TW201918042A - Method of wireless communication and associated device - Google Patents

Abstract

Systems and methods of expanding indication capabilities of existent PPDU preamble fields. The "GI+LTF Size" field is redefined to indicate a new combination of GI duration and HE-LTF size. The redefinition is indicated when the values of the two other existent fields, in combination, indicate an invalid scenario because the two values should have been mutually exclusive. Particularly, the DCM field and the STBC field are both set to the "enabled" mode as an indication for redefine the "GI+LTF Size" field. Upon receiving such a PPDU, a receiver is configured to resolve the PPDU as neither DCM nor STBC is enabled. Rather, the receiver interprets the particular combination of DCM and STBC values as an indication that the "GI+LTF Size" field is redefined to indicate the new combination of GI duration and HE-LTF size.

Description

Wireless communication method and equipment

The present invention relates to the field of network communication, and particularly to the field of communication protocols in Wi-Fi network communication.

In efficient wireless communications, the preamble of the Protocol Data Unit (PPDU) of the Physical Layer Convergence Protocol (PLCP) may contain high efficiency (HE) long training fields. (Long training field, LTF) (HE-LTF) symbol, which can be used for channel estimation at the receiver. For example, the receiver may estimate a multiple input multiple output (MIMO) channel between a set of constellation mappers and a receiver chain based on the HE-LTF. Or, if the PPDU uses Space Time Block Coding (STBC), then the HE-LTF provides a method for the receiver to estimate the MIMO channel between the STBC encoder output and the receiver chain.

The IEEE802.11ax standards and specifications define the duration of HE-LTF through compression to optimize the performance of various scenarios. The HE physical layer can support LTF symbol durations of 3.2 μs (1x HE-LTF 1/4 compression), 6.4 μs (2x HE-LTF 1/2 compression), and 12.8 μs (4x HE-LTF uncompressed).

Between HE-LTF symbols, a guard interval (GI) is inserted, which is used to prevent, for example, inter-symbol interference (ISI) caused by echo or reflection in a channel. Inserting a GI between symbols makes it possible to resolve echo or reflection issues before the next symbol is transmitted.

The long GI between symbols can effectively prevent ISI, but because of the increase in idle time, it also inevitably increases the resource overhead (overhead). On the other hand, a short GI can increase the throughput of data transmission. However, if the GI is too short, the number of ISIs will increase, resulting in a decrease in the transmission throughput.

For communications that comply with the IEEE 820.11n / ac / ax standards and specifications, beamforming is already the most commonly used communication transmission mode. In beamforming, the compressed channel state information (CSI) feedback discards the common angle of each feedback vector. Therefore, in the beamforming scenario, for single user (SU) MIMO and multi-user (MU) MIMO, due to phase ambiguity between different subcarriers, 1x and 2x HE-LTF Sometimes it cannot be successfully inserted into 4x HE-LTF. Specifically, because of the many different channels, phase alignment does not guarantee that the interpolated channels match the actual channels. For some channels, the channel phase itself does not match the introduced alignment phase. In cases where phase alignment does not guarantee that the channel is inserted correctly, the usual solution is to use 4x LTF.

According to IEEE 802.11ax, 2 bits in the PPDU preamble are allocated to the "GI + LTF size" field to define 4 possible combinations of HE-LTF size and GI duration. That is, “GI + LTF size” = 0 means 1x HE-LTF and GI of 0.8 μs; “GI + LTF size” = 1 means 2x HE-LTF and 0.8μs GI; “GI + LTF size” = 2 Indicates 2x HE-LTF and GI of 1.6 μs; “GI + LTF size” = 3 indicates 4x HE-LTF and GI of 3.2 μs. These 4 modes represented by "GI + LTF size" are not the optimal combination for all types of PPDU transmission. In order to use 4x HE-LTF, all orthogonal frequency-division multiple access (OFDMA) symbols in the payload must use a GI of 3.2 μs. However, for most examples of SU MIMO or MU MIMO, the channel delay spread is shorter than 3.2 μs. Compared to a GI of 0.8 μs, using a GI of 3.2 μs reduces the data transmission rate by up to about 21%.

