 may distribute transmit powers to stations (eg, STA2 and STA3 in FIG. 8B ) in a multi-user (MU) environment based on Equation 5, FIG. As shown in Fig. 10, in a single user environment, the transmit power limit of [Equation 5]

may be provided to the second station STA2.

In step S105, the first station STA1 may transmit a first PPDU to the first access point AP1 in the shared TXOP, and in step S106, the second station STA2 sends a second PPDU in the shared TXOP. 2 can be transmitted to the access point (AP2). The second station STA2 may transmit the second PPDU with a transmit power equal to or less than the transmit power limit provided from the second access point AP2 in step S104, and the first access point AP2 successfully transmits the first PPDU can receive

11 is a message diagram illustrating a method for cooperative space reuse according to an exemplary embodiment of the present disclosure, and FIG. 12 is a diagram illustrating a frame according to an exemplary embodiment of the present disclosure. Specifically, the message diagram of FIG. 11 shows a method of obtaining path losses used in a UL/UL scenario of cooperative spatial reuse, and the frame 120 of FIG. 12 may be used in the method of FIG. 11 . In FIG. 11 , the second station STA2 may be included in the second BSS provided by the second access point AP2 . Hereinafter, FIGS. 11 and 12 will be described with reference to FIG. 8B.

Referring to FIG. 11 , the method for cooperative space reuse may include a plurality of steps S111 to S113 . In step S111 , the first access point AP1 may transmit the frame 120 , and the second access point AP2 and the second station STA2 may receive the frame 120 , respectively. For example, each of the access points including the first access point AP1 and the second access point AP2 may output the frame 120 periodically or aperiodically, and other access points or stations They may receive the frame 120 .

Referring to FIG. 12 , a frame 120 may include a plurality of fields, and each of the plurality of fields may include information. For example, as shown in FIG. 12 , the frame 120 includes a first field 121 including information on cooperative space reuse capability and a second field including information on transmit power of the frame 120 . (122). For example, the second access point AP2 and the second station STA2 may extract the first field 121 from the frame 120 received from the first access point AP2, and the first field ( 121), it may be identified whether the first access point AP1 supports cooperative space reuse. In addition, the second access point AP1 and the second station STA2 may extract the second field 122 from the frame 120 , and based on the value of the second field 122 , the first access point ( AP1) may identify the transmit power used for transmitting the signal including the frame 120 . In some embodiments, the second field 122 may have the same format as the transmit power field included in the TPC report. The frame 120 of FIG. 12 may be any frame including the first field 121 and the second field 122 , for example, a beacon frame or a trigger frame.

Referring back to FIG. 11 , in step S112 , the second station STA2 may determine a path loss between the first access point AP1 and the second station STA2 (ie, PL _12b of FIG. 8B ). For example, the second station STA2 may measure the received power of the frame S111 , and may calculate a path loss as a difference between the measured received power and the transmit power information included in the frame 120 . In a similar manner, the path losses described above with reference to the figures may be calculated at the access point and/or station on a frame-by-frame basis.

In step S113, the second station STA2 may report a path loss. For example, the second station STA2 may transmit a signal including information about the path loss determined in step S112 to the second access point AP2. The second station STA2 may report the path loss with the first access point AP1 providing the first BSS to the second access point AP2 providing the second BSS included therein. Accordingly, as described above with reference to FIG. 10 , the second access point AP2 may determine the transmit power limit of the second station STA2 in the UL/UL scenario of cooperative space reuse.

13 is a timing diagram illustrating transmission based on cooperative space reuse according to an exemplary embodiment of the present disclosure; Specifically, the timing diagram of FIG. 12 shows an example of an announcement frame (AF) and transmissions occurring in a DL/DL scenario of cooperative spatial reuse. In FIG. 13 , a first station STA1 may be included in a first BSS provided by a first access point AP1 , and a second station STA2 may be included in a second BSS provided by a second access point AP2 . may be included.

