Station, communication method, and integrated circuit

Abstract

To provide a communication device for enhanced direct link communication.SOLUTION: A communication apparatus is configured to communicate wirelessly with an access point (AP) on a first channel, the communication apparatus comprising: circuitry, which, in operation, generates a channel use permission request frame, the channel use permission request frame comprising information indicating the communication apparatus, another communication apparatus and a second channel that is different from the first channel; a transmitter, which, in operation, transmits the generated channel use permission request frame to the AP to seek permission from the AP to use the second channel for direct link communication with the another communication apparatus; and a receiver, which, in operation, receives a channel use permission response frame from the AP permitting use of the second channel, wherein the communication apparatus is further configured to communicate with the another communication apparatus on a direct link in the second channel after receiving the channel use permission response frame.SELECTED DRAWING: Figure 16

Description

Technical Field

[0001] The present disclosure relates to a communication device and a communication method for extended direct link communication, and more particularly, to a communication device and a communication method for extended direct link communication in a regulated band such as the 6 GHz band.

Background Art

[0002] In recent years, the FCC (Federal Communications Commission) has opened the 6 GHz band for unlicensed use. The 6 GHz band plays an important role in achieving throughput targets in future wireless standards such as IEEE 802.11ax (HE), IEEE 802.11be (EHT), and 3GPP's 5G standards.

[0003] To protect existing users, the FCC has proposed the following rules in the latest NPRM (Notice for Proposed Rulemaking). · The U-NII-5 and U-NII-7 subbands are widely used by point-to-point microwave links, including links that must maintain a high level of availability. Therefore, in these subbands, only "standard power access points (APs)" that use the power levels of the U-NII-1 and U-NII-3 bands can operate on the frequencies determined by the AFC (Automated Frequency Coordination) system. U-NII is an abbreviation for Unlicensed National Information Infrastructure. · The U-NII-6 and U-NII-8 subbands are used by mobile stations in locations where the position of existing receivers cannot be easily determined from existing databases and the use of AFC is difficult. Therefore, in these subbands, only indoor "low power access points" that use the lower power levels of the U-NII-2 band may be permitted. · The client device may be permitted to operate across the entire 6 GHz band under the control of either a standard power AP or a low power AP.

[0004] However, communication devices and communication methods for direct link communication in the 6 GHz band have not been discussed so far. In particular, in the U-NII-5 and U-NII-7 sub-bands, since the device may not be directly connected to the AFC system, it is unclear how devices involved in direct link communication may operate.

[0005] Therefore, there is a need for communication devices and methods that provide a feasible technical solution for extended direct link communication in the 6 GHz band. Further, other desirable features and characteristics will become apparent from the following detailed description and the appended claims, in conjunction with the accompanying drawings and the background of the present disclosure.

Summary of the Invention

[0006] Non-limiting embodiments of the present disclosure contribute to providing a communication device and a communication method for extended direct link communication.

[0007] According to a first embodiment of the present disclosure, a communication device configured to wirelessly communicate with an AP (access point) on a first channel, comprising: a circuit that generates a channel usage permission request frame including information indicating a second channel different from the communication device, the other communication device, and the first channel during operation; a transmitter that transmits the generated channel usage permission request frame to the AP to request permission from the AP to use the second channel for direct link communication with the other communication device during operation; and a receiver that receives a channel usage permission response frame that permits the use of the second channel from the AP during operation, and further configured to communicate with the other communication device via a direct link on the second channel after receiving the channel usage permission response frame.

[0008] According to a second embodiment of the present disclosure, there is provided a communication device configured to wirelessly communicate with an AP (access point), which includes, during operation, a circuit that generates a TDLS (Tunneled Direct Link Setup) RTS (Request To Send) frame including information indicating another communication device, a transmitter that transmits the generated TDLS RTS frame to the AP in order to request a TXOP (transmission opportunity) for TDLS transmission with the other communication device during operation, and a receiver that receives a TDLS CTS (Clear To Send) frame from the AP during operation, wherein the transmitter is further configured to transmit one or more data frames to the other communication device on a TDLS direct link within the requested TXOP after receiving the TDLS CTS frame.

[0009] According to a third embodiment of the present disclosure, there is provided an AP (access point) configured to wirelessly communicate with a communication device on a first channel, which includes, during operation, a receiver that receives a channel usage permission request frame from the communication device requesting use of a second channel different from the first channel for direct link communication with another communication device, a circuit configured to determine, after receiving the channel usage permission request frame, whether the second channel may be used by the communication device and the other communication device from a frequency adjustment database, and further generate a channel usage permission response frame including information indicating the determination, and a transmitter that transmits the channel usage permission response frame to the communication device configured to communicate with the other communication device based on the determination on a direct link on the second channel during operation.

[0010] According to a fourth embodiment of the present disclosure, there is provided an AP (Access Point) configured to wirelessly communicate with a communication device, which, during operation, includes information indicating another communication device and receives from the communication device a TDLS RTS (Request To Send) frame requesting a TXOP (Transmission Opportunity) for TDLS (Tunneled Direct Link Setup) transmission with the other communication device; a circuit that generates a TDLS CTS (Clear To Send) frame during operation; and a transmitter that transmits the TDLS CTS frame to the communication device during operation. After receiving the TDLS CTS frame, the communication device is configured to transmit one or more data frames to the other communication device on a TDLS direct link within the requested TXOP.

[0011] According to a fifth embodiment of the present disclosure, there is provided a communication method including generating a channel usage permission request frame including information indicating a communication device, another communication device, and a second channel different from a first channel, transmitting the generated channel usage permission request frame to an AP to request permission to use the second channel for direct link communication with the other communication device, receiving a channel usage permission response frame from the AP that permits use of the second channel, and communicating with the other communication device on the second channel via a direct link on the second channel after receiving the channel usage permission response frame.

[0012] Note that these general or specific aspects may be implemented in a system, method, integrated circuit, computer program, or recording medium, or may be implemented in any combination of a system, apparatus, method, integrated circuit, computer program, and recording medium.

[0013] Further advantages and effects in an embodiment of the present disclosure will be apparent from the specification and drawings. Such advantages and / or effects are provided respectively by several embodiments and the features described in the specification and drawings, but not all of them are necessarily provided to obtain one or more identical features.

Brief Description of Drawings

[0014] Embodiments of the present disclosure, in conjunction with the drawings, will be better understood and easily grasped by those skilled in the art from the following description for illustrative purposes only.

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[0015] Those skilled in the art can understand that the elements in the figures are shown simply and clearly, and are not necessarily drawn to a certain scale. For example, the dimensions of some elements in the figures, diagrams, or flowcharts may be exaggerated relative to other elements for the purpose of facilitating an accurate understanding of the present embodiment.

DETAILED DESCRIPTION OF THE INVENTION

[0016] Embodiments of the present disclosure are described with reference to the drawings for illustrative purposes only. Like reference numerals and letters in the drawings refer to like elements or equivalents.

[0017] In the following paragraphs, several exemplary embodiments will be described with reference to an access point (AP) and a terminal (STA) for extended direct link communication.

[0018] In IEEE 802.11 (Wi-Fi) technology, a terminal, also called a STA, is a communication device that supports the use of the 802.11 protocol. Based on the definition of IEEE 802.11-2016, a STA can be any device that includes a media access control (MAC) and a physical layer (PHY) interface compliant with IEEE 802.11 for a wireless medium (WM).

[0019] For example, a STA may be a notebook computer, a desktop personal computer (PC), a personal digital assistant (PDA), an access point in a wireless local area network (WLAN) environment, or a Wi-Fi telephone. A STA may be stationary or mobile. In a WLAN environment, the terms "STA", "wireless client", "user", "user device", "node" are often used interchangeably.

[0020] Similarly, in IEEE 802.11 (Wi-Fi) technology, an AP, also called a wireless access point (WAP), is a communication device that enables a STA in a WLAN to connect to a wired network. An AP typically connects to a router as a stand-alone device (via a wired network), but may be integrated with or incorporated into the router.

