Modulation coding strategy indication method and corresponding device

Abstract

The embodiment of the invention discloses a modulation and coding strategy indication method and a corresponding device. The present application is applied to a wireless local area network system that supports one or more of an IEEE 802.11 ax next generation Wi-Fi protocol (e.g., 802.11 be, Wi-Fi 7 or EHT), an IEEE 802.11 be next generation Wi-Fi protocol (e.g., 802.11 bn, Wi-Fi 8, UHR), a Wi-Fi AI, a millimeter wave (mmWave), an ultra wide band (UWB), and a sensing. The method comprises: generating a physical layer protocol data unit (PPDU), the PPDU comprising a first field and a second field, the first field being used for indicating a first modulation and coding policy (MCS) combination, and the second field being used for indicating the number of spatial streams corresponding to one or more MCSs in the first MCS combination; the PPDU is sent; the bit overhead can be saved.

Description

Technical Field

[0001] The present application relates to the field of communications, and in particular to a modulation and coding strategy indication method and a corresponding device. Background Art

[0002] Wireless local area network (WLAN) started with 802.11a / b / g standards, and has gone through 802.11n standards, 802.11ac standards, 802.11ax standards, and the 802.11be standard that is still under discussion. Among them, the 802.11a / b / g standards only support single spatial streams and do not support multiple input multiple output (MIMO) transmission. The 802.11n standard supports MIMO of up to 4 space-time streams, and each space-time stream can use a different modulation and coding scheme (MCS) to adapt to the signal to noise ratio (SNR) of different space-time streams. This method is called unequal modulation (UEQM). Space-time streams take into account different spatial streams and space-time block coding (STBC) in the time dimension. When the transmitter does not use STBC, the space-time stream can also be called a spatial stream.

[0003] Nowadays, more and more terminals use 2 or even 4 antennas. Access points (APs) and non-AP STAs can use more antennas to perform MIMO communications with a larger number of spatial streams, and unbalanced modulation becomes more important. Compared with the 802.11n standard, the current standard considers more spatial streams and more modulation and coding strategies.

[0004] The method of simultaneously indicating the spatial stream and its corresponding MCS adopted by the 802.11n standard is suitable for the case where there are fewer spatial streams and fewer MCS types. When the maximum spatial stream may be 8 or more spatial streams, and the maximum modulation method may be 4096QAM or more, the signaling overhead of this method will increase exponentially. Therefore, it is necessary to study how to indicate the MCS corresponding to the spatial stream with fewer bits (overhead). Summary of the invention

[0005] The embodiment of the present application discloses a modulation and coding strategy indication method and a corresponding device, which can implement different MCSs for multiple spatial streams with fewer bits (overhead).

[0006] In a first aspect, an embodiment of the present application provides a modulation and coding strategy indication method, the method comprising: generating a physical layer protocol data unit (physical protocol data unit, PPDU), the PPDU comprising a first field and a second field, the first field is used to indicate a first modulation and coding strategy (modulation and coding scheme, MCS) combination, and the second field is used to indicate the number of spatial streams corresponding to one or more MCSs in the first MCS combination; sending the PPDU.

[0007] In an embodiment of the present application, the PPDU includes a first field and a second field, the first field is used to indicate a first MCS combination, and the second field is used to indicate the number of spatial streams corresponding to one or more MCSs in the first MCS combination; through the indication method of the first MCS combination, it is possible to achieve flexible indication of different MCSs for multiple spatial streams, and compared with indicating the MCSs used by each spatial stream under different numbers of spatial streams through one index, the signaling overhead is less.

[0008] In a second aspect, an embodiment of the present application provides another modulation and coding strategy indication method, the method comprising: receiving a PPDU, the PPDU comprising a first field and a second field, the first field being used to indicate a first MCS combination, and the second field being used to indicate the number of spatial streams corresponding to one or more MCSs in the first MCS combination; and obtaining the MCS corresponding to each spatial stream according to the PPDU. Exemplarily, according to the PPDU, obtaining the MCS corresponding to each spatial stream carrying the PPDU.

[0009] In an embodiment of the present application, the PPDU includes a first field and a second field, the first field is used to indicate a first MCS combination, and the second field is used to indicate the number of spatial streams corresponding to one or more MCSs in the first MCS combination; through the indication method of the first MCS combination, it is possible to achieve flexible indication of different MCSs for multiple spatial streams, and compared with indicating the MCSs used by each spatial stream under different numbers of spatial streams through one index, the signaling overhead is less.

[0010] In a possible implementation manner of the first aspect or the second aspect, the second field is used to indicate a spatial stream boundary corresponding to any MCS in the first MCS combination.

[0011] In this implementation, the second field is used to indicate the spatial stream boundary corresponding to any MCS in the first MCS combination, and the number of spatial streams corresponding to any MCS in the first MCS combination can be indicated by fewer bits.

[0012] In a possible implementation manner of the first aspect or the second aspect, the second field is further used to indicate the total number of spatial streams corresponding to the first MCS combination.

[0013] In this implementation, the second field is also used to indicate the total number of spatial streams corresponding to the first MCS combination. There is no need to use other fields to indicate the total number of spatial streams corresponding to the first MCS combination, which can save bit overhead.

[0014] In a possible implementation manner of the first aspect or the second aspect, the number of spatial streams corresponding to the same MCS indicated by the second field is less than or equal to a first threshold, and the first threshold is a positive integer less than 8.

[0015] If the number of spatial streams corresponding to the same MCS exceeds the first threshold, EQM may be used, or two MCSs may be used instead. Therefore, it is necessary to limit the number of spatial streams corresponding to the same MCS to be less than or equal to the first threshold.

[0016] In a possible implementation of the first aspect or the second aspect, when the value indicated by the second field is a first index, the second field is used to indicate the number of spatial streams corresponding to an MCS in the first MCS combination, and when the value indicated by the second field is a second index, the second field is used to indicate the number of spatial streams corresponding to multiple MCSs in the first MCS combination.

[0017] When the second field is used to indicate the number of spatial streams corresponding to an MCS in the first MCS combination, each spatial stream indicated by the second field adopts this MCS. That is, when the second field is used to indicate the number of spatial streams corresponding to an MCS in the first MCS combination, the second field also implicitly indicates equal modulation (EQM). When the second field is used to indicate the number of spatial streams corresponding to multiple MCSs in the first MCS combination, the second field is used to indicate that at least two spatial streams use different MCSs. That is, when the second field is used to indicate the number of spatial streams corresponding to multiple MCSs in the first MCS combination, the second field also implicitly indicates unequal modulation (UEQM). Unbalanced modulation can be called unequal modulation. It can be understood that the second field can implicitly indicate EQM or UEQM, and the PPDU does not have to carry a field indicating whether the user uses EQM or UEQN, which can save overhead.

[0018] In a possible implementation manner of the first aspect or the second aspect, the PPDU further includes a third field, where the third field is used to indicate whether a modulation mode of the PPDU is unbalanced modulation or balanced modulation.

[0019] In this implementation, the PPDU also includes a third field for indicating unbalanced modulation or balanced modulation, so that the receiving end parses the PPDU in a corresponding manner according to the third field.

[0020] In a possible implementation manner of the first aspect or the second aspect, the PPDU includes a first user field and a second user field, the first user field is associated with a first user, the second user field is associated with a second user, the first user field includes the first field and the second field, the second user field includes a fourth field and a fifth field, the fourth field is used to indicate the number of spatial streams of the second user, the fifth field is used to indicate the same MCS used by each spatial stream of the second user, and the length of the first user field is equal to the length of the second user field.

[0021] In this implementation, the PPDU includes a first user field and a second user field, and the length of the first user field is equal to the length of the second user field; the operation of parsing multiple user fields of equal length at the receiving end is simpler than the operation of parsing multiple user fields of unequal lengths, which can improve the efficiency of parsing the user field.

[0022] In a third aspect, an embodiment of the present application provides another modulation and coding strategy indication method, the method comprising: generating a PPDU, the PPDU comprising a sixth field and a seventh field, the sixth field being used to indicate the number of spatial streams of a third user, the seventh field being used to indicate the MCS used by each spatial stream of the third user, the MCS used by the spatial stream indicated by the seventh field being related to the number of spatial streams of the third user; and sending the PPDU.

[0023] In the embodiment of the present application, the seventh field is used to indicate the MCS respectively adopted by each spatial stream of the third user, and the MCS adopted by the spatial stream indicated by the seventh field is related to the number of spatial streams of the third user; compared with indicating the MCS respectively adopted by each spatial stream under different numbers of spatial streams through one index, the signaling overhead is less.

[0024] In a fourth aspect, an embodiment of the present application provides another modulation and coding strategy indication method, the method comprising: receiving a PPDU, the PPDU comprising a sixth field and a seventh field, the sixth field being used to indicate the number of spatial streams of a third user, the seventh field being used to indicate the MCS adopted by each spatial stream of the third user, the MCS adopted by the spatial stream indicated by the seventh field being related to the number of spatial streams of the third user; and obtaining the MCS adopted by the spatial stream of the third user according to the PPDU.

[0025] In the embodiment of the present application, the seventh field is used to indicate the MCS respectively adopted by each spatial stream of the third user, and the MCS adopted by the spatial stream indicated by the seventh field is related to the number of spatial streams of the third user; compared with indicating the MCS respectively adopted by each spatial stream under different numbers of spatial streams through one index, the signaling overhead is less.

[0026] In a possible implementation of the third aspect or the fourth aspect, the difference between the highest MCS order and the lowest MCS order adopted by the spatial stream indicated by the seventh field is less than or equal to a second threshold, and the second threshold is a positive integer less than 10.

[0027] When the difference between the highest MCS order and the lowest MCS order used by the spatial stream indicated by the seventh field is less than or equal to the second threshold, the throughput gain brought by the lowest MCS is not obvious. By limiting the difference between the highest MCS order and the lowest MCS order used by the spatial stream indicated by the seventh field to be less than or equal to the second threshold, the implementation complexity of the receiving end can be reduced.

[0028] In a possible implementation manner of the third aspect or the fourth aspect, the MCS used by the spatial stream indicated by the seventh field belongs to the MCS supported by the balanced modulation method.

[0029] In this implementation, the MCS used by the spatial stream indicated by the seventh field belongs to the MCS supported by the balanced modulation mode, which can reduce the implementation complexity of the transmitting end and the receiving end.

[0030] In a possible implementation manner of the third aspect or the fourth aspect, the seventh field is used to indicate that at least two spatial streams use different MCSs.

[0031] In this implementation, the MCS adopted by different spatial streams can be indicated by using fewer bits.

[0032] In a possible implementation manner of the third aspect or the fourth aspect, when the value indicated by the seventh field is a third index, the seventh field is used to indicate that the same MCS is used by each spatial stream of the third user, and when the value indicated by the seventh field is a fourth index, the seventh field is used to indicate that at least two spatial streams use different MCSs.

[0033] In this implementation, the seventh field may indicate UEQM or EQM, and the PPDU does not need to carry a field indicating whether the user adopts EQM or UEQN, which can save overhead.

[0034] In a possible implementation manner of the third aspect or the fourth aspect, the PPDU also includes an eighth field, and the eighth field is used to indicate unbalanced modulation or balanced modulation.

[0035] In this implementation, the PPDU further includes an eighth field for indicating unbalanced modulation or balanced modulation, so that the receiving end can parse the PPDU in a corresponding manner according to the third field.

[0036] In a possible implementation manner of the third aspect or the fourth aspect, the PPDU includes a third user field and a fourth user field, the third user field is associated with the third user, the fourth user field is associated with the fourth user, the seventh field included in the third user field is used to indicate that at least two spatial streams of the third user use different MCSs, the seventh field included in the fourth user field is used to indicate that the same MCS is used by each spatial stream of the fourth user, and the length of the third user field is equal to the length of the fourth user field.

[0037] In this implementation, the PPDU includes a third user field and a fourth user field, and the length of the third user field is equal to the length of the fourth user field; the operation of parsing multiple user fields of equal length at the receiving end is simpler than the operation of parsing multiple user fields of unequal lengths, which can improve the efficiency of parsing the user field.

[0038] In a fifth aspect, an embodiment of the present application provides another modulation and coding strategy indication method, the method comprising: generating a PPDU, the PPDU comprising a ninth field, the ninth field being used to indicate the number of spatial streams of a fifth user and the MCS adopted by each spatial stream of the fifth user; and sending the PPDU.

[0039] In the embodiment of the present application, the ninth field is used to indicate the number of spatial streams of the fifth user and the MCS respectively adopted by each spatial stream of the fifth user. There is no need to indicate the number of spatial streams of the fifth user through an additional field, which can save bit overhead.

[0040] In a sixth aspect, an embodiment of the present application provides another modulation and coding strategy indication method, the method comprising: receiving a PPDU, the PPDU comprising a ninth field, the ninth field being used to indicate the number of spatial streams of a fifth user and the MCS adopted by each spatial stream of the fifth user; according to the PPDU, obtaining the MCS adopted by the spatial stream of the fifth user.

[0041] In the embodiment of the present application, the ninth field is used to indicate the number of spatial streams of the fifth user and the MCS respectively adopted by each spatial stream of the fifth user. There is no need to indicate the number of spatial streams of the fifth user through an additional field, which can save bit overhead.

[0042] In a possible implementation manner of the fifth aspect or the sixth aspect, when the value indicated by the ninth field is the fifth index, the ninth field is used to indicate the number of spatial streams of the fifth user and the same MCS used by each spatial stream of the fifth user, and when the value indicated by the ninth field is the sixth index, the ninth field is used to indicate the number of spatial streams of the fifth user and the MCS used by each spatial stream of the fifth user, wherein the MCSs used by at least two spatial streams indicated by the ninth field are different.

[0043] In this implementation, the ninth field may indicate UEQM or EQM, and the PPDU does not need to carry a field indicating whether the user adopts EQM or UEQN, which can save overhead.

[0044] In a possible implementation manner of the fifth aspect or the sixth aspect, the PPDU includes a fifth user field and a sixth user field, the fifth user field is associated with the fifth user, the sixth user field is associated with the sixth user, the ninth field included in the fifth user field is used to indicate the number of spatial streams of the fifth user and the same MCS used by each spatial stream of the fifth user, the ninth field included in the sixth user field is used to indicate the number of spatial streams of the sixth user and the MCS used by each spatial stream of the sixth user, at least two spatial streams indicated by the ninth field included in the sixth user field have different MCSs, and the length of the fifth user field is equal to the length of the sixth user field.

[0045] In this implementation, the PPDU includes a fifth user field and a sixth user field, the length of the fifth user field is equal to the length of the sixth user field, and the operation of parsing multiple user fields of equal length at the receiving end is simpler than the operation of parsing multiple user fields of unequal lengths, which can improve the efficiency of parsing the user field.

[0046] In a seventh aspect, an embodiment of the present application provides a communication device, which has the function of implementing the behavior in the method embodiment of the first aspect above. The communication device may be a communication device, or a component of a communication device (such as a processor, a chip, or a chip system, etc.), or a logic module or software that can implement all or part of the functions of the communication device. The functions of the communication device may be implemented by hardware, or by hardware executing corresponding software, and the hardware or software includes one or more modules or units corresponding to the above functions. In one possible implementation, the communication device includes a transceiver module and a processing module, wherein: the processing module is used to generate a PPDU, the PPDU includes a first field and a second field, the first field is used to indicate a first MCS combination, and the second field is used to indicate the number of spatial streams corresponding to one or more MCSs in the first MCS combination; the transceiver module is used to send the PPDU.

[0047] In an embodiment of the present application, the PPDU includes a first field and a second field, the first field is used to indicate a first MCS combination, and the second field is used to indicate the number of spatial streams corresponding to one or more MCSs in the first MCS combination; through the indication method of the first MCS combination, it is possible to achieve flexible indication of different MCSs for multiple spatial streams, and compared with indicating the MCSs used by each spatial stream under different numbers of spatial streams through one index, the signaling overhead is less.

[0048] Possible implementations of the communication device of the seventh aspect may refer to various possible implementations of the first aspect.

[0049] For the technical effects brought about by various possible implementation methods of the seventh aspect, reference may be made to the introduction to the technical effects of the first aspect or various possible implementation methods of the first aspect.

[0050] In an eighth aspect, an embodiment of the present application provides a communication device, which has the function of implementing the behavior in the method embodiment of the second aspect above. The communication device may be a communication device, or a component of a communication device (such as a processor, a chip, or a chip system, etc.), or a logic module or software that can implement all or part of the functions of the communication device. The functions of the communication device may be implemented by hardware, or by hardware executing corresponding software, and the hardware or software includes one or more modules or units corresponding to the above functions. In a possible implementation, the communication device includes a transceiver module and a processing module, wherein: the transceiver module is used to receive a PPDU, the PPDU includes a first field and a second field, the first field is used to indicate a first MCS combination, and the second field is used to indicate the number of spatial streams corresponding to one or more MCSs in the first MCS combination; the processing module is used to obtain the MCS corresponding to each spatial stream according to the PPDU.

[0051] In an embodiment of the present application, the PPDU includes a first field and a second field, the first field is used to indicate a first MCS combination, and the second field is used to indicate the number of spatial streams corresponding to one or more MCSs in the first MCS combination; through the indication method of the first MCS combination, it is possible to achieve flexible indication of different MCSs for multiple spatial streams, and compared with indicating the MCSs used by each spatial stream under different numbers of spatial streams through one index, the signaling overhead is less.

[0052] Possible implementations of the communication device of the eighth aspect may refer to various possible implementations of the second aspect.

[0053] For the technical effects brought about by various possible implementation methods of the eighth aspect, reference may be made to the introduction to the technical effects of the second aspect or various possible implementation methods of the second aspect.

[0054] In the ninth aspect, an embodiment of the present application provides a communication device, which has the function of implementing the behavior in the method embodiment of the third aspect above. The communication device can be a communication device, or a component of a communication device (such as a processor, a chip, or a chip system, etc.), or a logic module or software that can implement all or part of the functions of the communication device. The function of the communication device can be implemented by hardware, or by hardware executing corresponding software implementations, and the hardware or software includes one or more modules or units corresponding to the above functions. In a possible implementation, the communication device includes a transceiver module and a processing module, wherein: the processing module is used to generate a PPDU, the PPDU includes a sixth field and a seventh field, the sixth field is used to indicate the number of spatial streams of the third user, the seventh field is used to indicate the MCS used by each spatial stream of the third user, and the MCS used by the spatial stream indicated by the seventh field is related to the number of spatial streams of the third user; the transceiver module is used to send the PPDU.

