Communication device, control method thereof, and program

Abstract

To perform wireless communication using a MAC frame including a control field extended to make it possible to store control information more flexibly.SOLUTION: A communication device generates a MAC frame including an HT Control field in compliance with the IEEE802.11 series standard. In the generated MAC frame, the HT Control field is configured to include an A-Control subfield by first two bits each being set to 1. Further, the MAC frame is configured to further include a variable length extension field for extending the A-Control subfield included in the HT Control field. The communication device transmits the generated MAC frame to a peer device.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present invention relates to a communication device that performs wireless communication, a control method thereof, and a program. [Background technology]

[0002] The IEEE 802.11 series of standards is known as a wireless local area network (wireless LAN or WLAN) communication standard formulated by the IEEE (Institute of Electrical and Electronics Engineers). The IEEE 802.11 series of standards includes IEEE 802.11a / b / g / n / ac / ax standards, etc. For example, the IEEE 802.11ax (HE: High Efficiency) standard standardizes technology that uses OFDMA (Orthogonal Frequency Division Multiple Access) to achieve a high peak throughput of up to 9.6 gigabits per second (Gbps) as well as improve communication speeds under congested conditions (see Patent Document 1).

[0003] The format of the MAC (Medium Access Control) frame specified in the IEEE 802.11 series of standards has a 4-octet (32-bit) HT (High Throughput) Control field. When the first two bits of the HT Control field are both set to "1," the HT Control field is configured as an HE variant. In this case, a 30-bit subfield following the first two bits (B0 and B1) in the HT Control field can be assigned to a 4-bit (B2 to B5) Control ID subfield and a Control Information subfield. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2018-50133 Summary of the Invention [Problem to be solved by the invention]

[0005] As mentioned above, the HT Control field is currently assigned a length of 4 octets (32 bits). However, there is a possibility that the length of the HT Control field will become insufficient due to an increase in control information, for example, due to future functional expansion. In addition, the number of bits in the Control ID subfield, which is used to identify the type of control information stored in the Control Information subfield, may also become insufficient due to an increase in the type of control information.

[0006] Therefore, an object of the present invention is to provide a technique for performing wireless communication using a MAC frame including an expanded control field that allows for more flexible storage of control information. [Means for solving the problem]

[0007] A communication device according to one embodiment of the present invention is characterized in that it comprises: a generating means for generating a MAC frame including an HT Control field conforming to the IEEE 802.11 series standard, wherein the HT Control field is configured to include an A-Control subfield by setting each of the first two bits to 1, and the MAC frame is configured to further include a variable-length extension field for extending the A-Control subfield included in the HT Control field; and a transmitting means for transmitting the MAC frame generated by the generating means.

[0008] A communication device according to another aspect of the present invention is characterized in that it comprises: a generating means for generating a MAC frame including an HT Control field conforming to the IEEE 802.11 series standard, wherein the HT Control field is configured to include an A-Control subfield by setting each of the first two bits to 1, and the HT Control field is configured as an extended field in which the A-Control subfield is extended to a subfield of variable length; and a transmitting means for transmitting the MAC frame generated by the generating means.

[0009] A communication device according to another aspect of the present invention is characterized in that it comprises: a receiving means for receiving a MAC frame conforming to the IEEE 802.11 series standard, the MAC frame including an HT Control field; and an analyzing means for analyzing the MAC frame received by the receiving means, wherein the HT Control field is configured to include an A-Control subfield by setting each of the first two bits to 1, and the MAC frame is configured to further include a variable-length extension field for extending the A-Control subfield included in the HT Control field.

[0010] A communication device according to another aspect of the present invention is characterized in that it comprises: a receiving means for receiving a MAC frame conforming to the IEEE 802.11 series standard, the MAC frame including an HT Control field; and an analyzing means for analyzing the MAC frame received by the receiving means, wherein the HT Control field is configured to include an A-Control subfield by setting each of the first two bits to 1, and the HT Control field is configured as an extended field in which the A-Control subfield is extended to a subfield of variable length. [Effects of the Invention]

[0011] According to the present invention, it is possible to perform wireless communication using a MAC frame including an expanded control field that allows for more flexible storage of control information. [Brief explanation of the drawings]

[0012] [Figure 1] Diagram showing an example of a network configuration [Figure 2] A block diagram showing an example of the hardware configuration of a communication device. [Figure 3] A block diagram showing an example of the functional configuration of a communication device. [Figure 4] FIG. 10 is a diagram showing an example of a MAC frame format (comparison example). [Figure 5] A diagram showing an example of a MAC frame format [Figure 6] A diagram showing an example of the correspondence between the values ​​of the control ID subfield and their meanings. [Figure 7] A sequence diagram showing a procedure of communication processing by a communication device. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the invention according to the claims. Although the embodiments describe multiple features, not all of these multiple features are necessarily essential to the invention, and multiple features may be combined arbitrarily. Furthermore, in the accompanying drawings, the same reference numerals are used to designate the same or similar components, and redundant explanations will be omitted.

[0014] <Network configuration> 1 illustrates an example of the configuration of a network in which communication devices 101 and 102, which are communication devices according to an embodiment of the present disclosure, participate. In this example, the network 100 is a wireless network, and the communication devices 101 and 102 participate in the network 100.

[0015] The communication device 101 is an access point (AP) that serves to build the network 100. The communication device 102 is a station (STA) that serves to participate in the network 100 built by the AP (communication device 101). Note that while Fig. 1 illustrates a network configured with one AP and one STA, the number of APs and the number of STAs are not limited to this.

[0016] Each communication device is compatible with the IEEE802.11be (EHT: Extremely High Throughput or Extreme High Throughput) standard, which is the successor standard to the IEEE802.11ax (HE: High Efficiency) standard, as a wireless LAN communication standard. Each communication device is capable of wireless communication compliant with the IEEE802.11be standard. Each communication device is configured to be able to perform wireless communication in multiple frequency bands (in this embodiment, the 2.4 GHz band, the 5 GHz band, and the 6 GHz band). The frequency bands available to each communication device are not limited to these, and different frequencies, such as the 60 GHz band, may be available. Each communication device is configured to be able to communicate using bandwidths such as 20 MHz, 40 MHz, 80 MHz, 160 MHz, and 320 MHz. The bandwidths available to each communication device are not limited to these, and different bandwidths, such as 240 MHz and 4 MHz, may be available.

