Communication method and apparatus based on physical layer protocol data unit

Abstract

A communication method and apparatus based on PPDU are disclosed. This application is applicable to a wireless local area network system that supports 802.11 series protocols such as the next-generation Wi-Fi protocol of IEEE802.11ax, for example, 802.11be, Wi-Fi 7 or EHT, and the next-generation Wi-Fi protocol of 802.11be or Wi-Fi 8, and may be further applicable to a UWB-based wireless personal area network system, a sensing system, etc. The method includes the following. The transmitting end generates a PPDU and transmits the PPDU. Correspondingly, the receiving end receives the PPDU and processes the PPDU. The PPDU may include an L-STF, an L-LTF, an L-SIG field, and a first STF. The first STF is obtained based on a second STF and a first sequence, and the time length of the first STF is greater than the time length of the L-STF. The transmission distance of the PPDU can be effectively increased.

Description

Technical Field

[0001] [Cross - Reference to Related Applications] This application claims priority to Chinese Patent Application No. 202210509427.9, titled "COMMUNICATION METHOD BASED ON PHYSICAL LAYER PROTOCOL DATA UNIT AND APPARATUS", filed with the China National Intellectual Property Administration on May 11, 2022, and incorporates its entire content by reference.

[0002] [Technical Field] This application relates to the field of communication technologies, and in particular, to a communication method and apparatus based on a physical layer (PHY) protocol data unit (PPDU).

Background Art

[0003] Wi-Fi technology is a wireless local area network technology created by the Wi-Fi Alliance in the Institute of Electrical and Electronics Engineers (IEEE) 802.11 protocol. Wi-Fi technology generally includes two types of devices, namely, an access point (AP) and a station (STA). An AP may also be called a wireless access point, which is a provider of a Wi-Fi network, enables access by other wireless devices, and provides data access to the accessed devices. A device accessing a Wi-Fi network may be called an STA. For example, all electronic devices supporting Wi-Fi functions, such as mobile phones, tablet computers, and laptop computers, may be used as STAs.

[0004] User data transmission between the AP and the STA is executed via the PPDU. Currently, in the sixth generation of Wi-Fi protocols (801.11, 802.11b, 802.11a / g, 802.11n, 802.11ac, 802.11ax, etc.) that have been developed and are in widespread use, each generation of the IEEE 802.11 protocol has significantly improved communication quality and speed. For example, through PPDU transmission between the AP and the STA, the receiving end may execute PPDU detection, channel estimation, time synchronization, frequency synchronization, etc.

[0005] However, the transmission distance of the PPDU can be further extended.

Summary of the Invention

[0006] This application provides a PPDU-based communication method and apparatus for increasing the transmission distance of the PPDU.

[0007] According to a first aspect, an embodiment of this application provides a PPDU-based communication method. The method may be applied to a transmitting end, and the method includes the step of generating a PPDU, where the PPDU includes a legacy short training field (L-STF), a legacy long training field (L-LTF), a legacy signal (L-SIG) field, and a first STF. The first STF is obtained based on a second STF and a first sequence, and the time length of the first STF is greater than the time length of the L-STF, and the step of transmitting the PPDU.

[0008] According to a second aspect, an embodiment of this application provides a communication method based on a PPDU. The method may be applied to a receiving end. The method includes the step of receiving a PPDU, where the PPDU includes a legacy short training field L-STF, a legacy long training field L-LTF, a legacy signal L-SIG field, and a first STF. The first STF is obtained based on a second STF and a first sequence, and the time length of the first STF is greater than the time length of the L-STF. The method further includes the step of processing the PPDU.

[0009] In the PPDU provided in the embodiment of this application, the first STF is obtained by extending the second STF by using a first sequence, so that the time length of the first STF is greater than the time length of the L-STF. The above extension method may be considered as weighted repetition of signals in the time domain. Therefore, when the receiving end executes related processing based on the first STF, the equivalent signal-to-noise ratio can be increased (since the signal energy is constant and the noise is random, after superposition is performed on the first STF, the signal energy can be accumulated, but the noise cannot be accumulated. Therefore, the equivalent SNR increases). This ensures that the receiving end can detect the PPDU in a longer range. Furthermore, the PPDU provided in the embodiment of this application can realize long-distance transmission, increase the transmission distance of the PPDU, and increase the coverage area of the Wi-Fi signal.

[0010] Referring to the second aspect, in a possible implementation manner, the step of processing the PPDU includes at least one of the following steps: performing cross-correlation or auto-correlation on the first STF; and performing maximum likelihood synthesis on at least one of the first LTF, the first SIG field, and the first data field.

[0011] In this embodiment of this application, the receiving end may perform cross-correlation or auto-correlation on the first STF in more STF periods to increase the equivalent signal-to-noise ratio (SNR). Performing maximum likelihood synthesis on the first LTF, the first SIG field, and the first data field can increase the equivalent signal-to-noise ratio for channel estimation.

[0012] Referring to the first aspect or the second aspect, in a possible implementation manner, the acquisition of the first STF based on the second STF and the first sequence includes the following. The first STF is acquired based on the L-STF and the first sequence, or the first STF is acquired based on the ultra-high throughput EHT-STF and the first sequence, or the first STF is acquired based on the high efficiency HE-STF and the first sequence.

[0013] Referring to the first aspect or the second aspect, in a possible implementation manner, the acquisition of the first STF based on the L-STF and the first sequence includes the following. The first STF is acquired by extending the orthogonal frequency division multiplexing (OFDM) symbols in the L-STF by using the first sequence, or the first STF is acquired by extending a part of the OFDM symbols in the L-STF by using the first sequence.

[0014] In this embodiment of the present application, based on the first sequence, expanding an OFDM symbol or a part of an OFDM symbol in the second STF modulated through OFDM may be considered as weighted repetition of signals in the time domain. Therefore, the receiving end can increase the equivalent signal-to-noise ratio by using the expanded first STF and detect the PPDU in a longer range. The first STF in this application is expanded based on an OFDM symbol (or a part of an OFDM symbol), so that the advantages of OFDM modulation can be retained. For example, OFDM modulation can withstand frequency-selective fading and help improve the interference prevention ability of Wi-Fi signals. Furthermore, the existing design can be retained. For example, methods such as OFDM modulation-based coding, OFDM modulation-based interleaving, and OFDM modulation-based frequency domain repetition can still be retained.

[0015] It should be noted that the OFDM symbol in the L-STF shown in the embodiment of this application may also be referred to as the OFDM symbol occupied by the L-STF.

[0016] Referring to the first aspect or the second aspect, in a possible implementation, the PPDU further includes a first LTF, the first LTF is obtained based on the second LTF and the second sequence, and the time length of the first LTF is greater than the time length of the L-LTF.

[0017] In this embodiment of the present application, based on the second sequence, expanding an OFDM symbol or a part of an OFDM symbol in the second LTF modulated through OFDM may be considered as weighted repetition of signals in the time domain. Therefore, the receiving end can increase the equivalent signal-to-noise ratio by using the expanded first LTF and detect the PPDU in a longer range.

[0018] Referring to the first or second aspect, in a possible implementation, the acquisition of the first LTF based on the second LTF and the second sequence includes the following. The first LTF is acquired based on the L-LTF and the second sequence, or the first LTF is acquired based on the extremely high throughput (EHT)-LTF and the second sequence, or the first LTF is acquired based on the high efficient (HE)-LTF and the second sequence.

[0019] Referring to the first or second aspect, in a possible implementation, the acquisition of the first LTF based on the second LTF and the second sequence includes the following. The first LTF is acquired by extending the OFDM symbols in the second LTF by using the second sequence, or the first LTF is acquired by extending a part of the OFDM symbols in the second LTF by using the second sequence.

[0020] In this embodiment of this application, the second LTF is extended based on the OFDM symbols (or a part of the OFDM symbols) to obtain the first LTF. The advantages of OFDM modulation can be retained. For example, OFDM modulation can withstand frequency-selective fading and help improve the interference prevention ability of Wi-Fi signals. Furthermore, the existing design can be retained. For example, methods such as OFDM modulation-based coding, OFDM modulation-based interleaving, and OFDM modulation-based frequency domain repetition can still be retained.

[0021] It should be noted that the OFDM symbols in the second LTF shown in the embodiment of this application may also be referred to as the OFDM symbols occupied by the second LTF.

[0022] Referring to the first or second aspect, in a possible implementation, the PPDU further includes a first SIG field, the time duration of the first SIG field is greater than the time duration of the L-SIG field, and the first SIG field is obtained based on a fourth sequence and an OFDM symbol generated based on at least one of the following information, namely, service set color, association identifier, cyclic redundancy check, tail bit, and modulation and coding scheme.

[0023] Referring to the first or second aspect, in a possible implementation, the PPDU further includes a first data field, and the first data field is obtained based on a fifth sequence and an OFDM symbol generated based on information bits.

[0024] Referring to the first or second aspect, in a possible implementation, the first sequence is obtained based on a Barker code, and / or the second sequence is obtained based on a Barker code.

[0025] Referring to the first or second aspect, in a possible implementation, the fourth sequence is obtained based on a Barker code.

[0026] Referring to the first or second aspect, in a possible implementation, the fifth sequence is obtained based on a Barker code.

[0027] In this embodiment of this application, the good correlation characteristics (such as autocorrelation characteristics or cross-correlation characteristics) of the Barker code can help the receiving end accurately detect the PPDU. It should be understood that the process of identifying the PPDU is to distinguish whether the PPDU is received or noise is received through correlation. Therefore, the correlation value of the PPDU is high and the correlation value of the noise is low, so as to effectively improve the accuracy of detecting the PPDU.

[0028] Referring to the first or second aspect, in a possible implementation, the PPDU further includes a first binary phase shift keying (BPSK) mark field and a second BPSK mark field, and the first BPSK mark field or the second BPSK mark field is the same as the L-SIG field, or the first BPSK mark field or the second BPSK mark field is obtained based on the L-SIG field and a third sequence.

[0029] Referring to the first or second aspect, in a possible implementation, the elements in the third sequence include -1 and +1.

[0030] Referring to the first or second aspect, in a possible implementation, the PPDU further includes at least one of a repeated legacy signal (RL-SIG) field or a universal signal (U-SIG) field.

[0031] Referring to the first or second aspect, in a possible implementation, the U-SIG field includes at least one of the following information, that is, the physical layer version of the PPDU and the format of the PPDU, the version number of the physical layer version of the PPDU is greater than 0, and the format of the PPDU indicates that the format of the PPDU is an extended range PPDU format.

[0032] Referring to the first or second aspect, in a possible implementation, the L-STF, L-LTF, and L-SIG fields are included in the first part of the PPDU, the first STF, the first LTF, and the first SIG fields are included in the second part of the PPDU, and the bandwidth of the first part is greater than the bandwidth of the second part.

[0033] In this embodiment of this application, the bandwidth of the first part is larger than the bandwidth of the second part. Therefore, when the power spectral density is not limited, by reducing the transmission bandwidth of the second part of the PPDU and increasing the power spectral density, the transmission distance of the second part can be effectively increased, thereby increasing the coverage area of the Wi-Fi signal.

[0034] According to a third aspect, an embodiment of this application provides a communication device configured to execute the method in any one of the first aspect or possible implementation manners of the first aspect. The communication device includes a unit configured to execute the method in any one of the first aspect or possible implementation manners of the first aspect.

[0035] According to a fourth aspect, an embodiment of this application provides a communication device configured to execute the method in any one of the second aspect or possible implementation manners of the second aspect. The communication device includes a unit configured to execute the method in any one of the second aspect or possible implementation manners of the second aspect.

[0036] In one example, in the third aspect or the fourth aspect, the communication device may include a transceiver unit and a processing unit. For specific descriptions of the transceiver unit and the processing unit, refer to the device embodiments shown below.

[0037] In another example, in the third aspect, the communication device may include a generating unit and a transmitting unit. In the fourth aspect, the communication device may include a receiving unit and a processing unit. For specific descriptions of the units, refer to the device embodiments shown below.

[0038] According to a fifth aspect, an embodiment of this application provides a communication device. The communication device includes a processor configured to execute the method shown in any one of the first aspect or possible implementation manners of the first aspect. Alternatively, the processor is configured to execute a program stored in a memory. When the program is executed, the method shown in any one of the first aspect or possible implementation manners of the first aspect is executed.

[0039] In a possible implementation manner, the memory is located outside the communication device.

[0040] In a possible implementation manner, the memory is located inside the communication device.

[0041] In this embodiment of this application, the processor and the memory may alternatively be integrated into one device. In other words, the processor and the memory may alternatively be integrated together.

[0042] In a possible implementation manner, the communication device further includes a transceiver. The transceiver is configured to receive signals and / or transmit signals. For example, the transceiver may be configured to transmit a PPDU.

[0043] According to a sixth aspect, an embodiment of this application provides a communication device. The communication device includes a processor configured to execute the method shown in any one of the second aspect or possible implementation manners of the second aspect. Alternatively, the processor is configured to execute a program stored in a memory. When the program is executed, the method shown in any one of the second aspect or possible implementation manners of the second aspect is executed.

[0044] In a possible implementation manner, the memory is located outside the communication device.

[0045] In a possible implementation manner, the memory is located inside the communication device.

[0046] In this embodiment of the present application, the processor and the memory may alternatively be integrated into one device. In other words, the processor and the memory may alternatively be integrated together.

[0047] In a possible implementation, the communication device further includes a transceiver. The transceiver is configured to receive signals and / or transmit signals. For example, the transceiver may be configured to receive a PPDU.

[0048] According to a seventh aspect, an embodiment of the present application provides a communication device. The communication device includes a logic circuit and an interface, and the logic circuit is coupled to the interface. The logic circuit is configured to generate a PPDU, and the interface is configured to output the PPDU.

[0049] Optionally, the communication device further includes a memory, and the memory is configured to store at least one of a first sequence, a second sequence, a third sequence, a fourth sequence, and a fifth sequence.

[0050] Optionally, the communication device further includes a memory, and the memory is configured to store at least one of a sequence carried by a first STF and a sequence carried by a first LTF.

[0051] According to an eighth aspect, an embodiment of the present application provides a communication device. The communication device includes a logic circuit and an interface, and the logic circuit is coupled to the interface. The interface is configured to input a PPDU, and the logic circuit is configured to process the PPDU.

[0052] According to a ninth aspect, an embodiment of the present application provides a computer-readable storage medium. The computer-readable storage medium is configured to store a computer program. When the computer program is executed on a computer, the method shown in any one of the first aspect or the possible implementation manners of the first aspect is executed.

[0053] According to the tenth aspect, an embodiment of this application provides a computer-readable storage medium. The computer-readable storage medium is configured to store a computer program. When the computer program is executed on a computer, the method shown in any one of the second aspect or the possible implementation manners of the second aspect is executed.

[0054] According to the eleventh aspect, an embodiment of this application provides a computer program product. The computer program product includes a computer program or computer code (which may also be referred to as instructions). When the computer program or computer code is executed on a computer, the method shown in any one of the first aspect or the possible implementation manners of the first aspect is executed.

[0055] According to the twelfth aspect, an embodiment of this application provides a computer program product. The computer program product includes a computer program or computer code (which may also be referred to as instructions). When the computer program or computer code is executed on a computer, the method shown in any one of the second aspect or the possible implementation manners of the second aspect is executed.

[0056] According to the thirteenth aspect, an embodiment of this application provides a computer program. When the computer program is executed on a computer, the method shown in any one of the first aspect or the possible implementation manners of the first aspect is executed.

[0057] According to the fourteenth aspect, an embodiment of this application provides a computer program. When the computer program is executed on a computer, the method shown in any one of the second aspect or the possible implementation manners of the second aspect is executed.

[0058] According to the 15th aspect, the embodiments of this application provide a wireless communication system. The wireless communication system includes a transmitting end and a receiving end. The transmitting end is configured to execute the method shown in any one of the 1st aspect or the possible implementation manners of the 1st aspect. The receiving end is configured to execute the method shown in any one of the 2nd aspect or the possible implementation manners of the 2nd aspect. Brief Description of the Drawings

[0059]

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[0060] To make the purpose, technical solution and advantages of this application clearer, this application will be further described below with reference to the accompanying drawings.

