WO2015188698A1 - Procédé et dispositif de transmission de données en liaison montante - Google Patents

Procédé et dispositif de transmission de données en liaison montante Download PDF

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Publication number
WO2015188698A1
WO2015188698A1 PCT/CN2015/079994 CN2015079994W WO2015188698A1 WO 2015188698 A1 WO2015188698 A1 WO 2015188698A1 CN 2015079994 W CN2015079994 W CN 2015079994W WO 2015188698 A1 WO2015188698 A1 WO 2015188698A1
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WIPO (PCT)
Prior art keywords
message
station
access point
wireless access
channel
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PCT/CN2015/079994
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English (en)
Chinese (zh)
Inventor
树贵明
权荣训
容志刚
陆苏
丁志明
杜振国
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华为技术有限公司
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Publication of WO2015188698A1 publication Critical patent/WO2015188698A1/fr

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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W72/00—Local resource management
    • H04W72/50—Allocation or scheduling criteria for wireless resources
    • H04W72/54—Allocation or scheduling criteria for wireless resources based on quality criteria
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W74/00—Wireless channel access
    • H04W74/04—Scheduled access

Definitions

  • the embodiments of the present invention relate to the field of wireless communications technologies, and in particular, to an uplink data transmission method and apparatus.
  • a wireless AP Access Point
  • the function of a wireless AP is to convert a wired network into a wireless network, which is a communication bridge between a wired network and a wireless network.
  • a wireless AP and a plurality of STAs stations it serves share a communication channel through a carrier sense multiple access mechanism, and use a random backoff mechanism to reduce the conflict therebetween.
  • the wireless AP indicates, by using an uplink synchronization indication frame, an STA that is allowed to send uplink data, and after receiving a short frame interval of the uplink synchronization indication frame, the STA follows the uplink synchronization indication according to itself.
  • the location indicated in the frame selects a corresponding subchannel, and an RTS (Request To Send) message is sent to indicate the uplink channel resource information that it needs.
  • RTS Request To Send
  • the wireless AP After receiving the RST message sent by the STA, the wireless AP sends a CTS (Clear To Send) message to the STA through the corresponding subchannel, and indicates the uplink channel resource allocated to the STA in the CTS message, and the STA is in the After a short frame interval, uplink data is transmitted on the specified channel resource.
  • the wireless AP can simultaneously allocate different channel resources to multiple STAs supporting OFDMA (Orthogonal Frequency Division Multiple Access).
  • OFDMA Orthogonal Frequency Division Multiple Access
  • the subchannel is used to transmit data in the segment, and STA2 uses the subchannel to transmit data in the period from t2 to t3.
  • a subchannel can only be used by one STA at a certain time, that is, the same time-frequency channel
  • the source can only be used by one STA, so spectrum usage is less efficient.
  • an uplink data transmission method and apparatus are provided, so that multiple STAs served by a wireless AP use the same time-frequency channel resource to send uplink data in parallel, thereby improving spectrum usage efficiency.
  • an embodiment of the present invention provides an uplink data transmission method, including:
  • the first station Receiving, by the first station, an uplink transmission indication message sent by the wireless access point, where the uplink transmission indication message includes information for indicating that the first station and the at least one other station are allowed to send uplink data;
  • the channel resources allocated by the first station and the second station that are not related to the channel are the same;
  • the first station sends uplink data by using channel resources allocated by the wireless access point.
  • the first station sends the first message to the wireless access point according to the uplink transmission indication message, including:
  • the first station sends the first message to the wireless access point according to the uplink transmission indication message.
  • a message; the third message includes at least channel estimation information of the second station.
  • the first message sent by the first station includes N training domains, where N is greater than or equal to The number of stations in the uplink transmission indication message that are allowed to send uplink data, where the N a training field in the training domain is used to store channel estimation information of the first station;
  • the first station transmits a first message including channel estimation information of the first station, where the first station transmits the channel estimation information in the first message by using the entire channel resource.
  • the first message further includes a data field for storing uplink transmission information
  • the sending, by the first station, the first message to the wireless access point according to the uplink transmission indication message further includes:
  • the first station transmits the data field in the first message by using the determined subchannel.
  • the first station sends the channel estimate in the first message by using the entire channel resource Information, including:
  • the first station transmits channel estimation information of the first station in parallel on each of the entire channel resources.
  • the uplink transmission indication message further includes information used to indicate an order in which the first station sends the first message
  • the first station is to the radio access according to the sequence indicated by the uplink transmission indication message Point sending the first message, including:
  • the first station transmits the first message to the wireless access point at a time indicated by the time information using an entire channel resource.
  • the first station determines, according to the uplink transmission indication message, that the first site is The order in the first site and the at least one other site includes:
  • the first station uses the wireless connection
  • the channel resources allocated by the inbound point send uplink data including:
  • the first station sends uplink data by using the channel resource allocated by the wireless access point.
  • the receiving, by the first station, the wireless access point is sent Before the uplink transmission indication message the method further includes:
  • a query response message to the wireless access point where the query response is The information includes at least information indicating that the first station has uplink data transmission, so that the wireless access point generates the uplink transmission indication message according to the query response message.
  • the embodiment of the present invention further provides a channel resource allocation method, including:
  • the wireless access point sends an uplink transmission indication message, where the uplink transmission indication message includes information indicating that the N stations are allowed to send uplink data, where N ⁇ 2, and N is an integer;
  • the wireless access point allocates the same channel resource to at least two stations in the N stations that are not related to each other, so that at least two stations that are not related to each other use the same channel resource to simultaneously send uplink data. .
  • the method before the sending, by the wireless access point, the uplink transmission indication message, the method further includes:
  • the wireless access point sends an uplink query message, where the uplink query message is used to query which stations have uplink data to be sent;
  • the wireless access point receives N query response messages respectively returned by the N stations, and each of the query response messages includes at least information indicating that the site corresponding to the query response message has uplink data transmission, so that the The wireless access point generates the uplink transmission indication message according to the N query response messages respectively returned by the N stations.
  • the method further includes:
  • the wireless access point allocates different channel resources for at least two stations related to the channels in the N stations.
