Communication device and communication method for performing control signaling

Abstract

The present disclosure provides a communications apparatus and method for performing control signaling, the communications apparatus comprising: a circuit that, in operation, generates a transmission signal including a first signal field having a first portion and a second portion, each portion including the same number of data bits, wherein the data bits in the second portion of the first signal field do not include version-independent bits;

Description

Technical Field

[0001] The present disclosure relates to a communication apparatus and a communication method for performing control signaling, and more particularly, to a communication apparatus and a communication method for performing control signaling in an EHT WLAN (Extremely High Throughput Wireless Local Area Network).

Background Art

[0002] In the standardization of next-generation Wireless Local Area Networks (WLANs), a new wireless access technology having backward compatibility with IEEE 802.11a / b / g / n / ac / ax technologies has been studied within the IEEE 802.11 working group and is named Extremely High Throughput (EHT) WLAN.

[0003] In EHT WLAN, for the purpose of providing a peak throughput and a large increase in capacity exceeding those of 802.11ax High Efficiency (HE) WLAN, it is desired to expand the maximum channel bandwidth from 160 MHz to 320 MHz, increase the maximum number of spatial streams from 8 to 16, and support multi-band operation. Further, for the purpose of improving spectral efficiency compared to 11ax HE WLAN, it has been proposed to enable preamble puncturing of a Physical Layer Protocol Data Unit (PPDU) transmitted to one communication apparatus.

Prior Art Documents

Non-Patent Documents

[0004]

Non-Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, there has been no discussion so far regarding a communication device and a communication method that perform control signaling, particularly regarding the support for efficient signaling of preamble puncturing of a PPDU transmitted to a single communication device in the context of EHT WLAN.

[0006] Therefore, there is a need for a communication device and a communication method that provide a feasible technical solution for performing control signaling in the context of EHT WLAN. Furthermore, other desirable features and characteristics will become apparent by reading the following detailed description and the appended claims in conjunction with the accompanying drawings and the background art in this specification.

Means for Solving the Problem

[0007] Non-limiting and exemplary embodiments facilitate the provision of a communication device and a communication method for performing control signaling in the context of EHT WLAN.

[0008] According to an embodiment of the present disclosure, there is provided a communication device including: a circuit that generates a transmission signal including a first signal field having a first portion and a second portion each including the same number of data bits during operation; and a transmitter that transmits the generated transmission signal during operation, wherein the data bits of the second portion of the first signal field do not include version-independent bits.

[0009] According to another embodiment of the present disclosure, there is provided a communication device including: a receiver that receives a transmission signal including a first signal having a first portion and a second portion each including the same number of data bits during operation; and a circuit that processes the received transmission signal during operation, wherein the data bits of the second portion of the first signal field do not include version-independent bits.

[0010] According to yet another embodiment of the present disclosure, there is provided a communication method including: generating a transmission signal including a first signal field having a first portion and a second portion, each including the same number of data bits; and transmitting the generated transmission signal, wherein the second portion of the first signal field does not include version-independent bits.

[0011] Note that a general or specific embodiment can be implemented as a system, a method, an integrated circuit, a computer program, a storage medium, or any optional combination thereof.

[0012] Further benefits and advantages of the disclosed embodiments will become apparent from the specification and the drawings. These benefits and / or advantages can be obtained individually by various embodiments and features of the specification and the drawings, and it is not necessary to provide all these features in order to obtain one or more of such benefits and / or advantages.

Brief Description of the Drawings

[0013] Those of ordinary skill in the art will gain a deep understanding and readily clarify the embodiments of the present disclosure by reading the following description, which is only an example, with reference to the drawings.

Figure 1A

Figure 1B

Figure 1C

Figure 1D

Figure 2A

Figure 2B

Figure 2C

Figure 2D

Figure 3A

Figure 3B

Figure 4A

Figure 4B

Figure 5A

Figure 5B

Figure 5C

Figure 5D

Figure 5E

Figure 5F

Figure 5G

Figure 5H

Figure 5I

Figure 5J

Figure 5K

Figure 6

Figure 7A

Figure 7B

Figure 7C

Figure 7D

Figure 7E

Figure 7F

Figure 7G

Figure 7H

Figure 7I

Figure 8

Figure 9

Figure 10

[0014] Those skilled in the art will understand that the elements in the figures are illustrated in a concise and clear manner and are not necessarily drawn to scale. To assist in the accurate understanding of the embodiments of the present invention, for example, the dimensions of some elements in the illustrations, block diagrams, or flowcharts may be exaggerated compared to other elements.

Embodiments for Carrying Out the Invention

[0015] Some embodiments of the present disclosure will be described by way of example only with reference to the drawings. Similar reference numerals and reference characters in the drawings refer to similar or equivalent elements.

[0016] In the following paragraphs, specific exemplary embodiments will be described with reference to an access point (AP) and a station (STA) that perform uplink or downlink control signaling, particularly in a multiple-input multiple-output (MIMO) wireless network.

[0017] In the context of IEEE 802.11 (Wi-Fi) technology, a station (also referred to synonymously as STA) is a communication device having the ability to use the 802.11 protocol. Based on the definition of IEEE 802.11-2016, a STA can be any device including an IEEE 802.11-compliant media access control (MAC) and physical layer (PHY) interface to the wireless medium (WM).

[0018] A STA can be, for example, a notebook, a desktop personal computer (PC), a personal digital assistant (PDA), an access point, or a Wi-Fi phone within a wireless local area network (WLAN) environment. A STA can be stationary or mobile. In a WLAN environment, the terms "STA", "wireless client", "user", "user device", and "node" are often used synonymously.

[0019] Similarly, an AP (also referred to synonymously as a wireless access point (WAP) in the context of IEEE 802.11 (Wi-Fi) technology) is a communication device that enables a STA within a WLAN to connect to a wired network. An AP is typically connected to a router (via a wired network) as a stand-alone device, but an AP can also be integrated with or used within a router.

[0020] As described above, a STA within a WLAN can function as an AP in other cases, and vice versa. This is because a communication device in the context of IEEE 802.11 (Wi-Fi) technology can include both the hardware elements of a STA and the hardware elements of an AP. In this way, the communication device can switch between the STA mode and the AP mode based on the actual WLAN conditions and / or requirements.

[0021] In a MIMO wireless network, "multiple" means multiple antennas used simultaneously for transmission through a wireless channel and multiple antennas used simultaneously for reception. In this regard, "multiple-input" means multiple transmitter antennas that input wireless signals into the channel, and "multiple-output" means multiple receiver antennas that receive wireless signals from the channel and input them into the receiver. For example, in an N×M MIMO network system, N is the number of transmitter antennas and M is the number of receiver antennas, and N may or may not be equal to M. In the present disclosure, for the sake of simplicity, the number of transmitter antennas and the number of receiver antennas will not be further discussed.

[0022] In a MIMO wireless network, single-user (SU) communication and multi-user (MU) communication can be deployed as communication between communication devices such as APs and STAs. A MIMO wireless network has advantages such as spatial multiplexing and spatial diversity that achieve higher data rates and robustness by using multiple spatial streams. According to various embodiments, the term "spatial stream" can be used interchangeably with the term "spatio-temporal stream" (or STS).

[0023] Figure 1A shows a schematic diagram of SU (single user)-MIMO communication 100 between AP 102 and STA 104 in a MIMO wireless network. As shown, the MIMO wireless network can include one or more STAs (e.g., STA 104, STA 106, etc.). In SU-MIMO communication 100, AP 102 transmits multiple spatio-temporal streams using multiple antennas (e.g., four antennas as shown in Figure 1A) towards a single communication device (i.e., STA 104) for all the spatio-temporal streams. For the sake of brevity, the multiple spatio-temporal streams directed towards STA 104 are shown as a combined data transmission arrow 108 directed towards STA 104.

[0024] SU-MIMO communication 100 can be configured for two-way transmission. As shown in Figure 1A, in SU-MIMO communication 100, STA 104 can transmit multiple spatio-temporal streams using multiple antennas (e.g., two antennas as shown in Figure 1A) towards AP 102 for all the spatio-temporal streams. For the sake of brevity, the multiple spatio-temporal streams directed towards AP 102 are shown as a combined data transmission arrow 110 directed towards AP 102.

[0025] Thus, in the SU-MIMO communication 100 depicted in Figure 1A, both uplink SU transmission and downlink SU transmission in the MIMO wireless network are possible.

[0026] Figure 1B shows a schematic diagram of downlink MU communication 112 between AP 114 and multiple STAs 116, 118, 120 in a MIMO wireless network. The MIMO wireless network can include one or more STAs (e.g., STA 116, STA 118, STA 120, etc.). In downlink MU communication 112, AP 114 uses multiple antennas via spatial mapping or precoding techniques to simultaneously transmit multiple streams to STAs 116, 118, 120 in the network using the same resource unit (RU) and / or different RUs. For example, two spatio-temporal streams can be directed to STA 118, another spatio-temporal stream can be directed to STA 116, and yet another spatio-temporal stream can be directed to STA 120. For the sake of brevity, the two spatio-temporal streams directed to STA 118 are shown as a combined data transmission arrow 124, the spatio-temporal stream directed to STA 116 is shown as a data transmission arrow 122, and the spatio-temporal stream directed to STA 120 is shown as a data transmission arrow 126.

