Wireless communication device and wireless communication method

Abstract

The present invention provides a wireless communication device. Accordingly, the present invention also provides a wireless communication method. A wireless communication device includes a transmitting circuit and a control circuit, wherein the control circuit sets a request to send (RTS) frame and controls the transmitting circuit to send the RTS frame through at least one channel, and the at least one channel does not include a leading puncturing channel. Another wireless communication device includes a transmitting circuit and a control circuit, wherein the control circuit sets the RTS frame and controls the transmitting circuit to send the RTS frame through multiple channels including the leading puncturing channel.

Description

Technical Field

[0001] The present invention relates to wireless communication, and more particularly, to a wireless communication method and device for setting a protection frame to protect the transmission of a preamble punctured physical layer protocol data unit (PPDU). Background Art

[0002] For channel bonding, IEEE 802.11ac supports multiple bandwidth modes: 20 / 40 / 80 / 160 (80+80) megahertz (MHz). However, except for the 80+80MHz mode, all other modes require the bonded channels to be continuous. As a result, when multiple idle channels are separated by busy channels, it is impossible to bond a larger channel bandwidth. Therefore, the preamble puncturing mechanism is introduced in IEEE 802.11ax, allowing channels to be bonded in a non-contiguous manner. This increases the available bandwidth while improving the transmission rate. For example, when a portion of the 20MHz sub-channels in the secondary channels of the channel bandwidth are busy, the access point (AP) is allowed to transmit a high efficiency (HE) PPDU in a punctured 80 or 160 (80+80) MHz format. Preamble puncturing is an optional function for both AP and STA. In preamble puncturing mode, in a busy 20MHz channel (also called preamble punctured channel), the preamble part will be punctured, which means it will not be transmitted. However, the IEEE 802.11ax specification only addresses preamble puncturing for high-efficiency (HE) PPDUs. Summary of the invention

[0003] One of the purposes of the present invention is to provide a method and apparatus for setting a protection frame to protect the transmission of a physical layer protocol data unit (PPDU) with a leading puncturing. For example, the protection frame may include a request to send (RTS) frame and a clear to send (CTS) frame.

[0004] According to a first aspect of the present invention, an example wireless communication device is provided. The example wireless communication device includes a transmitting circuit and a control circuit. The control circuit is arranged to set a request to send (RTS) frame and control the transmitting circuit to send the RTS frame via at least one channel that does not include a preamble punctured channel. In an embodiment of the present invention, the preamble punctured channel refers to a channel on which a PPDU is not transmitted, for example, Figure 3 The secondary channel indicated by the slashed box has a channel status of busy.

[0005] According to a second aspect of the present invention, an exemplary wireless communication method is provided. The exemplary wireless communication method includes: setting a request to send (RTS) frame, and a transmitting circuit transmitting the RTS frame through at least one channel that does not include a leading puncturing channel.

[0006] According to a third aspect of the present invention, an example wireless communication device is provided. The example wireless communication device includes a transmitting circuit and a control circuit. The control circuit is arranged to set a request to send (RTS) frame and control the transmitting circuit to send the RTS frame via multiple channels including a leading puncturing channel.

[0007] Those skilled in the art will no doubt understand these and other objects of the present invention after reading the following detailed description of the preferred embodiments shown in the accompanying drawings. The detailed description will be given in the following embodiments with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The present invention may be more fully understood by reading the following detailed description and by referring to the examples given in the accompanying drawings, in which:

[0009] Figure 1 FIG. 4 is a schematic diagram of a wireless fidelity (WiFi) communication system according to an embodiment of the present invention.

[0010] Figure 2 According to an embodiment of the present invention, Figure 1 Schematic diagram of wireless communication between wireless communication devices shown in .

[0011] Figure 3 FIG. 4 is a schematic diagram of a first RTS / CTS solution according to an embodiment of the present invention.

[0012] Figure 4 is a schematic diagram of a second RTS / CTS solution according to an embodiment of the present invention.

[0013] Figure 5is a schematic diagram of a third RTS / CTS solution according to an embodiment of the present invention.

[0014] Figure 6 is a schematic diagram of a fourth RTS / CTS scheme according to an embodiment of the present invention.

[0015] Figure 7 is a schematic diagram showing possible settings of the RU allocation subfield in the MU-RTS frame.

[0016] Figure 8 4 is a schematic diagram showing a rule for RU allocation subfields in a MU-RTS frame for preamble puncturing according to an embodiment of the present invention.

[0017] Fig. 9 FIG. 4 is a schematic diagram showing a rule of an RU allocation subfield in a MU-RTS frame for preamble puncturing according to another embodiment of the present invention.

[0018] Fig.10 FIG. 4 is a schematic diagram showing a rule of an RU allocation subfield in a MU-RTS frame for preamble puncturing according to yet another embodiment of the present invention.