[0055] In the embodiment of the present application, the seventh field is used to indicate the MCS respectively adopted by each spatial stream of the third user, and the MCS adopted by the spatial stream indicated by the seventh field is related to the number of spatial streams of the third user; compared with indicating the MCS respectively adopted by each spatial stream under different numbers of spatial streams through one index, the signaling overhead is less.

[0056] Possible implementations of the communication device of the ninth aspect may refer to various possible implementations of the third aspect.

[0057] Regarding the technical effects brought about by various possible implementation methods of the ninth aspect, reference may be made to the introduction to the technical effects of the third aspect or various possible implementation methods of the third aspect.

[0058] In the tenth aspect, an embodiment of the present application provides a communication device, which has the function of implementing the behavior in the method embodiment of the fourth aspect above. The communication device can be a communication device, or a component of a communication device (such as a processor, a chip, or a chip system, etc.), or a logic module or software that can implement all or part of the functions of the communication device. The function of the communication device can be implemented by hardware, or can be implemented by hardware executing corresponding software, and the hardware or software includes one or more modules or units corresponding to the above functions. In a possible implementation, the communication device includes a transceiver module and a processing module, wherein: the transceiver module is used to receive a PPDU, and the PPDU includes a sixth field and a seventh field, the sixth field is used to indicate the number of spatial streams of the third user, and the seventh field is used to indicate the MCS used by each spatial stream of the third user, and the MCS used by the spatial stream indicated by the seventh field is related to the number of spatial streams of the third user; the processing module is used to obtain the MCS used by the spatial stream of the third user according to the PPDU.

[0059] Possible implementations of the communication device of the tenth aspect may refer to various possible implementations of the fourth aspect.

[0060] Regarding the technical effects brought about by various possible implementation methods of the tenth aspect, reference may be made to the introduction to the technical effects of the fourth aspect or various possible implementation methods of the fourth aspect.

[0061] In the eleventh aspect, an embodiment of the present application provides a communication device, which has the function of implementing the behavior in the method embodiment of the fifth aspect above. The communication device can be a communication device, or a component of a communication device (such as a processor, a chip, or a chip system, etc.), or a logic module or software that can implement all or part of the functions of the communication device. The functions of the communication device can be implemented by hardware, or by hardware executing corresponding software implementations, and the hardware or software includes one or more modules or units corresponding to the above functions. In one possible implementation, the communication device includes a transceiver module and a processing module, wherein: the processing module is used to generate a PPDU, and the PPDU includes a ninth field, and the ninth field is used to indicate the number of spatial streams of the fifth user and the MCS used by each spatial stream of the fifth user; the transceiver module is used to send the PPDU.

[0062] In the embodiment of the present application, the ninth field is used to indicate the number of spatial streams of the fifth user and the MCS respectively adopted by each spatial stream of the fifth user. There is no need to indicate the number of spatial streams of the fifth user through an additional field, which can save bit overhead.

[0063] Possible implementations of the communication device of the eleventh aspect may refer to various possible implementations of the fifth aspect.

[0064] Regarding the technical effects brought about by various possible implementation methods of the eleventh aspect, reference may be made to the introduction to the technical effects of the fifth aspect or various possible implementation methods of the fifth aspect.

[0065] In the twelfth aspect, an embodiment of the present application provides a communication device, which has the function of implementing the behavior in the above-mentioned sixth aspect method embodiment. The communication device can be a communication device, or a component of a communication device (such as a processor, a chip, or a chip system, etc.), or a logic module or software that can implement all or part of the functions of the communication device. The functions of the communication device can be implemented by hardware, or by hardware executing corresponding software implementations, and the hardware or software includes one or more modules or units corresponding to the above functions. In one possible implementation, the communication device includes a transceiver module and a processing module, wherein: the transceiver module is used to receive a PPDU, and the PPDU includes a ninth field, and the ninth field is used to indicate the number of spatial streams of the fifth user and the MCS respectively adopted by each spatial stream of the fifth user; the processing module is used to obtain the MCS adopted by the spatial stream of the fifth user according to the PPDU.

[0066] In the embodiment of the present application, the ninth field is used to indicate the number of spatial streams of the fifth user and the MCS respectively adopted by each spatial stream of the fifth user. There is no need to indicate the number of spatial streams of the fifth user through an additional field, which can save bit overhead.

[0067] Possible implementations of the communication device of the twelfth aspect may refer to various possible implementations of the sixth aspect.

[0068] Regarding the technical effects brought about by various possible implementation methods of the twelfth aspect, reference may be made to the introduction to the technical effects of the sixth aspect or various possible implementation methods of the sixth aspect.

[0069] In a thirteenth aspect, an embodiment of the present application provides another communication device, the communication device comprising a processor, the processor coupled to a memory, the memory storing computer program instructions, the processor being used to execute the computer program instructions, so that the communication device performs the method as shown in any one of the first aspect to the sixth aspect. Exemplarily, the communication device can be a chip, the processor is a processing unit in the chip, and the memory is a random access memory or cache in the chip.

[0070] In the embodiment of the present application, in the process of executing the above method, the process of sending information (or signal) in the above method can be understood as the process of outputting information based on the instructions of the processor. When outputting information, the processor outputs the information to the transceiver so that it can be transmitted by the transceiver. After the information is output by the processor, it may also need to be processed in other ways before it reaches the transceiver. Similarly, when the processor receives input information, the transceiver receives the information and inputs it into the processor. Furthermore, after the transceiver receives the information, the information may need to be processed in other ways before it is input into the processor.

[0071] For operations such as sending and / or receiving involved by the processor, unless otherwise specified or unless they conflict with the actual function or internal logic in the relevant description, they can be generally understood as instructions output based on the processor.

[0072] During the implementation process, the processor may be a processor specifically used to execute these methods, or may be a processor that executes computer instructions in a memory to execute these methods, such as a general-purpose processor, etc. For example, the processor may also be used to execute a program stored in the memory, and when the program is executed, the communication device executes the method as shown in the first aspect or any possible implementation of the first aspect.

[0073] In a possible implementation, the memory is located outside the communication device. In a possible implementation, the memory is located inside the communication device.

[0074] In a possible implementation, the processor and the memory may also be integrated into one device, that is, the processor and the memory may also be integrated together.

[0075] In a possible implementation, the communication device further includes a transceiver, and the transceiver is used to receive a signal or send a signal.

[0076] In the fourteenth aspect, an embodiment of the present application provides another communication device, which includes a processing circuit and an interface circuit, wherein the interface circuit is used to acquire data or output data; the processing circuit is used to execute the method shown in any one of the first to sixth aspects above.

[0077] In the fifteenth aspect, an embodiment of the present application provides a computer-readable storage medium, in which a computer program is stored. The computer program includes program instructions, and when the program instructions are executed, the computer executes the method shown in any one of the above-mentioned first aspect to the above-mentioned sixth aspect.

[0078] In the sixteenth aspect, an embodiment of the present application provides a computer program product, which includes a computer program, and the computer program includes program instructions, which, when executed, enable the computer to execute the method shown in any one of the above-mentioned first to sixth aspects.

[0079] In the seventeenth aspect, an embodiment of the present application provides a communication system, comprising the communication device described in the seventh aspect or any possible implementation of the seventh aspect, and the communication device described in the eighth aspect or any possible implementation of the eighth aspect.

[0080] In the eighteenth aspect, an embodiment of the present application provides a communication system, comprising the communication device described in the ninth aspect or any possible implementation of the ninth aspect, and the communication device described in the tenth aspect or any possible implementation of the tenth aspect.

[0081] In the nineteenth aspect, an embodiment of the present application provides a communication system, comprising the communication device described in the above-mentioned eleventh aspect or any possible implementation of the eleventh aspect, and the communication device described in the above-mentioned twelfth aspect or any possible implementation of the twelfth aspect.

[0082] In the twentieth aspect, an embodiment of the present application provides a chip, including a processor and a communication interface, wherein the processor reads instructions stored in a memory through the communication interface and executes a method as shown in any one of the first to sixth aspects above. BRIEF DESCRIPTION OF THE DRAWINGS

[0083] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the background technology, the drawings required for use in the embodiments of the present application or the background technology will be described below.

[0084] Figure 1 An example of a wireless communication system to which the technical solution provided in this application is applicable;

[0085] Figure 2 An interactive flow chart of a modulation and coding strategy indication method provided in an embodiment of the present application;

[0086] Figure 3 An example of the format of the user field in the PPDU provided in the embodiment of the present application;

[0087] Figure 4 An example of the format of the first SIG field in the PPDU provided in an embodiment of the present application;

[0088] Figure 5 Another example of the format of the first SIG field in the PPDU provided in an embodiment of the present application;

[0089] Figure 6 Another example of the format of the first SIG field in the PPDU provided in an embodiment of the present application;

[0090] Figure 7 An example of a PPDU format provided in an embodiment of the present application;

[0091] Figure 8 An example of another PPDU format provided in an embodiment of the present application;

[0092] Fig. 9 An example of a correspondence between an MCS and a spatial stream provided in an embodiment of the present application;

[0093] Fig.10 Another example of the correspondence between MCS and spatial stream provided in an embodiment of the present application;

[0094] Fig.11 Another example of the correspondence between MCS and spatial stream provided in an embodiment of the present application;

[0095] Fig.12 Another example of the format of the first SIG field in the PPDU provided in an embodiment of the present application;

[0096] Fig.13 Another example of the format of the first SIG field in the PPDU provided in an embodiment of the present application;

[0097] Fig.14 Another interactive flow chart of a modulation and coding strategy indication method provided in an embodiment of the present application;

[0098] Fig.15 An example of the format of the user field in the PPDU provided in the embodiment of the present application;

[0099] Fig.16 Another example of the format of the first SIG field in the PPDU provided in an embodiment of the present application;

[0100] Fig.17 Another example of the format of the first SIG field in the PPDU provided in an embodiment of the present application;

[0101] Fig.18 Another example of the format of the first SIG field in the PPDU provided in an embodiment of the present application;

[0102] Fig.19 Another example of the format of the first SIG field in the PPDU provided in an embodiment of the present application;

[0103] Fig. 20An example of the format of the user field in the PPDU provided in the embodiment of the present application;

[0104] Fig.21 A schematic diagram of the structure of a communication device 2100 provided in an embodiment of the present application;

[0105] Fig. 22 A schematic diagram of the structure of another communication device 220 provided in an embodiment of the present application;

[0106] Fig.23 A schematic diagram of the structure of another communication device 230 provided in an embodiment of the present application. DETAILED DESCRIPTION

[0107] The terms "first" and "second" in the specification, claims and drawings of this application are only used to distinguish different objects, rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units that are not listed, or may optionally include other steps or units that are inherent to these processes, methods, products or devices.

[0108] The "embodiment" mentioned in this article means that the specific features, structures or characteristics described in conjunction with the embodiment can be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It can be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0109] The terms used in the following embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to be used as limitations to the present application. As used in the specification and the appended claims of the present application, the singular expressions "one", "a kind of", "said", "above", "the" and "this" are intended to also include plural expressions, unless there is a clear contrary indication in the context. It should also be understood that the term "and / or" used in the present application refers to and includes any or all possible combinations of one or more listed items. For example, "A and / or B" can represent: only A exists, only B exists, and three situations of A and B exist at the same time, wherein A, B can be singular or plural. The term "multiple" used in the present application refers to two or more.

[0110] It can be understood that in each embodiment of the present application, "A corresponds to B" means that there is a corresponding relationship between A and B, and B can be determined according to A. However, it should also be understood that determining (or generating) B according to (or based on) A does not mean that B is determined (or generated) only according to (or based on) A, and B can also be determined (or generated) according to (or based on) A and / or other information.

[0111] As described in the background technology section, it is currently necessary to study how to implement multiple spatial streams using different MCSs using fewer bits (overhead). This application provides a technical solution for implementing multiple spatial streams using different MCSs using fewer bits. The following first introduces a communication system to which the technical solution provided by this application is applicable.

[0112] The technical solution of the present application is mainly applicable to wireless communication systems, which may comply with the wireless communication standards of the third generation partnership project (3GPP), or other wireless communication standards, such as the 802 series (e.g., 802.11, 802.15, or 802.20) of the Institute of Electrical and Electronics Engineers (IEEE). The technical solution of the present application can also be applied to wireless local area network systems such as the Internet of Things (IoT) network, ultra wideband (UWB) system, and vehicle to X (V2X) system. Of course, the technical solution of the present application can also be applied to other possible communication systems, such as long term evolution (LTE) system, LTE frequency division duplex (FDD) system, LTE time division duplex (TDD), universal mobile telecommunication system (UMTS), worldwide interoperability for microwave access (WiMAX) communication system, fifth generation (5G) communication system, and future sixth generation (6G) communication system, etc.

[0113] The embodiments of the present application are mainly described by deploying a WLAN system or a UWB system, especially a network using the IEEE 802.11 standard. It is easy for those skilled in the art to understand that the various aspects involved in the present application can be extended to other networks using various standards or protocols, for example, BLUETOOTH (Bluetooth), high performance radio LAN (HIPERLAN) (a wireless standard similar to the IEEE 802.11 standard, mainly used in Europe) and a wide area network (WAN), a personal area network (PAN) or other networks known now or developed later. Therefore, regardless of the coverage range and wireless access protocol used, the various aspects provided in the present application can be applied to any suitable wireless network.

[0114] The above-mentioned communication system applicable to the present application is only an example for illustration, and the communication system applicable to the present application is not limited to this. A unified description is given here and no further elaboration is given below.

[0115] The technical solution of the present application is applicable to data communication between an access point (AP) and one or more stations (STA), and is also applicable to communication between APs and between STAs. Figure 1 , Figure 1 An example of a wireless communication system to which the technical solution provided in the present application is applicable. The communication system includes one or more APs (only AP1 and AP2 are shown), and one or more STAs (only STA1, STA2, and STA3 are shown). Among them, both the access point and the STA support the WLAN protocol, and the WLAN protocol may include IEEE 802.11be (or Wi-Fi 7, EHT protocol), and may also include IEEE 802.15ab, IEEE802.11ax, IEEE 802.11ac and other protocols. Of course, with the continuous evolution and development of communication technology, the WLAN protocol may also include ultra high reliability (UHR) / IEEE802.11bn protocol, integrated millimeter wave (IMMW) protocol, IEEE802.11bn and subsequent generations of protocols. Taking WLAN as an example, the device for implementing the method of the present application may be an access point or STA in a WLAN, or a chip or processing system installed in an access point or STA.

[0116] An access point is a device with wireless communication function, supports communication using WLAN protocol, and has the function of communicating with other devices in the WLAN network (such as stations or other access points). Of course, it can also have the function of communicating with other devices. In a WLAN system, there are one or more access point type stations and one or more non-access point type stations (none access point station, non-AP STA). For ease of description, this article refers to access point type stations as access points (APs) and non-access point type stations as stations (STAs).

[0117] The access point can be a complete device, or a chip or processing system installed in the complete device. The device installed with these chips or processing systems can implement the methods and functions of the embodiments of the present application under the control of the chip or processing system (i.e., AP). The AP in the embodiments of the present application is a device that provides services for stations (STAs), and can support 802.11 series protocols, such as 802.15ab, 802.11ac, 802.11n, 802.11g, 802.11b and 802.11a, 802.11be, 802.11bn or their next generation. For example, the AP can be a communication entity such as a communication server, a router, a switch, a bridge, a computer, etc. AP may include macro base stations, micro base stations (also called small stations), pico base stations, femto base stations, relay stations, access points, gNBs, transmission reception points (TRPs), evolved Node Bs (eNBs), radio network controllers (RNCs), home base stations (e.g., homeevolved NodeBs, or home Node Bs, HNBs), base band units (BBUs), WiFi access points (APs), integrated access and backhaul (IABs), etc. Of course, APs may also be chips and processing systems in these various forms of devices, so as to implement the methods and functions of the embodiments of the present application.

[0118] A station is a device with wireless communication function, supports communication using WLAN protocol, and has the ability to communicate with other stations or access points in the WLAN network. For example, STA is any communication device that allows a user to communicate with an AP and then communicate with a WLAN. The communication device can be a complete device, or a chip or processing system installed in the complete device. Devices installed with these chips or processing systems can implement the methods and functions of the embodiments of the present application under the control of the chip or processing system (i.e., station). STA may include a mobile phone, a mobile station (MS), a tablet computer (pad), a computer with wireless transceiver function (such as a laptop), a virtual reality (VR) device, an augmented reality (AR) device, a wireless terminal in industrial control, a wireless terminal in self-driving, a wireless terminal in remote medical, a wireless terminal in smart grid, a wireless terminal in transportation safety, a wireless terminal in smart city, a wireless terminal in smart home, a subscriber unit, a cellular phone, a wireless data card, a personal digital assistant (PDA) computer, a tablet computer, a laptop computer, a machine type communication (MTC) terminal, etc. The station may include various handheld devices with wireless communication function, vehicle-mounted devices, wearable devices, computing devices or other processing devices connected to a wireless modem. Optionally, the station can be a handheld device (handset) with wireless communication function, a vehicle-mounted device, a wearable device or an Internet of Things, a terminal in the Internet of Vehicles, a terminal of any form in 5G and communication systems evolved after 5G, etc., and this application is not limited to this. The site can support 802.11 series protocols, such as 802.15ab, 802.11n, 802.11g, 802.11b, 802.11a, 802.11ac (Wi-Fi 5), 802.11ax (Wi-Fi 6), 802.11be (Wi-Fi 7), UHR / 802.11bn (Wi-Fi 8), IMW, or the next generation standard of Wi-Fi 8 or subsequent generations of standards and other WLAN standards.

[0119] The technical solution provided by the present application is applied to a scenario where a transmitter transmits a PPDU to a receiver, which scenario can be a downlink transmission scenario (for example, the transmitter is an AP and the receiver is a station), or an uplink transmission scenario (for example, the transmitter is a station and the receiver is an AP), or a scenario where a PPDU is transmitted between two APs, or a scenario where a PPDU is transmitted between two stations. The following introduces the scenario where a transmitter transmits a PPDU to a receiver, to which the technical solution provided by the present application is applied, by taking the downlink transmission scenario and the uplink transmission scenario as examples.

