WO2014206102A1

WO2014206102A1 - Media access method, service access point, station, and system

Info

Publication number: WO2014206102A1
Application number: PCT/CN2014/072437
Authority: WO
Inventors: 李靖; 李云波; 伍天宇
Original assignee: 华为技术有限公司
Priority date: 2013-06-27
Filing date: 2014-02-24
Publication date: 2014-12-31
Also published as: CN104254136B; CN104254136A

Abstract

Disclosed are a media access method, a service access point, a station, and a system, which belong to the field of wireless communications. The method comprises: starting an OFDMA phase based on a CSMA/CA mechanism, and sending an OFDMA phase start indication to an OFDMA station STA; an AP receiving a contention-based access request sent by at least one OFDMA STA that initiates OFDMA access contention within the duration of the OFDMA phase; and configuring a channel resource for the at least one OFDMA STA according to the contention-based access request, and notifying the at least one OFDMA STA of configuration information of the channel resource, so that the at least one OFDMA STA performs media access according to the configuration information of the channel resource. In the present invention, after an OFDMA multiple access contention-based access mechanism is introduced, multiple access contention-based access to an OFDMA wireless medium resource is implemented in a case where a CSMA/CA mechanism and an OFDMA mechanism coexist, thereby enhancing the access efficiency of a system.

Description

Description Media access methods, service access points, sites and systems

This application is submitted to the Chinese Patent Office on June 27, 201, and the application number is

201 310263311. 2. The priority of the invention is the priority of the Chinese patent application, the disclosure of which is incorporated herein by reference.

Technical field

The present invention relates to the field of wireless communications, and in particular, to a medium access method, a service access point, a station, and a system. Background technique

With the increasing number of mobile terminals, wireless communication applications are becoming more and more widespread, and the requirements for wireless technologies are becoming higher and higher. In a WLAN (Wireless Local Access Network) system, there are multiple STAs (Stations) and multiple APs (Access Point), when multiple STAs request to communicate with the same AP at the same time. At this time, conflicts arise, and media access techniques are introduced to resolve such conflicts.

In the WLAN system, the CSMA/CA (Carrier Sense Multiple Access/Collision Avoidance) mechanism is used to implement the competitive access of the wireless medium to solve the problem that multiple STAs simultaneously require the same The conflict that occurs when the AP communicates. In the CSMA/CA mechanism, when any STA in the system wants to send information, it first needs to listen to whether the channel is idle. After detecting that the channel is in an idle state, the STA needs to wait for one frame time, and then randomly selects a backoff time. If the channel is not occupied after detecting the backoff time, the information is sent, if the channel is detected to be occupied during the backoff time. And continuing to listen to whether the channel is in an idle state. When detecting that the channel is in an idle state, the remaining backoff time is used as a new backoff time. If the channel is not occupied after detecting the new backoff time, the information is sent. If it is detected that the channel is occupied in the new backoff time, it continues to listen to whether the channel is in an idle state, and so on, until the backoff time is 0, the backoff time is reselected, and the next round of contention access is started.

In the process of implementing the present invention, the inventors have found that the prior art has at least the following problems: In the prior art, when multiple STAs existing in the system need to communicate with the AP, the probability that the STA selects the same backoff time is high, and occurs. The probability of conflict is high, and because one is allowed at a time The STA communicates with the AP, resulting in inefficient access to the system. Summary of the invention

In order to improve the access efficiency of the system, the embodiment of the present invention provides a medium access method, a service access point, a station, and a system, which can reduce the probability of a STA colliding with the UI and improve the access efficiency of the system. . The technical solution is as follows:

The first aspect provides a method for media access, where the method includes:

Initiating an OFDMA (Orthogonal Frequency Division Multiple Access) phase based on the CSMA/CA mechanism, and transmitting an OFDMA phase initiation indication to the OFDMA STA; receiving at least one OFDMA STA that initiates OFDMA access competition within the OFDMA phase duration Sending a competitive access request;

Configuring a channel resource for the at least one OFDMA STA according to the contention access request, and notifying the at least one OFDMA STA of the configuration information of the channel resource, according to the channel resource Configure information for media access.

With reference to the first aspect, in a first possible implementation manner of the first aspect, the performing the OFDMA phase based on the CSMA/CA mechanism includes:

Initiating channel competition based on the CSMA/CA mechanism, starting the OFDMA phase;

Alternatively, the channel contention request sent by the OFDMA STA based on the CSMA/CA mechanism is received, and the OFDMA phase is initiated according to the channel contention request.

With reference to the first possible implementation of the first aspect, in a second possible implementation manner of the first aspect, after the starting the OFDMA phase by using the CSMA/CA mechanism, the method further includes:

Sending a channel reservation indication to all the STAs in the system, where the channel reservation indication carries a NAV (Network Allocation Vector) value, so that the STA that receives the channel reservation indication according to the channel reservation indication The NAV value carried in the update updates the local NAV value. For an OFDMA STA, it is possible to selectively update its NAV value without affecting the subsequent OFDMA access procedure.

With reference to the first aspect, in a third possible implementation manner of the first aspect, the sending, by the OFDMA STA, an OFDMA stage start indication includes:

Transmitting an OFDMA phase start indication including an OFDMA phase duration to an OFDMA STA, In conjunction with the first aspect, in a fourth possible implementation of the first aspect, the receiving is in the

Before the at least one OFDMA STA that initiates the OFDMA access competition within the duration of the OFDMA phase, before the contention request is sent, the method further includes:

Setting a size of a competition window of the OFDMA access competition, and notifying the OFDMA STA of the set size of the competition window of the OFDMA access competition, so that the OFDMA STA is in a size range of the contention window Initiated OFDMA access competition.

