CN111245763A

CN111245763A - Data transmitting and receiving method for multi-AP operation of OFDM system, access point, site and storage medium

Info

Publication number: CN111245763A
Application number: CN202010026811.4A
Authority: CN
Inventors: 赵育仁; 余庆华; 徐彦超
Original assignee: Spreadtrum Communications Shanghai Co Ltd
Current assignee: Spreadtrum Communications Shanghai Co Ltd
Priority date: 2020-01-10
Filing date: 2020-01-10
Publication date: 2020-06-05
Anticipated expiration: 2040-01-10
Also published as: CN111245763B

Abstract

A data sending and receiving method, an access point, a site and a storage medium for multi-AP operation of an OFDM system are provided, wherein the multi-AP comprises n sending ends, n is more than or equal to 2, and the method comprises the following steps: for each sending end, responding to the received trigger frame, determining a sending mode, wherein the sending configurations of different sending ends are different; the n sending ends respectively adopt corresponding sending configurations to send the data; wherein, the transmission modes adopted by the n transmitting ends are selected from: the method comprises a DCM transmission mode, an STBC transmission mode and a transmission mode combining the DCM transmission mode and the STBC transmission mode, wherein each transmission mode comprises a plurality of transmission configurations. The scheme provided by the invention can optimize the multi-AP joint transmission mechanism of the OFDM system, has better diversity gain when data transmission is carried out in a multi-AP operating system, and improves the transmission reliability.

Description

Data transmitting and receiving method for multi-AP operation of OFDM system, access point, site and storage medium

Technical Field

The invention relates to the technical field of wireless communication, in particular to a data transmitting and receiving method, an access point, a station and a storage medium for multi-AP operation of an OFDM system.

Background

In the protocol of the wireless local area network, a joint function of a plurality of Access points (APs for short) is discussed, and a trigger frame is sent between the APs to achieve synchronization of data sending and/or start a data sending process. For example, for the access point AP1 (which may be regarded as the current access point) and the access point AP2 (which may be regarded as the cooperative access point), the access point AP1 and the access point AP2 are triggered to synchronously transmit data to a Station (STA) by the Station transmitting a trigger frame to the access point AP2 through the access point AP1 or transmitting a trigger frame to the access point AP1 and the access point AP 2.

The better performance of the multi-AP operating system is beam forming, but this method requires channel estimation, channel feedback and strict time synchronization requirements, and is difficult to achieve in a system without closed-loop time synchronization calibration. Another implementation manner of the AP operating system is to improve diversity gain, and when the existing multi-AP operating system performs data transmission, the diversity gain is not ideal, which affects transmission reliability.

Disclosure of Invention

The invention solves the technical problem of how to improve the diversity gain of the OFDM system during multi-AP operation and optimize the data transmission reliability.

In order to solve the above technical problem, an embodiment of the present invention provides a data sending method for multi-AP operation in an OFDM system, where the multi-AP includes n sending ends, n is greater than or equal to 2, and the data sending method includes: for each sending end, responding to the received trigger frame, determining a sending mode, wherein the sending configurations of different sending ends are different; the n sending ends respectively adopt corresponding sending configurations to send the data; wherein, the transmission modes adopted by the n transmitting ends are selected from: the method comprises a DCM transmission mode, an STBC transmission mode and a transmission mode combining the DCM transmission mode and the STBC transmission mode, wherein each transmission mode comprises a plurality of transmission configurations.

Optionally, the n transmitting ends are associated with a channel, where the channel includes multiple subcarriers, and the multiple subcarriers include a first group of subcarriers and a second group of subcarriers that are disjoint; the DCM transmission scheme is a scheme for transmitting the same data through the first group of subcarriers and/or the second group of subcarriers, respectively.

Optionally, the subcarriers in the first group of subcarriers and the subcarriers in the second group of subcarriers form subcarrier pairs pairwise, and data sent by each subcarrier pair is the same.

Optionally, the n sending ends include a first sending end, a second sending end, a third sending end and a fourth sending end, and the sending of the data by the n sending ends respectively using the corresponding sending configurations includes: the first sending end sends the data through the first group of subcarriers, and the data is a first STS in an STBC format; the second transmitting end transmits the data through the second group of subcarriers, and the data is a first kind of STS in STBC format; the third transmitting end transmits the data through the first group of subcarriers, and the data is a second kind of STS in STBC format; and the fourth transmitting end transmits the data through the second group of subcarriers, and the data is a second kind of STS in STBC format.

Optionally, the n sending ends include a first sending end, a second sending end, and a third sending end, and the sending of the data by the n sending ends respectively using the corresponding sending configurations includes: the first sending end sends the data through the first group of subcarriers, and the data is a first STS in an STBC format; the second transmitting end transmits the data through the second group of subcarriers, and the data is a first kind of STS in STBC format; and the third transmitting end respectively transmits the data through the first group of subcarriers and the second group of subcarriers, and the data is a second kind of STS in STBC format.

Optionally, the n sending ends include a first sending end, a second sending end, and a third sending end, and the sending of the data by the n sending ends respectively using the corresponding sending configurations includes: the first transmitting end transmits the data through the first group of subcarriers and the second group of subcarriers respectively, and the data is a first kind of STS in an STBC format; the second transmitting end transmits the data through the first group of subcarriers, and the data is a second kind of STS in STBC format; and the third transmitting end transmits the data through the second group of subcarriers, and the data is a second kind of STS in STBC format.

Optionally, the n sending ends include a first sending end and a second sending end, and the sending of the data by the n sending ends respectively using the corresponding sending configurations includes: the first transmitting end transmits the data through the first group of subcarriers and the second group of subcarriers respectively, and the data is a first kind of STS in an STBC format; and the second transmitting end respectively transmits the data through the first group of subcarriers and the second group of subcarriers, and the data is a second kind of STS in an STBC format.