[0061] Terms such as "first", "second", etc. in the specification, claims and accompanying drawings of this application are only used to distinguish different objects and are not used to describe a specific order. Furthermore, terms such as "including" and "having" and any other variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device including a series of steps or units is not limited to the listed steps or units, and optionally further includes steps or units not listed, or optionally further includes other specific steps or units of the process, method, product or device.

[0062] As used herein, "embodiment" means that a particular feature, structure or characteristic described in combination with an embodiment may be included in at least one embodiment of this application. The phrases shown in various places in this specification do not necessarily refer to the same embodiment, nor are they exclusive, independent or optional embodiments from other embodiments. It can be explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0063] In this application, "at least one (item)" means one or more, "a plurality" means two or more, and "at least two (items)" means two or three or more. "And / or" is used to describe the association relationship between related objects, indicating that three relationships may exist. For example, "A and / or B" may indicate that only A exists, only B exists, or both A and B exist. A and B may be singular or plural. The character " / " generally indicates an "or" relationship between related objects. "At least one of the following" or a similar expression means any combination of these items. For example, at least one of a, b, or c may indicate a, b, c, "a and b", "a and c", "b and c", or "a and b and c".

[0064] The technical solution provided in this application may be applicable to a wireless local area network (WLAN) system, such as Wi-Fi. For example, the method provided in this application is applicable to IEEE 802.11 series protocols such as 802.11a / b / g protocol, 802.11n protocol, 802.11ac protocol, 802.11ax protocol, 802.11be protocol or future generation protocols. Examples are not enumerated here. The technical solution provided in this application may be further applicable to a wireless personal area network (WPAN) based on UWB technology. For example, the method provided in this application is applicable to IEEE 802.15 series protocols such as 802.15.4a protocol, 802.15.4z protocol, 802.15.4ab protocol or future generation UWB WPAN protocols. Examples are not enumerated here. The technical solution provided in this application may be further applicable to various communication systems such as the internet of things (IoT) system, vehicle-to-X (V2X) system and narrowband internet of things (NB-IoT) system, and is applicable to devices in vehicle-to-X, internet of things nodes in the internet of things (IoT), sensors, etc., smart cameras, smart remotes or smart electricity / water meters in smart homes, sensors in smart cities, etc. The technical solution provided in this application is further applicable to long term evolution (LTE) systems, 5th generation (5G) communication systems, new communication systems emerging in future communication development (e.g., 6G communication systems), etc.

[0065] Embodiments of this application are mainly described by using WLAN as an example. In particular, the network used in the IEEE 802.11 series of standards is used as an example for illustration. Those skilled in the art can easily understand that various aspects of this application can be extended to other networks using various standards or protocols, such as Bluetooth, high performance radio LAN (HIPERLAN) (a wireless standard similar to the IEEE 802.11 standard mainly used in Europe), wide area network (WAN), or other networks known or to be developed in the future. Therefore, regardless of the coverage area used and the wireless access protocol used, the various aspects provided in this application are applicable to any suitable wireless network.

[0066] The method provided in this application may be implemented by a communication device in a wireless communication system. For example, the communication device may be an access point (AP) or a station (STA).

[0067] An access point is a device with a wireless communication function, which supports communication or detection by using the WLAN protocol and has the function of communicating or detecting with other devices (such as stations or other access points) in the WLAN network. Obviously, it may further have the function of communicating or detecting with other devices. Alternatively, the access point corresponds to a bridge that connects a wired network and a wireless network. The main function of the access point is to connect various wireless network clients together and then connect the wireless network to Ethernet. In a WLAN system, the access point may be called an access point station (AP STA). The device with a wireless communication function may be the entire device, or a chip or processing system installed in the entire device. The device installed with the chip or processing system may realize the methods and functions in the embodiments of this application under the control of the chip or processing system. The AP in the embodiments of this application is a device that provides services to the STA and may support the 802.11 series of protocols, subsequent protocols, etc. For example, the access point may be an access point for a terminal (such as a mobile phone) to access a wired (or wireless) network and is mainly arranged in homes, buildings, and parks. The typical coverage radius is from dozens of meters to more than 100 meters. Obviously, the access point may be alternatively arranged outdoors. In other examples, the AP may be a communication entity, such as a communication server, router, switch, or bridge, or the AP may include various forms of macro base stations, micro base stations, relay stations, etc. Obviously, the AP may be alternatively a chip or processing system in various forms of these devices for realizing the methods and functions in the embodiments of this application. The access point in this application may be a HE AP or an EHT AP, or an access point applicable to future Wi-Fi standards.

[0068] A station is a device having a wireless communication function, supporting communication or detection by using the WLAN protocol, and having the ability to communicate or detect with other stations or access points within a WLAN network. In a WLAN system, a station may be referred to as a non-access point station (non-AP STA). For example, a STA is any user communication device that enables a user to communicate with or detect an AP and further communicate with the WLAN. The device having the wireless communication function may be the entire device, or may be a chip or a processing system installed in the entire device. The device in which the chip or the processing system is installed may implement the methods and functions in the embodiments of this application under the control of the chip or the processing system. For example, a station may be a wireless communication chip, a wireless sensor, or a wireless communication terminal, and may also be referred to as a user. In other examples, a station may be a mobile phone, a tablet computer, a set-top box, a smart TV, a smart wearable device, an in-vehicle communication device, or a computer supporting a Wi-Fi communication function.

[0069] A WLAN system can provide high-speed and low-latency transmission. With the continuous development of WLAN application scenarios, the WLAN system can be applied to more scenarios or industries, such as the Internet of Things industry, vehicle-to-X industry, banking industry, enterprise offices, exhibition halls in stadiums, concert halls, hotel rooms, dormitories, hospital wards, classrooms, supermarkets, squares, streets, production factories and warehouses. Devices that support WLAN communication or detection (such as access points or stations) include sensor nodes in smart cities (such as smart water meters, smart electricity meters or smart air detection nodes), smart devices in smart homes (such as smart cameras, projectors, displays, TVs, stereos, refrigerators or washing machines), nodes in the Internet of Things, entertainment terminals (such as AR, VR or other wearable devices), smart devices in smart offices (such as printers, projectors, speakers or stereos), vehicle-to-X devices in vehicle-to-X, infrastructure in daily life scenarios (such as vending machines, self-service navigation stations in supermarkets, self-service cash register devices or self-service ordering machines), devices in large-scale sports and concert venues, etc. It is obvious that, for example, access points and stations can be devices used in vehicle-to-X, Internet of Things nodes in the Internet of Things, sensors, etc., smart cameras, smart remote controls and smart water / electricity meters in smart homes, sensors, etc. in smart cities. The specific forms of STAs and APs are not limited in the embodiments of this application and are merely examples for the purpose of explanation here.

[0070] For example, a communication system to which the method provided in this application can be applied may include an access point and a station. For example, this application is applicable to scenarios where an AP communicates with or detects a STA within a WLAN. Optionally, the AP may communicate with or detect a single STA, or the AP may communicate with or detect multiple STAs simultaneously. Specifically, the communication or detection between the AP and multiple STAs may be distinguished into a downlink transmission in which the AP simultaneously transmits signals to multiple STAs and an uplink transmission in which multiple STAs transmit signals to the AP. Both the AP and the STA may support a WLAN communication protocol. The communication protocol may include protocols of the IEEE 802.11 series. For example, it is applicable to the 802.11be standard, and obviously, it is also applicable to standards later than 802.11be.

[0071] Figure 1 is a diagram of the architecture of a communication system according to an embodiment of this application. The communication system may include one or more APs and one or more STAs. Figure 1 shows two access points, namely AP1 and AP2, and three stations, namely STA1, STA2, and STA3. It can be understood that one or more APs may communicate with one or more STAs. Obviously, an AP may communicate with an AP, and a STA may communicate with a STA.

[0072] In Figure 1, an example where the STA is a mobile phone and the AP is a router is used, and it can be understood that this does not mean that the types of APs and STAs in this application are limited. Furthermore, Figure 1 shows only two APs and three STAs. However, more or fewer APs or STAs may exist. This is not limited in this application.

[0073] To facilitate the description, the method provided in the embodiments of this application will be described below by way of example using a transmitting end and a receiving end. The transmitting end may include an AP, the receiving end may include a STA, or the transmitting end may include a STA and the receiving end may include an AP, or both the transmitting end and the receiving end are APs, or both the transmitting end and the receiving end are STAs.

[0074] The symbols shown below may be referred to as OFDM symbols, and it can be understood that the description of the OFDM symbols may also be as follows.

[0075] Orthogonal frequency division multiplexing is a multi-carrier transmission technology. This technology may use a number of adjacent orthogonal sub-carriers, and each sub-carrier may be modulated by using a modulation technique. Therefore, the orthogonal frequency division multiplexing technology can achieve high-speed transmission and can effectively withstand frequency selective fading. In the WLAN communication protocol, each OFDM symbol may include at least one of the following, namely, a pilot sub-carrier, a data sub-carrier, a direct current sub-carrier, and a guard sub-carrier. A pilot sub-carrier is a sub-carrier in which a sequence is arranged or carried in an OFDM symbol, and a data sub-carrier is a sub-carrier in which data is arranged or carried. In a communication system, the pilot sub-carrier may be used to help detect and correct the sub-carrier phase offset to improve the accuracy of the data sub-carrier resolution. The description of the OFDM symbol is applicable to all the embodiments shown below.

[0076] FIG. 2 is a schematic flowchart of a communication method based on a PPDU according to an embodiment of this application. As shown in FIG. 2, the method includes the following steps.

[0077] 201: The transmitting end generates a PPDU.

[0078] For a specific description of the PPDU, refer to the following description. For example, for the content of the PPDU, refer to the following description in FIGS. 3a to 3c, or refer to the following description in FIGS. 4a to 4c, or refer to the following description in FIG. 5, or refer to the following description in FIGS. 6a to 6c, or refer to the following description in FIGS. 7a to 7c.

[0079] 202: The transmitting end transmits the PPDU, and correspondingly, the receiving end receives the PPDU.

[0080] 203: The receiving end processes the PPDU.

[0081] The receiving end may process the PPDU based on each field included in the PPDU, and different fields may have different processing methods. For a specific processing method of the receiving end, refer to the following description. For example, the receiving end may process the PPDU based on the PPDU shown in FIGS. 3a to 3c, or may process the PPDU based on the PPDU shown in FIGS. 4a to 4c, or may process the PPDU based on the PPDU shown in FIG. 5, or may process the PPDU based on the PPDU shown in FIGS. 6a to 6c, or may process the PPDU based on the PPDU shown in FIGS. 7a to 7c.

[0082] Based on the PPDU provided in the embodiments of this application, for example, the PPDU shown in FIGS. 3a to 3c, or the PPDU shown in FIGS. 4a to 4c, the receiving end can clearly identify the physical layer version or format of the PPDU. This can further maintain backward compatibility. Based on the PPDU shown in FIG. 5, the transmitting end can achieve long-distance transmission. This can further increase the transmission distance of the PPDU and increase the coverage area of the Wi-Fi signal. Therefore, even when the distance between the receiving end and the transmitting end is long, the receiving end can still accurately demodulate the PPDU. Based on the PPDU shown in FIGS. 6a to 6c, or the PPDU shown in FIGS. 7a to 7c, backward compatibility can be ensured. Furthermore, the transmission distance of the PPDU can be increased, and the coverage area of the Wi-Fi signal can be increased.

[0083] The PPDU provided in the embodiments of this application will be described in detail below.

[0084] In some embodiments of this application, a PPDU is provided. The PPDU can ensure backward compatibility and further implement more functions such as long-distance transmission function or high-speed transmission function. The embodiments of this application provide PPDUs in more formats, so that the next-generation devices can effectively distinguish between the new PPDU (i.e., the PPDU provided in the embodiments of this application) and the old PPDU (e.g., the PPDU proposed before the embodiments of this application, such as EHT PPDU or HE PPDU). In this way, the receiving end automatically detects the format of the PPDU. Therefore, the embodiments of this application provide the following two types of PPDUs.

[0085] The first type of PPDU may include an L-STF, an L-LTF, an L-SIG field, a first BPSK mark field, and a second BPSK mark field, as shown in FIGS. 3a to 3c. For the specific description of the first BPSK mark 1 field and the second BPSK mark 2 field, refer to the following description of the extended range (ER) BPSK mark 1 field and the ER BPSK mark 2 field.

[0086] The first BPSK mark field and the second BPSK mark field may each occupy one OFDM symbol. When the two fields each occupy one OFDM symbol, the first BPSK mark field may also be referred to as the first BPSK mark symbol, and the second BPSK mark field may also be referred to as the second BPSK mark symbol. The OFDM symbol shown above is merely an example. For ease of explanation, hereinafter, the first BPSK mark field will be used as the ER BPSK mark 1 field, and the second BPSK mark field will be used as the ER BPSK mark 2 field to provide an explanation. Obviously, the first BPSK mark field and the second BPSK mark field may alternatively have other names or replacement methods. This is not limited in the embodiments of this application. The ER BPSK mark 1 field and the ER BPSK mark 2 field may be implemented in the following manner.

[0087] Implementation method 1: The ER BPSK mark 1 field and the ER BPSK mark 2 field may be different. One of the ER BPSK mark 1 field or the ER BPSK mark 2 field may be the same as the L-SIG field, and the other of the ER BPSK mark 1 field or the ER BPSK mark 2 field may not be the same as the L-SIG field.

[0088] In one example, the ER BPSK Mark 1 field is the same as the L-SIG field, and the ER BPSK Mark 2 field is obtained by multiplying the data subcarriers in the L-SIG field by a sequence whose elements include -1 (this is merely an example). For a wake-up radio (WUR) PPDU, the BPSK Mark 1 field and the BPSK Mark 2 field in the WUR PPDU are each obtained by multiplying the data subcarriers in the L-SIG field by a sequence whose elements are -1. The sequence whose elements are -1 shown here can also be understood as follows. All elements in the sequence are -1. However, at least one of the ER BPSK Mark 1 field and the ER BPSK Mark 2 field shown in the embodiments of this application is different from the BPSK Mark 1 field and the BPSK Mark 2 field in the WUR PPDU, so that the PPDU shown in the embodiments of this application can be distinguished from the WUR PPDU.

[0089] The PPDU shown in the embodiments of this application may be further distinguished from the HE PPDU and the EHT PPDU. For example, the first symbol following the L-SIG field in the HE PPDU is the same as the L-SIG field, and the second symbol following the L-SIG field is the HE-SIG-A field. The second symbol following the L-SIG field in the PPDU provided in the embodiments of this application is obtained by multiplying the data subcarriers in the L-SIG field by a sequence whose elements include -1. Therefore, the PPDU provided in the embodiments of this application is different from the HE PPDU. Thus, the receiving end can distinguish between the HE PPDU and the PPDU provided in the embodiments of this application based on the ER BPSK Mark 2 field. In another example, the first symbol following the EHT PPDU is the same as the L-SIG field, and the second symbol following the L-SIG field is the first symbol in the U-SIG field. Therefore, the PPDU provided in the embodiments of this application is different from the EHT PPDU. Thus, the receiving end can distinguish between the EHT PPDU and the PPDU provided in the embodiments of this application based on the ER BPSK Mark 2 field. It can be understood that the following description is also applicable to the distinction between the PPDU shown in the embodiments of this application and the WUR PPDU, HE PPDU, and EHT PPDU.

[0090] In another example, the ER BPSK Mark 2 field may be the same as the L-SIG field, and the ER BPSK Mark 1 field is obtained by multiplying the data subcarriers in the L-SIG field by a sequence whose elements include -1. Thus, the receiving end may distinguish the PPDU provided in the embodiments of this application from the PPDUs of other formats based on the BPSK Mark 1 field.