In a second aspect, a method for media access is provided, where the method includes:

Receiving an OFDMA phase start indication sent by the service access point AP;

Initiating an OFDMA access competition within the duration of the OFDMA phase, and transmitting a contention access request to the AP;

Receiving, by the AP, configuration information of the channel resource that is notified after the channel resource is configured according to the contention access request, and performing media access according to the configuration information of the channel resource.

With reference to the second aspect, in a first possible implementation manner of the second aspect, before the receiving, by the receiving AP, the OFDMA stage start indication, the method further includes:

The carrier-based multi-point access/collision avoidance CSMA/CA mechanism sends a channel contention request to the AP, so that the AP sends the OFDMA phase start indication after starting the OFDMA phase according to the channel contention request.

With reference to the second aspect, in a second possible implementation manner of the second aspect, the receiving, by the receiving AP, the OFDMA stage startup indication includes:

And receiving, by the AP, an OFDMA phase initiation indication that includes an OFDMA phase duration; before the initiating the OFDMA access competition within the OFDMA phase duration, the method further includes: determining the OFDMA phase duration according to the OFDMA phase startup indication.

With reference to the second aspect, in a third possible implementation manner of the second aspect, before the initiating the OFDMA access competition in the duration of the OFDMA phase, the method further includes:

Receiving a channel reservation indication sent by the AP, where the channel reservation indication carries a NAV value; determining an OFDMA phase duration according to the NAV value carried in the channel reservation indication.

With reference to the second aspect, in a fourth possible implementation manner of the second aspect, before the initiating the OFDMA access competition in the duration of the OFDMA phase, the method further includes:

Determining, according to the notification of the AP, a size of a competition window for initiating an OFDMA access competition; the initiating an OFDMA access competition within the duration of the OFDMA phase, including: The OFDMA access competition is initiated within the determined size range of the competition window.

In a third aspect, a service access point is provided, where the service access point AP includes:

a boot module for starting an OFDMA phase based on a CSMA/CA mechanism;

a first sending module, configured to send an OFDMA phase initiation indication to the OFDMA STA, and a receiving module, configured to receive a contention access request sent by the at least one OFDMA STA that initiates the OFDMA access competition within the duration of the OFDMA phase;

a configuration module, configured to configure a channel resource for the at least one OFDMA STA according to the contention access request;

And a first notification module, configured to notify the at least one OFDMA STA of the configuration information of the channel resource, and enable the at least one OFDMA STA to perform media access according to the configuration information of the channel resource.

With reference to the third aspect, in a first possible implementation manner of the third aspect, the starting module is configured to initiate a channel competition based on a CSMA/CA mechanism, and start an OFDMA phase;

With reference to the first possible implementation manner of the third aspect, in the second possible implementation manner of the third aspect,

a second sending module, configured to send a channel reservation indication to all STAs in the system, where the channel reservation indication carries a NAV value, so that the STA that receives the channel reservation indication is carried according to the channel reservation indication The N AV value updates the local N AV value.

With reference to the third aspect, in a third possible implementation manner of the third aspect, the first sending mode

With reference to the third aspect, in a fourth possible implementation manner of the third aspect, the foregoing, the AP further includes: a setting module, configured to set a size of a contention window of the OFDMA access competition;

a second notification module, configured to notify the OFDMA STA of a size of a competition window of the OFDMA access competition set by the setting module, so that the OFDMA STA initiates an OFDMA within a size range of the contention window Access to competition.

In a fourth aspect, a site is provided, where the STA includes:

a first receiving module, configured to receive an OFDMA phase start indication sent by the serving access point AP; An initiating module, configured to initiate an OFDMA access competition within an OFDMA phase; the first sending module, configured to send a contention access request to the AP;

a second receiving module, configured to receive configuration information of the channel resource that is notified by the AP after configuring a channel resource according to the contention access request;

The access module is configured to perform media access according to the configuration information of the channel resource.

With reference to the fourth aspect, in a first possible implementation manner of the fourth aspect, the STA further includes:

And a second sending module, configured to send a channel contention request to the AP according to the CSMA/CA mechanism, so that the AP sends the OFDMA phase start indication after starting the OFDMA phase according to the channel contention request.

With reference to the fourth aspect, in a second possible implementation manner of the fourth aspect, the first receiving module is configured to receive an OFDMA phase start indication that is sent by an AP and includes an OFDMA phase duration, where the initiating module is further configured to: The duration of the OFDMA phase is determined according to the OFDMA phase start indication.

With reference to the fourth aspect, in a third possible implementation manner of the fourth aspect, the STA further includes:

a third receiving module, configured to receive a channel reservation indication sent by the AP, where the channel reservation indication carries a NAV value;

The initiating module is further configured to determine an OFDMA phase duration according to the NAV value carried in the channel reservation indication.

With reference to the fourth aspect, in a fourth possible implementation manner of the fourth aspect, the STA further includes:

a determining module, configured to determine, according to the notification of the AP, a size of a competition window for initiating an OFDMA access competition;

The initiating module is configured to initiate an OFDMA access competition within a size range of the determined contention window.

