Communication device, control method, and program

Abstract

To provide a mechanism for transmitting different data in place of communication of certain data during communication of a wireless frame in which the certain data is communicated, as one of objectives.SOLUTION: A communication device generates and transmits an A-MPDU (Aggregation-MAC Protocol Data Unit) in which multiple MAC frames, each including a MAC header and a payload, are bundled. At this time, when a specific condition is satisfied, the communication device bundles multiple MAC frames, including at least a first MAC frame for a first destination and a second MAC frame for a second destination, for multiple different destinations into one A-MPDU and transmits the A-MPDU.SELECTED DRAWING: Figure 9

Description

[Technical field]

[0001] The present invention relates to a communication device that performs wireless communication. [Background technology]

[0002] The Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard is known as a communication standard for wireless local area networks (wireless LANs). The IEEE 802.11be standard and its successors aim to improve communication efficiency and throughput by having multiple access point devices (hereinafter simply referred to as APs) operate in cooperation with each other.

[0003] Furthermore, Patent Document 1 discloses a technique called R-TWT (Restricted Target Wake Time) that provides a period that can be used for communication of data that requires low latency, and transmits the data that requires low latency during that period. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] US Patent Application Publication No. 2022 / 0070772 Summary of the Invention [Problem to be solved by the invention]

[0005] The aforementioned R-TWT technology can reduce latency when transmitting regularly occurring data at scheduled periods.

[0006] On the other hand, there are cases where data requiring low latency occurs outside the scheduled period. In order to transmit such data with low latency, it is necessary to realize prioritized transmission using a technique other than R-TWT.

[0007] The present invention has been made in consideration of at least one of the above problems. One aspect of the present invention aims to provide a mechanism for interrupting a frame including data to a certain destination with data having a higher priority for the other destination and transmitting the interrupted frame. [Means for solving the problem]

[0008] A communication device as one aspect of the present invention has a transmission control means for generating and transmitting an A-MPDU (Aggregation-MAC Protocol Data Unit) that bundles together multiple MAC frames, each including a Media Access Control (MAC) header and a payload, and the transmission control means is characterized in that, when specific conditions are satisfied, the transmission control means controls the bundling and transmission of multiple MAC frames intended for multiple different destinations, including at least a first MAC frame intended for a first destination and a second MAC frame intended for a second destination, into a single A-MPDU. Effect of the Invention

[0009] According to one aspect of the present invention, it becomes possible to transmit data for one destination while a radio frame communicating data for another destination is being transmitted. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 illustrates an example of a configuration of a network system. [Diagram 2] A diagram illustrating an example of the hardware configuration of a communication device (AP / STA). [Diagram 3] A diagram showing an example of the software configuration of a communication device (AP / STA). [Figure 4] 13 is a flowchart illustrating an example of communication control in an AP. [Diagram 5] 11 is a flowchart showing an example of communication control in a STA. [Figure 6] 10 is a schematic diagram showing an example of capability information communicated between devices; FIG. [Figure 7] 1 is a schematic diagram showing an example of a PPDU that enables interrupt communication of low-latency data. [Figure 8] FIG. 11 is a sequence diagram showing an example of communication between an AP and a STA. [Figure 9] 1 is a schematic diagram showing an example of the flow of data communication between an AP and a STA. [Figure 10] 13 is a diagram showing an example of a frame communicated in the second embodiment. [Figure 11] FIG. 13 is a schematic diagram showing a modified example of a PPDU that enables interrupt communication. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, the embodiments will be described in detail with reference to the attached drawings. Note that the following embodiments do not limit the invention according to the claims. Although the embodiments describe a plurality of features, not all of these features are essential to the invention, and the plurality of features may be combined in any manner. Furthermore, in the attached drawings, the same reference numbers are used for the same or similar configurations, and duplicated descriptions are omitted.

[0012] <First embodiment> An example of the configuration of a network system according to this embodiment is shown in Fig. 1. This network system includes one access point device (hereinafter, simply referred to as AP, AP STA, or access point) and two station devices (hereinafter, simply referred to as STA, Non-AP STA, or station). Hereinafter, AP 101 and STAs 102-103 are collectively referred to as communication devices.

[0013] The AP 101 is configured to be able to execute wireless frame communication conforming to the IEEE802.11bn standard, which is the successor standard to the IEEE802.11be standard and has a target maximum transmission speed of 46.08 Gbps. The STAs 102 to 103 are also configured to be able to execute wireless frame communication conforming to the successor standard. In FIG. 1, 110 and 111 indicate data communication between the devices.

[0014] IEEE is an abbreviation for the Institute of Electrical and Electronics Engineers. The main features of 802.11bn, the successor standard to 802.11be, are highly reliable communication, low latency communication, and improved throughput during congestion. Wireless frames communicated under this successor standard are also called UHR (Ultra High Reliability) PPDU. PPDU is an abbreviation for physical layer Protocol Data Unit.

[0015] The names IEEE802.11bn and UHR standards are given for convenience in consideration of the goals and features of the successor standards, and may be different names when the standards are fully formulated. However, please note that this specification and the appended claims are essentially successors to the 802.11be standard and are applicable to all successor standards.

[0016] In addition, in FIG. 1, as an example, a wireless communication network including one AP and two STAs is shown, but the number of these may be more or less than that shown. In addition, the AP 101 and the STAs 102 to 103 are described as supporting communication (transmission and reception) of UHR PPDU of the 802.11bn standard, but this is not limited to this. In addition, they can be configured to support communication of PPDU of a legacy standard that is a standard that precedes the 802.11bn standard. Specifically, the AP 101 and the STAs 102 to 103 can be configured to support transmission and reception of PPDU of the IEEE802.11a / b / g / n / ac / ax / be standard, etc.

[0017] The AP 101 provides a network 100 to the STAs. The STAs 102 to 103 are STAs that participate in the network provided by the AP 101. In FIG. 1, a case is illustrated in which the STAs 102 to 103 participate in the network provided by the AP 101.

[0018] The AP 101 and the STAs 102 to 103 can also be configured to support wireless communication based on other communication standards such as Bluetooth (registered trademark), NFC, Bluetooth (registered trademark) LE (Low Energy), etc. NFC is an abbreviation for Near Field Communication.

[0019] The AP 101 can also be configured to support wired communication using an Ethernet cable or wired communication using optical fiber. In this embodiment, it is assumed that the AP 101 is connected to the Internet via an Ethernet cable. Specific examples of the AP 101 and the STAs 102 to 103 include, but are not limited to, a wireless LAN router and a personal computer (PC). The APs 101 and 102 to 103 may also be information processing devices such as wireless chips that support the transmission and reception of UHR PPDU. Specific examples of the 102 to 103 include, but are not limited to, a camera, a tablet, a smartphone, a PC, a mobile phone, a video camera, a projector, and a wearable device such as smart glasses.

[0020] In addition, each communication device such as AP101, STA102 to 103 can communicate at frequencies of 2.4 GHz band, 3.6 GHz band, 5 GHz band, 6 GHz band, 45 GHz band called millimeter wave, and 60 GHz band. The frequency band used by each communication device is not limited to these, and a different frequency band such as Sub1 GHz band may be used. In addition, AP101 and STA102 can communicate using bandwidths of 20 GHz, 40 MHz, 80 MHz, 160 MHz, 320 MHz, 540 MHz, 640 MHz, 1080 MHz, and 2160 MHz. The bandwidth used by each communication device is not limited to these, and a different bandwidth such as 240 MHz and 4 MHz may be used.

