Station and access point in wireless local area network system, and operation methods thereof

Abstract

This invention provides a base station (STA) communicating with an access point (AP) in a wireless local area network (WLAN) system, comprising: a transceiver configured to support the transmission and reception of signals within at least a first bandwidth, and receiving a first physical layer protocol data unit (PPDU) conforming to a second bandwidth greater than the first bandwidth; and a processing circuitry configured to support a bandwidth wider than the first bandwidth by obtaining a second PPDU allocated to the STA within the first bandwidth from the first PPDU. The processing circuitry is configured to control the transceiver to transmit to the AP performance information indicating a first MCS among a plurality of candidate modulation and coding schemes (MCSs) that can be supported in the wider bandwidth according to the capabilities of the STA.

Description

Technical Field

[0001] This disclosure is generally related to wireless communication, and more particularly, to base stations and access points that both perform communication based on a wireless local area network (WLAN), and methods of operating the same. Cross - Reference to Related Applications

[0002] This application is based on and claims priority to the following: U.S. Provisional Patent Application No. 63 / 283,345, filed on November 26, 2021; U.S. Provisional Patent Application No. 63 / 265,946, filed on December 23, 2021, with the United States Patent and Trademark Office; and Korean Patent Application No. 10 - 2022 - 0085874, filed on July 12, 2022, with the Korean Intellectual Property Office. The disclosures of the above - mentioned patent applications are incorporated herein by reference in their entireties. Background Art

[0003] In the physical (PHY) layer of the next - generation WLAN that is compliant with Institute for Electrical and Electronic Engineer (IEEE) 802.11ax WLAN, various techniques have been proposed to improve spectral efficiency and throughput. For example, a wider bandwidth (e.g., a bandwidth of 320 megahertz) for increasing data transmission rate and a multi - resource unit (RU) allocation technique for bundling and transmitting RUs to increase spectral efficiency have been proposed.

[0004] For example, when the bandwidth of a physical packet data unit (PPDU) transmitted by a traditional WLAN - based communication system (as opposed to the enhanced "traditional" described herein) is the same as the bandwidth that can be supported by a station (STA), an access point (AP) supports multiple accesses. In the proposed update to the traditional system, when the bandwidth of the PPDU transmitted by the AP exceeds the bandwidth that can be supported by the STA, the STA can obtain a PPDU (e.g., a sub - PPDU) allocated to itself from the received PPDU, thereby increasing spectral efficiency. An STA that performs the above operation can be defined as supporting a wider bandwidth. Research is ongoing to improve the efficiency and performance of the STA when supporting a wider bandwidth. Summary of the Invention

[0005] Embodiments of the present invention concept provide a station (STA) and an access point (AP) in a WLAN system, where the STA transmits performance information (capability information) to the AP with a bandwidth wider than that defined in the traditional WLAN protocol. In addition, the AP generates a PPDU suitable for the STA based on the performance information of the STA and transmits the PPDU to the STA. Methods for operating the STA and the AP are described.

[0006] According to an aspect of the present invention concept, there is provided an STA communicating with an AP in a WLAN system, the STA comprising: a transceiver configured to support transmission and reception of signals within at least a first bandwidth and receiving a first PPDU conforming to a second bandwidth greater than the first bandwidth; and processing circuitry configured to support a bandwidth wider than the first bandwidth by obtaining, from the first PPDU, a second PPDU allocated to the STA within the first bandwidth. The processing circuitry is configured to control the transceiver to transmit to the AP performance information indicating a first MCS among a plurality of candidate modulation and coding schemes (MCSs) that can be supported by the STA in the wider bandwidth according to the capabilities of the STA.

[0007] According to another aspect of the present invention concept, there is provided an AP for communicating with an STA, the STA supporting transmission and reception within at least a first bandwidth defined by a traditional WLAN protocol in a WLAN system, the AP comprising: a transceiver configured to receive from the STA performance information indicating one or more MCSs among candidate MCSs that can be supported by the STA in a second bandwidth wider than the first bandwidth and transmit a first PPDU to the STA; and processing circuitry configured to select one MCS from the one or more MCSs based on the performance information and the channel state with the STA and generate a second PPDU based on the selected one MCS. The first PPDU includes the second PPDU and conforms to the second bandwidth.

[0008] According to another aspect of the present invention concept, there is provided an operating method for a STA communicating with an AP in a WLAN system, the operating method comprising: transmitting to the AP performance information indicating one or more MCSs supportable in a second bandwidth according to the capabilities of the STA among a plurality of candidate MCSs, wherein the second bandwidth is wider than a first bandwidth defined by a conventional WLAN protocol; receiving a first PPDU from the AP, in one or more MCSs, an MCS that conforms to the second bandwidth and the performance information has been applied to the first PPDU; and obtaining from the first PPDU a second PPDU allocated to the STA. The second PPDU may be allocated to the STA within the first bandwidth.

[0009] According to another aspect of the present invention concept, there is provided an operating method for an AP communicating with a STA in a WLAN system, the operating method comprising: receiving performance information from the STA, the performance information indicating a first MCS supportable in a wider bandwidth according to the performance of the STA among a plurality of MCSs; selecting, based on the performance information and the channel state with the STA, a first MCS from the first MCS; generating a second PPDU conforming to the first bandwidth based on the selected first MCS; and transmitting to the STA a first PPDU including the second PPDU and conforming to a second bandwidth greater than the first bandwidth.

[0010] In another aspect, a STA communicating with an AP in a WLAN system includes a transceiver and processing circuitry. The transceiver is configured to support transmission and reception of signals within at least a first bandwidth defined by a conventional WLAN protocol, and receives a first PPDU conforming to a second bandwidth greater than the first bandwidth. The processing circuitry is configured to support the second bandwidth by: controlling the transceiver to transmit to the AP performance information indicating one or more MCSs among a plurality of candidate MCSs, wherein the one or more MCSs can be supported by the STA in the second bandwidth according to the capabilities of the STA. The processing circuitry obtains a second PPDU from the first PPDU, wherein the second PPDU is allocated to the STA and is configured by the AP at least based on the performance information transmitted by the transceiver.

[0011] In another aspect, a computer program product is for any of the STAs outlined above and includes a non-transitory computer-accessible storage medium, which includes code for implementing the operating method of the STA. Brief Description of the Drawings

[0012] Embodiments will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which: FIG. 1 is a block diagram of a wireless communication system according to an embodiment. FIG. 2 is a block diagram of a wireless communication system according to an embodiment. FIGS. 3A and 3B are block diagrams for explaining the operation of a wireless communication system according to an embodiment. FIG. 4 is a graph illustrating the relationship between the error rate of a physical packet data unit (PPDU) allocated to a station (STA) supporting a wider bandwidth and the modulation and coding scheme (MCS). FIG. 5A is an enhanced view showing an extremely high throughput (EHT) capability element format for transmitting performance information according to an embodiment, and FIGS. 5B and 5C are views showing an 'EHT PHY capability information' field for transmitting performance information according to an embodiment. FIG. 6 is a flowchart of an operating method of an access point (AP) and an STA according to an embodiment. FIG. 7A is a view showing first performance information according to an embodiment, and FIG. 7B is a view for explaining the performance of an STA indicated by the first performance information in FIG. 7A. FIG. 8A is a view showing first performance information according to an embodiment, and FIG. 8B is a view for explaining the performance of an STA indicated by the first performance information in FIG. 8A. FIG. 9A is a view showing first performance information according to an embodiment, and FIG. 9B is a view for explaining the performance of an STA indicated by the first performance information in FIG. 9A. FIG. 10A is a view showing first performance information according to an embodiment, and FIG. 10B is a view for explaining the performance of an STA indicated by the first performance information in FIG. 10A. FIGS. 11A, 11B, and 11C are views showing first performance information according to an embodiment. FIG. 12 is a flowchart of an embodiment of operation S120 in FIG. 6. FIG. 13A is a view showing a'supported EHT-MCS and number of spatial streams (NSS) set' field for transmitting first performance information according to an embodiment; FIGS. 13B and 13C are views for explaining the performance of an STA indicated by the first performance information. FIG. 14 is a view showing a'supported EHT-MCS and NSS set' field for transmitting first performance information according to an embodiment. FIG. 15 is a flowchart of an embodiment of operation S120 in FIG. 6. FIG. 16A is a view showing first performance information according to an embodiment, and FIG. 16B is a view for explaining the performance of an STA indicated by the first performance information in FIG. 16A. FIG. 17 is a flowchart of an operation method of an AP according to an embodiment. FIGS. 18A and 18B are views for explaining a method of scheduling a second PPDU of a STA having a wider bandwidth allocated to support an AP according to an embodiment. FIG. 19 is a conceptual diagram of an Internet of Things (IoT) network system to which an embodiment is applied. Embodiments

[0013] Embodiments will now be described in the context of a wireless communication system based on a wireless local area network (WLAN). However, the inventive concept can be applied to other wireless communication systems having similar technical aspects or channel configurations, such as cellular communication systems, such as next-generation communication, new radio (NR), long term evolution (LTE), LTE-advanced (LTE-A), wireless broadband (WiBro), or global system for mobile communication (GSM), 5G, and 6G, or local area communication systems, such as Bluetooth or near field communication (NFC).