[0027] To enable uplink MU transmission, trigger-based communication is provided in the MIMO wireless network. In this regard, Figure 1C shows a schematic diagram of trigger-based uplink MU communication 128 between AP 130 and multiple STAs 132, 134, 136 in a MIMO wireless network.

[0028] Since multiple STAs 132, 134, 136 participate in trigger-based uplink MU communication, AP 130 needs to coordinate the simultaneous transmission of multiple STAs 132, 134, 136.

[0029] To this end, as shown in FIG. 1C, the AP 130 simultaneously transmits trigger frames 139, 141, 143 to the STAs 132, 134, 136, indicating user-specific resource allocation information (e.g., the number of spatio-temporal streams, the starting STS number, and the RUs allocated) that each STA can use. In response to the trigger frames, the STAs 132, 134, 136 can simultaneously transmit their respective spatio-temporal streams to the AP 130 according to the user-specific resource allocation information indicated in the trigger frames 139, 141, 143. For example, two spatio-temporal streams are directed from the STA 134 to the AP 130, another spatio-temporal stream is directed from the STA 132 to the AP 130, and yet another spatio-temporal stream is directed from the STA 136 to the AP 130. For the sake of brevity, the two spatio-temporal streams directed from the STA 134 to the AP 130 are shown as a combined data transmission arrow 140, the spatio-temporal stream directed from the STA 132 to the AP 130 is shown as a data transmission arrow 138, and the spatio-temporal stream directed from the STA 136 to the AP 130 is shown as a data transmission arrow 142.

[0030] Also, to enable downlink multi-AP communication, trigger-based communication is provided to the MIMO wireless network. In this regard, FIG. 1D shows a schematic diagram of downlink multi-AP communication 144 between the STA 150 and multiple APs 146, 148 in the MIMO wireless network.

[0031] Since multiple APs 146, 148 participate in the trigger-based downlink multi-AP MIMO communication, the master AP 146 needs to coordinate the simultaneous transmission of the multiple APs 146, 148.

[0032] Therefore, as shown in FIG. 1D, the master AP 146 simultaneously transmits trigger frames 147, 153 to the AP 148 and the STA 150, indicating AP-specific resource allocation information (e.g., the number of spatial-temporal streams, the starting STS stream number, the allocated RUs) that each AP can use. In response to the trigger frames, the plurality of APs 146, 148 can transmit their respective spatial-temporal streams to the STA 150 according to the AP-specific resource allocation information indicated in the trigger frame 147. The STA 150 can receive all the spatial-temporal streams according to the AP-specific resource allocation information indicated in the trigger frame 153. For example, two spatial-temporal streams are directed from the AP 146 to the STA 150, and another two spatial-temporal streams are directed from the AP 148 to the STA 150. For the sake of brevity, the two spatial-temporal streams directed from the AP 146 to the STA 150 are shown as a combined data transmission arrow 152, and the two spatial-temporal streams directed from the AP 148 to the STA 150 are shown as a combined data transmission arrow 154.

[0033] In 802.11 WLANs, due to packet / PPDU (Physical Layer Protocol Data Unit)-based transmission and the distributed MAC (Media Access Control) scheme, there is no time scheduling (e.g., the allocation of periodic time slots for data transmission such as TDMA (Time Division Multiple Access)). The scheduling of frequency and spatial resources is performed on a packet-by-packet basis. In other words, the resource allocation information is PPDU-based.

[0034] FIG. 2A shows an example of the format of a PPDU 156 used for single-user communication between an AP and an STA in a HE WLAN. Such a PPDU 156 is referred to as a HE SU PPDU 156. The HE SU PPDU 156 can include a non-High Throughput Short Training (L-STF) field, a non-High Throughput Long Training (L-LTF) field, a non-High Throughput SIGNAL (L-SIG) field, a Repeated L-SIG (RL-SIG) field, a HE SIGNAL A (HE-SIG-A) field 158, a HE Short Training (HE-STF) field, a HE Long Training (HE-LTF) field, a Data field 170, and a Packet Extension (PE) field. The RL-SIG field is mainly used to identify the format of the HE PPDU. The HE-SIG-A field 158 includes control information necessary for decoding the Data field, such as uplink / downlink, modulation and coding scheme (MCS), bandwidth (BW), etc.

[0035] Figure 2B shows an example of the format of a PPDU 160 used for downlink MU communication between an AP and multiple STAs in HE WLAN, such as OFDMA (Orthogonal Frequency Division Multiple Access) transmission including MU-MIMO transmission with a single RU (Resource Unit) or full-band MU-MIMO transmission. Such a PPDU 160 is referred to as a HE MU PPDU 160. The HE MU PPDU has a format similar to that of the HE SU PPDU, but can include a HE Signal B (HE-SIG-B) field 166. In particular, the HE MU PPDU 160 can include an L-STF field, an L-LTF field, an L-SIG field, an RL-SIG field, a HE-SIG-A field 162, a HE-SIG-B field 166, a HE-STF field, a HE-LTF field, a Data field 170, and a PE field. In the HE MU PPDU 160, the HE-SIG-B field 166 provides OFDMA and MU-MIMO resource allocation information so that, as indicated by arrow 168, the STA can identify the corresponding resources used in the Data field 170. The HE-SIG-A field 162 includes information necessary to decode the HE-SIG-B field 166 (e.g., the MCS of HE-SIG-B, the number of HE-SIG-B symbols), as indicated by arrow 164.

[0036] Figure 2C shows the HE-SIG-B field 166 in more detail. The HE-SIG-B field 166 includes (or consists of) a Common field 172 (when present) followed by a User Specific field 174, which together are referred to as the HE-SIG-B content channel. The HE-SIG-B field 166 includes an RU Allocation subfield that indicates the RU information for each allocation. The RU information includes the position of the RU in the frequency domain, indication information of the RU allocated for non-MU-MIMO or MU-MIMO allocation, and the number of users in the MU-MIMO allocation. The Common field 172 does not exist in the case of full-band MU-MIMO transmission. In this case, the RU information (e.g., the number of users in the MU-MIMO allocation) is signaled in the HE-SIG-A field 162.

[0037] The User Specific field 174 includes (or consists of) one or more User fields for non-MU-MIMO allocation and / or MU-MIMO allocation. The User field includes user information (i.e., user-specific allocation information) indicating a user-specific allocation. In the example shown in Figure 2C, the User Specific field 174 includes five User fields (User field 0,..., User field 4), and the user-specific allocation information regarding the allocation (allocation 0) is provided by User field 0, and the user-specific allocation information regarding a further allocation (allocation 1 including three MU-MIMO users) is provided by User field 1, User field 2, and User field 3, and the user-specific allocation information regarding a further allocation (allocation 2) is provided by User field 4.

[0038] FIG. 2D shows the format of the PPDU 180 used for uplink MU communication between an AP and multiple STAs in a HE WLAN. Such a PPDU 180 is referred to as a HE TB (trigger-based) PPDU 180. The HE TB PPDU can have a format similar to that of a HE SU PPDU. Specifically, the HE TB PPDU 180 can include an L-STF field, an L-LTF field, an L-SIG field, an RL-SIG field, a HE-SIG-A field 182, a HE-STF field, a HE-LTF field, a Data field, and a PE field. The HE-STF of the HE TB PPDU 180 has a duration of 8 μs. The HE TB PPDU 180 is used for uplink MU transmission in response to a trigger frame. Instead of using the HE-SIG-B field, the information required for uplink MU transmission from one or more STAs is conveyed by the trigger frame that requests this transmission. In a general transmission of the HE TB PPDU 180, the HE-SIG-A related information is copied from the requesting trigger frame to the HE-SIG-A field 182 of the HE TB PPDU 180.

[0039] In an 11ax HE WLAN, only preamble puncturing of PPDUs transmitted to multiple STAs is permitted. Due to the increase in the maximum channel bandwidth from 160 MHz to 320 MHz and the increase in the maximum number of spatial streams from 8 to 16, the object of the present disclosure is to substantially overcome the existing problem of providing a communication device and a communication method that perform control signaling to enable preamble puncturing of PPDUs transmitted to a single STA in order to improve the spectral efficiency of an EHT WLAN compared to an 11ax HE WLAN.

[0040] According to various embodiments, the EHT WLAN supports non-trigger-based communication as shown in FIGS. 1A and 1B and trigger-based communication as shown in FIGS. 1C and 1D. In non-trigger-based communication, a communication device transmits a PPDU to one or more other communication devices without an explicit request. In trigger-based communication, a communication device transmits a PPDU to one or more other communication devices only after receiving a requested trigger frame.

[0041] FIG. 3A shows a partially framed schematic view of a communication device 300 according to various embodiments. The communication device 300 can be implemented as an AP or STA according to various embodiments.

