Base station and terminal

Abstract

To provide a base station that allows the power consumption of a wireless terminal to be reduced.SOLUTION: In a wireless communication system, a base station (10) includes first and second wireless signal processing units (130 and 140) and a link management unit (120). The link management unit sets a multi-link to a first state or a second state. In the first state, a first link using the first wireless signal processing unit and a second link using the second wireless signal processing unit are each in an active mode in which communication is possible. In the second state, the first link is in the active mode or an intermittent operation mode in which it operates intermittently, and the second link is in a dormant operation mode in which power consumption is lower than in the intermittent operation mode.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] Embodiments relate to a base station and a terminal.

Background Art

[0002] As a wireless system for wirelessly connecting a base station and a terminal, a wireless LAN (Local Area Network) is known.

Prior Art Documents

Non-Patent Documents

[0003]

Non-Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The problem is to suppress the power consumption of a wireless terminal.

Means for Solving the Problems

[0005] The base station according to the embodiment includes a first radio signal processing unit, a second radio signal processing unit, and a link management unit. The first radio signal processing unit is configured to transmit and receive radio signals using a first channel. The second radio signal processing unit is configured to transmit and receive radio signals using a second channel different from the first channel. The link management unit establishes a multi-link with a terminal using the first radio signal processing unit and the second radio signal processing unit. The link management unit sets the multi-link to a first state or a second state. In the first state, each of a first link using the first radio signal processing unit and a second link using the second radio signal processing unit is in an active mode in which communication is possible. In the second state, the first link is in an active mode or an intermittent operation mode in which it operates intermittently, and the second link is in an operation stop mode in which power consumption is lower than that in the intermittent operation mode.

Advantages of the Invention

[0006] The base station according to the embodiment can suppress the power consumption of the wireless terminal.

Brief Description of the Drawings

[0007]

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DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, the wireless system 1 according to the embodiment will be described with reference to the drawings. The embodiment exemplifies an apparatus and a method for embodying the technical idea of the invention. The drawings are schematic or conceptual. Dimensions, ratios, etc. of each drawing are not necessarily the same as those in reality. The technical idea of the present invention is not specified by the shape, structure, arrangement, etc. of the components. Also, in the following description, components having substantially the same function and configuration are denoted by the same reference numerals.

[0009] <1> Configuration of Wireless System 1 <1-1> Overall Configuration of Wireless System 1 FIG. 1 shows an example of the configuration of a wireless system 1 according to an embodiment. As shown in FIG. 1, the wireless system 1 includes, for example, a base station 10, a terminal 20, and a server 30.

[0010] The base station 10 is connected to the network NW and used as an access point for a wireless LAN. For example, the base station 10 can wirelessly distribute the data received from the network NW to the terminal 20. Also, the base station 10 can be connected to the terminal 20 using one type of band or multiple types of bands. In this specification, the wireless connection using multiple types of bands between the base station 10 and the terminal 20 is referred to as "multi-link". The communication between the base station 10 and the terminal 20 is based on, for example, the IEEE802.11 standard.

[0011] The terminal 20 is a wireless terminal such as a smartphone or a tablet PC, for example. The terminal 20 can transmit and receive data to and from the server 30 on the network NW via the wirelessly connected base station 10. Note that the terminal 20 may be other electronic devices such as a desktop computer or a laptop computer. The terminal 20 only needs to be a device that can communicate with at least the base station 10 and execute the operations described later.

[0012] The server 30 can hold various information and holds, for example, content data targeted at the terminal 20. The server 30 is connected to the network NW by wire, for example, and is configured to be able to communicate with the base station 10 via the network NW. Note that the server 30 only needs to be able to communicate with at least the base station 10. That is, the communication between the base station 10 and the server 30 may be wired or wireless.

[0013] In the wireless system 1 according to the embodiment, the data communication between the base station 10 and the terminal 20 is based on the OSI (Open Systems Interconnection) reference model. In the OSI reference model, the communication function is divided into seven layers (Layer 1: Physical Layer, Layer 2: Data Link Layer, Layer 3: Network Layer, Layer 4: Transport Layer, Layer 5: Session Layer, Layer 6: Presentation Layer, Layer 7: Application Layer).

[0014] The data link layer includes, for example, an LLC (Logical Link Control) layer and a MAC (Media Access Control) layer. The LLC layer adds, for example, a DSAP (Destination Service Access Point) header, an SSAP (Source Service Access Point) header, etc. to the data input from the upper application to form an LLC packet. The MAC layer adds a MAC header to the LLC packet, for example, to form a MAC frame.

[0015] (Regarding the frequency bands used for wireless communication) FIG. 2 shows an example of the frequency bands used for wireless communication in the wireless system 1 according to the embodiment. As shown in FIG. 2, in wireless communication, for example, the 2.4 GHz band, the 5 GHz band, and the 6 GHz band are used. And each frequency band includes a plurality of channels respectively. In this example, each of the 2.4 GHz band, the 5 GHz band, and the 6 GHz band includes at least three channels CH1, CH2, and CH3. Communication using each channel CH is realized by the STA function described later.

[0016] Note that the wireless system 1 may use frequency bands other than the 2.4 GHz band, the 5 GHz band, and the 6 GHz band for wireless communication. It is sufficient that at least one channel CH is set for each frequency band. For multi-link, channels CH in the same frequency band may be used, or channels CH in different frequency bands may be used.

[0017] (Regarding the format of the wireless frame) FIG. 3 shows a specific example of the format of a radio frame used in the communication between the base station 10 and the terminal 20 in the radio system 1 according to the embodiment. As shown in FIG. 3, the radio frame includes, for example, a Frame Control field, a Duration field, an Address1 field, an Address2 field, an Address3 field, a Sequence Control field, other control information fields, a Frame Body field, and an FCS (Frame Check Sequence) field.

[0018] The Frame Control field to other control information fields correspond to, for example, the MAC header included in the MAC frame. The Frame Body field corresponds to, for example, the MAC payload included in the MAC frame. The FCS field stores an error detection code for the MAC header and the Frame Body field and is used to determine the presence or absence of an error in the radio frame.

[0019] The Frame Control field indicates various control information and includes, for example, a Type value, a Subtype value, a To DS (To Distribution System) value, and a From DS value. The Type value indicates the frame type of the radio frame. For example, the Type value "00" indicates that the radio frame is a management frame. The Type value "01" indicates that the radio frame is a control frame. The Type value "10" indicates that the radio frame is a data frame.

[0020] The content of a wireless frame varies depending on the combination of the Type value and the Subtype value. For example, "00 / 1000 (Type value / Subtype value)" indicates that the wireless frame is a beacon signal. The meanings of the To DS value and the From DS value differ depending on their combination. For example, "00 (To DS / From DS)" indicates that the data is between terminals within the same IBSS (Independent Basic Service Set). "10" indicates that the data frame is directed from the outside to the DS (Distribution System). "01" indicates that the data frame is directed out of the DS. "11" is used when configuring a mesh network.

[0021] The Duration field indicates the scheduled period for using the wireless link. The multiple Address fields indicate the BSSID, source address, destination address, address of the sender terminal, address of the receiver terminal, etc. The Sequence Control field indicates the sequence number of the MAC frame and the fragment number for fragmentation. The other control information field includes, for example, traffic type (TID) information. The TID information may be inserted at other positions within the wireless frame. The Frame Body field contains information corresponding to the type of the frame. For example, when corresponding to a data frame, the Frame Body field stores data.

