Wireless communication apparatus and method

Abstract

The present technology relates to a wireless communication device and method that enable efficient communication. The wireless communication apparatus controls a second network including a plurality of first networks, each first network including an access point and one or more wireless communication terminals, and has: a control unit that generates control information for controlling communication of another first network on the basis of communication information relating to communication of a predetermined first network; and a communication unit that transmits a frame including the control information and an identifier indicating that the frame is transmitted from a second network controlled by the wireless communication apparatus. This technique is suitable for controlling base stations, base stations, slave units, and the like.

Description

[0001] This application is a divisional application of the invention patent application with the application date of February 13, 2019, the application number of 201980014483.1, and the invention title of "Wireless Communication Device and Method". Technical Field

[0002] The present technology relates to wireless communication devices and methods, and more particularly, to wireless communication devices and methods capable of more efficient communication. Background Art

[0003] In a wireless LAN (local area network), not only the frequency resources in the 2.4 GHz / 5 GHz bands used in the related art but also the frequency resources in higher frequency bands (that is, bands of 6 GHz or 60 GHz) have become available.

[0004] Generally, the characteristics of a low frequency band are, on the one hand, a wide coverage range (communicable range), and on the other hand, a narrow bandwidth that can be provided. The narrow bandwidth that can be provided results in a small amount of information that can be transmitted, that is, a small communication capacity. In contrast, the characteristics of a high frequency band are, on the one hand, a wide frequency band that can be provided, and on the other hand, a narrow coverage range.

[0005] Therefore, it is considered to provide communication capacity and coverage by using a large number of small networks including the use of high frequency bands and a network of control base stations that integrate and control the networks in communication in the low frequency band.

[0006] In addition, as a technology mainly used for cellular systems, there has been proposed a technology in which a control base station connected to a plurality of base stations and wireless terminals collects radio frequency information related to communication between each base station and each wireless terminal to determine the operating frequency of each wireless terminal, and notifies the operating frequency to each wireless terminal using a control signal (see, for example, PTL 1).

[0007] Citation List

[0008] Patent Literature

[0009] [PTL 1]

[0010] Japanese Patent Laid-Open No. 2016-116086 Summary of the Invention

[0011] Technical Problem

[0012] However, the above technology cannot perform more efficient communication.

[0013] For example, a known radio LAN does not adopt a network configuration including a plurality of small networks, and in particular, a known base station cannot perform the operation of such a control base station: the control base station is connected to a plurality of base stations but does not itself perform data transmission.

[0014] In addition, the technology described in PTL 1 mainly uses a cellular system and cannot be directly applied to a wireless LAN.

[0015] That is, in a system where a given control base station exists in a wireless LAN, there is a space reuse technology for performing interference control to allow multiple communications using the same frequency. Therefore, the direct use of the method described in PTL 1 results in insufficient information for achieving optimal space reuse, excluding efficient communication that effectively uses resources.

[0016] In view of this situation, an object of the present technology is to enable more efficient communication.

[0017] Solution to the problem

[0018] A wireless communication device according to a first aspect of the present technology is a wireless communication device that controls a second network including a plurality of first networks, each first network including an access point and one or more wireless communication terminals. The wireless communication device includes: a control section configured to generate control information for controlling communication in another first network based on communication information related to communication in a predetermined first network; and a communication section configured to transmit a frame that includes the control information and an identifier indicating that the frame has been transmitted from the second network controlled by the wireless communication device.

[0019] A wireless communication method according to a first aspect of the present technology is a wireless communication method corresponding to the wireless communication device according to the first aspect of the present technology.

[0020] In a first aspect of the present technology, in a wireless communication device that controls a second network including the plurality of first networks, each first network includes an access point and the one or more wireless communication terminals, and based on communication information related to communication in a predetermined first network, control information for controlling communication in another first network is generated, and a frame is transmitted that includes the control information and an identifier indicating that the frame has been transmitted from the second network controlled by the wireless communication device.

[0021] A wireless communication device according to a second aspect of the present technology is a wireless communication device belonging to a first network including an access point and one or more wireless communication terminals. The wireless communication device includes: a control section configured to control the transmission of a frame including communication information related to communication in the first network to which the wireless communication device belongs to a master access point that controls a second network including a plurality of first networks, or to control communication in the first network based on control information included in a frame received from the master access point, the control information being generated based on communication information in another first network different from the first network to which the wireless communication device belongs.

[0022] The wireless communication method according to the second aspect of the present technology is a wireless communication method corresponding to a wireless communication device according to the second aspect of the present technology.

[0023] In the second aspect of the present technology, in a wireless communication device belonging to a first network including an access point and the one or more wireless communication terminals, transmission of a frame including communication information related to communication in the first network to which the wireless communication device belongs is controlled, the main access point controls a second network including the plurality of first networks, or communication in the first network is controlled based on control information included in a frame received from the main access point, and the control information is generated based on communication information in another first network different from the first network to which the wireless communication device belongs.

[0024] Advantageous effects of the invention

[0025] According to the first and second aspects of the present technology, more efficient communication can be performed.

[0026] It should be noted that the effects described here are not necessarily restrictive, and any effects described in the present disclosure may be provided. Brief description of the drawings

[0027] Figure 1 It is a diagram showing a structural example of a wireless communication system.

[0028] Figure 2 It is a diagram showing a structural example of a wireless communication device.

[0029] Figure 3 It is a diagram showing the structure of a phantom BSS.

[0030] Figure 4 It is a diagram showing the structure of a phantom BSS.

[0031] Figure 5 It is a diagram showing communication control of a control base station.

[0032] Figure 6 It is a diagram showing communication control of a control base station.

[0033] Figure 7 It is a diagram showing an example of a frame format used in communication in a phantom BSS.

[0034] Figure 8 It is a flowchart showing a phantom BSS construction process.

[0035] Figure 9 It is a flowchart showing a connection process.

[0036] Figure 10 It is a flowchart showing a BSS communication control process.

[0037] Figure 11 This is a flowchart showing the BSS communication processing on the SR information sending side.

[0038] Figure 12 This is a flowchart showing the BSS communication processing on the control information receiving side.

[0039] Figure 13 This is a flowchart showing the BSS communication control processing.

[0040] Figure 14 This is a diagram showing an example of the structure of a computer. Detailed implementation manners

[0041] Embodiments applying the present technology will be described below with reference to the accompanying drawings.

[0042] <First Embodiment>

[0043] <Example of the structure of a wireless communication system>

[0044] In the present technology, in order to establish a network including a large number of small networks using a high frequency band and a control base station that integrates and controls the networks through communication in a low frequency band, frame switching is performed to establish a connection between the control base station and each base station or slave terminal. This eliminates the need for pre-design of the network and allows each device to autonomously construct the network.

[0045] In addition, in the present technology, the control base station notifies control information to each base station and slave terminal using frames and communication methods, and the control base station notifies the information required for space recycling to each base station and slave terminal. This enables more efficient communication using space recycling.

[0046] In addition, in the present technology, the control base station adds an identifier of the control base station to the signal transmitted by the control base station before transmitting the signal. This enables the control base station, the base station, and the slave terminal to stop receiving signals that are not required by the control base station, the base station, and the slave terminal from another control base station, allowing effective utilization of communication resources and suppression of uneconomical power consumption.

[0047] Now, more specific embodiments of the present technology will be described.

[0048] For example, as Figure 1 shown, a wireless communication system applying the present technology is constructed.

[0049] Figure 1 The wireless communication system shown in

[0050] For example, a low-level network is a network called a BSS (Basic Service Set). The BSS includes a base station called an access point (AP) and one or more slave terminals corresponding to wireless communication terminals connected to the base station and called stations.

[0051] In Figure 1 the example shown in, one BSS (hereinafter referred to as BSS1) includes the base station AP1 and the slave terminals STA1a and STA1b connected to the base station AP1. It should be noted that when the slave terminals STA1a and STA1b do not need to be particularly distinguished from each other, the slave terminals STA1a and STA1b are also simply referred to as the slave terminal STA1.

[0052] In addition, one BSS (hereinafter referred to as BSS2) includes the base station AP2 and the slave terminals STA2a and STA2b connected to the base station AP2. It should be noted that when the slave terminals STA2a and STA2b do not need to be particularly distinguished from each other, the slave terminals STA2a and STA2b are also simply referred to as the slave terminal STA2.

[0053] In addition, in Figure 1 the example shown in, BSS1 and BSS2 are managed by a control base station MAP1 serving as a master access point (master AP), and the control base station MAP1, BSS1, and BSS2 form the high-level network.

[0054] The high-level network is hereinafter referred to as a phantom BSS, and in particular, the high-level network including the control base station MAP1, BSS1, and BSS2 is also referred to as phantom BSS1. For example, phantom BSS1 is a wireless network in which the base station AP1 and the base station AP2 are not connected by wire or the like, and the control base station MAP1 controls phantom BSS1.

[0055] In BSS1 and BSS2, as indicated by the dashed arrows in the drawings, a first frequency band is used to implement communication. In contrast, as indicated by the solid arrows in the drawings, the control base station MAP1 is connected to the base station AP1, the slave terminal STA1a, the slave terminal STA1b, the base station AP2, the slave terminal STA2a, and the slave terminal STA2b via a second frequency band. For example, the first frequency band is higher than the second frequency band. In addition, communication in the second frequency band can be implemented using a transmission power different from the transmission power used for communication in the first frequency band. For example, communication in the second frequency band can be implemented using a transmission power higher than the transmission power used to perform communication in the first frequency band. In addition, communication in the second frequency band can be implemented using a frequency bandwidth different from the frequency bandwidth used for communication in the first frequency band. For example, communication in the second frequency band can be implemented using a frequency bandwidth narrower than the frequency bandwidth used for communication in the first frequency band.

[0056] Note that the control base station MAP1 can be used as a base station for managing (controlling) the BSS, or, unlike the example in Figure 1 , does not need to include any slave terminals controlled by the base station MAP1 or form a BSS.

[0057] <Structural Example of Wireless Communication Device>

[0058] Now, a specific structural example of a wireless communication device corresponding to the above control base station MAP1, base station AP1, base station AP2, slave terminal STA1, or slave terminal STA2.

[0059] Figure 2 is a diagram showing a structural example of a wireless communication device to which the present technology is applied.

[0060] Figure 2 The wireless communication device 11 shown in Figure 1 can be used as any one of the control base station MAP1, base station AP1, base station AP2, slave terminal STA1, and slave terminal STA2 shown in

[0061] The wireless communication device 11 includes a data processing section 21, a control section 22, a communication section 23, antennas 24-1 to 24-N, and a power supply section 25. Hereinafter, when it is not necessary to distinguish between antennas 24-1 to 24-N from each other, antennas 24-1 to 24-N are also simply referred to as antenna 24.

[0062] In addition, the communication section 23 includes a modulation and demodulation section 31, a signal processing section 32, a channel estimation section 33, wireless interface sections 34-1 to wireless interface sections 34-N, and amplifier sections 35-1 to amplifier sections 35-N.

[0063] Hereinafter, when it is not necessary to distinguish between wireless interface sections 34-1 to 34-N from each other, wireless interface sections 34-1 to 34-N are also simply referred to as wireless interface section 34. In addition, when it is not necessary to distinguish between amplifier sections 35-1 to 35-N from each other, amplifier sections 35-1 to 35-N are also simply referred to as amplifier section 35.

[0064] Note that in the example shown in Figure 2 , N (2 ≤ N) wireless interface sections 34, N amplifier sections 35, and N antennas 24 are provided, but a single wireless interface section 34, a single amplifier section 35, and a single antenna 24 can be provided, or two or more of any number of wireless interface sections 34, two or more of any number of amplifier sections 35, and two or more of any number of antennas 24 can be provided.

[0065] In addition, the radio interface section 34, the amplifier section 35, and the antenna 24 can be formed as one component (the radio interface section 34, the amplifier section 35, and the antenna 24 can be configured as one processing section). In addition, the function of the amplifier section 35 can be included in the radio interface section 34, and the amplifier section 35 is omitted.

[0066] When the data processing section 21 transmits data input from a higher layer of the protocol (that is, transmits a packet (frame)), the data processing section 21 generates a packet for wireless transmission from the data input from the higher layer of the protocol, and performs data processing (such as adding a header for performing media access control (MAC) and adding an error detection code). The data processing section 21 provides the packet obtained through data processing to the modulation and demodulation section 31.

[0067] In addition, the data processing section 21 receives data from the modulation and demodulation section 31, that is, receives a packet. The data processing section 21 performs data processing on the packet provided by the modulation and demodulation section 31, such as analysis of the MAC header, detection of packet errors, and reordering processing. The data processing section 21 provides the data obtained through data processing to the higher layer of the protocol.

