Communication device, communication method, and program

Abstract

To provide a communication device capable of enabling a Sharing AP to appropriately determine the transmit power of an OBSS AP on Coordinated Spatial Reuse.SOLUTION: In a wireless communication network, when executing Coordinated Spatial Reuse as specified in the IEEE802.11 standard, an access point AP acquires information on other access points and notifies a connected station of the information and an instruction to set the power management mode to an active mode.SELECTED DRAWING: Figure 7

Description

Technical Field

[0001] The present invention relates to wireless communication technology.

Background Art

[0002] In recent years, with the development of information and communication technology, the amount of Internet usage has been increasing year by year, and various communication technologies have been developed to meet the increasing demand. Among them, wireless local area network (WLAN) technology has realized an improvement in throughput in Internet communications such as packet data, voice, and video by WLAN terminals, and various technology developments are still being actively carried out.

[0003] In the development of WLAN technology, a number of standardization efforts by IEEE, which is a standardization organization for WLAN technology, have played an important role. As one of the WLAN communication standards, the IEEE 802.11 series is known. Here, IEEE is an abbreviation for Institute of Electrical and Electronics Engineers. Note that WLAN is an abbreviation for Wireless Local Area Network. The IEEE 802.11 series standards include standards such as IEEE 802.11a / b / g / n / ac / ax standards.

[0004] Patent Document 1 discloses that in the IEEE 802.11ax standard, wireless communication by OFDMA (Orthogonal Frequency Division Multiple Access) is performed. In the IEEE 802.11ax standard, high peak throughput is realized by performing wireless communication by OFDMA.

[0005] In recent years, the development of the IEEE 802.11be standard has been considered as a new standard in the IEEE 802.11 series. In addition to adopting OFDMA similar to IEEE 802.11ax, IEEE 802.11be is undergoing technical studies to improve frequency utilization efficiency by using Spatial Reuse. Here, among Spatial Reuse, Spatial Reuse in which one AP determines the transmit power of other APs is called CSR (Coordinated Spatial Reuse).

[0006] Typically, wireless LAN systems employ CSMA / CA (Carrier Sense Multiple Access with Collision Avoidance) to prevent collisions between two or more communications. CSR (Shared Service Set) enables simultaneous communication by adjusting the transmit power of wireless LAN devices to prevent interference between communications, thereby improving frequency utilization efficiency. In CSR, a method is being considered for how a Sharing AP determines the transmit power of an OBSS AP. Specifically, the Sharing AP determines the transmit power of the OBSS AP based on the downlink reception sensitivity to the STA connected to its device and the path loss between the STA and the OBSS AP. Here, OBSS stands for Overlapping Basic Service Set. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Japanese Patent Publication No. 2018-50133 [Overview of the project] [Problems that the invention aims to solve]

[0008] In a CSR (Cross-Linked Service Area), for a Sharing AP to determine the transmit power of an OBSS AP, the STA (Stand-Aid) connected to the Sharing AP must receive packets containing transmit power information from the OBSS AP to calculate the path loss between the STA and the OBSS AP. However, if the STA's power management mode is Power Save mode (PSmode), downlink communication only occurs at specific times, preventing the STA from receiving packets from the OBSS AP and thus making it impossible to calculate the path loss. [Means for solving the problem]

[0009] To solve the above problems, the communication device of the present invention is A communication device operating as a station as defined by the IEEE 802.11 standard, comprising: receiving means for receiving a predetermined frame for performing Coordinated Spatial Reuse as defined by the IEEE 802.11 standard from an access point included in the same Basic Service Set (BSS) as the communication device; and setting means for setting the power management mode to a second power mode with higher power consumption than a first power mode based on the reception of the predetermined frame by the receiving means. It is characterized by having the following features.

