WO2015000304A1

WO2015000304A1 - Uplink sending power calibration method, and related device and system

Info

Publication number: WO2015000304A1
Application number: PCT/CN2014/072408
Authority: WO
Inventors: 伍天宇; 李云波; 罗毅
Original assignee: 华为技术有限公司
Priority date: 2013-07-02
Filing date: 2014-02-22
Publication date: 2015-01-08
Also published as: CN104284408B; CN104284408A

Abstract

Disclosed are an uplink sending power calibration method, and a related device and system. The uplink sending power calibration method comprises: receiving a power calibration frame sent by an access point, the power calibration frame comprising a target receiving power and a current sending power; and adjusting an uplink sending power according to the target receiving power and the current sending power, so that differences between receiving powers of the access point on different subcarriers or subchannels are within a preset difference range. A problem that all uplink data cannot be received normally when differences between uplink sending powers of different sites received in an uplink OFDMA communication process are relatively large can be solved, and a problem of great interference between users when differences between uplink sending powers of different sites received in a multi-user multi-input multi-output (MU-MIMO) system are relatively large can be solved.

Description

Uplink transmission power calibration method and related equipment and system thereof

The present application relates to the field of network communications, and more particularly to an uplink transmit power calibration method and related devices and systems. Background technique

Orthogonal Frequency-Division Multiple Access (OFDMA) is an evolution of Orthogonal Frequency Division Multiplexing (OFDM). The OFDMA access system divides the transmission bandwidth into orthogonal non-overlapping channels. A series of subcarrier sets, different sets of subcarriers are allocated to different users to achieve multiple access, that is, total resources, such as time and bandwidth, are segmented in frequency to achieve multi-user diversity gain and improve system throughput. At the same time, the application of OFDMA technology may also reduce the collision probability of channel competition and reduce the delay of data packets. Using OFDMA technology on the upstream channel, the access point can receive packets from multiple sites simultaneously. In this case, in order to correctly receive uplink data of multiple stations in the OFDMA symbol, the access point needs to set an appropriate automatic gain control value to make all stations in the OFDMA symbol operate in the linear range of the amplifier, which requires the OFDMA symbol. The power of all the stations in the access point to the access point is close.

In order to avoid the problem of entering a new hidden node, in the existing uplink OFDMA communication, uplink power control is not performed, that is, the access point and the node both use fixed transmission power, and this mechanism is used in the uplink access process. The power of the channel access information sent by different users near the access point is different, which greatly reduces the success rate of access, for example:

a The near-end user and the remote user are connected in the same sub-band. The power of the near-end user received by the access point is much larger than that of the remote user. Due to the absorption effect, the near-end user successfully accesses and the remote user access fails.

b The near-end user and the remote user are connected in the same sub-band, and the power of the near-end user signal received by the access point is not much different from the power of the far-end user signal, and the near-end user conflicts with the remote user. Access failed

C The near-end user and the remote user are connected in different sub-bands. The access point sets the automatic gain control according to the received total signal power. The remote user signal is not amplified enough, and the access may fail.

In the uplink OFDMA communication, if the received powers on different subcarrier channels are different, the signal reception with less power may be failed, and in this mechanism, the station access channel is farther away from the access point. Difficult, but for sites with close distances, the transmission power is more difficult than the actual required transmission power, the power saving performance is poor, and it is easy to cause additional interference to other devices, so the signal power transmitted by different stations is received during the uplink OFDMA communication. When the difference is large, it is difficult for the access point to receive the user data normally. Summary of the invention

The embodiment of the present invention provides an uplink transmission power calibration method, device, and system. It is desirable to solve the problem that it is difficult to receive all uplink data normally when the uplink transmission power of different sites is received in the uplink OFDMA communication process is large, and the problem is solved. When the uplink transmit power of different sites received in the uplink multi-user input/output (MU-MIMO) system is large, the interference between users is large.

The first aspect provides an uplink transmit power calibration method, including the following steps: receiving a power calibration frame sent by an access point, where the power calibration frame includes a target received power and a current transmit power; and adjusting an uplink transmit power according to the target received power and the current transmit power. So that the received power of the access point on different subcarriers or subchannels is within a preset difference range.

In a first possible implementation manner of the first aspect, adjusting the uplink transmit power according to the target received power and the current transmit power includes: measuring a received power of the receive power calibration frame, and calculating, according to the received power and the current transmit power, the access point The path loss is calculated according to the target received power and the path loss; the uplink transmit power is calculated according to the target transmit power and the transmit bandwidth, where the transmit bandwidth includes the local transmit bandwidth and the transmit bandwidth of the access point.

With reference to the first aspect, the first possible implementation manner of the first aspect, in a second possible implementation, the step of receiving the power calibration frame sent by the access point further includes: accessing The point sends the current grouping parameter, so that the access point generates the grouping information according to the grouping parameter to set the site of the access channel, and sets the target receiving power for each group, the grouping parameter packet Including the distance or path loss to the access point; receiving the group information sent by the access point so that the station groups according to the group information, the group information includes the identifier of the station included in each group, the group number of each group, and the corresponding target Receiving power; after the station accepts the power calibration frame sent by the access point, selecting the currently accessed packet according to the target received power carried by the power calibration frame, so that the currently accessed packet is based on the target received power carried by the power calibration frame and The current transmit power adjusts the uplink transmit power.

With reference to the second possible implementation manner of the first aspect, in a third possible implementation manner, when a packet parameter changes, a corresponding packet number is found according to the changed packet parameter; and a packet update is sent to the access point. The request frame, the packet update request frame includes a new packet number; the packet adjustment frame sent by the access point is received, and the packet adjustment frame includes a new packet number.

With reference to the second possible implementation manner or the third possible implementation manner of the first aspect, in a fifth possible implementation manner, after the step of receiving the power calibration frame sent by the access point, the method further includes: using a standard power direction The access point sends a compatible request sending frame, so that the access point sends a frame according to the request to return a compatible channel, and the frame can be sent. The request sending frame includes a network allocation vector; and the channel returned by the receiving access point can send a frame to ensure that the frame is transmitted. The uplink data transmission of a certain packet within a time indicated by the network allocation vector, and the channel idle transmission frame includes a network allocation vector.

The second aspect provides an uplink transmit power calibration method, including the following steps: sending a power calibration frame to a station in a wireless local area network, so that the station adjusts the uplink transmit power according to the target received power and the current transmit power carried by the power calibration frame, thereby The difference between the actual received power of the access point receiving the uplink data sent by the access point is within a preset range; and the uplink data sent by the receiving station according to the adjusted uplink transmit power.

In a first possible implementation manner of the second aspect, the step of transmitting the power calibration frame to the station in the wireless local area network further includes: setting a plurality of target received powers, and dividing the target received power into multiple levels; The station transmit power calibration frame includes: transmitting a power calibration frame containing different target received powers to the station, so that after the power calibration frame containing a certain target received power is transmitted, the next power calibration frame containing another target received power Before the transmission, the station whose uplink transmission power is smaller than the maximum allowable transmission power of the station can compete for access to the channel. With reference to the first possible implementation manner of the second aspect, in a second possible implementation manner, before the step of sending, by the access point, the power calibration frame to the station in the WLAN, the method further includes: receiving a packet parameter sent by the station, grouping The parameters include the distance from the site to the access point or the path loss; determine the grouping of the station according to the distance or path loss, set only one group of access channels at a time, and set the target receiving power for each group; the power calibration frame also includes the grouping No., where the packet number corresponds to the target received power.

With the second possible implementation of the second aspect, in a third possible implementation, after the step of receiving the uplink data sent by the station according to the adjusted uplink transmit power, the method further includes: when a new site is associated with the local device At the in point, the new station is grouped according to the grouping parameters of the new station; the power calibration frame is sent to the new station.

With the third possible implementation of the second aspect, in a fourth possible implementation, after the step of receiving, by the receiving station, the uplink data sent according to the adjusted uplink transmit power, the method further includes: when detecting that the wireless local area network has When the grouping parameters of the site change, the grouping of the station is changed, and the grouping adjustment frame is sent to the station, and the packet adjustment frame includes the new grouping number.

With the fourth possible implementation of the second aspect, in a fifth possible implementation, after the step of sending a power calibration frame to a station in the WLAN, the method further includes: receiving a request sending frame sent by the station, requesting to send the frame Including the network allocation vector; according to the request to send the frame return channel idle, the frame can be sent to ensure the uplink data transmission of a certain packet in the time indicated by the network allocation vector, and the channel idle transmission frame includes the network allocation vector.

The third aspect provides a station, including: a power calibration frame receiving module, configured to receive a power calibration frame sent by an access point, where the power calibration frame includes a target received power and a current transmit power; and an uplink transmit power adjustment module, configured to use the target The received power and the current transmit power adjust the uplink transmit power so that the received power of the access point on different subcarriers or subchannels is within a preset difference range.

In a first possible implementation manner of the third aspect, the power calibration frame receiving module includes: a measuring unit, configured to measure a received power of the received power calibration frame, and calculate a path to the access point according to the received power and the current transmit power. a target transmit power calculation unit, configured to calculate a target transmit power according to a target received power and a path loss; an uplink transmit power calculation unit, The uplink transmit power is calculated according to the target transmit power and the transmit bandwidth, where the transmit bandwidth includes a local transmit bandwidth and a transmit bandwidth of the access point.