[0021] As described above, a STA in a WLAN can operate as an AP in some cases, and vice versa. This is because a communication device in IEEE 802.11 (Wi-Fi) technology may include both STA hardware components and AP hardware components. Thus, the communication device can switch between the STA mode and the AP mode based on actual WLAN conditions and / or requirements.

[0022] Direct link communication (also called peer-to-peer or device-to-device communication) has many advantages. In a conventional wireless network such as IEEE 802.11 WLAN, even if two devices involved in communication are included in the same wireless network (called BSS (Basic Service Set) in 802.11), all communication has to go through an access point (AP). To make such device-to-device communication more efficient, TDLS (Tunneled Direct Link Setup) was introduced in the IEEE 802.11z revision. TDLS is characterized by using setup frames encapsulated in data frames that can be transmitted transparently through the AP, so the term "tunneling" is used. For example, all management frames related to the setup of TDLS, such as TDLS setup request frames and TDLS setup response frames, are encapsulated within data frames, so the setup of TDLS is completely transparent to the AP. In fact, the AP may not even need to be TDLS-capable. The communication link between two devices using TDLS is known as a TDLS direct link, or simply a TDLS link. Packets between two devices are exchanged directly via the TDLS link without going through the AP, so TDLS can reduce packet transmission by half. Therefore, TDLS links can improve the efficiency of wireless networks, especially when two devices are relatively close to each other compared to the AP. In TDLS links, it is also possible to utilize a higher data rate due to the reduced distance between devices compared to the wireless link with the AP.

[0023] Figure 1A is a schematic diagram 100 for setting up direct peer-to-peer communication between two non-AP STAs. STA 104 can send a TDLS setup request frame to STA 106 via AP 102 (as shown in transmission paths 1a and 1b) to set up a direct link communication between STA 104 and STA 106. Then, in response to the reception of the TDLS request frame, STA 106 can send a TDLS setup response frame to STA 104 via AP 102 (as shown in transmission paths 2a and 2b). The TDLS setup request frame and the TDLS setup response frame are management frames for setting up TDLS and are directly transmitted between the data encapsulated and the AP, so the TDLS setup is transparent to AP 102. When TDLS is set up, the two STAs 104 and 106 can communicate directly with each other via a "direct link". The direct link may be switched to a channel different from the operating channel of the BSS (base channel), or may be on a different band, and such a direct link channel is called an "off-channel".

[0024] Currently, the AP does not control TDLS setup / usage. However, in the 6 GHz band, client devices are only permitted to operate in the 6 GHz band while under the control of the AP. When operating in the 5 GHz DFS (Dynamic Frequency Selection) band, the TDLS initiator STA operates as a DFS owner (DO), but in the 6 GHz band, there may be no such corresponding function for the TDLS STA.

[0025] Therefore, in the present invention, procedures for extended direct link communication in which the AP can control direct link communication more in a specific band / channel are described. Without such an extended function, a direct link such as TDLS may not be usable in the 6 GHz band.

[0026] When an AP operates in some sub-bands of the 6 GHz band (e.g., U-NII-5 and U-NII-7), it may be required to refer to an AFC database (Automatic Frequency control Database) to determine the allowed operating frequencies and transmission parameters. Such an AP may be called an ADD (AFC Database Dependent) enabled STA, and a non-AP STA associated with such an AP may be called an ADD dependent STA. A non-AP STA may be able to communicate on channels in these sub-bands only when it is "enabled" by an enabled STA, and such a non-AP STA may be considered to be "under the control of" the AP. The AP can notify its presence on channels that require enabling by periodically transmitting an enabling signal on the channel, for example, by including such an enabling signal in a beacon frame.

[0027] When two ADD dependent STAs negotiate a TDLS direct link on a base channel, they can use the same transmission parameters used for the AP link for transmission on the TDLS direct link.

[0028] Figure 1B is a schematic diagram 110 of TDLS direct link communication between two terminals (STAs) in a channel infrastructure network. Another advantage of TDLS is that since TDLS is transparent to the AP, when both devices support capabilities more advanced than the AP, the TDLS link can operate at higher capabilities that may not be supported by the AP. For example, AP 112 only supports 802.11ac, but two TDLS devices may both support the latest 802.11ax revision, in which case those devices can communicate over a direct link at the higher 802.11ax data rate. Further, even if two devices are multi-band devices and are connected to the AP in the 5 GHz band (base channel), if both devices support the 6 GHz band, the two devices may choose to switch the TDLS link to a wider channel in the 6 GHz band (off-channel TDLS link) even if the AP itself does not operate in the 6 GHz band.

[0029] As described above, AP 112 may refer to the AFC database 118 to determine the allowed operating frequencies and transmission parameters. And when the TDLS link between ADD-dependent STAs 114, 116 is in the BSS's operating channel, i.e., when the direct link is on the base channel, STAs 114, 116 may use the same transmission parameters used for the AP link for transmission over the TDLS link. In Figure 1B, a direct link is shown between the AP and the AFC database, but in reality, the AP may do so via the AFC system to check the channel availability in the AFC database. Alternatively, there may be no direct connection between the AP and the AFC database, and all decisions regarding the availability of channels (frequency usage) in a particular geolocation may be made by the AFC system.

[0030] However, when two non-AP STAs attempt to set or switch the TDLS direct link to a channel in the 6 GHz band rather than the base channel, the following rules shall apply. · The associated AP shall make the STA enabled for ADD. · The TDLS initiator STA shall request permission from the AP to use the channel for the direct link by transmitting a TDLS Channel Use Permission Request frame to the AP. · The AP shall respond by transmitting a TDLS Channel Use Permission Response frame. · The direct link may be set / switched to a channel in the 6 GHz band rather than the base channel only after receiving a TDLS Channel Use Permission Response frame containing the SUCCESS status from the AP.

[0031] Figure 1C is a schematic diagram 120 of direct link communication between two terminals (STAs) in a Wi-Fi Direct (peer-to-peer) network. The TDLS link can operate within a temporary wireless network such as a Wi-Fi Alliance Wi-Fi Direct network. A Wi-Fi Direct network is a device-to-device network where one device operates as a "group owner" (GO) and does not require a conventional AP. For example, in Figure 1C, the smartphone 122 operates as the GO, and the Wi-Fi-enabled printer 124 and the Wi-Fi-enabled digital camera 126 can participate in the Wi-Fi Direct network by forming a GO and Wi-Fi Direct connection. In this case, the GO operates as an AP, and a TDLS link may be established between the digital camera 126 and the printer 124 so that the digital camera 126 can directly send photos to the printer 124 for printing. Here too, if both the digital camera 126 and the printer 124 are multi-band devices and both support the 6 GHz band, the two devices may choose to switch the TDLS link to a wider channel in the 6 GHz band (off-channel TDLS link). In this example, the smartphone 122 can operate as an ADD-enabled STA as long as it can access the Internet and (via the AFC system) access the AFC database 128, and the two TDLS devices can give permission for transmission on the TDLS direct link in channels within the U-NII-5 and U-NII-7 sub-bands of the 6 GHz band.

[0032] Figure 2 is a message flow showing TDLS setup in the 6 GHz off-channel according to the first embodiment. AP202 may be an ADD-enabled STA. Non-AP STAs 204 and 206 are associated with AP202 in a 6 GHz band channel. For various reasons, non-AP STAs 204 and 206 can choose to communicate through a direct link on a channel different from the operating channel of the BSS. Due to regulatory requirements in the 6 GHz band, it may be required to confirm the channel availability from the AFC system before any transmission on the channel. Non-AP STA 204, which is the TDLS initiator STA, can request permission from AP202 to use a different channel in the 6 GHz band for direct link communication with non-AP STA 206 by transmitting a TDLS Channel Use Permission Request frame 208 to AP202. The channel may be, for example, a channel in the 6 GHz band U-NII-5 or U-NII-7 subband different from the 6 GHz band base channel used for communication between AP202 and STAs 204 and 206.