The fifth aspect, further provides a medium access system, where the system includes: a service access point AP and a station STA;

Wherein the AP is an AP as described above;

The STA is as described above for STA. The beneficial effects brought by the technical solutions provided by the embodiments of the present invention are:

The embodiment of the present invention introduces an OFDMA multiple access contention access mechanism, and the AP allocates channel resources for the OFDMA STA according to the OFDMA contention access request of the OFDMA STA, and allocates channel resources to different OFDMA STAs, so that the OFDMA STAs are configured according to the configuration. The information is accessed by the medium to achieve multiple access, which improves the system access efficiency. DRAWINGS

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly described below. It is obvious that the drawings in the following description are only some embodiments of the present invention. For those skilled in the art, other drawings may be obtained based on these drawings without any creative work.

1 is a flowchart of a method for media access according to Embodiment 1 of the present invention;

FIG. 2 is a flowchart of another method for media access according to Embodiment 1 of the present invention; FIG.

3 is a flowchart of a method for media access according to Embodiment 2 of the present invention;

4 is a flowchart of a method for media access according to Embodiment 3 of the present invention;

FIG. 5 is a schematic structural diagram of a first service access point according to Embodiment 4 of the present invention; FIG.

6 is a schematic structural diagram of a second service access point according to Embodiment 4 of the present invention;

7 is a schematic structural diagram of a third service access point according to Embodiment 4 of the present invention;

8 is a schematic structural diagram of a first station according to Embodiment 5 of the present invention;

9 is a schematic structural diagram of a second site according to Embodiment 5 of the present invention;

10 is a schematic structural diagram of a third station according to Embodiment 5 of the present invention;

11 is a schematic structural diagram of a fourth station according to Embodiment 5 of the present invention;

FIG. 12 is a schematic structural diagram of a medium access system according to Embodiment 6 of the present invention. detailed description

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

Embodiment 1

With the increasing use of wireless communication applications and the increasing number of mobile terminals, the requirements for wireless access technologies are becoming higher and higher. In order to improve the access efficiency of the system, this embodiment provides a medium access party. For example, the method provided in this embodiment is used as an example. Referring to FIG. 1 , the process of the method provided in this embodiment is specifically as follows:

101: Start an OFDMA phase based on a CSMA/CA mechanism, and send an OFDMA phase start indication to the OFDMA STA;

102: Receive at least one OFDMA that initiates an OFDMA access competition within an OFDMA phase duration

a contention access request sent by the STA;

103: Configure a channel resource for the at least one OFDMA STA according to the contention access request, and notify the at least one OFDMA STA of the configuration information of the channel resource, so that the at least one OFDMA STA performs media access according to the configuration information of the channel resource.

The method provided in this embodiment is taken as an example from the perspective of the STA. Referring to FIG. 2, the process of the method provided in this embodiment is specifically as follows:

201: Receive an OFDMA phase start indication sent by the AP.

202: Initiating an OFDMA access competition within an OFDMA phase, and sending a contention access request to the AP;

203: Receive configuration information of the channel resource that is notified by the AP after configuring the channel resource according to the contention access request, and perform media access according to the configuration information of the channel resource.

The method provided by the embodiment of the present invention, by introducing an OFDMA multiple access contention access mechanism, the AP allocates channel resources for the OFDMA STA according to the OFDMA contention access request of the OFDMA STA, and allocates channel resources to different OFDMA STAs. The OFDMA STA performs medium access according to the configuration information, implements multiple access, and improves system access efficiency. Embodiment 2

The embodiment of the invention provides a method for media access, which is applicable to a method for implementing an OFDMA multiple access competition access mechanism after the system introduces an OFDMA mechanism and coexists with the CSMA/CA mechanism and the OFDMA mechanism.

In this embodiment, an application scenario consisting of one AP and multiple STAs is used as an example. Generally, in the traditional CSMA/CA mechanism, when an AP and a STA in a BSS compete for a wireless medium (which may be called a contention channel), there is no priority division, which is an equal fair competition. The APs in this embodiment have the OFDMA access function compared with the conventional APs. The STAs in this embodiment are classified into STAs with OFDMA function and no OFDMA. For a functioning STA, an STA having an OFDMA function is referred to as an OFDMA STA. Referring to FIG. 3, the method process provided by this embodiment includes:

301: The AP initiates a channel competition based on the CSMA/CA mechanism, and starts the OFDMA phase. For this step, the manner in which the AP competes for the channel based on the CSMA/CA mechanism includes but is not limited to detecting in the process of participating in channel competition based on the CSMA/CA mechanism. The state of the actual physical link and the NAV value. When the state of the actual physical link is idle and the NAV value is zero, the channel is idle, and the idle channel is contending to start the OFDMA phase.

Specifically, the AP participates in channel competition based on the CSMA/CA mechanism, and detects the actual physical link state and NAV in the carrier sense phase. Among them, NAV is a virtual carrier sensing mechanism defined by IEEE ( Institute of Electrical and Electronics Engineers) 802.11. NAV can be understood as a timer that defines how long the current link will be occupied. For the actual physical link state and NAV, one of which is defined as busy, the line state is busy. If both states are idle, the carrier sense phase considers the line to be idle, so the AP is When the state of the actual physical link is idle and the NAV value is zero, the OFDMA phase is started.

