Communication device, control method, and program

Abstract

In order to suppress an amount of power consumption during communication standby compared to an amount of power consumption during communication standby in a first mode, a communication device that performs wireless communication conforming to the IEEE 802.11 standard series transmits, to another communication device, a frame including an information element in which information indicating whether or not a second mode for communication standby in a state where at least two conditions among the number of communication links, a bandwidth, and a spatial stream are changed to conditions in which the amount of power consumption is estimated to be less than in the first mode is supported, and transmits, to the other communication device, enabling or disabling of the second mode using an A-Control field of a MAC header of a data frame.

Description

Communication device, control method, and program

[0001] The present invention relates to a communication device that communicates data.

[0002] In recent years, with the increase in the amount of data to be communicated, the development of communication technologies such as wireless LAN (Local Area Network) has been promoted. As the main communication standards for wireless LAN, the IEEE (Institute of Electrical and Electronics Engineers) 802.11 standard series is known. The IEEE 802.·11 standard series includes standards such as IEEE 802.11a / b / g / n / ac / ax.

[0003] Technologies that utilize sleep or intermittent operation to reduce the power consumption of communication devices have also been studied. For example, in Patent Document 1, a procedure for realizing power saving is shown by indicating and coordinating the wake-up times of devices in advance between an AP (Access Point) and a STA (Station), performing communication at the wake-up times, and suppressing power consumption at other times.

[0004] Also, the standardization of the IEEE 802.11be standard, which is a successor standard to IEEE 802.11ax, is progressing. Furthermore, in the UHR (Ultra High Reliability) task group, the specification of the IEEE 802.11bn standard, which is a successor standard to the IEEE 802.11be standard, is also being studied.

[0005] Japanese Patent Application Publication No. 2016-511600

[0006] Incidentally, the 802.11be standard attempts to improve communication rates compared to previous standards. It also attempts to incorporate Multi-Link Operation functionality, which uses multiple communication links for high-speed and redundant data transmission. Communication devices using new functions such as Multi-Link Operation may receive data with multiple links, multiple spatial stream counts, wide bandwidth, and high MCS (Modulation and Coding Scheme). Therefore, generally, even in idle states waiting for reception, it is necessary to control the signal receiving circuit and antenna so that all signal patterns can be received. These flagship new functions of the standard are certainly useful in terms of faster and more reliable communication and contribute to an improved user experience. However, there is a problem in that the power required to properly operate the communication device increases not only during communication but also when waiting for communication. Thus, in modern communication devices, even the standby power consumption when waiting for communication, such as when waiting for reception, has become a level that cannot be ignored.

[0007] The present invention has been made in view of at least one of the above-mentioned problems. One aspect of the present invention aims to provide a concrete mechanism for more actively reducing standby power consumption. Specifically, it provides a new function that actively reduces standby power consumption by switching between an operating mode customized for power saving with multiple communication conditions such as a small number of links, a small number of streams, and low MCS, and a normal operating mode. Hereafter, for the purpose of explanation, this new function will also be called the DPS (Dynamic Power Saving) function. Another aspect of the present invention aims to provide a mechanism that allows the DPS function to be properly operated by enabling or disabling it using the A-Control field of the data frame.

[0008] One aspect of the present invention is a communication device that performs wireless communication in accordance with the IEEE 802.11 standard series, and has a transmission control means that controls the transmission of a frame to another communication device that includes an information element that stores information indicating whether it supports a second mode in which it waits for communication with at least two or more conditions among the number of communication links, bandwidth, and spatial streams changed to conditions that are estimated to consume less power than the first mode, in order to suppress the amount of power consumed when waiting for communication compared to the power consumption when waiting for communication in the first mode, and the transmission control means further controls the transmission of the enable or disable of the second mode to the other communication device using the A-Control field of the MAC header of a data frame different from the frame.

[0009] According to one aspect of the present invention, a mechanism can be provided to more actively reduce power consumption during standby. According to another aspect of the present invention, the above mechanism can be enabled or disabled by communicating this using the A-Control field of the data frame, thereby enabling proper operation of the function.

[0010] This is a diagram showing an example of the configuration of a communication system. This is a diagram showing an example of the hardware configuration of a communication device (AP / STA). This is a diagram showing an example of the functional configuration of a communication device (AP / STA). This is a sequence diagram showing the procedure of the DPS (Dynamic Power Saving) function. This is an example of an information element for notifying whether DPS is supported. This is an example of an information element for notifying DPS operation information. This is an example of a frame when operation information is notified using an action frame. This is an example of a frame when operation information is notified using the A-Control field. This is an example of an ICF and a response to an ICF. This is an example of an ICF and a response to an ICF. This is a flowchart showing an example of STA control. This is a flowchart showing an example of AP control. This is a flowchart showing an example of STA control. This is a transition diagram of operating modes and operating states to explain the DPS function.

[0011] The embodiments will be described in detail below with reference to the attached drawings. Note that the following embodiments do not limit the invention as defined in the claims. While the embodiments describe multiple features, not all of these features are essential to the invention, and the features may be combined in any way. Furthermore, in the attached drawings, identical or similar configurations are given the same reference numerals, and redundant descriptions are omitted.

[0012] <First Embodiment> Figure 1 shows an example of the configuration of the communication system of this embodiment. The communication system of this embodiment is composed of one access point device (hereinafter simply referred to as AP, AP STA, or access point) and one station device (hereinafter simply referred to as STA, Non-AP STA, or station).

[0013] AP101 and STA102 are successor standards to the IEEE 802.11be standard, which targets a maximum transmission speed of 46.08 Gbps, and are configured to enable wireless frame communication compliant with the IEEE 802.11bn standard.

[0014] IEEE stands for Institute of Electrical and Electronics Engineers. IEEE 802.11bn, the successor standard to IEEE 802.11be, primarily features high-reliability communication, low-latency communication, and improved throughput during congestion. Furthermore, 802.11bn aims to reduce power consumption at access points (APs). The wireless frames used in this successor standard are also called UHR (Ultra High Reliability) PPDUs. PPDU stands for Physical Layer Protocol Data Unit.

[0015] The name UHR was adopted for convenience, taking into account the goals to be achieved in the successor standard and the key features of that standard, and may be renamed once the standard is finalized. Similarly, the name IEEE 802.11bn may be renamed once the standard is finalized. On the other hand, it should be noted that this specification and the attached claims are essentially applicable to all successor standards that are successors to the 802.11be standard. In addition, AP101 and STA102 can also transmit wireless frames corresponding to legacy standards that precede the IEEE 802.11bn standard. Legacy standards include, for example, the IEEE 802.11a / b / g / n / ac / ax / be standards.

[0016] AP101 and STA102 communicate by exchanging wireless signals in frequency bands such as the 2.4 GHz, 3.6 GHz, 5 GHz, 6 GHz bands, and millimeter wave bands such as the 45 GHz and 60 GHz bands. However, the frequency bands used by AP101 and STA102 are not limited to these, and may include, for example, the Sub1 GHz band. Furthermore, AP101 and STA102 can communicate using bandwidths of 20 MHz, 40 MHz, 80 MHz, 160 MHz, 320 MHz, 540 MHz, 640 MHz, 1080 MHz, and 2160 MHz. The bandwidths used by communication devices such as AP101 and STA102 are not limited to these, and may include, for example, 240 MHz or 4 MHz. The IEEE 802.11 series standard specifies frequency channels using a 20 MHz bandwidth as basic channels in frequency bands such as the 2.4 GHz, 5 GHz, and 6 GHz bands. Furthermore, this standard defines multiple available channels in each of the 2.4 GHz, 5 GHz, and 6 GHz bands. This standard also allows the use of one channel in combination with other adjacent channels. In this embodiment, the use of one channel in combination with other adjacent channels is referred to as channel bonding. A bundle of channels formed by one or two or more adjacent channels is referred to as a communication link (link). That is, one link formed by combining two channels with a 20 MHz bandwidth uses a 40 MHz bandwidth. AP101 is an access point that supports multiband functionality, providing a network on multiple different frequency channels. In this embodiment, AP101 is exemplified as a dual-band access point providing a 2.4 GHz band network and a 5 GHz band network.

[0017] STA102 establishes one or more links between itself and AP101 in order to communicate data with AP101 and other communication devices. For example, STA102 performs a connection procedure with AP101 to establish a link with AP101. Once the connection procedure is completed between STA102 and AP101, a link is established between the devices. With the link established, communication devices such as AP101 and STA102 can access the wireless medium and communicate data and other information with the other communication device.