[0021] Recently, the demand for low latency communication has been increasing in wireless communication. For example, the 802.11be standard provides a function called R-TWT (Restricted Target Wake Time) that provides a period that can be used for communication that requires low latency in order to meet the demand for low latency communication. This R-TWT function can reduce the latency when transmitting regularly occurring data in a scheduled period. On the other hand, data that requires low latency may occur outside the aforementioned scheduled period. In order to transmit such data with low latency, it is necessary to realize preferential low latency transmission using a technology other than R-TWT.

[0022] In this embodiment, a mechanism is provided for transmitting data having a higher priority for a certain destination by interrupting a frame including data for another destination, as will be described in detail below.

[0023] <Device configuration> 2 shows an example of the hardware configuration of a communication device (AP and STA). As an example of the hardware configuration, the communication device 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, although it is assumed in this embodiment that the communication device has multiple antennas, the communication device may have only one antenna.

[0024] The storage unit 201 is configured with both or either one of a ROM and a RAM, and stores various information such as programs for performing various operations described below and communication parameters for wireless communication. RAM stands for Random Access Memory, and ROM stands for Read Only Memory. Note that, as the storage unit 201, in addition to memories such as ROM and RAM, storage media such as non-volatile storage devices such as hard disks and SSDs (Solid State Drives) may be used.

[0025] The control unit 202 is configured with, for example, a processor such as a CPU or MPU, an ASIC (Application Specific Integrated Circuit), a DSP (Digital Signal Processor), an FPGA (Field Programmable Gate Array), etc. Here, CPU is an acronym for Central Processing Unit, and MPU is an acronym for Micro Processing Unit. The control unit 202 executes the programs stored in the storage unit 201 and controls the entire device by operating hardware circuits such as ASIC. The control unit 202 may control the entire device in cooperation with the programs stored in the storage unit 201 and an OS (Operating System).

[0026] The control unit 202 also controls the functional unit 203 to perform predetermined processing such as imaging, printing, and projection. The functional unit 203 is hardware for the device to perform predetermined processing. For example, when the communication device is a camera such as a digital still camera or a smartphone having a camera, the functional unit 203 is an imaging unit that performs imaging processing of surrounding images via a camera unit (not shown) that the communication device has. For example, when the communication device is a printer, the functional unit 203 is a printing unit that performs printing processing on a sheet such as paper based on print data obtained from the outside via wireless communication. For example, when the communication device is a projector or smart glasses, the functional unit 203 is a projection unit that performs projection processing of image data or video data obtained from the outside via wireless communication. In the case of smart glasses, the projection surface is the retina of an end user. The data processed by the functional unit 203 may be data stored in the storage unit 201, or may be data communicated with other APs or STAs via a communication unit 206 described later.

[0027] The input unit 204 receives various operations from the user. The output unit 205 outputs various types of information to the user. Here, the output by the output unit 205 includes at least one of display on a screen, audio output by a speaker, vibration output, and the like. Note that both the input unit 204 and the output unit 205 may be realized by a single module, such as a touch panel.

[0028] The communication unit 206 controls wireless communication in accordance with the IEEE802.11 standard series. In this embodiment, the communication unit 206 can transmit and receive UHR PPDU, which is a wireless frame of the IEEE802.11bn standard, and PPDU corresponding to earlier standards in cooperation with the antenna 207. The antenna 207 is an antenna capable of transmitting and receiving signals in at least one of the frequency bands of the sub-GHz band, the 2.4 GHz band, the 5 GHz band, the 6 GHz band, the 7 GHz band, and the 60 GHz band, for example.

[0029] In addition, if the communication device is compatible with the aforementioned NFC standard, Bluetooth standard, wired LAN network, etc., the communication unit 206 can be configured to control wireless communication and wired communication that comply with these communication standards.

[0030] <Functional configuration> Next, the functional configuration of the communication devices (AP 101, STAs 102 to 103) will be described with reference to Fig. 3. Fig. 3 is a block diagram illustrating the functional configuration of AP 101.

[0031] The communication device includes a MAC frame creation unit 301 , an aggregation control unit 302 , a wireless communication control unit 303 , a low-latency frame control unit 304 , and an interpretation unit 305 .

[0032] Each function will be described below. MAC frame creation unit 301 of AP 101 creates MAC (Media Access Control) frames for STA 102 and STA 103. Specifically, creation unit 301 generates MAC frames such as data frames including data to be transmitted to each STA and management frames to be notified to each STA.

[0033] The aggregation control unit 302 cooperates with each unit such as the low latency frame control unit 304, the wireless communication control unit 303, the communication unit 206, and the antenna 207 to control the generation and transmission of A-MPDU. Specifically, the control unit 302 controls communication so as to aggregate a plurality of MAC frames into one A-MPDU in order to transmit the MAC frame generated by the MAC frame creation unit 301 to the outside, and transmit the A-MPDU to the outside. A-MPDU is an abbreviation for Aggregation-MAC Protocol Data Unit, and means a PPDU in which a plurality of MAC frames are concatenated and stored in the data portion of a PPDU consisting of one PHY preamble and a data portion.

[0034] The aggregation control unit 302 also has a function of rescheduling a frame to be transmitted in order to interrupt and transmit the low latency data, based on an interrupt instruction received from another functional unit.

[0035] The wireless communication control unit 303, which receives an instruction for data transmission and data to be transmitted from the control unit 302, cooperates with the communication unit 206 and the antenna 207 to generate a signal indicating a UHR PPDU in which MAC frames are aggregated in the A-MPDU format and transmits it to the outside. The wireless communication control unit 303 also cooperates with the communication unit 206 and the antenna 207 to control the reception of frames transmitted by other communication devices. The configuration of the UHR PPDU transmitted by the AP 101 will be described later. The frame received by the control unit 303 is appropriately decoded by the interpretation unit 305. When the interpretation unit 305 interprets the received frame and determines that it is a data frame directed to itself, it extracts the data contained in the payload and transfers the data to a higher layer (IP layer, etc.) not shown. When the interpretation unit 305 interprets the received frame as a management frame directed to itself, it performs communication control in cooperation with each unit based on the result of decoding the frame.

[0036] The low-latency frame control unit 304 detects the occurrence of low-latency data to be transmitted to another STA during the process of creating and transmitting an A-MPDU containing data for a certain STA. The control unit 304 also cooperates with each unit to perform control for interrupt transmission of the detected low-latency data. Specifically, the control unit 304 transmits an interrupt instruction to the MAC frame creation unit 301, including information specifying the destination of the MAC frame and the storage address of the data to be interrupted. The MAC frame creation unit 301 that has received the interrupt instruction generates a MAC frame to be transmitted by interrupting the A-MPDU based on the specified information. The creation unit 301 then transmits information about the MAC frame and an instruction to cause rescheduling of the transmission order to the aggregation control unit 302. The aggregation control unit 302 that has received the information and the instruction to cause rescheduling performs rescheduling of the frame group to be transmitted. When the data order is changed by the rescheduling, the control unit 302 notifies the wireless communication control unit 303 of the transmission instruction and the data order so that the MAC frames are transmitted in the rescheduled order. For example, consider a case where signals corresponding to MAC frames 1-2 addressed to destination 1 are generated and transmitted, and the succeeding MAC frame 3 is buffered and scheduled for transmission. In this case, the transmission order is scheduled so that the MAC frame 4 addressed to destination 2, which should be transmitted in an interrupt manner, is transmitted before the MAC frame 3 addressed to destination 1, which is a position where rescheduling is possible. The low latency frame control unit 304 of the AP 101 also manages information of each STA connected to the AP 101. At this time, the information of each STA is managed so that each STA can distinguish whether the STA has the ability to accept interrupt reception, as described later. The information is used to identify the STA that can perform interrupt reception in the control described later. The MAC frame 1 is an example of a first MAC frame, and the MAC frame 4 is an example of a second MAC frame. Also, the destination 1 is an example of a first destination, and the destination 2 is an example of a second destination.

