KR100711183B1 - Method of the channel assignment of wireless lan in 2.4ghz band - Google Patents

Abstract

The present invention relates to a method for setting an access point channel of a 2.4 GHz wireless LAN, wherein radio interference is prevented when a channel in which a channel used between APs of a wireless LAN is at least four channels longer than the channel currently being used and in use. The present invention provides a method and apparatus for automatically designating an AP channel of a new WLAN based on the fact that it does not occur, and automatically analyzes beacon signals of neighboring APs when performing AP channel setting of a WLAN in a specific space. By doing so, an optimal channel selection is possible.

WLAN, Access Point, AP, Channel Setup

Description

How to set access point channel of 2.4GHz wireless LAN {METHOD OF THE CHANNEL ASSIGNMENT OF WIRELESS LAN IN 2.4GHZ BAND}

1 is a configuration diagram of an access point channel setting apparatus of a wireless LAN to which the present invention is applied;

2A to 2C are flowcharts illustrating a method for establishing an access point channel of a WLAN according to the present invention.

<Description of Symbols for Major Parts of Drawings>

10 antenna 20 radio frequency chip

30: baseband chip 40: MAC chip

50: automatic channel setting program

The present invention relates to a WLAN channel setting method, and more particularly, to an access point (AP) channel setting method of a new 2.4 GHz WLAN.

In general, a wireless LAN uses a center frequency of 2.400 GHz to 2.4835 GHz to transmit digital data at high speed. In the 2.4 GHz AP, 13 channels are designated at intervals of 5 MHz in the 2.400 GHz to 2.4835 GHz band. Conventionally, the AP channels of the new WLAN do not consider the utilization channels of the neighboring APs. As shown in Fig. 1, a center frequency corresponding to one channel number was randomly or randomly selected from 13 channels.

However, such a conventional AP channel setting method has a disadvantage in that the transmission speed of the AP is lowered or the communication connection is disconnected when there is at least one AP using neighboring adjacent channels. That is, by assigning the same channel to a new AP or to an adjacent channel that may cause radio interference, there is a problem of lowering a transmission speed of the WLAN or disconnection of a communication connection.

Accordingly, the present invention has been made to solve the above-mentioned problems of the prior art, and an object of the present invention is to use the channel between the AP of the WLAN and the channel in use and at least four or more channels. The present invention provides a method for setting an access point channel of a 2.4 GHz WLAN that can automatically designate an AP channel of a new WLAN based on the fact that it does not cause radio interference.

In the 2.4 GHz wireless LAN access point channel setting method of the present invention for achieving the above object, when the AP of the wireless LAN is installed, a new 2.4 GHz wireless to analyze the surrounding radio environment to select the optimal channel Applicable to the method of setting an AP channel of a LAN, the method comprising: searching for a beacon signal of a neighboring AP and selecting channel numbers CH_S having a reception power of -75 dBm or more; And a second step of setting each AP channel according to the number NS of the channel numbers CH_S selected in the first step.

Hereinafter, an access point channel setting method of a 2.4 GHz WLAN of the present invention will be described in detail with reference to the accompanying drawings.

1 is a configuration diagram of an AP channel setting apparatus of a 2.4GHz wireless LAN to which the present invention is applied, and includes an antenna 10, a radio frequency chip 20, a baseband chip 30, and a medium access control (MAC). : Medium Access Control) chip 40, automatic channel setting program 50 mounted on the MAC chip 40, and the like. Among them, the automatic channel setting program 50 includes an automatic channel setting algorithm for selecting an optimal channel by analyzing the surrounding radio wave environment when an AP of a 2.4 GHz WLAN is installed.

2A to 2C are flowcharts illustrating an AP channel setting method of a 2.4 GHz wireless LAN according to the present invention, and present an automatic channel setting algorithm performed by the automatic channel setting program. Here, symbols used in FIGS. 2A to 2C are defined as follows.

AP: access point;

NS: number of channel numbers with power received at AP greater than -75 dBm;

CH_AP: channel number set in the AP;

CH_S: channel number with power received at AP greater than -75 dBm;

X1: channel number;

X2: channel number;

X_min: the smallest number of channel numbers for which power received at the AP is greater than -75 dBm;

X_max: the largest number of channel numbers for which the power received at the AP is -75 dBm or more;

CH_P_max: Channel number with the largest power received by the AP;

Set_CH_S: a set of channel numbers consisting of [1, 5, 9], [1, 5, 13], [1, 9, 13], [5, 9, 13];

X_L: The smallest number of values excluding X_min among channel numbers whose power received at the AP is -75 dBm or more;

X_U: The largest number among the values excluding X_max among the channel numbers with the power received at AP greater than -75dBm.