[0120] In the downlink transmission scenario, before sending PPDU to the receiving end (or user), the transmitting end (such as AP) allocates resource units (RU) to the receiving end. Each RU supports multiple spatial streams. These spatial streams can be used to transmit to one user (corresponding to non-MU-MIMO transmission mode) or to multiple users (corresponding to MU-MIMO transmission mode). Each spatial stream corresponds to an MCS. The transmitting end sends PPDU to the receiving end on each spatial stream supported by the RU allocated to the receiving end. The PPDU needs to indicate the MCS corresponding to each spatial stream supported by the RU. After receiving the PPDU, the receiving end obtains the MCS corresponding to each spatial stream and demodulates the data in the PPDU using the MCS corresponding to each spatial stream. In this scenario, the PPDU needs to indicate the MCS corresponding to each spatial stream supported by the RU.

[0121] In the uplink transmission scenario, before sending a PPDU to a receiving end (such as an AP), the transmitting end (such as a station) obtains the RU allocated to it by the receiving end. Each RU supports multiple spatial streams, which can be used to transmit to one user (corresponding to the non-MU-MIMO transmission mode) or to multiple users (corresponding to the MU-MIMO transmission mode). Each spatial stream corresponds to an MCS. The transmitting end sends a PPDU to the receiving end on the spatial streams supported by its allocated RU. The PPDU needs to indicate the MCS corresponding to each spatial stream supported by the RU. After receiving the PPDU, the receiving end obtains the MCS corresponding to each spatial stream of the transmitting end, and uses the MCS corresponding to each spatial stream of the transmitting end to demodulate the data in the PPDU. In this scenario, the PPDU also needs to indicate the MCS corresponding to each spatial stream supported by the RU.

[0122] From the above description, it can be seen that in the scenario where the transmitter transmits PPDU to the receiver, the PPDU needs to indicate the MCS corresponding to each spatial stream supported by the RU of the receiver. The present application provides a technical solution for indicating the MCS corresponding to the spatial stream by using fewer bits (overhead), which can be applied to the scenario where the transmitter transmits PPDU to the receiver, and can also be applied to other scenarios where the MCS corresponding to the spatial stream needs to be indicated.

[0123] The present application provides a method for indicating the MCS corresponding to a spatial stream: by carrying information indicating an MCS combination and indicating the number of spatial streams corresponding to one or more MCSs in the MCS combination in the PPDU, it is used to indicate the MCS used by the PPDU on different spatial streams. In the present application, an MCS combination includes multiple MCSs, an MCS is a combination of a QAM and a code rate, and in the MCS combination, the code rates of multiple MCSs are the same, that is, the code rates in multiple MCSs are the same. The MCS combination can be named as an MCS set or an MCS group, and the present application does not limit the naming of the MCS combination. In the present application, the MCS corresponds to the number of spatial streams, which is equivalent to the MCS corresponding to the number of spatial streams. In the present application, there are two understandings of the number of spatial streams corresponding to an MCS. One understanding is the sequence number (or identifier) ​​of the spatial stream corresponding to the MCS, such as the second spatial stream or spatial stream ②; the other understanding is the number of spatial streams corresponding to the MCS.

[0124] Based on the above ideas, in the technical solution provided by the present application, the PPDU includes a first field and a second field, the first field is used to carry information indicating the first MCS combination, and the second field is used to carry information indicating the number of spatial streams corresponding to one or more MCSs in the first MCS combination; the receiving end can obtain the MCS corresponding to each of its spatial streams based on these two fields. Exemplarily, the second field is used to carry information indicating the number of spatial streams corresponding to one or more MCSs in the MCS combination, which can be replaced by: The second field is used to carry information indicating the MCS corresponding to each of the spatial streams of the receiving end. Exemplarily, the second field is used to carry information indicating the number of spatial streams corresponding to one or more MCSs in the MCS combination, which can be replaced by: The second field is used to indicate the number of spatial streams corresponding to one or more MCSs in the MCS combination.

[0125] Below we first combine the attached Figure 2 Introduce the technical solution provided by this application. Figure 2 The following is an interactive flow chart of a modulation and coding strategy indication method provided in an embodiment of the present application. Figure 2 As shown, the method includes:

[0126] 201. The transmitting end generates a PPDU.

[0127] In the present application, a transmitting end (which may be referred to as a transmitting device) is one of an AP and a site, and a receiving end (which may be referred to as a receiving device) is the other of an AP and a site. For example, the transmitting end is an AP, and the receiving end is a site. For another example, the transmitting end is a site, and the receiving end is an AP. Alternatively, both the transmitting end and the receiving end are APs. Alternatively, both the transmitting end and the receiving end are sites. The number of transmitting ends may be one or more, and the embodiments of the present application do not limit this. The embodiments of the present application are described by taking a receiving end as an example.

[0128] The PPDU may include a first field and a second field. The first field is used to indicate a first MCS combination. The first field may be called an unequal modulation (UEQM) MCS combination indication field, i.e., a UEQM MCS combination indication field. The name of the field in the present application may be other different names, as long as the function of its substantial indication is the same, the naming of the field is not limited in the present application. The first MCS combination includes multiple MCSs. Exemplarily, the first MCS combination includes a combination of BPSK, QPSK, 16-QAM, and 64-QAM with the same code rate (e.g., 1 / 2 code rate). Exemplarily, the first MCS combination includes a combination of 64-QAM, 256-QAM, 1024-QAM, and 4096-QAM with the same code rate. Exemplarily, the first MCS combination may include a combination of 16,384QAM (referred to as 16K QAM) and a certain code rate, and may also include a combination of 65,536QAM (referred to as 64K QAM) and a certain code rate, and may also include a combination of a higher QAM and a code rate. The second field is used to indicate the number of spatial streams corresponding to one or more MCSs in the first MCS combination. The second field may be called an NSS combination indication field.

[0129] It is understandable that those skilled in the art know that the spatial stream is a virtual existence, so the number of spatial streams corresponding to an MCS can be understood in the following two ways, which can ultimately indicate the MCSs adopted by different spatial streams.

[0130] In a possible implementation, the second field is used to indicate the number of spatial streams corresponding to one or more MCSs in the above-mentioned first MCS combination, which can be: the second field is used to indicate the spatial streams corresponding to one or more MCSs in the first MCS combination. In other words, the second field is used to indicate the MCSs corresponding to the multiple spatial streams corresponding to the first MCS combination. In this implementation, the number of spatial streams can be understood as the sequence number of the spatial stream, for example, the second field is used to indicate that one MCS in the first MCS combination corresponds to the second spatial stream (or spatial stream ②). Exemplarily, the first MCS group includes the first MCS, the second MCS, the third MCS and the fourth MCS, and the second field is used to indicate that the first MCS corresponds to spatial stream ① and spatial stream ②, the second MCS corresponds to spatial stream ③ and spatial stream ④, the third MCS corresponds to spatial stream ⑤, and the fourth MCS corresponds to spatial stream ⑥, spatial stream ⑦ and spatial stream ⑧, wherein spatial stream ① to spatial stream ⑧ are spatial streams of any user. A certain MCS corresponding to one or more spatial streams can be understood as the one or more spatial streams using (or corresponding to) this MCS. For example, the first MCS corresponding to spatial stream ① and spatial stream ② can be understood as spatial stream ① and spatial stream ② first MCS. Exemplarily, the first MCS combination includes the first MCS, the second MCS, the third MCS and the fourth MCS, and the second field is used to indicate that the first MCS corresponds to spatial stream ① and spatial stream ②, the second MCS corresponds to spatial stream ③ and spatial stream ④, and the fourth MCS corresponds to spatial stream ⑤ and spatial stream ⑥, wherein spatial stream ① to spatial stream ⑥ are spatial streams of any user. Figures 9 to 11 Describes the manner in which the second field is used to indicate spatial streams corresponding to one or more MCSs in the first MCS combination.

[0131] In another possible implementation, the second field is used to indicate the number of spatial streams corresponding to one or more MCSs in the first MCS combination, which may be: The second field is used to indicate the number of spatial streams corresponding to one or more MCSs in the first MCS combination. It should be noted that the number of spatial streams refers to the total number of spatial streams, not the number of spatial streams. For example, an MCS corresponds to the first spatial stream and the second spatial stream, and the number of spatial streams corresponding to the MCS is 2. For another example, the number of spatial streams at the receiving end is 8, which means that the total number of spatial streams at the receiving end is 8, not the 8th spatial stream. Exemplarily, the first MCS combination includes a first MCS, a second MCS, a third MCS and a fourth MCS, and the second field is used to indicate that the first MCS corresponds to 2 spatial streams (that is, the number of spatial streams corresponding to the first MCS is 2), the second MCS corresponds to 2 spatial streams, the third MCS corresponds to 1 spatial stream (that is, the number of spatial streams corresponding to the third MCS is 1), and the fourth MCS corresponds to 3 spatial streams, wherein the total number of spatial streams corresponding to various MCSs in the first MCS combination (that is, the total number of spatial streams corresponding to the first MCS combination) is 8. Exemplarily, the first MCS combination includes a first MCS, a second MCS, a third MCS, and a fourth MCS, and the second field is used to indicate that the first MCS corresponds to 2 spatial streams (that is, the number of spatial streams corresponding to the first MCS is 2), the second MCS corresponds to 2 spatial streams, the third MCS corresponds to 0 spatial streams (that is, the number of spatial streams corresponding to the third MCS is 0), and the fourth MCS corresponds to 2 spatial streams, wherein the total number of spatial streams corresponding to the various MCSs in the first MCS combination is 6. Figures 9 to 11 Describes a manner in which the second field is used to indicate the number of spatial streams corresponding to one or more MCSs in the first MCS combination.

[0132] The above-mentioned PPDU may include one or more user fields, and at least one user field includes the above-mentioned first field and the above-mentioned second field. Exemplarily, a user field in the PPDU is associated with a user (e.g., a site), and the user field includes information that the user associated with the user field needs to read, and other users do not need to read the user field. For example, a user field in the PPDU is associated with user #1, and the user field includes the identifier of user #1. User #1 determines that the user field contains the information it needs to read based on the identifier of user #1 included in the user field. Other users (e.g., sites) ignore (disregard) the user field when the identifier included in the user field is not their own identifier.

[0133] The following describes a case where the PPDU includes one user field and a case where the PPDU includes multiple user fields.

[0134] In a possible implementation, the PPDU includes a user field, which includes a first field, a second field, and a third field (optional). The third field is used to indicate equal modulation (EQM) or UEQM. The third field can be called an EQM / UEQM indication field or an EQM / UEQM field. Figure 3 This is an example of the format of the user field in the PPDU provided in the embodiment of the present application. Figure 3 As shown, the user field in the PPDU includes: a STA identifier (identifier, ID), an EQM / UEQM field (ie, the third field), a UEQM MCS combination indication field (ie, the first field), an NSS combination indication field (ie, the second field mentioned above), a beamforming subfield (optional), and a coding subfield; wherein the STA identifier is an identifier of the STA (or user) associated with the user field, the beamforming subfield is used to indicate whether the data corresponding to the user adopts beamforming, and the coding subfield is used to indicate the coding type of the user. Figure 3 The user field shown is only an example of a user field in the PPDU. Figure 3 The user field shown may include more or fewer fields. For example, the user field in the PPDU includes a STA identifier (identifier, ID), a UEQMMCS combined indication field (i.e., the first field), an NSS combined indication field (i.e., the second field mentioned above), and a coding subfield. The embodiment of the present application does not limit the length and position of each field in the user field in the PPDU. For example, the length of the first field mentioned above may be 3 bits (bits), 4 bits, 5 bits, 6 bits, etc. For example, the length of the second field mentioned above may be 5 bits, 6 bits, 7 bits, 8 bits, 9 bits, etc. Exemplarily, in the user field of the PPDU, the length of the EQM / UEQM field is 1 bit (bit), the length of the UEQM MCS combined indication field is 4 bits, and the length of the NSS combined indication field is 6 bits. Exemplarily, in the user field of the PPDU, the length of the EQM / UEQM field is 1 bit (bit), the length of the UEQM MCS combined indication field is 4 bits, and the length of the NSS combined indication field is 5 bits. For example, when the value of the EQM / UEQM field is 0, the EQM / UEQM field is used to indicate EQM; when the value of the EQM / UEQM field is 1, the EQM / UEQM field is used to indicate UEQM.

[0135] In a possible implementation, the PPDU includes a first signaling (signal field, SIG) field, and the first SIG field includes the user field. The format of the PPDU is described below. A possible implementation is that the first SIG field is encoded and transmitted in units of 20MHz in the frequency domain. The concept of content channel (CC) is introduced here to characterize the content transmitted within a certain 20MHz in the first SIG field. Exemplarily, when the bandwidth of the PPDU is 20MHz, there is one CC in the first SIG field. Exemplarily, when the bandwidth of the PPDU is 40MHz, there are two CCs in the first SIG field, which are CC1 and CC2 from low to high in frequency. The format of the signaling field in the two content channels is the same, but the content may be different. Exemplarily, when the bandwidth of the PPDU is 80MHz, there are still 2 CCs, a total of 4 channels, so the overall resource unit allocation information is indicated on 4 channels according to the structure of CC1, CC2, CC1, CC2 from low to high in frequency. Exemplarily, when the bandwidth of the PPDU is 160 MHz or above, there are two content channels in each 80 MHz. The content of the first SIG field may be different in different 80 MHz. Exemplarily, the content in a content channel of the first SIG field is divided into a common field and a user-specific field, and the content of the common field in PPDUs of different formats may be different.

[0136] Figure 4 This is an example of the format of the first SIG field in the PPDU provided in the embodiment of the present application. Figure 4 As shown, the first SIG field includes a common field and a user-specific field. The user-specific field includes the above-mentioned user field, a cyclic redundancy check (CRC) field, a tail bit, and a padding bit (optional). The common field may include public information that cannot be carried in the universal signaling (U-SIG) field in the PPDU due to insufficient number of bits, that is, U-SIG overflow (such as spatial multiplexing parameters, protection intervals, and long training field sizes, etc.), and may also include a non-OFDMA user number field to indicate that the number of users transmitted is 1. The tail bit is used to end binary cyclic convolutional coding, and the padding bit may or may not exist. Figure 4 The format of the first SIG field shown is for single-user transmission, that is, the first SIG field includes one user field.

[0137] In a possible implementation, the transmitting end may send a PPDU (hereinafter referred to as PPDU#1) including the above-mentioned first field and the above-mentioned second field, for example, the user field of the PPDU#1 includes the first field and the second field, the user field of the PPDU#1 is associated with user#1, and the second field is used to indicate the number of spatial streams corresponding to one or more MCSs in the first MCS combination, and the number of spatial streams corresponding to one MCS in the first MCS combination is the number of spatial streams using the MCS in the spatial stream of user#1; and may also send a PPDU (hereinafter referred to as PPDU#2) including an MCS field (which may be referred to as an MCS indication field) and a number of spatial streams (number of spatialstreams, NSS), for example, the user field of the PPDU#2 includes an MCS field and an NSS, the user field of the PPDU#2 is associated with user#2, the NSS is the total number of spatial streams of user#2, and the MCS field is used to indicate that the same MCS is used by each spatial stream of user#2. That is, the transmitting end may send a PPDU including user fields of different formats, such as the above-mentioned PPDU#1 and the above-mentioned PPDU#2.

[0138] Exemplarily, when a user's spatial stream adopts UEQM, the user field in the PPDU sent by the transmitter includes the above-mentioned first field and the above-mentioned second field, so as to indicate the MCS adopted by each spatial stream of the user; when a user's spatial stream adopts EQM, the user field in the PPDU sent by the transmitter includes the above-mentioned MCS field and NSS, so as to indicate that the same MCS is adopted by each spatial stream of the user. Specifically, when a user's spatial stream adopts EQM, the user field in the PPDU sent by the transmitter includes the MCS field, NSS, a third field (i.e., an EQM / UEQM field) and a coding subfield, and the third field is used to indicate EQM.

[0139] In a possible implementation, the PPDU sent by the transmitting end includes a first SIG field, and the user field in the first SIG field includes an MCS field, an NSS, a third field (ie, an EQM / UEQM field), and a coding subfield. Figure 5 Another example of the format of the first SIG field in the PPDU provided in the embodiment of the present application. Figure 5 For a description of the fields in the first SIG field, see Figure 4 The description of the fields in the first SIG field is not repeated here. Figure 5 The format of the first SIG field shown (including one user field) is for single-user transmission. Figure 6 The format of the first SIG field shown (including multiple user fields) is for OFDMA transmission.

[0140] See also Figure 5There are two possible formats of the user field in the first SIG field of PPDU. One user field includes STA ID, EQM / UEQM field (ie, the third field), UEQM MCS combination indication field (ie, the first field), NSS combination indication field (ie, the second field mentioned above), beamforming subfield (optional), and coding subfield. The other user field includes STA ID, EQM / UEQM field, MCS field, NSS, reserved field (optional), beamforming subfield (optional), and coding subfield. Figure 5 The lengths of the user fields of the two formats shown may be equal or unequal. One possible approach is to reserve some bits (i.e., reserved fields) in the user field so that Figure 5 The lengths of the user fields of the two formats are equal, which can reduce the complexity of parsing the user fields at the receiving end. For example, the position and length of the reserved field in the user field can be flexibly configured as needed to make the lengths of the two user fields equal. Another possible way is to not reserve bits in the user field that are used to make the lengths of the user fields of the two formats equal (or aligned), which can save bit overhead. The following introduces some Figure 5 An example of the two formats of user fields being equal in length. Exemplarily, the sum of the length of the UEQM MCS combined indication field (i.e., the first field) and the length of the NSS combined indication field (i.e., the above-mentioned second field) is equal to the sum of the length of the MCS field, the length of the NSS, and the length of the reserved field (optional). Exemplarily, in one user field, the length of the UEQM MCS combined indication field is 4 bits, and the length of the NSS combined indication field is 6 bits; in another user field, the length of the MCS field is 4 bits, the length of the NSS is 2 bits, and the length of the reserved field is 4 bits. Exemplarily, in one user field, the length of the UEQM MCS combined indication field is 4 bits, and the length of the NSS combined indication field is 8 bits; in another user field, the length of the MCS field is 4 bits, the length of the NSS is 2 bits, and the length of the reserved field is 6 bits. In the present application, the position and length of each field in the user field are not limited. In addition, the user field in the present application may contain more than Figure 5 User fields may have more or fewer fields than shown.

