CN117793794A

CN117793794A - Communication method and device in wireless local area network

Info

Publication number: CN117793794A
Application number: CN202211197919.5A
Authority: CN
Inventors: 白小飞; 倪一展; 应腾达; 王晨; 刘亚辉; 于健
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2022-09-29
Filing date: 2022-09-29
Publication date: 2024-03-29
Also published as: WO2024067077A1

Abstract

A communication method and device in WLAN are disclosed, which belong to WLAN technical field. A first communication device in a WLAN transmits a PPDU to a second communication device in the WLAN. The preamble of the PPDU includes a start field and an L-LTF immediately after the start field. The start field is greater than 8 microseconds in length and has a continuous 8 microsecond content that is the same as the content of the L-STF. The start field is used for automatic gain control adjustment. By replacing the L-STF with a start field in the preamble of the PPDU. The start field includes the contents of the L-STF to facilitate compatibility. The starting field is longer than the L-STF, so that the time constraint of a receiver for completing corresponding functions by using the field is relaxed, and the time requirements of the hardware with different performances for executing the functions of synchronization, signal detection, AGC and the like can be met, thereby improving the communication reliability of the WLAN in different application scenes.

Description

Communication method and device in wireless local area network

Technical Field

The present disclosure relates to the field of wireless local area networks (wireless local area network, WLAN), and in particular, to a communication method and apparatus in a WLAN.

Background

When a receiver in the WLAN receives signals, the power gain of the received signals needs to be adjusted, the power amplification is carried out on the received signals with the too low power, and the power attenuation is carried out on the received signals with the too high power, so that the received signals are finally adjusted to a proper power level, and the signal receiving performance of the receiver is ensured. The process by which the receiver adjusts the power gain of the received signal may be referred to as an automatic gain control (automatic gain control, AGC) adjustment process.

The receiver, upon receiving the physical layer protocol data unit (physical layer protocol data unit, PPDU), AGC adjusts the received signal power using a legacy short training field (short training field, STF) (L-STF for short) in the preamble (preamble) of the PPDU. In some cases, however, the receiver may not be able to perform AGC adjustments, which may affect normal communications in the WLAN.

Disclosure of Invention

The application provides a communication method and device in a WLAN, which improves the communication reliability in the WLAN.

In a first aspect, a PPDU is provided, a preamble of which includes a start field and a legacy long training field (long training field, LTF) (abbreviated L-LTF) immediately after the start field. The start field is greater than 8 microseconds in length and has a continuous 8 microsecond content that is the same as the content of the L-STF. In other words, the preamble of the PPDU includes a target field, an L-STF, and an L-LTF. The target field is the other content in the start field than the same continuous 8 microsecond content as the content of the L-STF. The target domain is adjacent to the L-STF, and the target domain and the L-STF precede the L-LTF. The length of the target field is greater than 0.

The present application replaces the legacy short training field with a start field in the preamble of the PPDU. The start field includes the contents of the conventional short training field to facilitate compatibility. And the starting field is longer than the traditional short training field, so that the time constraint that a receiver utilizes the field to complete corresponding functions (such as synchronization, signal detection, AGC and the like) is relaxed, and the time requirements of hardware with different performances for executing the functions of synchronization, signal detection, AGC and the like can be met, thereby improving the communication reliability of the WLAN in different application scenes. The method only needs to change the first field in the preamble, and has no influence on the subsequent fields, so that the subsequent processing of the PPDU by the communication equipment cannot be changed, and the method is simple to realize.

Optionally, the preamble of the PPDU includes a start field and an L-LTF, the first 8 microseconds of the content in the start field being identical to the content of the L-STF, and/or the last 8 microseconds of the content in the start field being identical to the content of the L-STF.

Optionally, a start field is used for automatic gain control adjustment.

Optionally, the other content in the start field than the same continuous 8 microsecond content as the content of the L-STF includes part or all of the content of one or more fields. The one or more fields include an L-STF, an L-LTF, a legacy Signal (SIG) domain (referred to as an L-SIG domain), a High Efficiency (HE) short training domain (referred to as an HE-STF), or a high efficiency long training domain (referred to as an HE-LTF). That is, the start field may be composed of a plurality of L-STFs, or of M L-STFs and N L-LTFs, or of P L-STFs and Q L-SIG domains, or of X L-STFs, Y L-LTFs and Z L-SIG domains, and so on. M, N, P, Q, X, Y, Z are positive numbers and M, P and X are each greater than or equal to 1.

Optionally, the other content in the start field than the same continuous 8 microsecond content as the content of the L-STF includes one or more of: at least 6L-STFs, at least 6L-LTFs, at least 12L-SIG domains, or a combination of at least 3L-STFs and at least 3L-LTFs.

For example, the content other than the same continuous 8-microsecond content as the content of the L-STF in the start field may include 6L-STF contents, or 6L-LTF contents, or 12L-SIG fields, or a combination of 3L-STF contents and 3L-LTF contents. In these examples, the total length of the start field is 56 microseconds. Optionally, the length of the start field is variable. For example, the examples above may be used in combination such that the total length of the start field exceeds 56 microseconds.

Optionally, the length of the start field is predefined or determined by negotiations between the communicating parties. The length of the start field is predefined and includes: the length of the start field is predefined in the WLAN protocol. The length of the start field is determined by negotiations of both parties of the communication, including: before the two communication parties start communication, the length of the start field is preconfigured in the two communication devices, or the two communication devices negotiate to determine the length of the start field through a message interaction mode, for example, the two communication devices can determine the length of the start field through message negotiation in the process of establishing a communication connection.

