Communication method and communication apparatus

Abstract

The present application relates to the technical field of wireless communications, and in particular, to a communication method and a communication apparatus. In the present application, a first station sends a long training field on the basis of a long training sequence, and a second station receives the long training field, and performs channel estimation on the basis of the long training field and the long training sequence. The long training sequence satisfies: the sum of elements of a difference sequence corresponding to any DRU is less than or equal to 5, enabling LTFs transmitted on the basis of any DRU to have a low PAPR. The present application can support IEEE protocols, such as the IEEE 802.11be / Wi-Fi 7 / EHT protocol, the IEEE 802.11bn / UHR / Wi-Fi 8 protocol, the IEEE 802.15 / UWB protocols, the IEEE 802.11bf / sensing protocol, the millimeter wave (MMW) protocols, etc. The present application can also support the StarFlash / SparkLink / NearLink standard protocol.

Description

Communication methods and communication devices

[0001] This application claims priority to Chinese Patent Application No. 202411598337.7, filed on November 8, 2024, entitled "Communication Method and Communication Device", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of communication technology, and in particular to a communication method and communication device. Background Technology

[0003] The European Telecommunications Standards Institute (ETSI) has issued regulations for the 6 GHz spectrum, limiting the maximum transmit power to 23 dBm (decibel-milliwatts) and the maximum power spectral density to 10 dBm / MHz (decibel-milliwatts / megahertz). The U.S. Federal Communications Commission (FCC) has also issued regulations for the 6 GHz spectrum, defining a low-power indoor (LPI) communication method with strict limits on maximum transmit power and maximum power spectral density. For access points (APs), the maximum transmit power is limited to 30 dBm, and the maximum power spectral density is 5 dBm / MHz. For stations (STAs), the maximum transmit power is limited to 24 dBm, and the maximum power spectral density is -1 dBm / MHz. The transmit power of a device is limited by both the maximum power and the maximum power spectral density; that is, the transmit power cannot exceed the maximum power value, and the transmitted power spectral density (PSD) cannot exceed the maximum power spectral density. Compared to maximum power, maximum power spectral density is a more stringent limitation, and the maximum power that can be transmitted is usually more constrained by the power spectral density. For a station, the transmission power only reaches the specified maximum power limit when the bandwidth is 320MHz. When the bandwidth is less than 320MHz, due to the limitation of maximum power spectral density, the station can only transmit at a lower power (meaning lower than the specified maximum power).

[0004] Due to the limited power spectral density, the Distributed Resource Unit (DRU) technology was proposed to improve transmission power. The basic idea of ​​DRU is to discretize the continuous subcarriers within a resource unit (RU) across a wider bandwidth to reduce the number of subcarriers within 1 MHz, thereby increasing the transmission power of each subcarrier and thus improving the total transmission power.

[0005] The long training field (LTF) is used for channel estimation. The LTF sequence is designed for each bandwidth and indicates the values ​​carried on each subcarrier during LTF transmission. When a station transmits the data field based on the DRU, it also transmits the LTF based on this DRU.

[0006] However, current LTF sequences are designed for subcarrier-continuous RUs (called conventional RUs). Using LTF sequences designed for conventional RUs for DRUs will result in an excessively high peak-to-average power ratio (PAPR) for LTFs based on DRU transmissions. Summary of the Invention

[0007] This application provides a communication method and communication device that can reduce the PAPR of LTF based on DRU transmission.

[0008] In a first aspect, embodiments of this application provide a communication method, which can be applied to a first site, or to a chip or functional module within the first site. The first site may include a WLAN device such as an IoT device. The method includes:

[0009] Determine a long training sequence that satisfies: y i This is the ratio of the sequence value corresponding to the i-th subcarrier among the subcarriers with an index less than 0 in the 106-tone DRU to the sequence value corresponding to the i-th subcarrier among the subcarriers with an index greater than 0 in the 106-tone DRU; a long training field is transmitted, which is determined based on this long training sequence.

[0010] In the aforementioned 106-tone DRU, the i-th subcarrier among subcarriers with an index less than 0 and the i-th subcarrier among subcarriers with an index greater than 0 are considered a subcarrier pair. For a subcarrier pair, when the sequence values ​​corresponding to the two subcarriers are the same, the energy of the time-domain waveform of the subcarrier pair is mainly concentrated on its even-numbered sample. When the sequence values ​​corresponding to the two subcarriers in a subcarrier pair are opposite, the energy of the time-domain waveform of the subcarrier pair is mainly concentrated on its odd-numbered sample. Therefore, in a 106-tone DRU, the smaller the difference in the number of subcarrier pairs with the same sequence values ​​and subcarrier pairs with opposite sequence values, the closer the energy carried on the odd-numbered sample and the energy carried on the even-numbered sample in the time-domain waveform of the 106-tone DRU becomes, thus resulting in a lower PAPR of the LTF transmitted based on the 106-tone DRU.

[0011] In this embodiment of the application, the quantity difference between subcarrier pairs with the same sequence value and subcarrier pairs with opposite sequence values ​​can be determined by... express, The smaller the value, the lower the PAPR of the LTF based on 106-tone DRU transmission. Therefore, long training sequences satisfy: This enables LTF based on 106-tone DRU to have a lower PAPR.

[0012] Secondly, embodiments of this application provide a communication method, which can be applied to a second site, or to a chip or functional module within the second site. The second site may include WLAN devices such as IoT devices. The method includes:

[0013] Receive a long training field; perform channel estimation based on the long training field and the long training sequence, where the long training sequence satisfies: y i This is the ratio of the sequence value corresponding to the i-th subcarrier among the subcarriers with an index less than 0 in a 106-tone DRU, to the sequence value corresponding to the i-th subcarrier among the subcarriers with an index greater than 0 in a 106-tone DRU.

[0014] In the embodiments of this application, The smaller the value, the lower the PAPR of the LTF based on 106-tone DRU transmission. Therefore, long training sequences satisfy: This enables LTF based on 106-tone DRU to have a lower PAPR.

[0015] In combination with the first or second aspect, in one possible implementation, the long training sequence also satisfies: x i This is the ratio of the sequence value corresponding to the i-th subcarrier among the subcarriers with an index less than 0 in a 52-tone DRU to the sequence value corresponding to the i-th subcarrier among the subcarriers with an index greater than 0 in a 52-tone DRU.

[0016] In this embodiment of the application, the sequence [x1,x2,x3,…,x] is used. 26 This can be referred to as the difference sequence corresponding to the 52-tone DRU. This can be described as the sum of the elements of the difference sequence corresponding to a 52-tone DRU. Long training sequences satisfy: This enables LTF based on 52-tone DRU transmission to have a lower PAPR.

[0017] In combination with the first or second aspect, in one possible implementation, the long training sequence also satisfies: z i This is the ratio of the sequence value corresponding to the i-th subcarrier among the subcarriers with an index less than 0 in the 26-tone DRU to the sequence value corresponding to the i-th subcarrier among the subcarriers with an index greater than 0 in the 26-tone DRU.

[0018] In this embodiment of the application, the sequence [z1,z2,z3,…,z…] is used. 13 This can be referred to as the difference sequence corresponding to the 26-tone DRU. This can be described as the sum of the elements of the difference sequence corresponding to a 26-tone DRU. Long training sequences satisfy: This enables LTF based on 26-tone DRU transmission to have a lower PAPR.

[0019] It is understandable that when a long training sequence simultaneously satisfies: as well as At that time, the long training sequence can balance the PAPR corresponding to 26-tone DRU, 52-tone DRU and 106-tone DRU, so that the LTF based on various DRU transmissions has a low PAPR.

[0020] In conjunction with the first or second aspect, in one possible implementation, the subcarrier range of the 106-tone DRU is [120:9:-12,6:9:114,-116:9:-8,10:9:118,-118:9:-10,8:9:116,-114:9:-6,12:9:120,-3,3]; or, the subcarrier range of the 106-tone DRU is [-119:9:-11,7:9:115,-115:9:-7,11:9:119,-117:9:-9,9:9:117,-113:9:-5,4:9:112,-2,2].

[0021] In conjunction with the first or second aspect, in one possible implementation, the subcarrier range of the 52-tone DRU is: [-120:9:-12,6:9:114,-116:9:-8,10:9:118]; or, the subcarrier range of the 52-tone DRU is: [-118:9:-10,8:9:116,-114:9:-6,12:9:120]; or, the subcarrier range of the 52-tone DRU is: [-119:9:-11,7:9:115,-115:9:-7,11:9:119]; or, the subcarrier range of the 52-tone DRU is: [-117:9:-9,9:9:117,-113:9:-5,4:9:112].

[0022] Combining the first and second aspects, in one possible implementation, the long training sequence is: [0 0 0 0 0 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 -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 0 0 0 0 0 0 0 0].

[0023] In this embodiment of the application, the above-mentioned long training sequence simultaneously satisfies: as well as This long training sequence enables LTFs based on various DRU transmissions to have low PAPR and to balance the transmit power of LTFs corresponding to 26-tone DRU, 52-tone DRU and 106-tone DRU, so that each DRU can operate in a region far from the nonlinear operating region of the power amplifier.

[0024] Thirdly, embodiments of this application provide a communication method, which can be applied to a first site, or to a chip or functional module within the first site. The first site may include a WLAN device such as an IoT device. The method includes:

[0025] A long training sequence is determined, which is: [0 0 0 0 0 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 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 0 0 0 0 0 0 0]; Send the long training field, which is determined based on the assigned DRU and the long training sequence.

[0026] In this embodiment of the application, the above-mentioned long training sequence simultaneously satisfies: as well as This long training sequence enables LTFs based on various DRU transmissions to have low PAPR and to balance the transmit power of LTFs corresponding to 26-tone DRU, 52-tone DRU and 106-tone DRU, so that each DRU can operate in a region far from the nonlinear operating region of the power amplifier.

[0027] Fourthly, embodiments of this application provide a communication method, which can be applied to a second site, or to a chip or functional module within the second site. The second site may include a WLAN device such as an IoT device. The method includes:

[0028] Receive the long training field; perform channel estimation based on the long training field and the long training sequence. The long training sequence is: [0 0 0 0 0 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 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 0 0 0 0 0 0 0 0].

[0029] In this embodiment of the application, the above-mentioned long training sequence simultaneously satisfies: as well as This long training sequence enables LTFs based on various DRU transmissions to have low PAPR and to balance the transmit power of LTFs corresponding to 26-tone DRU, 52-tone DRU and 106-tone DRU, so that each DRU can operate in a region far from the nonlinear operating region of the power amplifier.

[0030] Fifthly, embodiments of this application provide a communication device for executing the methods in any one of the first to fourth aspects or any possible implementations thereof. The first communication device includes a module having the capability to execute the methods in any one of the first to fourth aspects or any possible implementations thereof.

