Method for Transmitting a Physical Layer Protocol Data Unit and Communication Device

Abstract

The present application provides a method and a communication device for transmitting a PPDU. The method can be applied to some scenarios where PPDU alignment needs to be implemented. For example, in a multi-link transmission with non-simultaneous transmission and reception, it needs to be guaranteed that the time error of the simultaneous end of multiple PPDUs does not exceed 8 microseconds. In the method, a transmitter controls the duration of one or more fields of a PE field, an EHT-SIG field, and an EHT-LTF field of a PPDU, and / or delays the transmission time of the PPDU, so that the error between the end time of the PPDU and a specific time (e.g., a first time) is not larger than an error threshold, thereby implementing PPDU alignment. The present application is applied to a wireless local area network system supporting a next-generation IEEE 802.11ax Wi-Fi protocol, for example, an 802.11 series protocol such as 802.11be or EHT.

Description

Technical Field

[0001] The present application relates to the field of wireless local area networks. More specifically, it relates to a method and a communication apparatus for transmitting a physical layer protocol data unit in a wireless local area network.

[0002] This application claims the benefit of priority to Chinese Patent Application No. 202110949948.1, titled "METHOD FOR SENDING PHYSICAL LAYER PROTOCOL DATA UNIT AND COMMUNICATION APPARATUS", filed with the China National Intellectual Property Administration on August 18, 2021, the entire content of which is incorporated herein by reference.

Background Art

[0003] The wireless local area network (WLAN) has evolved from 802.11a / b / g and is progressing to 802.11be, which is being discussed in the industry, starting from 802.11n, 802.11ac, and 802.11ax. Currently, there are two EHT PPDU formats defined in 802.11be. That is, the extremely high throughput multiple user physical layer protocol data unit (EHT MU PPDU) and the extremely high throughput trigger-based physical layer protocol data unit (EHT TB PPDU). The EHT MU PPDU can support single-user (downlink or uplink) and multi-user (downlink) data transmissions. The EHT TB PPDU is a PPDU that is triggered to be transmitted by one or more stations (STAs) based on the scheduling information within the trigger frame transmitted by an access point (AP).

[0004] However, in current wireless communications, there are many scenarios where PPDU alignment is required. Specifically, the time interval between the PPDU end time and the target end time is less than a specific error threshold. For example, in non-simultaneous transmit and receive (non-STR) multi-link (ML) transmission, the time error related to the simultaneous ending of PPDUs on multiple links (e.g., Link 1 and Link 2) is generally required not to exceed 8 microseconds. However, when there are trigger frames in the PPDUs on different links and carrier monitoring is performed before the transmission of the TB PPDU triggered by the trigger frame, the time error related to the simultaneous ending of PPDUs on different links is generally required not to exceed 4 microseconds.

[0005] However, in the existing coding procedures of the EHT MU PPDU and the existing EHT TB PPDU, time limitations are not considered. For example, the PPDUs on different links are encoded based on the respective required durations. In the current situation, the requirements regarding PPDU alignment cannot be met. SUMMARY OF THE INVENTION

[0006] This application provides a method and a communication device for transmitting a PPDU to implement PPDU alignment.

[0007] According to a first aspect, a method for transmitting a PPDU is provided. This method may be applied to a transmitter for wireless communication, or may be applied to a chip or a chip system of the transmitter. The following uses the transmitter as an example. In this method, The transmitter controls the duration of one or more of the packet extension (PE) field, the extremely high throughput signal (EHT-SIG) field, and the extremely high throughput long training field (EHT-LTF) field of the first PPDU, and / or delays the transmission time of the first PPDU so that the error between the end time of the first PPDU and the first time does not exceed an error threshold, and the transmitter transmits the first PPDU. This method

[0008] In the technical solution of this application, the transmitter controls the duration of one or more of the PE field, the EHT-SIG field, and the EHT-LTF field of a PPDU (for example, the first PPDU) so that the error between the end time of the PPDU and a specific time (for example, the first time) does not exceed an error threshold, and / or delays the transmission time of the PPDU to align the end time of the PPDU with the first time.

[0009] The solution in this application is applicable to some scenarios with time constraints (or scenarios where PPDU alignment is required), for example, the transmission of PPDUs in non-STR ML transmission.

[0010] Referring to the first aspect, in some implementations of the first aspect, the first PPDU includes a preamble, a data field, and the PE field, the duration of the PE field is determined based on a first duration, the duration of the preamble of the first PPDU, and the duration of the symbols in the data field, and the first duration is the duration between the first time and the start time of the first PPDU.

[0011] In this implementation, considering that the duration granularity of the PE field is a multiple of 4 microseconds, the alignment between the end time of the first PPDU and the first time is implemented by using the duration of the PE field. This can meet the alignment requirements with a relatively small error threshold. For example, the error threshold is 4 microseconds or 8 microseconds.

[0012] Referring to the first aspect, in some implementations of the first aspect, the number of symbols in the data field is determined based on a first duration, the duration of the preamble, and the duration of the symbols in the data field.

[0013] Referring to the first aspect, in some implementations of the first aspect, the first PPDU includes a preamble, a data field, and the PE field, the preamble includes the EHT-SIG field, and the EHT-SIG field includes an initial portion and a padding portion.

[0014] The duration of the padding portion in the EHT-SIG field is determined based on a first duration, the initial duration of the preamble, the duration of the PE field, and the duration of the symbols in the data field, the initial duration of the preamble does not include the duration of the padding portion in the EHT-SIG field, and the first duration is the duration between the first time and the start time of the first PPDU.

[0015] The duration of the padding portion is a multiple of 4 microseconds.

[0016] In this implementation, considering that the duration of one symbol in the EHT-SIG field is 4 microseconds and that the EHT-SIG field enables all symbols to be padding bits, the EHT-SIG field is padded, and as a result, the end time of the first PPDU can be aligned with the first time. In addition, compared to the alignment of the first PPDU by using the PE field, the duration of the PE field can be shortened. And the selection of the pre-forward error correction padding factor can be simplified.

[0017] Referring to the first aspect, in some implementations of the first aspect, the number of symbols in the data field is determined based on the first duration, the initial duration of the preamble, the duration of the PE field, and the duration of the symbols in the data field.

[0018] Referring to the first aspect, in some implementations of the first aspect, the EHT-SIG field of the first PPDU carries a low-density parity-check LDPC additional symbol segment field, the LDPC additional symbol segment field is set to a second value, the EHT-SIG field carries a second pre-forward error correction padding factor, the second value indicates that no LDPC additional symbol segment needs to be added, the LDPC additional symbol segment field is set when the LDPC additional symbol segment condition is not met, and the LDPC additional symbol segment condition is set based on the second pre-forward error correction padding factor. The second pre-forward error correction padding factor is determined based on the duration of the PE field and the nominal packet padding ability of the receiver.

[0019] In one implementation, the transmitter selects the duration of the PE field of the first PPDU based on a limit for the first time. Further, the transmitter selects a second pre-forward error correction padding factor based on the selected duration of the PE field and the nominal packet padding ability of the receiver, determines whether the LDPC additional symbol segment condition is satisfied based on the second pre-forward error correction padding factor, and sets the LDPC additional symbol segment field if the LDPC additional symbol segment condition is not satisfied. In this implementation, the first PPDU End time The alignment between End time and the first time can be guaranteed. And the transmission of the PPDU in a scenario where PPDU alignment is required can be satisfied.

[0020] Referring to the first aspect, in some implementations of the first aspect, the EHT-SIG field of the first PPDU carries the LDPC additional symbol segment field, where the LDPC additional symbol segment field is set to be a first value, the EHT-SIG field carries the second pre-forward error correction padding factor, the first value indicates that an LDPC additional symbol segment needs to be added, the LDPC additional symbol segment field is set when the LDPC additional symbol segment condition is satisfied, and the LDPC additional symbol segment condition is set based on the first pre-forward error correction padding factor. The first pre-forward error correction padding factor is determined based on the duration of the PE field and the nominal packet padding ability of the receiver.

[0021] In one implementation, the transmitter selects the duration of the PE field of the first PPDU based on the limit for the first hour. Further, the transmitter selects a second pre-forward error correction padding factor based on the selected duration of the PE field and the nominal packet padding ability of the receiver, and determines a first pre-forward error correction padding factor based on the second pre-forward error correction padding factor. The transmitter determines whether the LDPC additional symbol segment condition is satisfied based on the first pre-forward error correction padding factor, and sets the LDPC additional symbol segment field when the LDPC additional symbol segment condition is satisfied. In this implementation, the first PPDU End time The alignment between the first hour can be guaranteed. And the transmission of the PPDU in the scenario where PPDU alignment is required can be satisfied.

[0022] Referring to the first aspect, in some implementations of the first aspect, the EHT-SIG field of the first PPDU carries the LDPC additional symbol segment field, where the LDPC additional symbol segment field is set to be a second value, the EHT-SIG field carries the first pre-forward error correction padding factor, the second value indicates that no LDPC additional symbol segment needs to be added, the LDPC additional symbol segment field is set when the LDPC additional symbol segment condition is not satisfied, and the LDPC additional symbol segment condition is set based on the first pre-forward error correction padding factor. The first pre-forward error correction padding factor is determined based on the duration of the PE field and the nominal packet padding ability of the receiver.

[0023] In one implementation, the transmitter selects the duration of the PE field of the first PPDU based on the limit for the first time. Further, the transmitter selects a second pre-forward error correction padding factor based on the selected period of the PE field and the nominal packet padding ability of the receiver, and determines a first pre-forward error correction padding factor based on the second pre-forward error correction padding factor. The transmitter determines whether the LDPC additional symbol segment condition is satisfied based on the first pre-forward error correction padding factor, and sets the LDPC additional symbol segment field when the LDPC additional symbol segment condition is not satisfied. In this implementation, the first PPDU End time The alignment between the first PPDU and the first time can be guaranteed. And the transmission of the PPDU in scenarios where PPDU alignment is required can be satisfied.

[0024] In some of the foregoing implementations, the first pre-forward error correction padding factor is determined based on the second pre-forward error correction padding factor. The first PPDU is coded by using the first pre-forward error correction padding factor, and as a result, the duration that can be used by the receiver to re-decode the first PPDU is extended compared to the case where the first PPDU is coded by using the second pre-forward error correction padding factor.

[0025] Referring to the first aspect, in some implementations of the first aspect, the EHT-SIG field of the first PPDU carries the LDPC additional symbol segment field, where the LDPC additional symbol segment field is set to be a first value, the EHT-SIG field carries the second pre-forward error correction padding factor, the first value indicates that an LDPC additional symbol segment needs to be added, and the second pre-forward error correction padding factor is determined based on the duration of the PE field and the nominal packet padding ability of the receiver.

[0026] In this implementation, it is based on the first-hour limit. The transmitter selects the duration of the PE field, and then selects the second pre-forward error correction padding factor based on the selected duration of the PE field and the requirements for the nominal packet padding ability of the receiver. Based on this, the LDPC additional symbol segment condition is satisfied by default, and the transmitter sets the LDPC additional symbol segment field. Compared with another implementation where the transmitter needs to calculate whether the LDPC additional symbol segment condition is satisfied in order to further determine the pre-forward error correction padding factor, in this implementation, the procedure for selecting the pre-forward error correction padding factor is greatly simplified, and the computational complexity and the amount of calculation are reduced.

[0027] In addition, for example, in the aforementioned implementation, the first value may be "1", and the second value may be "0". It is obvious that the first value and the second value can be set to other values or characters in order to identify whether an LDPC additional symbol segment is added. This is not limited.

[0028] Referring to the first aspect, in some implementations of the first aspect, the first pre-forward error correction padding factor and the second pre-forward error correction padding factor satisfy the following formula.