Unfortunately, all the preamble bits of the existing PPDU structure have been used or reserved for specific indications. Due to this limitation, it is difficult to introduce any additional HE-LTF / GI mode because the “GI + LTF size” column A bit has only 2 bits and cannot represent more than 4 combinations.

Therefore, the embodiments disclosed herein point to a mechanism that overcomes the bit length limitation of the "GI + LTF size" field and provides an indication of one or more additional modes of GI duration and HE-LTF size in the PLCP PPDU Without any changes to the existing PPDU structure.

The embodiment of the present application combines the field elements ("GI + LTF size" field) for indicating the GI / HE-LTF mode, and redefines two existing fields in the PPDU preamble signal as the GI duration and HE -An indication of a new mode of LTF size (or "GI / HE-LTF mode" here). Specifically, the values set by these two fields traditionally represent impossible or invalid scenarios by being combined together. When the receiver receives a PPDU, the specific combination of these two field values is interpreted as an indication (or part of an indication) of the new mode of GI / HE-LTF, and the original meaning indicated by these values alone is ignored.

In some embodiments, the Dual Sub-Carrier Modulation (DCM) field and the STBC field in the PPDU preamble signal are used to introduce a new mode of GI / HE-LTF size, which cannot be changed by the "GI Any value in the + LTF size field is represented separately. The new mode can be 4x HE LTF and GI of 0.8 μs or 1x HE LTF and GI of 0.4 μs. To indicate this new mode, the DCM field and the STBC field are both set to 1 (both are enabled), and, for example, the "GI + LTF size" field is set to 3. Since both DCM and STBC cannot be enabled for PPDUs, the receiver is configured to parse PPDUs as neither DCM nor STBC is enabled. More precisely, the receiver interprets the specific combination of DCM = 1 and STBC = 1 as an indication that the "GI + LTF size" field is being redefined. If the "GI + LTF size" field is set to 3, which itself indicates 4x LTF and GI of 3.2 μs, the receiver processes it as an indication of a new mode of 4x LTF and GI of 0.8 μs.

Therefore, according to the embodiment of the present application, by combining specific values of two other existing fields, a GI / HE-LTF mode that cannot be indicated by the “GI + LTF size” field alone can be advantageously indicated. This method advantageously uses existing fields in the PPDU preamble signal and expands the indicating capabilities of these fields. Therefore, an indication of a new operating mode or other specification is introduced without requiring any format or structure change in the existing PPDU preamble signal.

The present application provides the indication of one or more additional modes of GI duration and HE-LTF size by combining specific values of other existing fields in the PPDU preamble signal without any need to change the existing PPDU structure. Advantageously, existing fields in the PPDU preamble are effectively used, and the indicating ability of these fields is extended.

The foregoing is a summary of the invention, and therefore, only simplifications, generalizations, and details that are specifically described are necessary to be omitted. Those skilled in the art can understand that the content of the present invention is merely illustrative, and is not limited in any way. As limited only by the scope of the patent application, other aspects, inventive features, and beneficial effects of the present application will become apparent in the non-limiting specific embodiments described below.

The preferred embodiments of the present application are described in detail below, and examples thereof are shown in the following drawings. Although the present application will be described in conjunction with the preferred embodiments, it can be understood that these embodiments are not intended to limit the present application. On the contrary, the coverage substitution, modification, or equivalent made by this application may be included within the spirit and scope of this application as defined by the scope of the attached application patent. In addition, in the following detailed description of the embodiments of the present application, many specific details are explained in order to thoroughly understand the present application. However, those skilled in the art will recognize that this application can be implemented without these specific details. In other examples, well-known methods, procedures, components, and circuits are not described in detail in order to unnecessarily obscure aspects of the embodiments of the present application. Although a method may be described as multiple steps in the order for clarity, the numbers need not indicate the order of the steps. It should be understood that some steps may be skipped, performed concurrently, or performed without maintaining a strict sequence order. The drawings showing the embodiments of the present application are semi-illustrated, and will not be scaled, and specifically, some sizes are for clear display, and are shown enlarged in the drawings. Similarly, although the views in the drawings for convenience of description generally show similar directions, such descriptions in the drawings are arbitrary for the most part. Generally this application can be operated in any way.