[0019] In the following detailed description, for the purpose of illustration, many specific details are set forth so that those skilled in the art can more thoroughly understand the embodiments of the present invention. However, it is apparent that one or more embodiments may be implemented without these specific details, and different embodiments may be combined as needed, and should not be limited to the embodiments listed in the accompanying drawings. DETAILED DESCRIPTION

[0020] The following description is a preferred embodiment of the present invention, which is only used to illustrate the technical features of the present invention, and is not used to limit the scope of the present invention. Certain words are used throughout the specification and claims to refer to specific components. It should be understood by those skilled in the art that manufacturers may use different names to refer to the same components. Therefore, the present specification and claims do not use the difference in name as a way to distinguish components, but use the difference in function of the components as a basis for distinction. The terms "component", "system" and "device" used in the present invention can be entities related to computers, wherein the computer can be hardware, software, or a combination of hardware and software. The terms "including" and "comprising" mentioned in the following description and claims are open-ended terms, so they should be interpreted as "including, but not limited to...". In addition, the term "coupled" means an indirect or direct electrical connection. Therefore, if a device is described as coupled to another device, it means that the device can be directly electrically connected to the other device, or indirectly electrically connected to the other device through other devices or connection means.

[0021] Corresponding numbers and symbols in the various figures of the drawings generally refer to corresponding parts unless otherwise indicated. The drawings are drawn to clearly illustrate the relevant parts of the embodiments and are not necessarily drawn to scale.

[0022] Figure 1 1 is a schematic diagram of a wireless fidelity (WiFi) communication system according to an embodiment of the present invention. The WiFi communication system 100 has multiple wireless communication devices 102 and 104, including access points (APs) and non-AP stations (STAs). For example, the wireless communication device 102 may be an AP, and the wireless communication device 104 may be a non-AP station (STA). For another example, the wireless communication device 102 may be a non-AP STA, and the wireless communication device 104 may be an AP. For the sake of simplicity, Figure 1 Only two wireless communication devices are shown. In practice, the WiFi communication system 100 allows for more than two wireless communication devices, including one AP and more than one non-AP STA in the same basic service set (BSS). As an example and not a limitation, the wireless communication devices 102 and 104 comply with IEEE 802.11ax, IEEE802.11be standards and / or other prior standards, such as IEEE 802.11b, 802.11g, 802.11a, 802.11n, 802.11ac, and specifically, the embodiments of the present invention are not limited thereto.

[0023] like Figure 1 As shown, the wireless communication device 102 includes a processor 112, a memory 114, a control circuit 116, a transmitter (TX) circuit 118, and a receiver (RX) circuit 120. The memory 114 is arranged to store program code. The processor 112 is used to load and execute the program code to manage the wireless communication device 102. The control circuit 116 is used to control wireless communication with the wireless communication device 104. In the case where the wireless communication device 102 is an AP and the wireless communication device 104 is a non-AP STA, the control circuit 116 controls the TX circuit 118 to deal with downlink (DL) traffic between the AP and the non-AP STA, and controls the RX circuit 120 to deal with uplink (UL) traffic between the AP and the non-AP STA. In another case where wireless communication device 102 is a non-AP STA and wireless communication device 104 is an AP, control circuit 116 controls TX circuit 118 to process UL traffic between the non-AP and the AP, and controls RX circuit 120 to process DL traffic between the non-AP STA and the AP.

[0024] In a wireless network, there are a large number of mobile nodes that share a communication medium. Wireless networks use carrier sensing-based algorithms, such as Carrier Sensing Multiple Access (CSMA) and CSMA with Collision Avoidance (CSMA / CA), to effectively share communication channels. However, this approach does not address the problem of hidden nodes. Hidden nodes are those nodes that are beyond the range of other nodes or a group of nodes. Network throughput is reduced due to packet collisions caused by these hidden nodes. To address the hidden node problem, request to send (RTS) and clear to send (CTS) mechanisms are widely used in wireless networks to reserve a channel for transmitting data from a sender to a receiver. For example, a sender sends an RTS frame with a network allocation vector (NAV) setting to a receiver, and the receiver responds with a CTS frame with an updated NAV setting. All neighboring STAs on the same channel will hear the RTS, CTS, or both, and will update their NAV timers and defer their own transmissions on that channel.

[0025] To improve channel utilization, when a portion of the channel bandwidth is busy, the wireless communication device 102 sends the HE PPDU in a punctured 80 or 160 (80+80) MHz format. Figure 3 For example, Figure 3The channel bandwidth shown is 80MHz, and the 80MHz channel bandwidth is composed of 1 20MHz main channel and 3 20MHz secondary channels, wherein the box shown with slashes indicates that the PPDU is not transmitted on the channel in the channel bandwidth. In an embodiment of the present invention, the channel is called a preamble puncturing channel, and the other channels are channels that are not preamble punctured. The punctured 80MHz means that at least one of the 4 20MHz channels included in the channel bandwidth is a preamble puncturing channel, and the PPDU is transmitted on other channels that do not include the preamble puncturing channel. In an embodiment of the present invention, the PPDU transmitted in this way (or, the PPDU is transmitted on non-continuous channels in the channel bandwidth) is called a preamble punctured PPDU. In one embodiment of the present invention, the preamble punctured HE PPDU is a HE single-user (SU) PPDU. In another embodiment, the preamble punctured HE PPDU is a HE multi-user (MU) PPDU. The present invention proposes several RTS / CTS schemes to protect the transmission of the HE PPDU with punctured preamble.