[0042] As shown in FIG. 3A, communication device 300 can include circuit 314, at least one wireless transmitter 302, at least one wireless receiver 304, and at least one antenna 312 (only one antenna is depicted in FIG. 3A for the purpose of illustration for simplicity). Circuit 314 can include at least one controller 306 for use in executing tasks designed to be executed by at least one controller 306, including control of communication with one or more other communication devices in a MIMO wireless network, with the assistance of software and hardware. Circuit 314 can further include at least one transmission signal generator 308 and at least one reception signal processor 310. At least one controller 306 can control at least one transmission signal generator 308 to generate a PPDU (e.g., a PPDU used for non-trigger-based communication if communication device 300 is an AP, or a PPDU used for trigger-based multi-AP joint transmission, and e.g., a PPDU used for non-trigger-based communication if communication device 300 is a STA, or a PPDU used for trigger-based uplink transmission) to be transmitted to one or more other communication devices via at least one wireless transmitter 302, and can control at least one reception signal processor 310 to process a PPDU (e.g., a PPDU used for non-trigger-based communication if communication device 300 is an AP, or a PPDU used for trigger-based uplink transmission, and e.g., a PPDU used for non-trigger-based communication if communication device 300 is a STA, or a PPDU used for trigger-based multi-AP joint transmission) received from one or more other communication devices through at least one wireless receiver 304 under the control of at least one controller 306. At least one transmission signal generator 308 and at least one reception signal processor 310 can be stand-alone modules of communication device 300 that communicate with at least one controller 306 for the functions described above, as shown in FIG. 3A.Alternatively, at least one transmission signal generator 308 and at least one reception signal processor 310 may be included in at least one controller 306. Those skilled in the art will understand that the arrangement of these functional modules is flexible and can vary according to actual needs and / or requirements. The data processing device, storage device, and other related control devices can be provided on a suitable circuit board and / or chipset. In various embodiments, during operation, at least one wireless transmitter 302, at least one wireless receiver 304, and at least one antenna 312 can be controlled by at least one controller 306.

[0043] The communication device 300 provides the functions necessary for control signaling in non-trigger-based communication and trigger-based communication during operation. For example, the communication device 300 may be an AP, and the circuit 314 (e.g., at least one transmission signal generator 308 of the circuit 314) can generate a transmission signal (e.g., a PPDU used for non-trigger-based communication or a PPDU used for trigger-based multi-AP joint transmission) during operation. The transmission signal includes a first signal field having a first part and a second part, each containing the same number of data bits, and the data bits of the second part of the first signal field do not include version-independent bits. The wireless transmitter 302 can transmit the generated transmission signal to one or more other communication devices during operation.

[0044] The communication device 300 may be a STA, and the wireless receiver 304 can receive, during operation, a transmission signal (e.g., a PPDU used for non-trigger-based communication or a PPDU used for trigger-based multi-AP joint transmission) from another communication device (e.g., an AP). The transmission signal includes a first signal field having a first portion and a second portion, each containing the same number of data bits, and the data bits of the second portion of the first signal field do not include version-independent bits. The circuit 314 (e.g., at least one received signal processor 310 of the circuit 314) can process the received transmission signal during operation.

[0045] FIG. 3B shows a flowchart 316 illustrating a communication method for transmitting control signaling according to various embodiments. In step 318, a transmission signal is generated, and the transmission includes a first signal field having a first portion and a second portion, each containing the same number of data bits, and the data bits of the second portion of the first signal field do not include version-independent bits. In step 320, the generated transmission signal is transmitted to one or more other communication devices.

[0046] In one embodiment, the first signal field of the transmission signal has a single format in non-trigger-based communication with one or more other communication devices (such as STAs). In another embodiment, the transmission signal includes a second signal field having a part of version-dependent bits in non-trigger-based communication. In such an embodiment, the second signal field has a format when the transmission signal is transmitted to one other communication device and another format when the transmission signal is transmitted to a plurality of other communication devices. In one embodiment, when the transmission signal is transmitted to one other communication device, the second signal field can include a preamble puncturing bitmap. In yet another embodiment, the first signal field includes information for interpreting the second signal field. This enables preamble puncturing of the PPDU transmitted to one communication device, enables efficient signaling support for EHT WLAN superior to 11ax HE WLAN, and improves spectral efficiency, which is advantageous.

[0047] In the following paragraphs, specific exemplary embodiments will be described with reference to an AP and a plurality of STAs that perform control signaling enabling preamble puncturing of a PPDU transmitted to a single communication device in non-trigger-based communication.

[0048] FIG. 4A shows a flowchart 400 illustrating downlink communication according to an embodiment, where the downlink communication is communication between an AP 402 and a single communication device 404, or between the AP 402 and multiple communication devices (such as STA 404, STA 406, etc.). Contention-based channel access procedures, such as enhanced distributed channel access (EDCA) procedures, are shown by block 408, and a short interframe spacing (SIFS) 411 is shown. The AP 402 can generate a transmission signal (e.g., an EHT basic PPDU) 410 that includes a first signal field having a first portion and a second portion, each including the same number of data bits, and the data bits of the second portion of the first signal field do not include version-independent bits. The first signal field of the transmission signal 410 can have a single format regardless of whether the transmission signal 410 is transmitted to the STA 404 or the STAs 404, 406. In one embodiment, the transmission signal 410 can include a second signal field that includes a portion of the version-dependent bits. When communicating with multiple or two or more communication devices such as the STAs 404, 406, the second signal field of the transmission signal 410 can have a different format from the format of the transmission signal 410 transmitted to a single communication device such as the STA 404. In one embodiment, when the transmission signal 410 is transmitted to the STA 404, the second signal field can include a preamble puncturing bitmap. In yet another embodiment, the first signal field includes information for interpreting the second signal field. The wireless transmitter of the AP 402 can transmit the generated transmission signal 410 to the STA 404 or the STAs 404, 406.

[0049] In an IEEE 802.11 network, SIFS is the time interval before a confirmation response is transmitted by a STA. After the last symbol of the transmission signal 410 is transmitted, SIFS 411 becomes valid. In 412, when the transmission signal 410 is transmitted to STAs 404, 406, the wireless transmitters of STAs 404, 406 can simultaneously transmit their respective block acknowledgment (BA) frames 414, 415, or when the transmission signal 410 is transmitted to STA 404, the wireless transmitter of STA 404 can transmit BA frame 414.

[0050] According to the present disclosure, the EHT basic PPDU can be used for non-trigger-based SU communication or MU communication. FIG. 5A shows an example of the format of the EHT basic PPDU 500. The EHT basic PPDU 500 includes an L-STF field, an L-LTF field, an L-SIG field, an RL-SIG field, a Universal Signal (U-SIG) field 502, an EHT Signal (EHT-SIG) field 504, an EHT-STF field, an EHT-LTF field, a Data field, and a PE field. The L-STF field, the L-LTF field, the L-SIG field, the RL-SIG field, the U-SIG field, and the EHT-SIG field can be grouped as pre-EHT modulated fields, and the EHT-STF field, the EHT-LTF field, the Data field, and the PE field can be grouped as EHT modulated fields. Both the U-SIG field 502 and the EHT-SIG field 504 are present in the EHT basic PPDU transmitted to a single STA or multiple STAs.

[0051] According to various embodiments, the U-SIG field 502 has a duration of two OFDM (Orthogonal Frequency Division Multiplexing) symbols. The data bits of the U-SIG field 502 are encoded and modulated together, similar to the HE-SIG-A field of 802.11ax. The modulated data bits of the U-SIG field 502 are mapped to 52 data tones of each of the two OFDM symbols and replicated for each 20 MHz frequency segment, similar to the HE-SIG-A field of 802.11ax. An example of transmitting the U-SIG field 502 when the bandwidth of the EHT basic PPDU 500 is 80 MHz is shown in FIG. 5B.

[0052] In various embodiments, the U-SIG field 502 has the same format regardless of whether the EHT basic PPDU 500 is transmitted to a single STA or multiple STAs. The U-SIG field 502 comprises two parts, namely U-SIG1 and U-SIG2, each containing 26 data bits. The U-SIG field 502 includes all version-independent bits and some version-dependent bits. All version-independent bits are included in U-SIG1, which has static positions and bit definitions across different physical layer (PHY) versions. The version-independent bits include a PHY version identifier (3 bits), an uplink / downlink (UL / DR) flag (1 bit), a basic service set (BSS) color (e.g., 6 bits), and a transmit opportunity (TXOP) duration (e.g., 7 bits). The PHY version identifier of the version-independent bits is used to identify the exact PHY version starting from 802.11be. By including all version-independent bits in one part (i.e., U-SIG1) of the U-SIG field 502, legacy STAs only need to parse U-SIG1, thus improving their power efficiency. On the other hand, the version-dependent bits may have variable bit definitions for each PHY version. The part of the version-dependent bits included in the U-SIG field 502 can include PPDU format, SU / MU flag, bandwidth, EHT-SIG related bits used to interpret the EHT-SIG field 504, and spatial reuse related bits used for coexistence with unintended STAs.

