CN103957586A - Power adjustment method and device for wireless local area network - Google Patents

Abstract

The invention discloses a power adjustment method and device for a wireless local area network. The method includes the steps that the condition of interference on an access point (AP) is obtained through an AP scanning channel, and the degree of interfering other adjacent cell APs by the AP is evaluated according to the condition of interference; a link boundary value of a working station in parallel with the AP is obtained; if the AP has large interference on the other adjacent cell APs, the power of the AP is lowered; if the AP has moderate interference on the other adjacent cell APs, the power of the AP is kept; if the AP has no interference on the other adjacent cell APs, the power of the AP is increased. After interference conditions of all the APs of the whole network are obtained, the degree of interfering the network by the APs is obtained according to all the interference conditions of the APs to determine the AP selection, and the power of the AP is adjusted by referring to the link boundary value of the working station in parallel with the AP, so that the interference on the whole network is reduced, and communication quality of the network is effectively improved.

Description

Power adjustment method and device for wireless local area network

technical field

The invention relates to the technical field of wireless local area networks, in particular to a method and device for adjusting power of a wireless local area network.

Background technique

In recent years, wireless local area network (WLAN, Wireless Local Area Network) has been more and more widely used. This technology is based on the IEEE (International Institute of Electrotechnical and Electronic Engineering) 802.11 standard, which is a series of standards formulated by IEEE. The wireless interface between the access point (AP, Access Point) and the workstation (STA, Station).

The propagation of wireless signals is affected by the surrounding environment, and problems such as multipath will cause complex attenuation phenomena of wireless signals in different directions. Therefore, the implementation of WLAN networks often requires careful network planning. Even after the wireless network is successfully deployed, parameter adjustment in the application stage is still necessary, because the wireless environment is constantly changing, and the interference caused by moving obstacles and working microwave ovens may affect the wireless signal. Propagation is affected, so radio frequency resources such as channels and transmit power must be dynamically adjusted to adapt to changes in the user environment. Such an adjustment process is complicated and requires extensive technical experience and regular manual testing, resulting in very high management costs.

In many current WLAN networks, when the device is initially powered on, the transmit power of each communication device is initially set at a certain predetermined level, such as the maximum transmit power of the device, and is kept at this level throughout the subsequent communication. Set power on. If factors such as the environment change or each network device changes its corresponding location, the transmit power set at initial power-on may become too low or too high, so it is necessary to dynamically adjust the transmit power level in the WLAN environment. The power control in the WLAN network can be divided into STA power control and AP power control: STA power control is based on ensuring the communication quality of users, reducing the STA transmit power as much as possible, reducing STA energy consumption, and prolonging the STA’s working time. Time; the power control of the AP is mainly to complete the coverage of the target space and reduce the interference between APs.

In a high-density WLAN coverage area, there may be many APs and SSIDs (Service SetIdentifier, service identification set), and the interference between them is very serious. Due to the limited number of wireless channels, it is impossible to effectively reduce the interference of the WLAN system in high-density coverage areas only by relying on general channel allocation methods.

Contents of the invention

Based on this, it is necessary to provide a wireless local area network power adjustment method and device for the above problems, so that it can reduce the interference of the WLAN system and improve the performance of the WLAN system by adjusting the transmit power of the AP.

A power adjustment method for a wireless local area network, comprising the steps of:

Obtain the interference situation of the access point by scanning the channel of the access point, and evaluate the interference degree of the access point to other neighboring cell access points according to the interference situation, wherein the interference degree includes large interference, No interference, moderate interference;

Obtaining a link boundary value of a workstation associated with the access point, wherein the link boundary value is determined according to the power value received by the workstation minus the lowest acceptable power value;

If the access point interferes greatly with access points in other neighboring cells, reduce the power of the access point according to the link boundary value and the minimum transmit power limit of the access point;

If the access point interferes moderately with other adjacent cell access points, keep the power of the access point.

