CN107926061B

CN107926061B - Back-off method, message transmission method and device

Info

Publication number: CN107926061B
Application number: CN201580082472.9A
Authority: CN
Inventors: 丁志明; 禄·彼得
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2015-08-21
Filing date: 2015-08-21
Publication date: 2020-07-14
Anticipated expiration: 2035-08-21
Also published as: CN107926061A; WO2017031645A1

Abstract

A back-off method and device comprises the following steps: the first node starts a backoff counter; and after the first node determines that the channel corresponding to the started backoff counter is occupied by the second node in a space multiplexing mode and cannot occupy the channel together with the second node in the space multiplexing mode, continuing counting the backoff counter or reducing the count value of the backoff counter. A method and a device for transmitting messages comprise the following steps: a first node determines that the first node is occupying a channel; the first node sends a message through the channel, wherein the message comprises spatial multiplexing indication information; the spatial multiplexing indication information is used for indicating a receiving node of the message to determine an occupation mode of the first node occupying the channel according to the spatial multiplexing indication information, and when the first node occupies the channel through the spatial multiplexing mode, indicating the receiving node of the message to occupy the channel through a competition mode and then sending a response message to the first node; and/or the spatial multiplexing indication information is used for indicating a non-receiving node which listens to the channel to determine an occupation mode of the first node occupying the channel according to the spatial multiplexing indication information, and when the first node occupies the channel in a spatial multiplexing mode, indicating the non-receiving node which listens to the channel to occupy the channel after waiting for the channel to be free.

Description

Back-off method, message transmission method and device

Technical Field

The present invention relates to the field of communications technologies, and in particular, to a back-off method, a message transmission method, and an apparatus.

Background

With the development of mobile internet and the popularization of intelligent terminals, data traffic is rapidly increasing, W L AN (Wireless L optical Area Network, Wireless local Area Network) is one of mainstream mobile broadband access technologies by virtue of its advantages of high rate and low cost.

Before preparing to send a message, the STA or AP randomly generates a number as a count value in a backoff counter (backoff counter), and then starts to monitor the channel, when it is determined that the channel is in AN idle state within a time slot (time slot), the count value in the backoff counter performs a decrementing operation, when it is determined that the channel is in a non-idle state, the count value in the backoff counter stops decrementing until the channel is idle, and when the count value in the backoff counter decreases to 0, the STA or AP may send a message.

In order to improve communication efficiency, SR (spatial reuse) technology is proposed in the next generation wireless local area network standard 802.11ax, and two neighboring home nodes adopting the SR technology can simultaneously transmit messages. For example, as shown in fig. 1, a multi-node distribution diagram according to an embodiment of the present invention is provided. In fig. 1, STA3 and STA2 cover each other, STA3 and STA5 cover each other, and STA2 and STA5 are far away from each other and do not cover each other. Suppose STA2 wants to transmit data to STA1, STA3 wants to transmit data to STA4, and STA5 wants to transmit data to STA6, and STA2, STA3, and STA5 need to contend for the channel. Referring to fig. 1, as shown in fig. 2, a multi-node transmission diagram according to an embodiment of the present invention is provided. In fig. 2, STA2, STA3, and STA5 randomly generate initial count values R1, R2, and R3, respectively, and R1< R2< R3, and the three STAs start counting because the channel is idle. STA2 first counts to 0 and then begins to seize the channel and send a message. When STA2 begins transmitting messages, STA3 listens to the transmitted messages of STA2 and stops counting. Meanwhile, STA3 needs to determine the reception power of the message transmitted by receiving STA2 and obtain the information such as the sender id, the receiver id, and the transmission power from the received message transmitted by STA 2. STA3 judges from these pieces of information that if STA3 and STA2 transmit a message at the same time, it will not affect the message transmitted by STA2 on the receiver side receiving STA2 of the message transmitted from STA2, and if it is determined that it will not affect it, it will transmit at the same time with STA 2. When STA3 is listening for messages transmitted by STA2, STA5 does not listen for messages transmitted by STA2 and STA3, considers the channel to be idle, and continues to count. Thereafter, when STA3 transmits a message simultaneously with STA2, STA5 stops counting until STA3 ends transmission of the message, and STA5 resumes counting. Note that STA3 needs to end the transmission of the message at the same time when STA2 ends the transmission of the message, so as not to affect STA1 from transmitting an Acknowledgement (ACK) frame to STA 2.

In the above procedure, originally, both STA2 and STA5 send messages to cause STA3 to stop the backoff process, while STA5 only stops the backoff process when STA3 sends messages, after the SR technique is adopted, because STA3 and STA2 can send messages simultaneously, STA2 contends for the channel to be equal to that of STA3, which helps STA3 to occupy the channel, and causes STA5 to use the channel to be greatly reduced.

In summary, in the wireless local area network adopting the SR technology, the opportunity that a node delayed from occupying a channel occupies the channel is reduced, so that the node cannot normally compete for the channel, thereby reducing the utilization rate of the node for the channel.

Disclosure of Invention

The embodiment of the invention provides a backoff method, a message transmission method and a message transmission device, which are used for ensuring that in a wireless local area network adopting an SR technology, the opportunity that a node delayed from occupying a channel occupies the channel is improved.

In a first aspect, a backoff method is provided, where the method includes:

the first node starts a backoff counter;

and after the first node determines that the channel corresponding to the started backoff counter is occupied by the second node in a space multiplexing mode and cannot occupy the channel together with the second node in the space multiplexing mode, continuing counting the backoff counter or reducing the count value of the backoff counter.

With reference to the first aspect, in a first possible implementation manner of the first aspect, before the first node does not pause the backoff counter or reduces a count value of the backoff counter, the method further includes:

the first node determines that no other neighbor nodes except the second node exist in the signal coverage range of the first node; alternatively, the first and second electrodes may be,

the first node determines that no other neighbor nodes except the second node and the receiving node of the first node exist in the signal coverage range of the first node.

With reference to the first aspect or the first possible implementation manner of the first aspect, in a second possible implementation manner of the first aspect, the first node decreases the count value of the backoff counter and suspends the backoff counter.

With reference to the first aspect or the first possible implementation manner of the first aspect, in a third possible implementation manner of the first aspect, the reducing, by the first node, the count value of the backoff counter includes:

and the first node periodically reduces the count value of the backoff counter during the period that the second node occupies the channel.