  • the present invention further provides an uplink data transmission apparatus, which is applied to a first site, where the apparatus includes:
  • a receiving unit configured to receive an uplink transmission indication message sent by the wireless access point, where the uplink transmission indication message includes information used to indicate that the first station and the at least one other station are allowed to send uplink data;
  • a sending unit configured to send, according to the uplink transmission indication message, a first message to the wireless access point, where the first message includes at least channel estimation information of the first station, so that the wireless access point is configured according to Determining, by the channel estimation information of the first station, channel estimation information of the second station, whether the channel of the first station and the channel of the second station are related, where the second station is in the at least one other station One site;
  • the receiving unit is further configured to receive a second message sent by the wireless access point, where the second message includes information about a channel resource allocated by the wireless access point to the first station;
  • the channel resources allocated by the first station and the second station whose ingress points are not related to the channel are the same;
  • the sending unit is further configured to send uplink data by using a channel resource allocated by the wireless access point.
  • the sending unit is configured to: when the first message is sent to the wireless access point according to the uplink transmission indication message, specifically Sending, by the second station, the first message to the wireless access point according to the uplink transmission indication message, and sending the first message to the wireless access point according to the uplink transmission indication message;
  • the third message includes at least channel estimation information of the second station.
  • the first message includes N training fields, where N is greater than or equal to that allowed in the uplink transmission indication message.
  • N is greater than or equal to that allowed in the uplink transmission indication message.
  • the number of stations that send uplink data, and one training field in the N training domains is used to store channel estimation information of the first station;
  • the sending unit is configured to: when the first message is sent to the wireless access point according to the uplink transmission indication message, specifically:
  • Transmitting a first message including channel estimation information of the first station wherein the transmitting unit transmits the channel estimation information in the first message by using an entire channel resource.
  • the first message further includes a data field for storing the uplink transmission information
  • the sending unit When the sending unit sends the first message to the wireless access point according to the uplink transmission indication message, the sending unit is further configured to:
  • the sending unit sends the channel estimation information in the first message by using the entire channel resource
  • the channel estimation information of the first station is specifically sent in parallel on each of the entire channel resources.
  • the sending unit is configured to determine, according to the uplink transmission indication message, that the first site is in the first When the order in a site and the at least one other site is specifically used to:
  • the method is specifically configured to: when the second station uses the channel resource allocated by the wireless access point to send uplink data, use the wireless access point The allocated channel resources send uplink data.
  • the receiving unit is further configured to receive an uplink query message sent by the wireless access point, where the uplink query message includes information used to query whether the first station has uplink data transmission;
  • the sending unit is further configured to: return an inquiry response message to the wireless access point, where the query response message includes at least information indicating that the first station has uplink data transmission, so that the The wireless access point generates the uplink transmission indication message according to the query response message.
  • the present invention further provides an uplink channel resource allocation apparatus, which is applied to a wireless access point, and includes:
  • a sending unit configured to send an uplink transmission indication message, where the uplink transmission indication message includes information for indicating that N stations are allowed to send uplink data, where N ⁇ 2, and N is an integer;
  • a receiving unit configured to receive N channel estimation information that are sent by the N stations according to the uplink transmission indication message
  • a channel estimation unit configured to determine, according to the N channel estimation information received by the receiving unit, a correlation of channels of the N stations;
  • a channel resource allocation unit configured to allocate the same channel resource to at least two stations in which the channels are uncorrelated among the N stations, so that at least two stations that are not related to the channel use the same channel resource to simultaneously send uplink data.
  • the sending unit is further configured to send an uplink query message, where the uplink query message is used to query which stations have uplink data to be sent;
  • the receiving unit is further configured to receive N query response messages respectively returned by the N stations, where each of the query response messages includes at least information indicating that the site corresponding to the query response message has uplink data, so that The wireless access point generates the uplink transmission indication message according to the N query response messages respectively returned by the N stations.
  • the channel resource allocation unit is further configured to allocate different channel resources for at least two stations related to channels in the N stations.
  • the present invention further provides a terminal device, where the terminal device is a first site, and the terminal device includes any one of the uplink data transmission devices provided by the third aspect.
  • the present invention provides a wireless access apparatus, including the uplink channel resource allocation apparatus according to any one of the fourth aspects.
  • the wireless AP determines the correlation of the channels of the multiple STAs according to the respective channel estimation information reported by the multiple STAs, and then the wireless AP may be The at least two STAs that are not related to each other are allocated the same channel resource, so that multiple STAs that are allocated the same channel resource use the same channel resource to send uplink data in parallel, that is, multiple STAs use the same time-frequency channel resource to send uplink data, thereby The utilization efficiency of channel resources in uplink transmission is improved.
  • FIG. 1 is a schematic flowchart diagram of a channel resource allocation method according to an embodiment of the present invention
  • FIG. 2 is a schematic flowchart of an uplink data transmission method according to an embodiment of the present invention.
  • FIG. 3 is a schematic flowchart of another uplink data transmission method according to an embodiment of the present invention.
  • 4(a) is a schematic diagram showing the format of a MAC layer of an ULTA message according to an embodiment of the present invention
  • 4(b) is a schematic diagram showing the format of another ULTA message MAC layer according to an embodiment of the present invention.
  • FIG. 5 is a schematic diagram of a format of a MAC layer of a first CTS message according to an embodiment of the present invention
  • FIG. 6 is a schematic diagram of an AID MAP domain according to an embodiment of the present invention.
  • FIG. 7 is a schematic diagram of a first CTS message of multiple STAs according to an embodiment of the present invention.
  • FIG. 8 is a schematic diagram of a message format of a second CTS message MAC layer according to an embodiment of the present invention.
  • FIG. 9 is a schematic diagram of an uplink data transmission method corresponding to the embodiment of FIG. 3;
  • FIG. 10 is a schematic flowchart diagram of another uplink data transmission method according to an embodiment of the present invention.
  • FIG. 11 is a schematic diagram of a message format of a ULA message according to an embodiment of the present invention.
  • FIG. 12 is a schematic diagram of a message format of another ULA message according to an embodiment of the present invention.