With reference to the third aspect, or the first possible implementation manner of the third aspect, in a second possible implementation manner, the station further includes: a packet parameter sending module, configured to send the current packet parameter to the access point, to enable The ingress point sets the grouping information according to the grouping parameter to set the site of the access channel, and sets the target receiving power for each packet, the packet parameter includes the distance to the access point or the path loss; the packet information receiving module is configured to receive the access point to send The grouping information thus causes the station to group according to the grouping information, the grouping information including the identifier of the station included in each group, the group number of each group and the corresponding target receiving power; so that the station accepts the power calibration frame sent by the access point And selecting, according to the target received power carried in the power calibration frame, the currently accessed packet, so that the currently accessed packet adjusts the uplink transmit power according to the target received power and the current transmit power carried by the power calibration frame.

With reference to the second possible implementation manner of the third aspect, in a third possible implementation manner, the station further includes: a packet searching module, when the grouping parameter changes, searching for the corresponding group number according to the changed grouping parameter And an update frame sending module, configured to send a packet update request frame to the access point, where the packet update request frame includes a new packet number, and a packet update acknowledgement frame receiving module, configured to receive the packet adjustment frame sent by the access point, and the packet adjustment frame Includes the new group number.

With reference to the second possible implementation manner or the third possible implementation manner of the third aspect, in a fourth possible implementation manner, the station further includes: a request sending frame sending module, configured to send to the access point by using standard power The compatible request sends a frame, so that the access point sends a frame according to the request to return a compatible channel, and the frame can be sent, and the request sending frame includes a network allocation vector; the channel idle can send a frame receiving module, and is used to receive the channel that the access point returns. A frame may be transmitted to ensure uplink data transmission of a certain packet within a time indicated by the network allocation vector, and the channel idle transmission frame may include a network allocation vector.

The fourth aspect provides an access point, including: a power calibration frame sending module, configured to send a power calibration frame to a station in a wireless local area network, so that the station adjusts the uplink sending according to the target receiving power and the current sending power carried by the power calibration frame. The power, so that the difference between the actual received power of the access point receiving the uplink data sent by the access point is within a preset range; the uplink data receiving mode Block, configured to receive uplink data sent by the station according to the adjusted uplink transmit power.

In a first possible implementation manner of the fourth aspect, the access point further includes: a setting module, configured to set multiple target received powers, and divide the target received power into multiple levels; and a power calibration frame sending module, configured to: Sending a power calibration frame containing different target received powers to the station, so that after the power calibration frame containing a certain target received power is transmitted, the uplink transmit power is less than the maximum of the station before the next power calibration frame containing another target received power is transmitted. Sites that allow transmission power can compete for access to the channel.

In a second possible implementation manner of the fourth aspect, the access point further includes: a packet parameter receiving module, configured to receive a packet parameter sent by the station, and output the packet parameter to the grouping module, where the grouping parameter includes the site to the access point Distance or path loss; a grouping module for grouping stations according to distance or path loss, setting only one set of station access channels at a time, and setting target receiving power for each group; the power calibration frame also includes a group number, The packet number corresponds to the target received power.

In a third possible implementation manner of the fourth aspect, the access point further includes: a grouping module, configured to group the new station according to a grouping parameter of the new station when a new station is associated with the access point; A calibration frame sending module is configured to send a power calibration frame to the new station.

In a fourth possible implementation manner of the fourth aspect, the access point further includes: a packet replacement module, configured to: when detecting that a packet parameter of a site in the wireless local area network changes needs to be replaced, the group of the site is replaced, And sending a packet adjustment frame to the station, and the packet adjustment frame includes a new packet number.

In a fifth possible implementation manner of the fourth aspect, the access point further includes: a request sending frame receiving module, configured to receive a request sending frame sent by the station, where the request sending frame includes a network allocation vector; and the channel idle may send the frame sending The module is configured to send a frame according to the request, and return a channel idle to send a frame to ensure uplink data transmission of a certain packet within a time indicated by the network allocation vector, and the channel idle transmission frame includes a network allocation vector.

A fifth aspect provides a wireless local area network communication system, including the third aspect, the station according to any one of the first to fourth possible implementation manners of the third aspect, and the fourth aspect, the first aspect of the fourth aspect The access point of any of the fifth possible implementations.

According to the above analysis, in the present invention, the station calibrates the power transmitted by the receiving access point. And adjusting the uplink transmit power according to the target received power and the current transmit power carried in the power calibration frame, so that the received power of the access point on different subcarriers or subchannels is within a preset difference range; The difference in uplink transmit power of each station in the WLAN received by the access point is small, so that the uplink data can be better received. DRAWINGS

1 is a flowchart of an uplink transmit power calibration method according to an embodiment of the present invention; FIG. 2 is another flow chart of an uplink transmit power calibration method according to an embodiment of the present invention;

3 is a schematic diagram of a hidden node according to an embodiment of the present invention;

4 is another flow chart of an uplink transmit power calibration method according to an embodiment of the present invention;

FIG. 5 is another flow chart of an uplink transmit power calibration method according to an embodiment of the present invention; FIG.

6 is a flowchart of an uplink transmit power calibration method provided by an application example of the present invention; FIG. 7 is a schematic diagram of a logical structure of a site according to an embodiment of the present invention; FIG. 8 is a schematic diagram of a site provided by an embodiment of the present invention; FIG. 9 is a schematic diagram of a logical structure of an access point according to an embodiment of the present invention; FIG. 10 is a schematic diagram of another logical structure of an access point according to an embodiment of the present invention; FIG. 12 is a schematic diagram of another logical structure of an access point according to an embodiment of the present invention; FIG. 13 is a schematic diagram of a logical structure of an access point according to an embodiment of the present invention; Schematic diagram of the logical structure of the system. detailed description

The embodiment of the present invention provides an uplink transmit power calibration method, a corresponding device, and a wireless local area communication network system. The station STA can adjust the uplink transmit power of the local station by using the power calibration frame sent by the access point AP, so that the access point is The received power on different subcarriers or subchannels is within a preset difference range; thus, the uplink transmit power difference of each station in the WLAN received by the access point is small, so that the uplink data can be better received. Detailed below Description.

Referring to FIG. 1, FIG. 1 is a flowchart of an uplink transmit power calibration method according to an embodiment of the present invention. It should be noted that, in this embodiment, the site is mainly used for description. As shown in FIG. 1, the method may include the following steps.

101. Receive a power calibration frame sent by the access point.

First, the access point sends a power calibration frame to each station in the WLAN, and the access point may send a power calibration frame to each station in the WLAN, or may broadcast a power calibration frame in the WLAN, which is not limited by the present invention. The power calibration frame includes a target received power and a current transmit power.

The station receives a power calibration frame sent by the access point.

102. Adjust an uplink transmit power according to the target received power and the current transmit power. After receiving the power calibration frame sent by the access point, the station adjusts the uplink transmit power according to the target received power and the current transmit power carried in the power calibration frame, so that the received power of the access point on different subcarriers or subchannels is pre- Set the difference within the range.

In this embodiment, the station receives the power calibration frame sent by the access point, and adjusts the uplink transmit power according to the target received power and the current transmit power carried in the power calibration frame, so that the access point is in different subcarriers or sub The received power on the channel is within a preset difference range; thus, the difference in uplink transmit power of each station in the WLAN received by the access point is small, and the interference between users is reduced, so that the uplink data can be better received. .

Referring to FIG. 2, FIG. 2 is another flowchart of an uplink transmit power calibration method according to an embodiment of the present invention. In the present embodiment, the site is taken as a main body for explanation. As shown in FIG. 2, the method may include the following steps.

201. Receive a power calibration frame sent by the access point.

The access point sends a power calibration frame to each station in the WLAN, and the access point may send a power calibration frame to each station in the WLAN, and may also broadcast the power calibration frame in the WLAN, which is not limited by the present invention; The power calibration frame includes a target received power and a current transmit power.

The station receives a power calibration frame sent by the access point.

202. Measure the received power of the received power calibration frame of the local station, and according to the received power and The current transmit power calculates the path loss of the site to the access point.

After receiving the power calibration frame sent by the access point, the station receives the received power of the power calibration frame, and calculates the path loss of the site to the access point according to the received power and the current transmit power carried in the power calibration frame. specific:

Path loss = current transmit power - receive power.

203. Calculate a target transmit power according to the target received power and the path loss.

After calculating the path loss from the local end to the access point, the station calculates its desired target transmit power based on the target received power and path loss. Specifically:

Target transmit power = target receive power + path loss.

204. Calculate an uplink transmit power according to the target transmit power, the transmit bandwidth, and the transmit bandwidth of the local station. Where the transmission bandwidth includes the local transmission bandwidth and the transmission bandwidth of the access point.

The station calculates the uplink transmit power based on the target transmit power. The transmit bandwidth of the site and the transmit bandwidth of the access point are known and stored locally in advance. Specifically:

Uplink transmit power = target transmit power X The transmit bandwidth of this site / the transmit bandwidth of the access point.

205. Determine whether the uplink sending power is greater than a preset threshold value of the site.

The uplink transmit power calculated by the station in step 204 may be greater than the preset threshold value of the site. If it is greater than, the site cannot use the uplink transmit power to send uplink data. It can be the upper limit of the sending limit of the site or the power limit of the regulation, or other preset power. Therefore, after calculating the uplink transmit power, it is necessary to determine whether the uplink transmit power is greater than the preset threshold of the site. If the uplink transmit power is greater than the preset threshold value of the local station, step 206 is performed. If the transmit power of the row is not greater than the threshold value preset by the site, step 207 is performed.

206. Perform uplink data transmission by using the preset threshold value of the site as the uplink transmission power.

If it is determined in step 205 that the uplink transmission power is greater than a threshold value preset by the station, the uplink threshold is used as the uplink transmission power for uplink data transmission.