With reference to the first aspect or the first possible implementation manner of the first aspect, in a fourth possible implementation manner of the first aspect, the reducing, by the first node, the count value of the backoff counter includes:

the first node multiplies the current count value of the backoff counter by a coefficient and rounds the count value, wherein the coefficient is greater than 0 and less than 1;

and the first node takes the rounded value as the current count value of the backoff counter.

With reference to the first aspect or the first possible implementation manner of the first aspect, in a fifth possible implementation manner of the first aspect, the reducing, by the first node, the count value of the backoff counter includes:

if the difference value between the current count value of the backoff counter and the threshold is less than 0, the first node takes 0 as the current count value of the backoff counter;

and if the difference value between the current count value of the backoff counter and the threshold is not less than 0, the first node takes the difference value as the current count value of the backoff counter.

With reference to the first aspect or the first possible implementation manner of the first aspect, in a sixth possible implementation manner of the first aspect, the first node determines whether the second node occupies the channel in a spatial multiplexing manner according to the following manner:

the first node monitors a first message sent by the second node to other nodes, wherein the first message comprises spatial multiplexing indication information, and the spatial multiplexing indication information is used for indicating an occupation mode of the second node occupying the channel;

and the first node determines whether the second node occupies the channel in a spatial multiplexing mode according to the spatial multiplexing indication information in the first message.

With reference to the first aspect or any one of the first to sixth possible implementation manners of the first aspect, in a seventh possible implementation manner of the first aspect, the method further includes:

after occupying a channel, the first node sends a second message through the channel, wherein the second message comprises spatial multiplexing indication information, and the spatial multiplexing indication information is used for indicating an occupation mode of the channel occupied by the first node.

With reference to the seventh possible implementation manner of the first aspect, in an eighth possible implementation manner of the first aspect, the spatial multiplexing indication information is located in an HE signaling HE-SIG of the physical header of the message.

With reference to the first aspect or any one of the first to eighth possible implementation manners of the first aspect, in a ninth possible implementation manner of the first aspect, the method further includes:

the first node receives a third message sent by a third node, wherein the third message comprises spatial multiplexing indication information;

and after determining the channel occupied by the third node in the spatial multiplexing mode according to the spatial multiplexing indication information in the third message, the first node occupies the channel in a competition mode and then sends a response message to the third node through the channel.

In a second aspect, a method for transmitting a message is provided, the method comprising:

a first node determines that the first node is occupying a channel;

the first node sends a message through the channel, wherein the message comprises spatial multiplexing indication information;

the spatial multiplexing indication information is used for indicating a receiving node of the message to determine an occupation mode of the first node occupying the channel according to the spatial multiplexing indication information, and when the first node occupies the channel through the spatial multiplexing mode, indicating the receiving node of the message to occupy the channel through a competition mode and then sending a response message to the first node; and/or the presence of a gas in the gas,

the space multiplexing indication information is used for indicating a non-receiving node for monitoring the channel to determine an occupation mode of the first node for occupying the channel according to the space multiplexing indication information, and when the first node occupies the channel in a space multiplexing mode, indicating the non-receiving node for monitoring the channel to occupy the channel after waiting for the channel to be free.

In a third aspect, a method for transmitting a message is provided, the method comprising:

a first node receives a message sent by a second node, wherein the message sent by the second node comprises spatial multiplexing indication information;

and after determining the channel occupied by the second node in a space multiplexing mode according to the space multiplexing indication information in the message sent by the second node, the first node occupies the channel in a competition mode and sends a response message to the second node through the channel.

In a fourth aspect, a method for transmitting a message is provided, the method comprising:

a first node monitors a message sent by a third node in a channel, wherein the message sent by the third node comprises spatial multiplexing indication information;

and after determining the channel occupied by the third node in a space multiplexing mode according to the space multiplexing indication information in the message sent by the third node, the first node waits for the channel to be occupied after the channel is idle.

In a fifth aspect, there is provided a backoff device, comprising:

a starting unit for starting a backoff counter;

and the processing unit is used for continuing counting the backoff counter or reducing the count value of the backoff counter after determining that the channel corresponding to the started backoff counter is occupied by the second node in a space multiplexing mode and cannot jointly occupy the channel with the second node in the space multiplexing mode.

With reference to the fifth aspect, in a first possible implementation manner of the fifth aspect, the processing unit is further configured to:

determining that no other neighbor nodes except the second node exist in the signal coverage range of the first node; alternatively, the first and second electrodes may be,

determining that no neighbor nodes other than the second node and the receiving node of the first node exist in the signal coverage range of the first node.

With reference to the fifth aspect or the first possible implementation manner of the fifth aspect, in a second possible implementation manner of the fifth aspect, the processing unit decreases the count value of the backoff counter and suspends the backoff counter.

With reference to the fifth aspect or the first possible implementation manner of the fifth aspect, in a third possible implementation manner of the fifth aspect, the processing unit is specifically configured to:

periodically decreasing the count value of the backoff counter during occupation of the channel by the second node.

With reference to the fifth aspect or the first possible implementation manner of the fifth aspect, in a fourth possible implementation manner of the fifth aspect, the processing unit is specifically configured to:

multiplying the current count value of the backoff counter by a coefficient and rounding up, wherein the coefficient is greater than 0 and less than 1;

and taking the rounded value as the current count value of the backoff counter.

With reference to the fifth aspect or the first possible implementation manner of the fifth aspect, in a fifth possible implementation manner of the fifth aspect, the processing unit is specifically configured to:

if the difference value between the current count value of the backoff counter and the threshold is less than 0, taking 0 as the current count value of the backoff counter;

and if the difference value between the current count value of the backoff counter and the threshold is not less than 0, taking the difference value as the current count value of the backoff counter.

With reference to the fifth aspect or the first possible implementation manner of the fifth aspect, in a sixth possible implementation manner of the fifth aspect, the processing unit determines whether the second node occupies the channel in a spatial multiplexing manner according to the following manner:

monitoring a first message sent by the second node to other nodes, wherein the first message comprises spatial multiplexing indication information, and the spatial multiplexing indication information is used for indicating an occupation mode of the second node occupying the channel;

and determining whether the second node occupies the channel in a spatial multiplexing mode according to the spatial multiplexing indication information in the first message.

With reference to the fifth aspect or any one of the first to sixth possible implementation manners of the fifth aspect, in a seventh possible implementation manner of the fifth aspect, the apparatus further includes a sending unit:

the sending unit is configured to send a second message through a channel after the channel is occupied, where the second message includes spatial multiplexing indication information, and the spatial multiplexing indication information is used to indicate an occupation manner in which the first node occupies the channel.