[0141] In a possible implementation, the PPDU includes multiple user fields, p of the multiple user fields include the first field and the second field, q of the multiple user fields include a fourth field and a fifth field, the fourth field is used to indicate the number of spatial streams of a user (the user associated with the user field), and the fifth field is used to indicate that the spatial streams of the user use the same MCS, and the lengths of the user fields in the PPDU are equal or unequal. p is an integer greater than 0, and q is an integer greater than or equal to 0. That is, the PPDU may include user fields in two different formats. The following takes the PPDU including the first user field (including the first field and the second field) and the second user field (including the fourth field and the fifth field) as an example to introduce the PPDU including user fields in two different formats. For example, the PPDU includes a first user field and a second user field, the first user field is associated with the first user, the second user field is associated with the second user, the first user field includes the first field and the second field, the second user field includes a fourth field and a fifth field, the fourth field is used to indicate the number of spatial streams of the second user, the fifth field is used to indicate that the spatial streams of the second user use the same MCS, and the length of the first user field is equal to the length of the second user field. Exemplarily, the first user field includes: STA ID (i.e., the ID of the first user), EQM / UEQM field (i.e., the third field), UEQM MCS combination indication field (i.e., the first field), NSS combination indication field (i.e., the second field), beamforming subfield (optional), coding subfield, and the format of the first user field can be the same as Figure 5 The format of the user field corresponding to UEQM is the same as shown; the second user field includes: STA ID, EQM / UEQM field, MCS field, NSS, reserved field (optional), beamforming subfield (optional), coding subfield, and the format of the second user field can be the same as Figure 5 The format shown corresponds to the user field of the EQM.

[0142] There may be two formats of user fields in the PPDU, such as the first user field and the second user field. Any user field can indicate which user field it is through the EQM / UEQM field it contains, and the content of the subfields in the user fields of different formats will be different. The user fields of different formats in the PPDU are of equal length (that is, the lengths of the user fields of different formats are equal), which can simplify the complexity of decoding and parsing at the receiving end. Usually, the NSS combination indication field needs to indicate the number of spatial streams corresponding to one or more MCSs in the MCS combination, so the overhead will be relatively large. In order to make the first user field and the second user field of the same length or nearly the same length, one way is to minimize the overhead of the NSS combination indication field to achieve a trade-off between overhead and flexibility. Another way is to introduce some reserved bits (such as the reserved field in the first user field below) in the user field of EQM (that is, the second user field). The position and length of the reserved field (or reserved bit) in the second user field are not limited. The position and length of the reserved field (or reserved bit) in the second user field can be flexibly configured as needed. Exemplarily, the second user field includes multiple reserved fields, and the role of a part of the reserved fields in the second user field is to achieve alignment with the first user field, and the role of another part of the reserved fields in the second user field is not to achieve alignment with the first user field, but is introduced for other considerations. Exemplarily, before some reserved bits are introduced into the second user field, the second user field includes one or more reserved fields; after some reserved bits are introduced into the second user field, the length of the second user field is equal to the length of the first user field, and the first user field may include one or more reserved fields, or may not include a reserved field. Exemplarily, the sum of the length of the MCS field and the length of the NSS is S, the sum of the length of the UEQM MCS combination indication field and the length of the NSS combination indication field is T, the length of the reserved field in the second user field is greater than or equal to (TS), and the (TS) reserved bits in the second user field are used to align the length of the second user field with the length of the first user field, and S and T are both integers greater than 0, and S is less than T. Figure 5 A possible format of the second user field is shown, that is, the second user field includes a reserved field and the length of the reserved field is equal to (TS). Figure 5 The format of the second user field shown is only a possible example and should not be understood as limiting the second user field to include a reserved field. Figure 5In addition to the format of the second user field shown, the second user field may include multiple reserved fields. The present application does not limit the length and position of the multiple reserved fields, and no examples are given here one by one. For example, in the first user field, the length of the UEQM MCS combination indication field is 4 bits, and the length of the NSS combination indication field is 6 bits; in the second user field, the length of the MCS field is 4 bits, the length of the NSS is 3 bits, and the length of the reserved field is 3 bits. For another example, in the first user field, the length of the UEQMMCS combination indication field is 4 bits, and the length of the NSS combination indication field is 8 bits; in the second user field, the length of the MCS field is 4 bits, the length of the NSS is 4 bits, and the length of the reserved field is 4 bits. In the embodiment of the present application, EQM and UEQM can be implemented by user fields of different formats with equal lengths. The operation of parsing multiple user fields of equal lengths at the receiving end is simpler than the operation of parsing multiple user fields of unequal lengths, which can improve the efficiency of parsing user fields and reduce the complexity of implementation.

[0143] In a possible implementation manner, the first SIG field in the PPDU includes the first user field and the second user field, and the format of the first SIG field in the PPDU is for OFDMA transmission. Figure 6 Another example of the format of the first SIG field in the PPDU provided in the embodiment of the present application. Figure 6As shown, the first SIG field includes a common field and a user-specific field. The first coding block in the common field includes U-SIG overflow (for example, it contains some common information that cannot be carried in the U-SIG field due to insufficient number of bits), 1 or 2 resource unit allocation subfields (resource unit (RU) allocation subfield)-A, CRC and tail bits, and the second coding block in the common field includes 2 or 6 resource unit allocation subfields-B, CRC and tail bits; the user-specific field includes multiple user block fields, and a user block field includes one or 2 user fields, CRC and tail bits. When a user block field includes two user fields, the two user fields are carried in two content channels respectively. The resource unit allocation subfield in the first coding block can be called a resource unit allocation subfield-A, and the resource unit allocation subfield in the second coding block can be called a resource unit allocation subfield-B. The resource unit allocation subfield is used to allocate RU or MRU of the entire bandwidth, which is equivalent to dividing the entire bandwidth into several frequency domain sub-bandwidths. The resource unit allocation subfield is also used to indicate the number of users corresponding to each RU or multiple resource unit (MRU). The second coding block in the common field exists when the bandwidth of the PPDU is 160 MHz or 320 MHz. Figure 6 The first user field in may be an example of the second user field mentioned above. Figure 6 The second user field in can be an example of the first user field mentioned above. Figure 6 As shown, the first user field (i.e., the second user field) corresponds to EQM, and the first user field includes STA ID, EQM / UEQM field, MCS field, NSS, reserved field (optional), beamforming subfield (optional), and coding subfield; the second user field (i.e., the first user field) corresponds to UEQM, and the second user field includes STA ID (i.e., the ID of the first user), EQM / UEQM field (i.e., the third field), UEQM MCS combination indication field (i.e., the first field), NSS combination indication field (i.e., the above-mentioned second field), beamforming subfield (optional), and coding subfield. Exemplary, Figure 6 The lengths of the user fields in the PPDU shown are equal.

[0144] In a possible implementation, the PPDU includes multiple user fields, and the multiple user fields include the first field and the second field. For example, the first SIG field in the PPDU includes multiple user fields, and the format of one or more user fields is the same as the format of the first user field. The format of the first SIG field in the PPDU is for OFDMA transmission.

[0145] The embodiment of the present application does not limit the format of the PPDU. The above PPDU can be any PPDU that can include the above user field. Two examples of PPDU are introduced below.

[0146] For example, the PPDU is a UHR PPDU, which may also be called a UHR MU PPDU, where MU stands for multiple users. Figure 7 shown. Figure 7 This is an example of a PPDU format provided in an embodiment of the present application. Figure 7 As shown, the UHRPPDU includes: a legacy short training sequence (L-STF) field, a legacy long training sequence (L-LTF) field, a legacy signaling (legacy signal field A, L-SIG) field, a legacy signaling field repeated (repeated L-SIG, RL-SIG), a universal signaling (universal SIG, U-SIG) field, an ultra-high reliability signaling (ultra high reliability signalfield, UHR-SIG) field, an ultra-high reliability short training sequence (ultra high reliability short trainingfield, UHR-STF) field, an ultra-high reliability long training sequence (ultra high reliability long trainingfield, UHR-LTF) field, a data field, and a packet extension (packet extension, PE). Table 1 shows the meaning of each field in the UHR PPDU. The above-mentioned first SIG field can be any field in the UHRPPDU. Exemplarily, the above-mentioned first SIG field is the UHR-SIG field in the UHRPPDU. Exemplarily, the above-mentioned first SIG field is the U-SIG field in the UHRPPDU.

[0147] Table 1

[0148]

[0149] Exemplarily, the PPDU is an IMMW PPDU, which can support the IMMW standard. An example of the PPDU is Figure 8 shown. Figure 8 This is an example of another PPDU format provided in an embodiment of the present application. Figure 8As shown, the IMMWPPDU includes: a traditional short training sequence field, a traditional long training sequence field, a traditional signaling field, a traditional signaling field repetition, a general signaling field, an integrated millimeter wave signaling (IMMWsignal field, IMW-SIG) field, an integrated millimeter wave short training (IMMWshort training field, IMW-STF) field, an integrated millimeter wave length training (IMMWlong trainingfield, IMW-LTF) field, a data field, and a data packet extension (packet extension, PE). The above-mentioned first SIG field can be any field in the IMMWPPDU. Exemplarily, the above-mentioned first SIG field is the IMMW-SIG field in the IMMWPPDU. Exemplarily, the above-mentioned first SIG field is the U-SIG field in the IMMWPPDU. IMMWPPDU and UHRPPDU are only two examples of the above-mentioned PPDU. The above-mentioned PPDU can also be other types of PPDUs, which are not limited in the embodiments of the present application.

[0150] 202. The transmitter sends a PPDU.

[0151] Accordingly, the receiving end receives the PPDU. Exemplarily, when the PPDU is transmitted for a single user, one receiving end (i.e., the single user for which the PPDU is transmitted) receives the PPDU and parses the PPDU. Exemplarily, when the PPDU is transmitted for multiple users, multiple receiving ends (i.e., the users for which the PPDU is transmitted) receive the PPDU and parse the PPDU.

[0152] 203. The receiving end obtains the MCS corresponding to each spatial stream according to the PPDU.

[0153] In a possible implementation, the PPDU includes a user field, that is, the PPDU is transmitted for a single user, the user field is associated with the receiving end, and the user field includes a first field and a second field, the first field is used to indicate a first MCS combination, and the second field is used to indicate a spatial stream corresponding to one or more MCSs in the first MCS combination, and a spatial stream corresponding to an MCS in the first MCS combination is a spatial stream using the MCS at the receiving end; the receiving end obtains the MCS corresponding to each spatial stream according to the above PPDU, which can be: the receiving end obtains the MCS respectively used by each spatial stream of the receiving end according to the above PPDU. For example, the first MCS combination includes a first MCS, a second MCS, a third MCS, and a fourth MCS, and the receiving end obtains spatial streams ① and ② corresponding to the first MCS, spatial streams ③ and ④ corresponding to the second MCS, and spatial streams ⑤ and ⑥ corresponding to the fourth MCS according to the above PPDU, wherein spatial streams ① to ⑥ are spatial streams of the receiving end.

[0154] In a possible implementation, the PPDU includes a user field, that is, the PPDU is transmitted for a single user, the user field is associated with the receiving end, and the user field includes a first field and a second field, the first field is used to indicate a first MCS combination, and the second field is used to indicate the number of spatial streams corresponding to one or more MCSs in the first MCS combination, and the number of spatial streams corresponding to one MCS in the first MCS combination is the number of spatial streams using this MCS in the spatial streams of the receiving end; the receiving end obtains the MCS corresponding to each spatial stream according to the above PPDU, which can be: the receiving end obtains the number of spatial streams using various MCSs in the spatial streams of the receiving end according to the above PPDU. For example, the first MCS combination includes a first MCS, a second MCS, a third MCS, and a fourth MCS, and the receiving end obtains, according to the above PPDU, that 2 spatial streams use the first MCS, 2 spatial streams use the second MCS, 1 spatial stream uses the third MCS, and 3 spatial streams use the fourth MCS. For another example, the first MCS combination includes a first MCS, a second MCS, a third MCS and a fourth MCS. The receiving end obtains, based on the above PPDU, that 2 spatial streams use the first MCS, 2 spatial streams use the second MCS, 0 spatial streams use the third MCS, and 2 spatial streams use the fourth MCS.

[0155] In a possible implementation, the PPDU includes the first user field and the second user field, that is, the PPDU is for multi-user transmission, the first user field is associated with the first user (receiving end #1), the second user field is associated with the second user (receiving end #2), the first user field includes the first field and the second field, the second user field includes the fourth field and the fifth field, the fourth field is used to indicate the number of spatial streams of the second user, and the fifth field is used to indicate that the same MCS is used for each spatial stream of the second user. Exemplarily, the receiving end #1 reads the content of the first user field in the PPDU and ignores the content of the second user field in the PPDU, and the receiving end #2 reads the content of the second user field in the PPDU and ignores the content of the first user field in the PPDU. An example of step 203 is: the receiving end #1 obtains the MCS used by each spatial stream of the receiving end #1 according to the above PPDU. Another example of step 203 is: the receiving end #1 obtains the number of spatial streams using various MCSs in the spatial stream of the receiving end #1 according to the above PPDU. Another example of step 203 is: the receiving end #2 obtains the same MCS used by each spatial stream of the receiving end #2 according to the PPDU.

[0156] In a possible implementation, after obtaining the MCS used by each spatial stream of the first user, the receiving end demodulates the data according to the MCS used by each spatial stream of the first user. For example, the receiving end demodulates the data field in the PPDU according to the MCS used by each spatial stream of the first user.

[0157] In an embodiment of the present application, the PPDU includes a first field and a second field, the first field is used to indicate a first MCS combination, and the second field is used to indicate the number of spatial streams corresponding to one or more MCSs in the first MCS combination; through the indication method of the first MCS combination, it is possible to achieve flexible indication of different MCSs for multiple spatial streams, and compared with indicating the MCSs used by each spatial stream under different numbers of spatial streams through one index, the signaling overhead is less.

[0158] The following describes the manner in which the first field indicates the first MCS combination in conjunction with Table 2 and Table 4.

[0159] In a possible implementation, the value of the first field is an index, and the index indicates an MCS combination, namely, the first MCS combination. The index represented by the value of the first field may be any index in the basic MCS indication table, and one index defined in the basic MCS indication table indicates an MCS combination. The basic MCS indication table may be referred to as an MCS combination indication table, or may be referred to as other tables, which is not limited in this application. An index in the basic MCS indication table indicates a set of QAM combinations at a certain code rate, namely, an MCS combination. Table 2 is an example of a basic MCS indication table.

[0160] Table 2

[0161]

[0162]

[0163] Referring to Table 2, when the value of the first field is index 0, the first MCS combination is a combination of the first QAM combination and a 1 / 2 code rate, and the first QAM combination includes BPSK, QPSK, 16-QAM, and 64-QAM; when the value of the first field is index 1, the first MCS combination is a combination of the second QAM combination and a 1 / 2 code rate, and the second QAM combination includes QPSK, 16-QAM, 64-QAM, and 256-QAM; when the value of the first field is index 2, the first MCS combination is a combination of the second QAM combination and a 3 / 4 code rate, and the second QAM combination includes QPSK, 16-QAM, 64-QAM, and 256-QAM; and so on. It should be noted that Table 2 is an example of a basic MCS indication table. Compared with Table 2, the basic MCS indication table may include more or fewer correspondences between indexes and MCS combinations. In addition, the correspondence between the indexes and MCS combinations in Table 2 is not limited. That is to say, the table obtained by adding, deleting, deforming, or modifying the correspondence between the index and the MCS combination on the basis of Table 2 belongs to the basic MCS indication table protected by this application.

[0164] In a possible implementation, the meaning of the index in the basic MCS indication table may correspond to the meaning of the index in the MCS indication table under EQM modulation. Table 3 is an example of an MCS indication table under EQM modulation.

[0165] Table 3

[0166]

[0167] Table 4 is another example of the basic MCS indication table.

[0168] Table 4

[0169]

[0170]

[0171] Referring to Table 4, the meaning of the index in the basic MCS indication table corresponds to the meaning of the index in the MCS indication table under the same EQM modulation. In other words, Table 4 shows the meaning of the index under EQM and the meaning under UEQM. Table 4 can be obtained by combining Table 2 and Table 3. For example, index 0 indicates a combination of BPSK and 1 / 2 and a first MCS combination, the first MCS combination is a combination of a first QAM combination and a 1 / 2 code rate, and the first QAM combination includes BPSK, QPSK, 16-QAM, and 64-QAM. Table 4 can be used as both an MCS indication table under EQM modulation and a basic MCS indication table. The receiving end can know whether the index in Table 4 indicates an MCS (meaning under EQM) or an MCS combination (meaning under UEQM) in combination with the EQM / UEQM field. For example, when the value of the EQM / UEQM field is 0, the receiving end knows that the index in Table 4 indicates an MCS; when the value of the EQM / UEQM field is 1, the receiving end knows that the index in Table 4 indicates an MCS combination. Exemplarily, when the EQM / UEQM field in the user field indicates EQM, if the value of a field in the user field (such as the MCS field) is index 0, the field indicates a combination of BPSK and 1 / 2; when the EQM / UEQM field in the user field indicates UEQM, if the value of a field in the user field (such as the UEQM MCS combination indication field) is index 0, the field indicates a first MCS combination, and the first MCS combination is a combination of a first QAM combination and a 1 / 2 code rate. It should be noted that Table 4 is an example of a basic MCS indication table. Compared with Table 4, the basic MCS indication table may include more or fewer correspondences between indexes and MCS combinations. In addition, the correspondence between the index and the MCS combination in Table 4 is not limited. That is to say, the table obtained by adding, deleting, deforming, or modifying the correspondence between the index and the MCS combination on the basis of Table 4 belongs to the basic MCS indication table protected by this application.

[0172] The above describes the manner in which the first field indicates the first MCS combination. The following describes the possible manner in which the second field indicates the number of spatial streams corresponding to one or more MCSs in the first MCS combination.