Short guard interval (GI) indication mechanism in efficient WLAN

In general, the embodiments of the present application provide a mechanism for extending the indication capability of the existing PPDU preamble field. In some embodiments, the "GI + LTF size" field is redefined to indicate a new pattern (or redefined pattern) of GI duration and HE-LTF size. This redefinition can be indicated when the values of two other existing fields are combined to indicate an invalid scenario, because these two values should be mutually exclusive.

With reference to the PLCP PPDU structure defined in the IEEE 802.11 family, the embodiments of the present application will be described in detail. However, this application is not limited to any particular data packet format or structure, nor is it limited to any particular industry standard or specification.

FIG. 1 illustrates an exemplary HE SU PPDU field for indicating an additional redefined GI / HE-LTF mode of a PPDU according to an embodiment of the present application. As defined in the IEEE 802.11ax standards and specifications, it is assumed that the "GI + LTF size" field has 2 bits, and as shown in Table 1, the field itself can only represent the GI duration and the LTF size of Kinds of fixed combinations. Table 1

The DCM field has 1 bit and is used to indicate whether the DCM is applied to the data field for the indicated Modulation and Coding Scheme (MCS). When the DCM field is set to 1, it indicates that the DCM is applied (enabled); and when the DCM field is set to 0, it indicates that the DCM is not applied. DCM is only applied to MCS0, MCS 1, MCS 3, and MCS 4. The STBC field has 1 bit, and when this field is set to 1, it is usually used to indicate that the space-time block coding (STBC) is used on the PPDU. If STBC is applied, DCM is not applied. In this example, the GI + LTF size field 111, the DCM field 112, and the STBC field 113 are all included in the HE-SIG-A field 110 included in the PPDU preamble signal.

As mentioned above, it is desirable to use other combinations of GI duration and LTF size, for example, 4x HE-LTF and GI durations shorter than 3.2 μs. According to the embodiment of the present application, as shown in FIG. 1, both the DCM field 112 and the STBC field 113 are set to 1 to indicate that the “GI + LTF size” field 111 is redefined to indicate that except for those shown in Table 1. Combinations other than the four combinations shown. Therefore, the HE-LTF field 120 in the PPDU is configured to the indicated combination.

Since the DCM enablement and the STBC enablement are mutually exclusive for the PPDU, the receiver is configured to parse the PPDU carrying the DCM = 1 and STBC = 1 as neither the DCM nor the STBC is enabled. More precisely, the receiver advantageously interprets the combination of DCM = 1 and STBC = 1 as an indication that the "GI + LTF size" field is being redefined. For example, if the "GI + LTF size" field is set to 3 (as shown), it itself originally represents 4x LTF and 3.2 μs GI, but the receiver interprets it as a new 4x LTF and 0.8 μs GI Indication of the mode. If the "GI + LTF size" field is set to 0, it itself originally represents 1x LTF and 0.8 μs GI, but the receiver interprets it as an indication of a new mode of 1x LTF and 0.4 μs GI. It can be understood that, without departing from the scope of the present application, any other redefinition pattern of GI duration and LTF size may be indicated by the DCM field element, the STBC field, and the "GI + LTF size" field. In addition, the application is not limited to using the DCM field and the STBC field to indicate the redefinition of the "GI + LTF size" field. To implement the present invention, various appropriate fields initially assigned to indicate other specifications may also be used.

Therefore, according to the embodiment of the present application, by combining specific values of two other existing fields, a GI / HE-LTF mode that cannot be represented by the “GI + LTF size” field element alone can be advantageously indicated. This approach advantageously makes it possible to effectively use existing fields in the PPDU preamble signal and expand the indicating capabilities of these fields. Therefore, new operating modes or other specification indications can be introduced without requiring changes to any existing format or structure in the PPDU preamble.

FIG. 2 is a flowchart describing an exemplary process 200 for generating a PPDU including redefining the “GI + LTF size” field according to an embodiment of the present application. The process 200 may be performed by a relevant element in the transmitter device, for example, a wireless access point (AP) station (STA) or a non-AP STA. In this example, it is assumed that the “GI + LTF size” field, the DCM field, and the STBC field are all assigned the same pointing function as described with reference to FIG. 1.

