Method for indicating physical layer configuration and related apparatus

Abstract

A transmitter generates a PPDU, the PPDU including a preamble field and an SFD field, where different values ​​of the preamble field or different values ​​of the SFD field correspond to different physical layer configurations; and the transmitter transmits the signal generated by the PPDU based on the physical layer configuration. According to an embodiment of the present application, the physical layer configuration can be flexibly indicated without increasing signaling overhead. This application is applicable to UWB-based WPAN systems, sensing systems, and the like that support 802.15 series protocols, such as the 802.15.4a protocol, the 802.15.4z protocol, or the 802.15.4ab protocol, and may further be applicable to WLAN systems that support 802.11 series protocols, such as next-generation Wi-Fi protocols such as 802.11ax, e.g., 802.11be, Wi-Fi 7, or EHT, and next-generation protocols of 802.11be, e.g., Wi-Fi 8.

Description

[Technical Field]

[0001] Book The application relates to the field of communication technology, and more particularly to a method for indicating the physical layer configuration and related apparatus. [Background technology]

[0002] Ultra-wideband (UWB) technology is a wireless carrier communication technology. For example, in UWB technology, data can be transmitted through narrow, non-sinusoidal pulses at the nanosecond level. Therefore, a wide spectral range is occupied. Because UWB has narrow pulses and low radiated spectral density, it has the advantages of high multipath resolution, low power consumption, and high security. With the introduction of ultra-wideband technology into the consumer sector, ultra-wideband wireless communication has become one of the physical layer technologies for short-range high-speed wireless networks and is mainly applied to sensing and ranging scenarios. The Institute of Electrical and Electronics Engineers (IEEE) has incorporated UWB technology into its IEEE 802 series of wireless standards and has released the high-speed wireless personal area network (WPAN) standards IEEE 802.15.4a and its advanced version IEEE 802.15.4z, which are based on UWB technology. The next-generation UWB wireless personal area network (WPAN) standard 802.15.4ab is being discussed.

[0003] In UWB technology, data is transmitted by sending and receiving extremely narrow pulses of less than nanoseconds, requiring high time synchronization between the transmitter and receiver. Furthermore, due to the wide communication bandwidth of UWB technology, transmitting and receiving signals over ultra-wideband channels results in high power consumption and increased device complexity. However, most UWB-based communication devices need to be battery-powered. Therefore, next-generation UWB wireless personal area network standards are expected to further reduce the power consumption of UWB systems. Thus, in next-generation UWB wireless personal area network standards, all signals except reference signals for ranging and sensing are received and transmitted through narrowband (NB) systems using narrowband signal-assisted methods, thereby reducing the power consumption overhead of UWB systems.

[0004] Currently, narrowband signals used to support UWB may have multiple physical layer configurations, and there are no instructions regarding different physical layer configurations. [Overview of the project] [Problems that the invention aims to solve]

[0005] Embodiments of the present invention provide a method for indicating physical layer configurations and related apparatus, which enable flexible indication of different physical layer configurations without increasing signaling overhead. [Means for solving the problem]

[0006] The present invention will be described below from different perspectives. Please understand that the following embodiments and the beneficial effects of these different perspectives will refer to one another.

[0007] According to a first aspect, the present invention provides a method for indicating a physical layer configuration. The method can be applied to narrowband in UWB systems. The method includes the following: A first communication device generates a physical layer protocol data unit (PPDU), the PPDU comprising a preamble field and a start-of-frame delimiter (SFD) field, where different values ​​of the SFD field correspond to different physical layer configurations, or different values ​​of the preamble field correspond to different physical layer configurations; the first communication device transmits a signal, the signal generated by the PPDU based on the physical layer configuration corresponding to the value of the SFD field or the value of the preamble field.

[0008] In this application, different values ​​in the SFD field or different values ​​in the preamble field indicate different physical layer configurations, thereby eliminating the need to change the PPDU format and allowing different physical layer configurations to be flexibly indicated without increasing signaling overhead.

[0009] In a second aspect, the present invention provides a method for indicating a physical layer configuration. This method may be applied to narrowband in UWB systems. The method includes the following: A second communication device receives a signal, demodulates the received signal to obtain a preamble field and an SFD field contained in the PPDU, where different values ​​of the SFD field correspond to different physical layer configurations, or different values ​​of the preamble field correspond to different physical layer configurations; the second communication device determines a physical layer configuration based on the value of the SFD field or the value of the preamble field; and based on the determined physical layer configuration, demodulates the received signal to obtain a payload field contained in the PPDU. It can be understood that the signal received by the second communication device is generated by the PPDU based on the physical layer configuration corresponding to the value of the preamble field or the SFD field in the PPDU.

[0010] In this application, different values ​​in the SFD field preceding the payload field or different values ​​in the preamble field represent different physical layer configurations, thereby allowing the received signal to be correctly demodulated and the payload field to be obtained.

[0011] In relation to the first or second aspect, in a possible implementation, the PPDU further includes a physical layer header (PHR) field and a payload field.

[0012] Optionally, a physical layer configuration includes one or more of the following parameters: data rate, length of the preamble field (which may be symbol length or bit length), length of the SFD field (which may be symbol length or bit length), length of the chip sequence corresponding to the preamble and SFD fields, length of the PHR field (which may be symbol length or bit length), and length of the chip sequence corresponding to the PHR and payload fields, or forward error correction (FEC) codes for the PHR and payload fields (including the type of FEC code for the PHR and payload fields, and whether FEC codes are used for the PHR and payload fields). For example, one value in the SFD field or one value in the preamble field corresponds to an index of a physical layer configuration, and one index identifies a physical layer configuration.

[0013] Optionally, the physical layer configuration includes the length of the chip sequence corresponding to the PHR field and the payload field. In this case, the PHR field includes indicator information to indicate whether the payload field has an FEC code. For example, the indicator information is located at bit 7 of the PHR field.

[0014] In this application, different values ​​in the SFD field or different values ​​in the preamble field indicate different lengths of the chip sequence corresponding to the PHR field and payload field, and then bit 7 of the PHR field indicates whether the payload field has an FEC code, thereby allowing different physical layer configurations to be flexibly indicated without increasing bit overhead.

[0015] In relation to the first or second aspect, in a possible implementation, one of the values ​​in the SFD field is 11100101. Similarly, one of the values ​​in the preamble field is either all 16 bits are 0 or all 32 bits are 0.

[0016] In this application, one of the values ​​in the SFD field or one of the values ​​in the preamble field is restricted to an existing value. This may result in better compatibility with legacy devices in the network.

[0017] In relation to the first or second aspect, in a possible implementation, the value of the SFD field does not include any of the following values: a value where the first four bits are 0000 and the last four bits are any value; a value where the last four bits are 0000 and the first four bits are any value; and a value where the eight bits are 00000000.

[0018] One function of the SFD field is to separate the preamble field and the PHR field in a PPDU. Currently, the preamble field uses data symbols that are all 0. Therefore, in this application, the values ​​in the SFD field do not include values ​​whose data symbols are 0, thereby reducing the possibility of confusion between the SFD field and the preamble field.

[0019] In relation to the first side or the second side, in one possible implementation, the value of the SFD field belongs to the first set of values, and the value of the preamble field is obtained by repeating the values within the first set of values one or more times. The first set of values may include M values, and the length of each value may be 8 bits. For the specific content included in the first set of values, refer to the description in the following method embodiments. Details are not described here.

[0020] Optionally, the M values in the first set of values satisfy the following condition. The sum of the Hamming distances between the chip sequences corresponding to any two of the M values is greater than or equal to the sum of the Hamming distances between the chip sequences corresponding to any two of any M values other than the first set of values within the second set of values. The second set of values includes N values, N is greater than M, and M may be greater than 2. Both N and M are positive integers. For example, N is 255 and M is equal to 5.

[0021] Optionally, the M values in the first set of values include a target value, and the target value is 11100101. The M values satisfy the following condition. The sum of the Hamming distances between the chip sequences corresponding to any two of the M values is greater than or equal to the sum of the Hamming distances between the chip sequences corresponding to any two of any M values that are outside the first set of values within the second set of values and include the target value. The second set of values includes N values, N is greater than M, and M may be greater than 2. Both N and M are positive integers.

[0022] When M is equal to 2, it can be understood that the Hamming distance between the chip sequences corresponding to these two values in the first set of values is greater than or equal to the Hamming distance between the chip sequences corresponding to any two values that include the target value and are outside the first set of values within the second set of values.

[0023] Optionally, M values ​​in the first set of values ​​satisfy one of the following conditions: The sum of the autocorrelation sidelobe amplitudes of the chip sequences corresponding to all of the M values ​​is less than or equal to the sum of the autocorrelation sidelobe amplitudes of the chip sequences corresponding to all of any M values ​​in the second set of values ​​other than those in the first set; or the sum of the cross-correlation sidelobe amplitudes between the chip sequences corresponding to any two of the M values ​​is less than or equal to the sum of the cross-correlation sidelobe amplitudes between the chip sequences corresponding to any two of the M values ​​in the second set of values ​​other than those in the first set. The second set of values ​​contains N values, where N is greater than M and M may be greater than 2. N and M are both positive integers.

[0024] When M is equal to 1, for the SFD field, the first set of values ​​can be understood to include the existing value 11100101 for the SFD field. When M is equal to 1, for the preamble field, the first set of values ​​includes the value 00000000.

[0025] According to a third aspect, one embodiment of the present application provides a communication device. The communication device is configured to perform a method according to either the first aspect or a possible implementation of the first aspect. The communication device includes a unit for performing a method according to either the first aspect or a possible implementation of the first aspect.

[0026] According to a fourth aspect, one embodiment of the present application provides a communication device. The communication device is configured to perform a method according to either the second aspect or a possible implementation of the second aspect. The communication device includes a unit for performing a method according to either the second aspect or a possible implementation of the second aspect.

[0027] In the third or fourth aspect, the communication device may include a transceiver unit and a processing unit. For a specific description of the transceiver unit and the processing unit, please refer to the device embodiments shown below. For the beneficial effects of the third and fourth aspects, please refer to the relevant descriptions of the first and second aspects. Further details are not described herein.

[0028] According to the fifth aspect, the present application provides a communication device. The communication device includes a processor configured to perform a method according to either the first aspect or a possible implementation thereof. Alternatively, the processor is configured to execute a program stored in memory. Once the program is executed, a method according to either the first aspect or a possible implementation thereof is performed.

[0029] In relation to the fifth aspect, in one possible implementation, the memory is located outside the communication device.

[0030] In relation to the fifth aspect, in one possible implementation, the memory is located inside the communication device.

[0031] In this application, the processor and memory may, alternatively, be integrated into a single component. In other words, the processor and memory can, alternatively, be integrated together.

[0032] In relation to the fifth aspect, in a possible implementation, the communication device further includes a transceiver, which is configured to transmit signals.

[0033] According to the sixth aspect, the present application provides a communication device. The communication device includes a processor configured to perform a method according to the second aspect or a possible implementation thereof. Alternatively, the processor is configured to execute a program stored in memory. Once the program is executed, a method according to the second aspect or a possible implementation thereof is performed.

[0034] In relation to the sixth aspect, in one possible implementation, the memory is located outside the communication device.

[0035] In relation to the sixth aspect, in one possible implementation, the memory is located inside the communication device.

[0036] In this application, the processor and memory may, alternatively, be integrated into a single component. In other words, the processor and memory can, alternatively, be integrated together.

[0037] In relation to the sixth aspect, in one possible implementation, the communication device further includes a transceiver, which is configured to receive signals.

[0038] According to the seventh aspect, the present invention provides a communication device. The communication device includes a logic circuit and an interface, the logic circuit being coupled to the interface. The logic circuit is configured to generate a PPDU, the PPDU including a preamble field and an SFD field, where different values ​​of the SFD field correspond to different physical layer configurations, or different values ​​of the preamble field correspond to different physical layer configurations, and the interface is configured to output a signal, the signal being generated by the PPDU based on the physical layer configuration corresponding to the value of the SFD field or the value of the preamble field.

[0039] According to the eighth aspect, the present invention provides a communication device. The communication device includes a logic circuit and an interface, the logic circuit being coupled to the interface. The interface is configured to accept a signal, which is generated by a PPDU based on a physical layer configuration corresponding to the value of a preamble field or an SFD field in the PPDU, the logic circuit is configured to demodulate the signal to obtain the preamble field and SFD field contained in the PPDU, where different values ​​of the SFD field correspond to different physical layer configurations, or different values ​​of the preamble field correspond to different physical layer configurations, the logic circuit is further configured to determine a physical layer configuration based on the value of the SFD field or the value of the preamble field, and to demodulate the signal based on the determined physical layer configuration to obtain the payload field contained in the PPDU.