[0022] <1-2>Configuration of Base Station 10 FIG. 4 shows an example of the configuration of the base station 10 included in the wireless system 1 according to the embodiment. As shown in FIG. 4, the base station 10 includes, for example, a CPU (Central Processing Unit) 11, a ROM (Read Only Memory) 12, a RAM (Random Access Memory) 13, a wireless communication module 14, and a wired communication module 15.

[0023] The CPU 11 is a circuit capable of executing various programs and controls the overall operation of the base station 10. The ROM 12 is a non-volatile semiconductor memory that holds programs, control data, etc. for controlling the base station 10. The RAM 13 is, for example, a volatile semiconductor memory and is used as a working area for the CPU 11. The wireless communication module 14 is a circuit used for transmitting and receiving data via wireless signals and is connected to an antenna. Also, the wireless communication module 14 includes, for example, a plurality of communication modules each corresponding to a plurality of frequency bands. The wired communication module 15 is a circuit used for transmitting and receiving data via wired signals and is connected to the network NW.

[0024] FIG. 5 shows an example of the functional configuration of the base station 10 included in the wireless system 1 according to the embodiment. As shown in FIG. 5, the base station 10 includes, for example, a data processing unit 110, a link management unit 120, and wireless signal processing units 130, 140, and 150. The processing of the data processing unit 110, the link management unit 120, and the wireless signal processing units 130, 140, and 150 is realized, for example, by the CPU 11 and the wireless communication module 14.

[0025] The data processing unit 110 can execute LLC layer processing and upper layer (layers 3 to 7) processing on the input data. For example, the data processing unit 110 outputs the data input from the server 30 via the network NW to the link management unit 120. Also, the data processing unit 110 transmits the data input from the link management unit 120 to the server 30 via the network NW.

[0026] The link management unit 120 executes, for example, a part of the MAC layer processing on the input data. Also, the link management unit 120 manages the link with the terminal 20 based on notifications from the radio signal processing units 130, 140, and 150. The link management unit 120 includes link management information 121. The link management information 121 is stored, for example, in the RAM 13 and includes information on the terminal 20 wirelessly connected to the base station 10. Further, the link management unit 120 includes an association processing unit 122 and an authentication processing unit 123. When the association processing unit 122 receives a connection request from the terminal 20 via any of the radio signal processing units 130, 140, and 150, it executes a protocol related to association. The authentication processing unit 123 executes a protocol related to authentication following the connection request.

[0027] Each of the radio signal processing units 130, 140, and 150 transmits and receives data between the base station 10 and the terminal 20 using wireless communication. For example, each of the radio signal processing units 130, 140, and 150 adds a preamble, a PHY header, etc. to the data input from the link management unit 120 to create a wireless frame. Then, each of the radio signal processing units 130, 140, and 150 converts the wireless frame into a wireless signal and distributes the wireless signal via the antenna of the base station 10. Also, each of the radio signal processing units 130, 140, and 150 converts the wireless signal received via the antenna of the base station 10 into a wireless frame. Then, each of the radio signal processing units 130, 140, and 150 outputs the data included in the wireless frame to the link management unit 120.

[0028] In this way, each of the radio signal processing units 130, 140, and 150 can execute, for example, a part of the MAC layer processing and the first layer processing on the input data or radio signal. For example, the radio signal processing unit 130 handles radio signals in the 2.4 GHz band. The radio signal processing unit 140 handles radio signals in the 5 GHz band. The radio signal processing unit 150 handles radio signals in the 6 GHz band. The radio signal processing units 130, 140, and 150 may or may not share the antennas of the base station 10.

[0029] <1-3>Configuration of the terminal 20 FIG. 6 shows an example of the configuration of the terminal 20 included in the wireless system 1 according to the embodiment. As shown in FIG. 6, the terminal 20 includes, for example, a CPU 21, a ROM 22, a RAM 23, a wireless communication module 24, a display 25, and a storage 26.

[0030] The CPU 21 is a circuit capable of executing various programs and controls the overall operation of the terminal 20. The ROM 22 is a non-volatile semiconductor memory and holds programs and control data for controlling the terminal 20. The RAM 23 is, for example, a volatile semiconductor memory and is used as a work area for the CPU 21. The wireless communication module 24 is a circuit used for transmitting and receiving data by radio signals and is connected to an antenna. Further, the wireless communication module 24 includes, for example, a plurality of communication modules corresponding to a plurality of frequency bands respectively. The display 25 displays, for example, a GUI (Graphical User Interface) corresponding to application software. The display 25 may have a function as an input interface of the terminal 20. The storage 26 is a non-volatile storage device and holds, for example, the system software of the terminal 20. Note that the terminal 20 may not include a display. For example, in an IoT terminal, the display 25 may be omitted.

[0031] FIG. 7 shows an example of the functional configuration of the terminal 20 included in the wireless system 1 according to the embodiment. As shown in FIG. 7, the terminal 20 includes, for example, a data processing unit 210, a link management unit 220, wireless signal processing units 230, 240, and 250, and an application execution unit 260. The processing of the data processing unit 210, the link management unit 220, and the wireless signal processing units 230, 240, and 250 is realized by, for example, the CPU 21 and the wireless communication module 24.

[0032] The data processing unit 210 can execute LLC layer processing and upper layer (layers 3 to 7) processing on the input data. For example, the data processing unit 210 outputs the data input from the application execution unit 260 to the link management unit 220. Also, the data processing unit 210 outputs the data input from the link management unit 220 to the application execution unit 260.

[0033] The link management unit 220 executes, for example, a part of the MAC layer processing on the input data. Also, the link management unit 220 manages the link with the base station 10 based on notifications from the wireless signal processing units 230, 240, and 250. The link management unit 220 includes link management information 221. The link management information 221 is stored in, for example, the RAM 23 and includes information on the base station 10 wirelessly connected to the terminal 20. Also, the link management unit 220 includes an association processing unit 222 and an authentication processing unit 223. The association processing unit 222 executes a protocol related to association when receiving a connection response from the base station 10 via any of the wireless signal processing units 230, 240, and 250. The authentication processing unit 223 executes a protocol related to authentication following the connection response.

[0034] Each of the radio signal processing units 230, 240, and 250 transmits and receives data between the base station 10 and the terminal 20 using wireless communication. For example, each of the radio signal processing units 230, 240, and 250 adds a preamble, a PHY header, etc. to the data input from the link management unit 220 to create a radio frame. Then, each of the radio signal processing units 230, 240, and 250 converts the radio frame into a radio signal and distributes the radio signal via the antenna of the terminal 20. Also, each of the radio signal processing units 230, 240, and 250 converts the radio signal received via the antenna of the terminal 20 into a radio frame. Then, each of the radio signal processing units 230, 240, and 250 outputs the data included in the radio frame to the link management unit 220.

[0035] In this way, each of the radio signal processing units 230, 240, and 250 can perform, for example, part of the MAC layer processing and the layer 1 processing on the input data or radio signal. For example, the radio signal processing unit 230 handles radio signals in the 2.4 GHz band. The radio signal processing unit 240 handles radio signals in the 5 GHz band. The radio signal processing unit 250 handles radio signals in the 6 GHz band. The radio signal processing units 230, 240, and 250 may or may not share the antenna of the terminal 20.