[0068] The control section 22 transfers information between the respective sections (the data processing section 21, the control section 22, and the communication section 23 (the modulation and demodulation section 31, the signal processing section 32, the channel estimation section 33, the radio interface section 34, and the amplifier section 35)).

[0069] In addition, the control section 22 performs control of the respective sections of the wireless communication device 11, such as setting parameters in the modulation and demodulation section 31 and the signal processing section 32, scheduling of packets in the data processing section 21, setting of parameters in the radio interface section 34 and the amplifier section 35, and control of the transmission power.

[0070] In addition, the control section 22 appropriately controls the respective sections of the wireless communication device 11 to implement the construction of the above-mentioned phantom BSS1, transmission and reception of signals (frames) in the phantom BSS1, operation of the phantom BSS1, and the like.

[0071] The communication section 23 performs processing required for transmitting or receiving a packet through wireless communication, and transmits or receives a packet via the antenna 24.

[0072] The antenna 24 transmits the packet (frame) provided by the communication section 23 as a wireless signal. In addition, the antenna 24 receives the wireless signal in the packet and provides it to the communication section 23.

[0073] In the case of transmitting a packet, the modulation and demodulation section 31 performs conversion processing (such as encoding (decoding), interleaving, and modulation) on the packet provided from the data processing section 21 based on the encoding and modulation scheme with parameters set by the control section 22 to generate a data symbol stream. The modulation and demodulation section 31 provides the generated data symbol stream to the signal processing section 32.

[0074] On the other hand, in the case of receiving a packet, the modulation and demodulation section 31 performs processing opposite (reverse) to the processing performed in the case of transmitting a packet as described above on the data symbol stream provided from the signal processing section 32. In other words, the modulation and demodulation section 31 performs reverse processing (such as demodulation, deinterleaving, or decoding) on the data symbol stream provided from the signal processing section 32 and provides the packet obtained through the reverse processing to the data processing section 21 and the control section 22.

[0075] In the case of transmitting a packet, the signal processing section 32 performs signal processing on the data symbol stream from the modulation and demodulation section 31 as needed, and the signal processing includes spatial processing such as MIMO (multiple input multiple output) that contributes to spatial separation. Therefore, the signal processing section 32 generates one or more transmission symbol streams. The signal processing section 32 provides each of the generated one or more transmission symbol streams to each of the one or more radio interface sections 34.

[0076] On the other hand, in the case of receiving a packet, the signal processing section 32 performs signal processing on the received symbol stream provided from the radio interface section 34 and performs spatial processing (such as spatial separation) on the received symbol stream as needed, and provides the obtained data symbol stream to the modulation and demodulation section 31.

[0077] The channel estimation section 33 calculates the complex channel gain of the propagation path based on the preamble part and the training signal part of the received symbol stream provided from the radio interface section 34. The channel estimation section 33 provides the calculated complex channel gain to the modulation and demodulation section 31 and the signal processing section 32 via the control section 22. The obtained complex channel gain is used for demodulation in the modulation and demodulation section 31 and spatial processing in the signal processing section 32.

[0078] In the case of transmitting a packet, the radio interface section 34 performs DA (digital - to - analog) conversion on the transmission symbol stream corresponding to the input from the signal processing section 32 and converts it into an analog signal, and performs processing (such as filtering and up - conversion to the carrier frequency). The radio interface section 34 provides the transmission signal obtained through processing (such as DA conversion, filtering, and up - conversion to the carrier frequency) to the amplifier section 35.

[0079] On the other hand, in the case of receiving a packet, the wireless interface section 34 performs processing opposite to the processing performed in the case of transmitting a packet on the input (received signal) from the amplifier section 35, and provides the signal (received symbol stream) obtained through the opposite processing to the signal processing section 32 and the channel estimation section 33.

[0080] In the case of transmitting a packet, the amplifier section 35 amplifies the transmission signal from the wireless interface section 34 to a predetermined power, and the wireless communication device 11 wirelessly transmits the amplified transmission signal as a wireless signal from the antenna 24.

[0081] In addition, in the case of receiving a packet, the amplifier section 35 amplifies the wireless signal received by the antenna 24 to a predetermined power, and provides the amplified signal to the wireless interface section 34 as a received signal.

[0082] It should be noted that, for the amplifier section 35, at least one of the functions used during transmission or the functions used during reception can be included in the wireless interface section 34.

[0083] The power supply section 25 includes a battery power supply or a fixed power supply, and supplies power to each part of the wireless communication device 11.

[0084] <Configuration of Phantom BSS>

[0085] Now, the configuration of the above-mentioned phantom BSS, the control of communication in the phantom BSS, and the frame format of communication in the phantom BSS will be described.

[0086] First, the configuration of the phantom BSS will be described.

[0087] The phantom BSS includes one or more base stations or a plurality of BSSs formed (configured) by base stations. In the sequence for the configuration of the phantom BSS, for example, as Figure 3 shown, the control base station (master AP), the base station (AP), and the slave terminals (STAs) connected to the base station perform respective operations to configure the phantom BSS.

[0088] In Figure 3 the example shown, the character "master AP" represents the control base station, the character "AP" represents the base station, and the character "STA" represents the slave terminal. For example, the control base station corresponds to Figure 1 the control base station MAP1 in Figure 1 the base station corresponds to the base station AP1 or base station AP2 in

[0089] Note that the control base station does not need to include any subordinate terminals directly controlled by the control base station, or does not need to be configured as a BSS of the base station by the control base station, or the BSS of the control base station can be configured. Additionally, the subordinate terminal can be a station not connected to any base station, in other words, an unassociated STA.

[0090] In Figure 3 the example shown, first, the control base station transmits a primary beacon frame corresponding to a beacon frame used as a phantom BSS, as indicated by arrow A11. At this time, for example, the control base station transmits the primary beacon frame at a frequency lower than the transmission frequency of the beacon frame from the normal BSS transmitted by the base station within the detectable range.

[0091] The primary beacon frame stores an identifier for identifying the control base station, an identifier for identifying the phantom BSS managed (controlled) by the control base station, and operation and function information including information related to the operation and function of the phantom BSS.

[0092] Here, the identifier for identifying the phantom BSS is an identifier that indicates that the frame including this identifier has been transmitted through communication in the phantom BSS, that is, indicates that the frame has been transmitted from the phantom BSS controlled by the control base station. Additionally, the function of the phantom BSS is a function that can be supported by the phantom BSS, such as the support of the phantom BSS for space recycling.

[0093] The primary beacon frame includes destination information indicating the destination of the primary beacon frame, and the destination indicated by the destination information can correspond to the broadcast address, in other words, all wireless communication devices on the network.

[0094] When the primary beacon frame is transmitted by the control base station in this way, the base stations and subordinate terminals within the range where the control base station can communicate with the base stations and subordinate terminals receive the transmitted primary beacon frame.

[0095] Then, the base stations and subordinate terminals determine whether to perform the construction of the phantom BSS controlled (managed) by the control base station and the connection to the phantom BSS based on the information stored in the received primary beacon frame (that is, the identifier of the control base station, the identifier of the phantom BSS, and the operation and function information).

[0096] Here, the state of constructing the phantom BSS is the state where the base station or subordinate terminal receives a frame including the identifier of the phantom BSS, and from the perspective of the control base station, it is the state where the control base station identifies which base station or subordinate terminal is under the control of the control base station.

[0097] Additionally, the state of connection to the phantom BSS (control base station) is the state of association between the control base station and the base station or subordinate terminal.

[0098] A base station or a slave terminal that has determined not to perform the construction of a phantom BSS and the connection to the phantom BSS after receiving the master beacon frame does not subsequently transmit anything special.

[0099] In contrast, a base station or a slave terminal that has determined to perform the construction of a phantom BSS and the connection to the phantom BSS performs a series of frame exchanges described below.

[0100] In Figure 3 the arrows A12 and A13 indicate the frame exchange between the control base station and the base station, and the arrows A14 and A15 indicate the frame exchange between the control base station and the slave terminal.

[0101] In the series of frame exchanges for the construction of a phantom BSS and the connection to the phantom BSS, first, the base station or the slave terminal sends a master probe request frame to the control base station to notify the control base station of the presence of the base station or the slave terminal.

[0102] The master probe request frame is, for example, a frame including an identifier identifying the base station or the slave terminal corresponding to the source of the master probe request frame and an identifier of the phantom BSS, and this frame is destined for the control base station.

[0103] When receiving the master probe request frame sent by the base station or the slave terminal, the control base station sends a master probe response frame to the base station or the slave terminal as a response to the master probe request frame to notify the base station or the slave terminal corresponding to the source of the master probe request frame that the presence of the base station or the slave terminal has been confirmed.

[0104] Then, the base station or the slave terminal sends a master verification request frame corresponding to the frame indicating the request for verification to the control base station to request the control base station to verify the base station or the slave terminal.

[0105] When receiving the master verification request frame, the control base station verifies the base station or the slave terminal. As a result, in the case where the base station or the slave terminal is correctly verified, the control base station sends a master verification response frame to the base station or the slave terminal to notify the base station or the slave terminal that the base station or the slave terminal has been verified.

[0106] In addition, when receiving the master verification response frame, the base station or the slave terminal sends a master association request frame corresponding to the frame indicating the request for connection to the control base station to request connection to the control base station from the control base station.

[0107] Then, when receiving the master association request frame, the control base station sends a master association response frame indicating that the base station or the slave terminal is allowed to connect to the control base station to notify the base station or the slave terminal that the connection is allowed. The series of frame exchanges ends.

[0108] When the frame exchange is performed as described above, the phantom BSS is constructed and the connection to the phantom BSS is completed.

[0109] Note that the control base station can perform the above frame exchange with multiple base stations or slave terminals, and unassociated STAs can perform the above frame exchange with the control base station while remaining unconnected to the base station (BSS) to connect to the phantom BSS (control base station).

[0110] In addition, in Figure 3 the above example shown, the slave terminal directly performs frame exchange with the control base station to connect to the control base station. However, each slave terminal can be connected to the control base station via the base station.

[0111] In this case, for example, the sequence for constructing the phantom BSS is as Figure 4 shown. Note that in Figure 4 the character "master AP" represents the control base station, the character "AP" represents the base station, and the character "STA" represents the slave terminal.

[0112] In Figure 4 the example in, as indicated by the arrow A11 in Figure 3 , the control base station sends the master beacon frame of the phantom BSS, as indicated by the arrow A21.

[0113] Then, the base station receives the master beacon frame, determines to perform the construction of the phantom BSS and the connection to the phantom BSS, and then performs frame exchange with the control base station as indicated by the arrows A12 and A13 in Figure 3 , as indicated by the arrows A22 and A23.

[0114] Specifically, the control base station and the base station exchange (send and receive) the master probe request frame, master probe response frame, master authentication request frame, master authentication response frame, master association request frame, and master association response frame as described above.

[0115] Note that in this example, the slave terminal does not perform frame exchange with the control base station.

[0116] When frame exchange is performed between the control base station and the base station, the base station connected to the control base station (phantom BSS) then sends a frame (STA info) including STA information corresponding to the information related to the connection between the slave terminal controlled by the base station and the control base station, as indicated by the arrow A24. The frame including STA information is specifically referred to as the STA info frame. The STA info frame is a frame for establishing the connection between the control base station and the slave terminal controlled by the base station.

[0117] The STA information stored in the STA info frame includes, for example, type information about the slave terminal for each slave terminal controlled by the base station, an identifier for identifying the slave terminal, function information indicating the function of the slave terminal, and position-related information related to the relative or absolute position of the slave terminal in space.

[0118] Here, the type information about the slave terminal is information indicating, for example, which wireless communication standard the slave terminal supports, and the function information about the slave terminal is information indicating, for example, the functions included in the functions of the wireless communication standard supported by the slave terminal and that can be supported by the slave terminal.

[0119] The control base station that has received such an STA info frame can know the existence of the slave terminals controlled by each base station without direct frame exchange with the slave terminals, and can identify the wireless communication standards and functions that can be supported by the slave terminals, the positions of the slave terminals, etc.

[0120] It should be noted that the STA info frame can be sent spontaneously from the base station, or the base station can send the STA info frame in response to a request from the control base station.

[0121] In addition, the STA info frame can be sent by the base station as part of a primary probe request frame, a primary authentication request frame, or a primary association request frame. Specifically, the STA information can be stored in a frame that can be used as the STA info frame.

[0122] Similarly, in the case where the control base station requests the base station to send the STA info frame, the request can be included in the primary probe response frame, the primary authentication response frame, or the primary association response frame.