[0053] An example of the format of the U-SIG field 502 is shown in Table 1. As described above, the U-SIG field 502 includes two parts, namely U-SIG1 and U-SIG2, and each of the two parts includes 26 data bits. U-SIG1 includes a PHY Version Identifier field, a UL / DL Flag field, a BSS Color field, a TXOP Duration field, a PPDU Format field, a SU / MU Flag field, and a BW field. U-SIG2 includes an EHT-SIG Compression field, an EHT-SIG EHT MCS field, an EHT-SIG Dual sub-Carrier Modulation (DCM) field, a Number Of EHT-SIG Symbols Or MU-MIMO Users field, a Spatial Reuse field, followed by padding bits, a Cyclic Redundancy Check (CRC) field for error detection, and tail bits. Unless otherwise specified in this specification, it will be apparent to those of ordinary skill in the art that the standard definitions, protocols, and functions of most of the fields of the U-SIG field 502 described in Table 1 are obtained from the 802.11ax specification.

[0054] According to the present disclosure, when the PHY Version Identifier field indicates 802.11be, the PPDU Format field is set to "0" for an EHT basic PPDU and "1" for an EHT TB PPDU. When the PPDU Format field is set to "0" indicating an EHT basic PPDU, the SU / MU Flag field is set to "0" for an EHT basic PPDU transmitted to a single STA and "1" for an EHT basic PPDU transmitted to multiple STAs. The preamble puncturing mode is only permitted when the bandwidth of the PPDU is 80 MHz or more. Therefore, the BW field is set to "0" for 20 MHz, "1" for 40 MHz, "2" for 80 MHz non-preamble puncturing mode, "3" for 160 MHz and 80+80 MHz non-preamble puncturing mode, "4" for 320 MHz and 160+160 MHz non-preamble puncturing mode, "5" for 80 MHz preamble puncturing mode, "6" for 160 MHz and 80+80 MHz preamble puncturing mode, and "7" for 320 MHz and 160+160 MHz preamble puncturing mode.

Table 1

[0055] Returning to FIG. 5A, the EHT-SIG field 504 of the EHT basic PPDU 500 can include the remaining version-dependent bits. The EHT-SIG field 504 has a variable MCS and variable length. The EHT-SIG field 504 has a user-specific field following the common field, and these are collectively referred to as the EHT-SIG content channel. Different from the U-SIG field 502, the format of the EHT-SIG field 504 depends on whether the EHT basic PPDU 500 is transmitted to a single STA or multiple STAs. Below, the differences in the EHT-SIG format when transmitted to a single STA and when transmitted to multiple STAs will be described.

[0056] When an EHT basic PPDU is transmitted to a single STA, the Common field of the EHT-SIG field 504 contains a single Common field 1, and the User Specific field contains a single User field. Further, regardless of the BW of the EHT basic PPDU, the EHT-SIG content channel is one and is replicated for each 20 MHz frequency segment. The Common field and the User Specific field can be encoded separately or together, resulting in two different EHT-SIG field format options. FIG. 5C shows an example of the format of the EHT-SIG field 504 when the Common field 506 and the User Specific field 508 are encoded separately when the EHT basic PPDU is transmitted to a single STA (Option 1). The Common field 506 contains a single Common field 1 506a, and the User Specific field 508 contains a single User field 508a. The Common field 506 and the User Specific field 508 are encoded separately. As a result, as shown in FIG. 5C, a CRC field and tail bits are added to each of the Common field 1 506a of the Common field 506 and the User field 508a of the User Specific field 508.

[0057] Figure 5D shows another format example of the EHT-SIG field 504 when the EHT basic PPDU is transmitted to a single STA (Option 2). In this embodiment, the EHT-SIG field 504 includes a single common field 1 506a of the common field 506, followed by a single user field 508a of the user specific field 508, and a CRC field and tail bits added to the field 508a. In such a format of the EHT-SIG field encoded together, the number of CRC fields and tail bits used in the EHT-SIG field is reduced, and thus the signaling overhead is reduced, which is advantageous.

[0058] Examples of the formats of the Common Field 1 506a and the User Field 508a when the EHT basic PPDU 500 is transmitted to a single STA are shown in Table 13 and Table 2, respectively. The Common Field 1 506a can include a Low Density Parity Check (LDPC) Extra Symbol Segment subfield, a Pre-FEC Padding Factor subfield, a PE Disambiguity subfield, a Space-Time Block Coding (STBC) subfield, a Doppler subfield, a GI-LTF Size subfield, an EHT-LTF Mode subfield, a Beam Change subfield, and a Preamble Puncturing Bitmap subfield. The User Field 508a can have a field size of 22 bits and can include a STA Identifier (ID) field, an EHT MCS field, a DCM field, a Number Of Space-Time Streams (NSTS) And Midamble Periodicity field, a Coding field, and a Beamformed field. The STA ID is included in the User Field so that an unintended STA can discard the remaining EHT basic PPDU 500 to improve power efficiency.Unless otherwise specified in this specification, it will be apparent to those of ordinary skill in the art that the standard definitions, protocols, and functions of most fields of the Common Field 1 506a and User Field 508a described in Table 13 and Table 2 are obtained from the 802.11ax specification.

Table 2

[0059] According to the present disclosure, when the EHT basic PPDU 500 is transmitted to a single STA and the BW field of the U-SIG field 502 is set to "4", "5", "6", "7" respectively indicating the preamble puncturing mode of 80 MHz, 160 (or 80 + 80) MHz, or 320 (or 160 + 160) MHz, the preamble puncturing bitmap field exists in the common field 506 of the EHT-SIG field 504. The preamble puncturing bitmap field has a variable bit width depending on the bandwidth of the EHT basic PPDU 500.

[0060] The Preamble Puncturing Bitmap field can have two options. In Option 1, when the BW field indicates a preamble puncturing mode of 80 MHz, 160 (or 80 + 80) MHz, or 320 (or 160 + 160) MHz, the Preamble Puncturing Bitmap field has 3 bits, 7 bits, or 15 bits respectively. Each bit indicates whether a 20 MHz frequency segment other than the primary 20 MHz is being punctured. In Option 2, when the BW field indicates a preamble puncturing mode of 80 MHz, 160 (or 80 + 80) MHz, or 320 (or 160 + 160) MHz, the Preamble Puncturing Bitmap field has 3 bits, 7 bits, or 7 bits respectively. Specifically, when the BW field indicates an 80 MHz or 160 (or 80 + 80) MHz preamble puncturing mode, each bit indicates whether a 20 MHz frequency segment other than the primary 20 MHz is being punctured, and when the BW field indicates a 320 MHz or 160 + 160 MHz preamble puncturing mode, each bit indicates whether a 40 MHz frequency segment other than the primary 40 MHz is being punctured. In the 320 MHz or 160 + 160 MHz preamble puncturing mode, the effect of indicating a 40 MHz frequency segment instead of 20 MHz is a trade-off between signaling overhead and spectral efficiency. With the above features, preamble puncturing of the PPDU transmitted to a single STA using the EHT basic PPDU 500 becomes possible, which is advantageous.

[0061] Furthermore, the EHT-LTF mode field of the common field 1 506a is set to "0" indicating that sub-carrier interleaved EHT-LTF symbols are not used, and "1" indicating that sub-carrier interleaved EHT-LTF symbols may be used. Examples of sub-carrier interleaved EHT-LTF symbols are described in Non-Patent Document 1. Such sub-carrier interleaved EHT-LTF symbols can be used to maintain the number of EHT-LTF symbols, especially when the number of spatio-temporal streams is 9 or more.

[0062] According to various embodiments, the format of the EHT-SIG field when the EHT basic PPDU 500 is transmitted to a plurality of STAs is different from the format of the EHT-SIG field when transmitted to a single STA. In the case of the EHT basic PPDU 500 transmitted to a plurality of STAs, the common field of the EHT-SIG field 504 includes two elements, namely common field 1 and common field 2, and the user specific field includes one or more user fields, which are collectively referred to as the EHT-SIG content channel. Furthermore, depending on the bandwidth of the EHT basic PPDU, there is one or two EHT-SIG content channels. Specifically, the EHT-SIG field 504 including the common field 510 and the user specific field 512 is separately encoded for each frequency segment of L×20 MHz, where L = 1 or 2.

[0063] Figure 5E is a table showing how the number of EHT-SIG content channels depends on the bandwidth and the value of L in various embodiments. As shown in Figure 5E, when the bandwidth is 20 MHz, L can only be 1 because the EHT-SIG field is encoded every 20 MHz and there is only one EHT-SIG content channel. In an embodiment where the bandwidth is 40 MHz, the AP can assign 1 or 2 as the value of L. When L is set to "1", there are two EHT-SIG content channels. When L is set to "2", there is only one EHT-SIG content channel. In embodiments where the bandwidth is 80 MHz, 80 + 80 MHz, 160 MHz, 160 + 160 MHz, or 320 MHz, there are two EHT-SIG content channels regardless of the value of L. Details will be described below.