[0036] The application execution unit 260 executes an application that can utilize the data input from the data processing unit 210. For example, the application execution unit 260 can display application information on the display 25. Also, the application execution unit 260 can operate based on the operation of the input interface.

[0037] In the wireless system 1 according to the embodiment described above, the radio signal processing units 130, 140, and 150 of the base station 10 are each configured to be connectable to the radio signal processing units 230, 240, and 250 of the terminal 20. That is, the radio signal processing units 130 and 230 can be wirelessly connected using the 2.4 GHz band. The radio signal processing units 140 and 240 can be wirelessly connected using the 5 GHz band. The radio signal processing units 150 and 250 can be wirelessly connected using the 6 GHz band. In this specification, each radio signal processing unit may be called a "STA function". That is, the wireless system 1 according to the embodiment includes a plurality of STA functions.

[0038] <1-4>Regarding the link management unit 120 FIG. 8 shows the details of the channel access function in the link management unit 120 of the base station 10 included in the wireless system 1 according to the embodiment. Note that the function of the link management unit 220 of the terminal 20 is the same as that of the link management unit 120 of the base station 10, for example, and thus the description thereof is omitted. As shown in FIG. 8, the link management unit 120 includes, for example, a data categorization unit 124, transmission queues 125A, 125B, 125C, 125D, and 125E, CSMA / CA (Carrier Sense Multiple Access with Collision Avoidance) execution units 126A, 126B, 126C, 126D, and 126E, and a data collision management unit 127.

[0039] The data categorization unit 124 categorizes the data input from the data processing unit 110. As data categories, for example, "LL (Low Latency)", "VO (Voice)", "VI (Video)", "BE (Best Effort)", and "BK (Background)" are set. LL is applied to data that requires low latency. Therefore, it is preferable that the LL data is processed with priority over any of the VO, VI, BE, and BK data.

[0040] Then, the data categorization unit 124 inputs the categorized data into any one of the transmission queues 125A, 125B, 125C, 125D, and 125E. Specifically, the LL data is input into the transmission queue 125A. The VO data is input into the transmission queue 125B. The VI data is input into the transmission queue 125C. The BE data is input into the transmission queue 125D. The BK data is input into the transmission queue 125E. Then, the data of each input category is stored in any one of the corresponding transmission queues 125A to 125E.

[0041] Each of the CSMA / CA execution units 126A, 126B, 126C, 126D, and 126E waits for transmission for a time specified by preset access parameters while confirming by carrier sense that there is no transmission of wireless signals by other terminals or the like in CSMA / CA. Then, the CSMA / CA execution units 126A, 126B, 126C, 126D, and 126E each retrieve data from the transmission queues 125A, 125B, 125C, 125D, and 125E, and output the retrieved data to at least one of the wireless signal processing units 130, 140, and 150 via the data collision management unit 127. Then, the wireless signal including the data is transmitted by the wireless signal processing unit (STA function) that has acquired the transmission right by CSMA / CA.

[0042] The CSMA / CA execution unit 126A executes CSMA / CA for the LL data held in the transmission queue 125A. The CSMA / CA execution unit 126B executes CSMA / CA for the VO data held in the transmission queue 125B. The CSMA / CA execution unit 126C executes CSMA / CA for the VI data held in the transmission queue 125C. The CSMA / CA execution unit 126D executes CSMA / CA for the BE data held in the transmission queue 125D. The CSMA / CA execution unit 126E executes CSMA / CA for the BK data held in the transmission queue 125E.

[0043] Still, the access parameters are assigned such that the transmission of the wireless signal is prioritized in the order of, for example, LL, VO, VI, BE, and BK. The access parameters include, for example, CWmin, CWmax, AIFS, and TXOPLimit. CWmin and CWmax respectively indicate the minimum and maximum values of the contention window, which is the transmission waiting time for collision avoidance. AIFS (Arbitration Inter Frame Space) indicates the fixed transmission waiting time set for each access category for collision avoidance control with a priority control function. TXOPLimit indicates the upper limit value of TXOP (Transmission Opportunity) corresponding to the channel occupancy time. For example, for transmission queue 125, the shorter CWmin and CWmax are, the easier it is to obtain the transmission right. The priority of transmission queue 125 becomes higher as AIFS becomes smaller. The amount of data transmitted with one transmission right increases as the value of TXOPLimit becomes larger.

[0044] The data collision management unit 127 prevents data collisions when a plurality of CSMA / CA execution units 126 acquire the transmission right with the same STA function. Specifically, the data collision management unit 127 adjusts the transmission timing of data whose categories are different and whose transmission right is acquired with the same STA function, and transmits the data to the STA function starting from the data in the category with the higher priority. For example, there may be a case where an STA function that has acquired the transmission right by CSMA / CA of the LL transmission queue 125A becomes the same as an STA function that has acquired the transmission right by CSMA / CA of any of the other transmission queues 125B to 125E. In this case, the data collision management unit 127 preferentially transmits the data stored in the transmission queue 125A to the STA function. Similarly, in other combinations of the transmission queues 125, the data is transmitted in the order based on the priority set for the category. This prevents collisions between data assigned for transmission to the same STA function.

[0045] In the embodiment, a form in which the link management unit implements the channel access function is described, but each STA function may implement the channel access function. When the link management unit implements the channel access function, each STA function detects the state (idle / busy) of the radio channel in the corresponding link, and the link management unit determines whether data can be transmitted (such as which link to use for transmission). On the other hand, when each STA function implements the channel access function, each STA function may independently perform carrier sensing and transmit data. At this time, channel access when a plurality of links are used simultaneously may be executed by sharing access parameters through communication between a plurality of STA functions, or may be executed by sharing access parameters by the link management unit. The base station 10 and the terminal 20 can use a plurality of links simultaneously by transmitting data based on common access parameters among a plurality of STA functions.

[0046] <1-5>Regarding the link management information 121 FIG. 9 shows an example of the link management information 121 in the wireless system 1 according to the embodiment. Since the link management information 221 of the terminal 20 has information similar to the link management information 121 of the base station 10, the description thereof is omitted. As shown in FIG. 9, the link management information 121 includes information such as, for example, STA function, frequency band, channel ID, link destination ID, multi-link, and TID.

[0047] In this example, "STA1" corresponds to the STA function using the 6 GHz frequency band, that is, the radio signal processing unit 150 or 250. "STA2" corresponds to the STA function using the 5 GHz frequency band, that is, the radio signal processing unit 140 or 240. "STA3" corresponds to the STA function using the 2.4 GHz frequency band, that is, the radio signal processing unit 130 or 230. Hereinafter, STA1, STA2, and STA3 are also referred to as link #1, link #2, and link #3, respectively.

[0048] The channel ID corresponds to the identifier of the channel being used in the set frequency band. The link destination ID corresponds to the identifier of terminal 20 in link management information 121 and to the identifier of base station 10 in link management information 221. In this example, a multi-link using STA1, STA2, and STA3 is established. When a multi-link is established, each of link management units 120 and 220 transmits the data input from the upper layer using at least one link of the STA functions associated with the multi-link.

[0049] Base station 10 sets one of the plurality of STA functions as an anchor link. In this example, STA1 is set as the anchor link. The anchor link is set by link management unit 120 of base station 10. In addition to transmitting and receiving the assigned data, the anchor link transmits and receives control information related to the operation of the multi-link. Note that the combination of links constituting the multi-link may be different among the plurality of terminals 20 each establishing a multi-link with base station 10.

