Base station device and communication method

Abstract

To improve frequency utilization efficiency in a dense environment where a large number of wireless LAN devices exist in a frequency band in which a usable bandwidth is preset.SOLUTION: A first base station device includes a transmitting / receiving unit that transmits and receives radio signals, a resource allocation unit that determines an allocation of frequency resources to be used for communication with a first terminal device, and a control information generation unit that generates control information. When the first base station device communicates with the first terminal device using a first frequency channel and a second base station device is communicating with a second terminal device using a second frequency channel, the resource allocation unit allocates part of the second frequency channel to communication between the first base station device and the first terminal device, and the transmitting / receiving unit communicates with the first terminal device using the first frequency channel and the part of the second frequency channel.SELECTED DRAWING: Figure 10

Description

Technical Field

[0001] The present invention relates to a base station apparatus and a communication method.

Background Art

[0002] IEEE802.11ax, which realizes further high-speedization of IEEE802.11, a wireless LAN (Local Area Network) standard, is being standardized by IEEE (The Institute of Electrical and Electronics Engineers Inc.), and wireless LAN devices compliant with the specification draft have appeared on the market. Currently, as a successor standard to IEEE802.11ax, the standardization activity of IEEE802.11be has been started. With the rapid spread of wireless LAN devices, in the standardization of IEEE802.11be as well, consideration is being given to further improving the throughput per user in an overcrowded environment of wireless LAN devices.

[0003] In a wireless LAN, frame transmission can be performed using an unlicensed band in which wireless communication can be performed without permission (license) from a country or region. Currently, as unlicensed band ranges, in addition to the 2.4 GHz band and the 5 GHz band, the 6 GHz band and the 60 GHz band are mainly used. In order for a plurality of wireless LAN devices to share the unlicensed band, the available frequency band is divided into a predetermined bandwidth. For example, when two access points are adjacent to each other in a relatively close vicinity, the same frequency cannot be used simultaneously. However, when the unlicensed band is divided into a predetermined bandwidth in advance, each access point can communicate simultaneously by using different bands, although the frequency bandwidth that can be used at one time becomes smaller.

[0004] Therefore, in the IEEE 802.11 standardization, the unlicensed band is divided and managed into a bandwidth of 20 MHz (see Non-Patent Document 1). At this time, as described above, different wireless LAN devices can simultaneously use different bands. Also, when there are no other wireless LAN devices in communication near the wireless LAN device, the wireless LAN device can also expand the communication bandwidth and improve the communication speed by channel bonding that bundles and simultaneously uses the divided bands.

Prior Art Documents

Non-Patent Documents

[0005]

Non-Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, the fact that the bandwidth is fixed in advance means that the bandwidth available for the wireless LAN device is limited to an integer multiple of the bandwidth. Also, when a neighboring wireless LAN device secures a bandwidth of 20 MHz, other wireless LAN devices cannot use the 20 MHz bandwidth. This is the same even when the wireless LAN device securing the 20 MHz bandwidth actually uses only a part of the 20 MHz bandwidth, which limits the frequency utilization efficiency of the entire system.

[0007] The present invention has been made in view of the above problems, and its object is to disclose a base station device and a communication method that improve the frequency utilization efficiency in a terminal-dense environment where a large number of wireless LAN devices exist in a frequency band in which the available bandwidth is preset.

Means for Solving the Problems

[0008] The base station apparatus and communication method according to the present invention for solving the above-described problems are as follows.

[0009] (1) That is, an access point apparatus according to an aspect of the present invention is an access point apparatus for a wireless LAN, including a transmission unit and a reception unit. The transmission unit and the reception unit communicate with a station apparatus on a first channel, and the transmission unit transmits a trigger frame notifying permission regarding at least a part of a band of a second channel different from the first channel.

[0010] (2) Further, an access point apparatus according to an aspect of the present invention is as described in (1) above. After transmitting the trigger frame, the reception unit receives a response frame from the station apparatus, and the transmission unit and the reception unit communicate with the station apparatus using at least a part of the band of the second channel.

[0011] (3) Further, an access point apparatus according to an aspect of the present invention is as described in (1) above. Before transmitting the trigger frame, the reception unit performs carrier sense.

[0012] (4) Further, a station apparatus according to an aspect of the present invention is a station apparatus for a wireless LAN, including a transmission unit and a reception unit. The reception unit receives a trigger frame transmitted on a first channel from an access point apparatus, and the transmission unit transmits a response frame to the trigger frame. The trigger frame is a frame notifying permission regarding at least a part of a band of a second channel different from the first channel.

[0013] (5) Further, a station apparatus according to an aspect of the present invention is as described in (4) above. After the transmission unit transmits the response frame, the reception unit receives a wireless signal in at least a part of the band of the second channel.

[0014] (6) Also, a communication method according to an aspect of the present invention is a communication method of an access point device of a wireless LAN, wherein a computer communicates with a station device on a first channel, and includes a step of transmitting a trigger frame for notifying permission regarding at least a part of a band of a second channel different from the first channel.

[0015] (3) Also, a communication method according to an aspect of the present invention is a communication method of a station device of a wireless LAN, wherein a computer receives a trigger frame transmitted on a first channel from an access point device, and transmits a response frame for the trigger frame, and the trigger frame is a frame for notifying permission regarding at least a part of a band of a second channel different from the first channel.

Advantages of the Invention

[0016] According to the present invention, even in a terminal-dense environment where a plurality of wireless LAN devices are present in a frequency band with a preset available bandwidth, the frequency can be efficiently utilized, thus contributing to an improvement in the user throughput of the wireless LAN device.

Brief Description of the Drawings

[0017]

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Mode for Carrying Out the Invention

[0018] The communication system in this embodiment includes a wireless transmission device (access point device: Access point, base station device) and a plurality of wireless reception devices (station device: station, terminal device). Also, a network composed of a base station device and a terminal device is called a basic service set (BSS: Basic service set, management range). Further, the station device according to this embodiment can have the function of an access point device. Similarly, the access point device according to this embodiment can have the function of a station device. Therefore, hereinafter, when simply referred to as a communication device, the communication device can indicate both a station device and an access point device.

[0019] The base station device and the terminal device in the BSS shall perform communication based on CSMA / CA (Carrier Sense Multiple Access with Collision Avoidance), respectively. In this embodiment, the infrastructure mode in which the base station device communicates with a plurality of terminal devices is targeted. However, the method of this embodiment can also be implemented in the ad-hoc mode in which terminal devices directly communicate with each other. In the ad-hoc mode, the terminal device forms a BSS instead of the base station device. The BSS in the ad-hoc mode is also referred to as an IBSS (Independent Basic Service Set). Hereinafter, the terminal device that forms an IBSS in the ad-hoc mode can also be regarded as the base station device.

[0020] In the IEEE802.11 system, each device can transmit transmission frames of a plurality of frame types having a common frame format. The transmission frame is defined in the Physical (PHY) layer, the Medium Access Control (MAC) layer, and the Logical Link Control (LLC) layer, respectively.

[0021] The transmission frame of the PHY layer is called a Physical Protocol Data Unit (PPDU: PHY protocol data unit, physical layer frame). The PPDU is composed of a Physical layer header (PHY header) containing header information for signal processing in the physical layer and a Physical Service Data Unit (PSDU: PHY service data unit, MAC layer frame), which is a data unit processed in the physical layer. The PSDU can be composed of an Aggregated MPDU (A-MPDU) in which a plurality of MAC protocol data units (MPDUs: MAC protocol data units) that are retransmission units in the wireless section are aggregated.

[0022] The PPDU is modulated according to the corresponding standard. For example, in the case of the IEEE802.11n standard, it is modulated into an orthogonal frequency division multiplexing (OFDM) signal.

[0023] The PHY header includes reference signals such as a short training field (STF) used for signal detection and synchronization, a long training field (LTF) used to obtain channel information for data demodulation, etc., and control signals such as a signal (Signal: SIG) that includes control information for data demodulation. Also, the STF is classified into Legacy-STF (L-STF), High throughput-STF (HT-STF), Very high throughput-STF (VHT-STF), High efficiency-STF (HE-STF), Extremely high throughput-STF (EHT-STF), etc. according to the corresponding standard, and the LTF and SIG are similarly classified into L-LTF, HT-LTF, VHT-LTF, HE-LTF, L-SIG, HT-SIG, VHT-SIG, HE-SIG, EHT-SIG. The VHT-SIG is further classified into VHT-SIG-A1, VHT-SIG-A2, and VHT-SIG-B. Similarly, the HE-SIG is classified into HE-SIG-A1~4 and HE-SIG-B. Also, assuming technological updates in the same standard, a Universal SIGNAL (U-SIG) field containing additional control information can be included.

