Communication method, method for putting an access point into standby mode, access point, beacon frame and corresponding computer programs

Abstract

Communication method, Method for putting an access point into standby mode, access point, beacon frame and corresponding computer programs. The invention relates to a communication method implemented by an access point of a telecommunications network in a standby state, the communication method comprising: waking up an analog part of a radio signal processing chain intended to be transmitted by the access point; broadcasting, by the analog part of the processing chain, at least one beacon frame including at least one parameter indicating that the access point is in a standby state; putting the analog part of the processing chain into standby mode. Figure for the abstract: Fig. 1.

Description

Title of the invention: Communication method, Method for putting an access point into standby mode, access point, beacon frame and corresponding computer programs. Technical field

[0001] The invention belongs to the general field of telecommunications.

[0002] It is more particularly relevant in the context of wireless access networks conforming to the IEEE (“Institute of Electrical and Electronics Engineers”) 802.11 family of standards or Wi-Fi networks (for “Wireless Fidelity”).

[0003] The invention relates more specifically to mechanisms for putting into standby mode and managing the standby state of an access point to such a Wi-Fi network. Previous technique

[0004] In a global context, where environmental concerns and economic imperatives converge, the rationalization of energy consumption has become a central pillar of policies and initiatives aimed at promoting sustainable and balanced development.

[0005] Industrialists, in particular, are increasingly aware of the importance of energy savings as a means of preserving the environment and promoting sustainable and virtuous economic growth. As such, and for many years now, reducing energy consumption has been central to the deployment of the various generations of wireless access networks compliant with the IEEE 802.11 family of standards, or Wi-Fi networks.

[0006] Indeed, with Wi-Fi networks being massively deployed throughout the world, whether in private homes, businesses or many public places, they constitute a prime target for achieving energy savings.

[0007] As such, many solutions aimed at reducing the energy consumption of Wi-Fi networks have been developed or are under development.

[0008] A first example of such a solution consists of allowing a user device, or STA station, on this Wi-Fi network to enter a standby state, or, depending on the circumstances, to shut down for pre-negotiated periods of time with the access point (AP) to which the STA is connected. During the STA's standby period, the AP stores in memory the data packets destined for the STA that it receives. The STA, for its part, is required to wake up from its standby state at regular intervals in order to intercept messages sent by the AP informing it of the possible availability of pending data packets. This The STA standby mechanism is known by the acronym PSM for "Power Save Mode".

[0009] To support the deployment of APs and multi-antenna STAs, mechanisms enabling the shutdown or standby mode of all or part of the radio signal processing chains intended for transmission by an STA have been developed in order to reduce the latter's energy consumption without sacrificing its connectivity. An example of such a solution is the SMPS mechanism for "Spatial Multiplexing Power Save".

[0010] The latest energy consumption management solutions involve multi-link devices or MLDs (Multi-Link Devices). A multi-link STA, or AP, can aggregate several radio links to treat them as a single link by exposing a single MAC (Medium Access Control) address.

[0011] Although some STAs or APs are MLD equipment, for cost reasons they only have a single radio signal processing chain. Since they can only have one active link at a time, these STAs, known as MLSRs for "Multi-Link Single Radio," switch from one radio link to another according to their transmission schedule.

[0012] To facilitate this switching between the different radio links while reducing the STA's energy consumption, an eMLSR (enhanced Multi-Link Single Radio) mechanism was developed. This eMLSR mechanism probes a secondary radio link to detect a possible transmission of a special frame. If such a special frame is detected, it means that the STA must switch its next transmissions to this secondary link.

[0013] Since the vast majority of STAs are user devices such as smartphones, tablets, personal computers, or sensors like temperature or motion sensors, they are generally equipped with batteries. For this reason, many proposed solutions for reducing the energy consumption of Wi-Fi networks primarily target STAs.

[0014] In order to go even further in this approach to reducing the energy consumption of Wi-Fi networks, it is interesting to take into account other equipment composing these Wi-Fi networks such as APs.

[0015] There is therefore a need for new solutions for managing and / or reducing energy consumption that can be applied to APs. Description of the invention

[0016] To this end, and according to a first aspect, the invention relates to a communication method implemented by an access point of a telecommunications network in a standby state, the communication method comprising: a. a wake-up of an analog part of a radio signal processing chain intended to be transmitted by the access point; b. a broadcast, by the analog part of the processing chain, of at least one beacon frame including at least one parameter indicating that the access point is in a standby state; c. a standby state of the analog part of the processing chain.

[0017] Correspondingly, the invention relates to a beacon frame intended to be broadcast by an access point of a telecommunications network, the beacon frame comprising at least one parameter indicating that the access point is in a standby state.

[0018] In conjunction, the invention relates to a method for processing a beacon frame implemented by a station located in a geographically served area, called the coverage area, by a first access point of a telecommunications network in a standby state, the method comprising: - the reception of at least one beacon frame broadcast by the first access point, including at least one parameter indicating that the first access point is in a standby state, - the processing of the tag frame.

[0019] The invention is based on the concept of a phantom access point, or AP. A phantom AP is an AP whose presence can be detected by stations, or STAs, located within a geographic area served by that AP, or AP coverage area, even though it is in standby mode, thanks to the transmission, via the analog portion of its processing chain, of specific beacon frames, known as phantom frames. Because this AP is in standby mode, the STAs located within its coverage area, although informed of its presence, cannot attach to it.

[0020] In the remainder of this document, the standby state of the AP refers to a condition in which the AP operates with reduced capacity. When in standby mode, many of the AP's hardware components are shut down, i.e., they cease to function. This is the case, for example, for the digital and analog parts of the beacon frame processing chain, the memories, some of the communication interfaces, etc.

[0021] Similarly, the execution of certain software components of the AP can be stopped. This could be, for example, the upper part of the Media Access Control (MAC) layer, also known as the upper MAC layer. The MAC layer is an important part of the wireless communication protocol stack. In particular, it is responsible for managing communication between the The MAC layer is generally divided into two main components: the upper MAC layer and the lower MAC layer. It manages the various equipment in a telecommunications network and ensures fair and efficient use of the shared wireless medium.

[0022] More specifically, the upper MAC layer provides functions such as network management, security, and quality of service (QoS) functions. It also implements protocols such as 802.11 for security and 802.11 for QoS. Finally, the upper MAC layer communicates with higher-level protocol layers, such as the network and transport layers, to provide the necessary network management, security, and QoS functionalities.

[0023] In such a case, the data stored in the AP's RAM is, for example, copied to non-volatile memory in order to preserve the state of the software, such as the operating system, that was running at the time of entering sleep mode.

[0024] When in standby mode, an AP must nevertheless remain available to respond to specific events such as, for example, receiving a wake-up signal. To this end, certain components of the AP, such as those enabling it to receive messages from the telecommunications network, are not placed in standby mode. Such a standby state of the AP is considered "full" as opposed to a "partial" standby state during which the analog part of the processing chain is woken up to proceed with the transmission of the phantom beacon frames according to the invention.