[0050] "TID" in link management information 121 indicates the association between the STA function and the TID information. Each STA function transmits and receives data corresponding to the assigned TID information. For example, each of TID#1 to 4 corresponds to one of LL, VO, VI, BE, and BK. One traffic, that is, one TID information, may be associated with one STA function or may be associated with a plurality of STA functions. In this example, TID#1 is assigned to both STA1 and STA2. TID#2 is assigned to STA1. TID#3 is assigned to STA2. TID#4 is assigned to STA3.

[0051] A traffic flow corresponding to the association between such traffic and the STA function is preset when setting up a multi-link between the base station 10 and the terminal 20. For example, the link management unit 220 of the terminal 20 determines the association between the traffic and the STA function and requests the link management unit 120 of the base station 10. Then, the base station 10 responds to the request, and the association between the traffic and the STA function is determined.

[0052] In addition, the traffic is set to be evenly distributed among a plurality of links constituting the multi-link, for example. However, the present invention is not limited to this, and traffic of similar types (priority / non-priority, etc.) may be concentrated on one link constituting the multi-link. As for the association between the STA function and the traffic, for example, voice is associated with the 2.4 GHz frequency band, and video is associated with 5G. Thus, it is preferable that the frequency used for transmission and reception is allocated according to the type of information to be handled and the data capacity.

[0053] <2> Operations of the wireless system 1 Hereinafter, an example of various operations related to the multi-link of the wireless system 1 according to the embodiment will be described. In the following description, for the sake of simplicity, the STA1, STA2, and STA3 of the base station 10 are also referred to as "access point AP". The fact that the STA1, STA2, and STA3 of the terminal 20 transmit wireless signals to the access point AP corresponds to transmitting wireless signals to the STA1, STA2, and STA3 of the base station 10, respectively. When STA1, STA2, and STA3 are each described alone, these indicate the STA functions of the terminal 20.

[0054] <2-1> Multi-link processing FIG. 10 shows an example of the flow of multi-link processing in the wireless system 1 according to the embodiment. As shown in FIG. 10, in multi-link processing, for example, the processes of steps S10 to S16 are executed in order. Hereinafter, the processes of steps S10 to S16 will be described by taking as an example the case where a multi-link is formed using three STA functions.

[0055] In the process of step S10, the terminal 20 transmits a probe request to the base station 10. The probe request is a signal for checking whether the base station 10 exists around the terminal 20. The Frame Control field of the probe request includes, for example, "00 / 0100 (Type value / Subtype value)". When the base station 10 receives the probe request, it executes the process of step S11.

[0056] In the process of step S11, the base station 10 transmits a probe response to the terminal 20. The probe response is a signal used by the base station 10 for responding to the probe request from the terminal 20. The Frame Control field of the probe response includes, for example, "00 / 0101 (Type value / Subtype value)". When the terminal 20 receives the probe request, it executes the process of step S12.

[0057] In the process of step S12, the terminal 20 transmits a multi-link association request to the base station 10 via at least one STA function. The multi-link association request is a signal for requesting the establishment of a multi-link from the terminal 20 to the base station 10. For example, the multi-link association request is generated by the link management unit 220 of the terminal 20. The Frame Control field of the multi-link association request includes, for example, "00 / xxxx (Type value / Subtype value (xxxx is a predetermined value))". When the link management unit 120 of the base station 10 receives the multi-link association request, it executes the process of step S13.

[0058] In the process of step S13, the link management unit 120 of the base station 10 executes multi-link association processing using one STA function. Specifically, first, the base station 10 executes association processing of the first STA function with the terminal 20. Then, when a wireless connection (link) is established in the first STA function, the link management unit 120 of the base station 10 uses the first STA function in which the link is established to execute association processing of the second STA function and association processing of the third STA function. That is, the STA function in which the link is established is used for the association processing of the STA function in which the link is not established. When the association processing of at least two STA functions is completed, the base station 10 establishes a multi-link and executes the process of step S14.

[0059] In the process of step S14, the link management unit 120 of the base station 10 updates the link management information 121. Note that in this example, the process of step S14 is executed after two links are established, but the link management information 121 may be updated each time the link state is updated, or may be updated when the multi-link is established. When the multi-link is established and the link management information is updated, the base station 10 executes the process of step S15.

[0060] In the process of step S15, the base station 10 transmits a multi-link establishment response to the terminal 20. The multi-link establishment response is a signal used by the base station 10 for a response to a multi-link request from the terminal 20. The Frame Control field of the multi-link association request includes, for example, "00 / 0001 (Type value / Subtype value)". The link management unit 220 of the terminal 20 recognizes that the multi-link with the base station 10 is established based on receiving the multi-link establishment response. When the terminal 20 receives the multi-link establishment response, it executes the process of step S16.

[0061] In the process of step S16, the link management unit 220 of the terminal 20 updates the link management information 221. That is, the terminal 20 records in the link management information 221 that the multi-link with the base station 10 has been established. Thereby, the multi-link processing in the wireless system 1 according to the embodiment is completed, and data communication using the multi-link becomes possible between the base station 10 and the terminal 20.

[0062] In addition, the wireless system 1 according to the embodiment may establish a multi-link when establishing a link in the first STA function. In this case, before the multi-link association request in step S12, the terminal 20 receives a beacon signal related to the multi-link from the base station 10. Hereinafter, this operation will be described with reference to FIGS. 11 and 12.

[0063] FIG. 11 shows an example of a method for outputting a beacon signal in the base station 10 included in the wireless system 1 according to the embodiment. In this example, link #1 among links #1 to #3 is set as the anchor link. As shown in FIG. 11, the base station 10 intermittently transmits the beacon signal using link #1 set as the anchor link. On the other hand, the transmission of the beacon signal by links #2 and #3 that are not set as the anchor link is omitted. The beacon signal may be transmitted using a link that is not set as the anchor link, as long as it is transmitted using at least the anchor link.

[0064] FIG. 12 shows a specific example of a beacon signal including multi-link capability information in the wireless system 1 according to the embodiment. As shown in FIG. 12, the beacon signal includes, for example, multi-link capability information, operation information of link #1, operation information of link #2, and operation information of link #3. These information are generated by the link management unit 120 of the base station 10.

[0065] The multi-link capability information indicates whether the base station 10 is multi-link capable. For example, when the multi-link capability information is "0", it indicates that multi-link is not possible. When the multi-link capability information is "1", it indicates that multi-link is possible. The link operation information (operational parameters) indicates the parameters for data transmission and the like in the links that can be used for multi-link. For example, the operation information of link #1 indicates the access parameters of EDCA (Enhanced Distributed Channel Access) for performing transmission control in the link.

[0066] When the terminal 20 receives the beacon signal described with reference to FIG. 12, it checks the multi-link capability information and the operation information of each link that is the target of multi-link from the beacon signal. Then, when making a multi-link association request, the link management unit 220 of the terminal 20 notifies the link management unit 120 of the base station 10 of information such as the links that are the target of multi-link. Thereby, the link management unit 120 of the base station 10 can collectively execute the association of the plurality of links designated by the link management unit 220 of the terminal 20 and establish a multi-link with the terminal 20.