With reference to the seventh possible implementation manner of the fifth aspect, the spatial multiplexing indication information is located in an HE signaling HE-SIG of the message physical header.

With reference to the fifth aspect or any one of the first to the eighth possible implementation manners of the fifth aspect, in a ninth possible implementation manner of the fifth aspect, the apparatus further includes a receiving unit:

the receiving unit is configured to receive a third message sent by a third node, where the third message includes spatial multiplexing indication information;

and after determining a channel occupied by the third node in a space multiplexing mode according to the space multiplexing indication information in the third message, occupying the channel in a competition mode and then sending a response message to the third node through the channel.

In a sixth aspect, there is provided a message transmitting apparatus, comprising:

a determining unit, configured to determine that a channel is being occupied;

a sending unit, configured to send a message through the channel, where the message includes spatial multiplexing indication information, where the spatial multiplexing indication information is used to indicate a receiving node of the message to determine, according to the spatial multiplexing indication information, an occupation mode in which a first node occupies the channel, and when the first node occupies the channel through the spatial multiplexing mode, indicate the receiving node of the message to occupy the channel through a contention mode and then send a response message to the first node; and/or the presence of a gas in the gas,

In a seventh aspect, an apparatus for transmitting a message is provided, the apparatus comprising:

a receiving unit, configured to receive a message sent by a second node, where the message sent by the second node includes spatial multiplexing indication information;

and the sending unit is used for determining a channel occupied by the second node in a space multiplexing mode according to the space multiplexing indication information in the message sent by the second node, then occupying the channel in a competition mode, and sending a response message to the second node through the channel.

In an eighth aspect, there is provided a device for transmitting messages, the device comprising:

the monitoring unit is used for monitoring a message sent by a third node in a channel, wherein the message sent by the third node comprises spatial multiplexing indication information;

and the determining unit is used for determining a channel occupied by the third node in a space multiplexing mode according to the space multiplexing indication information in the message sent by the third node, and then waiting for the channel to be occupied after the channel is idle.

In a ninth aspect, there is provided an apparatus for transmitting messages, the apparatus comprising an interface, a processor, a memory, and a transceiver:

a processor for executing the following processes:

starting a backoff counter;

and after determining that the channel corresponding to the started backoff counter is occupied by the second node in a space multiplexing mode and cannot occupy the channel together with the second node in the space multiplexing mode, continuing counting the backoff counter or reducing the count value of the backoff counter.

With reference to the ninth aspect, in a first possible implementation manner of the ninth aspect, the processor is further configured to:

With reference to the ninth aspect or the first possible implementation manner of the ninth aspect, in a second possible implementation manner of the ninth aspect, the processor decreases the count value of the backoff counter and suspends the backoff counter.

With reference to the ninth aspect or the first possible implementation manner of the ninth aspect, in a third possible implementation manner of the ninth aspect, the processor is specifically configured to:

With reference to the ninth aspect or the first possible implementation manner of the ninth aspect, in a fourth possible implementation manner of the ninth aspect, the processor is specifically configured to:

and taking the rounded value as the current count value of the backoff counter.

With reference to the ninth aspect or the first possible implementation manner of the ninth aspect, in a fifth possible implementation manner of the ninth aspect, the processor is specifically configured to:

With reference to the ninth aspect or the first possible implementation manner of the ninth aspect, in a sixth possible implementation manner of the ninth aspect, the processor determines whether the second node occupies the channel in a spatial multiplexing manner according to the following manner:

With reference to the ninth aspect or any one of the first to sixth possible implementation manners of the ninth aspect, in a seventh possible implementation manner of the ninth aspect, the processor is further configured to:

and after occupying the channel, sending a second message through the channel, wherein the second message comprises spatial multiplexing indication information, and the spatial multiplexing indication information is used for indicating an occupation mode of the first node occupying the channel.

With reference to the seventh possible implementation manner of the ninth aspect, in an eighth possible implementation manner of the ninth aspect, the spatial multiplexing indication information is located in an HE signaling HE-SIG of the physical header of the message.

With reference to the ninth aspect or any one of the first to the eighth possible implementation manners of the ninth aspect, in a ninth possible implementation manner of the ninth aspect, the processor is further configured to:

receiving a third message sent by a third node, wherein the third message comprises spatial multiplexing indication information;

In a tenth aspect, there is provided a device for transmitting messages, the device comprising an interface, a processor, a memory and a transceiver:

a processor for executing the following processes:

determining that a channel is being occupied;

sending a message through the channel, wherein the message comprises spatial multiplexing indication information, the spatial multiplexing indication information is used for indicating a receiving node of the message to determine an occupation mode of a first node occupying the channel according to the spatial multiplexing indication information, and when the first node occupies the channel through the spatial multiplexing mode, indicating the receiving node of the message to occupy the channel through a competition mode and then sending a response message to the first node; and/or the presence of a gas in the gas,

In an eleventh aspect, there is provided a device for transmitting messages, the device comprising an interface, a processor, a memory, and a transceiver:

a processor for executing the following processes:

receiving a message sent by a second node, wherein the message sent by the second node comprises spatial multiplexing indication information;

and after determining a channel occupied by the second node in a space multiplexing mode according to the space multiplexing indication information in the message sent by the second node, occupying the channel in a competition mode, and sending a response message to the second node through the channel.

In a twelfth aspect, there is provided a device for transmitting messages, the device comprising an interface, a processor, a memory, and a transceiver:

a processor for executing the following processes:

intercepting a message sent by a third node in a channel, wherein the message sent by the third node comprises spatial multiplexing indication information;

and after determining the channel occupied by the third node in a space multiplexing mode according to the space multiplexing indication information in the message sent by the third node, waiting for the channel to be occupied after the channel is idle.

According to the method and the device provided by the embodiment of the invention, after the first node determines that the channel corresponding to the started backoff counter is occupied by the second node in a space multiplexing mode and cannot occupy the channel with the second node in the space multiplexing mode, the counting of the backoff counter is continued or the count value of the backoff counter is reduced instead of suspending the backoff counter, so that the backoff time required by the first node in executing the backoff process is reduced, the opportunity that the first node occupies the channel is improved, and the utilization rate of the channel is improved.