Optionally, the n sending ends include a first sending end and a second sending end, and the sending of the data by the n sending ends respectively using the corresponding sending configurations includes: the first sending end sends the data through the first group of subcarriers; and the second sending end sends the data through the second group of subcarriers.

Optionally, the n sending ends include a first sending end and a second sending end, and the sending of the data by the n sending ends respectively using the corresponding sending configurations includes: the first sending end sends the data, and the data is a first STS in an STBC format; and the second sending end sends the data, and the data is a second STS in an STBC format.

Optionally, the n transmitting ends further include a cyclic shift diversity transmitting end, and the transmitting the data by the n transmitting ends respectively using the corresponding transmission configurations further includes: the cyclic shift diversity transmitting end continues to transmit the data using the transmission configuration of any one of the n transmitting ends except the cyclic shift diversity transmitting end, and a data transmission timing of the cyclic shift diversity transmitting end has cyclic shift diversity compared with a data transmission timing of the transmitting end continued to the cyclic shift diversity transmitting end.

Optionally, the multiple APs include a current access point and a cooperative access point, and the current access point transmits the data to the cooperative access point using OOB.

Optionally, the current access point includes i transmitting terminals, and the cooperative access point includes j transmitting terminals, where i is greater than or equal to 1, j is greater than or equal to 1, and i + j is equal to n.

Optionally, the number of the cooperative access points is multiple, and each cooperative access point includes one or more transmitting ends.

An embodiment of the present invention further provides an access point, where the access point includes at least one sending end, and further includes: the determining module is used for responding to the received trigger frame and determining a sending mode for each sending end, wherein the sending configurations of different sending ends are different; the sending module is used for sending the data by the at least one sending end by adopting corresponding sending configuration; wherein, the sending mode adopted by the at least one sending end is selected from: the method comprises a DCM transmission mode, an STBC transmission mode and a transmission mode combining the DCM transmission mode and the STBC transmission mode, wherein each transmission mode comprises a plurality of transmission configurations.

The embodiment of the invention also provides a data receiving method for multi-AP operation of the OFDM system, wherein the multi-AP comprises n sending ends, n is more than or equal to 2, and the data receiving method comprises the following steps: determining whether to receive the data in a multi-AP receiving mode; when the data is determined to be received in a multi-AP receiving mode, receiving the data which is sent by the sending end by adopting corresponding sending configuration, wherein the sending configurations of different sending ends are different; wherein, the transmission modes adopted by the n transmitting ends are selected from: the method comprises a DCM transmission mode, an STBC transmission mode and a transmission mode combining the DCM transmission mode and the STBC transmission mode, wherein each transmission mode comprises a plurality of transmission configurations.

An embodiment of the present invention further provides a station, including: a determining module, configured to determine whether to receive the data in a multi-AP receiving manner; the receiving module is used for receiving the data sent by the sending end by adopting the corresponding sending configuration when the data is determined to be received by adopting a multi-AP receiving mode, wherein the sending configurations of different sending ends are different; wherein, the transmission modes adopted by the n transmitting ends are selected from: the method comprises a DCM transmission mode, an STBC transmission mode and a transmission mode combining the DCM transmission mode and the STBC transmission mode, wherein each transmission mode comprises a plurality of transmission configurations.

The embodiment of the invention also provides a storage medium, wherein computer instructions are stored on the storage medium, and the computer instructions execute the steps of the method when running.

Compared with the prior art, the technical scheme of the embodiment of the invention has the following beneficial effects:

the embodiment of the invention provides a data transmission method for multi-AP operation of an OFDM system, wherein the multi-AP comprises n sending ends, n is more than or equal to 2, and the data transmission method comprises the following steps: for each sending end, responding to the received trigger frame, determining a sending mode, wherein the sending configurations of different sending ends are different; the n sending ends respectively adopt corresponding sending configurations to send the data; wherein, the transmission modes adopted by the n transmitting ends are selected from: the method comprises a DCM transmission mode, an STBC transmission mode and a transmission mode combining the DCM transmission mode and the STBC transmission mode, wherein each transmission mode comprises a plurality of transmission configurations.

Therefore, the scheme of the invention can optimize the multi-AP joint transmission mechanism of the OFDM system, has better diversity gain when data transmission is carried out in the multi-AP operating system of the OFDM system, and improves the transmission reliability. Specifically, the transmission method combining the DCM transmission method and the STBC transmission method can achieve four times of diversity gain, which is beneficial to improving reliability when a station as a receiving end receives data. For example, in a fading channel, a transmission method combining the DCM transmission method and the STBC transmission method can better ensure reliable transmission of data. Further, the DCM transmission method or the STBC transmission method alone can also achieve twice diversity gain. The multi-AP operating system adopting the scheme of this embodiment may flexibly select a transmission mode and a specific transmission configuration according to the number of APs and the number of transmission ends of each AP, so as to take diversity gain and operation flexibility into consideration. The number of the transmitting terminals of each AP may refer to the number of the transmitting terminals allocated to perform the data transmission operation by each AP this time.

Drawings

Fig. 1 is a flowchart of a data transmission method for multi-AP operation of an OFDM system according to an embodiment of the present invention;

FIG. 2 is a diagram illustrating a first exemplary application scenario of an embodiment of the present invention;

FIG. 3 is a timing diagram illustrating data transmission based on a reverse trigger in the application scenario of FIG. 2;

FIG. 4 is a diagram illustrating a second exemplary application scenario of the present invention;

FIG. 5 is a schematic diagram of a third exemplary application scenario of an embodiment of the present invention;

fig. 6 is a schematic structural diagram of an access point according to an embodiment of the present invention;

fig. 7 is a flowchart of a data receiving method for multi-AP operation of an OFDM system according to an embodiment of the present invention;

fig. 8 is a schematic structural diagram of a station according to an embodiment of the present invention.