207. Send uplink data by using uplink sending power. If it is determined in step 205 that the uplink transmission power is not greater than a preset threshold value of the local station, the uplink transmission power calculated in step 204 is used to transmit the uplink data.

In a practical application, in a scenario where the coverage of the base station subsystem is large, the target transmission power calculated in step 203 may be different for a station that is closer to the access point and a site that is farther from the access point. To ensure that the performance of the near-end site is optimal, the uplink transmit power of the remote site may exceed a preset threshold, such as a transmission upper limit or a regulatory limit power. Conversely, if the uplink transmit power of the remote site is not exceeded, If the threshold is set, the performance of the near-end site may be poor. This is because the access point can only choose a smaller one to ensure that the uplink transmit power of the remote site does not exceed the preset threshold. The target receives power, so that only the lower modulation scheme can be selected for the near-end station.

Therefore, it is necessary to try to allow the station to fine-tune the calculated uplink transmit power to solve the above problem. In actual operation, the access point does not require the uplink transmit power of all the stations received to be completely consistent, allowing a dynamically changing range. Therefore, the station can fine-tune the uplink transmit power within the range allowed by the access point. In another embodiment, the power calibration frame further includes a power dynamic range indicator field, and the station may fine-tune the uplink transmit power according to the power dynamic range indicator field. The power dynamic range indicator field may be indicated in the power calibration frame, or may be indicated by an element in the beacon frame, which is not limited by the present invention.

If it is determined in step 205 that the uplink transmit power is not greater than a preset threshold value of the local station, the value of the transmit power dynamic range indication field and the target transmit power is added, which is preset with the site. The minimum value after comparison between the threshold values is used as the uplink transmission power after the fine adjustment to perform uplink data transmission. Of course, in practical applications, the station may also select an appropriate power as the uplink transmit power according to the requirements of the uplink modulation and coding mode, and the present invention does not limit the present invention.

Therefore, by allowing the station to fine-tune the uplink transmit power, higher transmit power and higher modulation coding can be used at sites that are closer to the access point of the access point, thereby achieving better performance, for example, more Good throughput.

In practical applications, if the access point is set in the power calibration frame, the target receiving power is biased. Larger, the transmission power required by the station farther away from the access point is too large, exceeding the maximum allowed transmission power, and thus cannot be successfully accessed; if the target reception power is set too small, it is closer to the access point. The site can only use a lower modulation coding mode, and the throughput is reduced to achieve the best performance.

In another embodiment, before performing the step 201, the station first sends the current grouping parameter to the access point, where the grouping parameter includes the distance or path loss of the site to the access point; after the access point receives the grouping parameter, According to the grouping parameter, the stations of the wireless local area network are grouped, and only one group of station access channels are set at a time, and the target receiving power is set for each group, and then the power calibration frame is sent to all stations in the wireless local area network, and the power calibration frame is sent. The target receiving power, the current sending power, and the grouping information are included, and the grouping information includes a station identifier and a group number, where the station identifier, the group number, and the target receiving power correspond to each other. Of course, the packet information can also be sent separately and not included in the power calibration frame. When transmitted separately, the packet information includes the identifier of the station included in the packet, the packet number, and the corresponding target received power.

The station receives the group information returned by the access point, and saves the group information locally. The group information includes the identifier of the station included in each group, the group number of each group, and the corresponding target receiving power. Specifically, the station receives the group information sent by the access point, so that the station groups according to the group information, where the group information includes an identifier of the station included in each group, a group number of each group, and a corresponding target receiving power, so that the station accepts After the power calibration frame sent by the access point, the currently accessed packet is selected according to the target received power carried by the power calibration frame, so that the currently accessed packet adjusts the uplink according to the target received power and the current transmit power carried by the power calibration frame. Transmit power.

Further, when the grouping parameter of the local station changes, the corresponding grouping number is found in the grouping information according to the changed grouping parameter, and then the grouping update request frame is sent to the access point, so that the access point according to the grouping update request The frame updates the packet for the station and returns a packet adjustment frame, wherein the packet update request frame includes a new packet number.

The station receives the packet adjustment frame sent by the access point, where the packet adjustment frame includes a new packet number.

The adjustment group can also be dominated by the access point, specifically:

When the grouping parameters of the site change, the site first sends a new parameter to the access point. For example, when the station detects that the path loss from the local end to the access point needs to be updated, the new path loss is reported to the access point; so that the access point is based on the received new parameter. Point update grouping, specific:

A grouping rule, that is, a grouping parameter and a corresponding grouping number are stored locally at the access point, and the access point searches for a grouping number corresponding to the parameter according to the new parameter as a new grouping number.

After the access point finds the new packet number, it sends a packet adjustment frame to the local station, where the packet adjustment frame includes a new packet number;

The station receives the packet adjustment frame sent by the access point, adjusts the frame update packet according to the packet, and adjusts the uplink transmission power according to the target received power corresponding to the updated packet.

In the foregoing embodiment, the access point control station uses different uplink transmit powers for uplink channel access and uplink data transmission, thereby solving the signal power difference that the access point receives different stations during uplink OFDMA communication. When it is large, it is difficult to receive the uplink data of all stations normally.

However, when the transmission power of the station in the WLAN is different, the problem of the hidden node may be caused. When the uplink transmission power of a certain station is small, the surrounding station may not detect that the station is currently transmitting uplink data. It is considered that the current channel is idle, thereby causing channel access competition.

As shown in Figure 3, the coverage of the API using full power transmission data is circle 1, the coverage of AP2 using full power transmission data is circle 3, the coverage of STA1 using full power transmission data is virtual circle 4, and AP2 is the hidden node of API. If STA1 transmits data with full power, AP2 can hear the signal of STA1, not the hidden node of STA1. However, if STA1 uses the calibrated uplink transmit power for transmission, and the calibrated uplink transmit power is less than its own full power, as shown in circle 2, AP2 cannot hear that STA1 is transmitting data, and considers that the current channel is idle. Using full power to transmit data, this will interfere with the transmission and reception of STA1 uplink data. In order to solve the above problem of the invisible node, the present invention further proposes the following solutions:

Before the station uses the adjusted uplink transmit power for channel access or data transmission, a Request to Send (RTS) frame is sent using standard power to set a suitable Network Allocation Vector (NAV). Access point After receiving the RTS frame, a standard power response compatible channel idle to send (CTS) frame is used, and in the CTS frame, the same NAV domain is also set, and the NAV field is used to indicate a certain period of time for a certain The uplink data transmission of the uplink transmission power station enables all stations that the access point can cover to not transmit data during the period of time, thereby ensuring that the uplink data transmission of the station with a certain uplink transmission power is not affected by other stations. Interference.

Further, the access point in the CTS frame uses the currently unused bit to indicate whether the station performs uplink OFDMA-based channel competition, for example, using a retry bit or a more data bit as an indication bit, for example, the more data bit is 1, indicating that During the above protection period, the station can perform channel competition in the OFDMA mode, and simultaneously perform data transmission with power control, thereby improving spectrum utilization efficiency.

It should be noted that the uplink transmit power calibration method provided in this embodiment may be an OFDMA scenario access, an uplink MU-MIMO scenario, and other non-OFDMA common power control scenarios. .

Referring to FIG. 4, FIG. 4 is another flowchart of an uplink transmit power calibration method according to an embodiment of the present invention. The embodiment is described by using an access point as a main body. As shown in FIG. 4, the method may include the following steps.

401. Send a power calibration frame to each station in the WLAN.

The access point sends a power calibration frame to each station in the WLAN. The power calibration frame includes a target received power and a current transmit power. After receiving the power calibration frame, each station adjusts the uplink transmit power according to the target received power and the current transmit power. Therefore, the difference between the actual receiving power at which the access point receives the uplink data sent by the different stations is within a preset smaller range, thereby achieving the purpose of receiving all user data normally.

402. Receive uplink data sent by each station according to the adjusted uplink transmit power. The station sends the uplink data to the access point using the adjusted uplink transmit power, and the access point receives the uplink data sent by each station according to the adjusted uplink transmit power.

In this embodiment, the access point sends a power calibration frame to each station in the WLAN, so that each station adjusts the transmit power of the local end according to the power calibration frame, so that the access point receives the actual received power of the uplink data sent by different stations. The difference is within a preset smaller range, thereby solving the problem of receiving data sent by different stations during uplink OFDMA communication. When the difference between the actual received powers is too large, it is difficult to receive the user data normally, and the purpose of receiving all user data normally is achieved.

It should be noted that in an optional embodiment of the present invention, the number of sites may be one. At this time, the access point sends a power calibration frame to a station in the WLAN, and receives the station according to the adjusted uplink transmit power. The uplink data sent.

Referring to FIG. 5, FIG. 5 is another flowchart of an uplink transmit power calibration method according to an embodiment of the present invention. The embodiment is described by using an access point as a main body. As shown in FIG. 5, the method may include the following steps.

501. Receive grouping parameters sent by each station.

The access point receives packet parameters transmitted by stations in the wireless local area network, the packet parameters including the distance from each station to the access point or path loss.

502. Group each station according to a grouping parameter, and set only one group of stations to access the channel at a time, and set target receiving power for each group.

The access point receives the packet parameters sent by each station, that is, the distance from each station to the access point or the path loss, and groups each station according to the distance or the path loss, and sets the access point to use only one group of stations at a time. The mode accesses the channel and sets the target received power for each packet, that is, the packet number of each packet is mapped to the target received power setting.

