Communication device

Abstract

[Problem] To provide a communication device capable of performing communication by using a non-primary channel, even if a primary channel is in use. [Solution] A communication device according to the present disclosure comprises a control unit that controls a wireless communication unit that performs wireless communication with another communication device by using first to n-th access channels (where n is an integer of 2 or greater). The control unit executes access control on a first access channel set to a primary channel, and performs control to implement the access control on a second access channel set to a channel other than the primary channel, on the basis of a situation in which it has been determined that the first access channel cannot be used.

Description

communication equipment

[0001] The present disclosure relates to a communication device.

[0002] In CSMA / CA operation in a wireless LAN system, if a communication device detects that a surrounding communication device is using the primary channel, the device itself cannot transmit.

[0003] In recent years, communication devices have been standardized to enable high-speed, large-capacity data transmission by utilizing Channel Bonding technology, which bundles and simultaneously uses multiple channels adjacent to multiple 20 MHz bandwidth primary channels.

[0004] For example, a communication device can use one secondary channel adjacent to the primary channel to provide a 40 MHz bandwidth, or another secondary channel to provide an 80 MHz bandwidth. Another standardized technology allows communication devices to combine two 80 MHz bandwidths for a total bandwidth of 160 MHz.

[0005] Special table 2017-521944 publication Special table 2023-541018 publication

[0006] IEEE802.11-23 / 961r0

[0007] In the above-described technology, even if the primary channel is busy, the communication device transmits data using an available secondary channel after a backoff time has elapsed. However, unless the transmitting and receiving sides of the communication device simultaneously grasp which secondary channels are available, each communication device may see different secondary channel usage statuses, leading to a problem that the transmitting side may start transmission on a secondary channel that is unavailable to the receiving side.

[0008] Furthermore, a method has been proposed that applies this technology to carry out data transmission using other available secondary channels even when the primary channel is in use.

[0009] In addition, in the above-mentioned technology, in a multi-link device (also called MLD) capable of multi-link operation using links of different frequency bands, the transmitting communication device notifies the receiving communication device of the status of the primary channel. However, while these technologies can be used to exchange information about available secondary channels between AP-MLD and Non-AP MLD, there is a problem in that this information cannot be exchanged between communication devices that are not MLD-compatible or in situations where Non-AP MLD cannot use links in some frequency bands.

[0010] Furthermore, with the recent spread of wireless LAN systems, communication devices within a wireless LAN system may form adjacent networks, and interference from other systems may also be a problem.

[0011] In view of these problems, the present disclosure provides a communication device that is capable of communication using a non-primary channel even when the primary channel is in use.

[0012] The communication device disclosed herein includes a control unit that controls a wireless communication unit that performs wireless communication with other communication devices using first to nth access channels (n is an integer greater than or equal to 2), and the control unit performs access control using a first access channel that is set as a primary channel, and, based on a situation in which it is determined that the first access channel is unavailable, controls the access control to be performed using a second access channel that is set other than the primary channel.

[0013] 1 shows an example of the overall configuration of a wireless LAN system 200 in the first embodiment. It shows examples of signal detection levels in the primary channel and the secondary channel. It shows an example of frequency channels used in the wireless LAN system 200 in the first embodiment. It shows an example of a multi-channel configuration used in the wireless LAN system 200 in the first embodiment. It shows an example of the temporal progression of each channel used by the transmitting communication device 1 in the first embodiment. It shows another example of the temporal progression of each channel used by the first embodiment. It shows an operation of identifying a non-primary channel available in the transmitting communication device 1 in the first embodiment. It shows an operation of identifying a non-primary channel available in the receiving communication device 2 in the first embodiment. It shows an example of setting a predetermined waiting time for the first access channel in the first embodiment. It shows a specific example of the predetermined waiting time for the first access channel in the first embodiment. It shows an example of a frame configuration of a communication device in the first embodiment. It shows a specific example of the predetermined waiting time for the second to n-th access channels in the first embodiment. It is a block diagram showing an example of the configuration of a communication device in the first embodiment. It is a block diagram showing an example of the configuration of a wireless communication unit 15, etc. in the first embodiment. It is another block diagram of a communication device in the first embodiment. 1 is an example of a setting status of a window waiting time of a transmitting communication device 1 in the first embodiment. FIG. 2 is an example of a channel allocation in the first embodiment. FIG. 3 is an example of a channel allocation in a comparative example. FIG. 4 is an example of an association operation of a communication device in the first embodiment. FIG. 5 is an example of a parameter exchange of a channel transition operation in the first embodiment. FIG. 6 is an example of an information element when setting parameters of a communication device in the first embodiment. FIG. 7 is an example of a flowchart when a transmitting communication device 1 in the first embodiment performs access control. FIG. 8 is an example of a flowchart when a receiving communication device 2 in the first embodiment performs reception control. FIG. 9 is an example of a time transition of each channel used by a transmitting communication device 1 in the second embodiment. FIG. 10 is a block diagram showing an example of the hardware configuration of a computer that executes a series of processes according to the first or second embodiment by a program. FIG. 11 is a block diagram showing a schematic configuration example of a smartphone to which the first or second embodiment is applied.1 is a block diagram showing an example of a schematic configuration of an in-vehicle device to which the first or second embodiment is applied, and FIG. 2 is a block diagram showing an example of a schematic configuration of a wireless AP to which the first or second embodiment is applied.

[0014] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In this specification and the drawings, components having substantially the same functional configurations are designated by the same reference numerals, and their description will be omitted as appropriate. The drawings are simplified, and components necessary for implementation other than those shown in the drawings are also included as appropriate. Furthermore, when terms such as "first" and "second" are used in this specification or claims, unless otherwise specified, they do not represent any order or importance, but are used to distinguish one configuration from another.

[0015] First Embodiment FIG. 1 shows an example of the overall configuration of a wireless LAN system 200 according to a first embodiment.

[0016] In this embodiment, in addition to wireless LAN base stations conforming to the IEEE802.11 standard, such as the transmitting communication device 1 and the receiving communication device 2, terminal devices are also used as examples of communication devices. However, a chip realized by one or more LSIs and including a wireless communication unit, which will be described later, may also be called a communication device.

[0017] The wireless LAN system 200 in this embodiment can use, for example, the 2.4 GHz band, the 5 GHz band, or the 6 GHz band, and each band is subdivided into frequencies that are used, and are called channels.

[0018] In the wireless LAN system 200, moving communication devices may exist around the transmitting communication device 1. In addition, an overlapping network exists around the network of the transmitting communication device 1, and the communication devices that make up that network are configured to operate according to the same access control procedure as the transmitting communication device 1.

[0019] This diagram also shows an example in which a transmitting communication device 1 transmits data to a receiving communication device 2 via wireless communication using a secondary channel in the direction indicated by the arrow. This diagram also shows that a transmitting OBSS (Overlapping BSS) 3 exists as a communication device on the left side of the transmitting communication device 1, and a receiving OBSS 3' exists on the right side of the receiving communication device 2.

[0020] For each communication device, the outer dashed line indicates the signal reachability range of that communication device, which in this example is represented as the detection range of received field strength on the primary channel. Also, for each communication device, the inner dashed line indicates the range of signal strength lower than the outer dashed line, which in this example is represented as the detection range of received field strength on the secondary channel.

[0021] FIG. 2 shows an example of signal detection levels on the primary and secondary channels.

[0022] A primary channel is an operating channel common to all communication stations (STAs) that are members of a basic service set (BSS). For example, in a 20 MHz, 40 MHz, 80 MHz, 160 MHz, or 80+80 MHz BSS, the primary channel is the 20 MHz channel.

[0023] A secondary channel is a channel associated with a primary channel and used to create a wider channel than the primary channel. In a 40 MHz, 80 MHz, 160 MHz, or 80+80 MHz BSS, a secondary channel is a 20 MHz channel.

[0024] In Figure 2, P20, P40, and P80 represent the signal detection threshold and energy detection threshold in dBm as signal detection levels when using a primary channel alone, when using a secondary channel adjacent to the primary channel to use a 40 MHz bandwidth, and when using one secondary channel to use radio waves with an 80 MHz bandwidth.

[0025] Also, in Figure 2, S20, S40, and S80 represent the signal detection threshold and energy detection threshold in dBm as detection levels when using a secondary channel alone, when using a secondary channel adjacent to a secondary channel to use a 40 MHz bandwidth, and when using one secondary channel to use radio waves with an 80 MHz bandwidth.

[0026] As shown in Figure 2, the signal detection threshold when using the primary channel (P20) alone is -82 dBm, and the signal detection threshold when using the secondary channel (S20) alone is -72 dBm. Figure 2 also shows that there are differences depending on the channel bandwidth.

[0027] Here, explanation will be given again with reference to Figure 1. Focusing on the received field strength of the transmitting OBSS 3 and the receiving OBSS 3' (gray areas in Figure 1), the transmitting communication device 1 and the receiving communication device 2 will detect signals from the transmitting OBSS 3 and the receiving OBSS 3', respectively, on the primary channel, but will not detect any signals on the secondary channel.

[0028] In this embodiment, a method is described in which, when a transmitting communication device 1 transmits data, even if the primary channel is unavailable, the receiving communication device 2 communicates using a non-primary channel that is not subject to interference from communication devices such as OBSS 3.

[0029] A non-primary channel is selected from channels other than the primary channel. A secondary channel is an example of a non-primary channel. For the sake of explanation, the following description will mainly use the secondary channel as the non-primary channel.

[0030] FIG. 3 shows an example of frequency channels used in the wireless LAN system 200 in the first embodiment.

[0031] In this embodiment, the wireless LAN system 200 can use radio waves in the 2.4 GHz band, the 5 GHz band, and the 6 GHz band, and each band is subdivided according to the frequency used.

[0032] In these frequency bands, the bandwidth is defined for each standard used. The IEEE802.11a, IEEE802.11g, IEEE802.11n, IEEE802.11ac, IEEE802.11ax, and IEEE802.11be standards, which use the OFDM (Orthogonal Frequency Division Multiplex) signal format, define a channel width of 20 MHz, and in the 2.4 GHz band shown in Figure 3A, three channels, shown in black, are allocated.

[0033] Furthermore, in terms of channel allocation, 5 GHz band A shown in Figure 3B has channels 8 to 10 based on the legal system of each country, 5 GHz band B shown in Figure 3C has channels 11 to 13 (e.g., the area shown in black), and 5 GHz band C also shown in Figure 3C has channels 5 to 7 (e.g., the area shown in gray).

[0034] In terms of channel allocation, 6 GHz band A (Unii-5) shown in Figure 3D has 25 channels shown in black, 6 GHz band B (Unii-6) also shown in Figure 3D has 5 channels shown in gray, 6 GHz band C (Unii-7) shown in Figure 3E has 17 channels shown in black, and 6 GHz band D (Unii-8) has 12 channels shown in gray.

[0035] FIG. 4 shows an example of a multi-channel configuration used in the wireless LAN system 200 according to the first embodiment.

[0036] In this embodiment, the wireless LAN system 200 uses a mechanism for carrying out communication using channels with a bandwidth of 20 MHz, in addition to a channel configuration with a bandwidth of 40 MHz formed by combining two channels through channel bonding, a bandwidth of 80 MHz formed by combining four channels, and a bandwidth of 160 MHz formed by combining eight channels.

[0037] 4A to 4F respectively show examples of channel configurations in the 6 GHz band for bandwidths of 20 MHz, 40 MHz, 80 MHz, and 160 MHz, as well as for bandwidths of 320 MHz and 640 MHz, which are expected to be standardized in the future. For example, FIG. 4 shows that 14 channels can be configured for an 80 MHz bandwidth, and 7 channels can be configured for a 160 MHz bandwidth. The communication device of this embodiment can also be applied to such bandwidths.

[0038] FIG. 5 shows an example of the time transition of each channel used by the transmitting communication device 1 of the first embodiment.

[0039] In this embodiment, the sending communication device 1 and the receiving communication device 2 predetermine the order of the secondary channels (S20) to be used as non-primary channels when the primary channel (P20) is unavailable, and if any of the channels is available, communication is carried out using those channels.

[0040] In this example, the transmitting communication device 1 uses the primary channel as the first access channel, and if the primary channel is unavailable, it predetermines the second to fifth access channels from the secondary channels and performs access control in this order.