Number

[0029] Referring to the first aspect, in some implementations of the first aspect, the duration of the PE field is increased by 4 microseconds, and the duration of the PE field is increased by 4 microseconds in the following cases. After the LDPC additional symbol segment condition is satisfied and the LDPC additional symbol segment is added, the requirement for the nominal packet padding ability of the receiver is not satisfied, the remaining duration is 4 microseconds or more, and the duration of the PE field does not reach the maximum allowable duration.

[0030] The LDPC additional symbol segment condition is set based on the second pre-forward error correction padding factor, and the second pre-forward error correction padding factor is determined based on the duration of the PE field obtained before 4 microseconds are added and the nominal packet padding ability of the receiver. And the remaining duration is determined based on the first duration, the duration of the preamble, the duration of the symbols in the data field, and the duration of the PE field obtained before 4 microseconds are added.

[0031] In this implementation, the transmitter pads the EHT-SIG field based on the limit for the first time and aligns the end time of the first PPDU with the first time. The duration of the PE field may be freely selected and is more flexible.

[0032] According to a second aspect, a communication device is provided. The communication device has the function of implementing this method according to any one of the first aspect or possible implementations of the first aspect. This function may be implemented by hardware or by hardware that executes the corresponding software. The hardware or software includes one or more units corresponding to the aforementioned functions.

[0033] According to a third aspect, a communication device including a processor and a memory is provided. Optionally, the communication device may further include a transceiver. The memory is configured to store a computer program. The processor is configured to call the computer program stored in the memory, execute it, and control the transceiver to transmit and receive signals. As a result, the communication device executes the present method according to the first aspect or any one of the possible implementations of the first aspect.

[0034] For example, the communication device is a transmitter for wireless communication.

[0035] According to a fourth aspect, a communication device including a processor and a communication interface is provided. The communication interface is configured to receive data and / or information and transmit the received data and / or information to the processor, and the processor processes the data and / or information. Then, the communication interface is further configured to output the data and / or information processed by the processor. As a result, the present method is executed according to the first aspect or any one of the possible implementations of the first aspect.

[0036] According to a fifth aspect, a computer-readable storage medium is provided. The computer-readable storage medium stores computer instructions, and when the computer instructions are executed on a computer, the present method is executed according to the first aspect or any one of the possible implementations of the first aspect.

[0037] According to a sixth aspect, a computer program product is provided. The computer program product includes computer program code, and when the computer program code is executed on a computer, the present method is executed according to the first aspect or any one of the possible implementations of the first aspect.

[0038] According to a seventh aspect, a chip is provided. The chip includes a processor, and a memory configured to store a computer program is disposed independently of the chip, and the processor is configured to execute the computer program stored in the memory. As a result, a device in which the chip is installed executes this method according to any one of the first aspect or possible implementations of the first aspect.

[0039] Optionally, the processor may be a processing circuit or a logic circuit.

[0040] Furthermore, the chip may include a communication interface. The communication interface may be an input / output interface, an interface circuit, etc. Furthermore, the chip may include a memory.

[0041] Optionally, there may be one or more processors and and one or more memories may exist.

[0042] According to an eighth aspect, a communication system is provided that includes a communication device (for example, a transmitter in this embodiment of the present application) according to any one of the second aspect to the fourth aspect, and one or more other communication devices that communicate with the communication device.

Brief Description of the Drawings

[0043]

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DETAILED DESCRIPTION OF THE INVENTION

[0044] The following describes the technical solutions according to the embodiments in the present application with reference to the accompanying drawings.

[0045] In the wireless local area network (WLAN) communication standard 802.11be, two types of extremely high throughput physical layer protocol data unit (EHT PPDU) formats are defined. That is, the extremely high throughput multiple user physical layer protocol data unit format (EHT MU PPDU), and the extremely high throughput trigger-based physical layer protocol data unit (EHT TB PPDU). The EHT MU PPDU can support single-user (downlink or uplink) and multi-user (downlink) data transmission. The EHT TB PPDU is a PPDU that is triggered to be transmitted by one or more stations (STAs) based on the scheduling information in the trigger frame transmitted by an access point (AP).

[0046] Figure 1 shows the EHT PPDU format according to this application. For the meaning, function, and duration of the fields in Figure 1, please refer to Table 1.

Table 1

[0047] In Table 1, * represents multiplication.

[0048] 1. Coding Procedure of EHT MU PPDU

[0049] Figure 2 shows the coding procedure of EHT MU PPDU according to this application. As shown in Figure 2, the media access control (MAC) layer of the transmitter determines the quantity of bytes transmitted by one or more users. The transmitter encodes the information bits of the corresponding quantity of bytes for each user in units of orthogonal frequency-division multiplexing (OFDM) symbols. The last symbol of the EHT PPDU needs to be executed for segment padding processing as shown in Figure 2.

[0050] It should be understood that Figure 2 shows the last symbol involved in coding. Not all subcarriers of the symbol are involved in coding, but only the bits of some segments may be involved in coding. In such an operation, the receiver can decode only some subcarriers during decoding, thereby saving processing time. The receiver does not need to process the bits related to another segment of the last symbol, and more processing time can be reserved for the receiver to process the bits that have not been processed before. In addition, a PE field may exist after the last symbol, and the PE field does not need to be processed by the receiver. More processing time can be reserved for the receiver.

[0051] The meaning of each piece of information in Figure 2 is as follows.

[0052] Excess information bits: Information bits included in the last symbol of the EHT PPDU.

[0053] Pre-forward error correction padding bits (pre-FEC padding bits): Padding bits involved in coding.

[0054] Post-FEC output bits: Output bits after scrambling and FEC.

[0055] Scrambling and FEC: Indicates scrambling and forward error correction, respectively.

[0056] Post-FEC padding bits: Indicates the amount of bits required by the total amount of encoding bits that need to be further padded to the symbol after coding. It should be understood that the total amount of bits is the amount of bits included in one symbol. Post-FEC padding bits are not involved in coding and do not need to be processed by the receiver.

[0057] N CBPS,Last,u : Indicates the amount of encoding bits of the last symbol.

[0058] N CBPS,u : (For symbols other than the last symbol) Indicates the amount of encoding bits of the symbol.

[0059] In addition, a indicates the capture position related to coding and may be referred to as the pre - FEC padding factor. There are a total of four capture positions, i.e., a = 1, 2, 3, and 4. For each, the output bits after FEC coding occupy approximately 1 / 4, 2 / 4, 3 / 4, and 1 of the entire symbol, and for each, it indicates that they correspond to one, two, three, and four segments of the last symbol respectively. That is, when a = 4, all sub - carriers are involved in coding.

[0060] Hereinafter, with reference to the procedure in FIG. 2, the coding procedure of the EHT PPDU will be described in detail.

[0061] (1) For the EHT MU PPDU, the transmitter first calculates, according to Equation (1), the amount of bits exceeding in the last data symbol for each user (e.g., the u - th user), i.e., the excess information bits.

Equation

[0062] In Equation (1), N excess,u represents the amount of excess information bits present in the last data symbol of the u - th user.

[0063] APEP_LENGTH u represents the amount of pre - end of frame padding of the aggregated - medium access control data unit (A - MPDU) frame of the u - th user, and can be understood as the amount of useful information bits in bytes transmitted at the MAC layer.

[0064] N tailrepresents the coded tail bit, and for binary convolutional coding (BCC), the value is 6, and for low-density parity-check (LDPC), the value is 0.

[0065] N service is the number of bits in the service field, and the value is 16.

[0066] N DBPS,u is the amount of bits included in each symbol of the u-th user.

[0067] (2) The transmitter calculates the number of initial segments of the last OFDM symbol and the number of initial OFDM symbols according to N excess,u , Equation (2), and Equation (3). [Number] [Number] N DBPS,short,u = N CBPS,short,u ·R u , and R u is the bit rate of the u-th user. N CBPS,short,u = N SD,short,u ·N SS,u ·N BPSCS,u is.

[0068] N SD,short,u is the number of information bits carried in the segment within the last symbol, predefined in the communication protocol standard for the corresponding resource unit (RU) or multiple resource units (MRU), N SS,u is the number of spatial streams of the u-th user, and N BPSCS,uis the amount of encoded bits in each sub - carrier of each spatial stream of the u - th user.

[0069] (3) The transmitter determines the number of users (hereinafter referred to as u max as shown) having the largest amount of encoded bits among all users according to the following formula.

Number

Number

[0070] (4) The transmitter determines the amount of the initial segment and the amount of the initial OFDM symbol of u max as the amount of the common initial segment and the amount of the initial OFDM symbol of all users.

Number

Number

[0071] (5) The transmitter calculates the amount of the initial data bits and the amount of the initially encoded bits of the last OFDM symbol of each user according to the following formula.

Number

Number

[0072] For each user using LDPC coding, the pre - forward error correction padding bits of the u - th user can be calculated according to the following formula.

Number

[0073] For each user using LDPC coding, the load bit N that can be transmitted by the u-th user pld,u and the number of bits N avbits,u are calculated based on the following equations (6) and (7), respectively.

Equation

Equation

[0074] The transmitter, based on N pld,u and N avbits,u calculates the code length L of the LDPC code word LDPC,u , and the number of code words N avbits,u of N CW,u is calculated according to a table or equation pre-determined in the communication standard.

[0075] Next, the transmitter calculates the number of shortening bits N shrt,u of the u-th user, and the number of bits N punc,u that need to be punctured for the u-th user.

Equation

Equation

[0076] For users using LDPC coding, when at least one user satisfies the condition of the following equation (8), the transmitter needs to set the LDPC additional symbol segment field in the EHT-SIG field to 1.

Equation

[0077] In this embodiment of the present application, the condition in Equation (8) is hereinafter referred to as the LDPC additional symbol segment condition.

[0078] In addition, for all users using LDPC coding, using the following equations (9) and (10), N avbits,u is added, and N punc,u is recalculated. Specifically, when at least one user satisfies the condition of Equation (8), all users using LDPC coding need to update N avbits,u and N punc,u .

Number

Number

[0079] Furthermore, the transmitter updates the pre-FEC padding factor a and N SYM according to the following equations.

Number

[0080] In the whole of the above equations, if the first (initial) captured position is 4, it can be understood that it indicates that it is already at the maximum quantity of the segments of the last symbol. If another segment needs to be added, the symbol needs to be added first (first), and then the first capture position is selected from the added symbols. That is, the capture position a = 1.

[0081] If the user using LDPC coding does not satisfy the condition of the LDPC additional symbol segment condition, or if all users use BCC coding, the LDPC additional symbol segment field in the EHT-SIG field is 0, N SYM = N SYM.int , and, a = a init It needs to be set as such.

[0082] That is, when the LDPC additional symbol segment condition is not satisfied, the pre-FEC padding factors a and N SYM are not updated. Therefore, the pre-FEC padding factor a is the quantity of the initial segment, and N SYM is also the quantity of the initial symbol.

[0083] In addition, for users using LDPC coding, it is as follows.

Number

Number

[0084] For users using BCC coding, it is as follows.

Number

[0085] In addition, for any user, regardless of whether LDPC coding or BCC coding is used, the N of the last symbol CBPS,last,u is calculated as follows.

Number

[0086] In addition, for users using BCC coding, the quantity of pre-FEC padding bits (i.e., pre-forward error correction padding bits) is calculated according to the following formula.

Number

[0087] For any user, regardless of whether LDPC coding or BCC coding is used, the number of post-FEC padding bits (i.e., post-forward error correction padding bits) of the last symbol is calculated according to the following formula.

Number

[0088] Furthermore, pre-FEC padding is classified into MAC padding and PHY padding, and the number of bits is as follows respectively.