[0024] The SIG can include information such as modulation method and coding rate (MCS), spatial data multiplexing number (number of layers), number of spatial multiplex users, information indicating the presence or absence of space-time coding (e.g., information indicating the presence or absence of space-time coded transmission diversity), information indicating the destination of the frame, information associated with the frame length of the frame (TXOP, etc.) as information for demodulating the received frame.

[0025] Furthermore, the PHY header can include information for identifying the BSS of the transmission source of the transmission frame (hereinafter also referred to as BSS identification information). The information for identifying the BSS can be, for example, the SSID (Service Set Identifier) of the BSS or the MAC address of the base station device of the BSS. Also, the information for identifying the BSS can be a value unique to the BSS (such as BSS Color, etc.) other than the SSID and the MAC address.

[0026] Note that since the PHY header including the SIG contains information necessary for data demodulation, it is desirable to have resistance to transmission errors. Also, it is desirable that the PHY header be correctly received by wireless LAN devices other than the destination wireless LAN device. Considering that there may be wireless LAN devices with a poor communication environment, it is desirable to set a modulation method with high redundancy and a coding rate for the PHY header, particularly for the SIG. The communication device can set, for the PHY header, a modulation method with a small number of modulation levels such as BPSK modulation or a low coding rate.

[0027] The MPDU is composed of a MAC layer header (MAC header) including header information for performing signal processing at the MAC layer, a MAC service data unit (MSDU: MAC service data unit) or a frame body which is a data unit processed at the MAC layer, and a frame check sequence (FCS) for checking whether there is an error in the frame. Also, a plurality of MSDUs can be aggregated as an aggregated MSDU (A-MSDU).

[0028] The frame types of the MAC layer transmission frames are broadly classified into three types: management frames that manage connection states between devices, control frames that manage communication states between devices, and data frames that contain actual transmitted data. Each of these is further classified into multiple types of sub-frame types. Control frames include acknowledgment (Ack) frames, request to send (RTS) frames, clear to send (CTS) frames, etc. Management frames include beacon frames, probe request frames, probe response frames, authentication frames, association request frames, association response frames, etc. Data frames include data frames, CF-poll frames, etc. Each device can grasp the frame type and sub-frame type of the received frame by reading the content of the frame control field included in the MAC header.

[0029] Note that Ack may include Block Ack. Block Ack can perform acknowledgment of reception completion for multiple MPDUs.

[0030] The beacon frame includes fields for describing the period (Beacon interval) at which the beacon is transmitted and the SSID. The base station device can periodically notify the BSS of the beacon frame, and the terminal device can grasp the base station devices around the terminal device by receiving the beacon frame. The process by which the terminal device grasps the base station device based on the beacon frame notified by the base station device is called passive scanning. On the other hand, the process by which the terminal device explores the base station device by notifying the BSS of a probe request frame is called active scanning. The base station device can transmit a probe response frame as a response to the probe request frame, and the content described in the probe response frame is equivalent to that of the beacon frame.

[0031] After the terminal device recognizes the base station device, it performs connection processing on the base station device. The connection processing is classified into an authentication procedure and an association procedure. The terminal device transmits an authentication frame (authentication request) to the base station device to which it wishes to connect. When the base station device receives the authentication frame, it transmits an authentication frame (authentication response) containing a status code indicating the approval or disapproval of authentication for the terminal device to the terminal device. The terminal device can determine whether it has been permitted to authenticate with the base station device by reading the status code described in the authentication frame. Note that the base station device and the terminal device can exchange authentication frames multiple times.

[0032] After the authentication procedure, the terminal device transmits a connection request frame to perform a connection procedure with the base station device. When the base station device receives the connection request frame, it determines whether to permit the connection of the terminal device and transmits a connection response frame to notify the result. In addition to the status code indicating the availability of the connection process, the connection response frame contains an association identifier (AID) for identifying the terminal device. By setting different AIDs for the terminal devices that have been granted connection permission, the base station device can manage multiple terminal devices.

[0033] After the connection process is performed, the base station device and the terminal device perform actual data transmission. In the IEEE802.11 system, a distributed control mechanism (DCF), a centralized control mechanism (PCF), and extended mechanisms thereof (such as enhanced distributed channel access (EDCA) and hybrid coordination function (HCF)) are defined. Hereinafter, the case where the base station device transmits a signal to the terminal device by DCF will be described as an example.

[0034] In DCF, before communication, the base station device and the terminal device perform carrier sense (CS) to check the usage status of the radio channel around their own devices. For example, when the base station device, which is the transmitting station, receives a signal higher than a predetermined clear channel assessment level (CCA level) on the radio channel, it delays the transmission of the transmission frame on the radio channel. Hereinafter, in the radio channel, the state in which a signal equal to or higher than the CCA level is detected is called the busy state, and the state in which a signal equal to or higher than the CCA level is not detected is called the idle state. In this way, the CS performed based on the power of the signal actually received by each device (received power level) is called physical carrier sense (physical CS). Note that the CCA level is also called the carrier sense level (CS level) or the CCA threshold (CCAT). Note that when the base station device and the terminal device detect a signal equal to or higher than the CCA level, they enter at least the operation of demodulating the signal in the PHY layer.

[0035] Note that hereinafter, when simply described as carrier sense, it includes the case of performing virtual carrier sense described later. Also, hereinafter, when simply described as the carrier sense level, it also includes the case of indicating the minimum reception sensitivity indicating the reception signal power for which the communication device demodulates at least the signal in the PHY layer. That is, when the communication device receives a frame and observes that the reception signal power of the frame is equal to or higher than the minimum reception sensitivity, it is necessary to demodulate at least the signal in the PHY layer for the frame. This means that when the communication device observes a reception signal power equal to or lower than the minimum reception sensitivity, it is not necessary to demodulate the frame, and the communication device can attempt to transmit the frame. Therefore, it can be said that the carrier sense level and the minimum reception sensitivity have the same meaning.

[0036] The base station device performs carrier sensing for a period of inter-frame space (IFS) corresponding to the type of transmission frame to be transmitted, and determines whether the radio channel is in a busy state or an idle state. The period during which the base station device performs carrier sensing varies depending on the frame type and sub-frame type of the transmission frame that the base station device will transmit next. In the IEEE802.11 system, a plurality of IFSs with different periods are defined, such as the Short IFS (SIFS) used for the transmission frame with the highest priority, the Polling IFS (PIFS) used for the transmission frame with a relatively high priority, and the Distributed Coordination Function IFS (DIFS) used for the transmission frame with the lowest priority. When the base station device transmits a data frame using DCF, the base station device uses DIFS.

[0037] After waiting for only the DIFS, the base station device waits for an additional random back-off time to prevent frame collisions. In the IEEE802.11 system, a random back-off time called the contention window (CW) is used. In CSMA / CA, it is assumed that the transmission frame transmitted by a certain transmitting station is received by the receiving station without interference from other transmitting stations. Therefore, if transmitting stations transmit transmission frames at the same timing, the frames will collide and the receiving station will not be able to receive them correctly. Therefore, before starting transmission, each transmitting station waits for a randomly set time to avoid frame collisions. When the base station device determines that the radio channel is in an idle state through carrier sensing, it starts counting down the CW. Only when the CW becomes 0 can the base station device acquire the right to transmit and transmit the transmission frame to the terminal device. If the base station device determines that the radio channel is in a busy state through carrier sensing during the countdown of the CW, the countdown of the CW is stopped. Then, when the radio channel becomes idle, following the previous IFS, the base station device resumes the countdown of the remaining CW.