[0026] Figure 2 According to the embodiment of the present invention Figure 1 Schematic diagram of wireless communication between wireless communication devices 102 and 104 shown. The wireless communication device 102 may send an RTS frame to the wireless communication device 104. After receiving the RTS frame, the wireless communication device 104 responds with a CTS frame. After receiving the CTS frame, the wireless communication device 102 sends a preamble punctured HE PPDU to the wireless communication device 104, or in other words, sends the HE PPDU using the preamble puncturing mechanism. After successfully receiving the preamble punctured HE PPDU, the wireless communication device 104 sends an acknowledgment (ACK) frame to the wireless communication device 102. In the case where the wireless communication device 102 is an AP, the RTS frame may be a multi-user request to send (MU-RTS) frame, and the preamble punctured HE PPDU may be a preamble punctured HE MU PPDU. Compared with the traditional RTS / CTS design, the present invention proposes bandwidth adaptation and / or preamble puncturing for these protection frames (e.g., RTS frame, CTS frame).

[0027] Figure 31 is a schematic diagram of a first RTS / CTS scheme according to an embodiment of the present invention. Assume that the PPDU with preamble puncturing will be transmitted in an 80MHz channel bandwidth using preamble puncturing, which includes a primary 20MHz channel, a secondary 20MHz channel with preamble puncturing, and a secondary 40MHz channel consisting of two consecutive 20MHz channels. The control circuit 116 is used to set the RTS frame and control the TX circuit 118 to transmit the preamble punctured channel (for example, Figure 3 The RTS frame is sent via multiple channels (sub-20 MHz channels with slashes shown). More specifically, the multiple channels on which the RTS frame is sent include the leading punctured channel and all channels of the PPDU of the leading punctured that are not punctured by the leading. The wireless communication device 104 detects the non-punctured bandwidth pattern (i.e., non-punctured resource unit (RU) allocation) of the RTS frame sent from the wireless communication device 102, and generates a CTS frame in response to the RTS frame, wherein the CTS frame has the same non-punctured bandwidth pattern (i.e., non-punctured RU allocation) as the RTS frame. Therefore, the RX circuit 120 receives the CTS frame transmitted via the multiple channels, the multiple channels including the leading punctured channel and all channels of the PPDU of the leading punctured that are not punctured by the leading. However, if the RTS frame is a MU-RTS frame, the CTS bandwidth can be specified in the MU-RTS frame. In short, the first RTS / CTS scheme uses RTS frames and CTS frames, each of which has a non-punctured bandwidth mode (ie, non-punctured RU allocation) to achieve protection of the full 80 MHz bandwidth covering the leading punctured channel.

[0028] Figure 4 1 is a schematic diagram of a second RTS / CTS scheme according to an embodiment of the present invention. Assume that the PPDU with preamble puncturing will be transmitted in an 80MHz channel bandwidth with preamble puncturing, which includes a primary 20MHz channel, a secondary 20MHz channel punctured by the preamble, and a secondary 40MHz channel consisting of two consecutive 20MHz channels. The control circuit 116 is used to set the RTS frame and control the TX circuit 118 to transmit only through the primary channel (e.g., Figure 4 The primary 20 MHz channel shown in FIG. 1 transmits an RTS frame, wherein the primary channel is not a leading puncturing channel (e.g., a leading puncturing channel such as Figure 4The wireless communication device 104 detects the non-punctured bandwidth pattern (i.e., non-punctured RU allocation) of the RTS frame sent by the wireless communication device 102, and generates a CTS frame in response to the RTS frame, wherein the CTS frame has the same non-punctured bandwidth pattern (i.e., non-punctured RU allocation) as the RTS frame. In this embodiment, the RX circuit 120 transmits the data to the wireless communication device 104 only through the primary channel (e.g., Figure 4 In the embodiment of the present invention, the CTS frame transmitted by the primary 20MHz channel (as shown in FIG. 1 ) is received by the RTS frame. However, if the RTS frame is a MU-RTS frame, the CTS bandwidth can be specified in the MU-RTS frame. In short, the second RTS / CTS scheme uses an RTS frame only on the primary channel and a CTS frame only on the primary channel to achieve protection of a portion of the bandwidth covering only the primary channel (e.g., the primary 20MHz / 40MHz / 80MHz channel).

