Method for automatically selecting the operating channel of a WIFI access point.

Abstract

The invention presents a method for automatically selecting the operating channel of a Wi-Fi access point belonging to a local area network of access points, comprising a channel selection initialization step consisting of scanning the available channels and selecting the least used channel, characterized in that the following are measured episodically: the power consumption of the electronic circuit of at least one of said access points; the number of users connected to said access point; and the bandwidth distributed by said at least one of said access points. Furthermore, the channel change of said access point is commanded when the result of a function exploiting the three aforementioned values ​​exceeds a threshold value and / or when the power level of at least one neighboring access point drops and / or when at least one neighboring access point changes its channel. (Single figure)

Description

Title of the invention: Method for automatically selecting the operating channel of a WIFI access point. Scope of the invention

[0001] The present invention relates to the field of wireless computer networks, in particular WIFI networks or radio bridges.

[0002] The proliferation of WiFi networks based on the IEEE 802.11 wireless RLAN (radio local area network) standard, commercially known as WiFi®, has led to the availability of multiple WiFi-equipped devices and inexpensive integrated circuits implementing various aspects of the IEEE 802.11 standards. This makes them attractive for the provision of "last mile" voice and data services from a fiber backbone to end users in sparsely populated rural areas, or generally in areas where existing alternatives for the provision of "last mile" services, such as WiMAX, terrestrial telephone line networks, cable TV-based solutions, and fiber optics, are too expensive or impractical for other reasons.

[0003] A great many connected devices now include a Wi-Fi connection (smartphones, computers, internet boxes, home automation devices, etc.), and Wi-Fi technology thus meets users' need to connect everywhere. Mobile traffic now represents more than 50% of internet traffic. There is an economic advantage: unlike 3G / 4G, the use of Wi-Fi frequencies is most often free for the user. Less expensive to create than a wired network, public Wi-Fi is increasingly appealing to local authorities and private operators, for example, campsite or holiday park operators, or business parks. Equipping a site facilitates access to online public services and audiovisual services, increases the visibility of local events, and strengthens the site's economic and tourist appeal.

[0004] However, the Wifi signal has a limited range of a few tens of meters and is sensitive to obstacles as well as interference.

[0005] Interference results from multiple causes which can occur unexpectedly, such as electromagnetic radiation from equipment brought near an access point or coming into operation, for example a baby monitor, a security camera, a microwave oven, another Wifi access point controlled by a third party, or even certain Bluetooth equipment which also uses the 2.4 GHz frequency used by Wifi, concurrently with the 5 GHz band.

[0006] The consequences of interference are the degradation of signal quality, the drastic reduction of throughput or even the loss of connection of equipment dependent on the disturbed access point.

[0007] In the event of a degradation in the quality of the Wi-Fi signal, the usual procedure is to change the channels of the access points controlled by the operator to select a less congested channel for each controlled access point. Of course, for an operator controlling several access points on the same network, changing the channel of one access point can cause new interference with another access point that was already using that channel, and the problem can thus propagate recursively. State of the art

[0008] Modifying the channels of a set of access points controlled by an operator is a tedious task, especially since interference can occur at any time, requiring constant monitoring and a very high level of responsiveness. It has, of course, been proposed to automate the detection of interference experienced by one or more access points on the same network.

[0009] By way of example, US patent 8923225 proposes a method for avoiding interference in a WiFi network comprising a plurality of WiFi terminals, consisting of:

[0010] a) use one or more of the WiFi terminals to collect radio interference information, wherein the radio interference information includes packet header information for WiFi packets received on a plurality of WiFi channels;

[0011] b) communicate radio interference information from one or more of the WiFi terminals to a network management system (NMS) for storage in a network radio environment database (NRED); and,

[0012] c) receive transmission and reception parameters sent by the NMS to one or more of the WiFi terminals for use of the latter in WiFi data communications by said one or more of the WiFi terminals in order to avoid or reduce radio interference in the WiFi network;

[0013] wherein a) includes the collection, by one or more of the WiFi terminals, of packet header information from WiFi packets received by said one or more WiFi terminals on the plurality of WiFi channels, and wherein b) includes the communication to the NMS of the packet header information which is collected by the WiFi terminal(s) from the WiFi packets received as part of the radio interference information.