Optionally, the same continuous 8 microsecond content in the beginning field of the preamble of the PPDU as the content of the L-STF and the content in the PPDU located after the beginning field constitute a Non-high throughput (Non-HT) PPDU, a high throughput mixed format (high throughput mixed format, HT-MF) PPDU, a very high throughput (very high throughput, VHT) PPDU, a high efficiency single user (high efficiency single user, HE SU) PPDU, a high efficiency multi-user (high efficiency multi-user, HE MU) PPDU, a high efficiency extended range single user (high efficiency extended range single user, HE ER SU) PPDU, or a high efficiency trigger (high efficiency trigger-based, HE-TB) PPDU.

In a second aspect, a method of communication in a WLAN is provided. A first communication device in a WLAN transmits a PPDU to a second communication device in the WLAN. The preamble of the PPDU includes a start field and an L-LTF immediately after the start field. The start field is greater than 8 microseconds in length and has a continuous 8 microsecond content that is the same as the content of the L-STF. The PPDU may be a PPDU according to any of the first aspects.

In this application, the first communication device replaces the legacy short training field with the start field in the preamble of the PPDU transmitted to the second communication device. The start field includes the contents of the conventional short training field to facilitate compatibility. And the start field is longer than the traditional short training field, so that the time constraint of using the field to complete corresponding functions (such as synchronization, signal detection, AGC and the like) of the second communication equipment is relaxed, and the time requirements of executing the functions of synchronization, signal detection, AGC and the like by hardware with different performances can be met, thereby improving the communication reliability of the WLAN in different application scenes. The first field in the preamble is only required to be changed, and no influence is caused on the subsequent field, so that the second communication equipment is simple to realize, except for the time for completing the corresponding function by using the field, the subsequent processing of the PPDU by the second communication equipment is not required to be changed.

Optionally, the first 8 microseconds of the content in the start field is the same as the content of the L-STF and/or the last 8 microseconds of the content in the start field is the same as the content of the L-STF.

Optionally, a start field is used for automatic gain control adjustment.

Optionally, the other content in the start field than the same continuous 8 microsecond content as the content of the L-STF includes part or all of the content of one or more fields. The one or more fields include an L-STF, an L-LTF, an L-SIG domain, an HE-STF, or an HE-LTF.

Optionally, one implementation of the first communication device in the WLAN transmitting the PPDU to the second communication device in the WLAN includes: the first communication device transmits a PPDU to the second communication device over the millimeter wave band. That is, the first communication device and the second communication device both adopt millimeter wave radio frequency chips.

In the application, because the field length for AGC adjustment is increased in the preamble of the PPDU, for the communication equipment adopting the millimeter wave radio frequency chip, more time can be provided for AGC adjustment, and the situation that communication fails due to the fact that the communication fails because the communication is not performed for the regulated time length can be reduced or avoided, thereby improving the communication reliability.

Optionally, the length of the start field is predefined or determined by the first communication device and the second communication device negotiations.

Optionally, the continuous 8 microsecond content in the beginning field of the preamble of the PPDU that is identical to the content of the L-STF and the content in the PPDU that is located after the beginning field constitute a Non-HT PPDU, HT-MF PPDU, VHT PPDU, HE SU PPDU, HE MU PPDU, HE ER SU PPDU, or HE-TB PPDU.

In a third aspect, a method of communication in a WLAN is provided. A first communication device in a WLAN receives a PPDU from a second communication device in the WLAN. The preamble of the PPDU includes a start field and an L-LTF immediately after the start field. The start field is greater than 8 microseconds in length and has a continuous 8 microsecond content that is the same as the content of the L-STF. The PPDU may be a PPDU according to any of the first aspects. And the first communication equipment performs automatic gain control adjustment on the received signal power of the PPDU according to the length of the start field.

The first communication device performs automatic gain control adjustment on the received signal power of the PPDU according to the length of the start field, that is, the first communication device performs automatic gain control adjustment on the received signal power of the PPDU in the receiving duration of receiving the start field.

In the present application, the legacy short training field is replaced with a start field in the preamble of the PPDU received by the first communication device. The start field includes the contents of the conventional short training field to facilitate compatibility. And the start field is longer than the traditional short training field, so that the time constraint of the first communication device for completing corresponding functions (such as synchronization, signal detection, AGC and the like) by using the field is relaxed, and the time requirements of hardware with different performances for executing the functions of synchronization, signal detection, AGC and the like can be met, thereby improving the communication reliability of the WLAN in different application scenes. The first field in the preamble is only required to be changed, and no influence is caused on the subsequent field, so that the first communication equipment is simple to realize, except for the time for completing the corresponding function by using the field, the subsequent processing of the PPDU by the first communication equipment is not required to be changed.

Optionally, one implementation of the first communication device in the WLAN receiving a PPDU from the second communication device in the WLAN includes: the first communication device receives a PPDU from the second communication device over the millimeter wave band. That is, the first communication device and the second communication device both adopt millimeter wave radio frequency chips.

In the application, since the field length for AGC adjustment is increased in the preamble of the PPDU, for the first communication device adopting the millimeter wave radio frequency chip, more time can be provided for AGC adjustment, and the situation that communication fails due to the fact that the first communication device does not reach the AGC adjustment within a specified time period can be reduced or avoided, thereby improving the communication reliability.

In a fourth aspect, a communication device in a WLAN is provided. The apparatus comprises a plurality of functional modules that interact to implement the method of the second aspect and embodiments thereof and/or the third aspect and embodiments thereof. The plurality of functional modules may be implemented based on software, hardware, or a combination of software and hardware, and the plurality of functional modules may be arbitrarily combined or divided based on the specific implementation.

In a fifth aspect, a communication device in a WLAN is provided, comprising: a transceiver and an antenna. The transceiver is configured to transmit and receive PPDUs with antennas. The preamble of the PPDU includes a start field and an L-LTF immediately after the start field. The start field is greater than 8 microseconds in length. And the start field has a continuous 8 microsecond content identical to the content of the L-STF. The PPDU may be a PPDU according to any of the first aspects.