503. The access point sends a power calibration frame to each station in the WLAN.

The access point transmits a power calibration frame to each station in the wireless local area network, the power calibration frame including the station of each packet, the target received power corresponding to each packet, and the current transmit power of the access point. The power calibration frame further includes a power dynamic range indicator field, and the station can fine tune the uplink transmit power according to the power dynamic range indicator field. The power dynamic range indication indication field may be indicated in the power calibration frame, or may be indicated by an element in the beacon frame separately, which is not limited by the present invention.

504. Receive an RTS frame sent by the station.

When the station uses the calibrated uplink transmit power for transmission, and the calibrated uplink transmit power is less than its own full power, the problem of the invisible node may occur. To solve this problem, the RTS/ is introduced in this embodiment. CTS protocol, specifically, first, the station uses standard power to send an RTS frame for setting the appropriate NAV for indicating a period of time. The uplink data transmission of the station transmitting power at a certain uplink, and the access point receives the RTS frame.

505. Return a CTS frame according to the RTS frame.

After receiving the RTS frame sent by the station, the access point uses a standard power response-compatible CTS frame. In the CTS frame, the same NAV field is also set. The NAV field is used to indicate a site for a certain uplink transmit power for a period of time. The uplink data transmission enables all stations that the access point can cover to not transmit data during the period of time, so that the uplink data transmission of the station with a certain uplink transmission power is not interfered by other stations.

506. The access point broadcasts an access group indication frame to a station in the local WLAN to indicate a packet that can currently access the channel.

Because the target receiving power of each packet is different, only one group of stations can access the channel in the same time period to ensure normal reception of uplink data. In step 505, the NAV domain set in the CTS sent by the access point in the WLAN ensures that only one group of stations can access the channel for uplink data transmission within the time period specified by the NAV domain. The access point broadcasts an access group indication frame to the station in the WLAN to indicate the packet currently accessing the channel, thereby ensuring normal reception of the uplink data of the packet.

507. Receive uplink data sent by each station according to the adjusted uplink transmit power. During the period specified by the NAV domain, the access point receives uplink data sent by each station in a certain packet according to the adjusted uplink transmission power.

508. Determine whether a new site is associated with the access point, or whether there is a change in the grouping parameter of the site, and the packet needs to be replaced.

In the WLAN, there may be a new site associated with the access point or the packet parameters of the site need to be changed at any time. The access point needs to periodically monitor whether a new site is associated with the access point, or whether there is a site. The grouping parameters change and the grouping needs to be replaced.

509. When it is detected that a new site is associated with the access point, the new site is grouped according to the grouping parameters of the new site.

510. When it is detected that the packet parameter of the site in the WLAN needs to be changed, the packet of the site is replaced, and a packet adjustment frame is sent to the site, where the packet adjustment frame includes a new packet number.

511. Send a power calibration frame to the station. When it is detected that a new site is associated with the access point, the new site is grouped according to the grouping parameters of the new site, and then a power calibration frame is sent to the site; when it is detected that the packet parameters of the site in the WLAN are changed, When a packet is replaced, the packet for that site is replaced and a power calibration frame is sent to the site.

It should be noted that in an alternative embodiment of the present invention, the number of sites may be one, and at this time, the access point performs the above data exchange with a single site.

In practical applications, if the target receiving power set by the access point in the power calibration frame is too large, the transmission power required by the station farther from the access point is too large, exceeding the maximum allowed transmit power, and thus cannot be successful. Access; If the target receiving power is set too small, the station closer to the access point can only use the lower modulation and coding mode, and the throughput is reduced, and the best performance cannot be achieved.

Further, if the access point uses the power control technology for downlink data transmission, the standard power is used to send a compatible request sending frame to the station, and after receiving the request sending frame, the station sends a frame according to the request, and the compatible channel is idle, and the frame can be sent. The request sending frame includes a network allocation vector; the channel returned by the access point receiving station may send a frame to ensure downlink data transmission of a packet within a time indicated by the network allocation vector, where the channel idle may send the frame including Network allocation vector.

In another embodiment, the access point divides the target received power into several levels before transmitting the power calibration frame, and then sends a power calibration frame containing different target received powers according to a certain rule, in a certain level of target received power. After the power calibration frame is transmitted, only the station whose uplink transmission power is lower than the preset threshold of the site can participate in channel competition and access before the next power calibration frame is transmitted. According to this method, when the target receiving power is small, the remote station can access, and if the near-end station accesses, only the lower transmitting power and modulation coding mode can be used, and the efficiency is low. When the target receiving power is large, the remote station cannot access, and the near-end station can use a higher transmission power and modulation coding mode, and the spectrum utilization efficiency is higher. All stations that can be accessed under a certain target receiving power are grouped together, and since stations closer to the access point can access under different target receiving power settings, they can be included in multiple groups. Under this mechanism, it is ensured that the station far away from the access point has the opportunity to access, and the success rate of the site access farther from the access point is improved. However, according to the above grouping method, stations farther from the access point can only be included in fewer groups, and the probability of access is smaller than that of the near-end station. In another embodiment, the access of the station that is closer to the access point when the target receiving power is smaller is restricted. For example, the access point may carry an uplink sending power lower limit in the power calibration frame, and the station calculates the uplink sending of the local end. When the power is less than the lower limit of the uplink transmit power, the station is not allowed to access the channel. This improves spectrum utilization efficiency while also increasing fairness between sites that are farther away from the access point and sites that are closer to the access point.

In this embodiment, the access point sends a power calibration frame to each station in the WLAN, so that each station adjusts the transmit power of the local end according to the power calibration frame, so that the access point receives the actual received power of the uplink data sent by different stations. The difference is within a preset smaller range, thereby solving the problem that it is difficult to receive the user data normally when the difference between the actual received powers of the data transmitted by different stations is too large during the uplink OFDMA communication, and the normal reception is possible. The purpose of all user data. Further, the stations in the WLAN are grouped, and different target receiving powers are set for each group, so as to solve the problem that the uplink transmission power calculated by the station according to the power calibration frame may exceed the maximum running transmission power and affect the transmission of the uplink data. . Furthermore, the introduction of power control may bring about a new hidden node problem. By introducing the RTS/CTS protocol, by transmitting an RTS/CTS frame carrying the NAV domain to avoid a certain group from transmitting uplink data, other packets are also performing data. Transfer, so you can avoid hidden node problems.

The invention will now be described in more detail by way of a specific application. Please refer to FIG. 6. FIG. 6 is a flowchart of an uplink transmit power calibration method according to an application example of the present invention. As shown in Figure 6, the method is specific:

For example, in the WLAN of this application example, one access point and n-1 stations are set, and the numbers are from the station 1 to the station n-1. Both the access point and the n-1 sites have uplink and downlink data exchange. In this application example, for the convenience of description, only the uplink and downlink data exchange between the site 1 and the access point is intercepted for specific description. Each station in the WLAN first sends a packet parameter to the access point, which may be the path loss between the site to the access point or the distance between the site and the access point.

2. Receive grouping parameters and group each site according to grouping parameters.

The access point receives the grouping parameters of each station, and groups each station according to the grouping parameters, for example, the path loss is grouped within 50 db, and the path loss is grouped between 50 db and 70 db, and the grouping rule can be grouped. Set according to the actual situation, there is no limit here.

3. Transmit power calibration frame.

The access point broadcasts a power calibration frame to all stations, wherein the power calibration frame includes a station including each packet, a target received power corresponding to each packet, and a current transmit power of the access point. The power calibration frame further includes a power dynamic range indicator field, and the station can fine-tune the uplink transmit power according to the power dynamic range indicator field. The power dynamic range indicator field may be indicated in the power calibration frame, or may be indicated by an element in the beacon frame, which is not limited by the present invention.

The access point schedules each packet in turn according to a preset rule for uplink access. The access point may also first broadcast packet information for all stations and the target received power for each packet, and then transmit a power calibration frame to indicate which packet can access the channel.

4. Receive a power calibration frame and calculate the uplink transmit power.

Site 1 receives the power calibration frame and calculates the uplink transmit power. Specifically:

First, after receiving the power calibration frame sent by the access point, the station 1 measures the received power of the power calibration frame, and calculates the site to the access point according to the received power and the current transmit power carried in the power calibration frame. Road loss, specific:

Path loss = current transmit power - receive power.

Then, after calculating the path loss from the local end to the access point, the station 1 calculates the target transmission power that it wants according to the target receiving power and the path loss, specifically:

Target transmit power = target receive power + path loss.

Finally, the station 1 calculates the uplink transmission power based on the target transmission power, and the transmission bandwidth of the site and the transmission bandwidth of the access point are known and stored in advance, specifically: uplink transmission power = target transmission power X. Transmission bandwidth / access point Send bandwidth.

5. Send an RTS frame.

When the station uses the calibrated uplink transmit power for transmission, and the calibrated uplink transmit power is less than its own full power, the problem of the invisible node may occur. To solve this problem, the RTS/ is introduced in this embodiment. The CTS protocol, specifically, first, the station uses the standard power to send an RTS frame for setting an appropriate NAV for indicating the uplink data transmission of the station for a certain uplink transmission power for a period of time.

6. Return the CTS frame.

7. Broadcast an access group indication frame is used to indicate the packet currently accessible to the channel.

Because the target receiving power of each packet is different, only one group of stations can access the channel in the same time period to ensure normal reception of uplink data. Before all preparations are made for channel access, the access point broadcasts an access group indication frame to indicate the packet currently accessible to the channel.