[0017] The communication devices 101 and 102 can realize multi-user (MU) communication by performing OFDMA (Orthogonal Frequency Division Multiple Access) communication conforming to the IEEE802.11be standard. Multi-user communication is communication in which signals from multiple users are multiplexed. In OFDMA communication, frequency resources are assigned to each STA so that parts of the divided frequency band (RUs: Resource Units) do not overlap between the STAs, and the frequency resources (carriers) assigned to each STA are orthogonal to each other. Therefore, the AP (communication device 101) can communicate with multiple STAs (communication devices 102) in parallel (simultaneously).

[0018] In this embodiment, the communication devices 101 and 102 are compliant with the IEEE 802.11be standard, but may also be compliant with at least one legacy standard that predates the IEEE 802.11be standard. The legacy standard is the IEEE 802.11a / b / g / n / ac / ax standard. In this embodiment, at least one of the IEEE 802.11a / b / g / n / ac / ax / be standards is referred to as an IEEE 802.11 series standard.

[0019] Furthermore, the communication devices 101 and 102 may support other communication standards such as Bluetooth (registered trademark), NFC (Near Field Communication), UWB (Ultra Wide Band), Zigbee, and MBOA (Multi Band OFDM Alliance) in addition to the IEEE802.11 series standards. UWB includes wireless USB, wireless 1394, Winet, etc. Furthermore, the communication devices 101 and 102 may also support a communication standard for wired communication such as a wired LAN.

[0020] The communication devices 101 and 102 are multilink devices (MLDs) that have the function of performing multilink communication, which establishes and communicates through multiple links (transmission paths) via multiple frequency channels. In multilink communication, multiple links are established and used between an AP MLD equipped with multiple APs and a Non-AP MLD (STA MLD) equipped with multiple STAs. In this embodiment, the communication device 101 operates as an AP MLD, and the communication device 102 operates as a Non-AP MLD.

[0021] In multi-link communication, multiple links established between the communication device 101 and the communication device 102 are established on different frequency channels. Furthermore, the channel spacing between the frequency channels on which the multiple links are established can be at least greater than 20 MHz. Here, the frequency channel refers to a frequency channel defined in the IEEE 802.11 series of standards, and refers to a frequency channel on which wireless communication compliant with the IEEE 802.11 series of standards can be performed. The IEEE 802.11 series of standards defines multiple frequency channels in each of the 2.4 GHz, 5 GHz, and 6 GHz frequency bands. Furthermore, the IEEE 802.11 series of standards defines the bandwidth of each frequency channel as 20 MHz. Note that a single frequency channel may be bonded with an adjacent frequency channel to utilize a bandwidth of 40 MHz or more.

[0022] The communication device 101 can improve the throughput of communication with the communication device 102 by establishing multiple links with the communication device 102, each via multiple frequency channels, to perform multilink communication. Note that the communication devices 101 and 102 may establish multiple links via different frequency bands in multilink communication. Alternatively, the communication devices 101 and 102 may establish multiple links via different channels included in the same frequency band. Furthermore, the multilink communication of the communication devices 101 and 102 may include a mixture of multiple links in the same frequency band and links in different frequency bands.

[0023] When performing multi-link communication, the communication devices 101 and 102 divide one piece of data and transmit it to the other device via multiple links. Alternatively, the communication devices 101 and 102 may transmit the same data in parallel via multiple links, using communication via one link as backup communication for communication via another link. Furthermore, the communication devices 101 and 102 may use different links depending on the type of frame and data to be transmitted.

[0024] Furthermore, the communication devices 101 and 102 may be capable of performing MIMO (Multiple-Input And Multiple-Output) communication. In this case, the communication devices 101 and 102 each have multiple antennas. The transmitting communication device transmits different stream signals from each antenna using the same frequency channel. The receiving communication device simultaneously receives all the multiple stream signals using multiple antennas, and separates and decodes the signals of each stream. In this way, by performing MIMO communication, the communication devices 101 and 102 can transmit and receive more data in the same time period than when not performing MIMO communication. Furthermore, when performing multi-link communication, the communication devices 101 and 102 may perform MIMO communication on some links.

[0025] The communication device 101 may be, for example, a wireless LAN router or a personal computer (PC), but is not limited to these. The communication device 102 may be, for example, a camera, a tablet terminal, a PC, a smartphone, a mobile phone, a headset, or a video camera, but is not limited to these. The communication devices 101 and 102 may also be information processing devices equipped with a wireless chip or the like capable of performing wireless communication in accordance with the IEEE802.11be standard. Note that the information processing device equipped with the wireless chip has an antenna for transmitting the generated signal.

[0026] <Hardware configuration of communication device> 2 is a block diagram showing an example of the hardware configuration of the communication device 101. The communication device 101 has a storage unit 201, a control unit 202, a function unit 203, an input unit 204, an output unit 205, a communication unit 206, and an antenna 207. Note that the communication device 102 may have the same hardware configuration as the communication device 101.

[0027] The storage unit 201 is configured with one or more memories such as a ROM (Read Only Memory) and / or a RAM (Random Access Memory). The storage unit 201 stores computer programs for performing various operations described below, and various information such as communication parameters for wireless communication. Note that other types of storage media such as a flexible disk, a hard disk, an optical disk, a magneto-optical disk, a CD-ROM, a CD-R, a magnetic tape, a non-volatile memory card, and a DVD may be used as the one or more memories constituting the storage unit 201. The storage unit 201 may also include multiple memories.

[0028] The control unit 202 is configured with one or more processors such as a CPU (Central Processing Unit) and / or an MPU (Micro Processing Unit). The control unit 202 controls the entire communication device 101 by reading and executing a computer program stored in the storage unit 201. The control unit 202 may be configured to control the entire communication device 101 in cooperation with the computer program and an OS (Operating System) stored in the storage unit 201. The control unit 202 may also be configured to include multiple processors such as multi-core processors and to control the entire communication device 101 using the multiple processors.

[0029] The control unit 202 generates data or signals (wireless frames) to be transmitted in communication with other communication devices. The control unit 202 further controls the function unit 203 to execute predetermined processes such as wireless communication, imaging, printing, and projection. The function unit 203 is hardware that enables the communication device 101 to execute predetermined processes.