[0123] In addition, the control base station that has received the STA info frame can notify the base station of information related to the slave terminals allowed to be connected to the phantom BSS. Here, the slave terminals not allowed to be connected to the phantom BSS include, for example, the slave terminals that do not support the functions of the phantom BSS.

[0124] In addition, the base station that has sent the STA info frame can subsequently send a primary AP info frame including control base station information containing information related to the control base station to the slave terminals controlled by the base station, as indicated by arrow A25. The primary AP info frame is a frame for establishing a connection between the control base station and the slave terminals.

[0125] The control base station information stored in the primary AP info frame includes, for example, type information about the control base station, an identifier of the control base station, function information indicating the functions supported by the control base station, and position-related information related to the relative or absolute position of the control base station in space. Here, the type information and function information about the control base station are similar to the type information and function information about the slave terminals.

[0126] It should be noted that the primary AP info frame can be sent separately to each slave terminal, in other words, it can be addressed to each slave terminal or to multiple addresses, indicating that the frame is addressed to multiple slave terminals.

[0127] When receiving the master AP info frame as described above, each slave terminal can identify the control base station to which the base station connected to the slave terminal is connected from the control base station information stored in the master AP info frame, and thus establish a connection with the control base station based on the control base station information.

[0128] Specifically, each of the control base station and the slave terminal can identify that the slave terminal is connected to the control base station from the STA information and the control base station information, and instruct the control base station and the slave terminal to be connected via the base station. In this case, each slave terminal can directly connect to the control base station without frame exchange with the control base station.

[0129] Here, the following frames can be transmitted in a second frequency band different from the first frequency band used for BSS communication: the master beacon frame, the master probe request frame, the master probe response frame, the master authentication request frame, the master authentication response frame, the master association request frame, the master association response frame, and the STA info frame transmitted in the sequence described in Figure 3 and Figure 4 The second frequency band used for communication in the phantom BSS can be defined as a frequency band lower than the first frequency band used for BSS communication.

[0130] It should be noted that the master AP info frame sent from the base station to the slave terminal can be sent in the second frequency band used for communication in the phantom BSS or in the first frequency band used for BSS communication.

[0131] In addition, the above frames can have an identifier indicating that the frame has been sent from the phantom BSS (in other words, the identifier of the phantom BSS) for transmission; the above frames include the master beacon frame, the master probe request frame, the master probe response frame, the master authentication request frame, the master authentication response frame, the master association request frame, the master association response frame, and the STA info frame.

[0132] The identifier of the phantom BSS can be stored in (applied to) the physical header (Phy header) of each frame, for example. In addition, the same identifier of the phantom BSS can be used for multiple phantom BSSs, or different identifiers (values) can be used for each phantom BSS.

[0133] In addition, the first frequency band used for BSS communication can be used to send the master beacon frame, the master probe request frame, the master probe response frame, the master authentication request frame, the master authentication response frame, the master association request frame, the master association response frame, and the STA info frame, in other words, the first frequency band can be the same as the second frequency band.

[0134]

[0135] ​In this case, for example, the identifier of the phantom BSS can be one of a plurality of identifiers that are not actually used for the assignment of the BSS but are used as identifiers by the BSS, or can be the same as the identifier actually used by the BSS.

[0136] Specifically, for example, in Figure 1 In the example shown, multiple BSS color information with different values is assumed to be assigned to BSS1 as the identifier of BBS1. Here, for example, it is assumed that: BSS color information with a value of C1 and BSS color information with a value of C2 are assigned to BSS1, and the BSS color information with a value of C1 is used as the actual identifier of BSS1.

[0137] At this time, for example, when the control base station MAP1 communicates with the base station AP1 included in BSS1 or the slave terminal STA1, in other words, when sending a frame destined for the base station AP1 or the slave terminal STA1, the BSS color information with a value of C1 corresponding to the identifier of BSS1 to which the base station AP1 or the slave terminal STA1 belongs can be directly used as the identifier of the phantom BSS1.

[0138] In this case, the base station AP2 included in BSS2 or the slave terminal STA2 can determine that a frame including the BSS color information with a value of C1 and sent from the phantom BSS1 is not destined for the base station AP2 or the slave terminal STA2 and ends receiving the frame.

[0139] In addition, the BSS color information with a value of C2 can be directly used as the identifier of the phantom BSS1. In this case, whether the frame is sent from BSS1 or from the phantom BSS1 can be easily identified. In addition, in this case, BSS2 can be assigned the BSS color information with a value of C2 as the identifier of the phantom BSS1.

[0140] In addition, according to the transmission band, the master AP info frame can include the identifier of the BSS indicating that the frame has been sent from the BSS or the identifier of the phantom BSS indicating that the frame has been sent from the phantom BSS.

[0141] In addition, during the sequence for constructing the phantom BSS described with reference to Figure 3 or Figure 4 or before or after the sequence, the control base station can execute a check sequence for checking whether a phantom BSS has been constructed between the control base station and the base station or the slave terminal, whether signals (frames) can be sent and received from the phantom BSS between the control base station and the base station or the slave terminal, and whether the base station or the slave terminal supports the operation of the phantom BSS.

[0142] In this case, for example, the control base station sends a capability check request frame including information related to the phantom BSS (such as type information about the control base station and function information about the control base station) to the base station or from the terminal, which allows the base station or from the terminal to check whether signal transmission and reception are possible or to check the operation of communication in the phantom BSS.

[0143] When receiving the request frame sent from the control base station, the base station or from the terminal performs a check on whether signal transmission and reception can be performed, a check on the operation of communication in the phantom BSS, etc., based on the information about the phantom BSS included in the request frame, and sends a capability check response frame indicating the result of the check to the control base station.

[0144] By exchanging the request frame and response frame for capability check between the control base station and the base station or from the terminal in this way, the configuration or operation of the phantom BSS can be checked. It should be noted that this check sequence can be performed between the control base station and an unassociated STA.

[0145] In addition, the control base station can determine whether it is appropriate for the from-terminal connected to the control base station to be connected to another base station different from the base station to which the from-terminal is currently connected.

[0146] For example, based on the spatial position relationship (in other words, the distance from each base station to the from-terminal) between the from-terminal identified based on the location-related information included in the STA info frame and different base stations, the control base station determines whether it is appropriate to connect the from-terminal to another base station.

[0147] Then, when it is determined that it is appropriate to connect the from-terminal to another base station, the control base station selects an appropriate base station as the new connection destination for the from-terminal (for example, the base station closest to the from-terminal), and sends a frame including information related to the base station to the from-terminal. In other words, a frame inviting connection to another base station different from the BSS to which the from-terminal belongs is sent to the from-terminal. For example, the frame includes the identifier of the base station, etc.

[0148] Therefore, the from-terminal that has received the frame from the control base station can change the connection destination to the new base station to be connected indicated by the information included in the frame.

[0149] In addition, when detecting a connection from an unassociated STA, the control base station can select an appropriate base station to be connected to the unassociated STA, and send a frame including information related to the selected base station to the unassociated STA. In this case, the unassociated STA that has received the frame from the control base station can start connecting to the base station to be connected indicated by the information included in the frame.

[0150] <Control of Communication in Phantom BSS>

[0151] When the phantom BSS is constructed as described above, the control base station controls the communication in the phantom BSS and the BSS so that more efficient communication can be achieved.

[0152] For example, the phantom BSS includes a plurality of BSSs, and the efficient operation of the BSSs requires notifying the BSSs included in the phantom BSS of information related to the communication in each BSS. In particular, the wireless LAN requires notification of information about the assumptions of applications for spatial recycling corresponding to the technology for efficiently using resources. In addition, notifications from the control base station itself need to be prevented from interfering with the BSSs controlled by another base station.

[0153] Therefore, in the present technology, for example, according to Figure 5 the sequence shown in

[0154] it should be noted that Figure 5 represents such an example: in the phantom BSS1 shown in Figure 1 the control base station MAP1 controls the communication in BSS2.

[0155] In Figure 5 the character "master AP" represents the control base station MAP1, the character "AP1" represents the base station AP1, and the character "STA1" represents the slave terminal STA1. In addition, the character "AP2" represents the base station AP2, and the character "STA2" represents the slave terminal STA2.

[0156] First, in the BSSs included in the phantom BSS, the base station or slave terminal to communicate notifies the control base station MAP1 of information related to the communication in the BSS to which the base station or slave terminal belongs (that is, SR information (SRinfo) including communication information).

[0157] In this example, the base station AP1 sends an SRinfo frame FL11 (packet) including SR information to the control base station MAP1.

[0158] For example, the SR information includes at least one of an identifier of the base station or slave terminal to communicate, schedule information, resource information, transmission power information, modulation and coding scheme information, allowable interference intensity information, priority, buffer information, communication type information, or information related to the location and number of wireless communication terminals.

[0159] Here, the schedule information is information indicating the schedule for the communication of the BSS, such as the start time of frame transmission and the length of the frame (signal) to be transmitted.

[0160] In addition, resource information is information indicating frequency resources and spatial resources for communication in a BSS, and transmission power information is information indicating the transmission power of frames (packets) during communication in the BSS.

[0161] Modulation and coding scheme information is information indicating the modulation and coding scheme used during communication in a BSS, and allowed interference intensity information is information indicating the allowed interference intensity in the communication of the BSS determined by the transmission power information and the modulation and coding scheme information. Priority is information indicating the priority of frames (packets) transmitted and received in the communication of the BSS. Buffer information is information indicating the amount of packets to be transmitted stored by the base station or the terminal to communicate, that is, information indicating the buffer status of the packets to be transmitted.

[0162] In addition, communication type information is information indicating the type of communication, for example, whether the communication in the BSS is uplink or downlink, what guard interval (symbol length) is used for the signal to be transmitted and the coding scheme (such as LDPC (Low-Density Parity-Check) or BCC (Binary Convolutional Coding)) for the communication in the BSS.

[0163] Information related to the location and number of wireless communication terminals is, for example, information related to the number and location of wireless communication terminals to which frames (signals) are destined during communication in the BSS, in other words, information related to the number of slave terminals controlled by the base station and the location of the slave terminals.

[0164] The SR information related to BSS communication as described above can be used for communication based on spatial recycling in another BSS. In other words, the SR information includes information for spatial recycling, such as schedule information, resource information, transmission power information, modulation and coding scheme information, and allowed interference intensity information.

[0165] It should be noted that when communication in a BSS is determined to be executed, the SR information (that is, the SRinfo frame FL11) can be sent before or periodically during this communication.

[0166] In addition, in the case where the base station or the slave terminal starts communication of the base station or the slave terminal, the SR information can be sent simultaneously with or immediately before this communication. In addition, in the case of inviting a communication partner to start communication, that is, in the case of a trigger frame for sending an invitation signal to the communication partner, the base station can send the SR information to the control base station.

[0167] In addition, the SR information can be sent using a frame for notifying the SR information, or the SR information can be stored and sent in a frame sent for another purpose.

[0168] The SR info frame FL11 including such SR information stores the identifier of the phantom BSS1, and the SR info frame FL11 is transmitted in the second frequency band described above.

[0169] The control base station MAP1 that has received the SR info frame FL11 transmits control information to the base stations belonging to all the BBSs included in the phantom BSS1 other than the BSS1 that has transmitted the SR information and to the terminals, based on the SR information included in the SR info frame FL11. The control information is intended to control the communication in these BSSs.

[0170] In this example, the control base station MAP1 uses the second frequency band to transmit the frame FL12 including the SR information itself to the base station AP2 belonging to the BSS2 as control information. The frame FL12 includes an identifier indicating that the frame has been transmitted from the phantom BSS1, that is, the identifier of the phantom BSS1.

[0171] For example, the control information may be the same as at least a part of the SR information, or may be information obtained through appropriate calculations based on the SR information in the control base station. Here, for example, in the example shown in Figure 5 the information obtained through appropriate calculations may be the transmission power of the base station AP2 during communication calculated from the transmission power and position of the base station AP1 included as the SR information, the allowable interference intensity, etc.

[0172] Therefore, based on the SR information related to the communication in the BSS1 and received from the base station AP1 to communicate, the control base station MAP1 generates control information for controlling the communication using another BSS2, and transmits the control information to the base station AP2 in the BSS2. Therefore, in order to allow communication to be performed in the BSS2 as needed even when communication is being performed in the BSS1, the control base station MAP1 can control the communication in the BSS2.

[0173] In Figure 5 the example in, when transmitting the SR info frame FL11 including the SR information, the base station AP1 then realizes communication according to the information indicated by the SR information (such as the schedule and transmission power).