[0091] It can be understood that "the ER BPSK mark 2 field or the ER BPSK mark 1 field shown in the embodiments of this application is obtained by multiplying the data subcarriers in the L-SIG field by a sequence whose elements include -1". The "sequence whose elements include -1" is merely an example. For example, the sequence whose elements include -1 can alternatively be replaced by a sequence whose elements include +1 and -1 (which can also be understood as a sequence including +1 and -1), or a sequence whose elements include +1, 0, and -1 (which can also be understood as a sequence including +1, 0, and -1). It can be understood that the sequences shown here differ not only in terms of the elements included, but also in terms of the values and orders of the elements within the sequences. For example, the sequence whose elements include +1 and -1 may include +1, -1, +1, -1, or may include -1, +1, -1, +1. Examples are not enumerated here.

[0092] It can be understood that it may be understood as follows that field A shown in the embodiments of this application is the same as field B. The sequence carried in field A is the same as the sequence carried in field B. For example, it can be understood as follows that the ER BPSK mark 1 field is the same as the L-SIG field. The sequence carried in the ER BPSK mark 1 field is the same as the sequence carried in the L-SIG field.

[0093] Implementation method 2: The ER BPSK mark 1 field and the ER BPSK mark 2 field may be the same. For example, the ER BPSK mark 1 field and the ER BPSK mark 2 field may each be obtained by multiplying the data subcarriers in the L-SIG field by a sequence whose elements are +1. In another example, the ER BPSK mark 1 field and the ER BPSK mark 2 field may each be obtained by sequentially multiplying the data subcarriers in the L-SIG field by a mixed sequence including +1 and -1. In yet another example, the ER BPSK mark 1 field and the ER BPSK mark 2 field may each be obtained by sequentially multiplying the data subcarriers in the L-SIG field by a mixed sequence including -1 and +1 (note that the order of the mixed sequences shown here is different from the order of the above mixed sequences). In this implementation method, the implementation is simple, and the same operation may be performed on the ER BPSK mark 1 field and the ER BPSK mark 2 field.

[0094] It should be noted that the fact that the above-mentioned ER BPSK mark 1 field (or ER BPSK mark 2 field) is the same as the L-SIG field can be understood as follows. The ER BPSK mark 1 field (or the ER BPSK mark 2 field) may be obtained by multiplying the L-SIG field by a sequence whose elements are +1. In other words, when the transmitting end generates a PPDU, the ER BPSK mark 1 field is obtained by multiplying the L-SIG field by a sequence whose elements are +1, or the sequence in the L-SIG field is directly used as the ER BPSK mark 1 field. However, regardless of which method is used, the final result is that the ER BPSK mark 1 field is the same as the L-SIG field. Therefore, the two methods are not particularly distinguished in the embodiments of this application.

[0095] Implementation Method 3: The ER BPSK Mark 1 field or the ER BPSK Mark 2 field is obtained based on the L-SIG field and a third sequence. Optionally, the elements in the third sequence may include +1 and -1 (which can also be understood as follows: the third sequence includes +1 and -1). Optionally, the elements in the third sequence may include +1, 0, and -1 (which can also be understood as follows: the third sequence includes +1, 0, and -1. The third sequence shown here only shows examples of elements, and it can be understood that the specific values of each element in the third sequence are not limited in the embodiments of this application).

[0096] In one example, one of the ER BPSK Mark 1 field or the ER BPSK Mark 2 field is obtained based on the L-SIG field and a third sequence, and the other of the ER BPSK Mark 1 field or the ER BPSK Mark 2 field is obtained based on the L-SIG field and a sequence whose elements include -1. For example, the ER BPSK Mark 1 field may be obtained by multiplying the data subcarriers in the L-SIG field in sequence (which can also be understood as sequentially) by a sequence including +1 and -1. The ER BPSK Mark 2 field may be obtained by multiplying the L-SIG field by a sequence whose elements include -1.

[0097] In another example, one of the ER BPSK Mark 1 field or the ER BPSK Mark 2 field is obtained based on the L-SIG field and a sequence whose elements include +1 and -1, and the other of the ER BPSK Mark 1 field or the ER BPSK Mark 2 field is obtained based on the L-SIG field and a sequence whose elements include +1, 0, and -1.

[0098] In yet another example, the ER BPSK mark 1 field and the ER BPSK mark 2 field are each obtained based on a sequence in which the elements include +1 and -1. However, the value of at least one element in the sequence used by the ER BPSK mark 1 field is different from the value of the element at the corresponding position in the sequence used by the BPSK mark 2 field. For example, the sequence used by the ER BPSK mark 1 field includes +1, -1, +1, -1. The length of the sequence is not limited in the embodiments of this application. The sequence used by the ER BPSK mark 2 field includes -1, +1, -1, +1. Examples are not enumerated here.

[0099] Based on the ER BPSK mark 1 field and the ER BPSK mark 2 field shown above, the receiving end may identify the type of the PPDU received by the receiving end by multiplying the first symbol and / or the second symbol following the L-SIG field by the corresponding sequence. The sequence here may be a sequence in which the elements include -1, a sequence in which the elements include +1 and -1, or a sequence in which the elements include +1, 0, and -1. After receiving the PPDU based on the ER BPSK mark 1 field and the ER BPSK mark 2 field shown above, the receiving end (for example, a third-party device) may identify the format, physical layer version, etc. of the PPDU based on the ER BPSK mark 1 field and the ER BPSK mark 2 field.

[0100] The length of each of the above sequences may be determined based on the OFDM symbol. When the above sequence needs to be applied to the data subcarriers, the length of the sequence may be 48 bits, in other words, the sequence includes 48 elements. When the above sequence needs to be applied to the data subcarriers and the pilot subcarriers, the length of the sequence may be 52 bits, in other words, the sequence includes 52 elements. It can be understood that when the number of data subcarriers and / or the number of pilot subcarriers changes, the length of the sequence may also change.

[0101] It should be noted that the names of the ER BPSK mark 1 field and the ER BPSK mark 2 field shown in the embodiments of this application are merely examples. For example, the names of the ER BPSK mark 1 field and the ER BPSK mark 2 field may alternatively have other names based on the specific function, format, or physical layer version of the PPDU. For example, the PPDU is an extended range PPDU or a long range (LR) PPDU. In this case, the ER BPSK mark 1 field may also be replaced with an extended BPSK mark 1 field, an LR BPSK mark 1 field, etc., and the ER BPSK mark 2 field may be replaced with an extended BPSK mark 2 field, an LR BPSK mark 2 field, etc. Examples are not enumerated here.

[0102] In one example, FIG. 3a is a diagram of the structure of a PPDU according to an embodiment of this application. As shown in FIG. 3a, the L-STF, L-LTF, L-SIG fields, ER BPSK mark 1 field, and ER BPSK mark 2 field shown in this embodiment of this application may be included in the first part of the PPDU. For example, the transmission time lengths of the L-STF and L-LTF may each be 8 microseconds, and the transmission time lengths of the L-SIG field, ER BPSK mark 1 field, and ER BPSK mark 2 field may each be 4 microseconds. If transmitting one OFDM symbol requires 4 microseconds, the L-STF and L-LTF may each occupy two OFDM symbols, and the L-SIG field, ER BPSK mark 1 field, and ER BPSK mark 2 field may each occupy one OFDM symbol.

[0103] In another example, FIG. 3b is a diagram of the structure of a PPDU according to an embodiment of this application. As shown in FIG. 3b, the bandwidth for transmitting the second part of the PPDU may be smaller than the bandwidth for transmitting the first part of the PPDU. Therefore, when the power spectral density is not limited, by reducing the transmission bandwidth of the second part of the PPDU and increasing the power spectral density, the transmission distance of the second part can be effectively increased, thereby increasing the coverage area of the Wi-Fi signal. For example, one resource unit (RU) or multiple resource units (MRUs) may be used for transmission. The size of the RU or MRU may be a 26-tone RU, a 52-tone RU, a 52+26-tone MRU, a 106-tone RU, or a 106+26-tone MRU. The examples of the RU or MRU shown here are shown by using the RU or MRU at 20 MHz as an example, and it can be understood that they are not listed here for the cases of bandwidths of 40 MHz or 80 MHz. For example, when the bandwidth is larger than 20 MHz, replication may be performed based on the 20 MHz allocation state to obtain a 40 MHz allocation state, an 80 MHz allocation state, etc.

[0104] In yet another example, FIG. 3c is a diagram of the structure of a PPDU according to an embodiment of this application. As shown in FIG. 3c, the second part of the PPDU may be repeatedly transmitted in the frequency domain. The second part shown in FIG. 3c is repeatedly transmitted in the frequency domain. Therefore, it is also possible that the second part is realized through replication in the frequency domain. In this way, the receiving end may perform maximum-ratio combining (MRC) in the frequency domain to increase the transmission distance and coverage area of the Wi-Fi signal.

[0105] It can be understood that the content of the second part of the PPDU may be determined based on the PPDU format or the physical layer version. This is not limited in the embodiments of this application. For example, for the content of the second part of the PPDU, refer to the following descriptions in FIGS. 5, 6A-6C, and 7A-7C.

[0106] The processing of the PPDU by different devices will be described in detail below.

[0107] The receiving end shown in the embodiments of this application may include a target receiving end and a third-party device. The target receiving end can be understood as the transmission target of the transmitting end (or the receiving target of the PPDU). The third-party device may include a device that can identify the PPDU and / or a device that cannot identify the PPDU.

[0108] In one example, the ER BPSK mark 1 field and the ER BPSK mark 1 field may be used to prevent incorrect PPDU format detection and / or to spoof a high-throughput device (or a higher-level backward-compatible device that may also be called a high-throughput device). After receiving the PPDU provided in the embodiments of this application, a device that cannot identify the PPDU (for example, a legacy device or a device that does not support long-distance transmission of the PPDU) cannot identify the PPDU, and thus "identifies" the PPDU as a non-high-throughput PPDU including the L-STF, L-LTF, L-SIG fields, and the data Data field, that is, a legacy PPDU.

[0109] In another example, a device that can identify the PPDU may identify that the PPDU is an extended range PPDU, a long-distance PPDU, etc. based on the ER BPSK mark 1 field and the ER BPSK mark 2 field.

[0110] In yet another example, after receiving a PPDU, a third-party device may further identify the physical layer version, format, etc. of the PPDU based on the ER BPSK mark 1 field and the ER BPSK mark 1 field, and may know that the PPDU is not sent to the third-party device. Therefore, the third-party device may terminate the transmission in advance to save energy. After receiving the PPDU provided in the embodiments of this application, the third-party device identifies the PPDU, calculates the length of the PPDU based on the L-STF, L-LTF, and L-SIG fields. As a result, in the transmission process of the PPDU, the third-party device maintains a non-transmission state (which can also be understood as a silent state) to prevent interference with the transmission of the PPDU, thereby realizing backward compatibility. It can be understood that the distance between the third-party device and the transmitting end may be shorter than the distance between the target receiving end and the transmitting end.

[0111] In yet another example, when the distance between the transmitting end and the target receiving end is long (longer than the distance between the transmitting end and the third-party device), the target receiving end may erroneously consider that the first part of the PPDU is noise. Therefore, the target receiving end cannot effectively acquire the first part of the PPDU. Obviously, when the target between the transmitting end and the target receiving end is close, the target receiving end may also receive the PPDU and acquire the first part of the PPDU. Therefore, at least one of the following, namely, the format of the PPDU and the physical layer version of the PPDU, can be known based on the first part of the PPDU.

[0112] It can be understood that the above description regarding the target receiving end and the third-party device is also applicable to the second type of PPDU shown below.

[0113] Based on the first part of the PPDU shown in the embodiments of this application, a third-party device or a target receiving end that can receive the PPDU may perform the following processing.

[0114] For example, after receiving a PPDU, a third-party device may identify the L-SIG field and the ER BPSK Mark 1 field. If the L-SIG field is the same as the ER BPSK Mark 1 field and the ER BPSK Mark 2 field is not the HE-SIG-A field, the third-party device may identify the format of the PPDU or the physical layer version of the PPDU. For example, the PPDU may be an extended range PPDU, or the PPDU may be an ultra-long range PPDU, or the PPDU may be a PPDU in Wi-Fi 8. The format, physical layer version, or name of the PPDU is not limited in the embodiments of this application.

[0115] In another example, after receiving a PPDU, a third-party device multiplies the data subcarriers in the L-SIG field separately by a sequence in which the elements are -1 to obtain sequence A, multiplies the data subcarriers in the L-SIG field by a sequence in which the elements are +1 to obtain sequence B, and then determines the relationship between sequence A, sequence B, a sequence including the data subcarriers in the ER BPSK mark 1 field, and a sequence including the data subcarriers in the ER BPSK mark 2 field. If sequence A is the same as the ER BPSK mark 1 field and the ER BPSK mark 2 field separately, in other words, if sequence A is the same as both the ER BPSK mark 1 field and the ER BPSK mark 2 field, or if the probability that sequence A is the same as the ER BPSK mark 1 field and the ER BPSK mark 2 field is greater than a first probability, the PPDU may be determined to be a WUR PPDU. If sequence A is the same as the ER BPSK mark 1 field and sequence B is the same as the ER BPSK mark 2 field, or if the probability that sequence B is the same as the ER BPSK mark 2 field is greater than a second probability, the PPDU may be determined to be an ER PPDU. It can be understood that the first probability (e.g., 90%, 95% or 99%) and the second probability (e.g., 90%, 95% or 99%) shown above are merely examples. The first probability and the second probability may be the same or different. This is not limited in the embodiments of this application.

[0116] In yet another example, after receiving a PPDU, a third-party device separately multiplies the first symbol (or the second symbol) following the L-SIG field by a sequence with elements being -1 to obtain sequence C, multiplies the first symbol (or the second symbol) following the L-SIG field by a sequence including elements +1 and -1 to obtain sequence D, and then may determine the relationship between sequence C and the L-SIG field and the relationship between sequence D and the L-SIG field. If sequence C is the same as the L-SIG field, or if the probability that sequence C is the same as the L-SIG field is greater than a certain probability, it may be determined that the PPDU is a WUR PPDU. If sequence D is the same as the L-SIG field, or if the probability that sequence D is the same as the L-SIG field is greater than a certain probability, it may be determined that the PPDU is an ER PPDU.

[0117] It can be understood that the above-described method of processing a PPDU by a third-party device is merely an example. The target receiving end may further perform, for example, PPDU detection, automatic gain control, and coarse time synchronization and coarse frequency synchronization based on the L-STF. In other examples, channel estimation, and fine time synchronization and fine frequency synchronization may be performed based on the L-LTF. In still other examples, signaling information necessary for demodulating the subsequent data part may be obtained based on the L-SIG field. Examples are not enumerated here. For the descriptions of the L-STF, L-LTF, and L-SIG fields, refer to the relevant protocols, etc. This is not limited in the embodiments of this application.

[0118] The second type of PPDU may include an L-STF, an L-LTF, an L-SIG field, an RL-SIG field, and a U-SIG field, as shown in FIGS. 4a to 4c. The U-SIG field may be described as follows.

[0119] The U-SIG field contains at least one of the following information, namely, the physical layer version of the PPDU and the format of the PPDU. The version number of the physical layer version of the PPDU may be greater than 0, or the physical layer version of the PPDU may indicate that the PPDU is an EHT PPDU or a PPDU in a subsequent generation of standards. The U-SIG field may be present in the PPDU in the 802.11be standard and subsequent generations of standards. For example, when the U-SIG field where the physical layer version is located indicates 1, this indicates that the PPDU is a Wi-Fi 8 PPDU. The format of the PPDU indicates whether the format of the PPDU is an extended range PPDU format or whether the format of the PPDU is the format in a Wi-Fi 8 PPDU. For example, the U-SIG field may further include a transmission opportunity, a basic service set color, etc. The transmission opportunity may be used to recommend a transmission opportunity to prevent a third-party device from interfering with the transmission in the transmission opportunity, thereby achieving a better transmission protection effect.