A power adjustment device for a wireless local area network, comprising:

An interference degree acquiring module, configured to obtain the interference situation of the access point by scanning channels of the access point, and evaluate the interference degree of the access point to other neighboring cell access points according to the interference situation, wherein the The degree of interference includes large interference, no interference, and moderate interference;

A link boundary value acquisition module, configured to acquire a link boundary value of a workstation associated with the access point, wherein the link boundary value is determined according to the power value received by the workstation minus the lowest acceptable power value;

A power adjustment module, configured to reduce the power of the access point according to the link boundary value and the minimum transmission power limit of the access point when the access point interferes with other adjacent cell access points. Power: keep the power of the access point when the interference of the access point to other neighbor access points is moderate.

The power adjustment method and device of the wireless local area network of the present invention can dynamically select a certain AP in the network and adjust its transmission power through the real-time centralized acquisition of the interference received by the AP in the network and the interference caused to the network. The selection is determined by obtaining the interference degree of APs to the network through all AP interference conditions after obtaining the interference conditions of all APs in the entire network, and adjusting the power of the AP with reference to the link boundary value of the associated workstation of the AP, so that the entire network The interference is reduced and the communication quality of the network is effectively improved.

Description of drawings

Fig. 1 is the schematic flow chart of the method embodiment 1 of the present invention;

Fig. 2 is the schematic flow chart of the second embodiment of the method of the present invention;

Fig. 3 is the schematic flow chart of the third embodiment of the method of the present invention;

Figure 4 is a schematic structural view of Embodiment 1 of the device of the present invention;

Figure 5 is a schematic structural view of Embodiment 2 of the device of the present invention;

Fig. 6 is a schematic structural diagram of Embodiment 3 of the device of the present invention.

Detailed ways

The specific implementation manner of the power adjustment method of the wireless local area network of the present invention will be described in detail below with reference to the accompanying drawings.

As shown in Figure 1, a kind of power adjustment method of wireless local area network, comprises steps:

S110. Obtain the interference situation of the access point by scanning the channel of the access point, and evaluate the interference degree of the access point to other neighboring cell access points according to the interference situation, wherein the interference degree includes relatively high interference Large, no interference, moderate interference;

Scan the channel by the AP to obtain a channel quality report, and build a channel quality assessment table according to the quality report, the channel quality assessment table indicates the interference situation of the AP and the detected neighbor AP information; the content of the channel quality assessment table measurement can include: Whether there is a radar signal in this frequency band, the average RSSI (Received Signal Strength Indication) of received packets, packet error rate, detected interference value (interference time/total communication time), neighbor AP to this AP The interference situation and the load situation of the AP channel, etc.;

Obtain the channel quality evaluation table of each AP, then can obtain the interference situation evaluation table by the channel quality evaluation table processing of all APs, and the interference situation evaluation table represents the interference degree of the AP to other neighboring APs; the interference situation evaluation table can include : AP identification number, AP radio frequency module identification number, AP working channel number, total interference degree to other neighboring APs (large interference, moderate interference, no interference, etc.), interfered AP identification number, interfered AP working channel number, the interference value of the AP to the interfered AP (the time the interference signal occupies the channel/total data communication time), the interference value of the AP-associated STA to the interfered AP, and the interference intensity of the interfered AP (the average RSSI of the received interference signal) and interference level (the degree of interference of the AP to the interfered AP), etc., wherein the identification number and the working channel number are AP attributes, indicating the identity information of the AP and the working channel number, and the AP radio frequency module identification number indicates the radio frequency module number of the AP;

S120. Obtain a link boundary value of a workstation associated with the access point, wherein the link boundary value is determined according to the power value received by the workstation minus the lowest acceptable power value;

The 802.11h protocol stipulates that the STA can collect the TPC (Transmit Power Control, transmit power control) Report information element, which contains the transmit power of this frame and the link margin (link margin) value, that is, the safety limit value proposed by the workstation ;The link boundary value is the received power value (dBm) minus the lowest acceptable value (dBm);

Currently, the AP periodically sends a TPC Request frame to the STA, and the STA responds with a TPC Report frame and a Link margin value to build a list of STA's link margin values;

S130. If the access point interferes significantly with access points in other neighboring cells, reduce the power of the access point according to the link boundary value and the minimum transmit power limit of the access point, wherein the minimum transmit Power is an inherent attribute of each AP, that is, the minimum transmit power value that the AP can provide;

S140. If the access point interferes moderately with access points of other neighboring cells, maintain the power of the access point.