[0040] According to the ninth aspect, the present application provides a computer-readable storage medium. The computer-readable storage medium is configured to store a computer program. When the computer program is executed on a computer, the method according to the first aspect or any one of the possible implementations of the first aspect is performed.

[0041] According to the tenth aspect, the present application provides a computer-readable storage medium. The computer-readable storage medium is configured to store a computer program. When the computer program is executed on a computer, the method according to the second aspect or one of the possible implementations of the second aspect is performed.

[0042] According to the eleventh aspect, one embodiment of the present application provides a computer program product, the computer program product comprising a computer program or computer code, wherein when the computer program or computer code is executed on a computer, a method according to the first aspect or one of the possible implementations thereof is performed.

[0043] According to the twelfth aspect, one embodiment of the present application provides a computer program product. The computer program product comprises a computer program or computer code, and when the computer program or computer code is executed on a computer, a method according to the second aspect or one of possible implementations of the second aspect is performed.

[0044] According to the thirteenth aspect, the present application provides a computer program. When the computer program is executed on a computer, the method according to the first aspect or one of the possible implementations of the first aspect is performed.

[0045] According to the fourteenth aspect, the present application provides a computer program. When the computer program is executed on a computer, the method according to the second aspect or one of the possible implementations of the second aspect is performed.

[0046] According to the fifteenth aspect, one embodiment of the present application provides a wireless communication system, the wireless communication system comprising a first communication device and a second communication device, the first communication device being configured to perform a method according to either the first aspect or a possible implementation thereof, and the second communication device being configured to perform a method according to either the second aspect or a possible implementation thereof.

[0047] For the technical effects achieved in the aforementioned aspects, please refer to each other or to the technical effects in the embodiments of the method described below. Further details will not be explained here. [Brief explanation of the drawing]

[0048] [Figure 1] This is a diagram showing the structure of a wireless communication system according to one embodiment of the present invention. [Figure 2] This is a diagram of another structure of a wireless communication system according to one embodiment of the present invention. [Figure 3]This is a diagram showing the PPDU format of an O-QPSK signal according to one embodiment of the present invention. [Figure 4] This is a diagram of the format of an SFD field according to one embodiment of the present invention. [Figure 5] 5a is a diagram of the format of the PHR field according to one embodiment of the present application. 5b is a diagram of another format of the PHR field according to one embodiment of the present application. [Figure 6] This is a diagram showing the modulation and diffusion procedure according to one embodiment of the present invention. [Figure 7] This is a schematic flowchart of a method for specifying the physical layer configuration according to one embodiment of the present invention. [Figure 8] This figure shows a simulation of the symbol error rate of SFD symbols and payload symbols according to one embodiment of the present invention. [Figure 9] Another figure illustrating the simulation of the symbol error rate of SFD symbols and payload symbols according to one embodiment of the present invention. [Figure 10] This is another schematic flowchart of a method for specifying the physical layer configuration according to one embodiment of the present invention. [Figure 11] 11a is a diagram of yet another format of the PHR field according to one embodiment of the present application. 11b is a schematic diagram of yet another format of the PHR field according to one embodiment of the present application. [Figure 12] This is a diagram showing the configuration of a communication device according to one embodiment of the present invention. [Figure 13] This is a diagram showing the configuration of a communication device 1000 according to one embodiment of the present invention. [Figure 14] This is a diagram showing another structure of a communication device according to one embodiment of the present invention. [Modes for carrying out the invention]

[0049] The following describes the technical solutions in the embodiments of this application with reference to the accompanying drawings. Certainly explain.

[0050] In this description, words such as “first” and “second” are used merely to distinguish different subjects and do not limit the quantity or order of execution. Furthermore, words such as “first” and “second” do not indicate a clear distinction. In addition, terms such as “includes” and “has,” and any other variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device comprising a set of steps or units is not limited to the listed steps or units, but may instead optionally include further steps or units not listed, or other steps or units specific to these processes, methods, products, or devices.

[0051] In this description, unless otherwise specified, " / " means "or". For example, A / B may mean A or B. The term "and / or" in this specification describes only the relational relationship between related objects and indicates that three relationships may exist. For example, A and / or B can represent the following three cases: A exists only, both A and B exist, or B exists only. Also, "one or more of the following items" or similar expressions refer to any combination of these items, including any combination of a single item or multiple items. For example, at least one of a, b, or c may mean a, b, c, a and b, a and c, b and c, or a, b and c, where a, b, and c may be singular or plural.

[0052] In this application, words such as “example” or “for example” are used to provide examples, illustrations, or explanations. Any embodiment or design described in this application using “example,” “in one example,” or “for example” should not be described as being preferable or having more advantages than another embodiment or design. Strictly speaking, the use of terms such as “example,” “in one example,” or “for example” is intended to specifically present the relevant concepts.

[0053] In this application, elements expressed in the singular form are intended to represent "one or more," and unless otherwise specified, do not represent "only one."

[0054] In the embodiments of this application, "B corresponding to A" indicates that there is a correspondence between A and B, and it can be understood that B may be determined based on A. However, it should be further understood that determining (or generating) B based on A does not mean that B is determined (or generated) based solely on A, but that B may also be determined (or generated) based on A and / or other information.

[0055] The technical solutions provided herein are applicable to WPANs based on UWB technology. For example, the methods provided herein are applicable to IEEE 802.15 series protocols, such as the 802.15.4a protocol, the 802.15.4z protocol, or the 802.15.4 ab protocol, or future generations of the UWB WPAN standard. Examples are not listed herein. The methods provided herein may be further applied to various communication systems, such as Internet of Things (IoT) systems, Vehicle to X (V2X) or Narrowband Internet of Things (NB-IoT) systems, and are applicable to devices in Vehicle to X, Internet of Things nodes, sensors in the Internet of Things, smart cameras, smart remotes, and smart water or electricity meters in smart homes, as well as sensors in smart cities. The methods provided in this application are further applicable to long-term evolution (LTE) frequency division duplex (FDD) systems, LTE time division duplex (TDD) systems, universal mobile telecommunications systems (UMTS), worldwide interoperability for microwave access (WiMAX) communication systems, LTE systems, 5th-generation (5G) communication systems, 6th-generation (6G) communication systems, and the like.

[0056] UWB (Ultra-Wide Band) technology is a new wireless communication technology. In UWB technology, data is transmitted via narrow, non-sinusoidal pulses at the nanosecond level, and modulation is performed on impulses with very steep rise and fall times. Therefore, UWB technology occupies a wide spectral range, and as a result, the signal has a bandwidth of gigahertz (GHz). The bandwidth used by UWB is typically higher than 1 GHz. UWB systems do not need to generate a sinusoidal carrier signal and can transmit impulse sequences directly. Therefore, UWB systems have a wide spectrum and low average power. UWB wireless communication systems have advantages such as strong multipath resolution capability, low power consumption, and high confidentiality. This facilitates coexistence with other systems, thereby improving spectral utilization and system capacity. In addition, for short-range communication applications, the transmission power of a UWB transmitter can typically be lower than 1 mW (milliwatt). Theoretically, interference generated from UWB signals is only equivalent to white noise. This facilitates a good coexistence between ultra-wideband (UWB) communication and existing narrowband (NB) communication. Therefore, UWB systems and narrowband (NB) communication systems can operate simultaneously without interfering with each other.

[0057] The methods provided herein may be implemented by communication devices in a wireless communication system. In a communication device, a device or chip that implements the functionality of a UWB system may be called a UWB module, and a device or chip that implements the functionality of a narrowband communication system may be called a narrowband communication module. The UWB module and the narrowband communication module may be different devices or chips. Of course, the UWB module and the narrowband communication module may, alternatively, be integrated into a single device or chip. The implementation of the UWB module and the narrowband communication module in a communication device is not limited to the embodiments of this application. The communication device in this application includes a UWB module and a narrowband communication module.

[0058] In this application, narrowband may be understood as being in relation to UWB. Any communication system operating with a bandwidth narrower than that of UWB may be called a narrowband communication system. Of course, the term narrowband communication system may have other meanings, and this is not limited to this application. However, the communication bandwidth of a narrowband communication system may be narrower than that of a UWB system. The communication bandwidth of a narrowband communication system may also be understood as typically that of an unlicensed national information infrastructure (UNII-3) and UNII-5. A UWB system has a total of 16 channels, numbered 0 through 15. The center frequency of channel 0 is 499.2 MHz and the bandwidth is 499.2 MHz, the center frequency of channel 1 is 3494.4 MHz and the bandwidth is 499.2 MHz, the center frequency of channel 2 is 3993.6 MHz and the bandwidth is 499.2 MHz, the center frequency of channel 3 is 4992.8 MHz and the bandwidth is 499.2 MHz, the center frequency of channel 4 is 3993.6 MHz and the bandwidth is 1331.2 MHz, the center frequency of channel 5 is 6489.6 MHz and the bandwidth is 499.2 MHz, the center frequency of channel 6 is 6988.8 MHz and the bandwidth is 499.2 MHz, the center frequency of channel 7 is 6489.6 MHz and the bandwidth is 1081.6 MHz, and channel The center frequency of channel 8 is 7448.0 MHz and the bandwidth is 499.2 MHz; the center frequency of channel 9 is 7987.2 MHz and the bandwidth is 499.2 MHz; the center frequency of channel 10 is 8486.4 MHz and the bandwidth is 499.2 MHz; the center frequency of channel 11 is 7987.2 MHz and the bandwidth is 1331.2 MHz; the center frequency of channel 12 is 8985.6 MHz and the bandwidth is 499.2 MHz; the center frequency of channel 13 is 9494.8 MHz and the bandwidth is 499.2 MHz; the center frequency of channel 14 is 9984.0 MHz and the bandwidth is 499.2 MHz; the center frequency of channel 15 is 9484.8 MHz and the bandwidth is 1354.97 MHz.

[0059] Embodiments of this application are described primarily by using WPAN as an example, but for example, networks used in the IEEE 802.15 series standards are used as examples for explanation. Those skilled in the art will readily understand that various aspects of this application can be extended to other networks using various standards or protocols, such as wireless local area networks (WLANs), Bluetooth® (a wireless standard similar to the IEEE 802.11 standard, mainly used in Europe), wide area networks (WANs), or other networks currently known or to be developed in the future. Thus, various aspects provided in this application are applicable to any suitable wireless network, regardless of coverage and wireless access protocol.

[0060] The methods provided herein may be implemented by communication devices in a wireless communication system. The communication devices may be devices in a UWB system. For example, communication devices may include, but are not limited to, communication servers, routers, switches, bridges, computers, and mobile phones that support UWB and narrowband communication technologies (such as Wi-Fi, Bluetooth®, or Zigbee®). In another example, communication devices may include user equipment (UE). User equipment may include various handheld devices, vehicle-mounted devices (e.g., cars or components installed in cars), wearable devices, IoT devices, computing devices, or other processing devices connected to wireless modems that support UWB and narrowband communication technologies (such as Wi-Fi, Bluetooth®, or Zigbee®). Examples are not enumerated herein. In yet another example, communication devices may include a central control point, such as a personal area network (PAN) or PAN coordinator. The PAN coordinator or PAN may be a mobile phone, an in-vehicle device, an anchor, a tag, a smart home, etc. In yet another example, the communication device may include a chip, which may be located in a communication server, router, switch, terminal device, etc. Examples are not listed herein. It can be understood that the foregoing description of the communication device is applicable to the first and second communication devices in this application.

[0061] In embodiments of the present application, the communication device may include a hardware layer, an operating system layer running above the hardware layer, and an application layer running above the operating system layer. The hardware layer includes hardware such as a central processing unit (CPU), a memory management unit (MMU), and memory (also called main memory). The operating system may be any one or more types of computer operating systems that perform service processing through processes, for example, a Linux® operating system, a Unix® operating system, an Android operating system, an iOS operating system, or a Windows® operating system. The application layer includes applications such as a browser, an address book, word processing software, and instant messaging software. In addition, the specific structure of the implementer of the method provided in embodiments of the present application is not particularly limited in embodiments of the present application. It is sufficient that communication can be performed according to the method provided in embodiments of the present application by executing a program that records the code of the method provided in embodiments of the present application.