[0174] Here, the base station AP1 transmits the frame FL13 storing the predetermined data to the slave terminal STA1, and the slave terminal STA1 that has received the frame FL13 transmits an Ack frame FL14 indicating that the data has been correctly received to the base station AP1. In particular, the frame FL13 and the Ack frame FL14 are transmitted at the frequency indicated by the resource information in the SR information, and here, the frame FL13 and the Ack frame FL14 are transmitted in the first frequency band described above.

[0175] In addition, the base station or the slave terminal that has received the frame storing control information determines or calculates, based on the control information, the schedule, frequency resources or spatial resources, transmission power, modulation and coding scheme, allowable interference intensity, priority, communication type, etc. in the communication of the base station or the slave terminal. Then, the base station or the slave terminal performs communication in the BSS to which the base station or the slave terminal belongs based on the determination result or the calculation result.

[0176] In this example, the base station AP2 that has received the frame FL12 storing control information performs calculations as needed based on the control information to determine the schedule, frequency resources or spatial resources, transmission power, modulation and coding scheme, allowable interference intensity, priority, communication type, etc. in the communication in the BSS2 of the base station AP2.

[0177] Then, the base station AP2 sends the frame FL15 storing the predetermined data to the slave terminal STA2 according to the determination, and the slave terminal STA2 that has received the frame FL15 sends an Ack frame FL16 indicating that the data has been correctly received to the base station AP2. Here, for example, spatial reuse is used to send the frame FL15 and the Ack frame FL16 in the above-mentioned first frequency band.

[0178] It should be noted that in the case where it is inappropriate to perform communication in the BSS2 of the base station AP2 based on the control information, the base station AP2 can explicitly prohibit the communication of the base station AP2 or the slave terminal belonging to the BSS2. In this case, the base station AP2 prohibits the communication in the BSS2 of the base station AP2 during an appropriate time period (for example, before the communication in the BSS1 ends), and at an appropriate timing, sends a frame to also notify the slave terminal STA2 controlled by the base station AP2 of the indication that the communication in the BSS2 is about to be stopped.

[0179] Here, the case where it is inappropriate to perform communication in the BSS2 is, for example, the case where the BSS1 packet in the control information has a higher priority than the preset predetermined priority or the case where the communication in the BSS2 cannot be performed at an interference intensity equal to or lower than the allowable interference intensity of the communication in the BSS1 indicated by the control information.

[0180] Therefore, the base station AP2 determines the transmission power, etc. of the communication in the BSS2 to which the base station AP2 belongs based on the control information received from the control base station MAP1. Therefore, while suppressing interference in the slave terminal STA1 that receives the frame FL13 storing data, the base station AP2 can also achieve communication with the slave terminal STA2. In other words, according to the control information, the spatial reuse technology is used so as to be able to achieve more efficient communication.

[0181] It should be noted that when referring to Figure 5In the described example, the base station AP2 receives a frame including control information and transmits a frame including data to the slave terminal STA2. In contrast, of course, the slave terminal STA2 can receive a frame including control information and transmit a frame including data to the base station AP2.

[0182] In addition, in the example described with reference to Figure 5 the control base station MAP1 generates control information based on the SR information received from the base station AP1. However, the control base station MAP1 can generate control information based on the information included in the frame transmitted from the base station to the slave terminal or the information that can be observed for the communication.

[0183] In this case, for example, according to the sequence shown in Figure 6 the phantom BSS transmits control information related to the BSS communication, and the communication of the BSS is controlled based on the control information.

[0184] It should be noted that Figure 6 represents an example where in the phantom BSS1 shown in Figure 1 the control base station MAP1 controls the communication in BSS2.

[0185] In Figure 6 the character "master AP" represents the control base station MAP1, the character "AP1" represents the base station AP1, and the character "STA1" represents the slave terminal STA1. In addition, the character "AP2" represents the base station AP2, and the character "STA2" represents the slave terminal STA2.

[0186] First, in BSS1 or BSS2 included in the phantom BSS1, the base station or the slave terminal starts communication according to the normal communication process in the BSS.

[0187] In this example, the base station AP1 transmits a frame FL21 storing predetermined data to the slave terminal STA1, and the slave terminal STA1 that has received the frame FL21 transmits an Ack frame FL22 indicating that the data has been correctly received to the base station AP1. Here, the frame FL21 and the Ack frame FL22 are transmitted in the above-mentioned first frequency band.

[0188] In addition, the frame FL21 may include information related to the communication between the base station AP1 and the slave terminal STA1 in BSS1. In other words, at least part of the above-mentioned SR information can be included in, for example, the SIG-A field of the physical header of the frame FL21.

[0189] Specifically, the information related to the communication in BSS1 included in frame FL21 may include the identifier of the base station or the slave terminal to communicate, schedule information, resource information, transmission power information, modulation and coding scheme information, allowable interference intensity information, priority, buffer information, communication type information, information related to the location and number of wireless communication terminals, etc.

[0190] When the communication in BSS1 is detected (in other words, the transmission of frame FL21), the control base station MAP1 receives frame FL21 and reads the information related to the communication in BSS1 included in the received frame FL21. In addition, the control base station MAP1 appropriately observes the information related to the communication in BSS1 for the communication in BSS1. For example, by observing the transmission power in frame FL21, etc., the control base station MAP1 can estimate the transmission power of frame FL21.

[0191] The control base station MAP1 generates control information similar to the control information in the case of Figure 5 based on the information related to the communication in BSS1 read from frame FL21 and the information obtained by observing the communication in BSS1, and sends a frame including the control information to the base station AP2 or the slave terminal STA2 in BSS2. Here, the control base station MAP1 sends frame FL23 including the generated control information to the base station AP2 in the above second frequency band.

[0192] It should be noted that, as in the case of Figure 5 , the control information may be at least part of the information related to the communication in BSS1 read from frame FL21 or the information obtained by observing the communication in BSS1. In addition, as in the case of Figure 5 , the control information may be information obtained by appropriate calculation based on the information related to the communication in BSS1 read from frame FL21 or the information obtained by observing the communication in BSS1.

[0193] When receiving frame FL23 sent from the control base station MAP1, the base station AP2 performs appropriate calculations based on the control information stored in frame FL23 to determine the schedule, frequency resource or spatial resource, transmission power, modulation and coding scheme, allowable interference intensity, priority, communication type, etc. for the communication in BSS2 of the base station AP2.

[0194] Then, the base station AP2 sends frame FL24 storing predetermined data to the slave terminal STA2 according to the determination, and the slave terminal STA2 that has received frame FL24 sends an Ack frame FL25 indicating that the data has been correctly received to the base station AP2. Here, for example, spatial reuse is used to send frame FL24 and Ack frame FL25 in the above first frequency band.

[0195] Note that, as in the case of Figure 5 when it is determined that communication in BSS2 of base station AP2 is inappropriate based on control information, base station AP2 can explicitly prohibit communication from the base station AP2 belonging to BSS2 or from the terminal.

[0196] Therefore, base station AP2 determines a schedule, transmission power, etc. for communication in BSS2 to which base station AP2 belongs based on the control information received from control base station MAP1. Therefore, while suppressing interference in terminal STA1 that receives frame FL21 storing data, base station AP2 can also achieve communication with terminal STA2. In other words, according to the control information, space reuse technology is used to enable more efficient communication.

[0197] Note that, in the example described with reference to Figure 6 base station AP2 receives a frame including control information and transmits a frame including data to terminal STA2. In contrast, of course, terminal STA2 can receive a frame including control information and transmit a frame including data to base station AP2.

[0198] <Frame Format for Communication in Phantom BSS>

[0199] Now, the frame format for communication in phantom BSS will be described.

[0200] For example, the format of a frame for communication in phantom BSS is as shown in Figure 7 .

[0201] Here, frames for communication in BSS include, for example, the primary beacon frame, primary probe request frame, primary probe response frame, primary authentication request frame, primary authentication response frame, primary association request frame, primary association response frame, STA info frame, primary APinfo frame, frame storing SR information, and frame storing control information as described above.

[0202] In Figure 7 the arrow W11 indicates an example where the identifier (primary cell ID) of the phantom BSS is stored in the physical header, and the arrow W12 indicates an example where the identifier of the phantom BSS is stored in the physical payload (MAC).

[0203] Specifically, in the example indicated by arrow W11, a frame for communication in phantom BSS includes a physical header (Phy header) indicated by arrow Q11 arranged in the header of the frame, and the physical header is followed by a physical payload (Phy payload) indicated by arrow Q12.

[0204] The physical header includes a CRC (Cyclic Redundancy Check) added to the end of the header, and thus, a receiver of a control base station, a base station, a slave terminal, etc., which receives a frame transmitted in the phantom BSS, can check the content described in the physical header at the time point when the receiver receives the physical header instead of receiving the entire frame.

[0205] The physical header indicated by the arrow Q11 includes an L-STF (Legacy Short Training Field), an L-LTF (Legacy Long Training Field), an L-SIG (Legacy Signal Field), and an MC-SIG-A (Master Cell Signal Field) arranged in this order from the head of the physical header.

[0206] L-SIF and L-LTF are fields that store training signals, and L-SIG is a signal field that stores rate information and length information in the data part.

[0207] In addition, the MC-SIG-A following the L-SIG is a signal field (area) that stores information related to communication in the BSS, for example. In this example, the MC-SIG-A stores the master cell Id as an identifier of the phantom BSS. In particular, here, the shaded area represents the area that stores the master cell ID. It should be noted that the master cell ID of the phantom BSS stored in the MC-SIG-A can be part of the identifier information.

[0208] In addition, the physical payload indicated by the arrow Q12 following the physical header includes one or more MAC payloads (data areas) that store data to be transmitted, and includes a MAC header, and each MAC header is added to the head of the corresponding MAC payload. The MAC header includes information indicating the source and destination of the data, in other words, information indicating the source and destination (address) of the frame indicated by the arrow W11.

[0209] In the phantom BSS, for example, a frame including a physical header containing an identifier (master cell ID) of the phantom BSS is used for communication in the phantom BSS. Therefore, at the time point when a control base station, a base station, or a slave terminal receives a frame up to the end of the physical header instead of receiving the entire frame, another device in the phantom BSS (that is, a control base station, a base station, or a slave terminal) can detect that the frame has been transmitted from the phantom BSS.

[0210] In the case where the identifier assigned to the BSS included in the phantom BSS is used as the identifier of the phantom BSS, the identifier of the phantom BSS can be stored in the Partial AID field of the VHT-SIG-A specified in IEEE (Institute of Electrical and Electronics Engineers) 802.11-2016 or the BSS Color field of the HE-SIG-A specified in IEEE 802.11ax.

[0211] In contrast, for example, even when the identifier (primary cell ID) of the phantom BSS indicated by arrow W12 is stored in the physical payload, the frame basically has a structure similar to that in the example indicated by arrow W11.

[0212] Specifically, in the example indicated by arrow W12, the physical header (Phy header) indicated by arrow Q21 is arranged at the head of the frame, and the part following the physical header corresponds to the physical payload (Phy payload) indicated by arrow Q22.

[0213] The physical header basically has a structure similar to that in the example indicated by arrow W11, but does not store the identifier of the phantom BSS.

[0214] In addition, the physical payload includes one or more MAC payloads for storing data to be transmitted, and the MAC payload includes at least one frame or field for storing the identifier (primary cell ID) of the phantom BSS. In addition, the physical payload includes a MAC header, each MAC header being added to the head of the corresponding MAC payload, and the MAC header includes information indicating the source and destination of the data.

[0215] Compared with the physical header, a modulation and coding scheme with a higher degree of modulation can be used for the physical payload. Therefore, storing the identifier of the phantom BSS in the physical payload can reduce the length of the identifier on the time axis, allowing suppression of wasteful use of communication resources.

[0216] As described above, according to the present technology, in a wireless network in which multiple base stations are connected together by a wired method or the like, the use of the primary beacon frame including the identifier of the phantom BSS allows the autonomous construction of a phantom BSS that is not pre-designed. In other words, multiple low-level wireless networks (BSSs) that are not pre-designed can be used to construct a phantom BSS corresponding to a high-level wireless network.

[0217] The phantom BSS is a high-level network that includes: a large number of small BSSs, using a higher frequency band; and a control base station that integrates and controls the BSSs through communication in a lower frequency band. Such a phantom BSS can achieve an appropriate communication capacity and coverage area.

[0218] In addition, in the phantom BSS, the control base station is connected to the base stations that construct the BSS, and can thus collect information related to communication with the BSS. Then, the control base station generates control information based on the information related to communication with the BSS thus collected, and can thus control communication in another BSS. This allows prevention of possible signal interference between BSSs that communicate independently of each other.