[0038] The terminal device, which is a receiving station, receives a transmission frame, reads the PHY header of the transmission frame, and demodulates the received transmission frame. Then, the terminal device can recognize whether the transmission frame is addressed to itself by reading the MAC header of the demodulated signal. Note that the terminal device can also determine the destination of the transmission frame based on the information described in the PHY header (for example, the group identifier (GID: Group identifier, Group ID) described in VHT-SIG-A).

[0039] When the terminal device determines that the received transmission frame is addressed to itself and can demodulate the transmission frame without error, it must transmit an ACK frame indicating that the frame has been correctly received to the base station device, which is the transmitting station. The ACK frame is one of the highest-priority transmission frames that is transmitted only after waiting for the SIFS period (no random backoff time is taken). The base station device ends a series of communications upon receiving the ACK frame transmitted from the terminal device. Note that when the terminal device cannot correctly receive the frame, the terminal device does not transmit an ACK. Therefore, when the base station device does not receive an ACK frame from the receiving station within a certain period (SIFS + ACK frame length) after transmitting the frame, the communication is considered to have failed and the communication is ended. Thus, the end of a single communication (also called a burst) in the IEEE802.11 system is determined by the presence or absence of an ACK frame reception, except for special cases such as the transmission of a notification signal such as a beacon frame or when fragmentation used to divide transmission data is employed.

[0040] When the terminal device determines that the received transmission frame is not addressed to itself, it sets a Network Allocation Vector (NAV) based on the length (Length) of the transmission frame described in the PHY header or the like. The terminal device does not attempt communication during the period set in the NAV. That is, since the terminal device performs the same operation during the period set in the NAV as when it determines that the radio channel is busy by physical CS, the communication control by the NAV is also called virtual carrier sense (virtual CS). The NAV is set not only based on the information described in the PHY header but also by a Request to Send (RTS) frame or a Clear to Send (CTS) frame introduced to solve the hidden terminal problem.

[0041] For DCF where each device performs carrier sense and autonomously acquires the right to transmit, in PCF, a control station called a Point Coordinator (PC) controls the transmission rights of each device within the BSS. Generally, the base station device becomes the PC and acquires the transmission rights of the terminal devices within the BSS.

[0042] During the communication period by PCF, it includes a contention-free period (CFP) and a contention period (CP). During the CP, communication is performed based on the DCF described above, and the PC controls the transmission right during the CFP. The base station device, which is a PC, notifies the BSS of a beacon frame describing the CFP period (CFP Max duration) etc. prior to the PCF communication. Note that PIFS is used for the transmission of the beacon frame notified at the start of PCF transmission, and it is transmitted without waiting for the CW. The terminal device that receives the beacon frame sets the CFP period described in the beacon frame in the NAV. Thereafter, until the NAV elapses or a signal notifying the end of the CFP in the BSS (for example, a data frame including CF-end) is received, the terminal device can acquire the transmission right only when it receives a signal (for example, a data frame including CF-poll) that signals the acquisition of the transmission right transmitted from the PC. Note that within the CFP period, packet collisions do not occur within the same BSS, so each terminal device does not take the random backoff time used in DCF.

[0043] The wireless medium can be divided into a plurality of resource units (RUs). FIG. 4 is a schematic diagram showing an example of the divided state of the wireless medium. For example, in resource division example 1, the wireless communication device can divide the frequency resource (sub-carrier, frequency tone, tone), which is the wireless medium, into 9 RUs. Similarly, in resource division example 2, the wireless communication device can divide the frequency resource, which is the wireless medium, into 5 RUs. Of course, the resource division example shown in FIG. 4 is just one example. For example, the plurality of RUs can also be configured with different numbers of sub-carriers respectively. In addition, the wireless medium divided as an RU can include not only frequency resources but also spatial resources. The wireless communication device (e.g., AP) can transmit frames to a plurality of terminal devices (e.g., a plurality of STAs) simultaneously by arranging frames addressed to different terminal devices in each RU. The AP can describe information indicating the divided state of the wireless medium (Resource allocation information) in the PHY header of the frame transmitted by itself as common control information. Furthermore, the AP can describe information indicating the RU in which the frame addressed to each STA is arranged (resource unit assignment information) in the PHY header of the frame transmitted by itself as specific control information.

[0044] Also, a plurality of terminal devices (e.g., a plurality of STAs) can transmit frames simultaneously by arranging and transmitting frames in the assigned RUs respectively. After receiving a frame (Trigger frame: TF) including trigger information transmitted from the AP, the plurality of STAs can wait for a predetermined period and then transmit frames. Each STA can identify the RU assigned to itself based on the information described in the TF. In addition, each STA can acquire an RU through random access based on the TF.

[0045] The AP can simultaneously allocate multiple RUs to a single STA. The multiple RUs can be composed of consecutive subcarriers or non-consecutive subcarriers. The AP can use the multiple RUs allocated to a single STA to transmit one frame, or can allocate and transmit multiple frames to different RUs respectively. At least one of the multiple frames can be a frame containing common control information for multiple terminal devices that are destinations of Resource allocation information.

[0046] A single STA can be allocated multiple RUs by the AP. The STA can use the multiple allocated RUs to transmit one frame. Also, the STA can use the multiple allocated RUs to allocate and transmit multiple frames to different RUs respectively. The multiple frames can be frames of different frame types.

[0047] The AP can allocate multiple AIDs (Association IDs) to a single STA. For the multiple AIDs allocated to a single STA, the AP can allocate RUs respectively. For the multiple AIDs allocated to a single STA, the AP can use the respectively allocated RUs to transmit different frames respectively. The different frames can be frames of different frame types.

[0048] One STA can be assigned multiple AIDs (Associate IDs) by an AP. One STA can be assigned an RU for each of the assigned multiple AIDs. One STA recognizes all the RUs assigned to each of the multiple AIDs assigned to the self-device as the RUs assigned to the self-device, and can transmit one frame using the assigned multiple RUs. Also, one STA can transmit multiple frames using the assigned multiple RUs. At this time, information indicating the AID associated with the RU assigned to each of the multiple frames can be described and transmitted. One STA can transmit different frames using the RUs assigned to each of the assigned multiple AIDs. The different frames can be frames of different frame types.

[0049] Hereinafter, the base station device and the terminal device are collectively referred to as a wireless communication device or a communication device. Also, the information exchanged when a certain wireless communication device communicates with another wireless communication device is also referred to as data. That is, the wireless communication device includes a base station device and a terminal device.

[0050] The wireless communication device has either or both of the functions of transmitting and receiving a PPDU. FIG. 1 is a diagram showing an example of the PPDU configuration transmitted by the wireless communication device. The PPDU corresponding to the IEEE802.11a / b / g standard has a configuration including L-STF, L-LTF, L-SIG, and a Data frame (MAC Frame, MAC frame, payload, data section, data, information bits, etc.). The PPDU corresponding to the IEEE802.11n standard has a configuration including L-STF, L-LTF, L-SIG, HT-SIG, HT-STF, HT-LTF, and a Data frame. The PPDU corresponding to the IEEE802.11ac standard has a configuration including L-STF, L-LTF, L-SIG, VHT-SIG-A, VHT-STF, VHT-LTF, VHT-SIG-B, and part or all of the Data frame. The PPDU being considered in the IEEE802.11ax standard has a configuration including L-STF, L-LTF, L-SIG, RL-SIG in which L-SIG is repeated temporally, HESIG-A, HE-STF, HE-LTF, HE-SIG-B, and part or all of the Data frame. The PPDU being considered in the IEEE802.11be standard has a configuration including L-STF, L-LTF, L-SIG, RL-SIG, U-SIG, EHTSIG, EHT-STF, EHT-LTF, and part or all of the Data frame.

[0051] L-STF, L-LTF, and L-SIG surrounded by a dotted line in FIG. 1 are configurations commonly used in the IEEE802.11 standard (hereinafter, L-STF, L-LTF, and L-SIG are also collectively referred to as an L-header). For example, a wireless communication device corresponding to the IEEE 802.11a / b / g standard can appropriately receive the L-header in a PPDU corresponding to the IEEE802.11n / ac standard. A wireless communication device corresponding to the IEEE 802.11a / b / g standard can receive a PPDU corresponding to the IEEE802.11n / ac standard by regarding it as a PPDU corresponding to the IEEE 802.11a / b / g standard.