[0018] Furthermore, AP101 and STA102 in this embodiment can establish multiple links between devices and perform Multi-Link communication. Hereafter, a communication link will also be simply referred to as a link. Hereafter, Multi-Link communication will also be referred to as MLO (Multi-Link Operation). AP101 that performs Multi-Link communication will also be referred to as AP MLD (AP Multi-Link Device) 101, and STA102 that performs Multi-Link communication will also be referred to as non-AP MLD 102. For example, AP101 can establish a link with STA102 in a 2.4GHz band network and communicate. In addition, AP101 and STA102 can establish a second link in the 5GHz band, for example, in parallel with this, and communicate. In this case, STA102 performs Multi-Link communication, utilizing two links for communication. STA102 can perform STR (Simultaneous Transmit and Receive) operation with AP101, allowing simultaneous transmission on link 2 while receiving on link 1. STA102 can also perform Nonsimultaneous Transmit and Receive (NSTR) operation with AP101, which has the constraint of using all links simultaneously for transmission or simultaneous reception. NSTR operation is used when the frequency distance between links is short and mutual interference occurs. Communication using two communication links in STR operation is also called STR communication.

[0019] For example, if two links are established between devices, Link 1 using a 160 MHz bandwidth and Link 2 using an 80 MHz bandwidth, communication devices such as AP101 and STA102 will communicate using the channels that make up these links. The link using the 160 MHz bandwidth is composed of eight channels with a bandwidth of 20 MHz each. The link using the 80 MHz bandwidth is composed of four channels with a bandwidth of 20 MHz each.

[0020] Furthermore, AP101 and STA102 can communicate using multiple spatial streams to communicate more efficiently with other communication devices. Specifically, they can perform SU-MIMO (Single User Multi Input Multi Output) communication with 1SS, 2SS, and 4SS. They can also perform MU-MIMO (Multi User Multi Input Multi Output) communication with 2SS to 16SS. In SU-MIMO and MU-MIMO communication, the actual communication rate can be increased in proportion to the number of streams. In addition, multiple spatial streams can be used for increased reliability. Furthermore, to transmit information at a higher density through modulation, communication can be conducted using BPSK, QPSK, 16QAM, 64QAM, 256QAM, 1024QAM, 4KQAM, etc. MCS (Modulation and Coding Scheme) is an indicator that shows the combination of modulation method and modulation scheme such as code rate, and communication devices such as AP101 and STA102 can select one of the MCS from MCS0 to MCS15 to communicate.

[0021] As described above, communication devices such as the STA102 use the aforementioned MLO function to communicate via multiple links and receive data with the aforementioned multiple spatial streams, wide bandwidth, and high MCS (Modulation and Coding Scheme). Therefore, generally, even in the idle state waiting to receive, it is necessary to control the signal receiving circuit and antenna so that all signal patterns can be received. Utilizing these functions is certainly useful in terms of increasing communication speed and reliability, and contributes to improving the user experience. However, there is also the problem that the power required to properly operate the communication device increases not only during communication but also in the idle state waiting to start communication. Thus, in modern communication devices, even the standby power consumption when waiting to receive has reached a level that cannot be ignored.

[0022] In light of this, this embodiment provides a specific mechanism to more actively reduce power consumption during standby. Specifically, a new DPS function is provided that communicates using communication parameters customized for power saving, such as supporting only a small number of links, a small number of streams, and low MCS. The DPS function provides a mechanism to actively reduce power consumption during standby by switching between DPS Enable Mode and the normal operating mode, Active Mode. Hereafter, for the purpose of explanation, this new function will also be referred to as the Dynamic Power Saving function or the DPS function. Furthermore, a mechanism is provided to ensure that the Dynamic Power Saving function can be operated appropriately by allowing prior notification of whether or not to support and enable the Dynamic Power Saving function. DPS Enable Mode may also be called DPS Enabling Mode.

[0023] First, the concept of the DPS function will be explained using Figure 13. Figure 13 shows a transition diagram of the operating modes of the communication device to explain the DPS function. Communication devices such as AP101 and STA102 support Active Mode, which corresponds to normal operation, and DPS Enabled Mode, in which the DPS function, which actively reduces power consumption during standby, is enabled. Communication devices such as AP101 and STA102 operate in one of several operating modes, which include at least the two operating modes described above. In this embodiment, Active Mode is also called DPS Disabled Mode or DPS Disabled State. Active Mode can also be described as a normal mode in which communication can be performed under normal communication conditions agreed upon between the AP and STA. Communication devices such as the STA102 operating in this Active mode can communicate with the AP101 using Multi-Link communication, communication using multiple streams, communication using wide bandwidths such as 80 MHz, 160 MHz, and 320 MHz, and communication using high MCS. When switching operating modes, the communication device such as the STA102 notifies the opposing device such as the AP101 that the mode has been switched. This notification can use an Action frame or a data frame containing an A-Control field.

[0024] Communication devices such as STA102 that have transitioned to DPS Enable Mode operate in either NPCS or DPSCS. NPCS stands for Normal Power Communication State, and DPSCS stands for Dynamic Power Saving Communication State. Communication devices such as STA102 operating in the NPCS operating state can perform high-speed and / or highly reliable communication under normal communication conditions agreed upon between the AP and STA, similar to Active Mode. STA102 transitions its operating state to DPSCS when a predetermined time has elapsed since data communication with the outside has ended, or when it has communicated a frame indicating the intention to terminate communication, such as CF-End, which signals the end of the transmission opportunity. DPSCS is an operating state that is expected to reduce power consumption. When transitioning to the DPSCS operating state, communication devices such as STA102 switch their operating settings to customized communication conditions to reduce power consumption related to waiting for communication, such as one link, one spatial stream, a 20 MHz bandwidth, and low MCS. Due to its characteristic of being able to maintain a state in which bidirectional communication is possible with low power consumption, in this embodiment, the state in which bidirectional communication is being performed / can be performed in DPSCS is also called the Low Power Awake state. In other words, the Low Power Awake state can be said to be a state in which bidirectional communication is being performed / can be performed with lower power consumption than the state in which bidirectional communication is being performed / can be performed in Active mode or the NPCS operating state. In addition, in this embodiment, the communication conditions with constraints when operating in DPSCS are also called LowCapability. Furthermore, the normal communication conditions when operating in Active Mode or DPS-Enabled Mode NPCS are also referred to as High Capability.

[0025] A communication device such as STA102, operating in the DPSCS operating state, will revert its operating state back to NPCS upon receiving a frame indicating its own desire or a request from the opposing communication device, such as AP101, to communicate in a normal state.

[0026] Thus, communication devices such as the STA102 operating in DPS-Enabled Mode utilize NPCS and DPSCS as their operating states. For example, during normal operation, it transitions to NPCS to enable high-speed communication, and during standby, it transitions to DPSCS to reduce power consumption. By utilizing these operating states, the STA operating in DPS-Enabled Mode can achieve both convenience and power saving.

[0027] In Figure 13, two modes, Active Mode and DPS Enable Mode, are shown as examples of multiple operating modes, but the device is not limited to these. Naturally, communication devices such as STA102 can also support operation in other operating modes, such as the conventionally known Scheduled PS mode and Unscheduled PS mode. Communication devices such as STA102 operating in Scheduled PS mode or Unscheduled PS mode have a long period of Doze state and are only in the Awake state during the period when a DTIM is transmitted to monitor the presence of uplink data. During the period of operation in PS mode, communication devices such as STA102 maintain a Doze state for almost the entire duration, except for extremely short periods of Awake state. During this Doze state, communication devices such as STA102 stop supplying power to the communication circuit. By performing these controls, the average power consumption of the communication device during the period in which it operates in the PS mode can be reduced. Furthermore, the Low Power Awake state may be used as the Awake state in these PS modes. Communication devices such as the STA102 operating in these PS modes transition to either DPS Enable Mode or Active Mode based on their own preference or the DTIM reception status. The choice of which operating mode to transition to can be determined based on past communication performance, etc. By appropriately switching between multiple operating modes according to the communication status, power consumption can be reduced. Other operating modes may include EMLSR (Enhanced Multi-Link Single Radio) mode, etc.

[0028] In summary, the DPS-Enabled Mode of this embodiment, which enables the DPS function, can be described as a mode with lower average power consumption compared to Active Mode (a mode designed to suppress power consumption). Furthermore, while the DPS-Enabled Mode has higher average power consumption compared to Scheduled / Unscheduled PS Mode, it can be described as a mode that offers greater communication convenience, such as the ability to perform small-data communication at any time.

[0029] The specific mechanism for switching between the above modes will be explained in detail using Figures 2 and onward. Note that Figure 1 shows a communication system consisting of one AP101 and one STA102 as an example, but the number of STAs constituting the communication system may be greater than shown. Furthermore, STAs that only support the legacy standard and do not support the DPS function can also be connected to the AP101 network to constitute the communication system.

[0030] Furthermore, AP101 and STA102 can be configured to support wireless communication based on other communication standards such as Bluetooth®, NFC, and Bluetooth® LE (Low Energy). NFC stands for Near Field Communication. AP101 and STA102 can also be configured to support wired communication using Ethernet® cables or wired communication using optical fibers. Specific examples of AP101 include, but are not limited to, wireless LAN routers and personal computers (PCs). AP101 and STA102 may also be information processing devices such as wireless chips that support the transmission and reception of UHR PPDUs. In this case, they can be configured to perform various controls using hardware circuits within the wireless chip. It is also possible to configure the wireless chip to perform various processes through the cooperation of a processor such as an ASIP, memory, and hardware circuits within the wireless chip. ASIP stands for Application-specific instruction set processor.