[0014] Herein, the “performance information” of a STA may refer to information related to the ability of the STA to communicate with an AP. An example of performance information (sometimes referred to herein as “first performance information”) is an indication of the MCS that the STA can use to successfully communicate on a predetermined bandwidth that is wider than the bandwidth specified by a conventional WLAN protocol.

[0015] Herein, the term “normal bandwidth” may refer to the bandwidth specified by a conventional WLAN protocol such as the 802.11ax protocol.

[0016] FIG. 1 is a block diagram showing a wireless communication system 100 according to an embodiment. The wireless communication system 100 may include multiple access points (APs) 101 and 103 and multiple stations (STAs) 111 to 114. The APs 101 and 103 may communicate with at least one network 130, such as the Internet, an Internet protocol (IP) network.

[0017] AP 101 and AP 103 can provide wireless connections to network 130, enabling STAs 111 to 114 within respective coverage areas 120 and 125 of AP 101 and AP 103 to use communication services. For example, AP 101 and AP 103 can communicate with each other using wireless fidelity (WiFi) or other WLAN communication technologies. AP 101 and AP 103 can communicate with STAs 111 to 114 by using WiFi or other WLAN communication technologies.

[0018] For reference, depending on the network type, other well-known terms such as "router" and "gateway" can replace AP. An AP in a WLAN can be provided for a wireless channel. According to the operation, an AP can be identified as an STA for communicating with another AP. An AP according to the concepts of the present invention can also be referred to as a device, a wireless device, a communication device, or the like.

[0019] In addition, depending on the network type, an STA can be used to replace another well-known term, such as a mobile base station, a user base station, a remote terminal, a user equipment, a wireless terminal, a user device, or a user. For convenience, the prefix term "STA" used herein is used to represent a remote wireless device that wirelessly accesses an AP or accesses a wireless channel within a WLAN. According to the operation, an STA can be identified as an AP for the other STA side. An STA according to the concepts of the present invention can also be referred to as a device, a wireless device, a communication device, or the like.

[0020] According to an embodiment, AP 101 and AP 103 can be respectively included in different devices, or can be included in one device (AP multiple link device (MLD)). STAs 111 to 114 can be respectively included in different devices, or can be included in one device (non-AP MLD).

[0021] The dashed lines illustrate the approximate extents of coverage areas 120 and 125. For purposes of explanation and illustration, coverage areas 120 and 125 are illustrated as generally circular. However, depending on the settings of AP 101 and AP 103, the coverage areas 120 and 125 associated with AP 101 and AP 103 can have different shapes reflecting various changes in the wireless environment related to natural or artificial obstacles, or can have other shapes including irregular shapes.

[0022] FIG. 1 only illustrates an example of the wireless communication system 100, but the embodiments are not limited thereto.

[0023] For example, the wireless communication system 100 may include any number of APs and any number of STAs that are appropriately configured. The AP 101 can directly communicate with any number of STAs. Specifically, the AP 101 can provide a wireless broadband connection to the STAs 111 to 114 with the network 130.

[0024] Similarly, each of the APs 101 and 103 can directly communicate with the network 130 and can provide a wireless broadband connection to the STAs 111 to 114 with the network 130. In addition, the APs 101 and 103 can implement connections with various external networks, such as an external telephone network or a data network. To describe the embodiments, the respective configurations and operations of the AP 101 and the STA 111 are mainly described, and the embodiments to be described are applicable to the other APs 103 and the other STAs 112 to 114.

[0025] According to an embodiment, the STA 111 can transmit its own performance information for supporting a ( "second") bandwidth that is wider than the bandwidth ( "first bandwidth") of the traditional WLAN protocol to the AP 101 to perform enhanced WLAN-based communication (enhancement relative to the traditional WLAN protocol). Here, "traditional" refers to previously deployed technologies, such as the IEEE 802.11ax standard (protocol). In this document, an STA that supports a wider (second) bandwidth may refer to an STA that can obtain a second physical packet data unit (PPDU) allocated to itself from a first PPDU that conforms to the second bandwidth in response to a first PPDU.

[0026] In this document, the first PPDU refers to a PPDU that conforms to the second bandwidth during the transmission and reception of a signal, and the second PPDU refers to a PPDU allocated to an STA within the first PPDU. The first PPDU may further include at least one of the PPDUs allocated to the other STAs 112 to 114.

[0027] The STA 111 can sample the received first PPDU at a sampling rate that is an integer multiple of the sampling rate that conforms to the maximum supportable first bandwidth in order to support a wider bandwidth, can filter the sampling result using a down-conversion filter having a predetermined passband, and can perform downsampling on the filtered result at a sampling rate that conforms to the first bandwidth, thereby obtaining the second PPDU.

[0028] For example, when the first bandwidth is 80 MHz and the second bandwidth is 160 MHz, STA 111 can perform sampling on the first PPDU at a sampling rate that is twice the sampling rate conforming to 80 MHz, perform filtering on the result of the sampling using a down-conversion filter having a passband conforming to 80 MHz, and perform downsampling on the result of the filtering at a sampling rate conforming to 80 MHz, thereby obtaining a second PPDU.

[0029] When the first bandwidth is 80 MHz and the second bandwidth is 320 MHz, STA 111 can perform a first sampling on the first PPDU at a sampling rate that is four times the sampling rate conforming to 80 MHz, perform a first filtering on the result of the first sampling using a down-conversion filter having a passband conforming to 160 MHz, and perform downsampling on the result of the first filtering at a sampling rate conforming to 160 MHz. STA 111 can perform a second sampling on the result of the first downsampling at a sampling rate that is twice the sampling rate conforming to 80 MHz, perform filtering on the result of the second sampling using a down-conversion filter having a passband conforming to 80 MHz, and perform a second downsampling on the result of the second filtering at a sampling rate conforming to 80 MHz, thereby obtaining a second PPDU.

[0030] When STA 111 performs filtering and downsampling to obtain a second PPDU from the first PPDU, side lobes can be generated by a non-ideal down-conversion filter, and the side lobes can cause frequency aliasing during the downsampling process, thereby degrading the quality of the second PPDU. Additionally, side lobes can occur due to the limited performance of STA 111 (e.g., the quality of the sampling clock), thereby degrading the quality of the second PPDU.

[0031] When the performance of STA 111 is good, even when a modulation and coding scheme (MCS) with a high data rate is applied to the second PPDU, STA 111 can successfully obtain the second PPDU. However, when the performance of STA 111 is poor and an MCS with a high data rate is applied to the second PPDU, STA 111 may not be able to obtain the second PPDU. Herein, an STA that obtains a PPDU can also be interpreted as successfully extracting data from the PPDU by successfully demodulating and / or decoding the PPDU. Therefore, when AP 101 generates a second PPDU, STA 111 can transmit its own performance information to AP 101 to consider the performance of STA 111 in a wider bandwidth. According to an embodiment, the performance of STA 111 can be determined according to the sharpness of the down-conversion filter. According to some embodiments, the performance of STA 111 can be determined according to the quality of the sampling clock. In other examples, the performance of STA 111 is determined by various factors used in operations performed to support wider bandwidth operations.

[0032] According to an embodiment, the performance information transmitted from the STA 111 to the AP 101 may include first performance information indicating a first MCS among a plurality of MCSs that the STA 111 can support in a wider bandwidth according to the performance of the STA 111. The AP 101 may select a first MCS from the first MCS based on the first performance information, and may generate a second PPDU allocated to the STA 111 based on the selected first MCS. The AP 101 may transmit a first PPDU including the second PPDU to the STA 111.

[0033] According to some embodiments, the performance information may include second performance information indicating whether the STA 111 is capable of supporting a wider bandwidth. The AP 101 may transmit a first PPDU including a second PPDU allocated to the STA 111 by checking that the STA 111 is capable of supporting a wider bandwidth based on the second performance information.