[0033] After receiving a TDLS Channel Use Permission Request frame 208 from STA204, AP202 checks the AFC database (e.g., via the AFC system) regarding the availability of the requested channel. If successful, AP202 may send a TDLS Channel Use Permission Response frame 210 containing a SUCCESS status to STA204 to indicate that the requested channel is available for direct link communication. Then, STA204 can initiate the setup of a direct link with STA206 on the requested channel by sending a TDLS Setup Request frame 212 to STA206 via AP202. STA206 may respond by sending a TDLS Setup Response frame 214 to STA204 via AP202. Thereafter, STA204 sends a TDLS Setup Confirm frame 216 to STA206 via AP202, and a TDLS direct link is set up on the requested channel in the 6 GHz band. If the check of the AFC database fails and the requested channel is unavailable, AP202 may send a TDLS Channel Use Permission Response frame 210 containing a failure status (e.g., TDLS_CHANNEL_USE_DENIED) to STA204 to indicate that the use of the requested channel for direct link communication has been rejected.

[0034] FIG. 3 is a message flow showing TDLS direct link channel switching to an off-channel in the 6 GHz band according to the first embodiment. In this example, non-AP STAs 304 and 306 are associated with AP 302 on a channel in the 5 GHz band, and a TDLS direct link is already set up on the base channel. However, STA 304 attempts to switch the direct link to an off-channel in the 6 GHz band. Therefore, STA 304, which is the TDLS initiator STA, can request permission from AP 302 to use another channel in the 6 GHz band for direct link communication with STA 306 by transmitting a TDLS Channel Use Permission Request frame 308 to AP 302. The channel may be, for example, a channel in the 6 GHz band different from the 5 GHz band base channel used for communication between AP 302 and STAs 304 and 306.

[0035] After receiving a TDLS Channel Use Permission Request frame 308 from STA304, AP302 checks the AFC database regarding the availability of the requested channel. If successful, AP302 may send a TDLS Channel Use Permission Response frame 310 containing a SUCCESS status to STA304 to indicate that the requested channel is available for direct link communication. Then, STA304 can initiate a switch of the direct link with STA306 to the requested channel in the 6 GHz band by sending a TDLS Channel Switch Request frame 312 to STA306. STA306 responds by sending a TDLS Channel Switch Response frame to STA304 with a SUCCESS status, and the TDLS direct link is switched to the requested channel in the 6 GHz band. If the check of the AFC database fails and the requested channel is unavailable, AP302 may send a TDLS Channel Use Permission Response frame 310 containing a FAILURE status to AP304 to indicate that the switch of the direct link to the requested channel has been rejected.

[0036] It will be understood that if STA204, 304 (TDLS initiator STA) has the ability to directly check the AFC database regarding off-channel use in the 6 GHz band for a direct link (e.g., via a cellular internet link), there is no need to request permission from AP202, 302, and the direct link to the off-channel can be directly set / switched.

[0037] FIG. 4A is a diagram showing the format of a TDLS Setup Request frame 400 used to request TDLS direct link setup according to various embodiments. The TDLS Setup Request frame 400 may be used in the form of a TDLS Setup Request frame 212 transmitted by the STA 204 via the AP 202 to the STA 206 as shown in FIG. 2. The TDLS Setup Request frame 400 may include (or be composed of) a Frame Control field, a Duration field, one or more Address fields, a Sequence Control field, an HT Control field, a Category field, a TDLS Action field, a Dialog Token field, an optional Target Channel field, an optional Wide Bandwidth Channel Switch element field, and an FCS (frame check sequence) field. The Target Channel field may include (or be composed of) an Operating Class field and a Channel Number field. The Channel Number field may indicate the channel used for the requested direct link communication. The Target Channel field and the Wide Bandwidth Channel Switch element field may be present in the TDLS Setup Request frame 400 to request TDLS setup on a channel different from the base channel.Also, a Wide Bandwidth Channel Switch element field may exist when the TDLS Setup Request frame 400 is used to request a channel wider than 20 MHz. Although not shown, when a TDLS link is set in a different frequency band and the MAC address of the STA on that frequency band is different from the band where the base channel exists, the MAC address on the other band may also be included in the TDLS Setup Request frame. When the peer STA accepts the TDLS setup request, it may include its own MAC address on the other band in the TDLS Setup Request Response frame. If necessary, setting the TDLS link on a different channel may also trigger the setting of the TPK (TDLS PeerKey) security association on other channels.

[0038] Figure 4B is a diagram showing the format of a TDLS Channel Use Permission Request frame 410 used to request channel use permission for direct link communication according to the first embodiment. The TDLS Channel Use Permission Request frame 410 may be used in the form of TDLS Channel Use Permission Request frames 208 and 308 transmitted by STAs 204 and 304 to APs 202 and 302, as shown in FIGS. 2 and 3. The TDLS Channel Use Permission Request frame 410 may include (or be composed of) a Frame Control field, a Duration field, one or more Address fields, a Sequence Control field, an HT Control field, a Category field, a TDLS Action field, a Dialog Token field, a Link Identifier element field, optionally a Device Information field, a Target Channel field, optionally a Wide Bandwidth Channel Switch element field, and an FCS field. The Device Information field may include (or be composed of) a First Device ID field, a First Device Location field, a Second Device ID field, and a Second Device Location field.The device ID may be, for example, the FCC ID of the device and may be used by the AFC system to verify whether the device may be used on that channel. Similarly, the Device Location field may provide information on the geographical location of the device, such as latitude, longitude, and optionally the height of the antenna. The Target Channel field may include (or be composed of) an Operating Class field and a Channel Number field (not shown) that identifies the channel required for the direct link communication. Also, a Wide Bandwidth Channel Switch element field may be present when a channel wider than 20 MHz is required. The device location information may be used by the AFC system to calculate whether transmissions from any TDLS device on the required channel can interfere with license users operating in the vicinity. Such a determination by the AFC system may take into account many factors, including information on the receiving antennas of license users and the terrain (rural, urban, semi-urban), etc. If the AFC system determines that the direct link transmission on the required channel does not cause any interference to the surrounding license users, the use of the channel required for the direct link communication may be permitted. Alternatively, the AFC system can simplify the interference calculation by using information about the AP (location, antenna height, etc.) to perform the interference calculation under the assumption that the transmission by the AP on the required channel does not interfere with the license user, and it can be assumed that transmissions by any client device (i.e., TDLS STA) do not interfere with the license user.

[0039] FIG. 4C is a diagram showing the format of a TDLS Channel Use Permission Response frame 420 used to respond to a TDLS Channel Use Permission Request frame 410 according to the first embodiment. The TDLS Channel Use Permission Response frame 420 may be used in the form of TDLS Channel Use Permission Response frames 210, 310 transmitted by the APs 202, 302 to the STAs 204, 304 as shown in FIGS. 2 and 3. The TDLS Channel Use Permission Response frame 420 may include (or be composed of) a Frame Control field, a Duration field, one or more Address fields, a Sequence Control field, an HT Control field, a Category field, a TDLS Action field, a Dialog Token field, a Status field, a Maximum Power Level field, a Validity Period field, an optional Alternate Channel field, an optional Wide Bandwidth Channel Switch element field, and an FCS field.

[0040] The Status field indicates "SUCCESS" if the channel requested in the TDLS Channel Use Permission Request frame is available for direct link communication, and may indicate "TDLS_CHANNEL_USE_DENIED" if the channel requested in the TDLS Channel Use Permission Request frame (e.g., the channel indicated by the Channel Number field of the TDLS Channel Use Permission Request frame) is not available for direct link communication. If the status is not SUCCESS, the AP may include an Alternate Channel field and a Wide Bandwidth Channel Switch element in the TDLS Channel Use Permission Response frame to recommend another channel for direct link communication. Also, the TDLS Channel Use Permission Response frame 420 may include applicable transmission parameters (e.g., Maximum Transmit Power level), and the expiration period for the use of the channel, etc.

