CN115529666A

CN115529666A - Channel access method, device, electronic equipment and readable storage medium

Info

Publication number: CN115529666A
Application number: CN202110713536.8A
Authority: CN
Inventors: 夏继康; 周明; 杨建华
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2021-06-25
Filing date: 2021-06-25
Publication date: 2022-12-27
Also published as: WO2022267747A1

Abstract

The embodiment of the application provides a channel access method, a device, an electronic device and a readable storage medium, wherein the method comprises the following steps: transmitting first data to a second node over a channel; responding to the existence of a first residual Network Allocation Vector (NAV) duration of a first node on a channel, and sending first NAV sharing information to a target node on the channel, wherein the first NAV sharing information indicates the target node to send data on the channel, the target node is a second node or a third node, a service channel of the third node is a channel accessed by the first node, and the third node is different from the second node. According to the method and the device, the target node can transmit data on the channel by using the residual NAV time length of the first node, the target node does not need to compete to access the channel, but directly transmits the second data on the channel in the residual NAV time length of the first node, the channel access capacity of the target node can be improved, the competition and the collision of the channel are reduced, the time delay of accessing the channel is reduced, and the throughput rate is improved.

Description

Channel access method, device, electronic equipment and readable storage medium

Technical Field

Embodiments of the present disclosure relate to communications technologies, and in particular, to a channel access method, a device, an electronic device, and a readable storage medium.

Background

With the popularization of Wi-Fi technology, more and more nodes contend for accessing a channel, the difficulty of accessing the channel by the nodes is increased, the probability of data transmission failure and collision is also increased, and long time delay is generated in interaction between the nodes.

Currently, in a Distributed Coordination Function (DCF) mode, only one node can access a channel at a time. Before accessing the channel, the node needs to monitor the channel state, and if the channel is idle, the node enters backoff. If the node is still idle at the end of the backoff, the node may transmit data on the channel. If the node fails to transmit data on the channel, the backoff duration of the node is increased, which causes unnecessary channel access delay. If the node transmits successful data on the channel, the node considers that the channel is idle, the backoff duration of the node is reduced, and the occurrence of contention conflict is easily caused.

In the current DCF mode, the difficulty of accessing a channel by a node is high, and the time delay is long.

Disclosure of Invention

The embodiment of the application provides a channel access method, a channel access device, an electronic device and a readable storage medium, which can reduce the difficulty of accessing a channel by a node and reduce time delay.

In a first aspect, an execution subject of the method may be a first node, or a chip or a processor in the first node, and the following description takes the execution subject as the first node as an example. The method comprises the following steps: the first node sends the first data to the second node on the channel, where the first node may be a node competing for accessing the channel, and the second node is an opposite node of the first node. When the transmission of the first data is completed, or the first node determines that the transmission of the first data is to be completed, it may be detected whether the first node has a first remaining network allocation vector NAV duration on the channel.

If the first node has a first remaining Network Allocation Vector (NAV) duration on the channel, the first node may send first NAV sharing information to a target node on the channel, where the first NAV sharing information indicates that the target node sends data on the channel. The target node is the second node or a third node, a traffic channel of the third node is the channel, and the third node is different from the second node. In other words, the third node is a node that requires contention for access to the channel where the first node is located, and the third node is a non-peer node of the first node.

In the embodiment of the application, the target node can utilize the remaining NAV duration of the first node to transmit data on the channel, so that the channel is prevented from being idle, the utilization rate of the channel can be improved, the target node does not need to compete for accessing the channel, but directly transmits data on the channel within the remaining NAV duration of the first node, the channel access capacity of the target node can be improved, the competition and collision of the channel are reduced, the time delay of accessing the channel is reduced, and the throughput rate is improved. In addition, since the NAV duration at the first node has not been reduced to 0, other nodes (nodes other than the first node and the second node) do not contend for access to the channel, and the success rate of the target node transmitting data within the first remaining NAV duration is high.

It should be appreciated that, in one embodiment, if the first node detects that the first node has the first NAV duration on the channel, the first node may detect whether the first NAV duration is available for the target node to transmit data. Wherein a first node may send the first NAV sharing information to the target node on the channel in response to the first node having a first remaining NAV duration on the channel, the first remaining NAV duration being greater than or equal to a first preset duration.

In the embodiment of the application, when detecting that the first remaining NAV duration is greater than or equal to the first preset duration, the first node sends the first NAV sharing information to the target node, so that the problem that the first node is large in power consumption and the first remaining NAV duration cannot be used by the target node due to the fact that the first node sends the first NAV sharing information when the first remaining NAV duration of the first node is short can be solved.

The following first explains a method for selecting a target node by a first node:

for one, in a possible implementation, the first node may determine, based on the priority of the node, whether to transmit the first NAV sharing information (i.e., share the first remaining NAV duration) to the second node or the third node. Wherein, the first node may take the node with the highest priority as the target node. Therefore, the method and the device can ensure that the node with high priority preferentially executes the service.

Secondly, in a possible implementation manner, the first node may determine, based on the first remaining NAV duration, to send the first NAV sharing information to the second node or the third node. In one embodiment, if the first remaining NAV duration is greater than or equal to the first preset duration and less than the second preset duration, the first node may regard the second node as the target node. If the first remaining NAV duration is greater than or equal to a second preset duration, the first node may use the third node as the target node, where the second preset duration is greater than the first preset duration. Therefore, in the embodiment of the present application, it can be ensured that the target node can smoothly execute the service of the target node on the basis of the first remaining NAV duration.

Next, a manner in which the first node determines the third node among the plurality of nodes that require to contend for access to the channel will be described:

for one, in a possible implementation, the first node may determine, based on the service priority, a third node sharing the first remaining NAV duration among a plurality of nodes that require contention for access to the channel. Wherein, the third node may be a node with the highest priority of the service. Therefore, the method and the device can ensure the smooth execution of the service with high priority.

In a possible implementation manner, the first node may determine, based on the duration of the unaccessed channel, a third node sharing the first remaining NAV duration among a plurality of nodes requiring contention for access to the channel. The first node may use the node with the largest duration of non-access to the channel as the third node. Therefore, the embodiment of the application can ensure that the node which does not access the channel for a long time accesses the channel to execute the service, and avoid the problem that the node which does not access the channel for a long time cannot execute the service all the time.

The manner in which the first node transmits the first NAV-sharing information to the target node will be described again. Wherein the first NAV sharing information comprises: the first remaining NAV duration, and/or an indication indicating that the first data transmission is complete. Illustratively, the indication that the first data transmission is complete may be an end flag.

For one, in a possible implementation, the first node may send a mutual aid channel access aid frame to the target node on the channel, where the aid frame includes the first NAV sharing information. For example, the first node may carry the first NAV sharing information in a Frame body field of the aid Frame. This approach is applicable to the target node being either the second node or the third node.

Secondly, in a possible implementation manner, when the target node is the second node, because the first node may send the first data to the second node, and the first data is composed of at least one data packet, the first node may carry the first NAV sharing information in a last data packet of the at least one data packet.

In one possible implementation, when the target node is the second node, the target node may feed back the second data to the first node in response to the first NAV sharing information from the first node. In one embodiment, in response to the second data, if it is detected that the first node has a second remaining NAV duration on the channel, and the second remaining NAV duration is greater than a first preset duration, the first node may send second NAV sharing information to the other node on the channel, where the second NAV sharing information indicates that the other node sends data on the channel. In other words, the first node may also share the second remaining NAV duration with other nodes to improve channel utilization.

In a possible implementation manner, when the target node does not have data to be sent, the target node may feed back first information to the first node, where the first information indicates that the target node does not have data to be sent. Accordingly, the first node may transmit second NAV-sharing information to the other nodes in response to the first information to instruct the other nodes to transmit data on the channel.

In a possible implementation manner, the first node may set a NAV duration on the channel when contending to access the channel, and the NAV duration of the first node is continuously decreased by counting down, so that when the NAV duration of the first node is decreased to 0, the first node may re-contend with the second node and the third node to access the channel.

In a second aspect, an embodiment of the present application provides a channel access method, where an execution subject of the method may be a target node, or a chip or a processor in the target node. The target node may be a second node or a third node, the second node is an opposite node of the first node, and the third node is a node which needs to compete for access to a channel where the first node is located. The method comprises the following steps: receiving, on a channel, first Network Allocation Vector (NAV) sharing information from a first node, where the first NAV sharing information indicates that a target node sends data on the channel, the target node is a second node or a third node, the second node is an opposite node of the first node, or a traffic channel of the third node is the channel and the third node is different from the second node.

In one possible implementation, the receiving, on a channel, first network allocation vector NAV sharing information from a first node includes: receiving a mutual aid channel access aid frame from the first node on the channel, wherein the aid frame comprises the first NAV sharing information.

In a possible implementation manner, if the target node is the second node, before the receiving the first network allocation vector NAV sharing information from the first node on the channel, the method further includes: receiving first data from the first node on the channel, the first data consisting of at least one data packet, the first NAV sharing information being carried in a last data packet of the at least one data packet.

In one possible implementation manner, the first NAV sharing information includes: a first remaining NAV duration of the first node, and/or an indication indicating completion of transmission of first data from the first node.

In a possible implementation manner, the third node is: and the node with the duration of the uncontended access channel being greater than or equal to the preset duration, or the node with the highest service priority.

In one possible implementation, after receiving the first network allocation vector NAV sharing information from the first node on the channel, the method further includes: and based on the first residual NAV duration of the first node, if the second data can be transmitted in the first residual NAV duration, the second data is sent to the opposite end node of the target node on the channel.

