Access point and terminal device

Abstract

An access point according to one aspect of the present invention comprises a wireless communication unit, a notification unit, and a communication control unit. The wireless communication unit is configured to wirelessly communicate with a terminal device. The notification unit notifies the network type of a basic service set (BSS) to which the access point belongs via the wireless communication unit. If the terminal device is an object to be controlled in the network type, the communication control unit controls the wireless communication unit such that the wireless communication unit performs data communication with the terminal device using a parameter corresponding to the network type.

Description

Access point and terminal device

[0001] The present invention relates to wireless communications.

[0002] Wireless communications are used in factories, logistics, smart agriculture, and other applications. Wireless networks built for specific applications, such as factories, logistics, and smart agriculture, are used by various terminals, such as automated guided vehicles (AGVs), smartphones, and personal computers (PCs). Specific terminals, such as AGVs, require high communication quality based on various key performance indicators (KPIs), such as low latency. The communication quality of specific terminals, such as AGVs, may be degraded by wireless communications with other terminals, such as smartphones, and may not be able to meet the communication quality required by the specific terminal.

[0003] IEEE Std 802.11ax-2021, “26.17.3 BSS color”, pp.458-461, May 19, 2021.IEEE Std 802.11-2020, “9.4.2.91 Interworking element”, pp.1196-1197, February 26, 2021.

[0004] In a wireless network, it is required to be able to treat a specific terminal such as an AGV as a control target so that the communication quality required by the specific terminal can be satisfied.

[0005] An object of the present invention is to provide a technique for ensuring the communication quality requirements of a terminal to be controlled.

[0006] An access point according to one aspect of the present invention includes a wireless communication unit, a notification unit, and a communication control unit. The wireless communication unit is configured to communicate wirelessly with a terminal device. The notification unit notifies, via the wireless communication unit, the network type of a basic service set (BSS) to which the access point belongs. If the terminal device is a control target based on the network type, the communication control unit controls the wireless communication unit to perform data communication with the terminal device using parameters corresponding to the network type.

[0007] According to the present invention, a technique is provided for ensuring the communication quality requirements of a terminal to be controlled.

[0008] FIG. 1 is a diagram showing a wireless network according to an embodiment. FIG. 2 is a diagram for explaining a wireless communication method according to an embodiment. FIG. 3 is a diagram showing an example of a parameter table according to an embodiment. FIG. 4 is a diagram showing another example of a parameter table according to an embodiment. FIG. 5 is a block diagram showing a hardware configuration of an access point according to an embodiment. FIG. 6 is a block diagram showing a hardware configuration of a terminal according to an embodiment. FIG. 7 is a block diagram showing a functional configuration of an access point according to an embodiment. FIG. 8 is a block diagram showing a functional configuration of a terminal according to an embodiment. FIG. 9 is a flowchart showing a wireless communication method according to an embodiment. FIG. 10 is a sequence diagram showing the procedure of the wireless communication method according to an embodiment.

[0009] Hereinafter, embodiments of the present invention will be described with reference to the drawings. The embodiments exemplify devices and methods for embodying the technical ideas of the invention, and are not intended to limit the scope of the invention. The drawings are schematic or conceptual. Hereinafter, components having similar functions or configurations may be assigned the same reference numerals. In order to distinguish between components having similar functions or configurations, a subscript may be added to the reference numeral. The subscript is added after a hyphen "-" is inserted.

[0010] An example in which the wireless communication method according to the embodiment is applied to the IEEE 802.11 standard will be described. The wireless communication method according to the embodiment is not limited to the IEEE 802.11 standard, but can also be applied to other wireless communication standards.

[0011] The IEEE 802.11 standard defines the MAC sublayers of Layer 1 and Layer 2 of the OSI (Open Systems Interconnection) reference model, which divides communication functions into seven layers: Layer 1: physical layer, Layer 2: data link layer, Layer 3: network layer, Layer 4: transport layer, Layer 5: session layer, Layer 6: presentation layer, and Layer 7: application layer.

[0012] The data link layer includes a logical link control (LLC) layer and a media access control (MAC) layer. The LLC layer generates LLC packets by adding a destination service access point (DSAP) header and a source service access point (SSAP) header to data input from a higher layer. The MAC layer generates MAC frames by adding a MAC header to LLC packets. MAC frames are sometimes called MAC protocol data units (MPDUs). The physical layer generates wireless frames by adding a preamble to MAC frames. Wireless frames are sometimes called physical layer (PHY) protocol data units (PPDUs).

[0013] In a wireless network according to an embodiment, each terminal is treated as either a controlled terminal or a non-controlled terminal. Wireless access parameters are controlled so that a controlled terminal performs data communication using parameters different from those used by non-controlled terminals. The controlled terminal is permitted to use a predetermined function, while the non-controlled terminal is prohibited from using the predetermined function. This configuration allows the controlled terminal to perform data communication with higher priority than the non-controlled terminal. As a result, degradation of the communication quality of the controlled terminal due to wireless communication by the non-controlled terminal can be suppressed, and the communication quality required by the controlled terminal can be satisfied. While an example of controlling both parameters and function usage is described here, only one of the parameters and function usage may be controlled. Hereinafter, a controlled terminal may be referred to as a controlled terminal, and a non-controlled terminal may be referred to as a non-controlled terminal.

[0014] The IEEE 802.11ax standard defines a BSS color for identifying a basic service set (BSS). The BSS color is stored in the preamble of a wireless frame, and a wireless station (e.g., an access point or a terminal) receiving the wireless frame checks the BSS color to determine whether the wireless frame originates from its own BSS or another BSS (also known as an overlapping basic service set (OBSS)). During carrier sensing based on CSMA / CA (carrier sense multiple access with collision avoidance), the wireless station changes the preamble detection (PD) threshold used to determine channel usage status depending on whether the received wireless frame originates from its own BSS or an OBSS. Specifically, the wireless station applies a normal PD threshold when the received wireless frame originates from its own BSS, and applies a low-sensitivity PD threshold (specifically, a PD threshold higher than the normal PD threshold) when the received wireless frame originates from an OBSS. This makes it possible to alleviate the exposed terminal problem in which a wireless station waits for transmission due to communication from an OBSS that is unrelated to the wireless station.

[0015] The BSS color is used to identify the BSS and to change the PD threshold depending on whether the radio frame originates from the own BSS or the OBSS. The BSS color cannot provide control that takes into account the requirements of the terminal (e.g., low latency).

[0016] The IEEE 802.11u standard also defines a mechanism for reporting the network type of a BSS by the Access Network Type in the Access Network Options field in the Interworking element. The Access Network Type is a mechanism for reporting the network type, such as a network requiring billing, a network requiring additional authentication, or a private network, before a terminal connects, and does not define control according to the network type.

[0017] Fig. 1 schematically illustrates a wireless network 40 according to one embodiment. As illustrated in Fig. 1, the wireless network 40 includes an access point (AP) 10 and multiple terminals 20. In the example illustrated in Fig. 1, four terminals 20-1 to 20-4 are shown as the terminals 20.

[0018] The access point 10 is an access point for a wireless local area network (LAN). The access point 10 is also called a base station. The access point 10 is connected to a communication network (not shown) that may include the Internet and / or an intranet. For example, the wireless network 40 may be part of an intranet established in a factory.

[0019] The terminal 20 is a terminal device equipped with a wireless module that functions as a client of a wireless LAN. Examples of terminal devices include a personal computer, a smartphone, and an automated guided vehicle (AGV). An AGV is a self-propelled robot that can be used, for example, to transport goods. In the example shown in FIG. 1, the terminals 20-1 and 20-2 are AGVs, and the terminals 20-3 and 20-4 are smartphones.

[0020] Terminals 20 (specifically, terminals 20-1 to 20-4) are wirelessly connected to the access point 10. Specifically, a wireless link is logically established between the access point 10 and each terminal 20, and data communication is possible between the access point 10 and each terminal 20 using the established wireless link. The access point 10 and the terminals 20 form a BSS (basic service set). In other words, the access point 10 and the terminals 20 belong to the same BSS. The wireless network 40 corresponds to the BSS.

[0021] Terminal 20 communicates with devices on the communication network via access point 10. For example, each of terminals 20-1 and 20-2 receives control data for controlling operations, including movement, from a control device (not shown) included in the intranet via access point 10.

[0022] In the wireless network 40, the terminals 20-1 and 20-2 require low latency in data communication, for example, for smooth operation. The terminals 20-1 and 20-2 are controlled terminals, and the terminals 20-3 and 20-4 are non-controlled terminals. The wireless network 40 enables the terminals 20-1 and 20-2 to exchange data with the access point 10 with low latency, as described below.

[0023] The access point 10 sets the network type of its own BSS (specifically, the BSS to which the access point 10 belongs). For example, the access point 10 registers a network type selected from predetermined network types by a user managing the wireless network 40 as the network type of its own BSS. The predetermined network types may include, for example, a low latency network in addition to the network types defined in IEEE 802.11u. The network types defined in IEEE 802.11u are eight network types: "Private network," "Private network with guest access," "Chargeable public network," "Free public network," "Personal device network," "Emergency service only network," "Test or experimental network," and "Wildcard." A low latency network is a network that provides low-latency data communication to a terminal 20 that is set or designated as a control target. In a low latency network, one or more parameters relating to wireless access are controlled depending on whether the terminal 20 is a control target or not.

[0024] A terminal 20 can be set as a controlled object that allows prioritized data communication in a specific type of network, such as a low-latency network. The controlled terminal 20 performs data communication using parameters that are more advantageous than normal parameters. For example, the controlled terminal 20 performs carrier sensing using enhanced distributed channel access (EDCA) parameters set to values ​​that make it easier to acquire a transmission right. The controlled terminal 20 can also use pre-specified functions that contribute to improving communication quality, such as low latency and / or high throughput. On the other hand, a non-controlled terminal 20 performs data communication using normal parameters. For example, the non-controlled terminal 20 performs carrier sensing using the same EDCA parameters as those used in other types of networks, such as a public network. The non-controlled terminal 20 is also prohibited from using functions that are available to the controlled terminal 20.

[0025] Access points (not shown) present around the access point 10 receive a beacon including network type information from the access point 10. If the network type information indicates a specific network type such as a low-latency network, the access point receiving the beacon may control parameters, such as by using a frequency channel different from the frequency channel used in the BSS of the access point 10. By the access point 10 broadcasting the network type of its own BSS in this way, surrounding access points can control parameters in accordance with the network type of the BSS of the access point 10.

[0026] 2, a case will be described in which terminal 20-5, which is an AGV, newly joins wireless network 40. Here, it is assumed that the network type of the BSS to which access point 10 belongs is set to a low-latency network, and terminal 20-5 is set to be controlled in the low-latency network.

[0027] The access point 10 broadcasts the network type of its own BSS using a management frame such as a beacon frame (hereinafter referred to as a beacon). For example, the access point 10 transmits (broadcasts) a beacon including network type information indicating the network type of its own BSS. For example, the network type information may be broadcast using an interworking element in the beacon. In the example described here, the network type information indicates that the network type of the BSS to which the access point 10 belongs is a low-latency network.

[0028] The terminal 20-5 receives a beacon from the access point 10. Based on the network type information included in the received beacon, the terminal 20-5 recognizes that the network type of the BSS to which the access point 10 belongs is a low-latency network. When wirelessly connecting to the access point 10, the terminal 20-5 notifies the access point 10 that it is a control target in the low-latency network. This notification may be performed using a management frame such as a probe request frame or an association request frame. For example, this notification may be performed using an interworking element in the probe request frame. Based on the notification from the terminal 20-5, the access point 10 recognizes that the terminal 20-5 is a control target in the low-latency network. Hereinafter, the probe request frame and the association request frame will be referred to as a probe request and an association request.

[0029] Thereafter, authentication and association are performed between the access point 10 and the terminal 20-5, and a wireless link between the access point 10 and the terminal 20-5 is established. After the wireless link is established, the terminal 20-5 exchanges data with the access point 10 using parameters according to the network type. Specifically, the terminal 20-5 exchanges data with the access point 10 using parameters defined for controlled terminals in a low-latency network.

[0030] The mechanism by which the access point 10 recognizes that the terminal 20-5 is a control target is not limited to a handshake using a probe request or the like as described above, but may also be pre-registration of a media access control (MAC) address or other authentication means. For example, the MAC address of the control target terminal may be pre-registered in the access point 10, and the access point 10 may determine whether the terminal 20 is a control target in the low-latency network by comparing the source address included in a management frame (e.g., an association request) received from the terminal 20 with the pre-registered MAC address. Specifically, the access point 10 recognizes that the terminal 20 is a control target when the source address included in the management frame received from the terminal 20 matches the pre-registered MAC address, and recognizes that the terminal 20 is not a control target when the source address included in the management frame received from the terminal 20 does not match the pre-registered MAC address.

[0031] Fig. 3 schematically illustrates an example of a parameter table according to an embodiment. The parameter table illustrated in Fig. 3 includes parameter values ​​to be applied to controlled terminals in a low-latency network and parameter values ​​to be applied to non-controlled terminals in the low-latency network. In the example illustrated in Fig. 3, parameters related to radio access include CWmin, CWmax, a modulation and coding scheme (MCS) index range, TXOPLimit, and a preamble detection (PD) threshold. CWmin, CWmax, and TXOPLimit are included in EDCA parameters. The values ​​of CWmin, CWmax, and TXOPLimit are set for each access category.

[0032] CWmin and CWmax are parameters that specify the minimum and maximum values ​​of the contention window. The contention window is a parameter used to determine backoff (transmission waiting time for collision avoidance). The smaller the CWmin and CWmax values, the easier it is to obtain the transmission right. The CWmin and CWmax values ​​for non-controlled terminals are set to the same values ​​as the specified values ​​used in other types of networks such as private networks. The CWmin and CWmax values ​​for controlled terminals are set to values ​​that are more advantageous than the CWmin and CWmax values ​​for non-controlled terminals. Specifically, the CWmin and CWmax values ​​for controlled terminals are set to values ​​that are smaller than the CWmin and CWmax values ​​for non-controlled terminals.

[0033] The MCS index range is a parameter that specifies the range of the MCS index and is specified by a minimum value and a maximum value. The MCS index is a numerical value that represents a combination of a modulation method and a coding rate, and an MCS corresponding to the MCS index range is selectively used. The MCS index range for non-controllable terminals is a specified value, and the MCS index range for controlled terminals is determined based on the distance between the access point 10 and the controlled terminal and the required throughput of the controlled terminal, etc. If the controlled terminal requires a higher throughput, the minimum and maximum values ​​of the MCS index are set to higher values.

[0034] TXOPLimit is a parameter that specifies the upper limit of the channel occupation period. The TXOPLimit value for non-controlled terminals is set to a value that is the same as or smaller than the specified value used in other types of networks such as private networks. The TXOPLimit value for controlled terminals is set to a value that is more advantageous than the TXOPLimit value for non-controlled terminals. Specifically, the TXOPLimit value for controlled terminals is set to a value larger than the TXOPLimit value for non-controlled terminals, for example, a value larger than the specified value.

[0035] The PD threshold for the non-controlled terminal is set to a specified value. The PD threshold for the controlled terminal is set to a value that is more sensitive than the value applied to the non-controlled terminal. Specifically, the PD threshold for the controlled terminal is set to a value that is greater than the specified value.

[0036] Furthermore, the parameter table indicates functions that are available to controlled terminals in a low-latency network and that are unavailable to non-controlled terminals in a low-latency network. In the example shown in Figure 3, controlled terminals are permitted to use functions A to Z, and non-controlled terminals are prohibited from using functions A to Z. In Figure 3, "○" indicates that the function is available, and "×" indicates that the function is unavailable. Each of functions A to Z may be a function that contributes to prioritized data communication, such as a function that provides low latency, such as R-TWT (restricted target wake time) considered in 802.11be, or preemption considered in 802.11bn, or a function that provides high throughput.

[0037] The parameter table shown in FIG. 3 may be stored in advance in the terminal 20 or may be notified by the AP 10. When the AP 10 broadcasts the parameter table in a beacon, the CWmin, CWmax, MCS index range, TXOPLimit, PD threshold, and MCS index range are set to values ​​to be applied to non-controllable terminals, and the capabilities of functions (functions A to Z) that are prohibited from use by non-controllable terminals are set to "No." The access point 10 then broadcasts values ​​to be applied to controllable terminals for CWmin, CWmax, TXOPLimit, PD threshold, and MCS index range in a probe response frame, which is a response to a probe request received from a controllable terminal. For example, the access point 10 writes valid values ​​in the EDCA Parameter Set element in the probe response frame. Hereinafter, the probe response frame will be referred to as a probe response.

[0038] A plurality of QoS (quality of service) classes for classifying the controlled terminals may be defined, and parameter values ​​may be prepared for each QoS class. The controlled terminals are classified into one of the QoS classes based on, for example, the terminal type, the average delay required by the controlled terminal, the maximum delay required by the controlled terminal, and the average throughput required by the controlled terminal. For example, the access point 10 may classify the terminals 20 based on information received from the terminals 20.

[0039] FIG. 4 schematically illustrates another example of a parameter table according to an embodiment. The parameter table illustrated in FIG. 4 includes parameter values ​​to be applied to controlled terminals classified as QoS class 1, parameter values ​​to be applied to controlled terminals classified as QoS class 2, parameter values ​​to be applied to controlled terminals classified as QoS class 3, parameter values ​​to be applied to controlled terminals classified as QoS class 4, and parameter values ​​to be applied to non-controlled terminals. In the example illustrated in FIG. 4 , parameter values ​​are set so that the priority of data communication increases in the order of QoS class 1, QoS class 2, QoS class 3, and QoS class 4. Note that a parameter value for a certain QoS class may be more advantageous than a parameter value for a lower QoS class, or may be the same value as a parameter value for the lower QoS class. For example, the CWmin value for QoS class 1 may be equal to or smaller than the CWmin value for QoS class 2.

[0040] Fig. 5 shows an example of a hardware configuration of the access point 10. As shown in Fig. 5, the access point 10 includes a central processing unit (CPU) 11 as a processor, a read only memory (ROM) 12, a random access memory (RAM) 13, a wireless communication module 14, and a wired communication module 15. The CPU 11 is connected to the ROM 12, the RAM 13, the wireless communication module 14, and the wired communication module 15 via a bus.

[0041] The CPU 11 is an integrated circuit capable of executing various programs and controls the overall operation of the access point 10. The ROM 12 is a non-volatile semiconductor memory that stores programs and control data for controlling the access point 10. The RAM 13 is a volatile semiconductor memory that is used as a work area for the CPU 11. At least a portion of the processing described for the access point 10 can be implemented by the CPU 11 executing the programs stored in the ROM 12.

[0042] The wireless communication module 14 is a circuit configured to be able to transmit and receive wireless signals via an antenna, and is used for communication with the terminal 20. The wired communication module 15 is a circuit used for transmitting and receiving data and the like using electrical signals, and is used for communication with a communication network.

[0043] 5 is an example, and the access point 10 may have a hardware configuration different from that shown in Fig. 5. For example, in an example in which the access point 10 wirelessly communicates with a communication network, the wired communication module 15 may be omitted.

[0044] Fig. 6 shows an example of a hardware configuration of the terminal 20. As shown in Fig. 6, the terminal 20 includes a CPU 21 as a processor, a ROM 22, a RAM 23, a wireless communication module 24, and a storage device 25. The CPU 21 is connected to the ROM 22, the RAM 23, the wireless communication module 24, and the storage device 25 via a bus.

[0045] The CPU 21 is an integrated circuit capable of executing various programs and controls the overall operation of the terminal 20. The ROM 22 is a non-volatile semiconductor memory that stores programs and control data for controlling the terminal 20. The RAM 23 is, for example, a volatile semiconductor memory that is used as a work area for the CPU 21. At least a portion of the processing described for the terminal 20 can be implemented by the CPU 21 executing the programs stored in the ROM 22.

[0046] The wireless communication module 24 is a circuit configured to be able to transmit and receive wireless signals via an antenna, and is used for communication with the access point 10. The storage device 25 is a non-volatile storage device, and stores, for example, system software, application software, data, etc. of the terminal 20.

[0047] Note that the hardware configuration shown in Fig. 6 is an example, and the terminal 20 may have a hardware configuration different from that shown in Fig. 6. For example, if the terminal 20 is an AGV, the terminal 20 further includes a moving mechanism such as a dolly. Also, if the terminal 20 is a smartphone or a PC, the terminal 20 further includes a display device or the like.

[0048] Fig. 7 schematically illustrates an example of the functional configuration of the access point 10. As illustrated in Fig. 7, the access point 10 includes an upper layer processing unit 110, an LLC processing unit 120, a MAC processing unit 130, a wireless communication unit 140, and a management unit 150. The upper layer processing unit 110 and the LLC processing unit 120 may be realized, for example, by a combination of the CPU 11 and a wired communication module 15. The MAC processing unit 130, the wireless communication unit 140, and the management unit 150 may be realized, for example, by the wireless communication module 14 or by a combination of the CPU 11 and the wireless communication module 14.

[0049] Upper layer processing unit 110 communicates with the communication network, receives data addressed to terminal 20 from the communication network, and sends the received data to LLC processing unit 120.

[0050] The LLC processing unit 120 performs LLC layer processing. The LLC processing unit 120 receives data from the upper layer processing unit 110 and adds a DSAP header, an SSAP header, and the like to the received data to generate LLC packets.

[0051] The MAC processing unit 130 performs MAC layer processing. For example, the MAC processing unit 130 receives LLC packets from the LLC processing unit 120, adds a MAC header and the like to the received LLC packets to generate MAC frames (specifically, data frames), and sends the generated MAC frames to the wireless communication unit 140. The MAC processing unit 130 also receives MAC frames (specifically, management frames or control frames) from the management unit 150 and sends the received MAC frames to the wireless communication unit 140. Examples of management frames generated by the management unit 150 include beacons, probe requests, association requests, and the like.

[0052] The wireless communication unit 140 performs PHY layer processing. The wireless communication unit 140 is configured to transmit and receive wireless signals. For example, the wireless communication unit 140 receives a MAC frame from the MAC processing unit 130, generates a wireless frame by adding a preamble or the like to the received MAC frame, converts the wireless frame into a wireless signal by performing a predetermined modulation process, and emits the wireless signal via an antenna. The predetermined modulation process includes, for example, convolutional coding, interleaving, subcarrier modulation, inverse fast Fourier transform (IFFT), orthogonal frequency division multiplexing (OFDM) modulation, and frequency conversion.

[0053] The wireless communication unit 140 receives wireless signals from the terminal 20 via an antenna and performs a predetermined demodulation process on the received wireless signals to obtain wireless frames. The predetermined demodulation process includes, for example, frequency conversion, OFDM demodulation, fast Fourier transform (FFT), subcarrier demodulation, deinterleaving, and Viterbi decoding. The wireless communication unit 140 then extracts MAC frames (specifically, data frames, management frames, or control frames) from the wireless frames and sends the extracted MAC frames to the MAC processing unit 130.

[0054] When MAC processing unit 130 receives a data frame from wireless communication unit 140, it extracts an LLC packet from the received data frame and sends the extracted LLC packet to LLC processing unit 120. When MAC processing unit 130 receives a management frame or control frame from wireless communication unit 140, it sends the received management frame or control frame to management unit 150.

[0055] LLC processing unit 120 receives LLC packets from MAC processing unit 130, extracts data from the received LLC packets, and sends the extracted data to upper layer processing unit 110. Upper layer processing unit 110 receives data from LLC processing unit 120 and transmits the received data to the communication network.

[0056] The management unit 150 manages the connection with the terminal 20. In the example shown in Fig. 7, the management unit 150 includes a setting unit 151, a beacon transmitting unit 152, a connection control unit 153, and a communication control unit 154.

[0057] The setting unit 151 sets the network type of the BSS to which the access point 10 belongs. For example, various information such as the network type can be set in the access point 10 by a user operating an external computer. The setting unit 151 registers the network type indicated by the information received from the external computer as the network type of the BSS to which the access point 10 belongs. In this embodiment, a low-latency network is registered as the network type of the BSS to which the access point 10 belongs.

[0058] The beacon transmitter 152 generates a beacon and transmits it via the wireless communication unit 140. The beacon includes various information necessary for communication. The beacon may include, for example, EDCA parameters, capability information, network type information, etc. The EDCA parameters may include, for each access category, a CWmin value, a CWmax value, an AIFS value, and a TXOPLimit value. The capability information indicates the capability of each function. Specifically, the capability information indicates whether each function is available. The network type information indicates the network type of the BSS of the access point 10.

[0059] The beacon transmitting unit 152 corresponds to a notifying unit that notifies, via the wireless communication unit 140, the network type of the BSS to which the access point 10 belongs.

[0060] The connection control unit 153 performs a connection procedure. For example, the connection control unit 153 waits for a management frame such as a probe request or an association request from the terminal 20.

[0061] When the connection control unit 153 receives an association request from the terminal 20, it transmits an association response frame to the terminal 20 in response to the association request from the terminal 20. This establishes a wireless link between the access point 10 and the terminal 20. Hereinafter, the association response frame will be referred to as an association response.

[0062] When the connection control unit 153 receives a probe request from the terminal 20, it determines whether the terminal 20 is a control target in the low-latency network based on information included in the received probe request. In response to receiving the probe request, the connection control unit 153 transmits a probe response to the terminal 20. When it is determined that the terminal 20 is a control target in the low-latency network, the probe response may include information indicating that the access point 10 has recognized that the terminal 20 is a control target in the low-latency network. In one example, when the connection control unit 153 determines that the terminal 20 is a control target in the low-latency network, it may transmit a probe response to the terminal 20 that includes parameters to be applied to control target terminals and information indicating that a predetermined function is available. When it determines that the terminal 20 is not a control target in the low-latency network, it may transmit a probe response to the terminal 20 that includes parameters to be applied to non-control target terminals and information indicating that a predetermined function is unavailable. After transmitting the probe response to the terminal 20, the connection control unit 153 waits for an association request from the terminal 20. The connection control unit 153 receives an association request from the terminal 20, and in response to the receipt of the association request from the terminal 20, transmits an association response to the terminal 20. As a result, a wireless link is established between the access point 10 and the terminal 20.

[0063] The connection control unit 153 functions as a determination unit that determines whether the terminal 20 is a control target in the low-latency network. For example, the connection control unit 153 acquires information indicating whether the terminal 20 is a control target in the network type of the BSS to which the access point 10 belongs from the terminal 20 via the wireless communication unit 140. Furthermore, if the MAC address of the control target terminal is pre-registered in the connection control unit 153, the connection control unit 153 determines whether the terminal 20 is a control target in the low-latency network by comparing the source address included in the management frame received from the terminal 20 with the pre-registered MAC address.

[0064] The communication control unit 154 controls data communication with the terminal 20 via the wireless communication unit 140. Specifically, when the terminal 20 is not a control target in the network type of the BSS to which the access point 10 belongs, the communication control unit 154 controls the wireless communication unit 140 so that data communication with the terminal 20 is performed using normal parameters without using a predetermined function, and when the terminal 20 is a control target in the network type of the BSS to which the access point 10 belongs, the communication control unit 154 controls the wireless communication unit 140 so that data communication with the terminal 20 is performed using parameters that are more advantageous than the normal parameters and a predetermined function.

[0065] FIG. 8 schematically illustrates an example of the functional configuration of the terminal 20. The terminal 20 illustrated in FIG. 8 corresponds to any one or each of the terminals 20-1 to 20-5 illustrated in FIGS. 1 and 2. FIG. 8 illustrates a functional configuration related to wireless communication. As illustrated in FIG. 8, the terminal 20 includes an upper layer processing unit 210, an LLC processing unit 220, a MAC processing unit 230, a wireless communication unit 240, and a management unit 250. The upper layer processing unit 210 and the LLC processing unit 220 may be realized by, for example, the CPU 21. The MAC processing unit 230, the wireless communication unit 240, and the management unit 250 may be realized by, for example, the wireless communication module 24 or a combination of the CPU 21 and the wireless communication module 24.

[0066] The upper layer processing unit 210 executes an application that exchanges data with a computer on a communication network connected to the access point 10. The upper layer processing unit 210 sends data generated by the application to the LLC processing unit 220.

[0067] The LLC processing unit 220 performs LLC layer processing. For example, the LLC processing unit 220 receives data from the upper layer processing unit 210 and adds a DSAP header, an SSAP header, and the like to the received data to generate an LLC packet.

[0068] The MAC processing unit 230 performs MAC layer processing. For example, the MAC processing unit 230 receives LLC packets from the LLC processing unit 220, adds a MAC header and the like to the received LLC packets to generate MAC frames (specifically, data frames), and sends the generated MAC frames to the wireless communication unit 240. The MAC processing unit 230 also receives MAC frames (specifically, management frames or control frames) from the management unit 250 and sends the received MAC frames to the wireless communication unit 240. Examples of management frames generated by the management unit 250 include beacons, probe responses, association responses, and the like.

[0069] The wireless communication unit 240 performs PHY layer processing. The wireless communication unit 240 is configured to transmit and receive wireless signals. For example, the wireless communication unit 240 receives a MAC frame from the MAC processing unit 230, adds a preamble or the like to the received MAC frame to generate a wireless frame, converts the wireless frame into a wireless signal by performing a predetermined modulation process, and emits the wireless signal via an antenna.

[0070] The wireless communication unit 240 also receives wireless signals from the access point 10 via the antenna, performs a predetermined demodulation process on the received wireless signals, and obtains wireless frames. The wireless communication unit 240 then extracts MAC frames from the wireless frames and sends the extracted MAC frames to the MAC processing unit 230.

[0071] When MAC processing unit 230 receives a data frame from wireless communication unit 240, it extracts an LLC packet from the received data frame and sends the extracted LLC packet to LLC processing unit 220. When MAC processing unit 230 receives a management frame or control frame from wireless communication unit 240, it sends the received management frame or control frame to management unit 250.

[0072] The LLC processing unit 220 receives LLC packets from the MAC processing unit 230 , extracts data from the received LLC packets, and sends the extracted data to the upper layer processing unit 210 .

[0073] The management unit 250 manages the connection with the access point 10. In the example shown in Fig. 8, the management unit 250 includes a setting unit 251, a beacon receiving unit 252, a connection control unit 253, and a communication control unit 254.

[0074] The setting unit 251 sets the network type to be controlled. In one example, the setting unit 251 sets the network type to be controlled by the terminal 20 based on a user input. In another example, the setting unit 251 sets the network type to be controlled based on an application installed in the terminal 20. For example, when an application associated with a low-latency network is installed in the terminal 20, the setting unit 251 sets the low-latency network as the network type to be controlled.

[0075] The beacon receiving unit 252 waits for a beacon from the access point 10. The beacon receiving unit 252 receives a beacon from the access point 10 and sends the received beacon to the connection control unit 253.

[0076] The beacon receiving unit 252 corresponds to a network type information acquiring unit that acquires, from the access point 10, network type information indicating the network type of the BSS to which the access point 10 belongs.

[0077] The connection control unit 253 performs a connection procedure. For example, the connection control unit 253 checks information included in the beacon received by the beacon receiving unit 252. For example, the connection control unit 253 identifies the network type of the BSS to which the access point 10 belongs based on the network type information included in the beacon.

[0078] A case will be described where the terminal 20 is a control target in a low-latency network. The connection control unit 253 determines whether the network type of the BSS to which the access point 10 belongs is a low-latency network. If the network type of the BSS to which the access point 10 belongs is not a low-latency network, the connection control unit 253 transmits an association request to the access point 10 and receives an association response from the access point 10 as a response to the association request. This establishes a wireless link between the access point 10 and the terminal 20.

[0079] If the network type of the BSS to which the access point 10 belongs is a low-latency network, the connection control unit 253 transmits a probe request to the access point 10, the probe request including information indicating that the terminal 20 is a control target in the low-latency network. The connection control unit 253 receives a probe response from the access point 10, which is a response to the probe request. The probe response may include information indicating that the access point 10 has recognized that the terminal 20 is a control target in the low-latency network. After receiving the probe response, the connection control unit 253 transmits an association request to the access point 10. The connection control unit 253 receives an association response from the access point 10, which is a response to the association request. As a result, a wireless link is established between the access point 10 and the terminal 20.

[0080] The communication control unit 254 controls data communication with the access point 10 via the wireless communication unit 240. Specifically, when the terminal 20 is not a control target in the network type of the BSS to which the access point 10 belongs, the communication control unit 254 controls the wireless communication unit 240 so that data communication with the access point 10 is performed using normal parameters without using predetermined functions, and when the terminal 20 is a control target in the network type of the BSS to which the access point 10 belongs, the communication control unit 254 controls the wireless communication unit 240 so that data communication with the access point 10 is performed using parameters that are more advantageous than normal parameters and predetermined functions.

[0081] Fig. 9 shows an overview of a wireless communication method according to the embodiment. The wireless communication method shown in Fig. 9 is executed in the wireless network 40 shown in Fig. 1. The network type of the BSS to which the access point 10 belongs is set in the access point 10.

[0082] The terminal 20 sets the type of network to be controlled (step S901). For example, the terminal 20 sets the type of network to be controlled based on an input from the user of the terminal 20.

[0083] If the network type of the BSS to which the access point 10 belongs matches the network type of the terminal 20 to be controlled (step S902; Yes), parameters for the terminal to be controlled are applied to data communication between the access point 10 and the terminal 20, and the use of specified functions such as preemption is permitted (step S903).

[0084] On the other hand, if the network type of the BSS to which the access point 10 belongs does not match the network type of the terminal 20 to be controlled (step S902; No), general-purpose parameters may be applied to data communication between the access point 10 and the terminal 20 (step S904). In this case, the use of certain functions may be prohibited. For example, the access point 10 notifies the terminal 20 of parameters and supported functions for terminals not to be controlled as default values.

[0085] The parameters for the controlled terminal may be more advantageous than the general-purpose parameters. For example, the parameters for the controlled terminal are parameters that enable data communication with lower latency than data communication using the general-purpose parameters. The parameters for the controlled terminal are set to a value a １ and the general parameters include CWmin set to the value a １ a value greater than ２ The parameters for the controlled terminal may include CWmin set to value b １ and the general parameters include CWmax set to value b １ a value greater than b ２The parameters for the controlled terminal may include a CWmax set to a value c １ and the general parameters include TXOPLimit set to value c １ A value c smaller than ２ The parameters for the controlled terminal may include a TXOPLimit set to the value d １ and the generic parameters include the PD threshold set to the value d １ A value d smaller than ２ The parameters for the controlled terminal may include a PD threshold set to a value e １ and the general parameters include the maximum MCS index set to the value e １ A value e smaller than ２ The maximum MCS index may be set to .

[0086] 10 is a schematic diagram illustrating an example of a procedure of the wireless communication method according to the embodiment. Here, it is assumed that the network type of the BSS to which the access point 10 belongs and the network type of the network to be controlled by the terminal 20 are both low-latency networks.

[0087] As shown in FIG. 10, the access point 10 periodically broadcasts a beacon including network type information indicating that the network type of its own BSS is a low-latency network (step S1001).

[0088] The terminal 20 receives a beacon from the access point 10 (step S1002). For example, when the terminal 20 is within the communication range of the access point 10, the power of the terminal 20 is turned on, the wireless communication module 24 of the terminal 20 becomes active, and the terminal 20 begins to receive a beacon from the access point 10.

[0089] The terminal 20 recognizes from the network type information included in the received beacon that the network type of the BSS of the access point 10 is a low-latency network (step S1003).

[0090] The terminal 20 transmits a probe request including information indicating that the terminal 20 is a control target in the low-latency network to the access point 10 (step S1004). The access point 10 receives the probe request from the terminal 20 (step S1005).

[0091] The access point 10 recognizes from the information included in the probe request received from the terminal 20 that the terminal 20 is a target of control of the low latency network (step S1006).

[0092] The access point 10 transmits a probe response to the terminal 20 (step S1007). The terminal 20 receives the probe response from the access point 10 (step S1008). The probe response may include predetermined parameters related to the control target in the low-latency network.

[0093] The terminal 20 transmits an association request to the access point 10 (step S1009). The access point 10 receives the association request from the terminal 20 (step S1010).

[0094] The access point 10 transmits an association response to the terminal 20 (step S1011). The terminal 20 receives the association response from the access point 10 (step S1012). The association response may include predetermined parameters related to the control target in the low-latency network. This establishes a wireless link between the access point 10 and the terminal 20.

[0095] Thereafter, the access point 10 and the terminal 20 perform data communication with each other using predetermined parameters related to the control target in the low-latency network (step S1013). For example, the terminal 20 applies the parameters included in the probe response received in step S1008 or the association response received in step S1012 to the wireless communication unit 240.

[0096] As described above, in this embodiment, the network type of the BSS to which the access point 10 belongs is set to a predetermined network type such as a low-latency network. The predetermined network type is a network type that controls parameters used in data communication between the access point 10 and the terminal 20 depending on whether the terminal 20 is a control target. The terminal 20 sets the network type that it will control. If the network type of the BSS to which the access point 10 belongs matches the network type of the terminal 20 that is a control target, parameters according to the network type of the BSS to which the access point 10 belongs are used in data communication between the access point 10 and the terminal 20.

[0097] In the above configuration, a terminal 20 set as a control target in a predetermined network type performs data communication using parameters different from the parameters used for data communication by terminals 20 that are not control targets. That is, the above configuration makes it possible to control the parameters used for data communication depending on whether or not the terminal 20 is a control target in a predetermined network type. For example, parameters according to the network type of the BSS to which the access point 10 belongs are set to more advantageous parameters than parameters applied to terminals that are not control targets in the network type. This allows terminals 20 set as control targets in a predetermined network type to perform data communication preferentially. As a result, it is possible to suppress deterioration in the communication quality of terminals 20 set as control targets in a predetermined network type.

[0098] The terminal 20 may use the wireless communication unit 140 to notify the access point 10 whether or not the terminal 20 is a control target in the network type to which the access point 10 belongs. According to this configuration, it becomes possible to determine whether or not the terminal 20 is a control target by a handshake between the access point 10 and the terminal 20.

[0099] The present invention is not limited to the above-described embodiments, and various modifications can be made in the implementation stage without departing from the spirit of the invention. Furthermore, the embodiments may be implemented in appropriate combinations, in which case the combined effects can be obtained. Furthermore, the above-described embodiments include various inventions, and various inventions can be extracted by combining selected components from the disclosed components. For example, if the problem can be solved and the effects can be obtained even if some components are removed from all the components shown in the embodiments, the configuration from which these components are removed can be extracted as an invention.

[0100] DESCRIPTION OF SYMBOLS 10...Access point 11...CPU 12...ROM 13...RAM 14...Wireless communication module 15...Wired communication module 20...Terminal 21...CPU 22...ROM 23...RAM 24...Wireless communication module 25...Storage device 40...Wireless network 110...Upper layer processing unit 120...LLC processing unit 130...MAC processing unit 140...Wireless communication unit 150...Management unit 151...Setting unit 152...Beacon transmission unit 153...Connection control unit 154...Communication control unit 210...Upper layer processing unit 220...LLC processing unit 230...MAC processing unit 240...Wireless communication unit 250...Management unit 251...Setting unit 252...Beacon reception unit 253...Connection control unit 254...Communication control unit

Claims

1. An access point comprising: a wireless communication unit configured to communicate wirelessly with a terminal device; a notification unit that notifies, via the wireless communication unit, the network type of a BSS (basic service set) to which the access point belongs; and a communication control unit that controls the wireless communication unit so as to perform data communication with the terminal device using a first parameter corresponding to the network type when the terminal device is subject to control based on the network type.

2. The access point according to claim 1, further comprising a connection control unit that notifies the terminal device of the first parameter via the wireless communication unit in response to the terminal device being subject to control in the network type.

3. The access point according to claim 1, wherein the first parameter is a parameter that is more advantageous than a second parameter that is applied to a terminal device that is not a control target in the network type.

4. The access point of claim 3, wherein the first parameters include at least one of CWmin set to a first value, CWmax set to a second value, TXOPLimit set to a third value, and a preamble detection threshold set to a fourth value; and the second parameters include at least one of CWmin set to a fifth value greater than the first value, CWmax set to a sixth value greater than the second value, TXOPLimit set to a seventh value less than the third value, and a preamble detection threshold set to an eighth value less than the fourth value.

5. The access point according to claim 1, wherein the communication control unit controls the wireless communication unit to perform data communication with the terminal device using the first parameter and a predetermined function when the terminal device is subject to control in accordance with the network type, and the predetermined function is prohibited from being used by terminal devices that are not subject to control in accordance with the network type.

6. A terminal device comprising: a wireless communication unit configured to communicate wirelessly with an access point; a setting unit that sets a first network type that is a network type to be controlled; a network type information acquisition unit that acquires, from the access point, network type information indicating a second network type that is the network type of a BSS (basic service set) to which the access point belongs; and a communication control unit that controls the wireless communication unit to perform data communication with the access point using parameters corresponding to the second network type when the second network type matches the first network type.

7. The terminal device according to claim 6, further comprising a notification unit that notifies the access point via the wireless communication unit whether or not the terminal device is a control target in the second network type.

8. The terminal device according to claim 6, further comprising a connection control unit that acquires information indicating the parameters from the access point via the wireless communication unit.

Images