[0041] The Maximum Power Level field may indicate, in units of 0.5 dBm, the maximum power permitted to be transmitted on the channel indicated by the Channel Number field. The Validity Period field may indicate the period during which the Channel Use Permission is valid. The STA is required to request permission again from the associated AP, for example, by transmitting another TDLS Channel Use Permission Request frame to the associated AP, when the validity period expires. The TDLS Channel Use Permission Request / Response frame may be understood to be transmitted directly between the STA and the AP without data encapsulation.

[0042] Furthermore, a non-AP STA may be required to set up a traffic stream (TS) for a TDLS direct link in the 6 GHz band before transmitting a data frame over the TDLS direct link. FIG. 5 is a message flow showing the setup of a TS for a TDLS direct link in a 6 GHz band channel according to the first embodiment. STA504 can transmit an Add Traffic Stream Request frame 508 to AP502. The Add Traffic Stream Request frame 508 may include information identifying the TDLS direct link. For example, STA504 may include a Link Identifier element in the Add Traffic Stream Request frame 508 for notification of the TS for TDLS and identification of the addresses of the initiator STA (e.g., STA504) and the receiving STA (e.g., STA506). If AP502 permits the TS, AP502 creates a TS for the TDLS direct link. By having information about both STAs involved in the TDLS link, the AP can make a more appropriate decision. For example, if the AP knows that two STAs are physically close to each other, it can provide more transmission opportunities for the direct link, or it can reject traffic setup requests between STAs that are far apart from each other to prevent interference with other STAs.

[0043] In addition, AP502 may send an ADDTS response frame 510 to STA504 and include a Link Identifier element indicating the TDLS link within the ADDTS response frame 510. When the TS is bidirectional, STA504 may send a TDLS Setup Confirm frame 512 to STA506 to notify STA506 that the TS setup has been successful. The TDLS Setup Confirm frame 512 may notify the TSPEC (Traffic Specification) and TID (Traffic ID) of the TS. Alternatively, STA506 may repeat the TS setup in the reverse direction. In this example, it is assumed that a TDLS direct link has already been set up between STA504 and STA506. Otherwise, the two STAs 504 and 506 can perform the TDLS setup immediately after the setup of the traffic stream for the TDLS link has been successful. After the setup of the TS has been successful, one or more data frames 514 belonging to the TID may be sent over the TDLS direct link. If a TS is required for the TDLS direct link, data frame transmission over the TDLS direct link is not permitted if the TDLS TS setup fails. By setting the TS by AP502, AP502 can establish control over the communication traffic between non-AP STAs 504 and 506, which is advantageous.

[0044] The operating channel of the BSS is in the 5 GHz or 2.4 GHz band. When the TDLS direct link is switched to a channel in the 6 GHz band (off-channel case), the TS of TDLS may be set to the 6 GHz band, but the actual TDLS TS setting is performed on the operating channel of the BSS. FIG. 6 is a message flow showing the setting of a traffic stream for a TDLS direct link in the 6 GHz band off-channel according to the first embodiment. STA604 can send an ADDTS Request frame 608 to AP602 on the BSS operating channel. The ADDTS Request frame 608 may include information for identifying the TDLS direct link. For example, STA604 may include a Link Identifier element in the ADDTS Request frame 608 for the notification of the TS for TDLS and the identification of the addresses of the initiator STA (e.g., STA604) and the receiving STA (e.g., STA606). Also, the ADDTS Request frame 608 may include a multi-band element indicating the 6 GHz band and the channels that can be switched in the 6 GHz band. When AP602 permits the TS, AP602 creates a TS for the TDLS direct link in the 6 GHz band.

[0045] Also, AP602 may send an ADDTS response frame 610 to STA604 on the BSS operating channel, and the ADDTS response frame 610 may include a Link Identifier element indicating the TDLS link. Further, the ADDTS response frame 610 may include a multi-band element indicating the channel switched in the 6 GHz band. Then, STA604 can send a TDLS Setup Confirm frame 612 to STA606 via AP602 (i.e., encapsulated in a data frame) to notify STA606 that the TS setting has been successful. The TDLS Setup Confirm frame 612 may notify the TSPEC (Traffic Specification) and TID (Traffic ID) of the TS. In this example, it is assumed that a TDLS direct link has already been set up between STA504 and STA506 on the 6 GHz channel. After the TS setting is successful, one or more data frames 614 belonging to the TID may be sent on the TDLS direct link, and at this time, STA604 and STA606 may be in the PS (Power Save) mode with respect to AP602. By setting the TS by AP602, AP602 can establish control over the communication traffic between non-AP STAs 604 and 606, which is advantageous.

[0046] The AP can notify that TDLS TS setting is required for the AC in the 6 GHz band by setting the "TDLS ACM" bit in the parameter record field of the AC (Access Category) within the Enhanced Distributed Channel Access Parameter Set element transmitted in the 6 GHz band Beacon / Probe Response frame. FIG. 7 is a diagram showing the format of the EDCA Parameter Set element 700 according to the first embodiment. The EDCA Parameter Set element 700 may include (or be composed of) an Element ID field, a Length field, a QoS Info field, an Update EDCA Info field, an AC_BE Parameter Record field, an AC_BK Parameter Record field, an AC_VI Parameter Record field, and an AC_VO Parameter Record field. The AC_BK Parameter Record field may include (or be composed of) an ACI / AIFSN field, an ECWmin / ECWmax field, and a TXOP Limit field. The ACI / AIFSN field may include (or be composed of) an AIFSN subfield, an ACM subfield, an ACI subfield, and a TDLS ACM subfield. When the TDLS ACM subfield bit is set, data transmission on the TDLS direct link in the 6 GHz band is permitted only after the STA sets the TDLS TS for that AC with the AP (regardless of the setting of the ACM bit for that AC).On the one hand, when the TDLS ACM subfield bit is not set, data transmission on the 6 GHz band TDLS direct link is permitted for that AC without requiring a TS setting. The TDLS ACM subfield allows the AP to have more control over direct link communication in non-AP STAs, which is advantageous.

[0047] FIG. 8 is a diagram showing the formats of an ADDTS Request frame 800 and an ADDTS Response frame 802 according to the first embodiment. The ADDTS Request frame 800 may be used in the form of ADDTS Request frames 508 and 608 transmitted by STAs 504 and 604 to APs 502 and 602 as shown in FIGS. 5 and 6. The ADDTS Request frame 800 may include (or be composed of) a Frame Control field, a Duration field, an Address 1 (RA) field, an Address 2 (TA) field, an Address 3 (BSSID) field, a Sequence Control field, an HT Control field, a Category field, a QoS Action field, a Dialog Token field, a TSPEC element field, a Link Identifier element field, and an FCS field. As shown in the examples of FIGS. 5 and 6, the ADDTS Request frame is transmitted by the initiator STA to the AP to request that the AP set a TS for the direct link.

[0048] The ADDTS Response frame 802 may be used in the form of ADDTS Response frames 510, 610 transmitted by the APs 502, 602 to the STAs 504, 604 as shown in FIGS. 5 and 6. The ADDTS Response frame 802 may include (or be composed of) a Frame Control field, a Duration field, an Address 1 (RA) field, an Address 2 (TA) field, an Address 3 (BSSID) field, a Sequence Control field, an HT Control field, a Category field, a QoS Action field, a Dialog Token field, a Status Code field, a TS Delay field, a TSPEC Element field, a Link Identifier Element field, and an FCS field. As shown in the examples of FIGS. 5 and 6, the ADDTS Response frame is transmitted by the AP to the initiator STA to confirm that the TS has been set. The TDLS direct link may be identified by a Link Identifier Element field that may include (or be composed of) an Element ID field, a Length field, a BSSID field, a TDLS Initiator STA Address field, and a TDLS Responder STA Address field within the ADDTS Request / Response frame.