[0067] In addition, when the above-described beacon signal is transmitted only on the anchor link, the beacon signal may not have a field indicating the anchor link. On the other hand, when the beacon signal is transmitted on the anchor link and other links, the beacon signal may have a field indicating the anchor link and a field indicating other links. Further, the base station 10 may add the information included in the above-described beacon signal to the probe response. In this case, the link management unit 220 of the terminal 20 can transmit a multi-link association request designating the link to be used to the base station 10 without receiving the beacon signal. Also, the base station 10 and the terminal 20 may execute an authentication process when establishing a multi-link.

[0068] <2-2>Data Transfer during Multi-Link FIG. 13 shows an example of a data transmission method during multi-link in the base station 10 included in the wireless system 1 according to the embodiment. As shown in FIG. 13, when the base station 10 acquires data from the upper layer, it sequentially executes the processes of steps S20 to S22. Hereinafter, the processes of steps S20 to S22 will be described.

[0069] In the process of step S20, the link management unit 120 acquires TID information corresponding to the data. In other words, the link management unit 120 associates the data with the TID by referring to control information such as a header added to the data acquired from the upper layer, for example.

[0070] In the process of step S21, the link management unit 120 acquires the STA function corresponding to the confirmed TID information. At this time, the link management unit 120 checks the association between the TID information and the STA function by referring to the link management information 121. Note that, in the process of step S21, the number of STA functions acquired by the link management unit 120 may be one or more.

[0071] In the process of step S22, the link management unit 120 outputs the data to the acquired STA function. When one STA function is associated with the output data (traffic), the data is serially transmitted using one STA function. On the other hand, when a plurality of STA functions are associated with the traffic, the data is parallelly transmitted using a plurality of STA functions.

[0072] When one traffic is transmitted in parallel, data distribution and rearrangement are performed between the link management unit 120 of the base station 10 and the link management unit 220 of the terminal 20. Data distribution is performed by the link management unit on the transmission side, and data rearrangement is performed by the link management unit on the reception side. For example, the link management unit on the transmission side adds a flag indicating multi-link and an identification number to the radio frame. The link management unit on the reception side performs data rearrangement based on the added flag and identification number.

[0073] Also, in the radio system 1 according to the embodiment, when the link management unit receives a plurality of data from the upper layer, it may perform aggregation by combining the received plurality of data. Aggregation in multi-link may be used as an optional function whose execution can be selected by the user.

[0074] <2-3>Multi-link Power Saving In the radio system 1 according to the embodiment, a plurality of types of operation modes are prepared for each STA function. Examples of the operation modes of the STA function include an active mode, an intermittent operation mode, and an operation suspension mode. The active mode corresponds to a state in which the STA function of the terminal 20 can transmit and receive radio signals at any time by maintaining the Awake state. The intermittent operation mode corresponds to a state in which the STA function of the terminal 20 operates intermittently by repeating the Awake state and the Doze state. The operation suspension mode corresponds to a state in which the STA function of the terminal 20 cannot transmit and receive radio signals by maintaining the Doze state.

[0075] In the present specification, the "Awake state" corresponds to a state in which wireless signals can be transmitted and received. The Dose state corresponds to a state in which wireless signals cannot be transmitted and received. In the "Doze state", the power supply to the circuit related to the STA function is appropriately cut off. Therefore, the power consumption of the STA function decreases in the order of the active mode, the intermittent operation mode, and the operation suspension mode. Note that although the base station 10 or the terminal 20 can be used for communication, there may be links that are not included in the link set of the multi-link between them (Disabled links). Hereinafter, for the sake of simplicity of explanation, a link in the active mode or the intermittent operation mode, that is, a communicable link, is referred to as an "STA function (link) in the Awake state". A link in the operation suspension mode, that is, a power-saving state link that cannot communicate, is referred to as an "STA function (link) in the Dose state".

[0076] In the multi-link in the wireless system 1 according to the embodiment, the anchor link is set to, for example, either the active mode or the intermittent operation mode. On the other hand, the links other than the anchor link are set to any one of the active mode, the intermittent operation mode, and the operation suspension mode. For example, the terminal 20 can operate in a power-saving manner by setting a link other than the anchor link to the operation suspension mode during multi-link.

[0077] Hereinafter, the state of the multi-link in which the anchor link is set to the intermittent operation mode and the links other than the anchor link are set to the operation suspension mode is referred to as "multi-link power save". Note that when a link other than the anchor link also receives a beacon signal in addition to the anchor link during multi-link power save, the link is set to the active mode or the intermittent operation mode.

[0078] FIG. 14 shows an example of changes in the link management information 121 when multi-link power save is applied in the wireless system 1 according to the embodiment. The upper and lower tables in FIG. 14 correspond to the case where multi-link power save is not applied and the case where it is applied, respectively. As shown in FIG. 14, the link management information 121 further includes operation mode information.

[0079] As shown in the upper part of FIG. 14, when multi-link power save is not applied, for example, the operation modes of STA1, STA2, and STA3 are each set to the active mode. Other parameters of the link management information 121 when multi-link power save is not applied in this example are the same as the link management information 121 shown in FIG. 9.

[0080] As shown in the lower part of FIG. 14, when multi-link power save is applied, for example, the operation modes of STA1, STA2, and STA3 are set to the intermittent operation mode, the operation suspension mode, and the operation suspension mode, respectively. Other parameters of the link management information 121 when multi-link power save is applied are the same as those when multi-link power save is not applied.

[0081] The on / off of multi-link power save is applied by a Doze transition notification signal (“disable”) and an Awake transition request signal (“enable”), respectively. For example, after multi-link is set, when the terminal 20 sends a Doze transition notification signal to the base station 10, the terminal 20 is set to multi-link power save. When the base station 10 sends an Awake transition request signal to the terminal 20 in the state where the terminal 20 is set to multi-link power save, the setting of multi-link power save of the terminal 20 is cancelled.

[0082] The Awake transition request signal and the Doze transition notification signal may be transmitted from either the base station 10 or the terminal 20. The transmission of the Awake transition request signal is executed using the anchor link or other active links. The transmission of the Doze transition notification signal is executed using the anchor link or a link to be stopped (a link that transitions to the operation suspension mode). Also, the multi-link power saving may be applied when the multi-link is established. The multi-link power saving only needs to be more power-saving than at least when the multi-link power saving is not applied. For example, in the multi-link power saving, the anchor link may be set to the active mode and the other links may be set to the operation suspension mode.

[0083] (Operation of the base station 10 during multi-link power saving) FIG. 15 shows an example of the operation during multi-link of the base station 10 included in the wireless system 1 according to the embodiment. As shown in FIG. 15, when there is buffer data, the link management unit 120 of the base station 10 checks the state of the multi-link (step S30). The buffer data is data received by the base station 10 via the network NW, and indicates, for example, the data accumulated in the transmission queue 125. Then, the link management unit 120 of the base station 10 checks whether the link associated with the buffer data is in the intermittent operation mode or the operation suspension mode (step S31).

[0084] When the link associated with the buffer data is in the intermittent operation mode or the operation suspension mode (step S31, YES), the link management unit 120 of the base station 10 transmits a beacon signal including a PVB (Partial Virtual Bitmap) for each TID to the terminal 20 (step S32). The creation of the beacon signal may be executed by the link management unit 120 or by the STA function of the anchor link. When the link associated with the buffer data is not in the intermittent operation mode or the operation suspension mode (step S31, NO), the link management unit 120 of the base station 10 transmits the data to the destination terminal 20 (step S33).