[0034] According to an embodiment, the performance information may be transmitted from the STA 111 to the AP 101 via at least one of the fields defined in the "IEEE P802.11be standard" (interchangeably, only "IEEE P802.11be"). IEEE P802.11be is a framework for the next-generation WLAN standard (following IEEE 802.11ax), which is currently under development but some aspects have been defined. For example, due to the performance of the non-compliant STA 111, the performance information may be transmitted via some IEEE P802.11be fields (empty fields) that do not have information. Alternatively, the performance information is transmitted via the'reserved' sub-fields included in some of the fields of IEEE P802.11be.

[0035] The STA 111 according to an embodiment may provide performance information related to a wider bandwidth to the AP 101, so that the AP 101 may select an MCS suitable for the performance of the STA 111 and generate a second PPDU allocated to the STA 111. Therefore, the STA 111 may effectively obtain the second PPDU from the first PPDU conforming to a second bandwidth wider than the traditional first bandwidth, and thus, the communication performance of the STA 111 supporting a wider bandwidth may be improved.

[0036] According to some embodiments, the STA 111 may include a computer program product for communicating with the AP 101. The computer program product may include a non-transitory computer-accessible storage medium (non-transitory computer-readable medium), where the non-transitory computer-accessible storage medium may include code executable by at least one processor such that the STA 111 may perform operations according to the embodiments. The at least one processor may correspond to the processing circuitry 223 of FIG. 2.

[0037] FIG. 2 is a block diagram of a wireless communication system 200 according to an embodiment. The block diagram of FIG. 2 shows the AP 210 and the STA 220 communicating with each other in the wireless communication system 200. Each of the AP 210 and the STA 220 in FIG. 2 may be any device communicating in the wireless communication system 200 and may be referred to as a device for wireless communication. According to some embodiments, the AP 210 may be one of a plurality of APs included in the AP MLD, and the STA 220 may be one of a plurality of STAs included in the non-AP MLD.

[0038] Referring to FIG. 2, the AP 210 may include an antenna 211, a transceiver 212, and processing circuitry 213. According to some embodiments, the antenna 211, the transceiver 212, and the processing circuitry 213 may be respectively included in one package or may be included in different packages. The STA 220 may include an antenna 221, a transceiver 222, and processing circuitry 223. Hereinafter, redundant descriptions between the AP 210 and the STA 220 are omitted.

[0039] The antenna 211 may receive signals from the STA 220 and provide the signals to the transceiver 212, and may transmit the signals provided from the transceiver 212 to the STA 220. According to some embodiments, the antenna 211 may include multiple antennas for multiple input multiple output (MIMO). According to some embodiments, the antenna 211 may also include a phase array for beamforming.

[0040] The transceiver 212 may process the signals received from the STA 220 via the antenna 211 and may provide the processed signals to the processing circuitry 213. The transceiver 212 may process the signals provided from the processing circuitry 213 and output the processed signals via the antenna 211. The transceiver 212 may include analog circuits such as low noise amplifiers, mixers, filters, power amplifiers, oscillators, etc. The transceiver 212 may process the signals received from the antenna 211 and / or the signals received from the processing circuitry 213 under the control of the processing circuitry 213.

[0041] The processing circuit system 213 can extract the information transmitted by the STA 220 by processing the signals received from the transceiver 212. For example, the processing circuit system 213 can extract the information by demodulating and / or decoding the signals received from the transceiver 212. The processing circuit system 213 can generate a signal containing the information to be transmitted to the STA 220 and provide the signal to the transceiver 212. For example, the processing circuit system 213 can provide a signal generated by encoding and / or modulating the data to be transmitted to the STA 220 to the transceiver 212. According to some embodiments, the processing circuit system 213 can include: programmable components, such as a central processing unit (CPU) or a digital signal processor (DSP); reconfigurable components, such as a field programmable gate array (FPGA); or components providing fixed functions, such as an intellectual property (IP) core. According to some embodiments, the processing circuit system 213 can include or access a memory storing data and / or a series of instructions. Herein, the transceiver 212 and / or the processing circuit system 213 performing the operations can simply be referred to as the AP 210 performing the corresponding operations. Therefore, the operations performed by the AP 210 can be performed by the transceiver 212 and / or the processing circuit system 213 included in the AP 210, and the operations performed by the STA 220 can be performed by the transceiver 221 and / or the processing circuit system 224 included in the STA 220.

[0042] The STA 220 can support transmission / reception up to a first bandwidth (or alternatively, within at least the first bandwidth) via the antenna 221 and the transceiver 222, and the STA 220 can receive a first PPDU conforming to a second bandwidth wider than the first bandwidth by using the antenna 221 and the transceiver 222. The processing circuit system 223 can obtain a second PPDU allocated to the STA 220 from the first PPDU by performing operations supporting a wider bandwidth.

[0043] The processing circuit system 223 can manage the performance information 224 related to supporting a wider bandwidth. The performance information 224 can include at least one of first performance information indicating the performance of the STA 220 when the STA 220 performs operations for supporting a wider bandwidth and second performance information indicating whether the STA 220 can support a wider bandwidth.

[0044] The first performance information may include information indicating a first MCS among multiple candidate MCSs (hereinafter simply referred to as "multiple MCSs") that the STA 220 can support when the STA 220 performs operations to support a wider bandwidth. For example, the multiple MCSs may include the MCSs defined from index 0 to index 15 in the P802.11be standard.

[0045] The STA 220 may successfully obtain a second PPDU generated based on one of the first MCSs from the first PPDU, but may not be able to obtain a second PPDU generated based on any of the remaining MCSs (other than the first MCS). Therefore, the STA 220 can inform the AP 210 of its capability status (the status of the STA 220) by transmitting the first performance information to the AP 210.

[0046] For example, the first performance information may include bits indicating which of the multiple MCSs can be supported. This will be described in detail below with reference to FIGS. 7A and 7B.

[0047] For example, the first performance information may include bits indicating whether each of the specific MCSs among the multiple MCSs having a data rate equal to or greater than a reference value can be supported. This will be described in detail below with reference to FIGS. 8A and 8B.

[0048] For example, the first performance information may include bits indicating a specific MCS having the highest data rate among the first MCSs. This will be described in detail below with reference to FIGS. 9A and 9B.

[0049] For example, the first performance information may include at least one bit indicating an offset from a specific MCS having the highest data rate among the "second MCSs". Herein, the "second MCSs" may correspond to the MCSs that the STA 220 can support when the STA 220 receives a third PPDU with a third bandwidth that is less than or equal to the first bandwidth that can be supported for transmission and reception from among the multiple MCSs. In other words, the second MCSs may correspond to the MCSs that the STA 220 can support when the STA 220 receives a third PPDU that conforms to its own transmission / reception performance. This will be described in detail below with reference to FIGS. 10A to 11C.

[0050] For example, the first performance information may include at least one bit indicating an offset of a specific MCS having the highest data rate among at least one of the plurality of MCS groups. Herein, the plurality of MCS groups may be classified by grouping MCSs having the same maximum number of spatial streams in the second MCS. This will be described in detail below with reference to FIGS. 13A to 13C.

[0051] For example, the first performance information may include information indicating the first MCS corresponding to values that the second bandwidth may have respectively. Specifically, when the maximum supportable first bandwidth of the STA 220 is 80 MHz and the second bandwidth is 160 MHz or 320 MHz, the first performance information may include multiple pieces of information respectively indicating the first MCS when supporting the wider bandwidth corresponding to 160 MHz and the first MCS when supporting the wider bandwidth corresponding to 320 MHz.

[0052] For example, the first performance information may include information indicating an additional suppression level that the STA 220 can support relative to the adjacent channel suppression level associated with the plurality of MCSs. This will be described in detail below with reference to FIGS. 16A and 16B.

[0053] According to an embodiment, the performance information 224 may be stored in the non-volatile memory of the STA 220 and may be read by the processing circuit system 223. The processing circuit system 223 may control the transceiver 222 to transmit a signal (the "transmitted performance information") including the read performance information 224 to the AP 210. According to some embodiments, the processing circuit system 223 may include a first circuit for managing the performance information 224 and a second circuit for controlling the transceiver 222 to transmit the performance information 224 to the AP 210. In other words, the first circuit for managing the performance information may be logically and / or physically different from the second circuit for controlling the transceiver 222.

[0054] According to an embodiment, the processing circuitry 213 of the AP 210 may include a scheduler 214, which may select an MCS from the MCSs that can be supported based on the performance information received from the STA 220 via the antenna 211 and the transceiver 212. The scheduler 214 may generate a second PPDU allocated to the STA 220 based on the selected MCS. The scheduler 214 may estimate the channel state between the AP 210 and the STA 220 or receive information about the estimated channel state from the STA 220, and may select one of the first MCSs by further considering the estimated channel state. For this purpose, in an example, when the estimated channel state is considered good according to at least one predetermined criterion, the scheduler 214 may generate the second PPDU by selecting the MCS with the highest data rate among the MCSs that can be supported. However, when the estimated channel state is in a bad state according to at least one predetermined criterion, the scheduler 214 may generate the second PPDU by selecting the MCS with a low data rate among the MCSs that can be supported according to the degree of the bad channel state. In other examples, the scheduler 214 may select one of the MCSs based on only one of the performance information 224 or the channel state to generate the second PPDU.

