WO2021004404A1 - 通信保护方法及装置 - Google Patents

通信保护方法及装置 Download PDF

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Publication number
WO2021004404A1
WO2021004404A1 PCT/CN2020/100269 CN2020100269W WO2021004404A1 WO 2021004404 A1 WO2021004404 A1 WO 2021004404A1 CN 2020100269 W CN2020100269 W CN 2020100269W WO 2021004404 A1 WO2021004404 A1 WO 2021004404A1
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WIPO (PCT)
Prior art keywords
link
entity
ppdu
value
nav
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PCT/CN2020/100269
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English (en)
French (fr)
Inventor
李云波
淦明
杨懋
闫中江
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华为技术有限公司
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Application filed by 华为技术有限公司 filed Critical 华为技术有限公司
Priority to BR112021026902A priority Critical patent/BR112021026902A2/pt
Priority to EP20837740.8A priority patent/EP3982687A4/en
Priority to KR1020227001904A priority patent/KR20220024738A/ko
Priority to JP2021577203A priority patent/JP7255950B2/ja
Publication of WO2021004404A1 publication Critical patent/WO2021004404A1/zh
Priority to US17/646,962 priority patent/US11665264B2/en

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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W74/00—Wireless channel access, e.g. scheduled or random access
    • H04W74/08—Non-scheduled or contention based access, e.g. random access, ALOHA, CSMA [Carrier Sense Multiple Access]
    • H04W74/0833—Non-scheduled or contention based access, e.g. random access, ALOHA, CSMA [Carrier Sense Multiple Access] using a random access procedure
    • H04W74/0841—Non-scheduled or contention based access, e.g. random access, ALOHA, CSMA [Carrier Sense Multiple Access] using a random access procedure with collision treatment
    • H04W74/085—Non-scheduled or contention based access, e.g. random access, ALOHA, CSMA [Carrier Sense Multiple Access] using a random access procedure with collision treatment collision avoidance
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W74/00—Wireless channel access, e.g. scheduled or random access
    • H04W74/08—Non-scheduled or contention based access, e.g. random access, ALOHA, CSMA [Carrier Sense Multiple Access]
    • H04W74/0808—Non-scheduled or contention based access, e.g. random access, ALOHA, CSMA [Carrier Sense Multiple Access] using carrier sensing, e.g. as in CSMA
    • H04W74/0816—Non-scheduled or contention based access, e.g. random access, ALOHA, CSMA [Carrier Sense Multiple Access] using carrier sensing, e.g. as in CSMA carrier sensing with collision avoidance
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L69/00—Network arrangements, protocols or services independent of the application payload and not provided for in the other groups of this subclass
    • H04L69/14—Multichannel or multilink protocols
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L69/00—Network arrangements, protocols or services independent of the application payload and not provided for in the other groups of this subclass
    • H04L69/30—Definitions, standards or architectural aspects of layered protocol stacks
    • H04L69/32—Architecture of open systems interconnection [OSI] 7-layer type protocol stacks, e.g. the interfaces between the data link level and the physical level
    • H04L69/322—Intralayer communication protocols among peer entities or protocol data unit [PDU] definitions
    • H04L69/323—Intralayer communication protocols among peer entities or protocol data unit [PDU] definitions in the physical layer [OSI layer 1]
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L69/00—Network arrangements, protocols or services independent of the application payload and not provided for in the other groups of this subclass
    • H04L69/30—Definitions, standards or architectural aspects of layered protocol stacks
    • H04L69/32—Architecture of open systems interconnection [OSI] 7-layer type protocol stacks, e.g. the interfaces between the data link level and the physical level
    • H04L69/322—Intralayer communication protocols among peer entities or protocol data unit [PDU] definitions
    • H04L69/324—Intralayer communication protocols among peer entities or protocol data unit [PDU] definitions in the data link layer [OSI layer 2], e.g. HDLC
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W74/00—Wireless channel access, e.g. scheduled or random access
    • H04W74/02—Hybrid access techniques
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W74/00—Wireless channel access, e.g. scheduled or random access
    • H04W74/04—Scheduled or contention-free access
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W76/00—Connection management
    • H04W76/10—Connection setup
    • H04W76/15—Setup of multiple wireless link connections
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W84/00—Network topologies
    • H04W84/02—Hierarchically pre-organised networks, e.g. paging networks, cellular networks, WLAN [Wireless Local Area Network] or WLL [Wireless Local Loop]
    • H04W84/10—Small scale networks; Flat hierarchical networks
    • H04W84/12—WLAN [Wireless Local Area Networks]