[0029] Figure 5 1 is a schematic diagram of a third RTS / CTS scheme according to an embodiment of the present invention. Assume that the PPDU with preamble puncturing will be transmitted in an 80MHz channel with preamble puncturing, which includes a primary 20MHz channel, a secondary 20MHz channel punctured by the preamble, and a secondary 40MHz channel consisting of two consecutive 20MHz channels. The control circuit 116 is used to set the RTS frame and control the TX circuit 118 to exclude the preamble puncturing channel (e.g., Figure 5The RTS frame is sent on multiple channels (sub-20 MHz channels with slashes shown). More specifically, the channels on which the RTS frame is sent include all channels of the preamble punctured PPDU that are not preamble punctured (all channels of the preamble punctured PPDU that are not preamble punctured). In this embodiment, the wireless communication device 104 has the ability to detect the punctured bandwidth pattern (i.e., punctured RU allocation) of the RTS frame transmitted by the wireless communication device 102. The wireless communication device 104 generates a CTS frame as a response to the RTS frame, wherein the CTS frame has the same punctured bandwidth pattern (i.e., punctured RU allocation) as the RTS frame. Therefore, the RX circuit 120 receives the transmitted CTS frame through the multiple channels (which do not include the preamble punctured channel but include all channels of the preamble punctured PPDU that are not preamble punctured). However, if the RTS frame is a MU-RTS frame, the CTS bandwidth can be specified in the MU-RTS frame. In brief, the third RTS / CTS scheme uses RTS frames and CTS frames each having a punctured bandwidth mode (ie, punctured RU allocation) to achieve the same bandwidth protection as the leading punctured PPDU.

[0030] Figure 6 1 is a schematic diagram of a fourth RTS / CTS scheme according to an embodiment of the present invention. Assume that the PPDU with preamble puncturing will be transmitted in an 80MHz channel with preamble puncturing, which includes a primary 20MHz channel, a secondary 20MHz channel punctured by the preamble, and a secondary 40MHz channel consisting of two consecutive 20MHz channels. The control circuit 116 is used to set the RTS frame and control the TX circuit 118 to exclude the preamble puncturing channel (e.g., Figure 6The RTS frame is sent on multiple channels (the secondary 20 MHz channels with slashes shown). More specifically, the channels on which the RTS frame is sent include all channels of the PPDU of the leading punctured frame that are not punctured by the leading punctured frame. In this embodiment, the wireless communication device 104 does not have the ability to detect the punctured bandwidth pattern (i.e., punctured RU allocation) of the RTS frame sent by the wireless communication device 102. The wireless communication device 104 generates a CTS frame in response to the RTS frame, wherein the CTS frame does not have the same punctured bandwidth pattern (i.e., punctured RU allocation) as the RTS frame. Instead, the wireless communication device 104 sends the CTS frame only through the detected continuous bandwidth. Therefore, the CTS frame has a modified RU allocation that is inconsistent with the punctured bandwidth pattern (i.e., punctured RU allocation) of the RTS frame and only includes the detected continuous bandwidth. For example, the wireless communication device 104 only transmits the CTS frame via the primary channel (e.g., Figure 6 The fourth RTS / CTS scheme uses an RTS frame with a punctured bandwidth mode (i.e., punctured RU allocation) and a CTS frame with a continuous bandwidth mode (i.e., modified RU allocation) to protect the same bandwidth as the leading punctured PPDU.

[0031] The main purpose of using the RTS / CTS mechanism is to reserve the channel and enhance the virtual carrier sensing process. That is, the RTS / CTS mechanism enables all other non-AP STAs to update their virtual carriers (i.e., NAV) so that they can postpone any transmission from the channel during the transmission opportunity (TXOP) and get rid of the hidden node problem. The 802.11ax specification has a variant of RTS, called MU-RTS. When the wireless communication device 102 is an AP, it can send a MU-RTS frame to multiple users (i.e., non-AP STAs, including the wireless communication device 104), wherein the MU-RTS frame includes a common information field (Common Info field) for all users and a user information field (User Info field) for each user (i.e., non-AP STA, including the wireless communication device 104). After receiving the MU-RTS frame, each user (i.e., non-AP STA, including the wireless communication device 104) replies a CTS frame to the AP (i.e., the wireless communication device 102).

[0032] Regarding the protection of the HE MU PPDU with preamble puncturing, the present invention also proposes rules for certain subfields in the MU-RTS frame with preamble puncturing. For example, the resource unit (RU) allocation subfield in a user information field for each of the association identifiers (AIDs) for non-AP STAs and the uplink bandwidth (ULBW) subfield in the common information field should be set according to the clear channel assessment (CCA) state.

[0033] Figure 7 is a schematic diagram showing possible settings of the RU Allocation subfield in the MU-RTS frame. The RU Allocation subfield is set to the following values ​​to indicate the primary 20 MHz channel, as shown below:

[0034] - If the primary 20 MHz channel is the only 20 MHz channel (for example, the bandwidth is 20 MHz) or the lowest frequency 20 MHz channel (for example, the bandwidth is 80 MHz, but the primary 20 MHz channel is the lowest frequency 20 MHz channel within the 80 MHz bandwidth), then 61;

[0035] - 62 if the primary 20 MHz channel is the second lowest frequency 20 MHz channel in the 40 MHz bandwidth or the 80 MHz bandwidth;

[0036] - 63 if the primary 20 MHz channel is the third lowest frequency 20 MHz channel in the 80 MHz bandwidth; and,

[0037] —64 if the primary 20 MHz channel is the fourth lowest frequency 20 MHz channel in the 80 MHz bandwidth.