[0031] Sixthly, embodiments of this application provide a communication device including a processor configured to execute the methods shown in any one of the first to fourth aspects or any possible implementation thereof. The processor executes a program stored in a memory, and when the program is executed, the methods shown in any one of the first to fourth aspects or any possible implementation thereof are executed.

[0032] In one possible implementation, the memory is located outside the aforementioned communication device.

[0033] In one possible implementation, the memory is located within the aforementioned communication device.

[0034] In this embodiment, the processor and memory can also be integrated into a single device, that is, the processor and memory can be integrated together. For example, the communication device can be a chip.

[0035] In one possible implementation, the communication device further includes a transceiver for receiving or sending information.

[0036] In a seventh aspect, embodiments of this application provide a chip including logic circuitry and an interface, the logic circuitry and the interface being coupled; the interface is used for inputting and / or outputting information, and the logic circuitry is used to cause the chip to perform the method described in any one of the first to fourth aspects or any possible implementation thereof.

[0037] Eighthly, embodiments of this application provide a computer-readable storage medium for storing a computer program that, when run on a computer, causes the methods shown in any of the first to fourth aspects or any possible implementation thereof to be executed.

[0038] Ninthly, embodiments of this application provide a computer program product that, when run on a computer, causes the methods shown in any of the first to fourth aspects or any possible implementations above to be executed.

[0039] In a tenth aspect, embodiments of this application provide a communication system including a first station and a second station. The first station is configured to perform the method as shown in the first aspect or any possible implementation thereof, and the second station is configured to perform the method as shown in the second aspect or any possible implementation thereof. Alternatively, the first station is configured to perform the method as shown in the third aspect, and the second station is configured to perform the method as shown in the fourth aspect. Attached Figure Description

[0040] Figure 1 is a schematic diagram of the structure of a communication system provided in an embodiment of this application;

[0041] Figure 2 is a schematic diagram of the structure of the LTF provided in an embodiment of this application;

[0042] Figure 3a is a schematic diagram of the LTF sequence corresponding to 20MHz provided in the embodiment of this application;

[0043] Figure 3b is a schematic diagram of the LTF sequence corresponding to 40MHz provided in the embodiments of this application;

[0044] Figure 3c is a schematic diagram of the LTF sequence corresponding to 80MHz provided in the embodiment of this application;

[0045] Figure 4 is a flowchart illustrating the communication method provided in an embodiment of this application;

[0046] Figure 5 is a schematic diagram of a communication device provided in an embodiment of this application;

[0047] Figure 6 is a schematic diagram of another structure of the communication device provided in an embodiment of this application;

[0048] Figure 7 is a schematic diagram of another structure of the communication device provided in the embodiments of this application. Detailed Implementation

[0049] The terms "first" and "second," etc., used in the specification, claims, and drawings of this application are only used to distinguish different objects and not to limit the order, sequence, priority, or importance of multiple objects. In the embodiments of this application, "multiple" refers to two or more. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or devices. Additionally, the character " / ," unless otherwise specified, generally indicates that the preceding and following objects are in an "or" relationship.

[0050] The term "embodiment" as used herein means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art will explicitly and implicitly understand that, unless otherwise specified or logically conflicting, the terminology and / or descriptions between the various embodiments of this application are consistent and can be mutually referenced, and technical features in different embodiments can be combined to form new embodiments based on their inherent logical relationships.

[0051] It should be understood that in this application, "at least one (item)" means one or more, "more than one" means two or more, "at least two (items)" means two or three or more, and "and / or" is used to describe the relationship between related objects, indicating that there can be three relationships. For example, "A and / or B" can mean: only A exists, only B exists, and A and B exist simultaneously, where A and B can be singular or plural. The character " / " generally indicates that the related objects before and after are in an "or" relationship. "At least one (item) of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one (item) of a, b, or c can mean: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, and c can be single or multiple.

[0052] In this application, "send" and "receive" indicate the direction of signal transmission. For example, "send information to XX" can be understood as the destination of the information being XX, which can include direct transmission via the air interface or indirect transmission via the air interface from other units or modules. "Receive information from YY" can be understood as the source of the information being YY, which can include direct reception from YY via the air interface or indirect reception from YY via the air interface from other units or modules. "Send" can also be understood as the "output" of a chip interface, and "receive" can also be understood as the "input" of a chip interface. In other words, sending and receiving can occur between devices, such as between network devices and terminal devices, or within a device, such as between components, modules, chips, software modules, or hardware modules within the device via buses, traces, or interfaces.

[0053] This application will present various aspects, embodiments, or features relating to systems that may include multiple devices, components, modules, etc. It should be understood and appreciated that individual systems may include additional devices, components, modules, etc., and / or may not include all the devices, components, modules, etc. discussed in conjunction with the accompanying drawings. Furthermore, combinations of these approaches are also possible.

[0054] Furthermore, in the embodiments of this application, words such as "exemplarily" and "for example" are used to indicate examples, illustrations, or descriptions. Any embodiment or design scheme described as an "example" in this application should not be construed as being more preferred or advantageous than other embodiments or design schemes. Specifically, the use of the term "example" is intended to present concepts in a concrete manner. In the embodiments of this application, "of," "corresponding, relevant," and "corresponding" may sometimes be used interchangeably, and it should be noted that their intended meanings are consistent unless their distinction is emphasized.

[0055] The communication systems and service scenarios described in the embodiments of this application are for the purpose of more clearly illustrating the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions provided in the embodiments of this application. As those skilled in the art will know, with the evolution of network architecture and the emergence of new service scenarios, the technical solutions provided in the embodiments of this application are also applicable to similar technical problems.

[0056] The following describes the system involved in the embodiments of this application.

[0057] The technical solutions provided in this application can be applied to wireless local area network (WLAN) systems, such as Wi-Fi. For example, the technical solutions provided in this application can be applied to the IEEE 802.11 series of protocols (or standards), such as the 802.11be protocol, the 802.11bn protocol (or Wi-Fi 8, also known as ultra-high reliability (UHR) or ultra-high reliability and throughput (UHRT)), or next-generation protocols of the 802.11bn protocol, or protocols supporting ambient power (AMP), etc., and will not be listed exhaustively. The technical solutions provided in this application can also be applied to wireless personal area networks (WPANs) based on millimeter wave (MMW) and ultra-wideband (UWB) technologies. The technical solutions provided in the embodiments of this application can be applied to the IEEE 802.15 series protocols, such as the 802.15.4a, 802.15.4z, or 802.15.4ab protocols, or future UWB WPAN protocols, etc., and will not be listed one by one. The technical solutions provided in the embodiments of this application can also be applied to the Spark Link or NearLink standard protocol. The technical solutions provided in the embodiments of this application can also be applied to the following communication systems, such as Internet of Things (IoT) systems, vehicle-to-everything (V2X, where X can represent anything), device-to-device (D2D), narrowband Internet of Things (NB-IoT) systems, long term evolution (LTE) systems, 5th generation (5G) communication systems, and new communication systems that will emerge in the future development of communication, etc. For example, V2X can include vehicle-to-vehicle (V2V), vehicle-to-infrastructure (V2I), vehicle-to-pedestrian (V2P), or vehicle-to-network (V2N) communication.

[0058] WLAN systems can provide high-speed, low-latency transmission. As WLAN application scenarios continue to evolve, WLAN systems will be applied to more scenarios or industries, such as the Internet of Things industry, the Internet of Vehicles industry, the banking industry, enterprise offices, stadiums and exhibition halls, concert halls, hotel rooms, dormitories, hospital wards, classrooms, shopping malls, squares, streets, production workshops and warehouses, etc. Of course, devices that support WLAN communication or sensing (such as access points or sites) can be sensor nodes in smart cities (such as smart water meters, smart electricity meters, and smart air monitoring nodes), smart devices in smart homes (such as smart cameras, projectors, displays, televisions, speakers, refrigerators, and washing machines), nodes in the Internet of Things (IoT), entertainment terminals (such as wearable devices for augmented reality (AR) and virtual reality (VR), smart devices in smart offices (such as printers, projectors, loudspeakers, and speakers), vehicle-to-everything (V2X) devices, infrastructure in daily life scenarios (such as vending machines, self-service navigation kiosks in supermarkets, self-service checkout machines, and self-service ordering machines), and equipment in large sports and music venues.

[0059] Although the embodiments of this application primarily use WLAN as an example, especially networks applied to the IEEE 802.11 series of standards, the various aspects involved in the embodiments of this application can be extended to other networks employing various standards or protocols. For example, Bluetooth, high-performance radio LAN (HIPERLAN) (a wireless standard similar to the IEEE 802.11 standard), and wide area networks (WANs) or other networks now known or to be developed in the future.

[0060] In one possible implementation, the method provided in this application embodiment can be implemented by a communication device in a communication system. For example, the communication device can be an access point (AP) or a station (STA).

[0061] An Access Point (AP) is a device with wireless communication capabilities that supports communication, sensing, or power transmission using WLAN protocols. It has the function of communicating or sensing with other devices in a WLAN network (such as non-access point stations (non-AP STAs) or other access points), and can also have the function of communicating, sensing, or transmitting power with other devices. Alternatively, an access point acts as a bridge connecting wired and wireless networks, primarily connecting various wireless network clients together and then connecting the wireless network to an Ethernet network. In a WLAN system, an access point can be called an Access Point Station (AP STA). This wireless communication device can be a complete device or a chip, processing system, or functional module installed within a complete device. Devices with these chips, processing systems, or functional modules can implement the methods and functions of the embodiments in this application under the control of the chips, processing systems, or functional modules. The AP in the embodiments of this application is a device that provides services to non-AP STAs and can support 802.11 series protocols or subsequent protocols. For example, an access point can be an access point for a terminal (such as a mobile phone) to enter a wired (or wireless) network, mainly deployed in homes, buildings, and parks, with a typical coverage radius of tens to hundreds of meters. Of course, it can also be deployed outdoors. Another example is that an AP can be a communication entity such as a communication server, router, switch, or bridge; APs can include various forms of macro base stations, micro base stations, and repeater stations. Of course, an AP can also be a chip, processing system, or module within the above-mentioned devices, thereby implementing the methods and functions of the embodiments of this application.

[0062] A Station-Style (STA) is a device with wireless communication capabilities that supports communication, sensing, or power transmission using the WLAN protocol. It has the ability to communicate, sense, or transmit power with other non-AP STAs or access points in a WLAN network. In a WLAN system, a station can be called a non-access point station (non-AP STA). For example, an STA is any user communication device that allows a user to communicate with an AP (Access Point) or sense or transmit power, and thus communicate with the WLAN. This wireless communication device can be a complete device, or it can be a chip, processing system, or functional module installed in a complete device. Devices with these chips, processing systems, or functional modules can implement the methods and functions of the embodiments of this application under the control of the chips, processing systems, or functional modules. For example, an STA can be a wireless communication chip, a wireless sensor, or a wireless communication terminal, and can also be referred to as a user. Furthermore, an STA can be a mobile phone supporting Wi-Fi communication, a tablet computer supporting Wi-Fi communication, a set-top box supporting Wi-Fi communication, a smart TV supporting Wi-Fi communication, a smart wearable device supporting Wi-Fi communication, an in-vehicle communication device supporting Wi-Fi communication, and a computer supporting Wi-Fi communication. Of course, STA can also be a chip, processing system, or module in the various types of devices described above, thereby implementing the methods and functions of the embodiments of this application.