Definitions

  • This application relates to the field of communication technology, and in particular to communication protection methods and devices.
  • the Institute of Electrical and Electronics Engineers (IEEE) 802.11be standard takes multi-link (ML) as one of the key technologies.
  • ML multi-link
  • the ML entity supporting the ML technology has the ability to send and receive in multiple frequency bands, so that the ML entity can use a larger bandwidth for data transmission, which is beneficial to significantly improve the throughput rate.
  • the spatial path through which the ML entity performs data transmission on a frequency band can be referred to as a link.
  • the present application provides a communication protection method and device, which are used to solve the problem of asynchronous reception and transmission of ML entities on multiple links.
  • a communication protection method is provided, which is applied to an ML entity, and the ML entity supports multiple links.
  • the method includes: the ML entity listens to the first physical layer protocol data unit (PPDU) on the first link; if the first PPDU is an intra-BSS PPDU, and the first If the value of the duration field of the PPDU is greater than the value of the target NAV of the second link, the ML entity updates the value of the target network allocation vector (NAV) of the second link to the duration field of the first PPDU
  • NAV target network allocation vector
  • the ML entity listens to the first PPDU sent by other intra-BSS stations on the first link, and the value of the duration field of the first PPDU is greater than the value of the target NAV of the second link .
  • the ML entity updates the value of the target NAV of the second link to the value of the duration field of the first PPDU, so as to ensure that after the first PPDU is transmitted, the ML entity is PPDU will not be sent within the duration, which will not cause other ML entities in the same BSS to receive PPDUs on one link and send PPDUs on another link at the same time, that is, to ensure that other ML entities are in multiple chains Simultaneously send/receive signals on the road.
  • the method further includes: if the first PPDU is an inter-BSS PPDU, the ML entity does not update the value of the target NAV of the second link; or, if the first PPDU is intra-BSS PPDU, and the value of the duration field of the first PPDU is less than or equal to the value of the target NAV of the second link, the ML entity does not update the value of the target NAV of the second link.
  • the method further includes: the ML entity listens to a contention-free end (CF-End) frame on the first link; if the CF-end frame is an intra-BSS PPDU, and The value of the target NAV of the second link is updated according to the value of the duration field of the first PPDU, and the ML entity sets the value of the target NAV of the second link to 0. It should be understood that the target NAV of the second link of the ML entity is updated according to the value of the duration field of the first PPDU heard on the first link, so as to ensure that the ML entity does not send data on the second link and avoid impact Communication of other ML entities in the same BSS on the first link.
  • CF-End contention-free end
  • the ML entity listens to the CF-End frame in the same BSS on the first link, it means that the communication of other ML entities in the same BSS on the first link has ended, so the ML entity can
  • the value of the target NAV is set to 0, so that the virtual carrier monitoring of the ML entity on the second link is not affected by the communication on the first link, avoiding delays in channel competition of the ML entity on the second link, which is beneficial Improve the ML entity's utilization of the second link.
  • the method further includes: if the ML entity does not hear the second PPDU within a preset period of time on the first link, and the value of the target NAV of the second link is based on the first PPDU If the value of the duration field is updated, the ML entity resets the target NAV of the second link, and the second PPDU and the first PPDU are from the same station. It should be understood that if the ML entity does not hear the second PPDU sent by the sender of the first PPDU on the first link within the preset time period, it means that the sender of the first PPDU may not be occupied on the first link. Therefore, the ML entity can initiate channel competition on the first link to send the first PPDU on the first link.
  • the ML entity if the target NAV is updated according to the value of the duration field of the first PPDU, the ML entity resets the target NAV so that the virtual carrier monitoring of the ML entity on the second link is not affected.
  • the influence of the communication on the first link avoids delaying the channel competition of the ML entity on the second link, which is beneficial to improve the utilization rate of the ML entity on the second link.
  • the ML entity resets the target NAV of the second link, including: the ML entity sets the target NAV value of the second link to 0; or the ML entity sets the target NAV value of the second link It is the first value, the end time determined by the first value is the same as the end time determined by the second value, and the second value is the value of the target NAV before the target NAV is updated according to the value of the duration field of the first PPDU.
  • the preset duration (2 ⁇ aSIFSTime)+(the transmission duration of the first PPDU response frame)+aRxPHYStartDelay+(2 ⁇ aSlotTime).
  • aSIFSTime represents the duration of a short inter-frame space (SIFS)
  • aRxPHYStartDelay represents the duration of a preset delay
  • aSlotTime represents the duration of a time slot.
  • a request to send (RTS) frame is carried in the first PPDU, and the response frame is a clear to send (CTS) frame.
  • RTS request to send
  • CTS clear to send
  • the target NAV includes one of the following situations: (1) If the ML non-AP entity is on the second link If intra-BSS NAV and basic NAV are configured on the above, the target NAV is intra-BSS NAV; (2) If the ML non-AP entity is configured with intra-BSS NAV, basic NAV, and the first NAV on the second link , The target NAV is the first NAV.
  • the target NAV includes one of the following situations: (1) If the ML AP entity is configured with intra-BSS on the second link NAV and basic NAV, the target NAV is intra-BSS NAV; (2) If the ML AP entity is only configured with intra-BSS NAV, basic NAV and the first NAV on the second link, the target NAV is the first NAV; (3) If the ML AP entity is configured with the first NAV and the second NAV on the second link, the target NAV is the first NAV.
  • AP ML access point
  • a communication protection method is provided, which is applied to an ML entity, and the ML entity supports multiple links.
  • the method includes: the ML entity sends a first PPDU on a first link, the first PPDU includes a duration field, and the duration field included in the first PPDU is used to indicate the duration of the first period; the ML entity is on the second link
  • the MAC frame is sent on the Internet.
  • the media access control (MAC) frame is used to indicate the duration of the second period.
  • the end time of the first period is the same as the end time of the second period.
  • the intra-BSS site is prohibited from sending the second PPDU, and the second link is any one of the multiple links supported by the ML entity except the first link.
  • the ML entity when the ML entity sends a PPDU on the first link, the ML entity sends a MAC frame on the second link, so that other stations in the same BSS on the second link at the end of the first period PPDU will not be sent before. In this way, it is guaranteed that the ML entity will not send PPDUs on the first link and receive PPDUs on the second link, and it is guaranteed that the ML entity can synchronously send/receive signals on multiple links.
  • the MAC frame is an announcement frame or a quiet time period (quiet time period, QTP) frame.
  • the value of the duration field of the announcement frame is equal to the duration of the second period, and the duration field of the announcement frame is used to set the value of NAV maintained by the intra-BSS site, and the duration field of the announcement frame It is not used to set the value of NAV maintained by the site of the overlapping basic service set (OBSS).
  • OBSS overlapping basic service set
  • the announcement frame includes a duration field and a duration field.
  • the duration field is used to set the value of the NAV maintained by the intra-BSS site.
  • the value of the duration field is 0, and the value of the duration field is equal to the first The duration of the second period.
  • a communication protection method is provided, which is applied to an ML entity, and the ML entity supports multiple links.
  • the method includes: the ML entity listens to the start of the PPDU on the first link; the ML entity stops counting the first backoff counter on the second link, and the second link is among the multiple links supported by the ML entity Any link except the first link; the ML entity judges whether the PPDU is an intra-BSS PPDU or an inter-BSS PPDU; if the PPDU is an intra-BSS PPDU, the ML entity is in the second link after the PPDU transmission is completed Continue to fall back on the road; if the PPDU is an inter-BSS PPDU, the ML entity continues to fall back on the second link.
  • the ML entity suspends the counting of the first backoff counter on the second link.
  • the ML entity does not continue to roll back until the PPDU is transmitted. Therefore, during the PPDU transmission process on the first link, the ML entity will not send PPDUs on the second link, so as to avoid causing other ML entities in the same BSS to receive signals on the first link and receive signals on the other link. The condition of sending signals on the link.
  • the ML entity determines that the PPDU is an inter-BSS PPDU, the ML entity immediately continues to roll back, thereby ensuring that the ML entity can normally perform channel access on the second link.
  • the ML entity continues to fall back on the second link after the PPDU transmission is completed, including: the ML entity continues to fall back on the second link after the first moment, and the first moment is the PPDU The transmission end time of the ML entity; or, the ML entity continues to fall back on the second link after the second time, and the second time is the transmission end time of the response frame corresponding to the PPDU; or, the ML entity is after the third time, Backoff continues on the second link, and the third moment is the end moment determined by the duration field of the PPDU.
  • the method further includes: the ML entity configures a second backoff counter on the second link, and the initial value of the second backoff counter The value is the current value of the first backoff counter; if the second link is in the idle state at the current moment, the ML entity will decrement the count value of the second backoff counter every time the second link is idle in a time slot 1; If the second link is busy at the current moment, the ML entity waits for the idle time of the second link to reach the second inter-frame interval; after the idle time of the second link reaches the second inter-frame interval, whenever The second link is in an idle state in one time slot, and the ML entity decrements the count value of the second backoff counter by 1.
  • the method further includes: after the count value of the second backoff counter is reduced to 0, the ML entity maintains the count value of the second backoff counter to 0.
  • the method further includes: when the count value of the second backoff counter decreases to 0, the ML entity resets the count value of the second backoff counter.
  • the ML entity resets the count value of the second backoff counter, including: the ML entity resets the count value of the second backoff counter according to the doubled contention window; or, the ML entity resets the count value of the second backoff counter according to the contention window The count value of the second backoff counter; or, the ML entity resets the count value of the second backoff counter according to the minimum value of the contention window.
  • the ML entity continues to fall back on the second link, including: if the PPDU is an inter-BSS PPDU, the ML entity is updated with the count value of the second backoff counter Based on the count value of the first backoff counter, the backoff continues on the second link based on the first backoff counter. Based on this design, when the ML entity determines that the PPDU is an inter-PPDU, the ML entity then sets the count value of the first backoff counter with the count value of the second backoff counter, so that the first backoff counter is not affected by the previous suspension.
  • the PPDU is an inter-BSS PPDU
  • the backoff process of the ML entity on the second link is not affected, thereby avoiding the ML entity being at a disadvantage in channel competition and ensuring that the ML entity is Use of roads.
  • a communication protection method is provided, which is applied to an ML non-AP entity, and the ML non-AP entity supports multiple links.
  • the method includes: the ML non-AP entity listens to the first PPDU on the first link; if the receiving end of the first PPDU is the ML AP entity associated with the ML non-AP entity, the ML non-AP entity is in the first link
  • the second PPDU is sent on the second link.
  • the second link is any one of the multiple links supported by the ML non-AP entity except the first link.
  • the end time of the first PPDU is the same as the second PPDU. The end moment is the same.
  • the ML non-AP entity listens to the first PPDU on the first link, and the first PPDU is sent to the ML AP entity associated with the ML non-AP entity, then the ML non-AP entity The second PPDU is sent on the second link. Since the end time of the second PPDU is the same as the end time of the first PPDU, the ML AP entity can send the block acknowledgment (BA) frame of the second PPDU and the BA frame of the first PPDU at the same time. In this way, on the one hand, the situation where the ML AP entity sends signals on one link and receives signals on another link is avoided. On the other hand, the ML non-AP entity sends the second PPDU on the second link, which helps to improve the utilization of the second link.
  • BA block acknowledgment
  • the ML non-AP entity sends the second PPDU on the second link, including: the ML non-AP entity performs the backoff process on the second link; the backoff process on the second link ends After that, the ML non-AP entity sends the second PPDU on the second link.
  • an ML entity may include a module for performing a one-to-one correspondence of the method/operation/step/action described in any one of the designs of the first aspect to the fourth aspect.
  • the above-mentioned modules may be hardware circuits, or software, or implemented by hardware circuits combined with software.
  • an ML entity in a sixth aspect, includes a processor and a transceiver, and the processor is configured to execute any one of the communication protection methods involved in the design of the first to fourth aspects. Processing operation.
  • the transceiver is used to accept the control of the processor to perform the transceiver operations in the communication protection method involved in any of the designs of the first aspect to the fourth aspect.
  • a computer-readable storage medium is provided.
  • the computer-readable storage medium is used to store instructions.
  • the instructions are read by a computer, the computer is used to execute any of the above-mentioned designs in the first to fourth aspects.
  • the communication protection method involved.
  • a computer program product includes instructions.
  • the computer reads the instruction, the computer executes the communication protection method involved in any one of the above-mentioned first to fourth aspects.
  • a chip in a ninth aspect, includes a processing circuit and a transceiver pin.
  • the chip supports multiple links.
  • the transceiver pin is used to listen to the first PPDU on the first link.
  • the processing circuit is used to convert the target NAV value of the second link when the first PPDU is an intra-BSS PPDU and the value of the duration field of the first PPDU is greater than the value of the target NAV of the second link Update to the value of the duration field of the first PPDU, and the second link is any one of the multiple links supported by the ML entity except the first link.
  • a chip in a tenth aspect, includes a processing circuit and transceiver pins.
  • the chip supports multiple links.
  • the transceiver pin is used to send the first PPDU on the first link, the first PPDU includes a duration field, and the duration field included in the first PPDU is used to indicate the duration of the first period.
  • the transceiver pins are also used to send MAC frames on the second link.
  • the MAC frames are used to indicate the duration of the second period.
  • the end time of the first period is the same as the end time of the second period.
  • the second link in the second period The intra-BSS station on the road is prohibited from sending the second PPDU, and the second link is any one of the multiple links supported by the ML entity except the first link.
  • a chip which includes a processing circuit and a transceiver pin.
  • the chip supports multiple links.
  • the transceiver pin is used to detect the beginning of the PPDU on the first link.
  • the processing circuit is used to stop the counting of the first backoff counter on the second link, and determine whether the PPDU is an intra-BSS PPDU or an inter-BSS PPDU; in the case of an intra-BSS PPDU, after the PPDU transmission is completed , Continue to fall back on the second link; if the PPDU is an inter-BSS PPDU, continue to fall back on the second link.
  • the second link is any one of the multiple links supported by the chip except the first link.
  • a chip in a twelfth aspect, includes a processing circuit and transceiver pins.
  • the chip supports multiple links, and the transceiver pins are used to listen to the first PPDU on the first link.
  • the transceiver pins are also used to send the second PPDU on the second link when the receiving end of the first PPDU is the associated ML AP entity, and the second link is multiple supported by the ML non-AP entity For any link in the link except the first link, the end time of the first PPDU is the same as the end time of the second PPDU.
  • the technical effects brought by any one of the designs of the fifth aspect to the twelfth aspect can refer to the beneficial effects in the corresponding method provided above, which will not be repeated here.
  • FIG. 1 is a schematic diagram of a backoff process provided by an embodiment of this application.
  • Figure 2 is a schematic diagram of a PPDU frame structure provided by an embodiment of the application.
  • FIG. 3 is a schematic diagram of a communication scenario between ML entities provided by an embodiment of this application.
  • FIG. 4 is a schematic diagram of an ML communication scenario provided by an embodiment of the application.
  • FIG. 5 is a schematic diagram of another ML communication scenario provided by an embodiment of the application.
  • FIG. 6 is a flowchart of a communication protection method provided by an embodiment of this application.
  • FIG. 7 is a schematic diagram of another ML communication scenario provided by an embodiment of the application.
  • FIG. 8 is a flowchart of another communication protection method provided by an embodiment of this application.
  • FIG. 9 is a flowchart of another communication protection method provided by an embodiment of this application.
  • FIG. 10 is a flowchart of another communication protection method provided by an embodiment of this application.
  • FIG. 11 is a schematic diagram of a frame structure of an announcement frame provided by an embodiment of the application.
  • FIG. 12 is a schematic diagram of a frame structure of an announcement frame provided by an embodiment of the application.
  • FIG. 13 is a schematic diagram of a frame structure of a frame announcement frame provided by an embodiment of the application.
  • FIG. 14 is a schematic diagram of another ML communication scenario provided by an embodiment of the application.
  • FIG. 15 is a flowchart of another communication protection method provided by an embodiment of this application.
  • FIG. 16(a) is a schematic diagram of another ML communication scenario provided by an embodiment of this application.
  • FIG. 16(b) is a schematic diagram of another ML communication scenario provided by an embodiment of this application.
  • FIG. 16(c) is a schematic diagram of another ML communication scenario provided by an embodiment of this application.
  • FIG. 16(d) is a schematic diagram of another ML communication scenario provided by an embodiment of this application.
  • FIG. 16(e) is a schematic diagram of another ML communication scenario provided by an embodiment of this application.
  • Figure 16(f) is a schematic diagram of another ML communication scenario provided by an embodiment of this application.
  • Figure 16(g) is a schematic diagram of another ML communication scenario provided by an embodiment of the application.
  • FIG. 17 is a flowchart of another communication protection method provided by an embodiment of this application.
  • FIG. 19 is a flowchart of a communication protection method provided by an embodiment of this application.
  • FIG. 21 is a schematic structural diagram of an ML entity provided by an embodiment of this application.
  • FIG. 22 is a schematic structural diagram of an ML entity provided by an embodiment of this application.
  • A/B can mean A or B.
  • the "and/or” in this article is only an association relationship describing the associated objects, which means that there can be three relationships, for example, A and/or B, which can mean: A alone exists, A and B exist at the same time, and B exists alone These three situations.
  • “at least one” means one or more
  • “plurality” means two or more. The words “first” and “second” do not limit the quantity and order of execution, and the words “first” and “second” do not limit the difference.
  • BSS Basic service set
  • BSS is used to describe a group of devices that can communicate with each other in wireless local area networks (WLAN). Multiple BSSs can be included in the WLAN. Each BSS has a unique identification, which is called a basic service set identifier (BSSID).
  • BSSID basic service set identifier
  • One BSS may include multiple stations (stations, STAs).
  • the station includes AP and non-access point station (none access point station, non-AP STA).
  • one BSS may include one AP and multiple non-AP STAs associated with the AP.
  • the APs are also called wireless access points or hotspots.
  • the AP can be a wireless router, wireless transceiver, wireless switch, and so on.
  • the non-AP STA can have different names, such as subscriber unit, access terminal, mobile station, mobile station, mobile device, terminal, user equipment, etc.
  • STAs can be cellular phones, smart phones, wireless local loops (WLL), and other handheld devices and computer devices with wireless local area network communication functions.
  • WLL wireless local loops
  • the IEEE 802.11 standard supports multiple users sharing the same transmission medium, and the sender checks the availability of the transmission medium before sending data.
  • the IEEE 802.11 standard adopts carrier sense multiple access/collision avoidance (carrier sense multiple access with collision avoidance, CSMA/CA) to achieve channel competition. Among them, in order to avoid collisions, CSMA/CA uses a back-off mechanism.
  • the device Before the device sends the message, the device can select a random number from 0 to the contention window (CW), and use the random number as the initial value of the backoff counter. After the idle time of the channel reaches the arbitration interframe space (AIFS), when the channel is idle for each time slot (timeslot), the count value of the backoff counter is reduced by one. Before the count value of the backoff counter is reduced to 0, if the channel is busy in a certain timeslot, the backoff counter suspends counting. After that, if the channel changes from the busy state to the idle state, and the idle time of the channel reaches AIFS, the backoff counter resumes counting. When the count value of the backoff counter is 0, the backoff process ends and the device can start data transmission.
  • AIFS arbitration interframe space
  • the backoff counter starts to back off. Whenever the channel is in an idle state in a time slot, the count value of the backoff counter is reduced by 1 until the count value of the backoff counter is 0. After the count value of the backoff counter is 0, the device can send PPDUs on the channel.
  • NAV is used in virtual carrier monitoring
  • NAV is equivalent to a counter, used to record the time occupied by the station on the channel.
  • the NAV value will continue to decrease over time, but before the NAV value is reduced to zero, the station always considers the channel busy and stops channel contention and data transmission.
  • non-AP STA has two NAVs, intra-NAV and basic NAV.
  • intra-NAV is updated according to intra-BSS PPDU.
  • Basic NAV is updated based on inter-BSS PPDU, or based on PPDUs that cannot be classified as intra-BSS or inter-BSS.
  • the AP can have two NAVs or only one AP.
  • the two NAVs of the AP are intra-NAV and basic NAV.
  • the station can protect the frames sent by the intra-BSS station, and can also avoid interference from the frames sent by the inter-BSS station.
  • PPDU includes: traditional short training field (legacy-short training field, L-STF), traditional long training field (legacy-long training field, L-LTF), traditional signaling field (legacy-signal field, L-SIG), Repeating traditional signaling field (repeated legacy-signal field, RL-SIG), high efficiency-signal field A (high efficiency-signal field A, HE-SIG A), high efficiency signaling field B (high efficiency-signal field B, HE -SIG B), high efficient-short training field (HE-STF), high efficient-long training field (HE-LTF), data, and data packet expansion (packet) extension, PE).
  • legacy short training field legacy-short training field
  • L-STF traditional long training field
  • L-LTF traditional signaling field
  • L-SIG legacy-signal field
  • RL-SIG Repeating traditional signaling field
  • high efficiency-signal field A high efficiency-signal field A, HE-SIG A
  • high efficiency signaling field B high efficiency
  • L-STF is used for automatic gain control, sequence synchronization and coarse frequency offset estimation.
  • the BSS to which the PPDU monitored by the station belongs is the same BSS as the BSS associated with the station, or the receiver/sender of the PPDU monitored by the station belongs to the same BSS as the station , Then the PPDU is intra-BSS PPDU.
  • the PPDU is an intra-BSS PPDU.
  • the BSS to which the PPDU monitored by the station belongs is not the same BSS as the BSS associated with the station, or the receiving/sending end of the PPDU monitored by the station does not belong to the same station.
  • the PPDU is inter-BSS PPDU.
  • the PPDU is an inter-BSS PPDU.
  • the above method for the station to determine whether the PPDU is an intra-BSS PPDU or an inter-BSS PPDU is only an example, and the detailed description can refer to the prior art.
  • the ML entity has the ability to transmit and receive on multiple frequency bands.
  • the foregoing multiple frequency bands include but are not limited to: 2.4 GHz frequency band, 5 GHz frequency band, and 6 GHz frequency band.
  • the spatial path through which the ML entity performs data transmission on a frequency band can be called a link. In other words, the ML entity supports multi-link communication.
  • each link supported by the ML entity corresponds to a frequency band.
  • the ML entity may also be called ML STA entity.
  • the ML entity includes multiple STAs. Each STA in the ML entity can establish a link for communication.
  • the ML entity A includes site A1-site AN
  • the ML entity B includes site B1-site BN.
  • the station A1 and the station B1 communicate through the link 1, and the communication link 2 between the station A2 and the station B2 communicates, and so on, the station AN and the station BN communicate through the link N.
  • multiple STAs in the ML entity may have the same MAC address or may have different MAC addresses. Multiple STAs in the ML entity may be located at the same physical location or at different physical locations.
  • the ML entity can be called an ML AP entity. If the STA in the ML entity is a non-AP STA, the ML entity may be called an ML non-AP STA entity, or an ML non-AP entity. In the embodiments of the present application, unless otherwise specified, the ML entity may be either an ML AP entity or an ML non-AP entity.
  • the non-AP STA on one link in the ML non-AP entity can be associated with the AP on the same link in the ML AP entity, so that the non-AP STA on one link in the ML non-AP entity can be associated with the ML Communication between APs on the same link in the AP entity.
  • an association relationship may be established between the ML AP entity and the ML non-AP entity to ensure normal communication between the ML AP entity and the ML non-AP entity.
  • association relationship between the ML AP entity and the ML non-AP entity includes: the association relationship between the station of the ML AP entity on a link and the station of the ML non-AP entity on the same link .
  • the embodiment of the present application does not limit the implementation manner of establishing an association relationship between the ML non-AP entity and the ML AP entity.
  • the ML non-AP entity and the ML AP entity establish an association relationship on the link; or, the ML non-AP entity and the ML AP entity establish an ML non-AP entity and ML on the same link.
  • the ML non-AP entity and the ML AP entity establish an association relationship on a link.
  • the SL entity refers to an STA that supports only one link.
  • the SL entity may be a legacy STA, that is, an STA that only supports the existing 802.11 standard and does not support the next-generation 802.11 standard.
  • the following uses an example to illustrate the situation where the ML entity receives and sends out of synchronization on multiple links.
  • the ML AP entity sends PPDU#1 to the ML non-AP entity 1 on the first link. Since the ML non-AP entity 2 does not know that the ML AP entity is sending PPDU#1 on the first link, the ML non-AP entity 2 may send PPDU#2 to the ML AP entity on the second link. In this case, the ML AP entity sending PPDU#1 on the first link will affect the ML AP entity receiving PPDU#2 on the second link, resulting in PPDU#2 transmission failure.