[0037] Note that STA102 to STA103 also have functional units similar to those of AP 101. That is, STA102 to STA103 can make each unit cooperate to generate and transmit a frame addressed to AP 101, and receive and decode a frame transmitted from AP 101.

[0038] <Low latency data interrupt control> Specific interrupt processing will be described below with reference to Figures 4 to 9. First, the overall communication sequence will be described with reference to Figure 8.

[0039] Fig. 8 is a sequence diagram for explaining an example of a processing flow when an interrupt process of low latency data is performed from AP 101 to a STA. Note that Fig. 8 assumes that STA 103 has already established a connection to AP 101 and is in a state where data communication can be performed. Also, Fig. 8 illustrates a flow when STA 102 newly establishes a connection to AP 101, and then A-MPDU transmission is performed to STA 102 and STA 103.

[0040] First, the STA102 transmits an Association Request to establish a connection with the AP101 (S801). In the Association Request transmitted to an AP such as the AP101, the STA such as the STA102 includes an information element including capability information notifying the presence or absence of capability to receive interruption reception of low latency data. The information element may be included in a Probe Request frame. Also, the information element may be included in a Beacon frame or a Probe Response frame from the AP such as the AP101 to notify the STA of the presence or absence of capability to transmit interruption transmission of low latency data.

[0041] The information element including the capability information exchanged between the STA and the AP will be described with reference to Fig. 6. Fig. 6 is a schematic diagram showing an example of an Extended Capabilities Element 600, which is an information element including capability information indicating that the STA has the capability to receive interrupt reception of low latency data.

[0042] An element 600 includes an element ID field 601, a length field 602, and an extended capabilities field 603. The element ID field 601 stores "127" indicating that the element is an extended capabilities element. The length field 602 stores a value indicating the length of the element.

[0043] The Extended Capabilities field 603 is a field composed of a bit group indicating the support status of various capabilities. In this embodiment, the field 603 is configured to include a 1-bit Emergency Frame Capable field 604. Storing 1 in the Emergency Frame Capable field indicates that the device has the capability to accept interrupt reception of low latency data or has the capability to perform interrupt transmission. Storing 0 in the Emergency Frame Capable field indicates that the device does not have the capability to accept interrupt reception of low latency data or has the capability to perform interrupt transmission.

[0044] In this embodiment, as an example, the Extended Capability Element indicates the presence or absence of the capability to receive interruption reception of low latency data / the capability to perform interruption transmission, but the method of indicating this is not limited to this. For example, an information element for indicating the capability of UHR non-AP STA or UHR AP STA may be newly defined. In this case, the information element may be configured to include the above-mentioned Emergency Frame Capable field, and the presence or absence of capability may be indicated in this field.

[0045] Furthermore, when a UHR AP STA or a UHR non-AP STA supports the ability to accept interrupt reception / transmit the above-mentioned low latency data as a mandatory, the notification of the ability can be omitted. In this case, it is sufficient to assume that the STA / AP supports UHR PPDU and thus has the ability to accept interrupt reception / transmit. The aforementioned control unit 304 manages these frames and the above-mentioned presumption judgment so that STAs that are deemed to have the ability to accept interrupt reception can be distinguished from STAs that are deemed not to have the ability to accept interrupt reception.

[0046] Returning to the explanation of Fig. 8, when the AP 101 receives an Association Request from the STA 102, it transmits an Association Response to the STA 102 (S802). As described above, the Association Response can include an information element indicating whether or not the STA 102 has the capability to perform interrupt transmission of low latency data. Note that the AP 101 of this embodiment controls to transmit an Association Response including an information element indicating that the AP 101 has the capability to perform interrupt transmission of low latency data.

[0047] By the processing of S801 to S802, the STA 102 establishes a connection with the AP 101. After this, a procedure such as a 4-way handshake can be performed to generate a key to be used for encrypted communication.

[0048] Next, data communication after the connection establishment process and the process for encrypted communication as required will be described.

[0049] Next, the AP 101 and the STA 102 transmit and receive an ADDBA Request and an ADDBA Response to each other in order to transmit and receive an A-MPDU (S803 to S806). When the transmission and reception is completed, it becomes possible to transmit and receive an A-MPDU that combines multiple frames. Note that the presence or absence of the ability to accept interrupt reception of low latency data / the ability to transmit interrupt transmission can also be indicated in the ADDBA Request / Response.

[0050] Next, AP 101 transmits A-MPDUs addressed to STA 102 and STA 103 (S807). FIG. 8 illustrates a case in which a MAC frame addressed to STA 102 is followed by a MAC frame addressed to STA 103, which is transmitted as an interrupt, and then a MAC frame addressed to STA 102, which has been moved down in the transmission order as a result of the interrupt, is transmitted. AP 101 also transmits Trigger Frames to receive Acks from STA 102 and STA 103. Having received the Trigger Frames, STAs 102 to 103 transmit acknowledgements to AP 101 (S808). With the above procedure, data can be exchanged between the AP and the STAs using A-MPDUs including interrupt data.

[0051] Next, the frame transmission exemplified in S807 in Fig. 8 will be supplemented with Fig. 9. Fig. 9 is a schematic diagram showing an example of the flow of data communication between an AP and a STA. As shown in Fig. 9, the AP 101 transmits one UHR PPDU in which multiple MAC frames are bundled in the A-MPDU format to the outside. Each of these MAC frames has a field indicating a destination address, and the first MAC frame and the third MAC frame store the MAC address of the STA 102, which is the main destination. The second MAC frame stores the MAC address of another STA 103, which is the destination of the low latency data.

[0052] The interpretation units 305 of the STAs 102 and 103 appropriately interpret the MAC frames included in the received PPDU, and interpret and process the MAC frames directed to themselves. The Trigger Frame included at the end of the frame is transmitted to both the STAs 102 and 103. Therefore, it is received and interpreted appropriately by both STAs. As a result of the interpretation, the STAs 102 to 103 can transmit an acknowledgement response indicating the reception status of the data.

[0053] A more detailed format of the UHR PPDU transmitted by the AP 101 to the STA 102 will be described with reference to Fig. 7. Fig. 7 is a schematic diagram for explaining the format of the UHR PPDU transmitted by the AP 101 to the STAs 102 to 103. The UHR PPDU as the A-MPDU transmitted by the AP 101 in S807 is composed of a PHY preamble 701 and a data portion, and the data portion includes multiple MAC frames.

[0054] The PHY preamble 701 includes a training field for timing and frequency in the physical layer, channel estimation, and a SIGNAL field that indicates information required for receiving the data section. From the beginning, the PHY preamble 701 includes an L-STF (Non-HT Short Training field), an L-LTF (Non-HT Long Training field), an L-SIG (non-HT SIGNAL field), and an RL-SIG (Repeated non-HT SIGNAL field). This is followed by a U-SIG (Universal SIGNAL field) and a UHR-SIG (UHR SIGNAL field). The first three bits of the U-SIG include a PHY Version Identifier field (not shown), and this field stores a value indicating UHR. For example, this value can be "1". After the UHR-SIG, the UHR-STF and UHR-LTF used for timing and frequency synchronization and channel estimation are included.