Drawings

FIG. 1 is a schematic diagram of a multi-node distribution according to an embodiment of the present invention;

fig. 2 is a schematic diagram of a multi-node transmission according to an embodiment of the present invention;

fig. 3 is a schematic diagram of a message structure according to an embodiment of the present invention;

fig. 4 is a schematic flowchart of a back-off method according to an embodiment of the present invention;

fig. 5 is a schematic flow chart of a method for transmitting a message according to an embodiment of the present invention;

fig. 6 is a schematic flowchart of a method for transmitting a message according to an embodiment of the present invention;

fig. 7 is a flowchart illustrating a method for transmitting a message according to an embodiment of the present invention;

fig. 8 is a schematic structural diagram of an escape apparatus according to an embodiment of the present invention;

fig. 9 is a schematic structural diagram of a message transmission apparatus according to an embodiment of the present invention;

fig. 10 is a schematic structural diagram of a message transmission apparatus according to an embodiment of the present invention;

fig. 11 is a schematic structural diagram of a message transmission apparatus according to an embodiment of the present invention;

fig. 12 is a schematic structural diagram of another backoff device according to an embodiment of the present invention;

fig. 13 is a schematic structural diagram of another message transmission apparatus according to an embodiment of the present invention;

fig. 14 is a schematic structural diagram of another message transmission apparatus according to an embodiment of the present invention;

fig. 15 is a schematic structural diagram of another message transmission apparatus according to an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention clearer, the present invention will be described in further detail with reference to the accompanying drawings, and it is apparent that the described embodiments are only a part of the embodiments of the present invention, not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

In the embodiment of the invention, before the nodes participating in channel competition prepare to send messages, a number is randomly generated as a counting value in a backoff counter, and then the nodes start to monitor the channel and execute the backoff process. When a node contends for a channel, it starts to send a message in the channel. After the node determines that the channel is occupied in the backoff process, in order to determine whether the node can jointly occupy the channel with the node occupying the channel in a spatial multiplexing mode, the node also listens to a message sent by the node occupying the channel to other nodes so as to determine whether the message is sent in parallel with the message sent by the node.

In the embodiment of the present invention, a format of a message sent by a node may be as shown in fig. 3, fig. 3 is a schematic diagram of a message structure provided in the embodiment of the present invention, fig. 3 includes a Physical header Field such as a legacy preamble (legacy preamble), a Repeated legacy signaling (Repeated L access Signal Field, R-L-SIG), and a HE preamble (High Efficiency preamble), and a PSDU (Physical layer Service Data Unit) carried by a frame, fig. 3 illustrates that the HE preamble includes a HE signaling (High Efficiency Signal, HE-SIG), a HE Short Training sequence (HE-Short Training Field, HE-STF), and a HE long Training sequence (HE-long Training sequence L on Training, HE-L TF).

Based on the above discussion, as shown in fig. 4, a schematic flow chart of a backoff method provided in the embodiment of the present invention is shown. The first node in fig. 4 may be an AP, STA, or other device, and the second node may be an AP, STA, or other device.

As shown in fig. 4, the method specifically includes the following steps:

step 401: the first node starts a backoff counter;

step 402: and after the first node determines that the channel corresponding to the started backoff counter is occupied by the second node in a space multiplexing mode and cannot occupy the channel together with the second node in the space multiplexing mode, continuing counting the backoff counter or reducing the count value of the backoff counter.

In step 401, before the first node starts the backoff counter, a random number may be generated as a count value of the backoff counter. After the first node starts the backoff counter, it starts listening to the channel and counting.

For example, the first node decrements the count value in the backoff counter by one when it determines that the channel is in an idle state for one time slot. The length of a timeslot is generally predetermined in the wlan standard.

In step 402, after occupying a channel, a first node may send a second message through the channel, where the second message includes spatial multiplexing indication information, and the spatial multiplexing indication information is used to indicate an occupation manner in which the first node occupies the channel, that is, the spatial multiplexing indication information may indicate whether the first node occupies the channel in a spatial multiplexing manner or occupies the channel in a contention manner. After the other nodes listen to the second message sent by the first node, the occupation mode of the first node for occupying the channel can be determined according to the listened spatial multiplexing indication information in the second message sent by the first node.

For example, the spatial multiplexing indication information may be a bit in a physical header of the message, where the bit is predetermined. For example, when the value of the bit is 0, it indicates that the node occupying the channel is the channel occupied by performing the backoff procedure; when the value of the bit is 1, the node occupying the channel is the channel occupied by the space multiplexing mode. It should be noted that the spatial multiplexing indication information may also be represented by a plurality of bits, which is not limited in the embodiment of the present invention.

Preferably, the spatial multiplexing indication information is located in HE signaling HE-SIG of the physical header of the message. The spatial multiplexing indication information may be composed of any one dedicated bit in the HE-SIG or may be composed of multiple bits in combination with other indication information, which is not limited in this embodiment of the present invention.

Since the receiving node needs to return a response message to the sending node after receiving the message sent by the sending node, in order to avoid that the node occupying the channel in the spatial multiplexing manner interferes with the sending node (the node occupying the channel in the contention manner) receiving the response message sent by the receiving node, the node occupying the channel in the spatial multiplexing manner needs to end the message being sent before the node occupying the channel in the contention manner ends occupying the channel, or end the message being sent simultaneously with the node occupying the channel in the contention manner.

A receiving node of a node occupying a channel in a spatial multiplexing manner may transmit a response message simultaneously with a receiving node of a node occupying a channel in a contention manner, thereby causing mutual interference. In the embodiment of the present invention, by carrying the spatial multiplexing indication information in the message sent by the sending node, the receiving node can determine whether the corresponding sending node is a channel occupied by a spatial multiplexing mode or a contention mode according to the spatial multiplexing indication information in the received message. If the receiving node determines that the sending node occupies the channel in a space multiplexing mode, the response message is not replied immediately after the message is received, but the response message is replied through the contended channel after the contended channel is contended in a contention mode. It should be noted that, in the embodiment of the present invention, after the receiving node determines that the sending node occupies the channel in the spatial multiplexing manner, the receiving node may also reply the response message in other manners, which is not described herein again.

Correspondingly, with reference to the above description, the first node receives a third message sent by a third node, where the third message sent by the third node includes spatial multiplexing indication information; after the first node determines a channel occupied by the third node in a space multiplexing mode according to space multiplexing indication information in a third message sent by the third node, the first node sends a response message to the third node through the channel after occupying the channel in a competition mode.

It should be noted that, the spatial multiplexing indication information may also indicate that, when determining that the sensed message is transmitted in a spatial multiplexing manner, the node that senses the message does not use the spatial multiplexing manner to transmit the message in parallel with the node that occupies the channel in the spatial multiplexing manner, but waits for the channel to be occupied after being idle. Of course, the present invention is not limited thereto.