[0063] For example, the communication systems to which the methods provided in this application can be applied may include access points and stations. For instance, this application can be applied to scenarios of communication or sensing between APs and STAs, between APs, or between STAs in a WLAN, and this application does not limit this. Optionally, an AP can communicate or sense with a single STA, or an AP can communicate or sense with multiple STAs simultaneously. Specifically, communication or sensing between an AP and multiple STAs can be further divided into downlink transmission where the AP simultaneously sends signals to multiple STAs, and uplink transmission where multiple STAs send signals to the AP. The communication protocols between APs and STAs, between APs, and between STAs can support WLAN communication protocols, which may include IEEE 802.11 series protocols, such as the 802.11bn protocol, and of course, protocols after 802.11bn are also applicable.

[0064] Figure 1 is a schematic diagram of the communication system provided in 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, such as AP1 and AP2, and three stations, such as STA1, STA2, and STA3. As an example, the method provided in this embodiment can be applied to data communication, sensing, or power transmission between an AP and one or more STAs, such as the communication or sensing between AP1 and STA1 as shown in Figure 1, and the communication or sensing between AP1 and STA1 / STA2 as shown in Figure 1. As another example, the method provided in this embodiment can be applied to communication between APs, such as the communication or sensing between AP1 and AP2 as shown in Figure 1. As yet another example, the method provided in this embodiment can be applied to communication or sensing between STAs, such as the communication or sensing between STA2 and STA3 as shown in Figure 1.

[0065] Figure 1 uses STA (Mobile Phone) and AP (Router) as an example, and does not imply a limitation on the types of APs and STAs in this application embodiment. Furthermore, the number of APs and STAs shown in Figure 1 is merely an example; in a specific implementation, the number of APs or STAs may be more or less, and this application embodiment does not limit this.

[0066] The following describes the terms or nouns used in the embodiments of this application.

[0067] 1. Distributed Resource Unit (DRU)

[0068] Recently, the U.S. Federal Communications Commission (FCC) issued regulations regarding the 6 GHz spectrum, defining a low-power indoor (LPI) communication method with strict limits on maximum transmit power and maximum frequency spectral density. For example, for a station (STA), the maximum power is 24 dBm, and the maximum power spectral density is -1 dBm / MHz. The transmit power of a device is limited by both the maximum power and the maximum power spectral density; firstly, the transmit power cannot exceed the maximum power value, and secondly, the transmit power spectral density cannot exceed the maximum power spectral density. Compared to maximum power, the limitation on maximum power spectral density is more stringent, and the maximum transmit power is usually more constrained by the power spectral density. For a station, the maximum power limit stipulated by the regulations is only reached when the bandwidth is at its maximum of 320 MHz. Below this bandwidth, due to the limitation on maximum power spectral density, only lower power can be transmitted. On June 30, 2021, Europe also issued regulations for the 6 GHz spectrum, targeting LPI communication methods, such as a maximum power of 23 dBm and a maximum power spectral density of 10 dBm / MHz. When the bandwidth does not exceed 20MHz, the transmission power of the AP / STA is mainly limited by the power spectral density, while when the bandwidth is greater than 20MHz, the transmission power of the AP / STA is mainly limited by the maximum power.

[0069] Due to the limited power spectral density, discretizing a finite number of subcarriers (such as a 26-tone RU) across a wider bandwidth, i.e., more subcarriers (such as an odd number of subcarriers in two 26-tone RUs), can increase the transmission power. This is known as a discrete RU, or distributed RU. It is commonly used in uplink multi-user transmissions, where multiple users interleave discrete RUs to increase the transmission power of each user within a fixed bandwidth. It should be noted that the maximum power spectral density is limited in the form of a transmission power of no more than x dBm per 1 MHz. Considering a carrier spacing of 78.125 kHz, 1 MHz contains 12.8 (approximately 13) subcarriers. Since the average power of each subcarrier is the same during a single transmission, observing any consecutive 13 subcarriers, the maximum number of subcarriers carrying the signal determines the average power of each subcarrier, and thus the transmission power of the signal. For example, with a 20MHz bandwidth (242 subcarriers in total), if a maximum of 5 out of every 13 consecutive subcarriers carry signals, then the average power of each subcarrier will be x(dBm) / 5. Considering there are 26 subcarriers carrying signals, the total transmission power will be x(dBm) / 5*26.

[0070] The DRU in this application includes multiple subcarriers discrete in the frequency domain, or multiple subcarriers discrete indices (or index values), or multiple subcarriers with discontinuous indices. These discrete subcarriers can be partially discrete or completely discrete. For example, the discrete subcarriers may include some subcarriers that are frequency-continuous, and some subcarriers that are frequency-discontinuous. Alternatively, the discrete subcarriers may be completely frequency-discontinuous. The phrase "frequency-continuous" can also be interpreted as "the indices of the subcarriers are continuous," and "frequency-discontinuous" can also be interpreted as "the indices of the subcarriers are discontinuous." In this application, "distributed RU" and "DRU" or "discrete RU" can be used interchangeably. It should also be understood that the DRU mentioned in this application refers to an RU with discrete subcarriers in the frequency domain. That is, an RU with this characteristic is referred to as a distributed RU or discrete RU in this application, but in practice, an RU with this characteristic may have other names, which this application does not limit.

[0071] In this application, a continuous RU refers to an RU consisting of multiple consecutive subcarriers, or a continuous RU consisting of two groups of consecutive subcarriers, where each group of consecutive subcarriers includes multiple consecutive subcarriers, and the two groups of consecutive subcarriers are separated only by guard subcarriers, empty subcarriers, or DC subcarriers. Of course, a continuous RU can also be called by other names, such as a regular RU (rRU). "Continuous RU" and "regular RU" can be used interchangeably, and this application does not limit the name of the continuous RU.

[0072] The subcarrier planning (tone plan) of DRU is designed based on the following three principles: First, the size and number of DRUs are the same as those of rRUs; second, the hierarchical relationship between DRUs of different sizes is the same as that of rRUs; and third, there are reusable rRU indication tables (such as Table 1 and Table 2 shown above).

[0073] As a possible example, when the discrete bandwidth is 20MHz, the discrete bandwidth (20MHz) can consist of various combinations of 26-tone DRUs, 52-tone DRUs, and 106-tone DRUs. Here, discrete bandwidth refers to the discrete range of DRU subcarriers. Table 1 shows an example of subcarrier planning with a discrete bandwidth of 20MHz. The two square brackets in Table 1 indicate the index of a 26-tone DRU. As shown in Table 1, 20MHz can include nine 26-tone DRUs (26-tone DRU1 to 26-tone DRU9), or four 52-tone DRUs (52-tone DRU1 to 52-tone DRU4), or two 106-tone DRUs (106-tone DRU1 to 106-tone DRU2). The subcarrier range of 26-tone DRU1 is [-120:9:-12, 6:9:114], the subcarrier range of 26-tone DRU2 is [-116:9:-8, 10:9:118], ..., and the subcarrier range of 26-tone DRU9 is [-113:9:-5, 4:9:112]. 52-tone DRU1 can be considered a combination of 26-tone DRU1 and 26-tone DRU2. The subcarrier range of 52-tone DRU1 is 26-tone[DRU1,DRU2], which is [-120:9:-12, 6:9:114, -116:9:-8, 10:9:118]. 52-tone DRU2 can be seen as a combination of 26-tone DRU3 and 26-tone DRU4; 52-tone DRU3 can be seen as a combination of 26-tone DRU6 and 26-tone DRU7; and 52-tone DRU4 can be seen as a combination of 26-tone DRU8 and 26-tone DRU9. 106-tone DRU1 can be seen as a combination of 26-tone DRU1 to 26-tone DRU4, subcarriers with index -3, and subcarriers with index 3; and 106-tone DRU2 can be seen as a combination of 26-tone DRU6 to 26-tone DRU9, subcarriers with index -2, and subcarriers with index 2.

[0074] Table 1

[0075] In this application, [a:b:c] can refer to all integers from a to c (where a and c are also integers), with a step size of b. That is: a, (a+b), (a+2b), (a+3b), ..., c. Whether the last value c can be obtained depends on whether ca is exactly an integer multiple of b. If not, element c is not included. When b equals 1, [a:c] can usually be used to represent [a:1:c]. For example, [-128:127] represents -128, -127, -126, -125, ..., 125, 126, 127.

[0076] As another possible example, when the discrete bandwidth is 40MHz, the discrete bandwidth (40MHz) can consist of various combinations of 26-tone DRUs, 52-tone DRUs, 106-tone DRUs, and 242-tone DRUs. Table 2 shows an example of subcarrier planning for a discrete bandwidth of 40MHz. As shown in Table 2, 40MHz can include 18 26-tone DRUs (26-tone DRU1 to 26-tone DRU18), or 8 52-tone DRUs (52-tone DRU1 to 52-tone DRU8), or 4 106-tone DRUs (106-tone DRU1 to 106-tone DRU4), or 2 242-tone DRUs (242-tone DRU1 to 242-tone DRU2). The subcarrier ranges of each DRU are shown in Table 2 and will not be listed here individually.

[0077] Table 2

[0078] As another possible example, when the discrete bandwidth is 80MHz, the discrete bandwidth (80MHz) can consist of various combinations of 52-tone DRUs, 106-tone DRUs, 242-tone DRUs, and 484-tone DRUs. Table 3 shows an example of subcarrier planning for a discrete bandwidth of 80MHz. As shown in Table 3, 80MHz can include 16 52-tone DRUs (52-tone DRU1 to 52-tone DRU16), or 8 106-tone DRUs (106-tone DRU1 to 106-tone DRU8), or 4 242-tone DRUs (242-tone DRU1 to 242-tone DRU4), or 2 484-tone DRUs (484-tone DRU1 to 484-tone DRU2). The subcarrier ranges of each DRU are shown in Table 3 and will not be listed here individually.

[0079] Table 3

[0080] It should be noted that for 80MHz subcarrier planning, each 52-tone DRU can also be regarded as a combination of two 26-tone DRUs, except that 26-tone DRUs are not supported in 80MHz subcarrier planning.