[0085] FIG. 16 shows a specific example of a beacon signal including a PVB in the wireless system 1 according to the embodiment. As shown in FIG. 16, the beacon signal includes, for example, a terminal identifier and PVBs of a plurality of TIDs.

[0086] The terminal identifier includes, for example, an association identifier AID (Association Identifier) between the base station 10 and the terminal 20. The PVBs of the plurality of TIDs include, for example, a PVB of TID#1, a PVB of TID#2, a PVB of TID#3, and a PVB of TID#4. For example, when the PVB of TID#1 is "0", it indicates that the traffic of TID#1 is not accumulated. When the PVB of TID#1 is "1", it indicates that the traffic of TID#1 is accumulated. Note that the combination of the bit assigned to the PVB and the presence or absence of traffic accumulation can be arbitrarily changed. Also, the number of PVBs of the plurality of TIDs included in the beacon signal can be changed based on the set number of TIDs.

[0087] (Operation of Terminal 20 during Multi-Link Power Save) FIG. 17 shows an example of the operation of the terminal 20 included in the wireless system 1 according to the embodiment during multi-link power saving. As shown in FIG. 17, during multi-link power saving, for example, the anchor link of the terminal 20 operating in the intermittent operation mode receives a beacon signal (step S40). Then, the link management unit 220 of the terminal 20 checks the AID included in the beacon signal and the PVB of each TID to check whether there is buffer data addressed to its own station (step S41).

[0088] If there is no buffer data addressed to its own station (step S41, NO), the terminal 20 ends this operation. If there is buffer data addressed to its own station (step S41, YES), the link management unit 220 of the terminal 20 checks whether the link associated with the buffer data is in the Awake state, that is, whether it is in the active mode or the intermittent operation mode (step S42).

[0089] If the link associated with the buffer data is in the Awake state (step S42, YES), the link management unit 220 of the terminal 20 requests the base station 10 to transmit data (step S43). If the link associated with the buffer data is not in the Awake state (step S42, NO), the link management unit 220 of the terminal 20 first wakes up the link associated with the buffer data, that is, transitions it from the Doze state to the Awake state. After that, the link management unit 220 of the terminal 20 requests the base station 10 to transmit data (step S43).

[0090] The terminal 20 executes the operations described above each time the anchor link receives a beacon signal. When there is no buffer data for the link that has been woken up, the link management unit 220 of the terminal 20 transitions the link back to the Doze state. Note that the timing at which the link management unit 220 of the terminal 20 transitions the woken-up link to the Doze state can be set to any timing. For example, the timing at which the link management unit 220 of the terminal 20 transitions the woken-up link to the Doze state may be the timing when the buffer data for the link destination has disappeared, or may be the timing when a predetermined time has elapsed after the buffer data for the link destination has disappeared.

[0091] (Specific Example of Start Operation of Multi-Link Power Save) FIG. 18 shows an example of the flow of the start operation of multi-link power save in the wireless system 1 according to the embodiment. As shown in FIG. 18, at the start of this operation, each of STA1, STA2, and STA3 is in an active state. The access point AP transmits a beacon signal to STA1 of the terminal 20, that is, the anchor link (step S50). This beacon signal includes information indicating that, for example, the traffic of each of STA1, STA2, and STA3 is empty.

[0092] In response to, for example, the traffic being empty, STA1 of the terminal 20 transmits a wireless signal notifying the start of multi-link power save to the access point AP (step S51). The data frame of the wireless signal notifying the start of multi-link power save includes, for example, a PM (Power Management) bit in which “1” is stored. The access point AP that has received the signal “PM = 1” transmits a wireless signal (Data ACK) notifying the terminal 20 that the signal has been received to STA1 of the terminal 20 (step S52).

[0093] When the link management unit 220 of terminal 20 receives a Data ACK for the data frame containing "PM = 1" sent by STA1 of terminal 20, it transitions STA1 (anchor link) to the intermittent operation mode (Awake state) and STA2 and STA3 to the operation suspension mode (Doze state) (step S53). Thereby, the total power consumption of STA1, STA2, and STA3 constituting the multi-link becomes lower than before the use of multi-link power save. Note that in the process of step S53, it is sufficient that there is at least one STA function set to the Doze state within the plurality of STA functions constituting the multi-link.

[0094] After transmitting a Data ACK for receiving "PM = 1", the access point AP transmits a beacon signal including PVB to STA1 (anchor link) of terminal 20 (step S54). At this time, STA1 in the Awake state can receive the beacon signal. On the other hand, STA2 and STA3 in the Doze state maintain a lower power consumption state than STA1 without receiving the beacon signal.

[0095] As described above, the terminal 20 in the wireless system 1 according to the embodiment transitions to multi-link power save according to the traffic state and suppresses the power consumption of the multi-link. Then, based on the fact that the terminal 20 has transitioned to multi-link power save, the base station 10 intermittently transmits a beacon signal including PVB for notifying the buffer status of data using the anchor link in the Awake state. Details of the communication method between the base station 10 and the terminal 20 during multi-link power save will be described later.

[0096] (Specific example of the end operation of multi-link power save) FIG. 19 shows an example of the flow of the multi-link power save end operation in the wireless system 1 according to the embodiment. As shown in FIG. 19, at the start of this operation, STA1 is in the Awake state, and STA2 and STA3 are in the Doze state. The access point AP transmits a beacon signal to STA1 of the terminal 20, that is, the anchor link (step S60). This beacon signal includes, for example, information requesting the end of multi-link power save to the terminal 20.

[0097] In response to receiving the beacon signal, STA1 of the terminal 20 transmits a wireless signal notifying the end of multi-link power save to the access point AP (step S61). The data frame of the wireless signal notifying the end of multi-link power save includes, for example, a PM bit in which “0” is stored. The access point AP that has received the signal “PM = 0” transmits a wireless signal (Data ACK) notifying the terminal 20 that the signal has been received to STA1 of the terminal 20 (step S62).

[0098] When the link management unit 220 of the terminal 20 receives a Data ACK for transmitting the data frame including “PM = 0”, the link management unit 220 of the terminal 20 transitions STA1 from the intermittent operation mode (Awake state) to the active mode, and STA2 and STA3 from the operation suspension mode (Doze state) to the active mode (step S53). As a result, each of STA1, STA2, and STA3 constituting the multi-link becomes in a state capable of receiving a wireless signal from the base station 10.

[0099] After transmitting a Data ACK for receiving “PM = 0”, the access point AP transmits a beacon signal to STA1 (anchor link) of the terminal 20 (step S54). This beacon signal includes various information elements necessary for communication.

[0100] As described above, the base station 10 in the wireless system 1 according to the embodiment can transition the STA function set to the intermittent operation mode or the operation suspension mode within the multi-link to the active mode, and can set a plurality of STA functions constituting the multi-link to a communicable state. In the above description, the case where the multi-link power save ends based on the beacon signal of the base station 10 has been exemplified, but the present invention is not limited to this. For example, the link management unit 220 of the terminal 20 may notify the link management unit 120 of the base station 10 of the end of the multi-link power save based on a user operation or application control.

[0101] (Specific Example of Operation during Multi-Link Power Save) FIGS. 20 and 21 show an example of the operation flow during multi-link power save in the wireless system 1 according to the embodiment. FIG. 20 corresponds to the operation when the access point AP receives the data of TID #2. FIG. 21 corresponds to the operation when the access point AP receives the data of TID #3. The TIDs assigned to each link in this example are the same as the link management information 121 described with reference to FIG. 14.