[0055] The U-SIG and UHR-SIG store information required for decoding the UHR PPDU. Fields closely related to the present case will be briefly described. The U-SIG includes a UL / DL field 710, a BSS Color field 711, a LL Data preemption suggestion field 712, a PPDU Type And Compression Mode field 713, a UHR-SIG MCS field 714, and a Number Of Non-OFDMA Users field 715. The UHR-SIG also includes a STA-ID field 716, an MCS field 717, and a Beamformed field 718.

[0056] The UL / DL field 710 indicates whether the frame is UL or DL. When the AP 101 transmits data, it is DL communication regardless of whether it contains multiple MAC frames. Therefore, the AP 101 stores 0 in this field. The BSS Color field 711 stores BSS coloring information that specifies which access point provides the PPDU. The AP 101 sets a BSS color value for itself so that it does not overlap with surrounding access points. The AP 101 then sets the BSS color value set for itself in the field 712. The value of the field 712 is used by the STA that received the PPDU to determine whether the PPDU is directed to the network to which the STA belongs or to another network. This determination is realized by the STA such as STA 102 or STA 103 storing the BSS color value of the network to which the STA belongs and comparing the BSS color value included in the received PPDU with the BSS color value stored in the STA. Note that BSS is an abbreviation for Basic Service Set.

[0057] Next, the LL Data preemption suggestion field 712 is a field that indicates whether or not a MAC frame preemption of low latency data may occur.

[0058] Storing a "1" in this field indicates that a MAC frame interrupt for low latency data may occur. Storing a "0" in this field indicates that it may not. This information is used by the STA to determine whether to listen for an interrupt for low latency data.

[0059] The PPDU Type and Compression Mode field 713 indicates the type of PPDU. In this embodiment, the AP 101 sets "1" in this field. In the IEEE 802.11be standard, "3" in this field means a reserved value. This reserved value can also be used as a value to inform the STA whether or not an interruption of a MAC frame of low latency data can occur. In this case, instead of including the field 712 in the U-SIG, the AP 101 sets "3" in the PPDU Type and Compression Mode field 713 to indicate that the PPDU is a PPDU that can cause an interruption of a MAC frame of low latency data. In this way, the STA can be configured to indicate that the PPDU is a PPDU that can cause an interruption of a MAC frame of low latency data by setting "3" in the field 713. In this case, the STA refers to the value of the field 713 and determines whether or not to wait for interruption reception of low latency data.

[0060] Next, the UHR-SIG MCS field 714 defines the MCS (Modulation and Coding Scheme) indicating the modulation method, coding rate, etc. of the UHR-SIG. The value of the field 714 is information necessary for interpreting the following UHR-SIG. Next, the UHR-SIG will be described. The Number Of Non-OFDMA Users field 715 is set with the number of users who will communicate simultaneously when a frame is transmitted to multiple STAs simultaneously in a MU-MIMO frame. MU-MIMO is an abbreviation for Multi User Multiple Input Multiple Output. In this embodiment, in order to enable multiple STAs with different positional relationships to transmit A-MPDU data, the antenna 207 is made to function as an omni-antenna and a signal constituting the A-MPDU is transmitted in an omnidirectional manner without using techniques such as MIMO or beamforming. Therefore, "1" is set in the field 715. Next, one or more user fields that store information for users who are destinations of the PPDU are stored in the UHR-SIG. In this embodiment, a user field for one user is provided. This field includes a STA-ID field 716, an MCS field 717, and a Beamformed field 718.

[0061] The MCS field 717 stores the MCS indicating the modulation method, coding rate, etc. of the data field, that is, the MAC frame. The value indicating the MCS is used by the STA to decode the data field. When the AP 101 transmits a PPDU indicating that an interruption of a MAC frame of low latency data may occur, the AP 101 may set an MCS value that allows the data to be received even by the STA with the worst communication status among the STAs that may be the target of communication. That is, the AP 101 manages the MCS to be used for communication with each STA for each STA. Then, the AP 101 determines the MCS corresponding to the STA with the worst communication status as the MCS of the data section from among the MCSs of the STAs that may be the target of communication. Then, the determined MCS is set in the field 717 illustrated in FIG. 7. By setting the MCS value in this way, even the STAs that are far from the AP 101 in terms of their positional relationship can properly receive the interruption data.

[0062] Next, the STA-ID field 716 stores an ID for identifying the receiving STA or an ID indicating the group of the receiving STA. In this embodiment, it is assumed that the AP 101 stores "0" in the field 716. However, this is not limited to this, and it can also be configured to store the STA that is the main transmission destination (for example, the STA-ID corresponding to the destination of the first MAC frame). In addition, it can also be configured to assign a common Group ID to STAs such as STA102, STA103, etc. that have the ability to accept interrupt reception of low latency data, and store the Group ID in the field 716. Finally, the Beamformed field 718 indicates whether the Beamform steering matrix is ​​used in a non-MU-MIMO allocation. In this embodiment, the AP 101 sets "0" in this field to transmit an omnidirectional signal as described above.

[0063] Next, the data field of the PPDU in the A-MPDU format will be described. Various MAC frames are stored in this data field. Each MAC frame includes a MAC Header field 702, a Frame Body field 703, and an FCS field 704. The MAC Header field 702 includes an Address field 721, in which the destination MAC address of each MAC frame is stored. The Frame Body field 703 is the frame body in which the contents of the MAC frame are stored. In the case of a data frame, the contents of the data to be transmitted are stored in this field. The FCS field 704 is a field for checking.

[0064] 7 illustrates an example in which the MAC address of STA102 is stored in MAC Header field 702#1, and the MAC address of STA103 is stored in MAC Header field 702#2. Also illustrated is an example in which the MAC address of STA102 is stored in the subsequent MAC Header field 702#3. Descriptions such as "#1" and "#2" indicate the order of the MAC frames in A-MPDU, with "#1" indicating that it is an element of the first MAC frame, "#2" indicating that it is an element of the second MAC frame, and "#N" indicating that it is an element of the Nth MAC frame.

[0065] The MAC frame added to the end of the PPDU is a Trigger Frame for initiating an acknowledgement, as described with reference to Figures 8 and 9. The AP 101 stores a broadcast address in the MAC Header field 702#N of this Trigger Frame.

[0066] Next, the interruption transmission control executed by the AP 101 of this embodiment will be described with reference to Fig. 4 and Fig. 5. Fig. 4 is a flowchart showing an excerpt of the data transmission process related to the interruption control executed by the AP 101, which is a communication device. Fig. 5 is a flowchart showing an excerpt of the data reception process related to the interruption control executed by the STAs, such as the STA 102 and STA 103, which are communication devices.

[0067] Each process shown in the flowchart of Fig. 4 is executed by the processor of the control unit 202 of the AP 101 executing a computer program stored in the storage unit 201. Each process shown in the flowchart of Fig. 5 is executed by the processor of the control unit 202 of the STA such as the STA 102 or STA 103 executing a computer program stored in the storage unit 201. Note that some of the processes such as transmission, modulation, reception, and decoding in Figs. 4 and 5 are realized by the processor of the control unit 202 of each communication device, the communication unit 206, and the ASIC, DSP, FPGA, etc. of the control unit 202 in cooperation with each other. Note that when it is desired to clearly indicate the subject of the process, the functional unit described in Fig. 3 will be used as the subject.

[0068] In S401, the control unit 202 of the AP 101 determines whether there is data to be transmitted to the connected STAs such as STA102 and STA103. If the control unit 202 of the AP 101 determines that there is data to be transmitted to the connected STAs such as STA102 and STA103, the process proceeds to S402. On the other hand, if the control unit 202 of the AP 101 does not determine that there is data to be transmitted to the connected STAs such as STA102 and STA103, the process waits for the occurrence of transmission data. If it determines that there is data to be transmitted, the control unit 202 also identifies the STA that will be the main transmission destination in the subsequent transmission process at this timing, and determines the STA as the main transmission destination.