302: The AP sends a channel reservation indication to all STAs in the system, where the channel reservation indication carries a NAV value, so that the STA that receives the channel reservation indication updates the local NAV value according to the NAV value carried in the channel reservation indication, and Transmitting an OFDMA phase initiation indication to the OFDMA STA;

For this step, the manner in which the channel reservation indication is sent to all the STAs in the system includes, but is not limited to, sending a CTS-to-Self (Clear To Send to Self) frame carrying the NAV value to all STAs. The CTS-to-Self frame is used as a channel reservation indication sent by the AP to all STAs, and the channel reservation indication is used to notify all STAs to update the NAV value according to the content carried by the CTS-to-Self indication. Certainly, the AP may also send the channel reservation indication in other manners. This embodiment does not limit the manner in which the AP sends the channel reservation indication to all the STAs in the system, and ensures that the STA that receives the channel reservation indication can correctly set the NAV value. Just fine.

For the Legacy STA (legacy station), the channel reservation indication sent by the AP is received, and the NAV value is updated according to the indicated content, so as to ensure that no data is sent during the next OFDMA competitive access phase, avoiding the OFDMA The STA forms interference. For an OFDMA STA, as an alternative, the OFDMA STA can selectively update its NAV value as an alternative. In the specific implementation, the AP sends a channel reservation indication to the OFDMA STA, which is not specifically limited in this embodiment. The manner in which the AP sends an OFDMA stage start indication to the OFDMA STA is also not specifically limited in this embodiment. In practical applications, the channel reservation and the OFDMA phase start indication may be completed by one frame, for example, directly using the existing bits in the CTS-to-Self to indicate the start of the OFDMA phase, or extending the new bit to indicate the start of the OFDMA phase, therefore, the channel The reservation and OFDMA phase start indications can be combined into one step. Optionally, after receiving the RTS (Request To Send) frame sent by the OFDMA STA, the AP may carry the indication of starting the OFDMA phase in a CTS (Clear To Send) frame to the OFDMA STA.

Further, the method provided by this embodiment starts in the OFDMA phase of the AP transmitting to the OFDMA STA, in order to enable the OFDMA STA to send the OFDMA phase initiation indication to the OFDMA STA, in order to enable the OFDMA STA to enter the OFDMA phase within the duration of the OFDMA phase according to the indication. In addition, the step of transmitting the duration of the OFDMA phase to the OFDMA STA is also included. In a specific implementation, the manner of sending the OFDMA phase duration to the OFDMA STA includes, but is not limited to, sending an OFDMA phase initiation indication including an OFDMA phase duration to the OFDMA STA, so that the OFDMA STA initiates the OFDMA access competition within the OFDMA phase duration.

Optionally, in the method provided in this embodiment, considering the fairness of the STA channel competition, the Backoff mechanism of the contention window may be added. In a specific implementation, the AP may set the size of the competition window of the OFDMA access competition, and notify the OFDMA STA of the size of the set of the competition window of the OFDMA access competition, so that the OFDMA STA is in the size range of the specified competition window. Initiated OFDMA access competition. The embodiment does not limit the manner in which the AP sets the size of the contention window of the OFDMA access competition. During the specific implementation, the AP improves the STA access efficiency, and can comprehensively consider the size of the contention window according to the actual conditions of the network, such as the network busyness and channel utilization.

Further, in order to ensure the fairness of the Legacy STA and the OFDMA STA, a fairness guarantee mechanism may also be introduced on the AP side, for example, by adjusting the time of the AP reserved channel and the time interval for the AP to initiate the competition, etc. STA and OFDMA STA have an opportunity for fair competition.

303: The OFDMA STA receives the channel reservation indication and the OFDMA phase initiation indication sent by the AP. For this step, the embodiment does not limit the manner in which the OFDMA STA receives the channel reservation indication sent by the AP and the OFDMA stage startup indication. If the AP in step 302 sends a channel reservation indication and an OFDMA phase initiation indication to all STAs using a CTS-to-Self frame, the OFDMA STA receives the CTS-to-Self frame.

304: The OFDMA STA determines the duration of the OFDMA phase, and initiates within the duration of the OFDMA phase. OFDMA access competition, sending a competitive access request to ΑΡ;

Specifically, since the channel reservation indication received by the OFDMA STA carries the NAV value, when the OFDMA STA is in data communication, if the channel is occupied, the other STAs are required to be occupied by the durat ion field in various messages. How long is the channel, and the STA that has not acquired the channel resource updates its NAV value by comparing the received durat ion value (it is updated when the received packet's durat ion value is greater than its own NAV t imer), when the NAV value is 0 The current link is considered to be idle. Therefore, the OFDMA STA that receives the channel reservation indication may determine the duration of the OFDMA phase according to the NAV value carried in the channel reservation indication, and when the OFDMA STA has data transmission to the AP, and detects that the physical channel state is idle, in the OFDMA The OFDMA access competition is initiated within the duration of the phase.

It should be noted that, if the AP also sets the size of the contention window of the OFDMA access competition in the above step 302, and notifies the OFDMA STA of the size of the set of the competition window of the OFDMA access competition, the step is The OFDMA STA needs to determine the size of the contention window for initiating the OFDMA access competition according to the notification of the AP, and initiate the OFDMA access competition within the determined size range of the competition window.

305: The AP receives at least one of the OFDMA access competitions initiated within the duration of the OFDMA phase.

a contention access request sent by the OFDMA STA;

For this step, the OFDMA STAs that receive the OFDMA phase initiation indication sent by the AP have the opportunity of the OFDMA access competition, and at least one OFDMA STA starts the OFDMA phase according to the foregoing indication, and after determining the duration of the OFDMA phase, it will be within the duration of the OFDMA phase. The OFDMA access competition is initiated, and a contention access request is sent to the AP. Therefore, the AP may receive a contention access request sent by at least one OFDMA STA that initiates the OFDMA access competition within the duration of the OFDMA phase.