In this embodiment of the present application, the target node needs to estimate whether to complete transmission of the second data in the first remaining NAV duration based on the first remaining NAV duration, so that when the transmission of the second data can be completed in the first remaining NAV duration, the second data is sent to the peer node of the target node on the channel, and the transmission success rate of the second data can be ensured.

In a possible implementation manner, after the sending the second data to the peer node of the target node on the channel, the method further includes: and responding to the first node that a second residual NAV duration exists on the channel and the transmission of third data can be completed in the second residual NAV duration, and sending the third data to an opposite node of the target node on the channel.

In this embodiment, the target node may continuously transmit data to the peer node of the target node for multiple times based on the remaining NAV duration of the first node on the channel.

In one possible implementation, the second data is a minimum data unit that the target node supports sending.

In one possible implementation, after receiving the first network allocation vector NAV sharing information from the first node on the channel, the method further includes: and if it is determined that the transmission of the second data cannot be completed within the first remaining NAV duration based on the first remaining NAV duration of the first node, contending with the first node for accessing the channel when the NAV duration of the first node is reduced to 0, wherein the NAV duration of the first node is set when the first node accesses the channel.

In one possible implementation, after receiving the first network allocation vector NAV sharing information from the first node on the channel, the method further includes: and responding to the target node without the data to be sent, sending first information to the first node, wherein the first information indicates that the target node does not have the data to be sent.

In a possible implementation manner, after receiving the first network allocation vector NAV sharing information from the first node on the channel, the method further includes: and responding to the target node without the data to be sent, sending third NAV sharing information to other nodes, wherein the third NAV sharing information indicates the other nodes to send the data on the channel.

In this embodiment, the target node may share the remaining NAV duration of the first node with other nodes, so as to improve the channel utilization rate.

In a third aspect, an embodiment of the present application provides a channel access apparatus, including:

a transceiver module for: the method comprises the steps of sending first data to a second node on a channel, and responding to the fact that a first residual Network Allocation Vector (NAV) duration exists on the channel of the first node, sending first NAV sharing information to a target node on the channel, wherein the first NAV sharing information indicates the target node to send data on the channel, the target node is the second node or a third node, a traffic channel of the third node is the channel, and the third node is different from the second node.

In a possible implementation manner, the transceiver module is specifically configured to: and responding to the first node that a first residual NAV duration exists on the channel and the first residual NAV duration is larger than or equal to a first preset duration, and sending the first NAV sharing information to the target node on the channel.

In a possible implementation manner, when the first remaining NAV duration is greater than or equal to the first preset duration and is less than the second preset duration, the target node is the second node, and when the first remaining NAV duration is greater than or equal to the second preset duration, the target node is the third node, and the second preset duration is greater than the first preset duration.

In a possible implementation manner, the transceiver module is specifically configured to: and sending a mutual aid channel access aid frame to the target node on the channel, wherein the aid frame comprises the first NAV sharing information.

In one possible implementation, the first data is composed of at least one data packet, and the first NAV sharing information is carried in a last data packet of the at least one data packet.

In one possible implementation manner, the first NAV sharing information includes: the first remaining NAV duration, and/or an indication indicating that the first data transmission is complete.

In a possible implementation manner, the third node is: and the node with the duration of the uncompetitive access channel being greater than or equal to the preset duration or the node with the highest service priority.

In one possible implementation, the transceiver module is further configured to: when the target node is the second node, in response to receiving second data from the second node and the first node having a second remaining NAV duration on the channel, transmitting second NAV sharing information to other nodes on the channel, the second NAV sharing information indicating that the other nodes transmit data on the channel. Alternatively, the first and second electrodes may be,

and in response to receiving first information from the target node and the first node having a second remaining NAV duration on the channel, sending second NAV sharing information to other nodes on the channel, wherein the first information indicates that the target node does not have data to be sent.

In one possible implementation, the processing module is configured to: when a first node accesses a channel, setting the NAV duration of the first node, and when the NAV duration of the first node is reduced to 0, competing with the second node and the third node to access the channel.

In a fourth aspect, an embodiment of the present application provides a channel access apparatus, including:

a transceiver module for: receiving, on a channel, first Network Allocation Vector (NAV) sharing information from a first node, where the first NAV sharing information indicates that a target node sends data on the channel, and the target node is a second node or a third node, where the second node is an opposite node of the first node, or a traffic channel of the third node is the channel and the third node is different from the second node.

In a possible implementation manner, the transceiver module is specifically configured to: and receiving a mutual aid channel access aid frame from the first node on the channel, wherein the aid frame comprises the first NAV sharing information.

In a possible implementation manner, if the target node is the second node, the transceiver module is further configured to: receiving first data from the first node on the channel, the first data consisting of at least one data packet, the first NAV sharing information being carried in a last data packet of the at least one data packet.

In one possible implementation, the transceiver module is further configured to: and based on the first residual NAV duration of the first node, if the second data can be transmitted in the first residual NAV duration, the second data is sent to the opposite end node of the target node on the channel.

In one possible implementation, the transceiver module is further configured to: and responding to the first node that a second residual NAV duration exists on the channel and the transmission of third data can be completed in the second residual NAV duration, and sending the third data to an opposite node of the target node on the channel.

In one possible implementation, the processing module is configured to: and if it is determined that the transmission of the second data cannot be completed within the first remaining NAV duration based on the first remaining NAV duration of the first node, contending with the first node for accessing the channel when the NAV duration of the first node is reduced to 0, wherein the NAV duration of the first node is set when the first node accesses the channel.

In one possible implementation, the transceiver module is further configured to: and responding to the target node without the data to be sent, sending first information to the first node, wherein the first information indicates that the target node does not have the data to be sent.

In one possible implementation, the transceiver module is further configured to: and responding to the target node without the data to be sent, sending third NAV sharing information to other nodes, wherein the third NAV sharing information indicates the other nodes to send the data on the channel.

In a fifth aspect, an embodiment of the present application provides an electronic device, where the electronic device may be the first node, or may also be a chip in the first node, or the channel access apparatus of the third aspect. The electronic device may include: a processor, a memory.

The memory is for storing computer executable program code, the program code comprising instructions; the instructions, when executed by the processor, cause the electronic device to perform the method as in the first aspect.

In a sixth aspect, an embodiment of the present application provides an electronic device, where the electronic device may be a target node, or may also be a chip in the target node, or the channel access apparatus of the fourth aspect. The electronic device may include: a processor, a memory.

The memory is for storing computer executable program code, the program code comprising instructions; the instructions, when executed by the processor, cause the electronic device to perform the method as in the second aspect.

In a seventh aspect, embodiments of the present application provide a computer program product containing instructions, which when run on a computer, cause the computer to perform the method in the first to second aspects.

In an eighth aspect, embodiments of the present application provide a computer-readable storage medium having instructions stored therein, which when executed on a computer, cause the computer to perform the methods in the first to second aspects.

For each possible implementation manner of the second aspect to the eighth aspect, the beneficial effects thereof can be referred to the beneficial effects brought by the first aspect, and details are not repeated herein.

The embodiment of the application provides a channel access method, a device, an electronic device and a readable storage medium, a target node can transmit data on a channel by using the remaining NAV time of a first node, so that the channel is prevented from being idle, the utilization rate of the channel can be improved, the target node does not need to compete for accessing the channel, but directly sends second data on the channel within the remaining NAV time of the first node, the channel access capability of the target node can be improved, the competition and collision of the channel are reduced, the time delay of accessing the channel is reduced, and the throughput rate is improved. In addition, since the NAV duration at the first node has not been reduced to 0, other nodes (nodes other than the first node and the second node) do not contend for access to the channel, and the success rate of the target node transmitting data within the first remaining NAV duration is high.

Drawings

Fig. 1A is a schematic view of a scenario applicable to the embodiment of the present application;

FIG. 1B is a diagram illustrating a hidden terminal causing data collision in the prior art;

fig. 2A is a flowchart illustrating an embodiment of a channel access method according to an embodiment of the present application;

fig. 2B is a flowchart illustrating a channel access method according to another embodiment of the present application;

fig. 3 is a timing diagram illustrating sharing of remaining NAV duration according to an embodiment of the present disclosure;

fig. 4 is another timing diagram illustrating sharing of the remaining NAV duration according to an embodiment of the present disclosure;

fig. 5A is another timing diagram illustrating sharing of the remaining NAV duration according to an embodiment of the present disclosure;

fig. 5B is another timing diagram illustrating sharing of the remaining NAV duration according to an embodiment of the present disclosure;

FIG. 6 is a schematic diagram of another scenario in which the present embodiment is applied;

fig. 7A is a flowchart illustrating a channel access method according to another embodiment of the present application;

fig. 7B is a flowchart illustrating a channel access method according to another embodiment of the present application;

fig. 7C is a flowchart illustrating a channel access method according to another embodiment of the present application;

FIG. 8 is a schematic diagram of another scenario in which the present embodiment is applied;

fig. 9A is another timing diagram illustrating sharing of the remaining NAV duration according to an embodiment of the present disclosure;

fig. 9B is another timing diagram illustrating sharing of the remaining NAV duration according to an embodiment of the present disclosure;

fig. 10A is another timing diagram illustrating sharing of the remaining NAV duration according to an embodiment of the present application;

fig. 10B is another timing diagram illustrating sharing of the remaining NAV duration according to an embodiment of the present disclosure;

fig. 11 is a flowchart illustrating a channel access method according to another embodiment of the present application;

fig. 12 is a schematic structural diagram of a channel access apparatus according to an embodiment of the present application;

fig. 13 is a schematic structural diagram of a channel access apparatus according to an embodiment of the present application.