[0081] 2. Long training field (LTF)

[0082] The LTF field is used for channel estimation. The LTF sequence is designed for each bandwidth and specifies the values ​​carried on each subcarrier during LTF transmission. In multi-stream scenarios, channel estimation for each stream is performed by transmitting multiple OFDM symbols. The transmission method for data subcarriers can be described as follows: To maintain the orthogonality of the LTFs for each stream, the elements of the P matrix are multiplied by the LTF. Taking the case with 4 LTFs as an example, the corresponding P matrix is:

[0083] The LTF is constructed as shown in Figure 2. In this construction mode, the kth element of the LTF sequence is carried on the kth subcarrier. k The LTF of the nth OFDM symbol corresponding to the mth space-time stream is multiplied by the element in the mth row and nth column of the P matrix. Therefore, for the stream that has passed through channel H k Then, the receiver receives the frequency domain signal Y. k It can be represented as: Y k =H k P 4*4 LTF k

[0084] Furthermore, since matrix P is an orthogonal matrix ( Here, I is the identity matrix, and * is the conjugate transpose of the matrix. Therefore, the channel on the k-th subcarrier... In this way, the MIMO channel corresponding to the k-th subcarrier can be estimated. The above construction method is for the data subcarrier of the LTF. An RU includes data subcarriers and pilot subcarriers. For the pilot subcarrier, the corresponding LTF construction method is similar to that of the data subcarrier. The pilot subcarrier uses an R matrix, where the correspondence between the R matrix and the P matrix is: R(m,n)=P(1,n), that is, each row of the R matrix is ​​equal to the first row of the P matrix.

[0085] When the number of LTFs is less than 4, the LTF field can include part of the content in the structure shown in Figure 2. For example, when the number of spatial streams is 1, the LTF field can include the first LTF of the first spacetime stream shown in Figure 2. Similarly, when the number of spatial streams is 2, the LTF field can include the first two LTFs of the first spatial stream and the first two LTFs of the second spatial stream. When the number of spatial streams is 3, the LTF field can include the LTFs corresponding to the first three spatial streams shown in Figure 2.

[0086] For example, a spatial flow can correspond to a circular shift diversity (CSD), as shown in Figure 2. The CSD corresponding to the first spatial flow is 0 ns, the CSD corresponding to the second spatial flow is -400 ns, the CSD corresponding to the third spatial flow is -200 ns, and the CSD corresponding to the fourth spatial flow is -600 ns.

[0087] LTF sequences are divided into 1x, 2x, and 4x sequences. In an LTF1x sequence, there are at least three zeros between two non-zero elements; in an LTF2x sequence, there is at least one zero between two non-zero elements; and in an LTF4x sequence, there are consecutive non-zero elements. The LTF4x sequence has the densest concentration of non-zero elements, thus providing the most accurate channel estimation. The 802.11ax / 802.11be protocol specifies LTF1x, LTF2x, and LTF4x sequences for different bandwidths.

[0088] For example, for a 4x sequence with a 20MHz bandwidth, the 20MHz bandwidth corresponds to 256 subcarriers, whose indices are denoted as -128:127. Among them, the LTF sequence value corresponding to the subcarrier with index -122:122 can be as shown in Figure 3a, and the subcarriers with other indices carry a value of 0.

[0089] For example, for a 4x sequence with a 40M bandwidth, the 40M bandwidth corresponds to 512 subcarriers, whose indices are denoted as -256:255. Among them, the LTF sequence value corresponding to the subcarrier with index -244:244 can be shown in Figure 3b, and the subcarriers with other indices carry a value of 0.

[0090] For example, consider a 4x sequence with an 80MHz bandwidth; the 80MHz bandwidth corresponds to 1024 subcarriers, whose indices are denoted as -500:500. The LTF sequence value corresponding to the subcarrier with index -500:500 can be shown in Figure 3c, while the subcarriers with other indices carry a value of 0.

[0091] However, the LTF sequences shown in Figures 3a to 3c above are designed for rRU. Directly using LTF sequences designed for rRU for DRU will result in an excessively high peak to average power ratio (PAPR) for LTFs based on DRU transmission.

[0092] In view of this, embodiments of this application provide a communication method and a communication apparatus that can reduce the PAPR of LTF based on DRU transmission. The method provided by embodiments of this application can be applied to the communication system shown in FIG1. ​​For example, embodiments of this application are applied to a first site and a second site, where the first site can be the STA described above, and the second site can be the AP described above.

[0093] Please refer to Figure 4, which is a flowchart illustrating a communication method provided in an embodiment of this application. As shown in Figure 4, the method includes, but is not limited to, the following steps.

[0094] 401, the first site determines the long training sequence.

[0095] This long training sequence, also known as the LTF sequence, is used to indicate the values ​​carried on each subcarrier during LTF transmission. The value carried on a subcarrier is determined based on the sequence value corresponding to that subcarrier in the LTF sequence, as well as the P matrix or R matrix. In the embodiments of this application, "long training sequence" and "LTF sequence" can be used interchangeably.

[0096] For example, the first station can determine a long training sequence based on discrete bandwidth.

[0097] For a detailed explanation of this long training field, please refer to the following text, which will not be elaborated here.

[0098] 402, the first station sends the long training field, and the corresponding second station receives the long training field.

[0099] The Long Training Field (LTF) is determined based on the long training sequence. For example, the long training field is determined based on the assigned DRUs and the long training sequence. In the long training field, the LTF sequence value corresponding to the assigned DRUs is determined based on the long training sequence, and the LTF sequence value corresponding to the unassigned DRUs is 0.

[0100] For example, the assigned DRU may be indicated by a trigger frame sent by the second station. After receiving the trigger frame, the first station determines the assigned DRU based on the indication in the trigger frame.

[0101] For example, the assigned DRU is a 26-tone DRU, a 52-tone DRU, or a 106-tone DRU. For instance, in the case of a discrete bandwidth of 20MHz, the assigned DRU can be any DRU as shown in Table 3.

[0102] The time-domain waveform of the long training field may be affected by noise during channel transmission. Therefore, the time-domain waveform of the long training field received by the second station may differ from the time-domain waveform of the long training field sent by the first station.

[0103] 403, The second station performs channel estimation based on long training fields and long training sequences.

[0104] For example, the second station stores a long training sequence. The time-domain waveform of the long training field is Fourier transformed to obtain the frequency-domain signal corresponding to the long training field. The second station performs channel estimation based on the frequency-domain signal and the sequence values ​​corresponding to the DRUs allocated in the long training sequence stored by the second station.

[0105] Regarding the aforementioned long training sequences, this application provides the following implementation methods:

[0106] Implementation Method 1: The long training sequence satisfies: y i This is the ratio of the sequence value corresponding to the i-th subcarrier among the subcarriers with an index less than 0 in a 106-tone DRU, to the sequence value corresponding to the i-th subcarrier among the subcarriers with an index greater than 0 in the same 106-tone DRU. That is, y i This is the ratio of the sequence value corresponding to the i-th subcarrier in the negative half-frequency of the 106-tone DRU to the sequence value corresponding to the i-th subcarrier in the positive half-frequency of the same 106-tone DRU. The index of the subcarrier in the negative half-frequency is less than 0, and the index of the subcarrier in the positive half-frequency is greater than 0.

[0107] Sequence [y1, y2, y3, ..., y 53 This can be referred to as the difference sequence corresponding to the 106-tone DRU. It can be called the sum of the elements of the difference sequence corresponding to 106-tone DRU.

[0108] The sequence value of an LTF sequence is either 1 or -1, therefore, y i This can be used to indicate whether the sequence value corresponding to the i-th subcarrier among the subcarriers with an index less than 0 in a 106-tone DRU is the same as the sequence value corresponding to the i-th subcarrier among the subcarriers with an index greater than 0 in the same 106-tone DRU. For example, y iA value of 1 indicates that the sequence value corresponding to the i-th subcarrier among the subcarriers with an index less than 0 in the 106-tone DRU is the same as the sequence value corresponding to the i-th subcarrier among the subcarriers with an index greater than 0 in the same 106-tone DRU. For example, y i A value of -1 indicates that the sequence value corresponding to the i-th subcarrier among the subcarriers with an index less than 0 in the 106-tone DRU is opposite to (or different from) the sequence value corresponding to the i-th subcarrier among the subcarriers with an index greater than 0 in the same 106-tone DRU.

[0109] Among some possible implementations, You can also replace the description with: or Where ai is the sequence value corresponding to the i-th subcarrier among the subcarriers with an index less than 0 in the 106-tone DRU, and bi is the sequence value corresponding to the i-th subcarrier among the subcarriers with an index greater than 0 in the 106-tone DRU. For any 106-tone DRU, let the sequence values ​​corresponding to the 53 subcarriers contained in its negative half-frequency be [a1, a2, a3, ..., a 53 Let the LTF values ​​corresponding to the 53 subcarriers contained in its positive half-frequency be [b1, b2, b3, ..., b]. 53 Let [y1,y2,y3,…,y] 53 ] = [a1 / b1,a2 / b2,a3 / b3,…,a 53 / b 53 ], or let [y1,y2,y3,…,y 53 ] = [b1 / a1,b2 / a2,b3 / a3,…,b 53 / a 53 ].

[0110] For example, the 106-tone DRU can be any 106-tone DRU corresponding to the discrete bandwidth. For instance, the 106-tone DRU can be any one of 106-tone DRU1 and 106-tone DRU2 shown in Table 1. Similarly, the 106-tone DRU can be any one of 106-tone DRU1 to 106-tone DRU4 shown in Table 2. And again, the 106-tone DRU can be any one of 106-tone DRU1 to 106-tone DRU8 shown in Table 3. That is, the sequence value corresponding to any 106-tone DRU within the discrete bandwidth satisfies:

[0111] As an example, with a discrete bandwidth of 20MHz, the subcarrier range of the 106-tone DRU is [-120:9:-12,6:9:114,-116:9:-8,10:9:118,-118:9:-10,8:9:116,-114:9:-6,12:9:120,-3,3], that is, the subcarrier indices of the 106-tone DRU are [-120,-118,-116,-114,-111,-109,……,-12,-10,-8,-6,-3,3,6,8,10,12,……111,114,116,118,120]. This 106-tone DRU can be the 106-tone DRU1 shown in Table 1. y1 is the ratio between the sequence value corresponding to the subcarrier with index -120 and the sequence value corresponding to the subcarrier with index 3, y2 is the ratio between the sequence value corresponding to the subcarrier with index -118 and the sequence value corresponding to the subcarrier with index 6, ..., y 52 y is the ratio between the sequence value corresponding to the subcarrier with index -6 and the sequence value corresponding to the subcarrier with index 118. 53 This is the ratio between the sequence value corresponding to the subcarrier with index -3 and the sequence value corresponding to the subcarrier with index 120.