Number

Number

[0089] In addition, the receiver further requests from the transmitter the capabilities that the receiver needs for additional processing time. This capability is referred to in this specification as the nominal packet padding capability. This is not limited in this specification. The selection of the duration of each field of the PPDU transmitted by the transmitter to the receiver needs to satisfy the receiver's nominal packet padding capability, where the condition is that the sum of the duration of the post-forward error correction padding part (i.e., the duration of the post-FEC padding bits, see Figure 2) and the duration of the PE field is greater than or equal to all the nominal packet padding capabilities required by the receiver.

[0090] 2. Coding Procedure of EHT TB PPDU

[0091] Figure 3 shows the coding procedure of an EHT TB PPDU according to the present application. As shown in Figure 3, one example where an AP transmits a trigger frame to schedule an EHT TB PPDU is used for illustration. First, the AP transmits a trigger frame to schedule one or more STAs to transmit an EHT TB PPDU. In the trigger frame, the AP indicates the uplink length, the guard interval, the type of the EHT-LTF field, the number of symbols in the EHT-LTF field, the pre-FEC padding factor, the LDPC additional symbol segment field, and the packet extension disambiguity (PE Disambiguity) field. It should be noted that the trigger frame is a MAC frame, also called a MAC protocol data unit (MPDU), and is carried in the data field or carried in a physical service data unit (PSDU) or PPDU. Management area access control protocol data unit

[0092] When the transmitter calculates that at least one user satisfies the LDPC additional symbol segment condition by using the aforementioned coding procedure of the EHT MU PPDU, the transmitter sets the LDPC additional symbol segment field in the trigger frame to 1. Different from the coding procedure of the EHT MU PPDU, even when the LDPC additional symbol segment condition is not satisfied, the AP can set the LDPC additional symbol segment field to 1. However, in the coding procedure of the EHT MU PPDU, when the LDPC additional symbol segment condition is not satisfied, the transmitter needs to set the LDPC additional symbol segment field to 0.

[0093] After receiving the trigger frame, the STA calculates the length T of the PE field and the number N of OFDM symbols in the data field based on the parameters and information indicated in the trigger frame. PE and the number N SYM of OFDM symbols in the data field.

[0094] Specifically, the STA can calculate T PE and N SYM separately according to equations (11) and (12).

Number

Number

[0095] In equation (12),

Number

[0096] The trigger frame includes a coding indication field for each STA to indicate to the STA to use BCC or LDPC. However, when the number of subcarriers of the RU or MRU assigned to a specific STA is 242 or more, the STA fixedly uses LDPC and does not need to be indicated.

[0097] For the STA, when BCC coding is used, the coding procedure is the same as the coding procedure for the EHT MU PPDU, where NSYM,init =N SYM 、a init =a, and a is a pre-FEC padding factor and is indicated by the trigger frame.

[0098] When LDPC coding is used, in one case, the LDPC additional symbol segment field is set to 1, and the STA calculates a based on a indicated in the trigger frame. init to calculate.

[0099] Specifically, the STA performs the calculation according to the following formula.

Equation

[0100] Through the calculation of a init and N SYM,init After obtaining, the STA updates N according to the aforementioned formulas (9) and (10), and then performs coding by using the subsequent coding procedure of the EHT MU PPDU. avbits,u and N punc,u and then performs coding by using the subsequent coding procedure of the EHT MU PPDU.

[0101] When LDPC coding is used, in other cases, the LDPC additional symbol segment field is set to 0, and N SYM,init =N SYM , and a init =a. In other words, N avbits,u and N punc,u do not need to be updated, and the STA can directly perform coding by using the subsequent coding procedure of the EHT MU PPDU.

[0102] The above describes the coding procedures for EHT MU PPDU and EHT TB PPDU in this application. It includes the selection of the pre-FEC padding factor, the determination of the LDPC additional symbol segment conditions, and the setting of the LDPC additional symbol segment fields.

[0103] The technical solution provided in this application is applicable to the WLAN scenario. By way of example, it is applicable to the standards of the IEEE802.11 system, such as 802.11a / b / g, 802.11n, 802.11ac, 802.11ax, or the next-generation 802.11ax, such as 802.11be, or even further next-generation standards.

[0104] Embodiments of this application are mainly described by using an example where a WLAN network, particularly a network to which the IEEE802.11 system standard is applied, is deployed. However, those skilled in the art can easily understand that the aspects involved in this application can be extended to other networks that adopt various standards or protocols, such as high-performance radio local area network (HIPERLAN), wide area network (WAN), personal area network (PAN), or any other network known or developed in the future. HIPERLAN is a wireless standard similar to IEEE802.11 and is mainly used in Europe. Therefore, the various aspects provided in this application are applicable to any suitable wireless network regardless of the coverage and wireless access protocol.

[0105] Embodiments of the present application may be further applicable to wireless local area network systems such as the internet of things (IoT) network or the vehicle to X (V2X) network. Certainly, embodiments of the present application may be further applicable to other possible communication systems, such as the long term evolution (LTE) system, the LTE frequency division duplex (FDD) system, the LTE time division duplex (TDD) system, the universal mobile telecommunication system (UMTS), the worldwide interoperability for microwave access (WiMAX) communication system, the fifth generation (5 th generation, 5G) communication system, and the future sixth generation (6 th generation, 6G) communication system.

[0106] The aforementioned communication systems used in the present application are merely examples for illustration and are not limited thereto. In this specification, a unified description is provided and the details will not be described again below.

[0107] Figure 4 is a schematic diagram of a communication system according to the present application. As shown in Figure 4, the method for transmitting the PPDU provided in the present application is applicable to data communication between one or more APs and one or more STAs (for example, data communication between AP1 and STAs1 and STA2), data communication between APs (for example, data communication between AP1 and AP2), and data communication between STAs (for example, data communication between STA2 and STA3).

[0108] An access point may be an access point for a terminal device (e.g., a mobile phone) to access a wired (or wireless) network, and is mainly arranged in a home, or a building or zone. The typical coverage radius is from dozens of meters to hundreds of meters. Certainly, the access point may also be arranged outdoors. The access point corresponds to a bridge that connects a wired network and a wireless network. The main function of the access point is to connect various wireless network clients together and then connect the wireless network to Ethernet (registered trademark). Specifically, the access point may be a terminal device (e.g., a mobile phone) or a network device (e.g., a router) having a Wi-Fi chip. The access point may be a device that supports the 802.11be standard. The access point may also be a device that supports multiple wireless local area network (WLAN) standards of the 802.11 family, such as 802.11ax, 802.11ac, 802.11n, 802.11g, 802.11b, 802.11a, and the next-generation 802.11be. The access point in this application may be a high-efficiency (HE) AP, or an extremely high throughput (EHT) AP, or an access point applicable to future-generation Wi-Fi standards.

[0109] A station may be, for example, a wireless communication chip, a wireless sensor, a wireless communication terminal, etc., and may also be referred to as a user. For example, the station may be a mobile phone, a tablet computer, a set-top box, a smart TV, a smart wearable device, an in-vehicle communication device, a computer, etc. that support Wi-Fi communication functions. Optionally, the station may support the 802.11be standard. The station may also support multiple wireless local area network (WLAN) standards of the 802.11 family, such as 802.11ax, 802.11ac, 802.11n, 802.11g, 802.11b, 802.11a, and the next-generation 802.11be.

[0110] In this application STA may be a high-efficiency (HE) STA or an extremely high throughput (EHT) STA, or may be an STA applicable to future generations of Wi-Fi standards.

[0111] For example, the access point and the station may be devices used inside a vehicle, nodes used in the Internet of Things (IoT), sensors, etc., smart cameras, smart remote controls, smart water or electricity meters, etc. in a smart home, sensors, etc. in a smart city.

[0112] Embodiments of the present application provide a communication method applicable to a wireless local area network system. This method can be implemented by a communication device within a wireless local area network system, or by a chip or a processor within the communication device. The communication device may be a wireless communication device that supports multi-link parallel transmission, such as a multi-link device or a multi-band device. Compared with a device that only supports single-link transmission, a multi-link device has higher transmission efficiency and higher throughput.

[0113] FIG. 21 is a schematic diagram of communication between multi-link devices according to the present application.

[0114] As shown in FIG. 21, a multi-link device includes one or more affiliated STAs, and an affiliated STA is a logical station and can operate on one link. The affiliated station may be an access point (AP) or a non-access point station (non-APSTA). For ease of explanation, in the present application, a multi-link device whose affiliated station is an AP may be referred to as a multi-link AP, a multi-link AP device, or an AP multi-link device. A multi-link device whose affiliated station is a non-APSTA may be referred to as a multi-link STA, a multi-link STA device, or an STA multi-link device. For ease of explanation, "a multi-link device includes an affiliated STA" may also be briefly described as "a multi-link device includes an STA" in the embodiments of the present application.

[0115] The multi-link device includes a plurality of logical stations, and it should be noted that each logical station operates on a single link, but the plurality of logical stations can operate on the same link. The link identifiers described below represent one station operating on one link. In other words, if there are two or more stations on one link, two or more link identifiers are used to represent the two or more stations. The links mentioned below sometimes also represent the stations operating on the links.

[0116] In this application, the transmitter mentioned below may be a multi-link device (e.g., the first multi-link device in FIG. 21), and the receiver may alternatively be a multi-link device (e.g., the second multi-link device in FIG. 21). In addition, either the transmitter or the receiver may be a multi-link device. This is not limited.

[0117] Below, solutions for implementing EHT PPDU alignment for EHT PPDU in two different formats, namely EHT MU PPDU and EHT TB PPDU, will also be described separately.

[0118] 1. EHT MU PPDU Alignment

[0119] FIG. 5 is a schematic flowchart of a method for transmitting a PPDU according to this application.

[0120] 210: The transmitter controls the duration of one or more fields among the PE field, EHT-SIG field, and EHT-LTF field of the first PPDU, and / or delays the transmission time of the first PPDU, so that the error between the end time of the first PPDU and the first time does not exceed the error threshold.

[0121] 220: The transmitter transmits the first PPDU.

[0122] The receiver receives the first PPDU.

[0123] In the technical solution provided in the present application, the transmitter controls the duration of one or more of the PE field, EHT-SIG field, and EHT-LTF field of the first PPDU, thereby End time performing alignment between the first PPDU and the first time, and / or delaying the transmission time of the first PPDU.

[0124] Optionally, the first time may be the end time of a PPDU (for example, the second PPDU) on a link different from the link where the first PPDU is located, or may be a specific time determined by the transmitter. This is not limited.

[0125] It should be particularly noted that "alignment" in the present application does not strictly mean perfect alignment, and alignment is performed on the condition that the time interval between the end time of the first PPDU and the first time is less than the error threshold. Therefore, the end time of the first PPDU may be before or after the first time, or may overlap with the first time. For example, the error threshold can be set according to the requirements in the alignment scenario. For example, the error threshold is 8 microseconds, 4 microseconds, etc.

[0126] In the following, several different implementations of PPDU alignment by using different fields in the present application will be described.

[0127] (1) PE field

[0128] Solution 1

[0129] In Solution 1, the first PPDU includes a preamble, a data field, and a PE field. The duration of the PE field is determined based on the first duration, the duration of the preamble, and the duration of the symbols in the data field. The first duration is the duration between the first time and the start time of the first PPDU.

[0130] The duration of the symbols in the data field is the length of one symbol in the data field.

[0131] It should be noted that the "symbol" in this application is an OFDM symbol. The lengths of the symbols in different fields of the first PPDU can be different. For example, the length of the symbols in the data field can be different from the duration of the symbols in another field included in the preamble. Therefore, the symbols in the data field and the symbols in the EHT-LTF field specifically refer to the respective symbols in these fields.

[0132] Referring to Figure 6, hereinafter, how the transmitter implements the alignment between the first PPDU End time and the first time by controlling the duration of the PE field will be described in detail.