Referring to FIG. 13 , at time t11 , the first access point AP1 may transmit a PPDU (PPDU0) including an announcement frame AF to the second access point AP2 in order to share the TXOP. The announcement frame AF may include information necessary to share the TXOP. 13 , the announcement frame AF may include a plurality of fields, and each of the plurality of fields may include information. For example, as shown in FIG. 13 , the announcement frame AF may include first to sixth fields 131 to 136 .

The first field 131 may include identification information of a shared access point (ie, the second access point AP2 ). The second field 132 may include information about the bandwidth of the shared TXOP. The third field 133 may include information on a period during which PPDU transmission is performed in the shared TXOP. The fourth field 134 may include information (eg, MSB and LSB of FIG. 5 ) indicating the type of transmission permitted to the shared access point, as described above with reference to FIG. 4 . The fifth field 135 may include a transmit power limit (TPL), as described above with reference to FIG. 6 . The sixth field 136 may include an acceptable interference limit (TIL), as described above with reference to FIG. 10 . In some embodiments, at least one of the first to sixth fields 131 to 136 illustrated in FIG. 13 may be omitted from the announcement frame AF. The shared access point may control or perform transmission of the shared BSS based on information included in the announcement frame AF.

In some embodiments, the announcement frame AF may include a plurality of fields for a plurality of shared access points. For example, as described below with reference to FIG. 16 , the first access point AP1 may share a TXOP with a plurality of shared access points including the second access point AP2 , and the plurality of shared access points may be shared. An announcement frame (AF) including information to be provided to the access points may be transmitted. Accordingly, the announcement frame AF may include a plurality of fields corresponding to each of a plurality of shared access points. For example, the announcement frame AF may include a plurality of first fields, a plurality of second fields, a plurality of third fields, and a plurality of fourth fields respectively corresponding to a plurality of shared access points. , a plurality of fifth fields and a plurality of sixth fields may be included. Also, in some embodiments, the announcement frame AF may include a field indicating information common to a plurality of shared access points. For example, the announcement frame AF may include a second field 132 and a third field 133 common to a plurality of shared access points. It is noted that fields included in the announcement frame AF for a plurality of shared access points may be variously combined, and the configuration of the announcement frame AF is not limited to the above.

At time t12, the first access point AP1 may transmit a first PPDU (PPDU1) in the shared TXOP to the first station STA1, and the second access point AP2 may transmit a second PPDU in the shared TXOP (PPDU2) may be transmitted to the second station STA2. As described above with reference to FIG. 6 , the second access point AP2 may transmit the second PPDU PPDU2 with limited transmission power. Accordingly, the first station STA1 and the second station STA2 may successfully receive the first PPDU (PPDU1) and the second PPDU (PPDU2) in the shared TXOP, respectively, and the first acknowledgment at time t13 (BA1) and the second acknowledgment BA2 may be transmitted to the first access point AP1 and the second access point AP2, respectively.

14 is a timing diagram illustrating transmission based on cooperative space reuse according to an exemplary embodiment of the present disclosure. Specifically, the timing diagram of FIG. 14 shows the transmission occurring in the UL/DL scenario of cooperative spatial reuse. In FIG. 14 , first stations STA11 and STA12 may be included in a first BSS provided by a first access point AP1 , and a second station STA2 may include a second station provided by a second access point AP2 . 2 may be included in the BSS.

Referring to FIG. 14 , at time t21 , the first access point AP1 may transmit the PPDU PPDU0 including the announcement frame AF to the second access point AP2 . For example, the first access point AP1 may acquire a TXOP to receive the first PPDUs PPDU11 and PPDU12, and transmit an announcement frame AF to a second access to share the acquired TXOP. It can transmit to the point AP2.

At time t22, the first access point AP1 may transmit a PPDU 10 including a trigger frame TF to the first stations STA11 and STA12, and the second access point AP2 may transmit the second The PPDU (PPDU2) may be transmitted to the second station STA2. At time t23, the first stations STA11 and STA12 may transmit the first PPDUs PPDU11 and PPDU12 to the first access point AP1 in response to the trigger frame TF.