[0062] For example, Figure 1 is a diagram of the structure of a wireless communication system according to an embodiment of the present invention. As shown in Figure 1, the wireless communication system has a star topology structure. In this structure, a central control node (e.g., the PAN coordinator in Figure 1) can perform data communication with one or more other devices. Figure 2 is a diagram of another structure of a wireless communication system according to an embodiment of the present invention. As shown in Figure 2, the wireless communication system has a peer-to-peer topology structure. In this structure, a central control node (e.g., the PAN coordinator in Figure 2) may perform data communication with one or more other devices, and other different devices may also perform data communication with each other. In Figures 1 and 2, both full-function devices and reduced-function devices can be understood as communication devices shown in the present invention. A full-function device is in relation to a reduced-function device. For example, a reduced-function device cannot be a PAN coordinator. As another example, compared to a full-function device, a reduced-function device may not have coordination capabilities or may have a lower communication rate than a full-function device. The PAN coordinator shown in Figure 2 is merely an example, and it should be understood that each of the other three fully functional devices shown in Figure 2 may also be used as a PAN coordinator. Examples are not shown individually in this specification. Furthermore, the fully functional and reduced-functional devices shown herein are merely examples of communication devices, and it should be further understood that any device capable of implementing the physical layer configuration instruction method provided herein falls within the scope of protection of this application.

[0063] To further reduce the power consumption overhead of UWB systems, the next-generation UWB WPAN standard 802.15.4ab suggests that offset-quadrature phase shift keying (O-QPSK) signals, as defined in Chapter 12 of the IEEE 802.15.4-2020 standard, may be used to support UWB in ranging and sensing. It can be understood that the O-QPSK signal in this application may be a signal acquired through O-QPSK modulation. It can also be understood that the O-QPSK signal is a narrowband signal.

[0064] Figure 3 shows the structure of the PPDU for an O-QPSK signal based on Chapter 12 of the IEEE 802.15.4-2020 standard. Figure 3 is a diagram of the format of the PPDU for an O-QPSK signal according to one embodiment of the present application. As shown in Figure 3, the PPDU for an O-QPSK signal includes, but is not limited to, the following fields: preamble, start-of-frame delimiter (SFD), physical layer header (PHR), and payload. The length of the preamble field is typically 2 or 4 bytes, and all bits of the preamble field are 0. The SFD field is typically 1 byte, and the value of the SFD field is fixed. As shown in Figure 4, bits 0 to 7 of the SFD field are fixed, such as 11100101. The PHR field has two lengths, namely 1 byte (equal to 8 bits) and 14 bits. Figure 5a is a diagram of the format of a PHR field according to one embodiment of the present invention. As shown in Figure 5a, the length of the PHR field is 1 byte, with the first 7 bits (bits 0-6) indicating the payload length (in bytes) and the last bit (bit 7) being reserved. Figure 5b is a diagram of another format of a PHR field according to one embodiment of the present invention. As shown in Figure 5b, the length of the PHR field is 14 bits, with bits 0-6 indicating the payload length (in bytes), bit 7 being reserved, and bits 8-13 being all 0 and used as padding. It can be understood that the padding in the PHR field may be used for convolutional coding.

[0065] The PPDU shown in Figure 3 can be used to generate a modulated signal through the modulation and spreading process shown in Figure 6. In Figure 6, O-QPSK modulation is used as an example. As shown in Figure 6, bit-to-symbol mapping is first performed on the binary data from the PPDU, followed by symbol-to-chip mapping. The resulting chips are then input to an O-QPSK modulator for O-QPSK modulation. Finally, a modulated signal is output. The modulated signal may be an O-QPSK signal, or an O-QPSK signal may be obtained by performing other processing on the modulated signal, such as oversampling. Every 4 bits are mapped to one data symbol, and each data symbol is mapped to one chip sequence. Here, the symbol-to-chip mapping process may be understood as a spreading process, or the bit-to-symbol and symbol-to-chip processes may be understood as spreading processes.

[0066] Currently, several possible physical layer configurations have been proposed for the O-QPSK signal used to support UWB. For example, Table 1 below shows five possible physical layer configurations for the O-QPSK modulation scheme, each physical layer configuration including several physical layer parameters specifically shown in the first row of Table 1 below.

[0067] [Table 1]

[0068] In Table 1, CL7 is a convolutional code with a restricted length of 7 and a polynomial of the form (133,171).

[0069] The transmitting end may generate and transmit an O-QPSK signal based on the physical layer configuration in Table 1 (i.e., the rows in Table 1) and the modulation and spreading process shown in Figure 6, and it can be understood that the receiving end needs to perform the reverse operation in Figure 6 to reconstruct the PPDU from the received signal in order to obtain the payload (i.e., data information) within the PPDU. However, while performing the reverse operation in Figure 6, the receiving end needs to know the physical layer configuration used by the transmitting end (e.g., the data rate and the length of the chip sequence corresponding to each field of the PPDU) in order to obtain the payload of the PPDU through correct demodulation. Therefore, the transmitting end needs to provide the receiving end with the physical layer configuration used by the transmitting end.

[0070] Embodiments of the present invention provide a method for indicating physical layer configurations and related apparatus. Different values ​​of the SFD field or different values ​​of the preamble field indicate different physical layer configurations, thereby allowing for flexible indication of different physical layer configurations without the need to increase additional signaling overhead and improving the demodulation performance of SFD symbols or preamble symbols.

[0071] The technical solutions provided in this application will be described in detail below with reference to more attached drawings.

[0072] To clearly illustrate the technical solutions of this Application, this Application is described by using multiple embodiments. For details, please refer to the description below. In this Application, unless otherwise specified, the same or similar parts of embodiments or implementations should be referenced to one another. In the embodiments and implementations / methods / implementation methods of this Application, unless otherwise specified or unless a logical conflict occurs, the terminology and / or descriptions are consistent and can be referenced to one another between different embodiments and between implementations / methods / implementation methods of embodiments. Technical features in different embodiments and implementations / methods / implementation methods of embodiments can be combined based on the logical relationships within the technical features to form new embodiments, implementations, methods, or implementation methods. The following implementations of this Application are not intended to limit the scope of protection of this Application.

[0073] The communication device in this application may support the 802.15.4ab standard or the next-generation standard of 802.15.4ab, and may support multiple standards such as 802.15.4a, 802.15.4-2011, 802.15.4-2015, 802.15.4-2020, and 802.15.4z, and may further support WLAN standards of the 802.11 family such as 802.11ax, 802.11ac, 802.11n, 802.11g, 802.11b, 802.11a, 802.11be, and the next-generation standard of 802.11be. [Examples]

[0074] Embodiment 1 Embodiment 1 of the present invention primarily describes extending the values ​​of the SFD field or the preamble field to illustrate different physical layer configurations.

[0075] Figure 7 is a schematic flowchart of a physical layer configuration instruction method according to one embodiment of the present invention. The first and second communication devices in this method may be any two devices capable of performing data transmission as shown in Figure 1 or Figure 2. As shown in Figure 7, the physical layer configuration instruction method includes, but is not limited to, the following steps.

[0076] S101: The first communication device generates a PPDU, which includes a preamble field and an SFD field, where different values ​​in the SFD field or different values ​​in the preamble field correspond to different physical layer configurations.

[0077] S102: The first communication device transmits a signal, which is generated by the PPDU based on a physical layer configuration corresponding to the value of the SFD field or the value of the preamble field.

[0078] In response, the second communication device receives the signal.

[0079] In some scenarios, the signal in the embodiments of the present invention may be a narrowband signal and may be used to support the UWB in applications such as ranging, sensing, and data transmission. The signal may provide initial synchronization information for the UWB and transfer data. For example, control information, synchronization information, or data for the UWB may be carried within the signal payload. The application of the signal in step S102 in the UWB is not limited to the embodiments of the present invention.

[0080] Optionally, the structure of a PPDU may be shown in Figure 3. A PPDU includes, but is not limited to, a preamble field, an SFD field, a PHR field, and a payload field. The length of the SFD field is 1 byte, i.e., 8 bits, and the length of the preamble field is 2 bytes (i.e., 16 bits) or 4 bytes (i.e., 32 bits).

[0081] In one possible implementation, different values ​​of the SFD field correspond to different physical layer configurations; in other words, one value of the SFD field corresponds to one physical layer configuration. The values ​​of the SFD field belong to a first set of values; in other words, the values ​​of the SFD field are values ​​within the first set of values. The first set of values ​​includes one or more values. For example, in this case, one value within the first set of values ​​may correspond to one physical layer configuration. Optionally, in this implementation, all bits of the preamble field may be 0. Of course, the preamble field may be set to a different value instead. Implementations of the preamble field are not limited to the embodiments of this application.

[0082] Since the length of the SFD field is 8 bits, it can be understood that the value of the SFD field can be understood as an 8-bit value, that is, the value of bits 0 to 7 (bits 0-7) of the SFD field.

[0083] In another possible implementation, different values ​​of the preamble field correspond to different physical layer configurations, or in other words, one value of the preamble field corresponds to one physical layer configuration. The value of the preamble field can be obtained by repeating a value in a first set of values ​​one or more times. For example, the first set of values ​​includes one or more values, and one value in the first set of values ​​can be used as one value of the preamble field after being repeated one or more times. Optionally, in this implementation, the value of the SFD field may be 11100101. Of course, the SFD field may be set to a different value instead. Implementations of the SFD field are not limited to the embodiments of this application.

[0084] Since the length of the preamble field is 16 bits or 32 bits, it can be understood that the value of the preamble field can be understood as a 16-bit or 32-bit value, i.e., the value of bits 0-15 or bits 0-31 of the preamble field.

[0085] In a possible implementation, the physical layer configuration may include one or more of the following parameters: data rate, length of the preamble field (which may be symbol length or bit length), length of the SFD field (which may be symbol length or bit length), length of the chip sequence corresponding to the preamble and SFD fields, length of the PHR field (which may be symbol length or bit length), length of the chip sequence corresponding to the PHR and payload fields, or forward error correction (FEC) codes for the PHR and payload fields (specifically, the type of FEC code for the PHR and payload fields, and whether or not FEC codes are used for the PHR and payload fields). For example, one value in the SFD field or one value in the preamble field may correspond to an index of a physical layer configuration. One index identifies one physical layer configuration.

[0086] In this embodiment of the present application, different values ​​in the SFD field or different values ​​in the preamble field indicate different physical layer configurations, thereby flexibly indicating different physical layer configurations without the need to change the PPDU format or increase bit overhead.

[0087] In another possible implementation, the physical layer configuration may include the lengths of the chip sequences corresponding to the PHR field and the payload field. Specifically, one value in the SFD field or one value in the preamble field corresponds to one length of the chip sequence, and the chip sequence is the chip sequence corresponding to the PHR field and the payload field. In this implementation, the PHR field further includes indicator information to indicate whether the payload field has an FEC code. For example, the indicator information may be located in bit 7 of the PHR field. When the physical layer configurations shown in Table 1 are used as examples, it can be understood that there are four lengths of the chip sequences corresponding to the PHR field and the payload field, and only the lengths of the chip sequences corresponding to the PHR field and the payload field are the same in configuration 2 (i.e., the third row in Table 1) and configuration 3 (i.e., the fourth row in Table 1). Thus, to distinguish configuration 2 from configuration 3, bit 7 of the PHR field indicates whether the payload field has an FEC code.

[0088] In this embodiment of the present application, different values ​​in the SFD field or different values ​​in the preamble field indicate different lengths of chip sequences corresponding to the PHR field and payload field, and bit 7 of the PHR field indicates whether the payload field has an FEC code, thereby flexibly indicating different physical layer configurations without increasing bit overhead.

[0089] Optionally, the first set of values ​​may be predefined, specified by a standard protocol, or determined by both the receiver and the transmitter through negotiation. The first set of values ​​may contain M values, each of which may be 8 bits long. M may be 2 or greater. For example, the M values ​​in the first set of values ​​may satisfy the following condition: The sum of the Hamming distances between chip sequences corresponding to any two of the M values ​​is greater than or equal to the sum of the Hamming distances between chip sequences corresponding to any two of the M values ​​in the second set other than those in the first set. In another example, the M values ​​in the first set of values ​​may satisfy any one of the following conditions: (1) The sum of the autocorrelation sidelobe amplitudes of the chip sequences corresponding to all M values ​​is less than or equal to the sum of the autocorrelation sidelobe amplitudes of the chip sequences corresponding to all any M values ​​in the second set of values ​​other than the first set of values, or (2) The sum of the crosscorrelation sidelobe amplitudes between the chip sequences corresponding to any two of the M values ​​is less than or equal to the sum of the crosscorrelation sidelobe amplitudes between the chip sequences corresponding to any two of the M values ​​in the second set of values ​​other than the first set of values.

[0090] The second set of values ​​contains N values, where N is greater than M, and both N and M are positive integers. For specific methods of selecting the first set of values, please refer to the explanation below. Further details are not provided here.