[0049] The AP may instruct an associated non-AP STA to cease operation on a 6 GHz band TDLS direct link by including a Cease Operation element within a broadcast / unicast frame addressed to the STA. For example, such a cease operation instruction may be sent by the AP when a primary user of the spectrum is detected (e.g., due to a change in the AFC database), when there is an instruction from the AFC system, or in other similar situations. Such requirements for ceasing operation may include immediately ceasing all ongoing transmissions and may be mandated by a regulatory agency to protect licensed users of the spectrum from harmful interference. FIG. 9 is a diagram showing the format of a Cease Operation element 900 used for a cease operation instruction according to the first embodiment. The Cease Operation element 900 may include (or be composed of) an Element ID field, a Length field, an Extended Element ID field, a BSSID field, a Band ID field, an Operating Class field, an Operating Channel field, and a Reason Code field. The Band ID field (if present), the Operating Class field, and the Operating Channel field together identify the frequency band and channel to which the cease operation applies. The Reason Code field may indicate the reason why the STA is required to cease operation on the direct link. For example, a value of "0" indicates that a primary or licensed use has been detected, a value of "1" indicates that the use of the channel has not been permitted in the AFC database by the AFC system, and other values from 2 to 255 may be reserved for other reasons. For example, other reasons may include that a licensed user of the channel has reported interference to the AFC system.

[0050] When the STA receives a stop operation instruction from the AP together with the Cease Operation element 900, it stops all operations on the TDLS direct link on the indicated channel. This may include, for example, stopping transmissions on the direct link, disconnecting the direct link, or deleting the TDLS TS associated with the direct link. By using the stop operation instruction, the AP can advantageously control the TDLS direct link setup / transmission in the 6 GHz band.

[0051] In the second embodiment, the AP may permit only scheduled transmission of data frames even for a TDLS direct link, and thus, TDLS data frame transmission may require reception of a TDLS Trigger frame from the AP. By requesting TS settings for the TDLS link from the TDLS STA, the AP can somewhat control transmission on the TDLS link, but in some regulatory regions, the AP may need to control much more strictly which STA can transmit on the wireless medium and when. In such a scenario, the AP may disable all contention-based transmissions (e.g., EDCA) and permit only transmissions scheduled by the AP. When the TDLS initiator STA receives a TDLS Trigger frame, it can transmit one or more data frames to the TDLS receiving STA on the TDLS direct link within the TXOP period. FIG. 10 is a message flow showing direct link communication between two STAs in a TXOP according to the second embodiment. The AP 1002 can generate and transmit a TDLS Trigger frame 1008 to the STA 1004. The STA 1004 receives the TDLS Trigger frame 1008 and, after a SIFS (Short Interframe Spacing) 1010, transmits one or more TDLS Data frames 1012 to the STA 1006 within the TXOP 1016. The STA 1006 can acknowledge each TDLS data frame 1012 received from the AP 1004 by transmitting an acknowledgment response frame 1014 (ACK frame or BlockAck frame) to the STA 1004.In various embodiments, the TDLS Trigger frame 1008 may include information indicating the MAC address of the STA 1004, the permitted access category (AC), and the maximum transmit power level, and one or more data frames are transmitted to the MAC address and based on the TID specified by the permitted AC or a higher AC, and one or more data frames are transmitted at a transmit power less than the maximum transmit power level.

[0052] EDCA-based transmission of data frames is not permitted over TDLS direct links. Also, such triggered transmission according to the second embodiment is possible only when the TDLS direct link is within the base channel. Therefore, TDLS channel switching to an off-channel in the 6 GHz band may not be permitted. The AP 1002 may use the TDLS TS parameters as well as the TDLS Buffer Status Report to schedule the transmission of the TDLS Trigger frame 1008.

[0053] FIG. 11A is a diagram showing the format of a TDLS Trigger frame 1100 used to initiate a direct link communication according to the second embodiment. As shown in FIG. 10, the TDLS Trigger frame 1100 can be utilized in the form of the TDLS Trigger frame 1008. The TDLS Trigger frame 1100 may include (or be composed of) a Frame Control field, a Duration field, an RA field, a TA field, a Common Info field, a User Info field, a Padding field, and an FCS field. The RA field may be set, for example, to the MAC address of the TDLS initiator STA. In the example shown in FIG. 10, this is the MAC address of the STA 1004 that transmits the data frame 1012. The Common Info field may include a Trigger Type field, and the Trigger Type field may include a value "8" indicating that the frame is a TDLS Trigger frame. Other fields in the Common Info field, except for the Trigger Type field and the CS Required field, may all be reserved. There is no Trigger Dependent Common Info field. The User Info field may include an AID12 field and a Trigger Dependent User Info field. There may be only one User Info field. The AID12 field may be set to the AID of the TDLS initiator STA. In the example shown in FIG. 10, this is the AID of the STA 1004.The Trigger Dependent User Info field may further include (or be composed of) a Destination MAC address field, an Allowed AC field, and a Maximum Power Level field. The Destination MAC address field may indicate, for example, the MAC address of the TDLS receiving STA. In the example shown in FIG. 10, this is the MAC address of STA1006 which is the target for receiving data frame 1012. All other fields of the Trigger Dependent User Info field may be reserved. The TDLS initiator STA that receives the TDLS Trigger frame 1100 may be permitted to transmit a data frame destined for the TDLS receiving STA from either the AC indicated in the Allowed AC field or from another TID from a higher priority AC.

[0054] FIG. 11B is a diagram showing an alternative format of a TDLS Trigger frame used to initiate direct link communication according to the second embodiment. The format of the TDLS Trigger frame can be simplified, as an alternative, to a form as shown in TDLS Trigger frame 1102. TDLS Trigger frame 1102 may include (or be composed of) a Frame Control field, a Duration field, an RA field, a TA field, a Trigger Type field, a CS Required field, an Allowed AC field, a Maximum Power Level field, a Destination MAC address field, and an FCS field. Therefore, TDLS Trigger frame 1008 in FIG. 10 may be in the form of the simplified TDLS trigger frame 1102.

[0055] Also, a new TDLS Action frame (TDLS Buffer Status Report) may be defined for the STA to report its TDLS buffer status to the AP. FIG. 12 is a diagram showing the format of a TDLS Action frame 1200 used to report the TDLS buffer status according to the second embodiment. The TDLS Buffer Status Report frame 1200 may include (or be composed of) a Frame Control field, a Duration field, an Address 1 field, an Address 2 field, an Address 3 field, a Sequence Control field, an HT Control field, a Category field, a TDLS Action field, a Link Identifier element field, one or more TDLS Buffer Status fields, and an FCS field. Each TDLS Buffer Status field may include (or be composed of) a TID field and a Queue Size field. The TDLS Action field may have a value of, for example, "11" to indicate that the action frame is a TDLS Buffer Status Report frame. The Link Identifier element field may include information for identifying the TDLS link. The TID may indicate the TID corresponding to the TDLS data frame. The Queue Size field may indicate the queue size of the TID corresponding to the data frame destined for the TDLS peer STA, and the same encoding as the Queue Size subfield of the QoS Control field may be used.When a TS is set for a TDLS direct link, the TID field may correspond to the TSID.

[0056] The TDLS Buffer Status Report frame 1200 may be transmitted directly between the AP without data encapsulation. The AP can advantageously use the information provided in the TDLS Buffer Status Report frame 1200 to dynamically schedule the TDLS Trigger frames 1100, 1102 to initiate TDLS transmission in the 6 GHz band.