[0120] For example, the content of the L-SIG field may be the same as the content of the RL-SIG field. For example, the length may be a multiple of 3. The L-SIG field may include a length field and a rate field, and the length field and the rate field may be used for the time duration of the remaining part following the L-SIG field. For example, the receiving end may calculate the time duration of the subsequent part of the L-SIG field based on the length field and the rate field. The L-SIG field includes a length field and a rate field. The transmitting end may indirectly indicate the transmission time duration defined first in the PPDU based on the length field and the rate field within the L-SIG field. The rate field may be fixedly set to 6 megabits per second (Mbps). Since the rate field is set to a fixed value, the transmission time duration of the PPDU is indirectly indicated by using the length field. The formula for calculating the transmission time duration Length of the length field is as follows. [Number]

[0121] SignalExtension is a parameter related to the transmission frequency band. When the device operates at 2.4 GHz, the parameter is 6 μs (microseconds). When the device operates at 5 GHz or 6 GHz, the parameter is 0 μs. TXTIME represents the transmission time duration defined first for the entire PPDU. For the PPDU shown in the embodiments of this application, m = 0 (it can be seen from the above formula that the length is a multiple of 3). The value of m may be used by the receiving end to distinguish from the HE PPDU in the automatic detection process. For example, for the HE PPDU, the value of m is 1 or 2.

[0122] It can be understood that the above description of indicating the transmission time duration of the PPDU is merely an example and should not be construed as a limitation to the embodiments of this application.

[0123] For ease of explanation, in the embodiments shown in this application, "field" is used as an example, and it should be noted that "field" and "sub-field" are not particularly distinguished. Although "field" and "sub-field" are not particularly distinguished in the embodiments shown in this application, those skilled in the art can adaptively distinguish the relationships between the fields shown in this application.

[0124] FIG. 4a is a diagram of the structure of a PPDU according to an embodiment of this application. As shown in FIG. 4a, the L-STF, L-LTF, L-SIG fields, RL-SIG field, and U-SIG field shown in this embodiment of this application may be included in the first part of the PPDU. For example, the transmission time lengths of L-STF and L-LTF may each be 8 microseconds, the transmission time lengths of the L-SIG field and RL-SIG field may each be 4 microseconds, and the transmission time length of the U-SIG field may be 8 microseconds or 16 microseconds. Optionally, FIG. 4b is a diagram of the structure of a PPDU according to an embodiment of this application. Optionally, FIG. 4c is a diagram of the structure of a PPDU according to an embodiment of this application. For the descriptions of FIGS. 4b and 4c, refer to FIGS. 3b and 3c. Details will not be described again here. The second part of the PPDU is not limited in the embodiments of this application. For example, refer to the following descriptions in FIGS. 5, 6a-6c, and 7a-7c.

[0125] The processing of the PPDU by different devices will be described in detail below. It can be understood that for the specific descriptions of the target receiving end and the third-party device, refer to the above description of the first type of PPDU. Details will not be described again here.

[0126] Based on the first part of the PPDU shown in the embodiments of this application, a third-party device or a target receiving end capable of receiving the PPDU may perform the following processing.

[0127] For example, after receiving a PPDU, a third-party device may parse the version number indicated in the U-SIG field. If the version number is greater than 0, for example, if the version number is 1, it may be determined that the PPDU is a PPDU in Wi-Fi 8. If the version number is equal to 0, it may be determined that the PPDU is an EHT PPDU (this is just an example).

[0128] In another example, after receiving a PPDU, a third-party device may parse the format of the PPDU indicated in the U-SIG field. For example, for downlink transmission, if the format indicated in the U-SIG field is 0, this may indicate that the PPDU is a single-user transmission; if the format indicated in the U-SIG field is 1, this may indicate that the PPDU is a multi-user orthogonal frequency division multiple access (OFDMA); if the format indicated in the U-SIG field is 2, this may indicate that the PPDU is a multi-user (MU) multiple-input multiple-output (MIMO) transmission; or if the format indicated in the U-SIG field is 3, this may indicate that the PPDU is a long-distance transmission. For uplink transmission, if the format indicated in the U-SIG field is 0, this may indicate that the PPDU is a single-user transmission; if the format indicated in the U-SIG field is 1, this may indicate that the format of the PPDU is a trigger-based transmission; or if the format indicated in the U-SIG field is 2, this may indicate that the format of the PPDU is a long-distance transmission. It should be understood that the above relationship between the value of the format indicated in the U-SIG field and the format of the PPDU is merely an example and should not be construed as a limitation on the embodiments of this application.

[0129] In yet another example, after receiving a PPDU, a third-party device may parse the PPDU based on the version number and format of the PPDU indicated in the U-SIG field. For example, when the version number of the PPDU parsed by using the U-SIG field is greater than 0, it may be further detected whether the format of the PPDU is a long-distance transmission.

[0130] In yet another example, the third-party device may further parse the transmission opportunity indicated in the U-SIG field, the basic service set color, etc. Examples are not enumerated here.

[0131] Regarding the description of parsing the L-STF, L-LTF, and L-SIG fields by the receiving end, it can be understood that relevant protocols, etc. should be referred to. This is not limited in the embodiments of this application.

[0132] Regarding the third-party device, if the third-party device does not support extended range transmission, or if the third-party device determines that it is close to the access point, the extended range transmission mode may be disabled. In other words, it should be noted that the third-party device may identify the PPDU as a legacy PPDU without determining whether the PPDU is an extended range PPDU.

[0133] The PPDU shown in the embodiments of this application, for example, the PPDU in FIGS. 3a to 3c and FIGS. 4a to 4c, can ensure backward compatibility and further realize more functions.

[0134] The WUR PPDU may be used for wake-up wireless transmission, but the WUR PPDU cannot achieve long-distance transmission. Furthermore, both the WUR synchronization field and the WUR data field are modulated through on-off keying (OOK), and some functions based on OFDM modulation such as interleaving and dual-carrier modulation cannot be realized. As a result, it cannot effectively withstand channel-selective fading.

[0135] In view of this, in some other embodiments of this application, a PPDU is further provided. The PPDU may implement long-distance transmission of the PPDU, thereby extending the coverage area of the Wi-Fi signal. For example, the coverage area of the Wi-Fi signal may be further extended based on the coverage area involved in the 802.11b protocol. Optionally, the interference prevention ability of the Wi-Fi signal may be further increased.

[0136] At least one of the first STF, the first LTF, the first SIG field, and the first data field shown below may be included in the second part of the PPDU. The first part of the PPDU may be, for example, the non-wake-up radio part in the WUR PPDU (including, for example, the L-STF, L-LTF, L-SIG field, BPSK mark 1 field, and BPSK mark 2 field), the first part shown in FIGS. 3a to 3c, or the first part shown in FIGS. 4a to 4c. It should be noted that the first part of the PPDU is not limited in the embodiments of this application. When the second part shown in the embodiments of this application is combined with the first part shown in FIGS. 3a to 3c, or combined with the first part shown in FIGS. 4a to 4c, the PPDU may implement long-distance transmission. As a result, not only can the coverage area of the Wi-Fi signal be further extended based on the 802.11b protocol, but also backward compatibility can be effectively maintained. As a result, the current version of the PPDU can be made compatible with the previous version of the PPDU. In other words, when receiving the PPDU, the legacy device may accurately parse the PPDU, have backward compatibility, and further extend the coverage area of the PPDU.

[0137] Obviously, the PPDU shown in the embodiments of this application may alternatively include only the second part. In other words, the PPDU may not include the first part shown in the embodiments of this application. In other words, the first part and the second part shown in the embodiments of this application are different parts for distinguishing between PPDUs, and it does not indicate that each PPDU needs to include two parts. For example, before the PPDU is transmitted, if the transmission opportunity has been established by both communication parties through some interactions and it is ensured that the transmission is not interfered with, the transmitter does not need to transmit the first part of the PPDU shown in the embodiments of this application.

[0138] For the sake of easy explanation, the method provided in the embodiments of this application will be described below by using an example in which the PPDU includes a first part and a second part. For example, the first part of the PPDU may include the L-STF, L-LTF, L-SIG fields, ER BPSK mark 1 field, and ER BPSK mark 2 field (for example, the first part shown in FIGS. 3a to 3c). For example, the first part of the PPDU may include the L-STF, L-LTF, L-SIG fields, RL-SIG field, and U-SIG field (for example, the first part shown in FIGS. 4a to 4c). The first part shown here is merely an example and should not be construed as a limitation to the embodiments of this application.

[0139] The second part of the PPDU in the embodiments of this application will be described in detail below. The second part of the PPDU may satisfy any one or more of the following items 1 to 5.

[0140] Item 1: The PPDU includes a first STF, the first STF is obtained based on a second STF and a first sequence, and the time length of the first STF is greater than the time length of the L-STF.

[0141] The first sequence shown in the embodiments of this application is a sequence used to extend the second STF, and the first sequence is used to extend the second STF to obtain the first STF. That is, the function of the first sequence is an extension. For example, the fact that the first STF is obtained based on the second STF and the first sequence can also be understood as follows. The first STF is obtained based on an OFDM symbol or a part of an OFDM symbol occupied by the second STF, or the sequence carried by the first STF (which may also be called the first STF sequence) is obtained by extending the sequence carried by the second STF (which may also be called the second STF sequence).

[0142] The time length can also be understood as the transmission time length or the transmission time duration. For example, if the length of each OFDM symbol is 4 microseconds, the above description can be equivalent to the number of OFDM symbols occupied by the first STF being greater than the number of OFDM symbols occupied by the L-STF. Obviously, if the time lengths of the OFDM symbols occupied by different fields are different, it cannot simply be considered equivalent to the number of OFDM symbols occupied by the first STF being greater than the number of OFDM symbols occupied by the L-STF. For example, the time length corresponding to one OFDM symbol may be 4 microseconds (referred to as 1x symbol), or the time length corresponding to one OFDM symbol may be 8 microseconds (referred to as 2x symbol), or the time length corresponding to one OFDM symbol may be 16 microseconds (referred to as 4x symbol). Examples are not enumerated here.

[0143] The second STF may include any one of an L-STF (e.g., included in the first part of the PPDU), an extremely high throughput-STF (EHT-STF), an HE-STF, a very high throughput-STF (VHT-STF), and a high throughput-STF (HT-STF). The HE-STF shown above may include the HE-STF in an HE MU PPDU or the HE-STF in a high efficient trigger based (HE-TB) PPDU. The above EHT-STF may include the EHT-STF in an EHT MU PPDU or the EHT-STF in an EHT TB PPDU.

[0144] The EHT-STF, HE-STF, VHT-STF, and HT-STF may be understood as STFs in different protocols in the 802.11 standard, and it should be noted that the STFs in different protocols may carry different sequences. Therefore, the second STF is not limited in the embodiments of this application. The second STF may be a sequence carried by an STF in a different protocol, an STF carried by a PPDU before Wi-Fi 8, or an STF that appears in a subsequent protocol. Examples are not enumerated here.

[0145] Optionally, the first sequence may be obtained based on a Barker code. Since the length of the Barker code is greater than 1, it can be understood that the Barker code shown in the embodiments of this application may also be referred to as a Barker code sequence or a Buck sequence. For example, a Barker code with a length of 2 is {+1, -1} or {+1, +1}. In this case, the first sequence may be {+1, -1} or {+1, +1}, or the first sequence may be {-1, +1} or {-1, -1} (i.e., the first sequence may be obtained by negating the Barker code), or the first sequence may be obtained by circularly shifting the Barker code. Examples are not enumerated here. In other examples, a Barker code with a length of 3 is {+1, +1, -1}. In this case, the first sequence may be {+1, +1, -1}, or the first sequence may be {-1, -1, +1} (i.e., the first sequence is obtained by negating the Barker code), or the first sequence may be obtained by circularly shifting the Barker code. For example, the first sequence is {+1, -1, +1}, or the first sequence is {-1, +1, +1}. In still other examples, a Barker code with a length of 4 is {+1, +1, -1, +1} or {+1, +1, +1, -1}. The relationship between the first sequence and the Barker code is not enumerated here. In still other examples, a Barker code with a length of 5 is {+1, +1, +1, -1, +1}, a Barker code with a length of 7 is {+1, +1, +1, -1, -1, +1, -1}, a Barker code with a length of 11 is {+1, -1, +1, +1, -1, +1, +1, +1, -1, -1, -1}, and a Barker code with a length of 13 is {+1, +1, +1, +1, +1, -1, -1, +1, +1, -1, +1, -1, +1}. The length of the Barker code shown here may be understood as the bit length, and it can be understood that Barker codes of other lengths are not enumerated here.The first sequence shown above is equal to a Barker code, or the first sequence is obtained by cyclically shifting a Barker code, or the first sequence is obtained by negating a Barker code, but it should be noted that this is merely an example. For example, the first sequence may alternatively be obtained by sorting the Barker code from the back to the front. For example, a Barker code of length 5 is {+1, +1, +1, -1, +1}. In this case, the first sequence may be {+1, -1, +1, +1, +1}.

[0146] Optionally, the first sequence may be obtained based on a maximum length sequence (MLS), or may be obtained based on a Zadoff-Chu (ZC) sequence, or may be obtained based on a Gray complementary sequence. Optionally, the elements of the first sequence may include +1. For example, the first sequence may be a sequence of all 1s (which can also be understood as follows: the first STF is obtained by simply copying the second STF). Since the function of the first sequence is to extend the sequence carried in the second STF, the specific content of the first sequence is not limited in the embodiments of this application.

[0147] The following uses an example in which the first STF is obtained based on the second STF and the first sequence, and the first sequence is obtained based on a Barker code to explain the first STF.

[0148] The OFDM symbols or parts of OFDM symbols within the second STF modulated through OFDM are extended by using Barker codes to obtain the first STF, so that the time length of the first STF becomes larger than the time length of the L-STF. The above extension method may also be considered as weighted repetition of signals in the time domain. Therefore, the receiving end may perform related processing based on the first STF, thereby improving the equivalent signal-to-noise ratio and ensuring that the receiving end can detect the PPDU in a longer range. The good correlation characteristics of the Barker code (such as autocorrelation characteristics or cross-correlation characteristics) can help the receiving end accurately detect the PPDU. (For example, the process of identifying the PPDU is to distinguish whether the PPDU is received or noise is received through correlation. Therefore, the correlation value of the PPDU is high and the correlation value of the noise is low. This can effectively improve the accuracy of detecting the PDPU.) It can be understood that the related explanations shown here are also applicable to other types of first sequences.

[0149] In a possible implementation, it can also be understood as follows that the first STF is obtained by extending the OFDM symbols within the second STF by using the first sequence. The first STF is obtained by extending the OFDM symbols occupied by the second STF by using the first sequence. When the first sequence is obtained based on the Barker code, it can be understood that the first STF is also obtained based on the Barker code and the OFDM symbols (or parts of OFDM symbols) occupied by the second STF. The OFDM symbols (or parts of OFDM symbols) are extended so that the advantages of OFDM modulation can be retained. For example, OFDM modulation can help withstand frequency-selective fading. Furthermore, the existing design can be retained. For example, methods such as OFDM modulation-based coding, OFDM modulation-based interleaving, and OFDM modulation-based frequency-domain repetition can still be retained.

[0150] In one example, an OFDM symbol having a period of 0.8 microseconds may be used. For example, the time length of one OFDM symbol is 4 microseconds, or the total time length of two OFDM symbols is 8 microseconds, and the second STF is extended based on this. For example, the OFDM symbol occupied by the second STF may be extended at the granularity of one OFDM symbol, or the OFDM symbol occupied by the second STF may be extended at the granularity of two OFDM symbols. For example, in a 20 MHz bandwidth, the sequence of the HE-STF in the HE MU PPDU in the frequency domain is

Number

[0151] In other examples, an OFDM symbol having a period of 1.6 microseconds may be used. For example, the time length of one OFDM symbol is 8 microseconds (referred to as a 2x symbol), and the second STF is extended based on this. When an OFDM symbol having a period of 1.6 microseconds is used for extension, the period of the first STF may be different from the period of the second STF (e.g., L-STF). Therefore, the first STF cannot be misrecognized as the L-STF by legacy devices. Therefore, confusion in PPDU detection is avoided. It can be understood that an OFDM symbol having a period of 3.2 microseconds may be further used. Examples are not enumerated in the embodiments of this application. For example, in a 20 MHz bandwidth, the sequence of the HE-STF in the HE TB PPDU in the frequency domain is

Number

[0152] A Barker code with a length of 11 is used as an example. In this case, the first STF may include {+HE-STF symbol, -HE-STF symbol, +HE-STF symbol, +HE-STF symbol, -HE-STF symbol, +HE-STF symbol, +HE-STF symbol, +HE-STF symbol, -HE-STF symbol, -HE-STF symbol, -HE-STF symbol}. The -HE-STF symbol indicates that the value of each sub-carrier of the HE-STF symbol is negated. It can be understood that the HE-STF symbol shown here may be understood as one OFDM symbol occupied by the HE-STF. Obviously, the HE-STF may alternatively occupy two OFDM symbols or the like. This is not limited in the embodiments of this application.