[0133] Figure 6 is a flowchart related to generating and transmitting the first PPDU by a transmitter according to this application.

[0134] 301: Based on the first duration, the transmitter calculates the number of symbols (hereinafter denoted as N SYM as shown) in the data field of the first PPDU and the duration of the PE field (hereinafter denoted as T PE as shown).

[0135] The first duration is the expected (or target) duration for the transmitter to transmit the first PPDU.

[0136] For example, the transmitter calculates the available duration for transmitting the first PPDU on the current link by using the end time of a PPDU on another link as a reference point. For another example, the transmitter predicts that the first PPDU will end at a specific time (e.g., the first time), and calculates the available duration for transmitting the first PPDU, i.e., the first duration, by using that time as a reference point. It should be understood that for the "available duration for sending the first PPDU", the duration for transmitting the first PPDU is limited by the first time so as to perform an alignment between the end time of the first PPDU and the first time. In other words, the first time is used as a reference point, and the transmitter transmits the first PPDU by using the remaining duration from the start time of the first PPDU to the first time to perform an alignment between the end time of the first PPDU and the first time.

[0137] FIG. 7 shows an example related to determining the first duration according to the present application. As shown in FIG. 7, the transmitter transmits PPDU2 on link 2. The transmitter obtains an opportunity to transmit on link 1 by contending for the channel. It is assumed that the transmitter transmits PPDU1 on link 1. It is assumed that the error threshold between the end time of PPDU1 and the end time of PPDU2 is 8 microseconds. The transmitter calculates the duration between the start time of PPDU1 and the end time of PPDU2, and the duration is the first duration in the present application.

[0138] The transmitter calculates the number N of symbols in the data field according to the following formula (13). SYM to calculate.

Number

[0139] After obtaining N through calculation SYM the transmitter calculates the remaining duration according to Equation (14).

Equation

[0140] The transmitter sets the duration of the PE field to the remaining duration, so that the alignment of the first PPDU can be performed.

[0141] For example, the duration of the PE field can be determined according to the following Equation (15).

Equation

[0142] Since the duration of the PE field is a multiple of 4 microseconds, it should be understood that Equation (15) is designed in this way.

[0143] In addition, the PE non-ambiguity field is set to 0 based on T PE obtained according to the above equation.

[0144] Optionally, TPE When it is equal to 0 or 4 microseconds, the transmitter may further select to reduce one OFDM symbol in order to obtain a larger T PE As a result, the receiver obtains more processing duration. Specifically, based on N SYM calculated according to Equation (13), the transmitter sets N SYM = N SYM -1. In this case, the transmitter needs to set the PE non-ambiguity field to 1, so that the receiver can remove the ambiguity of the length of the PE field. [Number]

[0145] In this case, the first duration can be determined according to the following formula. [Number]

[0146] In addition, the transmitter needs to further select the coding method, modulation and coding method, spatial stream, etc. for each user (i.e., receiver). For details, refer to the aforementioned coding procedure of the EHT MU PPDU. Details are not described again in this specification.

[0147] 302: The transmitter selects the second pre-forward error correction padding factor and the nominal packet padding ability value of the receiver based on T PE .

[0148] For the sake of clarity and conciseness of the description, the second pre-forward error correction padding factor is represented as a2 below.

[0149] The nominal packet padding ability value of the receiver is used to indicate the nominal packet padding ability of the receiver, and the nominal packet padding ability value can be provided by the receiver to the transmitter.

[0150] 303: The transmitter, based on a init = a2, calculates N pld,u and N avbits,u and performs coding.

[0151] a init is the quantity of the above-mentioned initial segments, and it should be understood that a init = a2 indicates that the transmitter uses a2 as the quantity of the initial segments. From the above-mentioned coding procedure of the EHT MU PPDU, after determining the quantity of the initial segments (i.e., a init ) and the quantity of the initial symbols in the data field (i.e., N SYM,init ), the receiver can obtain the receiver's N pld,u and N avbits,u through calculation, and it can be seen that coding can be performed based on N pld,u and N avbits,u .

[0152] 304: The transmitter determines whether the LDPC additional symbol segment condition is satisfied.

[0153] Specifically, after obtaining N pld,u and N avbits,u through calculation, the transmitter performs EHT MU PPDU coding. Through coding, the transmitter can know the quantity N shrt,u of the shortened bits and the quantity N punc,u of the punctured bits. Furthermore, based on N shrt,u and N punc,u , the transmitter determines whether the LDPC additional symbol segment condition is satisfied.

[0154] For the description of the LDPC additional symbol segment condition, refer to the above description. Details are not described again in this specification.

[0155] If the LDPC additional symbol segment condition is not satisfied, the transmitter executes step 307.

[0156] If the LDPC additional symbol segment condition is satisfied, the transmitter executes step 305.

[0157] It should be noted that steps 303 and 304 are optional steps, as shown in the dashed box of FIG. 6. In other words, after selecting a2 in step 302, the transmitter may directly execute step 305.

[0158] 305: The transmitter is a init = a1, based on N pld,u and N avbits,u to calculate, and perform coding.

[0159] In the above, a1 is referred to as the first pre-forward error correction padding factor in this specification, and a1 is determined according to a2.

[0160] Specifically, the transmitter determines a1 according to the following formula (16), and sets a init to a1.

Equation

[0161] Furthermore, the transmitter is a init = a1 and N SYM,init based on, N pld,u and N avbits,u to calculate, and N pld,u and N avbits,u to perform EHT MU PPDU coding by using. After coding, N shrt,u and N punc,u are obtained. Therefore, based on N shrt,u and N punc,u it can be determined whether the LDPC additional symbol segment condition is satisfied.

[0162] In the case other than a2 = 1 in formula (16), specifically, it should be understood that a2 = 2, a2 = 3, or a2 = 4.

[0163] When the transmitter executes step 303 and step 304 after step 302 and executes step 305 based on the determination result in step 304, in step 305, the transmitter sets a init to a1, that is, the transmitter updates a init from a2 to a1. It should be noted that N SYM,init also needs to be redetermined according to formula (16). Then, the transmitter updates N init = a1 and the redetermined N SYM,init based on a1 and the redetermined N pld,u and N avbits,u . Further, N shrt,u and N punc,u are updated based on the updated N pld,u and N avbits,u , and based on the updated N shrt,u and N punc,u , it is determined whether the LDPC additional symbol segment condition is satisfied.

[0164] 306: The transmitter determines whether the LDPC additional symbol segment condition is satisfied.

[0165] It should be particularly noted that the LDPC additional symbol segment condition is related to a init . After a init is updated, the setting parameters of the LDPC additional symbol segment condition change. Specifically, it should be considered that it changes from a2 to a1.

[0166] In other words, in both step 304 and step 306, it is determined whether the LDPC additional symbol segment condition is satisfied. However, the LDPC additional symbol segment condition in step 304 is a initis set based on a2, that is, it is set based on a2. However, in step 306, a init is updated to 1. Therefore, the LDPC additional symbol segment condition in step 306 is that a init is set based on a1, that is, it is set based on a1.

[0167] In addition, from Equation (16), it can be seen that in addition to a init the LDPC additional symbol segment condition is also related to N SYM,init However, the update of a init does not necessarily cause the update of N SYM,init In Equation (16), N SYM is within the data field of the first PPDU and is the amount of symbols obtained through calculations based on the first time, and it should be understood that it is obtained through calculations according to Equation (13). In addition, N SYM,init is the quantity of symbols within the data field set in the LDPC additional symbol segment condition.

[0168] 307: The transmitter generates the first PPDU.

[0169] Specifically, the transmitter sets the LDPC additional symbol segment field of the first PPDU based on the determination result of whether the LDPC additional symbol segment condition is satisfied.

[0170] As described in step 304 above, when the transmitter determines that the LDPC additional symbol segment condition is not satisfied, the transmitter directly executes step 307. In this case, the transmitter sets the LDPC additional symbol segment field to a second value, and the second value indicates that there is no need to add an LDPC additional symbol segment, and the LDPC additional symbol segment field carries a2.

[0171] When setting the LDPC additional symbol segment field based on the determination result in step 306, the transmitter sets the LDPC additional symbol segment field according to the following principle.

[0172] When the LDPC additional symbol segment condition is satisfied, the transmitter sets the LDPC additional symbol segment field to a first value, and the LDPC additional symbol segment field carries a2. For example, the first value may be "1".

[0173] When the LDPC additional symbol segment condition is not satisfied, the transmitter sets the LDPC additional symbol segment field to a second value, and the LDPC additional symbol segment field carries a1. For example, the second value may be "0".

[0174] After the transmitter determines the duration of the PE field and sets the LDPC additional symbol segment field, this is equivalent to the transmitter determining the fields of the first PPDU. Based on this, the transmitter generates the first PPDU.

[0175] 308: The transmitter transmits the first PPDU.

[0176] The procedure in FIG. 7 is only intended to facilitate the understanding of the solution of the present application, and it should be understood that the process by which the transmitter generates the first PPDU is divided into different steps. In fact, in the present application, the process by which the transmitter generates the first PPDU is a process in which the transmitter determines the duration of each field and sets the fields of each field. Therefore, these steps may also be combined into fewer steps, or divided into more steps, which should not constitute any limitation to the solution itself. The same is true for other procedures in the present application, and the details will not be described again below.

[0177] In Solution 1, the transmitter calculates the duration of the PE field of the first PPDU based on the limit of the first hour. As a result, when the nominal packet padding ability of the receiver is satisfied, the first PPDU End time and the first hour are guaranteed to be consistent.

[0178] The following provides an example related to Solution 1 with reference to FIG. 8.

[0179] FIG. 8 is a schematic diagram related to the selection of a pre-forward error correction padding factor by a transmitter according to the present application.

[0180] As shown in FIG. 8, the nominal packet padding ability value claimed by the receiver is 20 microseconds, and it is assumed that the transmitter selects the duration of the PE field to be 8 microseconds. Further, based on steps 301 and 302 shown in FIG. 7, the transmitter selects a2 = 3. The duration of the segment is 4 microseconds, and since the bits in data segment 4 and the PE field do not need to be processed by the receiver, the 12 microseconds required by the receiver's nominal packet padding ability can be satisfied. In another implementation, the transmitter can alternatively determine a1 based on a2. Here, a1 = 3 - 1 = 2. That is, the transmitter adds data segment 3. In this case, data segment 3 and data segment 4 do not need to be processed by the receiver. The total duration of data segment 3, data segment 4, and the PE field is 4 + 4 + 8 = 16 microseconds. Comparing with the 12 microseconds required by the receiver, there are an additional 4 microseconds, and it can be seen that the receiver obtains more processing time.

[0181] In the procedure of FIG. 6, after the transmitter selects a2, in one implementation, the transmitter is a initBased on =a2, it is determined whether the LDPC additional symbol segment condition is satisfied. If the LDPC additional symbol segment condition is satisfied, the transmitter is a init Based on =a1, it is determined whether the LDPC additional symbol segment condition is satisfied, and then, based on the determination result, the LDPC additional symbol segment field is set. In this implementation, it can be seen that the transmitter determines whether the LDPC additional symbol segment condition is satisfied twice. The process of selecting the pre-forward error correction padding factor by the transmitter is complex, and the computational complexity is excessively large.

[0182] In another implementation, after selecting a2, the transmitter directly selects a1 based on a2, and a init Based on =a1, it is determined that the LDPC additional symbol segment condition is satisfied, and then, based on the determination result, the LDPC additional symbol segment field is set. Compared with the previous implementation, in the latter implementation, the process of determining whether the LDPC additional symbol segment condition is satisfied based on =a2 is omitted. That is, the number of times of determining the LDPC additional symbol segment condition is reduced by one, so the calculation process of the transmitter is simplified. However, after selecting a1, the transmitter still needs to calculate whether the LDPC additional symbol segment condition is satisfied, and the computational complexity is still relatively large. init In view of this, Solution 2 is provided below. Compared with any implementation in Solution 1, in Solution 2, the complexity of selecting the pre-forward error correction padding factor is simplified, and the computational complexity in the selection process is also reduced.