The first access point (AP1) generated an announcement frame (AF) based on the UL / DL scenario of cooperative spatial reuse, but as shown in FIG. 14 , including a trigger frame (TF) in the shared TXOP The transmission of the PPDU (PPDU10) and the transmission of the second PPDU (PPDU2) may overlap. In order to eliminate overlap, when the second access point AP2 delays the transmission of the second PPDU (PPDU2) to time t23, the transmissions of the first PPDUs PPDU11, PPDU12 and the second PPDU2 are successful. , but the completion of transmissions in the shared TXOP may be delayed. With reference to FIGS. 15A and 15B , in a UL/DL scenario of cooperative space reuse, a method for successfully performing transmissions without delaying the completion of transmissions will be described below.

15A and 15B are timing diagrams illustrating transmission based on cooperative space reuse according to example embodiments of the present disclosure. Specifically, each of the timing diagrams of FIGS. 15A and 15B represent transmissions occurring in a UL/DL scenario of cooperative spatial reuse. 15A and 15B , first stations STA11 and STA12 may be included in a first BSS provided by a first access point AP1, and a second station STA2 may include a second access point AP2. It may be included in the second BSS provided. Duplicate content in the description of FIGS. 15A and 15B will be omitted.

Referring to FIG. 15A , at time t31, the first access point AP1 may transmit a PPDU0 including the announcement frame AF to the second access point AP2 and the first stations STA11 and STA12. In addition, the trigger information field 151 of the announcement frame AF may include the trigger information field 151 . For example, the announcement frame AF includes at least one of a common information field and at least a portion of a user information field included in the trigger frame TF of FIG. 14 . It may include subfields. Accordingly, transmission of a separate PPDU including the trigger frame may be omitted, and as a result, transmissions may be successfully completed early in the UL/DL scenario of cooperative space reuse.

At time t32, the first stations STA11 and STA12 may transmit the first PPDUs PPDU11 and PPDU12 in the shared TXOP to the first access point AP1, and the second access point AP2 may share the shared TXOP. In the TXOP, the second PPDU (PPDU2) may be transmitted to the second station STA2. For example, the first stations STA11 and STA12 may obtain information for uplink transmission based on the value of the trigger information field 151 of the announcement frame AF, and based on the obtained information Thus, the first PPDUs PPDU11 and PPDU12 may be transmitted to the first access point AP1. Transmissions of the first PPDUs (PPDU11, PPDU12) and the second PPDU (PPDU2) may be successfully completed, and accordingly, at time t33, the first access point AP1 sends a first acknowledgment BA1 to the first may transmit to the stations STA11 and STA12 , and the second access point AP2 may transmit a second acknowledgment BA2 to the second station STA2 .

15B, at time t41, the first access point AP1 transmits a PPDU (PPDU0) including an announcement frame AF and a trigger frame TF to the first stations STA11 and STA12 and the second It can transmit to the access point (AP2). For example, the announcement frame AF and the trigger frame TF may be aggregated in the PPDU (PPDU0). In some embodiments, the PPDU (PPDU0) including the aggregated announcement frame AF and the trigger frame TF may have the format of an aggregated MAC protocol data unit (A-MPDU). Accordingly, transmission of a separate PPDU including the trigger frame may be omitted, and as a result, transmissions may be successfully completed early in the UL/DL scenario of cooperative space reuse.

At time t42, the first stations STA11 and STA12 may transmit the first PPDUs PPDU11 and PPDU12 in the shared TXOP to the first access point AP1, and the second access point AP2 may share the shared TXOP. In the TXOP, the second PPDU (PPDU2) may be transmitted to the second station STA2. Then at time t33 , the first access point AP1 may transmit a first acknowledgment BA1 to the first stations STA11 , STA12 , and the second access point AP2 sends a second acknowledgment (BA2) may be transmitted to the second station STA2.