[0055] According to an embodiment, the scheduler 214 may allocate the second PPDU to the remaining RUs among the multiple RUs included in the band except for the RUs located at the boundary of the band supported by the STA 220. In other words, because the side lobes and frequency overlap described above with reference to FIG. 1 are caused by the subcarriers located at the boundary of the band, the second PPDU may not be allocated to the RUs including such subcarriers. This will be described in detail below with reference to FIGS. 18A and 18B.

[0056] According to an embodiment, the scheduler 214 may include the second PPDU, and may transmit the first PPDU conforming to the second bandwidth to the STA 220 by using the antenna 211 and the transceiver 212. The first PPDU may further include the PPDUs allocated to at least one other STA (not shown).

[0057] According to some embodiments, the processing circuitry 213 and the processing circuitry 223 may be referred to as a processor, a controller, or the like.

[0058] FIGS. 3A and 3B are block diagrams for explaining the operation of a wireless communication system 300 according to an embodiment.

[0059] Referring to FIG. 3A, the wireless communication system 300 may include an AP 310, a first STA 320, and a second STA 330. The first STA 320 may support at least a first bandwidth BW1 during transmission and reception, and the second STA 330 may support at least a second bandwidth BW2 during transmission and reception.

[0060] According to an embodiment, the first STA 320 may transmit first performance information indicating a first MCS among a plurality of candidate MCSs that can be supported in a wider bandwidth to the AP 310. The AP 310 may generate a first PPDU based on the first performance information, transmit the first PPDU to the first STA 320 via a first channel CH1, and transmit the first PPDU to the second STA 330 via a second channel CH2. The first PPDU conforming to the second bandwidth BW2 may include a second PPDU allocated to the first STA 320. Accordingly, the first PPDU may be understood as a "composite PPDU" or an "aggregated PPDU", and may include a third PPDU allocated to the second STA 330. When the first PPDU includes the second and third PPDUs, it may be understood as a "composite PPDU" or an "aggregated PPDU", in which at least two PPDUs allocated to different respective STAs are transmitted within the same time frame, for example, together with a first set of OFDM subcarriers representing the second PPDU and a second set of OFDM subcarriers representing the third PPDU. In one example, the second PPDU conforms to the first bandwidth BW1 (e.g., the second PPDU is represented by OFDM subcarriers distributed only within the first bandwidth BW1). In other examples, the second PPDU conforms to a bandwidth between the first bandwidth and the second bandwidth.

[0061] The second PPDU may be generated by applying an MCS selected according to the first performance information, where the selected MCS may be the same as or different from the MCS applied to the third PPDU. According to some embodiments, the same MCS may be controlled to be used for generating the second and third PPDUs included in the first PPDU. For example, when the MCS corresponding to the second PPDU is different from the MCS corresponding to the third PPDU, the MCS with a low data rate among the MCSs may be controlled to be commonly used for generating the second and third PPDUs. As another example, when the MCS corresponding to the second PPDU is different from the MCS corresponding to the third PPDU, the MCS with a high data rate among the MCSs may be controlled to be commonly used for generating the second and third PPDUs.

[0062] The first STA 320 may transmit "second performance information" to the AP 310 indicating whether a wider (second) bandwidth can be supported. Referring to FIG. 3B, when the first STA 320 cannot support the wider bandwidth and indicates such lack of ability with the second performance information, the AP 310 may transmit a second PPDU conforming to the first bandwidth BW1 and a third PPDU conforming to the second bandwidth BW2 to the first STA 320 and the second STA 330 in sequence, respectively. Alternatively, the second and third PPDUs are transmitted simultaneously (e.g., using different respective OFDM subcarriers as previously mentioned).

[0063] FIG. 4 is a graph showing the relationship between the error rate of a PPDU allocated to a STA supporting a wider bandwidth and the MCS. In FIG. 4, MCS0, MCS7, MCS9, and MCS11 refer to the MCSs with indexes 0, 7, 9, and 11 defined in P802.11be. The modulation scheme and coding rate of MCS0 are binary phase shift keying (BPSK) and 1 / 2, the modulation scheme and coding rate of MCS7 are 64 quadrature amplitude modulation (QAM) and 5 / 6, the modulation scheme and coding rate of MCS9 are 256-QAM and 5 / 6, and the modulation scheme and coding rate of MCS11 are 1024-QAM and 5 / 6. SU refers to a single user, and MU refers to multiple users. 'TX = RX = 80' means that the bandwidth of the PPDU transmitted by the AP is 80 MHz, and the STA supports reception up to 80 MHz. 'TX = 160 / RX = 80' means that the bandwidth of the PPDU transmitted by the AP is 160 MHz and the STA supports reception up to 80 MHz. In this case, the STA performs operations for supporting the wider bandwidth.

[0064] Referring to FIG. 4, it can be seen that when applying one of MCS7, MCS9, and MCS11 in the wider bandwidth to the PPDU allocated to the STA, even when the signal to noise ratio (SNR) increases, the packet error rate (PER) does not improve. The STA may support up to MCS11 in response to a PPDU conforming to 80 MHz, which is the reception ability of the STA, but may not support MCS7, MCS9, and MCS11 due to the relatively high PER in response to a PPDU conforming to 160 MHz.

[0065] In other words, the MCS that the STA can support in the wider bandwidth may be limited to an MCS having a data rate lower than that of MCS7.

[0066] According to an embodiment, the STA may transmit performance information indicating the MCSs that can be supported in a wider bandwidth to the AP in consideration of the performance of the wider bandwidth. The AP may select an MCS from the performance information and apply the selected MSC to the PPDU allocated to the STA that performs operations to support the wider bandwidth.

[0067] FIG. 5A is an enhanced view showing an extremely high throughput (EHT) capability element format for transmitting performance information according to an embodiment. FIGS. 5B and 5C are views showing the 'EHT PHY Capability Information' field for transmitting performance information according to an embodiment.

[0068] Referring to FIG. 5A, the 'EHT Capability Element Format' may include an 'Element' field, a 'Length' field, an 'Element ID Extension' field, an 'EHT MAC Capability Information' field, an 'EHT PHY Capability Information' field, a 'Supported EHT-MCS and NSS Set' field, and an 'EHT PPE Threshold' field (optionally). The fields of the 'EHT Capability Element Format' are defined in IEEE P802.11be, and thus detailed descriptions other than those related to the concept of the present invention will be omitted.

[0069] According to an embodiment, the performance information of the STA in the wideband may be included in one of the 'EHT PHY Capability Information' field and the 'Supported EHT-MCS and NSS Set' field and may be transmitted to the AP. The number of bits included in the 'EHT PHY Capability Information' field and the number of bits included in the 'Supported EHT-MCS and NSS Set' field may vary depending on the representation scheme indicating the performance of the STA. In other embodiments, other fields of the 'EHT Capability Element Format' are used to transmit the performance information to the AP.