[0069] Next, in S402, the control unit 202 attempts to acquire a transmission opportunity by checking whether the channel is in an idle state during the waiting time for collision avoidance determined randomly. If it is confirmed that the channel is in an idle state during the waiting time for collision avoidance, the control unit 202 determines that it has acquired a transmission opportunity. If the control unit 202 determines that it has acquired a transmission opportunity, it proceeds to S403. On the other hand, if the operating channel is busy, or if another communication device acquires a transmission opportunity and starts data transmission during its waiting time, making the operating channel busy, it determines that it has not acquired a transmission opportunity. If the control unit 202 determines that it has not acquired a transmission opportunity, it waits until the channel becomes idle again, and then attempts to reacquire a transmission opportunity.

[0070] In S403, the control unit 202 determines a TXOP based on the amount of data to be transmitted to the STA such as the STA102, and generates a PHY preamble to transmit data during the determined TXOP. TXOP is an abbreviation for Transmission Opportunity, and indicates the occupancy time of the channel. The control unit 202 cooperates with the communication unit 206 and the antenna 207 to transmit a signal corresponding to the preamble to the outside. At this time, the AP101 generates a PHY preamble including information indicating that an interruption of a MAC frame of low latency data may occur. Note that, when it is determined that the transmission data to be transmitted to one destination is data with high urgency in the first place, a PHY preamble that does not indicate that an interruption of a MAC frame of low latency data may occur may be generated. In this case, the AP101 may generate and transmit a normal A-MPDU in which multiple MAC frames to one destination are bundled. In this way, when it is intended to transmit data with high urgency, it is possible to transmit an A-MPDU to one destination in which interruption is not considered as in the past, without implementing interrupt control described later.

[0071] Returning to the explanation of Fig. 4, a case where control is performed taking interrupts into consideration will now be explained. In S404, the low latency frame control unit 304 judges whether transmission data addressed to a party other than the main transmission destination is stored and / or newly stored as data to be transmitted. If it is determined that transmission data addressed to a party other than the main transmission destination is stored and / or newly stored as data to be transmitted, the process proceeds to S405. On the other hand, if it is determined that transmission data addressed to a party other than the main transmission destination is not stored as data to be transmitted, the process proceeds to S407.

[0072] In S405, the control unit 304 judges whether the type of the data destined for the different party is urgent data such as low latency data, etc. If it is judged to be urgent data such as low latency data, the process proceeds to S406, and if it is not urgent data such as low latency data, the process proceeds to S407.

[0073] One example of satisfying a specific condition is that the condition that transmission data intended for a different party is stored and that the type of the transmission data is highly urgent data such as low latency data.

[0074] Next, data generation and transmission control will be described using S406 to S408. Note that the processing of S406 to S408 is actually performed asynchronously with the functional units 301 to 304 linked to each other.

[0075] First, the generation and transmission of data frames to the primary transmission destination will be described. In S407, the MAC frame creation unit 301 sequentially generates MAC frames storing data to be transmitted to the primary transmission destination. Then, in S408, the aggregation control unit 302 manages the MAC frames that are generated by the creation unit 301 and are ready to be transmitted, and schedules the transmission order. Then, based on the scheduled transmission order, the control unit 302 cooperates with the wireless communication control unit 303, the communication unit 206, and the antenna 207 to transmit to the outside a signal corresponding to the MAC frame generated by the above-mentioned control as part of the A-MPDU. The communication unit 206 controls the antenna 207 to transmit the signal omnidirectionally.

[0076] On the other hand, in S406, the control unit 202 cooperates with the MAC frame creation unit 301 to generate a MAC frame including low latency data. Specifically, the low latency frame control unit 304 identifies the destination of the low latency data. Then, the control unit 304 transmits an interrupt instruction to the MAC frame creation unit 301, the interrupt instruction including a MAC address indicating the destination of the data and information specifying a storage address of the interrupting data. The creation unit 301 receives the interrupt instruction and generates one or more MAC frames including low latency data based on the interrupt instruction. When the MAC frame of the low latency data is generated, the creation unit 301 transmits information of the MAC frame and an instruction to cause rescheduling of the transmission order to the aggregation control unit 302.

[0077] When the control unit 302, which operates asynchronously with the creation unit 301, receives the information and an instruction to cause rescheduling, it reschedules the group of frames to be transmitted so that the interrupt frame is transmitted with priority. When the rescheduling is performed, the control unit 302 further notifies the wireless communication control unit 303 of the instruction to be transmitted and the order of data so that the MAC frames are transmitted in the rescheduled order. As a result, in S408, signals corresponding to the group of frames are transmitted in the rescheduled order. If the rescheduling is not performed, in S408, the control unit 302 notifies the wireless communication control unit 303 of the instruction to be transmitted and the order of data so that the MAC frames are transmitted in the order based on the original scheduling as appropriate. The control unit 303, which has received the notification of the transmission instruction and the order of data, cooperates with the communication unit 206 and the antenna 207 to transmit signals corresponding to the MAC frames generated in S506 and S407 to the outside.

[0078] Next, in S409, the control unit 202 judges whether or not the acquired TXOP remains. If it is judged that the acquired TXOP remains, the process proceeds to S410, and if it is judged that the acquired TXOP does not remain, the process proceeds to S411.

[0079] In S410, the control unit 202 judges whether there is data to be transmitted. If it is judged that there is data to be transmitted, the process proceeds to S404, and the subsequent MAC frame generation and transmission process is continued. If it is judged that there is no data to be transmitted, the process proceeds to S411. In S411, the creation unit 301 generates a MAC frame corresponding to the above-mentioned Trigger Frame, transmits a signal corresponding to the generated frame to the outside in cooperation with each unit, and completes the transmission of the A-MPDU. Through the series of controls described above, when an A-MPDU frame that communicates data to a certain destination is being transmitted or being prepared for transmission, data to another destination can be interrupted in the A-MPDU and transmitted.

[0080] Next, data reception control in the STAs such as STA102 and STA103 will be described with reference to FIG.

[0081] In S501, the control unit 202 of the STA analyzes the preamble of the received PPDU and compares whether the BSS color value stored in the BSS Color field 711 of the preamble is the same as the BSS color value to which the STA belongs. If the comparison results in the same value, it is determined that a PPDU with the BSS color to which the STA belongs specified has been received, and the process proceeds to S502. If the comparison results in different values, it is determined that a PPDU with the BSS color of the network to which the STA belongs has not been received, and the STA waits for the reception of a PPDU with the BSS color of the network to which the STA belongs specified. The control unit 202 may set a NAV during the transmission of a PPDU for another BSS. NAV is an abbreviation for Network Allocation Vector, and means a transmission prohibition period.

[0082] In S502, the control unit 202 analyzes the preamble of the received PPDU and judges whether or not the interruption of data is suggested. Specifically, if the preamble contains information indicating that an interruption of a MAC frame of low latency data may occur, it is judged that an interruption is suggested, and the process proceeds to S503. On the other hand, if the preamble contains information that does not indicate that an interruption of a MAC frame of low latency data may occur, or does not contain information indicating whether an interruption may occur, it is judged that an interruption is not suggested, and the process proceeds to S516. This may be judged, for example, based on whether the value of the LL Data preemption suggestion field 712 of the PHY preamble shown in FIG. 7 is 1. As a modified example, it may be judged based on whether the value of the above-mentioned field 713 is "3". Furthermore, it may be judged based on whether the value of the STA-ID field 716 is the above-mentioned special value "0".