[0014] This solution is not entirely satisfactory because it involves the use of unconventional Wi-Fi terminals adapted for collecting transmission and reception parameters. These specific terminals differ from conventional Wi-Fi terminals in at least two important aspects:

[0015] a) they include means for detecting interfering radio signals at a variety of RF frequencies within the network's operating frequency range to obtain Wi-Fi and other RF interference information at their respective locations, and

[0016] b) They use a new TDD / TDM (time-domain duplexing / time-domain multiplexing) mechanism to coordinate their transmission and reception in order to avoid interference between conventional terminals. These specific terminals include conventional PH Y-level hardware for processing communication packets, but employ a new transmission synchronization algorithm.

[0017] Patent EP2083594B1 proposes another method for reducing interference in a wireless communication system formed by a plurality of radio access networks (RAN1, RAN2, RAN3), each radio access network having a network manager (GW1, GW2, GW3) designed to communicate with a plurality of nodes (BS1, ...BS5; BS6, ...BS10; BS11, ...BS16) associated with the network manager, and each radio access network having a frequency spectrum divisible into a plurality of sub-channels used by the nodes for wireless communication, said frequency spectrum at least partially overlapping the frequency spectrum of one or more other radio access networks. This method comprises the following steps: • the network manager (GW1, GW2, GW3) of each radio access network (RAN1, RAN2, RAN3) executes a spectrum allocation process for the allocation of sub-channels to its nodes; • the nodes (BS1, ...BS5; BS6, ...BS10; BS11, ...BS16) of each radio access network (RAN1, RAN2, RAN3) perform wireless communication using the sub-channels allocated to them; • the network manager (e.g., GW1) of a radio access network (RANCI) estimates an expected level of internal interference within the radio access network during said wireless communication and receives, from its associated nodes (BS1, ...BS5), data indicating the actual levels of interference experienced by the nodes and affecting the sub-channels allocated to them, said interference occurring both internally within the radio access network (RAN1) and externally from other radio access networks (RAN2, RAN3); • The network manager (GW1) of said radio access network (RAN1) compares a sum of said actual interference levels with said interference level, determining whether said sum exceeds said level by at least a predetermined threshold to determine whether coordination with another network manager (GW2, GW3) is necessary to reduce externally occurring interference and, if so: • the network manager (GW1) of said radio access network (RAN1) notifies this requirement, along with a list of the affected sub-channels, to the network manager (GW2, GW3) of at least one of the other radio access networks (RAN2, RAN3); and • The network manager (GW2, GW3) creates another radio access network (RAN2, RAN3) and again runs the spectrum assignment process on its associated nodes (BS6, ...BS10; BS11, ...BS16) according to said list of assigned subchannels to reduce the level of interference experienced by the nodes (BS1, ...BS5) via the radio access network (RAN1).

[0018] This solution also requires direct information on the level of interference.

[0019] Japanese patent JP5189160B2 proposes a method for suppressing common frequency interference in a wireless communication system.This method applies to a system comprising a main control module and at least two cellular base stations in which the main control module interacts with each cellular base station with respect to interference suppression information and obtains the interference terminal information in each cell; the main control module collects the interference terminal information in each cell, determines the interference suppression programming method and sends the interference terminal information and the interference suppression programming method to the corresponding cellular base station; each cellular base station performs the programming according to the interference suppression programming method sent by the main control module in combination with the programming requirement in the local cell.The present invention makes it possible to effectively avoid common frequency interference between cells, to improve user reception performance at the cell edge, to increase cell coverage, and to improve system throughput and spectrum efficiency.