[0183]

[0184] Solution 2

[0185] FIG. 9 is another flowchart related to generating and transmitting a first PPDU by a transmitter according to the present application.

[0186] 401: The transmitter calculates N SYM and T PE based on the first duration.

[0187] 402: Select a2 based on the nominal packet padding capability values of TPE and the receiver.

[0188] 403: The transmitter calculates N init and N pld,u and N avbits,u based on a

[0189] = a1 and performs coding. Herein, a1 is determined according to a2.

[0190] For example, the transmitter determines a1 according to the following formula and a2.

Equation

[0191] It can be seen that this formula is the aforementioned formula (16). Details will not be described again.

[0192] 404: The transmitter generates a first PPDU.

[0193] In step 404, the transmitter generating the first PPDU mainly includes the transmitter setting the LDPC additional symbol segment field of the first PPDU. Specifically, the transmitter directly sets the LDPC additional symbol segment field to 1, and the LDPC additional symbol segment field carries 2.

[0194] 405: The transmitter transmits the first PPDU.

[0195] In Solution 2, after selecting a2, the transmitter by default considers that the LDPC additional symbol segment condition is satisfied, directly calculates a1 based on a2, and then calculates a based on a1. init Based on a=a1, coding is performed. After the coding is completed, the LDPC additional symbol segment field is directly set to 1. In other words, the LDPC additional symbol segment needs to be added by default, and a2 is carried in the LDPC additional symbol segment field.

[0196] In Solution 2, the transmitter does not need to calculate whether the LDPC additional symbol segment condition is satisfied. As a result, it can be seen that the process of selecting the pre-forward error correction padding factor is greatly simplified, and the computational complexity and the amount of calculation are reduced.

[0197] The following provides an example of the solution with reference to FIG. 10. 2 of the solution.

[0198] FIG. 10 is another schematic diagram related to the selection of the pre-forward error correction padding factor by a transmitter according to the present application.

[0199] As shown in FIG. 10, the transmitter selects a2 = 4 based on steps 401 and 402 in FIG. 9. Based on this, the transmitter directly determines a1 based on a2. Here, a1 = a2 - 1 = 3, that is, data segment 3 is directly added. In this case, data segment 3 and data segment 4 do not need to be processed by the receiver. The total duration of data segment 3, data segment 4, and the PE field can satisfy the nominal packet padding ability of the receiver, or can enable the receiver to obtain more processing time.

[0200] The above describes a solution in which PPDU alignment is implemented by controlling the duration of the PE field.

[0201] In a solution where PPDU alignment is implemented by using the duration of the PE field, since there are strict alignment requirements, it can be seen that the transmitter cannot randomly select the length of the MAC frame to be transmitted and the length of the PE field. The transmitter needs to adjust the length of the PE field (with a granularity of 4 microseconds) based on the target time (i.e., the first time) in order to implement the alignment of the end time of the PPDU. In this application, the length of the OFDM symbol in the data field of the EHT PPDU is one of 13.6 microseconds, 14.4 microseconds, or 16 microseconds, and the granularity is considered to be relatively large. As a result, the PPDU alignment requirements cannot be satisfied by using the symbols in the data field. However, the length granularity of the PE field is a multiple of 4 microseconds, and the PPDU alignment requirements using an error threshold of 4 microseconds or 8 microseconds can be satisfied.

[0202] The following describes a solution in which PPDU alignment is implemented by controlling the duration of the EHT-SIG field.

[0203] (2) EHT-SIG field

[0204] Solution 3

[0205] In Solution 3, the first PPDU includes a preamble, a data field, and a PE field. The preamble includes an EHT-SIG field, and the EHT-SIG field includes an initial part and a padding part. The duration of the padding part in the EHT-SIG field is determined based on a first duration, an initial duration of the preamble, a duration of the PE field, and a duration of symbols in the data field. The initial duration of the preamble does not include the duration of the padding part in the EHT-SIG field, and the first duration is the duration between a first time and a start time of the first PPDU. The duration of the padding part is a multiple of 4 microseconds.

[0206] The following describes Solution 3 with reference to FIG. 11.

[0207] FIG. 11 is another flowchart related to generating and transmitting a first PPDU by a transmitter according to the present application.

[0208] 501: The transmitter selects a duration T of the PE field PE and calculates N SYM .

[0209] Optionally, in one embodiment, the transmitter always selects the maximum duration of the PE field allowed in the communication standard.

[0210] For example, when at least one user uses at least eight spatial streams, or when a resource unit (RU) of 2×996 or more subcarriers or multiple resource units (MRUs) are allocated, or when a 4096 quadrature amplitude modulation (QAM) scheme is used, the transmitter selects a 20-microsecond PE field, or in another case, may select a 16-microsecond PE field. Thus, the transmitter determines TPE The advantage of selecting this is that the requirements for the nominal data padding capabilities of all receivers can be reliably met.

[0211] In another embodiment, the transmitter may alternatively select the shortest duration from the durations of the PE fields that can satisfy the requirements for the nominal packet padding capabilities of the receivers.

[0212] The duration T of the PE field PE After the duration T is selected, the amount of symbols NSYM in the data field of the first PPDU is calculated according to the following formula (17).

Number

[0213] In a solution where PPDU alignment is performed by using the duration of the EHT-SIG field, it should be noted that the initial duration of the preamble of the first PPDU is used. The initial duration is the duration of the preamble of the first PPDU before the padding part of the EHT-SIG field is added. After the padding part of the EHT-SIG field is added, the preamble includes the initial part and the padding part of the EHT-SIG field. Therefore, the duration of the preamble is increased by only the duration of the padding part of the EHT-SIG field based on the initial duration of the preamble. The initial part of the EHT-SIG field is sufficient to carry the necessary signaling instruction information. The following details the padding part of the EHT-SIG field.

[0214] The transmitter calculates the remaining duration according to the following formula (18).

Number

[0215] In this solution, it should be understood that the padding part of the EHT-SIG field is determined based on the remaining duration. Therefore, the remaining duration is expressed as follows. T additional_EHT_SIG_est

[0216] FIG. 12 shows an EHT PPDU obtained before the EHT-SIG field is padded according to the present application. It should be noted that the duration of the preamble in FIG. 12 is the initial duration of the preamble.

[0217] 502: The transmitter is T PE and based on the nominal packet padding capability value of the receiver, selects the second pre-forward error correction padding factor a2.

[0218] In step 502, when the duration of the PE field selected in step 501 already meets the requirements regarding the nominal packet padding ability of the receiver, a2 may be freely selected. That is, the duration of the PE field guarantees that the receiver has sufficient processing time, and the transmitter can select a2 without being affected by the nominal packet padding ability of the receiver.

[0219] 503: The transmitter calculates N pld,u and N avbits,u based on a init =a2 and performs coding.

[0220] 504: The transmitter determines whether the LDPC additional symbol segment condition is satisfied.

[0221] If the LDPC additional symbol segment condition is not satisfied, the transmitter executes step 507.

[0222] If the LDPC additional symbol segment condition is satisfied, two implementations are provided and are shown below as Implementation 1 and Implementation 2.

[0223] Implementation 1

[0224] First, the transmitter updates N SYM and the pre-forward error correction padding factor a according to the following formula (19).

Equation

[0225] The transmitter uses the updated N SYMBased on b and a, it is determined whether the requirements for the nominal packet padding ability of the receiver are met. If the requirements are not met, the remaining duration is 4 microseconds or more, and the duration of the PE field does not reach the maximum length allowed in the communication standard, the duration of the PE field is extended by 4 microseconds to meet the requirements regarding the nominal packet padding ability of the receiver.

[0226] Therefore, TPE satisfies the following formula (20).

Equation

[0227] Since the duration of the PE field is increased by 4 microseconds, the remaining duration is decreased by 4 microseconds. That is, T additional_EHT_SIG_est satisfies formula (21).

Equation

[0228] That is, in Implementation 1, the duration of the PE field of the first PPDU finally generated by the transmitter is increased by 4 microseconds added to the selected duration TPE of the PE field in step 501.

[0229] Implementation 2

[0230] In Implementation 2, the transmitter executes step 505.

[0231] It should be noted that steps 503 and 504 are optional selection steps as shown in the dashed box in FIG. 11. In other words, in step 502, after selecting a2, the transmitter directly executes step 505, that is, a init can be determined as = a1. Here, a1 is determined based on a2.

[0232] 505: The transmitter calculates N init and N pld,u based on a avbits,u = a1, and then executes coding.

[0233] In the above, a1 is determined according to a2. For details, refer to the aforementioned formula (16).

Equation

[0234] The transmitter calculates N init and N pld,u based on a avbits,u = a1, and then executes EHT MU PPDU coding based on N pld,u and N avbits,u . After coding, N shrt,u and N punc,u are obtained. In this way, the transmitter determines whether the LDPC additional symbol segment condition is satisfied based on N shrt,u and N punc,u .

[0235] If the transmitter executes step 503 and step 504 after step 502 and executes step 505 based on the determination result in step 504, then in step 505, the transmitter sets a init to a1, that is, it should be noted that the transmitter updates a init from a2 to a1. In addition, N SYM,init also needs to be redetermined according to formula (16). Then, the transmitter updates N init and N SYM,init based on a pld,u = a1 and the redetermined N avbits,u . Furthermore, N shrt,u and N punc,u are updated based on the updated N pld,u and N avbits,u , and the updated N shrt,u and N punc,uBased on this, it is determined whether the LDPC additional symbol segment condition is satisfied.

[0236] 506: The transmitter determines whether the LDPC additional symbol segment condition is satisfied.

[0237] Similar to the aforementioned Solution 1, the transmitter determines whether the LDPC additional symbol segment condition is satisfied in both Step 504 and Step 506. However, the LDPC additional symbol segment condition in Step 504 is set based on a init = a2, that is, it is set based on a2. In Step 505, a init is updated to a1. Therefore, the LDPC additional symbol segment condition in Step 506 is set based on a init = a1, that is, it is set based on a1.

[0238] 507: The transmitter sets the LDPC additional symbol segment field of the first PPDU according to whether the LDPC additional symbol segment condition is satisfied.

[0239] As described above, in Step 504, when the transmitter determines that the LDPC additional symbol segment condition is not satisfied, the transmitter directly executes Step 507. In this case, the transmitter sets the LDPC additional symbol segment field to a second value, and the second value indicates that there is no need to add an LDPC additional symbol segment, and the LDPC additional symbol segment field carries 2.

[0240] When setting the LDPC additional symbol segment field based on the determination result in Step 506, the transmitter sets the LDPC additional symbol segment field according to the following principle.

[0241] When the LDPC additional symbol segment condition is satisfied, the transmitter sets the LDPC additional symbol segment field to 1, and the LDPC additional symbol segment field carries 2.

[0242] When the LDPC additional symbol segment condition is not satisfied, the transmitter sets the LDPC additional symbol segment field to 0, and the LDPC additional symbol segment field carries 1.

[0243] 508: The transmitter calculates the duration of the padding part of the EHT-SIG field of the first PPDU.

[0244] Specifically, the transmitter calculates the duration of the padding part of the EHT-SIG field (hereinafter referred to as T additional_EHT_SIG as shown) according to Equation (22).

Number

Number

Number

[0245] Note that the remaining duration T additional_EHT_SIG_est in Equation (22) is the remaining duration obtained after being updated according to Equation (21).