In the embodiment of the invention, if the first node competes for the channel, the message is sent through the channel which competes. If the first node does not compete to the channel, the first node can judge whether a second node occupying the channel occupies the channel together in a space multiplexing mode, if so, directly determine that the channel cannot be occupied together in the space multiplexing mode, if not, judge whether the second node occupying the channel and the second node occupying the channel can occupy the channel together in the space multiplexing mode, and if the second node occupying the channel and the second node occupying the channel can occupy the channel together in the space multiplexing mode, send a message through the channel; the first node may not determine whether the second node occupying the channel occupies the channel together in the spatial multiplexing manner, but always determines whether the first node and the second node occupying the channel can occupy the channel together in the spatial multiplexing manner, and if the first node and the second node occupying the channel can occupy the channel together in the spatial multiplexing manner, the first node sends the message through the channel.

If the first node determines that the channel is occupied by the second node in a spatial multiplexing mode and determines that the channel cannot be jointly occupied by the first node and the second node in the spatial multiplexing mode, the backoff counter may not be suspended or the count value of the backoff counter may be reduced.

With reference to the above description, the first node may determine whether the second node occupies the channel in a spatial multiplexing manner according to the following manner:

the first node monitors a first message sent by the second node to other nodes, wherein the first message sent by the second node to other nodes comprises spatial multiplexing indication information, and the spatial multiplexing indication information is used for indicating an occupation mode of the second node for occupying the channel; and the first node determines whether the second node occupies the channel in a spatial multiplexing mode according to spatial multiplexing indication information in a first message sent by the second node.

Before the first node does not suspend the backoff counter or reduces the count value of the backoff counter, it may also be required to determine whether to suspend the backoff counter or reduce the count value of the backoff counter according to the number of its neighbor nodes.

Preferably, before the first node does not suspend the backoff counter or reduces the count value of the backoff counter, it may further need to satisfy any one of the following conditions:

the first condition is as follows: the first node determines that no other neighboring nodes except the second node are within the signal coverage of the first node.

And a second condition: the first node determines that no other neighbor nodes except the second node and the receiving node of the first node exist in the signal coverage range of the first node.

Under the condition, the receiving node of the first node establishes connection with the first node, and the first node is a message sender, so the receiving node of the first node does not compete for a channel to send messages to other nodes, and can exclude the messages.

If the first node does not pause the backoff counter, the backoff counter continues counting down, and if the backoff counter counts to 0 before the channel is idle, the backoff counter keeps the state of counting to 0 all the time and occupies the channel after the channel is idle.

The purpose of the first node to reduce the count value of the backoff counter is to reduce the backoff time required by the first node to perform the backoff process when the channel is idle, thereby improving the chance of channel contention.

Preferably, the first node decreases the count value of the backoff counter and suspends the backoff counter.

The first node may decrement the count value of the backoff counter in a number of ways, each described below.

A first possible implementation:

the first node multiplies the current count value of the backoff counter by a coefficient and rounds the count value, wherein the coefficient is greater than 0 and less than 1; and the first node takes the rounded value as the current count value of the backoff counter.

For example, the current count value of the backoff counter is a, a ≧ 0, the first node multiplies a by a coefficient B, 0< B <1, obtains C as a × B, rounds C, and replaces a with C.

It should be noted that, when rounding is performed, rounding may be performed downward or upward, and this is not limited in the embodiment of the present invention.

A second possible implementation:

For example, the current count value of the backoff counter is A, where A ≧ 0. The first node subtracts a from a by a threshold B to obtain C-a-B. And then judging whether C is smaller than 0, if C is smaller than 0, taking 0 as the current count value of the backoff counter, otherwise, taking C as the current count value of the backoff counter, namely replacing A with C. At this time, the backoff counter of the first node performs a backoff process from C when the channel is idle.

It should be noted that the threshold is a positive integer, and the threshold may be randomly generated each time, may be predetermined, or may be determined according to the current count value of the backoff counter, which is not limited in the embodiment of the present invention.

Preferably, the threshold is determined according to a time length of the second node occupying the channel in the spatial multiplexing mode, specifically, the time length of the second node occupying the channel in the spatial multiplexing mode is divided by a reduction coefficient to obtain the threshold, and the reduction coefficient is greater than 1.

For example, the length of time that the second node occupies the channel by spatial multiplexing is 200 μ sec, and the reduction coefficient is 20, then the obtained threshold is 200/20, which is 10.

A third possible implementation:

For example, the first node subtracts a fixed value or a random value from the current count value of the backoff counter every cycle, and when the current count value of the backoff counter is less than 0, the first node takes 0 as the current count value of the backoff counter.

And when determining that the channel is idle, the first node judges whether the current count value of the backoff counter is 0, if so, the first node occupies the channel, otherwise, the first node executes the backoff process according to the current count value of the backoff counter.

In the above scheme, after the first node determines that the channel corresponding to the started backoff counter is occupied by the second node in the spatial multiplexing mode and cannot occupy the channel with the second node in the spatial multiplexing mode, the backoff counter is not suspended, but counting of the backoff counter is continued or the count value of the backoff counter is reduced, so that the backoff time required by the first node in executing the backoff process is reduced, the opportunity that the first node occupies the channel is improved, and the utilization rate of the channel is improved.

The nodes can effectively improve the utilization efficiency of the channel by jointly occupying the channel in a spatial multiplexing mode, but the problem of hidden nodes can be easily caused, so that the collision probability is improved, and therefore, preferably, when one node uses the spatial multiplexing mode to transmit messages in parallel with one node transmitting the messages, the nodes around the node can know that the messages are transmitted in the spatial multiplexing mode, and further use of the spatial multiplexing mode to transmit in parallel with the node is avoided.

Based on the above discussion, as shown in fig. 5, a flow chart of a method for transmitting a message according to an embodiment of the present invention is provided. The first node in fig. 5 may be an AP, STA, or the like.

As shown in fig. 5, the method specifically includes the following steps:

step 501: a first node determines that the first node is occupying a channel;

step 502: the first node sends a message through the channel, wherein the message comprises spatial multiplexing indication information; the spatial multiplexing indication information is used for indicating a receiving node of the message to determine an occupation mode of the first node occupying the channel according to the spatial multiplexing indication information, and when the first node occupies the channel through the spatial multiplexing mode, indicating the receiving node of the message to occupy the channel through a competition mode and then sending a response message to the first node; and/or the spatial multiplexing indication information is used for indicating a non-receiving node which listens to the channel to determine an occupation mode of the first node occupying the channel according to the spatial multiplexing indication information, and when the first node occupies the channel in a spatial multiplexing mode, indicating the non-receiving node which listens to the channel to occupy the channel after waiting for the channel to be free.