  • the ML non-AP entity 1 sends a PPDU to the ML AP entity on the first link. Since the ML non-AP entity 2 does not know that the ML non-AP entity 1 is sending PPDU#1 on the first link, the ML non-AP entity 2 may send PPDU#2 to the ML AP entity on the second link. The transmission time of PPDU#2 is shorter than the transmission time of PPDU#1. If the ML AP entity sends a BA frame on the second link, it will affect the ML entity to receive PPDU#1 on the first link, resulting in PPDU#1 transmission failure. If the ML AP does not send the BA frame on the second link, the ML non-AP entity 2 will consider that the transmission of PPDU#2 has failed because it has not received the BA frame.
  • the asynchronous reception and transmission of the ML entity on multiple links specifically refers to the fact that the ML entity sends signals on a part of the links while the ML entity receives signals on another part of the links.
  • the embodiments of the present application provide the following technical solutions, the specific content of which can be referred to below.
  • the technical solution of the present application is applied to the WLAN, and the standard adopted by the WLAN may be the IEEE 802.11 standard, such as the 802.11ax standard, and the next-generation 802.11 standard.
  • the applicable scenarios of the technical solution of this application include: communication scenarios between ML entities and ML entities, and communication scenarios between ML entities and SL entities.
  • the communication scenario between the ML entity and the ML entity may be: the communication scenario between the ML non-AP entity and the ML AP entity; or, the communication scenario between the ML non-AP entity and the ML non-AP entity ; Or, the communication scenario between the ML AP entity and the ML AP entity.
  • the communication scenario between the ML entity and the SL entity may be: the communication scenario between the ML non-AP entity and the traditional AP; or, the communication scenario between the ML AP entity and the traditional non-AP STA; or , The communication scenario between the ML AP entity and the traditional AP; or, the communication scenario between the ML non-AP entity and the traditional non-AP STA.
  • a communication protection method provided by an embodiment of this application includes the following steps:
  • the ML entity listens to the first PPDU on the first link.
  • the ML entity can support multiple links.
  • the first link is any one of the multiple links supported by the ML entity.
  • the station of the first link of the ML entity listens to the first PPDU on the first link.
  • the ML entity judges whether the first PPDU is an intra-BSS PPDU or an inter-BSS PPDU.
  • the station of the first link of the ML entity determines whether the first PPDU is an intra-BSS PPDU or an inter-BSS PPDU.
  • the method for determining whether the first PPDU is an intra-BSS PPDU or an inter-BSS PPDU can refer to the prior art, which will not be repeated here.
  • the ML entity will perform the following step S103.
  • the ML entity will perform the following step S105.
  • the ML entity judges whether the value of the duration field of the first PPDU is greater than the current value of the target NAV of the second link.
  • the second link is a link other than the first link among the multiple links supported by the ML entity. That is, the first link and the second link are two different links.
  • the value of the duration field of the first PPDU is used to indicate the time that the sender of the first PPDU occupies the channel on the first link.
  • the target NAV of the second link can be used to record the time when the station is prohibited from actively initiating competition on the second link.
  • the target NAV of the second link may reuse the NAV in the current standard, or may be a newly configured NAV.
  • the target NAV of the second link may adopt one of the following situations:
  • Case 1 The target NAV of the second link reuses the intra-NAV of the second link.
  • the ML non-AP entity includes: intra-NAV and basic NAV.
  • the target NAV of the second link is a newly configured NAV.
  • the ML non-AP entity includes: intra-NAV, basic NAV, and the first NAV.
  • the first NAV is the target NAV, and the first NAV may also be referred to as ML NAV.
  • the target NAV of the second link may adopt one of the following situations:
  • Case 1 The target NAV of the second link reuses the intra-NAV of the second link.
  • the ML AP entity includes: intra-NAV and basic NAV.
  • the target NAV of the second link is a newly configured NAV.
  • the ML AP entity includes: intra-NAV, basic NAV, and the first NAV; or, the ML AP entity includes: the first NAV and the second NAV.
  • the first NAV is the target NAV.
  • the second NAV is the NAV configured by the AP in a scenario where the AP is configured with only one NAV in the current standard.
  • the station on the second link of the ML entity obtains the judgment result of the station on the first link of the ML entity on whether the first PPDU is an intra-BSS PPDU.
  • the station of the second link of the ML entity further obtains the value of the duration field of the first PPDU from the station of the first link of the ML entity. After that, the station of the second link of the ML entity determines whether the value of the duration field of the first PPDU is greater than the current value of the target NAV of the second link.
  • the ML entity performs the following step S104. In the case that the value of the duration field of the PPDU is less than or equal to the current value of the target NAV of the second link, the ML entity executes the following step S105.
  • the ML entity updates the value of the target NAV of the second link to the value of the duration field of the first PPDU. value.
  • the station of the second link of the ML entity updates the value of the target NAV of the second link to the value of the duration field of the first PPDU. For example, if the current value of the target NAV of the second link is 10, and the value of the duration field of the first PPDU is 12, the station of the second link of the ML entity will set the value of the target NAV of the second link Update to 12.
  • the ML entity does not update the value of the target NAV of the second link.
  • the station of the second link of the ML entity does not update the value of the target NAV of the second link.
  • the ML entity listens to the first PPDU sent by other intra-BSS stations on the first link, and the value of the duration field of the first PPDU is greater than that of the second link
  • the value of the target NAV the ML entity updates the value of the target NAV of the second link to the value of the duration field of the first PPDU, so as to ensure the duration of the ML entity in the first PPDU after the first PPDU is transmitted.
  • the PPDU will not be sent within the duration indicated by the field, which will not cause other ML entities in the same BSS to receive PPDUs on one link and send PPDUs on another link at the same time, ensuring other MLs in the same BSS Normal communication of the entity.
  • the ML non-AP entity 1 listens to PPDU#1 on the first link, and PPDU#1 is sent by the ML AP to the ML non-AP entity 2 entity.
  • the station of the first link of the ML non-AP entity 1, the station of the first link of the ML non-AP entity 2, and the station of the first link of the ML AP entity belong to the same BSS.
  • the ML non-AP entity 1 uses the value of the duration field of PPDU#1 to set the target NAV of the second link. Therefore, the ML non-AP entity 1 will not send PPDUs to the ML AP entity on the second link before the value of the target NAV reaches 0.
  • the ML AP entity when the ML AP entity sends PPDU#1 to the ML non-AP entity 2 on the first link, the ML AP entity does not need to receive PPDU#2 on the second link. In this way, the normal communication of the ML AP entity is guaranteed. It should be noted that using the value of the duration field of PPDU#1 to set the target NAV of the second link does not have to be performed after the transmission of PPDU#1 ends. If the value of the duration field can be used during the transmission of PPDU#1 If obtained, the target NAV of the second link can be set immediately after obtaining the value of the duration.
  • the value of the duration can be obtained after the first MPDU is received; for example, if the SIG field of PPDU1 carries the TXOP Duration field, it can be received in the SIG field After the completion, the value of the duration field is obtained through the TXOP Duration field.
  • the communication protection method further includes steps S106-S107.
  • the ML entity listens to the CF-End frame on the first link.
  • the CF-End frame is used to indicate the end of the contention-free period.
  • stations in the same BSS can initiate channel competition to access the channel.
  • the station of the first link of the ML entity listens to the CF-End frame on the first link.
  • the station of the first link of the ML entity After listening to the CF-End frame, the station of the first link of the ML entity will determine whether the CF-End frame is an intra-BSS PPDU. If the CF-End frame is an intra-BSS PPDU, the station in the intra-BSS does not occupy the channel on the first link, so the station on the first link of the ML entity can perform channel access on the first link.
  • the CF-End frame is an intra-BSS PPDU, indicating that the CF-End frame belongs to the BSS associated with the station of the first link of the ML entity.
  • the station of the first link of the ML entity will determine whether the CF-End frame is an intra-BSS PPDU, including: if the BSSID carried in the CF-End frame is associated with the station of the first link of the ML entity If the BSSID of the BSS of the ML entity is the same, the station of the first link of the ML entity can determine that the CF-End frame is an intra-BSS PPDU; otherwise, the station of the first link of the ML entity can determine that the CF-End frame is not an intra- BSS PPDU. It should be understood that there are other implementation methods for determining whether the CF-End frame is an intra-BSS PPDU, and the embodiment of the present application is not limited thereto.
  • the station of the second link of the ML entity sets the value of the target NAV of the second link to 0.
  • the target NAV of the second link of the ML entity is updated according to the value of the duration field of the first PPDU heard on the first link to ensure that the ML entity is not on the second link
  • the data is sent on the first link to avoid affecting the communication of other ML entities in the same BSS on the first link.
  • the ML entity listens to the CF-End frame in the same BSS on the first link, it means that the communication of other ML entities in the same BSS on the first link has ended, so the ML entity can
  • the value of the target NAV is set to 0, so that the virtual carrier monitoring of the ML entity on the second link is not affected by the communication on the first link, avoiding delays in channel competition of the ML entity on the second link, which is beneficial Improve the ML entity's utilization of the second link.
  • the communication protection method further includes step S108.
  • the ML entity If the ML entity does not hear the second PPDU on the first link within the preset time period, and the value of the target NAV of the second link is based on the value of the duration field of the first PPDU If the value is updated, the ML entity resets the target NAV of the second link.
  • the second PPDU and the first PPDU are from the same site.
  • the ML entity determines that it does not hear the second PPDU on the first link within the preset duration. If the ML entity listens to one or more PPDUs on the first link within the preset duration, and if the sending site of the one or more PPDUs is different from the sending site of the first PPDU, the ML entity determines the first PPDU The one or more PPDUs are from a different station, and the ML entity determines that the second PPDU is not heard on the first link within the preset time period.
  • the preset duration (2 ⁇ aSIFSTime)+(transmission duration of the first PPDU response frame)+aRxPHYStartDelay+(2 ⁇ aSlotTime).
  • aSIFSTime represents the duration of SIFS.
  • aSlotTime represents the length of a time slot. aSlotTime is generally 9 microseconds.
  • the first PPDU response frame may be a CTS frame.
  • the transmission duration of the first PPDU response frame is the transmission duration of the CTS frame, which is usually recorded as CTS_Time. It should be noted that the transmission duration of the CTS frame can be determined according to the length of the CTS frame and the data transmission rate of the most recently received RTS frame used to update the NAV.
  • aRxPHYStartDelay represents the duration of the preset delay.
  • the preset delay refers to the delay between the start of receiving the PPDU by the receiving antenna and the publication of the primitive PHY-RXSTART.indication.
  • aRxPHYStartDelay corresponds to different values.
  • aRxPHYStartDelay is 20 microseconds.
  • aRxPHYStartDelay is 28 microseconds.
  • aRxPHYStartDelay is 40 microseconds.
  • the ML entity resets the target NAV of the second link, and can adopt any of the following implementation modes:
  • Manner 2 The ML entity sets the value of the target NAV of the second link to the first value.
  • the end time determined by the first value is the same as the end time determined by the second value.
  • the second value is based on the target NAV according to the first value.
  • the value of the duration field of the PPDU is the value of the target NAV before the update.
  • the ML entity sets the target NAV of the second link The value is updated to L1.
  • the second value of the target NAV is L2
  • the end time determined by the second value is time T1+L2.
  • the ML entity sets the value of the target NAV of the second link to the first value, since the end time of the first value is also at time T1+L2, the first value is L2 -L3.
  • the ML entity does not hear the second PPDU sent by the sender of the first PPDU on the first link within the preset time period, it means that the sender of the first PPDU may not be there.
  • the channel is occupied on the first link, so the ML entity can initiate channel contention on the first link to send the first PPDU on the first link.
  • the target NAV is updated according to the value of the duration field of the first PPDU, the ML entity resets the target NAV so that the virtual carrier monitoring of the ML entity on the second link is not affected.
  • the influence of the communication on the first link avoids delaying the channel competition of the ML entity on the second link, which is beneficial to improve the utilization rate of the ML entity on the second link.
  • a communication protection method provided by an embodiment of this application includes the following steps:
  • the ML entity sends the first PPDU on the first link.
  • the ML entity can support multiple links.
  • the first link may be any one of multiple links supported by the ML entity.
  • the first PPDU includes a duration field.
  • the duration field of the first PPDU is used to indicate the duration of the first period.
  • the first time period is a time period during which the ML entity occupies a channel on the first link.
  • the start time of the first time period is the end time of the transmission of the PPDU.
  • the station of the first link of the ML entity sends the PPDU on the first link.
  • the ML entity sends the MAC frame on the second link.
  • the second link is a link other than the first link among the multiple links supported by the ML entity. That is, the first link and the second link are two different links.
  • the MAC frame is used to indicate the duration of the second period.
  • the intra-BSS station on the second link in the second time period is prohibited from sending the second PPDU, and the second PPDU is different from the first PPDU.
  • the start time of the second time period is the end time of the transmission of the MAC frame.
  • the end time of the second time period is the same as the end time of the first time period.
  • the transmission start time and the transmission end time of the MAC frame are both before the transmission end time of the first PPDU, so as to ensure that the intra-BSS station on the second link can receive the transmission before the PPDU transmission is completed.
  • This MAC frame so that the intra-BSS station on the second link will not send the second PPDU in the first time period.
  • the station on the second link of the ML entity learns that the station on the first link of the ML entity sends the first PPDU on the first link
  • the station on the second link of the ML entity is on the second link.
  • MAC frames are sent on the link.
  • the MAC frame may be an announcement frame or a QTP frame. It should be noted that the announcement frame is a new type of control frame defined in the embodiment of this application.
  • the announcement frame can be implemented in the following two ways:
  • the announcement frame includes a duration field and a duration field.
  • the duration field of the announcement frame is used to set the value of NAV maintained by the intra-BSS station on the second link.
  • the duration field of the announcement frame is not used to set the NAV value maintained by the OBSS station on the second link.
  • the intra-BSS station on the second link reads the duration field included in the announcement frame, and uses the value of the duration field included in the announcement frame to set the value of the NAV maintained by itself.
  • the OBSS station on the second link will not use the value of the duration field of the announcement frame to set the value of NAV maintained by itself.
  • the site uses the value of the duration field included in the announcement frame to set the value of the NAV maintained by itself. Specifically, when the value of the duration field included in the announcement frame is greater than the value of the NAV maintained by the site itself , The site will update the NAV value to the value of the duration field. Otherwise, the site does not update the NAV value.
  • the intra-BSS site on the above second link refers to a site that belongs to the same BSS as the site on the second link of the ML entity.
  • the OBSS site on the second link refers to a site that does not belong to the same BSS as the site on the second link of the ML entity.
  • the value of the duration field of the announcement frame is equal to the duration of the second period, so that intra-BSS stations on the second link cannot perform channel access at least during the second period to avoid The intra-BSS site on the second link causes interference to the communication of the ML entity.
  • FIG. 11 is a schematic diagram of an announcement frame provided by an embodiment of the application.
  • the announcement frame includes at least the following fields: frame control (frame control), duration (duration), receiving address (RA), transmitting address (TA), ML transmission time (ML trans time), frame check Sequence (frame check sequence, FCS).
  • the ML transmission duration field in the announcement frame shown in FIG. 11 is the duration field of the announcement frame mentioned above. That is, the ML transmission duration field in the announcement frame shown in FIG. 11 is used to set the value of NAV maintained by the intra-BSS station on the second link.
  • the frame control field also includes the following fields: protocol version (protocol version), type (type), and subtype (subtype).
  • control frame is the announcement frame provided in this embodiment of the application.
  • Table 1 shows the meaning of the type field and the subtype field under different values. As shown in Table 1, if the value of the type field of a control frame is 01 and the value of the subtype field is 0001, the control frame is an announcement frame.
  • FIG. 12 is a schematic diagram of an announcement frame provided by an embodiment of the application.
  • the announcement frame is a frame containing a new type of high throughput (HT) control field defined in this application.
  • the announcement frame includes one of the following fields: frame control, duration/identification, address 1, address 2, address 3, sequence control, address 4, quality of service (quality of service) service, QoS) control, HT control, frame body, and FCS.
  • duration/identification field of the announcement frame shown in FIG. 12 is equivalent to the duration field of the announcement frame mentioned above.
  • the HT control field includes one of the following fields: control ID and control information (control information).
  • the value of the control ID field is a preset value to indicate that the HT control frame is an announcement frame.
  • the control information field in the announcement frame shown in FIG. 12 is equivalent to the duration field of the announcement frame mentioned above. That is, the control information field in the announcement frame shown in FIG. 12 is used to indicate the duration of the second period.
  • the control information field may be 16 bits.
  • FIG. 13 is a schematic diagram of an announcement frame provided by an embodiment of the application.
  • the announcement frame is a frame containing a new type of extremely high throughput (EHT) control field defined in this application.
  • EHT extremely high throughput
  • the announcement frame includes one of the following fields: frame control, duration/identification, address 1, address 2, address 3, sequence control, address 4, service quality control, EHT control, frame body, and FCS .
  • duration/identification field in the announcement frame shown in FIG. 13 is equivalent to the duration field of the announcement frame mentioned above.
  • the EHT control field includes one of the following fields: control ID and control information (control information).
  • the value of the control ID field is a preset value to indicate that the EHT control frame is an announcement frame.
  • the preset value may be 7.
  • the control information field in the announcement frame shown in FIG. 13 is equivalent to the duration field in the announcement frame mentioned above. That is, the control information field in the announcement frame shown in FIG. 13 is used to indicate the duration of the second period.
  • the control information field may be 16 bits.
  • the announcement frame includes a duration field.
  • the duration field is used to enable the intra-BSS station on the second link to set NAV. That is, the intra-BSS station on the second link reads the duration field included in the announcement frame, and uses the value of the duration field included in the announcement frame to set the NAV maintained by itself. However, the OBSS station on the second link will not set the NAV maintained by itself with the value of the duration field included in the announcement frame.
  • the value of the duration field included in the announcement frame is equal to the time length of the second time period, so as to ensure normal communication of the ML entity.
  • the ML entity when the ML entity sends a PPDU on the first link, the ML entity sends a MAC frame on the second link, so that other stations in the same BSS on the second link are in the first link. No PPDU will be sent before the end of the period. In this way, it is guaranteed that the ML entity will not send PPDUs on the first link and receive PPDUs on the second link, thereby ensuring normal communication of the ML entity.
  • the ML AP entity sends PPDUs to the ML non-AP entity 1 on the first link, and at the same time, the ML AP entity sends MAC frames on the second link, so that the same
  • the non-AP STA in the BSS will not send PPDUs to the ML AP. Therefore, the ML AP entity will not send PPDUs on the first link and receive PPDUs on the second link, ensuring normal communication of the ML AP entity.
  • a communication protection method provided by an embodiment of this application includes the following steps:
  • the ML entity listens to the start of the PPDU on the first link.
  • the ML entity can support multiple links.
  • the first link may be any one of the multiple links supported by the ML entity.
  • the start of the PPDU may refer to the L-STF of the PPDU.
  • L-STF is used to enable stations to receive PPDUs synchronously.
  • the station of the first link of the ML entity listens to the start of the PPDU on the first link.
  • the ML entity suspends counting of the first backoff counter on the second link.
  • the second link is a link other than the first link among the multiple links supported by the ML entity. That is, the first link and the second link are two different links.
  • the station on the second link of the ML entity learns that the station on the first link of the ML entity hears the start of the PPDU, the station on the second link of the ML entity suspends the counting of the first backoff counter . Therefore, the backoff procedure of the ML entity on the second link is suspended.
  • the ML entity judges whether the PPDU is an intra-BSS PPDU or an inter-BSS PPDU.
  • the station of the first link of the ML entity determines whether the PPDU is an intra-BSS PPDU or an inter-BSS PPDU.
  • the method for determining whether the PPDU is an intra-BSS PPDU or an inter-BSS PPDU can refer to the prior art, which will not be repeated here.
  • the ML entity executes the following step S304.
  • the ML entity executes the following step S305.
  • the ML entity continues to fall back on the second link after the transmission of the PPDU is completed.
  • the station of the second link of the ML entity resumes the counting function of the first backoff counter. Therefore, the station of the second link of the ML entity can continue to perform the backoff procedure.
  • the ML entity continues to fall back after the PPDU transmission is completed, including one of the following situations:
  • Case 1 The ML entity continues to roll back after the first moment.
  • the first moment is the end moment of the PPDU transmission.
  • the ML entity waits for the idle time of the second link to reach the second inter-frame interval. After the idle time of the second link reaches the second inter-frame interval, whenever the second link is idle in a time slot, the count value of the first backoff counter of the second link is reduced by 1 until the second link The count value of the first backoff counter of the link is 0.
  • ML entity 1 sends PPDU#1 on the first link.
  • the ML entity 2 detects the start of the PPDU#1 on the first link, the ML entity 2 suspends the counting of the first backoff counter on the second link. At this time, the count value of the first backoff counter is 5 .
  • the ML entity 2 listens to the physical header of PPDU#1 on the second link, based on the information in the physical header, the ML entity 2 determines that the PPDU#1 is an intra-BSS PPDU. Therefore, at the moment when the transmission of PPDU#1 ends, the ML entity 2 resumes the counting function of the first backoff counter on the second link and continues to backoff.
  • the ML entity 2 waits for the idle time of the second link to reach the second inter-frame interval. After the idle time of the second link reaches the second inter-frame interval, the first backoff counter of the second link starts to roll back from 5. When the count value of the backoff counter is reduced to 0, the ML entity 2 sends PPDU#2 on the second link.
  • Case 2 The ML entity continues to roll back after the second moment.
  • the second moment is the end moment of transmission of the response frame corresponding to the PPDU.
  • the ML entity waits for the idle time of the second link to reach the second inter-frame interval. After the idle time of the second link reaches the second inter-frame interval, whenever the second link is idle in a time slot, the count value of the first backoff counter of the second link is reduced by 1 until the second link The count value of the first backoff counter of the link is 0.
  • the second moment may be determined according to the PPDU transmission end moment, the first inter-frame interval, and the maximum transmission duration of the BA frame.
  • the first inter-frame interval may be SIFS, and the embodiment of the present application is not limited thereto.
  • ML entity 1 sends PPDU#1 on the first link.
  • the ML entity 2 detects the start of the PPDU#1 on the first link, the ML entity 2 suspends the counting of the first backoff counter on the second link. At this time, the count value of the first backoff counter is 5 .
  • the ML entity 2 listens to the physical header of PPDU#1 on the second link, based on the information in the physical header, the ML entity 2 determines that the PPDU#1 is an intra-BSS PPDU.
  • the ML entity 2 determines the second time according to the transmission end time of PPDU#1, the first inter-frame interval, and the maximum transmission duration of the response frame.
  • the ML entity 2 resumes the counting function of the first backoff counter on the second link and continues to backoff. Specifically, the ML entity 2 waits for the idle time of the second link to reach the second inter-frame interval. After the idle time of the second link reaches the second inter-frame interval, the first backoff counter of the second link starts to roll back from 5. When the count value of the first backoff counter is reduced to 0, the ML entity 2 sends PPDU#2 on the second link.
  • Case 3 The ML entity continues to roll back after the third moment.
  • the third moment is the end moment determined by the duration field of the PPDU. Specifically, the time interval between the third moment and the end moment of the PPDU transmission is equal to the value of the duration field of the PPDU.
  • the ML entity waits for the idle time of the second link to reach the second inter-frame interval. After the idle time of the second link reaches the second inter-frame interval, whenever the second link is idle in a time slot, the count value of the first backoff counter of the second link is reduced by 1 until the second link The count value of the first backoff counter of the link is 0.
  • ML entity 1 sends PPDU#1 on the first link.
  • the ML entity 2 detects the start of the PPDU#1 on the first link, the ML entity 2 suspends the counting of the first backoff counter on the second link. At this time, the count value of the first backoff counter is 5 .
  • the ML entity 2 listens to the physical header of PPDU#1 on the second link, based on the information in the physical header, the ML entity 2 determines that the PPDU#1 is an intra-BSS PPDU.
  • the ML entity 2 determines the third time according to the transmission end time of PPDU#1 and the value of the duration field of PPDU#1.
  • the ML entity 2 resumes the counting function of the first backoff counter on the second link and continues to back off. Specifically, the ML entity 2 waits for the idle time of the second link to reach the second inter-frame interval. After the idle time of the second link reaches the second inter-frame interval, the first backoff counter of the second link starts to roll back from 5. When the count value of the first backoff counter is reduced to 0, the ML entity 2 sends PPDU#2 on the second link.
  • the ML entity continues to fall back on the second link.
  • the station of the second link of the ML entity resumes the counting function of the first backoff counter. Therefore, the station of the second link of the ML entity can continue to perform the backoff procedure.