[0102] First, with reference to FIG. 20, the operation when the access point AP receives the data of TID #2 assigned to STA1 (anchor link) during multi-link power save will be described. As shown in FIG. 21, when the access point AP receives the data of TID #2 from the network NW, for example, the data is accumulated in the transmission queue 125 of the link management unit 120. Then, the access point AP transmits a beacon signal including a PVB indicating that the buffer status of the data of TID #2 is "1" to STA1 (step S70).

[0103] Then, the beacon signal received by STA1 of the terminal 20 is transferred to the link management unit 220. Then, the link management unit 220 checks the presence or absence of buffer data for each TID with reference to the beacon signal. Here, the link management unit 220 checks that the data of TID#2 is buffered and that STA1 associated with the data of TID#2 is in the Awake state. Based on this check result, the link management unit 220 transmits a PS-Poll (Power Save-Poll) frame requesting data transmission to the access point AP via STA1 (step S71).

[0104] When the access point AP receives a PS-Poll frame from STA1 of the terminal 20, it transmits a Data ACK including the data of TID#2 to STA1 of the terminal 20 (step S72). Thereby, STA1 of the terminal 20 can receive the data destined for itself accumulated in the access point AP.

[0105] When the transmission of the data of TID#2 is completed and the accumulation of the data of TID#2 in the transmission queue 125 is cleared, the access point AP transmits a beacon signal including a PVB indicating that the buffer status of the data of TID#2 is "0" to STA1 of the terminal 20 (step S73). That is, the access point AP notifies the link management unit 220 of the terminal 20 via STA1 that the transmission of the data of TID#2 has been completed.

[0106] Next, with reference to FIG. 21, the operation when the access point AP receives the data of TID#3 assigned to STA2 during multi-link power save will be described. As shown in FIG. 21, when the access point AP receives the data of TID#3 from the network NW, for example, the data is accumulated in the transmission queue 125 of the link management unit 120. Then, the access point AP transmits a beacon signal including a PVB indicating that the buffer status of the data of TID#3 is "1" to STA1 (step S80).

[0107] Then, the beacon signal received by STA1 of the terminal 20 is transferred to the link management unit 220. Then, the link management unit 220 refers to the beacon signal and checks the presence or absence of buffer data for each TID. Here, the link management unit 220 confirms that the data of TID#3 is buffered and that the STA2 associated with the data of TID#3 is in the Doze state. Based on this confirmation result, the link management unit 220 wakes up STA2, that is, transitions it from the Doze state to the Awake state (step S81).

[0108] After that, the link management unit 220 transmits a PS-Poll (Power Save-Poll) frame requesting the transmission of the data of TID#3 to the access point AP via STA2 (step S82). When the access point AP receives the PS-Poll frame from STA2 of the terminal 20, it transmits a Data ACK including the data of TID#3 to STA2 of the terminal 20 (step S83). Thereby, STA2 of the terminal 20 can receive the data destined for itself accumulated in the access point AP.

[0109] When the transmission of the data of TID#3 is completed and the accumulation of the data of TID#3 in the transmission queue 125 is cleared, the access point AP transmits a beacon signal including a PVB indicating that the buffer status of the data of TID#3 is "0" to STA1 of the terminal 20 (step S84). That is, the access point AP notifies the link management unit 220 of the terminal 20 via STA1 that the transmission of the data of TID#3 has been completed. This beacon signal may be received by STA2.

[0110] Then, based on the received beacon signal, the link management unit 220 causes STA2 to transition from the Awake state to the Doze state (step S85). That is, during multi-link power save, among the plurality of links constituting the multi-link, links other than the anchor link are reset to the Doze state based on the completion of data transmission.

[0111] As described above, the base station 10 in the wireless system 1 according to the embodiment can transmit data to the terminal 20 that uses multi-link power save. Note that in the above description, the case where the base station 10 receives data of the TID assigned to STA2 during multi-link power save has been described, but it is not limited thereto. Similar to STA2, STA3 can also wake up from the Doze state and receive data.

[0112] Also, although the case where data is transmitted for each STA function has been exemplified, data may be transmitted in parallel to each of the plurality of STA functions constituting the multi-link. For example, when the buffer status of each of STA1 and STA2 is "1", the link management unit 220 of the terminal 20 may instruct each of STA1 and STA2 to transmit a PS-Poll frame to the access point AP. When a plurality of links in the Doze state are associated with a TID, the link management unit 220 of the terminal 20 can wake up the plurality of links. That is, the link management unit 220 of the terminal 20 can wake up the links in the Doze state according to the buffer status of the data regardless of the number of links constituting the multi-link and receive the data.

[0113] When there are a plurality of links with the TID in the Doze state, the access point AP can also wake up some of the links. For this purpose, in addition to the AID and TID, the access point AP designates the links to be woken up and notifies the buffer information of the data. FIG. 22 shows an example of a beacon signal transmitted from the access point AP in this example. As shown in FIG. 22, in the PVB of the TID associated with a plurality of links, the presence or absence of buffer data may be notified for each link associated with the TID. For example, the PVB of TID#1 may include the PVB of link#1 associated with TID#1 and the PVB of link#2 associated with TID#1.

[0114] <3>Effects of the Embodiment According to the wireless system 1 according to the embodiment described above, the power consumption of the terminal 20 during multi-link can be suppressed. Hereinafter, the details of the effects of the wireless system 1 according to the embodiment will be described.

[0115] Base stations and terminals using a wireless LAN may be provided with a plurality of STA functions provided for each band used, such as 2.4 GHz, 5 GHz, and 6 GHz. In such a wireless system, for example, a wireless connection is established by selecting one of the plurality of STA functions, and data communication between the base station and the terminal is performed. At this time, in the wireless system, even if there is a base station corresponding to the band of the unselected STA function, the unselected STA function is not used.

[0116] In contrast, the wireless system 1 according to the embodiment establishes a multi-link between the base station 10 and the terminal 20 by utilizing a plurality of STA functions provided in each of the base station 10 and the terminal 20. Data communication by the multi-link can use a plurality of bands and can fully utilize the functions of the wireless LAN device. As a result, the wireless system 1 according to the embodiment can achieve efficient communication and improve the communication speed. On the other hand, the power consumption of the multi-link is higher than that of the single link because a plurality of STA functions are used in each of the base station 10 and the terminal 20.

[0117] Therefore, when the traffic is light or the like, the wireless system 1 according to the embodiment sets the multi-link to multi-link power save. In the multi-link power save, for example, among a plurality of STA functions constituting the multi-link, at least one STA function is set to the normal state (Awake state), and the other STA functions are set to the power saving state (Doze state). The STA function in the Awake state can receive, for example, the beacon signal of the base station 10. Also, the STA function in the Doze state is stopped in the same manner as the Disable state, for example. For this reason, the power consumption of the STA function in the Doze state is lower than that of the STA function in the Awake state.

[0118] Then, in the multi-link power save, the STA function in the Awake state receives a beacon signal including information corresponding to a plurality of STA functions constituting the multi-link. For example, when data for the STA function in the Doze state is input from the network NW to the base station 10, the base station 10 notifies the terminal 20 via the STA function (link) in the Awake state that the data is accumulated. Then, the STA function of the terminal 20 transfers the notification to the link management unit 220, and the link management unit 220 wakes up the STA function in the Doze state. As a result, the awakened STA function can obtain data from the base station 10 by transmitting a PS-Poll frame.