Optionally, the transceiver comprises a millimeter wave radio frequency chip.

In a sixth aspect, a computer readable storage medium is provided, on which instructions are stored which, when executed by a processor, implement the method of the above second aspect and embodiments thereof and/or the above third aspect and embodiments thereof.

In a seventh aspect, a chip is provided, the chip comprising programmable logic circuits and/or program instructions, which when the chip is run, implement the method of the second aspect and embodiments thereof and/or the third aspect and embodiments thereof described above.

Drawings

Fig. 1 is a schematic view of an application scenario provided in an embodiment of the present application;

fig. 2 is a schematic hardware structure of a communication device in a WLAN according to an embodiment of the present application;

FIG. 3 is a schematic diagram of the structure of a Non-HT PPDU;

fig. 4 is a schematic diagram of the structure of an HT-MF PPDU;

fig. 5 is a schematic diagram of the structure of a VHT PPDU;

fig. 6 is a schematic diagram of the structure of the HE SU PPDU;

fig. 7 is a schematic structural diagram of the HE MU PPDU;

fig. 8 is a schematic diagram of the structure of an HE ER SU PPDU;

fig. 9 is a schematic structural diagram of an HE-TB PPDU;

fig. 10 is a schematic structural diagram of a PPDU according to an embodiment of the present application;

fig. 11 is a schematic structural diagram of another PPDU according to an embodiment of the present application;

fig. 12 is a schematic structural diagram of a start field provided in an embodiment of the present application;

FIG. 13 is a schematic diagram of another start field according to an embodiment of the present application;

FIG. 14 is a schematic diagram of a structure of a further start field provided by an embodiment of the present application;

Fig. 15 is a schematic structural diagram of still another start field provided in an embodiment of the present application;

fig. 16 is a flowchart of a communication method in a WLAN according to an embodiment of the present application;

fig. 17 is a schematic structural diagram of a communication device in a WLAN according to an embodiment of the present application;

fig. 18 is a schematic structural diagram of a communication device in another WLAN according to an embodiment of the present application.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the present application more apparent, the embodiments of the present application will be described in further detail below with reference to the accompanying drawings.

The embodiment of the application is applied to the WLAN. The WLAN includes a plurality of communication devices. The plurality of communication devices may implement wireless communications in compliance with a WLAN protocol. Optionally, the communication devices in the WLAN include, but are not limited to, access devices or stations. The access device may be, for example, an Access Point (AP) or a customer premises equipment (customer premise equipment, CPE), etc. The site may be, for example, a wireless terminal such as a smart phone, a notebook computer, or a smart wearable device.

For example, fig. 1 is a schematic view of an application scenario provided in an embodiment of the present application. As shown in fig. 1, the application scenario includes a communication device 101 and a communication device 102. Communication between communication device 101 and communication device 102 may be via WLAN. Of course, other devices may be included in the application scenario, and the number and types of devices shown in fig. 1 are merely exemplary.

Optionally, the communication device 101 transmits a PPDU to the communication device 102. When the communication device 102 receives the PPDU, it needs to adjust the received signal power gain of the PPDU. If the received signal power of the PPDU is too low, the communication device 102 needs to amplify the received signal power of the PPDU. If the received signal power of the PPDU is too high, the communication device 102 needs to attenuate the received signal power of the PPDU. So that the received signal power of the PPDU is ultimately adjusted to an appropriate power level to enable the communication device 102 to successfully receive the PPDU. The entire process of the communication device 102 adjusting the received signal power gain of the PPDU, i.e., the AGC adjustment process.

AGC adjustment is mainly implemented by three parts, an AGC module, a control interface and an analog amplifier in the communication device. The AGC module is in the baseband processing circuit, the analog amplifier is in the radio frequency processing circuit, the control interface is a bridge connecting the baseband processing circuit and the radio frequency processing circuit, and the control interface can transmit control signals between the baseband processing circuit and the radio frequency processing circuit. In the specific implementation, the AGC module calculates the power adjustment mode of the received signal, and sends a power adjustment control word to the analog amplifier through the control interface, and then the analog amplifier adjusts the working gear according to the power adjustment control word, so as to realize gain adjustment of the power of the received signal.

For example, fig. 2 is a schematic hardware structure of a communication device in a WLAN according to an embodiment of the present application. As shown in fig. 2, the communication device 20 includes, but is not limited to, a transceiver 201 and an antenna 202. Optionally, with continued reference to fig. 2, the communication device 20 further includes a processor 203 and a memory 204. The processor 203, the memory 204 and the transceiver 201 are connected by a communication bus (not shown).

The transceiver 201 is used to perform transceiving actions of the communication device 20. Referring to fig. 2, the transceiver 201 includes a baseband processing circuit 2011 and a radio frequency processing circuit 2012. During signal transmission, the baseband signal is generated by the baseband processing circuit 2011, and is converted into a radio frequency signal by the radio frequency processing circuit 2012, and then the radio frequency signal is sent out from the air interface by the antenna 202. In the signal receiving process, the antenna 202 receives a radio frequency signal from the air interface, the radio frequency processing circuit 2012 converts the radio frequency signal into a baseband signal, and the baseband processing circuit 2011 receives the baseband signal.