[0031] Specific examples of STA102 include cameras, printers, tablets, smartphones, projectors, PCs, gaming devices, video cameras, smart glasses, and wearable devices such as head-mounted displays. Other examples include IoT devices such as sensor nodes and network video cameras, but these are not the only examples.

[0032] <Hardware Configuration of Communication Device> Figure 2 shows an example of the hardware configuration of a communication device (AP101, STA102). As an example of its hardware configuration, the communication device includes 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.

[0033] The memory unit 201 is composed of both ROM and RAM, or either one, and stores various information such as programs for performing various operations described later, and communication parameters for wireless communication. RAM stands for Random Access Memory, and ROM stands for Read Only Memory. In addition to memory such as ROM and RAM, storage media such as hard disks and non-volatile storage devices such as SSDs (Solid State Drives) may be used as the memory unit 201.

[0034] The control unit 202 is composed of, 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 abbreviation for Central Processing Unit, and MPU is an abbreviation for Micro Processing Unit. The control unit 202 controls the entire device by executing the program stored in the memory unit 201 and operating hardware circuits such as the ASIC. Alternatively, the control unit 202 may control the entire device in cooperation with the OS (Operating System) and the program stored in the memory unit 201.

[0035] Furthermore, the control unit 202 controls the functional unit 203 to perform predetermined processes such as imaging, printing, and projection. The functional unit 203 is hardware that enables the device to perform predetermined processes. For example, if the communication device is a camera such as a digital still camera or a smartphone with a camera, the functional unit 203 is the imaging unit and performs imaging of the surrounding image via a camera unit (not shown) of the communication device. Also, for example, if the communication device is a printer, the functional unit 203 is the printing unit and performs printing on a sheet such as paper based on print data obtained from an external source via wireless communication. Also, for example, if the communication device is a projector or smart glasses, the functional unit 203 is the projection unit and performs projection of image data or video data obtained from an external source via wireless communication. In the case of smart glasses, the projection surface is the end user's retina, etc. The data processed by the functional unit 203 may be data stored in the storage unit 201, or data communicated with other APs or STAs via the communication unit 206, which will be described later. Furthermore, communication devices such as AP101 can also provide network storage functions such as NAS (Network Attached Storage). This function is provided to other communication devices as a web service such as a network storage service. For example, a communication device such as STA connects to the network storage service provided by AP101 using a protocol such as SMB over QUIC. Then, the communication device such as STA uploads files to the storage service and downloads files from the storage. This upload and download data communication is also achieved by communicating UHR PPDUs between devices.

[0036] The input unit 204 receives various operations from the user. The output unit 205 provides various outputs to the user. Here, the output from the output unit 205 includes, for example, at least one of the following: display on the screen, audio output from a speaker, or vibration output. Note that both the input unit 204 and the output unit 205 may be implemented in a single module, such as a touch panel.

[0037] The output unit 205 functions as a display means for presenting information to the user. The input unit functions as a reception means for receiving user input.

[0038] The communication unit 206 controls wireless communication compliant with the IEEE 802.11 standard series and IP communication. In this embodiment, the communication unit 206 can work in cooperation with the antenna 207 to perform communication control to send and receive UHR PPDUs, which are wireless frames of the UHR standard, and PPDUs corresponding to earlier standards. The multiple antennas 207 are, for example, antennas capable of sending and receiving signals in at least one of the following frequency bands: sub-GHz band, 2.4GHz band, 5GHz band, 6GHz band, and millimeter wave band. Figure 2 illustrates a case where AP101 and STA102 in this embodiment have three antennas, but it is not limited to this, and there may be more or fewer.

[0039] Furthermore, if the communication device supports the aforementioned NFC standard, Bluetooth standard, wired communication standard, etc., the communication unit 206 should be configured to control wireless or wired communication in accordance with these communication standards. In addition, the communication units 206 of AP101 and STA102 have hardware circuits for decoding and encoding signals communicated on each link. Each antenna and hardware circuit is configured to allow for individual power control. It is also possible to configure the system to have separate communication units corresponding to each link.

[0040] Next, the functional configuration of AP101 and STA102 will be explained using Figure 3. Communication devices such as AP101 and STA102 have functional units such as a frame processing unit 301, a mode control unit 302, an RXTX control unit 303, and a frame transmission / reception unit 304.

[0041] The mode control unit 302 works in cooperation with each functional unit and hardware to control the aforementioned operating modes and connection with the opposing device. Specifically, the connection process involves Authentication processing, Association processing, 4-way handshake processing, etc., to establish a communication link with the opposing communication device. In the case of AP101, the opposing device is an STA such as STA102, and in the case of STA102, the opposing device is an AP such as AP101. The control unit 302 also manages the communication parameters to be used in each operating mode. When switching operating modes, the control unit 302 uses the managed communication parameters to request the RXTX control unit 303 to switch the communication conditions. Upon receiving the request for switching, the control units 303 and 304 control the communication unit 206 and multiple antennas 207 to switch the communication conditions necessary for transmission and reception.

[0042] The frame processing unit 301 performs signal (frame) generation and analysis processing when communicating with the other party's communication device. The frame processing unit 301 generates management frames for the communication device to execute connection procedures and control frames for controlling communication. The management frames generated and analyzed by the processing unit include Beacon, Probe Request, Probe Response, Association Request, Association Response, FilS (Fast Initial Link Setup) Discovery, and Action. It also includes Authentication Request and Authentication Response frames. It also includes Response Request and Response. The processing unit 301 also generates and analyzes other management frames from the IEEE 802.11 standard series as needed, but due to space limitations, this will not be explained here.

[0043] Also, the control frames generated or analyzed by the processing unit include frames that transition the operation state of the DPS function in a situation where the DPS function is enabled. For example, frames that prompt a counterpart device, such as NPCS (Low Power Communication State) described later, to transition to NPCS (Normal Power Communication State) are also included. For the sake of explanation, this frame is called ICF (Initial Communication Frame). Also, the frames generated or analyzed by the processing unit include ICF Response, which is a response to the ICF. The management frames generated by the frame processing unit 301 are, of course, not limited to these. Also, the frame processing unit 301 generates data frames, QoS data frames, etc. based on instructions from upper applications (not shown). The frame processing unit 301 generates information elements such as UHR Capabilities element and UHR Operation element defined in the IEEE802.11 series standards. Also, it can generate a UHR Protected action frame related to the DPS function. Also, it is possible to transmit the activation or deactivation of the DPS function using the A-Control field, which is the header of the data frame. Details will be described later.

[0044] The UHR Capabilities element can include an information element indicating whether communication devices such as AP101 and STA102 have the ability to execute the DPS function. The UHR Operation element and the elements within the UHR Protected action frame can include information elements for negotiating whether to enable the DPS function. Details of these elements will be described later.

[0045] The frame transmission / reception unit 304 performs the transmission processing of wireless frames generated by the frame processing unit 301 and the reception processing of wireless frames from the receiving device. The received digital data obtained through the reception processing is transferred to the processing unit 301. The processing unit 301 analyzes the received digital data transferred from the transmission / reception unit 304 and, according to the analysis results, performs processing to generate an appropriate response frame or notifies higher layers (not shown) of the analyzed data (such as IP data included in the payload).

[0046] The UI (User Interface) control unit 305 provides a settings screen as a UI for the user to input settings related to communication. The UI control unit 305 also receives user operations on the settings screen via the input unit 204 and stores the settings in the storage unit 201 as the operation settings of the communication device. The UI control unit 305 accepts setting change operations to enable or disable the DPS function via a settings screen (not shown). It also stores the user setting to enable or disable the DPS function corresponding to the setting change operation in the storage unit 201. These operation settings will be referenced as appropriate in the flowchart described later.

[0047] <DPS Execution Procedure> Next, we will explain the procedure for using the DPS function between AP101 and STA102 using Figure 4. Figure 4 is a sequence diagram showing the execution procedure of the DPS (Dynamic Power Saving) function performed between AP101 and STA102.

[0048] First, STA102 performs connection processing for AP101 (F401). The connection processing is described below. AP101 periodically broadcasts information necessary for other communication devices (such as STA102) to connect to it using Beacon frames (Beacon) or FILS Discovery frames (FILS Discovery). By receiving Beacon or FILS Discovery, STA102 recognizes APs such as AP101 in its vicinity and starts the wireless connection procedure. Note that if AP101 does not transmit a Beacon, or if STA102 is unable to properly receive the Beacon transmitted by AP101, STA102 may start the wireless connection procedure without receiving a Beacon. For example, STA102 may initiate a wireless connection procedure using connection information such as an SSID (Service Set Identifier) ​​or passphrase previously registered by the user. To connect to AP101, STA102 first sends a Probe Request frame (Probe Request) to AP101. Upon receiving the Probe Request, AP101 sends a Probe Response frame (Probe Response) addressed to STA102. When connecting via Multi-Link, ML Probe Request and ML Probe Response may be sent and received separately. When STA102 receives a Probe Response, it sends an Authentication frame (Authentication) to AP101. When AP101 receives an Authentication, it sends an Authentication back to STA102. The Authentication may be sent and received twice. When STA102 receives an Authentication, it sends an Association Request frame (Association Request). When AP101 receives an Association Request, it sends an Association Response frame (Association Response).With these procedures, a connection procedure is executed between the AP 101 and the STA 102, and a link using a wireless medium is established between the AP 101 and the STA 102. Note that after the above connection procedure, the AP 101 and the STA 102 may execute a 4-way handshake or the like for exchanging security information. Also, the AP 101 and the STA 102 may execute a wireless connection procedure using a method other than the above.