[0173] In a possible implementation, the second field is used to indicate the spatial streams corresponding to one or more MCSs in the first MCS combination. In other words, the second field is used to indicate which spatial streams of a user (e.g., a receiving end) correspond to which MCS in the first MCS combination. In a possible implementation, the second field is used to indicate the spatial stream boundary corresponding to any MCS in the first MCS combination. In other words, the second field is used to indicate the spatial stream boundary of any MCS in the first MCS combination. The spatial stream boundary corresponding to an MCS may indicate the maximum sequence number (or maximum index) of the spatial stream using the MCS. The spatial stream corresponding to an MCS may be a spatial stream between the spatial stream boundary corresponding to the MCS (including the spatial stream corresponding to the sequence number indicated by the spatial stream boundary corresponding to the MCS) and the spatial stream boundary corresponding to the previous MCS of the MCS (excluding the spatial stream corresponding to the sequence number indicated by the spatial stream boundary corresponding to the previous MCS). Exemplarily, the sequence numbers of the multiple spatial streams corresponding to the first MCS combination are ①, ②, ③, ..., respectively. The spatial streams whose sequence numbers are less than or equal to the sequence numbers represented by the spatial stream boundary corresponding to the first MCS adopt the first MCS; the spatial streams whose sequence numbers are greater than the spatial stream boundary corresponding to the first MCS and less than or equal to the sequence numbers represented by the spatial stream boundary corresponding to the second MCS adopt the second MCS; the spatial streams whose sequence numbers are greater than the spatial stream boundary corresponding to the second MCS and less than or equal to the sequence numbers represented by the spatial stream boundary corresponding to the third MCS adopt the third MCS; and so on. The embodiment of the present application does not limit the number of spatial streams corresponding to the first MCS combination.

[0174] Exemplarily, if the first MCS combination includes a first MCS, a second MCS, a third MCS, and a fourth MCS, the second field is used to indicate a spatial stream boundary corresponding to the first MCS, a spatial stream boundary corresponding to the second MCS, a spatial stream boundary corresponding to the third MCS, and a spatial stream boundary corresponding to the fourth MCS. For example, the value of the second field represents index 175 in Table 5 below, and the four spatial stream boundaries indicated by the index 175 are represented by 2 4 5 8, where 2 represents the spatial stream boundary corresponding to the first MCS (i.e., the maximum sequence number of the spatial stream using the first MCS is ②), 4 represents the spatial stream boundary corresponding to the second MCS, 5 represents the spatial stream boundary corresponding to the third MCS, and 8 represents the spatial stream boundary corresponding to the fourth MCS. The four spatial stream boundaries represent that the first MCS corresponds to spatial stream ① and spatial stream ②, the second MCS corresponds to spatial stream ③ and spatial stream ④, the third MCS corresponds to spatial stream ⑤, and the fourth MCS corresponds to spatial stream ⑥, spatial stream ⑦, and spatial stream ⑧. For ease of understanding, the four spatial stream boundaries indicated by the second field can be understood as the positions of the four boards that divide the multiple spatial streams corresponding to the first MCS combination. The four boards correspond to four MCSs. The spatial streams with serial numbers less than or equal to the first board use the first MCS, the spatial streams with serial numbers greater than the first board and less than or equal to the second board use the second MCS, the spatial streams with serial numbers greater than the second board and less than or equal to the third board use the third MCS, and the spatial streams with serial numbers greater than the third board and less than or equal to the fourth board use the fourth MCS. The serial numbers of the multiple spatial streams corresponding to the first MCS combination are ①, ②, ③, ..., respectively, and the number of spatial streams corresponding to the first MCS combination is not limited.

[0175] In a possible implementation, the second field is also used to indicate the total number of spatial streams corresponding to the first MCS combination. Exemplarily, the first MCS combination includes g MCSs, and the value of the second field represents an index (e.g., the index in Table 5), and the g spatial stream boundaries indicated by the index are represented by G1G2...Gg (e.g., 2 4 5 8), and Gg is the total number of spatial streams corresponding to the first MCS combination. g is an integer greater than 0. G1 represents the spatial stream boundary corresponding to the first MCS, G2 represents the spatial stream boundary corresponding to the first MCS, ..., Gg represents the spatial stream boundary corresponding to the g-th MCS. G1, G2, ..., Gg are all integers greater than 0, and G is an integer greater than 1. For example, the first MCS combination includes 4 MCSs, and the value of the second field represents an index, and the spatial stream boundary corresponding to the fourth MCS indicated by the index is represented by H. The second field is also used to indicate that the total number of spatial streams corresponding to the first MCS combination is H, and H is an integer greater than 0.

[0176] Fig. 9An example of the correspondence between an MCS and a spatial stream provided in an embodiment of the present application. Exemplarily, the value of the second field represents index 175 in Table 5 below, and the four spatial stream boundaries indicated by index 175 are represented by 2 4 5 8, Fig. 9 The positions of the four panels in the first MCS combination represent the four spatial stream boundaries indicated by the second field. The four spatial stream boundaries indicated by the second field are used to indicate the spatial streams corresponding to one or more MCSs in the first MCS combination. Fig. 9 As shown, the first board = 2, the second board = 4, the third board = 5, the fourth board = 8, the first MCS corresponds to spatial stream ① and spatial stream ② (i.e., spatial stream ① and spatial stream ② use the first MCS), the second MCS corresponds to spatial stream ③ and spatial stream ④, the third MCS corresponds to spatial stream ⑤, and the fourth MCS corresponds to spatial stream ⑥, spatial stream ⑦, and spatial stream ⑧. For example, the spatial stream boundary corresponding to the fourth MCS indicated by the second field is represented by H, and the second field is also used to indicate that the total number of spatial streams corresponding to the first MCS combination is H, and H is an integer greater than 0. See Fig. 9 , the total number of spatial streams corresponding to the first MCS combination can be obtained by the position of the fourth board (the last board), that is, the total number of spatial streams is 8.

[0177] Among the boards that divide the multiple spatial streams corresponding to the first MCS combination, the positions of more than one board can overlap. If two boards overlap, it means that no spatial stream uses the MCS corresponding to the middle of the two boards. Fig.10 Another example of the correspondence between MCS and spatial stream provided in the embodiment of the present application. Exemplarily, the value of the second field represents index 169 in Table 5 below (for example, the value of the second field is 169), and the four spatial stream boundaries indicated by index 169 in Table 5 are represented by 2446. Fig.10 The positions of the four panels in the second field indicate the four spatial stream boundaries. Fig.10 As shown, the first board = 2, the second board = 4, the third board = 4, the fourth board = 6, the first MCS corresponds to spatial stream ① and spatial stream ② (that is, spatial stream ① and spatial stream ② use the first MCS), the second MCS corresponds to spatial stream ③ and spatial stream ④, the fourth MCS corresponds to spatial stream ⑤ and spatial stream ⑥, and the total number of spatial streams is 6. Fig.10 , the total number of spatial streams corresponding to the first MCS combination can be obtained by the position of the fourth board, that is, the total number of spatial streams is 6.

[0178] Fig.11 Another example of the correspondence between MCS and spatial streams provided in the embodiment of the present application. Exemplarily, the value of the second field represents index 35 in Table 5 below, and the four spatial stream boundaries indicated by index 35 in Table 5 are represented by 1222. Fig.11The positions of the four panels in the first MCS combination represent the four spatial stream boundaries indicated by the second field. The four spatial stream boundaries indicated by the second field are used to indicate the spatial streams corresponding to one or more MCSs in the first MCS combination. Fig.11 As shown, the first board = 1, the second board = 2, the third board = 2, the fourth board = 2, the first MCS corresponds to spatial stream ① (that is, spatial stream ① uses the first MCS), the second MCS corresponds to spatial stream ②, and the total number of spatial streams is 2. Fig.10 , the total number of spatial streams corresponding to the first MCS combination can be obtained by the position of the fourth board, that is, the total number of spatial streams is 2.

[0179] In one possible implementation, the second field is used to indicate the number of spatial streams corresponding to one or more MCSs in the first MCS combination. An example of the second field being used to indicate the number of spatial streams corresponding to one or more MCSs in the first MCS combination is: the second field is used to indicate the spatial stream boundary corresponding to any MCS in the first MCS combination. In other words, the second field is used to indicate the spatial stream boundary of any MCS in the first MCS combination. The spatial stream boundary corresponding to an MCS can be an integer, and the spatial stream boundary corresponding to the first MCS in the first MCS combination represents the number of spatial streams corresponding to the first MCS; the difference between the spatial stream boundary corresponding to the mth MCS in the first MCS combination and the spatial stream boundary corresponding to the (m-1)th MCS is the number of spatial streams corresponding to the mth MCS, and m is an integer greater than or equal to 2. For example, the value of the second field represents index 175 in Table 5 below, and the four spatial stream boundaries indicated by the index 175 are represented by 2 4 5 8, where 2 represents the spatial stream boundary corresponding to the first MCS, 4 represents the spatial stream boundary corresponding to the second MCS, 5 represents the spatial stream boundary corresponding to the third MCS, and 8 represents the spatial stream boundary corresponding to the fourth MCS. The four spatial stream boundaries indicate that the first MCS corresponds to 2 spatial streams (that is, 2 spatial streams use the first MCS), the second MCS corresponds to 2 spatial streams, the third MCS corresponds to 1 spatial stream, and the fourth MCS corresponds to 3 spatial streams. For ease of understanding, the four spatial stream boundaries indicated by the second field can be understood as the positions of the four boards that divide the multiple spatial streams corresponding to the first MCS combination. The four boards correspond to four MCSs, a first MCS with a number of streams less than or equal to the first board, a second MCS with a number of streams greater than the first board and less than or equal to the number of streams of the second board, a third MCS with a number of streams greater than the second board and less than or equal to the number of streams of the third board, and a fourth MCS with a number of streams greater than the third board and less than or equal to the number of streams of the fourth board.

[0180] Reuse Fig. 9, the value of the second field represents index 175 in Table 5 below, and the four spatial stream boundaries indicated by index 175 in Table 5 (i.e., the four spatial stream boundaries indicated by the second field) are represented by 2 4 5 8, Fig. 9 The positions of the four panels in the second field indicate the four spatial stream boundaries. Fig. 9 As shown, the first board = 2, the second board = 4, the third board = 5, the fourth board = 8, the first MCS corresponds to 2 spatial streams, the second MCS corresponds to 2 spatial streams, the third MCS corresponds to 1 spatial stream, and the fourth MCS corresponds to 3 spatial streams. Multiplexing Fig.10 , the value of the second field represents index 169 in Table 5 below, the four spatial stream boundaries indicated by index 169 in Table 5 (that is, the four spatial stream boundaries indicated by the second field) are represented by 2 4 4 6, the first board = 2, the second board = 4, the third board = 4, the fourth board = 6, the first MCS corresponds to 2 spatial streams, the second MCS corresponds to 2 spatial streams, the second MCS corresponds to 0 spatial streams, the fourth MCS corresponds to 2 spatial streams, and the total number of spatial streams is 6.

[0181] An example of the second field being used to indicate the number of spatial streams corresponding to one or more MCSs in the first MCS combination is: the second field is used to indicate the number of spatial streams corresponding to each MCS in the first MCS combination. In this example, the second field is also used to indicate the total number of spatial streams corresponding to the first MCS combination, and the total number of spatial streams corresponding to the first MCS combination is the sum of the number of spatial streams corresponding to each MCS in the first MCS combination. Exemplarily, the first MCS combination includes g types of MCSs, and the value of the second field represents an index, which indicates G1G2...Gg, G1 represents the number of spatial streams corresponding to the first MCS, G2 represents the number of spatial streams corresponding to the second MCS, ..., Gg represents the number of spatial streams corresponding to the g-th MCS. G1, G2, ..., Gg are all integers greater than 0, and G is an integer greater than 1. g is an integer greater than 0. The receiving end can determine the MCS corresponding to each spatial stream according to the number of spatial streams corresponding to each MCS in the first MCS combination. For example, G1=2 indicates that the spatial streams corresponding to the first MCS are the 1st and 2nd spatial streams, G2=2 indicates that the spatial streams corresponding to the second MCS are the 3rd and 4th spatial streams (i.e., the 3rd and 4th spatial streams) starting from the last spatial stream (the 2nd spatial stream) corresponding to G1; G3=0 indicates that the spatial streams corresponding to the third MCS are the 0th spatial stream starting from the last spatial stream (the 4th spatial stream) corresponding to G2; G4=2 indicates that the spatial streams corresponding to the fourth MCS are the 5th and 6th spatial streams (i.e., the 5th and 6th spatial streams) starting from the last spatial stream (the 4th spatial stream) corresponding to G3. In summary, the spatial streams represented by Gi correspond to the i-th MCS in the first MCS group in sequence, and the spatial stream represented by Gi corresponding to the i-th MCS is the Gi spatial stream starting from the last spatial stream corresponding to Gi-1. i is an integer greater than or equal to 1, Gi is greater than or equal to 2; the spatial streams represented by G1 corresponding to the first MCS are the first spatial stream to the G1th spatial stream.

[0182] In the above-mentioned embodiment, one MCS combination includes four MCSs, and the four spatial stream boundaries indicated by the second field (which can be regarded as four plates) are used to indicate the spatial streams corresponding to one or more MCSs in the first MCS combination. It should be noted that the embodiment of the present application can be extended to an MCS combination including M MCSs, and the second field indicates M spatial stream boundaries to indicate the case where the maximum number of spatial streams is N. The embodiment of the present application does not limit the values ​​of M and N. M is an integer greater than 0, and N is an integer greater than 0.

[0183] In a possible implementation, the value of the second field is an index, and the index is any index in the spatial stream grouping index table. The spatial stream grouping index table can be called a UEQM spatial stream grouping index table, and the name of the spatial stream grouping index table is not limited. Any index (defined) in the spatial stream grouping index table is used to indicate M spatial stream boundaries. The spatial stream grouping index table includes a correspondence between multiple indexes and spatial stream boundaries. The maximum number of spatial streams corresponding to different spatial stream grouping index tables is different. Examples of several spatial stream grouping index tables are shown below. Table 5 is an example of a spatial stream grouping index table provided in an embodiment of the present application. The maximum number of spatial streams supported by Table 5 for UEQM is 8, that is, an index in Table 5 corresponds to a maximum of 8 spatial streams. The spatial stream grouping index tables (including Table 5) shown in this article are only partial examples. For example, a spatial stream grouping index table may include only some entries in Table 5. In addition, the correspondence between the index in the spatial stream grouping index table and the spatial stream boundary is not limited. Refer to Table 5 below, where index 0 corresponds to 1 1 1 2 representing 4 spatial stream boundaries. In some possible spatial stream grouping index tables, index 0 corresponds to 1 1 1 3 representing 4 spatial stream boundaries. It is uniformly explained here that a table obtained by adding, deleting, deforming, or modifying the correspondence between indexes and spatial stream boundaries on the basis of the spatial stream grouping index tables (e.g., Tables 5 to 10) shown in this document belongs to the spatial stream grouping index table protected by this application. An example of a deformation of the spatial stream grouping index table (e.g., Tables 5 to 10) is as follows: the first and second columns in the spatial stream grouping index table remain unchanged, the values ​​of each row in the third column are changed to the values ​​of each row in the third column minus the values ​​in the corresponding rows in the second column, the values ​​of each row in the fourth column are changed to the values ​​of each row in the fourth column minus the values ​​in the corresponding rows in the third column, and so on. In the deformed spatial stream grouping index table, the value in the column where the mth MCS is located is the number of spatial streams corresponding to the mth MCS, and m is an integer greater than 0. For example, 2 4 5 8 indicated by index 175 in Table 5 is transformed into 2 2 1 3, and 2 2 1 3 respectively represent the number of spatial streams corresponding to the first MCS, the number of spatial streams corresponding to the second MCS, the number of spatial streams corresponding to the third MCS, and the number of spatial streams corresponding to the fourth MCS. For another example, 2 4 4 6 indicated by index 169 in Table 5 is transformed into 2 2 0 2. Here, only one example of the deformation of the spatial stream grouping index table (such as Tables 5 to 10) is shown, and the spatial stream grouping index table can be deformed in other forms. Since the deformed spatial stream grouping index table and the undeformed spatial stream grouping index table can both be used to determine the MCS corresponding to the spatial stream, the deformed spatial stream grouping index table and the undeformed spatial stream grouping index table can be regarded as equivalent.

[0184] Table 5

[0185]

[0186]

[0187]

[0188]

[0189]

[0190]

[0191]

[0192]

[0193] Taking index 175 in Table 5 as an example, the four spatial stream boundaries indicated by index 175 are represented by 2 4 5 8 respectively, that is, the spatial stream boundary corresponding to the first MCS is 2, the spatial stream boundary corresponding to the second MCS is 4, the spatial stream boundary corresponding to the third MCS is 5, and the spatial stream boundary corresponding to the fourth MCS is 8. The spatial streams corresponding to one or more MCSs in the first MCS combination indicated by the four spatial stream boundaries indicated by index 175 are as follows: Fig. 9 Taking index 169 in Table 5 as an example, the four spatial stream boundaries indicated by index 169 are represented by 2 4 4 6, that is, the spatial stream boundary corresponding to the first MCS is 2, the spatial stream boundary corresponding to the second MCS is 4, the spatial stream boundary corresponding to the third MCS is 4, and the spatial stream boundary corresponding to the fourth MCS is 6. The spatial streams corresponding to one or more MCSs in the first MCS combination indicated by the four spatial stream boundaries indicated by index 169 are as follows: Fig.10 Taking index 35 in Table 5 as an example, the four spatial stream boundaries indicated by index 35 are represented by 1 2 2 2, that is, the spatial stream boundary corresponding to the first MCS is 1, the spatial stream boundary corresponding to the second MCS is 2, the spatial stream boundary corresponding to the third MCS is 2, and the spatial stream boundary corresponding to the fourth MCS is 2. The spatial streams corresponding to one or more MCSs in the first MCS combination indicated by the four spatial stream boundaries indicated by index 35 are as follows: Fig.11 As shown, no further details are given here.