[0038] The RU Allocation subfield is set to the following values ​​to indicate the primary 40 MHz channel, as shown below:

[0039] - 65 if the primary 40 MHz channel is the only 40 MHz channel or the lowest frequency 40 MHz channel among the 80 MHz channels; and,

[0040] —If the primary 40 MHz channel is the second lowest frequency 40 MHz channel among the 80 MHz channels, then it is 66.

[0041] The RU Allocation subfield is set to 67 to indicate a primary 80 MHz channel, for example, the primary 80 MHz is the only 80 MHz channel, or the primary 80 MHz is the lowest frequency 80 MHz in the 160 MHz bandwidth. The RU Allocation subfield is set to 68 to indicate a primary 80 MHz channel and a secondary 80 MHz channel.

[0042] When a busy channel is regarded as a leading puncturing channel (for example, when the channel state of a certain channel within the channel bandwidth is CCA busy, the channel can be regarded as a leading puncturing channel, otherwise, it can be regarded as a non-leading puncturing channel), the control circuit 116 imposes constraints on the setting of the RU allocation subfield. In an exemplary design, the RU allocation subfield is set to indicate on which main channel the CTS frame is sent, and the control circuit 116 is used to set the RU allocation subfield by deleting / removing or modifying the original RU allocation subfield value, wherein the original RU allocation subfield value indicates the main channel overlapping with the leading puncturing channel. For example, when the third lowest 20MHz channel is preamble punctured, the original RU allocation value 67 in the MU-RTS frame is deleted, or the original RU allocation value 67 in the MU-RTS frame is modified / reallocated to 65. For better understanding, several examples are provided below.

[0043] Please combine Figure 8 refer to Figure 7 , Figure 8 1 is a schematic diagram of the rule of the RU allocation subfield (denoted by "ruAlloc") in the MU-RTS frame for preamble puncturing according to an embodiment of the present invention. Assume that an 80MHz HEMU PPDU will be sent using preamble puncturing. It should be noted that the primary channel is not allowed to be punctured by the preamble.

[0044] For the first case where the primary 20 MHz channel is the lowest frequency 20 MHz channel within the 80 MHz bandwidth ( Figure 8In the figure, marked as "Main 20@1000", when the second lowest 20MHz channel is preamble punctured due to its channel status "CCA Busy", the main channel on which the CTS frame should be sent is limited to the main channel indicated by the RU allocation subfield ruAlloc=61 (ruAlloc=65, 67, 68 are deleted); when the third lowest 20MHz channel is preamble punctured due to its channel status "CCA Busy", it is limited to the main channel indicated by ruAlloc=61 or ruAlloc=65 (ruAlloc=67, 68 are deleted), and, when the fourth lowest 20MHz channel is preamble punctured due to its channel status "CCA Busy", it is limited to the main channel indicated by ruAlloc=61 or ruAlloc=65 (ruAlloc=67, 68 are deleted).

[0045] For the second case where the primary 20 MHz channel is the second lowest frequency 20 MHz channel within the 80 MHz bandwidth ( Figure 8 In the figure, marked as "Main 20@0100"), when the lowest 20MHz channel is preamble punctured due to its channel status "CCA Busy", the main channel on which the CTS frame should be sent is limited to the main channel indicated by the RU allocation subfield ruAlloc=62 (ruAlloc=65, 67, 68 are deleted); when the third lowest 20MHz channel is preamble punctured due to its channel status "CCA Busy", it is limited to the main channel indicated by ruAlloc=62 or ruAlloc=65 (ruAlloc=67, 68 are deleted); and, when the fourth lowest 20MHz channel is preamble punctured due to its channel status "CCABusy", it is limited to the main channel indicated by ruAlloc=62 or ruAlloc=65 (ruAlloc=67, 68 are deleted).

[0046] Regarding the third case where the primary 20 MHz channel is the third lowest frequency 20 MHz channel in the 80 MHz bandwidth ( Figure 8In the figure, marked as "Main 20@0010", when the lowest 20MHz channel is preamble punctured due to its channel state "CCABusy", the main channel on which the CTS frame should be sent is limited to the main channel indicated by ruAlloc=63 or ruAlloc=66 (ruAlloc=67,68 are deleted); when the second lowest 20MHz channel is preamble punctured due to its channel state "CCABusy", it is limited to the main channel indicated by ruAlloc=63 or ruAlloc=66 (ruAlloc=67,68 are deleted); and, when the fourth lowest 20MHz channel is preamble punctured due to its channel state "CCA Busy", it is limited to the main channel indicated by ruAlloc=63 (ruAlloc=66,67,68 are deleted).

[0047] Regarding the fourth case where the primary 20 MHz channel is the fourth lowest frequency 20 MHz channel in the 80 MHz bandwidth ( Figure 8 In the figure, marked as "Main 20@0001", when the lowest 20MHz channel is preamble punctured due to its channel state "CCABusy", the main channel on which the CTS frame should be sent is limited to the main channel indicated by ruAlloc=64 or ruAlloc=66 (ruAlloc=67,68 are deleted); when the second lowest 20MHz channel is preamble punctured due to its channel state "CCA Busy", it is limited to the main channel indicated by ruAlloc=64 or ruAlloc=66 (ruAlloc=67,68 are deleted); and, when the third lowest 20MHz channel is preamble punctured due to its channel state "CCABusy", it is limited to the main channel indicated by ruAlloc=64 (ruAlloc=66,67,68 are deleted).