  • the count value of the first backoff counter of the second link is decreased by 1, until the first backoff of the second link The count value of the counter is 0.
  • the ML entity waits for the idle time of the second link to reach the second inter-frame interval. After the idle time of the second link reaches the second inter-frame interval, whenever the second link is idle in a time slot, the count value of the first backoff counter of the second link is reduced by 1 until the second link The count value of the first backoff counter of the link is 0.
  • the foregoing fourth moment is the moment when the ML entity determines that the PPDU is an inter-BSS PPDU.
  • the ML entity 1 sends PPDU#1 on the first link.
  • the ML entity 2 detects the start of the PPDU#1 on the first link, the ML entity 2 suspends the counting of the first backoff counter on the second link. At this time, the count value of the first backoff counter is 5 .
  • the ML entity 2 determines that the PPDU#1 is an inter-BSS PPDU. In this case, the ML entity 2 immediately resumes the counting function of the first backoff counter on the second link, and continues to back off. After the backoff ends, the ML entity 2 sends PPDU#2 on the second link.
  • the ML entity suspends the counting of the first backoff counter on the second link.
  • the ML entity does not continue to roll back until the PPDU is transmitted. Therefore, during the PPDU transmission process on the first link, the ML entity will not send PPDUs on the second link, so as to avoid causing other ML entities in the same BSS to receive signals on the first link and receive signals on the other link. The condition of sending signals on the link.
  • the ML entity determines that the PPDU is an inter-BSS PPDU, the ML entity immediately continues to roll back, thereby ensuring that the ML entity can normally perform channel access on the second link.
  • the communication protection method further includes steps S306-S307 after step S302. And, step S305 can be replaced with steps S305a-S305b.
  • the ML entity configures a second backoff counter on the second link.
  • the station of the second link of the ML entity is configured with a second backoff counter, and the initial value of the second backoff counter is the current value of the first backoff counter.
  • the current value of the first backoff counter is 15, and the initial value of the second backoff counter is also 15.
  • the ML entity performs a virtual back-off based on the second back-off counter.
  • the virtual backoff means that if the second link is in the idle state at the current moment, whenever the second link is in the idle state in a time slot, the ML entity sets the second backoff counter The count value is reduced by 1. If the second link is busy at the current moment, the ML entity waits for the idle time of the second link to reach the second inter-frame interval; when the idle time of the second link reaches the second frame After the interval, whenever the second link is in an idle state in a time slot, the ML entity decrements the count value of the second backoff counter by one.
  • the foregoing second inter-frame interval may be AIFS or other inter-frame intervals, and the embodiment of the present application is not limited thereto.
  • the ML entity needs to wait for the idle time of the second link to reach the second inter-frame interval. After the idle time of the second link reaches the second inter-frame interval, the ML entity recounts the second backoff counter.
  • the busy/idle status of the second link may be determined according to the busy/idle status of the main channel of the second link. That is, if the main channel of the second link is busy, it means that the second link is busy. If the main channel of the second link is in an idle state, it means that the second link is in an idle state.
  • the main channel of the second link may be pre-configured or defined in the standard, and the embodiment of the present application is not limited thereto.
  • the main channel of the second link may be the 20 MHz channel with the highest frequency in the frequency band corresponding to the second link.
  • the main channel of the second link may be a 20 MHz channel with the lowest frequency in the frequency band corresponding to the second link.
  • the ML entity before the ML entity determines whether the PPDU is an intra-BSS PPDU or an inter-BSS PPDU, if the count value of the second backoff counter is decremented to 0, the ML entity can use any of the following methods to maintain The second backoff counter.
  • the station of the second link of the ML entity keeps the count value of the second backoff counter to 0.
  • Manner 2 The ML entity resets the count value of the second backoff counter. It should be understood that after the second backoff counter is reconfigured with the count value, the ML entity continues to backoff based on the second backoff counter.
  • the ML entity resetting the count value of the second backoff counter includes: the ML entity resets the count value of the second backoff counter according to the doubled contention window. Or, the ML entity resets the count value of the second backoff counter according to the minimum value of the contention window. Or, the ML entity resets the count value of the second backoff counter according to the contention window.
  • the above doubling specifically means that if the contention window CW does not reach CWmax, the CW is updated to 2*CW+1; if the contention window CW is CWmax, the CW is kept unchanged.
  • steps S306-S307 and step S303 are executed simultaneously.
  • the station of the second link of the ML entity sets the count value of the first backoff counter to the count value of the second backoff counter.
  • the current value of the first backoff counter is 15.
  • the ML entity determines that the PPDU is an inter-BSS PPDU if the count value of the second backoff counter is 10, the count value of the first backoff counter is updated to 10.
  • the ML entity continues to back off on the second link based on the first backoff counter.
  • the station on the second link of the ML entity restores the counting function of the first backoff counter on the second link, and continues to backoff.
  • the count value of the first backoff counter of the second link is decreased by 1, until the first backoff of the second link The count value of the counter is 0.
  • the foregoing fourth moment is the moment when the ML entity determines that the PPDU is an inter-BSS PPDU.
  • the count value of the first backoff counter of the second link is decreased by 1 until the count value of the first backoff counter of the second link is 0.
  • the ML entity 1 sends PPDU#1 on the first link.
  • the ML entity 2 detects the start of the PPDU#1 on the first link, the ML entity 2 suspends the counting of the first backoff counter on the second link. At this time, the count value of the first backoff counter is 5 .
  • the ML entity 2 configures a second backoff counter on the second link, and the count value of the second backoff counter is 5.
  • the second link In the two time slots where the ML entity 2 listens to the physical packet header of PPDU#1 on the first link, the second link is in an idle state, so the count value of the second backoff counter is reduced to 3.
  • the ML entity 2 determines that the PPDU #1 is an inter-BSS PPDU. In this case, the ML entity 2 updates the count value of the first backoff counter to 3, and continues to backoff. After the count value of the first backoff counter is reduced to 0, the ML entity 2 sends PPDU#2 on the second link.
  • ML entity 1 sends PPDU#1 on the first link.
  • the ML entity 2 detects the start of the PPDU#1 on the first link, the ML entity 2 suspends the counting of the first backoff counter on the second link. At this time, the count value of the first backoff counter is 5 .
  • the ML entity 2 configures a second backoff counter on the second link, and the count value of the second backoff counter is 5. In the two time slots where the ML entity 2 listens to the physical packet header of PPDU#1 on the first link, the second link is in an idle state, so the count value of the second backoff counter is reduced to 3.
  • the ML entity 2 After the ML entity 2 listens to the physical header of PPDU #1 on the second link, the ML entity 2 determines that the PPDU #1 is an intra-BSS PPDU. In this case, the ML entity 2 does not update the count value of the first backoff counter, so the ML entity 2 continues to backoff based on the first backoff counter with a count value of 5. After the count value of the first backoff counter is reduced to 0, the ML entity 2 sends PPDU#2 on the second link.
  • the ML entity suspends the counting of the first backoff counter on the second link.
  • the ML entity configures a second backoff counter, and the initial value of the second backoff counter is the current value of the first backoff counter. Therefore, the ML entity performs a virtual back-off based on the second back-off counter.
  • the ML entity determines that the PPDU is an inter-PPDU, the ML entity then sets the count value of the first backoff counter with the count value of the second backoff counter, so that the first backoff counter is not affected by the previous suspension.
  • the PPDU is an inter-BSS PPDU
  • the backoff process of the ML entity on the second link is not affected, thereby avoiding the ML entity being at a disadvantage in channel competition and ensuring that the ML entity is Use of roads.
  • the communication protection method further includes steps S308-S309 after step S302. And, step S305 can be replaced with steps S305c-S305d.
  • the ML entity sets a third counter on the second link.
  • the third counter is used to record the idle time of the second link.
  • the initial value of the third counter can be zero.
  • the ML entity updates the count value of the third counter according to the idle time of the second link.
  • the ML entity adds 1 to the count value of the third counter.
  • the ML entity sets the count value of the first backoff counter according to the count value of the third counter.
  • the count value of the first backoff counter is equal to the current value of the first backoff counter minus the count value of the third counter. If the current value of the first back-off counter minus the count value of the third counter is less than 0, the count value of the first back-off counter is 0.
  • the ML entity may set the count value of the first backoff counter to 1.
  • the current value of the first backoff counter is 10. If the ML entity determines whether the PPDU is an inter-BSS PPDU, and the idle time of the second link reaches 12 time slots, the count value of the third counter is 12. In this way, when determining that the PPDU is an inter-BSS PPDU, the ML entity may set the count value of the first backoff counter to 0.
  • the ML entity continues to back off on the second link based on the first backoff counter.
  • the station on the second link of the ML entity restores the counting function of the first backoff counter on the second link, and continues to backoff.
  • the count value of the first backoff counter of the second link is decreased by 1, until the first backoff of the second link The count value of the counter is 0.
  • the foregoing fourth moment is the moment when the ML entity determines that the PPDU is an inter-BSS PPDU.
  • the count value of the first backoff counter of the second link is decreased by 1 until the count value of the first backoff counter of the second link is 0.
  • FIG. 18 The technical solution shown in FIG. 18 is exemplified in conjunction with FIG. 16(g).
  • ML entity 1 sends PPDU#1 on the first link.
  • the ML entity 2 detects the start of the PPDU#1 on the first link, the ML entity 2 suspends the counting of the first backoff counter on the second link. At this time, the count value of the first backoff counter is 5 .
  • the ML entity 2 configures a third counter on the second link. In the two time slots where the ML entity 2 listens to the physical packet header of PPDU#1 on the first link, the second link is in an idle state, so the count value of the third counter is updated to 2.
  • the ML entity 2 After the ML entity 2 listens to the physical packet header of the PPDU #1 on the second link, the ML entity 2 determines that the PPDU #1 is an inter-BSS PPDU. In this case, the ML entity 2 updates the count value of the first backoff counter to 3 according to the count value of the third backoff counter. The ML entity 2 continues to back off based on the first backoff counter with a count value of 3. After the count value of the first backoff counter is reduced to 0, the ML entity 2 sends PPDU#2 on the second link.
  • the ML entity After the ML entity listens to the start of the PPDU on the first link, the ML entity suspends the counting of the first backoff counter on the second link. At the same time, the ML entity configures a third counter, and uses the third counter to record the idle time of the second link.
  • the ML entity determines that the PPDU is an inter-PPDU, the ML entity updates the count value of the first backoff counter according to the counter of the third counter, so that the first backoff counter is not affected by the previous suspension.
  • the PPDU is an inter-BSS PPDU
  • the backoff process of the ML entity on the second link is not affected, thereby avoiding the ML entity being at a disadvantage in channel competition and ensuring that the ML entity is Use of roads.
  • a communication protection method provided in an embodiment of this application includes the following steps:
  • the ML non-AP entity listens to the first PPDU on the first link.
  • ML non-AP supports multiple links.
  • the first link is any one of multiple links supported by the ML non-AP entity.
  • the first PPDU may be a single user (single user, SU) PPDU, an extended range (extended range, ER) SU PPDU, a trigger frame-based (TB) PPDU, or an uplink multi-user (multiple user, MU) Any of PPDUs.
  • SU single user
  • ER extended range
  • TB trigger frame-based
  • MU uplink multi-user
  • the station on the first link of the ML non-AP entity listens to the first PPDU on the first link.
  • the ML non-AP station After listening to the first PPDU, the ML non-AP station determines whether the receiver of the first PPDU is the ML AP entity associated with the ML non-AP entity. For example, if the BBS color in the SIG field of the first PPDU is the same as the BSS color of the BSS to which the station of the first link of the ML non-BSS entity belongs, and the UL/DL parameter in the SIG field of the first PPDU is used When it is indicated that the first PPDU is for uplink transmission, the receiving end of the first PPDU is the ML AP entity associated with the ML non-AP entity.
  • the second link is a link other than the first link among the multiple links supported by the ML non-AP.
  • the end time of the second PPDU is the same as the end time of the first PPDU to ensure that the ML AP entity associated with the ML non-AP entity can receive PPDUs on the first link and the second link at the same time , And send BA frames at the same time.
  • the ML non-AP entity can determine the transmission duration of the second PPDU according to the transmission duration of the first PPDU. Specifically, the ML non-AP entity determines the transmission duration of the second PPDU according to the start time of the first PPDU, the transmission duration of the first PPDU, and the start time of the second PPDU.
  • the starting time of the first PPDU is the time when the ML non-AP entity listens to the L-STF of the first PPDU on the first link.
  • the start moment of the second PPDU is determined by the ML non-AP entity itself.
  • the transmission duration of the first PPDU may be determined according to the L-SIG field of the first PPDU.
  • the L-SIG field of the first PPDU includes a RATE field and a LENGTH field.
  • the RATE field is used to indicate the transmission rate of the first PPDU.
  • the LENGTH field is used to indicate the data length of the first PPDU. Based on the RATE field and the LENGTH field, it can be calculated that the end time of the L-SIG field is the length of time from the end time of the first PPDU. The specific calculation method can refer to the prior art.
  • the transmission duration of the first PPDU includes: the duration between the start time of the first PPDU and the end time of the L-SIG field of the first PPDU, and the end time of the L-SIG field can reach the end of the first PPDU The length of time between moments.
  • the ML non-AP entity can determine the start time of the second PPDU and the RATE field in the second PPDU according to the transmission duration of the second PPDU. And the value of the LENGTH field.
  • the station of the second link of the ML non-AP entity learns from the station of the first link that the receiving end of the first PPDU is the ML AP entity associated with the ML non-AP entity; After that, the station on the second link of the ML non-AP entity sends a second PPDU on the second link.
  • the ML non-AP entity sends the second PPDU on the second link, which also includes: the M1 non-AP entity executes the backoff procedure on the second link; after the backoff procedure ends, the ML non-AP entity The second PPDU is sent on the second link.
  • the foregoing back-off process can refer to the prior art, which will not be repeated here.
  • the ML non-AP entity 1 sends an RTS frame on the first link after the backoff process ends to establish a TXOP. After that, the ML non-AP entity 1 sends PPDU#1 to the ML AP entity on the first link. ML non-AP entity 2 hears PPDU#1. After the ML non-AP entity 2 determines that the PPDU #1 is sent to the ML AP entity associated with the ML non-AP entity 2, the ML non-AP entity 2 sends PPDU #2 on the second link. The end time of PPDU#2 is the same as the end time of PPDU#1. Therefore, the ML AP entity can send the BA frame of PPDU#1 on the first link and the BA frame of PPDU#2 on the second link at the same time.
  • the ML non-AP entity listens to the first PPDU on the first link, and the first PPDU is sent to the ML AP entity associated with the ML non-AP entity, the ML The non-AP entity sends the second PPDU on the second link. Since the end time of the second PPDU is the same as the end time of the first PPDU, the ML AP entity can send the BA frame of the second PPDU and the BA frame of the first PPDU at the same time. In this way, on the one hand, the situation where the ML AP entity sends signals on one link and receives signals on another link is avoided. On the other hand, the ML non-AP entity sends the second PPDU on the second link, which helps to improve the utilization of the second link.
  • the ML entity includes hardware structures and/or software modules corresponding to each function.
  • the present application can be implemented in the form of hardware or a combination of hardware and computer software. Whether a certain function is executed by hardware or computer software-driven hardware depends on the specific application and design constraint conditions of the technical solution. Professionals and technicians can use different methods for each specific application to implement the described functions, but such implementation should not be considered beyond the scope of this application.
  • each functional module may be divided corresponding to each function, or two or more functions may be integrated into one processing module.
  • the above-mentioned integrated modules can be implemented in the form of hardware or software functional modules. It should be noted that the division of modules in the embodiments of the present application is illustrative, and is only a logical function division, and there may be other division methods in actual implementation. The following is an example of dividing each function module corresponding to each function:
  • FIG. 21 is a schematic structural diagram of an ML entity provided by an embodiment of this application. As shown in FIG. 21, the ML entity includes a first unit 101 and a second unit 102.
  • the first unit 101 is configured to listen to the first PPDU on the first link.
  • the second unit 102 is configured to: if the first PPDU is an intra-BSS PPDU, and the value of the duration field of the first PPDU is greater than the value of the target NAV of the second link, then the value of the target NAV of the second link Update to the value of the duration field of the first PPDU, and the second link is any one of the multiple links supported by the ML entity except the first link.
  • the second unit 102 is used for not updating the target NAV value of the second link if the first PPDU is an inter-BSS PPDU; or, if the first PPDU is an intra-BSS PPDU, and If the value of the duration field of the first PPDU is less than or equal to the value of the target NAV of the second link, the value of the target NAV of the second link is not updated.
  • the first unit 101 is also used to listen to the CF-end frame on the first link.
  • the second unit 102 is used for setting the second link when the CF-end frame is an intra-BSS PPDU and the target NAV value of the second link is updated according to the value of the duration field of the first PPDU The value of the target NAV of the road is set to 0.
  • the second unit 102 is used for the first unit 101 on the first link without hearing the second PPDU within a preset period of time, and the value of the target NAV of the second link is based on When the value of the duration field of the first PPDU is updated, the target NAV of the second link is reset, and the second PPDU and the first PPDU are from the same station.
  • the second unit 102 is specifically used to set the target NAV value of the second link to 0; or, to set the target NAV value of the second link to the first value, which is determined by the first value
  • the end time of is the same as the end time determined by the second value, which is the value of the target NAV before the target NAV is updated according to the value of the duration field of the first PPDU.
  • the preset duration (2 ⁇ aSIFSTime)+(the transmission duration of the first PPDU response frame)+aRxPHYStartDelay+(2 ⁇ aSlotTime).
  • aSIFSTime represents the duration of SIFS
  • aRxPHYStartDelay represents the duration of the preset delay
  • aSlotTime represents the duration of a time slot.
  • the RTS frame is carried in the first PPDU, and the response frame is a CTS frame.
  • the target NAV includes one of the following situations: (1) If the ML non-AP entity is configured with intra-BSS NAV and basic basic on the second link NAV, the target NAV is intra-BSS NAV; (2) If the ML non-AP entity is configured with intra-BSS NAV, basic NAV, and the first NAV on the second link, the target NAV is the first NAV.
  • the target NAV includes one of the following situations: (1) If the ML AP entity is configured with intra-BSS NAV and basic NAV on the second link, the target NAV It is intra-BSS NAV; (2) If the ML AP entity is only configured with intra-BSS NAV, basic NAV and the first NAV on the second link, the target NAV is the first NAV; (3) If the ML AP entity is in The first NAV and the second NAV are configured on the second link, and the target NAV is the first NAV.
  • the first unit 101 is configured to send a first PPDU on a first link, the first PPDU includes a duration field, and the duration field included in the first PPDU is used to indicate the duration of the first period.
  • the second unit 102 is used to send a MAC frame on the second link.
  • the MAC frame is used to indicate the duration of the second period.
  • the end time of the first period is the same as the end time of the second period.
  • the second link in the second period The intra-BSS station on the road is prohibited from sending the second PPDU, and the second link is any one of the multiple links supported by the ML entity except the first link.
  • the MAC frame is an announcement frame or a QTP frame.
  • the value of the duration field of the announcement frame is equal to the duration of the second period, and the duration field of the announcement frame is used to set the value of NAV maintained by the intra-BSS site, and the duration field of the announcement frame It is not used to set the NAV value maintained by the OBSS site.
  • the announcement frame includes a duration field and a duration field.
  • the duration field is used to set the value of the NAV maintained by the intra-BSS site.
  • the value of the duration field is 0, and the value of the duration field is equal to the first The duration of the second period.
  • the first unit 101 is used to listen to the start of the PPDU on the first link.
  • the second unit 102 is configured to stop counting of the first backoff counter on the second link, and the second link is any one of the multiple links supported by the ML entity except the first link.
  • the first unit 101 is also used to determine whether the PPDU is an intra-BSS PPDU or an inter-BSS PPDU.
  • the second unit 102 is also used to continue to fall back on the second link when the PPDU is an intra-BSS PPDU, after the PPDU transmission is completed; when the PPDU is an inter-BSS PPDU, in the second link Continue to retreat on the road.
  • the second unit 102 is specifically configured to continue to fall back on the second link after the first time, and the first time is the PPDU transmission end time; or, after the second time, Continue to fall back on the second link, and the second moment is the end time of the transmission of the response frame corresponding to the PPDU; or, after the third moment, continue to fall back on the second link, and the third moment is the duration field of the PPDU The determined end time.
  • the second unit 102 is further configured to configure a second backoff counter on the second link, and the initial value of the second backoff counter is the current value of the first backoff counter; if the second link is currently If the second link is in the idle state at the moment, every time the second link is in the idle state in a time slot, the count value of the second backoff counter is reduced by 1; if the second link is busy at the current moment, wait for the second link The idle time of the road reaches the second inter-frame interval; after the idle time of the second link reaches the second inter-frame interval, whenever the second link is idle in a time slot, the second backoff counter is counted The value is reduced by 1.
  • the second unit 102 is further configured to keep the count value of the second backoff counter at 0 after the count value of the second backoff counter is reduced to zero.
  • the second unit 102 is further configured to reset the count value of the second backoff counter when the count value of the second backoff counter decreases to 0.
  • the second unit 102 is further configured to reset the count value of the second backoff counter according to the doubled contention window; or, the ML entity resets the count value of the second backoff counter according to the contention window; Or, the ML entity resets the count value of the second backoff counter according to the minimum value of the contention window.
  • the second unit 102 is specifically configured to update the count value of the first backoff counter with the count value of the second backoff counter when the PPDU is an inter-BSS PPDU, and based on the first backoff counter, Continue to fall back on the second link.
  • the first unit 101 is configured to listen to the first PPDU on the first link.
  • the second unit 102 is configured to send a second PPDU on the second link when the receiving end of the first PPDU is the ML AP entity associated with the ML entity, and the second link is supported by the ML non-AP entity For any one of the multiple links except the first link, the end time of the first PPDU is the same as the end time of the second PPDU.
  • the second unit 102 is specifically configured to perform the backoff procedure on the second link; after the backoff procedure on the second link ends, the ML non-AP entity sends the second link on the second link Two PPDU.
  • the ML entity provided by the above embodiments of the present application can be implemented in a variety of product forms.
  • the ML entity can be configured as a general processing system; for another example, the ML entity can be implemented by a general bus architecture;
  • the ML entity may be implemented by an application specific integrated circuit (ASIC).
  • ASIC application specific integrated circuit
  • Fig. 22 is a result diagram of possible product forms of the ML entity described in an embodiment of the present application.
  • the ML entity described in the embodiment of the present application may be a communication device, and the communication device includes a processor 201 and a transceiver 202.
  • the communication device further includes a storage medium 203.
  • the processor 201 is configured to execute steps S102, S103, S104, and S105 in FIG. 6, step S107 in FIG. 8, step S108 in FIG. 9, steps S302-S305 in FIG. 15, and step S306 in FIG. , S307, S305a, and S305b, steps S308, S309, S305c, and S305d in FIG. 18.
  • the transceiver 202 is used to perform step S101 in FIG. 6, step S106 in FIG. 8, steps S201 and S202 in FIG. 10, step S301 in FIG. 15, and steps S401 and S402 in FIG.
  • the ML entity described in the embodiment of the present application may also be implemented by a general-purpose processor or a special-purpose processor, that is, commonly known as a chip.
  • the chip includes: a processing circuit 201 and a transceiver pin 202.
  • the chip may also include a storage medium 203.
  • the processing circuit 201 is used to execute steps S102, S103, S104, and S105 in FIG. 6, step S107 in FIG. 8, step S108 in FIG. 9, steps S302-S305 in FIG. 15, and step S306 in FIG. , S307, S305a, and S305b, steps S308, S309, S305c, and S305d in FIG. 18.
  • the transceiver pin 202 is used to perform step S101 in FIG. 6, step S106 in FIG. 8, steps S201 and S202 in FIG. 10, step S301 in FIG. 15, and steps S401 and S402 in FIG.
  • the embodiment of the present application also provides a computer-readable storage medium in which computer instructions are stored; when the computer-readable storage medium runs on an ML entity, the ML entity is made to execute as shown in Figure 6 , Figure 8, Figure 9, Figure 10, Figure 15, Figure 17, Figure 18, or Figure 19.
  • the computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium.
  • the computer instructions may be transmitted from a website, computer, server, or data center. Transmission to another website, computer, server or data center via wired (such as coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (such as infrared, wireless, microwave, etc.).
  • the computer-readable storage medium may be any available medium that can be accessed by a computer, or may include one or more data storage devices such as servers and data centers that can be integrated with the medium.
  • the usable medium may be a magnetic medium (for example, a floppy disk, a hard disk, and a magnetic tape), an optical medium, or a semiconductor medium (for example, a solid state disk (SSD)).
  • the embodiment of the present application also provides a computer program product containing computer instructions, when it runs on the ML entity, the ML entity can execute Figure 6, Figure 8, Figure 9, Figure 10, Figure 15, Figure 17, Figure 18. , Or the method shown in Figure 19.