In step 501, the first node may occupy the channel in a contention mode or a spatial multiplexing mode.

It should be noted that how the first node occupies the channel specifically is not limited in the embodiment of the present invention.

In step 502, the receiving node is a node corresponding to the destination address carried in the message, and the corresponding non-receiving node is a node not corresponding to the destination address carried in the message. Since the node will listen to the channel, the received message may not be sent to itself.

Therefore, after the first node sends the message through the channel, the node receiving the message may be a receiving node of the message sent by the first node; but also other nodes that are listening to the channel, i.e. non-receiving nodes.

The spatial multiplexing indication information in the message sent by the first node may be a bit in a physical header of the message, where the bit is pre-agreed. For example, when the value of the bit is 0, it indicates that the node occupying the channel is the channel occupied by performing the backoff procedure; when the value of the bit is 1, the node occupying the channel is the channel occupied by the space multiplexing mode.

It should be noted that the spatial multiplexing indication information may also be represented by a plurality of bits, which is not limited in the embodiment of the present invention.

And if the receiving node of the message sent by the first node determines that the first node occupies the channel in a competition mode according to the spatial multiplexing indication information, the receiving node sends a response message to the first node according to a mode specified in the standard of the existing wireless local area network. For example, after the first node finishes message transmission, a response message is transmitted to the first node through the channel.

It should be noted that, when a receiving node of a message sent by a first node determines that the first node occupies the channel in a contention manner, a response message may also be sent to the first node in other manners, which is not limited in this embodiment of the present invention.

And if the receiving node of the message sent by the first node determines that the first node occupies the channel in a space multiplexing mode according to the space multiplexing indication information, the receiving node occupies the channel in a competition mode and then sends a response message to the first node.

And when the non-receiving node for intercepting the channel determines that the first node occupies the channel in a contention mode according to the spatial multiplexing indication information, whether the channel can be jointly occupied with the first node or not may be determined, and if the channel can be jointly occupied with the first node in a spatial multiplexing mode, the channel can be jointly occupied with the first node by the non-receiving node.

The first node may listen to the channel or receive a message sent by the second node while the channel is unoccupied.

When receiving the message sent by the second node, the first node determines how to send the response message to the second node according to the occupation mode of the channel occupied by the second node. Specifically, a first node receives a message sent by a second node, where the message sent by the second node includes spatial multiplexing indication information; and after determining the channel occupied by the second node in a space multiplexing mode according to the space multiplexing indication information in the message sent by the second node, the first node occupies the channel in a competition mode and sends a response message to the second node through the channel. And after determining the channel occupied by the second node in a competition mode according to the spatial multiplexing indication information in the message sent by the second node, the first node sends a response message to the first node in a mode specified in the standard of the existing wireless local area network.

When the first node monitors the channel, whether the first node and a third node occupy the channel together in a space multiplexing mode is determined according to the occupation mode of the third node occupying the channel. Specifically, a first node listens to a message sent by a third node in the channel, where the message sent by the third node includes spatial multiplexing indication information; and after determining the channel occupied by the third node in the space multiplexing mode according to the space multiplexing indication information in the message sent by the third node, the first node determines not to jointly occupy the channel with the third node in the space multiplexing mode, but to occupy the channel after waiting for the channel to be idle. If the first node determines the channel occupied by the third node in the contention mode according to the spatial multiplexing indication information in the message sent by the third node, it may be determined whether the first node can occupy the channel occupied by the third node in the contention mode, and after determining the channel occupied by the third node in the contention mode, the first node sends the message through the channel.

Based on the above discussion, as shown in fig. 6, a schematic flow chart of a method for transmitting a message according to an embodiment of the present invention is provided. The first node in fig. 6 may be an AP, STA, or the like.

As shown in fig. 6, the method specifically includes the following steps:

step 601: a first node receives a message sent by a second node, wherein the message sent by the second node comprises spatial multiplexing indication information;

step 602: and after determining the channel occupied by the second node in a space multiplexing mode according to the space multiplexing indication information in the message sent by the second node, the first node occupies the channel in a competition mode and sends a response message to the second node through the channel.

It should be noted that, specific contents of step 601 and step 602 may refer to descriptions in fig. 4 and fig. 5, and are not described again here.

Based on the above discussion, as shown in fig. 7, a flow chart of a method for transmitting a message according to an embodiment of the present invention is provided. The first node in fig. 7 may be an AP, STA, or the like.

As shown in fig. 7, the method specifically includes the following steps:

step 701: a first node monitors a message sent by a third node in a channel, wherein the message sent by the third node comprises spatial multiplexing indication information;

step 702: and after determining the channel occupied by the third node in a space multiplexing mode according to the space multiplexing indication information in the message sent by the third node, the first node waits for the channel to be occupied after the channel is idle.

It should be noted that, for details of step 701 and step 702, reference may be made to descriptions in fig. 4 and fig. 5, which are not described herein again.

In the above scheme, the message sent by the first node includes spatial multiplexing indication information for indicating the manner in which the first node occupies the channel, so that after other nodes receive or listen to the message sent by the first node, it can be determined whether the first node occupies the channel in the spatial multiplexing manner or occupies the channel in the contention manner. After other nodes determine that the first node is a channel occupied by a space multiplexing mode, a response message is not immediately sent to the first node; and/or the first node and the second node do not occupy the channel together in a space multiplexing mode, so that the probability of mutual interference of messages sent between the nodes is reduced, and the utilization rate of the channel is improved.

For the above method flow, an embodiment of the present invention further provides a backoff device, and specific contents of the device may be implemented with reference to the above method, which is not described herein again.

As shown in fig. 8, an embodiment of the invention provides a schematic structural diagram of a backoff device.

The apparatus may be used to perform the method shown in fig. 4.

Referring to fig. 8, the apparatus includes:

an activation unit 801 for activating a backoff counter;

the processing unit 802 is configured to continue to count the backoff counter or reduce the count value of the backoff counter after determining that the channel corresponding to the started backoff counter is occupied by the second node in a spatial multiplexing manner and cannot jointly occupy the channel with the second node in the spatial multiplexing manner.

Preferably, the processing unit 802 is further configured to:

Preferably, the processing unit 802 decreases the count value of the backoff counter and suspends the backoff counter.