[0194] Table 6 is an example of another spatial stream grouping index table provided in an embodiment of the present application. The maximum number of spatial streams supported by Table 6 for UEQM is 4, that is, one index in Table 6 corresponds to a maximum of 4 spatial streams.

[0195] Table 6

[0196]

[0197]

[0198] Taking index 9 in Table 6 as an example, the four spatial stream boundaries indicated by index 9 are represented by 1 2 2 2, that is, the spatial stream boundary corresponding to the first MCS is 1, the spatial stream boundary corresponding to the second MCS is 2, the spatial stream boundary corresponding to the third MCS is 2, and the spatial stream boundary corresponding to the fourth MCS is 2. The spatial streams corresponding to one or more MCSs in the first MCS combination indicated by the four spatial stream boundaries indicated by index 9 are as follows: Fig.11 As shown, no further details are given here.

[0199] Assuming that the maximum number of spatial streams supported by UEQM is 4, the second field can occupy 5 bits. Compared with the MCS indication (4 bits) under EQM modulation, only 1 bit is required to ensure approximately the same length. Exemplarily, by using reserved bits or beamforming bits, it is easy to achieve equal length of user fields under EQM and UEQM.

[0200] In order to further reduce the number of entries in the spatial stream grouping index table, the number of spatial streams corresponding to the same MCS indicated by one index in the spatial stream grouping index table can be limited to be less than or equal to the first threshold. In one possible implementation, the number of spatial streams corresponding to the same MCS indicated by the second field is less than or equal to the first threshold, and the first threshold is a positive integer less than 8. Exemplarily, the first threshold is any one of 4, 5, 6, and 7. Because, if the number of streams corresponding to a certain MCS (i.e., the number of spatial streams) exceeds the first threshold, EQM can be used, or two MCSs can be used instead. Table 7 is an example of another spatial stream grouping index table provided in an embodiment of the present application, and the maximum number of spatial streams supported by UEQM in Table 7 is 8. The number of spatial streams corresponding to the same MCS indicated by each index in Table 7 is less than or equal to 4. Table 7 can be understood as being obtained by optimizing Table 5 using the optimization method 1. Optimizing Table 5 using the optimization method 1 means removing (deleting) one or more indexes in Table 5, and the number of spatial streams corresponding to the same MCS indicated by the one or more indexes is greater than the first threshold.

[0201] Table 7

[0202]

[0203]

[0204]

[0205]

[0206]

[0207]

[0208]

[0209]

[0210] By comparing Table 7 and Table 5, it can be seen that the optimization method 1 is adopted. Compared with Table 7, Table 5 reduces 321-276=45 entries, which reduces the complexity of both the transmitting and receiving ends. If some entries are further deleted from Table 7, the number of entries in the spatial stream grouping index table can be reduced to less than 256. When the number of entries in the spatial stream grouping index table used by the transceiver (transmitter and receiver) is reduced to less than 256, the length of the second field can be 8 bits.

[0211] Further, by limiting the number of spatial streams corresponding to one or more MCSs indicated by the second field to at most one MCS corresponding to an odd number of spatial streams, the entries in the spatial stream grouping index table can be reduced. Exemplarily, the number of spatial streams corresponding to at most one MCS among the number of spatial streams corresponding to one or more MCSs indicated by the second field is an odd number. For example, among the number of spatial streams corresponding to the M types of MCSs indicated by the second field, the number of spatial streams corresponding to the first MCS to the number of spatial streams corresponding to the (M-1)th MCS are all even numbers, the number of spatial streams corresponding to the Mth MCS is an even number or an odd number, and M is an integer greater than 0. For example, optimizing Table 5 using optimization method 2, optimizing Table 5 using optimization method 2 means removing (deleting) one or more indexes in Table 5, and the number of spatial streams corresponding to at least two MCSs among the number of spatial streams corresponding to one or more MCSs indicated by the one or more indexes is an odd number. Table 8 is an example of another spatial stream grouping index table provided in an embodiment of the present application, and the maximum number of spatial streams supported by Table 8 for UEQM is 8. Table 8 is obtained by optimizing Table 5 using optimization method 1 and optimization method 2. In other words, Table 8 is obtained by optimizing Table 7 using the second optimization method.

[0212] Table 8

[0213]

[0214]

[0215] The number of entries in Table 8 is 12, which greatly reduces the complexity of both the transmitting and receiving ends. When the spatial stream grouping index table used is Table 8, the length of the second field may be 6 bits.

[0216] Optimizing the spatial stream grouping index table (e.g., Table 7) using optimization method 2 will prohibit (or delete) the situation where each MCS in the spatial stream grouping index table corresponds to one spatial stream, that is, the situation where each spatial stream uses a different MCS. Exemplarily, the situation where each MCS corresponds to one spatial stream can be added back to Table 8 as a special case, which is referred to as optimization method 3. Table 9 is an example of another spatial stream grouping index table provided in an embodiment of the present application. The maximum number of spatial streams supported by Table 9 for UEQM is 8. Table 9 can be obtained by optimizing Table 8 using optimization method 3, that is, the situation where each MCS corresponds to one spatial stream is added back to Table 8.

[0217] Table 9

[0218]

[0219]

[0220]

[0221] In a possible implementation, one or more indexes in the spatial stream grouping index table indicate EQM and the number of spatial streams under EQM, and the one or more indexes can be understood as the spatial stream number indication of EQM. When some indexes in the spatial stream grouping index table indicate spatial stream boundaries (e.g., index 0 in Table 10), and some indexes indicate EQM and the number of spatial streams under EQM (e.g., index 31 in Table 10), that is, UEQM and EQM use a unified spatial stream allocation indication field, that is, the second field, the indication of EQM / UEQM can be saved.

[0222] Table 10 is an example of another spatial stream grouping index table provided in an embodiment of the present application. The maximum number of spatial streams supported by Table 10 for UEQM is 4. Table 10 may be an EQM transmission with 1 to 8 spatial streams corresponding to indexes 31-38 added on the basis of Table 6. For example, index 31 indicates an EQM with a spatial stream number of 1, and index 32 indicates an EQM with a spatial stream number of 2. In the present application, a row in a table is an entry. There is no restriction on the order of the entries in Table 10. For example, indexes 31-38 may also be at the front of Table 10, that is, index 0 indicates NSS=1, EQM. The number of indexes indicating EQM and the number of spatial streams under EQM in Table 10 is not limited. For example, the last index in Table 10 is 31. For another example, the last index in Table 10 is 34.

[0223] Table 10

[0224]

[0225]

[0226] In a possible implementation, the second field is used to indicate the number of spatial streams corresponding to an MCS in the first MCS combination, or the second field is used to indicate the number of spatial streams corresponding to multiple MCSs in the first MCS combination. Exemplarily, when the value indicated by the second field is the first index, the second field is used to indicate the number of spatial streams corresponding to an MCS in the first MCS combination, and when the value indicated by the second field is the second index, the second field is used to indicate the number of spatial streams corresponding to multiple MCSs in the first MCS combination. The second field is used to indicate the number of spatial streams corresponding to an MCS in the first MCS combination, which may be: The second field is used to indicate EQM and the number of spatial streams under EQM. For example, the first index is any one of index 0 to index 30 in Table 10, and the second index is any one of index 31 to index 38 in Table 10. In this article, the value indicated by a field may be the value of the field.

[0227] In a possible implementation, the first SIG field in the PPDU includes a user field, and the user field includes the second field. The user field in the first SIG field has two possible formats. Fig.12 Another example of the format of the first SIG field in the PPDU provided in an embodiment of the present application. Fig.12 Two formats of user fields are shown, one format includes STA ID, UEQM MCS combination indication field (i.e., the first field), NSS combination indication field (i.e., the second field mentioned above), beamforming subfield (optional), and coding subfield, and the other format includes STA ID, MCS field, NSS combination indication field, reserved field (optional), beamforming subfield (optional), and coding subfield. Fig.12 For more information about the fields in Figure 4 Description of the fields in . Fig.12 The lengths of the user fields in the two formats shown may be equal or unequal. Fig.12 It is shown that the sum of the length of the NSS combination indication field in the user field corresponding to the EQM and the length of the reserved field is equal to the length of the NSS combination indication field in the user field corresponding to the UEQM. Fig.12 The formats of the two user fields shown are only examples. The format of the user field in the first SIG field may also be other formats, that is, Fig.12The formats of the user fields shown are different. For example, the lengths of the NSS combination indication fields in the above two user fields are equal, and the length of the MCS field is equal to the length of the UEQM MCS combination indication field. For another example, the lengths of the NSS combination indication fields in the above two user fields are equal, and the length of the UEQM MCS combination indication field (i.e., the first field) is equal to the sum of the length of the MCS field and the length of the reserved field (optional). For another example, the lengths of the NSS combination indication fields in the above two user fields are equal, and the sum of the length of the UEQM MCS combination indication field (i.e., the first field) and the length of the reserved field is equal to the sum of the length of the MCS field and the length of the reserved field (optional).

[0228] In a possible implementation, the first SIG field in the PPDU includes a user field in format 1 and a user field in format 2. The user field in format 1 includes the second field and the EQM MCS combination indication field, and the user field in format 2 includes the second field and the MCS field. Exemplarily, the user field in format 1 is used to indicate that the spatial stream of the user associated with the user field adopts UEQM, and the user field in format 2 is used to indicate that the spatial stream of the user associated with the user field adopts EQM. There are two possible formats for the user field in the first SIG field. Fig.13 Another example of the format of the first SIG field in the PPDU provided in an embodiment of the present application. Fig.13 Two formats of user fields are shown. One user field (i.e., the user field using format 1) includes STA ID, UEQM MCS combination indication field (i.e., the first field), NSS combination indication field (i.e., the second field mentioned above), beamforming subfield (optional), and coding subfield. The other user field (i.e., the user field using format 2) includes STA ID, MCS field, NSS combination indication field, reserved field (optional), beamforming subfield (optional), and coding subfield. Fig.13 For more information about the fields in Figure 6 Description of the fields in . Fig.12The lengths of the user fields of the two formats shown are equal or unequal. Exemplarily, the length of the UEQM MCS combined indication field (i.e., the first field) is equal to the sum of the length of the MCS field and the length of the reserved field (optional). Exemplarily, the length of the UEQM MCS combined indication field (i.e., the first field) is equal to the length of the MCS field. Exemplarily, the sum of the length of the UEQM MCS combined indication field (i.e., the first field) and the length of the reserved field is equal to the sum of the length of the MCS field and the length of the reserved field (optional). When the lengths of the user fields of the above two formats are equal, the receiving end does not need to know the length of the user field when parsing the user field, making the operation of parsing the user field easier to implement.

[0229] It should be noted that the user field provided in this application supports non-MU-MIMO transmission format, that is, one RU is allocated to one user. Exemplarily, when the user field in the PPDU supports the MU-MIMO transmission format, the PPDU can adopt the EQM modulation mode.

[0230] The following describes how the receiving end parses the above user fields.

[0231] The receiving end can first obtain EQM / UEQM through the spatial stream grouping index table, that is, obtain the number of spatial streams under EQM / the spatial stream boundary under UEQM, and then read the MCS field / UEQM MCS combination indication field. Exemplarily, the implementation method of the receiving end parsing the user field that matches its own association identifier (association identifier, AID) is as follows: the receiving end reads the NSS combination indication field and obtains the index represented by the NSS combination indication field; obtains the spatial stream boundary or EQM and the number of spatial streams under EQM indicated by the index; when the index indicates the spatial stream boundary, obtains the MCS combination indicated by the UEQM MCS combination indication field; according to the MCS combination indicated by the UEQM MCS combination indication field and the spatial stream boundary indicated by the index, determines the number of spatial streams corresponding to one or more MCSs in the MCS combination; when the index indicates EQM and the number of spatial streams under EQM, reads the MCS field, and the MCS indicated by the MCS field is the MCS used by each spatial stream of the receiving end.

[0232] The following takes the index in Table 10 represented by the NSS combination indication field in the user field as an example to introduce an example of parsing the user field at the receiving end.

[0233] For example, the value of the NSS combination indication field in the user field is 31, that is, the NSS combination indication field indicates index 31; the receiving end knows that its spatial stream adopts EQM and the number of spatial streams is 1 according to index 31 and the above Table 10, and then reads the MCS field to learn an MCS, that is, the MCS adopted by its spatial stream. An example of the receiving end reading the MCS field and learning an MCS is: the receiving end obtains the value of the MCS field to represent index #1, and reads the MCS indicated by index #1 in Table 3 or Table 4. For another example, the value of the NSS combination indication field in the user field is 15, that is, the NSS combination indication field indicates index 15; the receiving end knows that its spatial stream adopts UEQM and the spatial stream boundaries corresponding to the four MCSs according to index 15 and the above Table 10, and then reads the UEQM MCS combination indication field to learn an MCS combination; according to the MCS combination and the spatial stream boundaries corresponding to the four MCSs, the number of spatial streams corresponding to one or more MCSs in the MCS combination is determined. An example in which the receiving end reads the UEQM MCS combination indication field to obtain an MCS combination is as follows: the receiving end obtains the value of the UEQM MCS combination indication field indicating index #2, and reads the MCS combination indicated by index #2 in Table 2 or Table 4.

[0234] Fig.14 Another modulation and coding strategy indication method interaction flow chart provided in the embodiment of the present application. Fig.14 As shown, the method includes:

[0235] 1401. The transmitter generates a PPDU.

[0236] The PPDU includes a sixth field and a seventh field. The sixth field is used to indicate the number of spatial streams of a third user (for example, one or more sites). A user may be a group of users in multicast transmission. Exemplarily, the value of the sixth field indicates the number of spatial streams of a third user (a site). The sixth field may be replaced by NSS (number of spatial streams). In this article, the number of spatial streams of a user refers to the number of spatial streams adopted by the user. The seventh field is used to indicate the MCS adopted by each spatial stream of the third user. The seventh field may be called a UEQM MCS field or may be called other fields. The MCS adopted by the spatial stream indicated by the seventh field is related to the number of spatial streams of the third user. The MCS adopted by the spatial stream indicated by the seventh field is related to the number of spatial streams of the third user, which may be: when the number of spatial streams of the third user is different, the MCS adopted by the spatial stream indicated by the seventh field is different. For example, the number of spatial streams of the third user is 2, and the seventh field indicates the MCS adopted by the two spatial streams of the third user. For another example, the number of spatial streams of the third user is 3, and the seventh field indicates the MCS adopted by the three spatial streams of the third user. Exemplarily, the value of the seventh field is an index, and the index is used to indicate the MCS respectively adopted by each spatial stream of the third user.

[0237] In a possible implementation, the PPDU includes one or more user fields, and one user field includes the sixth field and the seventh field. Exemplarily, one user field in the PPDU is associated with one user (e.g., a site), and one user field includes information that the user associated with the user field needs to read, and other users do not need to read the user field. For example, a user field in the PPDU is associated with user #3, and the user field includes the identifier of user #3. User #3 determines that the user field contains the information that it needs to read based on the identifier of user #3 included in the user field. Other users (e.g., sites) ignore (disregard) the user field when the identifier included in the user field is not their own identifier.

[0238] The following describes a case where the PPDU includes one user field and a case where the PPDU includes multiple user fields.

[0239] In one possible implementation, the PPDU includes a user field, which includes a sixth field, a seventh field, and an eighth field (optional). Among them, the eighth field is used to indicate EQM or UEQM. The eighth field can be called an EQM / UEQM indication field or an EQM / UEQM field. For example, when the value of the EQM / UEQM field is 0, the EQM / UEQM field is used to indicate EQM; when the value of the EQM / UEQM field is 1, the EQM / UEQM field is used to indicate UEQM. Fig.15 This is an example of the format of the user field in the PPDU provided in the embodiment of the present application. Fig.15 As shown, the user fields in the PPDU include: STAID, EQM / UEQM field (optional), UEQM MCS field (i.e., the seventh field), NSS (i.e., the sixth field), beamforming subfield (optional), and coding subfield. Fig.15 For a description of the fields in the User Fields section, see Figure 3 Description of each field in the User Fields shown. Fig.15 The user field shown is only an example of a user field in the PPDU. Fig.15The user field shown may include more or fewer fields. For example, the user field in the PPDU includes STAID, UEQM MCS field, NSS, and coding subfield. The embodiment of the present application does not limit the length and position of each field in the user field in the PPDU. For example, the length of the sixth field may be 2 bits, 3 bits, 4 bits, etc. For example, the length of the seventh field may be 5 bits, 6 bits, 7 bits, 8 bits, 9 bits, etc. Exemplarily, in the user field of the PPDU, the length of the EQM / UEQM field is 1 bit, the length of the UEQM MCS field is 7 bits, and the length of the NSS is 2 bits. Exemplarily, in the user field of the PPDU, the length of the EQM / UEQM field is 1 bit, the length of the UEQM MCS combination indication field is 9 bits, and the length of the NSS is 3 bits.

[0240] In a possible implementation, the PPDU includes a first SIG field, and the first SIG field includes the user field. The PPDU may be Figure 7 or Figure 8 The PPDU shown. The above-mentioned first SIG field may be any field in the UHRPPDU. Exemplarily, the above-mentioned first SIG field is the UHR-SIG field in the UHRPPDU. Exemplarily, the above-mentioned first SIG field is the L-SIG field in the UHRPPDU. The above-mentioned first SIG field may be any field in the IMMWPPDU. Exemplarily, the above-mentioned first SIG field is the IMMW-SIG field in the IMMWPPDU. Exemplarily, the above-mentioned first SIG field is the L-SIG field in the IMMWPPDU.

[0241] Fig.16 Another example of the format of the first SIG field in the PPDU provided in the embodiment of the present application. Fig.16 As shown, the first SIG field includes a common field and a user-specific field, and the user-specific field includes the above-mentioned user field, CRC field, tail bits, and padding bits (optional). Fig.16 The description of each field of the first SIG field can be found in Figure 4 Description of the fields of the first SIG field is shown. Fig.16 The format of the first SIG field shown is for single-user transmission, that is, the first SIG field includes one user field.