[0064] Figure 5F shows a diagram of the mapping of one or two EHT-SIG content channels in a 40 MHz EHT basic PPDU. The number of EHT-SIG content channels depends on the bandwidth and the value of L as shown in Figure 5E. A 40 MHz channel includes two 20 MHz frequency segments. When L = 1, there are two EHT-SIG content channels (i.e., EHT-SIG content channel 1 and EHT-SIG content channel 2), which are transmitted in the first and second 20 MHz frequency segments respectively. When L = 2, there is only one EHT-SIG content channel.

[0065] Figure 5G shows a diagram of the mapping of two EHT-SIG content channels (i.e., EHT-SIG content channel 1 and EHT-SIG content channel 2) in an 80 MHz EHT basic PPDU. When L = 1, in an 80 MHz channel containing four 20 MHz frequency segments, EHT-SIG content channel 1 is replicated and transmitted in the first and third 20 MHz frequency segments, and EHT-SIG content channel 2 is replicated and transmitted in the second and fourth 20 MHz frequency segments. When L = 2, in an 80 MHz channel containing two 40 MHz frequency segments, EHT-SIG content channel 1 is transmitted in the first 40 MHz frequency segment, and EHT-SIG content channel 2 is transmitted in the second 40 MHz frequency segment.

[0066] Figure 5H shows the mapping of two EHT-SIG content channels in an 80 + 80 MHz or 160 MHz EHT basic PPDU. When L = 1, in an 80 + 80 MHz or 160 MHz channel containing eight 20 MHz frequency segments, EHT-SIG content channel 1 is replicated and transmitted in the first, third, fifth, and seventh 20 MHz frequency segments, and EHT-SIG content channel 2 is replicated and transmitted in the second, fourth, sixth, and eighth 20 MHz frequency segments. When L = 2, in an 80 + 80 MHz or 160 MHz channel containing four 40 MHz frequency segments, EHT-SIG content channel 1 is replicated and transmitted in the first and third 40 MHz frequency segments, and EHT-SIG content channel 2 is replicated and transmitted in the second and fourth 40 MHz frequency segments.

[0067] Figure 5I shows a mapping of two EHT-SIG content channels in a 160 + 160 MHz or 320 MHz EHT basic PPDU. When L = 1, in a 160 + 160 MHz or 320 MHz channel containing 16 20 MHz frequency segments, EHT-SIG content channel 1 is first replicated and transmitted in the 1st, 3rd, 5th, 7th, 9th, 11th, 13th, and 15th 20 MHz frequency segments, and EHT-SIG content channel 2 is replicated and transmitted in the 2nd, 4th, 6th, 8th, 10th, 12th, 14th, and 16th 20 MHz frequency segments. When L = 2, in a 160 + 160 MHz or 320 MHz channel containing 8 40 MHz frequency segments, EHT-SIG content channel 1 is replicated and transmitted in the 1st, 3rd, 5th, and 7th 40 MHz frequency segments, and EHT-SIG content channel 2 is replicated and transmitted in the 2nd, 4th, 6th, and 8th 40 MHz frequency segments.

[0068] In various embodiments, for an EHT PPDU transmitted to multiple STAs, the User Specific field can be composed of one or more User Block fields, and each User Block field includes one or two User fields. For example, as shown in FIGS. 5J and 5K, the User Specific field 512 includes three User Block fields 1, 2, and 3. User Block field 1 includes two User fields such as User field 1 and User field 2. User Block field 2 includes two User fields such as User field 3 and User field 4. User Block field 3 includes one User field 5. One or two User fields in each of the User Block fields 1, 2, and 3 have a CRC field for error detection and tail bits added thereto. In one embodiment, the last User Block can be composed of one or two User fields depending on the total number of User fields permitted in the User Specific field 512, which indicates odd or even.

[0069] However, the common fields including common field 1 and common field 2 can be encoded together (option 1) or separately (option 2), resulting in two options for the EHT-SIG field format. FIG. 5J shows an example of the format of the EHT-SIG field 504 when common field 1 and common field 2 are encoded together (option 1) in an EHT basic PPDU transmitted to multiple STAs. In this embodiment, in common field 510, common field 2 510b follows common field 1 510a, and a block of CRC field and tail bits is added to this field 510b. As an advantage of the format of such an EHT-SIG field having common fields encoded together, the number of CRC fields and tail bits used in the EHT-SIG field can be reduced, thus reducing the signaling overhead.

[0070] FIG. 5K shows an example of the format of the EHT-SIG field 504 when the common field 510 is encoded separately (option 2) in an EHT basic PPDU transmitted to multiple STAs. In this embodiment, a CRC field and tail bits can be included at the end of each separately encoded field (i.e., common field 1 510a and common field 2 510b).

[0071] However, in one embodiment, when the EHT-SIG Compression field of the U-SIG field 502 is set to "1" indicating full-band MU-MIMO transmission, common field 2 may not be present. In this case, both option 1 and option 2 of the format of the EHT basic PPDU transmitted to multiple STAs are the same.

Table 3

[0072] Examples of the formats of Common Field 1 510a and Common Field 2 510b when the EHT basic PPDU 500 is transmitted to multiple STAs are shown in Table 3 and Table 14, respectively. Common Field 1 510a can include an LDPC Extra Symbol Segment subfield, a Pre-FEC Padding Factor subfield, a PE Disambiguity subfield, a Doppler subfield, a GI-LTF Size subfield, an EHT-LTF Mode subfield, and a Number Of EHT-LTF Symbols And Midamble Periodicity subfield. Common Field 1 has a field size of 12 bits and is the same across all EHT-SIG content channels. Common Field 2 510b can include an RU Allocation field and a Center 26-Tone RU field. The RU Allocation subfield for an EHT-SIG content channel corresponding to one or more 20 MHz frequency segments indicates the RU allocation including the size of the RUs and their placement within the frequency region, and can also indicate the preamble puncturing pattern. The RU Allocation subfield and the Center 26-Tone RU subfield have different field sizes depending on the BW of the EHT basic PPDU. Also, Common Field 2 may vary depending on the RU allocation among EHT-SIG content channels. Note that when the EHT-SIG Compression subfield of the U-SIG field 502 is set to "1", Common Field 2 does not exist.

[0073] Examples of the formats of the User field in the case of non-MU MIMO allocation and MU MIMO allocation are shown in Table 4 and Table 5, respectively. In the case of non-MU MIMO allocation, the User field can include an STA ID field, an EHT MCS field, a DCM field, an NSTS field, a Coding field, and a Beamformed field, while in the case of MU MIMO allocation, the User field can include an STA ID field, an EHT MCS field, a Spatial Configuration field, and a Coding field. It should be noted that the standard definitions, protocols, and functions of all fields of the Common Field 1, Common Field 2, and User field described in Tables 3 to 5 and Table 14 can be obtained from the 802.11ax specification, unless otherwise specified in this specification, which will be obvious to those of ordinary skill in the art.

Table 4

Table 5

[0074] Table 15 summarizes the formats of different EHT-SIG fields in an EHT basic PPDU according to the method by which the EHT-SIG field is encoded, according to various embodiments provided in the present disclosure. When the EHT basic PPDU is transmitted to a single STA, i.e., when the SU / MU flag field of the U-SIG field is set to "0", the common field of the EHT-SIG field includes a single common field 1, and the user specific field includes a single user field. The common field and the user specific field can be encoded separately (i.e., option 1) or together (i.e., option 2). On the other hand, when the EHT basic PPDU is transmitted to multiple STAs, i.e., when the SU / MU flag field of the U-SIG field is set to "1", the common field and the user specific field are encoded separately. The common field includes the common field 1, and when the EHT compression field of the U-SIG field is set to "0", it further includes the common field 2. The common field 1 and the common field 2 can be encoded together (i.e., option 1) or separately (i.e., option 2).

[0075] FIG. 6 shows an example of the format of an EHT TB PPDU 600. The EHT TB PPDU 600 has a structure similar to that of the EHT basic PPDU 500, but does not have an EHT-SIG field 504. The EHT TB PPDU 600 can include an L-STF field, an L-LTF field, an L-SIG field, a FIF field, a U-SIG field 602, an EHT-STF field, an EHT-LTF field, a Data field, and a PE field. The L-STF field, the L-LTF field, the L-SIG field, the RL-SIG field, and the U-SIG field 602 can be grouped as pre-EHT modulation fields, and the EHT-STF field, the EHT-LTF field, the Data field, and the PE field can be grouped as EHT modulation fields. The EHT TB PPDU can be used for trigger-based communication in response to a requested trigger frame. For example, the EHT TB PPDU can be used by STAs 404, 406 to transmit BA frames 414, 415 when an EHT basic PPDU 410 is transmitted to the STAs 404, 406 and includes one or more trigger frames, as shown in FIG. 4A.