Detailed Description

In a Wireless Local Area Network (WLAN) of an IEEE802.11 protocol, two access channel mechanisms, namely, a Distributed Coordination Function (DCF) and a Point Coordination Function (PCF), are defined. DCF provides distributed access based on competition mechanism, multiple nodes compete for access channel, PCF provides central controlled polling access based on non-competition mechanism. It should be understood that the "DCF mode" described below characterizes the contention-based mechanism for accessing the channel between nodes.

Fig. 1A is a schematic view of a scene applicable to the embodiment of the present application. Referring to fig. 1A, the scenario includes at least two terminal devices, such as a mobile phone and a tablet, and fig. 1A illustrates an example where the mobile phone and the tablet operate in the same channel (for example, a 5G band 36 channel, or a Ch36 channel). When the mobile phone is successfully connected with the tablet personal computer, the mobile phone can be projected to the tablet personal computer. If the screen projection data are sent to the tablet personal computer by the mobile phone, the tablet personal computer displays the same picture as the mobile phone based on the screen projection data, and screen projection is achieved. In the process of projecting the screen of the mobile phone to the tablet personal computer, the mobile phone and the tablet personal computer can compete for accessing the channel so as to transmit data on the channel, and interaction between the mobile phone and the tablet personal computer is realized.

Illustratively, when the connection between the mobile phone and the tablet computer is successful, in the DCF mode, the mobile phone monitors the state of the 36 channels based on a carrier sense multiple access with collision avoidance (CSMA/CA) contention mechanism, and if the mobile phone determines that the 36 channels are idle within a preset duration, the mobile phone enters a backoff mode. The mobile phone entering back-off can be understood as: the mobile phone stores a backoff duration, and the mobile phone can begin to count down the backoff duration in response to detecting that 36 channels are idle within a preset duration. If the mobile phone monitors that the 36 channels are still idle when the backoff duration countdown is finished, the mobile phone can send screen projection data to the tablet computer on the 36 channels.

After receiving the screen-projected data from the mobile phone on the 36 channel, the tablet pc may contend to access the 36 channel, so as to feed back a transmission control protocol acknowledgement character (TCP ACK) to the mobile phone on the 36 channel. It should be understood that the TCP ACK referred to in the embodiment of the present application is a data frame, and is not a control frame, and the tablet computer needs to contend for an access channel to feed back the TCP ACK to the mobile phone. The process of the tablet computer competing for accessing the 36 channel may be as follows: the tablet computer monitors the state of the 36 channel based on a CSMA/CA competition mechanism, and if the tablet computer determines that the 36 channel is idle within a preset time length, the tablet computer enters a backoff mode. If the tablet computer monitors that the 36 channel is still idle when the back-off duration countdown of the tablet computer is finished, the tablet computer can feed back TCP ACK to the mobile phone on the 36 channel. Therefore, the mobile phone and the tablet computer complete one-time interaction.

It should be noted that, if the user operates on the tablet pc after the mobile phone is projected to the tablet pc, the tablet pc may send reverse touch data to the mobile phone based on the user operation, where the reverse touch data is used to indicate the mobile phone to perform a corresponding operation based on the user operation, and detailed description is not given here. The tablet computer sends the reverse touch data to the mobile phone, and also needs to contend for access to the 36 channel first to send the reverse touch data to the mobile phone on the 36 channel, which may refer to the description that the tablet computer feeds back TCP ACK to the mobile phone.

The manner of monitoring whether the 36 channels are idle by the mobile phone and the tablet pc may refer to the related description in the IEEE802.11 protocol, which is not described herein again.

Taking a mobile phone as an example, after the mobile phone contends to access the 36 channel, the mobile phone may send screen projection data to the tablet computer in the form of a data packet. The mobile phone may set a Network Allocation Vector (NAV) in a Duration field in a header of a MAC frame of the packet through Virtual Carrier Sensing (VCS). The NAV can be understood as a counter timer that characterizes the duration of time that the handset is still occupying the channel. The tablet may determine the NAV of the handset based on the Duration field in the header of the MAC frame, and the tablet may begin to count down the NAV of the handset in response to receiving a first packet from the handset that includes the NAV. The tablet considers the 36 channel busy without contending for access to the 36 channel until the NAV value of the handset decreases to 0, and the tablet begins contending for access to the 36 channel only when the NAV value of the handset decreases to 0. That is, the tablet computer receives screen projection data from the mobile phone on the 36 channel, and when the NAV value of the mobile phone is reduced to 0, the tablet computer can contend to access the 36 channel, so as to feed back TCP ACK or reverse touch data to the mobile phone on the 36 channel. It should be understood that the NAV duration and the NAV value in the following embodiments are synonymous with the NAV characterization, i.e., the NAV of the node.

Taking a mobile phone as an example, after the mobile phone contends to access a channel, if data transmission fails in a 36-channel, the mobile phone considers that the channel is congested, and in the current IEEE802.11 protocol, the mobile phone may double the backoff duration. However, the hidden terminal, channel error and other factors may also cause data transmission failure in 36 channels, and the backoff duration of the mobile phone is doubled, which may cause unnecessary channel access delay. If the mobile phone successfully transmits data in the 36 channels, the mobile phone considers that the channels are idle, and in the current IEEE802.11 protocol, the mobile phone may reduce the backoff duration, which may easily cause contention conflicts. The current method for the nodes to compete for accessing the channel has the disadvantages of high difficulty and long time delay for the nodes to access the channel. A node may be understood as a device, such as a cell phone or a tablet computer in fig. 1A, that contends for access to a channel.

For example, referring to fig. 1B, in an embodiment, the mobile phone is connected to the tablet computer, the smart screen is also connected to the tablet computer, and both the mobile phone and the smart screen can transmit data to and from the tablet computer. Assuming that the backoff duration of the mobile phone is 10ms and the backoff duration of the smart screen is 20ms, when the mobile phone is in competition to access a 36 channel, data can be sent to the tablet computer on the 36 channel, and if the smart screen is far away from the mobile phone and cannot monitor that the mobile phone is sending data to the tablet computer on the 36 channel, the 36 channel is considered to be idle, so that the smart screen is a hidden terminal relative to the mobile phone. Therefore, the smart screen also sends data to the tablet computer on 36 channels, which may cause data from the mobile phone and the smart screen to collide on 36 channels, resulting in data transmission failure of the mobile phone and the smart screen.

According to the current IEEE802.11 protocol, because data of the mobile phone and the smart screen are all failed to be sent on 36 channels, the mobile phone and the smart screen after data collision both double the Contention Window (CW), and the difficulty of the mobile phone and the smart screen competing for accessing the channel increases. Because the backoff duration is in a direct relationship with the contention window (for example, the backoff duration = rand (0,1) × CW, rand (0,1) represents any value between 0 and 1), the backoff durations of the mobile phone and the smart screen increase correspondingly with the increase of the contention window, and the backoff duration is described below as an example. Illustratively, the back-off duration of the mobile phone is adjusted to 20ms, and the back-off duration of the smart screen is adjusted to 40ms. Thus, when the mobile phone and the smart screen compete to access the 36 channel, the mobile phone can compete to access the 36 channel in preference to the smart screen because the backoff duration (or contention window) of the mobile phone is small. And the wisdom screen is for hiding the terminal for the cell-phone, leads to the data transmission of wisdom screen to fail always, and the competition window of wisdom screen increases until predetermineeing the maximum value, leads to the wisdom screen to be more difficult to compete and insert 36 channels. On the contrary, after the mobile phone competitively accesses the 36 channels and data transmission is successful, the competition window of the mobile phone can be reduced, the reduction of the competition window further enhances the capacity of the mobile phone competitively accessing the channels, the capacity of the mobile phone accessing the channels is strong, the channels can be always accessed at a large probability, and then the competition window can be continuously reduced until the preset minimum value is reached, so that other nodes are difficult to access the channels.

Because the nodes set NAVs of the nodes after contending to access the channel, the applicant finds that in order to ensure that the nodes can successfully transmit data, the nodes generally set NAVs longer than the duration required for transmitting data, so as to avoid data transmission failure caused by network jitter and transmission delay. Based on the problems of great difficulty and long time delay of the nodes accessing the channel in the current IEEE802.11 protocol, the applicant considers that the nodes competing for accessing the channel have the remaining NAV time length after the data is successfully transmitted on the channel, and other nodes do not need to compete for accessing the channel if the remaining NAV time length is shared with other nodes needing to compete for accessing the channel, so that the difficulty and the time delay of accessing the channel are reduced. Accordingly, the embodiments of the present application provide a channel access method, where after completing data transmission, a first node contending to access a channel may share the remaining NAV duration of the first node with other nodes, so that the other nodes may transmit data on the channel in the remaining NAV duration, which not only can improve the utilization rate of the channel, but also can reduce the difficulty and delay of accessing the channel.

In one embodiment, the nodes in the embodiment of the present application may include, but are not limited to: an Access Point (AP), a station (station) STA device or server, etc. The AP may be, but is not limited to: routers, customer Premise Equipment (CPE), etc. The STA device may be, but is not limited to: the mobile phone terminal comprises terminal equipment such as a mobile phone, a tablet computer, a notebook computer, wearable equipment and a sound box. Optionally, the STA device may also be a Personal Digital Assistant (PDA), a handheld device with wireless communication capability, a computing device, a Virtual Reality (VR) terminal device, an unmanned aerial vehicle device, an Augmented Reality (AR) terminal device, an intelligent device in home life, or the like. The node form in the embodiment of the present application is not limited.