[0153] A Barker code of length 11 is still used as an example. In this case, the first STF may include {+L-STF symbol 1, +L-STF symbol 2, -L-STF symbol 1, -L-STF symbol 2, +L-STF symbol 1, +L-STF symbol 2, +L-STF symbol 1, +L-STF symbol 2, -L-STF symbol 1, -L-STF symbol 2, +L-STF symbol 1, +L-STF symbol 2, +L-STF symbol 1, +L-STF symbol 2, +L-STF symbol 1, +L-STF symbol 2, -L-STF symbol 1, -L-STF symbol 2, -L-STF symbol 1, -L-STF symbol 2, -L-STF symbol 1, -L-STF symbol 2}. Alternatively, the first STF may include {+L-STF symbol 1, -L-STF symbol 1, +L-STF symbol 1, +L-STF symbol 1, -L-STF symbol 1, +L-STF symbol 1, +L-STF symbol 1, +L-STF symbol 1, -L-STF symbol 1, -L-STF symbol 1, -L-STF symbol 1, +L-STF symbol 2, -L-STF symbol 2, +L-STF symbol 2, +L-STF symbol 2, -L-STF symbol 2, +L-STF symbol 2, +L-STF symbol 2, +L-STF symbol 2, -L-STF symbol 2, -L-STF symbol 2, -L-STF symbol 2}. Alternatively, the first STF may include {+L-STF symbol 1, -L-STF symbol 2, +L-STF symbol 1, +L-STF symbol 2, -L-STF symbol 1, +L-STF symbol 2, +L-STF symbol 1, +L-STF symbol 2, -L-STF symbol 1, -L-STF symbol 2, -L-STF symbol 1, +L-STF symbol 2, -L-STF symbol 1, +L-STF symbol 2, +L-STF symbol 1, -L-STF symbol 2, +L-STF symbol 1, +L-STF symbol 2, +L-STF symbol 1, -L-STF symbol 2, -L-STF symbol 1, -L-STF symbol 2}.The L-STF symbol 1 shown here may be understood as the first OFDM symbol among the two OFDM symbols occupied by the L-STF, and it can be understood that the L-STF symbol 2 may be understood as the second OFDM symbol among the two OFDM symbols occupied by the L-STF.

[0154] When a multiple greater than 13 needs to be extended, multiple groups of Barker codes may be extended. For example, it should be noted that three groups of 13-bit Barker codes are extended, that is, this corresponds to extending 39 times. Each loop may be further multiplied by +1 or -1. For example, when three groups of 13-bit Barker codes are extended, the first group may use a 13-bit Barker code, the second group may use a 13-bit Barker code, and the third group may use a sequence obtained by negating the entire 13-bit Barker code. In another example, when three groups of 13-bit Barker codes are extended, the first group may use a 13-bit Barker code, the second group may use a sequence obtained by negating the entire 13-bit Barker code, and the third group may use a 13-bit Barker code. Alternatively, three symbols may be packed, and then the 13-bit Barker code is extended. The packed symbols of each group may be further multiplied by +1 or -1. Examples are not enumerated here. Alternatively, 2x or 4x symbols may be directly extended. Compared with 1x symbols, this is equivalent to the 2x or 4x symbols being extended 2 or 4 times more. It can be understood that the description of extending a multiple greater than 13 shown here is also applicable to the following solution of extending a part of the OFDM symbol. Details are not described below.

[0155] In other possible implementation manners, it can also be understood as follows that the first STF is obtained by extending a part of the OFDM symbols in the second STF by using the first sequence. The first STF is obtained by extending a part of the OFDM symbols occupied by the second STF by using the first sequence. For example, one OFDM symbol may include N periodic parts, where N is a positive integer. In this case, the first STF may be obtained by extending M periodic parts in the second STF by using the first sequence, where M is an integer greater than 1 and less than N. For example, if an OFDM symbol with a period of 0.8 microseconds is used and the time length of one symbol is 4 microseconds, that is, N = 5, the transmitting end may perform the extension based on the part with a period of 0.8 microseconds. For example, the extension may be performed at a period of 0.8 microseconds in one OFDM symbol (that is, M = 1). For example, if an OFDM symbol with a period of 1.6 microseconds is used and the time length of one symbol is 8 microseconds, the transmitting end may perform the extension based on the part with a period of 1.6 microseconds. For example, the extension may be performed at a period of 1.6 microseconds in one OFDM symbol. When M is equal to N, it can be understood that this indicates that the first STF is obtained by extending the OFDM symbols occupied by the second STF by using the first sequence.

[0156] For example, a Barker code with a length of 11 is used as an example. In this case, the first STF is {the first part within the +HE-STF symbol, the first part within the -HE-STF symbol, the first part within the +HE-STF symbol, the first part within the +HE-STF symbol, the first part within the -HE-STF symbol, the first part within the +HE-STF symbol, the first part within the +HE-STF symbol, the first part within the +HE-STF symbol, the first part within the -HE-STF symbol, the first part within the -HE-STF symbol, the first part within the -HE-STF symbol; the second part within the +HE-STF symbol, the second part within the -HE-STF symbol, the second part within the +HE-STF symbol, the second part within the +HE-STF symbol, the second part within the -HE-STF symbol, the second part within the +HE-STF symbol, the second part within the +HE-STF symbol, the second part within the +HE-STF symbol, the second part within the -HE-STF symbol, the second part within the -HE-STF symbol, the second part within the -HE-STF symbol; the third part within the +HE-STF symbol, the third part within the -HE-STF symbol, the third part within the +HE-STF symbol, the third part within the +HE-STF symbol, the third part within the -HE-STF symbol, the third part within the +HE-STF symbol, the third part within the +HE-STF symbol, the third part within the +HE-STF symbol, the third part within the -HE-STF symbol, the third part within the -HE-STF symbol, the third part within the -HE-STF symbol, the fourth part within the +HE-STF symbol; the fourth part within the -HE-STF symbol, the fourth part within the +HE-STF symbol, the fourth part within the +HE-STF symbol, the fourth part within the -HE-STF symbol, the fourth part within the +HE-STF symbol, the fourth part within the +HE-STF symbol, the fourth part within the +HE-STF symbol, the fourth part within the -HE-STF symbol, the fourth part within the -HE-STF symbol, the fourth part within the -HE-STF symbol;+the fifth part within the HE-STF symbol, -the fifth part within the -HE-STF symbol, +the fifth part within the HE-STF symbol, +the fifth part within the HE-STF symbol, -the fifth part within the -HE-STF symbol, +the fifth part within the HE-STF symbol, +the fifth part within the HE-STF symbol, +the fifth part within the HE-STF symbol, -the fifth part within the -HE-STF symbol, -the fifth part within the -HE-STF symbol, -the fifth part within the -HE-STF symbol} may be included. The first part (or the second part, the third part, the fourth part, or the fifth part) within the HE-STF symbol indicates that the value of each subcarrier within the first part (or the second part, the third part, the fourth part, or the fifth part) within the HE-STF symbol is negated.;

[0157] An example is shown where the first STF shown above is obtained based on the second STF and the first sequence. However, the first STF shown in the embodiments of this application is not necessarily obtained based on the second STF and the first sequence. For example, both communication parties may store the sequence that needs to be carried by the first STF, and then directly add the sequences stored during each communication to the first STF. In other words, the sequence carried by the first STF may be obtained by expanding the first STF, or may be stored in advance. Specifically, in actual applications, the transmitting end may obtain the first STF based on the second STF and the first sequence, or the transmitting end may add the above final result (for example, the sequence included in the first STF shown above) to the first STF without performing the step of obtaining the first STF based on the second STF and the first sequence. The description of the first STF here is also applicable to the first LTF shown below.

[0158] Based on the first STF shown in the embodiments of this application, the receiving end may perform the following processing, that is, performing cross-correlation or auto-correlation on the first STF and may be executed.

[0159] In an embodiment of this application, the receiving end may perform cross-correlation or auto-correlation on the first STF in more STF periods to increase the equivalent signal-to-noise ratio (SNR) (since the signal energy is constant and the noise is random, after superposition is performed on the first STF, the signal energy can be accumulated, but the noise cannot be accumulated. Therefore, the equivalent SNR increases). For example, before extension, the receiving end may perform cross-correlation in four 0.8 microseconds (e.g., one OFDM symbol). After extension, when the second STF is extended based on the Barker code with a length of 11, the receiving end may perform cross-correlation operations in 44 0.8 microseconds. It can be understood that the receiving end may further use more STF periods to perform automatic gain control and coarse time synchronization and coarse frequency synchronization.

[0160] The first STF shown in the embodiment of this application may be understood as an enhanced STF or an extended STF, and can effectively solve the following problems. For example, after the L-STF is transmitted over a sufficiently long range, the receiving end may not accurately identify the L-STF. As a result, when the energy of the L-STF is smaller than the sensitivity of the receiving end, the L-STF is erroneously considered as noise. Therefore, the receiving end can effectively identify the first STF, and the efficiency of detecting the PPDU by the receiving end is improved. It can be understood that the receiving end shown in the embodiment of this application may also be understood as the target receiving end shown above. For the parsing of the first part by the target receiving end, refer to the above description of parsing the PPDU by a third-party device. Details are not described again here. Further, for the description of the third-party device, refer to the above description. Details are not described again here.

[0161] Item 2: The PPDU includes a first LTF, the first LTF is obtained based on a second LTF and a second sequence, and the time length of the first LTF is greater than the time length of the L-LTF.

[0162] The second sequence shown in the embodiments of this application is a sequence used to extend the second LTF, and the second sequence is used to extend the second LTF to obtain the first LTF. That is, the function of the first sequence is an extension. For example, the fact that the first LTF is obtained based on the second LTF and the first sequence can also be understood as follows. The first LTF is obtained based on an OFDM symbol or a part of an OFDM symbol occupied by the second LTF, or the sequence carried by the first LTF (which may also be called the first LTF sequence) is obtained by extending the sequence carried by the second LTF (which may also be called the second LTF sequence).

[0163] For the relationship between the time duration and the OFDM symbol, refer to the relevant description in the first item. Details will not be described again here.

[0164] The second LTF may include any one of L-LTF, EHT-LTF, HE-LTF, VHT-LTF, and HT-LTF (for example, included in the first part of the PPDU). For example, the sequence carried by the first LTF may be obtained based on the second sequence and the sequence carried by the L-LTF (abbreviated as the L-LTF sequence), or the sequence carried by the first LTF may be obtained based on the second sequence and the sequence carried by the EHT-LTF field (abbreviated as the EHT-LTF sequence). Details will not be described again here. It can be understood that the second LTF and the second STF shown in the embodiments of this application may be included in different protocols. For example, the second STF includes the HE-STF, and the second LTF includes the EHT-LTF, or the second STF may include the L-STF, and the second LTF may include the EHT-LTF. Obviously, the second LTF and the second STF may alternatively be included in the same protocol. This is not limited in the embodiments of this application.

[0165] EHT-LTF, HE-LTF, VHT-LTF, and HT-LTF may be understood as LTFs in different protocols in the 802.11 standard. It should be noted that LTFs in different protocols may carry different sequences. Therefore, the second LTF is not limited in the embodiments of this application. The second LTF may be a sequence carried by LTFs in different protocols, an LTF carried in a PPDU before Wi-Fi 8, or an LTF that appears in subsequent protocols. Examples are not enumerated here.

[0166] Optionally, the second sequence may be obtained based on a Barker code. For example, a Barker code of length 2 is {+1, -1} or {+1, +1}. In this case, the second sequence may be {+1, -1} or {+1, +1}, or the second sequence may be {-1, +1} or {-1, -1} (i.e., the second sequence may be obtained by negating the Barker code), or the second sequence may be obtained by circularly shifting the Barker code. Examples are not enumerated here. In other examples, a Barker code of length 3 is {+1, +1, -1}. In this case, the second sequence may be {+1, +1, -1}, or the second sequence may be {-1, -1, +1} (i.e., the second sequence is obtained by negating the Barker code), or the second sequence may be obtained by circularly shifting the Barker code. For example, the second sequence is {+1, -1, +1}, or the second sequence is {-1, +1, +1}. In still other examples, a Barker code of length 4 is {+1, +1, -1, +1} or {+1, +1, +1, -1}. The relationship between the second sequence and the Barker code is not enumerated here. It should be noted that the second sequence shown above is equal to the Barker code, or the second sequence is obtained by circularly shifting the Barker code, or the second sequence is obtained by negating the Barker code, but this is just an example. For example, the second sequence may alternatively be obtained by sorting the Barker code from back to front.

[0167] Optionally, the second sequence may be obtained based on an MLS, or may be obtained based on a ZC sequence, or may be obtained based on a Gray complementary sequence. Optionally, the elements of the second sequence may include +1. For example, the second sequence may be a sequence of all 1s, which can be understood as follows. The first LTF is obtained by simply copying the second LTF.

[0168] It should be noted that the first sequence and the second sequence may be the same, or the first sequence and the second sequence may be different. When the first sequence and the second sequence are the same, since the extended lengths are the same, the implementation is simple. When the first sequence and the second sequence are different, the transmitter may dynamically select the length based on the performance of the receiver to balance the overhead caused by the performance of the receiver and the repetition of the extension. For example, when the performance of the first STF is good, the first STF may be extended several times less than the first LTF. The difference between the first sequence and the second sequence may include at least one of the following. For example, the first sequence and the second sequence have different lengths. In another example, the first sequence is obtained by negating the Barker code sequence, and the second sequence is the Barker code sequence. In still another example, the first sequence is the Barker code sequence, and the second sequence is obtained by negating the Barker code sequence. In still another example, the first sequence is obtained by negating the Barker code sequence, and the second sequence is obtained by circularly shifting the Barker code sequence. In other words, the difference between the first sequence and the second sequence may be that the first sequence and the second sequence are obtained based on different processing methods of the Barker code, or the first sequence and the second sequence have different lengths. The differences shown above include the following. The first sequence and the second sequence have the same length, and the first sequence and the second sequence may be obtained based on different processing methods of the Barker code, or the first sequence and the second sequence have different lengths, and the first sequence and the second sequence are obtained based on different processing methods of the Barker code. It can be understood that the description of the relationship between the first sequence and the second sequence is also applicable to the following descriptions of the first sequence and the fourth sequence, the first sequence and the fifth sequence, the second sequence and the fourth sequence, and the second sequence and the fifth sequence. Details will not be described below.

[0169] The following uses an example in which the first LTF is obtained based on the second LTF and the second sequence, and the second sequence is obtained based on Barker codes to explain the first LTF.

[0170] The OFDM symbol or part of the OFDM symbol occupied by the second LTF modulated through OFDM is extended by using Barker codes to obtain the first LTF, so that the time length of the first LTF becomes larger than the time length of the L-LTF. The above extension method may also be considered as weighted repetition of signals in the time domain. Therefore, the receiving end may perform maximum likelihood synthesis based on the first LTF, thereby improving the equivalent signal-to-noise ratio and ensuring that the receiving end detects the PPDU in a longer range. It can be understood that the related explanations shown here are also applicable to other types of second sequences.