[0052] However, since a wireless communication device compliant with the IEEE 802.11a / b / g standard cannot demodulate a PPDU compliant with the IEEE 802.11n / ac standard following the L-header, it cannot demodulate information regarding the Duration / ID field used for setting the transmission address (TA: Transmitter Address), the reception address (RA: Receiver Address), or the NAV.

[0053] As a method for a wireless communication device compliant with the IEEE 802.11a / b / g standard to appropriately set the NAV (or perform a reception operation for a predetermined period), IEEE 802.11 stipulates a method of inserting Duration information into the L-SIG. Information regarding the transmission rate within the L-SIG (RATE field, L-RATE field, L-RATE, L_DATARATE, L_DATARATE field) and information regarding the transmission period (LENGTH field, L-LENGTH field, L-LENGTH) are used for a wireless communication device compliant with the IEEE 802.11a / b / g standard to appropriately set the NAV.

[0054] FIG. 2 is a diagram showing an example of a method for inserting Duration information into an L-SIG. In FIG. 2, as an example, a PPDU configuration corresponding to the IEEE802.11ac standard is shown, but the PPDU configuration is not limited thereto. A PPDU configuration corresponding to the IEEE802.11n standard and a PPDU configuration corresponding to the IEEE802.11ax standard may also be used. TXTIME includes information regarding the length of the PPDU, aPreambleLength includes information regarding the length of the preamble (L-STF+L-LTF), and aPLCPHeaderLength includes information regarding the length of the PLCP header (L-SIG). L_LENGTH is a virtual period set for compatibility with the IEEE802.11 standard, Nops related to L_RATE, aSymbolLength which is information regarding the period of 1 symbol (symbol, OFDM symbol, etc.), aPLCPServiceLength indicating the number of bits included in the PLCP Service field, and is calculated based on aPLCPConvolutionalTailLength indicating the number of tail bits of the convolutional code. The wireless communication device can calculate L_LENGTH and insert it into the L-SIG. Further, the wireless communication device can calculate the L-SIG Duration. The L-SIG Duration indicates information regarding the period obtained by summing the period of the PPDU including L_LENGTH and the periods of the Ack and SIFS expected to be transmitted from the destination wireless communication device as a response thereto.

[0055] FIG. 3 is a diagram showing an example of L-SIG Duration in L-SIG TXOP Protection. DATA (frame, payload, data, etc.) is composed of part or both of the MAC frame and the PLCP header. Also, BA is Block Ack or Ack. The PPDU can include the L-STF, L-LTF, L-SIG, and can further be composed of one or more of DATA, BA, RTS, or CTS. In the example shown in FIG. 3, L-SIG TXOP Protection using RTS / CTS is shown, but CTS-to-Self can also be used. Here, the MAC Duration is the period indicated by the value of the Duration / ID field. Also, the Initiator can send a CF_End frame to notify the end of the L-SIG TXOP Protection period.

[0056] Next, a method for the wireless communication device to identify the BSS from the received frame will be described. In order for the wireless communication device to identify the BSS from the received frame, it is preferable that the wireless communication device transmitting the PPDU inserts information for identifying the BSS (BSS color, BSS identification information, a value unique to the BSS) into the PPDU. The information indicating the BSS color can be described in the HE-SIG-A.

[0057] The wireless communication device can transmit the L-SIG multiple times (L-SIG Repetition). For example, the receiving wireless communication device receives the L-SIG transmitted multiple times using MRC (Maximum Ratio Combining), thereby improving the demodulation accuracy of the L-SIG. Further, when the wireless communication device correctly receives and completes the L-SIG by MRC, it can interpret that the PPDU including the L-SIG is a PPDU compliant with the IEEE802.11ax standard.

[0058] During the reception operation of a PPDU, the wireless communication device can perform the reception operation of a part of another PPDU other than the PPDU (for example, a preamble, L-STF, L-LTF, PLCP header, etc. defined by IEEE802.11) (also referred to as a dual reception operation). When the wireless communication device detects a part of another PPDU other than the PPDU during the reception operation of the PPDU, it can update part or all of the destination address, source address, information related to the PPDU or the DATA period.

[0059] Ack and BA can also be referred to as responses (response frames). Also, probe responses, authentication responses, and connection responses can be referred to as responses. [1. First Embodiment]

[0060] FIG. 5 is a diagram showing an example of a wireless communication system according to the present embodiment. The wireless communication system 3-1 includes a wireless communication device 1-1 and wireless communication devices 2-1 to 4. Note that the wireless communication device 1-1 is also referred to as a base station device 1-1, and the wireless communication devices 2-1 to 4 are also referred to as terminal devices 2-1 to 4. Further, the wireless communication devices 2-1 to 4 and the terminal devices 2-1 to 4 are also referred to as wireless communication devices 2A and terminal devices 2A as devices connected to the wireless communication device 1-1. The wireless communication device 1-1 and the wireless communication device 2A are wirelessly connected and are in a state where they can transmit and receive PPDUs to and from each other. In addition, the wireless communication system according to the present embodiment includes a wireless communication system 3-2 in addition to the wireless communication system 3-1. The wireless communication system 3-2 includes a wireless communication device 1-2 and wireless communication devices 2-5 to 8. Note that the wireless communication device 1-2 is also referred to as a base station device 1-2, and the wireless communication devices 2-5 to 8 are also referred to as terminal devices 2-5 to 8. Further, the wireless communication devices 2-5 to 8 and the terminal devices 2-5 to 8 are also referred to as wireless communication devices 2B and terminal devices 2B as devices connected to the wireless communication device 1-2. The wireless communication system 3-1 and the wireless communication system 3-2 form different BSSs, but this does not necessarily mean that the ESSs (Extended Service Sets) are different. The ESS indicates a service set that forms a LAN (Local Area Network). That is, wireless communication devices belonging to the same ESS can be regarded as belonging to the same network from the upper layer. Note that the wireless communication systems 3-1 and 3-2 can further include a plurality of wireless communication devices.

[0061] FIG. 6 is a diagram showing an example of the device configuration of wireless communication devices 1-1, 1-2, 2A, and 2B (hereinafter, also collectively referred to as wireless communication device 10-1 or station device 10-1 or simply station device). The wireless communication device 10-1 includes an upper layer part (upper layer processing step) 10001-1, an autonomous distributed control part (autonomous distributed control step) 10002-1, a transmission part (transmission step) 10003-1, a reception part (reception step) 10004-1, and an antenna part 10005-1. Also, the transmission part (transmission step) 10003-1 and the reception part (reception step) 10004-1 are collectively referred to as a transceiver part (transceiver step).

[0062] The upper layer part 10001-1 is connected to other networks and can notify the autonomous distributed control part 10002-1 of information related to traffic. The information related to traffic may be, for example, information addressed to other wireless communication devices, or control information included in management frames or control frames.

[0063] FIG. 7 is a diagram showing an example of the device configuration of the autonomous distributed control part 10002-1. The autonomous distributed control part 10002-1 includes a CCA part (CCA step) 10002a-1, a backoff part (backoff step) 10002b-1, and a transmission determination part (transmission determination step) 10002c-1.

[0064] The CCA part 10002a-1 can perform a state determination of the wireless resource (including a determination of busy or idle) using either one or both of information related to the received signal power received via the wireless resource and information related to the received signal (including the information after decoding) notified from the reception part. The CCA part 10002a-1 can notify the backoff part 10002b-1 and the transmission determination part 10002c-1 of the state determination information of the wireless resource.

[0065] The back-off unit 10002b-1 can perform back-off using the radio resource status determination information. The back-off unit 10002b-1 generates a CW and has a countdown function. For example, when the radio resource status determination information indicates "idle", the back-off unit 10002b-1 can execute the countdown of the CW, and when the radio resource status determination information indicates "busy", the back-off unit 10002b-1 can stop the countdown of the CW. The back-off unit 10002b-1 can notify the transmission determination unit 10002c-1 of the value of the CW.

[0066] The transmission determination unit 10002c-1 makes a transmission determination using either one or both of the radio resource status determination information and the value of the CW. For example, when the radio resource status determination information indicates "idle" and the value of the CW is 0, the transmission determination unit 10002c-1 can notify the transmission unit 10003-1 of the transmission determination information. Also, when the radio resource status determination information indicates "idle", the transmission determination unit 10002c-1 can notify the transmission unit 10003-1 of the transmission determination information.