The following describes a channel access method provided in the embodiments of the present application with reference to specific embodiments. The following several embodiments may be combined with each other and may not be described in detail in some embodiments for the same or similar concepts or processes.

Fig. 2A is a flowchart illustrating an embodiment of a channel access method according to an embodiment of the present application. Referring to fig. 2A, a channel access method provided in an embodiment of the present application may include:

s201, the first node sends first data to the second node on a channel.

The first node and the second node have established a connection, and the first node and the second node may be regarded as opposite end nodes with each other, such as the mobile phone and the smart screen in fig. 1A, where the mobile phone may be the first node and the smart screen may be the second node. In the embodiment of the present application, the first node has accessed the channel, and in an embodiment, the first node may contend for accessing the channel according to the DCF mode in the IEEE802.11 protocol. Alternatively, in one embodiment, the first node may access the channel based on the remaining NAV duration shared by other nodes, which may be described in relation to the following "the second node shares the first remaining NAV duration access channel". In the embodiments of the present application, a manner of accessing a channel by a first node is not limited, and the following embodiments take the first node as a contention access channel as an example for explanation.

Referring to fig. 3, a first node contends for access to a channel and may wait for a distributed inter-frame space (DIFS) before handshaking with a peer node (i.e., a second node) to avoid collision. For example, the first node may send a Request To Send (RTS) frame to the second node to characterize that the first node is about to send the first data to the second node. The second node, upon receiving the RTS frame, may feed back a Clear To Send (CTS) frame to the first node after a short inter-frame spacing (SIFS), informing the first node that the second node is ready to receive the first data. The first node receives the CTS frame and may send the first data to the second node over the channel one SIFS later. It should be understood that the following timing diagram is described with the third node as the other node contending for the channel.

Taking the example that the first node sends the screen projection data to the second node, the first node may split the screen projection data, encapsulate the split screen projection data in a plurality of data packets, and send the plurality of data packets to the second node on the channel in sequence. It should be understood that the channel described below is the same channel as the channel on which the first node sends the data packets.

After the first node contends for the access channel, the NAV duration of the first node may be set. For example, the first node may set a NAV duration of the first node based on a size of first data to be transmitted. For example, the first node needs to transmit 2 data packets in total, and the required time duration is 10ms, and in order to ensure that the data packets are successfully transmitted, the first node may set the NAV time duration to be 12ms. In one embodiment, the first node may set a NAV duration of the first node based on a size of the first data to be sent and a duration for the second node to feed back a TCP ACK. For example, the first node needs to send 2 data packets in total, the required time is 10ms, the second node needs to feed back two TCP ACKs, and the time is 2ms, so that the first node may set the NAV time to be 15ms in order to ensure that the data packets are sent successfully.

Illustratively, referring to fig. 3, after the first node sets the NAV duration of the first node, the NAV duration of the first node may be carried in an RTS frame, such as NAV (RTS) in the illustration. The value of the NAV continuously decreases with the passage of time, and when the second node feeds back a CTS frame to the first node, the NAV duration of the first node still remains NAV (CTS). It should be understood that, the first node also carries the remaining NAV duration of the first node in the header of the MAC frame of the data packet sent to the second node in the following, so that the second node can acquire the remaining NAV duration of the first node by parsing the data packet. It is conceivable that, because the NAV Duration of the first node is characterized by the Duration field in the header of the MAC frame, a third node in the same channel with the first node may also parse the MAC layer of the packet to obtain the remaining NAV Duration of the first node based on the packet from the first node.

S202, if the first node has the first remaining NAV duration on the channel, the first node sends NAV sharing information to the second node on the channel, where the NAV sharing information indicates that the second node sends data on the channel.

When the first node is about to complete the transmission of the first data or completes the transmission of the first data, if the first node has a first remaining NAV duration on the channel, the first node may transmit NAV sharing information to the second node on the channel, where the NAV sharing information indicates that the second node transmits data on the channel. In one embodiment, the first node may carry NAV sharing information in the last data packet sent to the second node. In one embodiment, the first node may send a mutual aid channel access (aid) frame to the second node after sending the last data packet to the second node, where the aid frame may include NAV sharing information. The following two ways of the first node transmitting NAV sharing information are described:

the first mode is as follows: the first node carries NAV sharing information in the last data packet sent to the second node. Fig. 3 shows that the first node transmits the last data packet to the second node, and the last data packet may carry NAV sharing information, and it should be understood that S202 in fig. 2A is described by taking as an example that the first node carries NAV sharing information in transmitting the last data packet to the second node. For example, referring to fig. 3, the first node may add an end flag in the reserve field of the data portion of the last packet, or add an end flag in the reserve field of the frame header portion of the last packet to indicate that the first node completes the first data transmission, and the second node may transmit data on the channel.

The second mode is as follows: the first node sends an aid frame to the second node. In this implementation, referring to fig. 4, the first node may send an aid frame to the second node on the channel after sending the last data packet to the second node and after an SIFS interval, where the aid frame includes NAV sharing information. In one embodiment, the NAV sharing information may include: the first remaining NAV duration of the first node and/or an indication, such as an end flag, indicating completion of transmission of the data packet.

In one embodiment, when the NAV sharing information may include: when the first remaining NAV duration of the first node and the flag, such as the end flag, indicating that the data packet transmission is completed are set, the second node may determine that the first data transmission of the first node is completed based on the end flag in the NAV sharing information, and may obtain the first remaining NAV duration of the first node on the channel based on the first remaining NAV duration in the NAV sharing information.

In one embodiment, when the NAV sharing information may include: when the first remaining NAV duration of the first node is long, the second node may not only acquire the first remaining NAV duration of the first node on the channel, but also determine that the second node may access the channel to transmit data on the channel based on the first remaining NAV duration.

In one embodiment, when the NAV sharing information may include: when the flag indicating completion of the transmission of the data packet, such as the end flag, is set, the second node may determine that the transmission of the first data by the first node is completed based on the end flag in the NAV sharing information. In addition, because the second node can acquire the NAV of the first node based on the data packet from the first node and count down the NAV, the second node can acquire the first remaining NAV duration of the first node when receiving the NAV sharing information, which can be referred to the above-mentioned description in S201.

In one embodiment, the format of the aid frame may be as shown in table one below:

watch 1

The aid Frame is a MAC Frame header except for a Frame body and a Frame Check Sequence (FCS). The Frame Control field may occupy a plurality of bits and is used for carrying information such as a protocol version and a Frame subtype. The Duration field may occupy multiple bits for carrying channel occupancy time information, such as NAV. Address1 (DA) denotes a destination Address, address2 (SA) denotes a source Address, and Address3 (BSSID) denotes a basic service set identifier. The Sequence Control field may occupy multiple bits for carrying Sequence number information of the packet. The Frame Body represents the payload, which may contain the first remaining NAV duration. The FCS is known as the frame end, i.e. the end field of a protocol data unit (frame) of a data link layer of a computer network, and is a segment of 2-byte cyclic redundancy check code.

In one embodiment, the first node may determine whether to transmit NAV sharing information to the second node based on the first remaining NAV duration. If the first remaining NAV duration is small and is not enough to complete transmission of any data, the first node may not transmit NAV sharing information to the second node, and if the first remaining NAV duration is greater than or equal to a first preset duration, the first node may transmit NAV sharing information to the second node.

S203, the second node responds to the NAV sharing information and judges whether the second node can finish the transmission of the second data within the first residual NAV duration; if so, go to S204, otherwise, go to S205.

Based on the above description in S201, the second node may obtain the remaining NAV duration of the first node, and accordingly, when the second node receives the NAV sharing information from the first node, it may be determined whether the transmission of the second data of the second node can be completed within the first remaining NAV duration.

For example, the first node sends a data packet for screen projection to the second node, where the second data may be TCP ACK, and the second node needs to feed back the TCP ACK to the first node, then the second node determines whether transmission of the TCP ACK can be completed within the first remaining NAV duration, that is, the second node determines whether the transmission duration of the TCP ACK is less than or equal to the first remaining NAV duration. And the second node determines that the transmission of the TCP ACK can be completed in the first residual NAV duration. And if the transmission time length of the TCP ACK is greater than the first residual NAV time length, the second node determines that the transmission of the TCP ACK cannot be completed within the first residual NAV time length.

In an embodiment, the second data may be understood as the smallest data unit that the second node supports to send, and the smallest data unit may be, for example, one packet into which the second data is split, or one fragment into which the second data is split. In such an embodiment, taking the minimum data unit as an example of a data packet, when the second node receives the NAV sharing information from the first node, it may be determined whether transmission of one data packet of the second data can be completed within the first remaining NAV duration. If the transmission of one data packet of the second data can be completed within the first remaining NAV duration, the second node may transmit one data packet of the second data on the channel.

In such an embodiment, the second node detects whether the transmission of one minimum data unit can be completed within the first remaining NAV duration, which may increase the utilization of the channel and complete the transmission of data within the limited remaining NAV duration. It should be understood that the transmission packets of the other data packets in the second data may be: after the second node competes for accessing the channel, the second node transmits the channel, or the second node transmits the channel by using the next NAV time shared by the first node, so that the residual NAV time of the first node can be effectively used, and the channel utilization rate is improved.

S204, the second node sends second data to the first node on the channel.