[0025] By indicating its presence via the emission of phantom beacon frames, the AP allows these STAs either to wait until its effective awakening (i.e. until it exits the sleep state) or to decide to attach to another AP if possible.

[0026] Indeed, the processing of the beacon frame by the station, in a particular implementation of the processing method, comprises: - the determination, from information contained in the beacon frame, of a duration remaining until the access point exits the standby state.

[0027] More specifically, when the time remaining until the access point exits sleep mode exceeds a threshold, the station, in a particular implementation of the processing method, proceeds to: - the identification of at least one other active access point within its coverage area, - establishing a connection with the other access point.

[0028] Conversely, when the time remaining until the access point exits standby mode is less than or equal to the threshold, the station proceeds to: - establishing a connection with the first access point upon expiry of the remaining time until the first access point exits sleep mode.

[0029] Thus, an STA intercepting such a phantom beacon frame determines that it is located in the coverage area of ​​an AP of a Wi-Fi network but that any attempt to attach to the Wi-Fi network via this AP is doomed to failure until this AP comes out of its standby state (whether partial or complete).

[0030] As is known, a beacon frame is a message broadcast periodically by the AP, for example every 100 ms (milliseconds), to announce the availability of a Wi-Fi network. In addition to information about the AP itself, this message also includes information about the Wi-Fi network that allows STAs located within the coverage area to have the necessary information to, if appropriate, connect to this Wi-Fi network via the AP.

[0031] More specifically, a typical beacon frame includes, among other things, a Wi-Fi network SSID (Service Set Identifier), information about the supported protocols, for example 802.lin, 802.11be, etc., the data transmission rate (upstream, i.e., from the STA to the AP, and / or downstream, i.e., from the AP to the STA), or the frequency bands used, for example 2.4 GHz or 5 GHz (GigaHertz), etc. The beacon frame may also include information about the security protocols used to communicate with the STAs, such as WEP for Wired Equivalent Privacy, WPA for Wi-Fi Protected Access, or WPA2 for Wi-Fi Protected Access 2, etc.

[0032] However, such a beacon frame in the prior art is not configured to carry information relating to an AP standby state.

[0033] The present invention advantageously proposes to exploit such a beacon frame to carry new information indicating that the AP is in a standby state, thus generating a phantom beacon frame. The invention can, for this purpose, utilize existing fields not used in conventional beacon frames.

[0034] Advantageously, such a modification of the classic standardized beacon frames allows their reuse in the context of the present invention, avoiding the creation of a new type of message.

[0035] It is of course also possible to create new fields, in addition to the existing fields, intended to carry the information that the AP sending the phantom beacon frame is in standby mode.

[0036] Like any radio signal transmitting equipment, the AP includes at least one radio signal processing chain for the signals it is intended to transmit.

[0037] Typically, such a radio processing chain comprises: - a digital component that encompasses all the processing applied to the digital signals transmitted to the AP for their transmission by the AP, such as encoding and modulation, and - an analog part which covers the processing applied to the signals which have been processed by the digital part of the radio processing chain in preparation for their transmission by the AP antennas.

[0038] More specifically, the digital part of the AP radio processing chain includes, in particular but not exclusively, error correction or FEC for "Forward Error Correction", the processing of digital signals according to a given multiplexing scheme, e.g. the OFDM multiplexing scheme for "Orthogonal Frequency-Division Multiplexing", then the modulation of the signals obtained according to a given modulation scheme, e.g. a QAM modulation for "Quadrature Amplitude Modulation", etc.

[0039] Once all the desired digital processing has been applied to the signals to be transmitted, these digital signals are converted into analog signals by means of a digital-to-analog converter. The analog signals thus obtained are then processed by the analog part of the radio processing chain.

[0040] The analog part of the radio processing chain includes analog circuits such as mixers, oscillators, filters, amplifiers and one or more antennas intended to transmit the processed analog signals.

[0041] In the present solution, the phantom beacon frame to be broadcast is in a format ready to be processed by the analog part of the AP's radio transmission chain. This means, for example, that error correction, a multiplexing scheme, and a modulation scheme have already been applied to the phantom beacon frame during the implementation of the communication method that is the subject of the invention. It is then possible to activate only the analog part of the radio processing chain in order to broadcast the phantom beacon frame.

[0042] More specifically, the analog part of the radio processing chain comes out of the standby state during step a) and the appropriate analog processing is applied to the phantom beacon frame, the last step of these analog processing being the transmission of the processed analog signal carrying the information contained in the phantom beacon frame by the AP antenna(s) during step b). During the execution of these steps a) and b), the AP is in a partial standby state.

[0043] Once the ghost beacon frame has been broadcast, step c) of returning to a standby state is implemented. The execution of step c) can also be triggered by the reception of a command message from a telecommunications network device.

[0044] By only using (and waking up) the analog part of the AP's radio transmission chain for the broadcast of the ghost beacon frame, the present solution makes it possible to reduce the energy consumption of the AP.

[0045] In particular modes of implementation of the communication process, the beacon frame is processed by a digital part of the processing chain prior to the access point being put into standby mode.

[0046] Storing such a pre-processed ghost beacon frame by the digital part of the radio transmission chain while the AP is active (i.e., before it switches to a standby state) contributes to reducing the AP's energy consumption. Indeed, since the ghost beacon frame has been processed by the digital part of the radio transmission chain prior to the AP entering standby mode, there is no need to wake the AP up to allow the ghost beacon frame to be broadcast.

[0047] In particular modes of implementation of the communication process, the sequence of steps a) to c) is implemented according to a dissemination schedule.

[0048] Such a schedule, which can be stored with the phantom beacon frame prior to the AP being put into standby mode, includes the various dates and / or times at which the phantom beacon frame is intended to be broadcast. Thus, the phantom beacon frame may not be broadcast at regular time intervals.

[0049] In particular embodiments, the sequence of steps a) to c) is implemented periodically.

[0050] By broadcasting the ghost beacon frame at regular time intervals, better interoperability of the present solution with the current fleet of STAs is enabled.

[0051] In particular modes of implementation of the communication process, the sequence of steps a) to c) is implemented upon receipt of a command issued by an entity of the telecommunications network.

[0052] Receiving this command wakes up the analog part of the radio transmission chain and triggers the broadcast of the ghost beacon frame. This allows the analog part of the radio transmission chain to be completely switched off, and it then does not need to monitor the time remaining until its next wake-up phase. Such a command is, for example, received by a communication module configured to implement a) to c).

[0053] In particular modes of implementation of the communication process, the beacon frame further includes a parameter relating to an exit from the programmed standby state of the access point.

[0054] In order to allow the STAs located within the AP's coverage area to decide whether it is more advantageous for them to wait for the AP to exit standby mode or to attempting to attach to another AP, the ghost beacon includes in one of its fields information indicating the time remaining until the AP exits sleep mode.