[0083] Next, the control in the case where no interrupt is indicated will be described. In S516, the wireless communication control unit 303 and the interpretation unit 305 work together to interpret the preamble and the MAC frame head included in the beginning of the received PPDU to determine whether or not the frame is addressed to the unit. Specifically, if the unit's own STA-ID is stored in the STA-ID field of the preamble, the unit determines that the frame is addressed to the unit. If a group ID including the unit itself or an ID indicating a broadcast is stored, the unit further refers to the value of the Address field 721 included in the MAC Header field 702 to determine whether or not the frame is addressed to the unit. If the unit determines that the frame is addressed to the unit, the process proceeds to S517. On the other hand, if the unit determines that the frame is not addressed to the unit, the process proceeds to S518.

[0084] In S517, the wireless communication control unit 303 and the interpretation unit 305 cooperate to decode all MAC frames included in the received PPDU. The interpretation unit 305 provides the data obtained as a result of the decoding to a higher layer, and performs communication control in cooperation with each unit based on the decoding result. When the control unit 202 completes the decoding of the received PPDU, the process proceeds to S519. Meanwhile, in S518, the control unit 202 sets the NAV during the period in which a PPDU not addressed to itself is being transmitted. In addition, the control unit 202 may control each piece of hardware constituting the STA to transition to a power save mode in order to reduce power consumption.

[0085] Next, the control when an interrupt is indicated will be described. In S503, the wireless communication control unit 303 and the interpretation unit 305 cooperate to determine whether or not the first MAC frame is addressed to the device itself. The criteria for this determination are the same as those for determining whether or not the MAC frame is addressed to the device itself, explained in S516. If it is determined that the first MAC frame is addressed to the device itself, the process proceeds to S511, and if it is determined that the first MAC frame is not addressed to the device itself, the process proceeds to S504.

[0086] Next, the control of the decoding process and discard process in the STA to be interrupted when a PPDU suggesting interrupt control is received will be described.

[0087] In S511 to S512, the wireless communication control unit 303 and the interpretation unit 305 interpret the MAC frame and determine whether or not the address is addressed to the unit itself. The interpretation unit 305 decodes the Frame Body of the MAC frame that is determined to be addressed to the unit itself, and discards the frame that is determined not to be addressed to the unit itself without interpreting the Frame Body. When the control unit 202 completes the decoding process and interpretation process for one MAC frame, it advances the process to S513.

[0088] In S513, the wireless communication control unit 303 and the interpretation unit 305 judge whether or not the end of the PPDU has been reached. If it is judged that the end of the PPDU has been reached, the process proceeds to S519. On the other hand, if it is judged that the end of the PPDU has not been reached, the process proceeds to S511, where the destination of the next MAC frame is judged, and decoding or discarding is performed based on the judgment result.

[0089] Finally, the control of the decoding process and discard process in a non-interrupt target STA when a PPDU that suggests interrupt control is received will be described.

[0090] In S504, the control unit 202 judges whether or not the STA is in a standby state waiting for an interruption of a frame including low latency data. If it is judged to be in a standby state, the process proceeds to S505, and if it is judged not to be in a standby state, the process proceeds to S509. In addition to whether or not the STA is in a standby state, in S504, whether or not the STA waits for reception of an interruption frame may be switched depending on whether or not a value indicating a Group ID to which the STA belongs is stored in the STA-ID in the PHY preamble. More specifically, if the STA judges that the PPDU is addressed to a Group ID to which the STA does not belong, the STA may execute the process of S509 without waiting for reception. In S509, the control unit 202 performs the same NAV setting process as described in S518 and the process of transitioning to the power save mode as desired.

[0091] Meanwhile, in S505 to S507, the same decoding process, discarding process, and end-of-stream confirmation process as in S511 to S513 described above are repeated. With this process, the STA waiting for an interrupt frame can obtain low-latency data addressed to itself by decoding only the MAC frame that was interrupted for itself.

[0092] Finally, in S519, the control unit 202 transmits an Ack frame to the AP 101, which responds to the reception of the successfully decoded MAC frame. Specifically, when the STA 102 and STA 103 receive the A-MPDU from the AP 101, they respond with an Ack or a Block Ack according to the decoded Trigger Frame. Note that it is also possible to configure the STA 102 and STA 103 not to respond with an Ack for an interrupt frame. In that case, the exchange of the Trigger Frame at the end of the A-MPDU described above can be omitted. Also, it is not necessary to add a Trigger Frame to the end of the A-MPDU. In this case, the STA 102 and STA 103 are configured to transmit a Multi-User Block Ack Request (MU-BAR) again in order to receive a Block Ack from the AP 101. In this case, the AP 101 receives a Block Ack from the STA 102 and STA 103 as a response to the MU-BAR frame.

[0093] When a STA transmits a Block Ack, it performs scoring of the sequence number for each MAC frame and transmits a bitmap in which the bit corresponding to the sequence number of the received and decoded MAC address is set to 1. In this embodiment, the AP 101 manages the sequence number series of the MAC frame for each destination. In other words, if a MAC frame addressed to another device is inserted along the way, the sequence number series assigned to the inserted MAC frame is assigned a sequence number series different from the sequence number series used in communication with the main transmission destination. Therefore, even when the interrupted STA or the interrupting STA transmits a Block Ack, it is possible to transmit a BA according to each series.

[0094] The above-described procedure makes it possible to insert a MAC frame addressed to another STA in the middle of an A-MPDU addressed to a certain STA. This makes it possible to transmit an interrupt frame without being affected by the overhead required for acquiring the right to transmit or the overhead of the PHY preamble.

[0095] <Second embodiment> In the first embodiment, a case is illustrated in which an STA that has the ability to receive low-latency data as an interrupt and is waiting for the interrupt reception waits for the interrupt reception. In the second embodiment, in addition to the control described in the first embodiment, a negotiation is performed in advance between the AP and the STA as to whether or not the STA wants to receive low-latency data. Then, the STA that has performed the negotiation in advance to receive low-latency data waits for the interrupt. Note that the hardware configuration and software configuration of the communication device are the same as those in the first embodiment, and therefore the description is omitted.

[0096] The frames used in the negotiation will be described below with reference to Fig. 10. Fig. 10(a) is an example of an Emergency Request Action Frame that a STA transmits to an AP. Fig. 10(b) is an example of an Emergency Response Action Frame that an AP transmits to a STA.

[0097] A STA that wishes to wait to receive a low-latency interrupt frame transmits an Emergency Request Action Frame shown in Fig. 10(a) to the AP 101. This frame includes a Category field 1001, a UHR Action field 1002, and an Emergency Request field 1003. The Category field 1001 is a field that indicates that the Emergency Request Action Frame is a UHR Action Frame. For example, the value "38" is stored.

[0098] The type of action frame is stored in the UHR Action field 1002. For example, to indicate that the frame is a request for data reception by an interrupt scheme for low latency data, the value stored is "0."

[0099] The Emergency Request field stores information indicating whether the device wishes to transition to a state in which it waits to receive an interrupt frame of low-latency data, or to a state in which it does not wait. For example, storing "1" in the field indicates that the device wishes to transition to a state in which it waits to receive an interrupt frame of low-latency data. Also, storing "0" in the field indicates that the device wishes to transition to a state in which it does not wait to receive an interrupt frame of low-latency data.

[0100] The AP 101 that receives the frame shown in Fig. 10(a) transmits an Emergency Response Action Frame shown in Fig. 10(b) as a response. This frame includes a Category field 1001, a UHR Action field 1002, and a Status Code field 1004. The value stored in the Category field 1001 is the same as that of an Emergency Request Action Frame. For example, "1" is stored in the UHR Action field 1002 to indicate that this frame is an Emergency Response Action Frame.