8. Determine whether the uplink transmit power is greater than a preset threshold value of the site.

The uplink transmit power calculated in step 4 may be greater than the preset threshold value of the site. If it is greater than, the site cannot use the uplink transmit power to send uplink data. The threshold may be The sending limit of the site or the regulation limit power, or other preset power; therefore, after calculating the uplink transmit power, it is necessary to determine whether the uplink transmit power is greater than the preset threshold of the site, if the uplink If the transmit power is greater than the preset threshold of the site, the uplink threshold is used as the uplink transmit power for the uplink data transmission. If the uplink transmit power is not greater than the preset threshold of the site. The value is used to transmit uplink data using the calculated uplink transmit power.

In a practical application, in a scenario where the coverage of the base station subsystem is large, the target transmission power calculated by the station according to the power calibration frame is closer to the site and distance from the access point. The sites with farther access points may be different. If the performance of the near-end site is optimized, the uplink transmit power of the remote site may exceed a preset threshold, such as the upper limit of transmission or the power limit. If the uplink transmit power of the remote site does not exceed the preset threshold, the performance of the near-end site may be poor, because the uplink transmit power of the remote site does not exceed the preset threshold. For the limit, the access point can only select a smaller target receive power, so that only the lower modulation coding mode can be selected for the near-end station.

Therefore, it is necessary to try to allow the station to fine-tune the calculated uplink transmit power to solve the above problem. In actual operation, the access point does not require the uplink transmit power of all the stations received to be completely consistent, allowing a dynamically changing range. Therefore, the station can fine-tune the uplink transmit power within the range allowed by the access point. The specific solution is that the power calibration frame also carries a power dynamic range indication field, and the station can fine-tune the uplink transmit power according to the power dynamic range indication field. The power dynamic range indicator field may be indicated in the power calibration frame, or may be indicated by an element in the beacon frame, which is not limited by the present invention.

If the station determines that the uplink transmit power is not greater than a preset threshold of the site, the value of the transmit power dynamic range indication field and the target transmit power is added, and the threshold set by the site is preset. The minimum value after comparison between the values is used as the uplink transmission power after the fine adjustment to perform uplink data transmission. Of course, in an actual application, the station may also select an appropriate power as the uplink transmit power according to the requirement of the uplink modulation and coding mode, which is not limited by the present invention.

9.1. Use the preset threshold value of this site as the uplink transmit power to send the uplink data.

If it is determined in step 8 that the uplink transmission power is greater than a threshold value preset by the station, the uplink data is transmitted using the threshold value preset by the station as the uplink transmission power. 9.2. Use the uplink transmit power to send uplink data. For the threshold value preset in the site, the uplink data is transmitted using the uplink transmission power or the fine-tuned uplink transmission power.

10. Receive uplink data.

The access point receives uplink data sent by each station in the packet of the current access channel.

11. Site n sends the packet parameters.

The new associated site n sends the packet parameters to the access point.

12. Determine if a new site is associated with the access point.

The access point determines if a new site is associated with the access point.

13. Send a power calibration frame after grouping.

The access point receives the packet parameters sent by the new associated site n, and determines that a new site is associated with the access point, and groups the newly associated sites according to the received grouping parameters, and sends a power calibration frame to the station n, the power The calibration frame includes the site of each packet, the target received power corresponding to each packet, and the current transmit power of the access point. The power calibration frame further includes a power dynamic range indicator field, and the station can fine tune the uplink transmit power according to the power dynamic range indicator field. The power dynamic range indicator field may be indicated in the power calibration frame, or may be indicated by an element in the beacon frame, which is not limited by the present invention.

14. Site 1 sends the updated packet parameters.

Site 1 detects changes to the packet parameters of the site and sends the updated packet parameters to the access point.

15. Determine whether there is a change in the grouping parameters of the site.

The access point determines if there is a change in the grouping parameters of the site and needs to be replaced.

16. Transmit the power calibration frame after replacing the packet.

After receiving the updated packet parameters sent by the station 1, the access point determines that the station 1 needs to replace the packet, replaces the station 1 with the packet, and transmits a new packet power calibration frame, where the power calibration frame includes each grouped station, each The target received power corresponding to the packet and the current transmit power of the access point. The power calibration frame further includes a power dynamic range indicator field, and the station may fine-tune the uplink transmit power according to the power dynamic range indicator field. Among them, power dynamics The range indication field may be indicated in the power calibration frame or may be indicated by a single element in the beacon frame, which is not limited in the present invention.

In the above application example, the manner in which packets are displayed is used, that is, each station knows which packet the site belongs to. The access point can achieve the same effect by using the invisible grouping method. Specifically, the access point divides the target receiving power into several levels before transmitting the power calibration frame, and then sends a power calibration frame containing different target receiving powers according to a certain rule. After the power calibration frame containing a certain level of target received power is transmitted, only the station whose uplink transmit power is less than the preset threshold of the site can participate in channel competition and access before the next power calibration frame is transmitted. According to this method, when the target receiving power is small, the remote station can access, and if the near-end station accesses, only the lower transmitting power and modulation coding mode can be used, and the efficiency is low. When the target receiving power is large, the remote station cannot access, and the near-end station can use a higher transmission power and modulation and coding mode, and the spectrum utilization efficiency is higher. All stations that can be accessed under a certain target receiving power are grouped together, and since stations closer to the access point can access under different target receiving power settings, they can be included in multiple groups. Under this mechanism, it is ensured that the station far away from the access point has the opportunity to access, and the success rate of the site access farther from the access point is improved.

However, according to the above grouping method, stations farther from the access point can only be included in fewer groups, and the probability of access is smaller than that of the near-end station. In another embodiment, the access of the station that is closer to the access point when the target receiving power is smaller is restricted. For example, the access point may carry an uplink sending power lower limit in the power calibration frame, and the station calculates the uplink sending of the local end. When the power is less than the lower limit of the uplink transmit power, the station is not allowed to access the channel. This increases the efficiency of spectrum utilization while also increasing the fairness between stations that are farther away from the access point and those that are closer to the access point.

Referring to FIG. 7, FIG. 7 is a schematic diagram of a logical structure of a station according to an embodiment of the present invention. As shown in Figure 7, the site includes:

The power calibration frame receiving module 701 is configured to receive a power calibration frame sent by the access point, and output the signal to the uplink transmit power adjustment module 702, where the power calibration frame includes a target received power and a current transmit power.

An uplink transmit power adjustment module 702, configured to receive power according to the received target and current The transmit power adjusts the uplink transmit power so that the received power of the access point on different subcarriers or subchannels is within a preset difference range.

In this embodiment, the station receives the power calibration frame sent by the access point, and adjusts the uplink transmit power according to the target received power and the current transmit power carried in the power calibration frame, so that the access point is in different subcarriers or sub The received power on the channel is within a preset difference range; thus, the difference in uplink transmit power of each station in the WLAN received by the access point is small, so that the uplink data can be better received.

Referring to FIG. 8, FIG. 8 is a schematic diagram of another logical structure of a station according to an embodiment of the present invention. As shown in Figure 8, the site includes:

The grouping parameter sending module 801 is configured to send a current grouping parameter to the access point, enable the access point to generate a grouping information according to the grouping parameter, and set a target receiving power for each group, where the grouping parameter includes Distance to the access point or path loss.

The group information receiving module 802 is configured to receive group information sent by the access point, so that the station performs grouping according to the group information, where the group information includes an identifier of a station included in each group, a group number of each group, and a corresponding target receiving power; After the station accepts the power calibration frame sent by the access point, the currently accessed packet is selected according to the target received power carried by the power calibration frame, so that the currently accessed packet is based on the target received power and the current transmit power carried by the power calibration frame. Adjust the uplink transmit power.

The power calibration frame receiving module includes:

The measuring unit 8031 is configured to measure the received power of the power calibration frame received by the local station, calculate a path loss of the station to the access point according to the received power and the current transmit power, and output the signal to the target transmit power calculation unit 8032. .

The target transmission power calculation unit 8032 is configured to calculate the target transmission power according to the target reception power and the path loss, and output it to the uplink transmission power calculation unit 8033.

The uplink transmit power calculation unit 8033 is configured to calculate the uplink transmit power according to the target transmit power and the transmit bandwidth, where the transmit bandwidth includes the local transmit bandwidth and the transmit bandwidth of the access point, and output the uplink transmit power to the uplink transmit power adjustment module 804.

The uplink transmit power adjustment module 804 is configured to adjust the uplink transmit power according to the received target received power and the current transmit power, and output the uplink transmit power to the uplink transmit power fine adjustment module 805 to The received power of the access point on different subcarriers or subchannels is within a preset difference range. Further, the power calibration frame further includes a power dynamic range indicator field; the site in this embodiment further includes:

The uplink transmit power fine-tuning module 805 is configured to fine-tune the uplink transmit power according to the power dynamic range change indication field, so that the site uses the fine-adjusted uplink transmit power to perform uplink data transmission.

Further, the site in this embodiment further includes:

The packet search module 806 is configured to search for a corresponding packet number according to the changed packet parameter when the packet parameter of the local station changes, and output to the update frame sending module 807.

The update frame sending module 807 is configured to send a packet update request frame to the access point, where the packet update request frame includes a new packet number.

The packet update acknowledgement frame receiving module 808 is configured to receive a packet update acknowledgement frame sent by the access point.

Further, the site in this embodiment further includes:

The new parameter sending module 809 is configured to: when the packet parameter of the local station changes, send a new parameter to the access point, so that the access point updates the group according to the received new parameter, and sends the packet to the local The station transmits a packet adjustment frame, where the packet adjustment frame includes a new packet number.

The packet update module 810 is configured to receive a packet adjustment frame sent by the access point, and adjust the frame update packet according to the packet.