[0112] As another example, with a discrete bandwidth of 20MHz, the subcarrier range of the 106-tone DRU is [-119:9:-11,7:9:115,-115:9:-7,11:9:119,-117:9:-9,9:9:117,-113:9:-5,4:9:112,-2,2]. That is, the subcarrier indices of the 106-tone DRU are [-119,-117,-115,-113,-110,-108,……,-11,-9,-7,-5,-2,2,5,7,9,11,……110,113,115,117,119]. This 106-tone DRU can be the 106-tone DRU2 shown in Table 1. y1 is the ratio between the sequence value corresponding to the subcarrier with index -119 and the sequence value corresponding to the subcarrier with index 2, y2 is the ratio between the sequence value corresponding to the subcarrier with index -117 and the sequence value corresponding to the subcarrier with index 5, ..., y 52 y is the ratio between the sequence value corresponding to the subcarrier with index -5 and the sequence value corresponding to the subcarrier with index 117. 53 This is the ratio between the sequence value corresponding to the subcarrier with index -2 and the sequence value corresponding to the subcarrier with index 119.

[0113] The above shows some examples of the subcarrier range of a 106-tone DRU. For more information on the subcarrier range of a 106-tone DRU, please refer to the relevant provisions in the protocols (such as 802.11ax / 802.11be), which will not be listed here.

[0114] In this embodiment, the i-th subcarrier among the subcarriers with an index less than 0 in the 106-tone DRU and the i-th subcarrier among the subcarriers with an index greater than 0 in the same 106-tone DRU can be considered as a subcarrier pair (or subcarrier group). The 106-tone DRU can include 53 subcarrier pairs, and each subcarrier pair includes two subcarriers. Specifically, in X subcarrier pairs, the two subcarriers have the same sequence values, and in Y subcarrier pairs, the two subcarriers have opposite sequence values. It can be used to represent the absolute value of the difference between X and Y. X + Y = 53.

[0115] For a subcarrier pair, when the sequence values ​​corresponding to the two subcarriers are the same, the values ​​at the odd-numbered samples (e.g., the 1st, 3rd, 5th, 7th, ... samples) of the time-domain waveforms of the two subcarriers are opposite, while the values ​​at the even-numbered samples (e.g., the 2nd, 4th, 6th, 8th, ... samples) of the time-domain waveforms of the two subcarriers are the same. The time-domain waveform of this subcarrier pair is the superposition of the time-domain waveforms of the two subcarriers; therefore, the energy of the time-domain waveform of this subcarrier pair is mainly concentrated at its even-numbered samples.

[0116] When the sequence values ​​corresponding to the two subcarriers in a subcarrier pair are opposite, the values ​​at the even-numbered samples (e.g., the 2nd, 4th, 6th, 8th, ... samples) of the time-domain waveforms of the two subcarriers are opposite, while the values ​​at the odd-numbered samples (e.g., the 1st, 3rd, 5th, 7th, ... samples) of the time-domain waveforms of the two subcarrier pairs are the same. The energy of the time-domain waveform of this subcarrier pair is mainly concentrated at its odd-numbered samples.

[0117] The time-domain waveform of a 106-tone DRU is a superposition of the time-domain waveforms of each of its constituent subcarriers. Among the 53 subcarrier pairs contained in a 106-tone DRU, the smaller the absolute value of the difference between X and Y (i.e., the closer the values ​​of X and Y), and the closer the number of subcarrier pairs with the same sequence values ​​to the number of subcarrier pairs with opposite sequence values, the more similar the energy carried by odd-numbered samples and even-numbered samples in the time-domain waveform of the 106-tone DRU. This results in a lower PAPR for LTF transmission based on the 106-tone DRU.

[0118] In this embodiment, the absolute value of the sum of the elements of the difference sequence corresponding to the 106-tone DRU is less than or equal to 5, that is, the absolute value of the difference between X and Y is less than or equal to 5. This can make the LTF based on the 106-tone DRU have a lower PAPR, thereby enabling the transmission power of the LTF based on the 106-tone DRU to be far away from the nonlinear region of the power amplifier and reduce the nonlinear interference it is subjected to.

[0119] Implementation Method 2: Long training sequences satisfy: x i x is the ratio of the sequence value corresponding to the i-th subcarrier among the subcarriers with an index less than 0 in a 52-tone DRU, to the sequence value corresponding to the i-th subcarrier among the subcarriers with an index greater than 0 in a 52-tone DRU. That is, x i This is the ratio of the sequence value corresponding to the i-th subcarrier of the negative half-frequency in the 52-tone DRU to the sequence value corresponding to the i-th subcarrier of the positive half-frequency in the same 52-tone DRU.

[0120] Sequence [x1,x2,x3,…,x] 26 This can be referred to as the difference sequence corresponding to the 52-tone DRU. It can be called the sum of the elements of the difference sequence corresponding to the 52-tone DRU.

[0121] x i This can be used to indicate whether the sequence value corresponding to the i-th subcarrier among the subcarriers with an index less than 0 in a 52-tone DRU is the same as the sequence value corresponding to the i-th subcarrier among the subcarriers with an index greater than 0 in the same 52-tone DRU. For example, x i A value of 1 indicates that the sequence value corresponding to the i-th subcarrier among the subcarriers with an index less than 0 in the 52-tone DRU is the same as the sequence value corresponding to the i-th subcarrier among the subcarriers with an index greater than 0 in the same 52-tone DRU. For example, x i A value of -1 indicates that the sequence value corresponding to the i-th subcarrier among the subcarriers with an index less than 0 in the 52-tone DRU is the opposite of the sequence value corresponding to the i-th subcarrier among the subcarriers with an index greater than 0 in the same 52-tone DRU.

[0122] Among some possible implementations, You can also replace the description with: or Among them, c i d represents the sequence value corresponding to the i-th subcarrier among the subcarriers with an index less than 0 in a 52-tone DRU. iLet be the sequence value corresponding to the i-th subcarrier among the subcarriers with an index greater than 0 in a 52-tone DRU. For any 52-tone DRU, let the sequence values ​​corresponding to the 26 subcarriers contained in its negative half-frequency be [c1, c2, c3, ..., c 26 Let the LTF values ​​corresponding to the 26 subcarriers contained in its positive half-frequency be [d1, d2, d3, ..., d]. 26 Let [x1,x2,x3,…,x] 26 ] = [c1 / d1,c2 / d2,c3 / d3,…,c 26 / d 26 ], or let [x1,x2,x3,…,x 26 ] = [d1 / c1,d2 / c2,d3 / c3,…,d 26 / c 26 ].

[0123] For example, a 52-tone DRU can be any 52-tone DRU corresponding to a discrete bandwidth. For instance, a 52-tone DRU can be any one of the 52-tone DRU1 to 52-tone DRU4 shown in Table 1. Similarly, a 52-tone DRU can be any one of the 52-tone DRU1 to 52-tone DRU8 shown in Table 2. And again, a 52-tone DRU can be any one of the 52-tone DRU1 to 52-tone DRU16 shown in Table 3. That is, the sequence value corresponding to any 52-tone DRU within the discrete bandwidth satisfies:

[0124] As an example, with a discrete bandwidth of 20MHz, the subcarrier range of the 52-tone DRU is [-120:9:-12,6:9:114,-116:9:-8,10:9:118], that is, the subcarrier indices of the 52-tone DRU are [-120,-116,-111,-107,...,-12,-8,6,10,15,...109,114,118]. This 52-tone DRU can be the 52-tone DRU1 shown in Table 1. x1 is the ratio between the sequence value corresponding to the subcarrier with index -120 and the sequence value corresponding to the subcarrier with index 6, x2 is the ratio between the sequence value corresponding to the subcarrier with index -116 and the sequence value corresponding to the subcarrier with index 10, ..., x 25 y is the ratio between the sequence value corresponding to the subcarrier with index -12 and the sequence value corresponding to the subcarrier with index 114. 26This is the ratio between the sequence value corresponding to the subcarrier with index -8 and the sequence value corresponding to the subcarrier with index 118.

[0125] As another example, with a discrete bandwidth of 20MHz, the subcarrier range of the 52-tone DRU is [-118:9:-10, 8:9:116, -114:9:-6, 12:9:120]. That is, the subcarrier indices of the 52-tone DRU are [-118, -114, -109, -105, ..., -19, -15, -10, -6, 8, 12, 17, 21, ..., 107, 111, 116, 120]. This 52-tone DRU can be the 52-tone DRU2 shown in Table 1. x1 is the ratio between the sequence value corresponding to the subcarrier with index -118 and the sequence value corresponding to the subcarrier with index 8, x2 is the ratio between the sequence value corresponding to the subcarrier with index -114 and the sequence value corresponding to the subcarrier with index 12, ..., x 25 x is the ratio between the sequence value corresponding to the subcarrier with index -10 and the sequence value corresponding to the subcarrier with index 116. 26 This is the ratio between the sequence value corresponding to the subcarrier with index -6 and the sequence value corresponding to the subcarrier with index 120.

[0126] As another example, with a discrete bandwidth of 20MHz, the subcarrier range of the 52-tone DRU is [-119:9:-11,7:9:115,-115:9:-7,11:9:119]. That is, the subcarrier indices of the 52-tone DRU are [-119,-115,-110,-106,...,-20,-16,-11,-7,7,11,16,20,...,106,110,115,119]. This 52-tone DRU can be the 52-tone DRU3 shown in Table 1. x1 is the ratio between the sequence value corresponding to the subcarrier with index -119 and the sequence value corresponding to the subcarrier with index 7, x2 is the ratio between the sequence value corresponding to the subcarrier with index -115 and the sequence value corresponding to the subcarrier with index 11, ..., x 25 x is the ratio between the sequence value corresponding to the subcarrier with index -11 and the sequence value corresponding to the subcarrier with index 115. 26 This is the ratio between the sequence value corresponding to the subcarrier with index -7 and the sequence value corresponding to the subcarrier with index 119.

[0127] As another example, with a discrete bandwidth of 20MHz, the subcarrier range of the 52-tone DRU is [-117:9:-9, 9:9:117, -113:9:-5, 4:9:112]. That is, the subcarrier indices of the 52-tone DRU are [-117, -113, -108, -104, ..., -18, -14, -9, -5, 4, 9, 13, 18, ..., 103, 108, 112, 117]. This 52-tone DRU can be the 52-tone DRU4 shown in Table 1. x1 is the ratio between the sequence value corresponding to the subcarrier with index -117 and the sequence value corresponding to the subcarrier with index 4, x2 is the ratio between the sequence value corresponding to the subcarrier with index -113 and the sequence value corresponding to the subcarrier with index 9, ..., x 25 x is the ratio between the sequence value corresponding to the subcarrier with index -9 and the sequence value corresponding to the subcarrier with index 112. 26 This is the ratio between the sequence value corresponding to the subcarrier with index -5 and the sequence value corresponding to the subcarrier with index 117.

[0128] The above shows several examples of the subcarrier range of a 52-tone DRU. For more information on the subcarrier range of a 52-tone DRU, please refer to the relevant provisions in the protocols (such as 802.11ax / 802.11be), which will not be listed here.

[0129] In this embodiment of the application, the sum of the elements of the difference sequence corresponding to the 52-tone DRU is less than or equal to 2, which can make the LTF based on the 52-tone DRU have a lower PAPR.