[0041] Access control refers to a process of checking whether a specific channel is available for use by a station so that a signal to be transmitted by the station does not interfere with signals transmitted from or received by other stations. Access control includes, for example, physical carrier sensing (CCA: Clear Channel Assessment) as well as virtual carrier sensing, such as determination based on RTS (Request to Send), CTS (Clear to Send), and NAV (Network Allocation Vector). An access channel refers to a wireless channel that is subject to access control processing.

[0042] The transmitting communication device 1 performs access control on the first access channel, and if it determines that this channel is unavailable, it performs access control on the second access channel, which will be the next access channel. In this example, the transmitting communication device 1 transmits a predetermined first signal on the first access channel after a DIFS (DCF Inter Frame Space) and a random backoff time, and then performs access control to enable data transmission after receiving a second signal. For ease of explanation, the time for preamble detection and the like is omitted in FIG. 5. Note that the diamond-shaped portion of the first access channel in the figure indicates that there are multiple slots in the contention window during the random backoff time.

[0043] If the transmitting communication device 1 detects BUSY on the first access channel during the waiting time, for example, if transmission has started from another OBSS, or if the NAV has been set by the CTS signal of another OBSS and the device is in a virtual carrier detection state, it determines that the channel is unavailable and, after the maximum value of a predetermined waiting time (hereinafter, the predetermined waiting time will be explained using an example of window waiting time) has elapsed, switches the frequency channel to the second access channel (hereinafter, also referred to as transition) and performs access control on that channel.

[0044] When the transmitting communication device 1 detects a BUSY signal in the second access channel, as with the first access channel, it switches to the third access channel frequency channel after a predetermined waiting time has elapsed and performs access control for that channel.When the transmitting communication device 1 detects a BUSY signal in the third access channel, as with the first access channel, it switches to the fourth access channel frequency channel after a predetermined waiting time has elapsed and performs access control for that channel.When the transmitting communication device 1 detects a BUSY signal in the fourth access channel, as with the first access channel, it switches to the fifth access channel frequency channel after a predetermined waiting time has elapsed and performs access control for that channel.

[0045] Furthermore, when the transmitting communication device 1 detects BUSY on the fifth access channel in the same way as on the first access channel, it returns to the first access channel, which is the original primary channel, and performs access control.

[0046] For example, the predetermined waiting time for the first access channel is set to the maximum value of the contention window CWmin from the EDCA parameters based on the access category (AC) of the data to be transmitted. The predetermined waiting time may be set to a waiting time shorter than this time. Furthermore, the respective time lengths may be set according to the signal format MCS (Modulation and Coding Scheme) used for communication.

[0047] For example, the predetermined waiting time for the second to nth access channels may be set as the timing from when a transmitting communication device 1 transmits a first signal indicating a request to start communication or use a channel to another communication device until when a receiving communication device 2 transmits a second signal indicating that communication can be started or that the channel is available, in response. A conventional RTS is an example of a first signal indicating a request to start communication, and a conventional CTS is an example of a second signal indicating that communication can be started. Furthermore, the first signal indicating a request to use a channel is a newly defined signal different from the conventional RTS, and the second signal indicating that the channel is available is a newly defined signal different from the conventional CTS. In the following example, for the sake of explanation, an RTS will be used as the first signal, and a CTS will be used as the second signal.

[0048] Also, in this example, the transmitting communication device 1 determines the second to fifth access channels from among the secondary channels and performs access control for the receiving communication device 2, but the number of access channels is not limited to this. The number of access channels may be determined in advance by negotiation between the transmitting communication device 1 and the receiving communication device 2 before performing access control, with n access channels being the first to n-th access channels (n is an integer equal to or greater than 2). The transmitting communication device 1 may perform access control in the order of, for example, second, third, ..., n-1, n.

[0049] Furthermore, the order of the access channels for which access control is performed may be determined in advance before the access control is performed by negotiation between the transmitting communication device 1 and the receiving communication device 2. For example, the transmitting communication device 1 may perform access control in an order other than the order of 2, 3, ... n-1, n. The negotiation is performed, for example, by a parameter exchange sequence between the transmitting communication device 1 and the receiving communication device 2, which will be described later.

[0050] If the transmitting communication device 1 determines that the last channel determined by negotiation among the second to n-th access channels is unavailable, it returns to the first access channel and performs access control.

[0051] Furthermore, the communication device may use a predetermined frequency band set as a secondary channel for at least one of the second to n-th access channels, which are non-primary channels. Furthermore, as long as this condition is satisfied, at least one of the second to n-th access channels may be selected from channels that are not included in the predetermined frequency bandwidth set as the primary channel and the secondary channel.

[0052] Furthermore, the bandwidth of each access channel is not limited to 20 MHz, and may be selected from any bandwidth other than 20 MHz, such as a 40 MHz bandwidth, an 80 MHz bandwidth, or a 160 MHz bandwidth.

[0053] FIG. 6 shows another example of the time progression of each channel used in the first embodiment.

[0054] In the above example, the transmitting communication device 1 defines the time from transmitting an RTS to receiving a CTS on the second to nth access channels as the predetermined waiting time. In this example, the transmitting communication device 1 sets the predetermined waiting time on the second to nth access channels without including the time it takes for the CTS transmitted from the receiving communication device 2 to be received. In other words, the transmitting communication device 1 sets the predetermined waiting time to include only the time it takes for the RTS transmitted from the transmitting communication device 1 to be received by the receiving communication device 2.

[0055] This allows the transmitting communication device 1 to perform control so as to transition to more channels in a shorter period.

[0056] FIG. 7 shows the operation of identifying available non-primary channels in the transmitting communication device 1 in the first embodiment.

[0057] In this example, the first to nth access channels (n=5) are set as access channels, and the transmitting communication device 1 starts access control from the first access channel and then sequentially shifts to the other channels, eventually starting data transmission using the fifth access channel.

[0058] In the first to fifth access channels in the diagram, an upward convex state indicates signal transmission, and a downward convex state indicates signal reception. The horizontal axis indicates the time axis. R in the diagram indicates RTS transmission, and C in the diagram indicates CTS reception. Data in the diagram indicates data transmission.

[0059] In this example, the transmitting communication device 1 uses the timing at which communication on the primary channel ends or the timing at which the R-TWT Service Period starts as a reference, and after transmitting an RTS on the first to fifth access channels using the access control described in Figure 5 from that timing, if the transmitting communication device 1 receives a CTS addressed to itself from the receiving communication device within a specified waiting time, it uses that channel to transmit data.

[0060] If it is determined that the first access channel is available and in an IDLE state, the transmitting communication device 1 transmits an RTS after the random backoff time has elapsed.

[0061] Here, when the transmitting communication device 1 receives a CTS addressed to itself from the receiving communication device 2, the transmitting communication device 1 is configured to start data transmission, and the operation is compatible with conventional access control procedures.

[0062] If the transmitting communication device 1 does not receive a CTS addressed to itself in the first access channel, it determines that the channel is in a BUSY state and cannot be used by the receiving communication device 2, and after a predetermined waiting time has elapsed, it transitions to the second access channel, performs access control, and transmits an RTS signal. If the transmitting communication device 1 receives a CTS addressed to itself from the receiving communication device 2, it starts data transmission. In this example, the transmitting communication device 1 does not receive a CTS in the first access channel.

[0063] If the transmitting communication device 1 does not receive a CTS addressed to itself in the second access channel, it determines that the channel is in a BUSY state and cannot be used by the receiving communication device 2, and after a predetermined waiting time has elapsed, it transitions to the third access channel, performs access control, and transmits an RTS signal. If the transmitting communication device 1 receives a CTS addressed to itself from the receiving communication device 2, it starts data transmission. In this example, the transmitting communication device 1 does not receive a CTS in the second access channel.

[0064] If the transmitting communication device 1 does not receive a CTS addressed to itself in the third access channel, it determines that the channel is in a BUSY state and cannot be used by the receiving communication device 2, and after a predetermined waiting time has elapsed, it transitions to the fourth access channel, performs access control, and transmits an RTS signal. If the transmitting communication device 1 receives a CTS addressed to itself from the receiving communication device 2, it starts data transmission. In this example, the transmitting communication device 1 does not receive a CTS in the third access channel.

[0065] If the transmitting communication device 1 does not receive a CTS addressed to itself in the fourth access channel, it determines that the channel is in a BUSY state and cannot be used by the receiving communication device 2, and after a predetermined waiting time has elapsed, it transitions to the fifth access channel, performs access control, and transmits an RTS signal. If the transmitting communication device 1 receives a CTS addressed to itself from the receiving communication device 2, it starts data transmission. In this example, the transmitting communication device 1 does not receive a CTS in the fourth access channel.

[0066] If the transmitting communication device 1 does not receive a CTS addressed to itself in the fifth access channel, it determines that the channel is in a BUSY state and cannot be used by the receiving communication device 2, and after a predetermined waiting time has elapsed, it transitions to the first access channel, performs access control, and transmits an RTS signal. If the transmitting communication device 1 receives a CTS addressed to itself from the receiving communication device 2, it starts data transmission. In this example, the transmitting communication device 1 receives a CTS in the fifth access channel.

[0067] In the fifth access channel, the transmitting communication device 1 receives a CTS addressed to itself, and therefore determines that this channel is in an IDLE state, and starts data transmission.

[0068] FIG. 8 shows the operation of identifying available non-primary channels in the receiving communication device 2 in the first embodiment.

[0069] The receiving communication device 2 waits for an RTS, data, etc. addressed to the receiving device 2 on that channel for a predetermined waiting time from the timing when communication with the transmitting communication device 1 ends or the start of the R-TWT Service Period. Here, the standby operation means "being in a state where wireless signals transmitted on a predetermined channel (frequency band) can be received." The dashed line in the figure indicates that the receiving communication device 2 waits for an RTS on that channel within the predetermined waiting time. If the receiving communication device 2 does not receive an RTS from the transmitting communication device 1 within the predetermined waiting time, it determines that the channel is unavailable and moves on to the next channel to wait for an RTS. The receiving communication device 2 repeats the standby operation until it finds a channel that the transmitting communication device 1 can use.

[0070] The receiving communication device 2 transmits a CTS on the channel on which it received an RTS from the transmitting communication device 1, if that channel is available, and receives data transmitted thereafter. The window waiting time of the receiving communication device 2 is set by a parameter exchange sequence between the transmitting communication device 1 and the receiving communication device 2, which will be described later, so that the predetermined waiting time for each channel of the transmitting communication device 1 is the same for both devices.

[0071] This example corresponds to the example of the transmitting communication device 1 in Figure 7 and shows the operation of the receiving communication device 2 at that time. That is, the receiving communication device 2 transmits a CTS from the first to fourth access channels because the first to fourth access channels are in a busy state and the fifth access channel is in an idle state. In other words, these channels indicate that they are detecting a signal from an OBSS communication device or that they have received a CTS from the OBSS communication device and have set the NAV.

[0072] In the first access channel, the receiving communication device 2 performs a standby operation, and if it does not detect an RTS addressed to itself due to a BUSY state or the like before the expiration of a predetermined window duration, or if it detects an RTS addressed to itself but the NAV is set, it transitions to the second access channel and performs a standby operation. In this example, the receiving communication device 2 does not receive an RTS in the first access channel.

[0073] In the second access channel, the receiving communication device 2 performs a standby operation, and if it does not detect an RTS addressed to itself before the duration of a predetermined window expires, or if it detects an RTS but the NAV is set, it transitions to the third access channel and performs a standby operation. In this example, the receiving communication device 2 does not receive an RTS in the second access channel.

[0074] In the third access channel, the receiving communication device 2 performs a standby operation, and if it does not detect an RTS addressed to itself before the duration of a predetermined window expires, or if it detects an RTS but the NAV is set, it transitions to the fourth access channel and performs a standby operation. In this example, the receiving communication device 2 does not receive an RTS in the third access channel.

[0075] In the fourth access channel, the receiving communication device 2 performs a standby operation, and if it does not detect an RTS addressed to itself before the duration of a predetermined window expires, or if it detects an RTS but the NAV is set, it transitions to the fifth access channel and performs a standby operation. In this example, the receiving communication device 2 does not receive an RTS in the fourth access channel.

[0076] In the fifth access channel, the receiving communication device 2 performs a standby operation, and if it does not detect an RTS addressed to itself before the duration of a predetermined window expires, or if it detects an RTS but the NAV is set, it transitions to the first access channel and performs a standby operation. In this example, the receiving communication device 2 receives an RTS in the fifth access channel.