[0057] The AP can notify, for example, in the Extended Capabilities field of the Beacon / Probe Response frame, whether a TS setting is required for a 6 GHz TDLS direct link (bit #83), and / or whether a Trigger frame is required for data frame transmission in a 6 GHz TDLS direct link (bit #84). Table 1 below shows the values of the bits that can be used by the AP in the Extended Capabilities field of the Beacon / Probe Response frame to notify the above requirements. The AP can more effectively control the requirements for enabling TDLS direct link transmission in the 6 GHz band, which is advantageous.

[0058] [Table 1]

[0059] According to the third embodiment, new RTS (Request to Send) and CTS (Clear to Send) frames can be defined for the request and approval of TDLS transmission. FIG. 13 is a diagram showing the formats of a TDLS RTS frame 1300 and a TDLS CTS frame 1302 according to the third embodiment. The TDLS RTS frame 1300 may be transmitted from a TDLS initiator STA to an associated AP to request a TXOP for TDLS transmission with another STA (for example, a TDLS receiving STA). The TDLS RTS frame 1300 may include (or be composed of) a Frame Control field, a Duration field, an RA field, a TA field, a Destination MAC address field, and an FCS field. The RA field may be set to, for example, the MAC address of the TDLS initiator STA, and the Destination MAC address field may be set to the MAC address of the TDLS receiving STA. The TDLS RTS frame is different from a normal RTS frame in that it includes a Destination MAC address field.

[0060] If the AP permits TDLS transmission, the TDLS CTS frame 1302 may be sent by the AP to the TDLS initiator STA. The TDLS CTS frame 1302 may include (or be composed of) a Frame Control field, a Duration field, an RA field, a Destination MAC address field, and an FCS field. Similar to the Destination MAC address field of the TDLS RTS frame 1300, the Destination MAC address field of the TDLS CTS frame 1302 may be set to the MAC address of the TDLS receiving STA. The TDLS CTS frame is different from a normal CTS frame in that it includes a Destination MAC address field.

[0061] According to the third embodiment, the transmission of data frames over the TDLS direct link can be permitted only after an RTS / CTS exchange with the AP. Also, since transmission is possible only when the TDLS direct link is in the base channel, switching of the TDLS channel to an off-channel in the 6 GHz band is not permitted. The RTS / CTS exchange enables the AP to dynamically permit / deny TDLS transmission in the 6 GHz band, which is advantageous. One advantage of using this RTS and CTS procedure to initiate communication over the TDLS link is that the scheduling load on the AP regarding the TDLS link is eliminated, and while the TDLS initiator STA (STA1 1404 in this example) initiates the TDLS TXOP, the AP can still strictly control whether transmission over the TDLS direct link is permitted.

[0062] Figure 14 is a message flow showing direct link communication between two STAs in a TXOP according to the third embodiment. STA 1404 can generate and send a TDLS RTS frame 1408 to AP 1402 to request a TXOP 1416 for TDLS transmission with STA 1406. The TDLS RTS frame 1408 can take the form of the TDLS RTS frame 1300 shown in FIG. 13 and may include information indicating STA 1406, such as the MAC address of STA 1406. Then, upon receiving the TDLS RTS frame 1408, AP 1402 can generate and send a TDLS CTS frame 1410 to STA 1402 to permit transmission. The TDLS CTS frame 1410 can take the form of the TDLS CTS frame 1302 shown in FIG. 13 and may include information indicating STA 1406, such as the MAC address of STA 1406. Then, after receiving the TDLS CTS frame 1410, STA 1404 can send one or more data frames 1412 to STA 1406 within the requested TXOP 1416. STA 1406 can send an acknowledgment frame 1414 to STA 1404 to acknowledge each data frame. In this example, it is assumed that both STA 1404 and STA 1406 are operating in the active mode (i.e., not in the power save mode).

[0063] FIG. 15 is a partially sectional schematic view of a communication device 1500 according to various embodiments. The communication device 1500 can be implemented as an AP or a STA according to various embodiments.

[0064] As shown in FIG. 15, the communication device 1500 may include a circuit 1514, at least one wireless transmitter 1502, at least one wireless receiver 1504, and at least one antenna 1512 (for simplicity, only one antenna is depicted in FIG. 15 for illustrative purposes). The circuit 1514 may include at least one control unit 1506, and the at least one control unit 1506 is used when executing tasks (including control of communication with one or more other communication devices in a wireless network) designed to be executed with the assistance of software and hardware. The circuit 1514 may further include at least one transmission signal generation unit 1508 and at least one reception signal processing unit 1510. The at least one control unit 1506 is responsible for frames transmitted to one or more other communication devices via the at least one wireless transmitter 1502 (for example, when the communication device 1500 is a STA, TDLS Setup Request frame, TDLS Setup Response frame, TDLS Channel Use Permission Request frame, ADDTS request frame, and TDLS RTS frame; and for example, when the communication device 1500 is an AP, TDLS Channel Use Permission Response frame, ADDTS response frame, EDCA Parameter Set element frame, cease operation instruction frame, TDLS Trigger frame, TDLS Buffer Status Report frame, and TDLSTo generate a CTS frame), at least one transmission signal generation unit 1508 may be controlled, and also, frames received from one or more other communication devices via at least one wireless receiver 1504 under the control of at least one control unit 1506 (for example, when the communication device 1500 is a STA, a TDLS Channel Use Permission Response frame, an ADDTS response frame, an EDCA Parameter Set element frame, a cease operation instruction frame, a TDLS Trigger frame, a TDLS Buffer Status Report frame, and a TDLS CTS frame, and also for example, when the communication device 1500 is an AP, a TDLS Setup Request frame, a TDLS Setup Response frame, a TDLS Channel Use Permission Request frame, an ADDTS request frame, and TDLSTo process the RTS frame, at least one receiving signal processing unit 1510 may be controlled. At least one transmitting signal generating unit 1508 and at least one receiving signal processing unit 1510 may be stand-alone modules of the communication device 1500 that communicate with at least one control unit 1506 for the above-described functions, as shown in FIG. 15. Alternatively, at least one transmitting signal generating unit 1508 and at least one receiving signal processing unit 1510 may be included in at least one control unit 1506. It should be understood by those skilled in the art that the arrangement of these functional modules is flexible and can be changed according to actual needs and / or requirements. Data processing, storage, and other related control devices can be provided on appropriate circuit boards and / or chip sets. In various embodiments, during operation, at least one wireless transmitter 1502, at least one wireless receiver 1504, and at least one antenna 1512 may be controlled by at least one control unit 1506.

[0065] The communication device 1500 provides functions necessary for extended direct link communication during operation. For example, the communication device 1500 may be a STA configured to wirelessly communicate with an AP on a first channel, and a circuit 1514 (for example, at least one transmitting signal generating unit 1508 of the circuit 1514) may generate a channel usage permission request frame including information indicating a second channel different from the first channel between the communication device 1500, another communication device, and the first channel during operation. The wireless transmitter 1502 may transmit the generated channel usage permission request frame to the AP to request permission from the AP to use the second channel for direct link communication with the other communication device during operation. The wireless receiver 1504 may receive a channel usage permission response frame permitting the use of the second channel from the AP during operation, and the communication device 1500 is further configured to communicate with the other communication device via a direct link on the second channel after receiving the channel usage permission response frame.

[0066] The direct link may be a TDLS direct link. The channel usage permission response frame may include information indicating a maximum transmission power level and a validity period for using the second channel, and the communication between the communication device and the other communication device on the direct link is stopped when the validity period expires.

[0067] Further, the wireless receiver 1504 may be further configured to receive a stop operation instruction from the AP, and the communication device 1500 is further configured to stop the communication on the direct link after receiving the stop operation instruction.