[0048] In addition, the control circuit 116 is further configured to set the UL BW subfield to indicate the bandwidth of the leading punctured MU-RTS frame (the leading punctured MU-RTS frame is not transmitted using the leading punctured channel). In this embodiment, the UL BW subfield may be set by indicating a value of "60 MHz". In other embodiments, the UL BW subfield may be set by indicating a bandwidth other than "20 MHz", "40 MHz", "80 MHz", "80+80 MHz, or 160 MHz" specified in the 802.11ax specification.

[0049] In another exemplary design, the control circuit 116 is arranged to set the RU allocation subfield to indicate the bandwidth mode of the punctured RU on which the CTS frame is sent. Specifically, the RU allocation value carried by the RU allocation subfield is outside the range {61, 62, 63, 64, 65, 66, 67, 68} to indicate the bandwidth mode of the punctured RU on which the CTS frame should be sent. For example, the RU allocation value carried by the RU allocation subfield is selected from the range {69, 70, 71, 72}. Please refer to Fig. 9 refer to Figure 7 , Fig. 9 FIG. 1 is a schematic diagram of a rule for the RU allocation subfield (denoted by “ruAlloc”) in a MU-RTS frame for preamble puncturing according to another embodiment of the present invention. Assume that an 80MHz HE MU PPDU is to be sent using preamble puncturing. It should be noted that preamble puncturing is not allowed for the primary channel.

[0050] Regarding the first case where the primary 20MHz channel is the lowest frequency 20MHz channel within the 80MHz bandwidth ( Fig. 9 In the figure, it is marked as main 20@1000), when the second lowest 20MHz channel is preamble punctured due to its channel state "CCABusy", the bandwidth mode of the punctured RU on which the CTS frame should be sent is indicated by ruAlloc=69; when the third lowest 20MHz channel is preamble punctured due to its channel state "CCA Busy", it is indicated by ruAlloc=70; when the fourth lowest 20MHz channel is preamble punctured due to its channel state "CCA Busy", it is indicated by ruAlloc=71.

[0051] Regarding the second case where the primary 20 MHz channel is the second lowest frequency 20 MHz channel within the 80 MHz bandwidth ( Fig. 9 In the figure, marked as main 20@0100), when the lowest 20MHz channel is preamble punctured due to its channel status "CCA Busy", the bandwidth mode of the punctured RU on which the CTS frame should be sent is indicated by ruAlloc=72, when the third lowest 20MHz channel is preamble punctured due to its channel status "CCA Busy", it is indicated by ruAlloc=70, and when the fourth lowest 20MHz is preamble punctured due to its channel status "CCABusy", it is indicated by ruAlloc=71.

[0052] Regarding the third case where the primary 20 MHz channel is the third lowest frequency 20 MHz channel in the 80 MHz bandwidth ( Fig. 9In the figure, marked as main 20@0010), when the lowest 20MHz channel is preamble punctured due to its channel status "CCA Busy", the bandwidth mode of the punctured RU on which the CTS frame should be sent is indicated by ruAlloc=72, when the second lowest 20MHz channel is preamble punctured due to its channel status "CCA Busy", it is indicated by ruAlloc=69, and when the fourth lowest 20MHz channel is preamble punctured due to its channel status "CCABusy", it is indicated by ruAlloc=71.

[0053] Regarding the fourth case where the primary 20 MHz channel is the fourth lowest frequency 20 MHz channel in the 80 MHz bandwidth ( Fig. 9 In the figure, marked as main 20@0001), when the lowest 20MHz channel is preamble punctured due to its channel status "CCA Busy", the bandwidth mode of the punctured RU on which the CTS frame should be sent is indicated by ruAlloc=72, when the second lowest 20MHz channel is preamble punctured due to its channel status "CCA Busy", it is indicated by ruAlloc=69, and when the third lowest 20MHz channel is preamble punctured due to its channel status "CCABusy", it is indicated by ruAlloc=71.

[0054] In addition, the control circuit 116 is further configured to set the UL BW subfield to indicate the bandwidth of the leading punctured MU-RTS frame (the leading punctured MU-RTS frame is not transmitted using the leading punctured channel). In this embodiment, the UL BW subfield may be set by indicating a value of "60 MHz". In other embodiments, the UL BW subfield may be set by indicating a bandwidth different from "20 MHz", "40 MHz", "80 MHz", "80+80 MHz or 160 MHz" specified in the 802.11ax specification.

[0055] In addition to setting the MU-RTS frame to be sent using the leading puncturing, the control circuit 116 is also capable of setting the MU-RTS frame to be sent only through the primary channel. In response to the RU allocation subfield set in the user information field for the AID assigned to the non-AP STA, the non-AP STA can reply the CTS frame to the AP only through the primary channel. The primary channel used for CTS frame transmission can be the same as or different from the primary channel used for RTS frame transmission. Similarly, the control circuit 116 is used to set the RU allocation subfield to ensure that the primary channel indicated by the RU allocation subfield does not overlap with the leading puncturing channel.