[0077] In the fifth access channel, the receiving communication device 2 receives an RTS addressed to itself, and if a TXOP is not set, it transmits a CTS from this channel.

[0078] FIG. 9 shows an example of setting the predetermined waiting time for the first access channel in the first embodiment.

[0079] A method for setting a window waiting time as a predetermined waiting time in the first access channel when the transmitting communication device 1 performs access control will be described.

[0080] In this example, the slot time of each contention window CWmin is 9 μs, and as described above, the maximum predetermined waiting time of the transmitting communication device is the sum of the maximum values ​​of DIFS and contention window CWmin, plus the predetermined processing time such as preamble detection.

[0081] For example, the window in the first access channel, i.e., the primary channel, may be configured to start at a time corresponding to the time when the transmitting communication device 1 becomes available in the network, such as the time when beacon transmission at a predetermined beacon transmission time ends, the time when transmission from the access point ends, or the timing of the start of the service period in R-TWT (Restricted Target Wake Time).

[0082] The random backoff time setting expires before the contention window CWmin reaches its maximum value, and so at that timing a signal is transmitted from the transmitting communication device 1. On the other hand, if the receiving communication device 2 knows the timing at which this maximum value is reached, it can wait for a signal from the transmitting communication device 1 and can detect the signal even if it is transmitted before the random backoff time reaches its maximum value.

[0083] The window duration (also referred to as "Duration") of the primary channel may be set to the maximum value of the contention window CWmin according to the EDCA access category. Alternatively, the contention window CWmin duration of the primary channel may be set to a time shorter than the maximum value of the contention window CWmin of the original access category. The predetermined waiting time in the first access channel may be referred to as a first waiting time.

[0084] FIG. 10 is a specific example of the predetermined waiting time for the first access channel in the first embodiment.

[0085] In FIG. 10, examples of window settings will be described using voice (AC_VO), video (AC_VI), best effort (AC_BE), and background (AC_BG) as access categories.

[0086] This example shows a setting value calculated based on conventional access control. The setting value of the window in this embodiment is not limited to this value, and may be set to, for example, a value shorter than the value shown in the figure.

[0087] For example, for voice, the setting values ​​are: the window size of the contention window CWmin is set between 0 and 3, and the slot time of this window is set to 9 μs. The setting values ​​are also: the DIFS period is set to 34 μs, and the preamble detect time is set to 8 + 8 + 4 μs. In this case, the window waiting time of the primary access channel is set to 83 μs, with a slight margin of 2 μs.

[0088] In this example, the DIFS period is calculated as a required period, but if the transmitting communication device 1 is able to transmit a signal at a timing shorter than this, the DIFS period may be subtracted to set the window waiting time for the first access channel.

[0089] FIG. 11 shows an example of a frame configuration of a communication device in the first embodiment.

[0090] In this embodiment, a configuration including a preamble is shown for frames used in communication by a communication device. The window durations for the second to nth access channels, i.e., secondary channels, are calculated based on the frame configuration shown in Figure 11. This frame may be included in the first signal.

[0091] As shown in Figure 11A, in this embodiment, the frame configuration is a short training sequence (8 μs), a long training sequence (8 μs), an L-SIG (4 μs), and, as necessary, a SIGNAL field, data as a MAC header, or an additional training field. The training sequence is a signal transmitted by a communication device to learn channel characteristics. Note that the length of one symbol in these data portions varies depending on the MCS. Note that these symbols are configured to include guard intervals, and therefore, these guard intervals are represented as gaps.

[0092] The window durations for the second through nth access channels are calculated based on the minimum required time as described above.

[0093] As shown in FIG. 11B, when the time for each interframe space is listed, the results are SIFS: 16 μs, PIFS: 25 μs, and DIFS: 34 μs. These values ​​may be used as needed when calculating the window waiting time.

[0094] FIG. 12 shows a specific example of the predetermined waiting times for the second to nth access channels in the first embodiment.

[0095] The predetermined waiting times of the second to nth access channels are set as the time during which RTS and CTS can be exchanged depending on the MCS. For example, in the case of MCS0, RTS and CTS are set to 52 μs and 44 μs, respectively. As shown in FIG. 12 , the windows of the second to nth access channels may be set in the range of 64 μs to 112 μs depending on the MCS used for communication between the sending communication device 1 and the receiving communication device 2.

[0096] FIG. 13 is a block diagram showing an example of the configuration of a communication device according to the first embodiment.

[0097] The communication device of this embodiment (here, the transmitting communication device 1 is taken) determines in advance the order of the non-primary channels to be used, and if it determines that the first channel is unavailable, it attempts transmission on the subsequent channels in order until it finds an available channel. In the example of Figure 13, the transmitting communication device 1 is taken as an example of the communication device, but the receiving communication device 2 has a similar configuration. The predetermined waiting time for the second to nth access channels may also be referred to as the second waiting time.

[0098] The communication device in this embodiment includes an internet connection unit 11 , an information input unit 12 , a control unit 13 , an information output unit 14 and a wireless communication unit 15 .

[0099] The Internet connection unit 11 is configured to implement functions such as a communication modem for connecting to the Internet network when the communication device operates as an access point, for example, and implements an Internet connection consisting of an optical fiber line, a wired line, or a wireless communication line via an Internet service provider.

[0100] The information input unit 12 receives, for example, input of information conveying instructions from a user. The information input unit 12 may be configured as, for example, push buttons or a keyboard, or may receive input of information via a user interface such as a GUI, in which case it may be configured as a touch panel or the like.

[0101] The control unit 13 is configured to, for example, control the wireless communication unit 15, operate the communication device as an access point, and perform the first to n-th access channels in this embodiment. The detailed configuration of the control unit 13 will be described later.

[0102] The information output unit 14 is a part that specifically displays the operating status of the communication device and information obtained via the Internet, and is composed of display elements such as an LED display, a liquid crystal panel, an organic light-emitting diode (OLED) display, and a speaker that outputs music, and is configured to display and notify the user of the information they need.

[0103] The wireless communication unit 15 is configured to perform wireless communication with other communication devices, for example, under the control of the control unit 13. The configuration of the wireless communication unit 15 will be described later.

[0104] Furthermore, the control unit 13 may perform part of the operations of the wireless communication unit 15. The wireless communication unit 15 and the control unit 13 may be configured as a single block. For example, if the wireless communication unit 15 and the control unit 13 are configured as a single block, this block corresponds to the control unit.

[0105] FIG. 14 is a block diagram showing an example of the configuration of the wireless communication unit 15 in the first embodiment.

[0106] The wireless communication unit 15 includes a channel management unit 303, a frame construction unit 304, an available channel determination unit 305, a primary channel setting unit 306, a secondary channel setting unit 307, a transmission signal processing unit 308, an access control unit 309, a received signal detection unit 311, a CCA (Clear Channel Assessment) determination unit 312, a frame analysis unit 313, and a NAV setting unit 314. These blocks are controlled by the control unit 13.

[0107] The blocks shown by dashed lines, namely, channel management unit 303, frame construction unit 304, available channel determination unit 305, primary channel setting unit 306, secondary channel setting unit 307, transmission signal processing unit 308, access control unit 309, received signal detection unit 311, CCA (Clear Channel Assessment) determination unit 312, frame analysis unit 313 and NAV setting unit 314, may be implemented as functions of control unit 13.

[0108] The wireless communication unit 15 also includes an interface 301 that is connected to other blocks and exchanges various information and data with those blocks. The wireless communication unit 15 also includes a transmission buffer 302 that stores data to be transmitted, a reception buffer 315 that stores received data, and an antenna unit 310 that transmits and receives signals to and from other communication devices.

[0109] The channel management unit 303 manages the first to nth access channels. For example, this information is information input in advance by the user via the information input unit 12. This information is also transmitted to other blocks via the interface 301 and output to, for example, the information output unit 14.

[0110] The frame construction unit 304 constructs data frames and management frames to be transmitted by the transmitting communication device 1. The frame construction unit 304 constructs frames based on, for example, data temporarily stored in the transmission buffer 302 and information transmitted from the available channel determination unit.

[0111] The available channel determining section 305 determines the first to n-th access channels as available channels based on the information managed by the channel managing section 303, and sets the duration of the window.

[0112] The primary channel setting unit 306 sets the primary channel determined to be available by the available channel determining unit 305 as the first access channel.

[0113] The secondary channel setting unit 307 sets the second to n-th access channels from the secondary channels determined to be available by the available channel determination unit 305. Furthermore, when each of the second to n-th access channels transitions, the secondary channel setting unit 307 sets the corresponding channel. For the sake of explanation, this block is referred to as the secondary channel setting unit 307, but even when the second to n-th access channels are selected from outside the secondary channel band, the channel setting is performed by this block. Furthermore, when the second to n-th access channels are selected from outside the secondary channel band, an out-of-band access channel setting unit different from the primary channel setting unit 306 and the secondary channel setting unit 307 may be provided, and the setting of the corresponding channel may be performed by this block.

[0114] The transmission signal processing unit 308 constructs, as a transmission signal, each frame constructed by the frame construction unit 304. The transmission signal processed by the transmission signal processing unit 308 is transmitted to the receiving communication device 2 via the antenna unit 310. The transmission signal processing unit 308 also constructs a transmission signal when the access control unit 309 performs access control.

[0115] The access control unit 309 performs access control by timing DIFS, random backoff, etc. on the corresponding channel among the first to nth channels set by the primary channel setting unit 306 or the secondary channel setting unit 307. The result of the access control is sent to the available channel determination unit 305, and based on this information, the secondary channel setting unit 307 sets the next access channel to transition to.

[0116] The received signal detection unit 311 detects a received signal received via the antenna unit 310. For example, in the transmitting communication device 1, the received signal detection unit 311 detects a request frame regarding the setting status of a secondary channel, a CTS, and the like as received signals, and in the receiving communication device 2, the received signal detection unit 311 detects an RTS and the like as received signals.

[0117] The CCA determination unit 312 determines the availability of a channel according to the type of channel and the strength of the received signal detected by the received signal detection unit 311. For example, the CCA determination unit 312 determines the availability of a channel by determining whether the channel is busy or not based on the strength of the received signal. The available channel determination unit 305 may take into account the availability of the channel determined by the CCA determination unit 312 when making the determination.

[0118] The frame analysis unit 313 analyzes frames from the received signal detected by the received signal detection unit 311. For example, the frame analysis unit 313 extracts predetermined header information from the received signal and extracts information contained in the frame. The received signal analyzed by the frame analysis unit 313 is temporarily stored in the receive buffer 315.

[0119] The NAV setting unit 314 sets the NAV based on the header information extracted by the frame analysis unit 313. For example, if the header information included in the received signal indicates that the communication path will be used for a predetermined period of time, the NAV setting unit 314 sets the NAV for the target communication device. Furthermore, information on the NAV setting may be transmitted to the available channel determination unit 305 and used to determine whether the channel is unavailable.

[0120] In this embodiment, a request frame or a response frame regarding the setting status of a secondary channel received from the receiving communication device 2 is analyzed by the frame analysis unit 313. As a result of the analysis, the available channel determination unit 305 determines an available channel and notifies the channel management unit 303. As a result, a channel available to the transmitting communication device 1 and the receiving communication device 2 is set, and the available channel determination unit 305 transmits this information to the frame construction unit 304. The frame construction unit 304 constructs a management frame or an action frame as a response frame regarding the setting status of the secondary channel, and these frames are processed by the transmission signal processing unit 308 and transmitted to the receiving communication device 2 via the antenna unit 310.

[0121] Furthermore, in the receiving communication device 2, the RTS frame is analyzed by a frame analysis unit 313. If, as a result of the analysis, the available channel determination unit 305 determines that the channel on which the RTS was transmitted is also available to the receiving communication device 2, it transmits information about the window duration to a frame construction unit 304. The frame construction unit 304 constructs a CTS frame that describes information about the duration of the data to be received, and this frame is processed by a transmission signal processing unit 308 and transmitted to the transmitting communication device 1 via an antenna unit 310. A parameter exchange sequence between the transmitting communication device 1 and the receiving communication device 2, such as the window duration, will be described later.