First, when setting a channel in the AP of the WLAN, the automatic channel setting program 50 selects the channel number (CH_S) of the power received at the AP is more than -75dBm (100).

① When NS = 0

If there is no number NS of the channel number CH_S selected in step 100 (NS = 0) (110), the number 13 is designated as the channel number of the AP (120) and ends (130). Go to step 140.

② When NS = 1

If the number NS of the channel number CH_S selected in step 100 is one (NS = 1) (140), the channel number X1 (X1 = 13-CH_S) and the channel number X2 (X2 = CH_S-1) are obtained. 150 and 160, the channel numbers X1 and X2 are compared (170), otherwise, the process moves to the next step 200.

In step 140, when the channel number X1 is greater than the channel number X2 by comparing the channel numbers X1 and X2, a value obtained by adding 4 to the selected channel number CH_S is designated as the channel number CH_AP = CH_S + 4. After 180 ends (130). In addition, when the channel number X1 is smaller than the channel number X2 by comparing the channel numbers X1 and X2, a value obtained by subtracting 4 from the selected channel number CH_S is designated as the channel number (CH_AP = CH_S-4) of the AP (190). End (130).

③ When NS = 2

If the number NS of the channel numbers CH_S selected in step 100 is two (NS = 2) (200), the minimum channel number (X_min) and the maximum channel number (X_max) are calculated (205). Go to next step 280.

In step 200, a predetermined calculation process is performed using the minimum channel number X_min and the maximum channel number X_max calculated in step 205.

If minus 1 minus 1 is greater than or equal to 4 (X_min-1> = 4) (210), minus 4 minus minus 4 is the channel number of the AP (CH_AP = X_min- 4) and then (220) ends (130), and if the value obtained by subtracting the maximum channel number (X_max) from 13 is greater than or equal to 4 (13-X_max> = 4) (230), the maximum channel number (X_max) After adding 4 to the channel number of the AP (CH_AP = X_max + 4) (240) and ending (130), the maximum channel number (X_max) minus the minimum channel number (X_min) divided by 2 If greater than or equal to 4 ((X_max -X_min) / 2> = 4) (250), the minimum channel number (X_min) plus 4 is designated as the channel number of the AP (CH_AP = X_min + 4) (260). End (130).

If the steps 210, 230, and 250 do not correspond, the channel number CH_P_max of the maximum reception power is designated as the channel number of the AP (270), and then ends (130).

④ when NS = 3

If the number NS of the channel numbers CH_S selected in step 100 is three (NS = 3) (280), the three selected channel numbers are [1, 5, 9], [ 1, 5, 13], [1, 9, 13], and [5, 9, 13] determine whether it belongs to Set_CH_S which is a set of channel numbers (290), otherwise, go to the next step 410.

In step 290, if the selected three channel numbers belong to Set_CH_S, the selected three channel numbers are sorted in large order, and then subtracted one-to-one with channel numbers 1, 5, 9, 13, and the rest is not zero. A value is designated as the channel number of the AP (CH_AP = [1 5 9 13]-Set_CH_S) (300) and ends (310).

In step 290, if the selected three channel numbers do not belong to Set_CH_S, the minimum channel number (X_min), the maximum channel number (X_max), and the smallest value among the values except X_min among the channel numbers with power received at the AP greater than -75 dBm The number X_L and the largest number X_U of values excluding X_max among channel numbers whose power received at the AP is greater than -75 dBm are calculated (315), using the calculated X_min, X_max, X_L and X_U. A predetermined calculation process is performed.

If the value of X_min minus 1 is greater than or equal to 4 (X_min-1> = 4) (320), the value after adding 4 to X_min is designated as the channel number of the AP (CH_AP = X_min + 4) (330). (310).

In addition, if the value obtained by subtracting X_max from 13 is greater than or equal to 4 (13-X_max> = 4) (330), after assigning X_max plus 4 as the channel number of the AP (CH_AP = X_max + 4) (350) End (310).

In addition, if the value obtained by subtracting 2 from X_max minus X_U is greater than or equal to 4 ((X_max-X_U) / 2> = 4) (360), subtracting 4 from X_max subtracts 4 from the AP's channel number (CH_AP = X_max). 4) and ends (370) (310).

In addition, if the value of 2 divided by X_L minus X_min is greater than or equal to 4 ((X_L-X_min) / 2> = 4) (380), the value of the AP plus 4 is added to the channel number of the AP (CH_AP = X_min). + 4) and then ends (390).