[0067] The transmission unit 10003-1 includes a physical layer frame generation unit (physical layer frame generation step) 10003a-1 and a radio transmission unit (radio transmission step) 10003b-1. The physical layer frame generation unit 10003a-1 has a function of generating a physical layer frame (PPDU) based on the transmission determination information notified from the transmission determination unit 10002c-1. The physical layer frame generation unit 10003a-1 performs error correction coding, modulation, pre-coding filter multiplication, etc. on the transmission frame sent from the upper layer. The physical layer frame generation unit 10003a-1 notifies the generated physical layer frame to the radio transmission unit 10003b-1.

[0068] The frame generated by the physical layer frame generation unit 10003a-1 includes control information. The control information includes information indicating in which RU (where RU includes both frequency resources and spatial resources) the data addressed to each wireless communication device is arranged. Further, the frame generated by the physical layer frame generation unit 10003a-1 includes a trigger frame for instructing the wireless communication device, which is the destination terminal, to transmit the frame. The trigger frame includes information indicating the RU to be used by the wireless communication device instructed to transmit the frame when transmitting the frame.

[0069] The wireless transmission unit 10003b-1 converts the physical layer frame generated by the physical layer frame generation unit 10003a-1 into a signal in the radio frequency (RF) band to generate a radio frequency signal. The processes performed by the wireless transmission unit 10003b-1 include digital-to-analog conversion, filtering, frequency conversion from the baseband band to the RF band, and the like.

[0070] The receiving unit 10004-1 has a configuration including a wireless receiving unit (wireless receiving step) 10004a-1 and a signal demodulating unit (signal demodulating step) 10004b-1. The receiving unit 10004-1 generates information regarding the received signal power from the RF band signal received by the antenna unit 10005-1. The receiving unit 10004-1 can notify the CCA unit 10002a-1 of the information regarding the received signal power and the information regarding the received signal.

[0071] The wireless receiving unit 10004a-1 has a function of converting the RF band signal received by the antenna unit 10005-1 into a baseband signal to generate a physical layer signal (for example, a physical layer frame). The processes performed by the wireless receiving unit 10004a-1 include frequency conversion processing from the RF band to the baseband band, filtering, and analog-to-digital conversion.

[0072] The signal demodulation unit 10004b-1 has a function of demodulating the physical layer signal generated by the wireless reception unit 10004a-1. The processes performed by the signal demodulation unit 10004b-1 include channel equalization, demapping, error correction decoding, etc. The signal demodulation unit 10004b-1 can extract, for example, the information included in the physical layer header, the information included in the MAC header, and the information included in the transmission frame from the physical layer signal. The signal demodulation unit 10004b-1 can notify the extracted information to the upper layer unit 10001-1. Note that the signal demodulation unit 10004b-1 can extract any one or all of the information included in the physical layer header, the information included in the MAC header, and the information included in the transmission frame.

[0073] The antenna unit 10005-1 has a function of transmitting the radio frequency signal generated by the wireless transmission unit 10003b-1 into the wireless space toward another wireless communication device 10-1. The antenna unit 10005-1 also has a function of receiving the radio frequency signal transmitted from another wireless communication device 10-1.

[0074] The wireless communication device 10-1 can cause the wireless communication devices around the own device to set the NAV for only that period by describing, in the PHY header and MAC header of the frame to be transmitted, information indicating the period during which the own device uses the wireless medium. For example, the wireless communication device 10-1 can describe the information indicating that period in the Duration / ID field or the Length field of the frame to be transmitted. The NAV period set for the wireless communication devices around the own device will be referred to as the TXOP period (or simply TXOP) acquired by the wireless communication device 10-1. And the wireless communication device 10-1 that has acquired the TXOP will be called the TXOP acquirer (TXOP holder, TXOP holder). The frame type of the frame transmitted by the wireless communication device 10-1 to acquire the TXOP is not limited to anything, and it may be a control frame (for example, an RTS frame or a CTS-to-self frame), or a data frame.

[0075] The wireless communication device 10-1, which is a TXOP holder, can transmit a frame to a wireless communication device other than itself during the TXOP. When the wireless communication device 1-1 is a TXOP holder, within the period of the TXOP, the wireless communication device 1-1 can transmit a frame to the wireless communication device 2A. Also, within the TXOP period, the wireless communication device 1-1 can instruct the wireless communication device 2A to transmit a frame addressed to the wireless communication device 1-1. The wireless communication device 1-1 can transmit a trigger frame including information for instructing the wireless communication device 2A to transmit a frame addressed to the wireless communication device 1-1 within the TXOP period.

[0076] The wireless communication device 1-1 may secure a TXOP for all communication bands (e.g., Operation bandwidth) where frame transmission may occur, or may secure it for a specific communication band (Band) such as the communication band (e.g., Transmission bandwidth) where frames are actually transmitted.

[0077] The wireless communication device that gives an instruction for frame transmission within the period of the acquired TXOP is not necessarily limited to a wireless communication device connected to itself. For example, in order to cause a wireless communication device not connected to itself to transmit a management frame such as a Reassociation frame or a control frame such as an RTS / CTS frame to a wireless communication device around itself, the wireless communication device can instruct the wireless communication device not connected to itself to transmit a frame.

[0078] In this embodiment, the signal demodulation unit of the station device can perform decoding processing and error detection on the received signal at the physical layer. Here, the decoding processing includes decoding processing for the error correction code applied to the received signal. Here, the error detection includes error detection using an error detection code (e.g., cyclic redundancy check (CRC) code) pre-assigned to the received signal, and error detection by an error correction code (e.g., low-density parity-check code (LDPC)) originally having an error detection function. The decoding processing at the physical layer can be applied for each coding block.

[0079] The upper layer transfers the decoding result of the physical layer in the signal demodulation unit to the MAC layer. In the MAC layer, the MAC layer signal is restored from the transferred decoding result of the physical layer. Then, in the MAC layer, error detection is performed to determine whether the MAC layer signal transmitted by the station device that is the source of the received frame has been correctly restored.

[0080] The communication device according to this embodiment can divide the available frequency band into frequency channels or channels each having a predetermined bandwidth (Channel spacing). FIG. 9 is a schematic diagram showing an example of the frequency channel according to this embodiment. As shown in FIG. 9, the communication device according to this embodiment can divide the available frequency band into channels 901 each having a bandwidth of 20 MHz. Further, the communication device according to this embodiment can bundle a plurality of available frequency bands and use them as a channel 902 having a bandwidth of, for example, 40 MHz. Similarly, even wider channels such as channel 903 and channel 904 can be used. Note that the method of dividing the frequency band is not limited to the example shown in FIG. 9. The frequency band can also be divided based on a bandwidth smaller than 20 MHz. Also, another channel can be set between the divided channels. The channel can also be set as a guard band between channels.

[0081] FIG. 10 is a schematic diagram showing an example of communication according to this embodiment. The communication device according to this embodiment can communicate with other communication devices using frequency channels. In the following, as shown in FIG. 10, an example will be described in which the access point device 1-1 communicates with the station device 2-1 using channel 1001, and the access point device 1-2 communicates with the station device 2-5 using channel 1002. In the following, for simplicity, it is assumed that both channel 1001 and channel 1002 have a bandwidth of 20 MHz and are adjacent to each other, but it goes without saying that the method according to this embodiment is not limited to this example.

[0082] Under predetermined conditions, in addition to channel 1001, the access point device 1-1 can transmit a frame to the station device 2-1 using a part of the bandwidth of channel 1002. That is, under predetermined conditions, the access point device 1-1 according to this embodiment can transmit a frame to the station device 2-1 by regarding channel 1003 as an available frequency channel.

[0083] The frame transmitted by the access point device 1-1 using channel 1003 can include information indicating that channel 1003 is being used. This information can be, for example, information indicating the bandwidth occupied by the frame. When the frame transmitted via channel 1003 is a frame that causes a response frame, for example, when the station device 2-1 that received the frame returns a response frame, the response frame can be transmitted using channel 1003. Also, the station device 2-1 can transmit the response frame using channel 1001.