It should be noted that the modules 806, 807, 808, and 809 and 810 in the dotted line frame in FIG. 8 are functional modules corresponding to the two methods of the site-side master switching packet and the access point-side master switching packet. In practical applications, At the same time, only one way is used, ie the module group with only one dashed box is active. The module groups of the two dashed boxes can exist at the same time, but the module group with only one dashed box at the same time is active.

Further, the site in this embodiment further includes:

The request sending frame sending module 811 is configured to send a compatible request sending frame to the access point, so that the access point sends a frame according to the request to return a compatible channel idle to send a frame, where the request sending frame includes a network allocation vector.

The channel idle may send a frame receiving module 812, configured to receive the channel returned by the access point. The frame can be transmitted to ensure uplink data transmission of a certain packet within a time indicated by the network allocation vector, wherein the channel idle transmission frame includes a network allocation vector.

In this embodiment, the station receives the power calibration frame sent by the access point, and adjusts the uplink sending power according to the target received power and the current transmit power carried in the power calibration frame, so that the access point is on different subcarriers or subchannels. The received power is within a preset difference range; so that the uplink transmit power difference of each station in the WLAN received by the access point is small, so that the uplink data can be better received. And by grouping the stations into the channels separately, to avoid the sites that are too far away from the access point to access the channel at the same time, so that the data can be better received.

Referring to FIG. 9, FIG. 9 is a schematic diagram showing the logical structure of an access point according to an embodiment of the present invention. As shown in Figure 9, the access point includes:

The power calibration frame sending module 901 is configured to send a power calibration frame to a station in the WLAN, so that the station adjusts the uplink sending power according to the target receiving power and the current sending power carried by the power calibration frame, so that the access point receiving station sends the uplink. The difference in the actual received power of the data is within a preset range.

The uplink data receiving module 902 is configured to receive uplink data sent by each station according to the adjusted uplink sending power.

In this embodiment, the access point sends a power calibration frame to each station in the WLAN, so that each station adjusts the transmit power of the local end according to the power calibration frame, so that the access point receives the actual received power of the uplink data sent by different stations. The difference is within a preset smaller range, thereby solving the problem that it is difficult to receive the user data normally when the difference between the actual received powers of the data transmitted by different stations is too large during the uplink OFDMA communication, and the normal reception is possible. The purpose of all user data.

Referring to FIG. 10, FIG. 10 is a schematic diagram of another logical structure of an access point according to an embodiment of the present invention. As shown in Figure 10, the access point includes:

The setting module 1001 is configured to set a plurality of target receiving powers, and divide the target receiving power into several levels.

The transmit power lower limit broadcast module 1002 is configured to broadcast a lower limit of the transmit power of the broadcast station in the wireless local area network, thereby setting a station that rejects the uplink transmit power to be lower than the lower limit of the transmit power. Channel access.

The grouping parameter receiving module 1003 is configured to receive the grouping parameters sent by each station, and output the parameters to the grouping module, and output to the grouping module 1004, where the grouping parameters include the distance from the site to the access point or the path loss.

The grouping module 1004 is configured to group each station according to distance or path loss, set only one group of station access channels each time, and set target receiving power for each group.

It should be noted that the 1001 and 1002 modules and the 1003 and 1004 modules in the dashed box are two ways to group stations in the WLAN. The 1001 and 1002 modules are modules corresponding to the implicit grouping mode, and the 1003 and 1004 modules are displayed. The module corresponding to the grouping mode, at the same time, the access point uses only one grouping mode, that is, the 1001, 1002 modules and the 1003, 1004 modules in the dotted line frame can exist at the same time, but at the same time, only one group of modules is active. State.

The power calibration frame sending module 1005 is configured to send, to the station, a power calibration frame that includes different target received powers, so that after the power calibration frame including a certain target received power is transmitted, the next power including another target received power Before the calibration frame is transmitted, the station whose uplink transmission power is smaller than the maximum allowable transmission power of the station can compete for access to the channel.

The uplink data receiving module 1009 is configured to receive uplink data sent by each station according to the adjusted uplink sending power.

Further, the access point further includes:

The RTS frame receiving module 1006 is configured to receive an RTS frame sent by the station, where the RTS frame includes a network allocation vector.

The CTS frame sending module 1007 is configured to send a frame according to the RTS frame return channel idle to ensure uplink data transmission of a certain packet within a time indicated by the network allocation vector, where the CTS frame includes the network allocation vector.

The access group indication frame broadcast module 1008 is configured to broadcast to the station in the local wireless local area network an access group indication frame for indicating a packet currently accessible to the channel, where the access group indication frame includes a packet number.

Further, the access point in this embodiment further includes:

A request sending frame sending module is configured to receive a request sending frame sent by the station, and send the request The frame includes a network allocation vector.

The channel idle may send a frame module, and the channel returned by the receiving station may send a frame to ensure downlink data transmission of a certain packet within a time indicated by the network allocation vector, wherein the channel idle transmission frame includes a network allocation vector.

Referring to FIG. 11, FIG. 11 is a schematic diagram of still another logical structure of a station according to an embodiment of the present invention. Site 1101 of Figure 11 includes a processor 1201, a memory 1202, and a receiver 1203. The processor 1201, the memory 1202, and the receiver 1203 are connected by a bus system 1204.

The receiver 1203 is configured to receive a power calibration frame sent by the access point, where the power calibration frame includes a target received power and a current transmit power.

The memory 1202 is configured to store an instruction that causes the processor 1201 to: adjust the uplink transmit power according to the target received power and the current transmit power, so that the received power of the access point on different subcarriers or subchannels is at a preset difference. Within the scope.

In addition, the station 1101 may further include a transmitter 1205, an antenna 1206, and the like. The processor 1201 controls the operation of the site 1101. The processor 1201 may also be referred to as a central processing unit (CPU). Memory 1202 can include read only memory and random access memory and provides instructions and data to processor 1201. One of the memories 1202 Portions may also include non-volatile random access memory (NVRAM). In a particular application, receiver 1203 and transmitter 1205 can be coupled to antenna 1206. The various components of the site 1101 are coupled together by a bus system 1204, which may include, in addition to the data bus, a power bus, a control bus, a status signal bus, and the like. However, for clarity of description, various buses are labeled as bus system 1204 in the figure.

The method disclosed in the foregoing embodiments of the present invention may be applied to the processor 1201 or implemented by the processor 1201. Processor 1201 may be an integrated circuit chip with signal processing capabilities. In the implementation process, each step of the above method may be completed by an integrated logic circuit of hardware in the processor 1201 or an instruction in a form of software. The processor 1201 described above may be a general purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), an off-the-shelf programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic device, discrete hardware. Component. The methods, steps, and logic blocks disclosed in the embodiments of the present invention may be implemented or carried out. The general purpose processor may be a microprocessor or the processor or any conventional processor or the like. The steps of the method disclosed in the embodiments of the present invention may be directly implemented as a hardware decoding processor, or may be performed by a combination of hardware and software modules in a decoding processor. The software modules can be located in a conventional storage medium such as random access memory, flash memory, read only memory, programmable read only memory or electrically erasable programmable memory, registers, and the like. The storage medium is located in the memory 1202. The processor 1201 reads the information in the memory 1202 and completes the steps of the above method in combination with the hardware.

Optionally, as an embodiment, the processor 1201 measures the received power of the received power calibration frame, and calculates a path loss to the access point according to the received power and the current transmit power; and calculates the target transmit power according to the target received power and the path loss; The uplink transmit power is calculated according to the target transmit power and the transmit bandwidth, where the transmit bandwidth includes a local transmit bandwidth and a transmit bandwidth of the access point.

Optionally, as an embodiment, the transmitter 1205 sends the current packet parameter to the access point, so that the access point generates the group information according to the grouping parameter, sets the site of the access channel, and sets the target receiving power for each group, and groups the packet. The parameter includes a distance to the access point or a path loss; the receiver 1203 receives the packet information transmitted by the access point such that the processor 1201 performs grouping according to the grouping information, the grouping information including the identifier of the site included in each group, each group Group number And corresponding target receiving power; after receiving the power calibration frame sent by the access point, selecting the currently accessed packet according to the target received power carried by the power calibration frame, so that the currently accessed packet is according to the target carried by the power calibration frame The received power and the current transmit power adjust the uplink transmit power.

Optionally, as an embodiment, the memory 1202 is configured to store an instruction that causes the processor 1201 to: when the grouping parameter changes, find a corresponding group number according to the changed grouping parameter. The transmitter 1205 is configured to send a packet update request frame to the access point, where the packet update request frame includes a new packet number, and a receiver 1203, configured to receive a packet adjustment frame sent by the access point, where the packet adjustment frame includes a new packet number.

Optionally, as an embodiment, the transmitter 1205 is configured to send, by using standard power, a compatible request sending frame to the access point, so that the access point sends a frame according to the request, and the compatible channel is idle, the frame can be sent, and the request sending frame includes The network allocation vector; the receiver 1203, configured to receive the channel returned by the access point to send a frame to ensure uplink data transmission of a certain packet within a time indicated by the network allocation vector, and the channel idle transmission frame includes a network allocation vector.

Referring to FIG. 12, FIG. 12 is still another logical structure diagram of an access point according to an embodiment of the present invention. The access point 1102 of Figure 12 includes a processor 1301, a memory 1302, a transmitter 1305, and a receiver 1303. The processor 1301, the memory 1302, the transmitter 1305, and the receiver 1303 are connected by a bus system 1304.

The transmitter 1305 is configured to send a power calibration frame to the station in the WLAN, so that the station adjusts the uplink sending power according to the target receiving power and the current sending power carried by the power calibration frame, so that the access point receives the actual receiving of the uplink data sent by the station. The difference in power is within a preset range;

The receiver 1303 is configured to receive uplink data sent by the station according to the adjusted uplink transmit power.