[0122] Furthermore, depending on the bandwidth of channels that can be used simultaneously, for example, for each 20 MHz bandwidth that is used for simultaneous transmission and reception on multiple channels, the transmitting communication device 1 may include a secondary channel setting unit 307, a transmission signal processing unit 308, an access control unit 309, a received signal detection unit 311, a CCA determination unit 312, and an antenna unit 310. Furthermore, depending on the set number of channel bandwidths that can be detected and used simultaneously, the transmitting communication device 1 may include multiple of the above-mentioned blocks.

[0123] FIG. 15 is another block diagram of the communication device according to the first embodiment.

[0124] FIG. 15 shows an example in which channel transition in this embodiment is applied to a multi-link device.

[0125] A communication device (here, the transmitting communication device 1 will be taken up) 100 mainly comprises a communication unit 110, a control unit 13, and a storage unit 140. The communication unit 110 comprises a communication control unit 111, a communication storage unit 112, a common data processing unit 113, AP1, and AP2. The communication unit 110 can be realized by one or more LSIs.

[0126] AP1 and AP2 each include an individual data processing unit 121, a signal processing unit 122, a wireless interface unit 123, one or more amplifier units 124, and one or more antennas 150. In other words, each AP is configured with a set of the individual data processing unit 121, the signal processing unit 122, the wireless interface unit 123, the amplifier unit 124, and the antenna 150, and two or more APs are components of a communication device.

[0127] AP1 performs processing related to link 1 within AP MLD1, and AP2 performs processing related to link 2 within AP MLD1. In particular, the set of the individual data processing unit 121 and the signal processing unit 122 in each AP is also referred to as an AP entity. Each AP performs communication on its respective link.

[0128] AP1 or the AP entity of AP1 corresponds to a first wireless communication unit that communicates with the communication partner regarding link 1 (first communication), and AP2 or the AP entity of AP2 corresponds to a second wireless communication unit that communicates with the communication partner regarding link 2 (second communication).

[0129] The communication control unit 111 controls the operation of each unit and the transmission of information between each unit. The communication control unit 111 also controls the transfer of control information and management information to be notified to other communication devices 100 to the common data processing unit 113, AP1, and AP2. The communication control unit 111 is also called an MLD management entity.

[0130] The communication storage unit 112 stores information used by the communication control unit 111. The communication storage unit 112 also stores data received from other communication devices.

[0131] During transmission, the common data processing unit 113 performs sequence management of the data stored in the communication storage unit 112 and the control information and management information received from the communication control unit 111, performs encryption processing, etc., and allocates the processed data to each individual data processing unit 121. During reception, the common data processing unit 113 performs data decryption processing and reordering processing. The common data processing unit 113 is also referred to as an AP MLD entity.

[0132] During transmission, each individual data processing unit 121 performs channel access operation based on carrier sense, generates data units by adding a MAC (Media Access Control) header and an error detection code to the data to be transmitted, and performs processing to concatenate multiple data units. During reception, each individual data processing unit 121 performs processing to deconcatenate the MAC header of the received data unit, analyzes and detects errors, and requests retransmission.

[0133] The operations of the common data processing unit 113 and each individual data processing unit 121 are not limited to those described above, and for example, one may perform the operation of the other. The common data processing unit 113 is also called an Upper MAC, Higher MAC, or MLD entity, and the individual data processing unit 121 is also called a Lower MAC.

[0134] During transmission, each signal processing unit 122 performs encoding, interleaving, modulation, etc. on the data unit, adds a physical header, and generates a symbol stream. At this time, each signal processing unit 122 may perform spatial separation processing for MIMO (Multi-Input Multi-Output). However, each signal processing unit 122 may not perform spatial separation processing, but may instead apply an arbitrary delay amount (hereinafter, cyclic shift delay (CSD)) to each antenna 150. During reception, each signal processing unit 122 analyzes the physical header and performs demodulation, deinterleaving, decoding, etc. on the symbol stream to generate a data unit. Furthermore, each signal processing unit 122 estimates complex channel characteristics and performs spatial separation processing as needed.

[0135] During transmission, each wireless interface unit 123 performs digital-to-analog signal conversion, filtering, up-conversion, and phase control on the symbol stream to generate a transmission signal. During reception, each wireless interface unit 123 performs down-conversion, filtering, and analog-to-digital signal conversion on the received signal to generate a symbol stream.

[0136] The amplifier unit 124 of each AP amplifies a signal input from the wireless interface unit 123 or the antenna 150. A part of the amplifier unit 124 may be a component outside the communication unit 110. Alternatively, a part of the amplifier unit 124 may be included in the wireless interface unit 123.

[0137] The control unit 13 controls the communication unit 110 and the communication control unit 111. The control unit 13 may also perform some of the operations of the communication control unit 111. The communication control unit 111 and the control unit 13 may be configured as a single block. The control unit according to the present disclosure corresponds to the communication control unit 111, for example. If the communication control unit 111 and the control unit 13 are configured as a single block, for example, the control unit corresponds to this block. The control unit 13 performs the same operations as the control unit 13 shown in FIGS. 12 and 13. That is, the transmitting communication device 1 performs channel transition operations in AP1 and AP2, respectively, based on the control of the control unit 13.

[0138] The storage unit 140 holds information used by the control unit 13 and the communication unit 110. The storage unit 140 may also perform part of the operations of the communication storage unit 112. The storage unit 140 and the communication storage unit 112 may be configured as a single block.

[0139] Each AP may also include a storage unit. In this embodiment, the frequencies (or frequency bands) of the links used by each AP are different, but the same frequency band may also be used.

[0140] The individual data processing unit 121 and the signal processing unit 122 may be configured as one set, and multiple sets may be connected to one wireless interface unit 123. In other words, one wireless interface unit 123 may be shared by multiple APs.

[0141] Furthermore, a configuration may be adopted in which a wireless interface unit 123, an amplifier unit 124, and an antenna 150 are grouped together, and multiple groups are connected to one signal processing unit 122. In other words, the signal processing unit 122 may be shared by multiple APs. In this case, there may be one or multiple individual data processing units 121.

[0142] FIG. 16 shows an example of a setting state of the window waiting time of the transmitting communication device 1 in the first embodiment.

[0143] Figure 16 shows, for example, a channel arrangement 30 with a bandwidth of 160 MHz used by a network of transmitting and receiving communication devices in the 5 GHz band, a channel arrangement 31 with a bandwidth of 80 MHz used by the transmitting OBSS, and a channel arrangement 32 with a bandwidth of 80 MHz used by the receiving OBSS.The vertical axis is the frequency axis direction, and the trapezoidal parts in the figure represent each channel allocated in the 5 GHz band, representing channels with a bandwidth of 20 MHz, and the straight line extending horizontally from the center indicates the time-dependent progress of operation in that channel.

[0144] In this network, when using a bandwidth of 160 MHz, the transmitting communication device 1 uses the channels set as the primary channel (P20), secondary channel (S20), secondary 40 channel (S40), and secondary 80 channel (S80) in combination to use the bandwidth of 160 MHz.

[0145] 1, each OBSS exists in an overlapping manner on the network of the transmitting communication device 1. For example, in this example, the transmitting OBSS 3 is set to use the lower 80 MHz band of the 160 MHz band of the transmitting communication device 1 in an overlapping manner, and the receiving OBSS 3' is set to use the upper 80 MHz band of the 160 MHz band of the transmitting communication device 1 in an overlapping manner.

[0146] The 20 MHz channels indicated by gray squares in the figure represent the first to fifth access channels, and in this example, the transmitter communication device 1 sets the primary channel (P20) as the first access channel, sets three secondary channels (S20) as the second to fourth access channels, respectively, and sets a 20 MHz channel outside the 5 GHz band as the fifth access channel (denoted here as F20). For the sake of explanation, in Figure 16, the access channels will be described as a first access channel 40, a second access channel 41, a third access channel 42, a fourth access channel 43, and a fifth access channel 44.

[0147] In this example, the transmitting communication device 1 takes into consideration the possibility that all channels used may be occupied by OBSS, and sets the fifth access channel as the final channel, outside the channel band used by the transmitting communication device 1.

[0148] In this example, the second access channel is selected from channels adjacent to the first access channel, which is the primary channel, but the frequencies used for each access channel are not limited to this example. It is sufficient that the first access channel is selected as the primary channel, and at least one of the remaining second to nth access channels is selected from the secondary channels.

[0149] 5, when the first access channel is unavailable, the control unit 13 determines that the channel is unavailable after a predetermined waiting time has elapsed, and performs access control in the order of the second to fifth access channels until a usable channel is found. Also, when the control unit 13 determines that the fifth access channel is unavailable, the control unit 13 controls the transmitting communication device 1 to return to the first access channel and perform access control again.

[0150] The window portion within the dashed line in the figure represents the window waiting time for that channel, and the transmitting communication device 1 waits for the reception of a CTS on each channel along the time axis.

[0151] Therefore, the transmitting communication device 1 is set with a window waiting time in the first access channel, a window waiting time in the second access channel, a window waiting time in the third access channel, a window waiting time in the fourth access channel, and a window waiting time in the fifth access channel, and also has a timing for returning to the first access channel set.

[0152] These settings are exchanged between the sending communication device 1 and the receiving communication device 2 through a parameter exchange sequence, and the transition channel and standby time, etc. are set to the same values ​​between both devices.

[0153] FIG. 17 shows an example of a channel arrangement in the first embodiment.

[0154] FIG. 17 shows an example in which the transmitter communication device 1 performs access control by sequentially switching the access channel in accordance with the setting of the window waiting time for each channel described with reference to FIG.

[0155] Among the operations in the figure, BO indicates backoff operation, PH indicates the processing time of the header including the data frame preamble, RS indicates sending RTS, and CS indicates receiving CTS. Also, RS or CS shown with a solid line indicate that RTS was sent or CTS was received, respectively, while RS or CS shown with a dashed line indicate that RTS was not sent or CTS was not received, respectively.

[0156] When the transmitting communication device 1 performs access control for data transmission, if the transmitting OBSS 3 starts data transmission using the lower 80 MHz bandwidth used by the transmitting communication device 1 before that, the transmitting communication device 1 will be unable to transmit signals on the first access channel 40. In this example, data transmission using the 80 MHz bandwidth by the transmitting OBSS 3 will also prevent data transmission on the second access channel 41.

[0157] In this case, in this embodiment, after a predetermined waiting time has elapsed, the transmitting communication device 1 can transmit an RTS from the third access channel 42, and after receiving a CTS from the receiving communication device 2, can start data transmission.

[0158] On the other hand, if the receiving communication device 2 detects a signal from the overlapping receiving OBSS 3' around it, it will not be able to correctly detect the RTS from the transmitting communication device 1. Furthermore, if the receiving operation of the receiving OBSS 3' sets NAV in the receiving communication device 2 and it is in a virtual carrier sense state, the receiving communication device 2 will not be able to transmit a CTS.

[0159] For example, if the third access channel 42 is unavailable, in the next window the sending communication device 1 will send an RTS on the fourth access channel and then wait to receive a CTS, but the receiving communication device 2 will not be able to return a CTS on this channel.

[0160] By setting at least one access channel from a channel outside the band of the secondary channel, such as the fifth access channel 44, the transmitting communication device 1 and the receiving communication device 2 can transmit RTS and receive CTS between them without being affected by NAV settings by the receiving side's OBSS', etc.

[0161] In this example, after the transmitting communication device 1 transmits an RTS on the fifth access channel 44, which is set as the final channel, the receiving communication device 2 is in standby mode in synchronization with the window period set on this channel, and is therefore able to detect the RTS and transmit a CTS. Upon receiving the CTS, the transmitting communication device 1 can start data transmission on this channel. Hereinafter, the final channel determined by negotiation will also be referred to as the final channel.

[0162] FIG. 18 shows an example of a channel arrangement in a comparative example.

[0163] 18, like FIG. 17, shows a channel allocation 30 of a 160 MHz bandwidth used by the network of a transmitting communication device 1 and a receiving communication device 2 in the 5 GHz band, a channel allocation 31 of an 80 MHz bandwidth used by the transmitting OBSS, and a channel allocation 32 of an 80 MHz bandwidth used by the receiving OBSS, where the vertical axis represents the frequency axis direction and the trapezoidal parts in the figure represent each channel allocated in the 5 GHz band. In the network of the transmitting communication device 1, when using a 160 MHz bandwidth, the transmitting communication device 1 uses a 160 MHz bandwidth by combining channels set as a primary channel (P20), a secondary channel (S20), a secondary 40 channel (S40), and a secondary 80 channel (S80).