When the access point has no interference with other neighboring cell access points, there may be a problem that the access point transmits less power. In order to better improve the network quality, in one embodiment, the embodiment of the present invention may also include the steps :

If the access point has no interference with other neighboring cell access points, increase the power of the access point according to the maximum transmit power limit of the access point, wherein the maximum transmit power is an inherent attribute of each AP, That is, the maximum transmit power value that the AP can provide, which is usually set as a parameter configuration.

In step S110, the degree of interference of the access point to other neighboring cell access points is evaluated according to the interference situation, that is, the interference situation evaluation table is obtained according to the channel quality evaluation table, which can be implemented according to known methods in the prior art, for example, in a In an embodiment, the process of establishing the interference situation evaluation table according to the channel quality evaluation table may include:

After updating the channel quality evaluation table of AP_0 (currently analyzed interfering AP), trigger the N same-frequency neighbor AP_i (i=1,2,3...,N) recorded in its channel quality evaluation table to update its interference evaluation table ;

Copy the information of AP_i in the AP list of the neighboring cell of AP_0 to the interference evaluation table of AP_i, and replace the table header with AP_0;

Add a time stamp to entry AP_0 in the interference situation assessment table for AP_i;

Calculate the interference level of AP_i and record it in the bit corresponding to item AP_0 in the interference evaluation table of AP_i;

After updating the interference evaluation tables of the N co-frequency neighboring cells AP_i, evaluate the interference degree of AP_0 to all neighboring cells AP_i.

The steps of calculating the interference level of AP_i include:

Determine whether the interference duration of AP_0 to AP_i is greater than the AP interference duration threshold, if so, consider that the interference to AP_i is relatively large, otherwise go to the next step; wherein the interference duration indicates the length of time the channel is occupied;

Determine whether the RSSI received by AP_0 from AP_0 is greater than the AP interference reception power threshold, if so, consider that the interference to AP_i is relatively large, otherwise go to the next step;

Determine whether the STA associated with AP_0 interferes with AP_i for longer than the STA interference duration threshold. If yes, consider the interference to AP_i to be moderate; otherwise, consider the interference to AP_i to be small.

The steps to evaluate the interference degree of AP_0 to all neighboring cells AP_i include:

S111. Determine whether the interference evaluation table of AP_0 is empty, if it is empty, it means that AP_0 does not cause interference to the neighboring cell AP_i, and proceed to step S117; if it is not empty, it means that AP_0 causes interference to the neighboring cell AP_i, and proceed to step S112;

S112, judging whether there is an interference level of AP_i in the AP_0 interference situation evaluation table, which means that the interference is relatively large, if it is, it means that some neighboring cells AP_i have received relatively large interference, and enter step S113, otherwise enter step S114;

S113, in the interference situation evaluation table of AP_0, the interference level of AP_i is whether the proportion of the interference is not less than the high interference threshold, if it enters step S115, otherwise enters step S116; wherein the ratio refers to the interference level is the interference The ratio of large AP_i to all neighboring AP_i of AP_0;

S114. In the interference situation evaluation table of AP_0, the interference level of AP_i is whether the ratio of the smaller interference is greater than the low interference threshold, if yes, it means that the interference of AP_0 to the periodic neighbor cell AP_i is small, and enter step S117, otherwise, enter step S116; Wherein the ratio refers to the interference level is the ratio of AP_i with less interference to all neighboring cells AP_i of AP_0;

S115. Set the degree of interference of AP_0 to the neighboring cell AP_i as greater interference;

S116: Set the interference degree of AP_0 to the neighboring cell AP_i as moderate interference;

S117: Set the degree of interference of AP_0 to the neighboring cell AP_i as no interference.

When the interference of the AP to the neighboring AP is large, it is necessary to reduce the power of the AP according to the link boundary value and the minimum transmission power limit of the access point. In order to avoid reducing the AP power to cause coverage blindness, in one embodiment In step S130, reducing the AP power may include:

S131. If the link boundary values of each of the workstations have been updated in real time, and the link boundary values are greater than the sum of the link boundary threshold and the preset step size, reduce the power of the access point, wherein The above-mentioned link boundary threshold represents the threshold value at which the workstation is always in an environment with weak receiving power;