[0010] Furthermore, the communication method of the present invention is a communication method for stations as defined in the IEEE 802.11 standard, and the above station The system is characterized by having a receiving step of receiving a predetermined frame for performing Coordinated Spatial Reuse as defined in the IEEE 802.11 standard from an access point included in the same Basic Service Set (BSS), and a setting step of setting the power management mode to a second power mode with higher power consumption than the first power mode based on the receipt of the predetermined frame. [Effects of the Invention]

[0011] In a CSR (Corporate Social Responsibility) scenario, the Sharing AP can appropriately determine the transmission power of the OBSS AP. [Brief explanation of the drawing]

[0012] [Figure 1] A diagram showing the network configuration. [Figure 2] A diagram showing an example of the hardware configuration for AP and STA. [Figure 3] A diagram showing an example of AP's functional configuration. [Figure 4]Figure showing a configuration example of a Measurement announcement frame. [Figure 5] Figure showing the configuration of a Neighbor Report element. [Figure 6] Figure showing a configuration example of a Measurement Request element. [Figure 7] Flowchart showing the processing performed by an AP. [Figure 8] Figure showing a functional configuration example of a STA. [Figure 9] Figure showing a configuration example of a Measurement Report element. [Figure 10] Flowchart showing the processing performed by a STA. [Figure 11] Flowchart showing the processing performed by an AP. [Figure 12] Figure showing a functional configuration example of a STA. [Figure 13] Flowchart showing the processing performed by a STA.

Embodiments for Carrying Out the Invention

[0013] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the invention according to the claims. Although a plurality of features are described in the embodiments, not all of these plurality of features are essential for the invention, and the plurality of features may be arbitrarily combined. Further, in the accompanying drawings, the same or similar configurations are denoted by the same reference numerals, and redundant descriptions are omitted.

Examples

[0014] (Example 1) (Network Configuration) FIG. 1 shows a configuration example of a wireless communication network in this embodiment.

[0015] Wireless communication network 101 consists of one access point (AP102) and one or more stations (STA103), which are communication devices compliant with the IEEE 802.11be standard. Similarly, wireless communication network 104 consists of one access point (AP105) and one or more stations (STA106), which are communication devices compliant with the IEEE 802.11be standard. Each communication device can communicate in the 2.4GHz band, 5GHz band, and / or 6GHz band. However, the frequency band used by each communication device is not limited to these, and different frequency bands, such as the 60GHz band, may be used. In addition, each communication device can communicate using a bandwidth of 20MHz, 40MHz, 80MHz, 160MHz, and 320MHz. AP102, AP105 and STA103, STA106 can perform OFDMA communication to multiplex signals from multiple users and realize multi-user (MU) communication. OFDMA stands for Orthogonal Frequency Division Multiple Access. Furthermore, AP102, AP105 and STA103, STA106 may also perform MIMO (Multiple-Input And Multiple-Output) communication. In this case, AP102, AP105 and STA103, STA106 have multiple antennas, with each transmitting different signals from its antennas using the same frequency channel. The receiving side simultaneously receives all signals arriving from multiple streams using its multiple antennas, separates the signals from each stream, and decodes them. By performing MIMO communication in this way, AP102, AP105 and STA103, STA106 can communicate more data in the same amount of time compared to not performing MIMO communication. Additionally, AP102 and AP105 can establish wireless links with STA103 and STA106, respectively, through connection processes such as the association process defined in the IEEE 802.11 series standards.The wireless communication network configuration shown in Figure 1 is merely an example for illustrative purposes. For example, a network including numerous be devices, ax devices, and legacy devices (devices conforming to IEEE 802.11a / b / g / n / ac standards) may be configured over a wider area. Furthermore, AP102 and STA103 may support legacy standards (IEEE 802.11a / b / g / n / ac standards) that predate IEEE 802.11ax. They may also support other communication standards such as Bluetooth®, NFC, UWB, Zigbee, and MBOA. UWB stands for Ultra Wide Band, MBOA for Multi Band OFDM Alliance, OFDM for Orthogonal Frequency Division Multiplexing, and NFC for Near Field Communication. UWB includes wireless USB, wireless 1394, and Winet. Wired communication standards such as wired LAN may also be supported.