Illustratively, the second data may be a TCP ACK, and referring to fig. 3, the second node may feed back the TCP ACK to the first node on the channel after receiving the last data packet by one SIFS. Referring to fig. 4, the second node may feed back a TCP ACK to the first node on the channel after receiving an aid frame from the first node, spaced one SIFS apart.

In the current IEEE802.11 protocol, the second node may contend for accessing the channel in response to receiving the last data packet from the first node, so as to feed back the TCP ACK to the first node on the channel, and the difficulty of the second node contending for accessing the channel is large and the time is prolonged. In this embodiment, the second node may directly feed back the TCP ACK to the first node on the channel within the first remaining NAV duration. On one hand, the problem that the difficulty of accessing the channel is high and the time is prolonged is solved without competing for accessing the channel, on the other hand, because the NAV duration of the first node is not reduced to 0, other nodes (except the first node and the second node) cannot compete for accessing the channel, and the second node sends data in the first remaining NAV duration, the collision failure of data packets cannot be caused, and the success rate of data sending is high.

S205, when the NAV value of the first node decreases to 0, the first node and the second node compete to access the channel.

Because the second node cannot complete transmission of the second data within the first remaining NAV duration, the second node may not respond when receiving the NAV sharing information to count down the NAV of the first node, and further when the value of the NAV of the first node is reduced to 0, the first node and the second node may contend to access the channel via a DIFS. It should be understood that when the NAV value of the first node decreases to 0, the first node, the second node, and other nodes requiring access to the channel may contend to access the channel via a DIFS.

As above, the second node may transmit the second data on the channel for the NAV duration remaining at the first node. Therefore, in the scene that the mobile phone screens to the smart screen, after the mobile phone competitively accesses the channel, the longer NAV time can be set, so that after the mobile phone sends data to the smart screen, the smart screen can utilize the residual NAV time of the mobile phone to feed back TCP ACK (transmission control protocol ACK) to the mobile phone on the channel, the screen-throwing time delay is reduced, and the problem of blocking in screen throwing can be reduced.

It should be understood that the channel access method provided in the embodiment of the present application is not only applicable to a screen projection scenario, but also can be applied without limitation to: in a scenario of data transmission between an AP and an STA device, in a scenario of peer-to-peer (P2P) data transmission, in a scenario of Transmission Control Protocol (TCP) streaming, and in a scenario of two nodes located in the same island of a device-to-device (D2D) data transmission, and so on. It should be understood that the scenario of TCP streaming can be understood as: in a TCP communication scenario, a scenario of a TCP flow is transmitted between any two nodes. In an embodiment, D2D may be, but is not limited to, a traditional D2D scene, or a huawei device to device (HiD 2D) scene, and D2D is taken as the HiD2D as an example for explanation below.

In this embodiment, the first node may complete data transmission or be about to complete data transmission, and if the first node still has a remaining NAV duration on the channel, the first node may share the remaining NAV duration to the second node, so that the second node sends the second data to the first node on the channel by using the remaining NAV duration of the first node. In the embodiment of the application, the second node can transmit data on the channel by using the remaining NAV duration of the first node, so that the channel is prevented from being idle, the utilization rate of the channel can be improved, the second node does not need to compete for accessing the channel, but directly transmits the second data on the channel within the remaining NAV duration of the first node, the channel access capacity of the second node can be improved, the competition and collision of the channel are reduced, the time delay of accessing the channel is reduced, and the throughput rate is improved. In addition, since the NAV duration at the first node has not been reduced to 0, other nodes (nodes other than the first node and the second node) do not contend for access to the channel, and the success rate of the second node transmitting data within the first remaining NAV duration is high.

In an embodiment, after the first node receives the TCP ACK from the second node, if the first node detects that the first node still has the second remaining NAV duration on the channel, the first node may continue to share the second remaining NAV duration to other nodes, and the way of sharing to other nodes may refer to the following description of fig. 7A.

The method in this embodiment may be applicable to a scenario where a mobile phone simultaneously projects a screen to two devices, for example, the mobile phone may simultaneously project a screen to an intelligent screen and a tablet computer, referring to fig. 5A, taking an aid frame sent by the mobile phone to the intelligent screen as an example, the mobile phone may share the remaining NAV duration of the mobile phone to the intelligent screen, so that after the intelligent screen feeds back TCP ACK on a channel, the mobile phone may continue to send screen projection data to the tablet computer when detecting that the mobile phone still has a second remaining NAV duration on the channel, and send NAV sharing information to the tablet computer with the aid frame, so that the tablet computer feeds back TCP ACK to the mobile phone on the channel within the remaining NAV duration of the mobile phone. Therefore, the mobile phone can share the residual NAV duration to the two devices for use, and the screen-projecting time delay can be further reduced. It should be understood that the other nodes in fig. 5A and the following timing diagrams are: in addition to the first node and the second node, a node that requires access to a channel in which the first node is located.

In an embodiment, as in the above embodiment S204, after the second node feeds back the TCP ACK to the first node on the channel, if the second node further needs to send the reverse touch data to the first node, referring to fig. 2B, after S204, the method may further include:

s206, acquiring a second residual NAV time length of the first node, and judging whether the transmission of third data of the second node can be completed within the second residual NAV time length; if so, go to S207, otherwise, go back to S205.

The third data is different from the second data, for example, the second data is TCP ACK, and the third data is reverse touch data. For example, if the second node needs to send the reverse touch data to the first node after feeding back the TCP ACK to the first node, the second node may obtain a second remaining NAV duration of the first node after feeding back the TCP ACK to the first node, to determine whether transmission of the reverse touch data can be completed within the second remaining NAV duration, that is, the second node determines whether a duration of "duration of transmission of the reverse touch data" plus "one SIFS" is less than or equal to the first remaining NAV duration, which may refer to the above description of the TCP ACK.

In one embodiment, the third data may be understood as the smallest data unit, such as a data packet, that the third node supports to send, and reference may be made to the above description of the second data.

And S207, the second node sends third data to the first node on the channel.

For example, taking the first node sending an aid frame to the second node as an example, referring to fig. 5B, the second node may send the reverse touch data on the channel after sending a TCP ACK to the first node and after an interval of one SIFS. It should be understood that the second node may split the reverse touch data, encapsulate the split data into a plurality of data packets, and send the data packets to the first node, where the last data packet sent by the second node to the first node is shown in fig. 5B. In an embodiment, the reverse touch data may also be encapsulated in one data packet for transmission to the first node, where the data packet shown in fig. 5B is the one data packet.

In one embodiment, the second node may carry an end flag in the last data packet sent to the first node to indicate that the third data transmission of the second node is completed. Accordingly, the first node may respond to the last data packet, and if it is detected that the first node still has a remaining NAV duration on the channel, the first node may continue to share the remaining NAV duration to other nodes, which may be described below with reference to fig. 7A.

In an embodiment, after the second node sends the last data packet to the first node, if the second node detects that the first node still has a remaining NAV duration on the channel, the second node may continue to share the remaining NAV duration to other nodes, and the way of sharing to other nodes may refer to the following description of fig. 7A.

In this embodiment, the second node may continuously transmit data for multiple times by using the remaining NAV duration of the first node, so as to improve the utilization rate of the channel. In addition, the first node can share the remaining NAV duration of the first node to a plurality of nodes, and also can improve the utilization rate of the channel and reduce the difficulty and time delay of accessing the channel by the node.

The foregoing embodiment describes that the channel access method provided in this embodiment may be applied to a scenario in which the first node shares the remaining NAV duration with the peer node, and in an embodiment, the channel access method provided in this embodiment may also be applied to a scenario in which the first node shares the remaining NAV duration with the third node. The third node is not a peer node of the first node, and is a node which requires to compete for accessing the same channel as the first node. The following description will first take a scenario as an example to develop and introduce the channel access method provided by the embodiment of the present application.

Fig. 6 is a schematic view of another scenario applicable to the embodiment of the present application. Referring to fig. 6, the scenario may include an AP, and a plurality of STA devices. The AP may be a router, and the STA device may be a smart screen, a point of sale (POS) machine, or the like in a shopping mall. Because the priority of the screen projection service is higher, the smart screen has strong access capability compared with the POS machine to compete for the access channel, so that the problem that the POS machine cannot compete for the access channel easily occurs in the scene, and the POS machine cannot swipe the card and the like is caused. In order to solve the problem, in the channel access method provided in this embodiment of the present application, an AP may manage multiple STA devices accessing the AP, and share the remaining NAV duration of the AP with the STA devices that cannot compete for accessing the channel for a long time, so that the STA devices that cannot compete for accessing the channel for a long time, for example, a POS machine may access the channel and normally process services such as card swiping, and the like, which specifically refers to the related description in fig. 7A.

Fig. 7A is a flowchart illustrating a channel access method according to another embodiment of the present application. Referring to fig. 7A, a channel access method provided in an embodiment of the present application may include:

s701, the first node sends first data to the second node on a channel.

S701 may refer to the description related to S201. For example, in the scenario shown in fig. 6, the first node may be an AP, and the second node may be any STA device connected to the AP. For example, in a video conference scenario, the first node may be a router, the second node may be a tablet computer or a smart screen, and the first data sent by the first node to the second node may be video conference data.

S702, if the first node has the first remaining NAV duration on the channel, the first node sends NAV sharing information to the third node on the channel, and the NAV sharing information indicates the third node to send data on the channel.

The opposite node of the first node is the second node, after the first node finishes sending the data packet to the second node, if the first node has the first remaining NAV duration on the channel, the first node may send NAV sharing information to the third node on the channel, and the NAV sharing information indicates the third node to send data on the channel.