[0246] 509: The transmitter generates the first PPDU.

[0247] FIG. 13 shows an EHT PPDU obtained after padding the EHT-SIG field according to the present application. After the EHT-SIG field is padded (or, based on the initial part of the EHT-SIG field, a padding part is added to the EHT-SIG field), it can be seen that the duration of the preamble is also increased accordingly. Specifically, the duration of the padding part of the EHT-SIG field is added based on the initial duration of the preamble.

[0248] 510: The transmitter transmits the first PPDU.

[0249] In Solution 3, the transmitter pads the EHT-SIG field based on the limit for the first time to align the end time of the first PPDU with the first time. Compared with the aforementioned Solutions 1 and 2, in Solution 3, the duration of the PE field can be freely selected and is more flexible.

[0250] In addition, the procedure in FIG. 12 is only intended to facilitate the understanding of the solution of the present application, and it should be understood that the process by which the transmitter generates the first PPDU is divided into different steps. In fact, in the present application, the process by which the transmitter generates the first PPDU is a process in which the transmitter determines the duration of each field and sets the field of each field. Therefore, steps 507 and 508 may also be combined into step 509 and regarded as steps in the process of generating the first PPDU. Therefore, the steps in FIG. 12 are only used as examples, and these steps may be combined into fewer steps or divided into more steps. This should not constitute any limitation to the solution itself.

[0251] Similarly, to simplify the complexity of selecting the pre-forward error correction padding factor and to reduce the computational complexity in the selection process, Solution 4 is provided below.

[0252] Solution 4

[0253] FIG. 14 is another flowchart related to generating and transmitting a first PPDU by a transmitter according to the present application.

[0254] 601: The transmitter selects the duration T of the PE field and calculates N. PE and calculates N. SYM

[0255] 602: The transmitter selects a2 based on T and the nominal packet padding capability value of the receiver. PE and the nominal packet padding capability value of the receiver.

[0256] 603: The transmitter calculates N and N based on a = a1 and performs coding. Here, a1 is determined according to a2. init = a1, calculates N pld,u and N avbits,u

[0257] 604: The transmitter calculates the duration of the padding part of the EHT-SIG field.

[0258] 605: The transmitter generates the first PPDU.

[0259] Specifically, the transmitter sets the LDPC additional symbol segment field of the first PPDU. The transmitter sets the LDPC additional symbol segment field to 1, and the LDPC additional symbol segment field carries 2.

[0260] 606: The transmitter transmits the first PPDU.

[0261] ​​In Solution 4, in addition to the duration of the PE field being more flexible and freely selectable, the transmitter does not need to calculate whether the LDPC additional symbol segment condition is satisfied. As a result, the process of selecting the pre-forward error correction padding factor is significantly simplified, and it can be seen that the computational complexity and the amount of calculation are reduced.

[0262] In addition to the PE field and the EHT-SIG field, PPDU alignment can also be implemented by controlling the duration of the EHT-LTF field.

[0263] (3) EHT-LTF field.

[0264] When the type of the EHT-LTF field of the first PPDU is 1x EHT-LTF (in this case, the duration of each symbol in the EHT-LTF field excluding the GI part is 3.2 microseconds), or 2x EHT-LTF (in this case, the duration of each symbol in the EHT-LTF field excluding the GI part is 6.4 microseconds), the transmitter can implement PPDU alignment by padding the EHT-LTF field.

[0265] In other words, in this solution, the EHT-LTF field includes an initial part and a padding part. The process of calculating the duration of the padding part of the EHT-LTF field is the same as the process of calculating the padding part of the EHT-SIG field, and only the formula for calculating the padding part of the EHT-SIG field needs to be replaced with the following formula (23).

Number

[0266] In summary, the transmitter first obtains the remaining duration through calculation by using Solution 3 or Solution 4, and then can calculate the duration of the padding part of the EHT-LTF field according to formula (23). The EHT-LTF field of the first PPDU finally generated by the transmitter includes an initial part and a padding part.

[0267] The duration granularity of each symbol except for the guard interval in 1x EHT-LTF and 2x EHT-LTF is relatively small and close to 4 microseconds, and can meet the alignment requirements. Therefore, it should be understood that the EHT-LTF field is selected to be padded in order to perform PPDU alignment. In addition, herein, when Solution 3 or Solution 4 is used in combination with the solution for padding the EHT-LTF, only the total length of the padding part of the EHT-LTF field and the EHT-SIG field needs to be as close as possible to the remaining duration T additional_EHT_SiG_est for PPDU alignment.

[0268] Those skilled in the art will know how to calculate the duration of the padding part of the EHT-LTF field by referring to the aforementioned process of calculating the duration of the padding part of the EHT-SIG field. Details are not described again here to avoid repetition of the description.

[0269] (4) Delay the transmission time of the first PPDU.

[0270] In this solution, the transmitter first needs to calculate the remaining duration according to formula (24).

Number

[0271] After obtaining the remaining duration, the transmitter delays the start time of the first PPDU. Specifically, the delayed duration may be the remaining duration T additional_EHT_SiG_est in the period.

[0272] FIG. 15 is a schematic diagram related to performing first PPDU alignment by delaying the transmission time of the first PPDU according to the present application. As shown in FIG. 15, the transmitter calculates the remaining duration based on the first duration, and then delays the start time of the first PPDU after the remaining duration.

[0273] It should be noted that when the delay time is excessively long, the air interface may be preempted by a third-party device, and the transmitter may miss the transmission opportunity. Therefore, the transmitter can delay the start time of the first PPDU in combination with the above solution or its implementation to control the delayed duration not to exceed a threshold, for example, 4 microseconds.

[0274] (5) Combine the above solutions.

[0275] The above describes several solutions for implementing PPDU alignment. Based on this, those skilled in the art can combine the foregoing solutions or any one implementation of the solutions to implement PPDU alignment.

[0276] Several solutions for implementing EHT MU PPDU alignment are described above, and solutions for implementing EHT TB PPDU alignment are described below.

[0277] 2. EHT TB PPDU Alignment

[0278] As described above, for the EHT TB PPDU, the AP first transmits a trigger frame. To perform PPDU alignment, it is first necessary to ensure that as many trigger frames as possible on different links are aligned.

[0279] To ensure trigger frame alignment as much as possible, the transmitter may select different types of PPDUs to carry the trigger frame on different links.

[0280] FIG. 16 shows the structures of several different types of PPDUs according to the present application. In FIG. 16, (a), (b), and (c) are a non-High Throughput (non-HT) PPDU, a High Throughput (HT) PPDU, and a very high throughput (VHT) PPDU, respectively. The length of each symbol of the three types of PPDUs is 4 microseconds, and there is no PE field. Therefore, the alignment requirement using a 4-microsecond error can be easily satisfied.

[0281] Since the length of each symbol of the three types of PPDUs is 4 microseconds, the amount of symbols of the first PPDU can be calculated according to the following formula.

Number

Number

[0282] When the transmitter uses a HE PPDU to carry a trigger frame, the HE PPDU has four formats: HE SU PPDU, HE MU PPDU, HE ER SU PPDU, and HE TB PPDU. As shown in FIG. 17, the trigger frame can be carried in the first three formats.

[0283] FIG. 17 shows several HE PPDU formats according to the present application. In FIG. 17, (a), (b), and (c) are HE SU PPDU, HE MU PPDU, and HE ER SU PPDU, respectively. The three formats are similar to the EHT MU PPDU, and any one of the solutions for aligning the above-described EHT MU PPDU can be used.

[0284] When carrying a trigger frame and the start times of the PPDUs on two or more links are the same, the transmitter selects PPDUs of the same length, and as a result, the alignment of the trigger frame can be guaranteed.

[0285] However, for the triggered EHT TB PPDU, when the AP generates a trigger frame, it can be guaranteed that the EHT TB PPDUs transmitted on all links are aligned within the error range, provided that the same uplink length is selected for all links.

[0286] Furthermore, the AP can select the same duration of the PE field, the same number of symbols in the data field, the same guard interval and the same type of the EHT-LTF field, the same number of symbols in the EHT-LTF field, the same pre-FEC padding factor, the same duration of the LDPC additional symbol segment field, and the same duration of the PE unambiguity field to simplify the factor selection and perform the alignment.

[0287] FIG. 18 is a schematic diagram related to implementing EHT TB PPDU alignment according to the present application.

[0288] As shown in FIG. 18, it is assumed that the transmitter triggers the receiver to transmit EHT TB PPDU1 on Link 1 by using Trigger Frame 1, and triggers the receiver to transmit EHT TB PPDU2 on Link 2 by using Trigger Frame 2. To perform the alignment between EHT TB PPDU1 and EHT TB PPDU2, the transmitter first ensures that the end time of Trigger Frame 1 is aligned with the end time of Trigger Frame 2. Based on this, the transmitter selects EHT TB PPDU1 and EHT TB PPDU2 with the same uplink length to perform the alignment between EHT TB PPDU1 and EHT TB PPDU2.

[0289] Similar to the EHT MU PPDU alignment in the foregoing solution, the EHT TB PPDU alignment can be an alignment within a specific error range. For example, the time interval between the end time of EHT TB PPDU1 and the end time of EHT TB PPDU2 is within a specific error range, and the error range can be, for example, 4 microseconds or 8 microseconds.

[0290] In FIGS. 1, 16, and 17, * represents multiplication.

[0291] In addition, in the equations in the embodiments of the present application

Number

Number

[0292] The above details a method for transmitting a PPDU in this application. The following describes a communication device for transmitting a PPDU provided in this application.

[0293] FIG. 19 is a schematic block diagram of a communication device according to this application. As shown in FIG. 19, the communication device 1000 includes a processing unit 1100 and a transmission unit 1300. Optionally, the communication device may further include a reception unit 1200 as shown by the dashed box in FIG. 19.

[0294] Optionally, the communication device 1000 may correspond to a transmitter in this embodiment of this application. In this case, each part of the communication device 1000 is configured to implement the following functions.

[0295] The processing unit 1100 controls the duration of one or more fields among the PE field, the EHT-SIG field, and the EHT-LTF field of the first PPDU, and / or delays the transmission time of the first PPDU, so that the error between the end time of the first PPDU and the first time is not greater than the error threshold.

[0296] The transmission unit 1300 is configured to transmit the first PPDU.

[0297] Optionally, in one embodiment, the first PPDU includes a preamble, a data field, and a PE field. The duration of the PE field is determined based on a first duration, the duration of the preamble of the first PPDU, and the duration of the symbols in the data field. And the first duration is the duration between the first time and the start time of the first PPDU.

[0298] Optionally, in one embodiment, the number of symbols in the data field is determined based on the first duration, the duration of the preamble, and the duration of the symbols in the data field.

[0299] Optionally, in one embodiment, the first PPDU includes a preamble, a data field, and a PE field. The preamble includes an EHT-SIG field, and the EHT-SIG field includes an initial portion and a padding portion.

[0300] The duration of the padding portion in the EHT-SIG field is determined based on the first duration, the initial duration of the preamble, the duration of the PE field, and the duration of the symbols in the data field. The initial duration of the preamble does not include the duration of the padding portion in the EHT-SIG field. And the first duration is the duration between the first time and the start time of the first PPDU.

[0301] The duration of the padding portion is a multiple of 4 microseconds.

[0302] Optionally, in one embodiment, the number of symbols in the data field is determined based on the first duration, the initial duration of the preamble, the duration of the PE field, and the duration of the symbols in the data field.

[0303] Optionally, in one embodiment, the EHT-SIG field of the first PPDU carries a low-density parity check (LDPC) additional symbol segment field.