[0091] In information theory, the Hamming distance can be understood as the number of different values ​​(or different characters) at corresponding positions in two isolength sequences (or isolength strings). In other words, the Hamming distance is the number of sequence values ​​that need to be replaced when one sequence is converted to another. For example, the Hamming distance between 1011101 and 1001001 is 2.

[0092] In this application, "to define in advance" can be understood as "to define," "to define beforehand," "to set in advance," "to remember," "to remember in advance," "to negotiate in advance," "to construct in advance," "to solidify," "to preburn," etc.

[0093] Optionally, for better compatibility with conventional devices in the network, one of the values ​​in the SFD field may be 11100101. In other words, the first set of values ​​may include the value 11100101. Similarly, for the preamble field, one of the values ​​in the preamble field may have all bits set to 0. In other words, the first set of values ​​may include the value 00000000.

[0094] Optionally, after generating the PPDU, the first communication device may generate a signal (in this case a modulated signal is obtained) based on the physical layer configuration and PPDU corresponding to the value of the SFD field or preamble field in the PPDU, and transmit the signal. In other words, the signal is generated by the PPDU based on the physical layer configuration. For example, the first communication device may generate the signal according to the modulation and spreading process shown in Figure 6. Details are not described here. It can be understood that the modulation scheme in this embodiment of the Application may be O-QPSK modulation, or of course, another modulation scheme, such as QPSK modulation. Specific modulation schemes are not limited to the embodiments of the Application. It can be further understood that the number of physical layer configurations is not limited in this embodiment of the Application, and the number of physical layer configurations in different modulation schemes may differ.

[0095] S103: The second communication device demodulates the received signal and obtains the preamble field and SFD field contained in the PPDU.

[0096] S104: The second communication device determines the physical layer configuration based on the value of the SFD field or the value of the preamble field, demodulates the received signal based on the determined physical layer configuration, and obtains the payload field contained in the PPDU.

[0097] Optionally, the second communication device may perform processes such as demodulation (i.e., the reverse operation of modulation), chip-to-symbol mapping, and symbol-to-bit mapping on the received signal to obtain the preamble field and SFD field contained in the PPDU. For example, the second communication device may obtain the preamble field and SFD field by performing the reverse process of Figure 6. In Figure 6, O-QPSK modulation is used as an example, but it should be understood that in this embodiment of the present application, the modulation scheme is not limited to O-QPSK modulation and may alternatively be another modulation scheme, such as QPSK modulation. The five physical layer configurations shown in Table 1 are used as examples, and it should be further understood that the length of the chip sequence corresponding to the preamble field and SFD field is all 32 bits. Thus, the second communication device may obtain the preamble field and SFD field by performing the reverse process of Figure 6 based on the mapping relationship between the data symbol and the 32-bit chip sequence.

[0098] A second communication device may further determine the physical layer configuration based on the value of the SFD field or the value of the preamble field, and demodulate the received signal based on the determined physical layer configuration (e.g., data rate, symbol length of the PHR field, length of the chip sequence corresponding to the PHR field and payload field, and FEC code for the PHR field and payload field) to obtain the payload field contained in the PPDU.

[0099] As shown in Table 1, it can be understood that the length of the chip sequence corresponding to the PHR field is variable. If the PHR field needs to be acquired through correct demodulation, the physical layer configuration must be indicated before the PHR field. In addition, the length of the PHR field in the PPDU shown in Figure 3 is limited and there are no spare bits to indicate multiple different physical layer configurations. Therefore, in this embodiment of the present application, different values ​​of the SFD field or different values ​​of the preamble field prior to the PHR field indicate different physical layer configurations, thereby allowing different physical layer configurations to be indicated flexibly without increasing signaling overhead.

[0100] The following describes, with the use of examples, the first set of values ​​and the manner in which the first set of values ​​is selected in this embodiment of the present application.

[0101] For example, possible ways of selecting the first set of values ​​are as follows:

[0102] Step (1): Initialization.

[0103] Since the length of the SFD field (in bits) is 8 bits, the possible values ​​of the SFD field are 2 8 (That is, 256) values. For the sake of clarity, all possible values ​​in the SFD field are denoted as the second set of values. In this case, N is equal to 256.

[0104] Since every 4 bits is mapped to one data symbol, an SFD field can be represented by two data symbols. The following shows all possible values ​​of an SFD field using data symbols (in other words, the second set of values ​​is represented as follows by using data symbols): x0=[0,0], x1=[0,1], x2=[0,2], ..., x 16 =[1,0], x 17 =[1,1], ..., and x 255 =[15,15]. x0~x 255It can be understood that 0 to 15 in this context represent data symbols 0 to 15, respectively. Data symbol 0 is 0000 when mapped to bits, data symbol 1 is 1000 when mapped to bits, data symbol 2 is 0100 when mapped to bits, data symbol 3 is 1100 when mapped to bits, and the rest can be inferred by analogy, and it can be further understood that data symbol 15 is 1111 when mapped to bits.

[0105] Next, S is set to an empty set, i.e., S = {φ}. M is set to represent the number of values ​​required, i.e., the number of physical layer configurations. It can be understood that M is also the number of values ​​in the first set of values. For example, Table 1 is used as an example, and M is equal to 5. It can be understood that as the number of physical layer configurations increases, the value of M also increases accordingly. The value of M is not limited to the embodiments of this application.

[0106] Step (2): Cyclical sequential iteration

[0107] For i=0, S=S∪{x i Let's assume}. Here, "∪" represents the union. Whenever i is set to a certain value, the following action is performed: If |S| ≤ M and i < 255, then i = i + 1; If |S|>M and i<255, then one value is removed from S so that the sum of the Hamming distances between any two chip sequences corresponding to any two values ​​in the remaining M values ​​in S is maximized, then i=i+1; or If |S|>M and i=255, then one value is removed from S so that the sum of the Hamming distances between chip sequences corresponding to any two values ​​in the remaining M values ​​in S is maximized, and then the result is output, i.e., step (3) is performed.

[0108] Here, |S| represents the number of values ​​in S (i.e., the number of x). It can be understood that each data symbol in the SFD field is mapped to a chip sequence of length 32. See the explanation below for the mapping relationship between data symbols and chip sequences. Details are not explained here.

[0109] Step 3: Output the results.

[0110] The remaining M values ​​in S can be used as the first set of values. Of course, some of the remaining values ​​in S may also be used as the first set of values.

[0111] The length of the preamble field (in bits) can be 16 bits or 32 bits, which can be understood as twice or four times the length of the SFD field (in bits). Therefore, the values ​​selected in steps (1), (2), and (3) for the first set of values ​​can be used as the values ​​of the preamble field after being repeated two or four times. The values ​​of the SFD field may be values ​​within the first set of values ​​and do not need to be repeated.

[0112] When M is greater than 2 and less than or equal to 256, it can be understood that the first set of values ​​can be obtained through steps (1) to (3). When M is equal to 2, the cyclic sequential iteration condition in step (2) may be as follows: If |S| ≤ M and i < 255, then i = i + 1; if |S| > M and i < 255, then one value is removed from S so as to maximize the Hamming distance between the chip sequences corresponding to the remaining two values ​​in S, then i = i + 1; or if |S| > M and i = 255, then one value is removed from S so as to maximize the Hamming distance between the chip sequences corresponding to the remaining two values ​​in S, then the result is output, i.e., step (3) is performed. When M is equal to 1, the first set of values ​​has only one value. For the SFD field, when M is equal to 1, the first set of values ​​includes the existing value 11100101 for the SFD field, which is represented as [7,10] by using data symbols. For the preamble field, when M is equal to 1, the first set of values ​​may include the value 00000000, which is represented as [0,0] by using data symbols.

[0113] Currently, it can be understood that the preamble field uses all-zero data symbols, and one function of the SFD field is used to separate the preamble field and the PHR field within the PPDU. Therefore, the value of the SFD field may need to avoid using the data symbol 0 to reduce the possibility of confusion between the SFD field and the preamble field. In other words, for the SFD field, the first set of values may not include any value where the data symbol is 0. For example, for the SFD field, the first set of values may not include any of the following (represented by data symbols): [0,0],[0,1],[0,2],[0,3],[0,4],[0,5],[0,6],[0,7],[0,8],[0,9],[0,10],[0,11],[0,12],[0,13],[0,14],[0,15],[1,0],[2,0],[3,0],[4,0],[5,0],[6,0],[7,0],[8,0],[9,0],[10,0],[11,0],[12,0],[13,0],[14,0],[15,0]. If the value of the SFD field needs to avoid using the data symbol 0, it can be understood that the loop condition in step (2) (i.e., assuming S = S{x i} for i = 0, 1, 2,..., 255) can be changed as follows: for i = 0, 1, 2,..., 255, if x i does not include the data symbol 0, assume S = S{x i}, or if x i includes the data symbol 0, then i = i + 1, that is, the next x i is selected. Of course, the loop sequential iteration in step (2) may be executed after the values including the data symbol 0 are removed from all possible values of the SFD field (i.e., the second set of values) in step (1).

[0114] Similarly, the current value of the SFD field is 11100101, which is represented as [7,10] by using data symbols. Therefore, to reduce the possibility of confusion between the SFD field and the preamble field, the use of the same values ​​as the SFD field should also be avoided in the preamble field values; that is, the use of data symbols 7 and 10 should be avoided in the preamble field values. For example, for the preamble field, the first set of values ​​does not have to include either of the following (represented by data symbols), namely [7,10] and [10,7].

[0115] For the SFD field, it can be understood that one value in S output in step (3) corresponds to one physical layer configuration. For example, Table 1 is used as an example. There are a total of five physical layer configurations, and M=5 may be set. For the SFD field, the five values ​​in S each correspond to one of the five physical layer configurations. The specific corresponding rules are not limited to the embodiments of the present application. For example, if the first set of values ​​includes an existing value in the SFD field (i.e., 11100101, represented as [7,10] by using data symbols), then the existing value in the SFD field may represent configuration #1 in Table 1 (i.e., the second row in Table 1). Similarly, if the first set of values ​​includes the value 00000000, which is represented as [0,0] by using data symbols, then existing values ​​in the preamble field (i.e., 16 bits all 0 or 32 bits all 0, i.e., 00000000 in the first set of values ​​being repeated two or four times) can represent configuration #1 in Table 1 (i.e., the second row in Table 1). This may be better compatible with conventional devices (e.g., traditional Zigbee devices).

[0116] In step (2), it can be understood that the Hamming distance between the corresponding chip sequences for each pair of values ​​in the set S is optimized to remove redundant values ​​in S. In step (2), redundant values ​​in the set S may be removed in other ways. For example, redundant values ​​in S may be removed by optimizing the autocorrelation or cross-correlation obtained by mapping different values ​​in S to chip sequences and then modulating them (e.g., O-QPSK modulation or QPSK modulation). Alternatively, redundant values ​​in S can be removed by optimizing the autocorrelation or cross-correlation obtained by mapping different values ​​in S to chip sequences and then modulating them (e.g., O-QPSK modulation or QPSK modulation) and then oversampling. For example, the value with the largest autocorrelation sidelobe amplitude in S may be removed, or the value with the largest normalized autocorrelation sidelobe amplitude in S (e.g., the autocorrelation peak amplitude is used as the normalization denominator) may be removed, or the value with the largest average autocorrelation sidelobe amplitude in S may be removed. In another example, one value may be removed from S such that the sum of the cross-correlation sidelobe amplitudes between chip sequences corresponding to every two of the remaining M values ​​in S, or the mean value of the cross-correlation sidelobe amplitudes, or the maximum cross-correlation sidelobe amplitude is minimized. In yet another example, one value may be removed from S such that the normalized cross-correlation sidelobe amplitude between chip sequences corresponding to every two of the remaining M values ​​in S (for example, with the autocorrelation peak amplitude used as the normalized denominator) is minimized, or the mean value of the normalized cross-correlation sidelobe amplitudes is minimized.

[0117] For a fixed M, it can be understood that multiple sets of values ​​may be selected through cyclic sequential iterations in step (2). For example, multiple sets of values ​​may satisfy the following conditions: multiple sets of values ​​(each set containing M values) have the same sum of Hamming distances that is greater than the sum of the Hamming distances of the other M values; or multiple sets of values ​​(each set containing M values) have the same sum of normalized autocorrelation sidelobe amplitudes that is smaller than the sum of the normalized autocorrelation sidelobe amplitudes of the other M values; or multiple sets of values ​​(each set containing M values) have the same sum of normalized cross-correlation sidelobe amplitudes that is smaller than the sum of the normalized cross-correlation sidelobe amplitudes of the other M values ​​(e.g., the autocorrelation peak amplitude is used as the normalization denominator).