When the first node shares the first remaining NAV duration with the third node, the third node may be determined first. In one embodiment, the third node may be: a node connected to the first node but not accessing the channel for a long time. The long time without accessing the channel can be understood as: the time length of the node not accessing the channel is greater than or equal to the preset time length. Accordingly, the first node can take a node which has not accessed the channel for a long time as a third node. In one embodiment, the third node may be: the node with the highest traffic priority.

For example, taking the scenario in fig. 6 as an example, the AP is connected to a POS device, an intelligent screen, and the like. In an embodiment, the AP may detect whether a device such as a POS and a smart screen connected to the AP has not accessed the channel for a long time, and if so, the AP may use the device that has not accessed the channel for a long time as the third node. It should be understood that the device accessing the channel may send a data packet on the channel, and the AP may analyze the MAC layer of the data packet to obtain the device occupying the channel, and further may obtain the device not accessing the channel for a long time, so as to determine the third node not accessing the channel for a long time.

In an embodiment, the AP may determine service priorities of the POS device and the smart screen device based on historical interaction data with the POS device and the smart screen device, and then use the device with the highest service priority as the third node. For example, in the quality of service (QoS) mechanism specified by the current IEEE802.11 protocol, the priority of the queue of the service is, from high to low: a Voice (VI) queue, a Video (VO) queue, a Best Effort (BE) queue, and a Background (BK) queue. Accordingly, the AP may determine the service priority of the POS device, the smart screen device, and the like based on the queue of the service where the history and the interactive data of the POS device, the smart screen, and the like are located, so as to determine the third node with the highest service priority.

Alternatively, referring to fig. 8, node a, node B, node C and node D are nodes in one island of the HiD2D, node a is connected to node B, node C is connected to node D, and node a is not connected to node C and node D, but since node a, node B, node C and node D are one island of the HiD2D, node a, node B, node C and node D operate on the same channel, e.g., 36 channels. It should be understood that node a, node B, node C and node D may share respective connection information in the social channel of the HiD2D, and the connection information may include: traffic channels, communication slots, traffic types, etc. In this way, a node located in one island may obtain the service type of other nodes in the island in the social channel, and in addition, the node may also obtain the MAC address of other nodes in the island based on the Media Access Control (MAC) address that transmits the connection information. That is, a node located in one island can obtain information such as the service type and MAC address of other nodes in the island in the social channel.

Thus, taking the scenario in fig. 8 as an example, in an embodiment, in the same island, a node accessing a channel may send a data packet on the channel, and a node a located in one island may analyze the MAC layer of the data packet, obtain the MAC address of a device occupying the channel, and further obtain a device not accessing the channel for a long time based on the MAC address of the node occupying the channel, so as to determine a third node not accessing the channel for a long time.

In one embodiment, node a may obtain the service type of each node in the island in the social channel, and node a may determine the third node based on the service type of each node. Illustratively, the node a may take a node with a high priority of traffic as the third node. If the service type of the node C is the screen projection service, the screen projection service has a high priority, so the node a may use the node C as a third node, and use the node D as an opposite node of the node C in fig. 8. The node a may be regarded as a first node, and the node B may be regarded as a second node.

For example, referring to table two, the priority of the traffic may be as shown in table two, and the priority characterizing the traffic gradually decreases from 0 to 5:

watch two

It should be understood that fps characterizes the number of frames per second (frames per second) transmitted.

In this embodiment, because the third node is not a peer node of the first node, in an embodiment, referring to fig. 9A, the first node sends the last data packet to the second node, and may send an aid frame to the third node on the channel after an SIFS interval, where the aid frame includes NAV sharing information. The NAV sharing information may include: the remaining NAV duration of the first node and/or an indication, such as an end flag, indicating completion of the transmission of the data packet. The format of the aid frame may refer to the relevant description in the above embodiments. It should be appreciated that for the scenario illustrated in fig. 8 described above, the aid frame sent by the first node to the third node may be a management frame.

In one embodiment, referring to fig. 9B, the first node may send an aid frame to the third node on the channel after an interval of one SIFS in response to sending the last packet to the second node and receiving a TCP ACK fed back from the second node.

As described above, the first node may select a third node among the non-correspondent nodes, and then transmit NAV sharing information to the third node.

S703, the third node responds to the NAV sharing information, and judges whether the transmission of the second data of the third node can be completed within the first remaining NAV duration; if yes, go to step S704, otherwise go to step S705.

In one embodiment, the NAV sharing information may include a first remaining NAV duration of the first node, whereby the third node is able to acquire the first remaining NAV duration of the first node. In an embodiment, because the third node can resolve the MAC frame of the data packet from the first node, the third node may acquire the first remaining NAV duration of the first node, which may refer to the related description in S201.

When the third node receives the NAV sharing information from the first node, it may determine whether the transmission of the second data of the third node can be completed within the first remaining NAV duration, and the process may refer to the related description of the second node in S203. For example, taking the fourth node as an opposite node of the third node, the third node is a POS, and the fourth node is a mobile phone, the second data may be: and the POS machine sends a card swiping request to the mobile phone. For example, taking the fourth node as the opposite node of the third node, the third node is a mobile phone, and the fourth node is an intelligent screen, the second data may be: and screen projection data sent to the intelligent screen by the mobile phone.

In one embodiment, the third node determines whether the transmission of the second data of the third node can be completed within the first remaining NAV duration of the first node, that is, it needs to determine whether the "transmission of the second data of the third node" and the "feedback of the fourth node" can be completed within the first remaining NAV duration. For example, if the mobile phone sends screen-projecting data to the smart screen, the mobile phone needs to determine whether the transmission of the screen-projecting data can be completed within the first remaining NAV duration, and receive TCP ACK from the smart screen.

If the sum of the duration of transmitting the second data and the duration of feeding back by the fourth node is less than or equal to the first remaining NAV duration, the third node determines that the transmission of the second data by the third node and the feeding back by the fourth node can be completed. If the sum of the duration of transmitting the second data and the duration of feeding back by the fourth node is greater than the first remaining NAV duration, the third node determines that the transmission of the second data by the third node and the feeding back by the fourth node cannot be completed.

S704, the third node transmits the second data to the fourth node on the channel.

Referring to fig. 9A and 9B, the third node may send the second data to the fourth node on the channel within the first remaining NAV duration, and both fig. 9A and 9B take the third node sending the last data packet to the fourth node as an example. Illustratively, the POS machine sends a card swiping request to the mobile phone, or the mobile phone can send screen throwing data to the smart screen. Thus, referring to the scenario shown in fig. 6, the AP may share the remaining NAV duration of the AP with the POS, so that the POS may access the channel without contention, complete services such as card swiping of the POS, and achieve that a node that cannot contend for accessing the channel for a long time may smoothly transmit data on the channel.

In an embodiment, if the third node determines that the transmission of the second data of the third node and the feedback of the fourth node can be completed within the first remaining NAV duration, after the third node sends the second data to the fourth node, the third node may share the second remaining NAV duration of the first node to the fourth node, so that the fourth node may feed back the data to the third node on the channel within the second remaining NAV duration, as shown in fig. 9A and 9B, taking as an example that the fourth node feeds back a TCP ACK to the third node within the second remaining NAV duration, the process may refer to the above-mentioned description of "the first node shares the first remaining NAV duration to the second node" or "the first node shares the first remaining NAV duration to the third node".

Taking fig. 9B as an example, the fourth node may feed back data to the third node within the second remaining NAV duration. For example, a smart screen may feed back TCP ACK to the handset.

S705, when the NAV value of the first node decreases to 0, the first node, the second node, and the third node compete to access the channel.

S705 may refer to the description related to S205, which is not described herein.

The channel access method in the embodiment of the present application may be applied to, but is not limited to: in a scenario where the AP is connected to multiple STA devices, in a scenario of the same island in the HiD 2D.

In the embodiment of the application, the first node can share the remaining NAV duration of the first node with a third node which cannot compete for the channel for a long time or with a third node with a high priority of the service type, so that the third node can access the channel to execute the service of the third node, and the channel access capability of the third node is increased while the channel utilization rate is improved. The embodiment of the present application also has the same technical effects as those of the above embodiments, and reference may be made to the related description of the above embodiments.

In the embodiment shown in fig. 7A, in a possible scenario, if the first node shares the first remaining NAV duration to the third node which does not access the channel for a long time, and the third node has no data to send, in this scenario, referring to fig. 7B, the above-mentioned S703-S705 may be replaced with S703A-S704A.

S703A, the third node feeds back first information to the first node, and the first information represents that the third node does not need to access a channel.

The third node can feed back the first information to the first node because no data needs to be sent on the channel, and the first information represents that the third node does not need to access the channel, so that the first node can share the remaining NAV duration with other nodes. In one embodiment, the first information may be an aid frame, which may include a remaining NAV duration of the first node.

S704A, the first node sends an aid frame to the fifth node.

In one embodiment, the fifth node is similar to the third node, e.g., the fifth node may be a node that has not accessed the channel for a long time, or a node with a high priority traffic type. It should be understood that, when the fifth node is a node which has not accessed the channel for a long time, the first node may take the node which has not accessed the channel and has the first time length as the third node, and take the node which has not accessed the channel and has the second time length as the fifth node. In the embodiment of the present application, a manner of selecting the fifth node from the first node is not limited.

It should be noted that the aid frame may include NAV sharing information, which indicates a second remaining NAV duration of the first node, which is less than the first remaining NAV duration. The aid frame instructs the fifth node to send data on the channel. It should be understood that after the fifth node receives the aid frame from the first node, the above S703-S705 may be performed, or the above S703A may be performed, and reference may be made to the above description.