[0304] The LDPC additional symbol segment field is set to be a second value, the EHT-SIG field carries a second pre-forward error correction padding factor, the second value indicates that no LDPC additional symbol segment needs to be added, the LDPC additional symbol segment field is set when the LDPC additional symbol segment condition is not met, and the LDPC additional symbol segment condition is set based on the second pre-forward error correction padding factor. The second pre-forward error correction padding factor is determined based on the duration of the PE field and the nominal packet padding capability of the receiver.

[0305] The LDPC additional symbol segment field is set to be a first value, the EHT-SIG field carries a second pre-forward error correction padding factor, the first value indicates that an LDPC additional symbol segment needs to be added, the LDPC additional symbol segment field is set when the LDPC additional symbol segment condition is met, and the LDPC additional symbol segment condition is set based on the first pre-forward error correction padding factor. The first pre-forward error correction padding factor is determined based on the duration of the PE field and the nominal packet padding capability of the receiver.

[0306] The LDPC additional symbol segment field is set to be a second value, the EHT-SIG field carries a first pre-forward error correction padding factor, the second value indicates that no LDPC additional symbol segment needs to be added, the LDPC additional symbol segment field is set when the LDPC additional symbol segment condition is not met, and the LDPC additional symbol segment condition is set based on the first pre-forward error correction padding factor. The first pre-forward error correction padding factor is determined based on the duration of the PE field and the nominal packet padding ability of the receiver.

[0307] In this embodiment of the present application, the first pre-forward error correction padding factor is determined based on the second pre-forward error correction padding factor, and the first PPDU is coded by using the first pre-forward error correction padding factor. As a result, the duration that can be used by the receiver to decode the first PPDU is extended compared to the duration of coding the first PPDU by using the second pre-forward error correction padding factor.

[0308] Optionally, in one embodiment, the EHT-SIG field of the first PPDU carries a low-density parity-check LDPC additional symbol segment field, the LDPC additional symbol segment field is set to be a first value, the LDPC additional symbol segment field carries a second pre-forward error correction padding factor, the first value indicates that an LDPC additional symbol segment needs to be added, and the second pre-forward error correction padding factor is determined based on the duration of the PE field and the nominal packet padding ability of the receiver.

[0309] Optionally, in one embodiment, the first pre-forward error correction padding factor and the second pre-forward error correction padding factor satisfy the following formula.

Equation

[0310] Here, a1 represents the first pre-forward error correction padding factor, and a2 represents the second pre-forward error correction padding factor.

[0311] Optionally, in one embodiment, the duration of the PE field is increased by 4 microseconds.

[0312] The duration of the PE field is increased by 4 microseconds in the following cases. The LDPC additional symbol segment condition is satisfied, and after the LDPC additional symbol segment is added, the requirement for the nominal packet padding ability of the receiver is not satisfied, the remaining duration is 4 microseconds or more, and the duration of the PE field does not reach the maximum allowable duration.

[0313] The LDPC additional symbol segment condition is set based on the second pre-forward error correction padding factor, and the second pre-forward error correction padding factor is determined based on the duration of the PE field obtained before 4 microseconds are added and the nominal packet padding ability of the receiver.

[0314] The remaining duration is determined based on the first duration, the duration of the preamble, the duration of the symbols in the data field, and the duration of the PE field obtained before 4 microseconds are added.

[0315] In the above implementation, the receiving unit 1200 and the transmitting unit 1300 may also be integrated into one transceiver unit and have both receiving and transmitting functions. This is not limited in this specification.

[0316] In an embodiment of the transmitter corresponding to the communication device 1000, the processing unit 1100 is configured to execute processes and / or operations implemented inside the transmitter in addition to the transmission operation and the reception operation. The receiving unit 1200 is configured to execute the reception operation, and the transmitting unit 1300 is configured to execute the transmission operation.

[0317] For example, in FIG. 5, the processing unit 1100 executes step 210, and the transmitting unit 1300 executes step 220.

[0318] As another example, in FIG. 6, the processing unit 1100 executes steps 301 to 307, and the transmitting unit 1300 executes step 308.

[0319] As another example, in FIG. 9, the processing unit 1100 executes steps 401 to 404, and the transmitting unit 1300 executes step 405.

[0320] As another example, in FIG. 11, the processing unit 1100 executes steps 501 to 509, and the transmitting unit 1300 executes step 510.

[0321] As another example, in FIG. 14, the processing unit 1100 executes steps 601 to 605, and the transmitting unit 1300 executes step 606.

[0322] FIG. 20 is a schematic diagram related to the configuration of a communication device according to the present application. As shown in FIG. 20, the communication device 10 includes one or more processors 11, one or more memories 12, and one or more communication interfaces 13. The processor 11 is configured to control the communication interface 13 to receive and transmit signals. The memory 12 is configured to store a computer program. The processor 11 is configured to call the computer program from the memory 12 and execute the computer program. As a result, the communication device 10 executes the processes executed by the transmitter in the embodiment of the method of the present application.

[0323] For example, the processor 11 may have the functions of the processing unit 1100 shown in FIG. 19, and the communication interface 13 may have the functions of the receiving unit 1200 and / or the transmitting unit 1300 shown in FIG. 19. Specifically, the processor 11 may be configured to execute processes or operations executed inside the communication device, and the communication interface 13 is configured to execute the transmitting operation and / or the receiving operation executed by the communication device.

[0324] In one implementation, the communication device 10 may be a transmitter in the embodiment of the method. In this embodiment, the communication interface 13 may be a transceiver. The transceiver may include a receiver and / or a transmitter. Optionally, the processor 11 may be a baseband device, and the communication interface 13 may be a radio frequency device.

[0325] In another implementation, the communication device 10 may be a chip (or chip system) installed in the transmitter. In this implementation, the communication interface 13 may be an interface circuit or an input / output interface.

[0326] Optionally, the dashed box behind a component (e.g., a processor, a memory, or a communication interface) in FIG. 20 indicates that two or more components may exist.

[0327] In another implementation, the communication interface 13 may include a radio frequency circuit and an antenna. The radio frequency circuit and the antenna may be arranged independently of the processor performing baseband processing. For example, in a distributed scenario, the radio frequency circuit and the antenna may be arranged away from and independently of the communication device.

[0328] The processor may be configured to execute, for example, but not limited to, baseband-related processing, and the transceiver may be configured to execute, for example, but not limited to, radio frequency reception and transmission. Each of the above components may be provided on separate chips, or at least a part of them may be provided on the same chip. For example, the processor may be further divided into an analog baseband processor and a digital baseband processor. The analog baseband processor and the transceiver may be integrated on the same chip, and the digital baseband processor may be arranged on a separate chip. With the continuous development of integrated circuit technology, more and more components can be integrated on the same chip. For example, the digital baseband processor may be integrated on the same chip with a plurality of application processors (e.g., but not limited to, a graphics processor and a multimedia processor). The chip may be referred to as a system on chip. Whether the components are arranged independently on different chips or integrated and arranged on one or more chips generally depends on specific requirements of product design. The specific implementation of the foregoing components is not limited in this embodiment of the present invention.

[0329] Optionally, in the embodiments of the aforementioned apparatus, the memory and the processor may be physically independent units from each other, or the memory and the processor may be integrated together. This is not limited in this specification.

[0330] In addition, this application further provides a computer-readable storage medium. The computer-readable storage medium stores computer instructions. When the computer instructions are executed on a computer, the operations and / or processes executed by the transmitter in the embodiments of the method of this application are executed.

[0331] In addition, this application further provides a computer program product. The computer program product includes computer program code or instructions. When the computer program code or instructions are executed on a computer, the operations and / or processes executed by the transmitter in the embodiments of the method of this application are executed.

[0332] In addition, this application further provides a chip. The chip includes a processor, a memory configured to store a computer program is disposed independently of the chip, and the processor is configured to execute the computer program stored in the memory, as a result, the transmitter in which the chip is installed executes the operations and / or processes executed by the transmitter in any one of the embodiments of the method.

[0333] Furthermore, the chip may include a communication interface. The communication interface may be an input / output interface, an interface circuit, etc. Furthermore, the chip may include a memory.

[0334] Optionally, one or more processors may be present, one or more memories may be present, and one or more memories may be present.

[0335] In addition, the present application further provides a communication device (which may be, for example, a chip or a chip system) including a processor and a communication interface. The communication interface is configured to receive (or referred to as input) data and / or information, and transmit the received data and / or information to the processor. The processor processes the data and / or information. The communication interface is further configured to output (or referred to as output) the data and / or information processed by the processor, as a result, the operations and / or processes executed by the transmitter in any one of the method embodiments are executed.

[0336] In addition, the present application further provides a communication device including at least one processor. The at least one processor is coupled to at least one memory, and the at least one processor is configured to execute a computer program or instructions stored in the at least one memory, enabling the communication device to execute the operations and / or processes executed by the transmitter in any one of the method embodiments.

[0337] In addition, the present application further provides a communication device including a processor and a memory. Optionally, the communication device may further include a transceiver. The memory is configured to store a computer program. The processor is configured to call, execute the computer program stored in the memory, and control the transceiver to receive and transmit signals, as a result, the communication device executes the operations and / or processes executed by the transmitter in any one of the method embodiments.

[0338] The memory in the embodiments of this application may be volatile memory or non-volatile memory, or may include both volatile memory and non-volatile memory. The non-volatile memory can be read-only memory (ROM), programmable ROM (PROM), erasable PROM (EPROM), electrically erasable PROM (EEPROM), or flash memory. The volatile memory may be random access memory (RAM) and is used as an external cache. By way of example and not limitation, many forms of RAM are available, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synclink DRAM (SLDRAM), and direct rambus RAM (DRRAM). It should be noted that the memory in the systems and methods described herein includes, but is not limited to, any of these and other suitable types of memory.

[0339] All or part of the methods provided in the foregoing embodiments may be implemented by using software, hardware, firmware, or any combination thereof. When software is used to implement the embodiments, all or part of the embodiments may be implemented in the form of a computer program product. The computer program product may include one or more computer instructions. When the computer program instructions are loaded and executed on a computer, procedures or functions are generated in whole or in part according to the embodiments of the present application. The computer may be a general-purpose computer, a dedicated computer, a computer network, or another programmable device. The computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions may be transmitted from a website, computer, server, or data center to another website, computer, server, or data center by a wired (e.g., coaxial cable, optical fiber, or digital subscriber line) or wireless (e.g., infrared, wireless, or microwave) means. The computer-readable storage medium may be any available medium accessible by a computer or a data storage device integrating one or more available media, such as a server or a data center.

[0340] To clearly describe the technical solutions in the embodiments of this application, numbers such as "first" and "second" are used in the embodiments of this application to distinguish the same items or similar items that basically have the same functions and purposes. For example, the first pre-forward error correction padding factor and the second pre-forward error correction padding factor are only used to distinguish two different pre-forward error correction padding factors. A person skilled in the art will understand that numbers such as "first" and "second" do not limit the quantity and execution order, and the words "first" and "second" do not indicate a clear difference.

[0341] In the embodiments of this application, "at least one" means one or more, and "a plurality of" means two or more. The term "and / or" describes the relationship between related objects and indicates that three relationships may exist. For example, A and / or B may indicate the following three cases: A exists alone, both A and B exist, and B exists alone, where A and B may be singular or plural. The character " / " generally indicates an "or" relationship between related objects. At least one of the following items (pieces), or a similar expression, indicates any combination of these items and includes any combination of one item (piece) or multiple items (pieces). For example, at least one of a, b, or c may represent a, b, c, a and b, a and c, b and c, or a and b and c, where a, b, and c may be singular or plural.

[0342] A person skilled in the art can recognize that, in combination with the examples described in the embodiments disclosed in this specification, the units and algorithm steps can be implemented by electronic hardware or a combination of computer software and electronic hardware. Whether a function is executed by hardware or by software depends on the specific application of the technical solution and design constraints. A person skilled in the art may use different methods to implement the functions described for each specific application, but such implementation should not be considered to exceed the scope of this application.