[0118] The following examples illustrate some or all sets of values ​​selected by using steps (1) to (3) based on different mapping tables from data symbols to 32-bit chip sequences.

[0119] In one example, by using steps (1) to (3), some or all sets of values ​​for the SFD field, selected based on the data symbol to chip sequence mapping table shown in Table 2 below, are shown in Tables 3 and 4 below. Any set of values ​​shown in Table 4 includes the existing value 11100101 for the SFD field.

[0120] It can be understood that the first set of values ​​in this embodiment of the present application may include any M values ​​in Tables 3 and / or 4 below, the value of the SFD field may be selected from the first set of values, and the value of the preamble field may be obtained by repeating the values ​​in the first set of values ​​once or more times.

[0121] [Table 2]

[0122]

Table 3

[0123]

Table 4

[0124] In another example, by using steps (1) to (3), some or all sets of values ​​for the SFD field, selected based on the mapping table from data symbols to chip sequences shown in Table 5 below, are shown in Tables 6 and 7 below. Any set of values ​​shown in Table 7 includes the existing value 11100101 for the SFD field.

[0125] It can be understood that the first set of values ​​in this embodiment of the present application may include any M values ​​in Tables 6 and / or 7 below, the value of the SFD field may be selected from the first set of values, and the value of the preamble field may be obtained by repeating the values ​​in the first set of values ​​once or more times.

[0126] [Table 5]

[0127] [Table 6] TIFF0007855790000031.tif248170 TIFF0007855790000032.tif250170 TIFF0007855790000033.tif251170 TIFF0007855790000034.tif248170 TIFF0007855790000035.tif250170 TIFF0007855790000036.tif249170 TIFF0007855790000037.tif247170 TIFF0007855790000038.tif249170 TIFF0007855790000039.tif247170 TIFF0007855790000040.tif246170 TIFF0007855790000041.tif133170

[0128] [Table 7] TIFF0007855790000043.tif249170 TIFF0007855790000044.tif246170 TIFF0007855790000045.tif247170 TIFF0007855790000046.tif247170 TIFF0007855790000047.tif247170 TIFF0007855790000048.tif248170 TIFF0007855790000049.tif246170 TIFF0007855790000050.tif247170 TIFF0007855790000051.tif99170

[0129] In yet another example, by using steps (1) to (3), some or all sets of values ​​for the SFD field, selected based on the mapping table from data symbols to chip sequences shown in Table 8 below, are shown in Tables 9 and 10 below. Any set of values ​​shown in Table 10 includes the existing value 11100101 for the SFD field.

[0130] It can be understood that the first set of values ​​in this embodiment of the present application may include any M values ​​in Tables 9 and / or 10 below, the value of the SFD field may be selected from the first set of values, and the value of the preamble field may be obtained by repeating the values ​​in the first set of values ​​once or more times.

[0131] [Table 8]

[0132] [Table 9] TIFF0007855790000054.tif250170 TIFF0007855790000055.tif249170 TIFF0007855790000056.tif247170 TIFF0007855790000057.tif248170 TIFF0007855790000058.tif248170 TIFF0007855790000059.tif246170 TIFF0007855790000060.tif248170 TIFF0007855790000061.tif247170 TIFF0007855790000062.tif248170 TIFF0007855790000063.tif248170 TIFF0007855790000064.tif248170 TIFF0007855790000065.tif248170 TIFF0007855790000066.tif247170 TIFF0007855790000067.tif247170 TIFF0007855790000068.tif218170

[0133]

Table 10

[0134] In yet another example, unlike the data symbol-to-chip sequence mapping tables shown in Tables 2, 5, and 8, the Hamming distance between any two chip sequences is 16 in the data symbol-to-chip sequence mapping table shown in Table 11 below. Therefore, it is not possible to select the required set of values ​​by constraining the Hamming distance. In this case, the appropriate set of values ​​can be selected by constraining the autocorrelation sidelobe amplitude or cross-correlation sidelobe amplitude. Also, for the SFD field, values ​​containing data symbol 0 can be excluded. Specifically, in step (2), redundant values ​​in S can be removed by optimizing the autocorrelation or cross-correlation obtained by mapping different values ​​in S to chip sequences and then performing modulation (e.g., O-QPSK modulation or QPSK modulation). Alternatively, redundant values ​​in S can be removed by optimizing the autocorrelation or cross-correlation obtained by mapping different values ​​in S to chip sequences and then performing modulation (e.g., O-QPSK modulation or QPSK modulation) and then performing oversampling. For example, the value with the largest autocorrelation sidelobe amplitude in S may be removed, or the value with the largest normalized autocorrelation sidelobe amplitude in S (e.g., autocorrelation peak amplitude is used as the normalization denominator), or the value with the largest average autocorrelation sidelobe amplitude in S may be removed. In another example, one value may be removed from S so as to minimize the sum of the cross-correlation sidelobe amplitudes between chip sequences corresponding to every two of the remaining M values ​​in S, or the mean value of the cross-correlation sidelobe amplitudes, or the maximum cross-correlation sidelobe amplitude. In yet another example, one value may be removed from S so as to minimize the normalized cross-correlation sidelobe amplitudes between chip sequences corresponding to every two of the remaining M values ​​in S (e.g., autocorrelation peak amplitude is used as the normalization denominator), or the mean value of the normalized cross-correlation sidelobe amplitudes.

[0135] [Table 11]

[0136] In this embodiment of the present application, different values ​​of the SFD field or different values ​​of the preamble field indicate different physical layer configurations, thereby allowing for flexible configuration of the narrowband physical layer without requiring additional instructions and thereby reducing overhead. For example, for Table 3, it is assumed that M=5 (including data symbol 0), and the correspondence between the five values ​​of the SFD field and the five physical layer configurations is shown in Table 12 below. The correspondence between the values ​​of the SFD field and the physical layer configurations is not limited to the embodiments of the present application; it is merely an example for illustrative purposes in this specification.

[0137] [Table 12]

[0138] Config 1 to Config 5 in Table 12 can represent five different physical layer configurations. For example, Config 1 to Config 5 in Table 12 may represent the five physical layer configurations (O-QPSK modulation) in Table 1. It should be understood that the SFD field values ​​and the number of physical layer configurations shown in Table 12 are merely examples. In actual applications, the number of physical layer configurations may differ for different modulation schemes. Correspondingly, the number of SFD field values ​​changes with the number of physical layer configurations (for example, the number of SFD field values ​​is equal to the number of physical layer configurations). For example, suppose the number of physical layer configurations in a modulation scheme is K. The number of SFD field values ​​may also be K. The SFD field values ​​may be any K value in Tables 3 and 4, Tables 6 and 7, or Tables 9 and 10. Specific modulation schemes and specific physical layer configurations are not limited to the embodiments of this application.

[0139] In addition, for better explanation, the different values ​​of the SFD field in this embodiment of the present application represent the performance of different physical layer configurations. The following shows the simulation results of the symbol error rate for SFD symbols and payload symbols.

[0140] For example, Figure 8 shows a simulation of the symbol error rate of SFD symbols and payload symbols according to one embodiment of the present invention. The SFD symbols used in the simulation process are the data symbols when M=5 (including data symbol 0) in Table 3, and the payload symbols used in the simulation process are the data symbols in Table 2, with a payload length of 127 bytes for each data packet. The simulation channel is an additive white Gaussian noise channel.

[0141] Figure 8 shows the symbol error rate performance of SFD symbols and payload symbols on an additive white Gaussian noise channel. In Figure 8, the horizontal axis represents the power ratio of each bit to background noise (in dB), and the vertical axis represents the symbol error rate at the receiving end. From Figure 8, for the same symbol error rate, for example, a symbol error rate of 10 -3 When this is the case, the SFD symbol has a lower bit-to-background noise power ratio, which indicates that the demodulation performance of the SFD symbol is better than that of the payload symbol. In other words, in this embodiment of the present application, the demodulation performance of the SFD symbol or preamble symbol can be further improved.

[0142] As another example, another possible mode of selecting the first set of values ​​to further improve performance is as follows:

[0143] Step (1): Initialization. Data symbols are still used to represent all possible values ​​in an SFD field (in other words, the second set of values ​​is represented by using data symbols): x0=[0,0], x1=[0,1], x2=[0,2], ..., x 16 =[1,0], x 17 =[1,1], ..., x 255 =[15,15]. x0~x 255 It can be understood that 0 to 15 in this case represent data symbols 0 to 15, respectively. Data symbol 0 is mapped to bits 0000, data symbol 1 is mapped to bits 1000, data symbol 2 is mapped to bits 0100, data symbol 3 is mapped to bits 1100, and the rest can be inferred by analogy, and it can be further understood that data symbol 15 is mapped to bits 1111.

[0144] Step (2): Remove data symbol 0. Values ​​containing the data symbol 0 are excluded from all possible values ​​in the SFD field. In this case, the SFD field has 256 - 16 - 16 + 1 = 225 possible values.

[0145] Step 3: Maximize the minimum humming distance. Out of the 225 possible values ​​in the SFD field, M-1 values ​​are selected, and the value x is supported by the existing standard. 121 A set is formed with =[7,10]. The Hamming distance is calculated by mapping any two values ​​in this set to the chip. In this case, there are a total of M*(M-1) / 2 Hamming distances. The M-1 values ​​are selected from 225 possible values, and the M-1 values ​​and the value x 121 The minimum value of M*(M-1) / 2 Hamming distances in the set including =[7,10] is the value x of any other M-1 values ​​in the 225 possible values. 121The values ​​are selected using a traverse method such that they are greater than or equal to the minimum value of M*(M-1) / 2 Hamming distances in the set including =[7,10].

[0146] Step (4): Maximize the sum of the Hamming distances. Based on step (3), the Hamming distances obtained by mapping two values ​​in the set to the chip are calculated, resulting in a total of M*(M-1) / 2 Hamming distances. From one or more sets obtained in step (3), the set that maximizes the sum of M*(M-1) / 2 Hamming distances is selected as the first set of values.

[0147] For example, in the aforementioned embodiment for selecting a first set of values, some or all of the sets of values ​​for the SFD fields selected based on the mapping table from data symbols to chip sequences shown in Table 2 are shown in Table 13 below. Table 13 below shows the values ​​of the SFD fields and an example of the physical layer configuration corresponding to those values. Physical layer configuration #1 in Table 13 below can only be indicated by the SFD field value being 11100101, and it can be understood that the correspondence between the remaining physical layer configurations and the remaining values ​​in the first set of values ​​other than 11100101 may be randomly combined.

[0148] [Table 13] TIFF0007855790000086.tif247170 TIFF0007855790000087.tif248170 TIFF0007855790000088.tif249170 TIFF0007855790000089.tif247170 TIFF0007855790000090.tif247170 TIFF0007855790000091.tif247170 TIFF0007855790000092.tif247170 TIFF0007855790000093.tif245170 TIFF0007855790000094.tif246170 TIFF0007855790000095.tif248170 TIFF0007855790000096.tif248170 TIFF0007855790000097.tif247170 TIFF0007855790000098.tif249170 TIFF0007855790000099.tif246170 TIFF0007855790000100.tif246170 TIFF0007855790000101.tif247170 TIFF0007855790000102.tif248170 TIFF0007855790000103.tif247170 TIFF0007855790000104.tif248170 TIFF0007855790000105.tif247170 TIFF0007855790000106.tif246170 TIFF0007855790000107.tif248170 TIFF0007855790000108.tif248170 TIFF0007855790000109.tif249170 TIFF0007855790000110.tif249170 TIFF0007855790000111.tif247170 TIFF0007855790000112.tif125170

[0149] For better explanation, the different values ​​of the SFD field in Table 13 represent the performance of different physical layer configurations. The following shows the simulation results of the symbol error rate for SFD symbols and payload symbols.

[0150] For example, Figure 9 is another diagram of a simulation of the symbol error rate of SFD symbols and payload symbols according to one embodiment of the present application. The SFD symbols used in the simulation process are data symbols when the SFD group number in Table 13 is 1, and the payload symbols used in the simulation process are data symbols in Table 2, with a payload length of 127 bytes for each data packet. The simulation channel is an additive white Gaussian noise channel.