In an embodiment, if the first node shares the first remaining NAV duration to the third node that does not access the channel for a long time, and if the third node has no data to send, in such a scenario, referring to fig. 7C, the above S703-S705 may also be replaced with S703B.

S703B, the third node sends an aid frame to the fifth node.

In order to save the remaining NAV duration of the first node, when the third node has no data to transmit, the third node may directly transmit an aid frame to the fifth node to instruct the fifth node to transmit data on the channel, without passing through the first node. It should be understood that the steps as in S703-S705, or the steps as in S703A, may be performed after the fifth node receives the aid frame from the first node, and reference may be made to the above-mentioned related description.

In this embodiment of the present application, when the first node shares the first remaining NAV duration with the third node and the third node has no data to send on the channel, the third node may directly share the remaining NAV duration of the first node with the fifth node, or the third node may share the remaining NAV duration of the first node with the fifth node through the first node, both of which may achieve the purpose of effectively utilizing the remaining NAV duration of the first node and improving the channel utilization rate.

The above embodiment describes a scheme in which the first node may share the NAV duration remaining for the first node to the correspondent node (second node) or the non-correspondent node (third node).

In one embodiment, the first node may determine to share the first remaining NAV duration to the second node or the third node based on the first remaining NAV duration. If the first remaining NAV duration is greater than or equal to the first preset duration and less than the second preset duration, the amount of data capable of being transmitted in the first remaining NAV duration is limited, and most of second nodes interacting with the first node feed back TCP ACK to the first node, and the occupied duration is small, so that the first node can share the first remaining NAV duration to the second node, that is, the first node sends NAV sharing information to the second node, for example, the second node feeds back TCP ACK to the first channel on a channel, so that the first node and the second node complete one interaction. And the second preset time length is greater than the first preset time length.

If the first remaining NAV duration is greater than or equal to the second preset duration, the amount of data which can be transmitted in the first remaining NAV duration is large, because the third node interacts with the fourth node, the third node serves as an initiating end of the interaction, and the duration of the transmitted data is longer than the duration of transmitting the TCP ACK, so that the first node can share the first remaining NAV duration to the third node, that is, the first node sends NAV sharing information to the third node, and the third node interacts with the fourth node on a channel.

In this way, the first node may select a target node sharing the first remaining NAV duration based on the first remaining NAV duration, which may improve flexibility.

In an embodiment, if the first remaining NAV duration is greater than or equal to a third preset duration, and the third preset duration is greater than the second preset duration, that is, the first remaining NAV duration is greater, the first node may share the first remaining NAV duration to a node with a high priority based on the priorities of the second node and the third node, and then share the second remaining NAV duration to a node with a low priority.

For example, if the second node is a peer node of the first node, the priority of the peer node is higher than that of the non-peer node, so that the interaction between the first node and the second node can be ensured. Thus, the first node may first share the first remaining NAV duration with the second node, and after the second node transmits data on the channel, the first node may still have the second remaining NAV duration on the channel, and the first node (or the second node) may share the second remaining NAV duration with the third node, as shown in fig. 10A.

In an embodiment, in a scenario of one island of the HiD2D, the first node may obtain the service type of each slave device in the social channel, and based on the priority of the service types of the second node and the third node, the first node may share the first remaining NAV duration to the node with the higher priority of the service type, and then share the second remaining NAV duration to the node with the lower priority of the service type.

For example, if the service type of the second node is to send the reverse touch data, the service type of the third node is to send the screen projection service, and the priority of the screen projection service is higher than the priority of sending the reverse touch data, the first node may share the first remaining NAV duration to the third node, and after the third node sends the screen projection data on the channel, the first node still has the second remaining NAV duration on the channel, the first node (or the third node) may share the second remaining NAV duration to the second node, which may be shown in fig. 10B, where fig. 10B illustrates an example where the third node shares the second remaining NAV duration to the second node.

In this embodiment, the first node may determine, based on the first remaining NAV duration, to share the remaining NAV duration of the first node with the second node and/or the third node, so that the second node and/or the third node may transmit data on the channel, and the flexibility of sharing the remaining NAV duration by the first node is high.

In summary, referring to fig. 11, a channel access method provided in an embodiment of the present application may include:

the first node transmits NAV sharing information to the target node in response to detecting the first remaining NAV duration of the first node, the NAV sharing information indicating that the target node transmits data on the channel S1101.

The target node may be the second node or the third node. The first node selects the target node based on the first remaining NAV duration, which may be as described with reference to the above embodiments.

S1102, the target node responds to the NAV sharing information and judges whether the transmission of the second data of the target node can be completed within the first residual NAV duration; if so, go to S1113, otherwise, go to S1114.

S1103, the target node sends the second data to the opposite node of the target node on the channel.

It should be understood that, when the target node is the second node, the opposite node of the target node is the first node, and the target node is taken as the second node in fig. 11 for illustration. And when the target node is the third node, the opposite end node of the target node is the fourth node.

S1104, when the NAV value of the first node decreases to 0, the first node and the target node contend to access the channel.

S1101-S1104 may refer to the related description in the above embodiments, and are not described herein again. It should be appreciated that the target node detects that the first node has a second remaining NAV duration on the channel, and continues to transmit third data on the channel to the correspondent node of the target node. Or the second remaining NAV duration may be shared with other nodes, as described in the foregoing embodiments.

Fig. 12 is a schematic structural diagram of a channel access apparatus according to an embodiment of the present application. The channel access device may be the first node as in the above embodiments, or a chip in the first node, etc. Referring to fig. 12, in one embodiment, a channel access apparatus 1200 may include: a transceiver module 1201 and a processing module 1202. Wherein the content of the first and second substances,

a transceiver module 1201, configured to: the method comprises the steps of sending first data to a second node on a channel, and responding to the fact that a first residual Network Allocation Vector (NAV) duration exists on the channel of the first node, sending first NAV sharing information to a target node on the channel, wherein the first NAV sharing information indicates the target node to send data on the channel, the target node is the second node or a third node, a traffic channel of the third node is the channel, and the third node is different from the second node.

In a possible implementation manner, the transceiver module 1201 is specifically configured to: and responding to the first node that a first residual NAV duration exists on the channel and the first residual NAV duration is larger than or equal to a first preset duration, and sending the first NAV sharing information to the target node on the channel.

In one possible implementation manner, when the first remaining NAV duration is greater than or equal to the first preset duration and is less than the second preset duration, the target node is the second node, and when the first remaining NAV duration is greater than or equal to the second preset duration, the target node is the third node, and the second preset duration is greater than the first preset duration.

In a possible implementation manner, the transceiver module 1201 is specifically configured to: and sending a mutual aid channel access aid frame to the target node on the channel, wherein the aid frame comprises the first NAV sharing information.

In a possible implementation manner, the transceiver module 1201 is further configured to: when the target node is the second node, in response to receiving second data from the second node and a second remaining NAV duration existing on the channel by the first node, transmitting second NAV sharing information to other nodes on the channel, the second NAV sharing information indicating that the other nodes transmit data on the channel; alternatively, the first and second electrodes may be,

In one possible implementation, the processing module 1202 is configured to: setting the NAV time length of the first node; and in the NAV duration of the first node, the first node and the second node compete to access the channel.

Fig. 13 is a schematic structural diagram of a channel access apparatus according to an embodiment of the present application. The channel access device may be a target node as in the above embodiments, or a chip in the target node, etc., and the target node may be a second node or a third node as in the above embodiments. Referring to fig. 13, in one embodiment, a channel access apparatus 1300 may include: a transceiver module 1301 and a processing module 1302. Wherein the content of the first and second substances,

a transceiver module 1301, configured to: receiving, on a channel, first Network Allocation Vector (NAV) sharing information from a first node, where the first NAV sharing information indicates that a target node sends data on the channel, the target node is a second node or a third node, the second node is an opposite node of the first node, or a traffic channel of the third node is the channel and the third node is different from the second node.

In a possible implementation manner, the transceiver module 1301 is specifically configured to: receiving a mutual aid channel access aid frame from the first node on the channel, wherein the aid frame comprises the first NAV sharing information.

In a possible implementation manner, if the target node is the second node, the transceiver module 1301 is further configured to: receiving first data from the first node on the channel, the first data consisting of at least one data packet, the first NAV sharing information being carried in a last data packet of the at least one data packet.

In a possible implementation manner, the transceiver module 1301 is further configured to: and based on the first residual NAV duration of the first node, if the second data can be transmitted in the first residual NAV duration, the second data is sent to the opposite end node of the target node on the channel.

In a possible implementation manner, the transceiver module 1301 is further configured to: and responding to the first node that a second residual NAV duration exists on the channel and the transmission of third data can be completed in the second residual NAV duration, and sending the third data to an opposite node of the target node on the channel.

In a possible implementation manner, the second data is a minimum data unit that the target node supports to send.

In one possible implementation, the processing module 1302 is configured to: and if it is determined that the transmission of the second data cannot be completed within the first remaining NAV duration based on the first remaining NAV duration of the first node, contending with the first node for accessing the channel when the NAV duration of the first node is reduced to 0, wherein the NAV duration of the first node is set when the first node accesses the channel.

In a possible implementation manner, the transceiver module 1301 is further configured to: and responding to the target node without the data to be sent, sending first information to the first node, wherein the first information indicates that the target node does not have the data to be sent.

In a possible implementation manner, the transceiver module 1301 is further configured to: and responding to the target node without the data to be sent, sending third NAV sharing information to other nodes, wherein the third NAV sharing information indicates the other nodes to send the data on the channel.