Detailed Description

As known in the background art, when data transmission is performed in a multi-AP operating system of an existing OFDM system, diversity gain is not ideal, and transmission reliability is affected.

Therefore, the scheme of the invention can optimize the multi-AP joint transmission mechanism of the OFDM system, has better diversity gain when data transmission is carried out in the multi-AP operating system of the OFDM system, and improves the transmission reliability. Specifically, the transmission method combining the DCM transmission method and the STBC transmission method can achieve four times of diversity gain, which is advantageous for improving reliability when a station as a receiver receives data. For example, in a fading channel, a transmission method combining the DCM transmission method and the STBC transmission method can better ensure reliable transmission of data. Further, the DCM transmission method or the STBC transmission method alone can also achieve twice diversity gain. The multi-AP operating system adopting the scheme of this embodiment may flexibly select a transmission mode and a specific transmission configuration according to the number of APs and the number of transmission ends of each AP, so as to take diversity gain and flexibility into consideration. The number of the transmitting terminals of each AP may refer to the number of the transmitting terminals allocated to perform the data transmission operation by each AP this time.

The Multi-AP operation according to the embodiment of the present invention may include a Multi-AP join operation (Multi-AP join operation). The multi-AP joint operation refers to that multiple APs respectively transmit data to the same station.

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below.

Fig. 1 is a flowchart of a data transmission method for multi-AP operation in an OFDM system according to an embodiment of the present invention. Here, OFDM is an abbreviation of Orthogonal Frequency Division Multiplexing (Orthogonal Frequency Division Multiplexing).

The scheme of this embodiment may be executed by each AP, and each AP may execute the scheme of this embodiment synchronously to send the data to the station synchronously.

Specifically, the multiple APs may refer to 2 or more APs. The multiple APs may include n transmitters, where n is greater than or equal to 2, and each AP may include one or more transmitters.

More specifically, referring to fig. 1, the data transmission method for multi-AP operation in the OFDM system according to this embodiment may include the following steps:

step S101, for each sending end, responding to the received trigger frame, determining a sending mode, wherein the sending configuration of different sending ends is different;

step S102, the n sending ends respectively adopt corresponding sending configurations to send the data;

the transmission modes adopted by the n transmission ends may be selected from: a Dual Carrier Modulation (DCM) transmission mode, a Space-Time Block Code (STBC) transmission mode, and a transmission mode combining the DCM transmission mode and the STBC transmission mode, wherein each transmission mode includes multiple transmission configurations.

In one implementation, the APs in the multiple APs may communicate directly with each other, and accordingly, the trigger frame may be transmitted from one AP to the other AP in the multiple APs.

In a variation, the APs in the multiple APs cannot communicate directly with each other, and accordingly, the trigger frame may be sent to the APs by a common station. For example, the multiple APs may include a current access point (which may also be referred to as an initialization access point) and a cooperative access point, and the current access point sends a trigger notification to the common station; and in response to receiving the trigger notification, the public station sends the trigger frame to the current access point and the cooperative access point indicated by the trigger notification to trigger the current access point and the cooperative access point to respectively send the data. Wherein the common station and the current access point may be located in one basic service set, and the cooperative access point and the common station may be located in another basic service set.

It should be noted that the scheme of this embodiment does not limit the transmission manner of the trigger frame.

In one implementation, the step S101 may include: and determining a sending mode and specific sending configuration according to the number of the APs included by the multiple APs and the number of the sending ends of each AP. Thus, both diversity gain and operational flexibility can be achieved.

Specifically, the number of the transmitting ends of each AP may refer to the number of the transmitting ends allocated to perform the data transmission operation by each AP this time.

In one implementation, the n transmitters may be associated with channels. Wherein the channel refers to a communication link between the multiple APs and the station, and the station refers to a receiving end of the data.

In particular, for each channel, the channel may include a plurality of subcarriers, which may include a first set of subcarriers and a second set of subcarriers that are disjoint. Where disjoint refers to the situation where there are no subcarriers in common in the two groups of subcarriers. For example, assuming that a channel includes 48 subcarriers, 24 of the subcarriers may belong to the first group of subcarriers, and the remaining 24 subcarriers may belong to the second group of subcarriers.

Further, the DCM transmission scheme is a scheme for transmitting the same data through the first group of subcarriers and/or the second group of subcarriers of each channel.

Taking 2 APs for transmitting data in DCM as an example, it is assumed that the two APs (denoted as AP1 and AP2) are both 1x1AP, that is, the two APs respectively include 1 transmitter, the channel frequency response between the AP1 and the station serving as the receiver is denoted as H1, and the channel frequency response between the AP2 and the station is denoted as H2. In performing the step S102, the AP1 may transmit the data through a first set of subcarriers and the AP2 may transmit the data through a second set of subcarriers. At this time, the first group of subcarriers and the second group of subcarriers, which transmit the same data, experience a channel frequency response with lower correlation.

Taking an example that a single AP transmits data in a DCM transmission manner, assuming that the AP (denoted as AP1) is 1x1AP, that is, the AP1 and the station respectively include 1 transmitter, the channel frequency response is denoted as H1. In performing step S102, the AP1 may transmit the data over a first set of subcarriers and repeatedly transmit the data over a second set of subcarriers. At this time, the channel frequency responses experienced by the first group of subcarriers and the second group of subcarriers transmitting the same data belong to the same channel frequency response H1.