[0055] In such a case, the parameter relating to exiting the programmed sleep state of the access point may, in particular, belong to the group comprising: - a date for exiting standby mode for the access point; - a number of beacon frames remaining to be broadcast until the exit from the state of access point monitoring; - a countdown leading to the access point exiting sleep mode.

[0056] In particular modes of implementation of the communication process, the beacon frame further includes at least one connection parameter intended to be filled by stations seeking to attach themselves to said access point.

[0057] This parameter excludes STAs that are unable to interpret the new information contained in the phantom beacon frame and that treat it as a standard beacon frame. In this way, these STAs do not make numerous futile attempts to connect to the Wi-Fi network via the AP. This advantageously allows the present solution to be implemented without the generation of STAs attempting to attach to the AP.

[0058] Indeed, in a particular implementation of the processing method, the processing of the beacon frame by the station includes the determination, from information contained in the beacon frame, of a connection parameter intended to be filled by the station.

[0059] More specifically, when the station does not meet the connection parameter, the processing method includes, in a particular implementation: - the identification of at least one second active access point within its coverage area, - establishing a connection with the second access point.

[0060] According to a second aspect, the invention relates to a method for putting a telecommunications network access point into standby mode, the standby mode method comprising: - obtaining at least one beacon frame including at least one parameter indicating that the access point is in a standby state; - memorization of the tag frame; - putting the access point into standby mode.

[0061] This method of putting an access point into standby mode offers the same advantages mentioned above as the communication method according to the invention. It can typically be implemented before triggering the implementation of a communication method according to the invention.

[0062] In specific implementation modes of putting an access point into standby mode, obtaining the beacon frame includes: - generation of the tag frame; - processing of the beacon frame by a digital part of a radio signal processing chain intended to be emitted by the access point.

[0063] In particular modes of implementation of the method of putting an access point into standby mode, this includes receiving the beacon frame emitted by an entity of the telecommunications network.

[0064] In particular modes of implementation of the method of putting an access point into standby mode, the putting of the access point into standby mode is triggered by the memorization of the beacon frame.

[0065] Generating the ghost beacon frame prior to entering standby mode ensures that the radio processing chain is little or not used to transmit data to the STAs.

[0066] Thus, the digital part of the radio processing chain is available to process the ghost beacon frame. Once all the digital processing applied to the ghost beacon frame has been completed and the frame has been stored, the AP enters standby mode.

[0067] In particular modes of implementation of the method of putting an access point into standby mode, the putting of the access point into standby mode is triggered according to a standby schedule.

[0068] Such a calendar, which can be stored with the ghost beacon frame prior to the AP being put into standby mode, includes the different dates and / or times at which the AP enters standby mode.

[0069] In particular modes of implementation of the method of putting an access point into standby mode, the access point exits standby mode according to a schedule for exiting standby mode.

[0070] Such a calendar, which can be stored with the phantom beacon frame prior to the AP entering standby mode, includes the various dates and / or times at which the AP wakes up from standby mode. This wake-up calendar may correspond to the broadcast calendar of the phantom beacon frame or may constitute a separate calendar.

[0071] In particular modes of implementation of the method of putting an access point into standby mode, the access point exits standby mode following the receipt of a command issued by an entity of the telecommunications network.

[0072] In particular, in one specific embodiment, it can be envisaged that only the reception of this command from equipment belonging to the telecommunications network has the capacity to fully wake up the AP. As such For example, such a command can be received by a communication interface between the access point and the telecommunications network, such as an Ethernet port. This command can be of the Wake-on-WAN (Wide Area Network) type or the Wake-on-LAN (Local Area Network) type. A Wake-on-WAN or Wake-on-LAN command allows a device on a remote telecommunications network to be woken from sleep mode.

[0073] For example, this command may consist of an Ethernet frame, commonly called a "magic packet", containing the byte sequence "FF FF FF FF FF FF" followed by sixteen repetitions of the MAC address of the equipment to be woken up / shut down, possibly accompanied by a password.

[0074] In particular embodiments, the method of putting an access point into standby mode includes deleting the processed beacon frame when the access point exits standby mode.

[0075] Thus, there is no risk that a phantom beacon frame will be mistakenly broadcast by the AP suggesting that the AP is in standby mode when it is active.

[0076] Correspondingly, the invention also relates to an access point of a telecommunications network comprising: - a beacon frame acquisition module configured to obtain at least one beacon frame including at least one parameter indicating that the access point is in a standby state; - a memory module configured to memorize the tag frame; - a sleep mode module configured to put the access point into sleep mode; - a communication module configured for: • wake up an analog part of a radio signal processing chain intended to be emitted by the access point; • distribute the processed tag frame; and • put the analog part of the processing chain into standby mode.

[0077] This access point has the same advantages mentioned above as the communication method and the method for putting the AP into standby mode according to the invention.

[0078] The invention also relates to a station located in a geographical area served by an access point of a telecommunications network in a standby state, the station comprising: - a receiving module configured to receive at least one beacon frame broadcast by the access point including at least one parameter indicating that the access point is in a standby state; - a processing module configured to process the tag frame.

[0079] The invention also relates to a computer program on a recording medium, this program being capable of being implemented in a computer or more generally in an AP according to the invention and comprising instructions adapted to the implementation of a communication method as described above.

[0080] The invention also relates to a computer program on a recording medium, this program being capable of being implemented in a computer or more generally in an AP according to the invention and comprising instructions adapted to the implementation of a sleep state method as described above.

[0081] Each of these programs can use any programming language, and be in the form of source code, object code, or code intermediate between source code and object code, such as in a partially compiled form, or in any other desirable form.

[0082] The invention also relates to an information medium or a recording medium readable by a computer, and comprising instructions for a computer program as mentioned above.

[0083] The information or recording medium can be any entity or device capable of storing programs. For example, the medium can include a storage means, such as a ROM, for example a CD-ROM or a microelectronic circuit ROM, or a magnetic recording means, for example a hard disk drive, or a flash memory.

[0084] On the other hand, the information or recording medium can be a transmissible medium such as an electrical or optical signal, which can be transmitted via an electrical or optical cable, by radio link, by wireless optical link or by other means.

[0085] The programs according to the invention can in particular be downloaded onto an Internet-type network.

[0086] Alternatively, the information or recording medium may be an integrated circuit in which a program is incorporated, the circuit being adapted to execute or to be used in the execution of the processes according to the invention.

[0087] It can also be envisaged, in other embodiments, that the processes according to the invention and the AP according to the invention have in combination all or part of the aforementioned characteristics. Brief description of the drawings

[0088] Other features and advantages of the present invention will become apparent from the description below, with reference to the accompanying drawings, which illustrate an example of an embodiment without being limiting in any way. In the figures:

[0089] [Fig.1] [Fig.1] represents a communication system in a telecommunications network, according to the invention, in a particular embodiment;

[0090] [Fig.2] [Fig.2] schematically represents the hardware architecture of a computer on which the AP according to the invention is based, belonging to the communication system of the [Fig.1];

[0091] [Fig.3] [Fig.3] represents, in flowchart form, the main steps of a method for putting an AP into standby mode according to the invention, as implemented by an AP conforming to the invention belonging to the communication system of [Fig.1];

[0092] [Fig.4] [Fig.4] represents an example of a simplified structure of a tag frame phantom conforming to the invention

[0093] [Fig.5] [Fig.5] represents, in flowchart form, the main steps of a communication method according to the invention, as implemented by an AP according to the invention belonging to the communication system of [Fig.1]

[0094] [Fig. 6] [Fig. 6] represents, in flowchart form, the main steps of a beacon frame processing method according to the invention, as implemented by an STA belonging to the communication system of [Fig. 1]. Description of the invention

[0095] Fig. 1 represents a communication system 1, according to the invention in a particular embodiment.