With continued reference to fig. 2, the baseband processing circuit 2011 includes an AGC module, a control interface a1, a baseband signal processing module, and a data interface b1. The radio frequency processing circuit 2012 includes an analog amplifier, a control interface a2, a radio frequency signal processing module, and a data interface b2. The control interface a1 is connected to the control interface a2 for transmitting control signals, such as power adjustment control words, between the baseband processing circuit 2011 and the radio frequency processing circuit 2012. The data interface b1 and the data interface b2 are connected to each other and are used for transmitting baseband signals between the baseband processing circuit 2011 and the radio frequency processing circuit 2012. The AGC module is used for calculating a signal power adjustment mode. The analog amplifier is used to adjust the signal power gain. The AGC module is in communication connection with the analog amplifier through a control interface a1 and a control interface a 2. The baseband signal processing module is used for generating a baseband signal and receiving the baseband signal. The radio frequency signal processing module is used for performing frequency conversion processing on the signals, for example, performing frequency conversion processing on the baseband signals to obtain radio frequency signals, and performing frequency conversion processing on the radio frequency signals to obtain the baseband signals. The baseband signal processing module and the radio frequency signal processing module are in communication connection through a data interface b1 and a data interface b2. Optionally, the baseband signal processing module includes an analog-to-digital converter and a digital-to-analog converter for performing conversion between digital signals and analog signals. Alternatively, the radio frequency signal processing module includes an analog-to-digital converter and a digital-to-analog converter for converting between digital signals and analog signals.

The baseband processing circuit 2011 and the radio frequency processing circuit 2012 described above are implemented on a hardware basis. For example, the baseband processing circuit 2011 is a baseband chip supporting the WLAN protocol, and is responsible for generating and receiving baseband signals according to the WLAN protocol. The rf processing circuit 2012 is an rf chip. For example, the radio frequency processing circuit 2012 may be a millimeter wave radio frequency chip, which is responsible for frequency converting the baseband signal into a millimeter wave signal. Millimeter wave signals refer to radio frequency signals transmitted over the millimeter wave band. Millimeter wave frequency bands include 45 gigahertz (GHz), 60GHz, 77GHz, etc., and millimeter wave frequency bands are generally considered to range from 26.5GHz to 300GHz.

In some implementations, some or all of the functionality of the baseband processing circuit 2011 may also be implemented on a software basis. For example, some or all of the functions of the baseband processing circuit 2011 may be implemented by the processor 203, that is, functional modules of the baseband processing circuit 2011 are integrated in the processor 203, and the internal hardware structure of the communication device 20 is not limited in the embodiments of the present application.

Optionally, the types of control interfaces and data interfaces in the baseband processing circuit and the radio frequency processing circuit include, but are not limited to, a serial peripheral interface (serial peripheral interface, SPI) or a general-purpose input/output (GPIO) interface.

The processor 203 may be a central processing unit (central processing unit, CPU) or an application-specific integrated circuit (ASIC). The processor 203 may be a single-core CPU (single-CPU) processor or a multi-core CPU (multi-CPU) processor. The processor 203 herein may refer to one or more devices, circuits, and/or processing cores for processing data (e.g., computer program instructions).

The memory 204 may be, but is not limited to, read-only memory (ROM) or other type of static storage device that can store static information and instructions, random access memory (random access memory, RAM) or other type of dynamic storage device that can store information and instructions, but may also be electrically erasable programmable read-only memory (EEPROM), compact disc-read only memory (compact disc read-only memory) or other optical disk storage, optical disk storage (including compact disc, laser disc, optical disc, digital versatile disc, blu-ray disc, etc.), magnetic disk or other magnetic storage device, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer. The memory 204 may be stand alone and be coupled to the processor 203 via a communication bus. Or the memory 204 may be integrated with the processor 203.

In the present embodiment, the memory 204 is configured to store a computer program, where the computer program includes program instructions. The processor 203 is configured to invoke the computer program, generate and/or process the PPDU provided in the embodiments of the present application, and implement the communication method provided in the embodiments of the present application in cooperation with the transceiver 201.

The WLAN protocol specifies that the first field in the preamble of the PPDU is used for AGC adjustment. For example, the first fields in the preambles of 7 PPDUs, non-HT PPDU, HT-MF PPDU, VHT PPDU, HE SU PPDU, HE MU PPDU, HEER SU PPDU and HE-TB PPDU, are all L-STF. The L-STF is 8 microseconds long, i.e., the communication device needs to complete AGC adjustment within 8 microseconds from the beginning of receiving these PPDUs. The field lengths referred to in the embodiments of the present application all refer to the length of the field in the time domain, and are units of time, such as microseconds.

For example, fig. 3 to 9 show the structures of the above 7 PPDUs defined in the WLAN protocol. Among them, FIG. 3 is a schematic diagram of the structure of a Non-HT PPDU. Fig. 4 is a schematic diagram of the structure of an HT-MF PPDU. Fig. 5 is a schematic diagram of the structure of a VHT PPDU. Fig. 6 is a schematic diagram of the structure of the HE SU PPDU. Fig. 7 is a schematic diagram of the structure of the HE MU PPDU. Fig. 8 is a schematic diagram of the structure of the HE ER SU PPDU. Fig. 9 is a schematic diagram of the structure of the HE-TB PPDU. As shown in any one of fig. 3 to 9, the PPDU includes a preamble and a data field (data field). As shown in any one of fig. 6 to 9, the PPDU further includes a Packet Extension (PE) field located after the data field.

As shown in fig. 3, the preamble of the Non-HT PPDU includes an L-STF (length of 8 microseconds), an L-LTF (length of 8 microseconds), and an L-SIG field (length of 4 microseconds).

As shown in fig. 4, the preamble of the HT-MF PPDU includes an L-STF (length of 8 microseconds), an L-LTF (length of 8 microseconds), an L-SIG field (length of 4 microseconds), a High Throughput (HT) signal field (HT-SIG field) (length of 8 microseconds), a high throughput short training field (HT-STF) (length of 4 microseconds), and one or more high throughput long training fields (HT-LTFs) (length of 4 microseconds).