[0030] The input unit 204 receives various operations from the user. The output unit 205 outputs various types of information to the user via a monitor screen or a speaker. Here, the output from the output unit 205 may be one or more of a display on a monitor screen, a sound output from a speaker, a vibration output, and the like. The input unit 204 and the output unit 205 may be realized as a single module, such as a touch panel display. Furthermore, the input unit 204 and the output unit 205 may be configured as an integral part of the communication device 101, or may be provided separately from the communication device 101.

[0031] The communication unit 206 controls wireless communication in accordance with the IEEE802.11be standard, etc. The communication unit 206 controls the antenna 207 to transmit and receive signals for wireless communication generated by the control unit 202. The communication device 101 transmits and receives various data such as image data, document data, and video data by communicating with the communication device 102 via the communication unit 206.

[0032] The communication unit 206 may be configured to control wireless communications compliant with other IEEE 802.11 series standards in addition to the IEEE 802.11be standard, and to control wired communications such as a wired LAN. If the communication device 101 supports the NFC standard, the Bluetooth standard, or the like in addition to the IEEE 802.11be standard, it may also be configured to control wireless communications compliant with these communication standards. If the communication device 101 is configured to be able to perform wireless communications compliant with multiple communication standards, it may have individual communication units and antennas corresponding to the different communication standards.

[0033] Antenna 207 is an antenna capable of communication in a predetermined frequency band (in this embodiment, 2.4 GHz band, 5 GHz band, and 6 GHz band). Although communication device 101 in this embodiment has one antenna, it may have a separate antenna for each frequency band. Furthermore, if communication device 101 has multiple antennas, it may have a corresponding communication unit 206 for each antenna. Note that antenna 207 may be provided separately from communication unit 206 as shown in FIG. 2, or may be configured together with communication unit 206 as a single module.

[0034] <Functional configuration of communication device> 3 is a block diagram showing an example of the functional configuration of the communication device 101. The communication device 101 has, as functional units, one or more communication control units 301, frame processing units 302, UI control units 303, and storage control units 304. For example, in order to establish multiple links in multi-link communication, the communication device 101 may have multiple communication control units 301 corresponding to the multiple links, respectively. Note that the communication device 102 may have the same functional configuration as the communication device 101.

[0035] The communication control unit 301 communicates with external devices such as the communication device 102 by controlling the communication unit 206 and the antenna 207. The communication control unit 301 transmits a radio frame including a MAC (Media Access Control) frame generated by the frame processing unit 302, receives a radio frame from the counterpart device, and delivers the received radio frame to the frame processing unit 302.

[0036] The frame processing unit 302 performs processing related to a frame (MAC frame) for wireless communication by the communication control unit 301. Specifically, the frame processing unit 302 generates a MAC frame to be transmitted to the counterpart device. The MAC frame is, for example, a management frame or a data frame (QoS data frame). The frame processing unit 302 configures the frame to be generated according to the setting data stored in the storage unit 201. In addition, the frame processing unit 302 analyzes the MAC frame received from the counterpart device by the communication control unit 301.

[0037] The UI control unit 303 accepts user operations via a touch panel or the like and outputs information to the user (such as screen display or voice output) by controlling the input unit 204 and the output unit 205. For example, the UI control unit 303 accepts a touch panel operation using the screen displayed by the output unit 205 from the user by the input unit 204. The UI control unit 303 performs various settings according to the accepted user operations, and stores setting data indicating the settings in the storage unit 201 via the storage control unit 304.

[0038] The storage control unit 304 accesses the storage unit 201 according to instructions from other functional units. The storage control unit 304 stores data in the storage unit 201 and reads data from the storage unit 201.

[0039] <MAC Frame Configuration (Comparative Example)> 4 shows, as a comparative example, an example of the format of a MAC frame transmitted and received between the communication device 101 and the communication device 102, which is the premise of each embodiment described below. The frame format shown in FIG. 4 complies with the IEEE 802.11 series standard and can be used, for example, in a QoS data frame or a management frame.

[0040] As shown in Figure 4, a frame has a 4-octet (32-bit) High Throughput (HT) Control field in part of the MAC header. When the first two bits (bits B0 and B1) of the HT Control field are both set to "1," the HT Control field is configured as an HE variant. In this case, the 30-bit subfield (bits B2 to B31) following the first two bits (B0 and B1) of the HT Control field is configured as an Aggregated Control (A-Control) subfield. The A-Control subfield contains information on the IEEE 802.11 series of standards (IEEE 802.11ax and its successors) that follow HE.

[0041] The A-Control subfield can contain one or more Control subfields. Each Control subfield consists of a 4-bit Control ID subfield and a variable-length Control Information subfield. The ID value stored in the Control ID subfield is used to identify the type of control information stored in the corresponding Control Information subfield.

[0042] As described above, currently, the HT Control field is assigned a length of 4 octets (32 bits). However, for example, due to an increase in control information associated with future function expansion, the length of the HT Control field may become insufficient. Also, the number of bits in the Control ID subfield used to identify the types of control information stored in the Control Information subfield may become insufficient due to an increase in the types of control information.

[0043] Therefore, in each of the following embodiments, an example of performing wireless communication using a MAC frame including an extended control field (Extended HT Control field) that can more flexibly store control information between the communication device 101 and the communication device 102 will be described.

[0044] [Embodiment 1] In Embodiment 1, an example of adding a variable-length extension field for extending the HT Control field (A-Control subfield) to a MAC frame based on an existing frame format as shown in FIG. 4 will be described.

[0045] <MAC Frame Configuration> FIG. 5(A) shows an example of the format of a MAC frame transmitted and received between the communication device 101 and the communication device 102 according to Embodiment 1. The frame format shown in FIG. 5(A) is an extension of the frame format shown in FIG. 4 and can be used, for example, in a QoS data frame or a management frame.

[0046] As shown in FIG. 5(A), the frame includes a Frame Control field 501, a Duration / ID field 502, an HT Control field 503, and an Extended HT Control field 504. These fields are part of the MAC header. The frame further includes a Frame Body field 505 and an FCS (Frame Check Sequence) field 506.

[0047] The Frame Body field 505 is a field in which data (information) to be transmitted is stored. In the case of a management frame, the Frame Body field 505 can be used to transmit, for example, the status or information of the device to the other device. The FCS field 506 stores a code used by the communication device receiving the MAC frame to verify whether or not there are any errors in the received frame. The receiving communication device verifies whether or not there are any errors in the received frame by comparing the code obtained by calculation based on the contents of the received frame with the code stored in the FCS field 506.