[0096] In this embodiment, system 1 comprises: - at least one AP 2 access point of an NW telecommunications network, conforming to the invention, and including in particular a CSTR chain for processing radio signals intended to be emitted by the AP 2; - at least one user device or STA 3 station capable of interpreting the ghost beacon frames conforming to the invention, and - at least one user equipment or STA 4 station, known as STA Legacy, which is not capable of interpreting the ghost beacon frames conforming to the invention.

[0097] In the remainder of the description and in [Fig.1], for the sake of simplification, only two STAs located in the geographical area served by AP 2 are considered. Of course, a higher number of STAs can be considered.

[0098] In the example in [Fig. 1], AP 2 is an AP as defined by any one of the standards in the IEEE 802.11 family of standards (with the adaptations necessary for the implementation of the invention, described below). When active, AP 2 regularly transmits the classic beacon frames mentioned above to indicate to STAs 3 and 4 its presence and the possibility for them to attach to the NW network.

[0099] Such classic beacon frames are defined, for example, in section 10.3.3.2 of document 802.11-1997 entitled "Standard for Wireless LAN Medium Access Control (MAC) and Physical Payer (PHY) specifications" published on November 18, 1997.

[0100] In this context and in the embodiment described herein, the STA 3 is a station as defined by any one of the standards in the IEEE 802.11 family of standards (with the adaptations necessary for the implementation of the invention, described below). It is assumed here that the STA 3 is capable of interpreting all the information contained in the phantom beacon frames broadcast by the AP 2 in accordance with the invention.

[0101] The Legacy 4 STA is also a station as defined by the IEEE 802.11 family of standards. However, it is assumed here that this Legacy 4 STA is not capable of interpreting certain information contained in the phantom beacon frames broadcast by the AP 2 in accordance with the invention. This could be, for example, stations conforming to the 802.11be standard or to standards belonging to the 802.11 family prior to the 802.11be standard. These aspects are also discussed in more detail with reference to [Fig. 6].

[0102] The processing applied to the ghost beacon frames by STAs 3 and 4 is described in more detail with reference to [Fig.6].

[0103] In the embodiment described herein, the AP 2, the STA 3, and the STA Legacy 4 have the hardware architecture of a computer 5 as illustrated in [Fig. 2]. This hardware architecture includes, in particular, a PROC processor, a RAM MEM, a ROM, a non-volatile NVM, and COM communication means enabling, in particular, the AP 2 to communicate with the STA 3 and / or the STA Legacy 4 and with one or more devices (not shown in the figures) belonging to the NW network. The NVM constitutes a storage medium according to the invention, readable by the PROC processor, on which one or more program(s) according to the invention are stored.

[0104] A first program, denoted PROG1 when the hardware architecture of computer 5 is that of AP 2, is stored in the non-volatile NVM memory and includes instructions defining the main steps of a communication method according to the invention as implemented by AP 2. It more specifically defines the functional module of AP 2, which relies on and / or controls all or part of the PROC, MEM, ROM, NVM, and COM elements of computer 5 mentioned above.

[0105] In the embodiment described here, this first program PROG1 defines in particular the following functional module of the AP 2 (represented in [Fig.1]), which is activated to broadcast phantom frames when the AP 2 is in a partial standby state: - a 2A communication module configured for: • wake up an analog Panalog part of the CTSR chain for processing radio signals intended to be emitted by the AP 2; • broadcast a ghost beacon frame conforming to the invention; and • put the analog Panalog part of the CTSR processing chain into standby mode.

[0106] As mentioned earlier in this document, the AP 2 includes at least one CTSR radio signal processing chain which it is intended to emit.

[0107] Typically, such a CTSR processing chain comprises: - a digital part Pnum which covers all processing such as encoding and modulation, applied to the digital signals transmitted to AP 2 from one or more devices of the NW network for their transmission by AP 2, and - an analog Panalog part which covers the processing applied to the signals which have been processed by the digital part Pnum of the CTSR radio processing chain in order to be transmitted by the antenna(s) of AP 2. This analog Panalog part of the CTSR radio processing chain is, for example, controlled by the communication module 2A.

[0108] A second program, denoted PROG2 when the hardware architecture of computer 5 is that of AP 2, is stored in the non-volatile NVM memory and includes instructions defining the main steps of a sleep state method according to the invention as implemented by AP 2. It more specifically defines the functional modules of AP 2, which rely on and / or control all or part of the PROC, MEM, ROM, NVM, and COM elements of computer 5 mentioned above.

[0109] In the embodiment described here, this second program PROG2 defines in particular the following functional modules of the AP 2 (represented in [Fig. 1]), which are activated to put the AP 2 into standby mode: - a 2B phantom beacon frame acquisition module configured to obtain at least one phantom beacon frame including at least one parameter indicating that AP 2 is in a standby state; - a 2C memorization module configured to memorize the ghost beacon frame; - a 2D standby mode module configured to put the AP 2 into standby mode.

[0110] A third program, denoted PROG3 when the hardware architecture of computer 5 is that of the STA 3 or STA 4 Legacy, is stored in the NVM non-volatile memory and includes instructions defining the main steps of a method for processing a ghost beacon frame according to the invention as implemented by the STA 3 or by the STA 4 Legacy. It more specifically defines the functional modules of the STAs, which rely on and / or control all or part of the PROC, MEM, ROM, NVM, and COM elements of the computer 5 mentioned above.

[0111] In the embodiment described here, this third program PROG3 defines in particular the following functional module of the STA 3 and STA 4 Legacy (represented in [Fig.1]), which are activated to process ghost frames when the AP 2 is in a partial standby state: - a 3A receiving module configured to receive at least one ghost beacon frame broadcast by the access point including at least one parameter indicating that the access point is in a standby state; - a 3B processing module configured to process the ghost beacon frame. It should be noted that the 3B processing module differs in the processing it applies to the received ghost beacon frame, depending on whether it is a module from an STA 3 or a module from an STA 4 Legacy.

[0112] The operation of modules 3A and 3B is detailed further later with reference to the steps of the ghost beacon frame processing method according to the invention.

[0113] In the remainder of this document, the standby state of AP 2 refers to a condition in which AP 2 operates with reduced capacity. When in standby mode, many of the AP's hardware components are shut down, i.e., they cease to function. This is the case, for example, for the digital Pnum section and the analog Panalog section of the CTSR processing chain, as well as the ROM, NVM, etc. components.