306: The AP configures a channel resource for the at least one OFDMA STA according to the contention access request, and notifies the at least one OFDMA STA of the channel resource configuration information.

Specifically, this embodiment does not limit the manner in which the AP allocates channel resources for at least one OFDMA STA according to the contention access request. In a specific implementation, the AP may divide the channel into orthogonal sets of subcarriers that do not overlap each other, and allocate different subcarrier sets to different OFDMA STAs to implement configuration of channel resources of multiple OFDMA STAs.

The manner in which the AP notifies the configuration information of the channel resources to the at least one OFDMA STA is not specifically limited. The method includes, but is not limited to, the AP may notify the configuration information of the channel resource to the at least one OFDMA STA by sending a data frame. 307: The OFDMA STA receives the configuration information of the channel resource that is notified by the AP after configuring the channel resource according to the contention access request, and performs media access according to the configuration information of the channel resource.

For this step, after the OFDMA STA receives the configuration information of the channel resource that is notified by the AP after configuring the channel resource according to the contention access request, if the channel resource is configured, the AP divides the channel into orthogonal series that do not overlap each other. A subset of subcarriers is allocated to different OFDMA STAs, and each OFDMA STA that receives configuration information of channel resources notified by the AP can perform signal modulation according to the subcarrier set allocated by the AP, thereby implementing Multiple access.

The method provided by the embodiment of the present invention, by introducing an OFDMA multiple access contention access mechanism, the AP indicates that the OFDMA STA starts the OFDMA phase, and the OFDMA STA initiates the OFDMA access competition according to the indication of the AP, and sends a contention access request to the AP. The AP allocates channel resources for the OFDMA STA according to the contention access request, divides the channel into orthogonal sets of subcarriers that do not overlap each other, and allocates different subcarrier sets to different OFDMA STAs, so that the OFDMA STAs are based on channel resources. The configuration information is used for medium access, achieving multiple access, and improving system access efficiency. Embodiment 3

Embodiments of the present invention provide a method for media access. This embodiment is applicable to the method of implementing the OFDMA multiple access competition access mechanism after the system introduces the OFDMA mechanism and coexists with the CSMA/CA mechanism and the OFDMA mechanism. Compared with the conventional AP, the AP related to the embodiment has the OFDMA access function. In this embodiment, the specific application scenario is the same as that in the second embodiment. The difference is that the second embodiment directly reserves the channel after the AP competes. In this embodiment, after the OFDMA STA successfully acquires the channel, the AP indicates to enter the OFDMA. The stage of competition. Referring to FIG. 4, the method process provided by this embodiment includes:

401: The OFDMA STA sends a channel contention request to the AP according to the CSMA/CA mechanism. Specifically, when the OFDMA STA needs the contention channel, the channel contention request is sent to the AP, so that the AP starts the OFDMA phase according to the channel contention request.

The embodiment does not limit the manner in which the OFDMA STA sends a channel contention request to the AP, including but not limited to carrying the channel contention request in an RTS (Request To Send) frame, and the AP receives the RTS. A CTS (Clear To Send) frame is returned to the OFDMA STA after the frame, and the OFDMA phase is started.

Further, the channel contention request may further include an OFDMA STA successfully acquiring the letter. The length of time information.

402: The AP receives the channel contention request sent by the OFDMA STA based on the CSMA/CA mechanism, and starts the OFDMA phase according to the channel contention request.

For this step, the embodiment does not limit the manner in which the AP receives the channel contention request sent by the OFDMA STA based on the CSMA/CA mechanism. In any manner, the AP may start the OFDMA according to the channel contention request. stage. In the manner that the AP initiates the OFDMA phase, the AP can also initiate the OFDMA phase by:

Specifically, the OFDMA STA initiates channel competition, and may use the RTS/CTS mechanism in the channel competition process, that is, if the AP knows that the STA has the OFDMA function, it may utilize some existing bits or newly extended bits in the CTS. Directly notifying the OFDMA STA The next time period is used as the OFDMA phase, so that the STA does not need to separately send a channel contention request to the AP, and the AP will directly instruct all OFDMA STAs to enter the OFDMA phase.

403: The AP sends an OFDMA phase start indication to the OFDMA STA.

For this step, this embodiment does not limit the manner in which the AP sends the OFDMA phase start indication to the OFDMA STA. In a specific implementation manner, the specific implementation manner of the AP transmitting the OFDMA phase initiation indication to the OFDMA STA may be the same as the manner in which the AP sends the OFDMA phase initiation indication to the OFDMA STA in the step 302 in the foregoing Embodiment 2. For details, refer to step 302 in the foregoing Embodiment 2. The content of this, will not repeat them here.

It should be noted that, because the channel reservation success indication sent by the OFDMA STA after acquiring the channel may further include the duration information of the successfully acquired channel of the OFDMA STA, after the AP receives the channel reservation success indication, in order to make the system The OFDMA STA can initiate an access competition according to the duration of the OFDMA phase, and the OFDMA phase initiation indication sent by the AP to the OFDMA STA can further include the duration of the OFDMA phase. Alternatively, in the case that the AP does not notify the OFDMA STA of the duration of the OFDMA phase, the OFDMA STA directly utilizes the NAV value set by the local end in the RTS/CTS process of the previously successfully acquired channel as the duration of the OFDMA phase. If the original NAV value of the OFDMA STA is used as the duration of the OFDMA phase, the AP does not need to perform channel reservation, but directly instructs all OFDMA STAs to enter the OFDAM phase.