[0151] Figure 9 shows the symbol error rate performance of SFD symbols and payload symbols on an additive white Gaussian noise channel. In Figure 9, the horizontal axis represents the power ratio (in dB) to the background noise of each chip, and the vertical axis represents the symbol error rate at the receiving end. From Figure 9, for the same symbol error rate, for example, a symbol error rate of 10 -3 When this is the case, the SFD symbol has a lower bit-to-background noise power ratio, which indicates that the demodulation performance of the SFD symbol is better than that of the payload symbol. In other words, in this embodiment of the present application, the demodulation performance of the SFD symbol or preamble symbol can be further improved. Also, physical layer setting #1 in Table 13 is indicated by the value of the SFD field being 11100101, which is compatible with existing protocols. In addition, the values ​​in the first set of values ​​in Table 13 do not include data symbol 0, thereby allowing the SFD field to maintain its original delimiter function. [Examples]

[0152] Embodiment 2 Embodiment 2 of the present invention primarily describes modifying the format of the PHR field and adding bits to the PHR field to indicate a different physical layer configuration.

[0153] Figure 10 is another schematic flowchart of a physical layer configuration instruction method according to one embodiment of the present invention. The first and second communication devices in this method may be any two devices capable of performing data transmission as shown in Figure 1 or Figure 2. As shown in Figure 10, the physical layer configuration instruction method includes, but is not limited to, the following steps.

[0154] S201: The first communication device generates a PPDU, which includes a PHR field, the length of the chip sequence corresponding to the PHR field is the target length, the PHR field includes instruction information, and the instruction information indicates the physical layer configuration.

[0155] S202: The first communication device transmits a signal, which is generated by the PPDU based on the physical layer configuration indicated by the instruction information.

[0156] In response, the second communication device receives the signal.

[0157] In some scenarios, the signal in the embodiments of the present invention may be a narrowband signal and may be used to support UWB in applications such as ranging, sensing, and data transmission. The signal may provide initial synchronization information for the UWB and the transmitted data. For example, control information, synchronization information, or data for the UWB may be carried within the signal payload. The application of the signal in step S202 in the UWB is not limited to the embodiments of the present invention.

[0158] Optionally, the structure of a PPDU may be shown in Figure 3. A PPDU includes, but is not limited to, a preamble field, an SFD field, a PHR field, and a payload field. Here, all bits of the preamble field may be 0, and the bit value of the SFD field may be fixed to 11100101.

[0159] Optionally, the length of the chip sequence corresponding to the PHR field in the PPDU may be the target length. The target length may be predefined, specified in a standard protocol, or determined by the first and second communication devices through negotiation. The method of determining the target length is not limited to the embodiments of this application, as long as the first and second communication devices can know the target length. For example, the target length may be 32 bits, 16 bits, 8 bits, or 4 bits.

[0160] It can be understood that when the length of the chip sequence corresponding to the PHR field is determined, the chip sequence corresponding to the PHR field is determined. That is, when modulation and spreading are performed on the PHR field, every 4 bits of the PHR field are mapped to one data symbol, and each data symbol is mapped to one chip sequence of target length. It can be further understood that the manner in which data symbols are mapped to chip sequences of different lengths may be specified in the standard protocol. For example, suppose the target length is 32 bits. A mapping table from data symbols to 32-bit chip sequences may be shown in Tables 2, 5, 8, or 11. Further details are again not described herein.

[0161] Optionally, the PHR field may contain instruction information, which may indicate the physical layer configuration. In a possible implementation, the physical layer configuration may include one or more of the following parameters: the length of the chip sequence corresponding to the payload field, the data rate, or whether the payload field has FEC coding. In other words, the instruction information may indicate the length of the chip sequence corresponding to the payload field, the data rate, or whether the payload field has FEC coding. The instruction information may be implemented by using multiple fields.

[0162] For example, Figure 11a illustrates yet another format of a PHR field according to one embodiment of the present invention. Figure 11a shows a possible format of a convolutional unsigned PHR field. As shown in Figure 11a, the length of the PHR field is 20 bits, where bits 0 and 1 (bits 0 and 1, total 2 bits) indicate the length of the chip sequence corresponding to the payload field, bits 2 and 3 (bits 2 and 3, total 2 bits) indicate the data rate, bit 4 (bit 4, total 1 bit) indicates whether the payload field has FEC coding, bits 5 through 11 (bits 5 through 11, total 7 bits) indicate the payload length (in bytes), and bits 12 through 19 (bits 12 through 19, total 8 bits) function as a header check sequence (HCS). Optionally, the PHR field shown in Figure 11a may alternatively be 12 bits and not include an HCS.

[0163] For example, FIG. 11b is a diagram of yet another format of the PHR field according to an embodiment of the present application. FIG. 11b shows a possible format of the PHR field having a convolutional code. As shown in FIG. 11b, the length of the PHR field is 26 bits. Bits 0 and 1 (bits 0 and 1, a total of 2 bits) indicate the length of the chip sequence corresponding to the payload field. Bits 2 and 3 (bits 2 and 3, a total of 2 bits) indicate the data rate. Bit 4 (bit 4, a total of 1 bit) indicates whether the payload field has an FEC code. Bits 5 to 11 (bits 5 to 11, a total of 7 bits) indicate the payload length (unit: byte). Bits 12 to 19 (bits 12 to 19, a total of 8 bits) function as the HCS. Bits 20 to 25 (bits 20 to 25, a total of 6 bits) are all 0 and function as padding. Optionally, the PHR field shown in FIG. 11b may alternatively be 18 bits and does not include the HCS. In this case, bits 12 to 17 are all 0 and function as padding.

[0164] In this embodiment of the present application, an HCS is added to the PHR field to check the bits in the PHR field. In this way, if there is an error bit in the PHR field, it cannot pass the HCS check, so it is fed back that the narrowband data transmitted this time needs to be retransmitted or discarded.

[0165] It can be understood that the correspondence between each bit in the PHR fields shown in FIGS. 11a and 11b and the meaning indicated by that bit is merely an example. For example, bits 0 and 1 may indicate the data rate, bit 2 may indicate whether the payload field has an FEC code, bits 3 and 4 may indicate the length of the chip sequence corresponding to the payload field, and the correspondence between the other bits and the meaning indicated by those other bits is the same as that in FIGS. 11a and 11b.

[0166] As shown in Table 1, it can be understood that there are four lengths of chip sequences corresponding to the payload field, namely 32 bits, 16 bits, 8 bits, and 4 bits, and three data rates, namely 250 kbps, 500 kbps, and 1000 kbps, respectively. Thus, the length of the chip sequence and the data rate corresponding to the payload field are indicated by 2 bits, respectively. Of course, the length of the chip sequence and the data rate corresponding to the payload field may be indicated in an alternative way. For example, if a bitmap is used for indication, the length of the chip sequence corresponding to the payload field needs to be indicated by 4 bits, and the data rate needs to be indicated by 3 bits. The specific indication forms of each parameter in Figures 11a and 11b are not limited to the embodiments of this application. It should be understood that as the possibilities for the length of the chip sequence corresponding to the payload field and data rate increase, the corresponding indication bits also increase. The number of indication bits for each parameter shown in Figures 11a and 11b are merely examples. In actual applications, the number of indicator bits for each parameter may be greater than or less than the number of indicator bits for each parameter shown in Figures 11a and 11b.

[0167] Furthermore, when there is no convolutional code, the length of the PHR field (in bits) is an integer multiple of 4, or when there is a convolutional code, the length of the PHR field (in bits) is an integer multiple of 2.

[0168] It can be further understood that the symbol lengths of the preamble field, SFD field, and PHR field in the physical layer configurations shown in Table 1 are determined by the bit lengths of the preamble field, SFD field, and PHR field in the PPDU (mapped to one data symbol every 4 bits), and that the bit lengths of the preamble field, SFD field, and PHR field in the PPDU are fixed. Therefore, when a physical layer configuration is indicated, the symbol lengths of the preamble field, SFD field, and PHR field do not need to be indicated. Also, the lengths of the chip sequences corresponding to the preamble field and SFD field in the physical layer configurations shown in Table 1 are all 32. Therefore, when a physical layer configuration is indicated, the lengths of the chip sequences corresponding to the preamble field and SFD field do not need to be indicated. Therefore, in this embodiment of the present application, all information relating to the physical layer configuration shown in Table 1 can be determined by indicating the length of the chip sequence corresponding to the payload field, the data rate, and whether the payload field has an FEC code.

[0169] In this embodiment of the present application, each physical layer parameter of the physical layer configuration (e.g., the length of the chip sequence corresponding to the payload field, the data rate, and whether the payload field has an FEC code) is indicated within the PHR field, thereby making the physical layer configuration more flexible and not limited to a few fixed physical layer configurations (e.g., the five physical layer configurations in Table 1).

[0170] In another possible implementation, the physical layer configuration may include one or more parameters such as the data rate, the length of the preamble field (which may be symbol length or bit length), the length of the SFD field (which may be symbol length or bit length), the length of the chip sequence corresponding to the preamble and SFD fields, the length of the PHR field (which may be symbol length or bit length), and the length of the chip sequence corresponding to the payload field, or forward error correction codes for the PHR and payload fields. For example, the indication information may indicate an index of the physical layer configuration, where one index identifies one physical layer configuration. For example, the five physical layer configurations shown in Table 1 are used as examples, and the indication information is 3 bits. For example, if the indicator value is 1 (decimal), it indicates a physical layer configuration with an index value of 1; if the indicator value is 2 (decimal), it indicates a physical layer configuration with an index value of 2; if the indicator value is 3 (decimal), it indicates a physical layer configuration with an index value of 3; if the indicator value is 4 (decimal), it indicates a physical layer configuration with an index value of 4; if the indicator value is 5 (decimal), it indicates a physical layer configuration with an index value of 5; or if the indicator value is 6 or 7 (decimal), it indicates a reserve. In this embodiment of the present application, the number of physical layer configurations is not limited, and the number of physical layer configurations may differ in different modulation schemes. The correspondence between physical layer configurations and index values ​​is not limited to the embodiment of the present application.

[0171] In this embodiment of the present application, the index of the physical layer configuration is indicated within the PHR field, thereby reducing overhead.

[0172] Since the length of the chip sequence corresponding to the PHR field is the target length, it can be understood that the physical layer configuration indicated by the instruction information herein may or may not include the length of the chip sequence corresponding to the PHR field, or it may, of course, include the length of the chip sequence corresponding to the PHR field. This is not limited to the embodiments of the present application.

[0173] Optionally, after generating the PPDU, the first communication device may generate the signal (where a modulated signal is obtained) based on the physical layer configuration and PPDU indicated by the instruction information in the PHR field, and transmit the signal. In other words, the signal is generated by the PPDU based on the physical layer configuration. For example, the first communication device may generate the signal according to the modulation and spreading process shown in Figure 6. Details are not described here. It can be understood that the modulation scheme in this embodiment of the present application may be O-QPSK modulation, or, of course, another modulation scheme, such as QPSK modulation. Specific modulation schemes are not limited to the embodiments of the present application.

[0174] S203: The second communication device demodulates the received signal and obtains the PHR field contained in the PPDU.

[0175] S204: The second communication device demodulates the received signal based on the physical layer configuration indicated by the instruction information in the PHR field to obtain the payload field contained in the PPDU.

[0176] Optionally, the second communication device determines a mapping table from data symbols to a chip sequence (i.e., the target length) based on the length of the chip sequence corresponding to the PHR field, and then performs processes such as demodulating the received signal (i.e., the reverse operation of modulation), mapping from chips to symbols, and mapping from symbols to bits based on the mapping table to obtain the PHR field included in the PPDU. For example, the second communication device may perform the reverse process of FIG. 6 to obtain the PHR field. In FIG. 6, O-QPSK modulation is used as an example, but in this embodiment of the present application, the modulation method is not limited to O-QPSK modulation, and alternatively, another modulation method, for example, QPSK modulation, may be used. Thereafter, the second communication device can demodulate the received signal based on the physical layer configuration indicated by the indication information in the PHR field and obtain the payload field (i.e., data information) included in the PPDU. For example, the second communication device may demodulate the received signal based on the length of the chip sequence corresponding to the payload field, the data rate, and whether the payload field has an FEC code to obtain the payload field.

[0177] In this embodiment of the present application, the length of the chip sequence corresponding to the PHR field is fixed, the format of the PHR field is modified, and the indication information is carried in the PHR field to indicate different physical layer configurations, so that the receiving end can obtain the PPDU through correct demodulation to obtain the payload (i.e., data) in the PPDU, thereby flexibly indicating different physical layer configurations.

[0178] The above content describes in detail the method provided in the present application. To facilitate the implementation of the foregoing solutions in the embodiments of the present application, the embodiments of the present application further provide corresponding devices or apparatuses.