  • FIG. 13 is a schematic diagram of an uplink data transmission method corresponding to the embodiment of FIG. 10; FIG.
  • FIG. 14 is a schematic flowchart diagram of another uplink data transmission method according to an embodiment of the present invention.
  • FIG. 15 is a schematic diagram of an uplink data transmission method corresponding to the embodiment of FIG. 14;
  • FIG. 16 is a schematic flowchart diagram of another uplink data transmission method according to an embodiment of the present invention.
  • FIG. 17 is a schematic diagram of an uplink data transmission method corresponding to the embodiment of FIG. 16;
  • FIG. 18 is a schematic diagram of an uplink data transmission apparatus according to an embodiment of the present invention.
  • FIG. 19 is a schematic diagram of another uplink data transmission apparatus according to an embodiment of the present invention.
  • FIG. 20 is a schematic diagram of a channel resource allocation apparatus according to an embodiment of the present invention.
  • FIG. 21 is a schematic diagram of another channel resource allocation apparatus according to an embodiment of the present invention.
  • FIG. 1 is a schematic flowchart of a method for allocating a channel resource according to an embodiment of the present invention.
  • the method is applied to a wireless AP, where the STA may be a mobile phone, a personal computer, or a tablet computer, as shown in FIG.
  • the method can include the following steps:
  • the wireless AP sends an ULTA (Up Link Transmission Announce) message, where the ULTA message includes information indicating that the N STAs are allowed to send uplink data.
  • N is an integer and N ⁇ 2.
  • the ULTA message may be an independent message and sent by the wireless AP independently; or the information indicating that the N STAs are allowed to send uplink data may be encapsulated into one information element, and included in other messages (eg, beacon Beacon message) Sent in.
  • the uplink transmission indication message described in the embodiments of the present invention is only used to refer to a message sent by the wireless AP, and is not used to limit the message. In a specific implementation manner, the uplink transmission indication message is used. Other names may be used as long as they include information for instructing N STAs to transmit uplink data.
  • the wireless AP receives N channel estimation information that are sent by the N STAs according to the ULTA.
  • the N STAs may determine, according to the ULTA message, whether the wireless AP sends uplink data to the STA; and the ULTA message indicates that the N STAs are allowed to send uplink data,
  • the N STAs return respective channel estimation information to the wireless AP, that is, each of the N STAs sends the channel to the wireless AP.
  • the STA may carry the channel estimation information in a certain message, for example, in a clear to send (CTS) message, or carried in a request to send (request to send, RTS) message.
  • CTS clear to send
  • RTS request to send
  • the wireless AP when it sends the ULTA message, it may not know which STAs need to send uplink data. When the wireless AP does not know which STAs need to send uplink data, the wireless AP may indicate that some STAs are allowed in the ULTA message. The uplink data is sent. However, the STAs that are allowed to send uplink data do not necessarily have uplink data to be sent. When an STA that is allowed to send uplink data has uplink data to send, the channel estimation information of the STA may be returned to the wireless AP. When one STA that is allowed to transmit uplink data has no uplink data to transmit, the channel estimation information is not returned to the wireless AP.
  • the N in this embodiment may indicate the number of STAs that need to send the uplink data.
  • the ULTA message may further include other information, for example, may further include information for indicating that other STAs other than the N STAs send uplink data.
  • the ULTA message indicates that STA1 to STA5 are allowed to send uplink data, but only STA1 to STA3 need to send uplink data.
  • N can be 3, and N STAs represent STA1 to STA3.
  • the wireless AP determines, according to the received N channel estimation information, a correlation of channels of the N STAs.
  • the wireless AP can determine whether the channels of each of the N STAs are related according to the N channel estimation information received from the N STAs.
  • the channel of the STA in each embodiment of the present invention may be a channel for transmitting data between the STA and the wireless AP.
  • the wireless AP allocates the same channel resource to at least two STAs that are not related to each other in the N stations, so that at least two STAs whose channels are not related to each other simultaneously transmit uplink data by using the same channel resource.
  • the wireless AP may allocate the same channel resource for STA1, STA2, and STA3; or, the wireless AP may allocate the same channel resource for STA1 and STA2, and allocate other channel resources for STA3. Or, the wireless AP may allocate the same channel resource for STA1 and STA3, and allocate other channel resources for STA2; or, the wireless AP may allocate the same channel resource for STA2 and STA3, and allocate other channel resources for STA1.
  • At least two STAs that are assigned the same channel resource can simultaneously transmit data to the wireless AP using the same channel resource. That is, multiple STAs that are allocated the same channel resource can transmit uplink data in parallel using the same time-frequency channel resource.
  • the channels of the multiple STAs are not related to each other, that is, the channels of any two of the multiple STAs are not related.
  • the wireless AP needs to allocate different channel resources for at least two STAs associated with the channel.
  • the wireless AP may carry the information of the allocated channel resource in a certain message (for example, a CTS message or an RTS message) and send the information to the corresponding STA.
  • a certain message for example, a CTS message or an RTS message
  • the wireless AP After receiving the channel estimation message sent by the N STAs, the wireless AP confirms that the N STAs have uplink data to be transmitted. Then, after allocating channel resources for the N STAs, the wireless AP sends a message carrying the channel resource information, such as the second CTS message, to the N STAs.
  • the process in which the wireless AP allocates channel resources to multiple STAs may be that the wireless AP first determines which channels of the STAs are irrelevant according to the message that is sent by each STA and includes the respective channel estimation information.
  • the STAs whose channels are not related may be grouped into one group, and it is determined that the group of STAs can share the same channel resource.
  • the wireless AP allocates different channel resources to them to avoid collisions when transmitting uplink data.
  • the size of the channel resource allocated by the AP to the STA may be determined according to the uplink transmission information of the STA and the data transmission capability supported by the wireless AP itself, but is not included in the message (the first CTS message or the RTS message) sent by the STA.
  • the wireless AP may allocate a suitable uplink channel resource to each STA according to its own data transmission capability and the latest uplink bandwidth requirement of each STA, or the wireless AP may directly be based on its own data transmission capability.