[0101] Status Code field 1004 indicates whether or not to accept a request from STA 103. For example, if the request is accepted, AP 101 stores "0" as the value of this field. If the request cannot be accepted for some reason, a value other than "0" is stored as the value of this field. Based on the value of field 1004, the STA that received the Emergency Response Action Frame transitions to a state in which it waits for a low latency frame or a state in which it does not wait for a low latency frame.

[0102] A STA that wishes to receive data using the low-latency data interrupt scheme performs these advance negotiations at a timing prior to S807 in FIG.

[0103] In this embodiment, the request is transmitted from the STA 103 to the AP 101, but the direction of the negotiation may be reversed. In other words, the embodiment may be modified so that the AP 101 transmits a request to the subordinate STA, and the subordinate STA transmits a response. By performing the control described in the second embodiment, for example, the STA can declare to the AP 101 that it will not wait to receive an interrupt frame when it wishes to suppress power consumption due to low battery power or when an energy saving mode is set by the user.

[0104] The control unit 304 of the AP 101 that conducted the negotiation manages, based on the result of the negotiation with the STA, status information indicating whether the STA is in a state of waiting to receive an interrupt frame of low latency data, in association with the STA's information.

[0105] The state information can be used to identify whether or not the STA can perform interrupt reception of the frame described in S404 to S406 in Fig. 4. In this case, AP101 may perform control so as to regard the STA associated with state information indicating that the STA is in a state of waiting to receive an interrupt frame of low latency data as the STA that can perform interrupt reception. In other words, even if low latency data to be transmitted to the STA associated with state information indicating that the STA is not in a waiting state occurs, an interrupt to the STA can be prevented.

[0106] <Variation 1> In the above embodiment, an example has been described in which one MAC frame of STA 103 is included in the A-MPDU from AP 101 to STA 102, but the present invention is not limited to this. For example, in addition to the MAC frame for the STA that is the main destination, interrupt frames for two or more different STAs can be bundled into the A-MPDU. MAC frames with the same destination but different TIDs (Traffic Identifiers) or ACs (Access Categories) and different sequence numbers may be bundled. Also, the MAC frame targeted for interruption directed to a specific STA may be multiple MAC frames.

[0107] Furthermore, the interruption technique described in the above embodiment can also be applied to the transmission of an A-MPDU that a STA transmits to the AP 101. In this case, it is possible to interrupt the A-MPDU when the STA transmits data to the AP 101 with a MAC frame including low latency data that the STA wishes to transmit to another STA and transmit the A-MPDU.

[0108] <Variation 2> In the above embodiment, the case where the capability information is indicated by one bit in the Element 600 shown in FIG. 6 is exemplified, but it can be modified to perform more detailed capability notification. Specifically, it can be configured to indicate the presence or absence of a first capability supporting interrupted reception and the presence or absence of a second capability supporting interrupted reception by different bits. In this case, the first capability indicates the presence or absence of the capability supporting interrupted reception, which receives an A-MPDU including an interrupt frame as a main destination, discards the interrupt frame appropriately, and receives a frame addressed to itself. On the other hand, the second capability may indicate the presence or absence of the capability supporting interrupted reception, which sniffs and interprets an A-MPDU transmitted to another main transmission destination, and appropriately receives an interrupt frame addressed to itself. In this case, the AP 101 manages the detailed capability by linking it as information of the connected STA. Then, the information is utilized to select a main destination to be interrupted and a destination to be interrupted.

[0109] <Variation 3> In the first embodiment, the PHY preamble is configured to notify information indicating whether or not a data interrupt is suggested, but this notification can also be omitted. In this case, a STA in a standby state waiting for an interrupt frame interprets the data portion of all PPDUs received from the AP 101. Then, it determines whether or not a MAC frame addressed to itself is included, and selects and decodes the frame addressed to itself.

[0110] <Modification 4> In the first embodiment, it has been described that the PPDU is indicated as a PPDU for which an interrupt may occur by setting "3" in the PPDU Type and Compression Mode field 713. In this case, it is possible to modify the method so that the AP 101 clearly identifies the STA that should wait for reception and notifies it in the PHY preamble.

[0111] The modified example will be described with reference to FIG. 11. FIG. 11 is a diagram for explaining the field values ​​stored in the U-SIG of the PHY preamble and the characteristics of the PPDU when the field values ​​are set. In this figure, the case of downlink is excerpted and illustrated. When "0" is set in the UL / DL field 710 and "0 to 2" is set in the PPDU Type and Compression Mode field 713, the characteristics of the PPDU are the same as those of the EHT PPDU. Setting "0" in the field 713 of the downlink PPDU means that the PPDU is for DL ​​OFDMA (MU-MIMO technology can also be applied). In this case, it is possible to include a field for allocating RUs to realize OFDMA and one or more user fields in the UHR-SIG. Setting "1" in the field 713 of the downlink PPDU means that the PPDU is a PPDU for communication for a single user or a PPDU for sounding. In this case, the field for allocating RUs to realize OFDMA is omitted in the UHR-SIG. Also, a user field of 0 or 1 is included. Setting "2" in the field 713 of the downlink PPDU means that the PPDU is a non-OFDMA and MU-MIMO PPDU. In this case, the field for RU allocation to realize OFDMA is omitted in the UHR-SIG. Also, to specify two or more terminals that are targets of MU-MIMO, two or more user fields are included.

[0112] In this modification, setting "3" in the field 713 of the downlink PPDU is defined as a PPDU for communication for a single user in which an interrupt may occur. In this case, the field for allocating RUs to realize OFDMA is omitted in the UHR-SIG. In this case, two or more user fields are included in the UHR-SIG.

[0113] In this case, the first user field in the U-SIG is configured to store the STA-ID of the main transmission destination to be interrupted, and the subsequent second and subsequent user fields are configured to store the STA-IDs of the receiving candidate destinations that should wait for the reception of the interrupt frame.

[0114] A brief description will be given of control in the case where this modified example is applied. AP101 estimates STAs that are highly likely to generate low latency data based on time-series data such as past communication results for each STA, communication parameters with the STA, and the like. The estimation may be an estimation using a machine-learned model obtained by pre-learning. When generating a PHY preamble in S403, AP101 generates a PHY preamble in which the STA-IDs of one or more STAs that are estimated to be highly likely to generate low latency data are stored in the second user field and subsequent fields. This process makes it possible to explicitly present STAs that should wait for reception in the PHY preamble. Meanwhile, STAs such as STA102 and STA103 analyze the PHY preamble of the received PPDU in S502 and determine whether an interrupt is suggested. Specifically, the STAs determine that an interrupt is suggested when "0" is set in the UL / DL field 710 and "3" is set in the PPDU Type And Compression Mode field 713.

[0115] In addition, the STA performs the following reception determination instead of the reception determination of S503 to S504 performed after determining that an interrupt is suggested. First, the STA determines whether its own STA-ID is specified in the first user field of the U-SIG. If it determines that its own STA-ID is specified in the first user field of the U-SIG, the process proceeds to S511. If it determines that its own STA-ID is not specified in the first user field of the UHR-SIG, the process proceeds to determining whether interrupt reception waiting is necessary. In determining whether interrupt reception waiting is necessary, the STA determines whether interrupt waiting is necessary based on whether its own STA-ID is specified in the second user field or later of the UHR-SIG. If its own STA-ID is specified in the second user field or later of the UHR-SIG, the STA determines that interrupt waiting is necessary, and proceeds to S505. On the other hand, if the STA's own STA-ID is not specified in the second user field or later of the UHR-SIG, the STA determines that interrupt waiting is unnecessary, and proceeds to S509. By modifying as described above, it becomes possible to perform frame interrupt control after clearly identifying the STA that should wait to receive low latency data.