[0242] In a possible implementation, the transmitting end may send a PPDU (hereinafter referred to as PPDU#3) including the sixth field (NSS) and the seventh field (UEQM MCS field), for example, the user field of the PPDU#3 includes the sixth field and the seventh field, the user field of the PPDU#3 is associated with user#3, the sixth field is used to indicate the total number of spatial streams of user#3, and the seventh field is used to indicate the MCS used by each spatial stream of user#3; and may also send a PPDU (hereinafter referred to as PPDU#4) including the MCS field and the NSS, for example, the user field of the PPDU#4 includes the MCS field and the NSS, the user field of the PPDU#4 is associated with user#4, the NSS is the total number of spatial streams of user#4, and the MCS field is used to indicate the same MCS used by each spatial stream of user#4. That is, the transmitting end may send two PPDUs of different formats, the user field in one PPDU includes the UEQM MCS field, and the user field in the other PPDU includes the MCS field and the NSS. When the user field of the PPDU includes the UEQMMCS field and the NSS, the spatial stream of the user associated with the user field adopts UEQM; when the user field of the PPDU includes the MCS field and the NSS, the spatial stream of the user associated with the user field adopts EQM. That is, when the spatial stream of a user adopts UEQM, the user field in the PPDU sent by the transmitter includes the above-mentioned UEQM MCS field and NSS to indicate the MCS adopted by each spatial stream of the user; when the spatial stream of a user adopts EQM, the user field in the PPDU sent by the transmitter includes the above-mentioned MCS field and NSS to indicate the same MCS adopted by each spatial stream of the user. Exemplarily, the user field in the PPDU sent by the transmitter includes the MCS field, the NSS, the eighth field (i.e., the EQM / UEQM field) and the coding subfield, and the eighth field is used to indicate EQM. Exemplarily, the first SIG field in the PPDU sent by the transmitter includes the user field, and the user field includes the MCS field, the NSS, the EQM / UEQM field and the coding subfield.

[0243] Fig.17 Another example of the format of the first SIG field in the PPDU provided in the embodiment of the present application. Fig.17 For a description of the fields in the first SIG field, see Figure 4 The description of the fields in the first SIG field is not repeated here. Fig.17, there are two possible formats for the user field in the first SIG field of the PPDU, and the lengths of the user fields of the two formats may be equal. One user field includes STA ID, EQM / UEQM field, UEQM MCS field, NSS, beamforming subfield (optional), and coding subfield, and the other user field includes STA ID, EQM / UEQM field, MCS field, reserved field (optional), NSS, beamforming subfield (optional), and coding subfield. Exemplarily, the length of the UEQM MCS field is equal to the sum of the length of the MCS field and the length of the reserved field (optional). For example, the position and length of the reserved field in the user field can be flexibly configured as needed so that the lengths of the two user fields are equal. Exemplarily, in one user field, the length of the UEQM MCS field is 7 bits; in another user field, the length of the MCS field is 4 bits, and the length of the reserved field is 3 bits. Exemplarily, in one user field, the length of the UEQM MCS field is 9 bits; in another user field, the length of the MCS field is 4 bits, and the length of the reserved field is 5 bits. The user field in this application can contain Fig.17 User fields may have more or fewer fields than shown.

[0244] In a possible implementation, the PPDU includes multiple user fields, s user fields among the multiple user fields include the UEQM MCS field and NSS, t user fields among the multiple user fields include the MCS field and NSS, NSS is used to indicate the number of spatial streams of a user (the user associated with the user field), and the MCS field is used to indicate that the same MCS is used for each spatial stream of the user, and the lengths of the user fields in the PPDU are equal or unequal. s is an integer greater than 0, and t is an integer greater than 0. That is, the PPDU may include user fields in two different formats. Taking the PPDU including the third user field (including the seventh field) and the fourth user field (including the MCS field) as an example, a PPDU including user fields in two different formats is introduced. Exemplarily, the third user field includes: STA ID, EQM / UEQM field, UEQMMCS field, NSS, beamforming subfield (optional), and coding subfield; the fourth user field includes: STA ID, EQM / UEQM field, MCS field, NSS, reserved field (optional), beamforming subfield (optional), and coding subfield.

[0245] There may be two formats of user fields in the PPDU, such as the third user field and the fourth user field. Any user field can indicate which type of user field it is through the EQM / UEQM field it contains, and the contents of the subfields in the user fields of different formats will be different. If the user fields of different formats in the PPDU are of equal length (that is, the lengths of the user fields of different formats are equal), the complexity of decoding and parsing at the receiving end can be simplified. Since the length of the UEQM MCS field is greater than the length of the MCS field, in order to make the third user field and the fourth user field equal or nearly equal in length, one way is to minimize the overhead of the UEQM MCS field to achieve a trade-off between overhead and flexibility. Another way is to introduce some reserved bits (for example) into the fourth user field. Fig.17 The position and length of the reserved field (or reserved bit) in the fourth user field are not limited. Exemplarily, the length of the UEQM MCS field is 7 bits; in the fourth user field, the length of the MCS field is 4 bits, and the length of the reserved field is 3 bits. Exemplarily, the length of the UEQM MCS field is 9 bits; in the fourth user field, the length of the MCS field is 4 bits, and the length of the reserved field is 5 bits. The user field in this application may contain more than Fig.17 The user fields shown are more or fewer fields. In the embodiment of the present application, EQM and UEQM can be implemented by user fields of different formats with equal lengths. The receiving end does not need to know the length of the user field when parsing the user field, making the operation of parsing the user field easier to implement.

[0246] In a possible implementation manner, the first SIG field in the PPDU includes the third user field and the fourth user field, and the format of the first SIG field in the PPDU is for OFDMA transmission. Fig.18 Another example of the format of the first SIG field in the PPDU provided in the embodiment of the present application. Fig.18 As shown, the first SIG field includes a common field and a user-specific field, the user-specific field includes a plurality of user block fields, and a user block field includes one or two user fields, CRC, and tail bits. Fig.18 The description of the fields in the first SIG field can be found in the Figure 6 Descriptions of the fields in the first SIG field are shown. Fig.18 The first user field in may be an example of the fourth user field mentioned above. Fig.18 The second user field in can be an example of the third user field mentioned above. Fig.18As shown, the first user field (i.e., the fourth user field) corresponds to EQM, and the first user field includes STAID, EQM / UEQM field, MCS field, NSS, reserved field (optional), beamforming subfield (optional), and coding subfield; the second user field (i.e., the fourth user field) corresponds to UEQM, and the second user field includes STA ID, EQM / UEQM field, UEQM MCS field, NSS, beamforming subfield (optional), and coding subfield. Exemplary, Fig.18 The lengths of the user fields in the PPDU shown are equal.

[0247] In a possible implementation, the PPDU includes a plurality of user fields, and the plurality of user fields include a third user field and a fourth user field. The format of the third user field is the same as the format of the fourth user field. The third user field is associated with a third user, and the fourth user field is associated with a fourth user. The seventh field included in the third user field is used to indicate that at least two spatial streams of the third user use different MCSs, and the seventh field included in the fourth user field is used to indicate that each spatial stream of the fourth user uses the same MCS. For example, the index represented by the value of the seventh field in the third user field is index 16 in Table 13 below, and the index represented by the value of the seventh field in the fourth user field is index 0 in Table 13 below. The length of the third user field is equal to the length of the fourth user field. Fig.19 Another example of the format of the first SIG field in the PPDU provided in the embodiment of the present application. Fig.19 The description of the fields in the first SIG field can be found in the Figure 6 Descriptions of the fields in the first SIG field are shown. Fig.19 The first user field in may be an example of the fourth user field. Fig.18 The second user field in can be an example of the third user field mentioned above.

[0248] 1402. The transmitter sends a PPDU.

[0249] Accordingly, the receiving end receives the PPDU. Exemplarily, when the PPDU is transmitted for a single user, one receiving end (i.e., the single user for which the PPDU is transmitted) receives the PPDU and parses the PPDU. Exemplarily, when the PPDU is transmitted for multiple users, multiple receiving ends (i.e., the users for which the PPDU is transmitted) receive the PPDU and parse the PPDU.

[0250] 1403. The receiving end obtains the MCS adopted by the spatial stream of the third user according to the PPDU.

[0251] In the embodiment of the present application, the seventh field is used to indicate the MCS used by each spatial stream of the third user, and the MCS used by the spatial stream indicated by the seventh field is related to the number of spatial streams of the third user; compared with indicating the MCS used by each spatial stream under different numbers of spatial streams through one index, the signaling overhead is less. In addition, the embodiment of the present application also balances the equal length of the user field under UEQM and EQM, simplifying the demodulation and parsing complexity of the device.

[0252] The following describes the indication method of the MCS adopted by the user's spatial stream in conjunction with the format of the user field.

[0253] An example of the format of the user field is Fig.17 As shown, the user field includes an EQM / UEQM field, an MCS field, and an NSS. Exemplarily, the MCS field indicates 16 entries as shown in Table 11 below. For example, the value of the MCS field is an index in Table 11, and the value range of the MCS field is 0 to 15. In Table 11, index 14 and index 15 are two special modulation modes, namely, a copy transmission mode and a BPSK modulation mode using dual-carrier modulation. The embodiments of the present application do not limit the order of the entries in Table 11 and the correspondence between the index and the MCS. The MCS field may indicate some of the entries in Table 11, for example, the value range of the MCS field is 0 to 11. For example, the user field in the PPDU includes the identifier of the fourth user, the EQM / UEQM field, the MCS field, and the NSS. The value of the EQM / UEQM field is 0 (indicating EQM), the value of the NSS is 3, the value of the MCS field is 4, the value of the NSS is the total number of spatial streams of the fourth user, and the MCS field (indicating index 4) is used to indicate that each spatial stream of the fourth user adopts 16-QAM and 3 / 4 code rate; the fourth user knows that its spatial stream adopts EQM based on the value of the EQM / UEQM field; then, it is known that the total number of its spatial streams is 3 based on the NSS, and that each spatial stream adopts 16-QAM and 3 / 4 code rate based on the MCS field.

[0254] Table 11

[0255]

[0256] Another example of the format of the user field is Fig.17As shown, the user field includes an EQM / UEQM field, a UEQMMCS field, and an NSS. Exemplarily, the value of the UEQM MCS field is an index, and the index corresponds to different tables under different NSSs. For example, when the value of the NSS in the user field is 2, the value of the UEQM MCS field is an index in the following Table 12. For another example, when the value of the NSS in the user field is 3, the value of the UEQM MCS field is an index in the following Table 13. If an index in a certain UEQM index table corresponds to L spatial streams, the UEQM index table is a UEQM index table with NSS=L, and L is an integer greater than 0. For example, Table 12 is a UEQM index table with NSS=2, and Table 13 is a UEQM index table with NSS=3. Tables 12 and 13 are examples of two UEQM index tables provided in this application. An index in the UEQM index table corresponds to the modulation mode of multiple spatial streams, and the multiple spatial streams use the same code rate. For example, an index in Table 12 corresponds to modulation modes respectively used by two spatial streams, and the two spatial streams use the same code rate.

[0257] In the UEQM index table, the modulation mode used by one spatial stream can be any one of 4096-QAM, 1024-QAM, 256-QAM, 64-QAM, 16-QAM, QPSK, BPSK, and the code rate used can be any one of 1 / 2, 2 / 3, 3 / 4, 5 / 6, 7 / 8, etc. In the UEQM index table shown below, the spatial stream uses a code rate of 1 / 2, 3 / 4, or 5 / 6, and BPSK is not introduced. Because the BPSK rate is low, the introduction of UEQM transmission does not improve the total throughput much. In addition, considering the overhead of the UEQM MCS field and the complexity caused by too many implementation types, the BPSK modulation method is not introduced. The modulation mode, code rate and index in the UEQM index table shown below are only an example. The UEQM index table used by the transceiver can be a part of the UEQM index table shown in this article, and the index can also use other corresponding methods, which is not limited in the embodiments of the present application. In addition, there may be some reserved entries in the UEQM index table. For example, the following Table 12 starts from 45 and reserves index 45 to index 63. Because for an index represented by N bits, a maximum of 2 to the power of N entries can be indicated. In addition, when the number of spatial streams is different, the UEQM MCS field of the same length is used, which simplifies the parsing at the receiving end. For UEQM index tables with a small number of spatial streams, there may also be many reserved entries. The embodiments of the present application introduce two types of reserved entries, namely Validate and Disregard. If the receiving end finds that an index indicates a confirmed entry, it will stop parsing the PPDU. If the receiving end finds that an index indicates an ignored entry, it will ignore the field and continue to read other fields.

[0258] Table 12

[0259]

[0260]

[0261] An index in Table 12 corresponds to the modulation modes respectively adopted by two spatial streams, and the two spatial streams adopt the same code rate. Each index in Table 12 indicates EQM modulation. The receiving end can learn the MCS respectively adopted by its two spatial streams according to Table 12. For example, the user field in the PPDU includes the identifier of the third user, the EQM / UEQM field, the UEQM MCS field, and the NSS. The value of the EQM / UEQM field is 1 (indicating UEQM), the value of the NSS is 2, the value of the UEQM MCS field is 4, and the value of the NSS is the total number of spatial streams of the third user; the third user knows that its spatial stream adopts UEQM according to the value of the EQM / UEQM field; then, according to the NSS, it is known that the total number of its spatial streams is 2, and the index indicated by the UEQM MCS field is the index in the UEQM index table of NSS=2; according to the UEQM MCS field and Table 12, the MCS respectively adopted by its two spatial streams are known.

[0262] Table 13

[0263]

[0264]

[0265]

[0266]

[0267] In Table 13, the meaning of index 0-index 15 may be the same as the meaning of index 0-index 15 in Table 11. In some possible implementations, index 0-15 may be used to indicate the modulation mode of EQM. Exemplarily, when the value of the UEQM MCS field represents index 0, the UEQM MCS field is used to indicate that each spatial stream of the third user adopts the BPSK modulation mode and 1 / 2 code rate; when the value of the UEQM MCS field represents index 16, the UEQM MCS field is used to indicate that the first spatial stream of the third user adopts the 16-QAM modulation mode and 1 / 2 code rate, the second spatial stream adopts the QPSK modulation mode and 1 / 2 code rate, and the third spatial stream adopts the QPSK modulation mode and 1 / 2 code rate. According to Table 13, the receiving end can know the MCS adopted by its three spatial streams respectively or the same MCS adopted by its three spatial streams. For example, the user field in the PPDU includes the identifier of the third user, the EQM / UEQM field, the UEQM MCS field, and the NSS. The value of the EQM / UEQM field is 0 (indicating EQM), the value of the NSS is 3, the value of the UEQM MCS field is 0, and the value of the NSS is the total number of spatial streams of the third user; the third user knows that its spatial stream uses EQM based on the value of the EQM / UEQM field; then, based on the NSS, it is known that the total number of its spatial streams is 3, and the index indicated by the UEQM MCS field is the index in the UEQM index table (for example, Table 13) where NSS=3; based on the UEQM MCS field and Table 13, it is known that the same MCS is used by its three spatial streams.

[0268] Table 14

[0269]

[0270]

[0271]

[0272]

[0273]

[0274]

[0275]

[0276]

[0277] Table 14 is an example of a UEQM index table with NSS=4.

[0278] In the UEQM index table shown above, the second spatial stream, the third spatial stream, and the fourth spatial stream can also be indicated by the difference from the first spatial stream, as shown in Table 15 below. In Table 15, the difference index is used to replace the various QANs corresponding to the second spatial stream, the third spatial stream, and the fourth spatial stream. For example, if the first spatial stream is reserved as QPSK, the difference value of 0 indicates 16-QAM, the difference value of 1 indicates 64-QAM, and the difference value of 2 indicates 256-QAM.

[0279] Table 15

[0280]

[0281] It can be seen from the above UEQM index table that as the NSS increases, the number of entries in the UEQM index table increases significantly. That is to say, when the NSS is different, the number of indexes contained in different UEQM index tables is different. For example, when NSS=2, the number of bits required for the UEQM MCS field is 6, see Table 12. For example, when NSS=3, the number of bits required for the UEQM MCS field is 8, see Table 13. For example, when NSS=4, the number of bits required for the UEQM MCS field is 9, see Table 14. When the value of NSS in the user field is different, the minimum number of bits required for the UEQM MCS field is different. If the length of the UEQM MCS field is defined according to the minimum number of bits required for the UEQM MCS field, the length of the user field under different numbers of spatial streams will be different.

[0282] Two possible methods for making the length of user fields under different numbers of spatial streams equal are described below.

[0283] One possible implementation is to define the length of the corresponding UEQM MCS field according to the number of bits required by the index number of the maximum number of streams. For example, the END of Table 12, Table 13, and Table 14 are all defined as 511, the length of the UEQM MCS field is 9 bits, and there are different numbers of reserved entries in Table 12, Table 13, and Table 14. Another possible implementation is that the length of the UEQM MCS field is different under different numbers of spatial streams, and additional reserved bits are used to align the user fields under different spatial streams. Exemplarily, under different numbers of spatial streams, the length of the UEQM MCS field and the length of the reserved field are as follows:

[0284] NSS=2, the length of the UEQM MCS field is 6 bits, and the length of the reserved field is (X+3) bits;

[0285] NSS=3, the length of the UEQM MCS field is 8 bits, and the length of the reserved field is (X+1) bits;

[0286] NSS=4, the length of the UEQM MCS field is 9 bits, and the length of the reserved field is X bits; where X is greater than or equal to 0.

[0287] Considering that the number of antennas of a terminal device (or station) is usually less than or equal to 4, it is possible to consider that the UEQM MCS field supports a maximum of 4SS (i.e., NSS = 4). Even so, the UEQM MCS field requires 9 bits, which means an additional 5 bits are required compared to the 4 bits of the MCS field. If you want to ensure that the above two different formats of user fields (see Fig.16 or Fig.17 ) to simplify the demodulation and analysis of the receiver. In the case of EQM modulation, multiple reserved bits need to be introduced, resulting in increased overhead. Therefore, it is necessary to consider how to save overhead, that is, to reduce the number of entries indicated by the UEQM MCS field.