[0020] US patent 20140226572A1 relates to a wireless access point (AP) that stores a region code identifying a country / region where said wireless AP is intended to operate. This region code may be provided by the vendor of the wireless AP or in response to information communicated either by the user of the wireless AP or via a GPS receiver. In response to the area code, the wireless access point (AP) identifies one or more Wi-Fi channels in the area that are subject to interference due to non-Wi-Fi wireless communication channels approved for use in the area. The wireless access point then selects a Wi-Fi channel for wireless communication, avoiding the Wi-Fi channels identified as being subject to interference in the area.

[0021] This solution is based on machine learning and has the drawback of being a static solution that does not take into account fluctuations in usage. The channel is selected from a database, but does not provide solutions for the unexpected appearance of disruptive equipment.

[0022] US patent 8914055 proposes a network node configured to select resources for a direct communication link between a first wireless device and a second wireless device in a cellular communication network, comprising: a transceiver subsystem configured to enable wireless communication; and

[0023] a processing subsystem configured for: • select a downlink resource from the cellular communication network as the resource for the direct device-to-device communication link between the first wireless device and the second wireless device if a base station serving the first wireless device and a base station serving the second wireless device are equipped with an interference cancellation receiver and both the radio distance between the first wireless device and the base station serving the first wireless device and the radio distance between the second wireless device and the base station serving the second wireless device are less than a predefined threshold radio distance; and • Select an uplink resource from the cellular communication network as the resource for the direct device-to-device communication link between the first wireless device and the second wireless device if the base station serving the first wireless device and the base station serving the second wireless device are equipped with an interference cancellation receiver and at least one of the following: the radio distance between the first wireless device and the base station serving the first wireless device and the radio distance between the second wireless device and the base station serving the second wireless device is greater than the predefined radio distance threshold value; uses a "client" as a proxy to avoid connecting in case of interference; requires access to another client. Disadvantages of prior art

[0024] These solutions are not entirely satisfactory because they require the use of specific equipment for network administration. Solution provided by the invention

[0025] To remedy this drawback, the invention, in its most general sense, relates to a method for automatically selecting the operating channel of a Wi-Fi access point belonging to a local area network of access points, comprising a channel selection initialization step consisting of scanning the available channels and selecting the least used channel, characterized in that the following are measured episodically: a. The power consumption of the electronic circuit of at least one of said access points b. The number of users connected to said access point c. The bandwidth distributed by at least one of said access points

[0026] And we command the change of channel of said access point when the result of a function exploiting the three above-mentioned values ​​exceeds a threshold value and / or the power decrease of at least one neighboring access point and / or the change of channel of at least one neighboring access point.

[0027] Advantageously, a scan of the transmission channels of each of said neighboring access points is also ordered to control the channel change of said access point when the result of a function exploiting the three above-mentioned values ​​exceeds a threshold value and / or the power decrease of at least one neighboring access point and / or the channel change of at least one neighboring access point.

[0028] Preferably, said initialization step consists of ordering a scan of the transmission channels of neighboring access points to select the new channel of one of said access points.

[0029] According to one variant, the reduction of the transmission power of said access point is also ordered when the result of a function exploiting the three above-mentioned values ​​exceeds a threshold value [to reduce the number of connected users].

[0030] Preferably, the consumption (POE), bandwidth and number of users (ARP table) values ​​are measured at the switch to which the WIFI access point is connected.

[0031] According to a particular embodiment, an alert signal is triggered when the result of a function exploiting the three aforementioned values ​​exceeds a threshold value. Detailed description

[0032] [Fig.1] Fig.1 represents the schematic topology of a local network of WIFI access points, comprising three access points (1, 2, 3) connected to a switch (10) by wired links (11, 12, 13).

[0033] The switch (10) has known probes for each port, allowing data to be retrieved via an SSH, TELNET, or CLI type connection, with lines of code specific to the switch manufacturer (10), from a server (20) connected to the switch (10).

[0034] This server (20) connects to the switch (10) and initially commands the local network initialization step. This initialization consists, for example, of assigning a Ci channel to the first access point (1), randomly or from a predefined database, or of an environmental scan of third-party access points, not controlled by the switch (10) and broadcasting a wifi signal on the same area covered by the controlled local network.

[0035] The other access points (2, 3) are configured by the server (20) by a choice of channel C; so as to reduce interference between the access points (1 to 3).