16 is a diagram illustrating a wireless communication system 160 according to an exemplary embodiment of the present disclosure. As shown in FIG. 16 , the wireless communication system 160 may include first to fifth access points AP11 to AP15 .

In some embodiments, a sharing access point may share a TXOP with a plurality of shared access points. For example, when the first access point AP11 obtains a TXOP to transmit a PPDU, the first access point AP11 transmits an announcement frame to the second to fifth access points among the neighboring access points. (AP12 to AP15) can share a TXOP. In some embodiments, the first access point AP11 may permit uplink transmission and/or downlink transmission to each of the second to fifth access points AP12 to AP15. In some embodiments, the first access point AP11 may provide a transmit power limit and/or an acceptable interference limit to each of the second to fifth access points AP12 to AP15 . Accordingly, various scenarios of cooperative space reuse can be implemented, and as a result, the efficiency of the wireless communication system 160 can be significantly increased.

In some embodiments, the sharing access point may allocate radio resources used for transmissions of the plurality of shared access points. For example, when the first access point AP11 obtains a TXOP to transmit a PPDU, the first access point AP11 provides a higher bandwidth to the second access point AP12 and the fifth access point AP15. A band may be allocated, and a lower bandwidth of the bandwidth may be allocated to the third access point AP13 and the fourth access point AP14. To this end, the first access point AP11 may transmit an announcement frame including resource allocation information, that is, bandwidth allocation information, and each of the second to fifth access points AP12 to AP15 announces. A band may be identified based on allocation information of a band included in the data frame, and a PPDU may be transmitted to at least one station in the identified band.

17 is a diagram illustrating examples of an apparatus for wireless communication according to an exemplary embodiment of the present disclosure. Specifically, FIG. 17 shows an Internet of Things (IoT) network system including a home device 171 , a home appliance 172 , an entertainment device 173 , and an access point 175 .

In some embodiments, in the apparatus for wireless communication of FIG. 17 , the method for cooperative space reuse described above with reference to the drawings may be performed. For example, an access point 175 (ie, a shared access point) that has obtained a TXOP may share a TXOP with a neighboring access point (ie, a shared access point), and the home appliance 171 in the shared TXOP , may transmit a PPDU to the home appliance 172 and/or the entertainment device 173 , or receive a PPDU from the home appliance 171 , the home appliance 172 and/or the entertainment device 173 . In some embodiments, home device 171 , appliance 172 , and/or entertainment device 173 may report at least one path loss to access point 175 . As described above with reference to the drawings, various scenarios of collaborative space reuse can be supported, so that the home device 171 , the home appliance 172 and/or the entertainment device 173 can successfully transmit or receive a PPDU. At the same time, the neighboring access points and stations may not delay transmission of the PPDU, and as a result, the efficiency of the IoT network system may be increased.

Exemplary embodiments have been disclosed in the drawings and specification as described above. Although embodiments have been described using specific terms in the present specification, these are used only for the purpose of explaining the technical idea of the present disclosure and not used to limit the meaning or the scope of the present disclosure described in the claims. . Therefore, it will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible therefrom. Accordingly, the true technical protection scope of the present disclosure should be defined by the technical spirit of the appended claims.

Claims (20)