[0049] The AP 101 and the STA 102 exchange capability information by including an information element indicating the capability information indicating whether or not they support the Dynamic Power Saving mode in at least one frame used in the wireless connection procedure.

[0050] Specifically, in the wireless connection procedure, the AP 101 and the STA 102 share the capability information indicating whether or not they support the Dynamic Power Saving mode with the communication device of the other party. Also, they share information such as the Link and MCS used when executing Dynamic Power Saving with the communication device of the other party. In this embodiment, the information for specifying the optional functions supported by the communication device in wireless communication is called capability information.

[0051] A specific example of the capability information exchanged in the wireless connection procedure will be described using FIG. 5. As an example, the capability information is transmitted to the peer device using the UHR MAC Capabilities element shown in FIG. 5. FIG. 5 is an example of the UHR MAC Capabilities Element included in the frame for performing the wireless connection procedure.

[0052] The UHR MAC Capabilities element is included in the above-mentioned Beacon, Probe Request, Probe Response, Association Request, Association Response, etc. In other words, the UHR MAC Capabilities element is an information element that transmits the capability information indicating whether or not it supports the optional functions of the 802.11bn standard.

[0053] The UHR MAC Capabilities element includes an Element ID field 501, a Length field 502, and an Extended Element ID field 503. The UHR MAC Capability element further includes a DPS (Dynamic Power Saving) Support field 504 and a DPS Assisting Support field 505. It also includes fields indicating whether other optional capability information is supported. For example, it may include a field indicating whether NPCA (Non-Primary Channel Access) is supported.

[0054] The combination of the Element ID field 501 and the Extendec Element ID field 503 indicates the type of element. In this embodiment, as an example, an element with 255 specified in field 501 and 138 specified in field 503 is defined as a UHR Capability element. However, it is not limited to this. Other combinations can also be defined as UHR Capability elements. The Length field 502 indicates the length of the element shown in Figure 5. The DPS (Dynamic Power Saving) Support field 504 stores a value indicating whether the communication device transmitting the frame supports the DPS function. Storing "1" in this field indicates that the communication device transmitting the frame supports the DPS function. Storing "0" in this field indicates that the communication device transmitting the frame does not support the DPS function. Note that "0" can also be modified to mean that the DPS function is not supported or that the function is disabled. The DPS Assisting Support field 505 indicates whether the communication device transmitting the frame has an assist function to send an ICF requesting other communication devices to transition to High Capability. Storing "1" in this field indicates that the communication device transmitting the frame supports the DPS Assisting function. Storing "0" in this field indicates that the communication device transmitting the frame does not support the DPS Assisting function. A DPS AP that supports DPS can also function as a DPS Assisting AP, and "1" is stored in this field. A DPS STA that supports DPS can optionally support the DPS Assisting function.

[0055] Field 504 may also be defined as a field within a field that transmits other sets of capability information.

[0056] AP101 and STA102 enable or disable the DPS function based on capability information indicating whether they support the DPS function, which they notify or acquire from each other, and on the communication status. In other words, they switch their operating mode to Active Mode or to DPS Enabled Mode, as explained using Figure 13.

[0057] In this embodiment, when operating an STA such as STA102 in DPSCS within DPS Enable Mode, it is assumed that one specific link is used to listen for frames from the AP. However, it is not limited to this, and the number of communication links when operating in DPSCS may be multiple. For example, if the number of links when operating in NPCS is 3, it is sufficient to configure it so that the number of links when operating in DPSCS is reduced to 2, compared to the number of links when operating in NPCS. Also, the number of links may be the same when the operating state is DPSCS and when it is NPCS. In that case, when transitioning to DPSCS, the power consumption during standby can be suppressed by customizing two or more other communication conditions such as MCS and spatial stream count for power saving.

[0058] APs such as AP101 can transmit detailed information about the operating parameters that the STA, which operates in DPS-Enabled Mode, should use, to the STA in advance using the UHR Operation element shown in Figure 6.

[0059] Figure 6 shows an example of a UHR Operation element that AP101 includes in the frame used for wireless connection procedures.

[0060] AP101 transmits two or more communication conditions to be used when operating in an operating state such as DPSCS to a rival device such as STA102 by including the element shown in Figure 6 in the frame used for the wireless connection procedure. Specifically, AP101 appropriately determines the link to listen on and the communication parameters to be used in DPSCS when the subordinate STA is operating in DPSCS of the DPS function. Then, it transmits Beacon, Probe Response, and Association Response frames that include the UHR Operation element containing the determined communication parameters. Note that the UHR Operation element may be included in only one of the listed frames. The UHR Operation element may also be included in other frames.

[0061] Figure 6 shows an example of a UHR Operation element. The UHR Operation element includes an Element ID field 601, a Length field 602, and an Extended Element ID field 603. The UHR Operation element also includes a UHR Operation Permeters field, a Basic UHR MCS And Nss Set field, and a UHR Operation Information field 610. The Element ID field 601 and the Extended Element ID field 603 are fields for uniquely identifying the element. Therefore, different values ​​are stored in these fields than in the combination of 501 and 503 shown in Figure 5 above.

[0062] The UHR Operation Permeters field includes the DPS Operation Information Present 605 field and other fields. The DPS Operation Information Present 605 field consists of 1 bit. Storing a 1 in this field means that field 610 contains operational information for DPS operation. Storing a 1 in this field also implicitly communicates to the STA that the AP is operating in DPS Enable Mode. Storing a 0 in this field means that field 610 does not contain operational information for DPS operation. Storing a 0 in this field also implicitly communicates to the STA that the AP is operating in DPS Disabled Mode.

[0063] Next, we will explain field 610. The DPS Operation Information Present field 610 contains various operational information for optional functions newly defined in the IEEE 802.11bn standard. Figure 6 shows an example of operational information when 1 is stored in the DPS Operation Information Present field. When 1 is stored in the DPS Operation Information Present field 610, the DPS Operation Information Present field 610 also includes the DPS Operation Information field 611.

[0064] The DPS Operation Information field 611 contains various operational information that should be used when operating in DPS Enable Mode. Specifically, the MCS field 606 stores the upper limit of the MCS that STA should support when operating in DPSCS. For example, it stores an upper limit indicating that only MCS with a QAM lower than the QAM that can be used when operating in NPCS (e.g., 4096-QAM) (e.g., 16-QAM, 64-QAM, 256-QAM, etc.) will be supported. More specifically, the field can store an index value corresponding to the upper limit of UHR-MCS that is expected to be used when operating in DPSCS. For example, if "7" is stored, the upper limit of the MCS that can be used is 64-QAM with a coding rate of 5 / 6. In other words, if you store "7", the UHR-MCS that becomes available when operating with DPSCS is limited to MCS indicated by an index value between 0 and 6.

[0065] The Listen Link field 607 stores the Link ID indicating which Link should be used for receiving when operating in DPS mode DPSCS. The DPS Padding Delay field 608 indicates the time required when switching from DPSCS to NPCS. The DPS Transition Delay field 609 indicates the time required when switching from NPCS to DPSCS. Alternatively, instead of the Listen Link ID information, the Link IDs of Links that can send and receive frames in DPSCS may be shown as a bitmap in the Link ID Bitmap field. The DPS Operation Information field 611 may also include other communication parameters. For example, it may include parameters such as the number of spatial streams used in DPSCS and the bandwidth to be used.

[0066] Returning to the explanation of Figure 4, the sequence for enabling the DPS function will be described. STA102 sends a frame to AP101 to enable DPS. Upon receiving the frame, AP101 sends a response frame. Upon receiving the response frame, STA102 transitions its operating mode to DPS Enable Mode. In this embodiment, the case where the system transitions to the aforementioned DPSCS operating state in response to the reception of the response frame is illustrated, but the system is not limited to this.