[0036] The invention then consists of episodically collecting on the server (20) data measured on the switch (10).

[0037] This data includes, for each of the access points (1 to 3): a. The power consumption of the electronic circuit of at least one of said access points b. The number of users connected to said access point c. The bandwidth distributed by at least one of said access points

[0038] This data is acquired by the server (20) by the episodic sending of command lines allowing the data to be retrieved via the intelligent platform management interface (IPMI) of the access point circuit, via a Java applet for example.

[0039] In the event of the appearance of a source of interference (4), in the [Fig.1] in the coverage area of ​​the access point (3), the electrical consumption measured on the switch (10) on the port corresponding to the access point (3) will increase and this variation will be detected by the server (20), which will command a change of channel C; for each of the terminals (1 to 3).

[0040] For the access point (3) disturbed by an interference source (4), the new channel will be chosen to be the furthest from the original channel corresponding to the disturbance channel.

[0041] The Ci channels of neighboring access points (1,2) will also be modified if they present a risk of interference between access points (1 to 3).

[0042] The server (20) can also command an increase in the transmission power of one or more access points to increase the signal-to-noise ratio in the channel of the interference source (4).

[0043] The server (20) can also command the reduction of the transmission power of the access point (3) using the same channel as the source of interference (4) in order to reduce the number of connected devices and force them to distribute themselves across neighboring access points (1, 2). In this case, the server (20) will command the increase of the transmission power of the neighboring access points (1, 2) within the limits of the maximum permitted power levels.

[0044] By way of example, the server (20) determines a variable T corresponding to the interference rate, according to the following formula:

[0045] T = L*(P / B)- K*(P / N)

[0046] Where • P denotes the electrical power consumed by an access point (1 to 3) measured on the switch (10) • N denotes the number of devices connected to an access point (here 3) • B denotes the bandwidth consumed by an access point (1 to 3) measured on the switch (10)

[0047] K and L are coefficients that depend on the installed equipment and the WIFI technology.

[0048] To determine the coefficient L, tests are carried out consisting of intentionally generating known interference with a pulse generator, and measuring the impact on the power consumption of a relevant access point.

[0049] To determine the coefficient L, a large number of connected devices are connected to one of the access points (1 to 3) in an interference-free environment, and the impact on consumption of the number of connected client devices is measured. This second coefficient is optional.

[0050] This variable T of an access point (1) is episodically compared to a threshold value, or the previous value, or even the value T for neighboring access points (2, 3) to conditionally trigger the Q channel reconfiguration processing.

Claims

Demands

1. A method for automatically selecting the operating channel of at least one WIFI access point belonging to a local access point network, comprising a channel selection initialization step consisting of scanning the available channels and selecting the least used channel, characterized in that the following are measured episodically: a. The power consumption of the electronic circuit of at least one of said access points b. The number of users connected to said access point c. The bandwidth distributed by said at least one of said access points And that the channel change of said access point is commanded when the result of a function exploiting the three above-mentioned values ​​exceeds a threshold value.

2. Method for automatically selecting the operating channel of a WIFI access point according to claim 1 characterized in that a scan of the transmission channels of each of said neighboring access points is further commanded to command the channel change of said access point when the result of a function exploiting the three above-mentioned values ​​exceeds a threshold value and / or the power decrease of at least one neighboring access point and / or the channel change of at least one neighboring access point.

3. Method for automatically selecting the operating channel of a WIFI access point according to claim 1 characterized in that said initialization step consists of ordering a scan of the transmission channels of neighboring access points to select the new channel of one of said access points.

4. Method for automatically selecting the operating channel of a WIFI access point according to claim 1 characterized in that it also controls the reduction of the transmission power of said access point when the result of a function exploiting the three values ​​mentioned above exceeds a threshold value to reduce the number of connected users.

5. A method for automatically selecting the operating channel of a WIFI access point according to claim 1, characterized in that An alert signal is triggered when the result of a function exploiting the three aforementioned values ​​exceeds a threshold value.

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