[0114] Similarly, the execution of certain software components of the AP 2 can be stopped.

[0115] When in standby mode, AP 2 remains available to respond to specific events such as, for example, receiving a wake-up signal. To this end, certain components of AP 2, such as the PROC, MEM, and COM elements that enable it to receive messages from the NW telecommunications network, are not placed in standby mode.

[0116] In the remainder of this document, the standby state described above will be referred to as the "full" standby state of the AP 2 as opposed to the "partial" standby state during which the analog Panalog part of the CTSR processing chain is woken up to proceed with the broadcasting of the ghost beacon frames.

[0117] The operation of the AP 2 modules 2A to 2D is detailed further later with reference to the steps of the communication and standby processes according to the invention.

[0118] Figure 3 describes the main steps of the AP 2 standby method according to the invention, in a particular embodiment in which it is implemented by the AP 2.

[0119] In step E000, AP 2, which is in the active state, enters standby mode. When in the active state, AP 2 behaves normally: it broadcasts a beacon frame at regular intervals (e.g., every 100 ms) indicating the availability of a Wi-Fi network to which STA 3 and STA Legacy 4 can connect by attaching to AP 2. AP 2 can also exchange data with these two STAs when they are connected to the Wi-Fi network through it.

[0120] In a known manner, a beacon frame includes information about the Wi-Fi network itself which enables STAs located in the coverage area of ​​AP 2 to have the necessary information to, if necessary, attach to the Wi-Fi network.

[0121] More specifically, a classic beacon frame includes, among other things, a Wi-Fi network SSID identifier, information relating to the supported protocols, the data transmission rate, and the frequency bands used, for example, 2.4 GHz or 5 GHz, etc. Such a "classic" beacon frame broadcast by AP 2 can be interpreted by STA 3 and by STA Legacy 4.

[0122] In a first example, the AP 2 can be automatically brought into standby mode according to a given standby schedule, stored in the AP 2's non-volatile NVM memory.

[0123] In a second example, the AP 2 can be put into standby mode by receiving a command from equipment on the NW network (for example, a Wi-Fi controller that supervises several APs, an AP 2 management tool, etc.).

[0124] Finally, the AP 2 can be put into standby mode by receiving a command from an NW network device according to a standby schedule. It should be noted that the AP 2 can also be put into standby mode by the occurrence of other events.

[0125] In a first implementation of the standby mode method according to the invention, AP 2 receives (E010), from equipment belonging to the NW network, a message comprising a Ghost-Fr beacon frame intended to be broadcast by AP 2 when the latter is in standby mode. This step E010 is implemented, for example, by AP 2's acquisition module 2B.

[0126] A Ghost-Fr phantom beacon frame according to the invention differs from a classic beacon frame as defined in the prior art and mentioned above in that it carries information relating to a standby state of the AP 2.

[0127] More specifically, in the embodiment described here, a Ghost-Fr beacon frame is a beacon frame in which certain existing, unused fields are used to carry information indicating that the AP 2 is in a standby state. This information relating to the standby state of the AP 2 can also be included, in an alternative embodiment, in one or more new fields of a beacon frame created specifically for this purpose.

[0128] Fig. 4 represents an example of a simplified structure of a Ghost-Fr ghost beacon frame according to the invention.

[0129] Such a Ghost-Fr beacon frame comprises a MAC header and a frame body. The MAC header includes several fields, including, among other things, information related to the destination of the Ghost-Fr beacon frame, the cipher suite used for data encryption, and the data rate.

[0130] The Frame Body comprises a first group of fields called mandatory or "Mandatory" and at least a second group of fields called optional or "Optional". Every beacon frame, and by extension, every Ghost-Fr beacon frame, includes at least all the Mandatory fields in its frame body.

[0131] The Mandatory fields consist of: - a "Timestamp" field relating to the timestamp, it includes for example a reference time information intended to be used by STAs connected to the Wi-Fi network to synchronize with the NW network; - a "Beacon Interval" field indicating the duration of the time interval separating the broadcast of two consecutive beacon frames, e.g. 100 ms; - a "Capability" field containing information relating to the capacity of the NW network; and - an SSID field containing the Wi-Fi network identifier.

[0132] As is known, the "Capability" field is defined to carry information about the NW telecommunications network, such as the network type, for example, ESS for "Extended Service Set," in the case where AP 2 belongs to a set of APs sharing the same SSID. The "Capability" field can also carry information about the type of preamble of the beacon frame, e.g., "Short Preamble," or indicate the presence, in the beacon frame, of other fields such as a field carrying quality of service or QoS information, etc. Such a "Capability" field is defined in section 8.4.1.4 of document 802.11-2012 entitled "Standard for Information technology—Telecommunications and information exchange between Systems Local and metropolitan area networks—Specify requirements Part 11: Wireless LAN Medium Access Control (MAC) and Physical Payer (PHY) Specifications", published on March 29, 2012.

[0133] In the embodiment described herein, the present solution proposes, more specifically, to use one of the fields in the optional field group to store information relating to the sleep state of AP 2. Thus, in [Fig. 4], a Flag parameter is stored in one of the optional fields of the frame body of the Ghost-Fr phantom beacon frame. The presence of this Flag parameter in one of the optional fields of the body of the Ghost-Fr phantom beacon frame means that AP 2, which originated the broadcast of this Ghost-Fr phantom beacon frame, is in a sleep state.

[0134] In other embodiments, when the Flag parameter has a value of 1, it means that AP 2, which originated the broadcast of this Ghost-Fr phantom beacon frame, is in standby mode. Correspondingly, when the Flag parameter has a value of 0, it means that AP 2, which originated the broadcast, is active and that the frames it broadcasts are classic beacon frames and no longer Ghost-Fr phantom frames.

[0135] By way of example, the Flag parameter may be included in the optional "Time Advertisement element" field defined in the 802.11-2012 document entitled "Standard for Information technology--Telecommunications and information exchange between Systems Local and metropolitan area networks—Specify requirements Part 11: Wireless LAN Medium Access Control (MAC) and Physical Loyer (PHY) Specifications", published on March 29, 2012.

[0136] In variant embodiments of the invention, the Ghost-Fr ghost beacon frame further includes, in other optional fields of the frame body, at least one parameter relating to an exit from the programmed sleep state of the AP 2.

[0137] Such a parameter relating to an exit from the programmed standby state of AP 2 may be: - a date for exiting the AP 2 standby state; - a number of Ghost-Fr phantom frames remaining to be broadcast until AP 2 exits standby state; - a countdown leading to the AP 2 exiting sleep mode.

[0138] Such a list is given by way of example and is not intended to be exhaustive or limiting. It should be noted that the AP 2 may use one or more of these pieces of information relating to the AP 2 exiting its scheduled sleep mode. In the following description, and for the sake of simplicity, the information relating to the AP 2 exiting its scheduled sleep mode used by the AP 2 is the AP 2 exit date.