404: The OFDMA STA receives an OFDMA phase start indication sent by the AP. For the step, the specific implementation manner of the OFDMA STA to receive the OFDMA phase initiation indication sent by the AP is the same as that of the OFDMA phase initiation indication sent by the OFDMA STA in the step 303 in the second embodiment. For details, refer to the steps in the foregoing Embodiment 2. The content of 303 will not be described here.

405: OFDMA STA determines the duration of the OFDMA phase, initiated within the duration of the OFDMA phase

The OFDMA accesses the competition and sends a contention access request to the AP;

For this step, the OFDMA STA determines the duration of the OFDMA phase, initiates the OFDMA access competition within the duration of the OFDMA phase, and transmits the contention request to the AP. The OFDMA STA determines the OFDMA phase in step 304 in the second embodiment. The duration of the OFDMA access is initiated in the period of the OFDMA, and the content of the access request is sent to the AP in the same manner. For details, refer to the content of step 304 in the foregoing embodiment 2, and details are not described herein again.

406: The AP receives a contention access request sent by at least one OFDMA STA that initiates an OFDMA access competition within an OFDMA phase duration;

For this step, the specific implementation manner of the AP receiving the contention access request sent by the at least one OFDMA STA that initiates the OFDMA access competition in the duration of the OFDMA phase is initiated in step 305 of the foregoing Embodiment 2, and the AP receiving is initiated within the duration of the OFDMA phase. The manner in which the at least one OFDMA STA of the OFDMA access is sent is the same. For details, refer to the content of the step 305 in the foregoing Embodiment 2, and details are not described herein again.

407: The AP allocates a channel resource to the at least one OFDMA STA according to the contention access request, and notifies the at least one OFDMA STA of the channel resource configuration information.

For the step, the AP configures the channel resource for the at least one OFDMA STA according to the contention access request, and the specific implementation manner of notifying the configuration information of the channel resource to the at least one OFDMA STA, and the AP according to the step 306 in the foregoing Embodiment 2 The method for configuring the channel resource for the at least one OFDMA STA and the configuration information of the channel resource to the at least one OFDMA STA is the same. For details, refer to the content of the step 306 in the foregoing Embodiment 2, and details are not described herein again.

408: The OFDMA STA receives the configuration information of the channel resource that is notified by the AP after configuring the channel resource according to the contention access request, and performs media access according to the configuration information of the channel resource.

For the step, the OFDMA STA receives the configuration information of the channel resource that is notified by the AP after the channel resource is configured according to the contention access request, and performs the medium access according to the configuration information of the channel resource, and the step 307 in the second embodiment. The OFDMA STA receives the AP according to the contention access request The configuration information of the channel resources that are notified after the channel resource is configured, and the manner of the media access is the same according to the configuration information of the channel resources. For details, refer to the content of the step 307 in the foregoing Embodiment 2, and details are not described herein again.

The method provided by the embodiment of the present invention, by introducing an OFDMA multiple access contention access mechanism, the OFDMA STA sends a channel contention request to the AP, then the AP starts the OFDMA phase, and instructs the OFDMA STA to start the OFDMA phase, and the OFDMA STA initiates according to the indication of the AP. The OFDMA accesses the competition and sends a contention access request to the AP. The AP allocates channel resources for the OFDMA STA according to the contention access request, and divides the channel into orthogonal sets of subcarriers that do not overlap each other, which will be different. The subcarrier set is allocated to different OFDMA STAs, and the OFDMA STA performs medium access according to the configuration information of the channel resources, thereby implementing multiple access, and improving system access efficiency. Embodiment 4

The embodiment provides a service access point, where the service access point AP is configured to perform the functions performed by the AP in any of the foregoing Embodiments 1 to 3. Referring to FIG. 5, the AP includes:

a startup module 501, configured to start an OFDMA phase based on a CSMA/CA mechanism;

a first sending module 502, configured to send an OFDMA phase initiation indication to the OFDMA STA, and a receiving module 503, configured to receive a contention access request sent by the at least one OFDMA STA that initiates the OFDMA access competition within the duration of the OFDMA phase;

The configuration module 504 is configured to configure channel resources for the at least one OFDMA STA according to the contention access request;

The first notification module 505 is configured to notify configuration information of the channel resource to the at least one OFDMA STA, so that the at least one OFDMA STA performs media access according to the configuration information of the channel resource.

Specifically, the starting module 501 is configured to initiate a channel competition based on a CSMA/CA mechanism, and start an OFDMA phase;

Referring to Figure 6, the AP also includes:

The second sending module 506 is configured to send a channel reservation indication to all STAs in the system, where the channel reservation indication carries a NAV value, so that the STA that receives the channel reservation indication updates the local according to the NAV value carried in the channel reservation indication. NAV value. Specifically, the first sending mode 502 is configured to send an OFDMA phase initiation indication including an OFDMA phase duration to the OFDMA STA, so that the OFDMA STA initiates the OFDMA access competition within the OFDMA phase duration.

Referring to Figure 7, the AP also includes:

a setting module 507, configured to set a size of a competition window of the OFDMA access competition;

The second notification module 508 is configured to notify the OFDMA STA of the size of the contention window of the OFDMA access competition set by the setting module, so that the OFDMA STA initiates the OFDMA access competition within the size range of the contention window.