[0130] Implementation Method 3: Long training sequences satisfy: z i This is the ratio of the sequence value corresponding to the i-th subcarrier among the subcarriers with an index less than 0 in a 26-tone DRU, to the sequence value corresponding to the i-th subcarrier among the subcarriers with an index greater than 0 in a 26-tone DRU. That is, z i This is the ratio of the sequence value corresponding to the i-th subcarrier of the negative half-frequency in the 26-tone DRU to the sequence value corresponding to the i-th subcarrier of the positive half-frequency in the same 26-tone DRU.

[0131] Sequence [z1,z2,z3,…,z] 13 This can be referred to as the difference sequence corresponding to 26-tone DRU. It can be called the sum of the elements of the difference sequence corresponding to the 26-tone DRU.

[0132] z iThis can be used to indicate whether the sequence value corresponding to the i-th subcarrier among the subcarriers with an index less than 0 in a 26-tone DRU is the same as the sequence value corresponding to the i-th subcarrier among the subcarriers with an index greater than 0 in the same 26-tone DRU. For example, z i A value of 1 indicates that the sequence value corresponding to the i-th subcarrier among the subcarriers with an index less than 0 in the 26-tone DRU is the same as the sequence value corresponding to the i-th subcarrier among the subcarriers with an index greater than 0 in the same 26-tone DRU. For example, z i A value of -1 indicates that the sequence value corresponding to the i-th subcarrier among the subcarriers with an index less than 0 in the 26-tone DRU is the opposite of the sequence value corresponding to the i-th subcarrier among the subcarriers with an index greater than 0 in the same 26-tone DRU.

[0133] Among some possible implementations, You can also replace the description with: or Among them, e i f is the sequence value corresponding to the i-th subcarrier among the subcarriers with an index less than 0 in a 26-tone DRU. i Let be the sequence value corresponding to the i-th subcarrier among the subcarriers with an index greater than 0 in a 26-tone DRU. For any 26-tone DRU, let the sequence values ​​corresponding to the 13 subcarriers contained in its negative half-frequency be [e1, e2, e3, ..., e...]. 13 Let the sequence values ​​corresponding to the 13 subcarriers contained in its positive half-frequency be [f1, f2, f3, ..., f 13 ], let [z1,z2,z3,…,z 13 ] = [e1 / f1,e2 / f2,e3 / f3,…,e 13 / f 13 ], or let [z1,z2,z3,…,z 13 ] = [f1 / e1,f2 / e2,f3 / e3,…,f 13 / e 13 ].

[0134] For example, the 26-tone DRU can be any 26-tone DRU corresponding to the discrete bandwidth. For instance, the 26-tone DRU can be any one of the 26-tone DRU1 to 26-tone DRU9 shown in Table 1. Or, the 26-tone DRU can be any one of the 26-tone DRU1 to 26-tone DRU18 shown in Table 2. That is, the sequence value corresponding to any 26-tone DRU within the discrete bandwidth satisfies:

[0135] For example, among the multiple 26-tone DRUs included in the discrete bandwidth, at least one 26-tone DRU satisfies: For example, a discrete bandwidth of 20MHz, comprising nine 26-tone DRUs, wherein at least one of the nine 26-tone DRUs satisfies:

[0136] For information on the subcarrier range of a 26-tone DRU, please refer to the relevant provisions in the protocol (such as 802.11ax / 802.11be), or refer to Table 1 or Table 2 for the subcarrier range of the 26-tone DRU. They are not listed here.

[0137] In this embodiment of the application, the sum of the elements of the difference sequence corresponding to the 26-tone DRU is less than or equal to 5, which can make the LTF based on the 26-tone DRU have a lower PAPR.

[0138] The above implementation methods one, two, and three can be combined. For example, this long training sequence satisfies: as well as At least one of the following. Regarding y i x i and z i The explanation can be found above, and will not be repeated here.

[0139] Implementation Method 4: Long training sequence is: LTF -128:127=[0 0 0 0 0 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 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 0 0 0 0 0 0 0]. The length of this long training sequence is 256. This long training sequence includes sequence values ​​corresponding to subcarriers with indices from -128 to 127. The sequence values ​​in this long training sequence correspond to subcarriers with indices from -128 to 127 in sequence.

[0140] Alternatively, this long training sequence can also be represented as: LTF -122:122=[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 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 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 The length of this long training sequence is 245. This long training sequence includes the sequence values ​​corresponding to the subcarriers with indices from -122 to 122, and the sequence values ​​corresponding to the subcarriers with other indices are 0.

[0141] Alternatively, this long training sequence can also be represented as: LTF -120:120=[-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 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 - ... The length of the long training sequence is 241. The long training sequence includes the sequence values ​​corresponding to the subcarriers with indices from -120 to 120, and the sequence values ​​corresponding to the subcarriers with other indices are 0.

[0142] In the embodiments of this application, the long training sequence may also have other representations, and this application does not limit the representation of the long training sequence.

[0143] With a discrete bandwidth of 20MHz, the sum of the elements of the difference sequence of each DRU corresponding to the long training sequence can be shown in Table 4, and the subcarrier range of each DRU can be shown in Table 1.

[0144] Table 4

[0145] As shown in Table 4, this long training sequence simultaneously satisfies: as well as That is, long training sequences satisfy the following: the absolute value of the sum of the elements of the difference sequence of any 26-tone DRU is less than or equal to 5, the absolute value of the sum of the elements of the difference sequence of any 52-tone DRU is less than or equal to 2, and the absolute value of the sum of the elements of the difference sequence of any 106-tone DRU is less than or equal to 5.

[0146] This long training sequence enables LTFs based on arbitrary DRU transmissions to achieve lower PAPR and better balance the transmit power of LTFs corresponding to 26-tone DRUs, 52-tone DRUs, and 106-tone DRUs. This ensures that the transmit power of the LTFs corresponding to each DRU (especially 52-tone and 106-tone DRUs) is kept away from the nonlinear region of the power amplifier. For example, with a discrete bandwidth of 20MHz, the PAPR of LTFs based on each DRU transmission is shown in Table 5.

[0147] Table 5

[0148] As shown in Table 5, the maximum PAPR value for each DRU is 4.68. In other words, the long training sequence provided in this application embodiment can make the PAPR of any DRU less than or equal to 4.68.

[0149] The design principles of the LTF sequence provided in the embodiments of this application are described below.

[0150] Both the sender and receiver can design LTF sequences according to the design principles described below. The designed LTF sequences may be the same as the long training sequences shown above (such as the long training sequences shown in Implementation Method 4 above), or they may be different from the long training sequences shown above. Alternatively, the sender and receiver may not execute the design principles described below, but instead directly store the LTF sequences designed according to the design principles described below. All LTF sequences designed according to the design principles described below fall within the protection scope of the embodiments of this application.

[0151] The design principle of LTF sequences is as follows: the absolute value of the sum of the elements of the difference sequence corresponding to any 26-tone DRU is less than or equal to 5, the absolute value of the sum of the elements of the difference sequence corresponding to any 52-tone DRU is less than or equal to 2, and the absolute value of the sum of the elements of the difference sequence corresponding to any 106-tone DRU is less than or equal to 5.

[0152] Based on the above design principles, the LTF sequence search process includes the following steps:

[0153] (1) Generate L first sequences, which include the sequence values ​​corresponding to the 13 subcarriers with indices less than 0 in the 26-tone DRU1. That is, the first sequence includes the sequence values ​​corresponding to the 13 subcarriers of the negative half-frequency of the 26-tone DRU1.

[0154] (2) According to A second sequence is determined, which includes the sequence values ​​corresponding to the 13 subcarriers with indices greater than 0 in the 26-tone DRU1. That is, the second sequence includes the sequence values ​​corresponding to the 13 subcarriers of the positive half-frequency of the 26-tone DRU1. Regarding z... i For further explanation, please refer to the relevant description above; it will not be elaborated upon here.

[0155] (3) The first and second sequences are spliced ​​together to obtain W1 sequences corresponding to 26-tone DRU1.

[0156] based on One first sequence can correspond to one or more second sequences, and 26-tone DRU1 can correspond to M sequences, all of which satisfy the following conditions: From these M sequences, select the W1 sequences with lower PAPR. When the DRU supports two spatial streams, for each sequence corresponding to the 26-tone DRU1, its PAPR is the maximum PAPR in the two spatial streams. The specific value of PAPR depends on the subcarrier range of the 26-tone DRU1 and the position of the pilot subcarriers.

[0157] With a discrete bandwidth of 20MHz, 20MHz contains 9 26-tone DRUs (26-tone DRU1 to 26-tone DRU9). The sequence search process for the other 26-tone DRUs can be referred to the sequence search process for the 26-tone DRU1, which will not be described in detail here. The number of sequences corresponding to 26-tone DRUi is denoted as Wi, i∈[1:9].

[0158] (4) Based on the sequence corresponding to 26-tone DRU1 and the sequence corresponding to 26-tone DRU2, determine the K1 sequences corresponding to 52-tone DRU1.

[0159] 52-tone DRU1 includes 26-tone DRU1 and 26-tone DRU2; in other words, 52-tone DRU1 can be viewed as a combination of 26-tone DRU1 and 26-tone DRU2. Therefore, the sequence corresponding to 52-tone DRU1 is also determined by the sequences corresponding to 26-tone DRU1 and 26-tone DRU2. For example, the sequence corresponding to 52-tone DRU1 is formed by concatenating the sequences corresponding to 26-tone DRU1 and 26-tone DRU2. Alternatively, the sequence corresponding to 52-tone DRU1 is formed by concatenating the sequence corresponding to 26-tone DRU1 after a -1 phase rotation with the sequence corresponding to 26-tone DRU2. Or, the sequence corresponding to 52-tone DRU1 is formed by concatenating the sequence corresponding to 26-tone DRU1 and the sequence corresponding to 26-tone DRU2 after a -1 phase rotation. The sequence corresponding to 52-tone DRU1 is obtained by splicing the sequences corresponding to 26-tone DRU1 and 26-tone DRU2 and then rotating the whole sequence by -1 phase.

[0160] For example, the sequence corresponding to 52-tone DRU1 can be represented as: [p*LTF 26-tone DRU1 q*LTF 26-tone DRU2 ], p = + / -1, q = + / -1. Where, LTF 26-tone DRU1 The sequence corresponding to 26-tone DRU1, LTF 26-tone DRU21 This is the sequence corresponding to 26-tone DRU2. The number of sequences corresponding to 26-tone DRU1 is W1, and the number of sequences corresponding to 26-tone DRU2 is W2. By concatenating the sequences corresponding to 26-tone DRU1 and 26-tone DRU2 using the methods described above, we can obtain W1*W2*4 sequences corresponding to 52-tone DRU1. Then, we select the sum of the elements of the difference sequences from these W1*W2*4 sequences. There are K1 sequences. All K1 sequences satisfy... Regarding x i For further explanation, please refer to the relevant description above; it will not be elaborated upon here.