[0048] Note that the frame may contain fields other than those shown in Fig. 5(A), or some of the fields shown in Fig. 5(A) may not be present. For example, the MAC header of the frame may further contain an Address field indicating the MAC address of the destination, etc., and a Sequence Control field indicating the sequence number of the data to be transmitted, etc. Each field constituting the MAC header will be described below.

[0049] The Frame Control field 501 is used to identify the protocol version and frame type of the frame itself. For example, if the first two bits (B0 and B1) in the Frame Control field 501 are both "0", this indicates that the protocol version is 0. As an example, this embodiment targets frames whose protocol version is 0, but the protocol version is not limited to this. When the protocol version is 0, the type of the frame changes depending on the values ​​of the six bits (B2 to B7) following the first two bits. For example, if B2 and B3 are "00", this indicates that the type of the frame is a management frame, and if B2 and B3 are "01", this indicates that the type of the frame is a data frame.

[0050] The Duration / ID field 502 indicates, for example, when the frame is a management frame or a QoS data frame, the time during which the communication band is occupied by the frame and the response to the frame.

[0051] The HT Control field 503 is a field for storing control information, and is a field to which attribute information and additional information given for each frame are added. The HT Control field 503 is composed of multiple subfields, including a VHT (Very High Throughput) subfield 510, an HE subfield 511, a Control ID subfield 512, and a Length subfield 513.

[0052] The VHT subfield 510 and the HE subfield 511 are each assigned one bit. The VHT subfield 510 and the HE subfield 511 indicate the type of additional information to which the subfields following these subfields correspond. In this embodiment, the first two bits (B0 and B1) of the VHT subfield 510 and the HE subfield 511 in the HT Control field are both set to "1." This indicates that the subfields following these are A-Control subfields.

[0053] In this embodiment, as shown in Figure 5(A), the A-Control subfield 520 includes a Control ID subfield 512 and a Length subfield 513. The Control ID subfield 512 and the Length subfield 513 are provided when the VHT subfield 510 and the HE subfield 511 are both set to "1" (i.e., the A-Control subfield 520 is provided). The Control ID subfield 512 is a 4-bit subfield, similar to the Control ID included in the existing frame format shown in Figure 4. The 30-bit A-Control subfield 520 is composed of the 4-bit Control ID subfield 512 and the 26-bit Length subfield 513.

[0054] Fig. 6 shows an example of the correspondence between the values ​​of the control ID subfield and their meanings. The MAC frame in this embodiment is configured to further include an extension field by setting a specific value to the control ID subfield 512 included in the A-Control subfield 520. For example, as shown in Fig. 6, when the set value (control ID value) of the control ID subfield 512 is "14", an Extended HT Control field 504 is provided as an extension field within the frame. The Extended HT Control field 504 corresponds to a variable-length extension field for extending the A-Control subfield.

[0055] In the example of Fig. 5(A), an Extended HT Control field 504 is provided after the HT Control field 503. When the Control ID subfield 512 is set to a specific value ("14" in Fig. 6) in this way, this indicates that the type of the field (subfield) following the HT Control field 503 (A-Control subfield 520) is an Extended HT Control field (Extended Control ID subfield). Note that the specific value set in the Control ID subfield 512 may be a value other than "14" (for example, "15").

[0056] The length subfield 513 indicates the length of the Extended HT Control field 504 (extension field) that follows the subfield. The length indicated by the length subfield 513 may be, for example, a bit length or a byte length. The length subfield 513 may indicate information other than the length of the Extended HT Control field 504. For example, the length subfield 513 may indicate the number of control subfields (a set of subfields 514 to 516, described later) included in the Extended HT Control field 504 (extension field).

[0057] The length subfield 513 may not be present in the A-Control subfield 520, or the entire length subfield 513 may be filled with bits "0" or "1." Alternatively, a portion of the 26-bit subfields in the A-Control subfield 520, excluding the control ID subfield 512 (4 bits), may be used as the length subfield, and the remaining portion may be filled with bits "0" or "1."

[0058] The Extended HT Control field 504 is added as a variable-length extension field to extend the HT Control field (A-Control subfield) and constitutes part of the MAC header. The overall length (number of octets) of the Extended HT Control field 504 is variable. For example, the Extended HT Control field may be defined to have four octets.

[0059] The Extended HT Control field 504 includes one or more Control subfields 521. Each Control subfield 521 includes an Extended Control ID subfield 514, an Extended Control ID subfield 514, an EOH (End of HE control) subfield 515, and a Control Information subfield 516.

[0060] The control information subfield 516 stores control information to be added to the MAC frame. The control information includes various information related to the operation or function of the communication devices 101, 102, such as control information for optimizing the connection state or the number of queues in the buffer. The extended control ID subfield 514 stores an ID (identification information) corresponding to the control information in the corresponding control information subfield 516. The extended control ID subfield 514 is an additional control ID subfield that is added in addition to the control ID subfield 512. The extended control ID subfield 514 is configured to have a length (number of bits) necessary to identify the type of control information stored in the control information subfield 516. In other words, the length of the extended control ID subfield 514 can be determined depending on the number of types of control information.

[0061] The EOH subfield 515 indicates whether the control subfield 521 containing the EOH subfield is the end of the Extended HT Control field 504 (whether another control subfield 521 is to be added). For example, if the EOH subfield 515 is set to "1", one more control subfield 521 is added to the Extended HT Control field 504. On the other hand, if the EOH subfield 515 is set to "0", the control subfield 521 containing the EOH subfield is the end of the Extended HT Control field 504. In other words, no further control subfields are added to the Extended HT Control field 504. In this way, the EOH subfield 515 is an example of an end subfield that indicates whether the control subfield containing the EOH subfield is the end of an extended field.

[0062] The EOH subfield 515 does not have to be present in the control subfield 521. If the EOH subfield 515 is not present, it is possible to analyze how many more control subfields follow in the Extended HT Control field 504 based on, for example, the length of the Extended HT Control field 504 (extension field) indicated by the length subfield 513 or the number of control subfields.

[0063] <Processing Procedure> FIG. 7 is a sequence diagram showing the procedure of communication processing by the communication devices 101 and 102, and shows an example in which a MAC frame is transmitted from the communication device 101 to the communication device 102 via wireless communication conforming to the IEEE802.11 series standards.