[0139] In other embodiments which can be combined with the previously described embodiments, the Ghost-Fr phantom beacon frame further includes at least one connection parameter intended to be filled by ST As seeking to attach to AP 2.

[0140] This connection parameter allows STA Legacy 4 to be excluded, which is not capable of interpreting the Flag parameter included in the Ghost-Fr phantom beacon frame and which treats the latter as a classic beacon frame.

[0141] Such a connection parameter may, for example, take the following form. The mandatory field "Capability" includes subfields among which the subfield "IBSS" (for Independent Basic Service Set) and the subfield "Short Slot Time".

[0142] The subfield "IBSS" is used, in a manner known per se, to indicate that communication takes place in an "ad hoc" type network, that is, a wireless network in which each STA communicates directly with the other STAs without going through an AP acting as a router. When the communication between STAs is "ad hoc" type communication, the subfield "IBSS" has a value of 1.

[0143] The "Short Slot Time" subfield, for its part, includes a parameter that relates to the duration of the minimum time interval separating the transmission of two consecutive frames. In Wi-Fi networks, when the "Short Slot Time" subfield has a value of 1, this means that the time interval separating the transmission of two consecutive frames is short, generally less than 10 microseconds, compared to 20 microseconds when the "Short Slot Time" subfield has a value of 0.

[0144] Simultaneously encoding the value of these two subfields to 1 leads to an inconsistency at the level of Legacy STAs, such as Legacy STA 4, which are then unable to process such a tag frame.

[0145] Such inconsistency is due to differences in configuration and operation between "ad hoc" networks and Wi-Fi networks capable of operating with short time intervals between the transmission of two consecutive frames.

[0146] More particularly, in an "ad hoc" network where each STA communicates directly with the other STAs, without going through an AP, it is advantageous to use a long time interval separating the transmission of two consecutive frames so that the STAs can adapt to possible interference and varied transmission conditions, as "ad hoc" networks do not benefit from the synchronization and centralized management offered by an AP.

[0147] Thus, in a classic way, the two subfields "IBSS" and "Short Slot Time" do not take the value 1 at the same time because these values ​​imply incompatible operating modes.

[0148] Faced with this inconsistency, the Legacy STAs do not seek to multiply attempts to connect to the Wi-Fi network via AP 2.

[0149] STAs capable of implementing the invention, such as STA 3, meanwhile, in the embodiment described here, know how to interpret these beacon frames in which the subfields "IBSS" and "Short Slot Time" both have the value 1 for what they are, namely Ghost-Fr phantom frames broadcast by an AP 2 in a standby state.

[0150] In such a scenario, given that the STAs capable of implementing the invention can interpret beacon frames in which the subfields "IBSS" and "Short Slot Time" both have a value of 1 as being Ghost-Fr frames, it is possible, in certain embodiments, to omit the Flag parameter to indicate that a beacon frame is a Ghost-Fr beacon frame and not a standard beacon frame. Thus, in these particular embodiments, the fact that the subfields "IBSS" and "Short Slot Time" both have a value of 1 constitutes at least one parameter indicating that the AP is in a standby state within the meaning of the invention.

[0151] The Ghost-Fr phantom beacon frame received during step E010 can be received together with the command received from equipment on the NW network triggering the AP 2 to standby.

[0152] In this first implementation of the AP 2 standby method, the Ghost-Fr ghost beacon frame received at step E010 is in a format ready to be processed by the analog Panalog part of the CTSR radio transmission chain of AP 2.

[0153] This means, for example, that error correction, a multiplexing scheme and a modulation scheme have been applied to the Ghost-Fr phantom beacon frame prior to its transmission to AP 2.

[0154] Upon receipt of this Ghost-Fr phantom beacon frame, the latter is memorized (E030), for example in memory module 2C of AP 2.

[0155] When the Ghost-Fr beacon frame has been stored, AP 2 enters (E040) a standby state. To do this, AP 2 puts all of its modules 2A to 2D into standby or turns off, as well as the ROM, NVM, Pnum digital section, and Panalog analog section of the CTSR processing chain. Since module 2D is configured to put AP 2 into standby, it will put modules 2A to 2C into standby or turn off, as well as the ROM, NVM, Pnum digital section, and Panalog analog section of the CTSR processing chain, before putting itself into standby.

[0156] In a second implementation of the standby mode method according to the invention, following step (E000), AP 2 generates a Ghost-Fr beacon frame (E020). For this, the acquisition module 2B fills the various fields of the Ghost-Fr ghost beacon frame with the appropriate information.

[0157] Once the Ghost-Fr ghost beacon frame is generated by the acquisition module The 2B ghost frame from AP 2 is processed by the digital part Pnum of the AP 2 CTSR radio signal processing chain (E021). As mentioned above, this processing includes, for example, error correction, the application of a multiplexing scheme such as OFDM, and the application of a modulation scheme such as QAM modulation. Of course, other multiplexing and modulation schemes can be applied when processing the Ghost-Fr ghost beacon frame.

[0158] Once all the processing of the digital part Pnum of the CTSR radio signal processing chain has been applied to the Ghost-Fr phantom beacon frame, the latter is stored (E030), for example in the storage module 2C of the AP 2.

[0159] Once the Ghost-Fr beacon frame is memorized, the AP 2 enters (E040) a standby state. To do this, the AP 2 puts all of its modules 2A to 2D into standby or switches them off, as well as the ROM, NVM, Pnum digital section and Panalog analog section of the CTSR processing chain.

[0160] In embodiments common to the first and second implementations, the standby state (E040) of AP 2 is triggered by the memorization of the Ghost-Fr phantom beacon frame.

[0161] The standby mode method of the invention also includes a step of exiting standby mode of the AP 2 (E050).

[0162] Thus, in a first example, the AP 2 can be automatically triggered to exit sleep mode according to a given wake-up schedule stored in the AP 2's NVM non-volatile memory. This wake-up schedule can be provided to the AP 2 at the same time as the sleep-entry schedule.

[0163] In a second example, the AP 2 can be woken from sleep mode by receiving a command from a device on the NW network. Such a command is, for example, a Wake on LAN command as described earlier in this document.

[0164] According to yet another example, the AP 2 can be triggered to wake up from sleep mode by receiving a Wake on LAN command according to a wake-up schedule. It should be noted that the AP 2 can also be triggered to wake up from sleep by the occurrence of other events.

[0165] It should be noted that exiting sleep mode can, in certain circumstances, trigger the deletion (E060) of the stored Ghost-Fr phantom beacon frame in the AP 2's 2C memory module. This limits the risk of such a Ghost-Fr phantom beacon frame being inadvertently transmitted while AP 2 is active.

[0166] Figure 5 describes the main steps of the communication method according to the invention, in a particular embodiment in which it is implemented by the AP 2.

[0167] It should be noted that this communication method is implemented only when the AP 2 is in standby mode. More specifically, this method is implemented following the execution of step E040 of the standby mode procedure described with reference to [Fig. 3]. The execution of the communication method according to the invention ends when step E050 of the wake-up mode procedure is implemented.