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Abstract

本申请提供一种通信保护方法及装置，涉及通信技术领域，用于避免ML实体在一个链路上接收信号，在另一个链路上发送信号的情况发生。该方法包括：ML实体在第一链路上侦听到第一PPDU；若第一PPDU是intra-BSS PPDU，且第一PPDU的持续时间字段的取值大于第二链路的目标NAV的数值，则ML实体将第二链路的目标NAV的数值更新为第一PPDU的持续时间字段的取值，第二链路为所述ML实体所支持的多个链路中除了第一链路之外的任意一个链路。

Description

通信保护方法及装置
本申请要求于2019年07月05日提交国家知识产权局、申请号为201910606221.6、发明名称为“通信保护方法及装置”的中国专利申请的优先权，其全部内容通过引用结合在本申请中。
技术领域
本申请涉及通信技术领域，尤其涉及通信保护方法及装置。
背景技术
为了达到极高吞吐率的技术目标，电气和电子工程师协会(institute of electrical and electronics engineers，IEEE)802.11be标准将多链路(multi-link，ML)作为关键技术之一。支持ML技术的ML实体具有在多个频段发送和接收的能力，从而ML实体可以利用更大的带宽进行数据传输，有利于显著提升吞吐率。其中，ML实体在一个频段上进行数据传输的空间路径可以称为一个链路。
当ML实体所支持的多个频段之间的频率间隔较近时，ML实体在一个频段上发送信号会影响该ML实体在另一个频段上接收信号，影响ML实体的正常通信。目前，针对ML实体在多个链路上接收和发送不同步的问题，业界尚未提出相应的解决方案。
发明内容
本申请提供一种通信保护方法及装置，用于解决ML实体在多个链路上接收和发送不同步的问题。
第一方面，提供一种通信保护方法，该方法应用于ML实体，ML实体支持多个链路。方法包括：ML实体在第一链路上侦听到第一物理层协议数据单元(physical layer protocol data unit，PPDU)；若第一PPDU是基本服务集内(intra-BSS)PPDU，且第一PPDU的持续时间字段的取值大于第二链路的目标NAV的数值，则ML实体将第二链路的目标网络分配向量(network allocation vector，NAV)的数值更新为第一PPDU的持续时间字段的取值，第二链路为ML实体所支持的多个链路中除了第一链路之外的任意一个链路。
基于上述技术方案，若ML实体在第一链路上侦听到intra-BSS的其他站点发送的第一PPDU，且第一PPDU的持续时间字段的取值大于第二链路的目标NAV的数值，则ML实体将第二链路的目标NAV的数值更新为第一PPDU的持续时间字段的取值，从而保证在第一PPDU传输完毕之后，ML实体在第一PPDU的持续时间字段所指示的时长内不会发送PPDU，从而不会导致同一BSS内的其他ML实体发生在一个链路上接收PPDU，同时在另一个链路上发送PPDU的情况，也即能够保证其他ML实体在多个链路上同步地发送信号/接收信号。
一种可能的设计中，该方法还包括：若第一PPDU是基本服务集间(inter-BSS)PPDU，则ML实体不更新第二链路的目标NAV的数值；或者，若第一PPDU是intra-BSS PPDU，且第一PPDU的持续时间字段的取值小于等于第二链路的目标NAV的数值，则ML实体不更新第二链路的目标NAV的数值。
一种可能的设计中，该方法还包括：ML实体在第一链路上侦听到无竞争结束 (Contention-Free End，CF-End)帧；若CF-end帧是intra-BSS PPDU，且第二链路的目标NAV的数值是根据第一PPDU的持续时间字段的取值来更新的，则ML实体将第二链路的目标NAV的数值设置为0。应理解，ML实体的第二链路的目标NAV根据在第一链路侦听到的第一PPDU的持续时间字段的取值更新，以保证ML实体不在第二链路上发送数据，避免影响同一BSS内的其他ML实体在第一链路上的通信。这种情况下，若ML实体在第一链路上侦听到同一BSS内的CF-End帧，说明同一BSS内的其他ML实体在第一链路上的通信已结束，因此ML实体可以将目标NAV的数值设置为0，以使得ML实体在第二链路上的虚拟载波监听不受第一链路上的通信的影响，避免延误ML实体在第二链路上的信道竞争，有利于提高ML实体对第二链路的利用率。
一种可能的设计中，该方法还包括：若ML实体在第一链路上在预设时长内未侦听到第二PPDU，且第二链路的目标NAV的数值是根据第一PPDU的持续时间字段的取值来更新的，则ML实体重新设置第二链路的目标NAV，第二PPDU和第一PPDU来自于同一个站点。应理解，若在预设时长内，ML实体未在第一链路上侦听到第一PPDU的发送端发送的第二PPDU，则说明第一PPDU的发送端可能不在第一链路上占用信道，因此ML实体可以在第一链路上发起信道竞争，以在第一链路上发送第一PPDU。这种情况下，若目标NAV是根据所述第一PPDU的持续时间字段的取值来更新的，则ML实体重新设置目标NAV，以使得ML实体在第二链路上的虚拟载波监听不受第一链路上的通信的影响，避免延误ML实体在第二链路上的信道竞争，有利于提高ML实体对第二链路的利用率。
一种可能的设计中，ML实体重新设置第二链路的目标NAV，包括：ML实体设置第二链路的目标NAV的数值为0；或者，ML实体设置第二链路的目标NAV的数值为第一数值，第一数值所确定的结束时刻与第二数值所确定的结束时刻相同，第二数值是在目标NAV根据第一PPDU的持续时间字段的取值更新之前目标NAV的数值。
一种可能的设计中，预设时长＝(2×aSIFSTime)+(第一PPDU响应帧传输时长)+ aRxPHYStartDelay+(2×aSlotTime)。其中，aSIFSTime表示短帧间间隔(short inter-frame space，SIFS)的时长，aRxPHYStartDelay表示预设延迟的时长，aSlotTime表示一个时隙的时长。
一种可能的设计中，第一PPDU中承载请求发送(request to send，RTS)帧，响应帧为清除发送(clear to send，CTS)帧。
一种可能的设计中，若ML实体为ML非接入点(none access point，non-AP)实体，则目标NAV包括以下情形之一：(1)若ML non-AP实体在第二链路上配置有intra-BSS NAV和基本basic NAV，则目标NAV为intra-BSS NAV；(2)若ML non-AP实体在第二链路上配置有intra-BSS NAV、basic NAV、以及第一NAV，则目标NAV为第一NAV。
一种可能的设计中，若ML实体为ML接入点(access point，AP)实体，则目标NAV包括以下情形之一：(1)若ML AP实体在第二链路上配置有intra-BSS NAV和basic NAV，则目标NAV为intra-BSS NAV；(2)若ML AP实体在第二链路上仅配置有intra-BSS NAV、basic NAV和第一NAV，则目标NAV为第一NAV；(3)若ML AP实体在第二链路上配置有第一NAV和第二NAV，则目标NAV为第一NAV。
第二方面，提供一种通信保护方法，该方法应用于ML实体，ML实体支持多个链路。该方法包括：ML实体在第一链路上发送第一PPDU，第一PPDU包括持续时间字段，第 一PPDU所包括的持续时间字段用于指示第一时段的时长；ML实体在第二链路上发送MAC帧，媒体接入控制(media access control，MAC)帧用于指示第二时段的时长，第一时段的结束时刻与第二时段的结束时刻相同，第二时段内第二链路上的intra-BSS站点禁止发送第二PPDU，第二链路是ML实体所支持的多个链路中除了第一链路之外的任意一个链路。
基于上述技术方案，当ML实体在第一链路上发送PPDU时，ML实体在第二链路上发送MAC帧，以使得第二链路上同一BSS内的其他站点在第一时段的结束时刻之前不会发送PPDU。这样一来，保证该ML实体不会发生在第一链路上发送PPDU，在第二链路上接收PPDU的情况，保证ML实体在多个链路上能够同步地发送信号/接收信号。
一种可能的设计中，MAC帧为公告帧或者静默时间阶段(quiet time period，QTP)帧。
一种可能的设计中，公告帧的持续时间字段的取值等于第二时段的时长，公告帧的持续时间字段用于设置intra-BSS的站点所维护的NAV的数值，公告帧的持续时间字段不用于设置重叠基本服务集(overlapping basic service set，OBSS)的站点所维护的NAV的数值。
一种可能的设计中，公告帧包括持续时间字段以及时长字段，时长字段用于设置intra-BSS的站点所维护的NAV的数值，持续时间字段的取值为0，时长字段的取值等于第二时段的时长。
第三方面，提供一种通信保护方法，该方法应用于ML实体，ML实体支持多个链路。该方法包括：ML实体在第一链路上侦听到PPDU的开始；ML实体在第二链路上停止第一退避计数器的计数，第二链路是ML实体所支持的多个链路中除了第一链路之外的任意一个链路；ML实体判断PPDU是intra-BSS PPDU，还是inter-BSS PPDU；若PPDU是intra-BSS PPDU，则ML实体在PPDU传输完毕之后，在第二链路上继续回退；若PPDU是inter-BSS PPDU，则ML实体在第二链路上继续回退。
基于上述技术方案，ML实体在第一链路上侦听到PPDU的开始后，ML实体在第二链路上暂停第一退避计数器的计数。在PPDU是intra-BSS PPDU的情况下，ML实体在该PPDU传输完毕之后，才继续回退。从而，在第一链路上的PPDU传输过程中，ML实体不会在第二链路上发送PPDU，避免导致同一BSS内的其他ML实体发生在第一个链路上接收信号，在另一个链路上发送信号的情况。另外，当ML实体确定该PPDU是inter-BSS PPDU时，ML实体立即继续回退，从而保证了ML实体能够正常在第二链路上进行信道接入。
一种可能的设计中，ML实体在PPDU传输完毕之后，在第二链路上继续回退，包括：ML实体在第一时刻之后，在第二链路上继续回退，第一时刻为PPDU的传输结束时刻；或者，ML实体在第二时刻之后，在第二链路上继续回退，第二时刻为PPDU对应的响应帧的传输结束时刻；或者，ML实体在第三时刻之后，在第二链路上继续回退，第三时刻为PPDU的持续时间字段所确定的结束时刻。
一种可能的设计中，在ML实体在第二链路上停止第一退避计数器的计数之后，该方法还包括：ML实体在第二链路上配置第二退避计数器，第二退避计数器的初始值为第一退避计数器的当前值；若第二链路在当前时刻处于空闲状态，则每当第二链路在一个时隙内处于空闲状态，则ML实体将第二退避计数器的计数值减1；若第二链路在当前时刻处 于繁忙状态，则ML实体等待第二链路的空闲时间达到第二帧间间隔；在第二链路的空闲时间达到第二帧间间隔之后，每当第二链路在一个时隙内处于空闲状态，则ML实体将第二退避计数器的计数值减1。
一种可能的设计中，该方法还包括：在第二退避计数器的计数值减到0之后，ML实体保持第二退避计数器的计数值为0。
一种可能的设计中，该方法还包括：当第二退避计数器的计数值减到0时，ML实体重新设置第二退避计数器的计数值。
一种可能的设计中，ML实体重新设置第二退避计数器的计数值，包括：ML实体根据加倍后的竞争窗口，重新设置第二退避计数器的计数值；或者，ML实体根据竞争窗口，重新设置第二退避计数器的计数值；或者，ML实体根据竞争窗口的最小值，重新设置第二退避计数器的计数值。
一种可能的设计中，若PPDU是inter-BSS PPDU，则ML实体在第二链路上继续回退，包括：若PPDU是inter-BSS PPDU，则ML实体以第二退避计数器的计数值更新第一退避计数器的计数值，并基于第一退避计数器，在第二链路上继续回退。基于该设计，当ML实体确定PPDU是inter-PPDU时，ML实体再以第二退避计数器的计数值设置第一退避计数器的计数值，从而使得第一退避计数器不受之前暂停的影响。这样一来，在PPDU是inter-BSS PPDU的情况下，ML实体在第二链路上的退避流程是不受影响的，从而避免ML实体在信道竞争中处于劣势，保证ML实体对于第二链路的使用。
第四方面，提供一种通信保护方法，该方法应用于ML non-AP实体，ML non-AP实体支持多个链路。该方法包括：ML non-AP实体在第一链路上侦听到第一PPDU；若第一PPDU的接收端是ML non-AP实体所关联的ML AP实体，则ML non-AP实体在第二链路上发送第二PPDU，第二链路是ML non-AP实体所支持的多个链路中除了第一链路之外的任意一个链路，第一PPDU的结束时刻与第二PPDU的结束时刻相同。
基于上述技术方案，若ML non-AP实体在第一链路上侦听到第一PPDU，且第一PPDU是发送给ML non-AP实体所关联的ML AP实体的，则ML non-AP实体在第二链路上发送第二PPDU。由于第二PPDU的结束时刻与第一PPDU的结束时刻相同，从而ML AP实体可以在同一时刻发送第二PPDU的块确认(block ack，BA)帧和第一PPDU的BA帧。这样一来，一方面，避免了ML AP实体发生在一个链路上发送信号，在另一个链路上接收信号的情况。另一方面，ML non-AP实体在第二链路上发送第二PPDU，有利于提高第二链路的利用率。
一种可能的设计中，ML non-AP实体在第二链路上发送第二PPDU，包括：ML non-AP实体在第二链路上执行退避流程；在第二链路上的退避流程结束之后，ML non-AP实体在第二链路上发送第二PPDU。
第五方面，提供一种ML实体，该ML实体可以包括用于执行第一方面至第四方面中任一种设计中所描述的方法/操作/步骤/动作所一一对应的模块。上述模块可以是硬件电路，或者是软件，又或者以硬件电路结合软件实现。
第六方面，提供一种ML实体，该ML实体，该ML实体包括处理器和收发器，该处理器用于执行上述第一方面至第四方面中任一种设计所涉及的通信保护方法中的处理操作。该收发器用于接受处理器的控制，执行上述第一方面至第四方面中任一种设计所涉及 的通信保护方法中的收发操作。
第七方面，提供一种计算机可读存储介质，该计算机可读存储介质用于存储指令，当该指令被计算机读取时，计算机用于执行上述第一方面至第四方面中任一种设计所涉及的通信保护方法。
第八方面，提供一种计算机程序产品，该计算机程序产品包括指令。当计算机读取该指令时，计算机执行上述第一方面至第四方面中任一种可能设计所涉及的通信保护方法。
第九方面，提供一种芯片，该芯片包括处理电路和收发管脚。该芯片支持多个链路。收发管脚，用于在第一链路上侦听到第一PPDU。处理电路，用于在第一PPDU是intra-BSS PPDU，且第一PPDU的持续时间字段的取值大于第二链路的目标NAV的数值的情况下，将第二链路的目标NAV的数值更新为第一PPDU的持续时间字段的取值，第二链路为ML实体所支持的多个链路中除了第一链路之外的任意一个链路。
第十方面，提供一种芯片，该芯片包括处理电路和收发管脚。该芯片支持多个链路。收发管脚，用于在第一链路上发送第一PPDU，第一PPDU包括持续时间字段，第一PPDU所包括的持续时间字段用于指示第一时段的时长。收发管脚，还用于在第二链路上发送MAC帧，MAC帧用于指示第二时段的时长，第一时段的结束时刻与第二时段的结束时刻相同，第二时段内第二链路上的intra-BSS站点禁止发送第二PPDU，第二链路是ML实体所支持的多个链路中除了第一链路之外的任意一个链路。
第十一方面，提供一种芯片，该芯片包括处理电路和收发管脚。该芯片支持多个链路。收发管脚，用于在第一链路上侦听到PPDU的开始。处理电路，用于在第二链路上停止第一退避计数器的计数，并判断PPDU是intra-BSS PPDU，还是inter-BSS PPDU；在PPDU是intra-BSS PPDU的情况下，在PPDU传输完毕之后，在第二链路上继续回退；在PPDU是inter-BSS PPDU的情况下，在第二链路上继续回退。第二链路是该芯片所支持的多个链路中除了第一链路之外的任意一个链路。
第十二方面，提供一种芯片，该芯片包括处理电路和收发管脚。该芯片支持多个链路，收发管脚，用于在第一链路上侦听到第一PPDU。收发管脚，还用于在第一PPDU的接收端是关联的ML AP实体的情况下，在第二链路上发送第二PPDU，第二链路是ML non-AP实体所支持的多个链路中除了第一链路之外的任意一个链路，第一PPDU的结束时刻与第二PPDU的结束时刻相同。
其中，第五方面至第十二方面中任一种设计所带来的技术效果可参考上文所提供的对应的方法中的有益效果，此处不再赘述。
附图说明
图1为本申请实施例提供的一种退避流程的示意图；
图2为本申请实施例提供的一种PPDU的帧结构的示意图；
图3为本申请实施例提供的一种ML实体之间的通信场景的示意图；
图4为本申请实施例提供的一种ML通信场景的示意图；
图5为本申请实施例提供的另一种ML通信场景的示意图；
图6为本申请实施例提供的一种通信保护方法的流程图；
图7为本申请实施例提供的另一种ML通信场景的示意图；
图8为本申请实施例提供的另一种通信保护方法的流程图；
图9为本申请实施例提供的另一种通信保护方法的流程图；
图10为本申请实施例提供的另一种通信保护方法的流程图；
图11为本申请实施例提供的一种公告帧的帧结构的示意图；
图12为本申请实施例提供的一种公告帧的帧结构的示意图；
图13为本申请实施例提供的一种帧公告帧的帧结构的示意图；
图14为本申请实施例提供的另一种ML通信场景的示意图；
图15为本申请实施例提供的另一种通信保护方法的流程图；
图16(a)为本申请实施例提供的另一种ML通信场景示意图；
图16(b)为本申请实施例提供的另一种ML通信场景示意图；
图16(c)为本申请实施例提供的另一种ML通信场景示意图；
图16(d)为本申请实施例提供的另一种ML通信场景示意图；
图16(e)为本申请实施例提供的另一种ML通信场景示意图；
图16(f)为本申请实施例提供的另一种ML通信场景示意图；
图16(g)为本申请实施例提供的另一种ML通信场景示意图；
图17为本申请实施例提供的另一种通信保护方法的流程图；
图18为本申请实施例提供的另一种通信保护方法的流程图；
图19为本申请实施例提供的一种通信保护方法的流程图；
图20为本申请实施例提供的另一种ML通信场景的示意图；
图21为本申请实施例提供的一种ML实体的结构示意图；
图22为本申请实施例提供的一种ML实体的结构示意图。
具体实施方式
在本申请的描述中，除非另有说明，“/”表示“或”的意思，例如，A/B可以表示A或B。本文中的“和/或”仅仅是一种描述关联对象的关联关系，表示可以存在三种关系，例如，A和/或B，可以表示：单独存在A，同时存在A和B，单独存在B这三种情况。此外，“至少一个”是指一个或多个，“多个”是指两个或两个以上。“第一”、“第二”等字样并不对数量和执行次序进行限定，并且“第一”、“第二”等字样也并不限定一定不同。
需要说明的是，本申请中，“示例性的”或者“例如”等词用于表示作例子、例证或说明。本申请中被描述为“示例性的”或者“例如”的任何实施例或设计方案不应被解释为比其他实施例或设计方案更优选或更具优势。确切而言，使用“示例性的”或者“例如”等词旨在以具体方式呈现相关概念。
为了便于理解本申请的技术方案，下面先对本申请所涉及的术语进行简单介绍。
1、基本服务集(basic service set，BSS)
BSS用于描述无线局域网(wireless local area networks，WLAN)中一组能够相互通信的设备。WLAN中可以包括多个BSS。每一个BSS具有唯一的标识，称为基本服务集标识符(BSSID)。
一个BSS可以包括多个站点(station，STA)。站点包括AP和非接入点的站点(none access point station，non-AP STA)。可选的，一个BSS可以包含一个AP和多个关联该AP的non-AP STA。
AP也称之为无线访问接入点或者热点。AP可以是无线路由器、无线收发机、无线交 换机等。
non-AP STA可以有不同的名称，例如用户单元、接入终端、移动站、移动台、移动设备、终端、用户设备等。在实际应用中，STA可以是蜂窝电话、智能手机、无线本地环路(wireless local loop，WLL)，以及其它具有无线局域网通信功能的手持设备、计算机设备等。
2、退避机制
IEEE 802.11标准支持多个用户共享同一传输介质，由发送者在发送数据前先进行传输介质的可用性检测。IEEE 802.11标准采用载波侦听多路访问/碰撞避免(carrier sense multiple access with collision avoidance，CSMA/CA)来实现信道的竞争。其中，为了避免碰撞，CSMA/CA采用了退避机制。
下面对单信道上的退避机制进行说明。在设备发送消息之前，设备可以从0到竞争窗口(contention window，CW)之间选择一个随机数，并以该随机数作为退避计数器的初始值。在信道的空闲时间达到仲裁帧间间隔(arbitration interframe space，AIFS)之后，当信道每空闲一个时隙(timeslot)时，退避计数器的计数值减1。在退避计数器的计数值减为0之前，若信道在某一个timeslot的状态为繁忙，则退避计数器暂停计数。之后，若信道从繁忙状态转为空闲状态后，并且信道的空闲时间达到AIFS之后，退避计数器恢复计数。当退避计数器的计数值为0时，退避流程结束，设备可以开始数据传输。
结合图1进行举例说明，假设退避计数器的初始值为5，在信道的空闲时间达到AIFS后，退避计数器开始回退。每当信道在一个时隙中处于空闲状态，退避计数器的计数值减1，直至退避计数器的计数值为0。在退避计数器的计数值为0后，设备可以在该信道上发送PPDU。
3、NAV
NAV用于虚拟载波监听中，NAV相当于一个计数器，用于记录站点对信道占用的时间。NAV的值会随着时间推移不断减少，但是在NAV的值减到零之前，站点始终认为信道繁忙而停止信道竞争和数据发送。
目前，non-AP STA具有两个NAV，分别是intra-NAV和basic NAV。其中，intra-NAV根据intra-BSS PPDU更新。basic NAV根据inter-BSS PPDU来更新，或者根据不能被分类为intra-BSS或者inter-BSS的PPDU来更新。
AP可以具有两个NAV，也可以只有一个AP。在AP配置两个NAV的情况下，AP的两个NAV分别是intra-NAV和basic NAV。
应理解，在密集部署的场景下，站点维护两个NAV是有益的。站点通过维护两个NAV，可以保护intra-BSS的站点发送的帧，也可以避免来自inter-BSS的站点发送的帧的干扰。
4、PPDU
如图2所示，为802.11ax标准中PPDU的帧结构的示意图。PPDU包括：传统短训练域(legacy-short training field，L-STF)、传统长训练域(legacy-long training field，L-LTF)、传统信令域(legacy-signal field，L-SIG)、重复传统信令域(repeated legacy-signal field，RL-SIG)、高效信令字段A(high efficient-signal field A，HE-SIG A)、高效信令字段B(high efficient-signal field B，HE-SIG B)、高效短训练域(high efficient-short training field，HE-STF)、高效长训练域(high efficient-long training field，HE-LTF)、数据(data)、以及数据分组扩 展(packet extension，PE)。
其中，L-STF用于自动增益控制、序列同步和粗频偏估计。
5、intra-BSS PPDU、inter-BSS PPDU
对于一个站点来说，该站点侦听到的PPDU所属的BSS与该站点所关联的BSS是同一个BSS，或者，该站点侦听到的PPDU的接收端/发送端与该站点属于同一个BSS，则该PPDU是intra-BSS PPDU。示例性的，若该站点侦听到的PPDU中的BSS color/BSSID与该站点关联的BSS的BSScolor/BSSID相同，则该PPDU是intra-BSS PPDU。
对于一个站点来说，该站点侦听到的PPDU所属的BSS与该站点所关联的BSS不是同一个BSS，或者，该站点侦听到的PPDU的接收端/发送端与该站点不属于同一个BSS，则该PPDU是inter-BSS PPDU。示例性的，若该站点侦听到的PPDU中的BSS color/BSSID与该站点关联的BSS的BSScolor/BSSID不相同，则该PPDU是inter-BSS PPDU。
上述站点判断PPDU是intra-BSS PPDU还是inter-BSS PPDU的方法仅是示例，详细描述可参见现有技术。
6、ML实体
ML实体具有在多个频段上的发送和接收的能力。示例性的，上述多个频段包括但不限于：2.4GHz频段、5GHz频段、以及6GHz频段。ML实体在一个频段上进行数据传输的空间路径可以称为一个链路。也就是说，ML实体支持多链路通信。
应理解，对于ML实体来说，ML实体支持的每一个链路均对应一个频段。
ML实体也可以称为ML STA实体。ML实体包括多个STA。ML实体中的每一个STA可以建立一个链路进行通信。如图3所示，ML实体A包含站点A1-站点AN，ML实体B包含站点B1-站点BN。站点A1和站点B1之间通过链路1进行通信，站点A2和站点B2之间通信链路2进行通信，以此类推，站点AN和站点BN之间通过链路N进行通信。
需要说明的是，ML实体中的多个STA可以具有相同的MAC地址，也可以具有不相同的MAC地址。ML实体中的多个STA可以位于同一物理位置，也可以位于不同的物理位置。
若ML实体中的STA为AP，则该ML实体可以称为ML AP实体。若ML实体中的STA为non-AP STA，则该ML实体可以称为ML non-AP STA实体，或者ML non-AP实体。在本申请实施例中，若未作特殊说明，ML实体既可以为ML AP实体，也可以为ML non-AP实体。
ML non-AP实体中一个链路上的non-AP STA可以与ML AP实体中同一链路上的AP相关联，以使得ML non-AP实体中一个链路上的non-AP STA可以与ML AP实体中同一链路上的AP之间进行通信。
应理解，ML AP实体与ML non-AP实体之间可以建立关联关系，以保证ML AP实体与ML non-AP实体之间的正常通信。
需要说明的是，ML AP实体与ML non-AP实体之间的关联关系，包括：ML AP实体在一个链路上的站点与ML non-AP实体在同一链路上的站点之间的关联关系。
本申请实施例不对ML non-AP实体与ML AP实体之间建立关联关系的实现方式进行限定。例如，ML non-AP实体与ML AP实体在一个链路上建立该链路上的关联关系；又或者，ML non-AP实体与ML AP实体在一个链路上建立ML non-AP实体与ML AP实体之 间在多个链路上的关联关系。
ML non-AP实体与ML AP实体建立一个链路上的关联关系，其具体实现方式可以参考现有技术中的AP与non-AP STA之间建立关联关系的实现方式，在此不再赘述。
7、SL实体
SL实体是指仅支持一个链路的STA。SL实体可以为传统(legacy)STA，也即为仅支持已有802.11标准，而不支持下一代802.11标准的STA。
以上是对本申请所涉及的技术术语的简单介绍，以下不再赘述。
下面以举例的方式来说明ML实体在多个链路上接收和发送不同步的情况。
结合图4进行举例说明，ML AP实体在第一链路上向ML non-AP实体1发送PPDU#1。由于ML non-AP实体2不知道ML AP实体正在第一链路上发送PPDU#1，因此ML non-AP实体2可能在第二链路上向ML AP实体发送PPDU#2。在这种情况下，ML AP实体在第一链路上发送PPDU#1会影响到ML AP实体在第二链路上接收PPDU#2，导致PPDU#2传输失败。