Therefore, the DCM transmission mode repeatedly transmits the same data on different frequency domains, so that the receiving reliability of a receiving end is improved, and the diversity gain is better.

Further, when data transmission is performed by using the DCM sending method, a single subcarrier may carry a Modulation manner with 2 times of bit (bit) number to compensate for the effect of halving the number of data transmission subcarriers, for example, Binary Phase Shift Keying (BPSK) or Quadrature Phase Shift Keying (QPSK) is used in non-DCM Modulation, and QPSK or Quadrature Amplitude Modulation 16 (16-QAM) is correspondingly used in DCM Modulation.

In one implementation, the subcarriers in the first set of subcarriers and the subcarriers in the second set of subcarriers form pairs of subcarriers, and data transmitted by each pair of subcarriers is the same.

In one implementation, the frequency domain range occupied by the first set of subcarriers and the frequency domain range occupied by the second set of subcarriers may be non-overlapping. For example, if the channel includes the 0 th subcarrier, the 1 st subcarrier, and the 47 th subcarrier in order from small to large in the frequency domain, the first group of subcarriers may include the 0 th subcarrier to the 23 rd subcarrier, and the second group of subcarriers may include the 24 th subcarrier to the 47 th subcarrier. At this time, the two groups of subcarriers are far apart in the frequency domain, which is beneficial to reducing interference when the synchronization among multiple APs is poor, and improving the reliability of the station in receiving data.

In a variation, the frequency domain range occupied by the first set of subcarriers may overlap with the frequency domain range occupied by the second set of subcarriers. For example, assuming that the channel includes the 0 th subcarrier, the 1 st subcarrier, and the 47 th subcarrier in order from small to large in the frequency domain, the first group of subcarriers may include subcarriers with a single number therein, and the second group of subcarriers may include subcarriers with a double number therein. In this case, since the first group of subcarriers and the second group of subcarriers both use substantially the entire frequency band of the channel, the effect is better as a whole.

In one implementation, the n transmitting ends may include a first transmitting end, a second transmitting end, a third transmitting end, and a fourth transmitting end.

Accordingly, in step S102, the first transmitting end transmits the data through the first group of subcarriers, and the data is a first STS in STBC format.

And the second transmitting end transmits the data through the second group of subcarriers, and the data is a first kind of STS in an STBC format.

And the third transmitting end transmits the data through the first group of subcarriers, and the data is a second kind of STS in STBC format.

And the fourth transmitting end transmits the data through the second group of subcarriers, and the data is a second kind of STS in STBC format.

Further, the first sending end, the second sending end, the third sending end and the fourth sending end may send the data in a synchronous manner.

The scheme of this embodiment may be applied to a scenario with 4 APs, where each AP includes 1 transmitting end. Or, the scheme of this embodiment may be applied to a scenario with 2 APs, where each AP includes 2 transmitting ends. Or, this embodiment may be applicable to a scenario with 2 APs, where 1AP includes 1 transmitting end, and the other 1AP includes 3 transmitting ends. Or, the scheme of this embodiment may be applicable to a scenario with 3 APs, where 2 APs include 1 transmitting end, and 1AP includes 2 transmitting ends.

For example, referring to fig. 2, fig. 2 is a schematic diagram of a first exemplary application scenario of the embodiment of the present invention. The application scenario is specifically described by taking 4 APs (denoted as AP1, AP2, AP3, and AP4) as an example, where each AP includes 1 sender.

In response to receiving the trigger frame, AP1, AP2, AP3, and AP4 respectively transmit data to the station (denoted by STA in the figure). The channel frequency response between the AP1 and the station STA is denoted as H1, the channel frequency response between the AP2 and the station STA is denoted as H2, the channel frequency response between the AP3 and the station STA is denoted as H3, and the channel frequency response between the AP4 and the station STA is denoted as H4.

Specifically, the AP1 may transmit the data over a first set of subcarriers (denoted as @ DCM1 tones), and the data is a first STS (denoted as STS0) in STBC format. Assume STS 0: { S1, S2, S3, S4. }, where S is an OFDM symbol (OFDM symbol).

The AP2 may send the data over a first set of subcarriers (denoted as @ DCM1 tones) and the data is a second STS (denoted as STS1) in STBC format. Assume STS 1: -S2, S1, -S4, S3, wherein S is an OFDM symbol (OFDM symbol).

The AP3 may send the data over a second set of subcarriers (denoted as @ DCM2 tones), and the data is a first STS (denoted as STS0) in STBC format.

The AP4 may send the data over a second set of subcarriers (denoted as @ DCM2 tones), and the data is a second STS (denoted as STS1) in STBC format.

For a station STA, in the present application scenario, the station STA may receive data streams { H1S1-H2S2, H1S2+ H2S1, H1S3-H2S4, H1S4+ H2S3 } through a channel frequency response of the first group of subcarriers @ DCM1 tones, and may also receive data streams { H3S1-H4S2, H3S2+ H4S1, H3S3-H4S4, H3S4+ H4S3 } through a channel frequency response of the second group of subcarriers @ DCM2 tones. The data can be obtained by joint demodulation of STBC + DCM for the two data streams.

With reference to fig. 2 and fig. 3, fig. 3 is a timing diagram of data transmission based on a reverse trigger in the application scenario shown in fig. 2. Specifically, in conjunction with fig. 2 and 3, the AP1 sends a trigger notification within the time range T1. The trigger notification includes the start time and the end time of sending the trigger frame, i.e., the start time and the end time of the time range T2.

In response to receiving the trigger notification, the common station STA transmits the trigger frame within a time range T2.