[0161] With a discrete bandwidth of 20MHz, 20MHz includes four 52-tone DRUs (52-tone DRU1 to 52-tone DRU4). The sequences corresponding to the other 52-tone DRUs can be determined by the sequences of the two 26-tone DRUs they include. For specific implementation details, please refer to the specific implementation of the K1 sequences corresponding to 52-tone DRU1. These details will not be elaborated here.

[0162] (5) Based on the sequence corresponding to 52-tone DRU1 and the sequence corresponding to 52-tone DRU2, determine the sequence corresponding to 106-tone DRU1.

[0163] Since 106-tone DRU1 includes 52-tone DRU1, 52-tone DRU2, and two other subcarriers, the sequence corresponding to 106-tone DRU1 is formed by concatenating the sequences corresponding to 52-tone DRU1, 52-tone DRU2, and the sequence values ​​corresponding to the other two subcarriers. Alternatively, the sequence corresponding to 106-tone DRU1 is formed by concatenating the sequence corresponding to 52-tone DRU1 (after a -1 phase rotation), the sequence corresponding to 52-tone DRU2, and the sequence values ​​corresponding to the other two subcarriers. Alternatively, the sequence corresponding to 106-tone DRU1 is formed by concatenating the sequence corresponding to 52-tone DRU1, the sequence corresponding to 52-tone DRU2 (after a -1 phase rotation), and the sequence values ​​corresponding to the other two subcarriers. Alternatively, the sequence corresponding to 106-tone DRU1 is formed by concatenating the sequence corresponding to 52-tone DRU1, the sequence corresponding to 52-tone DRU2 (after a -1 phase rotation), and the sequence values ​​corresponding to the other two subcarriers. For example, 106-tone DRU1 can be represented as [r*LTF] 52-tone DRU1 s*LTF 52-tone DRU2 tu], where LTF 52-tone DRU1 The sequence corresponding to 52-tone DRU1, LTF 52-tone DRU2 The sequence corresponding to 52-tone DRU2 is r = + / -1, s = + / -1, and t and u are the other two subcarriers mentioned above, t = + / -1, u = + / -1.

[0164] The number of sequences corresponding to 52-tone DRU1 is K1, and the number of sequences corresponding to 52-tone DRU2 is K2. By concatenating one sequence corresponding to 52-tone DRU1 and one sequence corresponding to 52-tone DRU2 using the methods described above, we can obtain K1*K2*16 sequences. Then, we select sequences from K1*K2*16 sequences that satisfy the condition that the absolute value of the sum of the elements of the difference sequence of 106-tone DRU1 satisfies... From the Q sequences, select the one that minimizes the PAPR of the LTF, thus obtaining the sequence corresponding to 106-tone DRU1. Regarding y... i For detailed explanations, please refer to the relevant descriptions above; they will not be elaborated upon here.

[0165] For the search process of sequences corresponding to other 106-tone DRUs, please refer to the search process of sequences corresponding to 106-tone DRU1. It will not be described in detail here.

[0166] With a discrete bandwidth of 20MHz, the LTF sequence corresponding to 20MHz is determined by the sequences corresponding to two 106-tone DRUs and the sequence corresponding to 26-tone DRU 5. For example, the LTF sequence is formed by splicing the sequences corresponding to 106-tone DRU1, 106-tone DRU2, and 26-tone DRU 5.

[0167] With a discrete bandwidth of 40MHz, a 242-tone DRU can be formed by splicing the sequences corresponding to two 106-tone DRUs, and the LTF sequence corresponding to 40MHz is formed by splicing the sequences corresponding to two 242-tone DRUs.

[0168] With a discrete bandwidth of 80MHz, a 484-tone DRU can be formed by splicing the sequences corresponding to two 242-tone DRUs, and the LTF sequence corresponding to 80MHz is formed by splicing the sequences corresponding to two 284-tone DRUs.

[0169] The sequence search method provided in this application provides that the obtained LTF sequence satisfies the following condition: the absolute value of the sum of the elements of the difference sequence of any DRU is less than or equal to 5, thereby enabling the LTF corresponding to each DRU to have a low PAPR.

[0170] The following describes the communication device provided in the embodiments of this application.

[0171] This application divides the communication device into functional modules according to the above method embodiments. For example, each function can be divided into its own functional modules, or two or more functions can be integrated into one processing module. The integrated modules can be implemented in hardware or as software functional modules. It should be noted that the module division in this application is illustrative and only represents one logical functional division; other division methods may be used in actual implementation. The communication device of the embodiments of this application will be described in detail below with reference to Figures 5 to 7.

[0172] Figure 5 is a schematic diagram of a communication device provided in an embodiment of this application. As shown in Figure 5, the communication device includes a processing module 501 and a transceiver module 502. The transceiver module 502 can implement corresponding communication functions, and the processing module 501 is used to implement corresponding processing functions. For example, the transceiver module 502 can also be called an interface, a communication interface, or a communication module, etc.

[0173] In some embodiments of this application, the communication device can be used to perform the actions performed by the first station in the above method embodiments. In this case, the communication device can be the first station itself or a chip or functional module configurable in the first station. The transceiver module 502 is used to perform the transceiver-related operations of the first station in the above method embodiments, and the processing module 501 is used to perform the processing-related operations of the first station in the above method embodiments.

[0174] The processing module 501 is used to determine the long training sequence; the transceiver module 502 is used to send or output the long training field.

[0175] For a detailed explanation of the long training sequence and long training field, please refer to the above text; it will not be elaborated here.

[0176] Reusing Figure 5, in some other embodiments of this application, the communication device can be used to perform the actions performed by the second station in the above method embodiments. In this case, the communication device can be the second station itself or a chip or functional module configurable in the second station. The transceiver module 502 is used to perform the transceiver-related operations of the second station in the above method embodiments, and the processing module 501 is used to perform the processing-related operations of the second station in the above method embodiments.

[0177] The transceiver module 502 can be used to receive or input long training fields; the processing module 501 can be used to perform channel estimation based on the long training fields and long training sequences. For a detailed explanation of the long training sequences and long training fields, please refer to the above text; further details will not be provided here.

[0178] Optionally, in the above embodiments, the communication device may further include a storage module, which can be used to store instructions and / or data. The processing module 501 can read the instructions and / or data from the storage module to enable the communication device to implement the aforementioned method embodiments. For example, the storage module may store subcarrier planning, etc., as shown above.

[0179] For details regarding the specific explanations of each term, noun, or step in the above embodiments, please refer to the descriptions in the above method embodiments; they will not be detailed here.

[0180] The specific descriptions of the transceiver module and processing module shown in the above embodiments are merely examples. For the specific functions or execution steps of the transceiver module and processing module, please refer to the above method embodiments, which will not be described in detail here.

[0181] The communication device of this application embodiment has been described above. The following describes possible product forms of the communication device. Any product possessing the functions of the communication device described in FIG. 6 above falls within the protection scope of this application embodiment. The following description is merely illustrative and does not limit the product form of the communication device of this application embodiment to this.

[0182] In one possible implementation, in the communication device shown in FIG5, the processing module 501 can be one or more processors, and the transceiver module 502 can be a transceiver, or the transceiver module 502 can also be a transmitting module and a receiving module. The transmitting module can be a transmitter, and the receiving module can be a receiver. The transmitting module and the receiving module are integrated into one device, such as a transceiver. In the embodiments of this application, the processor and the transceiver can be coupled, etc., and the connection method of the processor and the transceiver is not limited in the embodiments of this application. In the process of executing the above method, the process of sending information in the above method can be the process of the processor outputting the above information. When outputting the above information, the processor outputs the above information to the transceiver so that the transceiver can transmit it. After the above information is output by the processor, it may need to undergo other processing before reaching the transceiver. Similarly, the process of receiving information in the above method can be the process of the processor receiving the input above information. When the processor receives the input information, the transceiver receives the above information and inputs it into the processor. Furthermore, after the transceiver receives the above information, the above information may need to undergo other processing before being input into the processor.

[0183] As shown in Figure 6, the communication device 60 includes one or more processors 620 and transceivers 610.

[0184] In some embodiments of this application, the communication device can be used to execute the steps, methods, or functions performed by the first station described above. For example, the processor 620 can be used to execute the functions or steps implemented by the processing module 501 shown in FIG. 5, and the transceiver 610 can be used to execute the functions or steps implemented by the transceiver module 502 shown in FIG. 5. Detailed descriptions of the processor 620 and transceiver 610 can be found in FIG. 5 or the method embodiments shown above, and will not be elaborated further here.

[0185] In other embodiments of this application, the communication device is used to execute the steps, methods, or functions performed by the second station described above. For example, the processor 620 can be used to execute the functions or steps implemented by the processing module 501 shown in FIG. 5, and the transceiver 610 can be used to execute the functions or steps implemented by the transceiver module 502 shown in FIG. 5. Detailed descriptions of the processor 620 and transceiver 610 can be found in FIG. 5 or the method embodiments shown above, and will not be elaborated further here.

[0186] In various implementations of the communication device shown in Figure 6, the transceiver may include a receiver for performing the function (or operation) of receiving, and a transmitter for performing the function (or operation) of transmitting. The transceiver is also used to communicate with other devices / appliances via a transmission medium.

[0187] Optionally, the communication device 60 may further include one or more memories 630 for storing program instructions and / or data. The memory 630 is coupled to the processor 620. The coupling in this embodiment is an indirect coupling or communication connection between communication devices, units, or modules, and can be electrical, mechanical, or other forms, used for information exchange between the communication devices, units, or modules. The processor 620 may operate in conjunction with the memory 630. The processor 620 may execute program instructions stored in the memory 630. Optionally, at least one of the above-mentioned memories may be included in the processor.

[0188] This embodiment does not limit the specific connection medium between the transceiver 610, processor 620, and memory 630. In Figure 6, the memory 630, processor 620, and transceiver 610 are connected via a bus 640, indicated by a thick line. The connection methods between other components are merely illustrative and not intended to be limiting. The bus can be an address bus, data bus, control bus, etc. For ease of illustration, only one thick line is used in Figure 6, but this does not indicate that there is only one bus or one type of bus.

[0189] In the embodiments of this application, the processor may be a general-purpose processor, a digital signal processor, an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc., and can implement or execute the various methods, steps, and logic block diagrams disclosed in the embodiments of this application. The general-purpose processor may be a microprocessor or any conventional processor. The steps of the methods disclosed in the embodiments of this application can be directly manifested as being executed by a hardware processor, or being executed by a combination of hardware and software modules within the processor.