  • Each STA allocates a predetermined uplink channel resource.
  • the wireless AP may send N second CTS messages to the N STAs, where each second CTS message includes a channel resource allocated by the wireless AP for the STA corresponding to the second CTS message.
  • Information may be included in the N STAs.
  • the wireless AP may transmit only one second CTS message, and the second CTS message includes information of channel resources allocated for the N STAs.
  • the wireless AP may further receive uplink data that is transmitted by the STA through the channel resource allocated by the wireless AP, that is, perform S150.
  • the wireless AP receives uplink data that is sent by the STA by using the channel resource allocated by the wireless AP for the STA1.
  • the multiple STAs that are allocated the same channel resource can simultaneously send uplink data by using the allocated channel resources. For example, if the channel of STA1 is not related to the channel of STA2, and the wireless AP allocates the same channel resource for STA1 and STA2, STA1 and STA2 can simultaneously transmit uplink data to the wireless AP by using the same channel resource.
  • the wireless AP may determine the correlation of the channels of the multiple STAs according to the channel estimation information of the STA, and may allocate the same channel resources to the at least two STAs whose channels are not related to each other, so that the multiple channels are uncorrelated.
  • the station can transmit uplink data on the same channel resource, that is, stations with multiple channels uncorrelated can use the same time-frequency channel resource to transmit uplink data in parallel, which improves the utilization of channel resources (ie, spectrum) in uplink transmission. effectiveness.
  • FIG. 2 is a schematic flowchart of an uplink data transmission method according to an embodiment of the present invention.
  • the method describes an uplink data transmission process from the STA1 side.
  • the method uses a wireless AP, STA1, and STA2 as an example for description. As shown in FIG. 2, the method includes:
  • STA1 receives an ULTA message sent by a wireless AP, where the ULTA message includes information for indicating that STA1 and at least one other STA are allowed to send uplink data.
  • the STA2 may be one of the at least one other STA. Both STA1 and STA2 have uplink data to be sent.
  • STA1 sends a first message to the wireless AP according to the ULTA message, where the first message includes at least channel estimation information of STA1, so that the wireless AP can determine STA1 according to channel estimation information of STA1 and channel estimation information of STA2. Whether the channel is related to the channel of STA2.
  • the channel estimation information of the STA2 may be sent by the STA2 to the wireless AP according to the ULTA message.
  • STA1 After receiving the ULTA message sent by the wireless AP, STA1 first determines whether the wireless AP allows STA1 to send uplink data. If the wireless AP allows STA1 to send uplink data, and STA1 needs to send uplink data, the first message is sent to the wireless AP (for example, The first CTS message includes at least the channel estimation information of the STA1, and may further include the uplink transmission information of the STA1. Similarly, the STA2 may send a third message to the wireless AP according to the ULTA message, where the third message includes at least the channel estimation information of the STA2, and may further include the uplink transmission information of the STA2.
  • the first message or the third message may be a CTS message sent by the STA to the wireless AP, or may be an RTS message sent by the STA to the wireless AP.
  • the uplink transmission information may be set to preset information in the first message, for example, a binary number "0" or "1", or STA1 does not send the first message.
  • the first message sent by STA1 and the third message sent by STA2 may be sent in parallel. In another embodiment of the present invention, the first message sent by STA1 and the third message sent by STA2 may be sequentially transmitted in a time division manner.
  • the STA1 receives the second message sent by the wireless AP, where the second message includes information about a channel resource allocated by the wireless AP for the STA1, and the wireless AP allocates the same channel resource for the channel unrelated STA1 and STA2.
  • the wireless AP After receiving the first message sent by STA1, the wireless AP confirms that STA1 has uplink data transmission. Then, the wireless AP determines whether the channel of STA1 and the channel of STA2 are related according to the channel estimation information of STA1 and the channel estimation information of STA2. If not, Then, STA1 and STA2 can be allocated the same channel resource, and the second channel is used to inform STA1 and STA2 that the wireless AP allocates channel resources for STA1 and STA2.
  • STA1 uses the wireless AP to send uplink data to the channel resource allocated by STA1.
  • STA1 and STA2 simultaneously transmit uplink data by using the same channel resource allocated by the wireless AP.
  • the uplink data transmission method provided by this embodiment, where STA1 receives the wireless AP transmission After the ULTA message, the first message including the channel estimation information of STA1 is returned to the wireless AP, so that the wireless AP determines, according to the channel estimation information of STA1 and the channel estimation information of STA2, that the channel of STA1 is not correlated with the channel of STA2, and is STA1.
  • STA1 and STA2 use the same channel resource to transmit uplink data, that is, STA1 and STA2 with uncorrelated channels can utilize the same time-frequency channel resource, thereby improving the utilization efficiency of channel resources in uplink transmission.
  • FIG. 3 a schematic flowchart of a method for an exemplary embodiment of an uplink data transmission method according to the present invention is shown.
  • This embodiment uses a wireless AP, STA1, STA2, and STA3 as an example for description.
  • the method may include the following steps:
  • the wireless AP sends an ULTA message, where the ULTA message includes information indicating that STA1, STA2, and STA3 are allowed to send uplink data.
  • the wireless AP may send the ULTA message by broadcast or multicast. Then, S320 is performed.
  • FIG. 4(a) shows a message format diagram of an ULTA message.
  • the ULTA message in this embodiment is an independent message, and the ULTA message can be separately sent by the wireless AP.
  • the format of the MAC layer of the ULTA message is from left to right: Frame Control, Duration field, RA (receiver address) field, AID MAP (association) Identification distribution) domain and FCS (Frame Check Sequence) domain.
  • the association identifier is (Association Identifier, AID).
  • the AID MAP field is used to store information indicating that the STA is allowed to transmit uplink data, and information that the STA sends the first CTS message.
  • the rank of each bit in the AID MAP field corresponds to the STA of the corresponding AID value
  • the AID MAP field may contain the 2008 bit binary.
  • the first bit of the AID MAP corresponds to the site with the AID being 1
  • the second bit corresponds to the site with the AID of 2, and so on
  • the 2008 bit corresponds to the STA with the AID of 2008.