[0076] Table 6 shows an example of the format of the U-SIG field 602 of the EHT TB PPDU 600. Similar to the EHT basic PPDU 500, the U-SIG field 602 includes two parts, namely U-SIG1 and U-SIG2, with each part containing 26 data bits. In this embodiment, all bits that are independent of the version can be included in U-SIG1. The first part of the U-SIG field 602 (i.e., U-SIG1) includes a PHY Version Identifier field, a UL / DL Flag field, a BSS Color field, a TXOP Duration field, a PPDU Format field, and a BW field. The PHY Version Identifier field is used to identify the exact PHY version starting from 802.11be. The second part of the U-SIG field 602 (i.e., U-SIG2) includes Spatial Reuse 1 to 4 fields, followed by a CRC field and tail bits. Information of some fields of the U-SIG field 602 (such as the BW field and Spatial Reuse 1 to 4 fields) can be copied from the corresponding trigger frame that requests the transmission of the EHT TB PPDU 600. It should be clear to those of ordinary skill in the art that most of the standard definitions, protocols, and functions of the fields of the U-SIG field 602 of the EHT TB PPDU 600 are obtained from the 802.11ax specification.

Table 6

[0077] FIG. 4B shows a flowchart 420 illustrating downlink communication according to another embodiment, where the downlink communication is communication between an AP 422 and a single communication device 424, or between the AP 422 and multiple communication devices such as STAs 424, 426. A contention-based channel access procedure, such as an EDCA procedure, is shown by block 428, and SIFS 431 is shown. The AP 422 can generate a transmission signal (e.g., an EHT SU PPDU or an EHT MU PPDU) 430 that includes a first signal field having a first portion, a second portion, and a third portion, each of which contains the same number of data bits, and the data bits of the second and third portions of the first signal field do not include version-independent bits. The first portion of the first signal field of the transmission signal 430 can have a single format regardless of whether the transmission signal 430 is transmitted to the STA 424 or the STAs 424, 426. The second or third portion of the first signal field of the transmission signal 430 can have different formats depending on whether the transmission signal 430 is transmitted to either the STA 424 or the STAs 424, 426. In one embodiment, the transmission signal 430 can include a second signal field when the transmission signal 430 is transmitted to the STAs 424, 426. In this case, the first signal field includes information for interpreting the second signal field. In one embodiment, the first signal field can include a preamble puncturing bitmap when the transmission signal 430 is transmitted to the STA 424. The wireless transmitter of the AP 422 can transmit the generated transmission signal 430 to the STA 424 or the STAs 424, 426.

[0078] After the last symbol of the transmission signal 430 is transmitted, SIFS 431 becomes valid. At 432, the wireless transmitters of STAs 424 and 426 can simultaneously transmit their respective BA frames 434 and 435 when the transmission signal 430 is transmitted to STAs 424 and 426, or the wireless transmitter of STA 424 can transmit its own BA frame 434 when the transmission signal 430 is transmitted to STA 424.

[0079] According to the present disclosure, EHT SU PPDU and EHT MU PPDU can be used for non-trigger-based communication. In particular, EHT SU PPDU is used when transmitting to a single STA, and EHT MU PPDU is used when transmitting to multiple STAs.

[0080] Figures 7A and 7B show examples of the respective formats of EHT SU PPDU 700 and EHT MU PPDU 704. EHT MU PPDU 704 has a format similar to EHT basic PPDU 500 and includes an L-STF field, an L-LTF field, an L-SIG field, an RL-SIG field, a U-SIG field 702, an EHT-SIG field 708, an EHT-STF field, an EHT-LTF field, a Data field, and a PE field. Note that the L-STF field, the L-LTF field, the L-SIG field, the RL-SIG field, the U-SIG field 702, and the EHT-SIG field 708 can be grouped as pre-EHT modulation fields, and the EHT-STF field, the EHT-LTF field, the Data field, and the PE field can be grouped as EHT modulation fields. On the other hand, EHT SU PPDU 700 can include a format similar to EHT basic PPDU 500 but does not have an EHT-SIG field. This can reduce the signaling overhead of EHT SU PPDU, which is advantageous.

[0081] The U-SIG field 702 includes all version-independent bits, and in the case of an EHT SU PPDU, all version-dependent bits, and in the case of an EHT MU PPDU, some of the version-dependent bits. According to various embodiments, the U-SIG field 702 has a duration of two OFDM symbols. The data bits of the U-SIG field 702 are encoded and modulated together, similar to the HE-SIG-A field of 802.11ax. The modulated data bits of the U-SIG field 702 are mapped to 52 data tones of each of the two OFDM symbols, similar to the HE-SIG-A field of 802.11ax.

[0082] In the present disclosure, the U-SIG field 702 includes one or two content channels according to the BW of the EHT SU PPDU 700 or the EHT MU PPDU 704. Specifically, the U-SIG field 702 of a 20MHz EHT SU PPDU or EHT MU PPDU includes one U-SIG content channel, and the U-SIG field 702 of an EHT SU PPDU or EHT MU PPDU having a BW of 40MHz or more includes two U-SIG content channels.

[0083] FIG. 7C shows a diagram of the mapping of two U-SIG content channels in a 40 MHz EHT SU PPDU or EHT MU PPDU. A 40 MHz channel includes two 20 MHz frequency segments. The two U-SIG content channels (i.e., U-SIG content channel 1 and U-SIG content channel 2) are transmitted in the first and second 20 MHz frequency segments, respectively. FIG. 7D shows a diagram of the mapping of two U-SIG-B content channels in an 80 MHz EHT SU PPDU or EHT MU PPDU. An 80 MHz channel includes four 20 MHz frequency segments. U-SIG content channel 1 is replicated and transmitted in the first and third 20 MHz frequency segments, and U-SIG content channel 2 is replicated and transmitted in the second and fourth 20 MHz frequency segments.

[0084] Figure 7E shows a diagram of the mapping of two U-SIG content channels in an 80+80 MHz or 160 MHz EHT MU PPDU. The 80+80 MHz or 160 MHz channel contains eight 20 MHz frequency segments. U-SIG content channel 1 is replicated and transmitted in the first, third, fifth, and seventh 20 MHz frequency segments, and U-SIG content channel 2 is replicated and transmitted in the second, fourth, sixth, and eighth 20 MHz frequency segments. Figure 7F shows a diagram of the mapping of two U-SIG content channels in a 160+160 MHz or 320 MHz EHT MU PPDU. The 160+160 MHz or 320 MHz channel contains sixteen 20 MHz frequency segments. U-SIG content channel 1 is replicated and transmitted in the first, third, fifth, seventh, ninth, eleventh, thirteenth, and fifteenth 20 MHz frequency segments, and U-SIG content channel 2 is replicated and transmitted in the second, fourth, sixth, eighth, tenth, twelfth, fourteenth, and sixteenth 20 MHz frequency segments. When L = 2, in a 160+160 MHz or 320 MHz channel containing eight 40 MHz frequency segments, U-SIG content channel 1 is replicated and transmitted in the first, third, fifth, and seventh 40 MHz frequency segments, and U-SIG content channel 2 is replicated and transmitted in the second, fourth, sixth, and eighth 40 MHz frequency segments.

[0085] According to the present disclosure, the U-SIG field 702 includes three parts: U-SIG1 710, U-SIG2 712, and U-SIG3 714, each containing 26 data bits. U-SIG1 710 includes all version-independent bits and a part of the version-dependent bits, and U-SIG2 712 and U-SIG3 714 include the remaining version-dependent bits. FIGS. 7G and 7H show examples of the formats of U-SIG content channel 1 and U-SIG content channel 2, respectively. U-SIG content channel 1 can include U-SIG1 710 and U-SIG2 712, and U-SIG content channel 2 can include U-SIG1 710 and U-SIG3 714. In one embodiment, U-SIG content channel 1 includes version-dependent bits necessary for interpreting a 20 MHz EHT SU PPDU or an EHT MU PPDU. As an effect of such a configuration where U-SIG1 710 is included in both U-SIG content channels 1 and 2, a legacy STA can decode any U-SIG content channel to obtain version-independent information.

Table 7

[0086] Table 7 shows an example of the format of U-SIG1 710 in the U-SIG field of an EHT SU PPDU or an EHT MU PPDU. U-SIG1 710 can include a PHY Version Identifier field, a UL / DL Flag field, a BSS Color field, a TXOP Duration field, a PPDU Format field, a BW field, an LDPC Extra Symbol Segment field, a Pre-FEC Padding Factor field, and a Disambiguity field. When the PHY Version Identifier field refers to 802.11be, the PPDU Format field is set to "0" when indicating an EHT SU PPDU, "1" when indicating an EHT MU PPDU, and "2" when indicating an EHT TB PPDU. The preamble puncturing mode is only permitted when the BW of the PPDU is 80 MHz or higher. Based on this, the BW field is set to "0" for 20 MHz, "1" for 40 MHz, "2" for 80 MHz non-preamble puncturing mode, "3" for 160 MHz and 80+80 MHz non-preamble puncturing mode, "4" for 320 MHz and 160+160 MHz non-preamble puncturing mode, "5" for 80 MHz preamble puncturing mode, "6" for 160 MHz and 80+80 MHz preamble puncturing mode, and "7" for 320 MHz and 160+160 MHz preamble puncturing mode.