[0343] A person skilled in the art will clearly understand that, for the sake of simplicity of description, the detailed operation processes of the above-mentioned systems, devices, and units can refer to the corresponding processes in the embodiments of the above-mentioned methods. Details will not be described again in this specification.

[0344] In this application, unless otherwise specified, the same or similar parts of the embodiments may refer to each other. In the embodiments of this application and the implementation / implementation methods in the embodiments, unless otherwise specified or logical contradictions do not occur, the terms and / or descriptions are consistent, and can be referred to each other between different embodiments and between the implementation / implementation methods in the embodiments. The technical features in different embodiments and the implementation / implementation methods in the embodiments can be combined to form new embodiments, implementations, or implementation methods based on their internal logical relationships. The following embodiments of this application are not intended to limit the protection scope of this application.

[0345] In some embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the described embodiments of the apparatuses are merely examples. For example, the division into units is merely a logical function division, and in actual implementation, other divisions may be possible. For example, a plurality of units or components may be combined or integrated into another system, or some features may be ignored or not executed. Additionally, the couplings, direct couplings, or communication connections shown or discussed can be implemented via some interfaces. The indirect couplings or communication connections between apparatuses or units can be implemented in electronic, mechanical, or other forms.

[0346] The units described as separate parts may or may not be physically separate, and the parts shown as units may or may not be physical units. They may be located in one position or dispersed over a plurality of network units. Some or all of the units can be selected according to actual requirements to achieve the purpose of the solution of the embodiment.

[0347] In addition, the functional units in the embodiments of this application may be integrated into one processing unit, and each unit may physically exist alone, or two or more units may be integrated into one unit.

[0348] When the function is implemented in the form of a software functional unit and sold or used as an independent product, the function can be stored in a computer-readable storage medium. Based on such an understanding, essentially the technical solution of this application, or the part that contributes to the prior art, or a part of the technical solution, can be implemented in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for instructing a computer device (which can be a personal computer, a server, or a network device) to execute all or some of the steps of the method described in the embodiments of this application. The aforementioned storage medium includes any medium that can store program code, such as a USB flash drive, a removable hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0349] The foregoing description is merely a specific implementation of this application and is not intended to limit the protection scope of this application. Any modification or substitution that can be easily conceived by those skilled in the art within the technical scope disclosed in this application shall fall within the protection scope of this application. Therefore, the protection scope of this application shall follow the protection scope of the claims.

Claims

1. A method for transmitting a Physical Layer Protocol Data Unit (PPDU), comprising: adjusting the duration of one or more fields among the Packet Extension (PE) field, the Extended High Throughput Signal (EHT-SIG) field, and the Extended High Throughput Long Training Field (EHT-LTF) field of a first PPDU, wherein an error between an end time of the first PPDU and a first time is not greater than an error threshold, and the first time is a target of the end time of the first PPDU; transmitting the first PPDU; and the first PPDU includes a preamble, a data field, and a PE field; the preamble includes an EHT-SIG field; and the EHT-SIG field includes an initial portion and a padding portion; a duration of the padding portion in the EHT-SIG field is determined based on a first duration, an initial duration of the preamble, a duration of the PE field, and a duration of symbols in the data field; the initial duration of the preamble does not include the duration of the padding portion in the EHT-SIG field; and the first duration is a duration between the first time and a start time of the first PPDU; the duration of the padding portion is a multiple of 4 microseconds. A method.

2. The duration of the PE field is determined based on the first duration, a duration of a preamble of the first PPDU, and a duration of symbols in the data field. The method according to claim 1.

3. The number of symbols in the data field is determined based on the first duration, the duration of the preamble, and the duration of the symbols in the data field. The method according to claim 2.

4. The number of symbols in the data field is determined based on the first duration, the initial duration of the preamble, the duration of the PE field, and the duration of the symbols in the data field. The method according to claim 1.

5. The EHT-SIG field of the first PPDU carries a low-density parity-check (LDPC) additional symbol segment field. The LDPC additional symbol segment field is set to a second value. The EHT-SIG field carries a second pre-forward error correction padding factor. The second value indicates that no LDPC additional symbol segment needs to be added. The LDPC additional symbol segment field is set when the LDPC additional symbol segment condition is not met, and The LDPC additional symbol segment condition is set based on the second pre-forward error correction padding factor. The second pre-forward error correction padding factor is determined based on the duration of the PE field and the nominal packet padding ability of the receiver, or The LDPC additional symbol segment field is set to a first value. The EHT-SIG field carries a second pre-forward error correction padding factor. The first value indicates that an LDPC additional symbol segment needs to be added. The LDPC additional symbol segment field is set when the LDPC additional symbol segment condition is met, and The LDPC additional symbol segment condition is set based on a first pre-forward error correction padding factor, The first pre-forward error correction padding factor is determined based on the duration of the PE field and the nominal packet padding ability of the receiver, or The LDPC additional symbol segment field is set to a second value, The EHT-SIG field carries a first pre-forward error correction padding factor, The second value indicates that no LDPC additional symbol segment needs to be added, The LDPC additional symbol segment field is set when the LDPC additional symbol segment condition is not satisfied, The LDPC additional symbol segment condition is set based on the first pre-forward error correction padding factor, The first pre-forward error correction padding factor is determined based on the duration of the PE field and the nominal packet padding ability of the receiver, The method according to claim 2.

6. The EHT-SIG field of the first PPDU carries a low-density parity-check (LDPC) additional symbol segment field, The LDPC additional symbol segment field is set to a first value, The LDPC additional symbol segment field carries a second pre-forward error correction padding factor, The first value indicates that an LDPC additional symbol segment needs to be added, The second pre-forward error correction padding factor is determined based on the duration of the PE field and the nominal packet padding ability of the receiver, The method according to claim 2.

7. The first pre-forward error correction padding factor and the second pre-forward error correction padding factor satisfy the following formula, 【Number 1】 Here, a1 represents the first pre-forward error correction padding factor, and a2 represents the second pre-forward error correction padding factor. The method according to claim 5.

8. The duration of the PE field is The LDPC additional symbol segment condition is satisfied, after the LDPC additional symbol segment is added, the requirements regarding the nominal packet padding ability of the receiver are not satisfied, the remaining duration is 4 microseconds or more, and the duration of the PE field does not reach the allowable maximum duration, when this occurs, it is increased by 4 microseconds, the LDPC additional symbol segment condition is set based on the second pre-forward error correction padding factor, and the second pre-forward error correction padding factor is determined based on the duration of the PE field obtained before 4 microseconds are added and the nominal packet padding ability of the receiver, and the remaining duration is determined based on the first duration, the duration of the preamble, the duration of the symbols in the data field, and the duration of the PE field obtained before 4 microseconds are added. The method according to claim 1.

9. A communication device for transmitting a physical layer protocol data unit (PPDU), comprising a processing unit, Adjust the duration of one or more of the packet extension (PE) field, the extremely high throughput signal (EHT-SIG) field, and the extremely high throughput long training field (EHT-LTF) field of the first PPDU, and the error between the end time of the first PPDU and the first time is not greater than the error threshold, and the first time is the target of the end time of the first PPDU. A processing unit configured as follows: A transmission unit configured to transmit the first PPDU. Including The first PPDU includes a preamble, a data field, and a PE field. The preamble includes an EHT-SIG field, and The EHT-SIG field includes an initial part and a padding part. The duration of the padding part in the EHT-SIG field is determined based on a first duration, an initial duration of the preamble, a duration of the PE field, and a duration of symbols in the data field. The initial duration of the preamble does not include the duration of the padding part in the EHT-SIG field, and The first duration is the duration between the first time and the start time of the first PPDU. The duration of the padding part is a multiple of 4 microseconds. A communication device.

10. The duration of the PE field is determined based on the first duration, the duration of the preamble of the first PPDU, and the duration of symbols in the data field. The communication device according to claim 9.

11. The number of symbols in the data field is determined based on the first duration, the duration of the preamble, and the duration of symbols in the data field. The communication device according to claim 10.

12. The number of symbols in the data field is determined based on the first duration, the initial duration of the preamble, the duration of the PE field, and the duration of the symbols in the data field. The communication device according to claim 9.

13. The EHT-SIG field of the first PPDU carries a low-density parity-check (LDPC) additional symbol segment field. The LDPC additional symbol segment field is set to a second value. The EHT-SIG field carries a second pre-forward error correction padding factor. The second value indicates that no LDPC additional symbol segment needs to be added. The LDPC additional symbol segment field is set when the LDPC additional symbol segment condition is not satisfied, and The LDPC additional symbol segment condition is set based on the second pre-forward error correction padding factor. The second pre-forward error correction padding factor is determined based on the duration of the PE field and the nominal packet padding ability of the receiver, or The LDPC additional symbol segment field is set to a first value. The EHT-SIG field carries a second pre-forward error correction padding factor. The first value indicates that an LDPC additional symbol segment needs to be added. The LDPC additional symbol segment field is set when the LDPC additional symbol segment condition is satisfied, and The LDPC additional symbol segment condition is set based on the first pre-forward error correction padding factor. The first pre-forward error correction padding factor is determined based on the duration of the PE field and the nominal packet padding ability of the receiver, or the LDPC additional symbol segment field is set to a second value, the EHT-SIG field carries the first pre-forward error correction padding factor, the second value indicates that no LDPC additional symbol segment needs to be added, the LDPC additional symbol segment field is set when the LDPC additional symbol segment condition is not satisfied, the LDPC additional symbol segment condition is set based on the first pre-forward error correction padding factor, the first pre-forward error correction padding factor is determined based on the duration of the PE field and the nominal packet padding ability of the receiver, The communication device according to claim 10.

14. The EHT-SIG field of the first PPDU carries a low-density parity-check (LDPC) additional symbol segment field, the LDPC additional symbol segment field is set to a first value, the LDPC additional symbol segment field carries a second pre-forward error correction padding factor, the first value indicates that an LDPC additional symbol segment needs to be added, the second pre-forward error correction padding factor is determined based on the duration of the PE field and the nominal packet padding ability of the receiver, The communication device according to claim 10.

15. The first pre-forward error correction padding factor and the second pre-forward error correction padding factor satisfy the following formula, 【Equation 2】 Here, a1 represents the first pre-forward error correction padding factor, and a2 represents the second pre-forward error correction padding factor. The communication device according to claim 13.

16. The duration of the PE field is The LDPC additional symbol segment condition is satisfied, After the LDPC additional symbol segment is added, the requirements regarding the nominal packet padding ability of the receiver are not satisfied, The remaining duration is 4 microseconds or more, and The duration of the PE field does not reach the maximum allowable duration, When this occurs, it is increased by 4 microseconds, The LDPC additional symbol segment condition is set based on the second pre-forward error correction padding factor, and The second pre-forward error correction padding factor is determined based on the duration of the PE field obtained before 4 microseconds are added and the nominal packet padding ability of the receiver, and The remaining duration is determined based on the first duration, the duration of the preamble, the duration of the symbols in the data field, and the duration of the PE field obtained before 4 microseconds are added. The communication device according to claim 9.

17. A communication device, The communication device includes a transceiver, and The communication device is configured to implement the method according to any one of claims 1 to 8. Communication device.

18. A computer-readable storage medium, The computer-readable storage medium includes a computer program or instructions, When the computer program or the instructions are executed on a computer, the computer can implement the method according to any one of claims 1 to 8. A computer-readable storage medium. **Claim 19** A chip, wherein the chip includes a processing circuit and transceiver pins, and when instructions are executed by the processing circuit, the chip can execute the method according to any one of claims 1 to 8. A chip.

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