  • a certain bit of the AID MAP field is set as the preset flag, it indicates that the corresponding STA is allowed to send uplink data. Otherwise, the corresponding station is not allowed to send uplink data.
  • the preset mark may be pre-defined, for example, the preset mark may be specified as “1” or “0”; when the preset mark is “1”, if the third bit of the AID MAP field is “1”, the permission is allowed.
  • the uplink data is sent by a site with an AID of 3 (decimal).
  • the ULTA message can also be an information element, including Sent in other messages (eg beacon message Beacon).
  • Figure 4 (b) shows the message format when the ULTA message is an information element.
  • the format of the MAC layer of the information element is from left to right: Element ID, Length, AID MAP (Association ID Distribution) )area.
  • the content and meaning of the AID MAP domain are the same as those of the AID MAP domain in Figure 4 (a), and are not described here.
  • STA1 sends a first CTS message to the wireless AP according to the ULTA message;
  • STA2 sends a first CTS message to the wireless AP according to the ULTA message;
  • STA3 sends a first CTS message to the wireless AP according to the ULTA message.
  • the first CTS message sent by the STA1 includes at least the channel estimation information of the STA1
  • the first CTS message sent by the STA2 includes at least the channel estimation information of the STA2
  • the first CTS message sent by the STA3 includes at least the channel estimation information of the STA3. Then S330 is executed.
  • STA1 after receiving the ULTA message sent by the wireless AP, STA1 first determines whether the AID corresponding data bit of STA1 in the AID MAP domain is a preset flag, and if it is a preset flag, determining that the wireless AP allows STA1 to send uplink data, and then Execute S320. Similarly, STA2 and STA3 may also perform S320 after determining that the wireless AP allows STA2 and STA3 to transmit uplink data.
  • the three CTS messages sent by STA1, STA2, and STA3 may be simultaneously sent, and the CTS message sent by the STA is used as the first CTS message as an example for description.
  • the first CTS message sent by the STA1 may be the first message in the embodiment shown in FIG. 2, and the first CTS message sent by the STA2 or the STA3 may be equivalent to the third message in the embodiment shown in FIG.
  • FIG. 5 is a schematic diagram of a MAC layer message format of a first CTS message according to an embodiment of the present invention.
  • the first CTS message is from left to right: Frame Control, Duration, and AID. (Association Identifier) field, Bandwith information field, and FCS (Frame Check Sequence) field.
  • the Bandwith information field is used to store uplink transmission information of the STA.
  • the MAC layer message of the CTS message specified in the existing WLAN standard IEEE 802.11 protocol is used.
  • the 64-bit receive address (RA) field is redefined as the AID field (for example, 16 bits) and the Bandwith information field (for example, 24 bits).
  • the AID field is used to store the STA's associated identifier AID.
  • the channel bandwidth resource information field is used to store bandwidth resource information requested by the STA.
  • the first CTS message may include a header field and a data domain in a physical layer format, where the MAC layer of the first CTS message is encapsulated into a data domain of the first CTS message;
  • the number of TF fields set is not less than the number of STAs that the wireless AP is allowed to send uplink data.
  • the number of TF domains is indicated by an ULTA message, that is, the number of STAs that are allowed to send uplink data may be indicated in the ULTA message, which is the number of TF domains.
  • One TF field in a plurality of TF domains is used to store channel estimation information, which is used to enable the AP to estimate the uplink transmission channel characteristics of the STA.
  • the TF field may be an LTF (long train filed) field or an STF (short train filed) field.
  • the process of the STA1 transmitting the corresponding first CTS message to the wireless AP may include the following steps 11)-16); it should be noted that the STA2 and the STA3 send the corresponding first CTS message to the wireless AP and the STA1 The process of sending the first CTS message is the same.
  • step 11 STA1 determines the order of STA1 in all STAs in which the wireless AP is allowed to transmit uplink data according to the ULTA message.
  • FIG. 6 is a schematic diagram showing a preset flag setting of the AID MAP field.
  • the first bit, the third bit, and the fourth bit in the AID MAP field are preset tags "1", and all other bits are "0.”
  • the number of all preset tags in the AID MAP is three, that is, the wireless AP allows three STAs whose AIDs are 1, 3, and 4 to send uplink data.
  • the order of the preset tags of the first bit is the first, the order of the preset tags of the third bit is the second, and the order of the preset tags of the fourth bit is the third; that is, the STAs with the AID of 1 are in the three
  • the order in the STA is first, the order of the STAs with the AID of 3 is the second among the three STAs, and the order of the STAs with the AID of 4 is the third among the three STAs.
  • the STA with the AID of 4 is the STA1 in the embodiment
  • the STA with the AID of 3 is the STA2 in the embodiment
  • the STA whose the AID is 1 is the STA3.
  • Step 12 STA1 selects the TF domain of the corresponding order from the plurality of TF domains of the first CTS message to be transmitted according to the order to store the channel estimation information of STA1.
  • the mapping relationship between the order of the STAs in all STAs in which the wireless AP is allowed to transmit uplink data, and the order of the plurality of TF domains may be established in advance. In this way, after determining the order of STA1 in all STAs that are allowed to transmit uplink data, it may be possible to obtain multiple TF domains according to the mapping relationship. Select the corresponding coarse TF field.
  • the order of the plurality of TF fields may be consistent with the order of the STAs of all STAs that are allowed to transmit uplink data.
  • the STA (STA1) having the AID of 4 is the third in the order of the three STAs, and the STA1 selects the third TF field to store the channel estimation information
  • the STA (STA2) with the AID of 3 is The order of the three STAs is the second, and STA2 selects the second TF field to store the channel estimation information
  • the reverse order of the order of the preset tags corresponding to the STAs in the AID MAP domain in all the preset tags may be used as the order in which the STA selects the TF field, that is, the STA is allowed to send uplinks.
  • the reverse order of the order of all STAs of data coincides with the order of multiple TF fields.
  • the STA (STA1) with the AID of 4 has the third order in the three STAs, and the STA1 selects the first TF field to store the channel estimation information; the STA with the AID of 3 (STA2) is in the three.