Table 8

[0087] Table 8 shows an example of the format of U-SIG2 712 of the U-SIG field when the PPDU Format field refers to an EHT MU PPDU. In this example, U-SIG2 can include an EHT-SIG Compression field, an EHT-SIG EHT MCS field, an EHT-SIG DCM field, an EHT-SIG Symbols or MU-MIMO Users field, an STBC field, a Doppler field, a GI-LTF Size field, a Number of EHT-LTF Symbols And Midamble Periodicity field, a CRC field, and tail bits. Table 9 shows an example of the format of U-SIG2 712 of the U-SIG field when the PPDU Format field refers to an EHT SU PPDU. In this example, U-SIG2 can include an EHT MCS field, a DCM field, a Beamformed field, a Beam Change field, an STBC field, a Doppler field, a GI-LTF Size field, an NSTS And Midamble Periodity field, a CRC field, and tail bits.

Table 9

[0088] Table 10 shows an example of the format of U-SIG3 714 in the U-SIG field when the PPDU Format field refers to an EHT SU PPDU. In this example, U-SIG3 can include an EHT-LTF Mode field, a Spatial Reuse field, an NSTS MSB (Most Significant Bit) field, a Preamble Puncturing Bitmap field, a CRC field, and tail bits. Due to the fixed bit width of the U-SIG field, the Preamble Puncturing Bitmap field has a fixed bit width of 7 bits. In embodiments where the BW field in U-SIG1 refers to a non-preamble puncturing mode of 20 MHz, 40 MHz, 80 MHz, 160 / 80 + 80 MHz, or 320 / 160 + 160 MHz, the Preamble Puncturing Bitmap field is reserved. When the BW field refers to the 80 MHz preamble puncturing mode, each of the first 3 bits indicates whether a 20 MHz frequency segment other than the primary 20 MHz is punctured, and the remaining 4 bits are reserved. When the BW field refers to the 160 MHz and 80 + 80 MHz preamble puncturing modes, each bit indicates whether a 20 MHz frequency segment other than the primary 20 MHz is punctured. When the BW field refers to the 320 MHz and 160 + 160 MHz preamble puncturing modes, each bit indicates whether a 40 MHz frequency segment other than the primary 40 MHz is punctured. Thus, the above features can enable preamble puncturing of the PPDU transmitted to a single STA using the EHT SU PPDU, which is advantageous.

Table 10

[0089] Table 11 shows an example of the format of U-SIG3 714 in the U-SIG field when the PPDU Format field refers to an EHT MU PPDU, i.e., when it is set to "1". In this example, U-SIG3 can include an EHT-LTF Mode field, a Spatial Reuse field, a Number Of EHT-LTF Symbols MSB field, a CRC field, and tail bits. In the above examples of U-SIG3 for EHT SU PPDUs and MU PPDUs, it is assumed that a 20 MHz EHT PPDU includes a maximum of 8 EHT-LTF symbols that are not subcarrier-interleaved, and that parameterized spatial reuse (PSR)-based spatial reuse operations are not permitted. Therefore, U-SIG3 714 is not necessary to interpret a 20 MHz EHT PPDU. Note that the standard definitions, protocols, and functions of all fields in the U-SIG field described in Tables 10 to 14 are obtained from the 802.11ax specification unless otherwise specified herein, which will be apparent to those of ordinary skill in the art. [Table 11]

[0090] Returning to FIG. 7B, the EHT MU PPDU 704 includes an EHT-SIG field 708. The EHT-SIG field 708 can include the remaining version-dependent bits of the EHT MU PPDU 704. Similar to the EHT-SIG field 504, when an EHT basic PPDU is transmitted to multiple STAs, the EHT-SIG field 708 has a variable MCS and variable length. The EHT-SIG field 708 has a Common field and a User Specific field, which are collectively referred to as the EHT-SIG content channel. The Common field and the User Specific field are encoded separately, and depending on the BW of the EHT MU PPDU 704, there is one or two EHT-SIG content channels. The Common field 716 can include the Common field 2. The User Specific field includes one or more User fields.

[0091] FIG. 7I shows an example of the EHT-SIG content channel of the EHT MU PPDU 704 in more detail. The Common field 716 includes a Common field 2 716b, a CRC field, and a tail bit. The Common field 2 716b can have the same format as the Common field 2 506b of the EHT basic PPDU 500 shown in FIGS. 5J to 5K and Table 14. Similarly, the User Specific field 718 can be composed of one or more User Block fields, and each User Block field includes one or two User fields. For example, the User Specific field 718 can include three User Block fields 1, 2, 3. The User Block field 1 includes two User fields such as User field 1 and User field 2. The User Block field 2 includes two User fields such as User field 3 and User field 4. The User Block field 3 includes one User field 5. One or two CRC fields for error detection and tail bits are added to one or two User fields of each of the User Block fields 1 to 3. In one embodiment, the last User Block can be composed of one or two User fields according to the total number of User fields permitted in the User Specific field 718, which indicates odd or even. The User fields for non-MU-MIMO allocation and MU-MIMO allocation can have the same format as the EHT basic PPDU 500 shown in Table 4 and Table 5, respectively.

[0092] FIG. 8 shows an example of another format of the EHT TB PPDU 800. The EHT TB PPDU 800 has a structure similar to that of the EHT SU PPDU 700. The EHT TB PPDU 800 can include an L-STF field, an L-LTF field, an L-SIG field, an RL-SIG field, a U-SIG field 802, an EHT-STF field, an EHT-LTF field, a Data field, and a PE field. The L-STF field, the L-LTF field, the L-SIG field, the RL-SIG field, and the U-SIG field 802 can be grouped as pre-EHT modulation fields, and the EHT-STF field, the EHT-LTF field, the Data field, and the PE field can be grouped as EHT modulation fields. The EHT TB PPDU 800 is used for trigger-based communication in response to a requested trigger frame. For example, as shown in FIG. 4B, the EHT TB PPDU can be used when the EHT basic PPDU 430 is transmitted to the STAs 424, 426 and includes one or more trigger frames, and the STAs 424, 426 transmit BA frames 434, 435.

[0093] The U-SIG field 802 of the EHT TB PPDU 800 contains one U-SIG content channel. The U-SIG field 802 includes two parts, namely U-SIG1 and U-SIG2, each containing 26 data bits. Table 12 shows an example of the format of the U-SIG field 802 of the EHT TB PPDU 800. The first part of the U-SIG field 802, i.e., U-SIG1, can contain all version-independent bits, including the PHY Version Identifier field, UL / DL Flag field, BSS Color field, TXOP Duration field, PPDU Format field, and BW field. The PHY Version Identifier field is used to identify the exact PHY version starting from 802.11be. The second part of the U-SIG field 802, i.e., U-SIG2, contains the Spatial Reuse 1-4 fields, which are information dependent on the PPDU format, followed by a CRC field and tail bits. Information of some fields of the U-SIG field 802 (e.g., the BW field and the Spatial Reuse 1-4 fields) can be copied from the corresponding trigger frame that requests the transmission of the EHT TB PPDU 800. It should be noted that the standard definitions, protocols, and functions of most fields of the U-SIG field 802 of the EHT TB PPDU 800 are obtained from the 802.11ax specification, which will be obvious to those having ordinary skill in the art.

Table 12

[0094] FIG. 9 shows the configuration of a communication device 900, e.g., an AP, according to various embodiments. Similar to the schematic example of the communication device 300 shown in FIG. 3, the communication device 900 includes a circuit 902, at least one wireless transmitter 910, at least one wireless receiver 912, and at least one antenna 914 (only one antenna is depicted in FIG. 9 for simplicity). The circuit 902 can include at least one controller 908 for use in executing tasks designed for the controller 908 to perform control signaling communication with the assistance of software and hardware. The circuit 902 can further include a transmission signal generator 904 and a reception signal processor 906. The at least one controller 908 can control the transmission signal generator 904 and the reception signal processor 906. The transmission signal generator 904 can include a frame generator 922, a control signaling generator 924, and a PPDU generator 926. The frame generator 922 can generate a MAC frame, e.g., a data frame or a trigger frame. The control signaling generator 924 can generate the control signaling field of the generated PPDU (e.g., the U-SIG field and the EHT-SIG field of an EHT basic PPDU or an EHT MU PPDU, or the U-SIG field of an EHT SU PPDU). The PPDU generator 926 can generate a PPDU (e.g., an EHT basic PPDU, an EHT SU PPDU, or an EHT MU PPDU).