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Ext> asext> shownext> inext> fig.ext> 7ext>,ext> theext> preambleext> ofext> theext> HEext> MUext> PPDUext> includesext> anext> Lext> -ext> STFext> (ext> lengthext> ofext> 8ext> microsecondsext>)ext>,ext> anext> Lext> -ext> LTFext> (ext> lengthext> ofext> 8ext> microsecondsext>)ext>,ext> anext> Lext> -ext> SIGext> fieldext> (ext> lengthext> ofext> 4ext> microsecondsext>)ext>,ext> anext> RLext> -ext> SIGext> fieldext> (ext> lengthext> ofext> 4ext> microsecondsext>)ext>,ext> anext> HEext> -ext> SIGext> -ext> aext> fieldext> (ext> lengthext> ofext> 8ext> microsecondsext>)ext>,ext> anext> HEext> -ext> SIGext> -ext> bext> fieldext> (ext> lengthext> ofext> 8ext> microsecondsext>)ext>,ext> anext> HEext> -ext> STFext> (ext> lengthext> ofext> 4ext> microsecondsext>)ext>,ext> andext> oneext> orext> moreext> HEext> -ext> LTFsext> (ext> lengthext> ofext> 4ext> microsecondsext>)ext>.ext>

Ext> asext> shownext> inext> fig.ext> 8ext>,ext> theext> preambleext> ofext> theext> HEext> ERext> SUext> PPDUext> includesext> anext> Lext> -ext> STFext> (ext> lengthext> ofext> 8ext> microsecondsext>)ext>,ext> anext> Lext> -ext> LTFext> (ext> lengthext> ofext> 8ext> microsecondsext>)ext>,ext> anext> Lext> -ext> SIGext> fieldext> (ext> lengthext> ofext> 4ext> microsecondsext>)ext>,ext> anext> RLext> -ext> SIGext> fieldext> (ext> lengthext> ofext> 4ext> microsecondsext>)ext>,ext> anext> HEext> -ext> SIGext> -ext> aext> fieldext> (ext> lengthext> ofext> 16ext> microsecondsext>)ext>,ext> anext> HEext> -ext> STFext> (ext> lengthext> ofext> 4ext> microsecondsext>)ext>,ext> andext> oneext> orext> moreext> HEext> -ext> LTFsext> (ext> lengthext> ofext> 4ext> microsecondsext>)ext>.ext> Ext>ext> theext>ext> preambleext>ext> ofext>ext> theext>ext> HEERext>ext> SUext>ext> PPDUext>ext> isext>ext> differentext>ext> fromext>ext> theext>ext> preambleext>ext> ofext>ext> theext>ext> HEext>ext> SUext>ext> PPDUext>ext> inext>ext> thatext>ext> theext>ext> lengthext>ext> ofext>ext> theext>ext> HEext>ext> -ext>ext> SIGext>ext> -ext>ext> Aext>ext> fieldext>ext> inext>ext> theext>ext> preambleext>ext> ofext>ext> theext>ext> HEext>ext> SUext>ext> PPDUext>ext> isext>ext> 8ext>ext> microsecondsext>ext> andext>ext> theext>ext> lengthext>ext> ofext>ext> theext>ext> HEext>ext> -ext>ext> SIGext>ext> -ext>ext> Aext>ext> fieldext>ext> inext>ext> theext>ext> preambleext>ext> ofext>ext> theext>ext> HEext>ext> ERext>ext> SUext>ext> PPDUext>ext> isext>ext> 16ext>ext> microsecondsext>ext>.ext>ext>

Ext> asext> shownext> inext> fig.ext> 9ext>,ext> theext> preambleext> ofext> theext> HEext> -ext> TBext> PPDUext> includesext> anext> Lext> -ext> STFext> (ext> lengthext> ofext> 8ext> microsecondsext>)ext>,ext> anext> Lext> -ext> LTFext> (ext> lengthext> ofext> 8ext> microsecondsext>)ext>,ext> anext> Lext> -ext> SIGext> fieldext> (ext> lengthext> ofext> 4ext> microsecondsext>)ext>,ext> anext> RLext> -ext> SIGext> fieldext> (ext> lengthext> ofext> 4ext> microsecondsext>)ext>,ext> anext> HEext> -ext> SIGext> -ext> aext> fieldext> (ext> lengthext> ofext> 8ext> microsecondsext>)ext>,ext> anext> HEext> -ext> STFext> (ext> lengthext> ofext> 8ext> microsecondsext>)ext>,ext> andext> oneext> orext> moreext> HEext> -ext> LTFsext> (ext> lengthext> ofext> 4ext> microsecondsext>)ext>.ext> The preamble of the HE-TB PPDU is different from that of the HE SU PPDU in that the length of the HE-STF in the preamble of the HE SU PPDU is 4 microseconds and the length of the HE-STF in the preamble of the HE-TB PPDU is 8 microseconds.

In some cases, however, the communication device may not be able to complete AGC adjustments within 8 microseconds when receiving the PPDU, which may affect normal communications in the WLAN. For example, millimeter wave based WLAN (WLAN over millimeter wave) systems still employ WLAN protocols for communications, while radio frequency chips employed by communication devices operate in the millimeter wave band, i.e., communication devices employ millimeter wave radio frequency chips. The communication equipment in the WLAN system based on millimeter waves is difficult to control the AGC adjustment process within 8 microseconds specified by the WLAN protocol due to the problems of interface speed, interface adaptation, hardware cost and the like of the conventional millimeter wave radio frequency chip, so that the WLAN system cannot normally communicate.

Based on this, embodiments of the present application provide a PPDU, a preamble of which includes a start field and an L-LTF immediately following the start field. The start field is greater than 8 microseconds in length and has a continuous 8 microsecond content that is the same as the content of the L-STF. Optionally, the start field is used for AGC adjustment.