[0070] Further referring to FIG. 5B, the "EHT PHY Capability Information" field may include a "Reserved" sub-field, a "Support 320 MHz in 6 GHz" sub-field, a "Support 242 Tone RUs in BW wider than 20 MHz" sub-field, a "NDP with 4x EHT-LTF and 3.2 μs GI" sub-field, a "Partial Bandwidth UL MU-MIMO" sub-field, a "SU Beamformer" sub-field, a "SU Beamforming Receiver" sub-field, a "Beamforming Receiver SS (≤80 MHz)" sub-field, a "Beamforming Receiver SS (=160 MHz)" sub-field, a "Beamforming Receiver SS (=320 MHz)" sub-field, a "Number of探测 Dimensions (≤80 MHz)" sub-field, a "Number of探测 Dimensions (=160 MHz)" sub-field, a "Number of探测 Dimensions (=320 MHz)" sub-field, a "Ng = 16 SU Feedback" sub-field, a "Ng = 16 MU Feedback" sub-field, a "Codebook Size (φ, ψ) = {4, 2} SU Feedback" sub-field, a "Codebook Size (φ, ψ) = {7, 5} MU Feedback" sub-field, a "Trigger SU Beamforming Feedback" sub-field, a "Trigger MU Beamforming Partial Bandwidth Feedback" sub-field, a "Trigger CQI Feedback" sub-field, a "Partial Bandwidth DL MU-MIMO" sub-field, a "PSR-based SR Support" sub-field, a "Power Boost Factor Support" sub-field, an "EHT MU PPDU with 4x EHT-LTF and 3.8 μs GI" sub-field, a "Max Nc" sub-field, a "Non-Trigger CQI Feedback" sub-field, a "Tx 1024-QAM and 4096-QAM < 242 Tone RU Support" sub-field, a "Rx 1024-QAM and 4096-QAM < 242 Tone RU Support" sub-field, a "PPE Threshold Existence" sub-field, a "Generic Nominal Packet Padding" sub-field, a "Maximum Number of Supported EHT-LTFs" sub-field, a "Support MCS 15" sub-field, a "Support EHT DUP in 6 GHz" sub-field, a "Support 20 MHz Operating STA Receiving NDP with Wider Bandwidth" sub-field, a "Non-OFDMA UL MU-MIMO (BW ≤ 80 MHz)" sub-field, a "Non-OFDMA UL MU-MIMO (BW = 160 MHz)" sub-field, a "Non-OFDMA UL MU-MIMO (BW = 320 MHz)" sub-field, a "MU Beamformer (BW ≤ 80 MHz)" sub-field, a "MU Beamformer (BW = 160 MHz)" sub-field, a "MU Beamformer (BW = 320 MHz)" sub-field, and a "Wider BW Support" sub-field.

[0071] It should be noted that there is an unclear "探测" in the original text, which may need to be further clarified in the actual context. I translated it as "探测" for now.According to an embodiment, the 'wider BW support' sub-field may include performance information of the STA. The 'wider BW support' sub-field may include n bits, where the number n may be determined according to the number of bits of the performance information constituting the STA. As described above, the number of bits of the performance information constituting the STA may vary depending on the representation scheme indicating the performance of the STA.

[0072] According to an embodiment, the performance information of the STA included in the 'wider BW support' sub-field may include first performance information indicating a first MCS that the STA can support in a wider bandwidth, and / or second performance information indicating whether the STA can support a wider bandwidth.

[0073] Further referring to FIG. 5C, as illustrated in FIG. 5B, the 'wider BW support' sub-field for transmitting the performance information of the STA may not be defined separately, and the performance information of the STA rather than empty data may be included in a specific sub-field, and the specific sub-field may be filled with empty data according to the state, communication state, and the like of the STA and transmitted to the AP. For example, when the'support 242 subcarrier RUs in a BW wider than 20 MHz' sub-field is scheduled to be filled with empty data, the performance information of the STA rather than empty data may be transmitted to the AP. In other examples, the performance information of the STA is included in another sub-field and transmitted to the AP under specific circumstances.

[0074] An embodiment will now be mainly described in which the STA supports a wider bandwidth and transmits first performance information indicating a first MCS that can be supported in the wider bandwidth to the AP.

[0075] FIG. 6 is a flowchart of an operation method of an AP 410 (an example of any of the APs 101, 103, or 210) and an STA 420 (an example of any of the STAs 111 to 114, 220, 320, or 330) according to an embodiment.

[0076] In operation S110, the STA 420 may transmit first performance information for supporting a wider bandwidth to the AP 410, where the first performance information may indicate a first MCS that the STA 420 can support in the wider bandwidth. In operation S120, the AP 410 may select one of the first MCSs based on the first performance information. According to an embodiment, the AP 410 may select the first MCS having the highest data rate among the first MCSs. According to some embodiments, the AP 410 may select one of the first MCSs by further considering the channel state with the STA 420. The channel state may be estimated by the AP 410 based on the sounding reference signal received from the STA 420, or may be estimated by the STA 420 and reported as feedback to the AP 410. In operation S130, the AP 410 may generate a second PPDU allocated to the STA 420 based on the selected first MCS. In operation S140, the AP 410 may transmit a first PPDU including the second PPDU to the STA 420. A second bandwidth conforming to the first PPDU may be greater than a first bandwidth conforming to the second PPDU. Alternatively, the first bandwidth and the second bandwidth are equal.

[0077] FIG. 7A is a view showing first performance information according to an embodiment, and FIG. 7B is a view for explaining the performance of the STA indicated by the first performance information of FIG. 7A.

[0078] Referring to FIG. 7A, the first performance information may include 16 bits indicating whether each of MCS0 having an index 0 to MCS15 having an index 15 defined in IEEE P802.11be can be supported. For example, the value of the bit when the STA can support MCS0 may be set to '1'; and the value of the bit when the STA cannot support MCS0 may be set to '0'; or vice versa.

[0079] Further referring to FIG. 7B, the MCSs are configured in the direction of increasing data rate. Embodiments are described based on the assumption that the AP and the STA identify the MCSs based on the MCSs configured in the above direction. The modulation scheme and coding rate of MCS14 with index 14 may be BPSK-DCM-DUP and 1 / 2, the modulation scheme and coding rate of MCS15 with index 15 may be BPSK-DCM and 1 / 2, the modulation scheme and coding rate of MCS0 with index 0 may be BPSK and 1 / 2, the modulation scheme and coding rate of MCS1 with index 1 may be QPSK and 1 / 2, the modulation scheme and coding rate of MCS2 with index 2 may be quadrature phase shift keying (QPSK) and 3 / 4, the modulation scheme and coding rate of MCS3 with index 3 may be 16-QAM and 1 / 2, the modulation scheme and coding rate of MCS4 with index 4 may be 16-QAM and 3 / 4, the modulation scheme and coding rate of MCS5 with index 5 may be 64-QAM and 2 / 3, the modulation scheme and coding rate of MCS6 with index 6 may be 64-QAM and 3 / 4, the modulation scheme and coding rate of MCS7 with index 7 may be 64-QAM and 5 / 6, the modulation scheme and coding rate of MCS8 with index 8 may be 256-QAM and 3 / 4, the modulation scheme and coding rate of MCS9 with index 9 may be 256-QAM and 5 / 6, the modulation scheme and coding rate of MCS10 with index 10 may be 1024-QAM and 3 / 4, the modulation scheme and coding rate of MCS11 with index 11 may be 1024-QAM and 5 / 6, the modulation scheme and coding rate of MCS12 with index 12 may be 4096-QAM and 3 / 4, and the modulation scheme and coding rate of MCS13 with index 13 may be 4096-QAM and 5 / 6.

[0080] The AP may identify a first MCS among MCS0 to MCS15 that the STA can support in a wider bandwidth based on the first performance information.

[0081] It will be fully understood that in addition to the MCSs defined in FIG. 7B, other MCSs may be further defined, and the technical spirit of the inventive concept is applicable to other MCSs.

[0082] FIG. 8A is a view showing first performance information according to an embodiment, and FIG. 8B is a view for explaining the performance of the STA indicated by the first performance information of FIG. 8A.

[0083] Referring to FIG. 8A, the first performance information may include bits indicating whether each of the specific MCSs among MCS0 to MCS15 defined in IEEE P802.11be has a data rate equal to or greater than a reference value. For example, the specific MCSs may include MCS12 and MCS13. In this case, the first performance information may include two bits. According to an embodiment, the support possibility of the specific MCS indicated by the first performance information may be determined differently in advance, and the specific MCS may be pre-identified by the AP and the STA.

[0084] Further referring to FIG. 8B, the AP may identify whether the STA is capable of supporting each of MCS12 and MCS13 in a wider bandwidth based on the first performance information. The AP may identify that MCS0 to MCS11, MCS14, and MCS15, which have data rates lower than MCS12, can be supported by the STA in a wider bandwidth.

[0085] FIG. 9A is a view showing the first performance information according to an embodiment, and FIG. 9B is a view for explaining the performance of the STA indicated by the first performance information of FIG. 9A.

[0086] Referring to FIG. 9A, the first performance information may include bits indicating the specific MCS having the highest data rate among MCS0 to MCS15 defined in IEEE P802.11be. For example, the number of MCSs defined in IEEE P802.11be is 16, and the first performance information may include four bits such that the first performance information can indicate the specific MCS.

[0087] Further referring to FIG. 9B, when the specific MCS is MCS11, the AP may identify MCS0 to MCS11, MCS14, and MCS15, which have data rates less than or equal to the data rate of MCS11, as the first MCSs that the STA can support in a wider bandwidth based on the first performance information. In other words, the AP may identify that the STA cannot support MCS12 and MCS13 in a wider bandwidth based on the first performance information.