A wireless communication method performed by a first device, comprising:
acquiring a transmit opportunity (TXOP) to transmit or receive a first physical layer protocol data unit (PPDU);
identifying a second device to share the TXOP;
permitting at least one of transmission and reception of a second PPDU to the second device in the shared TXOP; and
and transmitting the first PPDU to or receiving from the at least one third device in the shared TXOP. The method according to claim 1,
The step of permitting at least one of transmission and reception of the second PPDU comprises providing information indicating the permitted transmission and/or permitted reception of the second PPDU to the second device. wireless communication method. The method according to claim 1,
The step of allowing at least one of transmission and reception of the second PPDU includes allowing transmission of the second PPDU,
The method of claim 1, wherein permitting the transmission of the second PPDU includes providing a transmit power limit of the transmission of the second PPDU to the second device. 4. The method according to claim 3,
obtaining information about at least one path loss; and
and determining the transmit power limit based on the at least one path loss. 5. The method according to claim 4,
The step of obtaining information about the at least one path loss comprises:
receiving, from a third device, information about a first path loss between the first device and the third device; and
and receiving, from the second device, information on a second path loss between the second device and the third device. 5. The method according to claim 4,
The step of obtaining information about the at least one path loss comprises:
receiving, from a third device, information about a first path loss between the first device and the third device; and
and determining a third path loss between the first device and the second device based on a frame received from the second device. 7. The method of claim 6,
The step of determining the third path loss comprises:
extracting transmit power information from the frame;
measuring the received power of the frame; and
and calculating the third path loss based on the transmitted power information and the measured received power. The method according to claim 1,
The step of permitting at least one of transmission and reception of the second PPDU includes permitting reception of the second PPDU,
The step of allowing reception of the second PPDU includes:
and providing a tolerable interference limit of transmission or reception of the first PPDU to the second device. 9. The method of claim 8,
obtaining information about at least one path loss; and
and determining the tolerable interference limit based on the at least one path loss. 10. The method of claim 9,
Obtaining the information on the at least one path loss includes receiving, from a third device, information on the first path loss between the first device and the third device,
The determining of the allowable interference limit is based on the transmission power of the first PPDU and the first path loss. The method according to claim 1,
The step of allowing at least one of transmission and reception of the second PPDU includes allowing only the transmission of the second PPDU. The method according to claim 1,
The step of allowing at least one of transmission and reception of the second PPDU includes transmitting an announcement frame to the second device. 13. The method of claim 12,
When the TXOP is obtained to receive the first PPDU, the announcement frame includes information included in a trigger frame for reception of the first PPDU,
The wireless communication method, characterized in that the transmission of the trigger frame to the at least one third device is omitted. 13. The method of claim 12,
When the TXOP is obtained to receive the first PPDU, the method further comprising: transmitting a trigger frame to the at least one third device;
The announcement frame and the trigger frame, the wireless communication method, characterized in that the aggregate (aggregated) in one PPDU. A wireless communication method performed by a second device sharing a transmit opportunity (TXOP) with a first device, the method comprising:
receiving, from the first device that has obtained the TXOP to transmit or receive a first physical layer data unit (PPDU), a permission for spatial reuse;
identifying at least one of transmission and reception of a second PPDU based on the permission for spatial reuse; and
and transmitting the second PPDU to or from the at least one third device in the shared TXOP. 16. The method of claim 15,
Receiving a transmit power limit of the transmission of the second PPDU from the first device,
The transmitting or receiving of the second PPDU includes transmitting the second PPDU to the at least one third device with a transmit power equal to or less than the transmit power limit. 16. The method of claim 15,
receiving a tolerable interference limit of transmission or reception of the first PPDU from the first device; and
and limiting the transmission power of the at least one third device based on the allowable interference limit when the reception of the second PPDU is identified. 16. The method of claim 15,
receiving at least one PPDU from the first device and at least one device associated with the first device; and
Based on the received power of the at least one PPDU, the wireless communication method further comprising the step of limiting the transmission power of the at least one third device. A wireless communication method performed by a third device associated with the second device in a transmit opportunity (TXOP) shared by a first device and a second device, the method comprising:
receiving a frame from the first device;
determining a path loss between the first device and the third device based on the frame;
transmitting information on the path loss to the second device; and
and receiving, in the shared TXOP, a physical layer protocol data unit (PPDU) from or transmitting to the second device. 20. The method of claim 19,
The step of determining the path loss comprises:
extracting transmit power information from the frame;
measuring the received power of the frame; and
and calculating the path loss based on the transmitted power information and the measured received power.

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