  • the order in the STA is the second, STA2 selects the second TF field to store the channel estimation information; the STA (STA3) with the AID of 1 is the first in the three STAs, and the STA3 selects the third TF domain to store the channel. Estimated information.
  • Step 13) STA1 sends a first CTS message including channel estimation information of STA1, where STA1 transmits the channel estimation information in the first CTS message by using the entire channel resource, that is, STA1 transmits the first CTS message by using the entire channel resource.
  • STA1 can select a specific order of TF fields from a plurality of TF domains to store channel estimation information of STA1, similarly, STA2 (or STA3) can also select a specific order in multiple TF domains to be transmitted.
  • the TF field is used to store channel estimation information of STA2 (or STA3).
  • the order of the TF fields selected by STA1, STA2, and STA3 are different from each other, so that STA1, STA2, and STA3 can simultaneously transmit the TF field of the channel estimation information in the first CTS message in the entire channel resource.
  • the entire channel resource is a spectrum resource of the entire channel in which the wireless AP works, and the size of the spectrum resource may be multiple, for example, 20 MHz, 40 MHz, 80 MHz, 160 MHz, and the like. The following is an example in which the spectrum resource is 40 MHz.
  • the STA1 transmits the channel estimation information by using the entire channel resource, and may transmit the channel estimation information of the STA1 in a duplicate manner on each subchannel of the entire channel resource, that is, send on each subchannel. Same information (channel estimation letter of STA1) interest).
  • STA1 may directly transmit channel estimation information of STA1 by using the entire channel resource, that is, transmit a part of channel estimation information on each subchannel in the entire channel resource, and the information transmitted by all subchannels constitutes a complete Channel estimation information.
  • the subchannel is a set including one or more subcarriers.
  • Subchannels and subcarriers can be pre-divided and defined.
  • the 40 MHz channel is evenly divided into 512 subcarriers, and one or more subcarriers can be used as one subchannel.
  • every 32 subcarriers are used as one subchannel, so that the 40 MHz channel is divided into 16 subchannels in order from low to high, which are the first subchannel, the second subchannel, ..., the sixteenth subchannel.
  • the channel resources can also be divided into other numbers of subcarriers or subchannels.
  • the first CTS message of the STA1 may further include a data domain, where the data domain is used to store the uplink transmission information of the STA1, and the wireless AP may allocate the STA1 according to the uplink transmission information stored in the data domain and the transmission capability of the wireless AP.
  • the specific channel resource, the process in which the STA sends the first CTS message includes the following steps:
  • Step 14) STA1 determines, according to the order, a subchannel for transmitting a data field in the first CTS message in the entire channel resource, where the subchannel is a set including one or more subcarriers.
  • the order of the preset flag of the STA in all preset tags of the AID MAP domain corresponds to the order in which the STA transmits the subchannels used by the data field.
  • the mapping relationship between the order of the preset tags corresponding to the STAs in all the preset tags set in the AID MAP domain and the order of the STAs selecting the subchannels may be established in advance. After determining the order of the preset tags corresponding to the STAs in all the preset tags, the order in which the STA selects the TF fields may be determined according to the mapping relationship. The process of determining the order of the subchannels for transmitting the contents of the data domain is the same as the process of the STA selecting the TF domain, and details are not described herein again.
  • the STA of the AID of 4 (STA1) in FIG. 6 has the third order in all the preset flags of the AID MAP domain, and STA1 can select the content of the third subchannel transmission data field from the entire channel resource.
  • the STA1 transmits the content of the data field in the first CTS message corresponding to the STA1 by using the corresponding subchannel
  • the STA2 uses the subchannel corresponding to the STA to send the content of the data field in the first CTS message corresponding to the STA2.
  • the STA3 transmits the content of the data field in the first CTS message corresponding to the STA3 by using the corresponding subchannel.
  • STA1, STA2, and STA3 transmit the data fields in the respective first CTS messages in parallel using different subchannels.
  • STA1 transmits the channel estimation information of STA1 by using the entire channel resource in the time window corresponding to the selected TF field, and transmits the data field in the first CTS message on the corresponding subchannel.
  • STA2 or STA3 sends the first CTS message in the same manner as STA1 sends the first CTS message. Since STA1, STA2, and STA3 select different order of TF fields in which channel estimation information is stored, STA1, STA2, and STA3 have different timings for transmitting channel estimation information, and as a whole, STA1, STA2, and STA3 respectively correspond to three stages. A CTS message is sent in parallel.
  • the STA selects the TF field of the corresponding location according to the ULTA message to store its own channel estimation information, and transmits the content of the selected TF domain by using the entire channel.
  • the content of the data field in the first CTS message is sent by selecting the corresponding subchannel according to the ULTA message, that is, multiple STAs are sent to send the first CTS message in parallel.
  • FIG. 7 shows a schematic diagram of a transmission process of a first CTS message, including three STAs, which are STA1, STA2, and STA3, respectively.
  • the TF field in FIG. 7 is described by taking an LTF domain as an example. It is assumed that the order of "1" in the AID MAP field of STA1 is first, the order of "1" in the AID MAP field of STA2 is the second, and the order of "1" in the AID MAP field of STA3 is the first. And assume that the order of the STAs in all STAs that are allowed to transmit uplink data coincides with the order of multiple LTF domains.
  • STA1 selects the first LTF domain to store channel estimation information, the second and third LTF domains do not store any message, and transmit the LTF domain storing channel estimation information on the entire channel; meanwhile, STA1 selects the first subchannel.
  • Sending the content of the data field of the first CTS message similarly, STA2 selects the second LTF domain to transmit its own channel estimation information, and selects the second subchannel to transmit the content of the data domain;
  • STA3 selects the third LTF domain to transmit its own The channel estimates information and selects the content of the third subchannel to transmit the data field.
  • the wireless AP determines the channel of the STA1, the channel of the STA2, and the phase of the channel of the STA3 according to the channel estimation information of the STA1, the channel estimation information of the STA2, and the channel estimation information of the STA3. Relevant; depending on the correlation of the channels, S340 or S350 can be performed separately.