In the embodiment of the application, the traditional short training field is replaced by a start field in the preamble of the PPDU. The start field includes the contents of the conventional short training field to facilitate compatibility. And the starting field is longer than the traditional short training field, so that the time constraint that a receiver utilizes the field to complete corresponding functions (such as synchronization, signal detection, AGC and the like) is relaxed, and the time requirements of hardware with different performances for executing the functions of synchronization, signal detection, AGC and the like can be met, thereby improving the communication reliability of the WLAN in different application scenes. The method only needs to change the first field in the preamble, and has no influence on the subsequent fields, so that the subsequent processing of the PPDU by the communication equipment cannot be changed, and the method is simple to realize.

Alternatively, the start field may be defined as one field, or may be defined as a field combination composed of a plurality of fields. For example, the preamble of the PPDU includes a start field and an L-LTF immediately after the start field. The start field is greater than 8 microseconds in length and has a continuous 8 microsecond content that is the same as the content of the L-STF. In other words, the preamble of the PPDU includes a target field, an L-STF, and an L-LTF. The target field is the other content in the start field than the same continuous 8 microsecond content as the content of the L-STF. The target domain is adjacent to the L-STF, and the target domain and the L-STF precede the L-LTF. The length of the target field is greater than 0. Accordingly, the target domain and the L-STF are used together for automatic gain control adjustment. The length and content of the target domain may be specified by the protocol or may be custom. The length and specific content of the target domain are not limited in the embodiment of the application. The target domain may be named, for example, a private training domain (private training field, PTF).

Optionally, the first 8 microseconds of the content in the start field is the same as the content of the L-STF and/or the last 8 microseconds of the content in the start field is the same as the content of the L-STF. In other words, the start field is composed of an L-STF and a target field, which is before the L-STF or which is after the L-STF. Nor does the embodiments of the present application exclude the case that the middle 8 microsecond content of the start field is identical to the content of the L-STF.

In one implementation, the target field precedes the L-STF, i.e., the target field is the first field in the preamble of the PPDU. In this implementation, the preamble of the PPDU includes a target field, an L-STF, and an L-LTF in order from left to right. The target domain is also used for signal detection. For example, fig. 10 is a schematic structural diagram of a PPDU provided in an embodiment of the present application. As shown in fig. 10, the PPDU includes a preamble and a data field. The preamble includes, in order, a target domain, L-STF, L-LTF, and L-SIG. Wherein the length of the target field is greater than 0, and accordingly, the length of the start field consisting of the target field and the L-STF is greater than 8 microseconds. Optionally, the PPDU further includes a PE domain located after the data domain.

In another implementation, the target domain follows the L-STF, i.e., the target domain is located between the L-STF and the L-LTF. In this implementation, the preamble of the PPDU includes, in order from left to right, an L-STF, a target field, and an L-LTF. For example, fig. 11 is a schematic structural diagram of another PPDU according to an embodiment of the present application. As shown in fig. 11, the PPDU includes a preamble and a data field. The preamble includes, in order, an L-STF, a target domain, an L-LTF, and an L-SIG. Wherein the length of the target field is greater than 0, and accordingly, the length of the start field consisting of the target field and the L-STF is greater than 8 microseconds. Optionally, the PPDU further includes a PE domain located after the data domain.

In the PPDU provided in the embodiment of the present application, the start field of the preamble of the PPDU has a content of 8 consecutive microseconds that is the same as the content of the L-STF, that is, the start field has a content of the L-STF. The embodiment of the application does not limit the length and the specific content of the content except the continuous 8 microsecond content which is the same as the content of the L-STF in the starting field, and can be specified by a protocol or negotiated and determined by two communication parties. Optionally, the other content in the start field than the same continuous 8 microsecond content as the content of the L-STF includes part or all of one or more fields including, but not limited to, L-STF, L-LTF, L-SIG domain, HE-STF, or HE-LTF. That is, the start field may be composed of a plurality of L-STFs, or of M L-STFs and N L-LTFs, or of P L-STFs and Q L-SIG domains, or of X L-STFs, Y L-LTFs and Z L-SIG domains, and so on. M, N, P, Q, X, Y, Z are positive numbers and M, P and X are each greater than or equal to 1.

Optionally, the length of the start field is variable, i.e. the length of the above-mentioned target field is variable.

Optionally, the other content in the start field than the same continuous 8 microsecond content as the content of the L-STF includes one or more of: at least 6L-STFs, at least 6L-LTFs, at least 12L-SIG domains, or a combination of at least 3L-STFs and at least 3L-LTFs. In these examples, the start field is no less than 56 microseconds in length. For example, the start field has a length of 56 microseconds, 60 microseconds, 64 microseconds, 80 microseconds, or the like.

For example, the start field may have a length of 56 microseconds, and the other contents than the continuous 8-microsecond content identical to the contents of the L-STF may include 6L-STF contents, or 6L-LTF contents, or 12L-SIG fields, or a combination of 3L-STF contents and 3L-LTF contents. For example, fig. 12 to 15 are schematic diagrams of a start field according to an embodiment of the present application. As shown in fig. 12, the start field includes 7 consecutive L-STFs. As shown in fig. 13, the start field includes 6 consecutive L-LTFs and 1L-STF. As shown in fig. 14, the start field includes 12 consecutive L-SIG fields and 1L-STF. As shown in fig. 15, the start field includes 3 consecutive L-LTFs and 4L-STFs.

For another example, the start field may have a length of 88 microseconds, and the other contents of the start field than the contents of one L-STF (the continuous 8 microsecond contents described above) may include 10L-STFs, or 10L-LTFs, or 20L-SIG fields, or a combination of 5L-STFs and 5L-LTFs.

Alternatively, the start field may be greater than 8 microseconds and less than 56 microseconds in length. For example, the start field has a length of 24 microseconds, 32 microseconds, 40 microseconds, 48 microseconds, or the like.

For example, the start field may have a length of 24 microseconds, and may include 2L-STFs, or 2L-LTFs, or 4L-SIG fields, or a combination of 1L-STF and 1L-LTF.