[0288] The first way to reduce overhead is to limit the maximum modulation and the minimum modulation of the spatial stream used by the same user to not differ too much. Exemplarily, the difference between the highest MCS order and the lowest MCS order used by the spatial stream indicated by the seventh field is less than or equal to the second threshold, and the above-mentioned second threshold is a positive integer less than 10. For example, the highest modulation order minus the lowest modulation order used by the spatial stream indicated by the seventh field is less than or equal to 6. For example, when the lowest modulation used by a user's spatial stream is QPSK (order is 2), the highest modulation used by the user's spatial stream is 256-QAM (order is 8); when the lowest modulation used by a user's spatial stream is 16-QAM (order is 4), the highest modulation used by the user's spatial stream is 1024-QAM (order is 10); when the lowest modulation used by a user's spatial stream is 64-QAM (order is 6), the highest modulation used by the user's spatial stream is 4096-QAM (order is 12). The order of BPSK is 1. If the modulation order used by a user's spatial stream differs too much, the throughput gain brought by low modulation is not obvious. In order to balance the number of entries indicated by the UEQM MCS field (i.e., the number of indexes) and the increased complexity caused by too many receiver implementation modes, since 4SS has the largest number of entries, simplification can be performed for 4SS, or for all NSS to simplify the implementation of the receiver. Exemplarily, in order to reduce the number of entries indicated by the UEQM MCS field, optimization method 4 is used to optimize Table 14, that is, one or more indexes in Table 14 are removed (deleted), and the difference between the highest MCS order and the lowest MCS order used by the spatial stream indicated by the one or more indexes is greater than the second threshold. Table 16 can be obtained by optimizing Table 14 using optimization method 4. The difference between the highest MCS order and the lowest MCS order used by the spatial stream indicated by each index in Table 16 is less than or equal to 6, that is, the second threshold is 6.

[0289] Table 16

[0290]

[0291]

[0292]

[0293]

[0294]

[0295] By comparing Table 14 and Table 16, it can be seen that after optimizing Table 14 using optimization method 4, the number of entries in Table 14 is reduced by 376-223=153, and UEQM MCS saves 1 bit of overhead, that is, each user saves 1 bit of overhead.

[0296] The following describes a method for optimizing the UEQM index table through optimization method five. For EQM, different QAMs support different code rates. As shown in Table 11, QPSK and 16-QAM do not support 5 / 6 code rates, and 64-QAM and above do not support 1 / 2 code rates. Optimization method five can be to delete the modulation + code rate combinations that are not supported by EQM, that is, the bold entries in Tables 12-14, which can reduce the complexity of the transceiver. Exemplarily, the MCS used by the spatial stream indicated by the seventh field belongs to the MCS supported by EQM. Table 17 is an example of a UEQM index table that uses optimization method four and optimization method five at the same time. The MCS used by the spatial streams indicated by each index in Table 17 belongs to the MCS supported by EQM.

[0297] Table 17

[0298]

[0299]

[0300]

[0301]

[0302] Comparing Table 17 with Table 16, it can be seen that after optimizing Table 16 using optimization method 5, the number of entries in Table 16 is reduced by 223-118=105, and UEQM MCS saves 1 bit of overhead, that is, each user saves 1 bit of overhead.

[0303] The above describes designing a UEQM index table for different numbers of spatial streams. The following describes using the same UEQM index table to indicate all situations from 2SS to 4SS, including EQM and UEQM modulation methods. Table 18 is another example of a UEQM index table. Table 18 can simultaneously indicate NSS and the modulation methods of each spatial stream, including UEQM and UEQM. Exemplarily, the length of the UEQMMCS field is 10 bits, and the index represented by the value of the UEQM MCS field is any index in Table 18. Exemplarily, the user field includes STA ID, UEQM MCS field, beamforming subfield (optional), and coding subfield, see Fig. 20 . Fig. 20 This is an example of the format of the user field in the PPDU provided in the embodiment of the present application. Exemplarily, the first SIG field in the above PPDU includes multiple user fields, and the format of each user field is the same. For example, the format of the user field is as follows: Fig. 20 In addition, Table 18 can be further simplified by using optimization mode 4 and / or optimization mode 5 to reduce the modes that the device needs to support and the overhead of the signaling field. The bold entries in Table 18 are the modulation mode + code rate combinations that are not supported by EQM.

[0304] Table 18

[0305]

[0306]

[0307]

[0308]

[0309]

[0310]

[0311]

[0312]

[0313]

[0314]

[0315]

[0316]

[0317]

[0318]

[0319]

[0320]

[0321]

[0322] It is uniformly explained here that the tables obtained by adding, deleting, deforming, or modifying the UMCS index tables (such as Tables 12 to 18) shown in this document belong to the UMCS index tables protected by this application.

[0323] In addition, there are several methods for distinguishing whether the user field corresponds to EQM or UEQM. One is to use 1 bit or more than 1 bit for mode indication. For example, 1 bit (such as the EQM / UEQM field) is used to indicate whether it is EQM or UEQM. The indication can be located in the common field or in the user field. Furthermore, different indication methods can be used for EQM and UEQM. Exemplarily, EQM can use the existing standard method of indicating the MCS used for each spatial stream to simplify the implementation complexity of the device. Under EQM, the beamforming subfield is used to indicate whether the transmitting end has performed beamforming. One implementation method is that for UEQM, because beamforming is already used by default, under UEQM, the user field can use this subfield to carry the additional required UEQM MCS field.

[0324] It should be pointed out that in addition to UEQM for different spatial streams, the above method can also be used for UEQM modulation when a user is allocated more than one RU or MRU, and each spatial stream can be replaced with a different RU or MRU. Because RU or MRU has a predetermined frequency domain order, the entries in the table can be designed separately for different QAM sequences. For example, the entries corresponding to 16-QAM, QPSK are used to indicate that the frequency is from low to high, the first RU uses 16-QAM, and the second RU uses QPSK; the entries corresponding to QPSK, 16-QAM are used to indicate that the frequency is from low to high, the first RU uses QPSK, and the second RU uses 16-QAM.

[0325] The structure of a communication device that can implement the modulation and coding strategy indication method provided in an embodiment of the present application is described below in conjunction with the accompanying drawings.

[0326] Fig.21A schematic diagram of the structure of a communication device 2100 provided in an embodiment of the present application. The communication device 2100 may correspond to the functions or steps implemented by the transmitting end in the above-mentioned various method embodiments, and may also correspond to the functions or steps implemented by the receiving end in the above-mentioned various method embodiments. The communication device may include a processing module 2110 and a transceiver module 2120. Optionally, a storage unit may also be included, which may be used to store instructions (codes or programs) and / or data. The processing module 2110 and the transceiver module 2120 may be coupled to the storage unit, for example, the processing module 2110 may read the instructions (codes or programs) and / or data in the storage unit to implement the corresponding method. The above-mentioned modules may be independently arranged or partially or fully integrated. For example, the transceiver module 2120 may include a sending module and a receiving module. The sending module may be a transmitter, and the receiving module may be a receiver. The entity corresponding to the transceiver module 2120 may be a transceiver or a communication interface.

[0327] In some possible implementations, the communication device 2100 can implement the behaviors and functions of the transmitter in the above method embodiments. For example, the communication device 2100 can be a transmitter, or a component (such as a chip or circuit) used in the transmitter. The transceiver module 2120 can be used to perform Figure 2 , Fig.14 In the embodiment of the present invention, all receiving or sending operations performed by the sending end, such as Figure 2 In step 202 of the embodiment shown, Fig.14 Step 1402 of the illustrated embodiment, and / or other processes used to support the techniques described herein. Processing module 2110 is used to perform Figure 2 , Fig.14 In the embodiment of the present invention, all operations performed by the transmitting end except the sending and receiving operations, such as Figure 2 In step 201 of the embodiment shown, Fig.14 Step 1401 in the embodiment shown.

[0328] In some possible implementations, the communication device 2100 can implement the behaviors and functions of the receiving end in the above method embodiments. For example, the communication device 2100 can be a receiving end, or a component (such as a chip or circuit) used in the receiving end. The transceiver module 2120 can be used to perform Figure 2 , Fig.14 In the embodiment of the present invention, all receiving or sending operations performed by the receiving end, such as Figure 2 In step 202 of the embodiment shown, Fig.14Step 1402 in the illustrated embodiment, and / or other processes for supporting the techniques described herein. Processing module 2110 is used to execute all operations performed by the receiving end except for the sending and receiving operations, such as Figure 2 In step 203 of the illustrated embodiment, Fig.14 Step 1403 in the illustrated embodiment.

[0329] Fig. 22 A schematic diagram of the structure of another communication device 220 provided in an embodiment of the present application. Fig. 22 The communication device in the communication method may be the above-mentioned sending end or the above-mentioned receiving end.

[0330] like Fig. 22 As shown, the communication device 220 includes at least one processor 2210 and a transceiver 2220 .

[0331] In some embodiments of the present application, the processor 2210 and the transceiver 2220 may be used to execute the functions or operations executed by the transmitting end. The transceiver 2220 may, for example, execute Figure 2 , Fig.14 The processor 2210 is used to perform all receiving or sending operations performed by the transmitting end in the embodiment of the present invention. Figure 2 , Fig.14 All operations performed by the transmitting end except the sending and receiving operations in the embodiment.

[0332] In some embodiments of the present application, the processor 2210 and the transceiver 2220 may be used to execute the functions or operations executed by the receiving end. The transceiver 2220 may, for example, execute Figure 2 , Fig.14 The processor 2210 is used to execute all operations performed by the receiving end except the receiving and sending operations, such as Figure 2 In step 203 of the illustrated embodiment, Fig.14 Step 1403 in the illustrated embodiment.

[0333] The transceiver 2220 is used to communicate with other devices / apparatuses via a transmission medium. The processor 2210 uses the transceiver 2220 to send and receive data and / or signaling, and is used to implement the method in the above method embodiment. The processor 2210 can implement the functions of the processing module 2110, and the transceiver 2220 can implement the functions of the transceiver module 2120.

[0334] Optionally, the transceiver 2220 may include a radio frequency circuit and an antenna. The radio frequency circuit is mainly used for converting baseband signals and radio frequency signals and processing radio frequency signals. The antenna is mainly used for transmitting and receiving radio frequency signals in the form of electromagnetic waves. Input and output devices, such as a touch screen, a display screen, a keyboard, etc., are mainly used to receive data input by a user and output data to the user.

[0335] Optionally, the communication device 220 may further include at least one memory 2230 for storing program instructions and / or data. The memory 2230 is coupled to the processor 2210. The coupling in the embodiment of the present application is an indirect coupling or communication connection between devices, units or modules, which may be electrical, mechanical or other forms, and is used for information exchange between devices, units or modules. The processor 2210 may operate in conjunction with the memory 2230. The processor 2210 may execute program instructions stored in the memory 2230. At least one of the at least one memory may be included in the processor.

[0336] When the communication device 220 is turned on, the processor 2210 can read the software program in the memory 2230, interpret and execute the instructions of the software program, and process the data of the software program. When data needs to be sent wirelessly, the processor 2210 performs baseband processing on the data to be sent, and outputs the baseband signal to the radio frequency circuit. The radio frequency circuit performs radio frequency processing on the baseband signal and then sends the radio frequency signal outward in the form of electromagnetic waves through the antenna. When data is sent 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 2210. The processor 2210 converts the baseband signal into data and processes the data.

[0337] In another implementation, the above-mentioned RF circuit and antenna can be arranged independently of the processor performing baseband processing. For example, in a distributed scenario, the RF circuit and antenna can be arranged independently of the communication device in a remote manner.

[0338] The specific connection medium between the transceiver 2220, the processor 2210 and the memory 2230 is not limited in the embodiment of the present application. Fig. 22 The memory 2230, the processor 2210 and the transceiver 2220 are connected via a bus 2240. Fig. 22 The connection between other components is only for illustration and is not intended to be limiting. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Fig. 22 Only one thick line is used in the diagram, but this does not mean that there is only one bus or only one type of bus.

[0339] In the embodiments of the present application, the processor may be a general-purpose processor, a digital signal processor, an application-specific integrated circuit, a field programmable gate array or other programmable logic device, a discrete gate or transistor logic device, or a discrete hardware component, and may implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of the present application. The general-purpose processor may be a microprocessor or any conventional processor, etc. The steps of the method disclosed in the embodiments of the present application may be directly embodied as being executed by a hardware processor, or may be executed by a combination of hardware and software modules in the processor.

[0340] Fig.23 FIG. 2 is a schematic diagram of the structure of another communication device 230 provided in an embodiment of the present application. Fig.23 As shown, Fig.23 The communication device shown includes a logic circuit 2301 and an interface 2302 . Fig.21 The processing module 2110 in can be implemented by a logic circuit 2301. Fig.21 The transceiver module 2120 in the embodiment can be implemented with an interface 2302. The logic circuit 2301 can be a chip, a processing circuit, an integrated circuit or a system on chip (SoC) chip, etc., and the interface 2302 can be a communication interface, an input and output interface, etc. In the embodiment of the present application, the logic circuit and the interface can also be coupled to each other. The embodiment of the present application does not limit the specific connection method of the logic circuit and the interface.

[0341] In some embodiments of the present application, the logic circuit and interface may be used to execute the functions or operations performed by the above-mentioned transmitting end, etc.

[0342] In some embodiments of the present application, the logic circuit and interface may be used to execute the functions or operations performed by the above-mentioned receiving end, etc.

[0343] The present application also provides a computer-readable storage medium, in which a computer program or instruction is stored. When the computer program or instruction is executed on a computer, the computer executes the method of the above embodiment.

[0344] The present application also provides a computer program product, which includes instructions or a computer program. When the instructions or the computer program are run on a computer, the method in the above embodiment is executed.

[0345] The present application also provides a communication system, comprising the above-mentioned transmitting end and the above-mentioned receiving end.

[0346] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the above claims.

Claims

1. A modulation and coding strategy indication method, characterized in that: include: Generate a physical layer protocol data unit PPDU, the PPDU including a first field and a second field, the first field is used to indicate a first modulation and coding strategy MCS combination, and the second field is used to indicate the number of spatial streams corresponding to one or more MCSs in the first MCS combination; The PPDU is sent.

2. A modulation and coding strategy indication method, characterized in that: include: Receive a physical layer protocol data unit PPDU, the PPDU including a first field and a second field, the first field is used to indicate a first modulation and coding strategy MCS combination, and the second field is used to indicate a number of spatial streams corresponding to one or more MCSs in the first MCS combination; According to the PPDU, an MCS corresponding to each spatial stream is obtained.

3. The method according to claim 1 or 2, characterized in that: The second field is used to indicate a spatial stream boundary corresponding to any MCS in the first MCS combination.

4. The method according to claim 3, characterized in that The second field is also used to indicate the total number of spatial streams corresponding to the first MCS combination.

5. The method according to any one of claims 1 to 4, characterized in that: The number of spatial streams corresponding to the same MCS indicated by the second field is less than or equal to a first threshold, and the first threshold is a positive integer less than 8.

6. The method according to any one of claims 1 to 5, characterized in that: When the value indicated by the second field is the first index, the second field is used to indicate the number of spatial streams corresponding to one MCS in the first MCS combination; when the value indicated by the second field is the second index, the second field is used to indicate the number of spatial streams corresponding to multiple MCSs in the first MCS combination.

7. The method according to any one of claims 1 to 6, characterized in that: The PPDU also includes a third field, and the third field is used to indicate whether the modulation mode of the PPDU is unbalanced modulation or balanced modulation.

8. The method according to any one of claims 1 to 7, characterized in that: The PPDU includes a first user field and a second user field, the first user field is associated with a first user, the second user field is associated with a second user, the first user field includes the first field and the second field, the second user field includes a fourth field and a fifth field, the fourth field is used to indicate the number of spatial streams of the second user, the fifth field is used to indicate the same MCS used by each spatial stream of the second user, and the length of the first user field is equal to the length of the second user field.

9. A communication device, characterized in that: include: A processing module, configured to generate a physical layer protocol data unit PPDU, wherein the PPDU includes a first field and a second field, wherein the first field is used to indicate a first modulation and coding strategy MCS combination, and the second field is used to indicate a number of spatial streams corresponding to one or more MCSs in the first MCS combination; The transceiver module is used to send the PPDU.

10. A communication device, characterized in that: include: A transceiver module, configured to receive a physical layer protocol data unit PPDU, wherein the PPDU includes a first field and a second field, wherein the first field is used to indicate a first modulation and coding strategy MCS combination, and the second field is used to indicate a number of spatial streams corresponding to one or more MCSs in the first MCS combination; The processing module is used to obtain the MCS corresponding to each spatial stream according to the PPDU.

11. The device according to claim 9 or 10, characterized in that The second field is used to indicate a spatial stream boundary corresponding to any MCS in the first MCS combination.

12. The device according to claim 11, characterized in that The second field is also used to indicate the total number of spatial streams corresponding to the first MCS combination.

13. The device according to any one of claims 9 to 12, characterized in that The number of spatial streams corresponding to the same MCS indicated by the second field is less than or equal to a first threshold, and the first threshold is a positive integer less than 8.

14. The device according to any one of claims 9 to 13, characterized in that When the value indicated by the second field is the first index, the second field is used to indicate the number of spatial streams corresponding to one MCS in the first MCS combination; when the value indicated by the second field is the second index, the second field is used to indicate the number of spatial streams corresponding to multiple MCSs in the first MCS combination.

15. The device according to any one of claims 9 to 14, characterized in that The PPDU also includes a third field, and the third field is used to indicate whether the modulation mode of the PPDU is unbalanced modulation or balanced modulation.

16. The device according to any one of claims 9 to 15, characterized in that The PPDU includes a first user field and a second user field, the first user field is associated with a first user, the second user field is associated with a second user, the first user field includes the first field and the second field, the second user field includes a fourth field and a fifth field, the fourth field is used to indicate the number of spatial streams of the second user, the fifth field is used to indicate the same MCS used by each spatial stream of the second user, and the length of the first user field is equal to the length of the second user field.

17. A communication device, characterized in that: The method comprises a module for implementing the method according to any one of claims 1 to 8.

18. A communication device, characterized in that: The device comprises a processor, the processor is coupled to a memory, the memory stores computer program instructions, and the processor is used to execute the computer program instructions so that the communication device performs the method according to any one of claims 1 to 8.

19. A chip, characterized in that: It comprises a processor and a communication interface, wherein the processor reads instructions stored in a memory through the communication interface, and executes instructions so that a communication device including the chip executes the method according to any one of claims 1 to 8.

20. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, wherein the computer program includes program instructions, and when the program instructions are executed, the computer is enabled to perform the method according to any one of claims 1 to 8.

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