[0064] In S701, the communication device 101 performs a frame generation process to generate a MAC frame to be transmitted to the communication device 102. The communication device 101 generates a MAC frame having the format shown in FIG. 5A in accordance with the setting data stored in the storage unit 201. The generated MAC frame is, for example, a management frame or a data frame (QoS data frame). In S702, the communication device 101 transmits the generated MAC frame to the communication device 102 via wireless communication.

[0065] When the communication device 102 receives the MAC frame transmitted from the communication device 101 via wireless communication, the communication device 102 performs frame analysis processing to analyze the received MAC frame in S703. In the analysis processing, the received MAC frame is analyzed according to the format shown in Fig. 5(A) to obtain the setting values ​​of each field or subfield and also obtain control information.

[0066] As described above, the communication device in this embodiment generates a MAC frame that conforms to the IEEE 802.11 series standards and includes an HT Control field 503. In the generated MAC frame, the HT Control field 503 is configured to include an A-Control subfield 520 by setting each of the first two bits to 1. Furthermore, the MAC frame is configured to further include a variable-length extension field for extending the A-Control subfield 520 included in the HT Control field 503. The communication device transmits the generated MAC frame to a partner device.

[0067] According to this embodiment, it is possible to add control information to a generated MAC frame while maintaining backward compatibility with the IEEE 802.11 series of standards. Furthermore, by newly providing an Extended HT Control field 504 as a variable-length extension field for extending the A-Control subfield 520, it is possible to add control information more flexibly. As a result, even if the types of control information increase, it is possible to prepare subfields with the number of bits required to store control ID values ​​corresponding to such types of control information. Therefore, it is possible to perform wireless communication between the communication device 101 and the communication device 102 using MAC frames including an extended control field (Extended HT Control field 504) that allows for more flexible storage of control information.

[0068] <Modification> The format of the MAC frame shown in Fig. 5(A) can be modified in various ways, as exemplified below. For example, the A-Control subfield 520 and the Extended HT Control field 504 (control subfield 521) may be configured to include a control ID subfield 512, an extended control ID subfield 514, a length subfield 513, an EOH subfield 515, and a control information subfield 516 in this order.

[0069] 5A, the length subfield 513 and the EOH subfield 515 may be omitted. In this case, the A-Control subfield 520 and the Extended HT Control field 504 (control subfield 521) may be configured to include the control ID subfield 512, the extended control ID subfield 514, and the control information subfield 516 in this order.

[0070] Figure 5(B) shows an example of such a MAC frame format. In the example of Figure 5(B), the A-Control subfield 520 is configured to include a control ID subfield 512 and an extended control ID subfield 514 (additional control ID subfield). Furthermore, the Extended HT Control field 504 (extension field) is configured to include a control information subfield 516 in which control information to be added to the MAC frame is stored. The extended control ID subfield 514 stores an ID (identification information) corresponding to the control information in the control information subfield 516 (Extended HT Control field 504).

[0071] By using such a MAC frame format, it becomes possible to perform wireless communication using a MAC frame including an extended control field (Extended HT Control field 504) that allows for more flexible storage of control information between the communication device 101 and the communication device 102. Furthermore, compared to embodiment 1 (FIG. 5(A)) and embodiment 2 (FIG. 5(C)) described later, it is possible to reduce the number of subfields in the extended field (Extended HT Control field 504), enabling a more efficient frame configuration.

[0072] [Embodiment 2] In the second embodiment, an example will be described in which a MAC frame including an extended control field is used so that control information can be stored more flexibly by extending part of the existing frame format (HT Control field) as shown in Fig. 4. The following mainly describes the parts that are different from the first embodiment.

[0073] Fig. 5(C) shows an example of the format of a MAC frame transmitted and received between the communication device 101 and the communication device 102 according to the first embodiment. The frame format shown in Fig. 5(C) is an extension of the frame format shown in Fig. 4, and can be used, for example, in a QoS data frame or a management frame.

[0074] As shown in Fig. 5(C), the frame includes a Frame Control field 501, a Duration / ID field 502, and an Extended HT Control field 507. These fields are part of the MAC header. The frame also includes a Frame Body field 505 and an FCS field 506. The Frame Control field 501, the Duration / ID field 502, the Frame Body field 505, and the FCS field 506 are the same as in the first embodiment. Note that, as in the first embodiment, the frame may include fields other than those shown in Fig. 5(C), or some of the fields shown in Fig. 5(C) may not be present.

[0075] In the IEEE 802.11 series standards, the length of the HT Control field is specified as 4 octets (32 bits). In this embodiment, the HT Control field itself shown in Fig. 4 is extended to a variable-length field shown as Extended HT Control field 507 in Fig. 5(C). As described above, the HT Control field is configured to include an A-Control subfield 522 by setting each of the first two bits (B0 and B1) in the field to "1". In this embodiment, the A-Control subfield 522 in the HT Control field is extended to a variable-length subfield. In this way, by configuring the HT Control field as an extended field (Extended HT Control field 507), it becomes possible to use a MAC frame that includes an extended control field that allows for more flexible storage of control information.

[0076] As shown in Figure 5(C), the Extended HT Control field 507 includes a 1-bit VHT subfield 510 and a 1-bit HE subfield 511. These correspond to the first two bits (B0 and B1) in the HT Control field, and are each set to "1." Therefore, like the HT Control field shown in Figure 4, an A-Control subfield 522 is placed after these subfields.

[0077] The A-Control subfield 522 shown in Figure 5(C) includes a control ID subfield 512, similar to Figures 4, 5(A), and 5(C). In this embodiment, the MAC frame is configured to include the A-Control subfield 522, which is expanded into a variable-length subfield by setting the control ID subfield 512 to a specific value. For example, when the set value (control ID value) of the control ID subfield 512 is "14," the A-Control subfield 522 is expanded into a variable-length subfield. Note that the specific value set in the control ID subfield 512 may be a value other than "14" (for example, "15").

[0078] The variable-length A-Control subfield 522 includes a control ID subfield 512 and one or more control subfields 521. Each control subfield 521 includes an extended control ID subfield 514, an EOH subfield 515, and a control information subfield 516, which are the same as those in the first embodiment.