[0088] FIG. 10A is a view showing first performance information according to an embodiment, and FIG. 10B is a view for explaining the performance of the STA indicated by the first performance information of FIG. 10A. In FIG. 10A, when the STA receives a third PPDU with a third bandwidth that is less than or equal to the first bandwidth that can be supported during conventional protocol transmission and reception, it is assumed that information indicating the "second MCS" that the STA can support among MCS0 to MCS15 defined in IEEE P802.11be is transmitted to the AP via the "Supported EHT-MCS and NSS Set" field of FIG. 5A. For example, the information indicating the second MCS may be included in the "EHT-MCS Mapping (BW≤80 MHz, except for non-AP STAs with only 20 MHz)" sub-field of the "Supported EHT-MCS and NSS Set" field. For ease of explanation, the second MCS may be referred to as the MCS that the STA can support in the "normal bandwidth".

[0089] Referring to FIG. 10A, the first performance information may include relative MCS information. The relative MCS information may include at least one bit indicating an offset from a specific MCS having the highest data rate among the second MCSs. The first performance information may include the number of bits determined according to the range of the offset. For example, when the offset can have any value from 0 to 3, the first performance information may include two bits.

[0090] Further referring to FIG. 10B, when the offset is 2 and the second MCS having the highest data rate among the second MCSs that the STA can support in the normal bandwidth is MCS12, the AP may identify MCS0 to MCS10, MCS14, and MCS15 having a data rate less than or equal to the data rate of MCS10, which is 2 less than MCS12, as the first MCS that the STA can support in the wider bandwidth based on the first performance information.

[0091] FIGS. 11A to 11C are views showing first performance information according to an embodiment. In FIG. 11A, as described above, it is assumed as an example that the STA can support a first bandwidth of up to 80 MHz and the second bandwidth greater than the first bandwidth can be 160 MHz or 320 MHz. The descriptions of FIGS. 11A to 11C that are the same as those given above with reference to FIG. 10A will now be omitted.

[0092] Referring to FIG. 11A, the first performance information may include information indicating a first MCS corresponding to values that the second bandwidth may have in the wider bandwidth. For example, the first performance information may include information indicating the first MCS that the STA can support in the wider bandwidth when the second bandwidth is 160 MHz, and information indicating the first MCS that the STA can support in the wider bandwidth when the second bandwidth is 320 MHz.

[0093] According to an embodiment, the AP may finely select an MCS for generating a PPDU allocated to the STA based on the first performance information considering the performance of the STA segmented according to the value of the second bandwidth.

[0094] Referring further to FIG. 11B, the first performance information may include information indicating an offset of an MCS conforming to 1024-QAM in the normal bandwidth and information indicating an offset of an MCS conforming to 4096-QAM in the normal bandwidth.

[0095] According to an embodiment, the AP may finely select an MCS for generating a PPDU allocated to the STA based on the first performance information considering the performance of the STA segmented for each MCS.

[0096] Referring further to FIG. 11C, the first performance information may include information indicating an offset of an MCS conforming to 1024-QAM in the normal bandwidth and information indicating an offset of an MCS conforming to 4096-QAM in the normal bandwidth when the second bandwidth is 160 MHz, and may include information indicating an offset of an MCS conforming to 1024-QAM in the normal bandwidth and information indicating an offset of an MCS conforming to 4096-QAM in the normal bandwidth when the second bandwidth is 320 MHz.

[0097] FIG. 12 is a flowchart of an embodiment of operation S120 in FIG. 6.

[0098] Referring to FIG. 12, in operation S121a after operation S110 in FIG. 6, the AP 410 may apply the first performance information to information related to the maximum number of spatial streams of each MCS. In operation S122a, the AP 410 may identify the first MCS that the STA 420 can support in the wider bandwidth based on the result of operation S121a. In operation S123a, the AP 410 may select one of the first MCSs to generate a PPDU allocated to the STA 420. A detailed description of the embodiment of FIG. 12 is provided with reference to FIGS. 13A to 13C.

[0099] FIG. 13A is a view showing the "Supported EHT-MCS and NSS Set" field for transmitting first performance information according to an embodiment; FIGS. 13B and 13C are views for explaining the performance of the STA indicated by the first performance information.

[0100] Referring to FIG. 13A, the "Supported EHT-MCS and NSS Set" field may include an "EHT-MCS Mapping (only 20 MHz non-AP STA)" sub-field, an "EHT-MCS Mapping (BW≤80 MHz, except only 20 MHz non-AP STA)" sub-field, an "EHT-MCS Mapping (BW = 160 MHz)" sub-field, and an "EHT-MCS Mapping (BW = 320 MHz)" sub-field. The "Supported EHT-MCS and NSS Set" field is defined in IEEE P802.11be, and thus detailed descriptions other than those related to the inventive concept will be omitted.

[0101] The "EHT-MCS Mapping (BW≤80 MHz, except only 20 MHz non-AP STA)" sub-field may include information related to the maximum number of spatial streams for each MCS in FIG. 12.

[0102] The "EHT-MCS Mapping (BW≤80 MHz, except only 20 MHz non-AP STA)" sub-field may include a "Rx Max Nss for Supported EHT-MCS 0-9" sub-field, a "Tx Max Nss for Supported EHT-MCS 0-9" sub-field, a "Rx Max Nss for Supported EHT-MCS 10-11" sub-field, a "Tx Max Nss for Supported EHT-MCS 10-11" sub-field, a "Rx Max Nss for Supported EHT-MCS 12-13" sub-field, and a "Tx Max Nss for Supported EHT-MCS 12-13" sub-field. Nss or NSS may refer to the number of spatial streams.

[0103] Specifically, the information related to the maximum number of spatial streams for each MCS in FIG. 12 may be included in the "Rx Max Nss for Supported EHT-MCS 0-9" sub-field, the "Rx Max Nss for Supported EHT-MCS 10-11" sub-field, and the "Rx Max Nss for Supported EHT-MCS 12-13" sub-field.

[0104] The subfield of "Rx Max Nss supporting EHT-MCS 0-9" can indicate the maximum number of spatial streams that the STA can support within MCS0 to MCS9. The subfield of "Rx Max Nss supporting EHT-MCS 10-11" can indicate the maximum number of spatial streams that the STA can support within MCS10 and MCS11. And the subfield of "Rx Max Nss supporting EHT-MCS 12-13" can indicate the maximum number of spatial streams that the STA can support within MCS12 and MCS13. Although MCS14 and MCS15 are not shown in Figure 13A, MCS14 and MCS15 can be processed according to MCS0 to MCS9.

[0105] Referring further to Figure 13B, the value of the subfield can indicate the maximum number of spatial streams. For example, the subfield of "Rx Max Nss supporting EHT-MCS 0-9", the subfield of "Rx Max Nss supporting EHT-MCS 10-11", and the subfield of "Rx Max Nss supporting EHT-MCS 12-13" can have values from 0 to 15. When the value of the subfield is 0, it indicates that spatial multiplexing is not supported. And when the value of the subfield is each of 1 to 8, it indicates that the maximum number of spatial streams that can be supported is each of 1 to 8. The maximum number of spatial streams corresponding to subfield values from 9 to 15 can be in a "reserved" state.

[0106] In Figure 13C, it is assumed that the subfield of "Rx Max Nss supporting EHT-MCS 0-9", the subfield of "Rx Max Nss supporting EHT-MCS 10-11", and the subfield of "Rx Max Nss supporting EHT-MCS 12-13" have values 4, 2, and 1 respectively, and the offset of the first performance information conforming to Figure 10A is 1. In other words, when supporting MCS0 to MCS9 in the normal bandwidth, the STA can support four maximum spatial streams. When supporting MCS10 and MCS11 in the normal bandwidth, the STA can support two maximum spatial streams. And when supporting MCS11 and MCS12 in the normal bandwidth, the STA can support one maximum spatial stream. MCS0 to MCS9 can be referred to as being included in the first MCS group, MCS10 and MCS11 can be referred to as being included in the second MCS group, and MCS12 and MCS13 can be referred to as being included in the third MCS group.

[0107] Referring to Figure 13C, the first performance information can indicate the offset of a specific MCS with the highest data rate from at least one of the first MCS group to the third MCS group.

[0108] In the first scenario, the AP can identify the first MCS that the STA can support in a wider bandwidth by applying the first performance information to the first MCS group to the third MCS group. In other words, the AP can identify MCS0 to MCS8 with data rates less than or equal to the data rate of MCS8 that is one interval away from MCS9 with the highest data rate in the first MCS group, MCS10 that is one interval away from MCS11 with the highest data rate in the second MCS group, and MCS12 that is one interval away from MCS13 with the highest data rate in the third MCS group as the first MCS.