[0084] Here, the predetermined conditions are not limited to anything. For example, it is conceivable that the access point device 1-2 using channel 1002 permits the access point device 1-1 to use at least a part of the bandwidth of channel 1002. In this case, after the access point device 1-2 secures channel 1002 by carrier sense, it can transmit a first frame including information indicating permission to use channel 1002 to the access point device 1-1. Similarly, it is also possible for the station device 2-5 using channel 1002 to permit the access point device 1-1 to use at least a part of the bandwidth of channel 1002. In this case, the station device 2-5 can secure channel 1002. Note that the access point device 1-2 can transmit the first frame using channel 1002. That is, when the access point device 1-1 according to the present embodiment contemplates using a channel other than channel 1001, for example, in channel 1002, it needs to be in a state where frame decoding processing can be performed, that is, in a reception state.

[0085] Note that when the access point device 1-1 performs frame transmission using channel 1003, the restrictions on radio parameters such as the maximum transmission power allowed may be different between channel 1001 and channel 1002 that constitute channel 1003. At this time, the access point device 1-1 can perform frame transmission under the restrictions on the radio parameters imposed on all the channels constituting channel 1003. Also, the access point device 1-1 can perform frame transmission under the restrictions on the radio parameters imposed on the channel having the lowest center frequency among the channels constituting channel 1003 (channel 1001 in the case of FIG. 10 as an example).

[0086] Note that when the access point device 1-2 permits the use of the secured channel 1002 by the access point device 1-1, it cannot transmit frames on the channel 1002. Also, under predetermined conditions, the access point device 1-2 can transmit frames to communication devices other than the access point device 1-1 (e.g., the station device 2-5) using at least a part of the frequency band of the channel 1002 after permitting the use of the channel 1002 by the access point device 1-1. Here, as the predetermined conditions, a method using the allowable interference power of the station device 2-5 as a threshold value can be considered.

[0087] The access point device 1-1 that has received the first frame can use the channel 1002. At this time, the access point device 1-1 can transmit a response frame corresponding to the first frame to the access point device 1-2. The response frame can include information indicating the time period (time interval) or frequency band, or both, for using the channel 1002.

[0088] The first frame including information indicating permission to use the channel 1002 transmitted by the access point device 1-2 can include information indicating the time period (time interval) for permitting the access point device 1-1 to use the channel 1002. The frame can include information indicating the frequency band for permitting the access point device 1-1 to use the channel 1002.

[0089] The access point device 1-1 according to this embodiment can request permission to use channel 1002 from the access point device 1-2. In this case, the access point device 1-1 can transmit a second frame including information indicating that it requests permission to use at least a part of the channel 1002 to the access point device 1-2 using the channel 1002. When the access point device 1-2 receives the second frame, it can transmit a third frame including information indicating whether to permit the access point device 1-1 to use the channel 1002 to the access point device 1-1. The frame including information indicating whether to permit the access point device 1-1 to use the channel 1002 can be the first frame described above.

[0090] The access point device 1-1 according to this embodiment can include in the second frame information indicating a time period (time interval) during which the channel 1002 is used. The second frame can include information indicating a frequency band used by the access point device 1-1 in the channel 1002.

[0091] The access point device 1-1 can transmit the second frame not as a frame addressed to one device but as a frame addressed to a plurality of devices. Here, the access point device 1-1 can include in the second frame information indicating a plurality of communication devices and transmit it. It is desirable that the plurality of communication devices assumed by the access point device 1-1 are communication devices that are assumed to be using the channel 1002. As will be described later, this can be determined by the access point device 1-1 based on the propagation path estimation result associated with the channel 1002. Also, the access point device 1-1 can transmit the second frame as a broadcast frame.

[0092] The access point device (or station device) that has received the second frame transmitted as a frame addressed to a plurality of communication devices determines whether the device itself is using channel 1002 or has reserved channel 1002, and can transmit a third frame to the communication device that is the source of the second frame using channel 1002.

[0093] The access point device 1-2 can transmit the first frame not as a frame addressed to one device but as a frame addressed to a plurality of devices. The access point device 1-2 can include information indicating a plurality of communication devices in the first frame and transmit it. The access point device 1-2 can transmit the first frame as a broadcast frame.

[0094] Prior to transmitting the first frame or the second frame, the access point device 1-1 and the access point device 1-2 can perform a propagation path estimation associated with channel 1002. For example, when the access point device 1-2 permits the access point device 1-1 to use channel 1002, a frame transmitted by the access point device 1-1 using channel 1002 may interfere with the access point device 1-2 and the station device 2-5 that were originally using channel 1002. However, if this interference power is below a predetermined threshold (for example, the allowable interference power of each communication device), even if the access point device 1-1 is transmitting a frame using channel 1002, the access point device 1-2 can also transmit a frame using channel 1002.

[0095] Here, the allowable interference power is not limited to anything, but for example, when a frame with a predetermined MCS (for example, an MCS capable of achieving 22.5 Mbps which is one of the Mandatory Rates) and a predetermined transmission power (for example, the upper limit of the transmission power (antenna power) set by regulations, or EIRP) is received, it can be the interference power with which the frame can be correctly received (decoded without errors). The allowable interference power can be set by each communication device, or can be set to a common value by the communication devices in the connected state.

[0096] The access point device 1-1 can transmit a fourth frame including information requesting the transmission of a reference signal (training field) for propagation path estimation to the access point device 1-2 and the station device 2-5. The access point device 1-1 can transmit the fourth frame to the communication devices belonging to the BSS managed by the access point device 1-2. At this time, the access point device 1-1 can include, in the fourth frame, information associated with the training field transmitted by the communication device that has received the fourth frame. The information associated with the training field can include the signal sequence set in the training field, the amount of phase rotation, and information indicating the radio resources on which the training field is transmitted.

[0097] The access point device 1-1 and the access point device 1-2 can also set a guard band between channel 1001 and channel 1002. The guard band can be newly set between channel 1001 and channel 1002. Also, the guard band can be set as a channel using a part of the band of channel 1001 (for example, the band adjacent to channel 1002) and a part of the band of channel 1002 (for example, the band adjacent to channel 1001).

[0098] The access point device 1-1 can use the guard band when transmitting a frame by using the first frame, the second frame, and the third frame. That is, in the description so far, the communication method that the access point device 1-1 has performed when using the channel 1002 can also be used when the access point device 1-1 uses the guard band for frame transmission.

[0099] Note that since the normal guard band is a frequency band not used for communication, it is not always necessary to secure it by carrier sense prior to frame transmission. However, when the access point device 1-1 uses it for frame transmission, carrier sense is required. The access point device 1-1 according to the present embodiment can perform carrier sense in advance and secure the guard band when using the guard band. For example, after the access point device 1-1 secures the guard band, it can notify surrounding communication devices of using the guard band by using the second frame. At this time, different from the case of using the channel 1002, the second frame can include information indicating that the access point device 1-1 has secured the guard band. The access point device 1-1 can transmit the second frame by using the guard band.

[0100] The access point device 1-1 can transmit a trigger frame that causes the transmission of a reference signal to other communication devices in the guard band. Also, when transmitting a reference signal in the channel 1001, the access point device 1-1 can also transmit a reference signal to the guard band. That is, the access point device according to the present embodiment can transmit a reference signal having a signal bandwidth wider than the signal bandwidth of the reference signal transmitted in the channel 1001 by using the bands of the channel 1001 and the guard band.

[0101] When implementing the method described above, the access point device 1-1 can secure wireless resources that can be set for the method in advance. For example, the access point device 1-1 can set, by means of a beacon frame, a time interval for setting the method in advance. Also, the access point device 1-1 can secure, for a predetermined period, the wireless resources for setting the method in advance by means of a frame for securing a TXOP.

[0102] The access point device according to this embodiment can reject other communication devices from using the channel secured by the own device. For example, the access point device can transmit a frame including information indicating that other communication devices are not permitted to use the channel secured by the own device. For example, the access point device can transmit a frame including information indicating that the second frame is not received (or cannot be received).

[0103] The access point device according to this embodiment can indicate the conditions when other communication devices use the channel secured by the own device. For example, the access point device can notify information associated with the allowable interference power when other communication devices use the channel secured by the own device. Also, the access point device can notify the conditions in advance by means of a beacon frame or a data frame.