[0079] The EOH subfield 515 indicates whether the control subfield 521 containing the EOH subfield is the end of the A-Control subfield 522 (Extended HT Control field). For example, when "0" is set in the EOH subfield 515, the control subfield 521 containing the EOH subfield is the end of the A-Control subfield 522 (Extended HT Control field 507). In this way, the EOH subfield 515 is an example of an end subfield that indicates whether the control subfield containing the EOH subfield is the end of the A-Control subfield.

[0080] Note that a subfield (padding subfield) for adjusting the length of the control information subfield 516 to 8 bits may be added after the control subfield 521. For example, if the length from the VHT subfield 510 to the last control information subfield 516 in the Extended HT Control field 507 is (n*8+5) bits, a 3-bit padding subfield is provided.

[0081] The format of the MAC frame of this embodiment can be modified in various ways. For example, each control subfield 521 may be configured to include subfields 510 to 516. As in the first embodiment, the EOH subfield 515 does not have to be present in the control subfield 521. For example, the Extended Control ID subfield 514 may be followed by a length subfield 513 indicating the length of the Extended HT Control field 507 (extension field).

[0082] The processing procedure for wireless communication using the MAC frame as described above, which is executed by the communication devices 102 and 103, is the same as that in the first embodiment (FIGS. 5A and 5B).

[0083] The communication device in this embodiment generates a MAC frame that conforms to the IEEE 802.11 series standards and includes an HT Control field 522. In the generated MAC frame, the HT Control field is configured to include an A-Control subfield 522 by setting each of the first two bits to 1. Furthermore, the HT Control field is configured as an extended field (Extended HT Control field 507) in which the A-Control subfield 522 is extended into a subfield of variable length. The communication device transmits the generated MAC frame to a remote device.

[0084] According to this embodiment, it is possible to extend the length of the HT Control field, and to assign more control information to the HT Control field. By applying this embodiment, even when extending HLA (HE Link Adaptation) control for EHT, it is possible to secure a subfield of the length required to store control information for extension such as NSS (number of spatial streams) in the Extended HT Control field 507. On the other hand, if the control information subfield 516 is short, it is also possible to set the length of the Extended HT Control field 507 to four octets or less, enabling a more flexible frame configuration to be realized.

[0085] [Other embodiments] The present invention can also be realized by supplying a program that realizes one or more functions of the above-described embodiments to a system or device via a network or a storage medium, and having one or more processors in the computer of the system or device read and execute the program.The present invention can also be realized by a circuit (e.g., ASIC) that realizes one or more functions.