[0068] Furthermore, the circuit 1514 (for example, at least one transmission signal generation unit 1508 of the circuit 1514) may be further configured to generate an ADDTS request frame including information for identifying the direct link, and the wireless transmitter 1502 may be further configured to transmit the generated ADDTS request frame to the AP to request the AP to set up a traffic stream for the direct link. The wireless receiver 1504 may be further configured to receive an ADDTS response frame from the AP verifying that the traffic stream has been set up, and the wireless transmitter 1502 may be further configured to transmit a data frame belonging to the traffic stream to the other communication device.

[0069] For example, the communication device 1500 may be a STA, the wireless receiver 1504 may receive a trigger frame from an AP during operation, and the wireless transmitter 1502 may, during operation, after receiving the trigger frame, transmit one or more data frames to another communication device on a direct link. The trigger frame may be, for example, a TDLS Trigger frame. The trigger frame may include information indicating the MAC address of the other communication device, a permitted AC (access category), and a maximum transmission power level. The one or more data frames are transmitted to the MAC address and are transmitted at a transmission power smaller than the maximum transmission power level based on a TID (traffic identifier) specified by the permitted AC or a higher AC. Further, the wireless transmitter 1502 may be further configured to periodically transmit a buffer status report frame to the AP, which further includes information indicating the direct link, for reporting the size of buffer data corresponding to the TID and addressed to the other communication device.

[0070] For example, the communication device 1500 may be a STA configured to wirelessly communicate with an AP, and the circuit 1514 (for example, at least one transmission signal generation unit 1508 of the circuit 1514) may generate a TDLS RTS frame including information indicating another communication device during operation. The wireless transmitter 1502 may transmit the generated TDLS RTS frame to the AP during operation to request a TXOP (transmission opportunity) for TDLS transmission with the other communication device. The wireless receiver 1504 may receive a TDLS CTS frame from the AP during operation, and the wireless transmitter 1502 is further configured to transmit one or more data frames to the other communication device on a TDLS direct link within the requested TXOP after receiving the TDLS CTS frame.

[0071] For example, the communication device 1500 may be an AP configured to wirelessly communicate with a communication device on a first channel. The wireless receiver 1504 may receive, during operation, a channel usage permission request frame from the communication device, which requests the use of a second channel different from the first channel for direct link communication with another communication device. The circuit 1514 may, during operation, after receiving the channel usage permission request frame, determine from the frequency adjustment database whether the second channel may be used by the communication device and the other communication device. The circuit 1514 (for example, at least one transmission signal generation unit 1508 of the circuit 1514) may further be configured to generate a channel usage permission response frame including information indicating the determination. The wireless transmitter 1502 may, during operation, transmit the channel usage permission response frame to the communication device configured to communicate with the other communication device based on the determination on a direct link on the second channel.

[0072] The frequency adjustment database may be, for example, an AFC database. The channel usage permission response frame may further include information indicating a maximum transmission power level and a valid period for using the second channel, and the communication between the communication device and the other communication device on the direct link stops when the valid period expires.

[0073] Also, the circuit 1514 (for example, at least one transmission signal generation unit 1508 of the circuit 1514) may further be configured to generate a stop operation instruction frame. The wireless transmitter 1502 may further be configured to transmit the generated stop operation instruction to the communication device to instruct the stop of communication on the direct link.

[0074] Further, the circuit 1514 (for example, at least one transmission signal generation unit 1508 of the circuit 1514) may be further configured to generate a trigger frame including information for identifying the other communication device, and the wireless transmitter 1502 may be further configured to transmit the generated trigger frame to the communication device. After receiving the trigger frame, the communication device is configured to transmit one or more data frames to the other communication device on the direct link. The trigger frame may be, for example, a TDLS (TDLS Trigger) trigger frame.

[0075] For example, the communication device 1500 may be an AP configured to wirelessly communicate with a communication device. The wireless receiver 1504 may receive, during operation, a TDLS RTS frame including information indicating another communication device and requesting a TXOP for TDLS transmission with the other communication device from the communication device. The circuit 1514 (for example, at least one transmission signal generation unit 1508 of the circuit 1514) may generate a TDLS CTS frame during operation. The wireless transmitter 1502 may transmit the TDLS CTS frame to the communication device during operation. After receiving the TDLS CTS frame, the communication device is configured to transmit one or more data frames to the other communication device on the TDLS direct link within the requested TXOP.

[0076] FIG. 16 is a diagram 1600 showing the flow of a communication method according to various embodiments. In step 1602, a channel usage permission request frame including information indicating a communication device, another communication device, and a second channel different from a first channel may be generated. In step 1604, the generated channel usage permission request frame may be transmitted to the AP in order to request the AP for permission to use the second channel for direct link communication with the other communication device. In step 1606, a channel usage permission response frame permitting the use of the second channel may be received from the AP. In step 1608, after receiving the channel usage permission response frame, communication with the other communication device may be started on a direct link on the second channel.

[0077] FIG. 17 is a diagram showing the configuration of a communication device 1700, for example, a communication device such as a STA, according to various embodiments. Similar to the schematic example of the communication device shown in FIG. 15, the communication device 1700 in the schematic example of FIG. 17 includes at least one antenna 1702 having at least one wireless transmitter and at least one wireless receiver (for simplicity, the wireless transmitter and receiver are not depicted in FIG. 17), and a circuit 1704. The circuit 1704 may include at least one control unit or CPU 1706, and the CPU 1706 is used when executing tasks (including control of communication with other communication devices such as other STAs or APs) designed to be executed with the support of software and hardware.

[0078] Circuit 1704 may further include a positioning module 1708 that determines the position of communication device 1700, which may include latitude and longitude information of its own geolocation position. In some regulated areas, the location information may be used by the AFC system to determine the frequency channels that can be used by the STA for direct link communication. Circuit 1704 may further include a channel selection module 1710 that selects channels used for direct links with other STAs and tracks the channel usage duration of each channel. Further, the module may process the channel usage permission response from the associated AP regarding the channel usage for the direct link. Circuit 1704 may further include a direct link record module 1712 that holds related information regarding the direct link and the corresponding traffic, such as the channel assigned to the direct link and its duration, the traffic stream parameters assigned to the direct link, the buffer status of various direct links, and other similar data.

[0079] FIG. 18 is a diagram showing the configuration of a communication device 1800, such as an AP, according to various embodiments. Similar to the schematic example of the communication device as shown in FIG. 15, the communication device 1800 in the schematic example of FIG. 18 includes at least one antenna 1802 having at least one wireless transmitter and at least one wireless receiver (for simplicity, the wireless transmitter and receiver are not depicted in FIG. 18), and a circuit 1804. Circuit 1804 may include at least one control unit or CPU 1806, and the CPU 1806 is used when executing tasks designed to be executed (including control of communication with other communication devices such as STAs or other APs) under software and hardware support.

[0080] Circuit 1804 may further include an AFC system interface module 1814 that holds information necessary for communicating with the AFC system and operates as a gateway to the AFC system and the AFC database. The actual communication with the AFC system may be via a wired interface. Circuit 1804 may further include a positioning module 1808 that determines the position of the AP device, which may include the latitude and longitude information of the geolocation position of the AP, as well as the position and orientation of the AP from the ground. The position information may be used by the AFC system to determine the frequency channels that can be used by the AP and the STAs associated with the AP. Circuit 1804 may further include a channel management module 1810 that manages the channels used by the STAs associated with the AP (which may include transmitting activation signals on the channels, tracking the channel usage duration, etc.). Also, the module may process channel usage permission requests from the associated STAs regarding the use of channels for direct links and cooperate with the AFC system interface module. Circuit 1804 may further include a direct link record module 1812 that holds related information regarding the direct link and the corresponding traffic, such as the channel assigned to the direct link and its validity period, the traffic stream parameters assigned to the direct link, the buffer status of various direct links, and other similar data.