[0219] In this case, while communication is being performed in one of the BBSs, communication can be performed in other BBSs, allowing efficient use of communication resources.

[0220] In addition, a signal (frame) sent by a control base station and used as a phantom BSS stores an identifier of the phantom BSS. Thus, for multiple phantom BSSs, a control base station included in each phantom BSS can identify a signal from another phantom BSS and end reception of the signal. Therefore, the control base station can send a signal (frame) of the phantom BSS from the control base station, can achieve efficient use of communication resources between the phantom BSSs, and allows suppression of wasted power consumption.

[0221] Similarly, in a BBS configured by base stations connected to a control base station of a phantom BSS, a signal from another phantom BSS can be identified and reception of the signal can be ended. Therefore, the BSS can effectively use communication resources while suppressing wasted power consumption.

[0222] In particular, in a case where a phantom BSS has a large coverage area and a signal (frame) from the phantom BSS reaches a far position, a large number of BSSs are affected by the signal. Therefore, the effect of ending reception of unnecessary signals is more significant.

[0223] <Description of phantom BSS construction process>

[0224] Now, processing performed when the above wireless communication device 11 serves as a control base station, a base station, or a slave terminal will be described.

[0225] First, phantom BSS construction processing performed when the wireless communication device 11 serving as a control base station constructs a phantom BSS according to the sequence described with reference to Figure 4 will be described. In other words, the phantom BSS construction processing performed by the wireless communication device 11 will be described with reference to the flowchart in Figure 8 .

[0226] In step S11, the communication unit 23 transmits a primary beacon frame via the antenna 24, more specifically, a packet including the primary beacon frame.

[0227] Specifically, under the control of the control unit 22, the data processing unit 21 generates a primary beacon frame in a format indicated by arrows W11 and W12 in Figure 7 , and the primary beacon frame includes an identifier of the phantom BSS and operation and function information related to the operation and function of the phantom BSS.

[0228] In addition, the primary beacon frame includes an identifier of the wireless communication device 11 itself serving as a control base station as information indicating a source, and includes destination information indicating, for example, a broadcast address as information indicating a destination.

[0229] The data processing section 21 supplies a primary beacon frame (packet) from the set of sections from the modulation and demodulation section 31 to the wireless interface section 34 to the amplifier section 35. Further, the amplifier section 35 amplifies the transmission signal corresponding to the primary beacon frame supplied from the wireless interface section 34, and then wirelessly transmits the amplified signal in the second frequency band through the antenna 24, thereby transmitting the primary beacon frame.

[0230] Accordingly, a base station or an unassociated STA within the range where the base station or the unassociated STA can communicate with the wireless communication device 11 receives the primary beacon frame, and based on the primary beacon frame, performs the process in step S42 described below to transmit a primary probe request frame to notify the presence of the base station or the unassociated STA. Figure 9 to notify the presence of the base station or the unassociated STA.

[0231] Then, frame exchange is performed between the wireless communication device 11 acting as a control base station and the base station or the unassociated STA for the construction of the phantom BSS1 and the connection to the phantom BSS1. Specifically, the control section 22 controls the frame exchange for the construction and connection to the phantom BSS1, thereby causing the processes in subsequent steps S12 to S17 to be performed.

[0232] In step S12, the communication section 23 receives a primary probe request frame transmitted from each of one or more base stations or unassociated STAs through the antenna 24.

[0233] In other words, the amplifier section 35 of the communication section 23 receives the received signal (packet) corresponding to the primary probe request frame through the antenna 24, and supplies the signal to the control section 22 through the set of sections from the wireless interface section 34 to the data processing section 21.

[0234] Accordingly, the control section 22 identifies the presence of a base station or an unassociated STA within the range where the base station or the unassociated STA can connect to the wireless communication device 11 from the identifier of the base station or the unassociated STA included in the primary probe request frame which is information indicating the source of the received primary probe request frame.

[0235] When the presence of the base station or the unassociated STA is identified, the control section 22 controls the data processing section 21 to generate and cause the data processing section 21 to generate, for example, a primary probe response frame including the identifier of the phantom BSS in the format indicated by the arrow W11 or the arrow W12 in Figure 7 to generate a primary probe response frame including the identifier of the phantom BSS.

[0236] Under the control of the control section 22, the data processing section 21 generates a primary probe response frame indicating that the control base station has confirmed the presence of the base station or the unassociated STA, and supplies the primary probe response frame to the amplifier section 35 through the set of sections from the modulation and demodulation section 31 to the wireless interface section 34.

[0237] In step S13, the amplifier section 35 amplifies the transmission signal corresponding to the primary probe response frame provided from the wireless interface section 34, and then wirelessly transmits the amplified signal in the second frequency band via the antenna 24, thereby transmitting the primary probe response frame to the base station or an unassociated STA.

[0238] Then, the base station or the unassociated STA that has received the primary probe response frame performs the process in step S44 described below Figure 9 to transmit a primary verification request frame for requesting the wireless communication device 11 serving as the control base station to verify the base station or the unassociated STA.

[0239] In step S14, the communication section 23 receives, via the antenna 24, the primary verification request frames transmitted from each of one or more base stations or unassociated STAs.

[0240] Specifically, the amplifier section 35 of the communication section 23 receives, via the antenna 24, the received signal (packet) corresponding to the primary verification request frame, and supplies the signal to the control section 22 via the set of sections from the wireless interface section 34 to the data processing section 21.

[0241] Based on the received primary verification request frame, the control section 22 verifies the base station or the unassociated STA corresponding to the source of the primary verification request frame. Then, when the base station or the unassociated STA is correctly verified, the control section 22 controls the data processing section 21 to generate, for example, a primary verification response frame including the identifier of the phantom BSS in the format indicated by Figure 7 arrow W11 or arrow W12 in.

[0242] Under the control of the control section 22, the data processing section 21 generates a primary verification response frame indicating that the base station or the unassociated STA has been verified, and supplies the primary verification response frame to the amplifier section 35 via the set of sections from the modulation and demodulation section 31 to the wireless interface section 34.

[0243] In step S15, the amplifier section 35 amplifies the transmission signal corresponding to the primary verification response frame provided from the wireless interface section 34, and then wirelessly transmits the amplified signal in the second frequency band via the antenna 24, thereby transmitting the primary verification response frame to the base station or the unassociated STA.

[0244] Then, the base station or the unassociated STA that has received the primary verification response frame performs the process in step S46 described below Figure 9 to transmit a primary association request frame for requesting the wireless communication device 11 serving as the control base station to connect to the base station or the unassociated STA.

[0245] In step S16, the communication section 23 receives, via the antenna 24, a primary association request frame transmitted from each of one or more base stations or unassociated STAs.

[0246] Specifically, an amplifier section 35 of the communication section 23 receives, via the antenna 24, a received signal (packet) corresponding to the primary association request frame, and supplies the signal to the control section 22 via the set of sections from the radio interface section 34 to the data processing section 21.

[0247] Based on the received primary association request frame, the control section 22 connects to the base station or unassociated STA corresponding to the source of the primary association request frame. Specifically, the control section 22 controls the data processing section 21 and causes the data processing section 21 to generate, for example, a primary association response frame including an identifier of the phantom BSS in a format indicated by arrow W11 or arrow W12 in Figure 7 .

[0248] Under the control of the control section 22, the data processing section 21 generates a primary association response frame indicating that the connection is permitted, and supplies the primary association response frame to the amplifier section 35 via the set of sections from the modulation and demodulation section 31 to the radio interface section 34.

[0249] In step S17, the amplifier section 35 amplifies a transmission signal corresponding to the primary association response frame supplied from the radio interface section 34, and then wirelessly transmits the amplified signal via the antenna 24 in the second frequency band, thereby transmitting the primary association response frame to the base station or unassociated STA.

[0250] In addition, when the base station or unassociated STA receives the primary association response frame and thus connects to the wireless communication device 11 serving as the control base station, the base station transmits an STA info frame including STA information about the slave terminals controlled by the base station.

[0251] The STA info frame is transmitted by the processing in step S48 described below, Figure 9 but may be transmitted spontaneously from the base station or in response to a request from the control base station.

[0252] In step S18, the communication section 23 receives, via the antenna 24, the STA info frame transmitted from the base station.

[0253] Specifically, an amplifier section 35 of the communication section 23 receives, via the antenna 24, a received signal (packet) corresponding to the STA info frame, and supplies the signal to the control section 22 via the set of sections from the radio interface section 34 to the data processing section 21.

[0254] When the STA info frame is provided to the control section 22 in this way, the control section 22 can obtain, from the STA information included in the STA info frame, the type and identifier of the slave terminal controlled by the base station, the function information, and the location-related information, and thus connect to the slave terminal.

[0255] When the wireless communication device 11 used as the control base station is connected to the base station, the unassociated STA, or the slave terminal as described above, the phantom BSS is constructed, and the phantom BSS construction process ends.

[0256] It should be noted that, in the above example, the phantom BSS is constructed according to the sequence shown in Figure 4 , but in the case where the phantom BSS is constructed according to the sequence shown in Figure 3 , the processes in steps S11 to S17 are executed as the phantom BSS construction process.

[0257] In this case, in steps S13, S15, and S17, each frame is transmitted not only using the base station or the unassociated STA but also using the slave terminal set as the destination, and the base station, the unassociated STA, or the slave terminal is directly connected to the wireless communication device 11 used as the control base station. Additionally, in this case, the process in step S18 is not executed.

[0258] Furthermore, in the case where the phantom BSS is constructed according to the sequence shown in Figure 3 or the sequence shown in Figure 4 , the check sequence can be executed before or after the phantom BSS construction process or during the phantom BSS construction process.

[0259] In this case, the control section 22 controls the data processing section 21 or the communication section 23 to control the execution of the check sequence.

[0260] Specifically, under the control of the control section 22, the data processing section 21 generates a capability check request frame and provides the capability check request frame to the amplifier section 35 via the set of sections from the modulation and demodulation section 31 to the wireless interface section 34. The amplifier section 35 amplifies the transmission signal corresponding to the capability check request frame provided from the wireless interface section 34 and then wirelessly transmits the amplified signal in the second frequency band through the antenna 24, thus transmitting the request frame to the base station, the unassociated STA, or the slave terminal.

[0261] Then, the base station, the unassociated STA, or the slave terminal transmits a capability check response frame indicating the result of the check (such as an operation check).

[0262] The amplifier section 35 of the communication section 23 receives a response frame (more specifically, a received signal (packet) corresponding to the response frame) via the antenna 24, and supplies the signal to the control section 22 via the set of sections from the wireless interface section 34 to the data processing section 21.

[0263] When the capability check response frame is thus supplied to the control section 22, the control section 22 can know from the response frame that the check of the configuration and operation of the phantom BSS has been performed.

[0264] In addition, after the phantom BSS is configured, the wireless communication device 11 serving as the control base station can invite the slave terminals connected to the wireless communication device 11 or unassociated STAs to connect to a predetermined base station. In this case, for example, the control section 22 determines the base station corresponding to the new connection destination of the slave terminal according to the spatial position relationship between the base station identified from, for example, the STA information about the slave terminal and the slave terminal. Similarly, for example, the control section 22 determines the base station corresponding to the connection destination of the unassociated STA according to the spatial position relationship between the base station and the unassociated STA.

[0265] When the base station corresponding to the connection destination of the slave terminal or the unassociated STA is determined, the control section 22 controls the data processing section 21 according to the determination result so that the data processing section 21 generates a frame for inviting connection to the base station and including information related to the base station (such as the identifier of the determined base station).

[0266] Under the control of the control section 22, the data processing section 21 generates a frame for inviting connection to the base station, and supplies the frame to the amplifier section 35 via the set of sections from the modulation and demodulation section 31 to the wireless interface section 34. The amplifier section 35 amplifies the transmission signal corresponding to the frame supplied from the wireless interface section 34, and then transmits the amplified signal via the antenna 24 in the second frequency band, thereby transmitting a frame for inviting connection to the base station to the unassociated STA or the slave terminal.

[0267] Then, the unassociated STA or the slave terminal that has received the frame for inviting connection to the base station performs an appropriate frame exchange with the base station according to the information included in the received frame, and connects to the base station designated by the wireless communication device 11 serving as the control base station.

[0268] As described above, the wireless communication device 11 serving as the control base station transmits the master beacon frame including the identifier of the phantom BSS, and performs a frame exchange with the base station or the unassociated STA to configure the phantom BSS. Therefore, the phantom BSS that is not pre-designed can be autonomously configured.