[0168] As discussed previously, when the AP 2 is in a standby state, its various modules 2A to 2D are also in a standby state or are switched off.

[0169] In order to indicate its presence and inform the STAs located within its coverage area that it is in a standby state, AP 2 wakes up only module 2A and the analog Panalog section of the CTSR radio signal processing chain (G010), the other AP components remaining in a standby state. If the Ghost-Fr beacon frame has been stored in storage module 2C, the latter is also woken up in order to transmit the Ghost-Fr beacon frame to the analog Panalog section of the CTSR radio signal processing chain.

[0170] In a first example of implementation of the communication method, the wake-up of the analog Panalog part of the CTSR radio signal processing chain can be triggered automatically according to a given broadcast schedule of a Ghost-Fr phantom beacon frame stored in the non-volatile NVM memory of AP 2 prior to the AP 2 being put into standby mode. As an example, this broadcast schedule of a phantom beacon frame can be stored at the same time as the standby mode schedule and / or the wake-up schedule.

[0171] In a second example of implementing the communication method, the wake-up of the analog Panalog part of the CTSR radio signal processing chain can be triggered by receiving a command from equipment on the NW network. Such a command is, for example, a Wake on LAN command as described earlier in this document, which specifically targets communication module 2A.

[0172] According to yet another example, the wake-up of the analog Panalog part of the CTSR radio signal processing chain can be triggered by the reception of a Wake on LAN command received according to a broadcast schedule of a Ghost-Fr beacon frame. It should be noted that the wake-up The analog Panalog part of the CTSR radio signal processing chain can be triggered by the occurrence of other events.

[0173] In a first particular embodiment, AP 2 receives (G020), from equipment belonging to the NW network, a message including the Ghost-Fr beacon frame intended to be broadcast by AP 2.

[0174] In a second particular embodiment, AP 2 obtains (G030) the Ghost-Fr ghost beacon frame intended to be broadcast by AP 2 by querying the 2C storage module in which the latter was stored during step E030 of the AP 2 standby mode process.

[0175] Regardless of the embodiment implemented, the Ghost-Fr ghost beacon frame to be broadcast is presented in a format ready to be processed by the analog Panalog part of the CTSR radio transmission chain.

[0176] Once the analog Panalog part of the CTSR radio signal processing chain has been woken up and the Ghost-Fr ghost beacon frame to be broadcast has been obtained, the latter is processed by the analog Panalog part of the CTSR radio signal processing chain (G040).

[0177] More particularly, the analog Panalog part of the CTSR radio signal processing chain applies the appropriate analog processing (e.g., filtering, amplification, etc.) known to those skilled in the art to the Ghost-Fr ghost beacon frame, the last step of these analog processing being the transmission of the processed analog signal carrying the information contained in the Ghost-Fr ghost beacon frame by the antenna(s) of AP 2.

[0178] Once the Ghost-Fr beacon frame has been broadcast (G040), the analog Panalog part of the CTSR radio signal processing chain is returned to standby mode (G050). Following this step G050, AP 2 is again in standby mode.

[0179] Just as is the case for the wake-up of the analog Panalog part of the CTSR radio signal processing chain, the putting into standby state of the analog Panalog part of the CTSR radio signal processing chain is, in a first example of implementation, triggered automatically in accordance with the broadcast schedule of a Ghost-Fr phantom beacon frame.

[0180] In a second implementation example, the standby state of the analog Panalog part of the CTSR radio signal processing chain can be triggered by the reception of a command from equipment on the NW network.

[0181] Finally, the standby state of the analog Panalog part of the CTSR radio signal processing chain can be triggered by the reception of a command received in accordance with the broadcast schedule of a phantom beacon frame Ghost-Fr. It should be noted that the standby mode of the analog Panalog part of the CTSR radio signal processing chain can be triggered by the occurrence of other events.

[0182] It should be noted that steps G010 to G050 of the communication process can be implemented at regular or irregular time intervals, or on demand. These steps can be implemented for all or part of the duration of the AP 2's standby state.

[0183] Figure 6 describes the main steps of the ghost beacon frame processing method according to the invention, in a particular embodiment in which it is implemented by the STA 3 and / or by the STA 4 Legacy.

[0184] It should be noted that this method for processing Ghost-Fr beacon frames is implemented only when the AP 2 is in standby mode. More specifically, this method is implemented following the execution of step G010 of the communication method described with reference to [Fig. 5]. The execution of the Ghost-Fr beacon frame processing method according to the invention ends when step G050 of the communication method is implemented.

[0185] In order to indicate its presence and to inform the STAs located in its coverage area that it is in a state of standby, AP 2 regularly broadcasts Ghost-Fr beacon frames.

[0186] In a step F010, an STA located in the coverage area of ​​AP 2 intercepts a Ghost-Fr beacon frame. This step is implemented by module 3A of the STA.

[0187] As discussed above, such a Ghost-Fr beacon frame is a beacon frame in which certain existing, unused fields are used to carry information indicating that AP 2 is in a standby state. This information relating to the standby state of AP 2 can also be included, in an alternative embodiment, in one or more new fields of a beacon frame created specifically for this purpose.

[0188] More particularly, such a Ghost-Fr beacon frame includes in a first embodiment, at least one parameter relating to an exit from the programmed sleep state of AP 2 and at least one connection parameter intended to be filled by STAs seeking to attach to AP 2.

[0189] As a reminder, such a parameter relating to an exit from the programmed sleep state of AP 2 can be: - a date for exiting the AP 2 standby state; - a number of Ghost-Fr phantom frames remaining to be broadcast until AP 2 exits standby state; - a countdown leading to the AP 2 exiting sleep mode.

[0190] The Ghost-Fr phantom beacon frame intercepted by the STA is then processed by the 3B processing module (F020).

[0191] In this first variant of the embodiment, the processing module 3B identifies (F021), in one of the fields of the Ghost-FR phantom frame, the connection parameter intended to be filled by the STA.

[0192] This connection parameter allows STA Legacy 4 to be excluded, which are not able to interpret the Flag parameter included in the Ghost-Fr phantom beacon frame indicating that AP 2 is in a standby state.

[0193] Such a connection parameter can, for example, take the following form. The mandatory "Capability" field includes subfields, among which are the "IBSS" subfield and the "Short Slot Time" subfield. As mentioned previously, simultaneously encoding the value of these two subfields to 1 leads to an inconsistency in Legacy STAs, such as the Legacy 4 STA, which are unable to process such a beacon frame. Due to this inconsistency, a Legacy 4 STA does not populate the connection parameter.

[0194] Faced with such an inability to fill the connection parameter, the STAs 4 Legacy do not seek to multiply attempts to connect to the Wi-Fi network via AP 2.

[0195] Thus when the STA that intercepted the Ghost-Fr phantom beacon frame is unable to fill the connection parameter and turns out to be an STA 4 Legacy, the STA 4 Legacy's processing module 3B identifies (F022) at least one second active AP in whose coverage area the STA 4 Legacy is located and establishes (F023) a connection with this second AP.