Before the data transmission starts, the AP1 transmits data to be transmitted to the AP2, the AP3, and the AP4 using OOB.

In response to receiving the trigger frame, the AP1, AP2, AP3, and AP4 each send the data within a time range T3. The start time of the time range T3 may have a preset time offset from the trigger frame, where the start time of the time range T3 is the time when the data transmission is started. When the AP1, the AP2, the AP3, and the AP4 perform the multi-AP cooperative operation, the transmission timings at which the APs transmit data are completely synchronized, and the end timings at which the APs end the transmission are also completely synchronized.

Specifically, the AP1 may transmit the data over a first set of subcarriers (denoted as @ DCM1 tones) within a time range T3, and the data is an STS0 in STBC format.

The AP2 may send the data over a first set of subcarriers (denoted as @ DCM1 tones) within a time range T3, and the data is an STS1 in STBC format.

The AP3 may send the data over a second set of subcarriers (denoted as @ DCM2 tones) within time range T3, and the data is an STS0 in STBC format.

The AP3 may send the data over a second set of subcarriers (denoted as @ DCM2 tones) within time range T3, and the data is an STS1 in STBC format.

It should be noted that the transmission start time of the data may coincide with the start time of the time range T3.

After receiving the data, the STA may send an Acknowledgement (ACK).

In response to receiving the trigger notification or the trigger frame, the other nearby APs and STA may set up a Network Allocation Vector (NAV) so that the other nearby APs and STA do not transceive data within the time range T4.

Specifically, the time interval between the time range T1, the time range T2, and the time range T3 may be a Short Space Inter Frame (SIFS). As to the specific length of SIFS, reference may be made to the prior art, and the embodiment of the present invention is not limited thereto.

For another example, referring to fig. 4, fig. 4 is a schematic diagram of a second exemplary application scenario of the embodiment of the present invention. The application scenario takes 4 transmitting terminals of 3 APs (denoted as AP1, AP2, and AP3) as an example for specific explanation. The AP1 and the AP3 each include 1 transmitter, and the AP2 includes 2 transmitters (for convenience of distinction, referred to as TX1 and TX 2).

In response to receiving the trigger frame, each sender sends data to the station (denoted by STA in the figure). A channel frequency response between the AP1 and the station STA is denoted by H1, a channel frequency response between the sender TX1 of the AP2 and the station STA is denoted by H2, a channel frequency response between the sender TX2 of the AP2 and the station STA is denoted by H4, and a channel frequency response between the AP3 and the station STA is denoted by H3.

Specifically, the AP1 may transmit the data over a first set of subcarriers (denoted as @ DCM1 tones), and the data is a first STS (denoted as STS0) in STBC format. Assume STS 0: { S1, S2, S3, S4.

The sender TX1 of the AP2 may send the data over a first set of subcarriers (denoted as @ DCM1 tones), and the data is a second STS (denoted as STS1) in STBC format. Assume STS 1: -S2, S1, -S4, S3.

The sender TX2 of the AP2 may send the data over a second set of subcarriers (denoted as @ DCM2 tones), and the data is an STS1 in STBC format.

The AP3 may send the data over a second set of subcarriers (denoted as @ DCM2 tones), and the data is an STS0 in STBC format.

In a variation, the n sending ends may further include a fifth sending end, where the fifth sending end may send the data along with the sending configuration of the first sending end, the second sending end, the third sending end, or the fourth sending end, and data sending of the fifth sending end and data sending of the sending end along with the data sending of the fifth sending end have Cyclic Shift Diversity (CSD).

Further, the AP to which the fifth transmitting end belongs may be different from the AP to which the first transmitting end, the second transmitting end, the third transmitting end, or the fourth transmitting end belongs. Or the fifth transmitting end and any one or more of the first transmitting end, the second transmitting end, the third transmitting end and the fourth transmitting end belong to the same AP.

By analogy, the n sending ends may further include a sixth sending end, and the seventh sending ends are even more, and all of the sending ends may send data by using the sending method of the fifth sending end. The transmitting ends other than the first transmitting end, the second transmitting end, the third transmitting end and the fourth transmitting end may be transmitting ends which are allocated by a system to perform data transmission, or may be transmitting ends which are called by an AP to which the first transmitting end, the second transmitting end, the third transmitting end or the fourth transmitting end belongs to increase transmitting power.

For example, referring to fig. 5, fig. 5 is a schematic diagram of a third exemplary application scenario of the embodiment of the present invention. The application scenario is specifically illustrated by taking 4 APs (denoted as AP1, AP2, AP3, and AP4) as an example, where the AP1, the AP3, and the AP4 respectively include 1 sender, and the AP2 includes 2 senders (denoted as TX1 and TX2 for convenience of distinction). Therefore, in the application scenario, there are 5 transmitting ends, wherein the transmitting end TX2 of the AP2 can be regarded as the fifth transmitting end (which can also be regarded as a cyclic shift diversity transmitting end described below).

In response to receiving the trigger frame, each sender sends data to the station (denoted by STA in the figure). A channel frequency response between the AP1 and the station STA is denoted by H1, a channel frequency response between the sender TX1 of the AP2 and the station STA is denoted by H2, a channel frequency response between the sender TX2 of the AP2 and the station STA is denoted by H2', a channel frequency response between the AP3 and the station STA is denoted by H3, and a channel frequency response between the AP4 and the station STA is denoted by H4.

The sender TX2 of the AP2 may also send the data over a first set of subcarriers (denoted as @ DCM1 tones), and the data is an STS1 in STBC format. And, data transmission of the transmitter TX2 of the AP2 has cyclic shift diversity compared to data transmission of the transmitter TX1 of the AP 2.