TPC information collection is periodic, and is controlled by the TPC information collection cycle timer. When the cycle arrives, the two timers (period timer and timeout timer) are reset to start a new round of collection process, in which TPC information collection The timeout timer is used to specify the duration of TPC information collection each time. After timeout, stop collecting TPC information and report the measurement report of the link boundary value; the preset step size needs to support 3dB step size, and can also optionally support 1dB or 2dB steps;

S132. If the link boundary values of some of the workstations have been updated in real time, or if there is a link boundary value not greater than the sum of the link boundary threshold and the preset step size, do not reduce the power of the access point ;

If the TPC information collection timeout timer expires, but there are still STAs in the link boundary value table that have not updated their link boundary values, it can be considered that the network status at this time is not good, or the communication quality between these STAs and the AP is poor , at this time, the original TPC information of these STAs is retained, and the "link boundary value table update status" is set to "partial update", and the power of the AP is not reduced.

When the AP does not interfere with other neighboring APs, the AP power is increased according to the maximum transmit power limit of the AP. In order to avoid excessive load after the AP power is increased, in one embodiment, the AP is increased in step S150. AP power can include:

If the current load of the AP is large, increase the load of the AP after avoiding power increase, so that the load of the AP is too large, then maintain the power of the AP, otherwise increase the power of the AP.

The present invention can also dynamically adjust the power of the corresponding AP through the acquisition of real-time vulnerability information and TPC information when there are blind spots in the network and poor communication quality of users, so as to make up for and improve the network blind spots and communication quality changes caused at this time. In the worst case, the reasons for the blind area include: AP failure, AP transmission power is too low, etc. For the situation of AP failure, as shown in Figure 2, the method provided by the present invention is:

S210. Obtain a neighbor access point of the failed access point;

AC (Access Controller, access controller) obtains the invalid AP through the heartbeat message mechanism, that is, uses CAPWAP (Control And Provisioning of Wireless Access Points Protocol Specification, controlled wireless access point and configuration) protocol for communication, and AC sends an inquiry periodically , the AP responds to indicate that the AP is working normally, and if the AP does not respond, it indicates that the AP is invalid; the neighbor AP of the failed AP can be obtained through the channel quality evaluation table, or obtained through other methods;

S220. Acquire a new access point that does not have the maximum transmission power from the access points in the neighboring cell;

S230. Raise the new access point to maximum transmission power;

Polling all neighboring APs of the failed AP, if the neighboring AP has reached the maximum transmit power, keep the power, otherwise, the neighboring AP will be forced to increase to the maximum transmit power, regardless of the load and interference of the AP when the power is forced to increase Condition.

If the STA communication quality is in a relatively poor state for a long time, it may be because the AP transmission power is too small at this time, there is a coverage blind area. For the situation that the AP transmission power is too small, as shown in Figure 3, the method provided by the present invention is:

S310. Periodically update the link boundary value of the station associated with the access point;

Periodically collect the TPC information of the AP, and update the link boundary value of the STA associated with the AP;

S320. If the number of times the link boundary value of the workstation is smaller than the link boundary threshold is greater than the preset number of times, mark the workstation as a failed workstation;

Poll all STAs associated with the AP, and record the number of times the link boundary value of each STA is less than the link boundary threshold. When the number of records is greater than the preset number, it means that the STA has been in an environment with low received power for a long time, or This STA may be in the coverage blind zone or at the edge of the blind zone, mark the STA as a failed STA, and prepare for judging whether to adjust the AP power;

S330. Determine whether the number of failed workstations among the workstations associated with the access point is greater than a preset number, if yes, and the load of the access point and the interference to other neighboring access points are not large, the access point If the maximum transmit power is not reached, enter step S340, otherwise enter step S350;

When the number of failed STAs is greater than the preset number, in order to avoid increasing the AP power to cause greater interference to neighboring APs or the AP’s load is too large, it is necessary to consider the AP’s load and interference before determining whether to increase the AP’s power. Power; the case where the AP has little interference with other neighboring APs includes moderate interference and no interference between the AP and the neighboring AP; if the AP is already at the maximum transmit power, keep the original power of the AP , at this time, the problem of coverage blind area can be solved by adding AP nodes there;

S340. Increase the power of the access point;

S350. No power adjustment is performed.