[0086] The disclosure of this specification includes the following communication device, control method thereof, and program. (Item 1) A communication device, A generating means for generating a MAC frame including an HT Control field conforming to the IEEE 802.11 series standard, the HT Control field being configured to include an A-Control subfield by setting each of the first two bits to 1, and the MAC frame being configured to further include a variable-length extension field for extending the A-Control subfield included in the HT Control field; a transmitting means for transmitting the MAC frame generated by the generating means; A communication device comprising: (Item 2) The communication device described in item 1, characterized in that the MAC frame is configured to further include the extension field by setting a control ID subfield included in the A-Control subfield to a specific value. (Item 3) The A-Control subfield includes the Control ID subfield and a Length subfield indicating the length of the extension field. 3. The communication device according to item 2. (Item 4) The extension field includes one or more control subfields, each of which includes a control information subfield in which control information to be added to the MAC frame is stored, and an additional control ID subfield in which an ID corresponding to the control information is stored. 4. The communication device according to item 2 or 3, (Item 5) the A-Control subfield includes the Control ID subfield and a Length subfield indicating the length of the extension field; The length subfield indicates the number of control subfields included in the extension field. 5. The communication device according to item 4, (Item 6) the A-Control subfield and the extension field are configured to include the Control ID subfield and one or more control subfields; Each of the one or more control subfields includes a control information subfield in which control information to be added to the MAC frame is stored, and an additional control ID subfield in which an ID corresponding to the control information is stored. 3. The communication device according to item 2. (Item 7) The A-Control subfield and the extension field are configured to further include a length subfield indicating the length of the extension field. 7. The communication device according to item 6, (Item 8) Each of the one or more control subfields further includes an end subfield that indicates whether the control subfield is the end of the extension field. 8. The communication device according to any one of items 4 to 7, (Item 9) the A-Control subfield is configured to include the Control ID subfield and an Additional Control ID subfield; The MAC frame is configured such that control information added to the MAC frame is stored in the extension field, and an ID corresponding to the control information is stored in the additional control ID subfield. 3. The communication device according to item 2. (Item 10) A communication device, A generating means for generating a MAC frame including an HT Control field conforming to the IEEE 802.11 series standard, wherein the HT Control field is configured to include an A-Control subfield by setting each of the first two bits to 1, and the HT Control field is configured as an extended field in which the A-Control subfield is extended into a subfield of variable length; a transmitting means for transmitting the MAC frame generated by the generating means; A communication device comprising: (Item 11) The MAC frame is configured to include the A-Control subfield expanded to a variable-length subfield by setting a Control ID subfield included in the A-Control subfield to a specific value. 11. The communication device according to item 10. (Item 12) The A-Control subfield includes the control ID subfield and one or more control subfields, each of which includes a control information subfield in which control information to be added to the MAC frame is stored, and an additional control ID subfield in which an ID corresponding to the control information is stored. Item 12. A communication device according to item 11. (Item 13) The A-Control subfield further includes a Length subfield indicating the length of the A-Control subfield. Item 13. A communication device according to item 12. (Item 14) Each of the one or more control subfields further includes an end subfield that indicates whether the control subfield is the end of the A-Control subfield. 14. The communication device according to item 12 or 13, (Item 15) A communication device, a receiving means for receiving a MAC frame including an HT Control field in accordance with the IEEE 802.11 series standard; an analysis means for analyzing the MAC frame received by the receiving means, wherein the HT Control field is configured to include an A-Control subfield by setting each of the first two bits to 1, and the MAC frame is configured to further include a variable-length extension field for extending the A-Control subfield included in the HT Control field; A communication device comprising: (Item 16) Item 16. The communication device according to item 15, wherein the MAC frame is configured to further include the extension field by setting a control ID subfield included in the A-Control subfield to a specific value. (Item 17) The A-Control subfield includes the Control ID subfield and a Length subfield indicating the length of the extension field. 17. The communication device according to item 16, (Item 18) The extension field includes one or more control subfields, each of which includes a control information subfield in which control information to be added to the MAC frame is stored, and an additional control ID subfield in which an ID corresponding to the control information is stored. 18. The communication device according to item 16 or 17, (Item 19) the A-Control subfield includes the Control ID subfield and a Length subfield indicating the length of the extension field; The length subfield indicates the number of control subfields included in the extension field. Item 19. A communication device according to item 18, characterized in that (Item 20) the A-Control subfield and the extension field are configured to include the Control ID subfield and one or more control subfields; Each of the one or more control subfields includes a control information subfield in which control information to be added to the MAC frame is stored, and an additional control ID subfield in which an ID corresponding to the control information is stored. 17. The communication device according to item 16, (Item 21) The A-Control subfield and the extension field are configured to further include a length subfield indicating the length of the extension field. 21. A communication device according to item 20, characterized in that (Item 22) Each of the one or more control subfields further includes an end subfield that indicates whether the control subfield is the end of the extension field. 22. A communication device according to any one of items 18 to 21, characterized in that (Item 23) the A-Control subfield is configured to include the Control ID subfield and an Additional Control ID subfield; The MAC frame is configured such that control information added to the MAC frame is stored in the extension field, and an ID corresponding to the control information is stored in the additional control ID subfield. 17. The communication device according to item 16, (Item 24) A communication device, a receiving means for receiving a MAC frame including an HT Control field in accordance with the IEEE 802.11 series standard; an analysis means for analyzing the MAC frame received by the receiving means, wherein the HT Control field is configured to include an A-Control subfield by setting the first two bits to 1, and the HT Control field is configured as an extended field in which the A-Control subfield is extended into a subfield of variable length; A communication device comprising: (Item 25) The MAC frame is configured to include the A-Control subfield expanded to a variable-length subfield by setting a Control ID subfield included in the A-Control subfield to a specific value. 25. The communication device according to item 24, (Item 26) The A-Control subfield includes the control ID subfield and one or more control subfields, each of which includes a control information subfield in which control information to be added to the MAC frame is stored, and an additional control ID subfield in which an ID corresponding to the control information is stored. 26. The communication device according to item 25, (Item 27) The A-Control subfield further includes a Length subfield indicating the length of the A-Control subfield. 27. The communication device according to item 26, (Item 28) Each of the one or more control subfields further includes an end subfield that indicates whether the control subfield is the end of the A-Control subfield. 28. A communication device according to item 26 or 27, (Item 29) A method for controlling a communication device, comprising: A generation step of generating a MAC frame including an HT Control field conforming to the IEEE 802.11 series standard, wherein the HT Control field is configured to include an A-Control subfield by setting each of the first two bits to 1, and the MAC frame is configured to further include a variable-length extension field for extending the A-Control subfield included in the HT Control field; a transmitting step of transmitting the MAC frame generated in the generating step; 10. A method for controlling a communication device, comprising: (Item 30) A method for controlling a communication device, comprising: A generation step of generating a MAC frame including an HT Control field conforming to the IEEE 802.11 series standard, wherein the HT Control field is configured to include an A-Control subfield by setting each of the first two bits to 1, and the HT Control field is configured as an extension field in which the A-Control subfield is extended into a subfield of variable length; a transmitting step of transmitting the MAC frame generated in the generating step; 10. A method for controlling a communication device, comprising: (Item 31) A method for controlling a communication device, comprising: a receiving step of receiving a MAC frame including an HT Control field in accordance with the IEEE 802.11 series standard; an analyzing step of analyzing the MAC frame received in the receiving step, wherein the HT Control field is configured to include an A-Control subfield by setting each of the first two bits to 1, and the MAC frame is configured to further include a variable-length extension field for extending the A-Control subfield included in the HT Control field; 10. A method for controlling a communication device, comprising: (Item 32) A method for controlling a communication device, comprising: a receiving step of receiving a MAC frame including an HT Control field in accordance with the IEEE 802.11 series standard; an analyzing step of analyzing the MAC frame received in the receiving step, wherein the HT Control field is configured to include an A-Control subfield by setting each of the first two bits to 1, and the HT Control field is configured as an extension field in which the A-Control subfield is extended into a subfield of variable length; 10. A method for controlling a communication device, comprising: (Item 33) A program for causing a computer to execute each step of the communication device control method described in any one of items 29 to 32.

[0087] The invention is not limited to the above-described embodiments, and various changes and modifications can be made without departing from the spirit and scope of the invention. Accordingly, the following claims are appended to apprise the public of the scope of the invention. [Explanation of symbols]

[0088] 100: Network, 101: Communication device (AP MLD), 102: Communication device (Non-AP MLD), 202: Control unit, 206: Communication unit

Claims

1. A communication device, A generating means for generating a MAC frame that includes an HT Control field conforming to the IEEE 802.11 series standard, the HT Control field being configured to include an A-Control subfield by setting each of the first two bits to 1, and the MAC frame being configured to further include a variable-length extension field for extending the A-Control subfield included in the HT Control field; a transmitting means for transmitting the MAC frame generated by the generating means; A communication device comprising:

2. 2. The communication device according to claim 1, wherein the MAC frame is configured to further include the extension field by setting a control ID subfield included in the A-Control subfield to a specific value.

3. The A-Control subfield includes the control ID subfield and a length subfield indicating the length of the extension field.

3. The communication device according to claim 2.

4. The extension field includes one or more control subfields, and each of the one or more control subfields includes a control information subfield in which control information to be added to the MAC frame is stored, and an additional control ID subfield in which an ID corresponding to the control information is stored.

4. The communication device according to claim 2 or 3.

5. The A-Control subfield includes the Control ID subfield and a Length subfield indicating the length of the extension field; The length subfield indicates the number of control subfields included in the extension field.

5. The communication device according to claim 4.

6. Each of the one or more control subfields further includes an end subfield that indicates whether the control subfield is the end of the extension field.

5. The communication device according to claim 4.

7. The A-Control subfield and the extension field are configured to include the control ID subfield and one or more control subfields; Each of the one or more control subfields includes a control information subfield in which control information to be added to the MAC frame is stored, and an additional control ID subfield in which an ID corresponding to the control information is stored.

3. The communication device according to claim 2.

8. The A-Control subfield and the extension field are configured to further include a length subfield indicating the length of the extension field.