[0119] As described above, the wireless system 1 according to the embodiment can suppress the power consumption of the terminal 20 by utilizing multi-link power saving. Then, the link management unit 220 of the terminal 20 can appropriately wake up the Doze state STA function based on the beacon signal received by the Awake state STA function during multi-link power saving. Thereby, data communication between the base station 10 and the terminal 20 can be realized even during multi-link power saving. As a result, the wireless system 1 according to the embodiment can suppress the delay of latency during multi-link power saving.

[0120] <4>Others In the above embodiment, each STA function may notify the corresponding link management unit when the link cannot be maintained due to the movement of the terminal 20 or the like. Further, the link management unit 220 of the terminal 20 may change the multi-link state with the link management unit 120 of the base station 10 based on the notification from the STA function. Specifically, for example, the link management unit 220 of the terminal 20 and the link management unit 120 of the base station 10 may appropriately change the STA function used in the multi-link. When the multi-link state is changed, the link management units 120 and 220 update the link management information 121 and 221, respectively. Further, the link management units 120 and 220 may update the association between the traffic and the STA function according to the increase or decrease in the number of links.

[0121] The configuration of the wireless system 1 according to the embodiment is merely an example, and other configurations may be used. For example, although the case where each of the base station 10 and the terminal 20 includes three STA functions (radio signal processing units) has been illustrated, the present invention is not limited thereto. The base station 10 only needs to include at least two radio signal processing units. Similarly, the terminal 20 only needs to include at least two radio signal processing units. Also, the number of channels that each STA function can process can be appropriately set according to the frequency band used. Each of the wireless communication modules 14 and 24 may support wireless communication in a plurality of frequency bands by a plurality of communication modules, or may support wireless communication in a plurality of frequency bands by one communication module.

[0122] Also, the functional configurations of the base station 10 and the terminal 20 in the wireless system 1 according to the embodiment are merely examples. The functional configurations of the base station 10 and the terminal 20 may have other names and groupings as long as they can execute the operations described in each embodiment. For example, in the base station 10, the data processing unit 110 and the link management unit 120 may be collectively referred to as a data processing unit. Similarly, in the terminal 20, the data processing unit 210 and the link management unit 220 may be collectively referred to as a data processing unit.

[0123] Also, in the wireless system 1 according to the embodiment, the CPUs included in each of the base station 10 and the terminal 20 may be other circuits. For example, instead of the CPU, an MPU (Micro Processing Unit) or the like may be used. Also, each of the processes described in each embodiment may be realized by dedicated hardware. The wireless system 1 according to each embodiment may have a mixture of processes executed by software and processes executed by hardware, or may have only one of them.

[0124] In each embodiment, the flowchart used to explain the operations is merely an example. Each operation described in the embodiment may be rearranged within the possible range of the processing order, or other processing may be added. Also, the format of the wireless frame described in the above embodiment is merely an example. The wireless system 1 may use other wireless frame formats as long as it can execute the operations described in each embodiment.

[0125] Note that the present invention is not limited to the above embodiments, and various modifications can be made without departing from the gist thereof at the implementation stage. Also, the embodiments may be combined as appropriate, and in that case, the combined effects can be obtained. Furthermore, the above embodiments include various inventions, and various inventions can be extracted by combinations selected from the plurality of disclosed constituent elements. For example, even if some constituent elements are deleted from all the constituent elements shown in the embodiment, if the problem can be solved and the effect can be obtained, the configuration from which these constituent elements are deleted can be extracted as an invention.

Description of Reference Numerals

[0126] 1... Wireless system 10... Base station 20... Terminal 30... Server 11, 21... CPU 12, 22... ROM 13, 23... RAM 14, 24... Wireless communication module 15... Wired communication module 25... Display 26... Storage 110, 210... Data processing unit 120, 220... Link management unit 121, 221... Link management information 122, 222... Association processing unit 123, 223... Authentication processing unit 124... Data categorization unit 125... Transmission queue 126…CSMA / CA Execution Unit 127…Data Collision Management Unit 130, 140, 150, 230, 240, 250…Wireless Signal Processing Unit

Claims

1. A base station that communicates with a terminal, a first radio signal processing unit that establishes a first link with the terminal; a second radio signal processing unit that establishes a second link different from the first link with the terminal; data transmitted using a multilink formed by the first link and the second link is associated with at least one of the first link or the second link based on TID information of the data; When the terminal is in a state where it is unable to receive the data through the link with which the data is associated, the data is stored, and for each TID, a beacon signal including information indicating whether or not each link associated with the TID is a predetermined link from which the data should be acquired is transmitted to the terminal using at least one of the first link and the second link; The radio signal processing unit that operates on the predetermined link, either the first radio signal processing unit or the second radio signal processing unit, transmits the data. Base station.

2. The beacon signal includes information indicating whether or not data assigned to the first link among the data has been accumulated, and information indicating whether or not data assigned to the second link among the data has been accumulated. The base station of claim 1 .

3. A terminal that communicates with a base station, a first radio signal processing unit that establishes a first link with the base station; a second radio signal processing unit that establishes a second link different from the first link with the base station, data transmitted using a multilink formed by the first link and the second link is associated with at least one of the first link or the second link based on TID information of the data; When the data cannot be received on the link associated with the data, the data is stored by a base station, and a beacon signal including information indicating whether or not each link associated with the TID is a predetermined link from which the data should be acquired is received by the terminal using at least one of the first link or the second link, for each TID; The radio signal processing unit operating on the predetermined link, either the first radio signal processing unit or the second radio signal processing unit, acquires the data. Terminal.

4. The beacon signal includes information indicating whether or not data assigned to the first link among the data has been accumulated, and information indicating whether or not data assigned to the second link among the data has been accumulated. The terminal according to claim 3.

5. A base station that communicates with a terminal, a first radio signal processing unit that establishes a first link with the terminal; a second radio signal processing unit that establishes a second link different from the first link with the terminal; data transmitted using a multilink formed by the first link and the second link is associated with at least one of the first link or the second link based on TID information of the data; When the terminal is in a state where it is unable to receive the data through the link with which the data is associated, storing the data and transmitting a beacon signal to the terminal using a predetermined link from which the data should be acquired, of at least one of the first link and the second link; a radio signal processing unit operating on the predetermined link out of the first radio signal processing unit or the second radio signal processing unit transmits the data; a PVB, which is a buffer associated with the TID information; The PVB includes a link-specific PVB, which is a buffer for each link associated with the first link and the second link. Base station.

6. A terminal that communicates with a base station, a first radio signal processing unit that establishes a first link with the base station; a second radio signal processing unit that establishes a second link different from the first link with the base station, data transmitted using a multilink formed by the first link and the second link is associated with at least one of the first link or the second link based on TID information of the data; When the data cannot be received on a link associated with the data, the data is stored by a base station, and a beacon signal is received by the terminal using a predetermined link from which the data should be acquired, which is at least one of the first link and the second link; a radio signal processing unit operating on the predetermined link out of the first radio signal processing unit or the second radio signal processing unit acquires the data; a PVB, which is a buffer associated with the TID information; The PVB includes a link-specific PVB, which is a buffer for each link associated with the first link and the second link. Terminal.

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