[0171] In a possible implementation manner, it can also be understood as follows that the first LTF is obtained by extending the OFDM symbols in the second LTF by using the second sequence. The first LTF is obtained by extending the OFDM symbols occupied by the second LTF by using the second sequence. When the second sequence is obtained based on the Barker code, it can be understood that the first LTF may also be understood as being obtained based on the Barker code and the OFDM symbols occupied by the second LTF. For example, in addition to the guard interval, the OFDM symbols occupied by the HE-LTF and the EHT-LTF may each be divided into three lengths, namely 1x, 2x, and 4x, which correspond to 3.2 microseconds, 6.4 microseconds, and 12.8 microseconds respectively. The guard interval may be 0.8 microseconds, 1.6 microseconds, or 3.2 microseconds. In other words, one OFDM symbol in the HE-LTF or the EHT-LTF may include any one of the following combinations, namely {3.2 microseconds, 6.4 microseconds, 12.8 microseconds} and any one of {0.8 microseconds, 1.6 microseconds, 3.2 microseconds}. For example, in addition to the guard interval, the time length of the OFDM symbols occupied by the L-LTF, HT-LTF, and VHT-LTF may be 3.2 microseconds. The guard interval of the L-LTF is one 3.2 microseconds shared by two 1.6 microseconds. The guard interval of the HT-LTF is 0.8 microseconds. The guard interval of the VHT-LTF is 0.4 microseconds or 0.8 microseconds. It can be understood that the above lengths of the guard intervals are merely examples. For example, the guard interval may be further increased. Examples are not enumerated here.

[0172] In a 20 MHz bandwidth, the sequence carried by 1x HE-LTF is HELTF -122,122={0,0,-1,0,0,0,+1,0,0,0,+1,0,0,0,-1,0,0,0,+1,0,0,0,-1,0,0,0,+1,0,0,0,+1,0,0,0,+1,0,0,0,+1,0,0,0,-1,0,0,0,-1,0,0,0,+1,0,0,0,+1,0,0,0,+1,0,0,0,-1,0,0,0,-1,0,0,0,-1,0,0,0,+1,0,0,0,-1,0,0,0,-1,0,0,0,+1,0,0,0,+1,0,0,0,-1,0,0,0,-1,0,0,0,+1,0,0,0,-1,0,0,0,-1,0,0,0,+1,0,0,0,-1,0,0,0,0,0,0,0,-1,0,0,0,+1,0,0,0,+1,0,0,0,+1,0,0,0,+1,0,0,0,+1,0,0,0,+1,0,0,0,-1,0,0,0,-1,0,0,0,-1,0,0,0,-1,0,0,0,+1,0,0,0,-1,0,0,0,-1,0,0,0,-1,0,0,0,+1,0,0,0,-1,0,0,0,-1,0,0,0,+1,0,0,0,-1,0,0,0,+1,0,0,0,-1,0,0,0,-1,0,0,0,-1,0,0,0,-1,0,0} is as follows.

[0173] For example, in a 20 MHz bandwidth, the sequence carried by 2xHE-LTF is HELTF -122,122={-1, 0, -1, 0, -1, 0, +1, 0, +1, 0, -1, 0, +1, 0, -1, 0, -1, 0, -1, 0, -1, 0, +1, 0, -1, 0, +1, 0, -1, 0, -1, 0, +1, 0, +1, 0, -1, 0, +1, 0, +1, 0, +1, 0, +1, 0, +1, 0, -1, 0, +1, 0, -1, 0, +1, 0, -1, 0, -1, 0, +1, 0, +1, 0, -1, 0, +1, 0, -1, 0, -1, 0, -1, 0, -1, 0, +1, 0, -1, 0, +1, 0, +1, 0, +1, 0, -1, 0, -1, 0, +1, 0, -1, 0, -1, 0, -1, 0, -1, 0, +1, 0, -1, 0, -1, 0, -1, 0, +1, 0, +1, 0, +1, 0, -1, 0, -1, 0, +1, 0, 0, 0, +1, 0, -1, 0, +1, 0, +1, 0, -1, 0, +1, 0, +1, 0, -1, 0, +1, 0, +1, 0, -1, 0, -1, 0, +1, 0, -1, 0, +1, 0, +1, 0, +1, 0, +1, 0, -1, 0, +1, 0, -1, 0, +1, 0, +1, 0, -1, 0, -1, 0, +1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, +1, 0, -1, 0, +1, 0, +1, 0, -1, 0, -1, 0, +1, 0, +1, 0, -1, 0, +1, 0, -1, 0, -1, 0, -1, 0, -1, 0, +1, 0, -1, 0, +1} is as follows.

[0174] In the 20 MHz bandwidth, the sequence carried by 4xHE-LTF is HELTF -122,122={-1,-1,+1,-1,+1,-1,+1,+1,+1,-1,+1,+1,+1,-1,-1,+1,-1,-1,-1,-1,-1,+1,+1,-1,-1,-1,-1,+1,+1,-1,+1,-1,+1,+1,+1,+1,-1,+1,-1,-1,+1,+1,-1,+1,+1,+1,+1,-1,-1,+1,-1,-1,-1,+1,+1,+1,+1,-1,+1,+1,-1,-1,-1,-1,+1,-1,-1,+1,+1,-1,+1,-1,-1,-1,-1,+1,-1,+1,-1,-1,-1,-1,-1,-1,+1,+1,-1,-1,-1,-1,-1,+1,-1,-1,+1,+1,+1,-1,+1,+1,+1,-1,+1,-1,+1,-1,-1,-1,-1,-1,+1,+1,+1,-1,-1,-1,+1,-1,+1,+1,+1,0,0,0,-1,+1,-1,+1,-1,+1,+1,-1,+1,+1,+1,-1,-1,+1,-1,-1,+1,-1,+1,-1,+1,+1,+1,-1,+1,+1,+1,-1,-1,+1,-1,-1,-1,-1,-1,+1,+1,-1,-1,-1,-1,-1,-1,+1,-1,+1,-1,-1,-1,-1,+1,-1,+1,+1,-1,-1,+1,-1,-1,-1,-1,+1,+1,-1,+1,+1,+1,+1,+1,+1,+1,-1,+1,+1,-1,-1,-1,-1,+1,-1,-1,+1,+1,-1,+1,-1,-1,-1,-1,+1,-1,+1,-1,-1,+1,+1,+1,+1,-1,-1,+1,+1,+1,+1,+1,-1,+1,+1,-1,-1,-1,+1,-1,-1,-1,+1,-1,+1,-1,+1,+1} is as follows.

[0175] For example, a Barker code with a length of 11 is used as an example. In this case, the first LTF may include {+HE-LTF symbol, -HE-LTF symbol, +HE-LTF symbol, +HE-LTF symbol, -HE-LTF symbol, +HE-LTF symbol, +HE-LTF symbol, +HE-LTF symbol, -HE-LTF symbol, -HE-LTF symbol, -HE-LTF symbol}. The -HE-LTF symbol indicates that the value of each subcarrier of the HE-LTF symbol is negated.

[0176] In other possible implementation manners, it can also be understood as follows that the first LTF is obtained by extending a part of the OFDM symbols in the second LTF by using a second sequence. The first LTF is obtained by extending a part of the OFDM symbols occupied by the second LTF by using the second sequence. For example, for a 16-microsecond OFDM symbol (a 3.2-microsecond guard interval and a part of 12.8 microseconds other than the guard interval), the second LTF may be extended based on 3.2 microseconds. The specific manner of extending a part of the OFDM symbols occupied by the second LTF to obtain the first LTF is not enumerated here.

[0177] Based on the first LTF shown in the embodiments of this application, the receiving end may perform the following processing, that is, It may perform maximum likelihood synthesis on the first LTF. For the first LTF, maximum likelihood synthesis may be performed on the symbols occupied by the extended LTF to increase the equivalent SNR for channel estimation. It can be understood that the receiving end may further use more LTF periods to perform channel estimation, fine time synchronization, fine frequency synchronization, etc.

[0178] The first LTF shown in the embodiments of this application may be understood as an enhanced LTF or an extended LTF, and can effectively solve the following problems. For example, after the L-LTF is transmitted over a sufficiently long range, the receiving end may not accurately identify the L-LTF. As a result, when the energy of the L-LTF is smaller than the sensitivity of the receiving end, the L-LTF may be erroneously considered as noise. Therefore, the receiving end can effectively identify the first LTF, and the efficiency of detecting the PPDU by the receiving end is improved. It can be understood that the receiving end shown in the embodiments of this application may also be understood as the target receiving end shown above. For the parsing of the first part by the target receiving end, refer to the above description of parsing the PPDU by a third-party device. Details will not be described again here. For the description of the third-party device, refer to the above description. Details will not be described again here.

[0179] Item 3: The PPDU includes a first SIG field, the time length of the first SIG field is longer than the time length of the L-SIG field, and the first SIG field is obtained based on a fourth sequence and an OFDM symbol generated based on at least one of the following information, namely, service set color, association identifier, cyclic redundancy check, tail bit, and modulation and coding scheme.

[0180] Optionally, the fourth sequence may be obtained based on Barker codes. For example, a Barker code of length 2 is {+1, -1} or {+1, +1}. In this case, the fourth sequence may be {+1, -1} or {+1, +1}, or the fourth sequence may be {-1, +1} or {-1, -1} (i.e., the fourth sequence may be obtained by negating the Barker code), or the fourth sequence may be obtained by circularly shifting the Barker code. Examples are not enumerated here. In other examples, a Barker code of length 3 is {+1, +1, -1}. In this case, the fourth sequence may be {+1, +1, -1}, or the fourth sequence may be {-1, -1, +1} (i.e., the fourth sequence is obtained by negating the Barker code), or the fourth sequence may be obtained by circularly shifting the Barker code. For example, the fourth sequence is {+1, -1, +1}, or the fourth sequence is {-1, +1, +1}. In still other examples, a Barker code of length 4 is {+1, +1, -1, +1} or {+1, +1, +1, -1}. The relationship between the fourth sequence and the Barker code is not enumerated here. It can be understood that the fourth sequence may alternatively be obtained by sorting the Barker code from back to front. Examples are not enumerated here.

[0181] Optionally, the fourth sequence may be obtained based on MLS, or may be obtained based on a ZC sequence, or may be obtained based on a Gray complementary sequence. Optionally, the elements of the fourth sequence may include +1. For example, the fourth sequence may be a sequence of all 1s, which can also be understood as follows. The first SIG field is obtained by simply copying the L-SIG field. For the relationship between the fourth sequence and the first sequence or the relationship between the fourth sequence and the second sequence, refer to the above description of the relationship between the first sequence and the second sequence. Details are not explained again here.

[0182] For example, the first SIG field may use 1x symbols, 52 data subcarriers, BPSK, and 1 / 2 coding rate modulation, and may carry 26 information bits. For example, the first SIG field may carry at least one of the following information, namely, a 5-bit basic service set color used to identify the basic service set where the first SIG field is located, an 11-bit association identifier used to identify the station, a 4-bit cyclic redundancy check used to check the information, and a 6-bit tail bit used to terminate the trellis of the convolutional decoder. For example, the first SIG field may use 2x or 4x symbols to carry more information bits. For example, the first SIG field may carry at least one of the following information, namely, a basic service set color of 6 bits or more used to identify the basic service set where the first SIG field is located, an 11-bit association identifier used to identify the station, a modulation and coding scheme indicating the corresponding modulation and coding scheme and supporting a higher coding rate (or indicating whether dual carrier modulation is used, whether replicated transmission is performed in the frequency domain, etc.), an 8-bit cyclic redundancy check used to check the information, and a 6-bit tail bit used to terminate the trellis of the convolutional decoder. It can be understood that the first U-SIG field shown above may further carry at least one of the following information, namely, the length of the physical layer service data unit (PSDU) (e.g., the number of bytes) or the number of OFDM symbols in the data field. Examples are not enumerated here.

[0183] For example, after generating one or more OFDM symbols based on the above information, the transmitting end may extend the OFDM symbol (e.g., extend the OFDM symbol based on the Barker code) to obtain the first SIG field, so that the time length of the first SIG field is greater than the time length of the L-SIG field. For example, the OFDM symbol is generated based on the above information. A Barker code with a length of 11 is used as an example. In this case, the first SIG field may include {+SIG symbol, -SIG symbol, +SIG symbol, +SIG symbol, -SIG symbol, +SIG symbol, +SIG symbol, +SIG symbol, -SIG symbol, -SIG symbol, -SIG symbol}. The -SIG symbol indicates that the value of each subcarrier of the SIG symbol is negated. The SIG symbol shown here can be understood as an OFDM symbol generated based on the above information. For specific extension methods, refer to the descriptions in the first item and the second item. Details will not be described again here.

[0184] The first SIG field may further use dual-carrier modulation (DCM), or replication transmission may be further performed on the first SIG field in the frequency domain, or the first SIG field may be further transmitted on discrete subcarriers to further improve the reliability of the first SIG field.

[0185] In the embodiments of this application, regarding the indication of the length of the L-SIG field, the time length range indicated by the length field of the L-SIG field may include the range of the acknowledgment frame to protect the reception of the acknowledgment frame. Alternatively, the indication of the length of the L-SIG field may indicate "until the end of the PPDU". The indication method of the length of the L-SIG field is not limited in the embodiments of this application.

[0186] Based on the first SIG field shown in the embodiments of this application, the receiving end performs the following processing, that is, It may be performed to perform maximum likelihood synthesis on the first SIG field. For example, for the first SIG field, maximum likelihood synthesis may be performed on the symbols occupied by the extended SIG field, so that the log-likelihood ratio (LLR) becomes more accurate, the accuracy of demodulating the first SIG field is improved, and the accuracy of demodulating the PPDU is improved. The receiving end may further demodulate the signaling information of subsequent data based on the first SIG field.

[0187] The first SIG field shown in the embodiments of this application can be understood as an enhanced SIG field, an extended SIG field, etc. The SIG field is extended so that the efficiency of detecting the PPDU by the receiving end can be improved and the accuracy of demodulating the PPDU can be improved. It can be understood that the receiving end shown in the embodiments of this application may be understood as the target receiving end shown above. For the parsing of the first part by the target receiving end, refer to the above description of parsing the PPDU by the third-party device. Details are not described again here. For the description of the third-party device, refer to the above description. Details are not described again here.

[0188] Item 4: The PPDU includes a first data field, which is obtained based on a fifth sequence and OFDM symbols generated based on information bits. For the description of the fifth sequence, refer to the above descriptions of the first sequence, the second sequence, and the fourth sequence. Details are not described again here. For example, after generating OFDM symbols based on information bits, the transmitting end may expand the generated one or more OFDM symbols to obtain the first data field. For example, the OFDM symbols (e.g., the Data symbols shown below) are generated based on the above information. A Barker code with a length of 11 is used as an example. In this case, the first data field may include {+Data symbol, -Data symbol, +Data symbol, +Data symbol, -Data symbol, +Data symbol, +Data symbol, +Data symbol, -Data symbol, -Data symbol, -Data symbol}. The -SIG symbol indicates that the value of each subcarrier of the SIG symbol is negated. In another example, two OFDM symbols (e.g., Data symbol 1 and Data symbol 2 shown below) are generated based on the above information. A Barker code with a length of 11 is used as an example. In this case, the first data field may include {+Data symbol 1, -Data symbol 1, +Data symbol 1, +Data symbol 1, -Data symbol 1, +Data symbol 1, +Data symbol 1, +Data symbol 1, -Data symbol 1, -Data symbol 1, -Data symbol 1, +Data symbol 2, -Data symbol 2, +Data symbol 2, +Data symbol 2, -Data symbol 2, +Data symbol 2, +Data symbol 2, +Data symbol 2, -Data symbol 2, -Data symbol 2, -Data symbol 2}. For the specific expansion method, refer to the descriptions in Item 1 and Item 2. Details are not described again here.

[0189] The data field is extended by using a Barker code, so that the reliability of the first data field can be improved. It can be understood that the Barker code shown here is merely an example. For example, the first data field may be obtained based on an MLS and an OFDM symbol generated based on information bits, or may be obtained based on a ZC sequence and an OFDM symbol generated based on information bits, or may be obtained based on a Gray complementary sequence and an OFDM symbol generated based on information bits, or may be obtained based on a sequence of all 1s and an OFDM symbol generated based on information bits.

[0190] In an embodiment of this application, the first data field may also further use a DCM, or duplicate transmission may be further performed on the first data field in the frequency domain, or the first data field may be further transmitted on discrete subcarriers to further improve the reliability of the first data field.