[0067] The frame for enabling DPS will be explained using Figures 7 and 8. Figure 7 shows an example of the Action field of an Action frame that notifies the enabling / disabling of Dynamic Power Saving. In this embodiment, this field is referred to as the Dynamic Power Saving Mode Notification frame Action field. However, it is not limited to this, and this field may be called by other names. This field includes the Category field 701, the Protected UHR Action field 702, the Dialog Token field 703, and the Dynamic Power Saving Control field 704. The Dynamic Power Saving Mode Notification frame Action field may also include the Dynamic Power Saving Parameter Update field 705. The Category field 701 indicates the category of this Action field. For example, the Category field 701 stores an identification number corresponding to a Protected UHR Action. The Protected UHR Action field 702 indicates the identifier of this Action field within the Protected UHR Action category. For example, the Protected UHR Action field 702 stores an identification number that indicates the Dynamic Power Saving Mode Notification frame Action field. The Dialog Token field 703 indicates an identifier for performing a series of information exchanges between AP101 and STA102. For example, the identifier assigned by the requesting communication device is stored in the Dialog Token field 703. The responding communication device stores the value contained in the received Dialog Token field 703 in the Dialog Token field 703 of the response frame and transmits it.

[0068] The Dynamic Power Saving Control field 704 includes the Dynamic Power Saving Mode field 711 and the Dynamic Power Saving Parameter Update Control field 712. The Dynamic Power Saving Mode field 711 indicates the intention to use the DPS function. For example, if STA 102 requests to start using the Dynamic Power Saving function, it stores 1 in this field. On the other hand, if STA 102 requests to stop using the DPS function, it stores 0 in this field.

[0069] The Dynamic Power Saving Parameter Update Control field 712 indicates the presence or absence of the Dynamic Power Saving Parameter Update field 705. For example, if the Dynamic Power Saving Mode Notification frame Action field contains the Dynamic Power Saving Parameter Update field 705, 1 is stored in this field. On the other hand, if the Dynamic Power Saving Parameter Update field 705 is not included, 0 is stored in this field. The Dynamic Power Saving Parameter Update field 705 includes the MCS field 606, the Listen Link ID field 607, the DPS Padding Delay field 608, and the DPS Transaction Delay field 609. These fields serve the same roles as the fields of the same name described in Figure 6, so their explanation is omitted. Also, as in Figure 6, it may include parameters for the number of spatial streams used in DPSCS and the bandwidth to be used. STAs such as STA 102 transmit an Action frame with the Dynamic Power Saving Parameter Update field 705 attached when they want to customize the DPSCS communication parameters.

[0070] AP101 determines whether to use the DPS function based on the frame received from STA102. Specifically, AP101 obtains the value of the DPS Mode field 711 contained in the UHR Protected action frame received from STA102, and determines the intention of the opposing STA, such as STA102, based on this value.

[0071] AP101 responds to STA102 with a response frame that includes a Response field, which adds a Status Code to each field described in Figure 7. STA102 analyzes the Status Code value in the response frame and determines whether AP101 has accepted the request to use the DPS function. If AP101 has accepted the request, STA102 changes its own operating mode to the operating mode corresponding to the request.

[0072] Figure 4 illustrates a case where STA102 requests to use the DPS function and AP101 accepts the request. STA102 updates its own communication parameters to the communication parameters corresponding to DPSCS. Specifically, if STA102 communicates information about updating communication parameters using the Enable sequence frame exemplified in F402, it sets those communication parameters. On the other hand, if it does not communicate information about updating communication parameters using the Enable sequence, STA102 sets itself with the DPSCS communication parameters previously shared by AP101 using the UHR Operation element. Subsequently, STA102 starts the frame waiting process for DPSCS.

[0073] Furthermore, the DPS enable / disable frames can also be configured to be included in the MAC header of the data frame. The case where they are included in the MAC header of the data frame is explained using Figure 8. Figure 8 shows an example of communicating Dynamic Power Saving enable / disable using the A-Control field of the MAC frame. The type field of the Frame Control field 801 stores "10" to indicate that it is a data frame. This data frame includes the HT Control field 802. The first two bits of the HT Control field 802 indicate the type of the HT Control field. Specifically, the first two bits are used to identify whether it is HT / VHT / HE type. If "11" is stored in this value, it includes the A-Control field 812. The A-Control field 812 includes the Control ID field 821 and the Control Information field 822. For example, by storing "10" as the value of the Control ID field 821, it can be indicated that this field can switch between enabling and disabling DPS. "10" representing DPS is just one example; any value greater than or equal to 10 that corresponds to DPS is acceptable. In this case, the subsequent Control Information field 822 stores operational information for DPS. Specifically, it stores the DPS Mode field 831, the Listen Link ID field 832, the DPS Padding Delay field 833, and the DPS Transaction Delay field 834. The DPS Mode field 831 indicates whether DPS is enabled or disabled with one bit. Storing 1 in this field means a request that transitions to DPS Enable Mode. Storing 1 in this field means a request that transitions to DPS Disabled Mode. The Listen Link ID field 832 indicates the Link ID of the Link to be listened to when DPS mode is enabled. The DPS Padding Delay field 833 indicates the time required when DPS switches from disabled to enabled.The DPS Transition Delay field 834 indicates the time required when DPS switches from enabled to disabled. Alternatively, instead of Listen Link ID, the Link ID Bitmap may be used to show the Link IDs of Links that can send and receive frames when DPS is enabled, or after data frame transmission, as a bitmap.

[0074] Finally, the Body 803 stores user data such as the image data and print data mentioned above. By performing the procedure described above, it becomes possible to transmit user data and switch between enabling and disabling DPS within a single wireless frame.

[0075] Next, we will explain the state transition from DPSCS to NPCS. When AP101 determines that data to be sent to STA102 has been generated, AP101 sends an ICF (F403) to STA102 that triggers control to change STA's operating state from DPSCS to NPCS.

[0076] Upon receiving the ICF transmitted by F403, STA102 transmits a response signal to the ICF (F404). Specific examples of the ICF and the response signal to the ICF are explained using Figures 9A and 9B. The ICF frame shown in Figure 9A is a type of Control frame and includes the Frame Control field 901, Duration field 902, RA field 903, TA field 904, and Link Info List field 905. The Frame Control field 901 is a field that identifies the type of frame and contains a value indicating that the frame is an ICF frame for the DPS function. The Duration field 902 indicates the maximum duration of the NPCS initialized by the ICF frame. Upon receiving the ICF frame, STA transitions to a state where it can receive the frame with the parameters specified in the Link Info List field while waiting for reception for the period specified in this field. The RA field 903 stores the MAC address of STA 102, which indicates the frame's recipient. The TA field 904 stores the MAC address of AP 101, which indicates the frame's sender. The Link Info List field 905 stores one or more correspondence pieces of information that combine information identifying the link used in the NPCS state with the communication parameters of that link. When activating multiple links when STA is operated in the NPCS operating state, AP 101 stores multiple correspondence pieces of information in the List field 905. One correspondence piece of information consists of fields 911 to 914. The correspondence piece of information is described in detail. The correspondence piece of information includes the Link ID field 911, BW field 912, NSS field 913, MCS field 914, and Delay field 915. The Link Info List field 905 is information that identifies the link used in NPCS. Furthermore, fields 912 to 915 indicate the communication parameters to be used when communicating on the link specified in 905. Let's explain this in detail. Field 912, BW, indicates the bandwidth to be used for communication.For example, values ​​of 0, 1, 2, 3, and 4 indicate that frames should be listened to or transmitted at 20 MHz, 40 MHz, 80 MHz, 160 MHz, and 320 MHz, respectively. The NSS field 913 indicates the number of spatial streams. For example, it indicates that frames should be listened to or transmitted at spatial streams equal to the value indicated in the field plus 1. The MCS field 914 indicates the maximum MCS used for communication. The ICF frame is to be transmitted in the Link and bandwidth where STA 102, in DPSCS operating state, is waiting for communication. On the other hand, in order to secure transmission rights in different Links that are expected to be used for communication after transitioning to NPCS, the ICF may also be transmitted simultaneously to those different Links.

[0077] Next, the response frame to the ICF will be explained using Figure 9B. Figures 9A and 9B are examples of ICF Response frames. The ICF Response frame may include the Frame Control field 901, Duration field 902, RA field 903, TA field 904, Status Code field 921, and Link Info List field 905. Fields that overlap with those in Figure 9A are assigned the same number and their explanations are omitted. The Status Code field 921 indicates whether communication is possible with the value specified in the ICF. Note that it is also possible to configure the system to omit the transmission of the ICF Response frame. Alternatively, the system may be configured to send a CTS frame instead of the ICF Response frame exemplified in Figures 9A and 9B. In this case, the CTS frame may be returned every 20 MHz across all links and bandwidths specified in the ICF.

[0078] Next, STA102 updates its own communication parameters to match the communication parameters corresponding to NPCS. Subsequently, STA102 begins frame waiting processing in NPCS. Specifically, STA102 updates its own communication parameters with the communication parameters included in ICF. In other words, STA102 switches to the HighCapability communication condition for high-speed and high-reliability communication.

[0079] AP101, which waited during the delay period, sends a data frame to STA102 (F405). AP101 sends the data frame with transmission parameters corresponding to the HighCapability notified in F403.

[0080] Upon receiving a data frame, STA102 sends back an Ack frame as a response frame to the received data frame (F406). STA102 and AP101 can transmit downlink data by repeatedly performing the sequences indicated by F405 and F406 during the grace period indicated by the Duration field of the ICF.