Preferably, the processing unit 802 is specifically configured to:

and taking the rounded value as the current count value of the backoff counter.

Preferably, the processing unit 802 is specifically configured to:

Preferably, the processing unit 802 determines whether the second node occupies the channel in a spatial multiplexing manner according to the following manners:

monitoring a first message sent by the second node to other nodes, wherein the first message sent by the second node to other nodes comprises spatial multiplexing indication information, and the spatial multiplexing indication information is used for indicating an occupation mode of the second node for occupying the channel;

and determining whether the second node occupies the channel in a spatial multiplexing mode according to spatial multiplexing indication information in a first message sent by the second node.

Preferably, the apparatus further comprises a sending unit 803:

the sending unit 803 is configured to send a second message through a channel after the channel is occupied, where the second message includes spatial multiplexing indication information, and the spatial multiplexing indication information is used to indicate an occupation manner in which a first node occupies the channel.

Preferably, the spatial multiplexing indication information is located in an HE signaling HE-SIG of the physical header of the message.

Preferably, the apparatus further comprises a receiving unit 804:

the receiving unit 804 is configured to receive a third message sent by a third node, where the third message sent by the third node includes spatial multiplexing indication information;

after determining a channel occupied by the third node in a space multiplexing mode according to space multiplexing indication information in a third message sent by the third node, occupying the channel in a competition mode and then sending a response message to the third node through the channel.

For the above method flow, an embodiment of the present invention further provides a message transmission apparatus, and specific contents of the apparatus may be implemented by referring to the above method, which is not described herein again.

As shown in fig. 9, an embodiment of the present invention provides a schematic structural diagram of a message transmission apparatus.

The apparatus may be used to perform the method shown in fig. 5.

Referring to fig. 9, the apparatus includes:

a determining unit 901, configured to determine that the first node is occupying a channel;

a sending unit 902, configured to send a message through the channel, where the message includes spatial multiplexing indication information;

the spatial multiplexing indication information is used for indicating a receiving node of the message to determine an occupation mode of a first node occupying the channel according to the spatial multiplexing indication information, and when the first node occupies the channel in a spatial multiplexing mode, indicating the receiving node of the message to occupy the channel in a competition mode and then sending a response message to the first node; and/or the presence of a gas in the gas,

As shown in fig. 10, an embodiment of the present invention provides a schematic structural diagram of a message transmission apparatus.

The apparatus may be used to perform the method shown in fig. 6.

Referring to fig. 10, the apparatus includes:

a receiving unit 1001, configured to receive a message sent by a second node, where the message sent by the second node includes spatial multiplexing indication information;

a sending unit 1002, configured to determine, according to spatial multiplexing indication information in a message sent by the second node, a channel occupied by the second node in a spatial multiplexing manner, then occupy the channel in a contention manner, and send a response message to the second node through the channel.

As shown in fig. 11, an embodiment of the present invention provides a schematic structural diagram of a message transmission apparatus.

The apparatus may be used to perform the method shown in fig. 7.

Referring to fig. 11, the apparatus includes:

an intercepting unit 1101, configured to intercept a message sent by a third node in a channel, where the message sent by the third node includes spatial multiplexing indication information;

a determining unit 1102, configured to determine, according to the spatial multiplexing indication information in the message sent by the third node, a channel occupied by the third node in a spatial multiplexing manner, and then wait for the channel to be occupied after the channel is idle.

Based on the same concept, referring to fig. 12, a backoff device 1200 is provided for an embodiment of the present invention. The apparatus may be used to perform the method shown in fig. 4. The apparatus may include: an interface 1201, a processor 1202, a memory 1203, and a transceiver 1204. The processor 1202 is configured to control the operation of the transmitting apparatus 1200; the memory 1203 may include both read-only memory and random access memory for providing instructions and data to the processor 1202. A portion of the memory 1203 may also include non-volatile row random access memory (NVRAM). The various components of the transmitting device 1200 are coupled together by a bus system, where the bus system 1209 includes a power bus, a control bus, and a status signal bus in addition to a data bus. For clarity of illustration, however, the various buses are designated as the bus system 1209 in the figure.

A processor 1202 configured to perform the following processes:

starting a backoff counter;

Preferably, the processor 1202 is further configured to:

Preferably, the processor 1202 decrements the back-off counter count value and pauses the back-off counter.

Preferably, the processor 1202 is specifically configured to:

and taking the rounded value as the current count value of the backoff counter.

Preferably, the processor 1202 is specifically configured to:

Preferably, the processor 1202 determines whether the second node occupies the channel in a spatial multiplexing manner according to the following manner:

Preferably, the processor 1202 is further configured to:

receiving a third message sent by a third node, wherein the third message sent by the third node comprises spatial multiplexing indication information;

The backoff method disclosed in the embodiments of the present invention may be applied to the processor 1202, or implemented by the processor 1202. In implementation, the steps of the control plane processing flow may be performed by instructions in the form of hardware, integrated logic circuits, or software in the processor 1202. The processor 1202 may be a general purpose processor, a digital signal processor, an application specific integrated circuit, a field programmable gate array or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or the like that implement or perform the methods, steps, and logic blocks disclosed in embodiments of the present invention. A general purpose processor may be a microprocessor or any conventional processor or the like. The steps of a method disclosed in connection with the embodiments of the present invention may be directly implemented by a hardware processor, or may be implemented by a combination of hardware and software modules in the processor. The software module may be located in ram, flash memory, rom, prom, or eprom, registers, etc. storage media as is well known in the art. The storage medium is located in the memory 1203, and the processor 1202 reads the information in the memory 1203, and completes the steps of a backoff method in conjunction with its hardware.

Based on the same concept, referring to fig. 13, a message transmission apparatus 1300 is provided for the embodiment of the present invention. The apparatus may be used to perform the method shown in fig. 5. The apparatus may include: an interface 1301, a processor 1302, a memory 1303 and a transceiver 1304. The processor 1302 is configured to control the operation of the transmitting apparatus 1300; memory 1303 may include read-only memory and random access memory for providing instructions and data to processor 1302. A portion of the memory 1303 may also include non-volatile row random access memory (NVRAM). The various components of the transmitting device 1300 are coupled together by a bus system 1309 that includes a power bus, a control bus, and a status signal bus in addition to a data bus. For clarity of illustration, however, the various buses are designated in the figure as the bus system 1309.