In step 201, a redefined GI / HE-LTF mode (for example, 4x HE-LTF and 0.8 μs GI) using a PPDU is determined, which mode is not included in the "GI + LTF size" which can be composed of 2 bits alone The field represented by the pattern. For example, because PPDUs will be transmitted in MIMO transmissions, this redefined mode is selected. However, the application is not limited to this application.

In step 202, according to the redefinition, the "GI + LTF size" field is set to the redefined value to indicate the desired selection of the HE-LTF size. For example, in this example, the "GI + LTF size" field is set to 3, which represents 4x LTF. In 203, the DCM field is set to indicate the enable of the DCM on the payload of the PPDU (for example, DCM = 1), and the STBC field is set to indicate the enable of the STBC on the payload of the PPDU (for example, STBC = 1). Since the enable of DCM and STBC on the payload are invalid scenarios, the enable state setting indicates that neither the DCM nor STBC of the payload is enabled, but indicates the value in the "GI + LTF size" field New mode for indicating GI / HE-LTF combination. In this example, when DCM = 1 and STBC = 1, “GI + LTF size” = 3 does not represent 4x LTF and 3.2 μs GI according to the original definition, but represents 4x LTF and 0.8 μs according to the redefinition. GI. As another example, when DCM = 1 and STBC = 1, “GI + LTF size” = 0 can be used to indicate 1x LTF and GI of 0.4 μs.

Therefore, in step 204, the HE-LTF field of the PPDU is generated by using the redefinition mode (for example, 4x LTF and GI of 0.8 μs). In step 205, the PPDU is transmitted through the wireless network in the SU MIMO transmission. This application may also be used for other suitable types of transmissions, such as MU-MIMO transmissions.

FIG. 3 is a flowchart describing an exemplary process 300 for parsing a PPDU with a redefined “GI + LTF size” field according to an embodiment of the present application. The process 300 may be performed by a relevant element in the receiver device, for example, an AP STA or a non-AP STA. For example, the received PPDU comes from the PPDU generation and transmission process described with reference to FIG. 2. In this example, it is assumed that the “GI + LTF size” field, the DCM field, and the STBC field are all assigned the same indication function as described with reference to FIGS. 1 and 2.

In step 301, a PPDU packet is received at a receiver. In step 302, the receiver detects that the DCM field in the PPDU preamble signal is set to indicate the DCM enable on the PPDU payload (eg, DCM = 1) and the STBC field is set to indicate the PPDU payload. STBC is enabled (for example, STBC = 1). In response, the receiver interpreted the PPDU as neither DCM nor STBC was enabled. In step 303, according to the redefinition of the "GI + LTF size" field, the receiver also determines whether the field is set to a valid value. For example, in this example, when DCM = 1 and STBC = 1, only "GI + LTF size" = 3 is a valid value. In this way, in step 304, if it is detected that the "GI + LTF size" field is not set to a valid value, then a PPDU error is declared. In step 305, if the "GI + LTF size" field indicates a valid value, the receiver, especially the channel estimator, uses a redefined GI / HE-LTF mode, for example, 4x LTF and GI of 0.8 μs, Parse the HE-LTF field. The payload data was interpreted as neither DCM nor STBC was enabled.

The process 200 and the process 300 may be implemented as software logic, hardware logic, firmware logic, or a combination thereof.

FIG. 4 is a structural diagram illustrating a configuration of an exemplary wireless communication device 400 for generating a PPDU having a redefined GI / HE-LTF mode according to an embodiment of the present application. The device 400 may be an AP STA or a non-AP STA, and may transmit a PPDU to another device through a wireless LAN. The device 400 is configured to generate a PPDU using the redefined GI duration and HE-LTF size, wherein the redefined GI duration and HE-LTF size cannot be represented by the "GI + LTF size" field alone.