If it is not the steps 320 to 380, the channel number CH_P_max of the maximum reception power is designated as the channel number (CH_AP = CH_P_max) of the AP (400) and ends (310).

⑤ When NS> = 4

As illustrated in FIG. 2C, the case in which the number NS of the channel numbers CH_S selected in step 100 is four or more (NS> = 4) is as follows.

First, it is determined whether the number NS of the selected channel number CH_S is four (410). When the number NS of the selected channel number CH_S is four (NS = 4), all four measured values are determined. It is checked whether CH_S is all channel numbers 1, 5, 9, and 13 (420). When all four measured CH_S are channel numbers 1, 5, 9, and 13, the channel number CH_P_max of the maximum reception power is designated as the channel number CH_AP = CH_P_max of the AP (430), and then ends (440). .

If the selected channel number (CH_S) is not composed of 1, 5, 9, 13 or the number (NS) of the selected channel number (CH_S) is four or more (NS> 4), the minimum channel number (X_min), The maximum channel number (X_max), the smallest number (X_L) of the values except X_min among the channel numbers with the power received at the AP greater than -75 dBm, and the values except the X_max among the channel numbers with the power received at the AP greater than -75 dBm. The largest number X_U is calculated (445), and a predetermined calculation process is performed using the calculated X_min, X_max, X_L, and X_U.

If the value of X_min minus 1 is greater than or equal to 4 (X_min-1> = 4) (450), specify X_min plus 4 as the channel number (CH_AP = X_min + 4) of the AP (460). (440).

If 13 minus X_max is greater than or equal to 4 (13-X_max> = 4) (470), specify X_max plus 4 as the channel number (CH_AP = X_max + 4) of the AP (480). (440).

If X_max minus X_u is equal to or greater than 4 ((X_max-X_u) / 2> = 4) (490), subtract 4 from X_max to subtract 4 from AP (CH_AP = X_max-4 (500) and ends (440).

If X_L minus X_min divided by 2 is greater than or equal to 4 ((X_L-X_min) / 2> = 4) (510), X_min plus 4 is added to the channel number of the AP (CH_AP = X_min + 4) and then 520 ends (440).

If X_U minus X_L divided by 2 is greater than or equal to 4 ((X_U-X_L) / 2> = 4) (530), subtract 4 from X_U to subtract channel 4 (CH_AP = X_U-4). ) And ends (540).

If it does not correspond to the steps 450 to 530, the channel number CH_P_max of the maximum reception power is designated as the channel number (CH_AP = CH_P_max) of the AP (550) and ends (440).

As described above, in the method of setting an access point channel of a 2.4 GHz WLAN according to the present invention, when a channel is assigned to a new AP of a 2.4 GHz WLAN, channel numbers searched by automatically demodulating the beacon signal of the neighboring AP are detected. Based on this, it is effective to set an optimal channel setting for a new AP.

Claims (11)