[0016] Specific examples of AP102 and AP105 include, but are not limited to, wireless LAN routers, PCs, and smartphones. AP102 and AP105 can be any communication device capable of performing OFDMA communication with other communication devices. AP102 and AP105 may also be information processing devices such as wireless chips capable of performing wireless communication compliant with the IEEE 802.11be standard. Similarly, specific examples of STA103 and STA106 include, but are not limited to, cameras, tablets, smartphones, PCs, mobile phones, and video cameras. STA103 and STA106 can be any communication device capable of performing OFDMA communication with other communication devices. STA103 and STA106 may also be information processing devices such as wireless chips capable of performing wireless communication compliant with the IEEE 802.11be standard. Furthermore, while Figure 1 shows multiple networks consisting of one AP and one STA, the number of networks and the number of APs and STAs are not limited to this. Wireless communication networks 101 and 104 are located adjacent to each other, with the AP performing CSR being the Sharing AP, and the OBSS AP as seen from the Sharing AP being the Shared AP. In this embodiment, AP102 is the Sharing AP, and the functional configuration and processing of AP102 and STA103 in the procedure for measuring path loss between STA103, which is connected to AP102, and OBSS AP105 will be described. AP105 and STA106 have similar functional configurations and processing functions, and the same effect can be obtained even if AP105 becomes the Sharing AP. Furthermore, the same applies when there are multiple other networks. Information processing devices such as wireless chips are connected to antennas for transmitting the generated signals.

[0017] (AP and STA hardware configuration) Figure 2 shows an example of the hardware configuration for AP102 and AP105.

[0018] The memory unit 201 is composed of one or more memories such as ROM and RAM, and stores various information such as computer programs for performing various operations described later, and communication parameters for wireless communication. ROM stands for Read Only Memory, and RAM stands for Random Access Memory. In addition to memories such as ROM and RAM, the memory unit 201 may also use storage media such as flexible disks, hard disks, optical disks, magneto-optical disks, CD-ROMs, CD-Rs, magnetic tapes, non-volatile memory cards, and DVDs. Furthermore, the memory unit 201 may have multiple memories.

[0019] The communication unit 206 controls wireless communication compliant with the IEEE 802.11be standard. In addition to the IEEE 802.11be standard, the communication unit 206 may also control wireless communication compliant with other IEEE 802.11 standard series, or wired communication such as wired LAN. The communication unit 206 controls the antenna 207 to transmit and receive signals for wireless communication generated by the control unit 202. AP102 and AP105 may have multiple communication units 206. AP102 and AP105 with multiple communication units 206 establish at least one link per communication unit 206 when establishing multiple links in multilink communication. Alternatively, AP102 and AP105 may establish multiple links using a single communication unit 206. In this case, the communication unit 206 performs communication over multiple links by switching frequency channels that operate in time division. Furthermore, if AP102 and AP105 support NFC, Bluetooth, or other standards in addition to the IEEE 802.11be standard, they may control wireless communication compliant with these communication standards. Also, if AP102 and AP105 can perform wireless communication compliant with multiple communication standards, they may be configured to have separate communication units and antennas corresponding to each communication standard. AP102 and AP105 communicate data such as image data, document data, and video data, respectively, with STA103 and STA106 via the communication unit 206. The antenna 207 may be configured separately from the communication unit 206, or it may be configured as a single module together with the communication unit 206.

[0020] Antenna 207 is an antenna capable of communication in the 2.4GHz, 5GHz, and 6GHz bands. In this embodiment, AP102 is assumed to have one antenna, but it may have different antennas for each frequency band. Also, if AP102 and AP105 have multiple antennas, they may have a communication unit 206 corresponding to each antenna.

[0021] Note that STA103 and STA106 have the same hardware configuration as AP102.