The device 400 may be a general-purpose computer and any other type of computing device or network device, including a main processor 430, a memory 420, and a transceiver 440 coupled to an array of antennas 401-404. The transceiver 440 includes a signal processor 410 having various modules of a transmission path for generating each part of the PPDU or any other type of communication transmission unit. For example, the signal processor 410 includes a transmit first-in-first-out (TX FIFO) 411, an encoder 412, a scrambler 413, an interleaver 414, a constellation mapper 415, and an inverse discrete Fourier transform. (Inversed discrete Fourier transformer (IDFT)) 417 and GI and window insertion module 416.

The memory 420 stores a PPDU format 421, which includes a format with a redefined "GI + HE-LTF size" field. The PPDU generation module 422 stores processor-executable instructions for generating a data sequence and configuration of other parts of the PPDU according to the PPDU format 421. As specifically described in connection with FIG. 1 and FIG. 2, the PPDU generation module 422 may decide to use the redefined GI / HE-LTF mode, and the signal processor 410 generates the preamble signal and the HE-LTF field accordingly.

FIG. 5 is a structural diagram illustrating a configuration of an exemplary wireless communication device 500 for parsing a received PPDU with a redefined GI / HE-LTF mode according to an embodiment of the present application. The device 500 may be an AP STA or a non-AP STA, and may transmit a PPDU to another device through a wireless LAN. The device 500 is configured to parse the received PPDU using a combination of the redefined GI duration and the HE-LTF size, which cannot be represented by the "GI + LTF size" field alone.

The device 500 may be a general-purpose computer and any other type of computing device or network device, including a main processor 530, a memory 520, and a transceiver 540 coupled to an array of antennas 501-514. The transceiver 540 includes a signal processor 510 having various modules of a transmission path for processing PPDUs or any other type of communication transmission unit. For example, the signal processor 510 includes a receive first-in-first-out (RX FIFO) 511, a synchronizer 512, a channel evaluator and equalizer 513, a decoder 514, and a demapper 515. , A deinterleaver 516, a fast Fourier transformer (FFT) 517, and a descrambler 518.

The memory 520 stores a PPDU format 521, and the PPDU format 521 includes a format for redefining the "GI + HE-LTF size" field. The PPDU processing module 522 stores processor-executable instructions for analyzing different parts of the PPDU (including the preamble signal) according to the PPDU format 521. As specifically described in connection with Figures 1 and 3, as long as the signal processor 510 detects that the DCM field, the STBC field, and the "GI + HE-LTF size" field are combined to represent a redefined GI / HE- In the LTF mode, the signal processor 510 processes the preamble signal and the HE-LTF field based on the instructions from the PPDU processing module 522.

It is understood that the signal processors in FIGS. 4 and 5 may include other suitable components in a broad range known in the art. The different elements may be implemented in any suitable manner known in the art and may be implemented using hardware logic, software logic, or a combination thereof. In addition, in some embodiments, the transceiver 410 in FIG. 4 may also include elements in the receiving path as specifically described in connection with the transceiver 510 in FIG. 5, and vice versa.

Although this application discloses some preferred embodiments and methods, it is obvious to those skilled in the art based on the above disclosure that these embodiments and methods can be modified or modified without departing from the spirit and scope of this application. . This application is limited only by the provisions and principles of applicable law and the content required by the scope of the accompanying patent application. The above description is only a preferred embodiment of the present invention, and all equivalent changes and modifications made in accordance with the scope of patent application of the present invention shall fall within the scope of the present invention.