结合图5进行举例说明，ML non-AP实体1在第一链路上向ML AP实体发送PPDU。由于ML non-AP实体2不知道ML non-AP实体1正在第一链路上发送PPDU#1，因此ML non-AP实体2可能在第二链路上向ML AP实体发送PPDU#2。PPDU#2的传输时间短于PPDU#1的传输时间。如果ML AP实体在第二链路上发送BA帧，则会影响到ML实体在第一链路上接收PPDU#1，导致PPDU#1传输失败。而如果ML AP在第二链路上不发送BA帧，则ML non-AP实体2会由于未收到BA帧而认为PPDU#2传输失败。
应理解，ML实体在多个链路上接收和发送不同步，具体是指：ML实体在一部分链路上发送信号，同时该ML实体在另一部分链路上接收信号。
由于ML实体在一个链路上发送信号会影响到ML实体在另一个链路上接收信号，因此需要避免ML实体在多个链路上接收和发送不同步。针对这一技术问题，本申请实施例提供如下技术方案，其具体内容可参见下文。
本申请的技术方案应用于WLAN，WLAN采用的标准可以为IEEE的802.11标准，例如802.11ax标准、以及下一代的802.11标准等。本申请的技术方案适用的场景包括：ML实体与ML实体之间的通信场景、ML实体与SL实体之间的通信场景。
示例性的，ML实体与ML实体之间的通信场景可以为：ML non-AP实体与ML AP实体之间的通信场景；或者，ML non-AP实体与ML non-AP实体之间的通信场景；又或者，ML AP实体与ML AP实体之间的通信场景。
示例性的，ML实体与SL实体之间的通信场景可以为：ML non-AP实体与传统AP之间的通信场景；或者，ML AP实体与传统non-AP STA之间的通信场景；又或者，ML AP实体与传统AP之间的通信场景；又或者，ML non-AP实体与传统non-AP STA之间的通信场景。
下面结合说明书附图，对本申请实施例所提供的技术方案进行具体介绍。
如图6所示，为本申请实施例提供的一种通信保护方法，该方法包括以下步骤：
S101、ML实体在第一链路上侦听到第一PPDU。
其中，ML实体可以支持多个链路。第一链路是ML实体所支持的多个链路中的任意一个链路。
作为一种实现方式，ML实体的第一链路的站点在第一链路上侦听到第一PPDU。
S102、ML实体判断第一PPDU是intra-BSS PPDU，还是inter-BSS PPDU。
作为一种实现方式，ML实体的第一链路的站点判断第一PPDU是intra-BSS PPDU，还是inter-BSS PPDU。其中，第一PPDU是intra-BSS PPDU，还是inter-BSS PPDU的判断方法可以参考现有技术，在此不再赘述。
在第一PPDU是intra-BSS PPDU的情况下，ML实体会执行下述步骤S103。在所述PPDU是inter-BSS PPDU的情况下，ML实体会执行下述步骤S105。
S103、在第一PPDU是intra-BSS PPDU的情况下，ML实体判断第一PPDU的持续时间(duration)字段的取值是否大于第二链路的目标NAV的当前值。
其中，第二链路是ML实体所支持的多个链路中除了第一链路之外的其他链路。也即，第一链路和第二链路是不同的两个链路。
需要说明的是，第一PPDU的持续时间字段的取值用于指示第一PPDU的发送端占用第一链路上的信道的时间。
在本申请实施例中，第二链路的目标NAV可以用于记录站点在第二链路上被禁止主动发起竞争的时间。第二链路的目标NAV可以复用当前标准中的NAV，或者可以为新配置的一个NAV。
可选的，在ML实体为ML non-AP实体的情况下，第二链路的目标NAV可以采用以下情形之一：
情形一、第二链路的目标NAV复用第二链路的intra-NAV。这种情况下，在第二链路上，ML non-AP实体包括：intra-NAV和basic NAV。
情形二、第二链路的目标NAV为新配置的一个NAV。这种情况下，在第二链路上，ML non-AP实体包括：intra-NAV、basic NAV、以及第一NAV。其中，第一NAV即为目标NAV，第一NAV也可以称为ML NAV。
可选的，在ML实体为ML AP实体的情况下，第二链路的目标NAV可以采用以下情形之一：
情形一、第二链路的目标NAV复用第二链路的intra-NAV。在这种情况下，在第二链路上，ML AP实体包括：intra-NAV和basic NAV。
情形二、第二链路的目标NAV为新配置的一个NAV。在这种情况下，在第二链路上，ML AP实体包括：intra-NAV、basic NAV、以及第一NAV；或者，ML AP实体包括：第一NAV和第二NAV。其中，第一NAV即为目标NAV。第二NAV是当前标准中AP仅配置一个NAV的场景下，AP所配置的NAV。
需要说明的是，在一个链路上，若ML实体配置了多个NAV，则多个NAV中任何一个NAV的数值不为0，则虚拟载波侦听的结果为链路繁忙，因此ML实体在该链路上的退避流程被挂起，ML实体不能在该链路上发送PPDU。
作为一种实现方式，ML实体的第二链路的站点获取到ML实体的第一链路的站点对于第一PPDU是否是intra-BSS PPDU的判断结果。在第一PPDU是intra-BSS PPDU的情况下，ML实体的第二链路的站点进一步从ML实体的第一链路的站点获取到第一PPDU的持续时间字段的取值。之后，ML实体的第二链路的站点判断第一PPDU的持续时间字段的取值是否大于第二链路的目标NAV的当前值。
在第一PPDU的持续时间字段的取值大于第二链路的目标NAV的当前值的情况下，ML实体执行下述步骤S104。在所述PPDU的持续时间字段的取值小于等于第二链路的目标NAV的当前值的情况下，ML实体执行下述步骤S105。
S104、在第一PPDU的持续时间字段的取值大于第二链路的目标NAV的数值的情况下，ML实体将第二链路的目标NAV的数值更新为第一PPDU的持续时间字段的取值。
作为一种实现方式，ML实体的第二链路的站点将第二链路的目标NAV的数值更新为第一PPDU的持续时间字段的取值。举例来说，第二链路的目标NAV的当前值为10，第一PPDU的持续时间字段的取值为12，则ML实体的第二链路的站点将第二链路的目标NAV的数值更新为12。
S105、ML实体不更新第二链路的目标NAV的数值。
作为一种实现方式，ML实体的第二链路的站点不更新第二链路的目标NAV的数值。
基于图6所示的技术方案，若ML实体在第一链路上侦听到intra-BSS的其他站点发送的第一PPDU，且第一PPDU的持续时间字段的取值大于第二链路的目标NAV的数值，则ML实体将第二链路的目标NAV的数值更新为第一PPDU的持续时间字段的取值，从而保证在第一PPDU传输完毕之后，ML实体在第一PPDU的持续时间字段所指示的时长内不会发送PPDU，从而不会导致同一BSS内的其他ML实体发生在一个链路上接收PPDU，同时在另一个链路上发送PPDU的情况，保证同一BSS内的其他ML实体的正常通信。
结合图7进行举例说明，ML non-AP实体1在第一链路上侦听到PPDU#1，PPDU#1是ML AP发送给ML non-AP实体2实体的。ML non-AP实体1的第一链路的站点、ML non-AP实体2的第一链路的站点、以及ML AP实体的第一链路的站点属于同一BSS。在这种情况下，ML non-AP实体1以PPDU#1的持续时间字段的取值，设置第二链路的目标NAV。从而ML non-AP实体1在目标NAV的数值到0之前，ML non-AP实体1不会在第二链路上向ML AP实体发送PPDU。从而，当ML AP实体在第一链路上向ML non-AP实体2发送PPDU#1时，ML AP实体不需要在第二链路上接收PPDU#2。这样一来，保证ML AP实体的正常通信。需要说明的是，使用PPDU#1的持续时间字段的取值设置第二链路的目标NAV不必在PPDU#1传输结束之后进行，如果该持续时间字段的取值可以在PPDU#1传输过程中获得，则可以在获得持续时间的取值之后立即设置第二链路的目标NAV。比如当PPDU#1中承载的是A-MPDU，则在第一个MPDU接收完毕之后即可以获取持续时间的取值；再比如PPDU1的SIG字段中承载有TXOP Duration字段，则可以在SIG字段接收完毕之后通过TXOP Duration字段获得持续时间字段的取值。
作为一种可选的实施例，基于图6所示的技术方案，如图8所示，在步骤S104之后，该通信保护方法还包括步骤S106-S107。
S106、ML实体在第一链路上侦听到CF-End帧。
其中，CF-End帧用于指示无竞争周期的结束。在无竞争周期结束的情况下，同一BSS内的站点可以发起信道竞争，以接入信道。
作为一种实现方式，ML实体的第一链路的站点在第一链路上侦听到CF-End帧。
在侦听到CF-End帧之后，ML实体的第一链路的站点会判断该CF-End帧是否是intra-BSS PPDU。若CF-End帧是intra-BSS PPDU，则intra-BSS内的站点未占用第一链路上的信道，因此ML实体的第一链路的站点可以在第一链路上进行信道接入。
可以理解的是，CF-End帧是intra-BSS PPDU，说明该CF-End帧属于ML实体的第一链路的站点所关联的BSS。
示例性的，ML实体的第一链路的站点会判断该CF-End帧是否是intra-BSS PPDU，包括：若CF-End帧所携带的BSSID与ML实体的第一链路的站点所关联的BSS的BSSID相同，则ML实体的第一链路的站点可以确定该CF-End帧是intra-BSS PPDU；否则，ML实体的第一链路的站点可以确定该CF-End帧不是intra-BSS PPDU。应理解，判断CF-End帧是否是intra-BSS PPDU还有其他实现方式，本申请实施例不限于此。
S107、若CF-End帧是intra-BSS PPDU，且目标NAV的数值是根据第一PPDU的持续时间字段的取值来更新，则ML实体将第二链路的目标NAV的数值设置为0。
作为一种实现方式，在CF-End帧是intra-BSS PPDU的情况下，ML实体的第二链路的站点将第二链路的目标NAV的数值设置为0。
基于图8所示的技术方案，ML实体的第二链路的目标NAV根据在第一链路侦听到的第一PPDU的持续时间字段的取值更新，以保证ML实体不在第二链路上发送数据，避免影响同一BSS内的其他ML实体在第一链路上的通信。这种情况下，若ML实体在第一链路上侦听到同一BSS内的CF-End帧，说明同一BSS内的其他ML实体在第一链路上的通信已结束，因此ML实体可以将目标NAV的数值设置为0，以使得ML实体在第二链路上的虚拟载波监听不受第一链路上的通信的影响，避免延误ML实体在第二链路上的信道竞争，有利于提高ML实体对第二链路的利用率。
作为一种可选的实施例，基于图6所示的技术方案，如图9所示，在步骤S104之后，该通信保护方法还包括步骤S108。
S108、若所述ML实体在预设时长内在第一链路上未侦听到第二PPDU，且所述第二链路的目标NAV的数值是根据所述第一PPDU的持续时间字段的取值来更新的，则所述ML实体重新设置第二链路的目标NAV。
其中，第二PPDU和第一PPDU来自于同一个站点。
在具体实现中，若ML实体在预设时长内在第一链路上未侦听到任何一个PPDU，则该ML实体确定在预设时长内在第一链路上未侦听到第二PPDU。若ML实体在预设时长内在第一链路上侦听到一个或多个PPDU，若所述一个或多个PPDU的发送站点与第一PPDU的发送站点不同，则该ML实体确定第一PPDU与所述一个或多个PPDU来自于不同的站点，进而该ML实体确定在预设时长内在第一链路上未侦听到第二PPDU。
可选的，预设时长＝(2×aSIFSTime)+(第一PPDU响应帧的传输时长)+aRxPHYStartDelay+(2×aSlotTime)。
其中，aSIFSTime表示SIFS的时长。
aSlotTime表示一个时隙的时长。aSlotTime一般为9微秒。
应理解，在第一PPDU承载RTS帧的情况下，该第一PPDU响应帧可以为CTS帧，这种情况下第一PPDU响应帧的传输时长就是CTS帧的传输时长，通常记作CTS_Time。需要说明的是，CTS帧的传输时长可以根据CTS帧的长度以及接收到的最近用于更新NAV的RTS帧的数据传输速率来确定。
aRxPHYStartDelay表示预设延迟的时长。其中，预设延迟是指接收天线接收到PPDU的开始到原语PHY-RXSTART.indication发布之间的延迟。
需要说明的是，在不同标准中，aRxPHYStartDelay对应不同的取值。例如，在IEEE 802.11a标准中，aRxPHYStartDelay为20微秒。在IEEE 802.11n标准中，aRxPHYStartDelay为28微秒。在IEEE 802.11ax标准中，aRxPHYStartDelay为40微秒。
在本申请实施例，所述ML实体重新设置第二链路的目标NAV，可以采用以下任一种实现方式：
方式一、ML实体将第二链路的目标NAV的数值设置为0。
方式二、ML实体将第二链路的目标NAV的数值设置为第一数值，第一数值所确定的结束时刻与第二数值所确定的结束时刻相同，第二数值是在目标NAV根据第一PPDU的持续时间字段的取值更新之前目标NAV的数值。
举例说明，在T1时刻，假设第一PPDU的持续时间字段的取值为L1，第二链路的目标NAV的当前值为L2，L1大于L2，因此ML实体将第二链路的目标NAV的数值更新为L1。这种情况下，目标NAV的第二数值即为L2，第二数值所确定的结束时刻即为T1+L2时刻。经过L3时间后，在T1+L3时刻，若ML实体将第二链路的目标NAV的数值设置为第一数值，由于第一数值的结束时刻同样为T1+L2时刻，则第一数值为L2-L3。
基于图9所示的技术方案，若在预设时长内，ML实体未在第一链路上侦听到第一PPDU的发送端发送的第二PPDU，则说明第一PPDU的发送端可能不在第一链路上占用信道，因此ML实体可以在第一链路上发起信道竞争，以在第一链路上发送第一PPDU。这种情况下，若目标NAV是根据所述第一PPDU的持续时间字段的取值来更新的，则ML实体重新设置目标NAV，以使得ML实体在第二链路上的虚拟载波监听不受第一链路上的通信的影响，避免延误ML实体在第二链路上的信道竞争，有利于提高ML实体对第二链路的利用率。
如图10所示，为本申请实施例提供的一种通信保护方法，该方法包括以下步骤：
S201、ML实体在第一链路上发送第一PPDU。
其中，ML实体可以支持多个链路。第一链路可以是ML实体所支持的多个链路中的任意一个链路。
需要说明的是，所述第一PPDU包括持续时间字段。所述第一PPDU的持续时间字段用于指示第一时段的时长。所述第一时段是所述ML实体在所述第一链路上占用信道的时段。所述第一时段的起始时刻为所述PPDU的传输结束时刻。
作为一种实现方式，ML实体的第一链路的站点在第一链路上发送PPDU。
S202、ML实体在第二链路上发送MAC帧。
其中，第二链路是ML实体所支持的多个链路中除了第一链路之外的其他链路。也即，第一链路和第二链路是不同的两个链路。
所述MAC帧用于指示第二时段的时长。所述第二时段内第二链路上的intra-BSS的站点禁止发送第二PPDU，第二PPDU与第一PPDU不同。所述第二时段的起始时刻是所述MAC帧的传输结束时刻。所述第二时段的结束时刻与所述第一时段的结束时刻相同。
另外，MAC帧的传输起始时刻以及传输结束时刻均在所述第一PPDU的传输结束时刻之前，以保证在所述PPDU传输完毕之前，第二链路上的intra-BSS的站点能够接收到该MAC帧，从而第二链路上的intra-BSS的站点不会在第一时段内发送第二PPDU。
作为一种实现方式，当ML实体的第二链路的站点获知ML实体的第一链路的站点在 第一链路上发送第一PPDU时，ML实体的第二链路的站点在第二链路上发送MAC帧。
在本申请实施例中，所述MAC帧可以为公告帧或者QTP帧。需要说明的是，公告帧是本申请实施例定义的一种新类型的控制帧。
在所述MAC帧为公告帧，所述公告帧有以下两种实现方式：
方式一、所述公告帧包括持续时间字段和时长字段。
公告帧的时长字段用于设置第二链路上的intra-BSS的站点所维护的NAV的数值。公告帧的时长字段不用于设置第二链路上的OBSS的站点所维护的NAV的数值。
也即，第二链路上的intra-BSS的站点会读取公告帧所包括的时长字段，并以该公告帧所包括的时长字段的取值来设置自身维护的NAV的数值。但是，第二链路上的OBSS的站点不会以该公告帧的时长字段的取值来设置自身维护的NAV的数值。
需要说明的是，站点以该公告帧所包括的时长字段的取值来设置自身维护的NAV的数值，具体是指，当公告帧所包括的时长字段的取值大于站点自身维护的NAV的数值，则站点将NAV的数值更新为时长字段的取值。反之，则站点不更新NAV的数值。
上述第二链路上的intra-BSS站点是指与ML实体的第二链路的站点属于同一个BSS的站点。第二链路上的OBSS站点是指与ML实体的第二链路的站点不属于同一个BSS的站点。
在本申请实施例中，公告帧的时长字段的取值等于第二时段的时间长度，从而使得第二链路上的intra-BSS的站点至少在第二时段内不能进行信道接入，以避免第二链路上的intra-BSS站点对该ML实体的通信造成干扰。
示例性的，图11为本申请实施例提供的一种公告帧的示意图。公告帧至少包括以下字段：帧控制(frame control)、持续时间(duration)、接收地址(receiving address，RA)、发送地址(transmitting address，TA)、ML传输时长(ML trans time)、帧校验序列(frame check sequence，FCS)。
图11所示的公告帧中的ML传输时长字段即为上文中所提到的公告帧的时长字段。也即，图11所示的公告帧中的ML传输时长字段用于设置第二链路上的intra-BSS的站点所维护的NAV的数值。
其中，帧控制字段还包括以下字段：协议版本(protocol version)、类型(type)、子类型(subtype)。
可选的，在本申请实施例中，在一个控制帧中的类型字段和子类型字段取预设值时，该控制帧即为本申请实施例所提供的公告帧。
示例性的，表1示出类型字段和子类型字段在不同取值下的含义。结合表1所示，若一个控制帧的类型字段的取值为01，子类型字段的取值为0001，该控制帧即为公告帧。
表1
类型字段的取值 类型描述 子类型字段的取值 子类型描述
01 控制(control) 0000 保留
01 control 0001 ML公告
01 control 0010 触发(trigger)
…… …… …… ……
示例性的，图12为本申请实施例提供的一种公告帧的示意图。该公告帧是包含本申 请定义的一种新类型的高吞吐率(high throughput，HT)控制字段的帧。如图11所示，该公告帧包括以下字段之一：帧控制、持续时间/标识、地址(address)1、地址2、地址3、序列控制(sequence control)、地址4、服务质量(quality of service，QoS)控制(control)、HT控制、帧主体(frame body)、以及FCS。
其中，图12所示的公告帧的持续时间/标识字段相当于上文提到的公告帧的持续时间字段。
HT控制字段包括以下字段之一：控制ID、以及控制信息(control information)。其中，控制ID字段的取值为预设值，以指示该HT控制帧为公告帧。图12所示的公告帧中的控制信息字段相当于上文提到的公告帧的时长字段。也即，图12所示的公告帧中的控制信息字段用于指示第二时段的时长。可选的，控制信息字段可以为16比特。
示例性的，图13为本申请实施例提供的一种公告帧的示意图。该公告帧是包含本申请定义的一种新类型的极高吞吐率(extremely high throughput，EHT)控制字段的帧。如图11所示，该公告帧包括以下字段之一：帧控制、持续时间/标识、地址1、地址2、地址3、序列控制、地址4、服务质量控制、EHT控制、帧主体、以及FCS。
其中，图13所示的公告帧中的持续时间/标识字段相当于上文提到的公告帧的持续时间字段。
EHT控制字段包括以下字段之一：控制ID、以及控制信息(control information)。
其中，控制ID字段的取值为预设值，以指示该EHT控制帧为公告帧。示例性的，预设值可以为7。
图13所示的公告帧中的控制信息字段相当于上文提到的公告帧中的时长字段。也即，图13所示的公告帧中的控制信息字段用于指示第二时段的时长。可选的，控制信息字段可以为16比特。
方式二、所述公告帧包括持续时间字段。所述持续时间字段用于使第二链路上的intra-BSS的站点设置NAV。也即，第二链路上的intra-BSS的站点会读取公告帧所包括的时长字段，并以该公告帧所包括的时长字段的取值来设置自身维护的NAV。但是，第二链路上的OBSS的站点不会以该公告帧所包括的时长字段的取值来设置自身维护的NAV。
在本申请实施例中，所述公告帧所包括的持续时间字段的取值等于所述第二时段的时间长度，以保证ML实体的正常通信。
基于图10所示的技术方案，当ML实体在第一链路上发送PPDU时，ML实体在第二链路上发送MAC帧，以使得第二链路上同一BSS内的其他站点在第一时段的结束时刻之前不会发送PPDU。这样一来，保证该ML实体不会发生在第一链路上发送PPDU，在第二链路上接收PPDU的情况，从而保证ML实体的正常通信。
结合图14进行举例说明，ML AP实体在第一链路上向ML non-AP实体1发送PPDU，同时，ML AP实体在第二链路上发送MAC帧，以使得第二链路上的同一BSS内的non-AP STA不会向ML AP发送PPDU。从而，ML AP实体不会发生在第一链路上发送PPDU，在第二链路上接收PPDU的情况，保证ML AP实体的正常通信。
如图15所示，为本申请实施例提供的一种通信保护方法，该方法包括以下步骤：
S301、ML实体在第一链路上侦听到PPDU的开始。
其中，ML实体可以支持多个链路。第一链路可以是ML实体所支持的多个链路中的 任意一个链路。
可选的，PPDU的开始可以是指PPDU的L-STF。L-STF用于使站点同步接收PPDU。
作为一种实现方式，ML实体的第一链路的站点在第一链路上侦听到PPDU的开始。
S302、ML实体在第二链路上暂停第一退避计数器的计数。
其中，第二链路是ML实体所支持的多个链路中除了第一链路之外的其他链路。也即，第一链路和第二链路是不同的两个链路。
作为一种实现方式，当ML实体的第二链路的站点获知ML实体的第一链路的站点侦听到PPDU的开始时，ML实体的第二链路的站点暂停第一退避计数器的计数。从而，ML实体在第二链路上的退避流程被挂起。
可以理解的是，在第一退避计数器暂停计数之后，第一退避计数器的计数值保持为当前值。
S303、ML实体判断所述PPDU是intra-BSS PPDU还是inter-BSS PPDU。
作为一种实现方式，ML实体的第一链路的站点判断所述PPDU是intra-BSS PPDU还是inter-BSS PPDU。所述PPDU是intra-BSS PPDU还是inter-BSS PPDU的判断方法可以参考现有技术，在此不再赘述。
在所述PPDU是intra-BSS PPDU的情况下，ML实体执行下述步骤S304。
在所述PPDU是inter-BSS PPDU的情况下，ML实体执行下述步骤S305。
S304、在所述PPDU是intra-BSS PPDU的情况下，所述ML实体在所述PPDU传输完毕之后，在第二链路上继续回退。
作为一种实现方式，若所述PPDU是intar-BSS PPDU，则在所述PPDU传输完毕之后，所述ML实体的第二链路的站点恢复第一退避计数器的计数功能。从而，ML实体的第二链路的站点可以继续执行退避流程。
在本申请实施例中，所述ML实体在所述PPDU传输完毕之后，继续回退，包括以下情形之一：
情形一、所述ML实体在第一时刻之后继续回退。第一时刻即为所述PPDU传输结束时刻。
作为一种实现方式，在第一时刻之后，ML实体等待第二链路的空闲时间达到第二帧间间隔。在第二链路的空闲时间达到第二帧间间隔之后，每当第二链路在一个时隙内处于空闲状态，则第二链路的第一退避计数器的计数值减1，直至第二链路的第一退避计数器的计数值为0。
结合图16(a)进行举例说明，ML实体1在第一链路上发送PPDU#1。当ML实体2在第一链路上侦听到该PPDU#1的开始时，ML实体2在第二链路上暂停第一退避计数器的计数，此时，第一退避计数器的计数值为5。之后，ML实体2在第二链路上侦听完PPDU#1的物理包头之后，基于物理包头中的信息，ML实体2确定该PPDU#1是intra-BSS PPDU。从而，在PPDU#1传输结束时刻，ML实体2在第二链路上恢复第一退避计数器的计数功能，继续回退。具体的，ML实体2等待第二链路的空闲时间达到第二帧间间隔。在第二链路的空闲时间达到第二帧间间隔之后，第二链路的第一退避计数器从5开始回退。在退避计数器的计数值减为0时，ML实体2在第二链路上发送PPDU#2。
情形二、所述ML实体在第二时刻之后继续回退。第二时刻即为所述PPDU对应的响 应帧的传输结束时刻。
作为一种实现方式，在第一时刻之后，ML实体等待第二链路的空闲时间达到第二帧间间隔。在第二链路的空闲时间达到第二帧间间隔之后，每当第二链路在一个时隙内处于空闲状态，则第二链路的第一退避计数器的计数值减1，直至第二链路的第一退避计数器的计数值为0。
可选的，所述第二时刻可以根据所述PPDU传输结束时刻、第一帧间间隔、以及BA帧的最大传输时长来确定。示例性的，第一帧间间隔可以为SIFS，本申请实施例不限于此。
结合图16(b)进行举例说明，ML实体1在第一链路上发送PPDU#1。当ML实体2在第一链路上侦听到该PPDU#1的开始时，ML实体2在第二链路上暂停第一退避计数器的计数，此时，第一退避计数器的计数值为5。之后，ML实体2在第二链路上侦听完PPDU#1的物理包头之后，基于物理包头中的信息，ML实体2确定该PPDU#1是intra-BSS PPDU。从而，在PPDU#1传输完毕之后，ML实体2根据PPDU#1传输结束时刻、第一帧间间隔、以及响应帧的最大传输时长，确定第二时刻。当时间达到第二时刻时，ML实体2在第二链路上恢复第一退避计数器的计数功能，继续回退。具体的，ML实体2等待第二链路的空闲时间达到第二帧间间隔。在第二链路的空闲时间达到第二帧间间隔之后，第二链路的第一退避计数器从5开始回退。在第一退避计数器的计数值减为0时，ML实体2在第二链路上发送PPDU#2。
情形三、所述ML实体在第三时刻之后继续回退。第三时刻即为所述PPDU的持续时间字段所确定的结束时刻。具体的，第三时刻与所述PPDU传输结束时刻之间的时间间隔等于所述PPDU的持续时间字段的取值。
作为一种实现方式，在第一时刻之后，ML实体等待第二链路的空闲时间达到第二帧间间隔。在第二链路的空闲时间达到第二帧间间隔之后，每当第二链路在一个时隙内处于空闲状态，则第二链路的第一退避计数器的计数值减1，直至第二链路的第一退避计数器的计数值为0。
结合图16(c)进行举例说明，ML实体1在第一链路上发送PPDU#1。当ML实体2在第一链路上侦听到该PPDU#1的开始时，ML实体2在第二链路上暂停第一退避计数器的计数，此时，第一退避计数器的计数值为5。之后，ML实体2在第二链路上侦听完PPDU#1的物理包头之后，基于物理包头中的信息，ML实体2确定该PPDU#1是intra-BSS PPDU。从而，在PPDU#1传输完毕之后，ML实体2根据PPDU#1传输结束时刻以及PPDU#1的持续时间字段的取值，确定第三时刻。当时间达到第三时刻时，ML实体2在第二链路上恢复第一退避计数器的计数功能，继续回退。具体的，ML实体2等待第二链路的空闲时间达到第二帧间间隔。在第二链路的空闲时间达到第二帧间间隔之后，第二链路的第一退避计数器从5开始回退。在第一退避计数器的计数值减为0时，ML实体2在第二链路上发送PPDU#2。
S305、在所述PPDU是inter-BSS PPDU的情况下，所述ML实体在第二链路上继续回退。
作为一种实现方式，若所述PPDU是inter-BSS PPDU，则所述ML实体的第二链路的站点恢复第一退避计数器的计数功能。从而，ML实体的第二链路的站点可以继续执行退避流程。
可选的，在第四时刻之后，每当第二链路在一个时隙内处于空闲状态，则第二链路的第一退避计数器的计数值减1，直至第二链路的第一退避计数器的计数值为0。
或者，在第四时刻之后，ML实体等待第二链路的空闲时间达到第二帧间间隔。在第二链路的空闲时间达到第二帧间间隔之后，每当第二链路在一个时隙内处于空闲状态，则第二链路的第一退避计数器的计数值减1，直至第二链路的第一退避计数器的计数值为0。
上述第四时刻是ML实体确定所述PPDU是inter-BSS PPDU的时刻。