[0056] Combination Fig.10 refer to Figure 7 , Fig.10FIG. 1 is a schematic diagram of a rule for the RU allocation subfield (denoted by “ruAlloc”) in a MU-RTS frame for preamble puncturing according to another embodiment of the present invention. Assume that an 80 MHz HE MU PPDU is to be sent using preamble puncturing. It should be noted that preamble puncturing is not allowed for the primary channel.

[0057] Regarding the first case where the primary 20 MHz channel used by the AP to send MU-RTS frames is the 20 MHz channel with the lowest frequency within the 80 MHz bandwidth, when the second lowest 20 MHz channel is preamble punctured due to its channel status "CCA Busy", the primary channel on which the CTS frame should be sent is limited to the primary channel indicated by ruAlloc=61 (ruAlloc=65, 67, 68 are deleted); when the third lowest 20 MHz channel is preamble punctured due to its channel status "CCA Busy", it is limited to the primary channel indicated by ruAlloc=61 or ruAlloc=65 (ruAlloc=67, 68 are deleted); and, when the fourth lowest 20 MHz channel is preamble punctured due to its channel status "CCA Busy", it is limited to the primary channel indicated by ruAlloc=61 or ruAlloc=65 (ruAlloc=67, 68 are deleted).

[0058] Regarding the second case where the primary 20 MHz channel used by the AP to send MU-RTS frames is the second lowest frequency 20 MHz channel within the 80 MHz bandwidth, when the lowest 20 MHz channel is preamble punctured due to its channel status "CCA Busy", the primary channel on which the CTS frame should be sent is limited to the primary channel indicated by ruAlloc=62 (ruAlloc=65, 67, 68 are deleted); when the third lowest 20 MHz channel is preamble punctured due to its channel status "CCA Busy", it is limited to the primary channel indicated by ruAlloc=62 or ruAlloc=65 (ruAlloc=67, 68 are deleted); and, when the fourth lowest 20 MHz channel is preamble punctured due to its channel status "CCABusy", it is limited to the primary channel indicated by ruAlloc=62 or ruAlloc=65 (ruAlloc=67, 68 are deleted).

[0059] Regarding the third case where the primary 20 MHz channel used by the AP for sending MU-RTS frames is the third lowest frequency 20 MHz channel within the 80 MHz bandwidth, when the lowest 20 MHz channel is preamble punctured due to its channel status "CCA Busy", the primary channel on which the CTS frame should be sent is limited to the primary channel indicated by ruAlloc=63 or ruAlloc=66 (ruAlloc=67, 68 are deleted); when the second lowest 20 MHz channel is preamble punctured due to its channel status "CCA Busy", it is limited to the primary channel indicated by ruAlloc=63 or ruAlloc=66 (ruAlloc=67, 68 are deleted); and, when the fourth lowest 20 MHz channel is preamble punctured due to its channel status "CCABusy", it is limited to the primary channel indicated by ruAlloc=63 (ruAlloc=66, 67, 68 are deleted).

[0060] Regarding the fourth case where the primary 20 MHz channel used by the AP for sending MU-RTS frames is the fourth lowest frequency 20 MHz channel in the 80 MHz bandwidth, when the lowest 20 MHz channel is preamble punctured due to its channel status "CCA Busy", the primary channel on which the CTS frame should be sent is limited to the primary channel indicated by ruAlloc=64 or ruAlloc=66 (ruAlloc=67, 68 are deleted); when the second lowest 20 MHz channel is preamble punctured due to its channel status "CCA Busy", it is limited to the primary channel indicated by ruAlloc=64 or ruAlloc=66 (ruAlloc=67, 68 are deleted); and, when the third lowest 20 MHz channel is preamble punctured due to its channel status "CCA Busy", it is limited to the primary channel indicated by ruAlloc=64 (ruAlloc=66, 67, 68 are deleted).

[0061] In addition, the control circuit 116 is further configured to set the UL BW subfield to indicate the bandwidth of the preamble punctured MU-RTS frame (which is not transmitted using the preamble punctured channel). In this embodiment, the UL BW subfield may be set by a value indicating "20 MHz" specified in the 802.11ax specification. In other embodiments, the UL BW subfield may be set by a value indicating "40 MHz", "80 MHz" or "80+80 MHz or 160 MHz" specified in the 802.11ax specification.

[0062] In the above embodiments, the proposed RTS / CTS scheme is described in the case where a preamble punctured PPDU (e.g., a preamble punctured HE SU PPDU or a preamble punctured HE MU PPDU) is transmitted using an 80MHz channel with preamble puncturing. However, the same concept of the proposed RTS / CTS scheme can be extended to another scenario where a preamble punctured PPDU (e.g., a preamble punctured HE SU PPDU or a preamble punctured HE MU PPDU) is transmitted using an 80+80MHz channel (or a 160MHz channel) with preamble puncturing. For the sake of brevity, similar descriptions are omitted here.