111‧‧‧GI + LTF size field

112‧‧‧DCM field

113‧‧‧STBC field

110‧‧‧HE-SIG-A field

120‧‧‧HE-LTF field

200, 300‧‧‧ flow

201 ~ 205, 301 ~ 305‧‧‧ steps

400, 500‧‧‧ wireless communication equipment

430, 530‧‧‧ main processor

440, 540‧‧‧ Transceivers

420, 520‧‧‧Memory

401 ~ 404, 501 ~ 504‧‧‧antenna

410, 510‧‧‧‧ signal processor

411‧‧‧TX FIFO

412‧‧‧ Encoder

413‧‧‧Scrambler

414‧‧‧Interleaver

415‧‧‧ Constellation Mapper

417‧‧‧ Inverse Discrete Fourier Transformer

416‧‧‧GI and Window Insertion Module

421‧‧‧PPDU format

422‧‧‧PPDU generation module

511‧‧‧RX FIFO

512‧‧‧Synchronizer

513‧‧‧Channel Estimator and Equalizer

514‧‧‧ decoder

515‧‧‧ demapper

516‧‧‧ Deinterleaver

517‧‧‧Fast Fourier Transformer

518‧‧‧Descrambler

521‧‧‧PPDU format

522‧‧‧PPDU processing module

FIG. 1 illustrates an exemplary HE SU PPDU field for a GI / HE-LTF mode representing a redefined PPDU according to an embodiment of the present application. FIG. 2 is a flowchart describing an exemplary process of generating a PPDU including redefining the “GI + LTF size” field according to an embodiment of the present application. FIG. 3 is a flowchart describing an exemplary process of parsing a PPDU with a redefined “GI + LTF size” field according to an embodiment of the present application. FIG. 4 is a structural diagram illustrating a configuration of an exemplary wireless communication device for generating a PPDU with a redefined GI / HE-LTF mode according to an embodiment of the present application. FIG. 5 is a schematic structural diagram illustrating a configuration of an exemplary wireless communication device for parsing a received PPDU with a redefined GI / HE-LTF mode according to an embodiment of the present application.

Claims (25)