If the AP is in the overloaded state for a long time and no load balancing measures can be taken, the present invention also provides a method that can reduce the load of the overloaded AP. In one embodiment, if the load of the access point is too large, reduce the power of the access point, if the access point is the minimum transmission power, keep the power of the access point unchanged; when the overloaded AP is When the transmit power is minimum, a disassociation operation can be sent to some STAs to force them to leave the overloaded AP.

In order to avoid frequent power adjustments to the AP and reduce user experience, the present invention also provides a method for ensuring that the transmission power remains in a stable state for a certain period of time after a certain power adjustment. In one embodiment, before the step of reducing or increasing the power of the access point, the steps may further include:

Set the power maintenance timer, determine whether the power maintenance timer reaches the preset time, if so, reduce or increase the power of the access point, otherwise do not perform power adjustment, wherein the power maintenance timer is used to ensure that the power is within maintaining a stable state within the preset time;

After the step of reducing or increasing the power of the access point, the step may further include:

The power maintenance timer is reset, and timing is restarted.

After a power adjustment is performed, the power maintenance timer is started. If the power maintenance timer does not reach the preset time when the power adjustment command is issued, the power adjustment will not be responded to. The power maintenance timer can be set on the AC or the AP. If it is set on the AC, no control command will be sent to the AP. If it is set on the AP, it will not respond to the power adjustment command sent by the AC.

Based on the same inventive concept, the present invention also provides a power adjustment device for a wireless local area network. The specific implementation of the device of the present invention will be described in detail below with reference to the accompanying drawings.

As shown in Figure 4, a power adjustment device for a wireless local area network, comprising:

The interference degree acquisition module 100 is configured to obtain the interference situation of the access point by scanning channels of the access point, and evaluate the interference degree of the access point to other neighboring cell access points according to the interference situation, wherein the The interference levels mentioned above include relatively large interference, no interference, and moderate interference;

A link boundary value acquisition module 200, configured to acquire the link boundary value of the workstation associated with the access point, wherein the link boundary value is determined according to the power value received by the workstation minus the lowest acceptable power value;

The power adjustment module 300 is configured to reduce the power of the access point according to the link boundary value and the minimum transmission power limit of the access point when the access point interferes with other adjacent cell access points. The power of the access point; when the access point interferes moderately with other adjacent cell access points, the power of the access point is maintained.

When the access point does not interfere with other adjacent cell access points, there may be a problem that the access point transmits less power. In order to better improve the network quality, in one embodiment, the power adjustment module 300 is also used to When the access point has no interference with other adjacent cell access points, the power of the access point is increased according to the maximum transmit power limit of the access point.

When the interference of the AP to the neighboring AP is large, it is necessary to reduce the power of the AP according to the link boundary value and the minimum transmission power limit of the access point. In order to avoid reducing the AP power to cause coverage blindness, in one embodiment Among them, the power adjustment module 300 reducing the power of the access point includes:

If the link boundary value of each workstation has been updated in real time, and the link boundary value is greater than the sum of the link boundary threshold and the preset step size, then the power adjustment module 300 reduces the power of the access point. power, wherein the link boundary threshold represents the threshold value at which the workstation is always in an environment with weaker received power;

If the link boundary values of some of the workstations have been updated in real time, or if there is a link boundary value not greater than the sum of the link boundary threshold and the preset step size, the power adjustment module 300 does not reduce the connection The power of the entry point.

When the AP does not interfere with other neighboring APs, the AP power is increased according to the maximum transmit power limit of the AP. In order to avoid excessive load after the AP power is increased, in one embodiment, the power adjustment module 300 liters High power of the access point includes:

If the current load of the access point is relatively large, the power adjustment module 300 maintains the power of the access point, otherwise the power adjustment module 300 increases the power of the access point.

The present invention can also dynamically adjust the power of the corresponding AP through the acquisition of real-time vulnerability information and TPC information when there are blind spots in the network and poor communication quality of users, so as to make up for and improve the network blind spots and communication quality changes caused at this time. In the worst case, the reasons for the blind area include: AP failure, AP transmission power is too low, etc. For the case of AP failure, as shown in Figure 5, the device of the present invention may also include:

Neighboring cell access point acquisition module 400, configured to obtain a neighboring cell access point of an invalid access point;

A new access point acquisition module 500, configured to acquire a new access point that is not the maximum transmission power from the access points of the neighboring cell;

The power adjustment module 300 increases the transmission power of the new access point to the maximum.