[0022] (AP102 Functional Configuration) Figure 3 shows an example of the functional configuration of AP102. AP102 includes an OBSS AP information acquisition unit 301, a frame generation unit 302, and a frame transmission / reception unit 303. These may be configured by software, or some or all of them may be configured by hardware. The OBSS AP information acquisition unit 301 acquires the capability of the OBSS AP105 that is the target of CSR by receiving beacons and management frames from OBSS AP105. The frame generation unit 302 generates a Measurement announcement frame. The Measurement announcement frame is a frame that includes information about OBSS AP105, the content of the Measurement request, and a notification of change to Non-PS mode (Active mode). An example of the frame format of the Measurement announcement frame is shown in Figure 4. In this embodiment, the Measurement announcement frame uses the Control Frame that is Reserved in the Frame Control field to create a new Type and Subtype. Furthermore, by setting the bit of Power management field 415 to 1, it notifies the STA not to enter Power Save mode. In addition, the frame body includes a Neighbor Report element as defined in IEEE802.11, as shown in Figure 5. This transmits the information of OBSS APs participating in the CSR, acquired by the OBSS AP information acquisition unit 301, to the STA. Furthermore, the frame body uses a Measurement Request element with a new Measurement Type 605 that requests a path loss measurement, as shown in Figure 6. This element is used to transmit the content of the path loss measurement request to the STA. 610 is a list of Measurement Type 605s. The Measurement announcement frame may also be created using a Management Frame or a Data Frame.Furthermore, the information and measurement requirements of OBSS AP may be modified to create new Elements, but the present invention is not limited thereto.

[0023] The frame transmission / reception unit 303 controls the transmission and reception of management frames, control frames, and data frames.

[0024] (Processing of AP102) Next, we will explain the processing in CSR that is executed by AP102 configured as described above.

[0025] Figure 7 is a flowchart showing the processing of AP102. This operation flow is performed when AP102 executes a CSR, by having the control unit 202 read and execute the computer program stored in the memory unit 201.

[0026] First, AP102 acquires the capability of OBSS APs participating in CSR by receiving beacons and management frames from APs forming OBSS (S701). Next, AP102 sends a Measurement announcement frame to its BSS STA (S702). This frame contains information about the OBSS APs to be measured for path loss, an instruction to set the STA's power management mode to Non-Power Save mode, and an instruction to the STA to start measuring path loss. Here, Non-Power Save mode refers to the active mode. After sending the Measurement announcement frame, AP102 receives a Measurement Report from the STA showing the path loss measurement results. In S703, it determines whether the Measurement Report was received. If a Measurement Report is not received and path loss information cannot be obtained after a certain period of time has elapsed since sending the Measurement announcement frame in S703, it returns to S702. In S703, if the Measurement Report is received and path loss information can be obtained, AP102 determines Yes and terminates its operation.

[0027] (STA103 Functional Configuration) Figure 8 shows an example of the functional configuration of STA103. STA103 includes a frame transmission / reception unit 801, an operating mode management unit 802, a path loss calculation unit 803, and a frame generation unit 804. These may be configured by software, or some or all of them may be configured by hardware.

[0028] The frame transmission / reception unit 801 controls the transmission and reception of management frames, control frames, and data frames.

[0029] The operating mode management unit 802 refers to the bit in the Power management field 415 of the received frame shown in Figure 4, and sets the power management mode to Non-Power Save mode when the bit is 1, and to Power Save mode when the bit is 0. Here, Non-Power Save mode indicates the active mode.

[0030] The path loss calculation unit 803 receives packets from the OBSS AP and calculates the path loss between itself and the OBSS AP from the transmitted power information and received sensitivity obtained from the received packets. The path loss can be determined by taking the difference between the transmitted power and the received sensitivity.

[0031] The frame generation unit 804 generates a Measurement Report to transmit the path loss calculation results to the AP. The Measurement Report includes at least the BSSID of the OBSS AP whose path loss was measured and information indicating the measured path loss value. To transmit this information, a new Measurement Type for measuring path loss is created in the Reserved Measurement Type of the Measurement Report element shown in Figure 9. The BSSID of the OBSS AP to be measured and the path loss value obtained by the path loss calculation unit are stored in the BSSID field 907 and the Pathloss field 908, respectively. 909 is a list of Measurement Type 905. However, the frame for transmitting the path loss measurement results may be an element other than the Measurement Report element, and the present invention is not limited thereto.