[0081] FIG. 19 is a diagram showing the configuration of a multi-band device, such as an STA, according to various embodiments. The multi-band device may be said to be composed of a plurality of STAs, each corresponding to a respective frequency band. For example, when the multi-band device supports the 5 GHz band and the 6 GHz band, it may appear to include a 5 GHz STA (such as STA1902) and a 6 GHz STA (such as STA1904), each having a MAC layer and a PHY layer, as well as associated entities. Each STA may have a terminal management entity that can access the MAC layer and PHY layer of each band via its respective MLME (MAC Layer Management Entity) and PLME (PHY Management Entity). The MAC SAP (Service Access Point) of each STA provides an interface to the upper-layer protocol to the band-specific MAC sublayer and PHY sublayer. In a conventional 802.11 network, even if both the AP device and the non-AP device are multi-band devices, they are regarded as separate STAs on each frequency band, and it is required that the 5 GHz non-AP STA be associated with the 5 GHz AP STA and the 6 GHz non-AP STA be associated with the 6 GHz AP STA. In a scenario where the AP is a single-band device (e.g., an 802.11ac AP) and operates only in the 5 GHz band, the non-AP device may not be able to use its 6 GHz STA for communication with the AP. However, two such non-AP devices can communicate in the 6 GHz band by establishing a TDLS link between the corresponding 6 GHz STAs. In such a case, the 5 GHz non-AP STA can request the AP to permit the use of a 6 GHz band channel for direct link communication with another 6 GHz STA instead of the 6 GHz STA. If the MAC address used by the 6 GHz STA is different from the MAC address used by the 5 GHz STA, the AP may maintain a record of the 6 GHz MAC address to track the direct link.

[0082] EHT APs and most EHT non-AP STAs are required to be multi-band devices that support operation in multiple frequency bands. Conventionally, each frequency band has its own MAC layer, PHY layer, and associated entities, and in 802.11, even if contained within the same physical device, the entities associated with each frequency band are treated as separate STAs. Alternatively, regardless of the number of frequency bands in which a multi-band device can operate, each device may be represented by a single unified MAC address and various communication links on different frequencies distinguished by a band ID and channel number.

[0083] Thus, embodiments of the present disclosure provide an advanced communication system, communication method, and communication device that enable extended direct link communication. Although most of the cited examples in the present disclosure relate to IEEE 802.11 networks and devices, the present disclosure can be similarly applied to cellular systems for D2D communication (device-to-device communication) in, for example, LTE-Advanced networks or future 5G networks. Before starting direct link communication in a 6 GHz band channel between two cellular UEs (User Equipment), a UE can request channel usage permission from a serving base station (e.g., an eNodeB) for D2D communication with other nearby UEs by sending a channel usage permission request to the base station. When the base station receives a channel usage permission request from the UE, it checks the AFC database regarding the availability of the requested channel (e.g., via an AFC system). If successful, the base station can send a channel usage permission response including a SUCCESS status to the UE to notify that the requested channel is available for D2D communication. Then, the UE can start using the channel for D2D communication with other UEs.

[0084] The present disclosure can be implemented by software, hardware, or software in cooperation with hardware. Each functional block used in the description of the above embodiments is realized, partially or wholly, as an LSI (Large Scale Integration) which is an integrated circuit, and each process described in the above embodiments may be controlled, partially or wholly, by one LSI or a combination of LSIs. The LSI may be composed of individual chips, or may be composed of one chip so as to include a part or all of the functional blocks. The LSI may be provided with data input and output. Depending on the degree of integration, the LSI may also be referred to as an IC (Integrated Circuit), a system LSI, a super LSI, or an ultra LSI. The technique of integrating into an integrated circuit is not limited to LSI, and may be realized by an application specific circuit, a general-purpose processor, or a dedicated processor. Also, after manufacturing the LSI, an FPGA (Field Programmable Gate Array) which can be programmed, or a reconfigurable processor which can reconfigure the connection and setting of circuit cells inside the LSI may be used. The present disclosure may be realized as digital processing or analog processing. Furthermore, if an integrated circuit technology replacing the LSI appears due to the progress of semiconductor technology or another derived technology, naturally, the integration of functional blocks may be performed using that technology. The application of biotechnology and the like are possible as examples.

[0085] The present disclosure can be implemented in any type of device, apparatus, system having a communication function (collectively referred to as a communication device).

[0086] The communication device may include a wireless transceiver (transceiver) and a processing / control circuit. The wireless transceiver may include a receiver and a transmitter, or may include them as functions. The wireless transceiver (transmitter, receiver) may include an RF (Radio Frequency) module and one or more antennas. The RF module may include an amplifier, an RF modulator / demodulator, or the like.

[0087] Non-limiting examples of communication devices include telephones (such as mobile phones, smartphones, etc.), tablets, personal computers (PCs) (such as laptops, desktops, notebooks, etc.), cameras (such as digital still / video cameras, etc.), digital players (such as digital audio / video players, etc.), wearable devices (such as wearable cameras, smartwatches, tracking devices, etc.), game consoles, digital book readers, telehealth / telemedicine (remote healthcare / medical prescription) devices, vehicles or mobile transportation means with communication functions (such as automobiles, airplanes, ships, etc.), and combinations of the various devices described above.

[0088] The communication device is not limited to portable or mobile ones, and includes all kinds of devices, devices, systems that cannot be carried or are fixed, such as smart home devices (home appliances, lighting devices, smart meters or measuring devices, control panels, etc.), vending machines, and all "Things" that can exist on other IoT (Internet of Things) networks.

[0089] Communication includes data communication by cellular systems, wireless LAN systems, communication satellite systems, etc., as well as data communication by combinations of these.

[0090] In addition, the communication device also includes devices such as controllers and sensors that are connected or linked to a communication device that executes the communication function described in this disclosure. For example, controllers and sensors that generate control signals and data signals used by the communication device that executes the communication function of the communication device are included.

[0091] In addition, the communication device also includes infrastructure facilities, such as base stations, access points, and all other devices, devices, and systems that communicate with or control the various non-limiting devices described above.

[0092] Although some features of various embodiments are described with reference to a device, the corresponding features also apply to the methods of the various embodiments, and vice versa.

[0093] As shown in certain embodiments, it will be understood by those skilled in the art that many changes and / or modifications may be made to the present disclosure without departing from the spirit or scope of the present disclosure as broadly described. Accordingly, the embodiments herein are considered to be illustrative in all respects and not restrictive of the invention.

Claims

1. A receiver that receives one trigger frame from the access point at a transmission opportunity (TXOP) obtained by the access point; A transmitter that transmits a plurality of data frames, each based on information included in the one trigger frame, to another station at different times within a part of the TXOP; and The receiver does not receive a trigger frame within the part of the TXOP; A station.

2. The other station is a peer station that is peer-to-peer linked to the station; The station according to Claim 1.

3. The receiver receives a block acknowledgment frame from the other station within the TXOP; The station according to Claim 1.

4. The plurality of data frames are transmitted with a transmission power lower than a predetermined transmission power level; The station according to Claim 1.

5. A communication method executed by a station, including: Receiving one trigger frame from the access point at a transmission opportunity (TXOP) obtained by the access point; and Transmitting a plurality of data frames, each based on information included in the one trigger frame, to another station at different times within a part of the TXOP, including not receiving a trigger frame within the part of the TXOP. A communication method.

6. An integrated circuit for a station, including: A process of receiving one trigger frame from the access point at a transmission opportunity (TXOP) obtained by the access point; and A process of controlling a process of transmitting a plurality of data frames, each based on information included in the one trigger frame, to another station at different times within a part of the TXOP, including not receiving a trigger frame within the part of the TXOP. An integrated circuit.

7. The trigger frame includes only one User Info field addressed to an individual station; The station according to Claim 1.

8. The trigger frame includes a User Info field addressed to the station, and the User Info field includes an AID 12 subfield in which the AID of the station is set; The station according to claim 1.

9. Some of the plurality of data frames are transmitted without an immediately preceding trigger frame. The station according to claim 1.

10. The plurality of data frames are transmitted by scheduled transmission. The station according to claim 1.

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