The AP4 may send the data over a second set of subcarriers (denoted as @ DCM2 tones), and the data is an STS1 in STBC format.

For the station STA, in the present application scenario, the station STA may receive data streams { H1S1-H2 "S2, H1S2+ H2" S1, H1S3-H2 "S4, H1S4+ H2" S3., "through the channel frequency response of the first group of subcarriers @ DCM1 tones, where H2" refers to a synthesized frequency response received by AP2 at the station STA end through TX1 and TX2 transmission signals. The data streams H3S1-H4S2, H3S2+ H4S1, H3S3-H4S4, H3S4+ H4S3 may also be received via the channel frequency response of the second set of subcarriers @ DCM2 tones. The data can be obtained by joint demodulation of STBC and DCM for the two data streams.

In one implementation, the n transmitting ends may include a first transmitting end, a second transmitting end, and a third transmitting end.

And the third transmitting end respectively transmits the data through the first group of subcarriers and the second group of subcarriers, and the data is a second kind of STS in STBC format.

The scheme of this embodiment may be applied to a scenario with 3 APs, where each AP includes 1 transmitting end. Or, the scheme of this embodiment may be applicable to a scenario with 2 APs, where one AP includes 1 transmitting end, and another AP includes 2 transmitting ends.

In a variation, when the n transmitting ends may include a first transmitting end, a second transmitting end and a third transmitting end, in step S102, the first transmitting end transmits the data through the first group of subcarriers and the second group of subcarriers, respectively, and the data is a first STS in STBC format.

And the second transmitting end transmits the data through the first group of subcarriers, and the data is a second STS in an STBC format.

And the third transmitting end transmits the data through the second group of subcarriers, and the data is a second kind of STS in STBC format.

In a variation, the n transmitters may further include a cyclic shift diversity transmitter, where the cyclic shift diversity transmitter and any one or more of the first transmitter, the second transmitter, or the third transmitter belong to the same AP.

Specifically, the cyclic shift diversity transmitting end may transmit the data along with the transmission configuration of the first transmitting end, the second transmitting end, or the third transmitting end, and the data transmission of the cyclic shift diversity transmitting end has cyclic shift diversity compared with the data transmission of the transmitting end along with the data transmission of the cyclic shift diversity transmitting end.

Further, the number of the cyclic shift diversity transmitting ends may be one or more.

For example, the first transmitting end, the second transmitting end, and the third transmitting end may be transmitting ends to which the AP is allocated to perform the data transmission operation this time, and then any one or any plurality of APs may determine a transmitting end to which the AP is not allocated to perform the data transmission operation this time as the cyclic shift diversity transmitting end, so as to increase the transmission power.

Therefore, the sending mode combining the DCM sending mode and the STBC sending mode can realize quadruple diversity gain, and is beneficial to improving the reliability of the station as a receiver when receiving data. For example, in a fading channel, a transmission method combining the DCM transmission method and the STBC transmission method can better ensure reliable transmission of data.

In one implementation, the n transmitting ends may include a first transmitting end and a second transmitting end.

Accordingly, in step S102, the first transmitting end transmits the data through the first group of subcarriers and the second group of subcarriers, respectively, and the data is a first STS in STBC format.

And the second transmitting end respectively transmits the data through the first group of subcarriers and the second group of subcarriers, and the data is a second kind of STS in an STBC format.

The scheme of this embodiment may be applicable to a scenario with 2 APs, where each AP includes 1 transmitting end.

In a variation, when the n transmitting ends may include a first transmitting end and a second transmitting end, in step S102, the first transmitting end transmits the data through the first group of subcarriers; and the second sending end sends the data through the second group of subcarriers. That is, in this variation, the data transmitted by the first transmitting end and the second transmitting end is not STBC modulated.

In a variation, when the n transmitting ends may include a first transmitting end and a second transmitting end, in step S102, the first transmitting end transmits the data, and the data is a first STS in an STBC format; and the second sending end sends the data, and the data is a second STS in an STBC format. That is, in this variation, the data transmitted by the first transmitting end and the second transmitting end is not modulated by DCM.

In a variation, the n transmitting ends may further include a cyclic shift diversity transmitting end, where the cyclic shift diversity transmitting end and the first transmitting end and/or the second transmitting end belong to the same AP.

Specifically, the cyclic shift diversity transmitting end may transmit the data along with a transmission configuration of the first transmitting end or the second transmitting end, and the data transmission of the cyclic shift diversity transmitting end has cyclic shift diversity compared with the data transmission of the transmitting end along with the data transmission.

For example, the first transmitting end and the second transmitting end may be transmitting ends to which the APs are allocated to perform data transmission operation this time, and any one or any plurality of APs may determine a transmitting end to which the AP is not allocated to perform data transmission operation this time as the cyclic shift diversity transmitting end, so as to increase transmission power.

Thus, the DCM transmission method or the STBC transmission method alone can also achieve twice diversity gain. In practical applications, the adopted transmission mode can be flexibly adjusted according to the requirements of a multi-AP operating system to obtain diversity gain as high as possible.

In one implementation, the multiple APs may include a current access point and a cooperative access point, and the current access point may send the data to the cooperative access point using Out of Band (OOB).

For example, with continued reference to fig. 2, assuming that AP1 is the current access point and AP2, AP3, and AP4 are the cooperative access points, AP1 may send the data to AP2, AP3, and AP4 using OOB. Wherein the act of sending the data using OOB, which refers to a wireless connection or a wired connection of a different channel, may be performed prior to receiving the trigger frame. Wherein different channels refer to channels different from the channels for communication between the station and the AP.

In a specific embodiment, the OOB may be Ethernet (Ethernet), millimeter wave (mm wave), optical communication (light communication), or Wireless Local Area Network (WLAN) based on other channels or bandwidths (bands).