The length and the components of the content other than the content of one L-STF in the start field (the above-mentioned continuous 8 microsecond content) are not limited in this embodiment, and any conceivable scheme is within the scope of protection of this application, for example, the content other than the content of one L-STF in the start field (the above-mentioned continuous 8 microsecond content) may include 2 to 10L-STFs, which is not illustrated here.

Optionally, the continuous 8 microsecond content in the beginning field of the preamble of the PPDU provided in the embodiment of the present application, which is the same as the content of the L-STF, and the content located after the beginning field in the PPDU form a Non-HT PPDU (as shown in fig. 3), an HT-MF PPDU (as shown in fig. 4), a VHT PPDU (as shown in fig. 5), an HE SU PPDU (as shown in fig. 6), an HE MU PPDU (as shown in fig. 7), an HE ER SU PPDU (as shown in fig. 8), or an HE-TB PPDU (as shown in fig. 9). It may also be understood that the PPDU provided in the embodiment of the present application is obtained by adding the destination domain on the basis of the PPDU shown in any one of fig. 3 to fig. 9.

Fig. 16 is a flowchart of a communication method in a WLAN according to an embodiment of the present application. The first communication device and the second communication device are both communication devices in the WLAN. The method can be applied, for example, in an application scenario as shown in fig. 1. As shown in fig. 16, the method includes:

in step 1601, the first communication device generates a PPDU, where a preamble of the PPDU includes a start field and an L-LTF immediately after the start field, the start field has a length greater than 8 microseconds, and a continuous 8-microsecond content in the start field is identical to a content of the L-STF.

The PPDU structure may refer to the related descriptions in the above embodiments, and the embodiments of the present application are not repeated herein. The PPDU may be, for example, a PPDU as shown in fig. 10 or 11.

Step 1602, the first communication device transmits the PPDU to the second communication device.

Optionally, the first communication device transmits the PPDU to the second communication device over the millimeter wave band. Accordingly, the second communication device receives the PPDU from the first communication device over the millimeter wave band.

In step 1603, the second communication device performs automatic gain control adjustment on the received signal power of the PPDU according to the length of the start field in the PPDU.

Step 1603, namely, the second communication device performs automatic gain control adjustment on the received signal power of the PPDU in the receiving duration of the start field of the PPDU. And after finishing automatic gain control adjustment on the received signal power of the PPDU, the second communication equipment continuously receives the residual content of the PPDU and analyzes and processes the PPDU according to the WLAN protocol.

In the communication method provided in the embodiment of the present application, the first communication device replaces the conventional short training field with the start field in the preamble of the PPDU transmitted to the second communication device. The start field includes the contents of the conventional short training field to facilitate compatibility. And the start field is longer than the traditional short training field, so that the time constraint of using the field to complete corresponding functions (such as synchronization, signal detection, AGC and the like) of the second communication equipment is relaxed, and the time requirements of executing the functions of synchronization, signal detection, AGC and the like by hardware with different performances can be met, thereby improving the communication reliability of the WLAN in different application scenes. The embodiment of the application only needs to change the first field in the preamble, and has no influence on the subsequent field, so that the second communication equipment does not need to make any change on the subsequent processing of the PPDU except for increasing the time for completing the corresponding function by using the field, and the implementation is simple.

Fig. 17 and fig. 18 are schematic structural diagrams of a communication device in a WLAN according to an embodiment of the present application. The modules shown in fig. 17 and 18 may also be integrated in a communication device.

As shown in fig. 17, the communication apparatus 1700 includes: a generation module 1701 and a transmission module 1702. A generating module 1701, configured to generate a PPDU, where a preamble of the PPDU includes a start field and an L-LTF immediately after the start field, the start field has a length greater than 8 microseconds, and a continuous 8 microsecond content in the start field is the same as a content of the L-STF. A transmitting module 1702 configured to transmit a PPDU to another communication device in the WLAN.

As shown in fig. 18, the communication device 1800 includes: a receiving module 1801 and an AGC adjustment module 1802. A receiving module 1801, configured to receive a PPDU from another communication device in the WLAN, where a preamble of the PPDU includes a start field and an L-LTF immediately after the start field, the start field has a length greater than 8 microseconds, and a continuous 8-microsecond content in the start field is the same as a content of the L-STF. And an AGC adjustment module 1802, configured to perform automatic gain control adjustment on the received signal power of the PPDU according to the length of the start field.

Optionally, a start field is used for automatic gain control adjustment.

Optionally, the other content in the start field than the same continuous 8 microsecond content as the content of the L-STF includes part or all of one or more fields including the L-STF, L-LTF, L-SIG field, HE-STF, or HE-LTF.

Alternatively, in the communication device shown in fig. 17, a transmitting module 1702 is configured to transmit a PPDU to another communication device in the millimeter wave band. In the communication device shown in fig. 18, a receiving module 1801 is configured to receive a PPDU from another communication device in the millimeter wave band.

Optionally, the length of the start field is predefined or determined by both parties of the communication device.

The specific manner in which the various modules perform the operations in the apparatus of the above embodiments have been described in detail in connection with the embodiments of the method, and will not be described in detail herein.

The embodiment of the application also provides a communication device in the WLAN, which comprises: a transceiver and an antenna. The transceiver is configured to transmit and receive PPDUs with an antenna. The preamble of the PPDU includes a start field and an L-LTF immediately after the start field. The start field is greater than 8 microseconds in length and has a continuous 8 microsecond content that is the same as the content of the L-STF.

Optionally, the transceiver comprises a millimeter wave radio frequency chip.

For example, the communication device may be a communication device as shown in fig. 2.