If the communication quality of the STA is in a relatively poor state for a long time, it may be because the AP transmission power is too small at this time, and there is a coverage blind area. For the case where the AP transmission power is too small, as shown in Figure 6, the device of the present invention may also include:

A link boundary value updating module 600, configured to periodically update the link boundary value of the workstation associated with the access point;

A workstation marking module 700, configured to mark the workstation as a failed workstation when the number of times the link boundary value of the workstation is smaller than the link boundary threshold is greater than a preset number of times;

A comparing module 800, configured to compare the number of failed workstations among the workstations associated with the access point with a preset number, if the number of failed workstations is greater than the preset number, and the load of the access point and other If the interference of the access point in the neighboring cell is not large and the access point has not reached the maximum transmit power, the power adjustment module 300 increases the power of the access point, otherwise no power adjustment is performed.

In order to avoid frequent power adjustments to APs and reduce user experience, the device of the present invention may also include a timer module for setting a power maintenance timer to determine whether the power maintenance timer reaches a preset time, and if so, the The power adjustment module 300 reduces or increases the power of the access point, otherwise the power adjustment module 300 does not perform power adjustment, wherein the power maintenance timer is used to ensure that the power remains in a stable state within the preset time;

After the power adjustment module 300 lowers or raises the power of the access point, the timer module is further configured to reset the power maintenance timer and restart timing.

If the AP is in an overload state for a long time and cannot perform any load balancing measures, the power adjustment module 300 of the present invention is also used to reduce the power of the access point when the load of the access point is too large. The point is the minimum transmit power, and the power adjustment module 300 keeps the power of the access point constant.

Other technical features of the device of the present invention are the same as those of the method of the present invention, and will not be repeated here.

The above-mentioned embodiments only express several implementation modes of the present invention, and the description thereof is relatively specific and detailed, but should not be construed as limiting the patent scope of the present invention. It should be pointed out that those skilled in the art can make several modifications and improvements without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent for the present invention should be based on the appended claims.

Claims (10)

1. a power regulating method for WLAN (wireless local area network), is characterized in that, comprises step:

Obtain by access point scanning channel the disturbed condition that described access point is subject to, and assess the annoyance level of described access point to other adjacent area access point according to described disturbed condition, wherein said annoyance level comprises that interference is larger, noiseless, it is moderate to disturb;

Obtain the link boundary value of the work station of described access point association, the performance number that wherein said link boundary value receives according to described work station deducts the minimum performance number of accepting and determines;

If it is larger that described access point disturbs other adjacent area access point, according to the minimum emissive power restriction of described link boundary value and described access point, reduce the power of described access point;

If it is moderate that described access point disturbs other adjacent area access point, keep the power of described access point.

2. the power regulating method of WLAN (wireless local area network) according to claim 1, is characterized in that, also comprises step: if described access point is noiseless to other adjacent area access point, and according to the maximum transmit power limit of described access point, the power of the described access point that raises.

3. the power regulating method of WLAN (wireless local area network) according to claim 2, is characterized in that, the power that reduces described access point comprises:

If all real-time update of the link boundary value of each described work station, and described link boundary value be all greater than link boundary threshold and default step-length and, reduce the power of described access point, wherein said link boundary threshold represents that work station is in the threshold value in the weak environment of received power always;

If the link boundary value real-time update of the described work station of part, or exist link boundary value be not more than described link boundary threshold and described default step-length and, do not reduce the power of described access point;

The power of described access point of raising comprises:

If the present load of described access point is larger, keep the power of described access point, otherwise the power of the described access point that raises.

4. the power regulating method of WLAN (wireless local area network) according to claim 1, is characterized in that, also comprises step:

Obtain the adjacent area access point of inefficacy access point;

From the access point of described adjacent area, obtain the new access point that is not maximum transmission power;

Described new access point is increased to maximum transmission power;

And/or:

Cycle is the link boundary value of the work station of new access point association more;

If the link boundary value of work station is less than the number of times of described link boundary threshold and is greater than preset times, this work station is labeled as unsuccessfully to work station;

Whether the number that judges failed work station in the work station of described access point association is greater than preset number, if, and the load of described access point and little, the described access point of the interference of other adjacent area access point is not reached to maximum transmission power, the power of described access point that raises, otherwise do not carry out power adjustment.