8. The communication device according to claim 7,

9. the A-Control subfield is configured to include the Control ID subfield and an Additional Control ID subfield; The MAC frame is configured such that control information added to the MAC frame is stored in the extension field, and an ID corresponding to the control information is stored in the additional control ID subfield.

3. The communication device according to claim 2.

10. A communication device, A generating means for generating a MAC frame including an HT Control field conforming to the IEEE 802.11 series standard, wherein the HT Control field is configured to include an A-Control subfield by setting each of the first two bits to 1, and the HT Control field is configured as an extended field in which the A-Control subfield is extended to a subfield of variable length; a transmitting means for transmitting the MAC frame generated by the generating means; A communication device comprising:

11. The MAC frame is configured to include the A-Control subfield extended to a variable-length subfield by setting a control ID subfield included in the A-Control subfield to a specific value.

11. The communication device according to claim 10.

12. The A-Control subfield includes the control ID subfield and one or more control subfields, and each of the one or more control subfields includes a control information subfield in which control information to be added to the MAC frame is stored, and an additional control ID subfield in which an ID corresponding to the control information is stored.

12. The communication device according to claim 11.

13. The A-Control subfield further includes a length subfield indicating the length of the A-Control subfield.

13. The communication device according to claim 12.

14. Each of the one or more control subfields further includes an end subfield indicating whether the control subfield is the end of the A-Control subfield.

14. The communication device according to claim 12 or 13.

15. A communication device, A receiving means for receiving a MAC frame including an HT Control field conforming to the IEEE 802.11 series standard; an analysis means for analyzing the MAC frame received by the receiving means, wherein the HT Control field is configured to include an A-Control subfield by setting each of the first two bits to 1, and the MAC frame is configured to further include a variable-length extension field for extending the A-Control subfield included in the HT Control field; A communication device comprising:

16. The communication device according to claim 15, wherein the MAC frame is configured to further include the extension field by setting a control ID subfield included in the A-Control subfield to a specific value.

17. The A-Control subfield includes the control ID subfield and a length subfield indicating the length of the extension field.

17. The communication device according to claim 16.

18. The extension field includes one or more control subfields, and each of the one or more control subfields includes a control information subfield in which control information to be added to the MAC frame is stored, and an additional control ID subfield in which an ID corresponding to the control information is stored.

18. A communication device according to claim 16 or 17.

19. The A-Control subfield includes the Control ID subfield and a Length subfield indicating the length of the extension field; The length subfield indicates the number of control subfields included in the extension field.

20. The communication device according to claim 18,

20. Each of the one or more control subfields further includes an end subfield that indicates whether the control subfield is the end of the extension field.

20. The communication device according to claim 18,

21. The A-Control subfield and the extension field are configured to include the control ID subfield and one or more control subfields; Each of the one or more control subfields includes a control information subfield in which control information to be added to the MAC frame is stored, and an additional control ID subfield in which an ID corresponding to the control information is stored.

17. The communication device according to claim 16.

22. The A-Control subfield and the extension field are configured to further include a length subfield indicating the length of the extension field.

22. The communication device according to claim 21 .

23. the A-Control subfield is configured to include the Control ID subfield and an Additional Control ID subfield; The MAC frame is configured such that control information added to the MAC frame is stored in the extension field, and an ID corresponding to the control information is stored in the additional control ID subfield.

17. The communication device according to claim 16.

24. A communication device, A receiving means for receiving a MAC frame including an HT Control field conforming to the IEEE 802.11 series standard; an analysis means for analyzing the MAC frame received by the receiving means, wherein the HT Control field is configured to include an A-Control subfield by setting each of the first two bits to 1, and the HT Control field is configured as an extended field in which the A-Control subfield is extended to a subfield of variable length; A communication device comprising:

25. The MAC frame is configured to include the A-Control subfield extended to a variable-length subfield by setting a control ID subfield included in the A-Control subfield to a specific value.

25. The communication device of claim 24.

26. The A-Control subfield includes the control ID subfield and one or more control subfields, and each of the one or more control subfields includes a control information subfield in which control information to be added to the MAC frame is stored, and an additional control ID subfield in which an ID corresponding to the control information is stored.

26. The communication device of claim 25.

27. The A-Control subfield further includes a length subfield indicating the length of the A-Control subfield.

27. The communication device of claim 26.

28. Each of the one or more control subfields further includes an end subfield indicating whether the control subfield is the end of the A-Control subfield.

28. A communication device according to claim 26 or 27.

29. A method for controlling a communication device, comprising: a generating step of generating a MAC frame conforming to the IEEE 802.11 series standard, including an HT Control field, wherein the HT Control field is configured to include an A-Control subfield by setting each of the first two bits to 1, and the MAC frame is configured to further include a variable-length extension field for extending the A-Control subfield included in the HT Control field; a transmitting step of transmitting the MAC frame generated in the generating step; 10. A method for controlling a communication device, comprising:

30. A method for controlling a communication device, comprising: a generating step of generating a MAC frame including an HT Control field conforming to the IEEE 802.11 series standard, wherein the HT Control field is configured to include an A-Control subfield by setting each of the first two bits to 1, and the HT Control field is configured as an extension field in which the A-Control subfield is extended to a subfield of variable length; a transmitting step of transmitting the MAC frame generated in the generating step; 10. A method for controlling a communication device, comprising:

31. A method for controlling a communication device, comprising: a receiving step of receiving a MAC frame conforming to the IEEE 802.11 series standard and including an HT Control field; an analyzing step of analyzing the MAC frame received in the receiving step, wherein the HT Control field is configured to include an A-Control subfield by setting each of the first two bits to 1, and the MAC frame is configured to further include a variable-length extension field for extending the A-Control subfield included in the HT Control field; 10. A method for controlling a communication device, comprising:

32. A method for controlling a communication device, comprising: a receiving step of receiving a MAC frame conforming to the IEEE 802.11 series standard and including an HT Control field; an analyzing step of analyzing the MAC frame received in the receiving step, wherein the HT Control field is configured to include an A-Control subfield by setting each of the first two bits to 1, and the HT Control field is configured as an extended field in which the A-Control subfield is extended to a subfield of variable length; 10. A method for controlling a communication device, comprising:

33. A program for causing a computer to execute each step of the method for controlling a communication device according to any one of claims 29 to 32.

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