The embodiment of the application also provides a WLAN, which comprises the following steps: a first communication device and a second communication device. The first communication device is configured to transmit a PPDU to the second communication device, wherein a preamble of the PPDU includes a start field and an L-LTF immediately after the start field, the start field has a length of more than 8 microseconds, and a content of 8 consecutive microseconds is identical to a content of the L-STF in the start field. The second communication device is configured to perform automatic gain control adjustment on the received signal power of the PPDU according to the length of the start field.

It will be understood by those skilled in the art that all or part of the steps for implementing the above embodiments may be implemented by hardware, or may be implemented by a program for instructing relevant hardware, where the program may be stored in a computer readable storage medium, and the storage medium may be a read-only memory, a magnetic disk or an optical disk, etc.

In the present embodiments, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

The term "and/or" in this application is merely an association relation describing an associated object, and indicates that three relations may exist, for example, a and/or B may indicate: a exists alone, A and B exist together, and B exists alone. In addition, the character "/" herein generally indicates that the front and rear associated objects are an "or" relationship.

The foregoing description of the preferred embodiments is merely exemplary in nature and is in no way intended to limit the invention, its application, to the form and details of construction and the arrangement of the preferred embodiments, and thus, any and all modifications, equivalents, and alternatives falling within the spirit and principles of the present application.

Claims

1. A method of communication in a wireless local area network, WLAN, the method comprising:

A first communication device in the WLAN transmits a physical layer protocol data unit, PPDU, to a second communication device in the WLAN, the preamble of the PPDU including a start field and a legacy long training field, L-LTF, immediately after the start field, the start field being greater than 8 microseconds in length, and there being a continuous 8 microsecond content in the start field that is the same as the content of the legacy short training field, L-STF.

2. The method of claim 1, wherein the first 8 microseconds of content in the start field is the same as the content of the L-STF and/or the last 8 microseconds of content in the start field is the same as the content of the L-STF.

3. The method according to claim 1 or 2, characterized in that the start field is used for automatic gain control adjustment.

4. A method according to any one of claims 1 to 3, characterized in that the other content of the start field than the continuous 8 microsecond content comprises part or all of one or more fields including L-STF, L-LTF, legacy signal L-SIG field, high efficiency short training field HE-STF or high efficiency long training field HE-LTF.

5. The method of any of claims 1 to 4, wherein the content in the start field other than the continuous 8 microsecond content comprises one or more of: at least 6L-STFs, at least 6L-LTFs, at least 12L-SIG domains, or a combination of at least 3L-STFs and at least 3L-LTFs.

6. The method according to any of claims 1 to 5, wherein the first communication device in the WLAN sends a physical layer protocol data unit, PPDU, to the second communication device in the WLAN, comprising:

the first communication device transmits the PPDU to the second communication device over a millimeter wave band.

7. The method according to any of claims 1 to 6, wherein the length of the start field is predefined or determined by negotiation of the first communication device and the second communication device.

8. The method of any of claims 1-7, wherein the continuous 8 microsecond content and content in the PPDU located after the start field constitute a Non-high throughput Non-HT PPDU, a high throughput mixed format HT-MF PPDU, a very high throughput VHT PPDU, a high efficiency single user HE SU PPDU, a high efficiency multi-user HE MU PPDU, a high efficiency extended distance single user HE ER SU PPDU, or a high efficiency triggered HE-TB PPDU.

9. A communication device in a wireless local area network, WLAN, the communication device comprising:

a generating module, configured to generate a physical layer protocol data unit PPDU, where a preamble of the PPDU includes a start field and a legacy long training field L-LTF immediately after the start field, the length of the start field is greater than 8 microseconds, and a content of continuous 8 microseconds in the start field is the same as a content of a legacy short training field L-STF;

And the sending module is used for sending the PPDU to another communication device in the WLAN.

10. A communication device according to claim 9, characterized in that the first 8 microseconds of content in the start field is identical to the content of the L-STF and/or the last 8 microseconds of content in the start field is identical to the content of the L-STF.

11. A communication device according to claim 9 or 10, characterized in that the start field is used for automatic gain control adjustment.

12. The communication device of any of claims 9 to 11, wherein the content of the start field other than the continuous 8 microsecond content includes part or all of one or more fields including an L-STF, an L-LTF, a legacy signal L-SIG field, a high-efficiency short training field HE-STF, or a high-efficiency long training field HE-LTF.

13. The communication device of any of claims 9 to 12, wherein the other content in the start field than the continuous 8 microsecond content includes one or more of: at least 6L-STFs, at least 6L-LTFs, at least 12L-SIG domains, or a combination of at least 3L-STFs and at least 3L-LTFs.

14. A communication device according to any one of claims 9 to 13, characterized in that,

and the sending module is used for sending the PPDU to the other communication equipment on the millimeter wave frequency band.

15. A communication device according to any of claims 9 to 14, wherein the length of the start field is predefined or determined by negotiation of the first communication device and the second communication device.

16. The communication device of any of claims 9 to 15, wherein the contiguous 8 microsecond content and content in the PPDU located after the start field constitute a Non-high throughput Non-HT PPDU, a high throughput mixed format HT-MF PPDU, a very high throughput VHT PPDU, a high efficiency single user HE SU PPDU, a high efficiency multi-user HE MU PPDU, a high efficiency extended distance single user HE ER SU PPDU, or a high efficiency triggered HE-TB PPDU.

17. A communication device in a wireless local area network, WLAN, comprising: a transceiver and an antenna;

the transceiver is configured to transmit and receive a physical layer protocol data unit PPDU with the antenna, a preamble of the PPDU includes a start field and a legacy long training field L-LTF immediately after the start field, the start field has a length of greater than 8 microseconds, and a continuous 8-microsecond content in the start field is identical to a content of a legacy short training field L-STF.

18. The communication device of claim 17, wherein the transceiver comprises a millimeter wave radio frequency chip.