  • the radio AP calculates the channel reception matrix of the STA1 according to the channel estimation information in the TF domain in the first CTS message sent by the STA1, and performs channel estimation. Similarly, the wireless AP calculates the channel reception matrix of STA2 and STA3 for channel estimation. Then, based on the channel reception matrix of STA1, the channel reception matrix of STA2, and the channel reception matrix of STA3, the correlation of the channel of STA1, the channel of STA2, and the channel of STA3 is determined.
  • the wireless AP obtains the uplink transmission information of the STA1 according to the content of the data field in the first CTS message sent by the STA1, and the wireless AP allocates the channel resource to the STA1 according to the uplink transmission information of the STA1.
  • the wireless AP may allocate the same channel resource for STA1 and STA2, and allocate other channel resources for STA3. Then execute S360.
  • the wireless AP may allocate the same channel resource for STA1 and STA3, and allocate other channel resources for STA2. Then execute S360.
  • the wireless AP can perform other operations according to the channel correlation of the three STAs. For example, if the channels of STA1, STA2, and STA3 are not related to each other, the wireless AP may allocate the same channel resource for STA1, STA2, and STA3; or, if the channels of STA1, STA2, and STA3 are all related, the wireless AP may be STA1. STA2 and STA3 allocate channel resources different from each other.
  • the wireless AP sends a second message to STA1, STA2, and STA3, where the second message may include information about channel resources allocated for STA1, STA2, and STA3.
  • the wireless AP indicates to the STA the information of the channel resource allocated thereto through the second CTS message.
  • the second message may be a CTS message or an RTS message.
  • FIG. 8 is a schematic diagram of a message format of a second CTS message according to an embodiment of the present invention.
  • the MAC layer format of the second CTS message is from left to right: Frame Control, Duration field, AID (Association Identifier) field, Sub-Channel BIT MAP (subchannel bitmap) field, Time length (time length) field, and FCS (check) field.
  • AID Association Identifier
  • Sub-Channel BIT MAP subchannel bitmap
  • Time length time length
  • FCS check
  • the AID field stores the AID of the STA;
  • the Sub-Channel BIT MAP field stores the information of the channel resources allocated by the wireless AP for the STA, and the Sub-Channel BIT MAP field stores the binary number, each bit corresponding to one subchannel, Sub-Channel BIT MAP domain
  • the number of bits is not less than the number of subchannels, and the channel resources that can be used are indicated to the STA by a preset flag (for example, "1" or "0").
  • the Time length field stores the length of time that the wireless AP allocates channel resources for the STA.
  • STA1 sends uplink data according to the channel resource allocated by the wireless AP for STA1
  • STA2 sends uplink data according to the channel resource allocated by the wireless AP for STA2
  • STA3 sends uplink data according to the channel resource allocated by the wireless AP for STA3.
  • the STA1 and the STA2 simultaneously transmit the respective uplink data by using the same channel resource; if the channel resources allocated by the wireless AP to the STA1 and the STA2 are different, the STA1 and the STA2 use the respective channels. Resources send their own upstream data in parallel.
  • STA1, STA2, and STA3 send uplink data to the wireless AP.
  • the wireless AP first sends an ULTA message. After receiving the ULTA message, STA1, STA2, and STA3 send their respective first CTS messages in parallel. After receiving the first CTS message sent by each STA, the wireless AP determines whether the channels of the respective STAs are related according to the channel estimation information in the first CTS message of each STA. For example, the channel of STA2 is not related to the channel of STA3, and the channel of STA1 is related to the channel of STA2. Thus, STA2 and STA3 are allocated the same channel resources, and STA1 is allocated channel resources different from the channel resources of STA2 and STA3.
  • the wireless AP sends a second CTS message to each STA, and indicates a channel resource allocated to each STA through the second CTS message. After receiving the second CTS message, each STA uses the wireless AP to send uplink data (Data) to its allocated channel resource to implement parallel data transmission.
  • Data uplink data
  • STA2 and STA3 transmit uplink data (Data) using the same subchannel
  • STA1 transmits uplink data (Data) using subchannels different from the subchannels of STA2 and STA3.
  • the wireless AP determines the correlation of the channels of the multiple STAs according to the respective channel estimation information reported by the multiple STAs, and then the wireless AP may allocate the same for at least two STAs whose channels are not related to each other.
  • Channel resources so that the same channel is allocated The multiple STAs of the source use the same channel resource to send uplink data in parallel, that is, multiple STAs use the same time-frequency channel resource to transmit uplink data, thereby improving the utilization efficiency of channel resources in uplink transmission.
  • the uplink data transmission method can enable each STA to send the first CTS message in parallel, reducing the occupation time of the channel resource when the STA sends the first CTS message, and further improving the usage rate of the channel resource.
  • the wireless AP when the wireless AP sends the ULTA message, it does not determine whether the STA indicated in the ULTA message has uplink data to be sent. In order to enable the wireless AP to more accurately determine which STAs have uplink data to be transmitted, in FIG. 3 Based on the illustrated embodiment, the step of adding a wireless AP to query the STA for uplink data needs to be sent.
  • the method may further include the following steps before S310 of the embodiment shown in FIG. 3:
  • the wireless AP sends an uplink query (ULA, Up Link Announce) message to STA1, STA2, and STA3.
  • ULA uplink query
  • the ULA message is used to query whether STA1, STA2, and STA3 have uplink data to be sent. Then S420 is executed.
  • the uplink query message described in the embodiments of the present invention is only used to refer to a message sent by the wireless AP, and is not used to limit the message.
  • the uplink query message may be Other names, as long as they are used to query whether N STAs have uplink data to be sent.
  • the ULA message may be defined as an independent message, which is independently transmitted by the wireless AP in a broadcast manner or a multicast manner, and the MAC layer format of the ULA message is sequentially from left to right. It is: Frame Control, Duration, RA (Receive Address), TA (Transmitter Address), AID MAP, No. (Number of Sub-Carriers) Carrier number field, Sub-channel type field, and FCS (check) field.
  • the AID MAP field may contain a 2008 bit binary, and each bit corresponds to an STA whose AID is a corresponding value, which is the same as the AID MAP field in FIG. 4(a), and details are not described herein again.