结合图16(d)进行举例说明，ML实体1在第一链路上发送PPDU#1。当ML实体2在第一链路上侦听到该PPDU#1的开始时，ML实体2在第二链路上暂停第一退避计数器的计数，此时，第一退避计数器的计数值为5。之后，ML实体2在第二链路上侦听完PPDU#1的物理包头之后，ML实体2确定该PPDU#1是inter-BSS PPDU。这种情况下，ML实体2立即在第二链路上恢复第一退避计数器的计数功能，继续回退。在回退结束之后，ML实体2在第二链路上发送PPDU#2。
基于图15所示的技术方案，ML实体在第一链路上侦听到PPDU的开始后，ML实体在第二链路上暂停第一退避计数器的计数。在PPDU是intra-BSS PPDU的情况下，ML实体在该PPDU传输完毕之后，才继续回退。从而，在第一链路上的PPDU传输过程中，ML实体不会在第二链路上发送PPDU，避免导致同一BSS内的其他ML实体发生在第一个链路上接收信号，在另一个链路上发送信号的情况。另外，当ML实体确定该PPDU是inter-BSS PPDU时，ML实体立即继续回退，从而保证了ML实体能够正常在第二链路上进行信道接入。
作为一个可选的实施例，基于图15所示的技术方案，如图17所示，该通信保护方法在步骤S302之后还包括步骤S306-S307。并且，步骤S305可以替换为步骤S305a-S305b。
S306、ML实体在第二链路上配置第二退避计数器。
作为一种实现方式，ML实体的第二链路的站点配置第二退避计数器，第二退避计数器的初始值为第一退避计数器的当前值。
举例来说，假设在ML实体在冻结第一退避计数器时，第一退避计数器的当前值为15，则第二退避计数器的初始值也为15。
S307、ML实体基于第二退避计数器，进行虚拟回退。
其中，虚拟回退是指：若所述第二链路在当前时刻处于空闲状态，则每当所述第二链路在一个时隙内处于空闲状态，则所述ML实体将第二退避计数器的计数值减1。若所述第二链路在当前时刻处于繁忙状态，则所述ML实体等待所述第二链路的空闲时间达到第二帧间间隔；在所述第二链路的空闲时间达到第二帧间间隔之后，每当所述第二链路在一个时隙内处于空闲状态，则所述ML实体将第二退避计数器的计数值减1。
应理解，上述当前时刻是指ML实体配置完第二退避计数器的时刻。
可选的，上述第二帧间间隔可以为AIFS，或者其他帧间间隔，本申请实施例不限于此。
可以理解的是，若第二链路在某一个时隙处于繁忙状态，则ML实体需要重新等待第二链路的空闲时间达到第二帧间间隔。在第二链路的空闲时间达到第二帧间间隔之后，ML实体重新对第二退避计数器进行计数。
可选的，第二链路的忙闲状态可以根据第二链路的主信道的忙闲状态来确定。也即，若第二链路的主信道处于繁忙状态，则说明第二链路处于繁忙状态。若第二链路的主信道 处于空闲状态，则说明第二链路处于空闲状态。其中，第二链路的主信道可以是预先配置的，也可以是标准中定义的，本申请实施例不限于此。例如，第二链路的主信道可以是第二链路对应的频段中频率最高的20MHz信道。又例如，第二链路的主信道可以是第二链路对应的频段中频率最低的20MHz的信道。
在本申请实施例中，在ML实体判断出PPDU是intra-BSS PPDU还是inter-BSS PPDU之前，若第二退避计数器的计数值递减到0，ML实体可以采用以下方式中的任意一种来维护第二退避计数器。
方式一、ML实体保持第二退避计数器的计数值为0。
也就是说，ML实体的第二链路的站点保持第二退避计数器的计数值为0。
方式二、ML实体重新设置第二退避计数器的计数值。应理解，在第二退避计数器重新配置计数值之后，ML实体基于第二退避计数器，继续回退。
需要说明的是，ML实体重新设置第二退避计数器的计数值，包括：ML实体根据加倍后的竞争窗口，重新设置第二退避计数器的计数值。或者，ML实体根据竞争窗口的最小值，重新设置第二退避计数器的计数值。或者，ML实体根据竞争窗口，重新设置第二退避计数器的计数值。
上述加倍具体是指，如果竞争窗口CW没有达到CWmax，则将CW更新为2*CW+1；如果竞争窗口CW为CWmax，则将CW保持不变。
需要说明的是，步骤S306-S307与步骤S303是同时执行的。
S305a、在所述PPDU是inter-BSS PPDU的情况下，ML实体将第一退避计数器的计数值设置为第二退避计数器的计数值。
作为一种实现方式，ML实体的第二链路的站点将第一退避计数器的计数值设置为第二退避计数器的计数值。
举例来说，假设在ML实体在冻结第一退避计数器时，第一退避计数器的当前值为15。之后，在ML实体确定PPDU是inter-BSS PPDU的情况下，若第二退避计数器的计数值为10，则第一退避计数器的计数值更新为10。
S305b、ML实体基于第一退避计数器，在第二链路上继续回退。
作为一种实现方式，ML实体的第二链路的站点在第二链路上恢复第一退避计数器的计数功能，继续回退。
可选的，在第四时刻之后，每当第二链路在一个时隙内处于空闲状态，则第二链路的第一退避计数器的计数值减1，直至第二链路的第一退避计数器的计数值为0。上述第四时刻是ML实体确定所述PPDU是inter-BSS PPDU的时刻。
可选的，无论第二链路在第四时刻之前的第二帧间间隔内是否一直处于空闲状态，只要第二链路在第四时刻处于空闲状态，则每当第二链路在一个时隙内处于空闲状态，则第二链路的第一退避计数器的计数值减1，直至第二链路的第一退避计数器的计数值为0。
结合图16(e)对图17所示的技术方案进行举例说明。如图16(e)所示，ML实体1在第一链路上发送PPDU#1。当ML实体2在第一链路上侦听到该PPDU#1的开始时，ML实体2在第二链路上暂停第一退避计数器的计数，此时，第一退避计数器的计数值为5。同时，ML实体2在第二链路上配置第二退避计数器，第二退避计数器的计数值为5。
在ML实体2在第一链路上侦听PPDU#1的物理包头的两个时隙中，第二链路处于空 闲状态，因此第二退避计数器的计数值减为3。ML实体2在第二链路上侦听完PPDU#1的物理包头之后，ML实体2确定该PPDU#1是inter-BSS PPDU。这种情况下，ML实体2将第一退避计数器的计数值更新为3，并继续回退。在第一退避计数器的计数值减为0后，ML实体2在第二链路上发送PPDU#2。
结合图16(f)对图17所示的技术方案进行举例说明。如图16(f)所示，ML实体1在第一链路上发送PPDU#1。当ML实体2在第一链路上侦听到该PPDU#1的开始时，ML实体2在第二链路上暂停第一退避计数器的计数，此时，第一退避计数器的计数值为5。同时，ML实体2在第二链路上配置第二退避计数器，第二退避计数器的计数值为5。在ML实体2在第一链路上侦听PPDU#1的物理包头的两个时隙中，第二链路处于空闲状态，因此第二退避计数器的计数值减为3。ML实体2在第二链路上侦听完PPDU#1的物理包头之后，ML实体2确定该PPDU#1是intra-BSS PPDU。这种情况下，ML实体2不更新第一退避计数器的计数值，从而ML实体2基于计数值为5的第一退避计数器，继续回退。在第一退避计数器的计数值减为0后，ML实体2在第二链路上发送PPDU#2。
基于图17所示的技术方案，ML实体在第一链路上侦听到PPDU的开始后，ML实体在第二链路上暂停第一退避计数器的计数。同时，ML实体配置第二退避计数器，第二退避计数器的初始值为第一退避计数器的当前值。从而，ML实体基于第二退避计数器，进行虚拟回退。当ML实体确定PPDU是inter-PPDU时，ML实体再以第二退避计数器的计数值设置第一退避计数器的计数值，从而使得第一退避计数器不受之前暂停的影响。这样一来，在PPDU是inter-BSS PPDU的情况下，ML实体在第二链路上的退避流程是不受影响的，从而避免ML实体在信道竞争中处于劣势，保证ML实体对于第二链路的使用。
作为一种可选的实施例，基于图15所示的技术方案，如图18所示，该通信保护方法在步骤S302之后还包括步骤S308-S309。并且，步骤S305可以替换为步骤S305c-S305d。
S308、ML实体在第二链路上设置第三计数器。
其中，第三计数器用于记录第二链路的空闲时间。第三计数器的初始值可以为0。
S309、ML实体根据第二链路的空闲时间，更新第三计数器的计数值。
作为一种实现方式，每当第二链路在一个时隙内处于空闲状态，ML实体将第三计数器的计数值加1。
S305c、在所述PPDU是inter-BSS PPDU的情况下，ML实体根据第三计数器的计数值，设置第一退避计数器的计数值。
可选的，若第一退避计数器的当前值减去第三计数器的计数值大于等于0，则第一退避计数器的计数值等于第一退避计数器的当前值减去第三计数器的计数值。若第一退避计数器的当前值减去第三计数器的计数值小于0，则第一退避计数器的计数值为0。
例如，假设ML实体暂停第一退避计数器的计数时，第一退避计数器的当前值为10。若在ML实体判断PPDU是否是inter-BSS PPDU的过程中，第二链路的空闲时间达到9个时隙，则第三计数器的计数值为9。这样一来，在确定PPDU是inter-BSS PPDU时，ML实体可以将第一退避计数器的计数值设置为1。
又例如，假设ML实体暂停第一退避计数器的计数时，第一退避计数器的当前值为10。若在ML实体判断PPDU是否是inter-BSS PPDU的过程中，第二链路的空闲时间达到12个时隙，则第三计数器的计数值为12。这样一来，在确定PPDU是inter-BSS PPDU时， ML实体可以将第一退避计数器的计数值设置为0。
S305d、ML实体基于第一退避计数器，在第二链路上继续回退。
作为一种实现方式，ML实体的第二链路的站点在第二链路上恢复第一退避计数器的计数功能，继续回退。
可选的，在第四时刻之后，每当第二链路在一个时隙内处于空闲状态，则第二链路的第一退避计数器的计数值减1，直至第二链路的第一退避计数器的计数值为0。
上述第四时刻是ML实体确定所述PPDU是inter-BSS PPDU的时刻。
可选的，无论第二链路在第四时刻之前的第二帧间间隔内是否一直处于空闲状态，只要第二链路在第四时刻处于空闲状态，则每当第二链路在一个时隙内处于空闲状态，则第二链路的第一退避计数器的计数值减1，直至第二链路的第一退避计数器的计数值为0。
结合图16(g)对图18所示的技术方案进行举例说明。如图16(g)所示，ML实体1在第一链路上发送PPDU#1。当ML实体2在第一链路上侦听到该PPDU#1的开始时，ML实体2在第二链路上暂停第一退避计数器的计数，此时，第一退避计数器的计数值为5。同时，ML实体2在第二链路上配置第三计数器。在ML实体2在第一链路上侦听PPDU#1的物理包头的两个时隙中，第二链路处于空闲状态，因此第三计数器的计数值更新为2。ML实体2在第二链路上侦听完PPDU#1的物理包头之后，ML实体2确定该PPDU#1是inter-BSS PPDU。这种情况下，ML实体2根据第三退避计数器的计数值，将第一退避计数器的计数值更新为3。ML实体2基于计数值为3的第一退避计数器，继续回退。在第一退避计数器的计数值减为0后，ML实体2在第二链路上发送PPDU#2。
基于图18所示的技术方案，ML实体在第一链路上侦听到PPDU的开始后，ML实体在第二链路上暂停第一退避计数器的计数。同时，ML实体配置第三计数器，并以第三计数器记录第二链路的空闲时间。当ML实体确定PPDU是inter-PPDU时，ML实体根据第三计数器的计数器，更新第一退避计数器的计数值，从而使得第一退避计数器不受之前暂停的影响。这样一来，在PPDU是inter-BSS PPDU的情况下，ML实体在第二链路上的退避流程是不受影响的，从而避免ML实体在信道竞争中处于劣势，保证ML实体对于第二链路的使用。
如图19所示，为本申请实施例提供的一种通信保护方法，该方法包括以下步骤：
S401、ML non-AP实体在第一链路上侦听到第一PPDU。
其中，ML non-AP支持多个链路。第一链路是ML non-AP实体所支持的多个链路中的任意一个链路。
可选的，第一PPDU可以为单用户(single user，SU)PPDU、扩展范围(extended range，ER)SU PPDU、基于触发帧的(trigger based，TB)PPDU、或者上行多用户(multiple user，MU)PPDU中的任意一种。
作为一种实现方式，ML non-AP实体的第一链路的站点在第一链路上侦听到第一PPDU。
在侦听到第一PPDU之后，ML non-AP站点判断该第一PPDU的接收端是否是该ML non-AP实体所关联的ML AP实体。例如，若该第一PPDU的SIG字段中的BBS color与该ML non-BSS实体的第一链路的站点所属的BSS的BSS color相同，并且第一PPDU的SIG字段中的UL/DL参数用于指示该第一PPDU是上行传输的，则该第一PPDU的接收端 是该ML non-AP实体所关联的ML AP实体。
S402、若第一PPDU的接收端是所述ML non-AP实体所关联的ML AP实体，则所述ML non-AP实体在第二链路上发送第二PPDU。
其中，所述第二链路是所述ML non-AP所支持的多个链路中除了第一链路之外的其他链路。
在本申请实施例中，第二PPDU的结束时刻与第一PPDU的结束时刻相同，以保证ML non-AP实体所关联的ML AP实体在第一链路和第二链路上能够同时接收PPDU，以及同时发送BA帧。
为了保证第二PPDU的结束是可以与第一PPDU的结束时刻相同，因此ML non-AP实体可以根据第一PPDU的传输时长，确定第二PPDU的传输时长。具体的，ML non-AP实体根据第一PPDU的起始时刻，第一PPDU的传输时长，以及第二PPDU的起始时刻，确定第二PPDU的传输时长。其中，第一PPDU的起始时刻是ML non-AP实体在第一链路上侦听到第一PPDU的L-STF的时刻。第二PPDU的起始时刻由ML non-AP实体自身确定。第一PPDU的传输时长可以根据第一PPDU的L-SIG字段来确定。
示例性的，第一PPDU的L-SIG字段中包含RATE字段和LENGTH字段。RATE字段用于指示第一PPDU的传输速率。LENGTH字段用于指示第一PPDU的数据长度。基于RATE字段和LENGTH字段，可以计算出L-SIG字段的结束时刻是可以至第一PPDU的结束时刻之间的时长。其具体计算方式可以参考现有技术。
应理解，第一PPDU的传输时长包括：第一PPDU的开始时刻至第一PPDU的L-SIG字段的结束时刻之间的时长，以及L-SIG字段的结束时刻是可以至第一PPDU的结束时刻之间的时长。
应理解，基于第一PPDU的结束时刻与第二PPDU的结束时刻相同，ML non-AP实体可以根据第二PPDU的传输时长，可以确定第二PPDU的起始时刻，以及第二PPDU中RATE字段和LENGTH字段的取值。
作为一种实现方式，所述ML non-AP实体的第二链路的站点从第一链路的站点获知到第一PPDU的接收端是所述ML non-AP实体所关联的ML AP实体；之后，所述ML non-AP实体的第二链路的站点在第二链路上发送第二PPDU。
可选的，ML non-AP实体在第二链路上发送第二PPDU，还包括：Ml non-AP实体在第二链路上执行退避流程；在退避流程结束之后，ML non-AP实体在第二链路上发送第二PPDU。其中，上述退避流程可以参考现有技术，在此不再赘述。
结合图20进行举例说明，ML non-AP实体1在退避流程结束之后在第一链路上发送RTS帧，以建立TXOP。之后，ML non-AP实体1在第一链路上向ML AP实体发送PPDU#1。ML non-AP实体2侦听到PPDU#1。在ML non-AP实体2确定该PPDU#1是发送给ML non-AP实体2关联的ML AP实体之后，ML non-AP实体2在第二链路上发送PPDU#2。PPDU#2的结束时刻与PPDU#1的结束时刻相同。从而，ML AP实体在同一时刻可以在第一链路上发送PPDU#1的BA帧，在第二链路上发送PPDU#2的BA帧。
基于图19所示的技术方案，若ML non-AP实体在第一链路上侦听到第一PPDU，且第一PPDU是发送给ML non-AP实体所关联的ML AP实体的，则ML non-AP实体在第二链路上发送第二PPDU。由于第二PPDU的结束时刻与第一PPDU的结束时刻相同，从而 ML AP实体可以在同一时刻发送第二PPDU的BA帧和第一PPDU的BA帧。这样一来，一方面，避免了ML AP实体发生在一个链路上发送信号，在另一个链路上接收信号的情况。另一方面，ML non-AP实体在第二链路上发送第二PPDU，有利于提高第二链路的利用率。
上述主要从ML实体的角度对本申请实施例提供的方案进行了介绍。可以理解的是，ML实体为了实现上述功能，其包含了执行每一个功能相应的硬件结构和/或软件模块。本领域技术人员应该很容易意识到，结合本文中所公开的实施例描述的各示例的单元及算法步骤，本申请能够以硬件或硬件和计算机软件的结合形式来实现。某个功能究竟以硬件还是计算机软件驱动硬件的方式来执行，取决于技术方案的特定应用和设计约束条件。专业技术人员可以对每个特定的应用来使用不同方法来实现所描述的功能，但是这种实现不应认为超出本申请的范围。
本申请实施例可以根据上述方法示例对装置进行功能模块的划分，例如，可以对应每一个功能划分每一个功能模块，也可以将两个或两个以上的功能集成在一个处理模块中。上述集成的模块既可以采用硬件的形式实现，也可以采用软件功能模块的形式实现。需要说明的是，本申请实施例中对模块的划分是示意性的，仅仅为一种逻辑功能划分，实际实现时可以有另外的划分方式。下面以采用对应每一个功能划分每一个功能模块为例进行说明：
图21为本申请实施例提供的一种ML实体的结构示意图。如图21所示，该ML实体包括第一单元101和第二单元102。
方案一、
第一单元101，用于在第一链路上侦听到第一PPDU。第二单元102，用于若第一PPDU是intra-BSS PPDU，且第一PPDU的持续时间字段的取值大于第二链路的目标NAV的数值，则将第二链路的目标NAV的数值更新为第一PPDU的持续时间字段的取值，第二链路为ML实体所支持的多个链路中除了第一链路之外的任意一个链路。
一种可能的设计中，第二单元102，用于若第一PPDU是inter-BSS PPDU，则不更新第二链路的目标NAV的数值；或者，若第一PPDU是intra-BSS PPDU，且第一PPDU的持续时间字段的取值小于等于第二链路的目标NAV的数值，则不更新第二链路的目标NAV的数值。
一种可能的设计中，第一单元101，还用于在第一链路上侦听到CF-end帧。第二单元102，用于在CF-end帧是intra-BSS PPDU，且第二链路的目标NAV的数值是根据第一PPDU的持续时间字段的取值来更新的情况下，将第二链路的目标NAV的数值设置为0。
一种可能的设计中，第二单元102，用于在第一单元101在第一链路上在预设时长内未侦听到第二PPDU，且第二链路的目标NAV的数值是根据第一PPDU的持续时间字段的取值来更新的情况下，重新设置第二链路的目标NAV，第二PPDU和第一PPDU来自于同一个站点。
一种可能的设计中，第二单元102，具体用于设置第二链路的目标NAV的数值为0；或者，设置第二链路的目标NAV的数值为第一数值，第一数值所确定的结束时刻与第二数值所确定的结束时刻相同，第二数值是在目标NAV根据第一PPDU的持续时间字段的取值更新之前目标NAV的数值。
一种可能的设计中，预设时长＝(2×aSIFSTime)+(第一PPDU响应帧传输时长)+ aRxPHYStartDelay+(2×aSlotTime)。其中，aSIFSTime表示SIFS的时长，aRxPHYStartDelay表示预设延迟的时长，aSlotTime表示一个时隙的时长。
一种可能的设计中，第一PPDU中承载RTS帧，响应帧为CTS帧。
一种可能的设计中，若ML实体为ML non-AP实体，则目标NAV包括以下情形之一：(1)若ML non-AP实体在第二链路上配置有intra-BSS NAV和基本basic NAV，则目标NAV为intra-BSS NAV；(2)若ML non-AP实体在第二链路上配置有intra-BSS NAV、basic NAV、以及第一NAV，则目标NAV为第一NAV。
一种可能的设计中，若ML实体为ML AP实体，则目标NAV包括以下情形之一：(1)若ML AP实体在第二链路上配置有intra-BSS NAV和basic NAV，则目标NAV为intra-BSS NAV；(2)若ML AP实体在第二链路上仅配置有intra-BSS NAV、basic NAV和第一NAV，则目标NAV为第一NAV；(3)若ML AP实体在第二链路上配置有第一NAV和第二NAV，则目标NAV为第一NAV。
方案二、
第一单元101，用于在第一链路上发送第一PPDU，第一PPDU包括持续时间字段，第一PPDU所包括的持续时间字段用于指示第一时段的时长。第二单元102，用于在第二链路上发送MAC帧，MAC帧用于指示第二时段的时长，第一时段的结束时刻与第二时段的结束时刻相同，第二时段内第二链路上的intra-BSS站点禁止发送第二PPDU，第二链路是ML实体所支持的多个链路中除了第一链路之外的任意一个链路。
一种可能的设计中，MAC帧为公告帧或者QTP帧。
一种可能的设计中，公告帧的持续时间字段的取值等于第二时段的时长，公告帧的持续时间字段用于设置intra-BSS的站点所维护的NAV的数值，公告帧的持续时间字段不用于设置OBSS站点所维护的NAV的数值。
一种可能的设计中，公告帧包括持续时间字段以及时长字段，时长字段用于设置intra-BSS的站点所维护的NAV的数值，持续时间字段的取值为0，时长字段的取值等于第二时段的时长。
方案三、
第一单元101，用于在第一链路上侦听到PPDU的开始。第二单元102，用于在第二链路上停止第一退避计数器的计数，第二链路是ML实体所支持的多个链路中除了第一链路之外的任意一个链路。第一单元101，还用于判断PPDU是intra-BSS PPDU，还是inter-BSS PPDU。第二单元102，还用于在PPDU是intra-BSS PPDU的情况下，在PPDU传输完毕之后，在第二链路上继续回退；在PPDU是inter-BSS PPDU的情况下，在第二链路上继续回退。
一种可能的设计中，第二单元102，具体用于在第一时刻之后，在第二链路上继续回退，第一时刻为PPDU的传输结束时刻；或者，在第二时刻之后，在第二链路上继续回退，第二时刻为PPDU对应的响应帧的传输结束时刻；或者，在第三时刻之后，在第二链路上继续回退，第三时刻为PPDU的持续时间字段所确定的结束时刻。
一种可能的设计中，第二单元102，还用于在第二链路上配置第二退避计数器，第二退避计数器的初始值为第一退避计数器的当前值；若第二链路在当前时刻处于空闲状态，则每当第二链路在一个时隙内处于空闲状态，则将第二退避计数器的计数值减1；若第二 链路在当前时刻处于繁忙状态，则等待第二链路的空闲时间达到第二帧间间隔；在第二链路的空闲时间达到第二帧间间隔之后，每当第二链路在一个时隙内处于空闲状态，则将第二退避计数器的计数值减1。
一种可能的设计中，第二单元102，还用于在第二退避计数器的计数值减到0之后，保持第二退避计数器的计数值为0。
一种可能的设计中，第二单元102，还用于当第二退避计数器的计数值减到0时，重新设置第二退避计数器的计数值。
一种可能的设计中，第二单元102，还用于根据加倍后的竞争窗口，重新设置第二退避计数器的计数值；或者，ML实体根据竞争窗口，重新设置第二退避计数器的计数值；或者，ML实体根据竞争窗口的最小值，重新设置第二退避计数器的计数值。
一种可能的设计中，第二单元102，具体用于在PPDU是inter-BSS PPDU的情况下，以第二退避计数器的计数值更新第一退避计数器的计数值，并基于第一退避计数器，在第二链路上继续回退。
方案四、
第一单元101，用于在第一链路上侦听到第一PPDU。第二单元102，用于在第一PPDU的接收端是ML实体所关联的ML AP实体的情况下，在第二链路上发送第二PPDU，第二链路是ML non-AP实体所支持的多个链路中除了第一链路之外的任意一个链路，第一PPDU的结束时刻与第二PPDU的结束时刻相同。
一种可能的设计中，第二单元102，具体用于在第二链路上执行退避流程；在第二链路上的退避流程结束之后，ML non-AP实体在第二链路上发送第二PPDU。
上述本申请实施例提供的ML实体，可以有多种产品形态来实现，例如，所述ML实体可配置成通用处理系统；又例如，所述ML实体可以由一般性的总线体系结构来实现；又例如，所述ML实体可以由专用集成电路(application specific integrated circuit，ASIC)来实现等。下面提供本申请实施例所述的ML实体可能的几种产品形态，应当理解的是，以下的产品形态仅为举例，不对本申请实施例所述的ML实体的可能的产品形态进行限定。
图22是本申请实施例所述的ML实体可能的产品形态的结果图。
作为一种可能的产品形态，本申请实施例所述的ML实体可以为通信设备，所述通信设备包括处理器201和收发器202。可选的，所述通信设备还包括存储介质203。
其中，处理器201用于执行图6中的步骤S102、S103、S104、S105，图8中的步骤S107，图9中的步骤S108，图15中的步骤S302-S305，图17中的步骤S306、S307、S305a和S305b，图18中的步骤S308、S309、S305c和S305d。收发器202用于执行图6中的步骤S101，图8中的步骤S106，图10中的步骤S201和S202，图15中的步骤S301，图19中的步骤S401和S402。
作为另一种可能的产品形态，本申请实施例所述的ML实体也可以由通用处理器或者专用处理器来实现，也即俗称的芯片来实现。该芯片包括：处理电路201和收发管脚202。可选的，该芯片还可以包括存储介质203。
其中，处理电路201用于执行图6中的步骤S102、S103、S104、S105，图8中的步骤S107，图9中的步骤S108，图15中的步骤S302-S305，图17中的步骤S306、S307、S305a和S305b，图18中的步骤S308、S309、S305c和S305d。收发管脚202用于执行图6中的 步骤S101，图8中的步骤S106，图10中的步骤S201和S202，图15中的步骤S301，图19中的步骤S401和S402。
本申请实施例还提供一种计算机可读存储介质，所述计算机可读存储介质中存储有计算机指令；当所述计算机可读存储介质在ML实体上运行时，使得该ML实体执行如图6、图8、图9、图10、图15、图17、图18、或者图19所示的方法。所述计算机指令可以存储在计算机可读存储介质中，或者从一个计算机可读存储介质向另一个计算机可读存储介质传输，例如，所述计算机指令可以从一个网站站点、计算机、服务器或者数据中心通过有线(例如同轴电缆、光纤、数字用户线(digital subscriber line，DSL))或无线(例如红外、无线、微波等)方式向另一个网站站点、计算机、服务器或数据中心进行传输。所述计算机可读存储介质可以是计算机能够存取的任何可用介质或者是包含一个或多个可以用介质集成的服务器、数据中心等数据存储设备。所述可用介质可以是磁性介质(例如，软盘、硬盘、磁带)，光介质、或者半导体介质(例如固态硬盘(solid state disk，SSD))等。
本申请实施例还提供一种包含计算机指令的计算机程序产品，当其在ML实体上运行时，使得ML实体可以执行图6、图8、图9、图10、图15、图17、图18、或者图19所示的方法。
尽管在此结合各实施例对本申请进行了描述，然而，在实施所要求保护的本申请过程中，本领域技术人员通过查看所述附图、公开内容、以及所附权利要求书，可理解并实现所述公开实施例的其他变化。在权利要求中，“包括”(comprising)一词不排除其他组成部分或步骤，“一”或“一个”不排除多个的情况。单个处理器或其他单元可以实现权利要求中列举的若干项功能。相互不同的从属权利要求中记载了某些措施，但这并不表示这些措施不能组合起来产生良好的效果。
尽管结合具体特征及其实施例对本申请进行了描述，显而易见的，在不脱离本申请的精神和范围的情况下，可对其进行各种修改和组合。相应地，本说明书和附图仅仅是所附权利要求所界定的本申请的示例性说明，且视为已覆盖本申请范围内的任意和所有修改、变化、组合或等同物。显然，本领域的技术人员可以对本申请进行各种改动和变型而不脱离本申请的精神和范围。这样，倘若本申请的这些修改和变型属于本申请权利要求及其等同技术的范围之内，则本申请也意图包含这些改动和变型在内。