[0269] <Description of connection processing>

[0270] Now, a description will be given when referring to Figure 8The described phantom BSS configuration process performs the connection process executed by the wireless communication device 11 acting as a base station or an unassociated STA. Here, as an example, refer to Figure 9 in the flowchart, and describe the connection process corresponding to the sequence described and executed by the wireless communication device 11 acting as a base station with reference to Figure 4 and executed by the wireless communication device 11 acting as a base station.

[0271] In step S41, the communication section 23 performs Figure 8 the process in step S11 in

[0272] to receive the primary beacon frame sent from the control base station through the antenna 24. Specifically, the amplifier section 35 of the communication section 23 receives the received signal (packet) corresponding to the primary beacon frame through the antenna 24, and provides the signal to the control section 22 via the set of sections from the radio interface section 34 to the data processing section 21.

[0273] Accordingly, the control section 22 can know what kind of network the phantom BSS is and the control base station that controls the phantom BSS from the identifier of the phantom BSS, the identifier of the control base station, and the operation and function information about the phantom BSS included in the received primary beacon frame.

[0274] In the case where it is determined that the wireless communication device 11 is going to connect to the control base station for the phantom BSS, the control section 22 controls the frame exchange performed between the wireless communication device 11 and the control base station for the configuration and connection of the phantom BSS1. This enables the execution of the processes in subsequent steps S42 to S47.

[0275] Specifically, the control section 22 controls the data processing section 21 and causes the data processing section 21 to generate, for example, a primary probe request frame including the identifier of the phantom BSS in the format indicated by the arrow W11 or the arrow W12 in Figure 7 . The primary probe request frame also includes the identifier of the wireless communication device 11 acting as a base station as the information indicating the source.

[0276] Under the control of the control section 22, the data processing section 21 generates a primary probe request frame notifying the existence of the wireless communication device 11, and provides the primary probe request frame to the amplifier section 35 via the set of sections from the modulation and demodulation section 31 to the radio interface section 34.

[0277] In step S42, the amplifier section 35 amplifies the transmission signal corresponding to the primary probe request frame provided from the radio interface section 34, and then transmits the amplified signal through the antenna 24 in the second frequency band, thereby sending the primary probe request frame to the control base station.

[0278] Then, the control base station performs Figure 8The process in step S13 is performed to send a primary probe response frame.

[0279] In step S43, the amplifier section 35 receives the primary probe response frame transmitted from the control base station via the antenna 24, and supplies the primary probe response frame to the control section 22 through the set of sections from the slave radio interface section 34 to the data processing section 21.

[0280] When the primary probe response frame is received, the control section 22 controls the data processing section 21 according to the primary probe response frame so that the data processing section 21 generates, for example, a primary authentication request frame including the identifier of the phantom BSS in the format indicated by the arrow W11 or the arrow W12 in Figure 7

[0281] Under the control of the control section 22, the data processing section 21 generates a primary authentication request frame for requesting authentication, and supplies the primary authentication request frame to the amplifier section 35 through the set of sections from the modulation and demodulation section 31 to the radio interface section 34.

[0282] In step S44, the amplifier section 35 amplifies the transmission signal corresponding to the primary authentication request frame supplied from the radio interface section 34, and then transmits the amplified signal in the second frequency band via the antenna 24, thereby sending the primary authentication request frame to the control base station.

[0283] Then, the control base station performs Figure 8 the process in step S15 in to send a primary authentication response frame, and thus, the process in step S45 is performed.

[0284] Specifically, in step S45, the amplifier section 35 receives the primary authentication response frame transmitted from the control base station via the antenna 24, and supplies the primary authentication response frame to the control section 22 through the set of sections from the radio interface section 34 to the data processing section 21.

[0285] When the primary authentication response frame is received, the control section 22 controls the data processing section 21 according to the primary authentication response frame so that the data processing section 21 generates, for example, a primary association request frame including the identifier of the phantom BSS in the format indicated by the arrow W11 or the arrow W12 in Figure 7

[0286] Under the control of the control section 22, the data processing section 21 generates a primary association request frame for requesting connection, and supplies the primary association request frame to the amplifier section 35 through the set of sections from the modulation and demodulation section 31 to the radio interface section 34.

[0287] In step S46, the amplifier section 35 amplifies the transmission signal corresponding to the main association request frame provided from the wireless interface section 34, and then wirelessly transmits the amplified signal in the second frequency band through the antenna 24, thereby transmitting the main association request frame to the control base station.

[0288] In addition, the control base station executes Figure 8 the process in step S17 in

[0289] to transmit the main association response frame.

[0290] In addition, the control section 22 appropriately provides the STA information to the data processing section 21, controls the data processing section 21, and causes the data processing section 21 to generate a STAinfo frame including the STA information of the slave terminal controlled by the wireless communication device 11. Under the control of the control section 22, the data processing section 21 generates a STA info frame and provides the STA info frame to the amplifier section 35 through the set of sections from the modulation and demodulation section 31 to the wireless interface section 34.

[0291] It should be noted that, as described above, the STA info frame can be spontaneously generated by the wireless communication device 11 acting as a base station or generated in response to a request from the control base station.

[0292] In step S48, the amplifier section 35 amplifies the transmission signal corresponding to the STA info frame provided from the wireless interface section 34, and then wirelessly transmits the amplified signal in the second frequency band through the antenna 24, thereby transmitting the STAinfo frame to the control base station.

[0293] In addition, the control section 22 appropriately provides information related to the control base station (such as the information included in the main beacon frame received in step S41) to the data processing section 21 as control base station information, controls the data processing section 21, and causes the data processing section 21 to generate a main AP info frame. Under the control of the control section 22, the data processing section 21 generates a main APinfo frame including the control base station information and provides the main AP info frame to the amplifier section 35 through the set of sections from the modulation and demodulation section 31 to the wireless interface section 34.

[0294] In step S49, the amplifier section 35 amplifies the transmission signal corresponding to the master APinfo frame provided from the wireless interface section 34, and then wirelessly transmits the amplified signal via the antenna 24, thereby transmitting the master AP info frame to the slave terminal controlled by the wireless communication device 11.

[0295] When the wireless communication device 11 serving as a base station connects to the control base station and performs frame transmission with the control base station and the slave terminal to connect the control base station and the slave terminal, a phantom BSS is constructed and the connection process ends.

[0296] As described above, when receiving the master beacon frame including the identifier of the phantom BSS, the wireless communication device 11 serving as a base station performs frame exchange with the control base station to connect to the control base station. In addition, the wireless communication device 11 transmits the STAinfo frame to the control base station and simultaneously transmits the master AP info frame to the slave terminal, thereby connecting the control base station and the slave terminal. This allows the phantom BSS that is not pre-designed to be autonomously constructed.

[0297] It should be noted that, in the above example, the phantom BSS is constructed according to the sequence shown in Figure 4 However, in the case of constructing the phantom BSS according to the sequence shown in Figure 3 the processes in steps S41 to S47 are executed as the connection process. In this case, the processes in steps S41 to S47 are executed as the connection process not only in the base station but also in the wireless communication device 11 serving as an unassociated STA or a slave terminal.

[0298] In addition, in the case of constructing the phantom BSS according to the sequence shown in Figure 3 or the sequence shown in Figure 4 the check sequence can be executed before or after or during the connection process.

[0299] In this case, the control section 22 controls the data processing section 21 or the communication section 23 to control the execution of the check sequence.

[0300] Specifically, the amplifier section 35 receives the capability check request frame transmitted from the control base station via the antenna 24, and provides the request frame to the control section 22 through the set of sections from the wireless interface section 34 to the data processing section 21.

[0301] Then, based on the information related to the phantom BSS included in the request frame, the control section 22 performs checks such as whether signal transmission and reception can be performed, checks of communication operations in the phantom BSS, etc., and controls the generation of the capability check response frame indicating the check result.

[0302] Under the control of the control section 22, the data processing section 21 generates a capability check response frame and supplies a capability check request frame to the amplifier section 35 via the set of sections from the modulation and demodulation section 31 to the wireless interface section 34. The amplifier section 35 amplifies the transmission signal corresponding to the response frame supplied from the wireless interface section 34 and then wirelessly transmits the amplified signal in the second frequency band through the antenna 24, thereby transmitting the response frame to the control base station.

[0303] In addition, when the wireless communication device 11 acting as an unassociated STA or a slave terminal executes the processes in steps S41 to S47 as connection processing, the control base station transmits a frame for inviting connection to a specified base station after the construction of the phantom BSS.

[0304] In this case, the control section 22 of the wireless communication device 11 acting as an unassociated STA or a slave terminal controls the data processing section 21 and the communication section 23 to control the connection to the base station specified by the control base station.

[0305] Specifically, the amplifier section 35 receives the frame transmitted from the control base station through the antenna 24 and supplies the frame to the control section 22 via the set of sections from the wireless interface section 34 to the data processing section 21. Then, based on the information related to the base station specified as the connection destination (this information is included in the received frame), the control section 22 controls the execution of frame exchange for connecting to this base station, etc.

[0306] <Description of BSS communication control processing>

[0307] When the phantom BSS is constructed through the above processing, the control base station controls the communication in each BSS included in the phantom BSS. For example, the control base station controls the communication in the BSS according to Figure 5 the sequence shown in

[0308] Referring to Figure 10 the flowchart in Figure 5 the BSS communication control processing executed by the wireless communication device 11 acting as the control base station will be described in the case of controlling the communication in the BSS according to the sequence shown in

[0309] In step S81, the amplifier section 35 receives an SR info frame transmitted from the base station in a predetermined BSS included in the phantom BSS through the antenna 24 and supplies the SR info frame to the control section 22 via the set of sections from the wireless interface section 34 to the data processing section 21.

[0310] Here, the following description assumes that the wireless communication device 11 acts as Figure 1The control base station MAP1 shown in , and in step S81, the base station AP1 in BSS1 sends an SR info frame.

[0311] In step S82, the control section 22 generates control information regarding BSS2 that is different from BSS1 including the base station AP1.

[0312] For example, the control section 22 generates control information based on the SR information included in the SR info frame received from the base station AP1 and the information obtained through the calculation regarding the SR information, and provides the generated information to the data processing section 21.

[0313] In addition, the control section 22 causes the data processing section 21 to generate a frame for controlling communication in BSS2 and including the control information and the identifier of the phantom BSS1. Under the control of the control section 22, the data processing section 21 generates a frame including the control information, and provides the frame to the amplifier section 35 via the set of sections from the modulation and demodulation section 31 to the wireless interface section 34.

[0314] In step S83, the amplifier section 35 amplifies the transmission signal corresponding to the frame including the control information and provided from the wireless interface section 34, and then wirelessly transmits the amplified signal in the second frequency band via the antenna 24, thus transmitting the frame to the base station AP2 in BSS2 or from the terminal STA2. When the frame including the control information is transmitted, the BSS communication control process ends.

[0315] The base station AP2 or the terminal STA2 that has received the frame including the control information performs communication in BSS2 according to the control information, and thus, the communication in BSS2 is controlled.

[0316] As described above, the wireless communication device 11 serving as the control base station receives an SR info frame from the predetermined BSS, generates control information based on the SR information included in the SR info frame, and transmits a frame including the generated control information to the base station belonging to another BSS or from the terminal. Therefore, the control information based on the information related to the communication in the predetermined BSS is used to control the communication in another BSS, and more efficient communication can be achieved.

[0317] <Description of the BSS communication process on the SR information transmission side>

[0318] In addition, in the case of performing the BSS communication control process described with reference to Figure 10 the side that sends the SR info frame performs the process shown in Figure 11 .

[0319] Figure 11The BSS communication processing on the SR information transmission side shown can be performed by a base station or by a slave terminal. Here, it is assumed that the base station AP1 performs the BSS communication processing on the SR information transmission side according to Figure 5 the sequence shown.

[0320] Referring to Figure 11 the flowchart in, the BSS communication processing on the SR information transmission side performed by the wireless communication device 11 serving as the base station AP1 will be described.

[0321] When the BSS communication processing on the SR information transmission side starts, first, the control section 22 controls the transmission of a frame including SR information (communication information) related to communication in the BSS1 to which the wireless communication device 11 belongs to the control base station MAP1.

[0322] In other words, in step S111, the data processing section 21 generates an SRinfo frame including SR information.

[0323] Specifically, the control section 22 generates SR information and provides the SR information to the data processing section 21, and controls the data processing section 21 to cause the data processing section 21 to generate an SR info frame. Under the control of the control section 22, the data processing section 21 generates an SR info frame including SR information, and provides the SRinfo frame to the amplifier section 35 via the set of sections from the modulation and demodulation section 31 to the wireless interface section 34.