[0164] 1, each OBSS overlaps with the network of the transmitting communication device 1. In this example, the transmitting OBSS 3 is set to overlap and use the lower 40 MHz band of the 160 MHz band of the transmitting communication device 1, and the receiving OBSS 3' is set to overlap and use the middle 80 MHz band of the 160 MHz band of the transmitting communication device 1.

[0165] Each OBSS is set to a primary channel (P20), a secondary channel (S20), and a secondary 40 channel (S40). The setting of the primary channel (P20) of the OBSS does not necessarily coincide with or overlap with the setting of the primary channel of the transmitting communication device 1, and considering the bandwidth allocated as a secondary channel, it is highly likely that the primary channel (P20) of the OBSS will be set somewhere among the secondary channels of the transmitting communication device 1. It is also highly likely that the secondary channel (S20) and secondary 40 channel (S40) of the OBSS will be set as the primary channel of the transmitting communication device 1.

[0166] In such a situation, when communication is carried out with a receiving communication device 2 on the primary channel of the transmitting communication device 1, the transmitting OBSS 3 will detect a signal on the secondary channel, and if the communication device of the transmitting OBSS 3 cannot detect use on its own primary channel for a specified backoff time corresponding to the rectangle marked BO in the figure, this OBSS will be able to start OBSS data transmission including the secondary channel.

[0167] On the other hand, the communication device of the receiving side OBSS 3' also cannot detect use on the primary channel that it has set, and so OBSS data transmission begins.

[0168] Furthermore, if the receiving communication device 2 detects a transmission signal from the receiving side OBSS 3', it will experience interference in receiving data addressed to itself, but at the same time, if the transmitting communication device 1 cannot detect a transmission signal from this OBSS, it will end up transmitting unnecessary data.

[0169] In addition, in the comparative example, the frequency channels indicated by dashed lines are not in use and do not receive or cause interference, but since no access channels are set, these channels cannot be used between the transmitting communication device 1 and the receiving communication device 2.

[0170] FIG. 19 shows an example of an association operation of a communication device in the first embodiment.

[0171] In this example, an association operation between an access point (AP) and a communication terminal (STA) will be described as a communication device. When performing an association operation, the access point (AP) and the communication terminal (STA) may exchange settings regarding whether or not to enable a function for performing a channel transition operation of the first to nth access channels described in this embodiment.

[0172] For example, when a new communication terminal (STA) joins the network, the access point (AP) sends a specific beacon to the communication terminal (STA) indicating whether or not this function can be configured, by adding the corresponding information element.

[0173] The communication terminal (STA) that receives the beacon then sends an association request to the access point (AP), and after receiving an association response from the access point (AP), joins the network (BSS).

[0174] Furthermore, even if an information element is not added to a beacon, the access point (AP) may be configured to add this information element to an association response and notify it.

[0175] Furthermore, when the access point (AP) and the communication terminal (STA) enable channel transition operations among the first to n-th access channels, the operation is started after parameter exchange, which will be described later.

[0176] FIG. 20 shows an example of parameter exchange for channel transition operation in the first embodiment.

[0177] In this example, the communication devices are a sending communication device 1 and a receiving communication device 2, and the operation of setting parameters is shown, in which negotiation is performed by exchanging information elements, which are signals indicating parameter setting information.

[0178] This parameter exchange can be performed using a flow similar to that for parameter exchange for secondary channel access. For example, to request the setting of secondary channel access, the transmitting communication device 1 transmits information elements describing the parameters of the primary channel, the secondary channel, and their durations as a secondary channel access request. Furthermore, if a channel is selected from outside the band of the primary channel and the secondary channel, the parameters of this channel and its duration are also described in the information element.

[0179] Upon receiving this request, the receiving communication device 2 acquires the parameters described in the information element, calculates the parameters of the secondary channel that can be set and its duration, and transmits a secondary channel access response that describes these parameters. If the response depends on the requested parameters, the receiving communication device 2 may return the parameters as they are. After receiving the response, the transmitting communication device 1 acquires the parameters and sets them as transmission parameters for the secondary channel, etc.

[0180] Furthermore, the transmitting communication device 1 transmits a secondary channel access grant to notify the receiving communication device 2 that it has accepted the set parameters. Upon receiving the grant, the receiving communication device 2 acquires the parameters and sets them as reception parameters for the secondary channel, etc.

[0181] FIG. 21 shows an example of information elements when setting parameters for a communication device in the first embodiment.

[0182] The information element in this embodiment is configured to set a request message, a response message, or a grant message as needed.

[0183] 21 , the information element includes an Element Type indicating a predetermined element format, a Length indicating the information length of the information element, and a Frame Type indicating the frame format. In this embodiment, the bandwidth of the second to nth access channels is set to 20 MHz, but the information element may also include a Bandwidth indicating the bandwidth of the second to nth access channels so that other bandwidths can be set.

[0184] The information element also includes Ch. Counts, which indicates the number of channels to be set, and Ch. List, which indicates a list of the access channels to be set. Ch. List lists the first to n-th channels in the order of channel transition. In this example, the first to fourth access channels are listed in order as the order of channel transition. As described above, the second and subsequent access channels include at least one secondary access channel, so Ch. List lists at least one secondary channel.

[0185] The transmitting communication device 1 and the receiving communication device 2 negotiate with each other through a parameter exchange sequence and share a Ch.List to determine the order of channel transitions.

[0186] When one channel is set outside the band as the final channel, the information element may include "Final Ch.", which indicates information about the final channel. Furthermore, without being limited to this example, the final channel may be written in the Ch. List.

[0187] The information element also includes an Available Ch Bitmap in which other available channels are described in bitmap format.

[0188] The information element also includes, as window parameters indicating the duration of the window set for each channel, parameters such as Target MCS indicating information on the MCS used for communication with the communication partner, Access Category indicating the EDCA access category, CWmin MAX indicating the maximum initial value of the contention window, Primary Windows indicating the window duration of the primary channel, Non-Primary Windows indicating the window duration of the second access channel and subsequent access channels of non-primary channels, and Fast Window indicating that the window has been set at an earlier timing than the specified window duration.

[0189] Furthermore, the parameters exchanged between the transmitting communication device 1 and the receiving communication device 2 are not limited to these. The information elements may include only the Ch. List and the Window Parameter, or the Window Parameter may be transmitted as a separate information element. For example, in a smaller system configuration where channel transitions are performed using two channels, a first access channel and a second access channel, the Ch. List may include the 1st Access Ch. and the 2nd Access Ch. Furthermore, the Window Parameter may include Primary Windows and Non-Primary Windows as information elements.

[0190] FIG. 22 is an example of a flowchart when the transmitter communication device 1 in the first embodiment performs access control.

[0191] In this example, two channels (n=2) are set as access channels in the transmitting communication device 1, and the first access channel is set as the primary channel, and the second access channel is set as the secondary channel as the final channel.

[0192] In step S101, the control unit 13 sets the primary channel (P20) as the first access channel based on information managed by the channel management unit 303. In step S102, the control unit 13 controls the primary channel setting unit 306 to set the window duration of the first access channel from information described in Primary Windows of Window Parameter among information elements exchanged with the receiving communication device 2.

[0193] In step S103, the control unit 13 controls the primary channel setting unit 306 to calculate the timing of the random backoff time and set the timing at which data such as RTS can be transmitted. In step S104, the control unit 13 controls the primary channel setting unit 306 to determine whether NAV is set for the first access channel.

[0194] If the NAV setting is set for the first access channel (YES in step S104), in step S106, the control unit 13 repeats the determination operations of steps S104 and S106 until the duration of the window expires. If the NAV setting is not set for the first access channel (NO in step S104), in step S105, the control unit 13 controls the CCA determination unit 312 to determine whether a signal exceeding a predetermined detection threshold has been detected as a CCA.

[0195] If a signal exceeding the CCA detection threshold is detected (YES in step S105), the control unit 13 returns to step S106 and repeats the operation until the duration of the window corresponding to the Primary Windows or Non-Primary Windows of the Window Parameter expires.

[0196] If a signal exceeding the CCA detection threshold is not detected until the backoff time set by the transmitting communication device as an access control parameter has elapsed (NO in step S105), in step S110, the control unit 13 transmits an RTS to the receiving communication device 2 based on the access control by the access control unit 309. Thereafter, the control unit 13 controls the received signal detection unit 311 to wait for reception of a CTS.

[0197] In step S111, the control unit 13 controls the received signal detection unit 311 to wait for the reception of a CTS during the duration of the window of the primary channel. If a CTS is received (YES in step S111), in step S112, the control unit determines that the primary channel is available and sets the available time for that channel as a TXOP (Transmission Opportunity) under the control of the access control unit 309.

[0198] In step S113, the control unit 13 controls the frame construction unit 304 to construct an A-MPDU (aggregation MAC protocol data unit) data frame for the duration of the TXOP. In step S114, the control unit 13 controls the transmission signal processing unit 308 to perform transmission signal processing on the constructed A-MPDU data frame and transmit it to the receiving communication device 2 via the antenna unit 310.

[0199] On the other hand, if a CTS is not received before the window duration expires (NO in step S111), the control unit 13 determines in step S107 that the access channel is unavailable and controls the secondary channel setting unit 307 to set the next channel, the second access channel, by referring to the channel information written in the Ch. Lists. In step S108, the secondary channel setting unit 307 also sets the window duration of the second access channel based on the information written in the Non-Primary Windows of the Window Parameter.

[0200] Similarly, if the window duration of the first access channel expires in step S106, the control unit 13 sets a channel to be the next channel, the second access channel, in step S107. If the window duration expires, the control unit 13 also sets the second access channel as the access channel in cooperation with both devices, in conjunction with the expiration of the window duration of the receiving communication device 2.

[0201] In other words, please note that the random backoff time set by the sender is set as the maximum value of the contention window CWmin, so it is necessary to prevent the receiver from transitioning to another secondary channel before the window duration known to the receiver expires.

[0202] In step S109, the control unit 13 controls the secondary channel setting unit 307, and if there is a description of the secondary channel and final channel to which the channel to be transitioned is to be listed in the Ch. Lists (NO in step S109), the control unit 13 transitions to the channel listed in the Ch. Lists, and returns to step S104 to determine whether the secondary channel setting unit 307 has set NAV to the new second access channel.

[0203] The operations of the subsequent steps S105 to S106 and steps S110 to S114 are the same as those described above, and therefore will not be described again. In other words, when the control unit 13 receives a CTS on the second access channel, data transmission becomes possible after setting the TXOP.

[0204] On the other hand, if CTS is not received on the second access channel in step S111 (NO in step S111), the control unit 13 sets the second access channel as the secondary channel again in step S107, and sets the window duration of the second access channel in step S108. In step S109, if there is no secondary channel or final channel to which a transition should be made as a channel listed in the Ch. Lists (NO in step S109), the process returns to S101 and access control is performed on the first access channel. Note that the operation of step S109 may be performed after the operation of NO in step S111 or after the operation of YES in step S106.

[0205] FIG. 23 is an example of a flowchart when the recipient communication device 2 in the first embodiment performs reception control.

[0206] In this example, as in the example of Figure 22, two channels are set as access channels in the receiving communication device 2 (n = 2), and the first access channel is set as the primary channel and the second access channel is set as the secondary channel.

[0207] In step S201, the control unit 13 sets the primary channel (P20) as the first access channel based on information managed by the channel management unit 303. In step S202, the control unit 13 controls the primary channel setting unit 306 to set the window duration of the first access channel from the information described in the Primary Windows field of the Window Parameter among the information elements exchanged with the transmitting communication device 1.

[0208] In step S203, the control unit 13 controls the primary channel setting unit 306 to determine whether the timing to start access control has arrived in the transmitting communication device 1, for example, when communication with the access point has ended, when the start timing of the R-TWT service period has arrived, etc. If the timing to start access control has not arrived (NO in step S203), the control unit 13 waits until the timing to start access control arrives.

[0209] When the timing to start access control arrives (YES in step S203), in step S204, the control unit 13 controls the CCA determination unit 312 to determine whether a CCA signal exceeding a predetermined detection threshold has been detected. If a CCA signal exceeding the predetermined detection threshold has not been detected (NO in step S204), the control unit 13 controls the CCA determination unit 312 to continue the determination until a signal exceeding the detection threshold is received.