Claims (26)

  1. 一种通信保护方法，其特征在于，所述方法应用于多链路ML实体，所述ML实体支持多个链路，所述方法包括：
    ML实体在第一链路上侦听到第一物理层协议数据单元PPDU；
    若所述第一PPDU是基本服务集内intra-BSS PPDU，且所述第一PPDU的持续时间字段的取值大于第二链路的目标网络分配向量NAV的数值，则所述ML实体将所述第二链路的目标NAV的数值更新为所述第一PPDU的持续时间字段的取值，所述第二链路为所述ML实体所支持的多个链路中除了所述第一链路之外的任意一个链路。
  2. 根据权利要求1所述的通信保护方法，其特征在于，所述方法还包括：
    若所述第一PPDU是基本服务集间inter-BSS PPDU，则所述ML实体不更新所述第二链路的目标NAV的数值；或者，
    若所述第一PPDU是intra-BSS PPDU，且所述第一PPDU的持续时间字段的取值小于等于第二链路的目标NAV的数值，则所述ML实体不更新所述第二链路的目标NAV的数值。
  3. 根据权利要求1所述的通信保护方法，其特征在于，所述方法还包括：
    所述ML实体在所述第一链路上侦听到无竞争结束CF-end帧；
    若所述CF-end帧是intra-BSS PPDU，且所述第二链路的目标NAV的数值是根据所述第一PPDU的持续时间字段的取值来更新的，则所述ML实体将所述第二链路的目标NAV的数值设置为0。
  4. 根据权利要求1所述的通信保护方法，其特征在于，所述方法还包括：
    若所述ML实体在第一链路上在预设时长内未侦听到第二PPDU，且所述第二链路的目标NAV的数值是根据所述第一PPDU的持续时间字段的取值来更新的，则所述ML实体重新设置所述第二链路的目标NAV，所述第二PPDU和所述第一PPDU来自于同一个站点。
  5. 根据权利要求4所述的通信保护方法，其特征在于，所述ML实体重新设置所述第二链路的目标NAV，包括：
    所述ML实体设置所述第二链路的目标NAV的数值为0；或者，
    所述ML实体设置所述第二链路的目标NAV的数值为第一数值，所述第一数值所确定的结束时刻与第二数值所确定的结束时刻相同，所述第二数值是在所述目标NAV根据所述第一PPDU的持续时间字段的取值更新之前所述目标NAV的数值。
  6. 根据权利要求4或5所述的通信保护方法，其特征在于，预设时长＝(2×aSIFSTime)+(第一PPDU响应帧传输时长)+aRxPHYStartDelay+(2×aSlotTime)；
    其中，aSIFSTime表示短帧间间隔SIFS的时长，aRxPHYStartDelay表示预设延迟的时长，aSlotTime表示一个时隙的时长。
  7. 根据权利要求6所述的通信保护方法，其特征在于，所述第一PPDU中承载请求发送RTS帧，所述响应帧为清除发送CTS帧。
  8. 根据权利要求1至7任一项所述的通信保护方法，其特征在于，若所述ML实体为ML非接入点non-AP实体，则所述目标NAV包括以下情形之一：
    若ML non-AP实体在第二链路上配置有intra-BSS NAV和基本basic NAV，则所述目 标NAV为intra-BSS NAV；
    若ML non-AP实体在第二链路上配置有intra-BSS NAV、basic NAV、以及第一NAV，则所述目标NAV为第一NAV。
  9. 根据权利要求1至7任一项所述的通信保护方法，其特征在于，若所述ML实体为ML接入点AP实体，则所述目标NAV包括以下情形之一：
    若ML AP实体在第二链路上配置有intra-BSS NAV和basic NAV，则所述目标NAV为intra-BSS NAV；
    若ML AP实体在第二链路上仅配置有intra-BSS NAV、basic NAV和第一NAV，则所述目标NAV为所述第一NAV；
    若ML AP实体在第二链路上配置有第一NAV和第二NAV，则所述目标NAV为第一NAV。
  10. 一种通信保护方法，其特征在于，所述方法应用于多链路ML实体，所述ML实体支持多个链路，所述方法包括：
    所述ML实体在第一链路上发送第一物理层协议数据单元PPDU，所述第一PPDU的持续时间字段用于指示第一时段的时长；
    所述ML实体在第二链路上发送媒体接入控制MAC帧，所述MAC帧用于指示第二时段的时长，所述第一时段的结束时刻与所述第二时段的结束时刻相同，所述第二时段内第二链路上的基本服务集内intra-BSS站点禁止发送第二PPDU，所述第二链路是所述ML实体所支持的多个链路中除了所述第一链路之外的任意一个链路。
  11. 根据权利要求10所述的通信保护方法，其特征在于，所述MAC帧为公告帧或者静默时间阶段QTP帧。
  12. 根据权利要求11所述的通信保护方法，其特征在于，所述公告帧的持续时间字段的取值等于所述第二时段的时长，所述公告帧的持续时间字段用于设置intra-BSS的站点所维护的网络分配向量NAV的数值，所述公告帧的持续时间字段不用于设置重叠基本服务集OBSS的站点所维护的NAV的数值。
  13. 根据权利要求11所述的通信保护方法，其特征在于，所述公告帧包括持续时间字段以及时长字段，所述时长字段用于设置intra-BSS的站点所维护的网络分配向量NAV的数值，所述持续时间字段的取值为0，所述时长字段的取值等于所述第二时段的时长。
  14. 一种通信保护方法，其特征在于，所述方法应用于多链路ML实体，所述ML实体支持多个链路，所述方法包括：
    所述ML实体在第一链路上侦听到物理层协议数据单元PPDU的开始；
    所述ML实体在第二链路上停止第一退避计数器的计数，所述第二链路是所述ML实体所支持的多个链路中除了所述第一链路之外的任意一个链路；
    所述ML实体判断所述PPDU是基本服务集内intra-BSS PPDU，还是基本服务集间inter-BSS PPDU；
    若所述PPDU是intra-BSS PPDU，则所述ML实体在所述PPDU传输完毕之后，在第二链路上继续回退；
    若所述PPDU是inter-BSS PPDU，则所述ML实体在第二链路上继续回退。
  15. 根据权利要求14所述的通信保护方法，其特征在于，所述ML实体在所述PPDU 传输完毕之后，在第二链路上继续回退，包括：
    所述ML实体在第一时刻之后，在第二链路上继续回退，所述第一时刻为所述PPDU的传输结束时刻；或者，
    所述ML实体在第二时刻之后，在第二链路上继续回退，所述第二时刻为所述PPDU对应的响应帧的传输结束时刻；或者，
    所述ML实体在第三时刻之后，在第二链路上继续回退，所述第三时刻为所述PPDU的持续时间字段所确定的结束时刻。
  16. 根据权利要求14或15所述的通信保护方法，其特征在于，在所述ML实体在第二链路上停止第一退避计数器的计数之后，所述方法还包括：
    所述ML实体在所述第二链路上配置第二退避计数器，所述第二退避计数器的初始值为所述第一退避计数器的当前值；
    若所述第二链路在当前时刻处于空闲状态，则每当所述第二链路在一个时隙内处于空闲状态，则所述ML实体将第二退避计数器的计数值减1；
    若所述第二链路在当前时刻处于繁忙状态，则所述ML实体等待所述第二链路的空闲时间达到第二帧间间隔；在所述第二链路的空闲时间达到第二帧间间隔之后，每当所述第二链路在一个时隙内处于空闲状态，则所述ML实体将第二退避计数器的计数值减1。
  17. 根据权利要求16所述的通信保护方法，其特征在于，所述方法还包括：
    在所述第二退避计数器的计数值减到0之后，所述ML实体保持所述第二退避计数器的计数值为0。
  18. 根据权利要求16所述的通信保护方法，其特征在于，所述方法还包括：
    当所述第二退避计数器的计数值减到0时，所述ML实体重新设置所述第二退避计数器的计数值。
  19. 根据权利要求18所述的通信保护方法，其特征在于，所述ML实体重新设置所述第二退避计数器的计数值，包括：
    所述ML实体根据加倍后的竞争窗口，重新设置所述第二退避计数器的计数值；或者，
    所述ML实体根据所述竞争窗口，重新设置所述第二退避计数器的计数值；或者，
    所述ML实体根据所述竞争窗口的最小值，重新设置所述第二退避计数器的计数值。
  20. 根据权利要求16至19任一项所述的通信保护方法，其特征在于，若所述PPDU是inter-BSS PPDU，则所述ML实体在第二链路上继续回退，包括：
    若所述PPDU是inter-BSS PPDU，则所述ML实体以所述第二退避计数器的计数值更新所述第一退避计数器的计数值，并基于所述第一退避计数器，在第二链路上继续回退。
  21. 一种通信保护方法，其特征在于，所述方法应用于多链路ML非接入点non-AP实体，所述ML non-AP实体支持多个链路，所述方法包括：
    所述ML non-AP实体在第一链路上侦听到第一物理层协议数据单元PPDU；
    若所述第一PPDU的接收端是所述ML non-AP实体所关联的ML接入点AP实体，则所述ML non-AP实体在第二链路上发送第二PPDU，所述第二链路是所述ML non-AP实体所支持的多个链路中除了所述第一链路之外的任意一个链路，所述第一PPDU的结束时刻与所述第二PPDU的结束时刻相同。
  22. 根据权利要求21所述的通信保护方法，其特征在于，所述ML non-AP实体在第 二链路上发送第二PPDU，包括：
    所述ML non-AP实体在所述第二链路上执行退避流程；
    在所述第二链路上的退避流程结束之后，所述ML non-AP实体在所述第二链路上发送所述第二PPDU。
  23. 一种多链路ML实体，其特征在于，所述ML实体包括用于执行权利要求1至22任一项所涉及的方法中各个步骤的单元。
  24. 一种计算机可读存储介质，其特征在于，所述计算机可读存储介质包括计算机指令，当所述计算机指令在计算机上运行时，使得计算机执行如权利要求1至22任一项所述的通信保护方法。
  25. 一种计算机程序产品，其特征在于，所述计算机程序产品包括计算机指令，当所述计算机指令在计算机上运行时，使得计算机执行如权利要求1至22任一项所述的通信保护方法。
  26. 一种芯片，其特征在于，所述芯片支持多个链路，所述芯片包括处理电路和收发管脚；
    所述收发管脚，用于在第一链路上侦听到第一物理层协议数据单元PPDU；
    所述处理电路，用于在所述第一PPDU是基本服务集内intra-BSS PPDU，且所述第一PPDU的持续时间字段的取值大于第二链路的目标网络分配向量NAV的数值的情况下，将所述第二链路的目标NAV的数值更新为所述第一PPDU的持续时间字段的取值，所述第二链路为所述ML实体所支持的多个链路中除了所述第一链路之外的任意一个链路。
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11357025B2 (en) * 2019-09-10 2022-06-07 Samsung Electronics Co., Ltd. Multi link TXOP aggregation

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20220394756A1 (en) * 2019-11-06 2022-12-08 Lg Electronics Inc. Multi-link channel access
CN113141674A (zh) * 2021-04-08 2021-07-20 成都极米科技股份有限公司 多链路系统中链路配置方法、设备、系统及存储介质
CN117461383A (zh) * 2021-09-14 2024-01-26 Oppo广东移动通信有限公司 多链路通信方法、装置、设备及介质
WO2024019356A1 (ko) * 2022-07-18 2024-01-25 삼성전자 주식회사 복수의 링크의 지연 시간에 기반한 동작을 수행하는 전자 장치 및 전자 장치의 동작 방법
WO2024026581A1 (en) * 2022-07-30 2024-02-08 Huawei Technologies Co., Ltd. Multi-user edmg aggregate ppdu structure

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20130229995A1 (en) * 2012-03-01 2013-09-05 Futurewei Technologies, Inc. System and Methods for Differentiated Association Service Provisioning in WiFi Networks
CN106912108A (zh) * 2015-12-22 2017-06-30 华为技术有限公司 更新或者修改nav的方法及装置
CN107409430A (zh) * 2015-04-30 2017-11-28 英特尔Ip公司 多用户无线通信的装置、系统和方法
CN107926055A (zh) * 2015-08-20 2018-04-17 高通股份有限公司 用于空间重用的退避机制技术
CN109891998A (zh) * 2016-10-31 2019-06-14 索尼公司 通信设备和通信方法

Family Cites Families (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103416017B (zh) 2010-11-12 2016-11-16 交互数字专利控股公司 用于执行信道聚合和媒介访问控制重传的方法和设备
WO2016028032A1 (ko) 2014-08-18 2016-02-25 주식회사 윌러스표준기술연구소 데이터 동시 통신을 위한 무선 통신 방법 및 이를 이용한 무선 통신 단말
JP2016213568A (ja) 2015-04-30 2016-12-15 株式会社東芝 無線通信用集積回路
US10524231B2 (en) 2015-05-20 2019-12-31 Lg Electronics Inc. Method for managing NAV in wireless LAN system and device for same
KR102446836B1 (ko) * 2015-06-18 2022-09-23 엘지전자 주식회사 무선 랜 시스템에서 상향링크 송신을 수행하는 방법 및 장치
EP3313140B1 (en) * 2015-07-17 2023-11-01 Huawei Technologies Co., Ltd. Method for setting nav in wireless communication system, and related device
CN106912080B (zh) * 2015-12-22 2020-11-10 联芯科技有限公司 重选小区的方法、系统及所适用的移动终端
US11089628B2 (en) * 2016-04-22 2021-08-10 Lg Electronics Inc. Heterogeneous network allocation vector (NAV)-based communication in wireless LAN system
CN107659964A (zh) 2016-07-26 2018-02-02 中兴通讯股份有限公司 一种网络分配矢量的设置方法及装置
WO2018084034A1 (en) * 2016-11-04 2018-05-11 Panasonic Intellectual Property Corporation Of America Communication apparatus and communication method
US11979929B2 (en) * 2019-06-03 2024-05-07 Mediatek Singapore Pte. Ltd. Systems and methods for multi-link operation in a wireless network
US20210160958A1 (en) * 2019-11-22 2021-05-27 Qualcomm Incorporated Fragmentation and retransmission for multi-link operation in a wireless local area network (wlan)
US20210282186A1 (en) * 2020-03-04 2021-09-09 Qualcomm Incorporated Uplink (ul) aggregation for multi-link operation (mlo)
US11405944B2 (en) * 2020-06-24 2022-08-02 Sony Group Corporation Coordinated stations in OBSS with shared TXOP in the frequency domain

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20130229995A1 (en) * 2012-03-01 2013-09-05 Futurewei Technologies, Inc. System and Methods for Differentiated Association Service Provisioning in WiFi Networks
CN107409430A (zh) * 2015-04-30 2017-11-28 英特尔Ip公司 多用户无线通信的装置、系统和方法
CN107926055A (zh) * 2015-08-20 2018-04-17 高通股份有限公司 用于空间重用的退避机制技术
CN106912108A (zh) * 2015-12-22 2017-06-30 华为技术有限公司 更新或者修改nav的方法及装置
CN109891998A (zh) * 2016-10-31 2019-06-14 索尼公司 通信设备和通信方法

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP3982687A4

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11357025B2 (en) * 2019-09-10 2022-06-07 Samsung Electronics Co., Ltd. Multi link TXOP aggregation

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EP3982687A1 (en) 2022-04-13
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JP7255950B2 (ja) 2023-04-11
CN112188640A (zh) 2021-01-05
US11665264B2 (en) 2023-05-30
BR112021026902A2 (pt) 2022-05-10
US20220131956A1 (en) 2022-04-28

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