[0196] If the STA 4 Legacy is not in the coverage area of ​​any AP other than AP 2, it no longer processes any of the Ghost-Fr phantom beacon frames broadcast by AP 2 until the latter wakes up from its standby state.

[0197] Otherwise, when the STA that intercepted the Ghost-Fr phantom beacon frame is able to interpret these beacon frames in which the subfields "IBSS" and "Short Slot Time" both have the value 1 for what they are, namely Ghost-Fr phantom frames, and is found to be an STA 3 capable of interpreting phantom beacon frames according to the invention, the processing module 3B of the STA 3 determines (F030), from the parameter relating to an exit from the programmed sleep state of the AP 2, a duration remaining until the exit from the programmed sleep state of the AP 2.

[0198] Indeed, as indicated above, the STAs 3 capable of implementing the invention are configured to interpret the beacon frames in which the subfields "IBSS" and "Short Slot Time" both have the value 1 as Ghost-Fr frames broadcast by an AP 2 in a standby state.

[0199] When the time remaining until the AP 2 exits sleep mode exceeds a Thresh threshold, the STA 3 processing module identifies (F031) at least one other active AP in whose coverage area the STA 3 is located and establishes (F032) a connection with that other AP.

[0200] Such a Thresh threshold can be set at several seconds, several minutes, or even several days. For example, the Thresh threshold can be set at 12 hours. Thus, it can be agreed, for example by the manufacturer of the STA 3, that the latter can remain without a connection to an active AP for a period of 12 hours but not beyond.

[0201] As a corollary, when the time remaining until the first access point wakes up is less than or equal to the Thresh threshold, the STA 3 processing module 3B waits for the time remaining until the AP 2 wakes up to expire and establishes (F040) a connection with the AP 2 when it is active again.

[0202] In a second embodiment of the method for processing a ghost beacon frame, the Ghost-Fr ghost beacon frame broadcast by the AP 2 includes only the parameter relating to an exit from the programmed sleep state of the AP 2.

[0203] In this second embodiment of the method for processing a phantom beacon frame, steps F021 to F023 are not implemented. In such a scenario, if the STA that intercepted the phantom frame broadcast by AP 2 is a Legacy STA 4, it is unable to correctly interpret this beacon frame and will repeatedly attempt to connect to the Wi-Fi network via AP 2.

Claims

Demands

1. A communication method implemented by an access point of a telecommunications network in a standby state, the communication method comprising: a. waking up an analog part of a radio signal processing chain intended to be transmitted by the access point; b. broadcasting, by the analog part of the processing chain, at least one beacon frame including at least one parameter indicating that the access point is in a standby state; c. putting the analog part of the processing chain into a standby state.

2. A communication method according to claim 1 in which the beacon frame is processed by a digital part of the processing chain prior to the access point being put into standby mode.

3. A communication method according to claim 1 or claim 2 wherein the sequence of steps a) to c) is implemented: - according to a determined broadcast schedule; or - periodically; or - upon receipt of a command issued by a telecommunications network entity.

4. A communication method according to any one of claims 1 to 3 wherein the beacon frame further comprises a parameter relating to an exit from the programmed sleep state of the access point.

5. A communication method according to claim 4 wherein the parameter relating to the exit from the programmed standby state of the access point belongs to the group comprising: - a date for exiting the standby state of the access point; - a number of beacon frames remaining to be broadcast until the exit from the standby state of the access point; - a countdown leading to the exit from the standby state of the access point.

6. A communication method according to any one of claims 1 to 5 wherein the beacon frame further comprises at least one connection parameter intended to be filled by stations seeking to attach to said access point.

7. Method for putting a telecommunications network access point into standby mode, the standby mode comprising: - obtaining at least one beacon frame including at least one parameter indicating that the access point is in a standby state; - storing the beacon frame; - putting the access point into standby mode.

8. Method of putting an access point into standby mode according to claim 7 wherein obtaining the beacon frame comprises: - generating the beacon frame; - processing the beacon frame by a digital part of a chain for processing radio signals intended to be emitted by the access point.

9. Method of putting an access point into standby mode according to claim 7 wherein obtaining the beacon frame includes receiving the beacon frame from a telecommunications network entity.

10. A method for putting an access point into standby mode according to any one of claims 7 to 9 wherein the putting of the access point into standby mode is triggered by: - ​​the memorization of the beacon frame; or - according to a standby mode schedule.

11. A method for putting an access point into standby mode according to any one of claims 7 to 10, wherein the access point wakes up from standby mode: - upon receiving a command issued by a telecommunications network entity; or according to a schedule for exiting a state of standby.

12. Method of putting an access point into standby mode according to any one of claims 7 to 11 comprising deleting the processed beacon frame when the access point wakes up from standby mode.

13. Beacon frame intended to be broadcast by an access point of a telecommunications network, the beacon frame comprising at least one parameter indicating that the access point is in a standby state.

14. Access point of a telecommunications network comprising: - a beacon frame acquisition module configured to obtain at least one beacon frame including at least one parameter indicating that the access point is in a standby state; - a storage module configured to store the beacon frame; - a standby module configured to put the access point into a standby state; - a communication module configured to: • wake up an analog part of a radio signal processing chain intended to be transmitted by the access point; • broadcast the stored beacon frame; and • put the analog part of the processing chain into a standby state.

15. A method for processing a beacon frame implemented by a station located in a geographical area served, called the coverage area, by a first access point of a telecommunications network which is in a standby state, the method comprising: - receiving at least one beacon frame broadcast by the first access point including at least one parameter indicating that the first access point is in a standby state, - processing the beacon frame.

16. A method for processing a beacon frame according to claim 15, wherein the processing of the beacon frame comprises: - the determination, from information contained in the beacon frame, of a connection parameter intended to be filled in by the station.

17. A method for processing a beacon frame according to claim 16 comprising, when the station does not fulfill the connection parameter: - the identification of at least one second active access point in the coverage area of ​​which it is located, - the establishment of a connection with the second access point.

18. A method for processing a beacon frame according to claim 15 or 16 in which the processing of the beacon frame comprises: - determining, from information contained in the beacon frame, a time remaining until the first access point exits the standby state.

19. A method for processing a beacon frame according to claim 18 comprising, when the time remaining until the first access point exits the standby state exceeds a threshold: - the identification of at least one third active access point in whose coverage area it is located, - the establishment of a connection with the third access point.

20. A method for processing a beacon frame according to claim 18 comprising, when the time remaining until the first access point exits the standby state is less than or equal to the threshold: - establishing a connection with the first access point upon expiry of the time remaining until the first access point exits the standby state.

21. Station located in a geographical area served by an access point of a telecommunications network in a standby state, the station comprising: - a receiving module configured to receive at least one beacon frame broadcast by the access point including at least one parameter indicating that the access point is in a standby state; a processing module configured to process the tag frame.

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