[0191] Based on the first data field shown in the embodiment of this application, the receiving end may perform the following processing, that is, perform maximum likelihood synthesis on the first data field. For example, for the first SIG field, maximum likelihood synthesis may be performed on all symbols in the extended SIG field, so that the LLR becomes more accurate and the accuracy of demodulating the first data field by the receiving end is improved. It can be understood that the receiving end shown in the embodiment of this application may be understood as the target receiving end shown above. For the parsing of the first part by the target receiving end, refer to the above description of parsing the PPDU by a third-party device. Details will not be described again here. For the description of the third-party device, refer to the above description. Details will not be described again here.

[0192] Item 5: The PPDU includes a packet extension field that is used to help the receiving end obtain more processing time. Generally, the packet extension field may not carry relevant information, and the receiving end does not need to demodulate the packet extension field. Thus, at this time, the receiving end may continue to demodulate the previously incomplete part. It can be understood that the receiving end shown in the embodiments of this application may be understood as the target receiving end shown above. For the parsing of the first part by the target receiving end, refer to the above description of parsing the PPDU by a third-party device. Details are not described again here. For the description of the third-party device, refer to the above description. Details are not described again here.

[0193] Based on the PPDU shown in the embodiments of this application, fields such as the STF, LTF, and SIG fields are extended based on a sequence such as a Barker code to increase the coverage area of the PPDU. Furthermore, performing the extension based on an OFDM symbol or a part of an OFDM symbol may retain various operations and advantages based on the OFDM symbol.

[0194] Referring to the first item to the fifth item shown above, FIG. 5 is a diagram of the structure of a PPDU according to an embodiment of this application. As shown in FIG. 5, the PPDU may include a second part. Optionally, the PPDU may further include a first part. The second part may include a first STF, a first LTF, a first SIG field, a first data field, and a packet extension field. The time length of the first STF may be 4*n1 microseconds, 8*n1 microseconds, or 16*n1 microseconds, where n1 may be an integer greater than 2. The time length of the first LTF may be 4*n2 microseconds, 8*n2 microseconds, or 16*n2 microseconds, where n2 may be an integer greater than 2. The time length of the first SIG field may be 4*n3 microseconds, 8*n3 microseconds, or 16*n3 microseconds, where n3 may be an integer greater than 1. The time length of the first data field may be 4*n4 microseconds, 8*n4 microseconds, or 16*n4 microseconds, where n4 may be an integer greater than 1. The time length of the packet extension field may be 4*n5, where n5 may be an integer greater than 1. It can be understood that the 4, 8, or 16 shown above may be determined based on the time length of one OFDM symbol.

[0195] For example, the PPDU is an extended range PPDU, the first STF is an extended STF, the first LTF is an extended LTF, the first SIG field is an extended SIG field, and the first data field is an extended data field. FIGS. 6a to 6c are diagrams of the structure of the PPDU according to an embodiment of this application. As shown in FIGS. 6a to 6c, the PPDU may include a non-extended range portion and an extended range portion. For the description of the non-extended range portion, refer to the above description in FIGS. 3a to 3c. For the description of the extended range portion, refer to the above description of the first to fifth items. Optionally, as shown in FIG. 6a, the bandwidth of the non-extended range portion may be the same as the bandwidth of the extended range portion. Optionally, as shown in FIG. 6b, the bandwidth of the non-extended range portion may be smaller than the bandwidth of the extended range portion. Optionally, as shown in FIG. 6c, the extended range portion may be repeatedly transmitted in the frequency domain. Therefore, when the power spectral density is not limited, by reducing the transmission bandwidth of the second portion of the PPDU and increasing the power spectral density, the transmission distance of the second portion can be effectively increased, thereby increasing the coverage area of the Wi-Fi signal.

[0196] FIGS. 7a to 7c are diagrams of the structure of the PPDU according to an embodiment of this application. As shown from FIGS. 7a to 7c, the PPDU may include a non-extended range portion and an extended range portion. For the description of the non-extended range portion, refer to the above description in FIGS. 4a to 4c. For the description of the extended range portion, refer to the above description of the first to fifth items. Optionally, as shown in FIG. 7a, the bandwidth of the non-extended range portion may be the same as the bandwidth of the extended range portion. Optionally, as shown in FIG. 7b, the bandwidth of the non-extended range portion may be smaller than the bandwidth of the extended range portion. Optionally, as shown in FIG. 7c, the extended range portion may be repeatedly transmitted in the frequency domain.

[0197] Based on the PPDU shown in the embodiments of this application, the coverage area of the Wi-Fi signal is further extended based on the coverage area of 802.11b, and the interference prevention ability of the Wi-Fi signal increases (for example, when a part of the signal is interfered and the other part of the signal is not interfered, the receiving end can still accurately receive the non-interfered part). Further, the PPDU shown in the embodiments of this application is further backward compatible, and the preamble part (for example, the first part shown above) can be understood by legacy devices.

[0198] In the implementation method shown above, for parts not described in detail in the implementation method, refer to other implementation methods. The above implementation methods may be separate embodiments, or a plurality of implementation methods may be combined in one embodiment.

[0199] The communication device provided in the embodiments of this application will be described below.

[0200] In this application, the communication device is divided into functional modules based on the embodiments of the above method. For example, each functional module may be divided into its corresponding functions, or two or more functions may be integrated into one processing module. The integrated module may be realized in the form of hardware or in the form of a software functional module. It should be noted that the division into modules in this application is only an example and is merely a logical function division. In the actual implementation method, other division methods may be used. The communication device in the embodiments of this application will be described in detail below with reference to FIGS. 8 to 11.

[0201] FIG. 8 is a structural diagram of a communication device according to an embodiment of the present invention. As shown in FIG. 8, the communication device includes a processing unit 801 and a transceiver unit 802.

[0202] In some embodiments of this application, the communication device may be the transmitting end or chip shown above, and the chip may be disposed at the transmitting end. In other words, the communication device may be configured to execute the steps or functions performed by the transmitting end in the method embodiments.

[0203] The processing unit 801 is configured to generate a PPDU, and the transceiver unit 802 is configured to output the PPDU.

[0204] It can be understood that the specific descriptions of the transceiver unit and processing unit described in this embodiment of this application are merely examples. For the specific functions, steps, etc. of the transceiver unit and processing unit, refer to the method embodiments above. Details are not described here. For example, the processing unit 801 may be configured to execute step 201 shown in FIG. 2, and the transceiver unit 802 may be configured to execute the transmission step in step 202 shown in FIG. 2.

[0205] FIG. 8 is reused. In some embodiments of this application, the communication device may be the receiving end or chip shown above, and the chip may be disposed at the receiving end. In other words, the communication device may be configured to execute the steps or functions performed by the receiving end in the method embodiments.

[0206] For example, the transceiver unit 802 is configured to input a PPDU, and the processing unit 801 is configured to process the PPDU.

[0207] For example, the processing unit 801 may be configured to execute at least one of the following, namely, perform channel estimation based on the PPDU, or perform time synchronization based on the PPDU, or perform related processing based on the PPDU, or perform maximum likelihood synthesis based on the PPDU.

[0208] It can be understood that the specific descriptions of the transceiver unit and the processing unit described in this embodiment of this application are merely examples. For the specific functions, steps, etc. of the transceiver unit and the processing unit, refer to the embodiments of the above method. Details are not described here. For example, the transceiver unit 802 may be further configured to execute the receiving step in step 202 shown in FIG. 2, and the processing unit 801 may be further configured to execute step 203 shown in FIG. 2.

[0209] In the above embodiments, for the descriptions of the PPDU, the first sequence, the second sequence, the third sequence, the fourth sequence, the fifth sequence, etc., refer to the descriptions in the embodiments of the above method. Details are not described again here.

[0210] It can be understood that the above splitting method is merely an example. The splitting methods of the transmitting end (or the chip arranged at the transmitting end) and the receiving end (or the chip arranged at the receiving end) may be further shown as follows. The transmitting end may include a generating unit and a transmitting unit, the receiving end may include a receiving unit and a processing unit, and the processing unit may include at least one of a channel estimation sub-unit, a time synchronization sub-unit, a correlation processing sub-unit, and a maximum likelihood synthesis sub-unit. Examples are not enumerated here. Optionally, each of the transmitting end and the receiving end shown above may further include a storage unit. The storage unit may be configured to store at least one of the first sequence, the second sequence, the third sequence, the fourth sequence, and the fifth sequence shown above. Alternatively, the storage unit may be configured to store at least one of the sequence carried by the first STF (i.e., the final result of the first STF obtained based on the second STF and the first sequence) and the sequence carried by the first LTF (i.e., the final result of the first LTF obtained based on the second LTF and the second sequence).

[0211] The first communication device and the second communication device in the embodiments of this application have been described above. Below, possible product forms of the first communication device and the second communication device will be described. It should be understood that any product form having the functions of the first communication device in FIG. 8 or any product form having the functions of the second communication device in FIG. 8 falls within the protection scope of the embodiments of this application. It should be further understood that the following description is merely an example, and the product forms of the first communication device and the second communication device in the embodiments of this application are not limited thereto.

[0212] In a possible implementation manner, in the communication device shown in FIG. 8, the processing unit 801 may be one or more processors, the transceiver unit 802 may be a transceiver, or the transceiver unit 802 may be a transmission unit and a reception unit. The transmission unit may be a transmitter, the reception unit may be a receiver, and the transmission unit and the reception unit are integrated into one device, for example, a transceiver. In the embodiments of this application, the combination of the processor and the transceiver may be performed, etc. The manner of connecting the processor and the transceiver is not limited in the embodiments of this application.

[0213] As shown in FIG. 9, the communication device 90 includes one or more processors 920 and a transceiver 910.

[0214] For example, when the communication device is configured to execute steps, methods, or functions executed by a transmitting end, the processor 920 is configured to generate a PPDU, and the transceiver 910 is configured to transmit the PPDU.

[0215] For example, when the communication device is configured to execute steps, methods, or functions executed by a receiving end, the transceiver 910 is configured to receive a PPDU from the transmitting end, and the processor 920 is configured to execute processing based on M sequences carried in the PPDU.

[0216] In the embodiments of this application, for the descriptions of PPDU, the first sequence, the second sequence, the third sequence, the fourth sequence, the fifth sequence, etc., refer to the descriptions in the embodiments of the above method. Details are not described again here.

[0217] For the specific descriptions of the processor and the transceiver, it can be understood that reference is made to the descriptions of the processing unit and the transceiver unit shown in FIG. 8. Details are not described again here.

[0218] In each implementation manner of the communication device shown in FIG. 9, the transceiver may include a receiver and a transmitter. The receiver is configured to execute a receiving function (or operation), and the transmitter is configured to execute a transmitting function (or operation). Further, the transceiver is configured to communicate with other devices / apparatuses through a transmission medium.

[0219] Optionally, the communication device 90 may further include one or more memories 930 configured to store program instructions, data, and / or the like. The memory 930 is coupled to the processor 920. The coupling in the embodiments of this application may be an indirect coupling or a communication connection between devices, units, or modules in an electrical form, a mechanical form, or other forms, and is used for information exchange between devices, units, or modules. The processor 920 may operate in cooperation with the memory 930. The processor 920 may execute the program instructions stored in the memory 930. Optionally, at least one of the one or more memories may be included in the processor. For example, the memory may be configured to store at least one of the first sequence, the second sequence, the third sequence, the fourth sequence, and the fifth sequence shown above. For example, the memory may be configured to store at least one of the sequence carried by the first STF (i.e., the final result of the first STF obtained based on the second STF and the first sequence) and the sequence carried by the first LTF (i.e., the final result of the first LTF obtained based on the second LTF and the second sequence).

[0220] In the embodiments of this application, the specific connection medium between the transceiver 910, the processor 920, and the memory 930 is not limited. In the embodiments of this application, in FIG. 9, the memory 930, the processor 920, and the transceiver 910 are connected to each other through a bus 940. In FIG. 9, the bus is represented by using a thick line. The method of connection between other components is only schematically described and is not used as a limitation. The bus may be classified into an address bus, a data bus, a control bus, etc. For the sake of simplicity of expression, only one thick line is used to represent the bus in FIG. 9, but this does not mean that only one bus or only one type of bus exists.

[0221] In the embodiments of this application, the processor may be a general-purpose processor, a digital signal processor, an application-specific integrated circuit, a field-programmable gate array, or other programmable logic device, a discrete gate, or a transistor logic device, a discrete hardware component, etc. The processor can implement or execute the methods, steps, and logical block diagrams disclosed in the embodiments of this application. The general-purpose processor may be a microprocessor or any conventional processor, etc. The steps of the method disclosed in combination with the embodiments of this application may be directly implemented by a hardware processor, or may be implemented by using a combination of a hardware module and a software module in the processor, etc.

[0222] In an embodiment of this application, the memory may include, but is not limited to, a hard disk drive (HDD) or a solid-state drive (SSD), a random access memory (RAM), an erasable programmable read-only memory (EPROM), a read-only memory (ROM), or a portable read-only memory (Compact Disc Read-Only Memory, CD-ROM). The memory is any storage medium that can be used to carry or store program code in the form of instructions or data structures and can be read and / or written by a computer (e.g., the communication device shown in this application). However, this application is not limited thereto. The memory in the embodiments of this application may alternatively be a circuit or any other device configured to implement a storage function and store program instructions and / or data.

[0223] For example, the processor 920 is mainly configured to process communication protocols and communication data, control the entire communication device, execute software programs, and process data of software programs. The memory 930 is mainly configured to store software programs and data. The transceiver 910 may include a control circuit and an antenna. The control circuit is mainly configured to perform conversion between a baseband signal and a radio frequency signal and process the radio frequency signal. The antenna is mainly configured to receive / transmit a radio frequency signal in the form of an electromagnetic wave. An input / output device such as a touch screen, a display, or a keyboard is mainly configured to receive data input by a user and output data to the user.

[0224] After the power supply of the communication device is turned on, the processor 920 may read a software program in the memory 930, interpret and execute the instructions of the software program, and process the data of the software program. When data needs to be transmitted wirelessly, the processor 920 performs baseband processing on the data to be transmitted, and then outputs the baseband signal to the radio frequency circuit. The radio frequency circuit performs radio frequency processing on the baseband signal, and then transmits the radio frequency signal in the form of electromagnetic waves through the antenna. When data is transmitted to the communication device, the radio frequency circuit receives the radio frequency signal through the antenna, converts the radio frequency signal into a baseband signal, and outputs the baseband signal to the processor 920. The processor 920 converts the baseband signal into data and processes the data.

[0225] In other implementation manners, the radio frequency circuit and the antenna may be arranged independently of the processor that performs baseband processing. For example, in a distributed scenario, the radio frequency circuit and the antenna may be arranged remotely and independently of the communication device.

[0226] It can be understood that the communication device shown in the embodiments of this application may further have more components etc. than those in the components etc. in FIG. 9. This is not limited in the embodiments of this application. The method executed by the processor and the transceiver is merely an example. For the specific steps executed by the processor and the transceiver, refer to the above method.

[0227] In other possible implementation manners, in the communication device shown in FIG. 8, the processing unit 801 may be one or more logic circuits. The transceiver unit 802 may be an input / output interface that is also referred to as a communication interface, an interface circuit, an interface, etc. Alternatively, the transceiver unit 802 may be a transmission unit and a reception unit. The transmission unit may be an output interface, and the reception unit may be an input interface. The transmission unit and the reception unit are integrated into one unit, for example, an input / output interface. As shown in FIG. 10, the communication device shown in FIG. 10 includes a logic circuit 1001 and an interface 1002. That is, the processing unit 801 may be implemented via the logic circuit 1001, and the transceiver unit 802 may be implemented via the interface 1002. The logic circuit 1001 may be a chip, a processing circuit, an integrated circuit, a system on chip (SoC), etc. The interface 1002 may be a communication interface, an input / output interface, a pin, etc. FIG. 10 shows an example where the communication device is a chip. The chip includes a logic circuit 1001 and an interface 1002.

[0228] In this embodiment of this application, the logic circuit and the interface may be coupled to each other. The specific manner of connection between the logic circuit and the interface is not limited in the embodiments of this application.

[0229] For example, when the communication device is configured to execute a method, function, or step performed by a transmitting end, the logic circuit 1001 is configured to generate a PPDU, and the interface 1002 is configured to output the PPDU.