[0179] In this application, the communication device is divided into functional modules based on embodiments of the method described above. For example, the communication device may be divided into functional modules corresponding to functions, or two or more functions may be integrated into a single processing module. The integrated module may be implemented in hardware form or in the form of a software functional module. Note that in this application, the module division is merely an example and represents a logical functional division. Other division methods may be used during actual implementation. The communication device in embodiments of this application will be described in detail below with reference to Figures 12 to 14.

[0180] Figure 12 shows the structure of a communication device according to one embodiment of the present invention. As shown in Figure 12, the communication device includes a transceiver unit 10 and a processing unit 20.

[0181] In some embodiments of the present application, the communication device may be the first communication device described above or a chip within the first communication device. Specifically, the communication device shown in Figure 12 may be configured to perform steps, functions, etc., performed by the first communication device in the method embodiments described above.

[0182] In one design, the processing unit 20 is configured to generate a PPDU, which includes a preamble field and an SFD field, where different values ​​in the SFD field correspond to different physical layer configurations, or different values ​​in the preamble field correspond to different physical layer configurations, and the transceiver unit 10 is configured to transmit a signal, which is generated by the PPDU based on the physical layer configuration corresponding to the value in the SFD field or the value in the preamble field.

[0183] For a detailed explanation of PPDU, preamble field, SFD field, physical layer configuration, etc., please refer to Method Embodiment 1 described above. Further details will not be explained again in this specification.

[0184] It should be understood that the specific description of the transceiver unit and processing unit shown in this embodiment of the present application is merely illustrative. For specific functions, steps, etc., of the transceiver unit and processing unit, please refer to the method embodiments described above. Details are again not described herein. For example, the transceiver unit 10 may be configured to perform step S102 shown in Figure 7, and the processing unit 20 may be configured to perform step S101 shown in Figure 7.

[0185] In an alternative design, the processing unit 20 is configured to generate a PPDU, which includes a PHR field, the length of the chip sequence corresponding to the PHR field being a target length, the PHR field containing instruction information, the instruction information indicating the physical layer configuration, and the transceiver unit 10 is configured to transmit a signal, which is generated by the PPDU based on the physical layer configuration indicated by the instruction information.

[0186] For a detailed description of the PPDU, PHR field, physical layer configuration, etc., please refer to the Method Embodiment 2 described above. Further details will not be described again in this specification.

[0187] It should be understood that the specific description of the transceiver unit and processing unit shown in this embodiment of the present application is merely illustrative. For specific functions, steps, etc., of the transceiver unit and processing unit, please refer to the embodiments of the method described above. Details are again not described herein. For example, the transceiver unit 10 may be configured to perform step S202 shown in Figure 9, and the processing unit 20 may be configured to perform step S201 shown in Figure 10.

[0188] Refer to Figure 12. In some other embodiments of the present application, the communication device may be the second communication device shown above or a chip within the second communication device. Specifically, the communication device shown in Figure 12 may be configured to perform steps, functions, etc., performed by the second communication device in the method embodiments described above.

[0189] In one design, the transceiver unit 10 is configured to receive a signal, which is generated by the PPDU based on a physical layer configuration corresponding to the value of the preamble field or the SFD field in the PPDU, and the processing unit 20 is configured to demodulate the signal to obtain the preamble field and SFD field contained in the PPDU, where different values ​​of the SFD field correspond to different physical layer configurations, or different values ​​of the preamble field correspond to different physical layer configurations, and the processing unit 20 is further configured to determine the physical layer configuration based on the value of the SFD field or the preamble field, and to demodulate the signal based on the determined physical layer configuration to obtain the payload field contained in the PPDU.

[0190] For a detailed explanation of PPDU, preamble field, SFD field, physical layer configuration, etc., please refer to Method Embodiment 1 described above. Further details will not be explained again in this specification.

[0191] It should be understood that the specific description of the transceiver unit and processing unit shown in this embodiment of the present application is merely illustrative. For specific functions, steps, etc., of the transceiver unit and processing unit, please refer to the method embodiments described above. Details are again not described herein. For example, the transceiver unit 10 may be configured to receive the signal transmitted in step S102 shown in Figure 7, and the processing unit 20 may be configured to perform steps S103 and S104 shown in Figure 7.

[0192] In an alternative design, the transceiver unit 10 is configured to receive a signal, which is generated by the PPDU based on a physical layer configuration indicated by directional information in the PHR field; the processing unit 20 is configured to demodulate the received signal to obtain the PHR field contained in the PPDU; and the processing unit 20 is further configured to demodulate the received signal based on a physical layer configuration indicated by directional information in the PHR field to obtain the payload field contained in the PPDU.

[0193] For a detailed description of the PPDU, PHR field, physical layer configuration, etc., please refer to the Method Embodiment 2 described above. Further details will not be described again in this specification.

[0194] It should be understood that the specific description of the transceiver unit and processing unit shown in this embodiment of the present application is merely illustrative. For specific functions, steps, etc., of the transceiver unit and processing unit, please refer to the method embodiments described above. Details are again not described herein. For example, the transceiver unit 10 may be configured to receive the signal transmitted in step S202 shown in Figure 10, and the processing unit 20 may be configured to perform steps S203 and S204 shown in Figure 10.

[0195] The above describes the communication device in the embodiment of the present application. The following describes possible product forms of the communication device. It should be understood that any form of product having the functionality of the communication device shown in Figure 12 falls within the scope of protection of the embodiment of the present application. Furthermore, it should be understood that the following description is merely an example and does not limit the product form of the communication device in the embodiment of the present application.

[0196] In one possible implementation, in the communication device shown in Figure 12, the processing unit 20 may be one or more processors, the transceiver unit 10 may be a transceiver, or the transceiver unit 10 may be a transmitting unit and a receiving unit. The transmitting unit may be a transmitter, and the receiving unit may be a receiver. The transmitting unit and the receiving unit are integrated into a single component, for example, a transceiver. In this embodiment of the present application, the processor and the transceiver may be coupled, and the manner of connection between the processor and the transceiver is not limited in this embodiment. In the process of performing the method described above, the process of transmitting information in the method described above (e.g., transmitting a signal) may be understood as the process of outputting the information described above by the processor. When outputting the information described above, the processor outputs the information described above to the transceiver, and the transceiver transmits the information. After the information described above is output by the processor, further processing may need to be performed on the information before the processed information arrives at the transceiver. Similarly, the process of receiving information in the method described above (e.g., receiving a signal) may be understood as the process of receiving the input information described above by the processor. When the processor receives input information, the transceiver receives the aforementioned information and inputs it to the processor. Furthermore, after the transceiver receives the aforementioned information, other processing may need to be performed on that information before the processed information is input to the processor.

[0197] Figure 13 is a diagram illustrating the structure of a communication device 1000 according to one embodiment of the present invention. The communication device 1000 may be a first communication device, a second communication device, or a chip within the first or second communication device. Figure 13 shows only the main components of the communication device 1000. In addition to the processor 1001 and transceiver 1002, the communication device may further include a memory 1003 and an input / output device (not shown).

[0198] The processor 1001 is configured primarily to process communication protocols and communication data, control the entire communication device, execute software programs, and process data from said software programs. The memory 1003 is configured primarily to store software programs and data. The transceiver 1002 may include a control circuit and an antenna. The control circuit is configured primarily to perform conversions between baseband signals and radio frequency signals and to process radio frequency signals. The antenna is configured primarily to receive / transmit radio frequency signals in the form of electromagnetic waves. Input / output devices, such as a touchscreen, display, or keyboard, are configured primarily to receive data entered by the user and output data to the user.

[0199] After the communication device is powered on, the processor 1001 may read the software program in the memory 1003, 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 1001 performs baseband processing on the data to be transmitted and outputs the baseband signal to the radio frequency circuit. The radio frequency circuit performs radio frequency processing on the baseband signal and then transmits the radio frequency signal to the outside through the antenna in the form of electromagnetic waves. When data is transmitted to the communication device, the radio frequency circuit receives the radio frequency signal through the antenna, converts the radio frequency signal into a baseband signal, and outputs the baseband signal to the processor 1001. The processor 1001 converts the baseband signal into data and processes the data.

[0200] In alternative implementations, radio frequency circuits and antennas may be located independently of the processor performing baseband processing. For example, in a distributed scenario, radio frequency circuits and antennas may be located remotely, independently of the communication equipment.

[0201] The processor 1001, transceiver 1002, and memory 1003 may be connected via a communication bus.

[0202] In one design, the communication device 1000 may be configured to perform the functions of the first communication device in Embodiment 1. The processor 1001 may be configured to perform step S101 in Figure 7 and / or another process of the technology described herein, and the transceiver 1002 may be configured to perform step S102 in Figure 7 and / or another process of the technology described herein.

[0203] In an alternative design, the communication device 1000 may be configured to perform the functions of the second communication device in Embodiment 1. The processor 1001 may be configured to perform steps S103 and S104 in Figure 7, and / or other processes of the technology described herein, and the transceiver 1002 may be configured to receive signals transmitted in step S102 in Figure 7, and / or other processes of the technology described herein.

[0204] In one design, the communication device 1000 may be configured to perform the functions of the first communication device in Embodiment 2. The processor 1001 may be configured to perform step S201 in Figure 10 and / or another process of the technology described herein, and the transceiver 1002 may be configured to perform step S202 in Figure 10 and / or another process of the technology described herein.

[0205] In an alternative design, the communication device 1000 may be configured to perform the functions of the second communication device in Embodiment 2. The processor 1001 may be configured to perform steps S203 and S204 in Figure 10, and / or other processes of the technology described herein, and the transceiver 1002 may be configured to receive signals transmitted in step S202 in Figure 10, and / or other processes of the technology described herein.

[0206] In any of the designs described above, the processor 1001 may include a transceiver configured to implement receiving and transmitting functions. For example, the transceiver may be a transceiver circuit, an interface, or an interface circuit. The transceiver circuit, interface, or interface circuit configured to implement receiving and transmitting functions may be separate or integrated together. The transceiver circuit, interface, or interface circuit may be configured to read and write code / data. Alternatively, the transceiver circuit, interface, or interface circuit may be configured to transmit or transfer signals.

[0207] In any of the aforementioned designs, the processor 1001 may store instructions. These instructions may be computer programs. The computer programs are executed on the processor 1001, thereby enabling the communication device 1000 to perform the methods described in the aforementioned method embodiments. The computer programs may be fixed to the processor 1001. In this case, the processor 1001 may be implemented by hardware.

[0208] In some implementations, the communication device 1000 may include a circuit that implements the transmit, receive, or communicate functions described in the method embodiments described above. The processors and transceivers described herein may be mounted on integrated circuits (ICs), analog ICs, radio frequency integrated circuits (RFICs), mixed-signal ICs, application-specific integrated circuits (ASICs), printed circuit boards (PCBs), electronic devices, and the like. Alternatively, the processors and transceivers may be manufactured using various IC technologies, such as complementary metal oxide semiconductors (CMOS), n-type metal oxide semiconductors (nMOS), positive channel metal oxide semiconductors (PMOS), bipolar junction transistors (BJTs), bipolar CMOS (BiCMOS), silicon germanium (SiGe), and gallium arsenide (GaAs).

[0209] The scope of communication devices described herein is not limited thereto, and the structure of communication devices is not limited to the structure shown in Figure 13. A communication device may be an independent device or part of a larger device. For example, a communication device may be the following: (1) Independent integrated circuits (ICs), chips, or chip systems or subsystems (2) A set comprising one or more ICs. Optionally, the set of ICs may further include a storage component configured to store data and computer programs. (3) ASIC, for example, a modem (4) A module that can be incorporated into other devices. (5) Receivers, terminals, smart terminals, mobile phones, wireless devices, handheld devices, mobile units, in-vehicle devices, network devices, cloud devices, artificial intelligence devices, etc. (6) Others.

[0210] In another possible implementation, in the communication device shown in Figure 12, the processing unit 20 may be one or more logic circuits, and the transceiver unit 10 may be an input / output interface, or may be called a communication interface, interface circuit, interface, etc. Alternatively, the transceiver unit 10 may be a transmit unit and a receive unit. The transmit unit may be an output interface, and the receive unit may be an input interface. The transmit unit and the receive unit are integrated into a single unit, for example, an input / output interface. Figure 14 is a diagram of another structure of a communication device according to one embodiment of the present application. As shown in Figure 14, the communication device shown in Figure 14 includes a logic circuit 901 and an interface 902. That is, the processing unit 20 may be implemented via the logic circuit 901, and the transceiver unit 10 may be implemented via the interface 902. The logic circuit 901 may be a chip, a processing circuit, an integrated circuit, a system on a chip (SoC), etc. The interface 902 may be a communication interface, an input / output interface, a pin, etc. For example, Figure 14 shows an example where the communication device is a chip, and the chip includes logic circuitry 901 and interface 902. It can be understood that the chip shown in this embodiment of the present application may include narrowband chips, ultra-wideband chips, and the like. This is not limited to the embodiments of the present application. Alternatively, the narrowband chip and the ultra-wideband chip may be integrated into a single device or chip, or they may be independent of each other. The implementation of the narrowband chip and the ultra-wideband chip in the device is not limited to the embodiments of the present application. The aforementioned steps of generating a PPDU and transmitting a signal may be performed by a narrowband chip.