[0063] Although the present invention has been described by way of example and in terms of preferred embodiments, it should be understood that the present invention is not limited to the disclosed embodiments. Instead, it is intended to cover various modifications and similar structures (as will be apparent to those skilled in the art), for example, combinations or replacements of different features in different embodiments. Therefore, the scope of the appended claims should be given the broadest interpretation to cover all such modifications and similar structures.

Claims

1. A wireless communication device, comprising: Transmitting circuit; A control circuit, configured to set a request to send RTS frame, and control the sending circuit to send the RTS frame via at least one channel not including the preamble puncturing channel, wherein the at least one channel includes all non-preamble punctured channels of a preamble punctured physical layer protocol data unit PPDU; and A receiving circuit is configured to receive a clear-to-send (CTS) frame sent in response to the RTS frame, wherein the CTS frame has a punctured resource unit (RU) allocation, and the CTS frame is transmitted through the same channel as all channels of the preamble punctured PPDU that are not punctured by the preamble.

2. A wireless communication device, characterized in that: The wireless communication device comprises: Transmitting circuit; A control circuit, configured to set a request to send RTS frame, and control the sending circuit to send the RTS frame via at least one channel not including the preamble puncturing channel, wherein the at least one channel includes all non-preamble punctured channels of a preamble punctured physical layer protocol data unit PPDU; and The receiving circuit is configured to receive a clear-to-send (CTS) frame sent in response to the RTS frame, wherein the CTS frame is transmitted using a modified resource unit (RU) allocation, and the modified resource unit (RU) allocation includes only continuous bandwidth.

3. A wireless communication device, characterized in that: The wireless communication device comprises: Transmitting circuit; A control circuit, configured to set a multi-user request to send a MU-RTS frame, and control the sending circuit to send the MU-RTS frame via at least one channel that does not include a leading puncturing channel; The MU-RTS frame includes a resource unit RU allocation subfield, the resource unit RU allocation subfield is used to indicate a primary channel on which a clear to send CTS frame is sent, and the control circuit is used to set the RU allocation subfield by deleting or modifying an original RU allocation subfield value indicating that the primary channel overlaps with the leading puncturing channel; or The MU-RTS frame includes a resource unit RU allocation subfield, and the control circuit is used to set the RU allocation subfield to indicate a bandwidth mode of a punctured RU on which a clear to send CTS frame is sent; or The MU-RTS frame includes an uplink bandwidth UL BW subfield, and the control circuit is used to set the UL BW subfield to indicate the bandwidth of the MU-RTS frame, wherein the MU-RTS frame is not transmitted using the leading puncturing channel.

4. A wireless communication method, comprising: Set the request to send RTS frame; Sending the RTS frame via at least one channel excluding the preamble punctured channel, wherein the at least one channel includes all non-preamble punctured channels of the preamble punctured physical layer protocol data unit PPDU; and A clear-to-send (CTS) frame sent in response to the RTS frame is received, wherein the CTS frame has a punctured resource unit (RU) allocation, and the CTS frame is transmitted through the same channel as all non-preamble punctured channels of the preamble punctured PPDU.

5. A wireless communication method, characterized in that: The wireless communication method comprises: Set the request to send RTS frame; Sending the RTS frame via at least one channel excluding the preamble punctured channel, wherein the at least one channel includes all non-preamble punctured channels of the preamble punctured physical layer protocol data unit PPDU; and A clear to send (CTS) frame sent in response to the RTS frame is received, wherein the CTS frame is transmitted using a modified resource unit (RU) allocation, the modified resource unit (RU) allocation including only contiguous bandwidth.

6. A wireless communication method, characterized in that: The wireless communication method comprises: Set up multi-user request to send MU-RTS frames; sending the MU-RTS frame via at least one channel excluding a leading puncturing channel; The MU-RTS frame includes a resource unit RU allocation subfield, the resource unit RU allocation subfield is used to indicate a primary channel on which a clear to send CTS frame is sent, and setting the MU-RTS frame includes: The RU allocation subfield is set by deleting or modifying the original RU allocation subfield value indicating that the primary channel overlaps with the leading puncturing channel; or The MU-RTS frame includes a resource unit RU allocation subfield, and setting the MU-RTS frame includes: The RU Allocation subfield is set to indicate the bandwidth mode of the punctured RU on which the Clear to Send (CTS) frame is sent; or The MU-RTS frame includes an uplink bandwidth UL BW subfield, and setting the MU-RTS frame includes: The UL BW subfield is set to indicate the bandwidth of the MU-RTS frame, wherein the MU-RTS frame is not transmitted using the preamble puncturing channel.

7. A wireless communication device, comprising: Transmitting circuit; A control circuit, configured to set a request to send RTS frame and control the sending circuit to send the RTS frame via a plurality of channels including a leading puncturing channel; as well as The receiving circuit is configured to receive a clear-to-send (CTS) frame sent in response to the RTS frame, wherein the CTS frame is sent via the plurality of channels including the leading puncturing channel.

8. The wireless communication device according to claim 7, wherein: The plurality of channels include the preamble punctured channel and all channels of the preamble punctured physical layer protocol data unit PPDU that are not preamble punctured.

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