A processor 1302, configured to perform the following process:

determining that a channel is being occupied;

sending a message through the channel, wherein the message comprises spatial multiplexing indication information;

Based on the same conception, referring to fig. 14, a message transmission apparatus 1400 is provided for the embodiment of the present invention. The apparatus may be used to perform the method shown in fig. 6. The apparatus may include: an interface 1401, a processor 1402, a memory 1403, and a transceiver 1404. The processor 1402 is configured to control the operation of the transmitting apparatus 1400; memory 1403 may include both read-only memory and random access memory for providing instructions and data to processor 1402. A portion of memory 1403 may also include non-volatile row random access memory (NVRAM). The various components of the transmitting device 1400 are coupled together by a bus system, wherein the bus system 1409 includes a power bus, a control bus, and a status signal bus in addition to a data bus. For clarity of illustration, however, the various buses are designated in the figure as the bus system 1409.

A processor 1402 configured to perform the following processes:

Based on the same concept, referring to fig. 15, a receiving apparatus 1500 according to an embodiment of the present invention is provided. The apparatus may be used to perform the method shown in fig. 7. The apparatus may include: an interface 1501, a processor 1502, a memory 1503, and a transceiver 1504. The processor 1502 is configured to control the operation of the receiving apparatus 1500; memory 1503 may include both read-only memory and random access memory for providing instructions and data to processor 1502. A portion of the memory 1503 may also include non-volatile row random access memory (NVRAM). The various components of the receiving device 1500 are coupled together by a bus system, where the bus system 1509 includes a power bus, a control bus, and a status signal bus in addition to a data bus. For clarity of illustration, however, the various buses are labeled in the figure as the bus system 1509.

A processor 1502 configured to execute the following processes:

The method for transmitting messages disclosed by the embodiment of the invention can be applied to the processor 1502, or can be implemented by the processor 1502. In implementation, the steps of the control plane processing flow may be performed by instructions in the form of hardware, integrated logic circuits, or software in the processor 1502. The processor 1502 may be a general purpose processor, a digital signal processor, an application specific integrated circuit, a field programmable gate array or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or the like that implement or perform the methods, steps, and logic blocks disclosed in embodiments of the present invention. A general purpose processor may be a microprocessor or any conventional processor or the like. The steps of a method disclosed in connection with the embodiments of the present invention may be directly implemented by a hardware processor, or may be implemented by a combination of hardware and software modules in the processor. The software module may be located in ram, flash memory, rom, prom, or eprom, registers, etc. storage media as is well known in the art. The storage medium is located in the memory 1503, and the processor 1502 reads the information in the memory 1503 to implement the steps of a method for transmitting messages in conjunction with its hardware.

As will be appreciated by one skilled in the art, embodiments of the present invention may be provided as a method, system, or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product embodied on one or more computer-usable storage channels (including, but not limited to, disk storage, optical storage, and the like) having computer-usable program code embodied therein.

The present invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.

Claims

1. A back-off method, comprising:

the first node starts a backoff counter;

and after the first node determines that the channel corresponding to the started backoff counter is occupied by the second node in a space multiplexing mode and cannot occupy the channel together with the second node in the space multiplexing mode, continuing counting of the backoff counter or reducing the count value of the backoff counter.

2. The method of claim 1, wherein before the first node does not pause the backoff counter or decreases the count value of the backoff counter, further comprising:

3. The method according to any of claims 1 to 2, wherein the first node decrements the back-off counter count value and pauses the back-off counter.

4. The method according to any of claims 1 to 2, wherein the first node decrements the back-off counter value comprising:

5. The method according to any of claims 1 to 2, wherein the first node decrements the back-off counter value comprising:

6. The method according to any of claims 1 to 2, wherein the first node decrements the back-off counter value comprising:

7. The method according to any of claims 1 to 2, wherein the first node determines whether the second node occupies the channel by spatial multiplexing according to:

8. The method according to any one of claims 1 to 2, characterized in that the method further comprises:

9. The method of claim 8, wherein the spatial multiplexing indication information is located in an HE signaling HE-SIG of the message physical header.

10. The method according to any one of claims 1 to 2, characterized in that the method further comprises:

11. A backoff device applied to a first node, the device comprising:

a starting unit for starting a backoff counter;

12. The apparatus of claim 11, wherein the processing unit is further configured to:

determining that no neighbor nodes other than the second node exist in the signal coverage range of the first node; alternatively, the first and second electrodes may be,

13. The apparatus according to any one of claims 11 to 12, wherein the processing unit decreases the count value of the backoff counter and suspends the backoff counter.

14. The apparatus according to any one of claims 11 to 12, wherein the processing unit is specifically configured to:

15. The apparatus according to any one of claims 11 to 12, wherein the processing unit is specifically configured to:

and taking the rounded value as the current count value of the backoff counter.

16. The apparatus according to any one of claims 11 to 12, wherein the processing unit is specifically configured to:

17. The apparatus according to any of claims 11 to 12, wherein the processing unit determines whether the second node occupies the channel by spatial multiplexing according to:

18. The apparatus according to any one of claims 11 to 12, characterized in that the apparatus further comprises a transmitting unit:

the sending unit is configured to send a second message through a channel after the channel is occupied, where the second message includes spatial multiplexing indication information, and the spatial multiplexing indication information is used to indicate an occupation manner in which a first node occupies the channel.

19. The apparatus of claim 18, wherein the spatial multiplexing indication information is located in an HE signaling HE-SIG of the message physical header.

20. The apparatus according to any one of claims 11 to 12, characterized in that the apparatus further comprises a receiving unit:

21. A backoff device for use in a first node, the device comprising an interface, a processor, a memory, and a transceiver:

a processor for executing the following processes:

starting a backoff counter;

22. The apparatus of claim 21, wherein the processor is further configured to:

23. The apparatus according to any of claims 21 to 22, wherein the processor decreases the count value of the backoff counter and pauses the backoff counter.

24. The apparatus according to any of claims 21 to 22, wherein the processor is specifically configured to:

25. The apparatus according to any of claims 21 to 22, wherein the processor is specifically configured to:

and taking the rounded value as the current count value of the backoff counter.

26. The apparatus according to any of claims 21 to 22, wherein the processor is specifically configured to:

27. The apparatus of any of claims 21 to 22, wherein the processor determines whether the second node occupies the channel by spatial multiplexing according to:

28. The apparatus of any one of claims 21 to 22, wherein the processor is further configured to:

29. The apparatus of claim 28, wherein the spatial multiplexing indication information is located in an HE signaling HE-SIG of the message physical header.

30. The apparatus of any one of claims 21 to 22, wherein the processor is further configured to: