Terminal and access point

Abstract

This terminal is provided with an authentication information holding unit and a wireless signal processing unit. The authentication information holding unit holds authentication information relating to authentication of a use region with respect to a spectrum mask when preamble puncturing is used. The wireless signal processing unit transmits authentication information relating to the use region of the terminal to an access point.

Description

Terminals and access points

[0001] The embodiments relate to a terminal and an access point.

[0002] A wireless LAN (Local Area Network) is known as a system that wirelessly connects an access point (AP) and a terminal (STA). A wireless LAN allows a terminal located within the communication area of ​​the AP to access a network via the AP.

[0003] The IEEE 802.11ax standard adds a provision called preamble puncturing. Preamble puncturing is a method of specifying in advance, in 20 MHz increments, channel blocks that are expected not to be used for communication due to interference, etc., and performing communication using channel bonding on the premise that the specified 20 MHz channel blocks will not be used. By using preamble puncturing, when narrowband interference is present, it becomes possible to flexibly avoid this and achieve data transmission with the widest possible bandwidth. While preamble puncturing is an optional provision in the IEEE 802.11ax standard, it is expected that preamble puncturing will become a mandatory provision in the next wireless LAN standard, the IEEE 802.11be standard.

[0004] By utilizing preamble puncturing, it is possible to avoid narrowband interference. Therefore, preamble puncturing is expected to be used to avoid interference with existing systems, such as weather radar and mobile radar in the 5 GHz band, and fixed microwave communication systems in the 6 GHz band when database-referenced spectrum sharing is implemented, which has been institutionalized in the United States and is expected to be institutionalized in Japan in the future. In other words, by applying preamble puncturing to avoid using channels that cannot be used by existing systems and by bonding the remaining discontinuous bands for communication, it is expected that channel utilization efficiency will be improved compared to conventional systems.

[0005] However, while current Japanese laws and regulations permit the use of preamble puncturing to avoid interference between wireless LAN systems, they do not permit the use of preamble puncturing to prevent interference with channels used by existing systems when such systems are in operation.

[0006] On the other hand, in the United States, the upper limit of the spectrum mask when preamble puncturing is used is set as a technical condition, and when obtaining equipment certification, the performance of the equipment's spectrum mask is confirmed, and if it is guaranteed that preamble puncturing will not cause interference on channels operated by existing systems, preamble puncturing can be used to avoid interference with existing systems.

[0007] In Japan, there are calls to follow the US approach and revise the system to define the conditions for shared spectrum masks, check the performance of the equipment's spectrum mask when obtaining equipment certification, and allow preamble puncturing to be used to avoid interference with existing systems if the performance of the equipment's spectrum mask is guaranteed to meet the conditions. In response to this request, a working group under the Information and Communications Council is currently discussing this. In Europe, too, discussions are underway to specify the spectrum mask for preamble puncturing.

[0008] "Technical Conditions for the Introduction of Broadband Wireless LAN" and "Technical Conditions for the Advanced Use of Wireless LAN Systems" - Partial Report from the Information and Communications Council - September 12, 2023, Ministry of Internal Affairs and Communications Press Release, [Online], accessed August 19, 2024, Internet <URL https: / / www.soumu.go.jp / menu_news / s-news / 01kiban12_02000153.html> Pelin Salem, et. al., "LPI Static Preamble Puncturing" doc.: IEEE 802.11-24 / 0534r2, April 2024., [Online], accessed August 19, 2024, Internet <URL "Frequency Sharing Using Preamble Puncturing," Ministry of Internal Affairs and Communications, Information Technology Subcommittee, Land Radio Communications Committee, 5.2 GHz and 6 GHz Band Wireless LAN Working Group (12th Meeting) (held July 22, 2024), [Online], accessed August 19, 2024, Internet. URL: https: / / www.soumu.go.jp / main_sosiki / joho_tsusin / policyreports / joho_tsusin / rikujou / 02kiban12_04000388.html

[0009] If future amendments to laws and regulations allow the use of preamble puncturing to avoid interference with existing systems only for devices that guarantee spectrum mask performance, it is expected that devices that have obtained certification to ensure that they can use preamble puncturing to avoid interference with existing systems will coexist with devices that have not. From the perspective of protecting existing systems, it is important to allow certified devices to use preamble puncturing for the purpose of avoiding interference with existing systems, and not to allow this for uncertified devices.

[0010] The embodiments provide a terminal and an access point for appropriately operating preamble puncturing for the purpose of avoiding interference with existing systems.

[0011] A terminal according to one aspect includes an authentication information storage unit and a radio signal processing unit. The authentication information storage unit stores authentication information related to authentication of a region of use regarding a spectrum mask when preamble puncturing is used. The radio signal processing unit transmits the authentication information of the region of use of the terminal to an access point.

[0012] According to the embodiment, a terminal and an access point are provided for appropriately operating preamble puncturing for the purpose of avoiding interference with existing systems.

[0013] FIG. 1 is a block diagram showing an example of the configuration of a communication system according to an embodiment. FIG. 2 is a block diagram showing an example of the hardware configuration of an AP. FIG. 3 is a block diagram showing an example of the hardware configuration of a terminal. FIG. 4 is a block diagram showing an example of the functional configuration of an AP according to an embodiment. FIG. 5 is a block diagram showing an example of the functional configuration of a terminal according to an embodiment. FIG. 6 is a flowchart showing the operation of an AP in a communication system. FIG. 7 is a diagram showing an example of the allocation of 160 MHz channels. FIG. 8 is a diagram showing an example of an interference situation identified by interference information from a terminal according to an embodiment. FIG. 9 is a diagram showing a puncturing pattern derived for a terminal that has not obtained authentication ensuring that it can be used to avoid interference with an existing system. FIG. 10 is a diagram showing a puncturing pattern derived for a terminal that has obtained authentication ensuring that it can be used to avoid interference with an existing system. FIG. 11A is a diagram showing an example of the frame format of a notification frame for notifying a puncturing pattern. FIG. 11B is a diagram showing an example of the frame format of a notification frame for notifying a puncturing pattern. FIG. 12 is a flowchart showing the operation of a terminal in a communication system. FIG. 13 is a diagram showing an example of an interference situation identified by interference information from a terminal according to a modified example. Fig. 14 is a diagram showing a puncturing pattern derived for terminal 20-1 in the modified example, and Fig. 15 is a diagram showing a puncturing pattern derived for terminal 20-N in the modified example.

[0014] Hereinafter, an embodiment will be described with reference to the drawings. Fig. 1 is a block diagram showing an example of the configuration of a communication system according to an embodiment. As shown in Fig. 1, the communication system 1 is a wireless LAN system including an access point (AP) 10 and terminals (STAs) 20-1, 20-2, ..., 20-N. The AP 10 can be further connected to a network 30.

[0015] The AP 10 and the terminals 20-1, 20-2, ..., 20-N have wireless communication functions based on, for example, the OSI (Open Systems Interconnection) reference model. In the OSI reference model, wireless communication functions are divided 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). The data link layer includes a Logical Link Control (LLC) sublayer and a Medium Access Control (MAC) sublayer.

[0016] The AP 10 and terminals 20-1, 20-2, ..., 20-N support preamble puncturing. The AP 10 and terminals 20-1, 20-2, ..., 20-N may apply preamble puncturing to avoid interference between wireless LAN systems. Furthermore, at least some of the AP 10 and terminals 20-1, 20-2, ..., 20-N may apply preamble puncturing to avoid interference with existing systems. Existing systems are systems that do not constitute a wireless LAN system together with the AP or terminals, such as weather radar and mobile radar in the 5 GHz band, and fixed microcommunication systems, broadcasting systems, and radio astronomy systems when performing database-reference frequency sharing in the 6 GHz band. Preamble puncturing will be explained in detail later.

[0017] Terminals 20-1, 20-2, ..., 20-N are terminals that operate as N STAs (stations) 1, 2, ..., N. N is a natural number. Terminals 20-1, 20-2, ..., 20-N can exchange traffic with AP 10. Terminals 20-1, 20-2, ..., 20-N are, for example, smartphones or PCs (personal computers), and are wireless terminals that comply with the IEEE 802.11 standard. In the following, terminals 20-1, 20-2, ..., 20-N have the same configuration. In the following, when there is no particular need to distinguish between terminals 20-1, 20-2, ..., 20-N, they may be referred to as terminal 20.

[0018] Next, the hardware configuration of the AP and the terminal in the communication system according to the embodiment will be described.

[0019] 2 is a block diagram showing an example of the hardware configuration of an AP 10. As shown in FIG. 2, the AP 10 includes, for example, a central processing unit (CPU) 11, a read only memory (ROM) 12, a random access memory (RAM) 13, a wireless communication module 14, and a wired communication module 15.

[0020] The CPU 11 is a processing circuit that controls the overall operation of the AP 10. The ROM 12 is, for example, a non-volatile semiconductor memory. The ROM 12 stores programs and data for controlling the AP 10. The RAM 13 is, for example, a volatile semiconductor memory. The RAM 13 is used as a work area for the CPU 11. The wireless communication module 14 is a circuit used to send and receive data via wireless signals. The wireless communication module 14 is connected to an antenna. The wired communication module 15 is a circuit used to send and receive data via wired signals. The wired communication module 15 is connected to the network 30.

[0021] Although the wired communication module 15 is described as a means for connecting the AP 10 to the network 30, alternatively, a wireless communication module different from the wireless communication module 14 may be used to connect the AP 10 to the network 30, or the wireless communication module 14 may communicate with the network 30 during times when it is not communicating with the terminal 20.

[0022] 3 is a block diagram showing an example of the hardware configuration of the terminal 20. As shown in FIG. 3, the terminal 20 includes, for example, a CPU 21, a ROM 22, a RAM 23, a wireless communication module 24, a display 25, and a storage 26.

[0023] The CPU 21 is a processing circuit that controls the overall operation of the terminal 20. The ROM 22 is, for example, a non-volatile semiconductor memory. The ROM 22 stores programs and data for controlling the terminal 20. The RAM 23 is, for example, a volatile semiconductor memory. The RAM 23 is used as a working area for the CPU 21. The wireless communication module 24 is a circuit used for transmitting and receiving data via wireless signals. The wireless communication module 24 is connected to an antenna. The display 25 is, for example, an LCD (liquid crystal display) or an EL (electro-luminescence) display. The display 25 displays a GUI (graphical user interface) corresponding to application software, etc. The storage 26 is a non-volatile storage device. The storage 26 stores system software, etc. of the terminal 20.

[0024] Next, the functional configuration of the AP and the terminal in the communication system according to the embodiment will be described.

[0025] 4 is a block diagram showing an example of the functional configuration of an AP according to an embodiment. The AP 10 functions as a computer including a data processing unit 110, a frame processing unit 120, a management unit 130, and a radio signal processing unit 140. The data processing unit 110 is a functional block that executes processing corresponding to the LLC sublayer of layer 2 and layers 3 to 7. The frame processing unit 120 and the management unit 130 are functional blocks that execute processing corresponding to the MAC sublayer of layer 2. The radio signal processing unit 140 is a functional block that executes processing corresponding to layer 1.

[0026] The data processing unit 110 outputs data input from the network 30 via the LLC layer to the frame processing unit 120. The data processing unit 110 also outputs data input from the frame processing unit 120 to the network 30 via the LLC layer.

[0027] When data is input to frame processing unit 120 from data processing unit 110 or management unit 130, frame processing unit 120 adds a MAC header to the input data to generate a MAC frame. Frame processing unit 120 then outputs the MAC frame to radio signal processing unit 140. When a MAC frame is input from radio signal processing unit 140, frame processing unit 120 extracts data from the MAC frame and outputs the extracted data to data processing unit 110 or management unit 130 depending on the type of MAC frame. Specifically, when the MAC frame is a data frame, frame processing unit 120 inputs the data to data processing unit 110. When the MAC frame is a management frame or a control frame, frame processing unit 120 inputs the data to management unit 130.

[0028] The management unit 130 controls a logical wireless connection between the AP 10 and the terminal 20. For example, the management unit 130 executes wireless connection processing in response to an association request from the terminal 20. The management unit 130 also includes an interference information storage unit 131, an authentication information storage unit 132, and a puncturing pattern derivation unit 133.

[0029] The interference information storage unit 131 stores interference information related to interference experienced by the communication system 1. The interference includes interference with a wireless LAN system other than the communication system 1. Furthermore, the interference includes interference with an existing system that exists within or outside the coverage area of ​​the AP 10. The interference information includes information on the channel on which interference is occurring and information indicating whether the device on which interference is occurring is an existing system. The interference information can be collected, for example, by a receiving operation during a time period when the AP 10 itself is not communicating or by a report from a terminal 20 subordinate to the AP 10.

[0030] The authentication information storage unit 132 stores authentication information for the AP 10 itself and each of the terminals 20 subordinate to it. In the embodiment, the authentication information includes authentication information related to preamble puncturing. The authentication information related to preamble puncturing includes usage area information indicating whether the AP 10 has been certified to ensure that preamble puncturing is available for the purpose of avoiding interference with existing systems in the country or region in which the AP 10 is currently located. The certification to ensure that preamble puncturing is available for the purpose of avoiding interference with existing systems includes certification related to the performance of the spectral mask. Furthermore, the usage area information is reported to the terminal 20, for example, by the AP 10 using a country element defined in the IEEE 802.11-2020 standard, and the terminal 20 thereby recognizes the country in which it is operating. Furthermore, the authentication information related to preamble puncturing includes information for each terminal 20 indicating whether the terminal 20 has been certified to ensure that preamble puncturing is available for the purpose of avoiding interference with existing systems in the country or region in which the terminal 20 is currently located. The authentication information in the embodiment may include authentication information other than authentication information related to preamble puncturing. The authentication information may be notified from the terminal 20 under the control of the AP 10. The authentication information may be notified by being included in an association request, a probe request, or the like from the terminal 20. Here, the authentication information may be notified from the terminal 20 by extending a reserved area of ​​the HE PHY Capabilities subfield in the HE Operation element defined in the IEEE 802.11-2020 standard, for example. The HE PHY Capabilities subfield is a subfield for notifying the capabilities of the terminal. Alternatively, the authentication information may be notified by extending another existing reserved area or by defining a new field.

[0031] The puncturing pattern derivation unit 133 derives a puncturing pattern based on the interference information stored in the interference information storage unit 131 and the authentication information reported from the subordinate terminals 20 stored in the authentication information storage unit 132. The puncturing pattern is a pattern indicating which channel blocks are not to be used for channel bonding during wireless communication. When there are channel blocks that are subject to interference from other wireless LAN systems, the puncturing pattern derivation unit 133 derives a puncturing pattern that specifies channel blocks to be bonded so as not to use the channel blocks that are subject to interference from the other wireless LAN systems. Furthermore, when there are channel blocks that are subject to interference from an existing system, the puncturing pattern derivation unit 133 derives a puncturing pattern that specifies channel blocks to be bonded so as not to use the channel blocks that are subject to interference from the existing system, only for terminals that are authenticated as being able to use preamble puncturing for the purpose of avoiding interference with the existing system. On the other hand, even if there is a channel block that is experiencing interference from an existing system, the puncturing pattern derivation unit 133 does not use preamble puncturing for the purpose of avoiding interference from the existing system for a terminal that has not been certified to be able to use preamble puncturing for the purpose of avoiding interference with the existing system.

[0032] The radio signal processing unit 140 performs processing for transmitting and receiving radio signals and includes a modulation unit 141, a demodulation unit 142, and a time division duplex (TDD) switch 143.

[0033] The modulation unit 141 generates a radio frame by adding a preamble and the like to the MAC frame input from the frame processing unit 120. The modulation unit 141 converts the generated radio frame into a radio signal. The modulation unit 141 then outputs the converted radio signal to an antenna via the TDD switch 143. The conversion process from the radio frame to the radio signal includes, for example, error correction coding, interleaving, subcarrier modulation, inverse fast Fourier transform, OFDM modulation, and frequency conversion.

[0034] The demodulator 142 converts the radio signal received from the antenna via the TDD switch 143 into a radio frame. The demodulator 142 extracts a MAC frame from the converted radio frame. The demodulator 142 then outputs the extracted MAC frame to the frame processor 120. The conversion process from the radio signal to the radio frame includes, for example, frequency conversion, OFDM demodulation, fast Fourier transform, subcarrier demodulation, deinterleaving, and error correction decoding.

[0035] The TDD switch 143 switches the connection between the modulation unit 141 and the antenna and the connection between the demodulation unit 142 and the antenna in a time-division manner. When the modulation unit 141 and the antenna are connected by the TDD switch 143, the radio signal output from the modulation unit 141 is transmitted from the antenna. When the demodulation unit 142 and the antenna are connected by the TDD switch 143, the radio signal received by the antenna is sent to the demodulation unit 142.

[0036] 5 is a block diagram showing an example of the functional configuration of a terminal according to an embodiment. The terminal 20 functions as a computer including a data processing unit 210, a frame processing unit 220, a management unit 230, a radio signal processing unit 240, and an application execution unit 250. The data processing unit 210 and the application execution unit 250 are functional blocks that execute processes corresponding to the LLC sublayer of layer 2 and layers 3 to 7. The frame processing unit 220 and the management unit 230 are functional blocks that execute processes corresponding to the MAC sublayer of layer 2. The radio signal processing unit 240 is a functional block that executes processes corresponding to layer 1.

[0037] The data processing unit 210 outputs data input from the application execution unit 250 via the LLC layer to the frame processing unit 220. The data processing unit 210 also outputs data input from the frame processing unit 220 to the application execution unit 250 via the LLC layer.

[0038] When data is input to frame processing unit 220 from data processing unit 210 or management unit 230, frame processing unit 220 adds a MAC header to the input data to generate a MAC frame. Frame processing unit 220 then outputs the MAC frame to radio signal processing unit 240. When a MAC frame is input from radio signal processing unit 240, frame processing unit 220 extracts data from the MAC frame and outputs the extracted data to data processing unit 210 or management unit 230 depending on the type of MAC frame. Specifically, when the MAC frame is a data frame, frame processing unit 220 inputs the data to data processing unit 210. When the MAC frame is a management frame or a control frame, frame processing unit 220 inputs the data to management unit 230.

[0039] The management unit 230 controls the logical wireless connection between the terminal 20 and the AP 10. For example, the management unit 230 generates an association request based on a beacon frame from the AP 10. The management unit 230 also includes an authentication information holding unit 231.

[0040] The authentication information storage unit 231 stores authentication information received at the time of manufacturing the terminal 20, etc. The authentication information in the embodiment includes authentication information related to preamble puncturing. The authentication information related to preamble puncturing includes information indicating whether or not authentication has been obtained for each country or region to allow use of preamble puncturing for the purpose of avoiding interference with existing systems. The authentication information may further include other information. Furthermore, the authentication information may be in a format that notifies whether or not authentication has been obtained for each frequency band, such as the 2.4 GHz band, the 5 GHz band, or the 6 GHz band, or for each frequency band for which authentication is obtained, which is more specifically, for each individual frequency range.

[0041] The radio signal processing unit 240 performs processing for transmitting and receiving radio signals and includes a modulation unit 241, a demodulation unit 242, and a time division duplex (TDD) switch 243.

[0042] The modulation unit 241 generates a radio frame by adding a preamble and the like to the MAC frame input from the frame processing unit 220. The modulation unit 241 converts the generated radio frame into a radio signal. The modulation unit 241 then outputs the converted radio signal to an antenna via the TDD switch 243. The conversion process from the radio frame to the radio signal includes, for example, error correction coding, interleaving, subcarrier modulation, inverse fast Fourier transform, OFDM modulation, and frequency conversion.

[0043] The demodulator 242 converts the radio signal received from the antenna via the TDD switch 243 into a radio frame. The demodulator 242 extracts a MAC frame from the converted radio frame. The demodulator 242 then outputs the extracted MAC frame to the frame processor 220. The conversion process from the radio signal to the radio frame includes, for example, frequency conversion, OFDM demodulation, fast Fourier transform, subcarrier demodulation, deinterleaving, and error correction decoding.

[0044] The TDD switch 243 switches the connection between the modulation unit 241 and the antenna and the connection between the demodulation unit 242 and the antenna in a time-division manner. When the modulation unit 241 and the antenna are connected by the TDD switch 243, the radio signal output from the modulation unit 241 is transmitted from the antenna. When the demodulation unit 242 and the antenna are connected by the TDD switch 243, the radio signal received by the antenna is sent to the demodulation unit 242.

[0045] The application execution unit 250 executes an application based on data input from the data processing unit 210. The application execution unit 250 also inputs data to the data processing unit 210. For example, the application execution unit 250 can display application information on the display 25. The application execution unit 250 can also operate based on operations on an input interface.

[0046] Next, the operation of preamble puncturing in the communication system according to the embodiment will be described. FIG. 6 is a flowchart showing the operation of the AP 10 in the communication system 1. Here, in FIG. 6, it is assumed that the AP 10 has been certified for its spectral mask performance in the country or region where the AP 10 is installed, so that preamble puncturing can be used to avoid interference with existing systems. In this example, the AP 10 and the terminal 20 are capable of communication on a 160 MHz channel. Meanwhile, the IEEE 802.11be standard is expected to enable communication on a 320 MHz channel. In the embodiment, the AP 10 and the terminal 20 may be configured to be capable of communication on an 80 MHz or 320 MHz channel.

[0047] In step S11, the AP 10 acquires authentication information of each of the subordinate terminals 20. Then, the AP 10 stores the acquired authentication information in the authentication information storage unit 132. The AP 10 may request the subordinate terminals 20 to transmit the authentication information. The authentication information may be included in an association request, a probe request, or the like transmitted from the terminals 20.

[0048] In step S12, the AP 10 acquires interference information within its coverage area. Then, the AP 10 stores the acquired interference information in the interference information storage unit 131. The interference information may be collected, for example, from subordinate terminals 20. The AP 10 may periodically request subordinate terminals 20 to report interference information, or may periodically receive reports of interference information from subordinate terminals 20 without requesting a report. Alternatively, reports may be received from wireless devices or systems other than the AP 10 and the terminals 20.

[0049] In step S13, the AP 10 determines whether interference is expected during communication based on the interference information stored in the interference information storage unit 131. If it is determined in step S13 that interference is expected, the process proceeds to step S14. If it is determined in step S13 that interference is not expected, the process proceeds to step S19.

[0050] In step S14, the AP 10 determines whether or not the expected interference includes interference from the existing system based on the interference information stored in the interference information storage unit 131. If it is determined in step S14 that the expected interference includes interference from the existing system, the process proceeds to step S15. If it is determined in step S14 that the expected interference does not include interference from the existing system, the process proceeds to step S17.

[0051] In step S15, the AP 10 derives a puncturing pattern for each of the subordinate terminals 20. At this time, the AP 10 derives different puncturing patterns for terminals that have acquired authentication that ensures that preamble puncturing can be used to avoid interference with existing systems and terminals that have not. Details of the derivation of puncturing patterns will be described later.

[0052] In step S16, the AP 10 notifies each of the subordinate terminals 20 of the derived puncturing pattern. Thereafter, the process proceeds to step S19. The AP 10 expresses the puncturing pattern using bitmap information defined in the Bandwidth Indication Parameters field, which is one of the fields constituting the EHT Operation element defined in, for example, IEEE 802.11be draft D7.0 (IEEE P802.11be / D7.0, IEEE Standards Activities Department, August 2024), and includes this in a beacon to notify each of the terminals 20. The notification of the puncturing pattern may be included in a management frame or control frame other than a beacon and notified to all terminals or individually to each terminal. Alternatively, the information may be notified for each frame in the header of the data frame, for example, in the Bandwidth field in the HE-SIG-A of IEEE 802.11ax or the Punctured Channel Information field in the U-SIG of IEEE 802.11be.

[0053] In step S17, the AP 10 derives a uniform puncturing pattern for the terminals 20 under its control.

[0054] In step S18, the AP 10 notifies each of the subordinate terminals 20 of the derived puncturing pattern. After that, the process proceeds to step S19. The AP 10 notifies each of the terminals 20 of the puncturing pattern, for example, by including the puncturing pattern in a beacon. The puncturing pattern may be notified by being included in a management frame or a control frame other than a beacon.

[0055] In step S19, the AP 10 determines whether or not to perform communication. For example, the AP 10 determines to perform communication when traffic to be transmitted occurs in the AP 10 or when a request to transmit traffic is received from the terminal 20. If it is determined in step S19 that communication is to be performed, the process proceeds to step S20. If it is determined in step S19 that communication is not to be performed, the process returns to step S11.

[0056] In step S20, the AP 10 communicates with the terminal 20. After the communication, the process returns to step S11. Here, when communicating with the terminal 20 for which a puncturing pattern has been notified, the AP 10 communicates according to the notified puncturing pattern. Specifically, the AP 10 communicates by using a spectrum mask that does not use blocks of 20 MHz channels that are specified not to be used for communication in the puncturing pattern.

[0057] The derivation of puncturing patterns in the embodiment will be described below. Figure 7 is a diagram showing an example of the arrangement of 160 MHz channels. The channel blocks constituting the 160 MHz channel are a primary 20 MHz channel, a secondary 20 MHz channel, a secondary 40 MHz channel, and a secondary 80 MHz channel. The primary 20 MHz channel is a block of 20 MHz channels that is always used during communication. The secondary 20 MHz channel is a block of 20 MHz channels adjacent to the primary 20 MHz channel. The secondary 40 MHz channel is a block of 40 MHz channels adjacent to the primary 40 MHz channel. The secondary 80 MHz channel is a block of 80 MHz channels adjacent to the primary 80 MHz channel.

[0058] Here, the use of the 80 MHz channel, 40 MHz channel, and 20 MHz channel is limited to the use of consecutive channels including the primary 20 MHz channel. In other words, the use of the 80 MHz channel is limited to the simultaneous use of the primary 20 MHz channel, the secondary 20 MHz channel, and the secondary 40 MHz channel. Similarly, the use of the 40 MHz channel is limited to the simultaneous use of the primary 20 MHz channel and the secondary 20 MHz channel. Furthermore, the use of the 20 MHz channel is limited to the use of the primary 20 MHz channel. According to these bonding channel rules, for example, if the carrier sense result for the secondary 20 MHz is busy and the carrier sense results for all other blocks are idle, only the block for the primary 20 MHz channel can be used. In other words, due to the channel usage restrictions, wireless channels may not be used efficiently depending on the carrier sense results.

[0059] In contrast, with preamble puncturing, a 20 MHz channel that is not expected to be used for communication is designated in advance, and communication is performed on the assumption that this channel will not be used. The 20 MHz channel that is not expected to be used for communication is a channel that is expected to be subject to interference from other wireless LAN systems and to interference from an existing system. In the embodiment, when an existing system is in operation, a puncturing pattern that aims to avoid interference with the existing system in addition to avoiding interference with other wireless LAN systems is set for a terminal that has obtained certification that ensures that preamble puncturing can be used to avoid interference with the existing system, and a puncturing pattern that aims only to avoid interference with other wireless LAN systems is set for a terminal that has not obtained certification.

[0060] 8 is a diagram showing an example of an interference situation identified by interference information from terminal 20. In this example, interference I1 with another wireless LAN system is detected in a channel block of the 20 MHz-40 MHz band of the secondary 40 MHz channel, and interference R with an existing system such as weather radar is detected in a channel block of the 80 MHz-100 MHz band of the secondary 80 MHz channel.

[0061] FIG. 9 is a diagram showing puncturing patterns derived for a terminal that has not obtained authentication ensuring that preamble puncturing can be used to avoid interference with existing systems. Here, the process of deriving a uniform puncturing pattern in step S17 assumes that there is no interference with existing systems. Therefore, in step S17, the puncturing pattern may be derived based on the same concept as in FIG. 9 . A terminal that has not obtained authentication ensuring that preamble puncturing can be used to avoid interference with existing systems can only use preamble puncturing intended for avoiding interference with other wireless LAN systems. Therefore, the puncturing pattern derivation unit 133 derives a puncturing pattern that specifies not to use the 20 MHz-40 MHz channel block of the secondary 40 MHz channel to avoid interference with other wireless LAN systems. According to the channel bonding rules, if carrier sensing detects that the 20 MHz-40 MHz channel block of the secondary 40 MHz channel is busy, only the primary 20 MHz channel and the secondary 20 MHz channel will be available for communication. In contrast, by specifying in advance not to use the 20 MHz-40 MHz band channel block of the secondary 40 MHz channel, carrier sensing is not performed for the 20 MHz-40 MHz band channel block of the secondary 40 MHz channel. Furthermore, transmission power control is performed to prevent transmissions from being performed on this channel block. This allows the 0 MHz-20 MHz band of the secondary 40 MHz channel to be used for communication in addition to the primary 20 MHz channel and secondary 20 MHz channel.

[0062] On the other hand, since no certification has been obtained to ensure that the secondary 80 MHz channel can be used to avoid interference with existing systems, if carrier sensing detects that the 80 MHz-100 MHz band channel block of the secondary 80 MHz channel is busy, the secondary 80 MHz channel cannot be used for communication.

[0063] FIG. 10 is a diagram showing puncturing patterns derived for a terminal that has obtained authentication ensuring that it can be used to avoid interference with existing systems. A terminal that has obtained authentication ensuring that it can be used to avoid interference with existing systems can use preamble puncturing for the purpose of avoiding interference with existing systems in addition to preamble puncturing for the purpose of avoiding interference with other wireless LAN systems. Therefore, the puncturing pattern derivation unit 133 derives a puncturing pattern that specifies not to use the 20 MHz-40 MHz band channel block of the secondary 40 MHz channel to avoid interference with other wireless LAN systems, and also specifies not to use the 80 MHz-100 MHz band channel block of the secondary 80 MHz channel to avoid interference with existing systems. As a result, carrier sensing is not performed for the 20 MHz-40 MHz band channel block of the secondary 40 MHz channel and the 80 MHz-100 MHz band channel block of the secondary 80 MHz channel. Furthermore, transmission power control is performed to prevent transmissions from occurring on these channel blocks. This allows the 0 MHz-20 MHz band of the secondary 40 MHz channel and the 100 MHz-160 MHz band of the secondary 80 MHz channel to be used for communication in addition to the primary 20 MHz channel and the secondary 20 MHz channel.

[0064] 11A and 11B are diagrams showing an example of a frame format of a notification frame for notifying a puncturing pattern.

[0065] 11A shows a frame format when a puncturing pattern is simultaneously broadcast to each terminal 20. The puncturing pattern broadcast frame of the example shown in FIG. 11A has a field for storing a puncturing pattern for authenticated devices and a field for storing a puncturing pattern for unauthenticated devices. The puncturing pattern for authenticated devices is, for example, a puncturing pattern for terminals that have obtained certification to ensure that it can be used to avoid interference with existing systems, as shown in FIG. 10. The puncturing pattern for unauthenticated devices is, for example, a puncturing pattern for terminals that have not obtained certification to ensure that it can be used to avoid interference with existing systems, as shown in FIG. 9. The field for storing the puncturing pattern may be, for example, the Punctured Channel Information field of the U-SIG field. Of course, the field for storing the puncturing pattern may be other than the Punctured Channel Information field of the U-SIG field, for example, the Disabled Subchannel Bitmap Present field of the EHT Operation element.

[0066] 11A is broadcast as, for example, a beacon frame to terminals 20 under the AP 10. When receiving the notification frame shown in Fig. 11A, if the terminal 20 is an authenticated device, it extracts a puncturing pattern for authenticated devices, and if the terminal 20 is not an authenticated device, it extracts a puncturing pattern for non-authenticated devices.

[0067] 11B shows a frame format when a puncturing pattern is broadcast individually to each terminal 20. The puncturing pattern broadcast frame of the example shown in FIG. 11B is divided into a broadcast frame for broadcasting a puncturing pattern for authenticated devices and a broadcast frame for broadcasting a puncturing pattern for unauthenticated devices. The broadcast frame for broadcasting a puncturing pattern for authenticated devices has a field for storing the puncturing pattern for authenticated devices. The broadcast frame for broadcasting a puncturing pattern for unauthenticated devices has a field for storing the puncturing pattern for unauthenticated devices. For example, the Punctured Channel Information field of the U-SIG field can be used as the field for storing the puncturing pattern. Of course, other than the Punctured Channel Information field of the U-SIG field, for example, the Disabled Subchannel Bitmap Present field of the EHT Operation element or an extended field thereof may be used as the field for storing the puncturing pattern.

[0068] The notification frame shown in Fig. 11B is transmitted individually to terminals 20 under the AP 10 as, for example, an action frame. That is, a notification frame for notifying a puncturing pattern for authenticated devices is transmitted to authenticated terminals 20, and a notification frame for notifying a puncturing pattern for non-authenticated devices is transmitted to non-authenticated terminals 20. The notification frame for notifying a puncturing pattern for authenticated devices may be transmitted to multiple users addressed to multiple authenticated terminals 20. Similarly, the notification frame for notifying a puncturing pattern for non-authenticated devices may be transmitted to multiple users addressed to multiple non-authenticated terminals 20. The terminal 20 receiving the notification frame shown in Fig. 11B extracts the puncturing pattern from the notification frame.

[0069] 12 is a flowchart showing the operation of the terminal 20 in the communication system 1. In step S101, the terminal 20 determines whether or not to transmit authentication information. The terminal 20 determines that the authentication information will be transmitted when there is a request from the AP 10, when a communication request is made to the AP 10, or the like. If it is determined in step S101 that the authentication information will be transmitted, the process proceeds to step S102. If it is determined in step S102 that the authentication information will not be transmitted, the process proceeds to step S103.

[0070] In step S102, the terminal 20 transmits authentication information for the country or region in which the terminal 20 is currently located to the AP 10. As described above, the terminal 20 may notify the authentication information by extending the reserved area of ​​the HE PHY Capability subfield in the HE Operation element.

[0071] In step S103, the terminal 20 determines whether to report interference information. If there is a request from the AP 10, it is determined that the interference authentication information will be reported at predetermined intervals, etc. If it is determined in step S103 that the interference information will be reported, the process proceeds to step S104. If it is determined in step S103 that the interference information will not be reported, the process proceeds to step S105.

[0072] In step S104, the terminal 20 measures the received power level by performing, for example, a clear channel assessment (CCA) operation, and identifies the channel in which interference is occurring and whether there is interference with the existing system from the received power level.The terminal 20 then reports the channel in which interference is occurring and information on whether there is interference with the existing system to the AP 10 as interference information.The interference information may also be reported by other methods.

[0073] In step S105, the terminal 20 determines whether or not a puncturing pattern notification has been received from the AP 10. If it is determined in step S105 that a puncturing pattern notification has been received, the process proceeds to step S106. If it is determined in step S105 that a puncturing pattern notification has not been received, the process proceeds to step S107.

[0074] In step S106, the terminal 20 stores the puncturing pattern extracted from the notification frame in, for example, the radio signal processing unit 240.

[0075] In step S107, the terminal 20 determines whether or not to perform communication. For example, the terminal 20 determines to perform communication when traffic to be transmitted occurs in the terminal 20 or when the terminal 20 receives a notification of traffic transmission from the AP 10. If it is determined in step S107 that communication will be performed, the process proceeds to step S108. If it is determined in step S107 that communication will not be performed, the process returns to step S101.

[0076] In step S108, the terminal 20 communicates with the AP 10. After the communication, the process returns to step S101. If a puncturing pattern has already been stored, the terminal 20 communicates according to the stored puncturing pattern. Specifically, the terminal 20 communicates using a spectrum mask that does not use blocks of the 20 MHz channel that are specified not to be used for communication in the puncturing pattern.

[0077] As described above, according to the embodiment, the terminal 20 transmits to the AP 10 authentication information indicating whether the terminal 20 has been authenticated to ensure that preamble puncturing can be used to avoid interference with an existing system in the country or region in which the terminal 20 is currently located. When the existing system is in operation, the AP 10 derives a puncturing pattern for avoiding interference with the existing system in addition to avoiding interference with other wireless LAN systems for terminals that have been authenticated to ensure that preamble puncturing can be used to avoid interference with the existing system, and derives a puncturing pattern for avoiding interference only with other wireless LAN systems for terminals that have not been authenticated. The AP 10 then broadcasts the derived puncturing patterns to each terminal 20. The terminals 20 each apply preamble puncturing according to the broadcast puncturing pattern. As a result, even if devices that have obtained certification to ensure that preamble puncturing can be used to avoid interference with existing systems and devices that do not are mixed in communication system 1, only terminal 20 that is guaranteed not to cause interference with the existing system can apply preamble puncturing in a puncturing pattern intended to avoid interference with the existing system. As a result, existing systems are protected from harmful interference, and each terminal can communicate with high channel utilization efficiency.

[0078] (Modification) A modification of the embodiment will be described below. In the embodiment, a different puncturing pattern is derived depending on whether the terminal is a terminal that has been authenticated to ensure that preamble puncturing is available for the purpose of avoiding interference with existing systems. In addition, different puncturing patterns may also be derived for each terminal for preamble puncturing intended to avoid interference with other wireless LAN systems.

[0079] For example, near the boundary of the coverage area of ​​AP 10, each terminal may experience interference from different wireless LAN systems on different channel blocks. In the example shown in FIG. 1 , terminal 20-1 may experience interference from a first wireless LAN system on a first channel block, while terminal 20-N may experience interference from a second wireless LAN system on a second channel. In this case, for the purpose of avoiding interference with the wireless LAN systems, AP 10 may broadcast to both terminal 20-1 and terminal 20-N a puncturing pattern that specifies that neither the first channel block nor the second channel block be used. Meanwhile, in a modified example described below, AP 10 broadcasts to terminal 20-1 a puncturing pattern that specifies that the first channel block be not used, and to terminal 20-N a puncturing pattern that specifies that the second channel block be not used.

[0080] The following describes the modified example in detail. Fig. 13 is a diagram showing an example of an interference situation identified by interference information from terminal 20. In one example, for terminal 20-1, interference I1 with another wireless LAN system is detected in a channel block of the 20 MHz-40 MHz band of the secondary 40 MHz channel. In another example, for terminal 20-N, interference I2 with another wireless LAN system is detected in a channel block of the 100 MHz-120 MHz band of the secondary 80 MHz channel.

[0081] 14 is a diagram showing a puncturing pattern derived for terminal 20-1 in a modified example. In this modified example, the puncturing pattern derivation unit 133 derives a puncturing pattern that specifies that terminal 20-1 does not use channel blocks in the 20 MHz-40 MHz band of the secondary 40 MHz channel, which are channel blocks that are experiencing interference. In other words, the puncturing pattern derivation unit 133 does not specify, for terminal 20-1, that terminal 20-N does not use channel blocks in the 100 MHz-120 MHz band of the secondary 80 MHz channel, which are channel blocks that are experiencing interference.

[0082] 15 is a diagram showing a puncturing pattern derived for terminal 20-N in a modified example. In this modified example, the puncturing pattern derivation unit 133 derives a puncturing pattern that specifies that terminal 20-N not use channel blocks in the 100 MHz-120 MHz band of the secondary 80 MHz channel, which are channel blocks that are experiencing interference. In other words, the puncturing pattern derivation unit 133 does not specify, for the puncturing pattern for terminal 20-N, that not use channel blocks in the 20 MHz-40 MHz band of the secondary 40 MHz channel, which are channel blocks that are experiencing interference for terminal 20-1.

[0083] The AP 10 broadcasts the puncturing pattern derived as shown in Fig. 14 to the terminal 20-1. Similarly, the AP 10 broadcasts the puncturing pattern derived as shown in Fig. 15 to the terminal 20-N. The terminals 20-1 and 20-N apply preamble puncturing in accordance with the respective broadcast puncturing patterns. This can improve channel utilization efficiency in communications between the terminals 20-1 and 20-N.

[0084] Here, it goes without saying that even in the modified example, if the terminal is a terminal that has been certified to ensure that preamble puncturing can be used for the purpose of avoiding interference with existing systems, preamble puncturing can be applied for the purpose of avoiding interference with existing systems.

[0085] (Other Modifications) The processing in the AP 10 and the terminal 20 can be stored as a program that can be executed by a processor, which is a computer. Alternatively, the processing can be stored in a storage medium of an external storage device such as a magnetic disk, optical disk, or semiconductor memory and distributed. The processors of the AP 10 and the terminal 20 can then load the program stored in the storage medium of the external storage device and execute various processes by having their operations controlled by the loaded program.

[0086] 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 elements from the disclosed elements. For example, if the problem can be solved and the desired effect can be obtained even if some elements are deleted from all elements shown in the embodiments, the configuration from which these elements are deleted can be extracted as an invention.

[0087] 1...Communication system 10...Access point (AP) 11...CPU 12...ROM 13...RAM 14...Wireless communication module 15...Wired communication module 20, 20-1, ..., 20-N...Terminal 21...CPU 22...ROM 23...RAM 24...Wireless communication module 25...Display 26...Storage 30...Network 110...Data processing unit 120...Frame processing unit 130...Management unit 131...Interference information storage unit 132...Authentication information storage unit 133...Pattern derivation unit 140...Wireless signal processing unit 141...Modulation unit 142...Demodulation unit 143...Time division duplex (TDD) switch 210...Data processing unit 220...Frame processing unit 230...Management unit 231...Authentication information holding unit 240...Wireless signal processing unit 241...Modulation unit 242...Demodulation unit 243...Time division duplex (TDD) switch 250...Application execution unit

Claims

1. A terminal that has acquired certification for a region of use regarding a spectrum mask when using preamble puncturing, the terminal comprising: an authentication information storage unit that stores authentication information related to the certification; and a radio signal processing unit that transmits the authentication information for the region of use of the terminal to an access point.

2. The terminal according to claim 1, wherein the radio signal processing unit applies the preamble puncturing in accordance with a puncturing pattern broadcast by the access point.

3. An access point comprising: an authentication information storage unit that stores authentication information received from a terminal relating to authentication of a spectrum mask when preamble puncturing is used in a usage area where the access point is located; a puncturing pattern derivation unit that derives a puncturing pattern that specifies, based on the authentication information, that the authenticated terminal not use channel blocks that are expected to cause interference with existing systems that do not constitute a wireless LAN; and a radio signal processing unit that notifies the terminal of the puncturing pattern.

4. The access point according to claim 3, wherein the puncturing pattern derivation unit derives a puncturing pattern that specifies not to use channel blocks that are expected to cause interference between the terminal and other wireless LAN systems, regardless of the authentication information.

5. The access point according to claim 3, wherein the existing systems include weather radar, mobile radar, and fixed micro-communication systems when performing database reference type frequency sharing.

6. An access point having a puncturing pattern derivation unit that derives a puncturing pattern for each terminal that is specified so as not to use channel blocks that are expected to interfere with other wireless LAN systems, based on interference information between each terminal and other wireless LAN systems.

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