[0109] In the second scenario, the AP can identify the first MCS by selectively applying the first performance information to the first MCS group that supports the largest number (i.e., four) of maximum spatial streams among the first MCS group to the third MCS group. In other words, the AP can identify MCS0 to MCS8 and MCS10 to MCS13 with data rates less than or equal to the data rate of MCS8 that is one interval away from MCS9 with the highest data rate in the first MCS group as the first MCS.

[0110] In the third scenario, the AP can identify the first MCS by selectively applying the first performance information to the third MCS group that includes the MCS with the highest data rate among the first MCS group to the third MCS group. In other words, the AP can identify MCS12 that is one interval away from MCS13 with the highest data rate in the third MCS group and MCS0 to MCS11 as the first MCS.

[0111] In the fourth scenario, the AP can identify the first MCS by selectively applying the first performance information to the second MCS group and the third MCS group that include the MCS with a data rate equal to or greater than the reference value among the first MCS group to the third MCS group. In other words, the AP can identify MCS10 that is one interval away from MCS11 with the highest data rate in the second MCS group, MCS12 that is one interval away from MCS13 with the highest data rate in the third MCS group, and MCS0 to MCS9 as the first MCS.

[0112] In other embodiments, the AP identifies the first MCS that the STA can support in a wider bandwidth by applying the first performance information to at least one of the first MCS group to the third MCS group in various ways.

[0113] FIG. 14 is a view showing the "Supported EHT-MCS and NSS Set" field for transmitting first performance information according to an embodiment.

[0114] With further reference to FIG. 14, the first performance information may be included in at least one of the "EHT-MCS Mapping (BW = 160 MHz)" sub-field and the "EHT-MCS Mapping (BW = 320 MHz)" sub-field and may be transmitted to the AP. In other words, at least one of the "EHT-MCS Mapping (BW = 160 MHz)" sub-field and the "EHT-MCS Mapping (BW = 320 MHz)" sub-field may be used to transmit the first performance information to the AP.

[0115] When the STA supports a first bandwidth of 80 MHz or less than 80 MHz, the "EHT-MCS Mapping (BW = 160 MHz)" sub-field and the "EHT-MCS Mapping (BW = 320 MHz)" sub-field may be filled with empty data. Therefore, according to an embodiment, the first performance information rather than the empty data may be included in one of the "EHT-MCS Mapping (BW = 160 MHz)" sub-field and the "EHT-MCS Mapping (BW = 320 MHz)" sub-field and may be transmitted to the AP.

[0116] According to an embodiment, the first performance information configured in the same or similar manner as the method described above with reference to FIG. 11A may be included in the "EHT-MCS Mapping (BW = 160 MHz)" sub-field and the "EHT-MCS Mapping (BW = 320 MHz)" sub-field and may be transmitted to the AP. Specifically, the information configured with the B63_1 bit and the B63_2 bit in FIG. 11A may be included in the "EHT-MCS Mapping (BW = 160 MHz)" sub-field, and the information configured with the B63_3 bit and the B63_4 bit in FIG. 11A may be included in the "EHT-MCS Mapping (BW = 320 MHz)" sub-field.

[0117] FIG. 15 is a flowchart of an embodiment of operation S120 in FIG. 6.

[0118] Referring to FIG. 15, in operation S121b after operation S110 of FIG. 6, AP 410 may apply the first performance information to the information related to the minimum required adjacent channel rejection level. In operation S122b, AP 410 may identify the first MCS that STA 420 can support in a wider bandwidth based on the result of operation S121b. In operation S123b, AP 410 may select one of the first MCSs to generate a PPDU allocated to STA 420. A detailed description of the embodiment of FIG. 15 is provided with reference to FIGS. 16A and 16B.

[0119] FIG. 16A is a view showing the first performance information according to an embodiment, and FIG. 16B is a view for explaining the performance of the STA indicated by the first performance information of FIG. 16A.

[0120] Referring to FIG. 16A, the first performance information may include information indicating the adjacent channel interference (ACI) rejection performance of the STA. The ACI rejection performance may be associated with the information related to the minimum required adjacent channel rejection level defined in IEEE P802.11be. The ACI rejection performance may be information indicating the rejection level additionally supported by the STA according to the performance of the STA.

[0121] Further referring to FIG. 16B, the minimum required adjacent channel rejection level and the non-adjacent channel rejection level may be determined for each of MCS0 to MCS15, and the AP may perform operations under the assumption that the STA can support the minimum required adjacent channel rejection level and the adjacent channel rejection levels corresponding to each of MCS0 to MCS15. In this case, the STA may transmit the first performance information indicating the ACI rejection performance to the AP so that the AP can perform operations according to the performance of the STA.

[0122] For example, when the adjacent channel rejection level measured by the STA is -9 (dB) and the ACI rejection performance of the STA is -5 (dB), the AP may determine that the final adjacent channel rejection level of the STA is -14 (dB) to thereby identify the first MCS that the STA can support in a wider bandwidth. In other words, the AP may identify MCS0 to MCS11, MCS 14, and MCS 15 as the first MCS.

[0123] FIG. 17 is a flowchart of an operating method of an AP according to an embodiment.

[0124] Referring to FIG. 17, in operation S200, the AP can check the bandwidth of the STA. In operation S210, the AP can determine whether the STA supports wide bandwidth. Specifically, the AP can receive second performance information indicating whether the STA supports wide bandwidth from the STA, and can determine whether the STA supports wide bandwidth based on the second performance information. When the result of operation S210 is "yes", in operation S220, the AP can schedule the second PPDU allocated to the STA by using the remaining RUs except for the boundary RUs within the supportable bandwidth of the STA. When the result of operation S210 is "no", in operation S230, the AP can schedule the second PPDU by using the RUs within the supportable bandwidth of the STA. In operation S240, the AP can include the second PPDU and can transmit the first PPDU conforming to the second bandwidth.

[0125] FIGS. 18A and 18B are views for explaining a method of scheduling the second PPDU allocated to the STA supporting a wider bandwidth of the AP according to an embodiment. In FIGS. 18A and 18B, it is assumed that the first bandwidth supportable by the STA is 80 MHz.

[0126] Referring to FIG. 18A, the AP can schedule the second PPDU allocated to the STA such that when the second PPDU allocated to the STA is included in the first PPDU conforming to the second bandwidth of 160 MHz, the RUs located at the boundary of the band having a bandwidth of 80 MHz are not allocated to the STA. In other words, when the AP transmits the second PPDU allocated to the STA, the RUs located at the boundary of the band having a bandwidth of 80 MHz may not be used. For example, in the first PPDU conforming to the second bandwidth of 160 MHz, the AP can perform scheduling such that RU1, RU37, RU38, and RU74 among the RUs having an RU size corresponding to 26-tone RUs are not allocated to the STA. As another example, in the first PPDU conforming to the second bandwidth of 160 MHz, the AP can perform scheduling such that RU1, RU16, RU17, and RU32 among the RUs having an RU size corresponding to 52-tone RUs are not allocated to the STA. As another example, in the first PPDU conforming to the second bandwidth of 160 MHz, the AP can perform scheduling such that MRU1, MRU8, MRU9, and MRU16 among the MRUs having an MRU size corresponding to (106 + 26)-tone multiple RUs (MRUs) are not allocated to the STA. As another example, in the first PPDU conforming to the second bandwidth of 160 MHz, the AP can perform scheduling such that MRU4, MRU5, MRU6, and MRU7 among the MRUs having an MRU size corresponding to (484 + 242)-tone MRUs are not allocated to the STA.

[0127] Referring further to FIG. 18B, the AP may schedule the second PPDU to be allocated to the STA such that when the second PPDU allocated to the STA is included in the first PPDU with a second bandwidth conforming to 320 MHz, the RUs located at the boundary of the band with a bandwidth of 80 MHz are not allocated to the STA. For example, in the first PPDU with a second bandwidth conforming to 320 MHz, the AP may perform scheduling such that RU1, RU37, RU38, RU74, RU75, RU111, RU112, and RU148 in the RUs with an RU size corresponding to a 26-tone RU are not allocated to the STA. As another example, in the first PPDU with a second bandwidth conforming to 320 MHz, the AP may perform scheduling such that RU1, RU16, RU17, RU32, RU33, RU48, RU49, and RU64 in the RUs with an RU size corresponding to a 52-tone RU are not allocated to the STA. As another example, in the first PPDU with a second bandwidth conforming to 320 MHz, the AP may perform scheduling such that MRU1, MRU8, MRU9, MRU16, MRU17, MRU24, MRU25, and MRU32 in the MRUs with an MRU size corresponding to a (106 + 26)-tone MRU are not allocated to the STA. As another example, in the first PPDU with a second bandwidth conforming to 320 MHz, the AP may perform scheduling such that MRU2, MRU3, MRU4, MRU5, MRU6, MRU7, MRU10, MRU11, MRU12, MRU13, MRU14, and MRU15 in the MRUs with an MRU size corresponding to a (484 + 242)-tone MRU are not allocated to the STA.