[0210] If a signal exceeding the detection threshold is detected (YES in step S204), in step S205, the control unit 13 controls the received signal detection unit 311 and the frame analysis unit 313 to determine whether or not an RTS addressed to itself has been detected. If an RTS addressed to itself has been detected (YES in step S205), in step S206, the control unit 13 controls the NAV setting unit 314 to refer to the NAV setting status of this channel.

[0211] In step S207, the control unit 13 controls the NAV setting unit 314 to determine whether the first access channel is available based on the NAV setting status. If the NAV is set, the control unit 13 determines that the first access channel is unavailable (YES in step S207), and the process returns to step S204, where the control unit 13 again determines whether a signal exceeding the detection threshold for CCA has been detected.

[0212] If NAV setting is not performed and the control unit 13 determines that the first access channel is in use (YES in step S207), in step S208, the control unit 13 controls the primary channel setting unit 306 to, for example, calculate the available duration by back-calculating the time until the receiving side OBSS 3' starts transmitting the R-TWT scheduled for the first access channel. In step S209, the control unit 13 controls the access control unit 309 to transmit a CTS. After transmitting the CTS, the process returns to step S204, and the control unit 13 again determines whether a signal exceeding the detection threshold for CCA has been detected in order to start receiving data in the first access channel.

[0213] Furthermore, if no RTS addressed to itself is detected (NO in step S205), in step S210, the control unit 13 controls the received signal detection unit 311 and frame analysis unit 313 to determine whether data addressed to itself has been received. If the received data is data addressed to itself (YES in step S210), in step S211, the control unit 13 controls the received signal detection unit 311 and frame analysis unit 313 to start data reception processing. The received data may be stored in the reception buffer 315. After the data reception processing is completed, the control unit 13 ends the processing. Note that, if necessary, in the data reception processing, the control unit 13 may exchange block ACKs, request and receive retransmissions, etc. with the transmitting communication device 1.

[0214] On the other hand, if the received data is not addressed to itself, the data is addressed to another surrounding communication device, such as the receiving-side OBSS 3'. If the received data is not addressed to itself (NO in step S210), in step S212, the control unit 13 controls the frame analysis unit 313 to perform frame analysis of the received data and detect header information. In step S213, the control unit 13 acquires information such as the Duration of the MAC header using the frame analysis unit 313.

[0215] In step S214, the control unit 13 controls the frame analysis unit 313 to determine whether the analyzed data is a CTS frame or a data frame (NAV-related frame) addressed to another communication device. If the analyzed data is a NAV-related frame addressed to another communication device (YES in step S214), in step S215, the control unit 13 controls the NAV setting unit 314 to set the NAV until the timing described in the Duration information. After setting the NAV, the process returns to step S204, and the control unit 13 again determines whether a signal exceeding the detection threshold for CCA has been detected.

[0216] If the analyzed data is not a NAV-related frame addressed to another communication device (NO in step S214), in step S216, the control unit 13 controls the primary channel setting unit 306 to determine whether the duration of the window of the first access channel has expired. If the duration of the window has not expired (NO in step S216), the control unit 213 returns to step S203 to continue waiting for reception until the window expires, and controls the primary channel setting unit 306 to again determine whether the timing to start access control has arrived.

[0217] If the window duration has expired (YES in step S216), the control unit 13 determines that the channel is unavailable and controls the secondary channel setting unit 307 to set a channel to be the next channel, the second access channel. In step S218, the control unit 13 controls the secondary channel setting unit 307 to set the window duration of the second access channel based on the information described in the Non-Primary Windows of the Window Parameter.

[0218] In step S219, the control unit 13 controls the secondary channel setting unit 307, and if there is a description of the secondary channel and final channel to which the channel should be transitioned as listed in the Ch. Lists (NO in step S219), the control unit 13 returns to step S203, controls the secondary channel setting unit 307, and again determines whether the timing to start access control has arrived.

[0219] The operations of the subsequent steps S204 to S218 are the same as those described above, and therefore will not be described again. That is, when the control unit 13 transmits a CTS from the second access channel, it becomes possible to receive data thereafter.

[0220] On the other hand, if the window duration of the second access channel has expired in step S216, the control unit 13 sets the second access channel as the secondary channel again in step S217, and sets the window duration of the second access channel in step S218. In step S219, if there is no secondary channel or final channel to which the channel to be transitioned as a channel listed in the Ch. Lists is to be established (NO in step S219), the control unit 13 returns to step S201 and performs access control on the first access channel. Note that the operation of step S219 may be performed after the operation of step S216 (YES).

[0221] In addition, in the network of the receiving communication device 2, when the beacon transmission timing arrives or the R-TWT service period arrives, access control is carried out from the beginning, so the receiving communication device 2 is configured to proceed to step S203 and determine whether these timings have arrived.

[0222] According to this embodiment, a communication device defines multiple channels as access channels at frequencies other than the primary channel, such as secondary channels, with a predetermined order for performing access control, and can therefore carry out low-latency data transmission using these channels even when the primary channel is unavailable.

[0223] Furthermore, according to this embodiment, the communication device can identify channels that are available not only to the transmitting side but also to the receiving side by exchanging frames of the first signal and the second signal in advance before data transmission on the transitioned channel, thereby ensuring reliable data transmission.

[0224] Furthermore, according to this embodiment, even if the channels experiencing interference on the transmitting and receiving sides are different, the communication device can transmit data if the channels available to both communication devices match.

[0225] Furthermore, according to this embodiment, the communication device can reliably carry out data transmission by selecting an access channel from outside the band of the secondary channel, even if the bands of the primary channel and secondary channel are occupied by OBSS or the like.

[0226] Second Embodiment FIG. 24 shows an example of the time transition of each channel used by the transmitting communication device 1 of the second embodiment.

[0227] The overall configuration of the transmitting communication device 1 is the same as that of Figures 13 and 14, and therefore a description thereof will be omitted. In this embodiment, the transmitting communication device 1 will be described assuming that first to fifth access channels are set in advance as access channels.

[0228] In the figure, the dashed lines indicate the window duration of each channel, and the diamonds in the first access channel indicate the presence of multiple slots in the contention window during the random backoff time. TS indicates the training sequence. The gray areas before and after the window duration indicate the time required for channel transitions.

[0229] In this embodiment, when a channel transition operation is realized in a communication device, the operation of the communication device will be described, including the time required for channel transition that occurs due to circuit switching, etc. In the example of Fig. 24, the switching time for each channel is shown as a time transition, but the transition does not necessarily have to occur at this timing, and the circuit within the communication device may be configured to perform the same operation.

[0230] As described above, in order to take into account the time required for channel transitions caused by circuit switching or the like, the communication device starts a channel transition operation for the pre-transition channel under the control of the control unit 13 before the end of the window waiting time. Furthermore, the time required for the channel transition occurs for both the pre-transition channel and the post-transition channel. Therefore, the communication device also starts a channel transition for the post-transition channel under the control of the control unit 13 before the start of the window waiting time. In this diagram, the transmitting communication device 1 starts a channel transition just before the end of the first access channel, which is the first channel transition under the control of the control unit 13, and starts a channel transition operation for the second access channel, which is the post-transition channel, before the start of the window. Furthermore, in this example, the control unit 13 completes the channel transition operation for the second access channel before the start of the window waiting time.

[0231] In other words, for the nth access channel, the communication device starts the channel transition operation from the n-1th access channel before the start of the window waiting time, and starts the channel transition operation to the n+1th access channel before the end of the window waiting time.

[0232] It is desirable for the communication device to complete the channel transition before the start of the window duration in the nth access channel.

[0233] In the first access channel, access control including a predetermined random backoff time is performed, and the transmitting communication device 1 can transmit a signal after the random backoff time has expired. In this example, the transmitting communication device 1 starts transmitting a training sequence after the random backoff time. When the receiving communication device 2 detects the training signal, it performs decryption processing of the data portion on that channel.

[0234] On the other hand, if the first access channel is unavailable, the transmitting communication device 1 may detect the state of that channel until the window duration expires, and if it becomes available by the time the window duration expires, may use that channel to transmit the training sequence.

[0235] If the first access channel is unavailable, the transmitting communication device 1 switches to the second access channel before the window duration expires. That is, under the control of the control unit 13, the transmitting communication device 1 switches the frequency to the second access channel in the portion indicated by the dashed line in the figure, and controls the circuit so that operation is stable at the start of the window of the second access channel.

[0236] Similarly, for the second to fifth access channels, the transmitting communication device 1 controls the circuit so that operation in each access channel is stabilized at the start of the window for that channel under the control of the control unit 13. For the fifth access channel, which is the final channel, the transmitting communication device 1 performs an operation to switch to the first access channel before the end of the window waiting time under the control of the control unit 13. At this time, for the first access channel, the transmitting communication device 1 controls the circuit so that operation is stabilized at the start of the window under the control of the control unit 13.

[0237] According to this embodiment, when controlling channels, the communication device starts a channel transition operation from the (n-1)th access channel before the start of the waiting time of the window, and starts a channel transition operation to the (n+1)th access channel before the end of the waiting time of the window, thereby stabilizing the operation of each channel at the start of the window.

[0238] <Example of Computer Configuration> The above-described series of processes can be executed by hardware or software. When the series of processes is executed by software, the program constituting the software is installed from a program recording medium into a computer incorporated in dedicated hardware, or into a general-purpose personal computer, etc.

[0239] FIG. 25 is a block diagram showing an example of the hardware configuration of a computer that executes the above-described series of processes by a program.

[0240] A CPU (Central Processing Unit) 801 , a ROM (Read Only Memory) 802 , and a RAM (Random Access Memory) 803 are interconnected by a bus 804 .

[0241] An input / output interface 805 is also connected to the bus 804. An input unit 806 including a keyboard, a mouse, etc., and an output unit 807 including a display, a speaker, etc. are connected to the input / output interface 805. In addition, a storage unit 808 including a hard disk, a nonvolatile memory, etc., a communication unit 809 including a network interface, etc., and a drive 810 that drives removable media 811 are also connected to the input / output interface 805.

[0242] In a computer configured as described above, the CPU 801 performs the above-described series of processes by, for example, loading a program stored in the storage unit 808 into the RAM 803 via the input / output interface 805 and the bus 804 and executing it.

[0243] The program executed by the CPU 801 is provided, for example, by being recorded on a removable medium 811 or via a wired or wireless transmission medium such as a local area network, the Internet, or digital broadcasting, and is installed in the storage unit 808.

[0244] The program executed by the computer may be a program that processes in chronological order according to the order described in this specification, or may be a program that processes in parallel or at the required timing, such as when called.

[0245] <Application Examples> The present technology can be applied to various products. For example, the communication device 100 in Figures 13 and 14 may be realized as a mobile terminal such as a smartphone, a tablet PC (Personal Computer), a notebook PC, a portable game terminal, or a digital camera; a fixed terminal such as a television receiver, a projector, a printer, a digital scanner, or a network storage; or an in-vehicle terminal such as a car navigation system. Furthermore, the communication device 100 may be realized as an M2M (Machine-to-Machine Communication) terminal such as a smart meter, a vending machine, a remote monitoring device, or a POS (Point-of-Sale) terminal. Furthermore, the communication device 100 may be a wireless communication module (e.g., an integrated circuit module configured on a single die) mounted on such a terminal.

[0246] On the other hand, for example, the communication device 100 may be realized as a wireless LAN AP (wireless base station) with or without a router function. The communication device 100 may also be realized as a mobile wireless LAN router. Furthermore, the communication device 100 may be a wireless communication module (for example, an integrated circuit module configured on a single die) mounted on these devices.

[0247] <Configuration Example of Smartphone> FIG. 26 is a block diagram showing a schematic configuration example of a smartphone to which the present technology is applied.

[0248] The smartphone 900 includes a processor 901, a memory 902, a storage 903, an external connection interface 904, a camera 906, a sensor 907, a microphone 908, an input device 909, and a display device 910. The smartphone 900 also includes a speaker 911, a wireless communication interface 913, an antenna switch 914, an antenna 915, a bus 917, a battery 918, and an auxiliary controller 919.

[0249] The processor 901 may be, for example, a CPU or a SoC (System on Chip), and limits the functions of the application layer and other layers of the smartphone 900.

[0250] The memory 902 includes RAM and ROM, and stores programs and data executed by the processor 901 .

[0251] The storage 903 includes a storage medium such as a semiconductor memory or a hard disk.

[0252] The external connection interface 904 is an interface for connecting an external device such as a memory card or a USB (Universal Serial Bus) device to the smartphone 900 .