[0324] In step S112, the amplifier section 35 amplifies the transmission signal corresponding to the SR info frame provided from the wireless interface section 34, and then wirelessly transmits the amplified signal in the second frequency band through the antenna 24, thereby transmitting the SRinfo frame to the control base station MAP1.

[0325] In step S113, the data processing section 21 generates a frame including data.

[0326] Specifically, the control section 22 controls the data processing section 21 to cause the data processing section 21 to generate a frame including the data to be transmitted to the slave terminal STA1. Under the control of the control section 22, the data processing section 21 generates a frame including the data to be transmitted to the slave terminal STA1, and provides the frame to the amplifier section 35 via the set of sections from the modulation and demodulation section 31 to the wireless interface section 34.

[0327] In step S114, the amplifier section 35 amplifies the transmission signal corresponding to the frame including data and provided from the wireless interface section 34, and then wirelessly transmits the amplified signal in the first frequency band through the antenna 24, thus transmitting the frame to the slave terminal STA1. Further, when the frame is received from the slave terminal STA1, the slave terminal STA1 transmits an Ack frame. Accordingly, the wireless communication device 11 receives the Ack frame, and the communication in the BSS1 ends.

[0328] When the frame including data is transmitted to the slave terminal STA1 in this way, the BSS communication process on the SR information transmission side ends.

[0329] As described above, the wireless communication device 11 acting as a base station transmits an SR info frame to the control base station and performs communication in the BSS of the wireless communication device 11. By transmitting the SR info frame to the control base station in this way, the control base station can control the communication in another BSS based on the SR information and can perform more efficient communication.

[0330] <Description of the BSS communication process on the control information receiving side>

[0331] In addition, in the case of the BSS communication control process described with reference to Figure 10 the side that receives the frame including the control information performs the process shown in Figure 12 .

[0332] Figure 12 The BSS communication process on the control information receiving side shown in can be performed by the base station or by the slave terminal. Here, it is assumed that the base station AP2 performs the BSS communication process on the control information receiving side according to the sequence shown in Figure 5 .

[0333] With reference to Figure 12 the flowchart in , the BSS communication process on the control information receiving side performed by the wireless communication device 11 acting as the base station AP2 will be described.

[0334] In step S141, the amplifier section 35 receives the frame including the control information and transmitted from the control base station MAP1 through the antenna 24, and provides the frame to the control section 22 through the set of parts from the wireless interface section 34 to the data processing section 21.

[0335] When the frame including the control information is received as described above, the control section 22 performs the processes in subsequent steps S142 to S144 based on the control information to control the communication in the BSS2 to which the wireless communication device 11 belongs.

[0336] Specifically, in step S142, the control section 22 also appropriately performs calculations based on the control information included in the frame received in step S141 to determine information related to communication in BSS2 to which the wireless communication device 11 belongs.

[0337] For example, the control section 22 determines a schedule for communication in BSS2, frequency resources or spatial resources, transmission power, modulation and coding schemes, allowable interference intensity, priority, communication type, etc. as information related to communication in BSS2.

[0338] When determining information related to communication in BSS2, the control section 22 controls communication in BSS2 according to the determination result.

[0339] Specifically, based on the information determined in step S142, the processes in subsequent steps S143 and S144 are executed, and the BSS communication process on the control information receiving side ends. It should be noted that the processes in steps S143 and S144 are similar to Figure 11 the processes in steps S113 and S114, except that the destination of the transmitted frame is from the terminal STA2 instead of from the terminal STA1, and therefore, the description of this process is omitted.

[0340] However, in step S144, for example, the control section 22 controls the operations of each part according to the schedule determined in step S142, or transmits a frame such that the frequency resources or spatial resources, transmission power, modulation and coding schemes, communication type, etc. determined in step S142 are used.

[0341] As described above, the wireless communication device 11 acting as a base station determines information related to communication in BSS2 based on the control information included in the frame received from the control base station MAP, and controls communication in BSS2 based on the determination result. By thus determining information related to communication in BSS2 according to the control information, communication in the BSS of the wireless communication device 11 can be performed more efficiently while taking into account communication in another BSS.

[0342] <Description of BSS communication control process>

[0343] Incidentally, in the BSS communication control process described with reference to Figure 10 it is described that the control base station receives an SR info frame from the base station to generate control information. However, the control base station can generate control information based on information about communication in the BSS that the control base station can obtain without the transmission of the SR info frame.

[0344] In this case, the wireless communication device 11 acting as the control base station performs, for exampleFigure 13 The BSS communication control process shown in Figure 13 the flowchart in Figure 1 will be described for the BSS communication control process performed by the wireless communication device 11 serving as the control base station. In particular, it is assumed here that: the wireless communication device 11 serves as Figure 6 the control base station MAP1 shown in

[0345] In step S171, the communication section 23 detects a frame transmitted by the base station AP1 in the first frequency band, that is, a frame transmitted in BSS1.

[0346] For example, when a frame transmitted in BSS1 is detected, the amplifier section 35 of the communication section 23 receives the frame through the antenna 24 and supplies the frame to the control section 22 via the set of sections from the radio interface section 34 to the data processing section 21. The control section 22 obtains information related to the communication in BSS1 (such as at least a part of the SR information) from the frame thus received.

[0347] In addition, the control section 22 obtains information related to the communication in BSS1 (such as the received power observed during the reception of the frame transmitted by the base station AP1) from the respective sections of the communication section 23.

[0348] In step S172, the control section 22 generates control information for BSS2 different from the detected communication in BSS1.

[0349] For example, the control section 22 generates control information based on the information related to the communication in BSS1 obtained in step S171 and the information obtained by performing calculations on the above information, and supplies the control information to the data processing section 21.

[0350] Once the control information is generated, the process in step S173 is executed to end the BSS communication control process. However, the process in step S173 is similar to Figure 10 the process in step S83 in

[0351] As described above, the wireless communication device 11 serving as the control base station detects a frame transmitted in the BSS, generates control information, and transmits a frame including the generated control information to a base station belonging to another BSS or from a terminal in the second frequency band. Therefore, the control information based on the information related to the communication in the predetermined BSS is used to control the communication in another BSS, and more efficient communication can be achieved.

[0352] It should be noted that in reference to Figure 13When the described BSS communication control process is executed, the base station AP2 in BSS2 also performs the BSS communication process on the control information receiving side with reference to Figure 12 the described control information.

[0353] <Example of the Structure of a Computer>

[0354] Incidentally, the steps of the above-described series of processes can be executed by hardware or by software. When the steps of the series of processes are executed by software, the program included in the software is installed in a computer. Here, the computer includes a computer integrated in dedicated hardware and, for example, a general-purpose personal computer that can execute various functions by using various programs installed in the computer.

[0355] Figure 14 is a block diagram showing an example of the hardware structure of a computer that executes the steps of the above-described series of processes based on a program.

[0356] In the computer, a CPU (Central Processing Unit) 501, a ROM (Read Only Memory) 502, and a RAM (Random Access Memory) 503 are connected together via a bus 504.

[0357] The bus 504 is also connected to an I / O (Input / Output) interface 505. The I / O interface 505 is connected to an input section 506, an output section 507, a recording section 508, a communication section 509, and a drive 510.

[0358] The input section 506 includes a keyboard, a mouse, a microphone, an image capturing element, etc. The output section 507 includes a display, a speaker, etc. The recording section 508 includes a hard disk or a non-volatile memory. The communication section 509 includes an antenna, a network interface, etc. The drive 510 drives a removable recording medium 511, such as a magnetic disk, an optical disk, a magneto-optical disk, or a semiconductor memory.

[0359] In the computer configured as described above, the steps of the above-described series of processes are executed by loading the program recorded in the recording section 508 into the RAM 503 via the CPU 501, for example, through the I / O interface 505 and the bus 504.

[0360] The program executed by the computer (CPU501) can be provided by being recorded, for example, in the removable recording medium 511 used as a packaging medium. In addition, the program can be provided via a wired or wireless transmission medium, such as a local area network, the Internet, or digital satellite broadcasting.

[0361] In this computer, by installing the removable recording medium 511 in the drive 510, the program can be installed in the recording section 508 via the I / O interface 505. Additionally, the program can be received by the communication section 509 via a wired or wireless transmission medium and installed in the recording section 508. Alternatively, the program can be pre-installed in the ROM 502 or the recording section 508.

[0362] It should be noted that the program executed by the computer can be a program that performs processing in chronological order or in parallel along the order described here, or at the necessary moment when the program is called.

[0363] Additionally, the embodiments of the present technology are not limited to the above embodiments, but various changes can be made to the embodiments without departing from the spirit of the present technology.

[0364] For example, the present technology can be configured as cloud computing, in which a function is shared among multiple devices via a network and jointly processed.

[0365] Additionally, the steps described in the above flowcharts can be executed not only by one device but also shared among multiple devices for execution.

[0366] Additionally, in the case where one step includes operations of multiple processes, the operations of the multiple processes included in the one step can be executed not only by one device but also shared among multiple devices for execution.

[0367] Additionally, the present technology can be constructed as follows.

[0368] (1) A wireless communication device for controlling a second network including a plurality of first networks,

[0369] Each first network includes an access point and one or more wireless communication terminals, and the wireless communication device includes:

[0370] A control section configured to generate control information for controlling communication in another first network based on communication information related to communication in a predetermined first network; and

[0371] A communication section configured to send a frame including the control information and an identifier indicating that the frame has been sent from the second network controlled by the wireless communication device.

[0372] (2) The wireless communication device according to (1), wherein the communication section receives a frame including communication information sent by one of the wireless communication terminals or the access point in the predetermined first network.

[0373] (3) The wireless communication device according to (1) or (2), wherein the communication information includes information for spatial recycling.

[0374] (4) The wireless communication device according to any one of (1) to (3), wherein the communication information includes at least one piece of information among a schedule, frequency resources, spatial resources, transmission power, modulation and coding scheme, allowable interference intensity, frame priority, buffer information about an access point or a wireless communication terminal, communication type, number of wireless communication terminals, or position of a wireless communication terminal in a first network.

[0375] (5) The wireless communication device according to any one of (1) to (4), wherein the communication section transmits a beacon frame of a second network including an identifier.

[0376] (6) The wireless communication device according to (5), wherein the beacon frame is transmitted at a frequency lower than the frequency at which the beacon frame of the first network is transmitted.

[0377] (7) The wireless communication device according to any one of (1) to (6), wherein the control section controls frame exchange for the configuration of the second network and connection to the second network with an access point.

[0378] (8) The wireless communication device according to (7), wherein the control section controls frame exchange with a wireless communication terminal.

[0379] (9) The wireless communication device according to (7), wherein the communication section receives a frame including information related to a wireless communication terminal controlled by an access point for establishing a connection with the wireless communication terminal, and the frame is transmitted from the access point.

[0380] (10) The wireless communication device according to any one of (1) to (9), wherein the communication section transmits a frame to one of the wireless communication terminals to invite connection to another access point different from the access point to which the wireless communication terminal is connected.

[0381] (11) The wireless communication device according to any one of (1) to (10), wherein the control section controls frame exchange with a wireless communication terminal not belonging to the first network, and the frame exchange is for the configuration of the second network and connection to the second network.

[0382] (12) The wireless communication device according to (11), wherein the communication section transmits a frame to a wireless communication terminal not belonging to the first network to invite connection to a predetermined access point.

[0383] (13) The wireless communication device according to any one of (1) to (12), wherein a frame transmitted in the second network includes an identifier indicating that the frame has been transmitted from the second network controlled by the wireless communication device.

[0384] (14) The wireless communication device as described in (13), wherein the identifier is included in the physical header of the frame.

[0385] (15) The wireless communication device as described in (13), wherein the value of the identifier varies with the second network.

[0386] (16) The wireless communication device as described in any one of (13) to (15), wherein the value of the identifier is the same as the value of the identifier of the first network to which the access point or the wireless communication terminal corresponding to the destination of the frame belongs.

[0387] (17) The wireless communication device as described in any one of (13) to (15), wherein the value of the identifier includes one of the values assigned to the first network and is not used in the first network.

[0388] (18) The wireless communication device as described in any one of (1) to (17), wherein communication in the second network is performed at a frequency different from the frequency used for communication in the first network.

[0389] (19) The wireless communication device as described in (18), wherein the frequency is lower than the frequency used for communication in the first network.

[0390] (20) The wireless communication device as described in any one of (1) to (19), wherein the control section controls the execution of an inspection sequence for inspecting the configuration of the second network, the transmission and reception of signals of the second network, and whether the operation of the second network is supported with respect to the access point or the wireless communication terminal.