[0230] For example, when the communication device is configured to execute a method function or step performed by a receiving end, the interface 1002 is configured to input a PPDU, and the logic circuit 1001 is configured to process the PPDU.

[0231] Optionally, the chip may further include memory. The memory may be configured to store at least one of the first sequence, the second sequence, the third sequence, the fourth sequence, and the fifth sequence shown above. For example, the memory may be configured to store at least one of the following, namely, the sequence carried by the first STF (i.e., the final result of the first STF obtained based on the second STF and the first sequence), and the sequence carried by the first LTF (i.e., the final result of the first LTF obtained based on the second LTF and the second sequence). Obviously, the memory may be further disposed outside the chip. For example, the chip may obtain the first sequence to the fifth sequence from the memory connected to the chip, or may obtain the sequence carried by the first STF and / or the sequence carried by the first LTF.

[0232] It can be understood that the communication device shown in the embodiments of this application may implement the method provided in the embodiments of this application in the form of hardware, or may implement the method provided in the embodiments of this application in the form of software. This is not limited in the embodiments of this application.

[0233] In the embodiments of this application, for the description of PPDU, the first sequence, the second sequence, the third sequence, the fourth sequence, the fifth sequence, etc., refer to the description in the embodiments of the above method. Details are not described again here.

[0234] For the specific implementation manner of the embodiment shown in FIG. 10, refer to the above embodiments. Details are not described again here.

[0235] Embodiments of this application further provide a wireless communication system. The wireless communication system includes a transmitting end and a receiving end. The transmitting end and the receiving end may be configured to execute the method in any one of the above embodiments (as shown in FIG. 2). FIG. 11 is a diagram of the structure of a communication system according to an embodiment of this application. The communication system includes AP101 and STA103. It can be understood that the transmitting end shown above may be an AP or an STA, and the receiving end may also be an AP or an STA.

[0236] STA103 includes at least one processor (an example in which STA103 includes one processor 301 is used for the description in FIG. 11) and at least one transceiver (an example in which STA103 includes one transceiver 303 is used for the description in FIG. 11). Optionally, STA103 may further include at least one memory (an example in which STA103 includes one memory 302 is used for the description in FIG. 11), at least one output device (an example in which STA103 includes one output device 304 is used for the description in FIG. 11), and at least one input device (an example in which STA103 includes one input device 305 is used for the description in FIG. 11). The processor 301, the memory 302, and the transceiver 303 are connected through a communication line. The communication line may include a path for transmitting information among the above components. For the related descriptions of the processor, the memory, and the transceiver, refer to the above description. Details are not described again here.

[0237] For example, the memory 302 is configured to store computer-executable instructions for executing the solutions in this application, and the processor 301 controls the execution. Specifically, the processor 301 is configured to execute the computer-executable instructions stored in the memory 302 to implement the communication method based on the PPDU in the embodiments of this application.

[0238] AP101 includes at least one processor (an example where AP101 includes one processor 201 is used for the description in FIG. 11), at least one transceiver (an example where AP101 includes one transceiver 203 is used for the description in FIG. 11), and at least one network interface (an example where AP101 includes one network interface 204 is used for the description in FIG. 11). Optionally, AP101 may further include at least one memory (an example where AP101 includes one memory 202 is used for the description in FIG. 11). The processor 201, the memory 202, the transceiver 203, and the network interface 204 are connected through communication lines. The network interface 204 is connected to a core network device through a link (e.g., S1 interface), or is configured to be connected to the network interface of another AP through a wired or wireless link (e.g., X2 interface) (not shown in FIG. 11). This is not particularly limited in the embodiments of this application. For the related descriptions of the processor, the memory, and the transceiver, refer to the above description. Details will not be described again here.

[0239] For example, the memory may be configured to store at least one of the first sequence, the second sequence, the third sequence, the fourth sequence, and the fifth sequence shown above. For example, the memory may be configured to store at least one of the following, namely, the sequence carried by the first STF (i.e., the final result of the first STF obtained based on the second STF and the first sequence), and the sequence carried by the first LTF (i.e., the final result of the first LTF obtained based on the second LTF and the second sequence). Obviously, the memory may be further disposed outside the chip. For example, the chip may obtain the first sequence to the fifth sequence from a memory connected to the chip, or may obtain the sequence carried by the first STF and / or the sequence carried by the first LTF.

[0240] It can be understood that the structure shown in FIG. 11 does not constitute specific limitations on the AP and STA. For example, in some other embodiments of this application, STA 103 may include more or fewer components than those shown in the drawings, some components may be combined, some components may be divided, or the components may be arranged differently. The components shown in the drawings may be implemented by hardware, software, or a combination of software and hardware.

[0241] Furthermore, this application further provides a computer program. The computer program is used to implement the operations and / or processes executed by the transmitting end in the method provided in this application.

[0242] This application further provides a computer program. The computer program is used to implement the operations and / or processes executed by the receiving end in the method provided in this application.

[0243] This application further provides a computer-readable storage medium. The computer-readable storage medium stores computer code. When the computer code is executed on a computer, the computer can execute the operations and / or processes executed by the transmitting end in the method provided in this application.

[0244] This application further provides a computer-readable storage medium. The computer-readable storage medium stores computer code. When the computer code is executed on a computer, the computer can execute the operations and / or processes executed by the receiving end in the method provided in this application.

[0245] This application further provides a computer program product. The computer program product includes computer code or a computer program. When the computer code or the computer program is executed on a computer, the operations and / or processes executed by the transmitting end in the method provided in this application are executed.

[0246] This application further provides a computer program product. The computer program product includes computer code or a computer program. When the computer code or the computer program is executed on a computer, the operations and / or processes executed by the receiving end in the method provided in this application are executed.

[0247] In some embodiments provided in this application, it should be understood that the disclosed systems, devices, and methods may be implemented in other ways. For example, the described device embodiments are merely examples. For example, the division into units is merely a logical function division, and other divisions may be used in actual implementation. For example, a plurality of units or components may be combined or integrated into other systems, or some features may be ignored or not executed. Furthermore, the described mutual coupling, direct coupling, or communication connection may be realized through some interfaces. The indirect coupling or communication connection between devices or units may be realized in electronic, mechanical, or other forms.

[0248] The units described as separate parts may or may not be physically separate, and the parts shown as units may or may not be physical units. They may be located in one place or distributed among multiple network units. Some or all of the units may be selected based on the actual requirements for realizing the technical effects of the solutions provided in the embodiments of this application.

[0249] Furthermore, the functional units in the embodiments of this application may be integrated into one processing unit, each of the units may physically exist independently, or two or more units may be integrated into one unit. The integrated unit may be implemented in the form of hardware or in the form of a software functional unit.

[0250] When the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, the integrated unit may be stored in a computer-readable storage medium. Based on such understanding, the technical solution of this application is essentially, or the part that contributes to the prior art or all or part of the technical solution may also be implemented in the form of a software product. The computer software product is stored in a readable storage medium and includes several instructions for instructing a computer device (which may be a personal computer, a server, a network device, etc.) to execute all or part of the steps of the method described in the embodiments of this application. The readable storage medium includes any medium that can store program codes, such as a USB flash drive, a removable hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0251] The above description is merely a specific implementation manner of this application and is not intended to limit the protection scope of this application. Any deformation or substitution that can be easily conceived by those skilled in the art within the technical scope disclosed in this application shall fall within the protection scope of this application. Therefore, the protection scope of this application shall be subject to the protection scope of the claims.

Claims

Claim 1 A communication method based on a physical layer protocol data unit (PPDU), comprising: generating the PPDU, wherein the PPDU includes a legacy short training field (L-STF), a legacy long training field (L-LTF), a legacy signal (L-SIG) field, and a first STF, the first STF is obtained based on a second STF and a first sequence, and a time length of the first STF is greater than a time length of the L-STF; transmitting the PPDU. The method as described above. Claim 2 A communication method based on a physical layer protocol data unit (PPDU), comprising: receiving the PPDU, wherein the PPDU includes a legacy short training field (L-STF), a legacy long training field (L-LTF), a legacy signal (L-SIG) field, and a first STF, the first STF is obtained based on a second STF and a first sequence, and a time length of the first STF is greater than a time length of the L-STF; processing the PPDU. The method as described above. Claim 3 The obtaining of the first STF based on a second STF and a first sequence includes: the first STF is obtained based on the L-STF and the first sequence, or the first STF is obtained based on an extremely high throughput (EHT)-STF and the first sequence, or the first STF is obtained based on a high efficiency (HE)-STF and the first sequence. The method according to claim 1 or 2. Claim 4 The obtaining of the first STF based on the L-STF and the first sequence includes: the first STF is obtained by extending an orthogonal frequency division multiplexing (OFDM) symbol in the L-STF by using the first sequence, or the first STF is obtained by extending a part of the OFDM symbols in the L-STF by using the first sequence. The method according to claim 3. Claim 5 The PPDU further includes a first LTF, and the first LTF is obtained based on a second LTF and a second sequence, and a time length of the first LTF is greater than a time length of the L-LTF. The method according to any one of claims 1 to 4.

6. The fact that the first LTF is obtained based on a second LTF and a second sequence means that the first LTF is obtained by extending OFDM symbols in the second LTF by using the second sequence, or the first LTF is obtained by extending a part of OFDM symbols in the second LTF by using the second sequence The method according to claim 5, including.

7. The PPDU further includes a first SIG field, a time length of the first SIG field is greater than a time length of the L-SIG field, and the first SIG field is obtained based on a fourth sequence and an OFDM symbol generated based on at least one of the following information, that is, a service set color, an association identifier, a cyclic redundancy check, a tail bit, and a modulation and coding scheme. The method according to any one of claims 1 to 6.

8. The PPDU further includes a first data field, and the first data field is obtained based on a fifth sequence and an OFDM symbol generated based on information bits. The method according to any one of claims 1 to 7.

9. The first sequence is obtained based on a Barker code, and / or the second sequence is obtained based on a Barker code. The method according to any one of claims 5 to 8.

10. The PPDU further includes a first binary phase shift keying (BPSK) mark field and a second BPSK mark field. The first BPSK mark field or the second BPSK mark field is the same as the L-SIG field, or The first BPSK mark field or the second BPSK mark field is obtained based on the L-SIG field and a third sequence. The method according to any one of claims 1 to 9.

11. Elements in the third sequence include -1 and +1. The method according to claim 10.

12. The method according to any one of claims 1 to 11, wherein the PPDU further includes at least one of a Repeated Legacy Signal (RL-SIG) field or a Universal Signal (U-SIG) field.

13. The U-SIG field includes the following information, namely, including at least one of the physical layer version of the PPDU and the format of the PPDU, the version number of the physical layer version of the PPDU is greater than 0, The method according to claim 11, wherein the format of the PPDU indicates that the format of the PPDU is an Extended Range PPDU format.

14. The method according to any one of claims 8 to 13, wherein the L-STF, the L-LTF, and the L-SIG fields are included in a first part of the PPDU, the first STF, the first LTF, and the first SIG fields are included in a second part of the PPDU, and the bandwidth of the first part is greater than the bandwidth of the second part.

15. The step of processing the PPDU includes the following, namely, executing cross-correlation or auto-correlation on the first STF, and executing maximum likelihood synthesis on at least one of the first LTF, the first SIG field, and the first data field The method according to any one of claims 8 to 14, including at least one of them.

16. A communication device, a processing unit configured to generate a Physical Layer Protocol Data Unit (PPDU), the PPDU including a Legacy Short Training Field (L-STF), a Legacy Long Training Field (L-LTF), a Legacy Signal (L-SIG) field, and a first STF, the first STF being obtained based on a second STF and a first sequence, and the time duration of the first STF being greater than the time duration of the L-STF, the processing unit; and a transceiver unit configured to transmit the PPDU An apparatus including.

17. A communication device, A transceiver unit configured to receive a physical layer protocol data unit (PPDU), the PPDU including a legacy short training field (L-STF), a legacy long training field (L-LTF), a legacy signal (L-SIG) field, and a first STF, the first STF being obtained based on a second STF and a first sequence, and a time length of the first STF being greater than a time length of the L-STF, and the transceiver unit, A processing unit configured to process the PPDU An apparatus including the above.

18. The fact that the first STF is obtained based on a second STF and a first sequence means that The first STF is obtained based on the L-STF and the first sequence, or The first STF is obtained based on an extremely high throughput (EHT)-STF and the first sequence, or The first STF is obtained based on a high efficiency (HE)-STF and the first sequence The apparatus according to claim 16 or 17, including the above.

19. The fact that the first STF is obtained based on the L-STF and the first sequence means that The first STF is obtained by extending orthogonal frequency division multiplexing (OFDM) symbols in the L-STF by using the first sequence, or The first STF is obtained by extending a part of the OFDM symbols in the L-STF by using the first sequence The apparatus according to claim 18, including the above.

20. The PPDU further includes a first LTF, the first LTF being obtained based on a second LTF and a second sequence, and a time length of the first LTF being greater than a time length of the L-LTF. The apparatus according to any one of claims 16 to 19.

21. The fact that the first LTF is obtained based on a second LTF and a second sequence means that The first LTF is obtained by extending OFDM symbols in the second LTF by using the second sequence, or The first LTF is obtained by extending a part of the OFDM symbols in the second LTF by using the second sequence The apparatus according to claim 20, including the above.

22. The PPDU further includes a first SIG field, the time duration of the first SIG field is greater than the time duration of the L-SIG field, and the first SIG field is obtained based on a fourth sequence and at least one of the following information, namely, service set color, association identifier, cyclic redundancy check, tail bit, and modulation and coding scheme. The apparatus according to any one of claims 16 to 21.

23. The PPDU further includes a first data field, and the first data field is obtained based on a fifth sequence and an OFDM symbol generated based on information bits. The apparatus according to any one of claims 16 to 22.

24. The first sequence is obtained based on a Barker code, and / or the second sequence is obtained based on a Barker code. The apparatus according to any one of claims 20 to 23.

25. The PPDU further includes a first binary phase shift keying (BPSK) mark field and a second BPSK mark field. The first BPSK mark field or the second BPSK mark field is the same as the L-SIG field, or The first BPSK mark field or the second BPSK mark field is obtained based on the L-SIG field and a third sequence. The apparatus according to any one of claims 16 to 24.

26. The elements in the third sequence include -1 and +1. The apparatus according to claim 25.

27. The PPDU further includes at least one of a repeated legacy signal (RL-SIG) field or a universal signal (U-SIG) field. The apparatus according to any one of claims 16 to 26.

28. The U-SIG field includes at least one of the following information, namely, at least one of the physical layer version of the PPDU and the format of the PPDU, the version number of the physical layer version of the PPDU is greater than 0, the format of the PPDU indicates that the format of the PPDU is an extended range PPDU format. The apparatus according to claim 27.

29. The L-STF, the L-LTF, and the L-SIG field are included in a first portion of the PPDU, the first STF, the first LTF, and the first SIG field are included in a second portion of the PPDU, and a bandwidth of the first portion is larger than a bandwidth of the second portion. The apparatus according to any one of claims 16 to 28.

30. The processing unit is specifically configured to perform cross-correlation or auto-correlation on the first STF and / or to perform maximum likelihood synthesis on at least one of the first LTF, the first SIG field, and the first data field. The apparatus according to any one of claims 23 to 29.

31. A communication device including a processor and a memory, the memory is configured to store instructions, the processor is configured to execute the instructions, and as a result, the method according to any one of claims 1 to 15 is executed. A communication device.

32. A communication device including a logic circuit and an interface, the logic circuit is coupled to the interface, the interface is configured to input and / or output code instructions, and the logic circuit is configured to execute the code instructions, and as a result, the method according to any one of claims 1 to 15 is executed. A communication device.

33. A computer-readable storage medium, the computer-readable storage medium is configured to store a computer program, when the computer program is executed, the method according to any one of claims 1 to 15 is executed. A computer-readable storage medium.

34. A computer program, when the computer program is executed, the method according to any one of claims 1 to 15 is executed. A computer program.

35. A communication system including a transmitting end and a receiving end, the transmitting end is configured to execute the method according to any one of claims 1 and 3 to 15, and the receiving end is configured to execute the method according to any one of claims 2 to 15. A communication system.

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