[0253] The camera 906 has an imaging element such as a charge coupled device (CCD) or a complementary metal oxide semiconductor (CMOS), and generates a captured image.

[0254] The sensor 907 includes a group of sensors such as a positioning sensor, a gyro sensor, a geomagnetic sensor, and an acceleration sensor.

[0255] The microphone 908 converts the sound input to the smartphone 900 into an audio signal.

[0256] The input device 909 includes, for example, a touch sensor that detects a touch on the screen of the display device 910, a keypad, a keyboard, a button, or a switch, and accepts operations or information input from the user.

[0257] The display device 910 has a screen such as a liquid crystal display (LCD) or an organic light-emitting diode (OLED) display, and displays an output image from the smartphone 900. The display device 910 may also be configured as a projector that projects the output image onto a screen. The speaker 911 converts an audio signal output from the smartphone 900 into audio. The processor 901 also controls the display on the display device 910 based on information received via the first link or the second link and the user's operation of the input device 909.

[0258] The wireless communication interface 913 supports one or more wireless LAN standards such as IEEE802.11a, 11b, 11g, 11ac, 11ad, 11ax, 11ay, and 11be, and performs wireless communication.

[0259] The wireless communication interface 913 communicates with other devices via a wireless LAN AP in infrastructure mode, and directly with other devices in ad hoc mode or a direct communication mode such as Wi-Fi Direct.

[0260] Unlike ad hoc mode, in Wi-Fi Direct, one of the two terminals acts as an AP, but communication is carried out directly between the terminals.

[0261] The wireless communication interface 913 typically includes a baseband processor, an RF (Radio Frequency) circuit, a power amplifier, etc. The wireless communication interface 913 may be a one-chip module that integrates a memory that stores a communication control program, a processor that executes the program, and related circuits.

[0262] The wireless communication interface 913 may support other types of wireless communication methods, such as a short-range wireless communication method, a proximity wireless communication method, or a cellular communication method, in addition to a wireless LAN method.

[0263] The antenna switch 914 switches the connection destination of the antenna 915 between multiple circuits (for example, circuits for different wireless communication methods) included in the wireless communication interface 913 .

[0264] The antenna 915 has a single or multiple antenna elements (e.g., multiple antenna elements constituting a MIMO (Multiple Input Multiple Output) antenna) and is used for transmitting and receiving wireless signals via the wireless communication interface 913. For example, when the antenna 915 has multiple antenna elements, it has a first antenna element and a second antenna element to constitute a MIMO antenna. Furthermore, multiple antennas 915 may be provided, and when the multiple antennas 915 include a first antenna and a second antenna, they may communicate via a first link and a second link, respectively.

[0265] 26 , the smartphone 900 may include multiple antennas (for example, an antenna for wireless LAN and an antenna for a close-proximity wireless communication system). In this case, the antenna switch 914 may be omitted from the configuration of the smartphone 900.

[0266] The bus 917 connects the processor 901, memory 902, storage 903, external connection interface 904, camera 906, sensor 907, microphone 908, input device 909, display device 910, speaker 911, wireless communication interface 913, and auxiliary controller 919 to each other.

[0267] The battery 918 supplies power to each block of the smartphone 900 shown in Fig. 26 via a power supply line partially indicated by a dashed line in the figure. The auxiliary controller 919 operates the minimum necessary functions of the smartphone 900, for example, in sleep mode.

[0268] 26, for example, the control unit 13 and the wireless communication unit 15 in FIG. 13 may be implemented in the wireless communication interface 913. Furthermore, at least some of these functions may be implemented in the processor 901 or the auxiliary controller 919.

[0269] The smartphone 900 may operate as a wireless AP (software AP) by the processor 901 executing an AP function at the application level. The wireless communication interface 913 may also have a wireless AP function.

[0270] Furthermore, the smartphone 900 may be provided with a biometric authentication unit (fingerprint authentication, palm shape authentication, voice authentication, blood vessel authentication, face authentication, iris authentication, retina authentication). In this case, a wireless communication interface 913 in which the control unit 13 and the wireless communication unit 15 in Fig. 13 are implemented is configured to receive power from the same battery 918 as at least one of the display device 910, the speaker 911, and the biometric authentication unit.

[0271] Furthermore, in the smartphone 900, information is displayed on at least one of the display device 910 and the speaker 911 based on communication with an external device via the wireless communication interface 913. At this time, information relating to the present technology may be output from at least one of the display device 910 and the speaker 911.

[0272] <Configuration Example of In-Vehicle Device> FIG. 27 is a block diagram showing an example of a schematic configuration of an in-vehicle device 920 to which the present technology is applied.

[0273] The in-vehicle device 920 is configured to include a processor 921, a memory 922, a GNSS (Global Navigation Satellite System) module 924, a sensor 925, a data interface 926, a content player 927, and a storage medium interface 928. The in-vehicle device 920 is also configured to include an input device 929, a display device 930, a speaker 931, a wireless communication interface 933, an antenna switch 934, an antenna 935, and a battery 938.

[0274] The processor 921 may be, for example, a CPU or an SoC, and controls the navigation function and other functions of the in-vehicle device 920. The processor 921 can also control the vehicle's driving system, such as the brake, accelerator, or steering, based on information obtained through communication based on the present technology.

[0275] The memory 922 includes RAM and ROM, and stores programs and data executed by the processor 921 .

[0276] The GNSS module 924 measures the position (e.g., latitude, longitude, and altitude) of the in-vehicle device 920 using GNSS signals received from GNSS satellites.

[0277] The sensor 925 includes a group of sensors such as a gyro sensor, a geomagnetic sensor, and an air pressure sensor.

[0278] The data interface 926 is connected to an in-vehicle network 941 via a terminal (not shown), for example, and acquires data generated on the vehicle side, such as in-vehicle data.

[0279] The content player 927 plays content stored on a storage medium (e.g., a CD or DVD) inserted into the storage medium interface 928. The storage medium interface 928 is an example of an external connection interface, and the storage medium is an example of an external storage medium.

[0280] The input device 929 includes, for example, a touch sensor that detects a touch on the screen of the display device 930, a button, or a switch, and accepts operations or information input from the user.

[0281] The display device 930 has a screen such as an LCD or OLED display, and displays information such as navigation functions or images of content being played, etc. The processor 921 also controls the display of the display device 930 based on information received via the first link or the second link and the user's operation of the input device 929.

[0282] The speaker 931 outputs the audio of the navigation function or the content being played.

[0283] Note that the navigation function and the function of the content player 927 are optional in the in-vehicle device 920. The navigation function and the content player 927 may be removed from the configuration of the in-vehicle device 920.

[0284] The wireless communication interface 933 supports one or more wireless LAN standards such as IEEE 802.11a, 11b, 11g, 11n, 11ac, 11ad, 11ax, 11ay, and 11be, and performs wireless communication. The wireless communication interface 933 communicates with other devices via a wireless LAN AP in infrastructure mode. The wireless communication interface 933 also communicates directly with other devices in ad hoc mode or a direct communication mode such as Wi-Fi Direct.

[0285] The wireless communication interface 933 typically includes a baseband processor, an RF circuit, a power amplifier, etc. The wireless communication interface 933 may be a one-chip module that integrates a memory that stores a communication control program, a processor that executes the program, and related circuits. In addition to the wireless LAN system, the wireless communication interface 933 may support other types of wireless communication systems, such as a short-range wireless communication system, a proximity wireless communication system, or a cellular communication system.

[0286] The antenna switch 934 switches the connection destination of the antenna 935 among multiple circuits included in the wireless communication interface 933 .

[0287] The antenna 935 has a single or multiple antenna elements and is used for transmitting and receiving wireless signals via the wireless communication interface 933. For example, when the antenna 935 has multiple antenna elements, it may have a second antenna element in addition to a first antenna element to form a MIMO antenna.

[0288] 27, the in-vehicle device 920 may include a plurality of antennas 935. In that case, the antenna switch 934 may be omitted from the configuration of the in-vehicle device 920.

[0289] In the in-vehicle device 920 shown in FIG. 27 , the battery 938 is connected via a power supply line partially indicated by a dashed line in the figure. For example, the control unit 13 and the wireless communication unit 15 in FIG. 27 may be implemented in the wireless communication interface 933. Furthermore, at least some of these functions may be implemented in the processor 921. The battery 938 is an example of a power sharing unit. The power sharing unit supplies power to the control unit 13, the processor 921, the input device 929, the display device 930, and the first and second antenna elements.

[0290] The wireless communication interface 933 may also operate as the communication device described above and provide wireless connection to a terminal carried by a user in the vehicle.

[0291] Moreover, the present technology may be realized as an in-vehicle system (or vehicle) 940 including one or more blocks of the above-described in-vehicle device 920, an in-vehicle network 941, and a vehicle-side module 942. The vehicle-side module 942 generates vehicle-side data such as vehicle speed, engine rotation speed, or failure information, and outputs the generated data to the in-vehicle network 941.

[0292] <Configuration Example of Wireless AP> FIG. 28 is a block diagram showing an example of a schematic configuration of a wireless AP 950 to which the present technology is applied.

[0293] The wireless AP 950 includes a controller 951 , a memory 952 , an input device 954 , a display device 955 , a network interface 957 , a wireless communication interface 963 , an antenna switch 964 , and an antenna 965 .

[0294] The controller 951 may be, for example, a CPU or a DSP (Digital Signal processor) and operates various functions of the IP (Internet Protocol) layer and higher layers of the wireless AP 950 (e.g., access restriction, routing, encryption, firewall, and log management).

[0295] The memory 952 includes RAM and ROM, and stores programs executed by the controller 951 and various control information (for example, a terminal list, a routing table, an encryption key, security settings, and logs).

[0296] The input device 954 includes, for example, buttons and switches, and receives operations from the user.

[0297] The display device 955 includes an LED lamp or the like and displays information such as the operating status of the wireless AP 950. The display device 955 may also be configured as a projector that projects an output image onto a screen. A processor (not shown) controls the display on the display device 955 based on information received via the first link or the second link and a user's operation of the input device 954. The processor may also be implemented within the controller 951.

[0298] The network interface 957 is a wired communication interface for connecting the wireless AP 950 to a wired communication network 958. The network interface 957 may have multiple connection terminals. The wired communication network 958 may be a LAN such as Ethernet (registered trademark) or a WAN (Wide Area Network).

[0299] The wireless communication interface 963 supports one or more wireless LAN standards such as IEEE802.11a, 11b, 11g, 11n, 11ac, 11ad, 11ax, 11ay, and 11be, and provides wireless connection to nearby terminals as an AP.

[0300] The wireless communication interface 963 typically includes a baseband processor, an RF circuit, a power amplifier, and the like.

[0301] The wireless communication interface 963 may be a one-chip module that integrates a memory that stores a communication control program, a processor that executes the program, and related circuits.

[0302] The antenna switch 964 switches the connection destination of the antenna 965 among multiple circuits included in the wireless communication interface 963. The antenna 965 has a single antenna element or multiple antenna elements and is used for transmitting and receiving wireless signals via the wireless communication interface 963. For example, when the antenna 965 has multiple antenna elements, it has a second antenna element in addition to a first antenna element.

[0303] 28, for example, the control unit 13 and the wireless communication unit 15 in FIG. 13 may also be implemented in the wireless communication interface 963. Furthermore, at least a part of these functions may be implemented in the controller 951.

[0304] The above-described embodiment shows an example for realizing the present technology, and the matters in the embodiment correspond to the matters specifying the invention in the claims. Similarly, the matters specifying the invention in the claims correspond to the matters in the embodiment of the present technology having the same title. However, the present technology is not limited to the embodiment, and can be realized by applying various modifications to the embodiment without departing from the gist of the present technology.

[0305] Furthermore, the processing procedures described in the above embodiments may be regarded as a method having a series of these procedures, or as a program for causing this computer to execute these procedures or a recording medium for storing that program.

[0306] Examples of the recording medium that can be used include a CD (Compact Disc), an MD (MiniDisc), a DVD (Digital Versatile Disc), a memory card, and a Blu-ray (registered trademark) Disc.

[0307] In this specification, a system refers to a collection of multiple components (devices, modules (components), etc.), regardless of whether all of the components are contained in the same housing. Therefore, multiple devices housed in separate housings and connected via a network, and a single device housed in a single housing with multiple modules, are both systems.