[0391] (21) A wireless communication method, comprising:

[0392] A wireless communication device that controls a second network including a plurality of first networks,

[0393] generating control information for controlling communication in another first network based on communication information related to communication in a predetermined first network; and

[0394] transmitting a frame that includes the control information and an identifier indicating that the frame has been transmitted from the second network controlled by the wireless communication device,

[0395] wherein each first network includes an access point and one or more wireless communication terminals.

[0396] (22) A wireless communication device belonging to a first network, the first network including an access point and one or more wireless communication terminals, the wireless communication device including:

[0397] A control section configured to

[0398] Control the transmission of a frame to a master access point, the frame including communication information related to communication in a first network to which the wireless communication device belongs, the master access point controlling a second network including a plurality of first networks, or

[0399] Control communication in the first network based on control information included in a frame received from the master access point, the control information being generated based on communication information in another first network different from the first network to which the wireless communication device belongs.

[0400] (23) The wireless communication device according to (22), further comprising:

[0401] A communication part configured to transmit a frame including communication information related to communication in a first network to which the wireless communication device belongs.

[0402] (24) The wireless communication device according to (23), wherein the communication information includes information for spatial recycling.

[0403] (25) The wireless communication device according to (23) or (24), wherein the communication information includes at least one piece of information among a schedule, frequency resources, spatial resources, transmission power, modulation and coding scheme, allowable interference intensity, frame priority, buffer information about an access point or a wireless communication terminal, communication type, number of wireless communication terminals, or location of a wireless communication terminal in the first network.

[0404] (26) The wireless communication device according to any one of (23) to (25), wherein the communication part receives a beacon frame of a second network controlled by the master access point, the beacon frame including an identifier indicating that the beacon frame has been transmitted from the second network.

[0405] (27) The wireless communication device according to any one of (23) to (26), wherein the control part controls frame exchange for the construction of the second network and connection to the second network with the master access point.

[0406] (28) The wireless communication device according to (27), wherein the wireless communication device includes one of an access point or a wireless communication terminal.

[0407] (29) The wireless communication device according to (27), wherein the wireless communication device includes an access point, and

[0408] The communication part transmits a frame to the master access point for one of the wireless communication terminals controlled by the wireless communication device, the frame including information related to the wireless communication terminal for the establishment of a connection between the master access point and the wireless communication terminal.

[0409] (30) The wireless communication device as described in (29), wherein the communication section transmits a frame including information related to the main access point to a wireless communication terminal controlled by the wireless communication device.

[0410] (31) The wireless communication device as described in any one of (23) to (26), wherein the wireless communication device is one of the wireless communication terminals, and

[0411] the communication section receives a frame including information related to the main access point for establishing a connection with the main access point, and the frame has been transmitted from an access point of the first network to which the wireless communication device belongs.

[0412] (32) The wireless communication device as described in any one of (23) to (27), wherein the wireless communication device is one of the wireless communication terminals, and

[0413] in a case where the wireless communication device receives a frame that is an invitation to connect to another access point different from the access point of the first network to which the wireless communication device belongs and is transmitted from the main access point, the control section controls to connect to the another access point.

[0414] (33) The wireless communication device as described in any one of (22) to (30), wherein the control section controls the execution of a check sequence for checking the configuration of the second network, the transmission and reception of signals of the second network, and whether the operation of the second network is supported with respect to the main access point.

[0415] (34) The wireless communication device as described in any one of (22) to (33), wherein a frame transmitted in the second network includes an identifier indicating that the frame has been transmitted from the second network controlled by the main access point.

[0416] (35) The wireless communication device as described in any one of (22) to (34), wherein communication in the second network is performed at a frequency different from the frequency used for communication in the first network.

[0417] (36) The wireless communication device as described in (35), wherein the frequency is lower than the frequency used for communication in the first network.

[0418] (37) A wireless communication method, comprising:

[0419] by a wireless communication device belonging to a first network including an access point and one or more wireless communication terminals,

[0420] controlling the transmission of a frame to a main access point, the frame including communication information related to communication in the first network to which the wireless communication device belongs, and the main access point controls a second network including a plurality of first networks, or

[0421] Controlling communication in a first network based on control information included in a frame received from a master access point, the control information being generated based on communication information in another first network different from the first network to which the wireless communication device belongs.

[0422] List of labels

[0423] 11 Wireless communication device

[0424] 21 Data processing section

[0425] 22 Control section

[0426] 23 Communication section

[0427] 35-1 to 35-N, 35 Amplifier section

Claims

1. A communication control device configured to control a high-level network including a plurality of low-level networks, each low-level network including an access point and one or more wireless communication terminals, the communication control device including a processing circuit configured to: generate control information for controlling communication in a second low-level network among the plurality of low-level networks, the control information being related to communication in a first low-level network among the plurality of low-level networks; and control the transmission of a frame including the control information and an identifier indicating that the frame has been transmitted from the high-level network controlled by the communication control device, wherein the control information includes at least one piece of information indicating a schedule, frequency resources, spatial resources, transmission power, modulation and coding scheme, allowable interference intensity, frame priority, buffer status regarding a first access point or a first wireless communication terminal in the first low-level network, communication type, number of first wireless communication terminals in the first low-level network, or location of the first wireless communication terminal in the first low-level network, and wherein the control information enables a second access point in the second low-level network to determine a transmission power for communication in the second low-level network based on the control information.

2. The communication control device according to claim 1, wherein the communication control device constructs the first low-level network for the first access point.

3. The communication control device according to claim 1, wherein the processing circuit is configured to control the reception of a frame including communication information transmitted by one of the first wireless communication terminals or the first access point in the first low-level network, wherein the communication information includes at least one piece of information indicating a schedule, frequency resources, spatial resources, transmission power, modulation and coding scheme, allowable interference intensity, frame priority, buffer status regarding a first access point or a first wireless communication terminal in the first low-level network, communication type, number of first wireless communication terminals in the first low-level network, or location of the first wireless communication terminal in the first low-level network.

4. The communication control device according to claim 1, wherein the processing circuit is configured to control the transmission of a beacon frame of the high-level network including the identifier.

5. The communication control device according to claim 1, wherein the processing circuit is configured to control frame exchanges with each access point for the construction of the high-level network and connection to the high-level network.

6. The communication control device according to claim 1, wherein the processing circuit is configured to control the transmission of a frame inviting a wireless communication terminal to connect to another access point different from the access point to which the wireless communication terminal is connected.

7. The communication control device according to claim 1, wherein the processing circuit is configured to control frame exchanges with wireless communication terminals not belonging to the plurality of low-level networks, the frame exchanges being for the construction of the high-level network and connection to the high-level network.

8. The communication control device according to claim 1, wherein a frame transmitted in the high-level network includes an identifier indicating that the frame has been transmitted from the high-level network controlled by the communication control device.

9. The communication control device according to claim 8, wherein the identifier is included in a physical header of the frame.

10. The communication control device according to claim 1, wherein communication in the high-level network is performed at a frequency different from a frequency used for communication in the low-level network.

11. The communication control device according to claim 1, wherein the processing circuit is configured to control the execution of a check sequence for checking whether the high-level network structure, transmission and reception of signals in the high-level network, and operation of the high-level network are supported with respect to an access point or a wireless communication terminal.

12. A communication control method, comprising: by a communication control device configured to control a high-level network including a plurality of low-level networks, generating control information for controlling communication in a second low-level network among the plurality of low-level networks, the control information being related to communication in a first low-level network among the plurality of low-level networks; and controlling to send a frame that includes the control information and an identifier indicating that the frame has been sent from the high-level network controlled by the communication control device, wherein each low-level network includes an access point and one or more wireless communication terminals, wherein the control information includes at least one piece of information indicating a schedule, frequency resource, spatial resource, transmission power, modulation and coding scheme, allowable interference intensity, frame priority, buffer state regarding a first access point or a first wireless communication terminal in the first low-level network, communication type, number of first wireless communication terminals in the first low-level network, or location of the first wireless communication terminal in the first low-level network, and wherein the control information enables a second access point in the second low-level network to determine a transmission power for communication in the second low-level network based on the control information.

13. A communication control device for a wireless communication device belonging to a first low-level network, the first low-level network including an access point and one or more wireless communication terminals, the communication control device including a processing circuit configured to: control to send a frame including first communication information related to communication in the first low-level network to which the wireless communication device belongs to a master access point, the master access point controlling a high-level network including a plurality of low-level networks, or control communication in the first low-level network based on control information included in a frame received from the master access point, the control information being generated based on second communication information in a second low-level network different from the first low-level network to which the wireless communication device belongs, wherein each of the first communication information and the second communication information includes at least one piece of information indicating a schedule, frequency resource, spatial resource, transmission power, modulation and coding scheme, allowable interference intensity, frame priority, buffer state regarding an access point or a wireless communication terminal in the low-level network, communication type, number of wireless communication terminals in the low-level network, or location of the wireless communication terminal in the low-level network, wherein the control information enables an access point in the first low-level network to determine a transmission power for communication in the first low-level network based on the control information.

14. The communication control device according to claim 13, wherein the processing circuit is configured to control frame exchange with a primary access point for the construction of and connection to a high-level network.

15. The communication control device according to claim 13, wherein the wireless communication device is one of wireless communication terminals, and in a case where the processing circuit controls to receive a frame for inviting connection to another access point different from a first low-level network to which the wireless communication device belongs, sent from the primary access point, the processing circuit is configured to control connection to the another access point.

16. The communication control device according to claim 13, wherein the processing circuit is configured to control execution of a check sequence for checking the construction of a high-level network with the primary access point, transmission and reception of signals from and to the high-level network, and whether the operation of the high-level network is supported.

17. The communication control device according to claim 13, wherein a frame transmitted in the high-level network includes an identifier indicating that the frame has been transmitted from the high-level network controlled by the primary access point.

18. A communication control method, comprising: by a communication control device in a wireless communication device belonging to a first low-level network including an access point and one or more wireless communication terminals, controlling transmission of a frame to a primary access point, the frame including first communication information related to communication in the first low-level network to which the wireless communication device belongs, the primary access point controlling a high-level network including a plurality of low-level networks, or controlling communication in the first low-level network based on control information included in a frame received from the primary access point, the control information being generated based on second communication information in a second low-level network different from the first low-level network to which the wireless communication device belongs, wherein each of the first communication information and the second communication information includes at least one piece of information indicating a schedule, a frequency resource, a spatial resource, a transmission power, a modulation and coding scheme, an allowable interference intensity, a frame priority, a buffer state of an access point or a wireless communication terminal in the low-level network, a communication type, a number of wireless communication terminals in the low-level network, or a location of a wireless communication terminal in the low-level network, wherein the control information enables an access point in the first low-level network to determine a transmission power for communication in the first low-level network based on the control information.

19. A communication control device configured to control a high-level network including a plurality of low-level networks, each low-level network including an access point and one or more wireless communication terminals, the communication control device including a processing circuit configured to: generate control information for controlling communication in a second low-level network among the plurality of low-level networks, the control information being calculated based on communication information related to communication in a first low-level network among the plurality of low-level networks; and control transmission of a frame including the control information and an identifier indicating that the frame has been transmitted from the high-level network controlled by the communication control device, The communication information includes at least one piece of information among information indicating a schedule, frequency resources, spatial resources, transmission power, modulation and coding scheme, allowed interference intensity, frame priority, buffer status regarding a first access point or a first wireless communication terminal in a first low-level network, communication type, number of first wireless communication terminals in the first low-level network, or location of the first wireless communication terminals in the first low-level network, and the control information enables a second access point in the second low-level network to determine a transmission power for communication in the second low-level network based on the control information.

20. A communication control device in a wireless communication device belonging to a first low-level network, the first low-level network including an access point and one or more wireless communication terminals, the communication control device including a processing circuit configured to: control sending a frame to a master access point, the frame including first communication information related to communication in the first low-level network to which the wireless communication device belongs, the master access point controlling a high-level network including a plurality of low-level networks, or control communication in the first low-level network based on control information included in a frame received from the master access point, the control information being calculated based on second communication information in a second low-level network different from the first low-level network to which the wireless communication device belongs, wherein each of the first communication information and the second communication information includes at least one piece of information among information indicating a schedule, frequency resources, spatial resources, transmission power, modulation and coding scheme, allowed interference intensity, frame priority, buffer status regarding an access point or a wireless communication terminal in a low-level network, communication type, number of wireless communication terminals in the low-level network, or location of the wireless communication terminals in the low-level network, wherein the control information enables an access point in the first low-level network to determine a transmission power for communication in the first low-level network based on the control information.

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