[0081] When AP101 determines that it has completed a series of data transmissions to STA102, it transmits a CF-End frame or a QoS Null frame (F407). This frame functions to terminate the NPCS operating state and prompt a transition to the DPSCS state. The frame prompting the transition to DPSCS is not limited to this, and other frames may also be used. For example, it may be a control frame newly defined for the DPS function. Upon receiving the CF-End frame or QoS Null frame, STA102 changes its operating state back to DPSCS. That is, STA102 switches to the LowCapacity communication condition, which intentionally limits functionality for power saving purposes.

[0082] Figure 4 illustrates a case where downlink communication is triggered by an ICF issued by AP101. On the other hand, if STA102 decides to perform high-speed and / or high-reliability communication on its own, such as when uplink data is generated, it can determine the communication condition corresponding to NPCS and transition to NPCS. After transitioning to NPCS, STA102 performs a CCS (Clear Channel Assessment) with transmission parameters corresponding to the updated communication condition, and sends a CTS frame if it determines that it has gained channel access. The system should be configured to send a data frame when it receives an RTS frame from AP101 in response to the CTS frame. After completing a series of data transmissions, STA102 decides to switch the operating mode to DPSCS and sends a CF-End frame. Alternatively, instead of a CF-End frame, a QoS Null frame or QoS data frame may be sent with the RDG / More PPDU subfield of the CAS Control field set to 0. Upon sending such a frame, STA102 transitions its operating state to DPSCS. That is, STA102 switches to a LowCapacity communication condition with intentionally limited functionality. Furthermore, considering cases where the AP side performs power saving using DPS, STA102 may be configured to send an ICF from STA to AP before starting data transmission when uplink data is generated.

[0083] Although omitted in Figure 4 due to space limitations, STA102, when it determines that the operating mode should be changed to Awake Mode depending on the communication status, sends a request to AP101 to disable DPS. Upon receiving this request, AP101 sends a response frame indicating that it has accepted the request to disable DPS. In these DPS Disabling sequences, the request for disabling can be made using a data frame in which 0 is stored in the DPS Mode 831 of the A-Control field, as explained using Figure 8. Alternatively, the request for disabling can be made using the Dynamic Power Saving Mode Notification frame, as explained using Figure 7. When requesting disabling, STA102 stores 0 in the DPS Mode field 711 included in the frame and requests disabling.

[0084] <Communication control utilizing the DPS function> Next, the communication control utilizing the DPS function of this embodiment will be explained using the flowcharts in Figures 10 to 12.

[0085] Figures 10 and 12 are flowcharts illustrating an example of communication control in STA102, and Figure 11 is a flowchart illustrating an example of communication control in AP101.

[0086] Each process shown in the flowcharts of Figures 10 and 12 is executed by the processor of the control unit 202 of STA102 executing a computer program stored in the memory unit 201. Some processes, such as transmission and modulation, are realized through the cooperation of the processor of the control unit 202, various processors, ASICs, DSPs, FPGAs, antennas, and the ASICs, DSPs, FPGAs, etc., that constitute the communication unit 206, as well as the ASICs, DSPs, FPGAs, etc., that constitute the control unit 202. However, this is not limited to this configuration; it is also possible to configure the communication unit 206 and the antenna to cooperate in executing each process shown in the flowchart. When it is necessary to clearly indicate the subject of the process, the functional unit described in Figure 3 will be used as the subject. Controls shown by dotted lines are optional and do not necessarily need to be executed.

[0087] Furthermore, each process shown in the flowchart of Figure 11 is executed by the processor of the control unit 202 of AP101 executing a computer program stored in the memory unit 201. Note that some processes, such as transmission and modulation, are realized through the cooperation of the processor of the control unit 202, the various processors, ASICs, DSPs, and FPGAs constituting the communication unit 206, and the ASICs, DSPs, and FPGAs constituting the control unit 202. However, this is not limited to this configuration; it is also possible to configure the communication unit 206 and the antenna to cooperate in executing each process shown in the flowchart. When it is necessary to clearly indicate the subject of the process, the functional unit described in Figure 3 will be used as the subject. Note that the controls shown by the dotted lines are optional controls and do not necessarily need to be executed.

[0088] First, the control of STA102 will be explained using Figure 10. The processes shown in Figure 10 are excerpts of the series of processes from when STA102 discovers APs such as AP101 and decides whether to utilize DPS Mode. Figure 12 shows an excerpt of the specific processes when it is decided to utilize the DPS function.

[0089] In S1000, the control unit 202 of STA102 determines whether to start a connection with AP101 or the like. If it determines to start a connection, it proceeds to S1001. If it does not determine to start a connection, it waits until the conditions for determining that a connection with AP should be started are met.

[0090] In S1001, the control unit 202 performs the connection process described in Figure 4 and acquires AP Capacity information from frames received from APs such as AP101 for the connection process. STA102 also executes the connection process shown in Figure 4 and completes the connection with the destination AP such as AP101. At the time the connection is completed, the DPS function is disabled, and STA102 operates in Active Mode. That is, it starts operating with communication parameters that enable high-speed and / or high-reliability communication, corresponding to the HighCapacity negotiated with the AP during the connection process.

[0091] In S1002, the mode control unit 302 refers to the user setting stored in the memory unit 201, which determines whether to enable or disable the DPS function. The control unit 302 then determines whether the user setting is configured to disable the DPS function. If it determines that the user setting is configured to disable the DPS function, the process proceeds to S1009. On the other hand, if it determines that the user setting is not configured to disable the DPS function, the process proceeds to S1003.

[0092] In S1003, the mode control unit 302 determines whether the destination AP to which STA 102 is connected supports the DPS function. Specifically, in S1001, if the DPS Support field 504 of the Capability information obtained from the destination AP is set to 1, it is determined that the DPS function is supported. If it is determined that the DPS function is supported, the process proceeds to S1005; if it is determined that the DPS function is not supported, the process proceeds to S1009.

[0093] In S1005, the mode control unit 302 determines whether an MLO NSTR link has been established with the connected AP. If it determines that an NSTR link has been established, the process proceeds to S1009; if it determines that an NSTR link has not been established, the process proceeds to S1006. More specifically, the control unit 302 determines that an NSTR link has not been established if an MLO STR link or a single link has been established.

[0094] In S1006, the control unit 302 obtains the current battery level and the charging status (indicating whether or not it is charging) from the OS, which centrally manages the operation of the STA 102 (not shown). If the obtained battery level is below a threshold and the charging status is not charging, the control unit 302 determines that the battery is in a Low state and proceeds to S1009. On the other hand, if the obtained battery level is greater than the threshold, or below the threshold but the charging status is charging, the control unit 302 determines that the battery is not in a Low state and proceeds to S1007. The battery threshold used in this determination can be, for example, 20%.

[0095] In S1007, the control unit 302 determines whether the communication quality with AP101 is below a threshold. If it determines that the communication quality with AP101 is below a predetermined threshold, the process proceeds to S1009. If it determines that the communication quality with AP101 is higher than the predetermined threshold, the process proceeds to S1008.

[0096] In S1008, the control unit 302 determines whether the low-latency communication application is running. If it determines that the low-latency communication application is running, the process proceeds to S1009; if it determines that the low-latency communication application is not running, the process proceeds to S1010. This determination is made in cooperation with the OS that manages the running application (process). Alternatively, instead of this determination, the system may determine whether low-latency communication is required based on the QoS parameters of IP packets received from the destination AP or IP packets sent to the destination AP. In this case, the control unit 303 should proceed to S1009 if it determines that low-latency communication is required.

[0097] In S1009, the control unit 303 decides not to use the DPS function and maintains operation in Active Mode. On the other hand, in S1010, the control unit 303 decides to use the DPS function and transitions the operation mode of STA102 to DPS Enable Mode. The specific control when transitioning to DPS Enable Mode will be described later with reference to Figure 12.

[0098] Next, the control of AP101 will be explained using Figure 11. Each control shown in Figure 11 represents a process that is executed after power is supplied to AP101, the startup sequence is completed, and normal operation as an AP has begun.

[0099] In S1100, the frame processing unit 301 of AP101 determines whether it is necessary to transmit data to the STA of NPCS. If it determines that it is necessary to transmit data to the STA of NPCS, the process proceeds to S1101. If it determines that it is not necessary to transmit data to the STA of NPCS, the process proceeds to S1107.

[0100] In S1101, the frame processing unit 301 identifies the traffic type and estimates the traffic volume required for data transmission to the destination STA, which was determined to require data transmission in S1100. For example, the processing unit 301 identifies the traffic type to which the data belongs based on the QoS information of the data. Alternatively, for example, the processing unit 301 stores past communication records and estimates the traffic volume, which is a characteristic of the traffic that will be generated, by comparing these communication records with the characteristics of the data to be transmitted (e.g., source information / destination information of the data). The estimation method is not limited to this.