In one implementation, the current access point may include i transmitters, and the cooperative access point may include j transmitters, where i is greater than or equal to 1, j is greater than or equal to 1, and i + j is equal to n. Specifically, n transmitters composed of i transmitters and j transmitters may perform data transmission operations using the related description in the foregoing embodiments.

In one implementation, the number of the cooperative access points may be multiple, and each cooperative access point may include one or more transmitting ends. Specifically, the total number of the transmitting ends included in the plurality of cooperative access points is j.

Therefore, by adopting the scheme of the embodiment, a multi-AP joint transmission mechanism can be optimized, the diversity gain is better when data transmission is carried out in a multi-AP operating system, and the transmission reliability is improved.

Specifically, the transmission method combining the DCM transmission method and the STBC transmission method can achieve four times of diversity gain, which is advantageous for improving reliability when a station as a receiver receives data.

For example, in a fading channel, a transmission method combining the DCM transmission method and the STBC transmission method can better ensure reliable transmission of data. Further, the DCM transmission method or the STBC transmission method alone can also achieve twice diversity gain.

The multi-AP operating system of the OFDM system according to the embodiment can flexibly select a transmission mode and a specific transmission configuration according to the number of APs and the number of transmission ends of each AP, so as to give consideration to diversity gain and operation flexibility. The number of the transmitting terminals of each AP may refer to the number of the transmitting terminals allocated to perform the data transmission operation by each AP this time.

Fig. 6 is a schematic structural diagram of an access point according to an embodiment of the present invention. The access point includes at least one transmitting end. Further, the number of the at least one transmitting end is less than n.

Referring to fig. 6, the access point 6 in this embodiment may include: a determining module 61, configured to determine, for each sending end, a sending mode in response to receiving a trigger frame, where sending configurations of different sending ends are different; a sending module 62, where the at least one sending end sends the data by using corresponding sending configurations; wherein, the sending mode adopted by the at least one sending end is selected from: the method comprises a DCM transmission mode, an STBC transmission mode and a transmission mode combining the DCM transmission mode and the STBC transmission mode, wherein each transmission mode comprises a plurality of transmission configurations.

Specifically, the access point 6 includes, but is not limited to, any communicable terminal device such as a mobile phone, a computer, a tablet computer, a router, and the like.

For more contents of the operation principle and the operation mode of the access point 6, reference may be made to the relevant descriptions in fig. 1 to fig. 5, which are not described herein again.

Fig. 7 is a flowchart of a data receiving method for multi-AP operation in an OFDM system according to an embodiment of the present invention.

The scheme of this embodiment may be executed by a station, where the station is configured to receive data sent by each AP by using the scheme in the embodiments shown in fig. 1 to fig. 5. The multiple APs may include n transmitting ends, where n is greater than or equal to 2.

Specifically, referring to fig. 7, the data receiving method for multi-AP operation of the OFDM system according to this embodiment may include the following steps:

step S701, determining whether to adopt a multi-AP receiving mode to receive the data;

step S702, when determining to adopt the multi-AP receiving mode to receive the data, receiving the data which are simultaneously transmitted by the n transmitting terminals by adopting the corresponding transmitting configuration, wherein the transmitting configurations of different transmitting terminals are different;

wherein, the transmission modes adopted by the n transmitting ends are selected from: the method comprises a DCM transmission mode, an STBC transmission mode and a transmission mode combining the DCM transmission mode and the STBC transmission mode, wherein each transmission mode comprises a plurality of transmission configurations.

Those skilled in the art will understand that the steps S701 to S702 can be regarded as execution steps corresponding to the steps S101 to S102 described in the above embodiments shown in fig. 1 to 5, and the two steps are complementary in terms of specific implementation principle and logic. Therefore, the explanation of the terms in the present embodiment may refer to the description of the embodiments shown in fig. 1 to fig. 5, and will not be repeated here.

In one implementation, the step S701 may include: and after receiving a trigger notification sent by the current access point, sending a trigger frame to the n sending ends. At this time, the station may determine to receive, in a multi-AP reception manner, data sent by each sender in response to the trigger frame.

In a variation, the step S701 may include: and receiving a trigger frame sent by the current access point to the cooperative access point, and determining to receive the data by adopting a multi-AP receiving mode. Wherein, receiving may refer to monitoring a trigger frame sent by the current access point to the cooperative access point.

Specifically, referring to fig. 8, the station 8 in this embodiment may include: a determining module 81, configured to determine whether to receive the data in a multi-AP receiving manner; a receiving module 82, configured to receive the data sent by the sending end with the corresponding sending configuration when determining to receive the data in a multi-AP receiving manner, where sending configurations of different sending ends are different; wherein, the transmission modes adopted by the n transmitting ends are selected from: the method comprises a DCM transmission mode, an STBC transmission mode and a transmission mode combining the DCM transmission mode and the STBC transmission mode, wherein each transmission mode comprises a plurality of transmission configurations.

Specifically, the site 8 may include, but is not limited to, any communicable terminal device such as a mobile phone, a computer, a tablet computer, a router, and the like.

For more details on the working principle and working mode of the station 8, reference may be made to the relevant description in fig. 7, which is not described herein again.

Further, the embodiment of the present invention further discloses a storage medium, on which computer instructions are stored, and when the computer instructions are executed, the method technical solution described in the embodiments shown in fig. 1 to fig. 5 or the embodiment shown in fig. 7 is executed. Preferably, the storage medium may include a computer-readable storage medium such as a non-volatile (non-volatile) memory or a non-transitory (non-transient) memory. The storage medium may include ROM, RAM, magnetic or optical disks, etc.