[0190] In this application embodiment, the memory may include, but is not limited to, non-volatile memory such as hard disk drive (HDD) or solid-state drive (SSD), random access memory (RAM), erasable programmable read-only memory (EPROM), read-only memory (ROM), or compact disc read-only memory (CD-ROM), etc. Memory is any storage medium capable of carrying or storing program code having instruction or data structure forms, and capable of being read and / or written by a computer (such as the communication device shown in this application), but is not limited to this. The memory in this application embodiment may also be a circuit or any other device capable of implementing storage functions, used to store program instructions and / or data.

[0191] The processor 620 is primarily used to process communication protocols and data, control the entire communication device, execute software programs, and process the data from those programs. The memory 630 is primarily used to store software programs and data. The transceiver 610 may include control circuitry and an antenna. The control circuitry is primarily used for converting baseband signals to radio frequency signals and processing radio frequency signals. The antenna is primarily used for transmitting and receiving radio frequency signals in the form of electromagnetic waves. Input / output devices, such as touchscreens, displays, and keyboards, are primarily used to receive user input data and output data to the user.

[0192] When the communication device is powered on, the processor 620 can read the software program in the memory 630, 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 620 performs baseband processing on the data to be transmitted and outputs the baseband signal to the radio frequency (RF) circuit. The RF circuit then performs RF processing on the baseband signal and transmits the RF signal outward in the form of electromagnetic waves through the antenna. When data is sent to the communication device, the RF circuit receives the RF signal through the antenna, converts the RF signal into a baseband signal, and outputs the baseband signal to the processor 620. The processor 620 converts the baseband signal back into data and processes the data.

[0193] In another implementation, the radio frequency circuitry and antenna can be set up independently of the processor performing baseband processing. For example, in a distributed scenario, the radio frequency circuitry and antenna can be arranged remotely, independent of the communication device.

[0194] The communication device shown in this application embodiment may also have more components than those in Figure 6, and this application embodiment does not limit this. The methods executed by the processor and transceiver shown above are only examples, and the specific steps executed by the processor and transceiver can be referred to the methods described above.

[0195] In another possible implementation, in the communication device shown in Figure 5, the processing module 501 can be one or more logic circuits, and the transceiver module 502 can be an input / output interface, or a communication interface, or an interface circuit, or an interface, etc. Alternatively, the transceiver module 502 can also be a transmitting module and a receiving module. The transmitting module can be an output interface, and the receiving module can be an input interface. The transmitting module and the receiving module are integrated into one module, such as an input / output interface. As shown in Figure 7, the communication device shown in Figure 7 includes a logic circuit 701 and an interface 702. That is, the above-mentioned processing module 501 can be implemented using the logic circuit 701, and the transceiver module 502 can be implemented using the interface 702. Among them, the logic circuit 701 can be a chip, a processing circuit, an integrated circuit, or a system-on-a-chip (SoC) chip, etc., and the interface 702 can be a communication interface, an input / output interface, pins, etc. For example, Figure 7 uses the above-mentioned communication device as a chip, which includes the logic circuit 701 and the interface 702.

[0196] In this embodiment, the logic circuit and the interface can also be coupled to each other. The specific connection method of the logic circuit and the interface is not limited in this embodiment. For example, the logic circuit 701 can be used to execute the functions or steps implemented by the processing module 501 shown in FIG. 5, and the interface 702 can be used to execute the functions or steps implemented by the transceiver module 502 shown in FIG. 5. For a detailed description of the logic circuit 701 and the interface 702, please refer to FIG. 5 or the method embodiment shown above, which will not be detailed here.

[0197] The communication device shown in the embodiments of this application can implement the method provided in the embodiments of this application in hardware form, or it can implement the method provided in the embodiments of this application in software form, etc., and the embodiments of this application do not limit it in this way.

[0198] Furthermore, embodiments of this application also provide a communication system, which includes a first station and a second station, the first station and the second station being used to perform the methods in any of the foregoing embodiments.

[0199] This application also provides a computer program for implementing the operations and / or processes performed by various sites in the methods provided in this application.

[0200] This application also provides a computer-readable storage medium storing computer code that, when executed on a computer, causes the computer to perform operations and / or processes performed by various sites in the methods provided in this application.

[0201] This application also provides a computer program product comprising computer code or a computer program that, when run on a computer, causes the operations and / or processes performed by various sites in the method provided in this application to be executed.

[0202] In the embodiments provided in this application, it should be understood that the disclosed systems, communication devices, and methods can be implemented in other ways. For example, the communication device embodiments described above are merely illustrative. For instance, the division of modules is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple modules or components may be combined or integrated into another system, or some features may be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed may be indirect coupling or communication connection through some interfaces, communication devices, or modules, or it may be an electrical, mechanical, or other form of connection.

[0203] The modules described as separate components may or may not be physically separate. The components shown as modules may or may not be physical modules; that is, they may be located in one place or distributed across multiple network modules. Some or all of the modules can be selected according to actual needs to achieve the technical effects of the solutions provided in the embodiments of this application.

[0204] Furthermore, the functional modules in the various embodiments of this application can be integrated into one processing module, or each module can exist physically separately, or two or more modules can be integrated into one module. The integrated modules described above can be implemented in hardware or as software functional modules.

[0205] If the integrated module is implemented as a software functional module and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a readable storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned readable storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0206] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A communication method, characterized in that, include: Determine a long training sequence, wherein the long training sequence satisfies: y i The ratio of the sequence value corresponding to the i-th subcarrier among the subcarriers with an index less than 0 in the 106-tone DRU to the sequence value corresponding to the i-th subcarrier among the subcarriers with an index greater than 0 in the 106-tone DRU. Send a long training field, which is determined based on the long training sequence.

2. The method according to claim 1, characterized in that, The long training sequence also satisfies: x i The ratio of the sequence value corresponding to the i-th subcarrier among the subcarriers with an index less than 0 in the 52-tone DRU to the sequence value corresponding to the i-th subcarrier among the subcarriers with an index greater than 0 in the 52-tone DRU.

3. The method according to claim 1 or 2, characterized in that, The long training sequence also satisfies: z i It is the ratio of the sequence value corresponding to the i-th subcarrier among the subcarriers with an index less than 0 in the 26-tone DRU to the sequence value corresponding to the i-th subcarrier among the subcarriers with an index greater than 0 in the 26-tone DRU.

4. The method according to any one of claims 1-3, characterized in that, The subcarrier range of the 106-tone DRU is [-120:9:-12,6:9:114,-116:9:-8,10:9:118,-118:9:-10,8:9:116,-114:9:-6,12:9:120,-3,3]; or, The subcarrier range of the 106-tone DRU is [-119:9:-11,7:9:115,-115:9:-7,11:9:119,-117:9:-9,9:9:117,-113:9:-5,4:9:112,-2,2].

5. The method according to claim 2, characterized in that, The subcarrier range of the 52-tone DRU is: [-120:9:-12,6:9:114,-116:9:-8,10:9:118]; or, The subcarrier range of the 52-tone DRU is: [-118:9:-10, 8:9:116, -114:9:-6, 12:9:120]; or, The subcarrier range of the 52-tone DRU is: [-119:9:-11,7:9:115,-115:9:-7,11:9:119]; or, The subcarrier range of the 52-tone DRU is: [-117:9:-9,9:9:117,-113:9:-5,4:9:112].

6. The method according to any one of claims 1-5, characterized in that, The long training sequence is: [0 0 0 0 0 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 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 0 0 0 0 0 0 0]。 7. A communication method, characterized in that, include: Receive long training fields; Channel estimation is performed based on the long training field and the long training sequence, wherein the long training sequence satisfies: y i The ratio of the sequence value corresponding to the i-th subcarrier among the subcarriers with an index less than 0 in the 106-tone DRU to the sequence value corresponding to the i-th subcarrier among the subcarriers with an index greater than 0 in the 106-tone DRU.

8. The method according to claim 7, characterized in that, The long training sequence also satisfies: x i The ratio of the sequence value corresponding to the i-th subcarrier among the subcarriers with an index less than 0 in the 52-tone DRU to the sequence value corresponding to the i-th subcarrier among the subcarriers with an index greater than 0 in the 52-tone DRU.

9. The method according to claim 7 or 8, characterized in that, The long training sequence also satisfies: z i It is the ratio of the sequence value corresponding to the i-th subcarrier among the subcarriers with an index less than 0 in the 26-tone DRU to the sequence value corresponding to the i-th subcarrier among the subcarriers with an index greater than 0 in the 26-tone DRU.

10. The method according to any one of claims 7-9, characterized in that, The subcarrier range of the 106-tone DRU is [-120:9:-12,6:9:114,-116:9:-8,10:9:118,-118:9:-10,8:9:116,-114:9:-6,12:9:120,-3,3]; or, The subcarrier range of the 106-tone DRU is [-119:9:-11,7:9:115,-115:9:-7,11:9:119,-117:9:-9,9:9:117,-113:9:-5,4:9:112,-2,2].

11. The method according to claim 8, characterized in that, The subcarrier range of the 52-tone DRU is: [-120:9:-12,6:9:114,-116:9:-8,10:9:118]; or, The subcarrier range of the 52-tone DRU is: [-118:9:-10, 8:9:116, -114:9:-6, 12:9:120]; or, The subcarrier range of the 52-tone DRU is: [-119:9:-11,7:9:115,-115:9:-7,11:9:119]; or, The subcarrier range of the 52-tone DRU is: [-117:9:-9,9:9:117,-113:9:-5,4:9:112].

12. The method according to any one of claims 7-11, characterized in that, The long training sequence is: [0 0 0 0 0 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 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 0 0 0 0 0 0 0]。 13. A communication method, characterized in that, include: A long training sequence is determined, wherein the long training sequence is: [0 0 0 0 0 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 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 0 0 0 0 0 0 0]; Send a long training field, which is determined based on the long training sequence.

14. A communication method, characterized in that, include: Receive long training fields; Channel estimation is performed based on the long training field and the long training sequence, where the long training sequence is: [0 0 0 0 0 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 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 0 0 0 0 0 0 0 0].

15. A communication device, characterized in that, Includes a module for performing the method as described in any one of claims 1-14.

16. A communication device, characterized in that, The device includes at least one processor, which is configured to cause the communication device to implement the method as described in any one of claims 1-14.

17. A chip, characterized in that, It includes logic circuitry and an interface, the logic circuitry and the interface being coupled, the logic circuitry being configured to enable the chip to implement the method as described in any one of claims 1-14.

18. A computer-readable storage medium, characterized in that, The computer-readable storage medium is used to store a computer program, which, when executed by a computer, performs the method as described in any one of claims 1-14.

19. A computer program product, characterized in that, When the computer program product is executed by a computer, the method described in any one of claims 1-14 is performed.

20. A communication system, characterized in that, It includes a first site and a second site, wherein the first site is used to perform the method as described in any one of claims 1-6, and the second site is used to perform the method as described in any one of claims 7-12; or, the first site is used to perform the method as described in claim 13, and the second site is used to perform the method as described in claim 14.

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