[0101] In S1002, the processing unit 301 determines whether the estimated traffic should be transmitted while maintaining the DPSCS of the destination STA. If it determines that the estimated traffic should be transmitted while maintaining the DPSCS of the destination STA, the process proceeds to S1103. On the other hand, if it does not determine that the estimated traffic should be transmitted while maintaining the DPSCS of the destination STA (i.e., if it determines that it should transition to NPCS), the process proceeds to S1104. For example, it determines whether the transmission time when transmitting the estimated traffic amount at the transmission rate when maintaining the DPSCS will fit within a predetermined time. If it determines that it will fit within the predetermined time, it determines that the estimated traffic should be transmitted while maintaining the DPSCS of the destination STA.

[0102] In S1103, the processing unit 301 works in cooperation with the RXTX control unit 303 to set DPSCS communication parameters corresponding to the destination STA for the communication unit 206 and the antenna 207 as transmission parameters. Subsequently, the processing unit 301 works in cooperation with the transmitting / receiving unit 304, the communication unit 206, and the antenna 207 to transmit data using the DPSCS communication parameters. Once data transmission is complete, the communication parameters are updated to normal communication parameters, and the process proceeds to S1101.

[0103] Meanwhile, in S1104, the processing unit 301, in cooperation with the other units, transmits the ICF described in Figure 8 to the destination STA. At this time, the processing unit 301, in cooperation with the mode control unit 302, determines the communication parameters to be used when the destination STA transitions to NPCS, based on the traffic characteristics (traffic type and traffic volume) identified and estimated in S1101. At this time, the mode control unit 302 manages the determined communication parameters and operating state as current state information associated with the destination STA. In other words, the control unit 302 updates the operating state included in the state information corresponding to the destination STA from DPSCS to NPCS, and stores the communication parameters to be used in NPCS as state information. Then, the processing unit 301 transmits the ICF, which includes the communication conditions corresponding to the determined communication parameters in field 805.

[0104] In S1105, the processing unit 301 works in cooperation with the control units 302 and 303, the transmitting / receiving unit 304, the communication unit 206, and the antenna 207 to wait for the transition time to NPCS, and then transmits data to the destination STA using the communication parameters notified via ICF. When the processing unit 301 determines that the transmission of a series of traffic data to the destination STA has been completed based on the data accumulation status in the transmission buffer, etc., it proceeds to S1106.

[0105] In S1106, the processing unit 301 transmits a CF-End frame or a QoS Null frame in accordance with the completion of a series of traffic transmissions. The processing unit 301 then instructs the mode control unit 302 to update the operation state of the destination STA to DPSCS. Upon receiving this instruction, the control unit 302 updates the operation state included in the state information corresponding to the destination STA from NPCS to DPSCS.

[0106] In S1107, the mode control unit 302 determines whether DPS enabling / disabling is necessary with respect to the STA. Specifically, the control unit 302, in cooperation with each unit, determines that DPS enabling / disabling is necessary when it receives a DPS Operating Mode Notification frame. Furthermore, the control unit 302, in cooperation with each unit, determines that DPS enabling / disabling is necessary when it receives a data frame in which "0" or "1" is specified in the DPS Mode field 831 of the A-Control field. In addition, the control unit 302 determines whether DPS enabling / disabling is necessary for a particular STA based on the communication status. For example, it can be determined that DPS needs to be enabled for an Active Mode STA where the data transmission frequency has decreased. Also, for example, it can be determined that DPS needs to be disabled for a DPS-Enabled Mode STA where a large amount of downlink data or low-latency data is generated. This means that, based on the communication status known to the AP, the AP decides that it should change the operating mode for specific STAs that are not suitable or are estimated to become unsuitable for the current operating mode.

[0107] If it is determined that enabling / disabling the DPS is necessary, the process proceeds to S1108. If it is determined that enabling / disabling the DPS is not necessary, the process proceeds to S1109.

[0108] In S1108, the control unit 302 works in cooperation with the other units to perform the DPS Enable / Disable procedure. Specifically, when the control unit 302 receives a data frame containing the DPS Mode field 831 in the DPS Operating Mode Notification frame or A-Control field, it transmits a response frame. The mode control unit 302 also updates the information indicating the operating mode of the destination STA of the response frame to the new operating mode.

[0109] Furthermore, if the AP determines that the operating mode of a specific STA should be changed, it sends a data frame containing a value corresponding to the determination result in the DPS Mode field 831 of the A-Control field, requesting the specific STA to change its operating mode. In some cases, a DPS Operating Mode Notification frame may also be sent to request the specific STA to change its operating mode.

[0110] Upon receiving a response frame, the mode control unit 302 updates the information indicating the operating mode of the STA that sent the response frame to the new operating mode.

[0111] Meanwhile, in S1109, the control unit 202 determines whether or not to stop the AP operation.

[0112] If it is determined that the AP operation should be stopped, the series of processes is terminated. If it is not determined that the AP operation should be stopped, the process proceeds to S1110. For example, the control unit 202 can determine that the AP operation should be stopped when it receives a user operation such as pressing a shutdown button or power button (not shown).

[0113] In S1110, the control unit 202 performs other communication controls. Specifically, it performs connection control as described in Figure 4, and communication control with Active Mode STAs and STAs whose operating state is NPCS. As mentioned above, an STA whose operating state is DPSCS may spontaneously transition to the NPCS operating state and perform data communication to the AP using communication parameters corresponding to HighCapability. When the control unit 302 receives data from an STA whose currently managed state information is DPSCS using communication parameters corresponding to HighCapability, it updates the operating state of the STA that sent the data. That is, it updates the operating state included in the state information of the currently managed source STA from DPSCS to NPCS.

[0114] Finally, using Figure 12, we will explain the communication control in STAs such as STA102 that have transitioned to DPS Enable Mode.

[0115] In S1200, the mode control unit 302 of STA102, in cooperation with the processing unit 301 and the frame transmission / reception unit 304, executes the DPS enabling procedure. Specifically, it transmits a data frame in which "1" is stored in the DPS Mode field 831 of the A-Control field as described in Figure 8. This data frame may be a QoS Null type data frame. Upon receiving a response signal such as Ack or BlockAck for this frame, the mode control unit 302, in cooperation with the RXTX control unit 303, the communication unit 206, and the antenna 207, changes the transmission and reception parameters for DPSCS. Specifically, it changes them to transmission and reception parameters corresponding to the parameters stored in the A-Control fields 832 to 834. Alternatively, the enabling procedure may be started using a different frame. Specifically, a DPS Operating Mode Notification frame containing "1" in the DPS Mode field is transmitted. Upon receiving a normal response to the frame, the mode control unit 302, in cooperation with the RXTX control unit 303, the communication unit 206, and the antenna 207, changes the transmission and reception parameters for DPSCS. If the DPS Operating Mode Notification frame includes field 705, the transmission and reception parameters are changed to those corresponding to the parameters indicated in field 705. If the DPS Operating Mode Notification frame does not include field 705, the transmission and reception parameters are changed to those previously shared from the connected AP, such as AP 101, using the UHR Operation Element.

[0116] In S1201, the processing unit 301 works in cooperation with the other units to determine whether it has received a frame addressed to itself. If it determines that it has received a frame addressed to itself, it proceeds to S1202; otherwise, it proceeds to S1203.

[0117] In S1202, the processing unit 301 determines whether the received frame is a DPS ICF. If it determines that the received frame is a DPS ICF, the process proceeds to S1207; otherwise, the process proceeds to S1206. A DPS ICF is, for example, the frame described in Figure 8.

[0118] In S1203, the processing unit 301 determines whether it is necessary to send data to the AP. If it determines that it is necessary to send data to the AP, the process proceeds to S1204. If it determines that it is necessary to send data to the AP, the process proceeds to S1210.

[0119] In S1204, the processing unit 301 identifies and estimates the traffic characteristics. The specific processing details are the same as those described in S1101 for AP control, so the explanation is omitted.

[0120] In S1205, the mode control unit 302 determines whether to communicate the traffic identified and estimated in S1204 while maintaining DPSCS. If it determines that communication should be conducted while maintaining DPSCS for the traffic, the process proceeds to S1206. If it does not determine that communication should be conducted while maintaining DPSCS for the traffic, the process proceeds to S1207. For example, it determines whether the transmission time for transmitting the estimated traffic volume at the communication rate while maintaining DPSCS will fit within a predetermined time. If it determines that it will fit within the predetermined time, it determines that the estimated traffic should be transmitted while maintaining the DPSCS of the destination STA.

[0121] In S1206, the control unit 202, in cooperation with each unit, performs data communication using communication parameters for DPSCS. In the case of data reception processing, the control unit 202 receives a frame using the configured DPSCS reception parameters, analyzes the payload of the received frame as appropriate, and processes it. In the case of data transmission processing, the control unit 202 generates a frame containing the data to be transmitted using the configured DPSCS reception parameters and transmits it. Once data communication via DPSCS is complete, the control unit 202 proceeds to S1210.