A wireless communication method includes: setting a first field of a Physical Layer Convergence Protocol (PLCP) protocol data unit (PPDU) to indicate a selected high-efficiency long training field (high efficiency long training field (HE-LTF) mode; according to the first field: setting a second field of the PPDU to indicate a Dual Sub-Carrier Modulation (DCM) on the data field of the PPDU ); And setting a third field of the PPDU to indicate the enabling of Space Time Block Coding (STBC) on the data field of the PPDU, wherein the first Two fields are set to indicate the enabling of the DCM; and the PPDU is transmitted. The wireless communication method according to item 1 of the scope of patent application, wherein the selected HE-LTF mode includes a 4x HE-LTF mode, wherein the first field is set and the second field is set with the first field The three fields make the first field also indicate a guard interval (GI) of less than 3.2 μs. The wireless communication method according to item 2 of the scope of patent application, wherein setting the first field and setting the second field and the third field makes the first field also indicate protection of 0.8 μs interval. The wireless communication method according to item 1 of the scope of patent application, wherein the first field, the second field, and the third field are included in the HE-SIG-A field of the PPDU. . The wireless communication method according to item 1 of the scope of patent application, wherein the combination of the first field, the second field, and the third field obtained from a plurality of settings does not indicate that the PPDU DCM enable does not indicate STBC enable. The wireless communication method according to item 1 of the scope of patent application, wherein the transmission includes transmitting the PPDU in a single-user transmission. A wireless communication method includes: receiving a physical layer convergence protocol PLCP protocol data unit PPDU; and in response to the receiving, determining that a first field in the PPDU indicates a 4x high-efficiency long training field HE-LTF; The receiving, determining that the second field in the PPDU indicates the enabling of the dual subcarrier modulation DCM on the data field of the PPDU; in response to the receiving, determining that the third field in the PPDU indicates the Enable the block code STBC on the data field of the PPDU, wherein the second field of the PPDU indicates the enabling of the DCM on the data field; and based on a plurality of the determinations, pass The guard interval GI of less than 3.2 μs is used to parse the HE-LTF field of the PPDU. The wireless communication method according to item 7 of the scope of patent application, wherein the parsing includes parsing the PPDU by using a guard interval equal to 0.8 μs. The wireless communication method according to item 7 of the patent application scope, further comprising: determining: the first field in the PPDU indicates a non-4x HE-LTF mode; the second field in the PPDU A bit indicates the enabling of the DCM on the data field of the PPDU; and the third field in the PPDU indicates the enabling of the STBC on the data field of the PPDU; and Declares an error in the PPDU. The wireless communication method according to item 7 of the scope of patent application, wherein the parsing includes: parsing the PPDU to neither DCM nor STBC based on the determination, but not applied to the PPDU. A wireless communication device for transmitting a protocol data unit PPDU over a wireless communication network. The device includes: a memory; a processor coupled to the memory; an antenna; and a transceiver, the transceiver including a signal processor And coupled to the processor, the memory, and the antenna, the transceiver is configured to: set a first field of a physical layer convergence protocol PLCP protocol data unit PPDU to indicate a selected high-efficiency long training field Bit HE-LTF mode; setting the second field of the PPDU to indicate the enable of the dual subcarrier modulation DCM on the data field of the PPDU; setting the third field of the PPDU to indicate the PPDU Enable the space-time block code STBC on the data field, wherein the second field of the PPDU is set to indicate the enable of the DCM; and send the PPDU to the antenna to The transmission on the wireless communication network is described. The wireless communication device according to item 11 of the scope of patent application, wherein the selected HE-LTF mode includes a 4x HE-LTF mode. The wireless communication device according to item 11 of the scope of patent application, wherein the first field also indicates a guard interval of less than 3.2 μs. The wireless communication device according to item 11 of the scope of patent application, wherein the first field also indicates a guard interval of 0.8 μs. The wireless communication device according to claim 11, wherein the first field, the second field, and the third field are included in a preamble signal of the PPDU, and a plurality of The obtained combination of the first field, the second field, and the third field indicates neither the DCM enablement nor the STBC enablement on the PPDU. The wireless communication device according to item 11 of the patent application scope, wherein the PPDU is transmitted in a single user transmission. A wireless communication device is used to receive a protocol data unit PPDU through the wireless communication device. The device includes: a memory; a processor coupled to the memory; and a transceiver including a signal processor and configured to: The physical layer convergence protocol PLCP protocol data unit PPDU transmitted by the wireless network; in response to receiving the PPDU, detecting that the first field in the PPDU indicates the selected high-efficiency long training field element HE-LTF mode; responding to receiving Detecting, in the PPDU, a second field in the PPDU indicating the enabling of the dual subcarrier modulation DCM on the data field of the PPDU; and in response to receiving the PPDU, determining a third field in the PPDU Indicating the enabling of the space-time block code STBC of the PPDU, wherein the second field of the PPDU indicates the enabling of the DCM on the data field; and based on the first field, the The second field and the third field parse the PPDU by using a guard interval GI of less than 3.2 μs. The wireless communication device according to item 17 of the scope of patent application, wherein the transceiver is configured to parse the PPDU by using a guard interval equal to 0.8 μs. The wireless communication device according to item 17 of the scope of patent application, wherein the selected HE LTF mode includes a 4x HE LTF mode. The wireless communication device according to item 17 of the scope of patent application, wherein the transceiver is further configured to determine that: the first field in the PPDU indicates a non-4x HE-LTF mode; The second field indicates the enabling of the DCM on the data field of the PPDU; and the third field in the PPDU indicates the STBC on the data field of the PPDU. Enable, wherein the second field of the PPDU indicates the enabling of the DCM on the data field; and based on the first field, the second field, and the third field , Claiming an error in the PPDU. The wireless communication device according to item 17 of the scope of patent application, wherein the transceiver is further configured to, based on the determination, parse the PPDU into that neither DCM nor STBC is enabled on the data field. A wireless communication method, comprising: receiving a physical layer convergence protocol PLCP protocol data unit PPDU; determining that a received dual subcarrier modulation DCM field in the PPDU indicates the enabling of the DCM on the data field of the PPDU, And determine that the space-time block code STBC field in the received PPDU indicates that the STBC is enabled on the data field of the PPDU; determine the guard interval + long training field GI + in the received PPDU Whether the LTF size field is set to a valid value; and if the GI + LTF size field in the PPDU is set to a valid value, the efficient length of the PPDU is parsed by using the redefined GI and LTF modes Training field HE-LTF field. The wireless communication method according to item 22 of the scope of patent application, wherein the effective value indicates that the value of the GI + LTF size field is 3. The wireless communication method according to item 23 of the scope of patent application, wherein the redefined GI and LTF size modes indicate a 4x HE-LTF mode and a GI of 0.8 μs. The wireless communication method according to item 22 of the scope of patent application, wherein if it is determined that the GI + LTF size field in the received PPDU is set to a non-valid value, an error is declared in the PPDU.