It should be understood that, in the embodiment of the present application, the channel access apparatus provided in fig. 12 can perform the action of the first node in the above embodiment, and the channel access apparatus provided in fig. 13 can perform the action of the target node in the above embodiment, thereby achieving the same technical effect as that in the above embodiment, which is not described herein again.

In an embodiment, an electronic device is provided in this embodiment, and the electronic device may be the first node, the second node, or the third node in the foregoing embodiments. The electronic device may include: a processor (e.g., CPU), memory, and a transceiver. The memory and the transceiver may be coupled to the processor electronics, which controls the transceiver to perform transceiving actions of the electronic device to enable interaction between the electronic device and the cloud. The memory may include a random-access memory (RAM) or a non-volatile memory (NVM), such as at least one disk memory, and may store various instructions for performing various processing functions and implementing the method steps of the present application. The transceiver may be integrated in a transceiver of the electronic device, or may be a separate transceiver antenna on the electronic device. In an embodiment of the present application, the memory is used for storing computer executable program code, and the program code includes instructions; when the processor electronic device executes the instruction, the instruction causes the processor electronic device of the electronic device to execute the actions in the above method embodiments, which have similar implementation principles and technical effects, and are not described herein again. Optionally, the electronic device related to the present application may further include: a power supply, a communication bus, and a communication port. The communication bus is used for realizing communication connection among the elements. The communication port is used for realizing connection communication between the electronic equipment and other peripheral equipment.

It should be noted that the above modules may be one or more integrated circuits configured to implement the above methods, for example: one or more Application Specific Integrated Circuits (ASICs), or one or more microprocessors (DSPs), or one or more Field Programmable Gate Arrays (FPGAs), among others. For another example, when some of the above modules are implemented in the form of a processing element scheduler code, the processing element may be a general-purpose processor, such as a Central Processing Unit (CPU) or other processor that can call program code. As another example, these modules may be integrated together, implemented in the form of a system-on-a-chip (SOC).

In the above embodiments, the implementation may be wholly or partially realized by software, hardware, firmware, or any combination thereof. When implemented in software, it may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. The procedures or functions according to the embodiments of the present application are all or partially generated when the computer program instructions are loaded and executed on a computer. The computer may be a general purpose computer, a special purpose computer, a network of computers, or other programmable device. 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, for example, the computer instructions may be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, digital Subscriber Line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device, such as a server, a data center, etc., that incorporates one or more of the available media. The usable medium may be a magnetic medium (e.g., floppy Disk, hard Disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium (e.g., solid State Disk (SSD)), among others.

The term "plurality" herein refers to two or more. The term "and/or" herein is merely an association describing an associated object, meaning that three relationships may exist, e.g., a and/or B, may mean: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" herein generally indicates that the former and latter related objects are in an "or" relationship; in the formula, the character "/" indicates that the preceding and following related objects are in a relationship of "division".

It is to be understood that the terms "first," "second," and the like, in the description of the present application, are used for distinguishing between descriptions and not necessarily for describing a sequential or chronological order, or for indicating or implying a relative importance.

It is to be understood that the various numerical references referred to in the embodiments of the present application are merely for descriptive convenience and are not intended to limit the scope of the embodiments of the present application. In the embodiment of the present application, the sequence numbers of the above-mentioned processes do not mean the execution sequence, and the execution sequence of each process should be determined by its function and inherent logic, and should not constitute any limitation to the implementation process of the embodiment of the present application.

Claims

1. A channel access method applied to a first node, the method comprising:

transmitting first data to a second node over a channel;

responding to the first node that a first residual Network Allocation Vector (NAV) duration exists on the channel, and sending first NAV sharing information to a target node on the channel, wherein the first NAV sharing information indicates that the target node sends data on the channel, the target node is the second node or a third node, a traffic channel of the third node is the channel, and the third node is different from the second node.

2. The method of claim 1, wherein the sending first NAV-sharing information to a target node on the channel in response to the first node having a first remaining Network Allocation Vector (NAV) duration on the channel comprises:

and responding to the first node that a first residual NAV duration exists on the channel and the first residual NAV duration is larger than or equal to a first preset duration, and sending the first NAV sharing information to the target node on the channel.

3. The method of claim 2, wherein the target node is the second node when the first remaining NAV duration is greater than or equal to the first predetermined duration and less than a second predetermined duration, wherein the target node is the third node when the first remaining NAV duration is greater than or equal to the second predetermined duration, and wherein the second predetermined duration is greater than the first predetermined duration.

4. The method according to any of claims 1-3, wherein said transmitting first NAV-sharing information to a target node on the channel comprises:

and sending a mutual aid channel access aid frame to the target node on the channel, wherein the aid frame comprises the first NAV sharing information.

5. The method according to any of claims 1-3, wherein the first data consists of at least one data packet, and wherein the first NAV-sharing information is carried in a last data packet of the at least one data packet.

6. The method according to any of claims 1-5, wherein the first NAV sharing information comprises: the first remaining NAV duration, and/or an indication indicating that the first data transmission is complete.

7. The method according to any of claims 1-6, wherein the third node is: and the node with the duration of the uncontended access channel being greater than or equal to the preset duration, or the node with the highest service priority.

8. The method according to any one of claims 1-7, further comprising:

when the target node is the second node, in response to receiving second data from the second node and a second remaining NAV duration existing on the channel by the first node, transmitting second NAV sharing information to other nodes on the channel, the second NAV sharing information indicating that the other nodes transmit data on the channel; alternatively, the first and second electrodes may be,

9. The method of any of claims 1-8, wherein prior to transmitting the first data to the second node over the channel, further comprising:

setting the NAV time length of the first node;

and when the NAV time length of the first node is reduced to 0, the first node and the second node compete to access the channel.

10. A channel access method applied to a target node, the method comprising:

receiving, on a channel, first Network Allocation Vector (NAV) sharing information from a first node, where the first NAV sharing information indicates that a target node sends data on the channel, and the target node is a second node or a third node, where the second node is an opposite node of the first node, or a traffic channel of the third node is the channel and the third node is different from the second node.

11. The method according to claim 10, wherein receiving the first network allocation vector, NAV, sharing information from the first node over the channel comprises:

receiving a mutual aid channel access aid frame from the first node on the channel, wherein the aid frame comprises the first NAV sharing information.

12. The method of claim 10, wherein if the target node is the second node, before receiving the first network allocation vector NAV share information from the first node on the channel, further comprising:

receiving first data from the first node on the channel, the first data consisting of at least one data packet, the first NAV sharing information being carried in a last data packet of the at least one data packet.

13. The method according to any of claims 10-12, wherein the first NAV sharing information comprises: a first remaining NAV duration of the first node, and/or an indication indicating completion of transmission of first data from the first node.

14. The method according to any of claims 10-13, wherein the third node is: and the node with the duration of the uncontended access channel being greater than or equal to the preset duration, or the node with the highest service priority.

15. The method according to any of claims 10-14, wherein after receiving the first network allocation vector, NAV, sharing information on the channel from the first node, further comprising:

and based on the first residual NAV duration of the first node, if the second data can be transmitted in the first residual NAV duration, the second data is sent to the opposite end node of the target node on the channel.

16. The method of claim 15, wherein after sending the second data to the peer node of the target node over the channel, further comprising:

and responding to the first node that a second residual NAV duration exists on the channel and the transmission of third data can be completed in the second residual NAV duration, and sending the third data to an opposite node of the target node on the channel.

17. The method according to claim 15 or 16, wherein the second data is the smallest data unit that the target node supports sending.

18. The method according to any of claims 10-17, wherein after receiving the first network allocation vector, NAV, sharing information on the channel from the first node, further comprising:

and if it is determined that the transmission of the second data cannot be completed within the first remaining NAV duration based on the first remaining NAV duration of the first node, contending with the first node for accessing the channel when the NAV duration of the first node is reduced to 0, wherein the NAV duration of the first node is set when the first node accesses the channel.

19. The method according to any of claims 10-17, wherein after receiving the first network allocation vector, NAV, sharing information on the channel from the first node, further comprising:

and responding to the target node without the data to be sent, sending first information to the first node, wherein the first information indicates that the target node does not have the data to be sent.

20. The method according to any of claims 10-17, wherein after receiving the first network allocation vector, NAV, sharing information on the channel from the first node, further comprising:

and responding to the target node without the data to be sent, sending third NAV sharing information to other nodes, wherein the third NAV sharing information indicates the other nodes to send the data on the channel.

21. A channel access apparatus, comprising:

a transceiver module for:

transmitting first data to a second node over a channel;

responding to a first node that has a first residual Network Allocation Vector (NAV) duration on the channel, and sending first NAV sharing information to a target node on the channel, wherein the first NAV sharing information indicates that the target node sends data on the channel, the target node is the second node or a third node, a traffic channel of the third node is the channel, and the third node is different from the second node.

22. A channel access apparatus, comprising:

the receiving and sending module receives first Network Allocation Vector (NAV) sharing information from a first node on a channel, wherein the first NAV sharing information indicates a target node to send data on the channel, the target node is a second node or a third node, the second node is an opposite end node of the first node, or a service channel of the third node is the channel, and the third node is different from the second node.

23. An electronic device, comprising: a memory, a processor;

the processor is coupled to the memory, and reads and executes instructions in the memory to implement the method of any one of claims 1-20.

24. A computer-readable storage medium having stored thereon computer instructions which, when executed by a computer, cause the computer to perform the method of any one of claims 1-20.