[0116] (Other embodiment 1) The disclosure of this embodiment also includes the following configuration.

[0117] (Configuration 1) a transmission control means for generating and transmitting an A-MPDU (Aggregation-MAC Protocol Data Unit) that is a bundle of a plurality of MAC frames, each including a MAC (Media Access Control) header and a payload; The communication device is characterized in that the transmission control means controls, when certain conditions are satisfied, to bundle and transmit multiple MAC frames intended for multiple different destinations, including at least a first MAC frame intended for a first destination and a second MAC frame intended for a second destination, into a single A-MPDU.

[0118] (Configuration 2) The communication device described in configuration 1, characterized in that the preamble of the A-MPDU including the first MAC frame and the second MAC frame includes information indicating that different MAC frames intended for multiple destinations can be bundled into the A-MPDU.

[0119] (Configuration 3) The communication device according to configuration 1 or 2, further comprising a determination means for determining an MCS (Modulation and Coding Scheme) of a data portion when a first MAC frame addressed to a first destination and a second MAC frame addressed to a second destination are bundled and transmitted for the A-MPDU.

[0120] (Configuration 4) the communication device is an access point device, a management means for managing station devices connected to the access point device, the management means manages each of the connected station devices by distinguishing whether or not each station device has the capability of accepting interrupt reception of low latency data; the specific condition being that low latency data for a station device having the capability is stored; The communication device described in any one of configurations 1 to 3, characterized in that when the low latency data is stored, the transmission control means controls an A-MPDU that is transmitting or preparing to transmit a MAC frame intended for another station device, the MAC frame being addressed to the station device having the capability and conveying the stored low latency data, to be transmitted in an interrupt manner, thereby bundling and transmitting multiple MAC frames intended for multiple different destinations into a single A-MPDU.

[0121] (Configuration 5) 1. A communication device, comprising: A reception control means for receiving an A-MPDU (Aggregation-MAC Protocol Data Unit); and an interpretation means for judging whether a MAC (Media Access Control) frame constituting the A-MPDU is a MAC frame addressed to the communication device, and decoding a MAC frame determined to be a MAC frame addressed to the communication device, The communication device is characterized in that the interpretation means controls the frame body of a MAC frame that is determined to be destined for a communication device other than the communication device, among the MAC frames that constitute the A-MPDU, so that it is not subjected to decoding.

[0122] (Configuration 6) The communication device according to configuration 5, characterized in that the communication device controls so as not to decode the frame body of the MAC frame determined to be destined for the other communication device by discarding it without decoding it.

[0123] (Configuration 7) A method for controlling a communication device, comprising: a transmission control step of generating and transmitting an A-MPDU (Aggregation-MAC Protocol Data Unit) in which a plurality of MAC frames each including a Media Access Control (MAC) header and a payload are bundled; A control method characterized in that, in the transmission control process, when certain conditions are satisfied, transmission control is performed so that a plurality of MAC frames intended for a plurality of different destinations, including at least a first MAC frame intended for a first destination and a second MAC frame intended for a second destination, are bundled into a single A-MPDU and transmitted.

[0124] (Configuration 8) A method for controlling a communication device, comprising: a reception control step of receiving an A-MPDU (Aggregation-MAC Protocol Data Unit); an interpretation step of determining whether a Media Access Control (MAC) frame constituting the A-MPDU is a MAC frame addressed to the communication device, and decoding the MAC frame determined to be a MAC frame addressed to the communication device; A control method characterized in that, in the interpretation process, control is performed so that the frame body of a MAC frame that is determined to be destined for a communication device other than the communication device, among the MAC frames that constitute the A-MPDU, is not subject to decoding.

[0125] (Configuration 9) A program for causing a computer to execute the method for controlling a communication device according to configuration 7 or 8.

[0126] <Other embodiment 2> The present invention can also be realized by a process in which a program for implementing one or more of the functions of the above-described embodiments is supplied to a system or device via a network or a storage medium, and one or more processors in a 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 implements one or more of the functions.

[0127] The invention is not limited to the above-described embodiments, and various modifications and variations are possible 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]

[0128] 101 AP 102 STA 103 STA 202 Control section 206 Communications Department

Claims

1. It has a transmission control means that generates and transmits an A-MPDU (Aggregate-MAC Protocol Data Unit) which bundles multiple MAC frames containing a MAC (Media Access Control) header and payload, The communication device is characterized in that, when certain conditions are met, the transmission control means controls the transmission of a plurality of MAC frames destined for a plurality of different destinations, including at least a first MAC frame destined for a first destination and a second MAC frame destined for a second destination, bundled into a single A-MPDU.

2. The communication device according to claim 1, characterized in that the preamble of the A-MPDU, which includes the first MAC frame and the second MAC frame, includes information indicating that multiple different MAC frames destined for multiple destinations can be bundled into the A-MPDU.

3. The communication device according to claim 1, further comprising determination means for determining the MCS (Modulation and Coding Scheme) of the data portion when a first MAC frame directed to a first destination and a second MAC frame directed to a second destination are bundled and transmitted to the A-MPDU.

4. The aforementioned communication device is an access point device, The access point device has a management means for managing station devices connected to it, The management means manages each connected station device by distinguishing whether or not it has the capability to accept interrupt reception of low-latency data. The aforementioned specific condition is that low-latency data is stored for the station device having the aforementioned capability. The communication device according to any one of claims 1 to 3, characterized in that when the low-latency data is stored, the transmission control means controls the A-MPDU to transmit a MAC frame destined for a station device having the capability, including a MAC frame that transmits the stored low-latency data, thereby bundling and transmitting multiple MAC frames destined for multiple different destinations into a single A-MPDU.

5. A communication device, A receiving control means for receiving A-MPDU (Aggregate-MAC Protocol Data Unit), The A-MPDU comprises interpretation means for determining whether a MAC (Media Access Control) frame constituting the A-MPDU is a MAC frame destined for the communication device, and for decoding MAC frames that are determined to be destined for the communication device. The interpretation means is characterized by controlling the communication device so that the frame body of a MAC frame that constitutes the A-MPDU and is determined to be destined for a communication device other than the communication device is not subject to decoding.

6. The communication device according to claim 5, characterized in that it controls the device so as not to be decoded by discarding the frame body of a MAC frame that is determined to be destined for the aforementioned other communication device without decoding it.

7. A method for controlling a communication device, The system includes a transmission control process that generates and transmits an A-MPDU (Aggregate-MAC Protocol Data Unit), which is a bundle of multiple MAC frames containing a MAC (Media Access Control) header and payload. The control method is characterized in that, in the transmission control step, when certain conditions are met, transmission control is performed to bundle a plurality of MAC frames destined for a plurality of different destinations, including at least a first MAC frame destined for a first destination and a second MAC frame destined for a second destination, into a single A-MPDU and transmit them.

8. A method for controlling a communication device, A receiving control process for receiving A-MPDU (Aggregate-MAC Protocol Data Unit), The A-MPDU comprises an interpretation step of determining whether a MAC (Media Access Control) frame is destined for the communication device, and decoding the MAC frame that is determined to be destined for the communication device. The control method is characterized in that, in the interpretation step, control is performed so as not to decode the frame body of a MAC frame that is determined to be destined for a communication device other than the communication device, among the MAC frames constituting the A-MPDU.

9. A program for causing a computer to execute the control method of a communication device according to claim 7 or 8.

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