[0032] (Processing of STA103) Next, we will explain the processes performed by STA103 configured as described above. Figure 10 is a flowchart of the processes performed by STA103. Note that when STA103 performs CSR, the control unit 202 reads and executes the computer program stored in the memory unit 201. First, STA103 receives a Measurement announcement sent from the connected AP (S1001). STA103 sets the power management mode to Non-Power Save mode according to the information notified in the received Measurement announcement and starts path loss measurement (S1002). STA103 starts receiving packets from the AP to be measured, as indicated in the OBSS AP information included in the Measurement announcement received in S1002, and determines in S1003 whether or not the OBSS AP packet containing the transmitted power information can be received. If STA103 fails to receive the OBSS AP packet within a predetermined time and determines No in S1003, it attempts to receive the OBSS AP packet again. If STA103 receives a packet from the OBSS AP and determines "Yes" in S1003, it proceeds to process S1004. In S1004, it calculates the path loss between itself and the target AP and sends the calculated value as a Measurement Report to the connected AP. After sending the Measurement Report in S1004, STA103 terminates its operation.

[0033] According to this embodiment, as described above, AP102 notifies STA103 to enter Non-Power Save mode, enabling STA103 to receive packets from OBSS AP. As a result, CSR can obtain the path loss information necessary for determining the transmission power of OBSS AP.

[0034] (Example 2) In Example 1, AP102 explicitly notified STA103 of the change to Non-Power Save mode by setting a bit in the Power management field within the Measurement announcement frame. In this embodiment, the implementation on the AP side can be simplified because STA103 enters Non-Power Save mode without AP102 having to notify using the Power management field. Furthermore, because the Power management field is not used, it becomes possible to implement the notification to STA by including the Measurement announcement in the management frame, control frame, data frame, etc. In addition, by treating the path loss as a predetermined value when packets from the OBSS AP cannot be received and the path loss cannot be calculated, it is possible to handle environments where packets from the OBSS AP cannot be received by STA103. Moreover, by adding a process to return the power management mode to the state before the change after STA has completed measuring the path loss, power consumption can be minimized. In this embodiment, an embodiment is described in which the above effects can be obtained in addition to the same effects as in Example 1.

[0035] (AP functional configuration) In the functional configuration of AP102 shown in Figure 3, the functional parts that have different functions from those in Example 1 will be described, while the functional parts that have similar functions will not be described.

[0036] The frame generation unit 302 generates the Measurement announcement frame shown in Figure 4, similar to Example 1. However, in this example, the Power management field of the Measurement announcement frame is not used, and the STA is not explicitly notified of the change in power management mode. Therefore, the Measurement announcement frame in this example is a frame that includes the same Neighbor Report element and Measurement Request element as in Example 1. Alternatively, a new element containing the same information as the Neighbor Report element and Measurement Request element may be created without using the Measurement announcement frame shown in Figure 4. The created element may be included in other management frames, control frames, data frames, etc., but the present invention is not limited thereto.

[0037] (Processing of AP102) Figure 11 is a flowchart showing the operation of AP102 in this embodiment. The basic processing is the same as in Embodiment 1, and the only difference is the content of the Measurement announcement transmitted by S1101, as explained in the functional configuration of the AP in this embodiment.

[0038] (STA Functional Configuration) Figure 12 shows the functional configuration of STA in this embodiment. In the functional configuration of STA103, the same reference numbers are used for functional parts that perform the same or similar operations as in the functional configuration of Embodiment 1 (Figure 8), and redundant explanations are omitted.

[0039] In Example 1, the operation mode management unit 802 shown in Figure 8 monitored the bits in the Power management field 415 of the received frame shown in Figure 4 and changed the power management mode based on those bits. In this example, when it is determined from fields 413 and 414 of the received frame that a Measurement announcement has been received, it sets its own power management mode to Non-Power Save mode. This operation mode is managed by the operation mode management unit 1201. Therefore, the STA changes its power management mode on its own without receiving explicit notification of a power management mode change from the AP. Alternatively, the operation mode may be changed when it is determined from the ElementID of the Measurement Request element and Neighbor Report element of the received frame that a Measurement announcement has been received.

[0040] (Processing of STA103) Figure 13 is a flowchart showing the operation of STA103 in this embodiment. In the flowchart of Figure 13, processes that perform the same or similar operations as those in Embodiment 1 and the flowchart (Figure 10) are given the same reference number, and redundant explanations are omitted.