Although the present invention is disclosed above, the present invention is not limited thereto. Various changes and modifications may be effected therein by one skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. A data transmission method for multi-AP operation of an OFDM system is disclosed, wherein the multi-AP comprises n transmitting terminals, n is more than or equal to 2, and the data transmission method comprises the following steps:

for each sending end, responding to the received trigger frame, determining a sending mode, wherein the sending configurations of different sending ends are different;

the n sending ends respectively adopt corresponding sending configurations to send the data;

2. The data transmission method according to claim 1, wherein the n transmitting ends are associated with a channel, the channel comprises a plurality of subcarriers, and the plurality of subcarriers comprise a first group of subcarriers and a second group of subcarriers which are disjoint; the DCM transmission scheme is a scheme for transmitting the same data through the first group of subcarriers and/or the second group of subcarriers, respectively.

3. The data transmission method according to claim 2, wherein the subcarriers in the first set of subcarriers and the subcarriers in the second set of subcarriers form pairs of subcarriers, and data transmitted by each pair of subcarriers is the same.

4. The data transmission method according to claim 2, wherein the n sending ends include a first sending end, a second sending end, a third sending end, and a fourth sending end, and the n sending ends respectively send the data using corresponding sending configurations includes:

the first sending end sends the data through the first group of subcarriers, and the data is a first STS in an STBC format;

the second transmitting end transmits the data through the second group of subcarriers, and the data is a first kind of STS in STBC format;

the third transmitting end transmits the data through the first group of subcarriers, and the data is a second kind of STS in STBC format;

5. The data transmission method according to claim 2, wherein the n transmitting ends include a first transmitting end, a second transmitting end, and a third transmitting end, and the n transmitting ends respectively transmit the data using the corresponding transmission configurations include:

the third transmitting end respectively transmits the data through the first group of subcarriers and the second group of subcarriers, and the data is a second kind of STS in STBC format.

6. The data transmission method according to claim 2, wherein the n transmitting ends include a first transmitting end, a second transmitting end, and a third transmitting end, and the n transmitting ends respectively transmit the data using the corresponding transmission configurations include:

the first transmitting end transmits the data through the first group of subcarriers and the second group of subcarriers respectively, and the data is a first kind of STS in an STBC format;

the second transmitting end transmits the data through the first group of subcarriers, and the data is a second kind of STS in STBC format;

7. The data transmission method according to claim 2, wherein the n transmitting ends include a first transmitting end and a second transmitting end, and the n transmitting ends respectively transmit the data using the corresponding transmission configurations includes:

8. The data transmission method according to claim 2, wherein the n transmitting ends include a first transmitting end and a second transmitting end, and the n transmitting ends respectively transmit the data using the corresponding transmission configurations includes:

the first sending end sends the data through the first group of subcarriers;

and the second sending end sends the data through the second group of subcarriers.

9. The data transmission method according to claim 1, wherein the n transmitting ends include a first transmitting end and a second transmitting end, and the n transmitting ends respectively transmit the data using the corresponding transmission configurations includes:

the first sending end sends the data, and the data is a first STS in an STBC format;

and the second sending end sends the data, and the data is a second STS in an STBC format.

10. The data transmission method according to any one of claims 1 to 9, wherein the n transmitting ends further include a cyclic shift diversity transmitting end, and the n transmitting ends respectively transmit the data using corresponding transmission configurations further include:

the cyclic shift diversity transmitting end continues to transmit the data using the transmission configuration of any one of the n transmitting ends except for the cyclic shift diversity transmitting end, and the data transmission of the cyclic shift diversity transmitting end has cyclic shift diversity compared with the data transmission of the transmitting end continued to the cyclic shift diversity transmitting end.

11. The data transmission method according to claim 1, wherein the multiple APs comprise a current access point and a cooperative access point, and the current access point transmits the data to the cooperative access point using OOB.

12. The data transmission method according to claim 11, wherein the current access point includes i transmitters, and the cooperative access point includes j transmitters, where i is greater than or equal to 1, j is greater than or equal to 1, and i + j is equal to n.

13. The data transmission method according to claim 11, wherein the number of the cooperative access points is multiple, and each cooperative access point comprises one or more transmitting ends.

14. An access point, comprising at least one transmitting end, further comprising:

the determining module is used for responding to the received trigger frame and determining a sending mode for each sending end, wherein the sending configurations of different sending ends are different;

the sending module is used for sending the data by the at least one sending end by adopting corresponding sending configuration;

wherein, the sending mode adopted by the at least one sending end is selected from: the method comprises a DCM transmission mode, an STBC transmission mode and a transmission mode combining the DCM transmission mode and the STBC transmission mode, wherein each transmission mode comprises a plurality of transmission configurations.

15. A data receiving method for multi-AP operation of an OFDM system is provided, wherein the multi-AP comprises n sending ends, and n is more than or equal to 2, and the data receiving method comprises the following steps:

determining whether to receive the data in a multi-AP receiving mode;

when the data are determined to be received in a multi-AP receiving mode, the data which are simultaneously transmitted by the n transmitting terminals by adopting the corresponding transmitting configurations are received, wherein the transmitting configurations of different transmitting terminals are different;

16. A station, comprising:

a determining module, configured to determine whether to receive the data in a multi-AP receiving manner;

the receiving module is used for receiving the data which are simultaneously transmitted by the n transmitting ends by adopting corresponding transmitting configurations when the data are determined to be received by adopting a multi-AP receiving mode, wherein the transmitting configurations of different transmitting ends are different;

17. A storage medium having stored thereon computer instructions operable to perform the method of any one of claims 1 to 13 or the steps of the method of claim 15.