[0128] In FIGS. 18A and 18B, the RUs excluded from allocation to the STA may vary depending on the type of RUs constituting the second PPDU.

[0129] FIG. 19 is a conceptual diagram of an Internet of Things (IoT) network system 1000 of an application embodiment.

[0130] Referring to FIG. 14, the IoT network system 1000 may include multiple IoT devices, an AP 1200, a gateway 1250, a wireless network 1300, and a server 1400. IoT may refer to a network in things using wired / wireless communication.

[0131] IoT devices can be grouped according to their characteristics. For example, IoT devices can be divided into groups of home gadgets 1100, home appliances / furniture 1120, entertainment devices 1140, and vehicles 1160. Multiple IoT devices (e.g., groups of home gadgets 1100, home appliances / furniture 1120, and entertainment devices 1140) can be connected to a communication network or another IoT device via the AP 1200. The AP 1200 can be embedded in an IoT device. The gateway 1250 can change the protocol to allow the AP 1200 to access an external wireless network. IoT devices (e.g., groups of home gadgets 1100, home appliances / furniture 1120, and entertainment devices 1140) can be connected to an external communication network via the gateway 1250. The wireless network 1300 can include the Internet and / or a public network. Multiple IoT devices (e.g., groups of home gadgets 1100, home appliances / furniture 1120, entertainment devices 1140, and vehicles 1160) can be connected to a server 1400 that provides specific services via the wireless network 1300, and a user can use the services via at least one of the IoT devices (e.g., groups of home gadgets 1100, home electrical equipment / furniture 1120, entertainment devices 1140, and vehicles 1160).

[0132] According to an embodiment, multiple IoT devices (e.g., groups of home gadgets 1100, home appliances / furniture 1120, entertainment devices 1140, and vehicles 1160) can transmit and receive multiple pieces of performance information to and from each other in a relatively wide bandwidth, and can demodulate and transmit / receive signals based on the multiple pieces of performance information. Therefore, the IoT devices (e.g., groups of home gadgets 1100, home appliances / furniture 1120, entertainment devices 1140, and vehicles 1160) can provide high-quality services to users by performing efficient and effective communication.

[0133] In the embodiments described above, the hardware access method has been described as an example. However, other embodiments include software-based access methods. In addition, the various functions described above can be implemented or supported by artificial intelligence technologies or one or more computer programs, where each of the programs is formed of computer-readable program code and executed in a computer-readable recording medium. "Application program" and "program" refer to one or more computer programs, software components, instruction sets, procedures, functions, objects, classes, scenarios, related data, or portions thereof that are suitable for implementing multiple segments of computer-readable program code. "Computer-readable program code" includes all types of computer program code, including source code, object code, and executable code. "Computer-readable medium" includes all types of media that can be accessed by a computer, such as read only memory (ROM), random access memory (RAM), hard disk drive, compact disk (CD), digital video disk (DVD), and other types of memory. "Non-transitory" computer-readable media excludes wired, wireless, optical, or other communication links that transmit transient electrical signals or other signals. Non-transitory computer-readable media includes media in which data can be permanently stored and media in which data can be stored and rewritten later, such as rewritable optical disks or erasable memory devices.

[0134] Although the inventive concept has been specifically illustrated and described with reference to its embodiments, it should be understood that various changes in form and detail can be made therein without departing from the spirit and scope of the following claims.

[0135] 100, 200, 300: Wireless communication system 101, 103, 210, 310, 410, 1200: Access Point (AP) 111, 112, 113, 114, 220, 320, 330, 420: Station (STA) 120, 125: Coverage area 130: Network 211, 221: Antenna 212, 222: Transceiver 213, 223: Processing circuitry 214, 224: Performance information 1000: Internet of Things (IoT) network system 1100: Home gadget 1120: Household appliances / furniture 1140: Entertainment equipment 1160: Vehicle 1250: Gateway 1300: Wireless network 1400: Server BW1: First bandwidth BW2: Second bandwidth CH1: First channel CH2: Second channel S110, S120, S121a, S121b, S122a, S122b, S123a, S123b, S130, S140, S200, S210, S220, S230, S240: Operations

Claims

1. A base station (STA) communicating with an access point (AP) in a wireless local area network (WLAN) system, the base station comprising: A transceiver configured to support the transmission and reception of signals within at least a first bandwidth; The processing circuitry is configured to support the wider bandwidth by obtaining at least one resource unit corresponding to the first bandwidth from a Physical Layer Protocol Data Unit (PPDU) conforming to a bandwidth wider than the first bandwidth, wherein the processing circuitry is configured to control the transceiver to transmit a signal containing a capability information field to the access point, and wherein the capability information field includes: a first performance information subfield indicating whether a first modulation scheme is supported in the wider bandwidth according to the capabilities of the base station; And a second performance information subfield, indicating whether a second modulation scheme is supported in the wider bandwidth based on the capabilities of the base station.

2. The base station as claimed in claim 1, wherein the data mapped to the at least one resource unit corresponding to the first bandwidth is modulated according to the first modulation scheme or the second modulation scheme.

3. The base station as claimed in claim 1, wherein the first modulation scheme corresponds to one of 16-quadrature amplitude modulation (QAM), 64-QAM, 256-QAM, 1024-QAM, and 4096-QAM, and wherein the second modulation scheme corresponds to a different one of 16-QAM, 64-QAM, 256-QAM, 1024-QAM, and 4096-QAM.

4. The base station as claimed in claim 1, wherein the capability of the base station is related to the sharpness of the down-frequency filter used by the processing circuitry system when acquiring the at least one resource unit.

5. The base station as claimed in claim 1, wherein the signal further indicates information on whether the wider bandwidth is supported.

6. The base station as claimed in claim 1, wherein the first performance information subfield includes bits indicating whether the first modulation scheme is supported.

7. The base station as claimed in claim 1, wherein the second performance information subfield includes bits indicating whether the second modulation scheme is supported.

8. An access point (AP) for communicating with a base station (STA), said base station supporting transmission and reception within at least a first bandwidth defined by a conventional wireless local area network protocol in a wireless local area network system, said access point comprising: A transceiver, configured to receive from the base station a signal including capability information fields, wherein the capability information fields include: a first performance information subfield indicating whether the base station supports a first modulation scheme among multiple modulation schemes in a wider bandwidth than the first bandwidth, based on the base station's capabilities; and a second performance information subfield indicating whether the base station supports a second modulation scheme in the wider bandwidth, based on the base station's capabilities, and the transceiver is configured to transmit physical packet data units (PPDUs) to the base station; and a processing circuitry configured to select one modulation scheme from the first and second modulation schemes based on the signal and the channel state of the base station.

9. The access point as described in claim 8, wherein the capability of the base station is related to the sharpness of the down-frequency filter included in the base station.

10. The access point as described in claim 8, wherein the signal further indicates information on whether the wider bandwidth is supported.

11. The access point as described in claim 8, wherein the first performance information subfield includes bits indicating whether the first modulation scheme is supported.

12. The access point as described in claim 8, wherein the second performance information subfield includes bits indicating whether the second modulation scheme is supported.

13. The access point as claimed in claim 8, wherein the first modulation scheme corresponds to one of 16-quadrature amplitude modulation (QAM), 64-QAM, 256-QAM, 1024-QAM, and 4096-QAM, and wherein the second modulation scheme corresponds to a different one of 16-QAM, 64-QAM, 256-QAM, 1024-QAM, and 4096-QAM.

14. A method of operating a base station (STA) for communicating with an access point (AP) in a wireless local area network (WLAN) system, the method comprising: The system transmits a signal containing capability information fields to the access point, wherein the capability information fields include: a first performance information subfield indicating whether the base station supports a first modulation scheme in a wider bandwidth than a first bandwidth, based on the base station's capabilities; and a second performance information subfield indicating whether the base station supports a second modulation scheme in the wider bandwidth, based on the base station's capabilities; and receives physical packet data units (PPDUs) conforming to the wider bandwidth from the access point, wherein in the physical packet data units, data allocated to the base station corresponding to the first bandwidth is modulated according to either the first modulation scheme or the second modulation scheme.

15. The method of operation as described in claim 14 further includes obtaining the data, wherein obtaining the data includes sampling, filtering, and downsampling the physical packet data unit by using at least one sampling rate determined based on the ratio between the first bandwidth and the wider bandwidth and at least one downsampling filter.

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