In addition, the access point 1102 can also include an antenna 1306. The processor 1301 controls the operation of the access point 1102. The processor 1301 can also be referred to as a central processing unit (CPU). Memory 1302 can include read only memory and random access memory and provides instructions and data to processor 1301. A portion of the memory 1302 may also include non-easy Loss Random Access Memory (NVRAM). In a particular application, receiver 1303 and transmitter 1305 can be coupled to antenna 1306. The various components of the access point 1102 are coupled together by a bus system 1304, which may include, in addition to the data bus, a power bus, a control bus, a status signal bus, and the like. However, for clarity of description, various buses are labeled as bus system 1304 in the figure.

The method disclosed in the foregoing embodiments of the present invention may be applied to the processor 1301 or implemented by the processor 1301. Processor 1301 may be an integrated circuit chip that has signal processing capabilities. In the implementation process, each step of the above method may be completed by an integrated logic circuit of hardware in the processor 1301 or an instruction in a form of software. The processor 1301 described above may be a general purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), an off-the-shelf programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic device, discrete hardware. Component. The methods, steps, and logic blocks disclosed in the embodiments of the present invention may be implemented or carried out. The general purpose processor may be a microprocessor or the processor or any conventional processor or the like. The steps of the method disclosed in the embodiments of the present invention may be directly implemented as a hardware decoding processor, or may be performed by a combination of hardware and software modules in a decoding processor. The software modules can be located in a conventional storage medium such as random access memory, flash memory, read only memory, programmable read only memory or electrically erasable programmable memory, registers, and the like. The storage medium is located in the memory 1302. The processor 1301 reads the information in the memory 1302 and completes the steps of the above method in combination with its hardware.

Optionally, as an embodiment, the memory 1302 is configured to store an instruction that causes the processor 1301 to: set a plurality of target received powers, and divide the target received power into multiple levels; the transmitter 1305 is configured to send the include to the station. A power calibration frame for receiving power of different targets, so that after the power calibration frame containing a certain target received power is transmitted, before the next power calibration frame containing another target received power, the uplink transmit power is less than the maximum allowable transmit power of the station. The site can compete for access to the channel.

Optionally, as an embodiment, the receiver 1303 receives the grouping parameters sent by each station, where the grouping parameters include the distance from the site to the access point or the path loss; and each station is grouped according to the distance or the path loss, and is set each time. Only one set of stations accesses the channel, and sets the target received power for each packet; the power calibration frame also includes the packet number, where the packet number and the target received power One-to-one correspondence.

Optionally, as an embodiment, the memory 1302 is configured to store an instruction that causes the processor 1301 to: when a new site is associated with the access point, group the new site according to a grouping parameter of the new site; 1305 is used to send a power calibration frame to the new station.

Optionally, as an embodiment, the memory 1302 is configured to store an instruction that causes the processor 1301 to: replace the grouping of the site when it is detected that a packet parameter of a site in the wireless local area network changes needs to be replaced. Transmitter 1305 sends a packet adjustment frame to the station, the packet adjustment frame including the new packet number.

Optionally, as an embodiment, the receiver 1303 is configured to receive a request sending frame sent by the station, where the request sending frame includes a network allocation vector;

The transmitter 1303 is configured to send a frame according to the request to return the channel idle to transmit a frame to ensure uplink data transmission of a certain packet within a time indicated by the network allocation vector, and the channel idle transmission frame includes a network allocation vector. Referring to FIG. 13, FIG. 13 is a schematic diagram of a logical structure of a wireless local area network communication system according to an embodiment of the present invention. As shown in Figure 13, the system includes:

The station 1101 is configured to receive a power calibration frame sent by the access point, where the power calibration frame includes a target received power and a current transmit power, and adjust an uplink transmit power according to the target received power and the current transmit power, so that the The received power of the access point on different subcarriers or subchannels is within a preset difference range;

The access point 1102 is configured to send a power calibration frame to each station in the WLAN, where the power calibration frame includes a target received power and a current transmit power, so that each station adjusts according to the target received power and the current transmit power. Uplink transmission power; receiving uplink data sent by each station according to the adjusted uplink transmission power.

Further, the step of the station 1101 adjusting the uplink transmit power according to the target received power and the current transmit power is specific:

Measuring the received power of the received power calibration frame of the device, and calculating the path loss of the device to the access point according to the received power and the current transmit power;

Calculating the target transmit power of the device according to the target received power and the path loss;

Transmit bandwidth and local design based on target transmit power and pre-stored local access points The transmit bandwidth of the backup calculates the uplink transmit power.

Further, the power calibration frame further includes a power dynamic range indicator field; after adjusting the uplink transmit power according to the power calibration frame, the station is further configured to fine-tune the uplink transmit power according to the power dynamic range indicator field, so that the device The uplink transmission power after the fine adjustment is used for uplink data transmission.

Further, the station 1101 is further configured to send the current grouping parameter to the access point 1102, where the grouping parameter includes a distance or path loss of the device to the access point; and receiving group information returned by the access point, where the grouping information includes each The corresponding group number and target receiving power of the group.

The access point 1102 is further configured to group the stations 1101 according to the grouping parameters, set only one group of station access channels each time, and set the target receiving power for each group.

Further, the site 1101 is further configured to: when the packet parameter of the device changes, find a corresponding packet number according to the changed packet parameter; send a packet update request frame to the access point 1102, where the packet update request frame includes a new one. a packet number; a packet adjustment frame transmitted by the access point 1102, wherein the packet adjustment frame includes a new packet number.

The access point 1102 is further configured to replace the packet of the station 1101 when a packet parameter of the station 1101 changes in the wireless local area network, and send a packet adjustment frame to the station.

Further, the station 1101 is further configured to: when the packet parameter of the device changes, send a new parameter to the access point 1102; receive the packet adjustment frame sent by the access point 1102, and adjust the frame update packet according to the packet.

The access point 1102 is further configured to replace the grouping of the station when the grouping parameter of the station in the wireless local area network needs to be changed, and send the grouping adjustment frame to the station, where the group adjustment frame includes the new group number.

Further, before the access point 1102 sends a power calibration frame to each station in the WLAN, it is also used to set a plurality of target received powers, and divide the target received power into several levels.

The steps of the access point 1102 transmitting power calibration frames to each site in the WLAN are specific:

Sending a power calibration frame containing different target received powers to each station (optionally, to each station in the WLAN in a preset order), so as to include a certain target receiving power After the rate power calibration frame is transmitted, the station whose uplink transmission power is smaller than the maximum allowable transmission power of the station can compete for access to the channel before the next power calibration frame containing another target reception power is transmitted.

Further, the access point sets a plurality of target receiving powers, and sets the target receiving power to set a channel to reject the uplink transmitting power less than the lowering of the sending power.

Further, before the step of transmitting the power calibration frame to each station in the WLAN by the access point 1102, the method further includes receiving, by the station, a packet parameter sent by each station, where the group parameter includes a distance from the station to the access point or a path loss; The distance or path loss determines the grouping of the station, and sets only one group of access channels at a time, and sets the target receiving power for each group; wherein, the power calibration frame further includes a group number, where the group number corresponds to the target receiving power- .

Further, after receiving the uplink data sent by each station according to the adjusted uplink transmission power, the access point 1102 is further configured to group the new station according to the grouping parameter of the new station when a new station is associated with the access point; And send a power calibration frame to the new site.

Further, the station is further configured to send a compatible RTS frame to the access point by using standard power, where the RTS frame includes a network allocation vector; and receive a CTS frame returned by the access point, where the CTS frame includes a network allocation vector.

The access point is further configured to receive an RTS frame sent by the station; and then return a CTS frame according to the RTS frame to ensure uplink data transmission of a packet within a time indicated by the network allocation vector, where the CTS frame includes a network allocation vector.

Further, the access point is further configured to send a compatible RTS frame to the station by using standard power, where the RTS frame includes a network allocation vector; and receive a CTS frame returned by the access point, where the CTS frame includes a network allocation vector.

The station is further configured to receive an RTS frame sent by the access point, and then return a CTS frame according to the RTS frame to ensure downlink data transmission of a packet within a time indicated by the network allocation vector, where the CTS frame includes a network allocation vector.

Further, the access point is further configured to broadcast, to the station in the local wireless local area network, an access group indication frame, which is used to indicate a packet that can currently access the channel, where the access group indication frame includes a packet number. It should be noted that, in the wireless local area network communication system provided by this embodiment,

The OFDMA scenario access can also be an uplink MU-MIMO scenario, and other non-OFDMA mode common power control scenarios, which are not limited herein.

Moreover, in an alternative embodiment of the present invention, the wireless local area network communication system of the present invention may also include the station described in FIG. 4 or FIG. 5 and the access point described in FIG. 7 or FIG.

In the several embodiments provided in the present application, it should be understood that the disclosed system, apparatus, and method may be implemented in other manners. For example, the device implementations described above are merely illustrative. For example, the division of the modules or units is only a logical function division. In actual implementation, there may be another division manner, for example, multiple units or components may be used. Combined or can be integrated into another system, or some features can be ignored, or not executed. In addition, the coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection through some interface, device or unit, and may be electrical, mechanical or otherwise.

The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, may be located in one place, or may be distributed to multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of the present embodiment. In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above integrated unit can be implemented in the form of hardware or in the form of a software functional unit.

The integrated unit, if implemented in the form of a software functional unit and sold or used as a standalone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present application, in essence or the contribution to the prior art, or all or part of the technical solution may be embodied in the form of a software product stored in a storage medium. The instructions are included to cause a computer device (which may be a personal computer, a server, or a network device, etc.) or a processor to perform all or part of the steps of the methods described in various embodiments of the present application. The foregoing storage medium includes: a U disk, a removable hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and the like, which can store program codes. .