[0041] In this embodiment, STA103 receives a Measurement announcement in S1001. Upon receiving the Measurement announcement in S1001, STA103 sets the power management mode to Non-Power Save mode and starts measuring path loss (S1301). In S1003, it determines whether or not it can receive the OBSS AP packet containing the transmitted power information. If STA103 can receive the OBSS AP packet within a predetermined time, STA103 determines Yes in S1003 and proceeds to process S1004. In S1004, STA103 calculates the path loss and sends a Measurement Report to AP102. If STA103 cannot receive the OBSS AP packet within a predetermined time, STA103 determines No in S1003 and proceeds to process S1302. In S1302, STA103 counts the number of times it has attempted to receive the OBSS AP packet. If the number of attempts is less than a predetermined number, it attempts to receive the OBSS AP packet again. If the number of trials exceeds a predetermined number, STA103 determines "Yes" and proceeds to process S1303. In S1303, the path loss is not calculated but sent to AP102 as a predetermined value in the Measurement Report. Here, the predetermined path loss value is the largest value that can be represented in the Pathloss field 908, which stores the path loss value in the Measurement Report shown in Figure 9. After processing S1004 or S1303, STA103 returns the power management mode changed in S1301 to its original state and terminates processing.

[0042] According to this embodiment, the operation of AP102 and STA103 described above allows STA103 to change its power management mode on its own without receiving an explicit power management change notification from AP102, thus achieving the same effect as in Embodiment 1. In addition, it can handle environments where packets from OBSS APs cannot be received, minimizing power consumption.

[0043] (Other examples) The embodiments described above are examples, and the technical scope of the present invention is not limited thereto. The present invention includes various modifications other than those described above. CSR (Coordinated Spatial Reuse) is a method of Spatial Reuse and is a concept that includes a method by which one AP determines the transmission power of other APs. Furthermore, although the above embodiments used the IEEE 802.11be standard as an example of a wireless LAN standard, the invention is applicable to various standards (IEEE 802.11x), including legacy and successor standards of the IEEE 802.11 series, as well as other similar wireless standards.

[0044] Furthermore, the present invention can also be realized by supplying a program that implements one or more of the functions of the above-described 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 (e.g., an ASIC) that implements one or more functions. [Explanation of Symbols]

[0045] Networks 101 and 104 102, 105 AP 103, 106 STA

Claims

1. A communication device that operates as a station as defined in the IEEE 802.11 standard, Receiving means for receiving a predetermined frame for executing Coordinated Spatial Reuse as defined in the IEEE 802.11 standard from an access point included in the same Basic Service Set (BSS) as the aforementioned communication device, A communication device characterized by having setting means that sets the power management mode to a second power mode having higher power consumption than a first power mode, based on the reception means receiving a predetermined frame.

2. The communication device according to claim 1, characterized in that the predetermined frame is a frame for instructing the communication device to send a report based on the reception status of data transmitted from another access point included in another BSS different from the BSS.

3. The receiving means receives a Measurement Announcement frame as defined in the IEEE 802.11 standard as the predetermined frame, The communication device according to claim 1, characterized in that the setting means sets the power management mode of the communication device to the second power mode based on the power management mode information included in the Measurement announcement frame.

4. The device further includes a transmission means for transmitting a report to the access point included in the BSS, based on the reception status of data transmitted by the communication device from other access points included in other BSSs different from the aforementioned BSS, Based on the aforementioned report, the Coordinated Spatial Reuse is executed. The communication device according to feature 1.

5. The communication device according to claim 1, further comprising a transmission means for receiving packets transmitted from other access points and transmitting a Measurement Report based on such reception to the access point connected to the communication device, after setting the power management mode of the communication device to the second power mode using the setting means.

6. A station communication method as defined in the IEEE 802.11 standard, A receiving step of receiving a predetermined frame for executing Coordinated Spatial Reuse as defined in the IEEE 802.11 standard from an access point included in the same Basic Service Set (BSS) as the aforementioned station, A setting step of setting the power management mode to a second power mode with higher power consumption than the first power mode based on the receipt of the predetermined frame, A communication method characterized by having the following features.

7. A program for causing a computer to function as one of the means of a communication device described in any one of claims 1 to 5.

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