[0104] The access point device 1-1 according to this embodiment can impose restrictions on the frames transmitted in channel 1002 secured by the access point device 1-2. For example, the access point device 1-1 can determine whether to use channel 1002 according to the type of frame to be transmitted. Here, the frame type can be distinguished among control frames, management frames, and data frames. Also, the access point device 1-1 according to this embodiment can determine whether to use channel 1002 also according to the frame transmission method. For example, when the frame transmitted by the access point device 1-1 is a frame addressed to a plurality of station devices, it can be set not to use channel 1002.

[0105] The access point device 1-1 according to this embodiment can also determine whether to use the channel according to the frequency band in which channel 1002 is arranged. When the frequency band in which the access point device 1-1 sets the primary channel is different from the frequency band in which channel 1002 is arranged, the access point device 1-1 can be set not to use channel 1002. Here, the frequency band can be distinguished among the 2.4 GHz band, the 5 GHz band, the 6 GHz band, and the 60 GHz band. Also, a plurality of frequency bands can be defined even within the 6 GHz band. For example, when the primary channel of the access point device 1-1 according to this embodiment is set to 5.150 MHz in the 5 GHz band, the access point device 1-1 can be set not to use channel 1002 when channel 1002 is set to 5.250 MHz.

[0106] The access point device 1-1 according to this embodiment can transmit OFDM signals with different subcarrier intervals on channel 1001 and channel 1002. At this time, the OFDM signals transmitted on channel 1001 and channel 1002 may have subcarriers arranged continuously or discontinuously. At this time, the access point device 1-1 can set the subcarrier interval set in the OFDM signal transmitted by the access point device 1-2 on channel 1002 in the OFDM signal transmitted by its own device on channel 1002. The access point device 1-1 can transmit a frame including information indicating the subcarrier interval set in the OFDM signal transmitted by its own device on channel 1001.

[0107] When the access point device 1-1 according to this embodiment transmits a frame on channel 1002, it can transmit synchronously with the frame transmitted by the access point device 1-2 on channel 1002. Here, transmitting synchronously means that when the frames transmitted by the access point device 1-1 and the access point device 1-2 are received by the communication device, the deviation in reception timing is within the guard interval length set in the OFDM signal included in the frame. In this case, the access point device 1-1 and the access point device 1-2 can perform a matching operation (calibration operation) prior to transmitting the frame. Here, the matching operation includes an operation of setting the deviation of the oscillation frequency to less than a predetermined value.

[0108] In addition, in the method described above, the field in which the information is described is not limited to anything. For example, the field in which the information is described can be described in the PHY layer (PHY header). By being described in the PHY header, the communication device can quickly read the information only by demodulation processing in the PHY layer. Also, the field in which the information is described can be described in the MAC layer (MAC header, MAC body). By being described in the MAC layer, the communication device can flexibly adjust the amount of information described.

[0109] According to the method described above, even when the frequency band is pre-divided into a predetermined frequency band, the access point device and the station device can flexibly change the frequency band that can be used for frame transmission, so that it is possible to improve the frequency utilization efficiency. [2. Common to all embodiments]

[0110] The communication device according to the present invention can communicate in a frequency band (frequency spectrum) called an unlicensed band that does not require permission from a country or region, but the available frequency band is not limited to this. The communication device according to the present invention can also exhibit its effects, for example, in a frequency band called a white band that is not actually used for the purpose of preventing interference between frequencies, even though a country or region has given permission to use a specific service (for example, a frequency band assigned for television broadcasting but not used in some regions), or in a shared spectrum (shared frequency band) that is expected to be shared by multiple operators.

[0111] In addition, the communication standard targeted by the communication device according to the present invention is not limited to any particular one. For example, when a communication standard mainly targeted at a frequency band called a licensed band (for which permission to use has been obtained from a country or region) (for example, a communication standard approved as IMT-Advanced by ITU-R or a communication standard approved as IMT-2020) is introduced into an unlicensed band, the communication device can also exhibit its effects in that communication standard.

[0112] The program operating in the wireless communication device according to the present invention is a program (a program that enables a computer to function) for controlling a CPU or the like so as to realize the functions of the above-described embodiment related to the present invention. The information handled by these devices is temporarily stored in the RAM during processing, and then stored in various ROMs and HDDs, and read by the CPU as needed for correction and writing. As the recording medium for storing the program, any of a semiconductor medium (e.g., ROM, non-volatile memory card, etc.), an optical recording medium (e.g., DVD, MO, MD, CD, BD, etc.), a magnetic recording medium (e.g., magnetic tape, flexible disk, etc.), etc. may be used. Also, by executing the loaded program, not only the functions of the above-described embodiment are realized, but also the functions of the present invention may be realized by processing in cooperation with an operating system or other application programs, etc. based on the instructions of the program.

[0113] When distributing on the market, the program can be stored in a portable recording medium for distribution, or transferred to a server computer connected via a network such as the Internet. In this case, the storage device of the server computer is also included in the present invention. Also, a part or all of the communication device in the above-described embodiment may typically be realized as an LSI which is an integrated circuit. Each functional block of the communication device may be chipified individually, or a part or all may be integrated and chipified. When each functional block is integrated into an integrated circuit, an integrated circuit control unit for controlling them is added.

[0114] Also, the method of integrating into an integrated circuit is not limited to LSI and may be realized by a dedicated circuit or a general-purpose processor. Also, when a technology for integrating into an integrated circuit that replaces LSI appears due to the progress of semiconductor technology, it is also possible to use an integrated circuit based on that technology.

[0115] Note that the invention of the present application is not limited to the above-described embodiments. The wireless communication device of the present invention is not limited to being applied to a mobile station device, and can be applied to stationary or non-mobile electronic devices installed indoors or outdoors, such as AV devices, kitchen devices, cleaning and washing devices, air conditioning devices, office devices, vending machines, and other household devices.

[0116] As described above, the embodiments of the present invention have been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and designs and the like within the scope not departing from the gist of the present invention are also included in the claims.

[0117] <Appendix A> [Appendix 1] A first base station device that performs wireless communication with a terminal device, comprising a transmission / reception unit that transmits and receives wireless signals, a resource allocation unit that determines the allocation of frequency resources used for communication with a first terminal device, and a control information generation unit that generates control information. When the first base station device communicates with the first terminal device using a first frequency channel and a second base station device communicates with a second terminal device using a second frequency channel, the resource allocation unit allocates a part of the second frequency channel to the communication between the first base station device and the first terminal device, and the transmission / reception unit communicates with the first terminal device using the first frequency channel and a part of the second frequency channel. A first base station device.

[0118] [Appendix 2] The first base station device according to Appendix 1, wherein the second frequency channel is a frequency channel secured by the second base station device.

[0119] [Appendix 3] The first base station device according to Appendix 2, wherein the control information generation unit generates first control information including information regarding a part of the second frequency channel, and the transmission / reception unit transmits a frame including the first control information to the second base station device.

[0120] [Appendix 4] The transmitting and receiving unit is the first base station device according to Supplementary Note 2, which transmits a frame including information indicating a request for permission to use the second frequency channel to the second base station device.

[0121] [Supplementary Note 5] The transmitting and receiving unit is the first base station device according to Supplementary Note 2, which receives a frame including information indicating permission to use the second frequency channel, transmitted by the second base station device.

[0122] [Supplementary Note 6] The control information generation unit further generates second control information for requesting a report on the channel quality of the second frequency channel in the second base station device to the second base station device. The transmitting and receiving unit transmits the second control information to the second base station device and receives third control information including information on the channel quality of the second frequency channel from the second base station device. The transmitting and receiving unit is the first base station device according to Supplementary Note 2.

[0123] [Supplementary Note 7] The first base station device according to Supplementary Note 6 further includes a channel estimation unit for estimating the channel quality of a frequency channel. The channel estimation unit estimates the channel quality of the first frequency channel and the channel quality of the second frequency channel. The resource allocation unit determines to allocate a part of the second frequency channel for communication between the first base station device and the first terminal device based on the estimated channel quality of the first frequency channel, the estimated channel quality of the second frequency channel, and the information on the channel quality included in the third control information.