Claims

claims

1. An uplink transmit power calibration method, characterized in that it includes the following steps: receiving a power calibration frame sent by an access point, where the power calibration frame includes the target received power and the current transmit power;

The uplink transmit power is adjusted according to the target received power and the current transmit power, so that the received power of the access point on different subcarriers or subchannels is within a preset difference range.

2. The method according to claim 1, wherein the adjusting the uplink transmit power according to the target received power and the current transmit power includes:

Measure the received power when receiving the power calibration frame, and calculate the path loss to the access point based on the received power and the current transmit power;

Calculate target transmit power according to the target receive power and the path loss;

The uplink transmit power is calculated according to the target transmit power and a transmit bandwidth, where the transmit bandwidth includes a local transmit bandwidth and a transmit bandwidth of the access point.

3. The method according to claim 1 or 2, wherein the step of receiving the power calibration frame sent by the access point further includes:

Send the current grouping parameters to the access point, cause the access point to generate grouping information according to the grouping parameters, set the station of the access channel, and set the target received power for each group, and the grouping parameters include The distance to the access point or the path loss;

Receive the grouping information sent by the access point to perform grouping according to the grouping information, where the grouping information includes the identification of the stations included in each group, the grouping number of each group and the corresponding target received power; So that after receiving the power calibration frame sent by the access point, the currently accessed packet is selected according to the target received power carried by the power calibration frame, so that the currently accessed packet is received according to the target carried by the power calibration frame. power and the current transmit power to adjust the uplink transmit power.

4. The method according to claim 3, characterized in that:

When the grouping parameters change, the corresponding grouping number is found according to the changed grouping parameters; Send a packet update request frame to the access point, the packet update request frame including the new packet number;

Receive a packet adjustment frame sent by the access point, where the packet adjustment frame includes a new packet number.

5. The method according to any one of claims 3 to 4, wherein the step of receiving the power calibration frame sent by the access point further includes:

Use standard power to send a compatible request-to-send frame to the access point, so that the access point returns a compatible channel idle frame to send according to the request-to-send frame, and the request-to-send frame includes a network allocation vector;

The channel idle frame returned by the access point is received to ensure uplink data transmission of a certain packet within the time indicated by the network allocation vector, and the channel idle frame includes the network allocation vector.

6. An uplink transmit power calibration method, characterized in that it includes the following steps: sending a power calibration frame to a station in a wireless local area network, so that the station adjusts according to the target received power and the current transmit power carried by the power calibration frame. Uplink transmit power, so that the difference in actual received power of the access point when receiving the uplink data sent by the station is within a preset range;

Receive uplink data sent by the station according to the adjusted uplink transmit power.

7. The method according to claim 6, wherein before the step of sending a power calibration frame to the station in the wireless local area network, the step further includes:

Set multiple target received powers, and divide the target received powers into multiple levels; The sending a power calibration frame to the station in the wireless local area network includes:

Send power calibration frames containing different target received powers to the station, so that after the power calibration frame containing a certain target received power is sent, before the next power calibration frame containing another target received power is sent, the uplink transmission Stations with power less than the station's maximum allowed transmit power can compete for access to the channel.

8. The method according to claim 7, wherein before the step of the access point sending a power calibration frame to the station in the wireless local area network, the step further includes:

Receive the grouping parameters sent by the station, the grouping parameters include the station to the Access point distance or path loss;

Determine the grouping of the stations based on the distance or the path loss, set only one group of stations to access the channel at a time, and set the target received power for each group;

The power calibration frame also includes a group number, where the group number corresponds to the target received power one-to-one.

9. The method according to claim 8, wherein the step of receiving the uplink data sent by the station according to the adjusted uplink transmit power further includes:

When a new site is associated with the access point, group the new sites according to the grouping parameters of the new site;

Send a power calibration frame to the new station.

10. The method according to claim 9, wherein the step of receiving the uplink data sent by the station according to the adjusted uplink transmit power further includes:

When it is detected that the grouping parameters of a station in the wireless local area network have changed and the grouping needs to be replaced, the grouping of the station is replaced and a grouping adjustment frame is sent to the station, where the grouping adjustment frame includes a new grouping number.

11. The method according to claim 10, wherein the step of sending a power calibration frame to the station in the wireless local area network further includes:

Receive a request to send frame sent by the station, where the request to send frame includes a network allocation vector;

According to the request to send a frame, a channel idle frame can be sent to ensure the uplink data transmission of a certain group within the time indicated by the network allocation vector, and the channel idle frame can be sent including the network allocation vector.

12. A site, characterized by: including:

A power calibration frame receiving module, configured to receive a power calibration frame sent by the access point, where the power calibration frame includes the target received power and the current transmit power;

An uplink transmit power adjustment module, configured to adjust the uplink transmit power according to the target received power and the current transmit power, so that the received power of the access point on different subcarriers or subchannels is within a preset difference range Inside.

13. The station according to claim 12, characterized in that, the power calibration frame The receiving module includes:

A measuring unit, configured to measure the received power when receiving the power calibration frame, and calculate the path loss to the access point based on the received power and the current transmit power;

A target transmit power calculation unit, configured to calculate the target transmit power according to the target receive power and the path loss;

An uplink transmit power calculation unit, configured to calculate the uplink transmit power according to the target transmit power and a transmission bandwidth, where the transmission bandwidth includes a local transmission bandwidth and a transmission bandwidth of the access point.

14. The site according to any one of claims 12 to 13, characterized in that the site further includes:

A grouping parameter sending module, configured to send the current grouping parameters to the access point, so that the access point generates grouping information according to the grouping parameters, sets the station of the access channel, and sets the target reception for each grouping. Power, the grouping parameter includes the distance to the access point or the path loss;

A grouping information receiving module, configured to receive the grouping information sent by the access point so that the uplink transmission power calculation unit performs grouping according to the grouping information, where the grouping information includes the identification of the stations included in each group, The group number of each group and the corresponding target received power; so that after receiving the power calibration frame sent by the access point, the uplink transmit power adjustment module selects the current target received power according to the target received power carried by the power calibration frame. The accessed packet, thereby causing the currently accessed packet to adjust the uplink transmit power according to the target receive power and the current transmit power carried in the power calibration frame.

15. The site according to claim 14, characterized in that, the site further includes: a grouping search module, when the grouping parameters change, the corresponding grouping number is found according to the changed grouping parameters;

An update frame sending module, configured to send a group update request frame to the access point, where the group update request frame includes a new group number;

A packet update confirmation frame receiving module, configured to receive a packet adjustment frame sent by the access point, where the packet adjustment frame includes a new group number.

16. The site according to any one of claims 14 to 15, characterized in that: Site also includes:

A request-to-send frame sending module, configured to send a compatible request-to-send frame to the access point using standard power, so that the access point returns a compatible channel-idle-send frame according to the request-to-send frame, where the request-to-send frame includes network allocation vector;

The channel idle frame receiving module is used to receive the channel idle frame returned by the access point to ensure the uplink data transmission of a certain group within the time indicated by the network allocation vector. The channel idle frame can be sent. The frame includes the network allocation vector.

17. An access point, characterized by: including:

A power calibration frame sending module, configured to send a power calibration frame to a station in the wireless local area network, so that the station adjusts the uplink transmit power according to the target receiving power and current transmit power carried by the power calibration frame;

The uplink data receiving module is configured to receive uplink data sent by the station according to the adjusted uplink transmit power so that the access point receives the actual received power difference of the uplink data sent by the station within a preset range.

18. The access point according to claim 17, characterized in that, the access point further includes:

A setting module for setting multiple target received powers and dividing the target received powers into multiple levels;

The power calibration frame sending module is configured to send power calibration frames containing different target received powers to the station, so that after a power calibration frame containing a certain target received power is sent, the next one containing another target received power is sent. Before the power calibration frame is sent, stations whose uplink transmit power is less than the maximum allowed transmit power of the station can compete for the access channel.

19. The access point according to claim 17, characterized in that, the access point further includes:

A grouping parameter receiving module, configured to receive the grouping parameters sent by the station, and output them to the grouping module, where the grouping parameters include the distance or path loss from the station to the access point; the grouping module, used according to the The stations are grouped according to the distance or the path loss, and only one group of stations is set to access the channel at a time, and the target reception power is set for each group; the power calibration frame also includes a group number, where the group number is the same as the target reception Power one pair answer.

20. The access point according to claim 17, characterized in that, the access point further includes:

A grouping module, configured to group the new sites according to the grouping parameters of the new sites when a new site is associated with the access point;

A power calibration frame sending module, configured to send a power calibration frame to the new station.

21. The access point according to claim 17, characterized in that, the access point further includes:

A packet replacement module, configured to, when it is detected that the packet parameters of a station within the wireless local area network have changed and the packet needs to be replaced, replace the packet of the station, and send a group adjustment frame to the station, where the group adjustment frame includes the new Group number.

22. The access point according to claim 17, characterized in that, the access point further includes:

A request-to-send frame receiving module, configured to receive a request-to-send frame sent by the station, where the request-to-send frame includes a network allocation vector;

The channel idle frame sending module is used to send a frame according to the request and return the channel idle frame to ensure the uplink data transmission of a certain group within the time indicated by the network allocation vector. The channel idle frame can be sent. Includes the network allocation vector.

23. A wireless local area network communication system, characterized by comprising the site described in any one of claims 12 to 16 and the access point described in any one of claims 17 to 22.