[0308] Furthermore, the effects described in this specification are merely examples and are not limiting, and other effects may also be present.

[0309] The embodiments of the present technology are not limited to the above-described embodiments, and various modifications are possible without departing from the spirit of the present technology.

[0310] For example, the present technology can be configured as a cloud computing system in which a single function is shared and processed collaboratively by a plurality of devices via a network.

[0311] Furthermore, each step described in the above flowchart can be executed by one device, or can be shared and executed by a plurality of devices.

[0312] Furthermore, when one step includes multiple processes, the multiple processes included in that one step can be executed by one device or can be shared and executed by multiple devices.

[0313] This embodiment may also have the following configuration. [Notes] [Item 1] A communication device including a control unit that controls a wireless communication unit that performs wireless communication with another communication device using first to n-th access channels (n is an integer of 2 or greater), wherein the control unit: performs access control on a first access channel set as a primary channel; and, based on a situation in which it is determined that the first access channel is unavailable, performs the access control on a second access channel set other than the primary channel. [Item 2] The communication device according to item 1, wherein the control unit sequentially performs the access control on the second to n-th access channels until an available channel is found. [Item 3] The communication device according to any one of items 1 to 2, wherein the control unit performs the access control on the first access channel when it is determined that the n-th access channel is unavailable. [Item 4] The communication device according to any one of items 1 to 3, wherein at least one of the channels from the second to n-th access channels is selected from a frequency band set as a secondary channel. [Item 5] The communication device according to any one of items 1 to 4, wherein at least one of the channels from the second access channel to the nth access channel is selected from a frequency band other than a predetermined frequency band set as a primary channel and a secondary channel. [Item 6] The communication device according to any one of items 1 to 5, wherein the control unit determines that the first access channel is unavailable after a predetermined waiting time has elapsed and performs the access control using the second access channel. [Item 7] The communication device according to item 6, wherein the predetermined waiting time in the first access channel includes a random backoff time, and the control unit controls to transmit a first signal indicating a request to start communication or to use a channel after the random backoff time has elapsed. [Item 8] The communication device according to item 7, wherein the control unit controls to start data transmission if a second signal indicating that communication can be started or that channel use is available is received within the predetermined waiting time.[Item 9] The communication device according to any one of items 2 to 8, wherein the control unit performs the access control sequentially on the second access channel to the nth access channel after a predetermined waiting time has elapsed. [Item 10] The communication device according to item 1, wherein the control unit performs the access control sequentially on the second to nth access channels in an order determined by negotiation with the other communication device before performing the access control, until a usable channel is found. [Item 11] The communication device according to item 10, wherein the control unit performs the access control on the first access channel when it determines that the last channel determined by the negotiation among the second to nth access channels is unavailable. [Item 12] The communication device includes a control unit that controls a wireless communication unit that performs wireless communication with other communication devices on first to nth access channels (n is an integer of 2 or greater), wherein the control unit performs a standby operation on the first access channel set as a primary channel, and controls to perform a standby operation on a second access channel set as a channel other than the primary channel depending on a situation in which the other communication device determines that the primary channel is unavailable. [Item 13] The communication device according to item 12, wherein the control unit sequentially performs control to execute the standby operation on the second access channel through the nth access channel until a channel available for the other communication device is found. [Item 14] The communication device according to any one of items 12 to 13, wherein the control unit performs the standby operation on the first access channel depending on a situation in which it is determined that the nth access channel is unavailable for the other communication device. [Item 15] The communication device according to any one of items 12 to 14, wherein the control unit controls to execute the standby operation on the second access channel when a first signal indicating a request to start communication or use a channel is not received within a predetermined waiting time, addressed to the communication device itself. [Item 16] The communication device according to any one of items 12 to 15, wherein the control unit controls to transmit a second signal indicating that communication can be started or that channel use is available, based on reception of a first signal indicating a request to start communication or use a channel.[Item 17] The communication device according to any one of items 1 to 11, wherein the control unit controls transmission of Ch. Counts indicating the number of channels to be set as access channels to the other communication device. [Item 18] The communication device according to any one of items 1 to 11 and 17, wherein the control unit controls transmission of a Ch. List indicating a list of channels to be set as access channels, including a primary channel and at least one secondary channel, to the other communication device. [Item 19] The communication device according to any one of items 1 to 11 and 17 to 18, wherein the control unit controls transmission of a parameter corresponding to a first waiting time for the primary channel and a parameter corresponding to a second waiting time for at least one secondary channel to the other communication device. [Item 20] A communication control method comprising: performing wireless communication with another communication device over first to n-th access channels (n is an integer of 2 or greater); performing access control over a first access channel set as the primary channel; and performing the access control over a second access channel set other than the primary channel based on a situation in which it is determined that the first access channel is unavailable. [Item 21] The communication device of item 1, further comprising: a processor; an input device that accepts operations from a user; a display device; and a first antenna element, wherein the processor controls a display on the display device based on information received via the first to nth access channels and the operation. [Item 22] The communication device of item 21, further comprising: a speaker; an external connection interface for connecting to a memory card or a USB (Universal Serial Bus) device; a second antenna element that forms a MIMO antenna together with the first antenna element; and the power sharing unit that supplies power to the control unit, the processor, the input device, the display device, the second antenna element, and the external connection interface. [Item 23] The communication device of item 21, further comprising: a content player that plays content stored on an external storage medium connected via the external connection interface.[Item 24] The communication device according to Item 21, wherein the display device is an LED lamp that displays the operating status of the communication device. [Item 25] A vehicle, comprising: a control unit that controls a wireless communication unit that performs wireless communication with another communication device using first to nth access channels (n is an integer of 2 or greater), wherein the control unit: performs access control on a first access channel that is set as a primary channel, and performs the access control on a second access channel that is set other than the primary channel based on a situation in which it is determined that the first access channel is unavailable. [Item 26] A communication program that causes a computer to execute a communication method that performs wireless communication with another communication device using first to nth access channels (n is an integer of 2 or greater), performs access control on the first access channel that is set as the primary channel, and performs the access control on a second access channel that is set other than the primary channel based on a situation in which it is determined that the first access channel is unavailable. [Item 27] ​​A non-transitory medium having recorded thereon a communication program that causes a computer to execute a communication method comprising: performing wireless communication with another communication device over first to nth access channels (n is an integer equal to or greater than 2); performing access control over a first access channel that is set as a primary channel; and performing the access control over a second access channel that is set other than the primary channel based on a situation in which it is determined that the first access channel is unavailable. [Item 28] The communication device according to item 1, wherein the control unit initiates control to transition to the second access channel before a predetermined waiting time has elapsed. [Item 29] The communication device according to item 1, wherein the control unit completes control to transition to the second access channel before the start of the predetermined waiting time.

[0314] REFERENCE SIGNS LIST 1 Transmitting communication device 2 Receiving communication device 3 Transmitting OBSS 3' Transmitting OBSS 11 Internet connection unit 12 Information input unit 13 Control unit 14 Information output unit 15 Wireless communication unit 30 Channel allocation of transmitting communication device 31 Channel allocation of transmitting OBSS 32 Channel allocation of receiving OBSS 40 First access channel 41 Second access channel 42 Third access channel 43 Fourth access channel 44 Fifth access channel 110 Communication unit 111 Communication control unit 112 Communication storage unit 113 Common data processing unit 121 Individual data processing unit 122 Signal processing unit 123 Wireless interface unit 124 Amplification unit 140 Storage unit 150 Antenna 200 Wireless LAN system 301 Interface 302 Transmission buffer 303 Channel management unit 304 Frame construction unit 305 Available channel determination unit 306 Primary channel setting unit 307 Secondary channel setting unit 308 Transmission signal processing unit 309 Access control unit 311 Received signal detection unit 312 CCA determination unit 313 Frame analysis unit 314 NAV setting unit 315 Reception buffer 801 CPU 802 ROM 803 RAM 804 Bus 805 Input / output interface 806 Input unit 807 Output unit 808 Storage unit 809 Communication unit 810 Drive 811 Removable media 900 Smartphone 901 Processor 902 Memory 903 Storage 904 External connection interface 906 Camera 907 Sensor 908 Microphone 909 Input device 910 Display device 911 Speaker 913 Wireless communication interface 914 Antenna switch 915 Antenna 917 Bus 918 Battery 919 Auxiliary controller 920 In-vehicle device 921 Processor 922 Memory 924 GNSS module 925 Sensor 926 Data interface 927 Content player 928 Storage medium interface 929 Input device 930 Display device 931 Speaker 933 Wireless communication interface 934 Antenna switch 935 Antenna 938 Battery 940 In-vehicle system (or vehicle)941 In-vehicle network 942 Vehicle-side module 951 Controller 952 Memory 954 Input device 955 Display device 957 Network interface 958 Wired communication network 963 Wireless communication interface 964 Antenna switch 965 Antenna

Claims

1. A communication device comprising a control unit that controls a wireless communication unit that performs wireless communication with other communication devices using first to nth access channels (n is an integer of 2 or more), wherein the control unit executes access control on a first access channel set as a primary channel, and based on a determination that the first access channel is unavailable, executes the access control on a second access channel set on a channel other than the primary channel.

2. The communication device according to claim 1, wherein the control unit sequentially executes the access control on the second access channel to the nth access channel until an available channel is found.

3. The communication device according to claim 2, wherein when the control unit determines that the nth access channel is unavailable, the control unit executes the access control on the first access channel.

4. The communication device according to claim 1, wherein at least one channel among the channels from the second access channel to the nth access channel is selected from a frequency band set as a secondary channel.

5. The communication device according to claim 1, wherein at least one channel among the channels from the second access channel to the nth access channel is selected from outside a predetermined frequency band set as a primary channel and a secondary channel.

6. The communication device according to claim 1, wherein after a predetermined waiting time has elapsed, the control unit determines that the first access channel is unavailable and performs the access control on the second access channel.

7. The predetermined waiting time in the first access channel includes a random backoff time, and the control unit performs control to transmit a first signal indicating a communication start or a request for channel use after the random backoff time has elapsed. The communication device according to claim 6.

8. The communication device according to claim 7, wherein when the control unit receives a second signal indicating that communication start or channel use is possible within a predetermined waiting time, the control unit performs control to start data transmission.

9. The communication device according to claim 2, wherein the control unit sequentially performs the access control on the second access channel to the nth access channel after a predetermined waiting time has elapsed.

10. The control unit executes the access control for the second to nth access channels in the order determined by negotiation with the other communication device until an available channel is found, before executing the access control. The communication device according to claim 1.

11. If the control unit determines that the last channel determined by the negotiation among the second to nth access channels is unavailable, the control unit performs the access control on the first access channel. The communication device according to claim 10.

12. A communication device includes a control unit that controls a wireless communication unit that performs wireless communication with another communication device on first to nth access channels (n is an integer of 2 or more). The control unit executes a standby operation on the first access channel set as the primary channel, and based on a determination that the other communication device cannot use the primary channel, performs control to execute a standby operation on the second access channel set on a channel other than the primary channel.

13. The control unit performs control to sequentially execute the standby operation on the second access channel to the nth access channel until an available channel for the other communication device is found. The communication device according to claim 12.

14. The control unit performs the standby operation on the first access channel according to a situation where it is determined that the other communication device cannot use the nth access channel. The communication device according to claim 13.

15. If the control unit does not receive a first signal indicating a request for communication start or channel use addressed to the own device within a predetermined waiting time, the control unit performs control to execute a standby operation on the second access channel. The communication device according to claim 12.

16. The control unit performs control to transmit a second signal indicating that communication start or channel use is possible based on the reception of a first signal indicating a request for communication start or channel use. The communication device according to claim 12.

17. The control unit performs control to transmit Ch. Counts indicating the number of channels set as access channels to the other communication device. The communication device according to claim 1.

18. The communication device according to claim 1, wherein the control unit performs control to transmit a Ch.List indicating a list including a primary channel and at least one or more secondary channels and set as an access channel to the other communication device.

19. The communication device according to claim 1, wherein the control unit performs control to transmit a parameter corresponding to a first waiting time of the primary channel and a parameter corresponding to a second waiting time of at least one or more secondary channels to the other communication device.

20. A communication control method, comprising: performing wireless communication with another communication device using first to nth access channels (n is an integer of 2 or more); performing access control on a first access channel set as a primary channel; and performing the access control on a second access channel set other than the primary channel based on a situation where it is determined that the first access channel is unavailable.

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