[0124] [Supplementary Note 8] The transmitting and receiving unit is the first base station device according to Supplementary Note 1, which transmits a trigger frame requesting transmission of a reference signal in the second frequency channel to at least one of the second base station device and the second terminal device.

[0125] [Supplementary Note 9] A second base station device that performs wireless communication with a terminal device, comprising a transmission / reception unit that transmits and receives wireless signals, and a resource allocation unit that determines the allocation of frequency resources used for communication with a second terminal device. When the second base station device is communicating with the second terminal device using a second frequency channel, if the transmission / reception unit receives first control information including information indicating that a part of the second frequency channel is used by a first base station device, the resource allocation unit excludes a part of the second frequency channel from the allocation for communication with the second terminal device.

[0126] [Appendix 10] The second base station device further comprises a channel estimation unit and a control information generation unit. The transmission / reception unit receives second control information for requesting a report on the channel quality of a second frequency channel used by the second base station device for communication with a second terminal device from the first base station device. The channel estimation unit estimates the channel quality of the second channel in the second base station device. The control information generation unit generates third control information including information on the estimated channel quality of the second channel. The transmission / reception unit transmits the third control information to the first base station device. The second base station device according to claim 9.

[0127] [Appendix 11] The second frequency channel is a frequency channel secured by the second base station device. The second base station device according to Appendix 9 or Appendix 10.

[0128] [Appendix 12] A communication method of a first base station device that performs wireless communication with a terminal device, the method comprising: a step of transmitting and receiving a wireless signal; a step of determining an allocation of frequency resources to be used for communication with a first terminal device; a step of generating control information; when the first base station device communicates with the first terminal device using a first frequency channel and a second base station device communicates with a second terminal device using a second frequency channel, a step of allocating a part of the second frequency channel for communication between the first base station device and the first terminal device; and a step of communicating with the first terminal device using the first frequency channel and a part of the second frequency channel.

[0129] <Appendix B> (1) That is, a base station device according to an aspect of the present invention is a first base station device that performs wireless communication with a terminal device, and includes a transceiver that transmits and receives a wireless signal, a resource allocation unit that determines an allocation of frequency resources to be used for communication with a first terminal device, and a control information generation unit that generates control information. When the first base station device communicates with the first terminal device using a first frequency channel and a second base station device communicates with a second terminal device using a second frequency channel, the resource allocation unit allocates a part of the second frequency channel for communication between the first base station device and the first terminal device, and the transceiver communicates with the first terminal device using the first frequency channel and a part of the second frequency channel.

[0130] (2) Further, a base station device according to an aspect of the present invention is as described in (1) above, and the second frequency channel is a frequency channel secured by the second base station device.

[0131] (3) Further, a base station device according to an aspect of the present invention is as described in (2) above, and the control information generation unit generates first control information including information regarding a part of the second frequency channel, and the transceiver transmits a frame including the first control information to the second base station device.

[0132] (4) Further, the base station apparatus according to one aspect of the present invention is as described in (2) above, and the transmission / reception unit transmits a frame including information indicating a request for the second frequency channel to the second base station apparatus.

[0133] (5) Further, the base station apparatus according to one aspect of the present invention is as described in (2) above, and the transmission / reception unit receives a frame including information indicating permission to use the second frequency channel, which is transmitted by the second base station apparatus.

[0134] (6) Further, the base station apparatus according to one aspect of the present invention is as described in (2) above, and the control information generation unit further generates second control information for requesting a report on the channel quality of the second frequency channel in the second base station apparatus to the second base station apparatus. The transmission / reception unit transmits the second control information to the second base station apparatus and receives third control information including information regarding the channel quality of the second frequency channel from the second base station apparatus.

[0135] (7) Further, the base station apparatus according to one aspect of the present invention is as described in (6) above, and the first base station apparatus further includes a channel estimation unit that estimates the channel quality of the frequency channel in the first base station apparatus. The channel estimation unit estimates the channel quality of the first frequency channel and the channel quality of the second frequency channel, and the resource allocation unit determines to allocate a part of the second frequency channel to the communication between the first base station apparatus and the first terminal apparatus based on the estimated channel quality of the first frequency channel, the estimated channel quality of the second frequency channel, and the information regarding the channel quality included in the third control information.

[0136] (8) Further, the base station apparatus according to one aspect of the present invention is as described in (1) above, and the transmission / reception unit transmits a trigger frame requesting transmission of a reference signal in the second frequency channel to at least one of the second base station apparatus and the second terminal apparatus.

[0137] (9) Further, a base station device according to an aspect of the present invention is a second base station device that performs wireless communication with a terminal device, and includes a transmission / reception unit that transmits and receives wireless signals, and a resource allocation unit that determines an allocation of frequency resources used for communication with a second terminal device. When the second base station device is communicating with the second terminal device using a second frequency channel, and the transmission / reception unit receives first control information including information indicating that a part of the second frequency channel is used by a first base station device, the resource allocation unit excludes a part of the second frequency channel from the allocation for communication with the second terminal device.

[0138] (10) Further, a base station device according to an aspect of the present invention is as described in (9) above, and the second base station device further includes a channel estimation unit and a control information generation unit. The transmission / reception unit receives second control information for requesting a report on the channel quality of a second frequency channel used by the second base station device for communication with a second terminal device from the first base station device. The channel estimation unit estimates the channel quality of the second channel in the second base station device, the control information generation unit generates third control information including information on the estimated channel quality of the second channel, and the transmission / reception unit transmits the third control information to the first base station device.

[0139] (11) Further, a base station device according to an aspect of the present invention is as described in (9) or (10) above, and the second frequency channel is a frequency channel secured by the second base station device.

[0140] (12) Further, a communication method according to an aspect of the present invention is a communication method of a first base station device that performs wireless communication with a terminal device, and includes steps of transmitting and receiving a wireless signal, determining an allocation of frequency resources to be used for communication with a first terminal device, generating control information, and when the first base station device communicates with the first terminal device using a first frequency channel and a second base station device communicates with a second terminal device using a second frequency channel, allocating a part of the second frequency channel for communication between the first base station device and the first terminal device, and communicating with the first terminal device using the first frequency channel and a part of the second frequency channel.

Industrial Applicability

[0141] The present invention is suitable for use in a base station device and a communication method.

Explanation of Signs

[0142] 1-1, 1-2 Access Point Device 2-1~8 Station Device 3-1, 3-2 Management Range 10001-1 Upper Layer Part 10002-1 Autonomous Distributed Control Part 10002a-1 CCA Part 10002b-1 Backoff Part 10002c-1 Transmission Judgment Part 10003-1 Transmission Part 10003a-1 Physical Layer Frame Generation Part 10003b-1 Wireless Transmission Part 10004-1 Reception Part 10004a-1 Wireless Reception Part 10004b-1 Signal Demodulation Part 10005-1 Antenna Part

Claims

1. An access point device for a wireless LAN, A transmitter and a receiver are provided, the transmitting unit and the receiving unit communicate with a station device on a first channel; the transmitting unit transmits a trigger frame notifying permission for at least a portion of a band of a second channel different from the first channel; Access point device.

2. the receiving unit receives a response frame from the station device after transmitting the trigger frame; the transmitting unit and the receiving unit communicate with the station device using at least a portion of a band of the second channel; The access point device according to claim 1 .

3. The receiving unit performs carrier sense prior to transmitting the trigger frame. The access point device according to claim 1 .

4. A station device of a wireless LAN, A transmitter and a receiver are provided, The receiving unit receives a trigger frame transmitted from an access point device on a first channel; The transmission unit transmits a response frame to the trigger frame, the trigger frame is a frame notifying permission for at least a portion of a band of a second channel different from the first channel; Station equipment.

5. the receiving unit receives a wireless signal in at least a part of a band of the second channel after the transmitting unit transmits the response frame.

5. A station device according to claim 4.

6. A communication method for a wireless LAN access point device, comprising: communicating with the station device over a first channel; transmitting a trigger frame notifying a grant for at least a portion of a band of a second channel different from the first channel; Communication methods.

7. A communication method for a station device of a wireless LAN, comprising: receiving a trigger frame transmitted on a first channel from an access point device; transmitting a response frame to the trigger frame; the trigger frame is a frame notifying permission for at least a portion of a band of a second channel different from the first channel; Communication methods.

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