The service access point provided by the embodiment provides a channel resource for the OFDMA STA by introducing an OFDMA function, and divides the channel into orthogonal non-overlapping portions and allocates them to different OFDMA STAs, so that the OFDMA STAs are based on the channel. The resource configuration information is used for medium access, which realizes multiple access and improves system access efficiency. Embodiment 5

The present embodiment provides a site, where the STA is used to perform the functions performed by the STA in any of the foregoing Embodiments 1 to 4. Referring to FIG. 8, the STA includes:

The first receiving module 801 is configured to receive an OFDMA phase initiation indication sent by the serving access point AP, and the initiating module 802 is configured to initiate an OFDMA access competition within an OFDMA phase duration. The first sending module 803 is configured to send to the AP. Competing for access requests;

The second receiving module 804 is configured to receive configuration information of the channel resource that is notified by the AP after configuring the channel resource according to the contention access request.

The access module 805 is configured to perform media access according to configuration information of the channel resource.

Referring to Figure 9, the STA also includes:

The second sending module 806 is configured to send a channel contention request to the AP according to the CSMA/CA mechanism, so that the AP sends an OFDMA phase start indication after starting the OFDMA phase according to the channel contention request.

Specifically, the first receiving module 801 is configured to receive an OFDMA phase start indication that is sent by the AP and includes an OFDMA phase duration.

The initiating module 802 is further configured to determine an OFDMA phase duration according to the OFDMA phase startup indication. Referring to FIG. 10, the STA further includes:

The third receiving module 807 is configured to receive a channel reservation indication sent by the AP, and carry the channel reservation indication With a NAV value;

The initiating module 802 is further configured to determine an OFDMA phase duration according to the NAV value carried in the channel reservation indication.

Referring to FIG. 11, the STA further includes:

a determining module 808, configured to determine, according to the notification of the AP, a size of a competition window for initiating an OFDMA access competition;

The initiating module 802 is configured to initiate an OFDMA access competition within a determined size range of the contention window.

The site provided in this embodiment implements the OFDMA function, and the OFDMA STA performs media access according to the configuration information of the channel resources sent by the AP, thereby implementing multiple access, and improving system access efficiency. Embodiment 6

The present embodiment provides a medium access system, which is used to perform the method provided by any one of the foregoing embodiments 1 to 4. Referring to FIG. 12, the system includes:

The service access point AP 1201 and the AP are as described in the foregoing embodiment 4. For details, refer to the content of the foregoing embodiment 4, and details are not described herein again.

For the details of the STAs in the foregoing Embodiment 5, the details of the STAs are as follows.

In the system provided by the embodiment, the AP and the OFDMA STA both have the OFDMA function, and the AP configures the channel resource according to the contention access request of the OFDMA STA, so that the OFDMA STA performs medium access according to the channel resource configuration information. OFDMA multiple access improves system access efficiency. It should be noted that, when the service access point and the site provided by the foregoing embodiment implement media access, only the division of each functional module is described. In actual applications, the foregoing functions may be allocated differently according to requirements. The function module is completed, and the internal structure of the service access point and the site is divided into different functional modules to complete all or part of the functions described above. In addition, the service access point, the site, the medium access system, and the media access method are provided in the same embodiment. The specific implementation process is described in the method embodiment, and details are not described herein.

The serial numbers of the embodiments of the present invention are merely for the description, and do not represent the advantages and disadvantages of the embodiments. A person skilled in the art may understand that all or part of the steps of implementing the above embodiments may be completed by hardware, or may be instructed by a program to execute related hardware. The program of the above embodiment may be stored in a computer readable storage medium. The above-mentioned storage medium may be a read only memory, a magnetic disk or an optical disk or the like.

The above is only the preferred embodiment of the present invention, and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., which are within the spirit and scope of the present invention, should be included in the protection of the present invention. Within the scope.

Claims

claims

1. A medium access method, characterized in that the method includes:

Start the Orthogonal Frequency Division Multiple Access OFDMA phase based on the carrier sensing multi-point access/collision avoidance CSMA/CA mechanism, and send the OFDMA phase start indication to the OFDMA station STA;

Receive at least one OFDMA that initiated OFDMA access contention within the OFDMA phase duration.

Contention access request sent by STA;

Configure channel resources for the at least one OFDMA STA according to the competition access request, and notify the at least one OFDMA STA of the configuration information of the channel resources, so that the at least one OFDMA STA can configure the channel resources according to the configuration information of the channel resources. Configuration information for media access.

2. The method according to claim 1, characterized in that the carrier sensing multi-point access/collision avoidance CSMA/CA mechanism starts the Orthogonal Frequency Division Multiple Access OFDMA phase, including:

Initiate channel competition based on the CSMA/CA mechanism and start the OFDMA phase;

Or, receive the channel competition request sent by the OFDMA STA based on the CSMA/CA mechanism, and start the OFDMA phase according to the channel competition request.

3. The method according to claim 2, characterized in that, after the carrier sensing-based multi-point access/collision avoidance CSMA/CA mechanism starts the Orthogonal Frequency Division Multiple Access OFDMA phase, it also includes:

Send a channel reservation indication to all STAs in the system. The channel reservation indication carries a NAV value, so that the STA that receives the channel reservation indication updates the local NAV according to the NAV value carried in the channel reservation indication. value.