[0211] In this embodiment of the present application, logic circuits and interfaces can be coupled to one another. The specific configuration of the connection between the logic circuits and interfaces is not limited to the embodiment of the present application.

[0212] For example, when a communication device is configured to perform a method, function, or step performed by the first communication device in Embodiment 1, the logic circuit 901 is configured to generate a PPDU, the PPDU including a preamble field and an SFD field, where different values ​​of the SFD field correspond to different physical layer configurations, or different values ​​of the preamble field correspond to different physical layer configurations, and the interface 902 is configured to output a signal, the signal being generated by the PPDU based on the physical layer configuration corresponding to the value of the SFD field or the value of the preamble field.

[0213] For example, when a communication device is configured to perform a method, function, or step performed by the second communication device in Embodiment 1, the interface 902 is configured to receive a signal, which is generated by the PPDU based on a physical layer configuration corresponding to the value of the preamble field or the SFD field in the PPDU, and the logic circuit 901 is configured to demodulate the signal to obtain the preamble field and SFD field contained in the PPDU, where different values ​​of the SFD field correspond to different physical layer configurations, or different values ​​of the preamble field correspond to different physical layer configurations, and the logic circuit 901 is further configured to determine the physical layer configuration based on the value of the SFD field or the preamble field, and to demodulate the signal based on the determined physical layer configuration to obtain the payload field contained in the PPDU.

[0214] For specific descriptions of PPDU, preamble field, SFD field, physical layer configuration, etc., it may be understood that you should refer to the method embodiments described above. Details are again not described herein.

[0215] For example, when a communication device is configured to perform a method, function, or step performed by the first communication device in Embodiment 2, the logic circuit 901 is configured to generate a PPDU, the PPDU includes a PHR field, the length of the chip sequence corresponding to the PHR field is a target length, the PHR field includes instruction information, the instruction information indicates a physical layer configuration, and the interface 902 is configured to output a signal, the signal generated by the PPDU based on the physical layer configuration indicated by the instruction information.

[0216] For example, when a communication device is configured to perform a method, function, or step performed by the second communication device in Embodiment 2, the interface 902 is configured to receive a signal, which is generated by the PPDU based on a physical layer configuration indicated by instruction information in the PHR field, the logic circuit 901 is configured to demodulate the received signal to obtain the PHR field contained in the PPDU, and the logic circuit 901 is further configured to demodulate the received signal based on a physical layer configuration indicated by instruction information in the PHR field to obtain the payload field contained in the PPDU.

[0217] For specific descriptions of PPDU, PHR field, physical layer configuration, etc., it may be understood that you should refer to the method embodiments described above. Details are again not described herein.

[0218] It can be understood that the communication device shown in the embodiments of the present application may implement the method provided in the embodiments of the present application in hardware form, or it may implement the method provided in the embodiments of the present application in software form. This is not limited to the embodiments of the present application.

[0219] For a specific implementation of the embodiment shown in Figure 14, please refer to the previously described embodiment. Further details will not be described again in this specification.

[0220] Certain embodiments of the present application further provide a wireless communication system. The wireless communication system includes a first communication device and a second communication device. The first communication device and the second communication device may be configured to execute the method of Embodiment 1 or Embodiment 2.

[0221] In addition, the present application further provides a computer program. The computer program is used to implement the operations and / or processes executed by the first communication device in the method provided in the present application.

[0222] The present application further provides a computer program. The computer program is used to implement the operations and / or processes executed by the second communication device in the method provided in the present application.

[0223] The present application further provides a computer-readable storage medium. The computer-readable storage medium stores computer code. When the computer code is executed on a computer, the computer is enabled to execute the operations and / or processes executed by the first communication device in the method provided in the present application.

[0224] The present application further provides a computer-readable storage medium. The computer-readable storage medium stores computer code. When the computer code is executed on a computer, the computer is enabled to execute the operations and / or processes executed by the second communication device in the method provided in the present application.

[0225] The present application further provides a computer program product. The computer program product includes computer code or a computer program. When the computer code or the computer program is executed on a computer, the operations and / or processes executed by the first communication device in the method provided in the present application are executed.

[0226] This application further provides a computer program product, which includes computer code or a computer program. When the computer code or computer program is executed on a computer, the operations and / or processes performed by the second communication device in the manner provided in this application are performed.

[0227] It should be understood that the systems, apparatus, and methods disclosed in some embodiments provided herein may be implemented in other ways. For example, the described apparatus embodiments are merely examples. For example, the division into units is merely a logical functional division and may be other divisions in actual implementation. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not performed. In addition, the mutual coupling, direct coupling, or communication connection shown or discussed may be implemented through some interfaces. Indirect coupling or communication connection between apparatus or units may be implemented electrically, mechanically, or in other ways.

[0228] Units described as separate parts may or may not be physically separate, and parts shown as units may or may not be physical units, may be located in one location, or may be distributed across multiple network units. Some or all of these units may be selected based on the actual requirements for implementing the technical effects of the solution provided in the embodiments of the present application.

[0229] In addition, the functional units in the embodiments of the present invention may be integrated into a single processing unit, each unit may exist physically independently, or two or more units may be integrated into a single unit. The integrated unit may be implemented in hardware form or in the form of a software functional unit.

[0230] When an integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, the integrated unit may be stored on a computer-readable storage medium. Based on such understanding, the technical solution of the present application, in essence, or in part, contributes to the prior art, or all or part of the technical solution may be implemented in the form of a software product. The computer software product is stored on a computer-readable storage medium and includes several instructions for instructing a computer device (which may be a personal computer, server, network device, etc.) to perform all or part of the steps of the method described in the embodiments of the present application. The aforementioned computer-readable storage medium includes any medium capable of storing program code, such as a USB flash drive, removable hard disk, read-only memory (ROM), random access memory (RAM), magnetic disk, or optical disk.

[0231] The foregoing description is merely a specific implementation of the present application and is not intended to limit the scope of protection of the present application. Any modifications or substitutions that are readily conceivable by a person skilled in the art within the scope of the art disclosed herein shall fall within the scope of protection of the present application. Accordingly, the scope of protection of the present application shall be subject to the scope of protection of the claims.

Claims

1. A method for specifying the physical layer configuration: A step in which a first communication device generates a physical layer protocol data unit (PPDU), wherein the PPDU includes a preamble field and an 8-bit frame start delimiter (SFD) field, wherein different values ​​of the SFD field correspond to different physical layer configurations, or different values ​​of the preamble field correspond to different physical layer configurations; The process includes the step of transmitting a signal by the first communication device, wherein the signal is generated by the PPDU based on a physical layer configuration corresponding to the value of the SFD field or the value of the preamble field, method.

2. The method according to claim 1, wherein the PPDU further includes a physical layer header (PHR) field and a payload field.

3. The method according to claim 2, wherein the physical layer configuration includes one or more of the following: a data rate, the length of the preamble field, the length of the chip sequence corresponding to the preamble field and the SFD field, the length of the PHR field, the length of the chip sequence corresponding to the PHR field and the payload field, or forward error correction codes for the PHR field and the payload field.

4. The physical layer configuration includes the length of the chip sequence corresponding to the PHR field and the payload field; The PHR field includes instruction information, which indicates whether the payload field has a forward error correction code. The method according to claim 2.

5. The value of the SFD field belongs to a first set of values, and the value of the preamble field is obtained by repeating a certain value in the first set of values ​​one or more times; The first set of values ​​contains M values, and these M values ​​meet the following conditions, namely: The sum of the Hamming distances between chip sequences corresponding to any two of the M values ​​is greater than or equal to the sum of the Hamming distances between chip sequences corresponding to any two of the M values ​​in the second set other than those in the first set. Satisfying the conditions, The aforementioned second set of values ​​contains N values, where N is greater than M, M is greater than 2, and both N and M are positive integers. The method according to claim 1.

6. The different values ​​of the SFD field Table 1 The method according to claim 1.

7. The method according to claim 1, wherein the value of the SFD field does not include any of the following values: a value in which the first four bits are 0000 and the last four bits are any value, a value in which the last four bits are 0000 and the first four bits are any value, and a value in which the eight bits are 00000000.

8. A method for specifying the physical layer configuration: A step in which a signal is received by a second communication device, the signal being generated by a physical layer protocol data unit (PPDU) based on a physical layer configuration corresponding to the value of the preamble field or the value of the 8-bit frame start delimiter (SFD) field in the PPDU; A step of demodulating the signal using the second communication device to obtain the preamble field and the SFD field included in the PPDU, wherein different values ​​of the SFD field correspond to different physical layer configurations, or different values ​​of the preamble field correspond to different physical layer configurations; The second communication device includes the steps of determining the physical layer configuration based on the value of the SFD field or the value of the preamble field, and demodulating the signal based on the determined physical layer configuration to obtain the payload field included in the PPDU, method.

9. The method according to claim 8, wherein the PPDU further includes a physical layer header (PHR) field and the payload field.

10. The method according to claim 9, wherein the physical layer configuration includes one or more of the following: a data rate, the length of the preamble field, the length of the chip sequence corresponding to the preamble field and the SFD field, the length of the PHR field, the length of the chip sequence corresponding to the PHR field and the payload field, or forward error correction codes for the PHR field and the payload field.

11. The physical layer configuration includes the length of the chip sequence corresponding to the PHR field and the payload field; The PHR field includes instruction information, which indicates whether the payload field has a forward error correction code. The method according to claim 9.

12. The value of the SFD field belongs to a first set of values, and the value of the preamble field is obtained by repeating a certain value in the first set of values ​​one or more times; The first set of values ​​contains M values, and these M values ​​meet the following conditions, namely: The sum of the Hamming distances between chip sequences corresponding to any two of the M values ​​is greater than or equal to the sum of the Hamming distances between chip sequences corresponding to any two of the M values ​​in the second set other than those in the first set. Satisfying the conditions, The aforementioned second set of values ​​contains N values, where N is greater than M, M is greater than 2, and both N and M are positive integers. The method according to claim 8.

13. The different values ​​of the SFD field Table 2 The method according to claim 8.

14. The method according to claim 8, wherein the value of the SFD field does not include any of the following values: a value in which the first four bits are 0000 and the last four bits are any value, a value in which the last four bits are 0000 and the first four bits are any value, and a value in which the eight bits are 00000000.

15. A processing unit configured to generate a Physical Layer Protocol Data Unit (PPDU), wherein the PPDU includes a preamble field and an 8-bit Frame Start Delimiter (SFD) field, wherein different values ​​of the SFD field correspond to different Physical Layer configurations, or different values ​​of the preamble field correspond to different Physical Layer configurations; A transceiver unit configured to transmit a signal, wherein the signal is generated by the PPDU based on a physical layer configuration corresponding to the value of the SFD field or the value of the preamble field. Communication device.

16. The apparatus according to claim 15, wherein the PPDU further comprises a physical layer header (PHR) field and a payload field.

17. The different values ​​of the SFD field Table 3 The apparatus according to claim 15.

18. A transceiver unit configured to receive a signal, wherein the signal is generated by a physical layer protocol data unit (PPDU) based on a physical layer configuration corresponding to the value of the preamble field or the value of the 8-bit frame start delimiter (SFD) field in the PPDU; A processing unit configured to demodulate the signal and obtain the preamble field and SFD field contained in the PPDU, wherein different values ​​of the SFD field correspond to different physical layer configurations, or different values ​​of the preamble field correspond to different physical layer configurations. The processing unit is further configured to determine the physical layer configuration based on the value of the SFD field or the value of the preamble field, and to demodulate the signal based on the determined physical layer configuration to obtain the payload field included in the PPDU. Communication device.

19. The communication device according to claim 18, wherein the PPDU further includes a physical layer header (PHR) field and the payload field.

20. The different values ​​of the SFD field Table 4 The apparatus according to claim 18.

21. A computer-readable storage medium, wherein the computer-readable storage medium is configured to store a computer program, and when the computer program is executed, the method according to any one of claims 1 to 14 is executed.

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