5. according to the power regulating method of the WLAN (wireless local area network) described in claim 1 to 4 any one, it is characterized in that, also comprise step: if the load of access point is excessive, reduce the power of described access point, if described access point is minimum emissive power, keep the power of described access point constant;

Before the step of reduction or rising access point power, also comprise step:

Power is set and keeps timer, judge that described power keeps timer whether to arrive Preset Time, if so, reduces or the described access point power that raises, otherwise do not carry out power adjustment, wherein said power keeps timer to be used for guaranteeing that power keeps stable state in described Preset Time;

After the step of reduction or the described access point power that raises, also comprise step:

Keep timer to reset described power, restart timing.

6. a power adjustment apparatus for WLAN (wireless local area network), is characterized in that, comprising:

Annoyance level acquisition module, for obtaining by access point scanning channel the disturbed condition that described access point is subject to, and assess the annoyance level of described access point to other adjacent area access point according to described disturbed condition, wherein said annoyance level comprises that interference is larger, noiseless, it is moderate to disturb;

Link boundary value acquisition module, for obtaining the link boundary value of work station of described access point association, the performance number that wherein said link boundary value receives according to described work station deducts the minimum performance number of accepting and determines;

Power regulation module, in the time that described access point is larger to other adjacent area access point interference, according to the minimum emissive power restriction of described link boundary value and described access point, reduces the power of described access point; At described access point, other adjacent area access point is disturbed when moderate, keep the power of described access point.

7. the power adjustment apparatus of WLAN (wireless local area network) according to claim 6, it is characterized in that, described power regulation module is also in the time that described access point is noiseless to other adjacent area access point, according to the maximum transmit power limit of described access point, and the power of the described access point that raises.

8. the power adjustment apparatus of WLAN (wireless local area network) according to claim 7, is characterized in that, the power that described power regulation module reduces described access point comprises:

If all real-time update of the link boundary value of each described work station, and described link boundary value be all greater than link boundary threshold and default step-length and, described power regulation module reduces the power of described access point, and wherein said link boundary threshold represents that work station is in the threshold value in the weak environment of received power always;

If the link boundary value real-time update of the described work station of part, or exist link boundary value be not more than described link boundary threshold and described default step-length and, described power regulation module does not reduce the power of described access point;

The raise power of described access point of described power regulation module comprises:

If the present load of described access point is larger, described power regulation module keeps the power of described access point, the power of described access point otherwise described power regulation module raises.

9. the power adjustment apparatus of WLAN (wireless local area network) according to claim 6, is characterized in that, also comprises:

Adjacent area access point acquisition module, for obtaining the adjacent area access point of inefficacy access point;

New access point acquisition module, for obtaining the new access point that is not maximum transmission power from described adjacent area access point;

Described new access point is increased to maximum transmission power by described power regulation module;

And/or:

Link boundary value update module, for the more link boundary value of the work station of new access point association of cycle;

Work station mark module, while being greater than preset times, is labeled as unsuccessfully work station by this work station for be less than the number of times of described link boundary threshold at the link boundary value of work station;

Comparison module, for the number of the failed work station of work station and the size of preset number of more described access point association, if the number of failed work station is greater than described preset number, and the load of described access point and little, the described access point of the interference of other adjacent area access point is not reached to maximum transmission power, the described power regulation module power of described access point that raises, otherwise do not carry out power adjustment.

10. according to the power adjustment apparatus of the WLAN (wireless local area network) described in claim 6 to 9 any one, it is characterized in that, also comprise timer module, be used for arranging power and keep timer, judge described power keeps timer whether to arrive Preset Time, and if so, described power regulation module reduces or the described access point power that raises, otherwise described power regulation module is not carried out power adjustment, wherein said power keeps timer to be used for guaranteeing that power keeps stable state in described Preset Time;

After the power of described power regulation module reduction or the described access point that raises, timer module also, for keeping timer to reset described power, restarts timing;

Described power regulation module also, in the time that the load of access point is excessive, reduces the power of described access point, if described access point is minimum emissive power, described power regulation module keeps the power of described access point constant.