4. The method according to claim 1, characterized in that, sending the OFDMA phase start instruction to the OFDMA STA includes:

Send an OFDMA phase start instruction containing the OFDMA phase duration to the OFDMA STA, so that

5. The method according to claim 1, characterized in that, before receiving a contention access request sent by at least one OFDMA STA that initiates OFDMA access contention within the OFDMA phase duration, the method further includes: Set the size of the competition window for OFDMA access competition, and notify the OFDMA STA of the set size of the competition window for OFDMA access competition, so that the OFDMA STA is within the size range of the competition window OFDMA access competition is initiated.

6. A medium access method, characterized in that the method includes:

Receive the OFDMA phase start indication sent by the service access point AP;

Initiate OFDMA access competition within the OFDMA phase duration, and send a competition access request to the AP;

Receive the configuration information of the channel resource notified by the AP after configuring the channel resource according to the competition access request, and perform medium access according to the configuration information of the channel resource.

7. The method according to claim 6, characterized in that before receiving the OFDMA phase start indication sent by the AP, it further includes:

The CSMA/CA mechanism based on carrier sensing multi-point access/collision avoidance sends a channel competition request to the AP, so that the AP starts the OFDMA phase according to the channel competition request and then sends the OFDMA phase start instruction.

8. The method according to claim 6, wherein the OFDMA phase start indication sent by the receiving AP includes:

Receive an OFDMA phase start indication sent by the AP including the OFDMA phase duration; before initiating OFDMA access competition within the OFDMA phase duration, the method further includes: determining the OFDMA phase duration according to the OFDMA phase start indication.

9. The method according to claim 6, characterized in that, before initiating OFDMA access competition within the duration of the OFDMA phase, the method further includes:

Receive the channel reservation indication sent by the AP, the channel reservation indication carries a NAV value; determine the OFDMA phase duration according to the NAV value carried in the channel reservation indication.

10. The method according to claim 6, characterized in that, before initiating OFDMA access competition within the duration of the OFDMA phase, it further includes:

Determine the size of the competition window for initiating OFDMA access competition according to the notification from the AP; The initiating OFDMA access competition within the OFDMA phase duration includes: initiating OFDMA access competition within a determined competition window size range.

11. A service access point, characterized in that the service access point AP includes:

Startup module, used to start the orthogonal frequency division multiple access OFDMA phase based on the carrier sensing multi-point access/collision avoidance CSMA/CA mechanism;

The first sending module is used to send an OFDMA phase start instruction to the OFDMA STA; the receiving module is used to receive a contention access request sent by at least one OFDMA STA that initiates OFDMA access contention within the duration of the OFDMA phase;

A configuration module configured to configure channel resources for the at least one OFDMA STA according to the contention access request;

The first notification module is configured to notify the at least one OFDMA STA of the configuration information of the channel resource, so that the at least one OFDMA STA performs medium access according to the configuration information of the channel resource.

12. The AP according to claim 11, characterized in that the startup module is used to initiate channel competition based on the CSMA/CA mechanism and start the OFDMA phase;

13. The AP according to claim 12, characterized in that, the AP further includes: a second sending module, configured to send a channel reservation indication to all STAs in the system, and the channel reservation indication carries NAV value, so that the STA that receives the channel reservation indication updates the local NAV value according to the NAV value carried in the channel reservation indication.

14. The AP according to claim 11, characterized in that the first sending module is configured to send an OFDMA phase start instruction including the OFDMA phase duration to the OFDMA STA, so that the

15. The AP according to claim 11, characterized in that, the AP further includes:

Setting module, used to set the size of the competition window for OFDMA access competition; The second notification module is configured to notify the OFDMA STA of the size of the competition window for OFDMA access competition set by the setting module, so that the OFDMA STA initiates OFDMA within the size range of the competition window. Enter the competition.

16. A site, characterized in that the site STA includes:

The first receiving module is used to receive the OFDMA phase start instruction sent by the service access point AP; the initiating module is used to initiate OFDMA access competition within the OFDMA phase duration;

The first sending module is used to send a competition access request to the AP;

The second receiving module is configured to receive the configuration information of the channel resources notified by the AP after configuring the channel resources according to the competition access request;

An access module, configured to perform medium access according to the configuration information of the channel resources.

17. The STA according to claim 16, characterized in that, the STA further includes: a second sending module, configured to send a channel contention message to the AP based on the carrier sensing multi-point access/collision avoidance CSMA/CA mechanism. request, causing the AP to send the OFDMA phase start indication after starting the OFDMA phase according to the channel competition request.

18. The STA according to claim 16, wherein the first receiving module is configured to receive an OFDMA phase start indication sent by the AP including the OFDMA phase duration;

The initiating module is also configured to determine the duration of the OFDMA phase according to the OFDMA phase start indication.

19. The STA according to claim 16, characterized in that, the STA further includes: a third receiving module, configured to receive a channel reservation indication sent by the AP, and the channel reservation indication carries a NAV value ;

The initiating module is also configured to determine the OFDMA phase duration according to the NAV value carried in the channel reservation indication.

20. The STA according to claim 16, characterized in that, the STA further includes: a determination module, configured to determine the size of the competition window for initiating OFDMA access competition according to the notification from the AP; The initiating module is used to initiate OFDMA access competition within the determined size range of the competition window.

21. A medium access system, characterized in that the system includes: a service access point AP and a site STA;

Wherein, the AP is the AP described in any one of claims 11 to 15;

The STA is the STA described in any one of claims 16 to 20.