[0095] The receiving signal processor 906 can include a data demodulator / decoder 932 capable of demodulating and decoding the data portion of the received signal (e.g., the Data field of an EHT basic PPDU, an EHT SU PPDU, or an EHT TB PPDU). The receiving signal processor 906 can further include a control demodulator / decoder 934 capable of demodulating and decoding the control signaling portion of the received signal (e.g., the U-SIG field of an EHT basic PPDU, an EHT SU PPDU, or an EHT TB PPDU, the EHT-SIG field of an EHT basic PPDU). At least one controller 908 can include a control signal parser 942 and a scheduler 944. The scheduler 944 can determine RU information and user-specific allocation information for downlink SU or MU transmission allocation, and trigger information for uplink MU transmission allocation. The control signal parser 942 can analyze the control signaling portion of the received signal and the trigger information for uplink MU transmission allocation shared by the scheduler 944, and can assist the data demodulator / decoder 932 in demodulating and decoding the data portion of the received signal.

[0096] FIG. 10 shows the configuration of a communication device 1000, such as an STA, according to various embodiments. Similar to the schematic example of the communication device 300 shown in FIG. 3, the communication device 1000 includes a circuit 1002, at least one wireless transmitter 1010, at least one wireless receiver 1012, and at least one antenna 1014 (only one antenna is depicted in FIG. 10 for simplicity). The circuit 1002 can include at least one controller 1008 for use in executing tasks designed for the controller 1008 to perform control signaling communication with the assistance of software and hardware. The circuit 1002 can further include a transmission signal processor 1004 and a reception signal generator 1006. The at least one controller 1008 can control the transmission signal processor 1004 and the reception signal generator 1006. The reception signal processor 1006 can include a data demodulator / decoder 1032 and a control demodulator / decoder 1034. The control demodulator / decoder 1034 can demodulate and decode the control signaling portion of the received signal (e.g., the U-SIG field and the EHT-SIG field of an EHT basic PPDU or an EHT MU PPDU, or the U-SIG field of an EHT SU PPDU). The data demodulator / decoder 1032 can demodulate and decode the data portion of the received signal (e.g., the data field of an ETH basic PPDU, an EHT SU PPDU, or an EHT MU PPDU) according to its assigned RU information and user-specific assignment information.

[0097] At least one controller 1008 can include a control signal parser 1042, a scheduler 1044, and a trigger information parser 1046. The control signal parser 1042 can analyze the control signaling portion of the received signal (e.g., the U-SIG field and the EHT-SIG field of an EHT basic PPDU or an EHT MU PPDU, or the U-SIG field of an EHT SU PPDU) and assist the data demodulator / decoder 1032 in demodulating and decoding the data portion of the received signal (e.g., the data field of an EHT basic PPDU, an EHT SU PPDU, or an EHT MU PPDU). The trigger information parser 1048 can analyze trigger information for its own uplink allocation from the received trigger frame included in the data portion of the received signal. The transmission signal generator 1004 can include a control signaling generator 1024 capable of generating the control signaling field of the generated PPDU (e.g., the U-SIG field of an EHT basic PPDU, an EHT SU PPDU, or an EHT TB PPDU). The transmission signal generator 1004 can further include a PPDU generator 1026 that generates a PPDU (e.g., an EHT basic PPDU, an EHT SU PPDU, or an EHT TB PPDU). The transmission signal generator 1004 can further include a frame generator 1022 that generates a MAC frame (e.g., a data frame).

[0098] As described so far, embodiments of the present disclosure provide an advanced communication system, communication method, and communication apparatus for performing control signaling in a very high throughput MIMO WLAN network, and improve the spectral efficiency in the MIMO WLAN network.

[0099] The present disclosure can be implemented by software, by hardware, or by software cooperating with hardware. Each functional block used in the description of each of the above-described embodiments can be implemented in part or in whole by an LSI such as an integrated circuit, and each process described in each embodiment can be controlled in part or in whole by the same LSI or a combination of LSIs. The LSI can be formed individually as a plurality of chips, or can be formed as one chip so as to include part or all of the functional blocks. The LSI can include a data input / output section coupled to itself. Depending on the degree of integration, the LSI is also referred to as an IC, a system LSI, a super LSI, or an ultra LSI. However, the technology for implementing the integrated circuit is not limited to the LSI, and can be implemented by using a dedicated circuit, a general-purpose processor, or a dedicated processor. Furthermore, an FPGA (Field Programmable Gate Array) that can be programmed after the manufacture of the LSI, or a reconfigurable processor that can reconfigure the connection and setting of circuit cells arranged inside the LSI can also be used. The present disclosure can be implemented as digital processing or analog processing. As a result of the progress of semiconductor technology or another derived technology, if future integrated circuit technology replaces the LSI, functional blocks can be integrated using that future integrated circuit technology. Biotechnology can also be applied.

[0100] The present disclosure can be implemented by any type of device, apparatus, or system having a communication function, referred to as a communication device.

[0101] The communication device can include a transceiver and a processing / control circuit. The transceiver can include a receiver and a transmitter, and / or can function as a receiver and a transmitter. The transceiver (as a transmitter and a receiver) can include an RF (radio frequency) module including an amplifier, an RF modulator / demodulator, and one or more antennas.

[0102] Some non-limiting examples of such communication devices include telephones (e.g., mobile phones, smartphones), tablets, personal computers (PCs) (e.g., laptops, desktops, notebooks), cameras (e.g., digital still / video cameras), digital players (digital audio / video players), wearable devices (e.g., wearable cameras, smartwatches, tracking devices), game consoles, e-book readers, remote medical / telemedicine devices, vehicles providing communication functions (e.g., automobiles, airplanes, ships), and various combinations thereof.

[0103] The communication device is not limited to being portable or mobile, and can include any type of device, apparatus, or system that is non-portable or stationary, such as smart home devices (e.g., household appliances, lighting, smart meters, control panels), vending machines, and any other "things" within the network of the "Internet of Things (IoT)".

[0104] Communication can include exchanging data, for example, through cellular systems, wireless LAN systems, satellite systems, and various combinations thereof.

[0105] The communication device can include devices such as a controller or a sensor coupled to a communication device that performs the communication functions described in this disclosure. For example, the communication device can include a controller or a sensor that generates a control signal or a data signal used by a communication device that performs the communication functions of the communication device.

[0106] The communication device can further include infrastructure facilities, such as a base station, an access point, and any other device, apparatus, or system that communicates with or controls a device such as the device in the non-limiting example above.

[0107] Although some characteristics of various embodiments are described with reference to the device, the corresponding characteristics also apply to the methods of various embodiments, and vice versa.

[0108] Those skilled in the art will understand that numerous changes and / or modifications can be made to the present disclosure shown in specific embodiments without departing from the spirit or scope of the present disclosure as broadly described. Therefore, the embodiments herein are considered to be illustrative in all respects and not restrictive of the present invention. [Table 13] [Table 14] [Table 15]

Claims

1. A communication device, a circuit for generating an Extremely High Throughput Physical layer Protocol Data Unit (EHT PPDU) including a Universal Signal (U-SIG) field having a first part (U-SIG1) and a second part (U-SIG2) each containing the same number of data bits, wherein the data bits of the U-SIG2 do not include version-independent bits, the circuit, a transmitter for transmitting the EHT PPDU, comprising, the EHT PPDU further has an EHT Signal (EHT-SIG) field including a common field and a user-specific field that are referred to together as an EHT-SIG content channel, both the U-SIG field and the EHT-SIG field are present in the EHT PPDU transmitted to a single STA or multiple STAs, when the EHT PPDU is transmitted to the single STA, the user-specific field has a single user field, the EHT PPDU includes a single EHT content channel regardless of the bandwidth of the EHT PPDU, and the single EHT content channel is replicated for each 20 MHz frequency segment, A communication device.

2. In non-trigger-based communication with one or more other STAs, the U-SIG field has a single format, The communication device according to claim 1.

3. In non-trigger-based communication, the EHT-SIG field includes a part of version-dependent bits, The communication device according to claim 1.

4. When the EHT PPDU is transmitted to the plurality of STAs, the common field includes a common field 1 and a common field 2 that are individually encoded on the EHT content channel. The communication device according to claim 1.

5. When the EHT PPDU is transmitted to the single STA, the EHT-SIG field includes a preamble puncturing bitmap. The communication device according to claim 3.

6. The preamble puncturing bitmap has a variable bit width according to the bandwidth of the EHT PPDU. The communication device according to claim 5.

7. The U-SIG field includes information for interpreting the EHT-SIG field. The communication device according to claim 3.

8. A communication method of a communication device, comprising: generating an Extremely High Throughput Physical layer Protocol Data Unit (EHT PPDU) including a Universal Signal (U-SIG) field having a first part (U-SIG1) and a second part (U-SIG2), each including the same number of data bits, wherein the data bits of the U-SIG2 do not include version-independent bits; transmitting the EHT PPDU; and the EHT PPDU further has an EHT signal (EHT-SIG) field including a common field and a user-specific field that are referred to together as an EHT-SIG content channel, both the U-SIG field and the EHT-SIG field are present in the EHT PPDU transmitted to a single STA or a plurality of STAs, When the EHT PPDU is transmitted to the single STA, the user-specific field has a single user field, the EHT PPDU includes a single EHT content channel regardless of the bandwidth of the EHT PPDU, and the single EHT content channel is replicated for each 20 MHz frequency segment. Communication method.

Images