[0122] In S1207, the mode control unit 302 works in cooperation with each unit to change the communication parameters to the HighCapability for NPCS. If an ICF has not been received, it sets the communication parameters to the HighCapability used in the Active Mode agreed upon during the connection process. If an ICF has been received, it changes the communication parameters to those stored in the ICF.

[0123] In S1208, the control unit 202 performs data communication using the modified communication parameters. In the case of data transmission, the control unit 202 performs data transmission using the modified transmission parameters for NPCS, and in the case of data reception, it performs data reception using the modified reception parameters. Once the series of data communications is complete, the control unit 202 proceeds to S1209.

[0124] In S1209, the mode control unit 302, in cooperation with the other units, communicates a CF-End / QoS Null frame. After communicating the frame, the mode control unit 302, in cooperation with the other units, changes the communication parameters to the communication parameters corresponding to LowCapacity for DPSCS.

[0125] In S1210, the mode control unit 302 determines whether it is necessary to disable the DPS function. Specifically, it determines whether it is necessary to disable the DPS function based on a determination similar to the determination described in S1005 to S1008 above. That is, if any of the following conditions are met, such as the battery level falling below a threshold, the communication link being reconfigured to an NSTR link pair, or the communication quality being below a predetermined threshold, it is determined that it is necessary to disable the DPS function. It is also determined that it is necessary to disable the DPS function if the condition that a low-latency communication application is running is met. Furthermore, it is determined that it is necessary to disable the DPS function if a user setting is changed while operating in DPS Enable Mode, based on a determination similar to the determination described in S1002, namely, if the setting is changed to disable the DPS function while operating in DPS Enable Mode. If it is determined that the DPS function needs to be disabled, the process proceeds to S1211. If it is determined that the DPS function does not need to be disabled, the process proceeds to S1201.

[0126] In S1211, the mode control unit 302, in cooperation with the other units, executes the DPS Disabling procedure. Specifically, it transmits a data frame in which "0" is stored in the DPS Mode of the A-Control field. This data frame may be a QoS Data type data frame containing actual data, or a QoS Null type data frame. Upon receiving a response signal such as Ack or BlockAck for this frame, the mode control unit 302, in cooperation with the other units, changes the transmission and reception communication parameters to communication parameters corresponding to HighCapability for Active Mode. These parameters to be changed are the Active Mode communication parameters that were negotiated in advance during the connection process. Alternatively, the Enabling procedure may be started using a different frame. Specifically, a DPS Operating Mode Notification frame containing "0" in DPS Mode is transmitted. Upon receiving a normal response to this frame, the mode control unit 302, in cooperation with the other units, changes the transmission and reception communication parameters to communication parameters corresponding to High Capability for Active Mode.

[0127] The control described above allows the activation or deactivation of the DPS function to be communicated using the A-Control field of the data frame. By adopting this procedure, it becomes possible to send a request to change the operating mode of the DPS function when transmitting the data frame. This process has the effect of reducing communication overhead compared to simply exchanging a request to change the operating mode of the DPS function.

[0128] <Modification 1> In the above embodiment, examples were given of notifying the MCS, link, etc. used in the operating state of the DPSCS using frames including a UHR Operation element or a DPS Operating Mode Notification frame. However, it is not limited to this. It is also possible to configure it to notify only the information that identifies the link corresponding to 607, and to use predefined communication parameters for other communication parameters. Predefined communication parameters may include, for example, communication parameters that use one spatial stream, the minimum MCS to receive control frames such as ICF, and use only the primary 20 MHz bandwidth.

[0129] <Modification 2> In the above embodiment, an example was given in which the ICF frame includes communication parameters to be used after transitioning to NPCS, but it is not limited to this. For example, the transmission of such communication parameters can be omitted. In this case, it is sufficient to configure the system to use the default communication parameters when returning to NPCS. The default communication parameters can be, for example, the communication parameters used when operating in Active Mode negotiated during connection processing.

[0130] <Modification 3> The information regarding whether or not the DPS function is supported, which is included in the UHR Capabilities element as exemplified in Figure 5, can also be configured to be included in the Multi-Link Element. For example, a new field such as Extended MLD Capabilities can be added to the Common Info field in the Basic Multi-Link Element of the Multi-Link Element. This field can then be configured to include information equivalent to 504. This element can be included in ML Probe Request, ML Probe Response, Beacon, etc.

[0131] <Modification 4> STA 102 may be configured to send a management frame including a UHR MAC Capabilities Element with "1" set in DPS Support and "0" set in DPS Assisting Support, as illustrated in Figure 5. In this case, the TXS Mode 2 Support field of the EHT MAC Capabilities Element is configured to be set to "0". The primary case in which an STA would like to assist with DPS is assumed to be when it communicates directly with a peer STA in DPS state using High Capability. STAs that do not intend to use the function to communicate directly with a peer STA can be configured to set DPS Assisting Support to "0". In that case, you should configure the TXS Mode 2 Support function, which is also closely related to direct communication with peer STA in conjunction with the aforementioned setting, to be set to "0" to indicate that it is not supported.

[0132] <Other Embodiments> The present invention can also be realized by supplying a program that implements one or more of the functions of the above embodiments to a system or device via a network or storage medium, and by having one or more processors in the computer of that system or device read and execute the program. It can also be realized by a circuit (for example, an ASIC) that implements one or more functions.

[0133] The invention is not limited to the embodiments described above, and various modifications and variations are possible without departing from the spirit and scope of the invention. Accordingly, claims are attached to disclose the scope of the invention.

[0134] This application claims priority based on Japanese Patent Application No. 2025-026425, filed on 21 February 2025, and all of its contents are incorporated herein by reference.

[0135] 101 AP MLD 102 non-AP MLD 206 Communication Department

Claims

1. A communication device that performs wireless communication in accordance with the IEEE 802.11 standard series, comprising a transmission control means that controls the transmission of a frame to another communication device, which includes an information element that stores information indicating whether it supports a second mode in which the device waits for communication with at least two or more conditions among the number of communication links, bandwidth, and spatial streams changed to conditions that are estimated to consume less power than the first mode, in order to suppress the amount of power consumed when waiting for communication compared to the power consumption when waiting for communication in a first mode, and further controls the transmission control means to transmit to the other communication device whether the second mode is enabled or disabled using the A-Control field of the MAC header of a data frame different from the frame.

2. The communication device according to claim 1, characterized in that the transmission control means transmits the information to another communication device by including the information element in a Beacon frame or Association Response frame and transmitting it.

3. The communication device according to claim 1 or 2, characterized in that the transmission control means transmits the information to another communication device by including the information element in at least an Association Request frame.

4. The communication device according to any one of claims 1 to 3, wherein the transmission control means transmits the frame in which the information element stores information indicating that the second mode is supported, establishes a link for communication with another communication device, and, if the other communication device is operating in the first mode, transmits the data frame to the other communication device using the A-Control field to indicate the activation of the second mode, and then changes two or more conditions to conditions that are estimated to consume less power than the first mode, and transitions the operating mode of the communication device to the second mode.

5. The communication device according to claim 4, wherein the communication device is a Non-AP (Access Point) MLD (Multi-Link Device), and when operating in the first mode, it can establish multiple links with the other communication device and perform STR communication, and the transition means transitions the operating mode to the second mode by changing the condition to one condition in which communication is possible with the other communication device over one link with a bandwidth of 20 MHz and communication is performed with one spatial stream.

6. The communication device according to any one of claims 1 to 5, characterized in that the information element is an information element included in UHR MAC Capabilities Element.

7. The communication device according to any one of claims 1 to 6, wherein the information element can store 1 or 0, where 1 indicates that the second mode is supported, and 0 indicates that the second mode is not supported or that the second mode is disabled.

8. The communication device according to any one of claims 1 to 7, characterized in that the frame in which the information elements are stored is at least one of the following: Beacon frame, Probe Request frame, Probe Response frame, Association Request frame, Association Response frame, Reassociation Request frame, Reassociation Response frame, and Action frame.

9. A method for controlling a communication device that performs wireless communication in accordance with the IEEE 802.11 standard series, comprising: a first transmission control step of controlling the device to transmit to another communication device a frame containing an information element that stores information indicating whether it supports a second mode in which the device waits for communication with at least two or more conditions among the number of communication links, bandwidth, and spatial streams changed to conditions that are estimated to consume less power than the first mode, in order to suppress the amount of power consumed when waiting for communication compared to the power consumption when waiting for communication in a first mode; and a second transmission control step of controlling the device to transmit to another communication device whether it enables or disables the second mode using the A-Control field of the MAC header of a data frame different from the frame.

10. A program for causing a computer to execute the control method of the communication device described in claim 9.

11. A communication device that performs wireless communication in accordance with the IEEE 802.11 standard series, characterized by having a transmission control means that controls the transmission of a frame to another communication device in which 0 is stored in the TXS Mode 2 Support field of the EHT MAC Capabilities Element, 1 is stored in the DPS Support field of the UHR MAC Capabilities Element, and 0 is stored in the DPS Assisting Support field.

12. The communication device according to claim 11, characterized in that the communication device is Non-AP STA.

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