delete delete delete A first step of searching for a beacon signal of an access point of a new WLAN through an automatic channel setting algorithm performed by an automatic channel setting program, and determining the number of channel numbers CH_S whose received power is equal to or greater than a setting value; And a second step of setting an access point channel corresponding to the number of channel numbers, When the number of the channel number (NS) is not present, the access point channel setting method of the new 2.4GHz wireless LAN, characterized in that designation 13 as the channel number of the access point. The method of claim 4, wherein when the number NS of the channel numbers is one, Obtaining channel number X1 and channel number X2 by a predetermined operation; Comparing the sizes of the channel numbers X1 and X2; If the channel number X1 is greater than the channel number X2, the selected channel number plus 4 is designated as the channel number of the access point. If the channel number X1 is less than the channel number X2, the value minus 4 is selected from the selected channel number. To specify the channel number of the access point Method of setting an access point channel of a new 2.4GHz WLAN, characterized in that to proceed. (Where X1 = 13-CH_S, X2 = CH_S-1) The method of claim 4, wherein when the number NS of the channel numbers is two, Obtaining the minimum channel number (X_min), which is the smallest number among the channel numbers whose power received at the access point is greater than or equal to the set value, and the maximum channel number (X_max), which is the largest number among the channel numbers whose power is received at the access point or greater than the set value, step; If minus 1 minus 1 is greater than or equal to 4 (X_min-1> = 4), specify minus 4 minus as the access point channel number. If the maximum channel number minus 13 is greater than or equal to 4 (13-X_max> = 4), the maximum channel number plus 4 is designated as the access point channel number. If the value obtained by subtracting 2 from the maximum channel number minus the minimum channel number is greater than or equal to 4 ((X_max -X_min) / 2> = 4), specify the minimum channel number plus 4 as the access point channel number. step Method of setting an access point channel of a new 2.4GHz WLAN, characterized in that to proceed. The method of claim 4, wherein when the number NS of the channel numbers is three, Determining whether three channel numbers belong to a set (Set_CH_S) of channel numbers consisting of [1, 5, 9], [1, 5, 13], [1, 9, 13], and [5, 9, 13] step; If the selected three channel numbers belong to the set Set_CH_S, the selected three channel numbers are sorted in large order, and then subtracted one-to-one with channel numbers 1, 5, 9, and 13, and then accesses the other non-zero value. The channel number of the point, If the three selected channel numbers do not belong to the set Set_CH_S, the minimum channel number X_min, the maximum channel number X_max, and the values other than the minimum channel number among the channel numbers of which the power received at the access point is greater than or equal to a set value are included. Designating a channel through a predetermined operation by obtaining the smallest number (X_L) and the largest number (X_U) among the channel numbers whose power received at the access point is greater than or equal to the set value except the maximum channel number. Method of setting an access point channel of a new 2.4GHz WLAN, characterized in that to proceed. The method of claim 7, wherein the channel designation by the operation, If the value obtained by subtracting 1 from the minimum channel number is greater than or equal to 4 (X_min-1> = 4), a value obtained by adding 4 to the minimum channel number is designated as the channel number of the access point. If the value of 13 minus the maximum channel number is greater than or equal to 4 (13-X_max> = 4), specify the maximum channel number plus 4 as the access point channel number. If the power received by the access point from the maximum channel number is greater than or equal to the set value, the value obtained by dividing 2 by the largest number among all channel numbers except the maximum channel number is greater than or equal to 4 ((X_max-X_U) / 2 > = 4) Specify the channel number of the access point by subtracting 4 from the maximum channel number. If the power received by the access point is greater than or equal to 4 divided by 2 from the smallest number minus the minimum channel number among the channel numbers above the set value ((X_L-X_min) / 2 > = 4) A method of setting an access point channel for a new 2.4 GHz WLAN, characterized in that the minimum channel number plus 4 is designated as the access point channel number. The method of claim 4, wherein the number NS of the channel numbers is four or more. Determining whether all the measured channel numbers are 1, 5, 9, 13; If all the measured channel numbers are 1, 5, 9, 13, the channel number CH_P_max of the maximum reception power is designated as the channel number of the access point, If the measured channel number is not composed of 1, 5, 9, 13 or the number of the channel number is 4 or more (NS> 4), the minimum channel number (X_min), the maximum channel number (X_max), the access point The smallest number (X_L) among the channel numbers whose power received is greater than or equal to the set value (X_L) and the largest number among the channel numbers whose power received by the access point is greater than or equal to the set value except the maximum channel number. Specifying a channel through a predetermined operation by obtaining (X_U) Method of setting an access point channel of a new 2.4GHz WLAN, characterized in that to proceed. 10. The method of claim 9, wherein the channel designation by the operation, If minus 1 minus 1 is greater than or equal to 4 (X_min-1> = 4), specify the min. Channel number plus 4 as the access point channel number. If the value of 13 minus the maximum channel number is greater than or equal to 4 (13-X_max> = 4), specify the maximum channel number plus 4 as the access point channel number. If the power received by the access point from the maximum channel number is greater than or equal to the set value, the value obtained by dividing 2 by the largest number among the channel numbers except the maximum channel number is greater than or equal to 4 ((X_max-X_u) / 2 > = 4) Specify the maximum channel number minus 4 as the access point channel number. If the power received by the access point is greater than or equal to 4 divided by the minimum channel number minus the minimum channel number among the channel numbers above the set value, the value is greater than or equal to 4 ((X_L-X_min) / 2> = 4) Specify the minimum channel number plus 4 as the access point channel number. The highest number among the channel numbers of which the power received at the access point is greater than or equal to the set value, except for the maximum channel number, is the smallest value except the minimum channel number among the channel numbers whose power is greater than or equal to the set value. If the value of 2 divided by 2 is greater than or equal to 4 ((X_U-X_L) / 2> = 4), the highest number among the channel numbers except the maximum channel number among the channel numbers whose power received at the access point is greater than or equal to the set value A method of setting an access point channel of a new 2.4 GHz WLAN, wherein the value obtained by subtracting 4 is designated as the channel number of the access point. 11. The method according to any one of claims 6, 8, and 10, wherein the channel number CH_P_max of the maximum reception power is used as the channel number of the access point when it does not correspond to the operation of the step of specifying the channel number. An access point channel setting method of a new 2.4GHz wireless LAN, characterized in that the designation.

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