  • the NoSC field stores the number of subcarriers (the number of channel resources) used by the STA to transmit an ULR (Up Link Request) message.
  • the Sub-channel type field is used to store the partition type of the subchannel, for example, 20 MHz, 40 MHz, 80MHz, 160MHz, or the number of subcarriers included in each subchannel.
  • the ULA may be defined as an information element, which is sent in other messages (for example, a beacon message Beacon), and the MAC layer format of the ULA message is from left to right.
  • the right is: Element (ID) ID field, Length (length) field, AID MAP field, NoSC field, and Sub-channel type field, where Element ID is the identification code of the information element, and Length field is used to indicate the information element.
  • Element ID is the identification code of the information element
  • Length field is used to indicate the information element.
  • the meanings of the information length, AID MAP domain, NoSC domain, and Sub-channel type domain have the same meanings as the same domain in FIG.
  • STA1 returns a ULR message to the wireless AP according to the received ULA message
  • STA2 returns a ULR message according to the received ULA message
  • STA3 returns an ULR message according to the received ULA message to the wireless AP.
  • the ULR message sent by STA1 includes information indicating whether STA1 has uplink data transmission.
  • the ULR message sent by STA2 includes information indicating whether STA2 has uplink data transmission.
  • the ULR message sent by STA3 includes information indicating whether STA2 has uplink data transmission. Then execute S430.
  • the uplink data transmission is performed by the STA1, the STA2, and the STA3 as an example.
  • the ULR message sent by the STA1 includes the information indicating that the STA1 has the uplink data transmission.
  • the ULR message sent by the STA2 includes the STA2 having the uplink data.
  • the information sent, the ULR message sent by STA2 contains information indicating that STA2 has uplink data transmission.
  • the wireless AP sends a ULA message to the N STAs, and after receiving the ULA message, the N STAs respectively return N ULR messages to the wireless AP, and each ULR message includes at least an indication to return the Whether the STA corresponding to the ULR message has uplink data transmission information.
  • the ULR message is a simple physical layer message, that is, directly modulating one or more binary information bits onto one or more subcarriers, wherein the subcarrier combination used by each STA is directly indicated by the AP in the ULA message.
  • the different values of the binary information indicate whether the STA has buffered uplink data to be sent, and optionally, the uplink data quantity information or the uplink channel resources required by the STA.
  • the ULR message when the ULR message carries the binary information "1111" (or "0000”), it indicates that the STA has uplink data to be sent; when the ULR message carries the binary information "0000" (or "1111"), it indicates that the STA does not need uplink data. send.
  • the wireless AP generates an ULTA message for instructing STA1, STA2, and STA3 to send uplink data according to the ULR message sent by STA1, STA2, and STA3.
  • the radio APs according to the ULR messages returned by the STAs, know which STAs have uplink data, and generate corresponding ULTA messages.
  • the content of the AID MAP field in the ULTA message indicates that the STAs that have uplink data transmissions are allowed to send uplink data.
  • the wireless AP sends a ULA message to query whether STA1, STA2, and STA3 have uplink data transmission. After receiving the ULA message, STA1, STA2, and STA3 respectively return a ULR message to the wireless AP to indicate whether there is uplink data transmission. The wireless AP determines the STAs that have uplink data transmission according to the respective ULR messages. In this example, STA1, STA2, and STA3 all have uplink data transmission, and then generate corresponding ULTA messages according to the respective ULRs and send them, and the subsequent message flow is shown in FIG. The process is the same and will not be repeated here.
  • the uplink data transmission method provided in this embodiment before the wireless AP sends the ULTA message, queries the STA whether the uplink data is sent by using the ULA message, so that the STA that sends the uplink data is determined according to the ULR message returned by the STA, and is generated in the ULTA message. Instructing the STA with the uplink data to send the indication information of the uplink data, so that the STA that is allowed to send the uplink data indicated by the radio AP in the ULTA message is consistent with the STA that needs to send the uplink data, and avoids that the STA that the wireless AP is allowed to send the uplink data does not need to be configured.
  • the problem of low efficiency of channel resource utilization occurs due to the transmission of uplink data, and the utilization efficiency of channel resources is improved.
  • the STA may send the first CTS message in a time division manner, and the application scenario of the wireless AP, STA1, STA2, and STA3 is taken as an example in this embodiment. Be explained.
  • the uplink data transmission method may include the following steps:
  • the wireless AP sends an ULTA message, where the ULTA message includes information for indicating that STA1, STA2, and STA3 are allowed to send uplink data.
  • the format of the ULTA message in this embodiment is the ULTA shown in FIG. 4(a) and FIG. 4(b).
  • the format of the message is the same and will not be described here.
  • the STA1 determines, according to the ULTA message, the time information that the STA1 sends the first CTS message, and the STA2 determines, according to the ULTA message, the time information that the STA2 sends the first CTS message, and the STA3 determines, according to the ULTA message, that the STA3 sends the first CTS message. Time information.
  • the data bit corresponding to the AID of the STA in the AID MAP field of the ULTA message is a preset flag (for example, binary "1” or "0"), it indicates that the wireless AP allows the STA to send uplink data, and corresponds to the STA's AID.
  • the order of "1" in all “1"s of the AID MAP field determines the order of time slots in which the first CTS message is transmitted by itself. The number of time slots is equal to the number of "1"s in the AID MAP field.
  • the order in which the data bit corresponding to the AID of the STA1 in the AID MAP domain is “1” is the second, and the STA1 may send the first CTS message corresponding to the STA1 in the second time slot.
  • the STA1 may send the first CTS message corresponding to the STA1 to the wireless AP by using the entire channel at the time indicated by the time information corresponding to the STA1, and the STA2 may send the entire channel to the wireless AP by using the time indicated by the time information corresponding to the STA2.
  • the first CTS message corresponding to the STA2, and the STA3 may use the entire channel to send the first CTS message corresponding to the STA3 to the wireless AP at the time indicated by the time information corresponding to the STA3.
  • the first CTS message sent by the STA1 includes at least the channel estimation information of the STA1.
  • the first CTS message sent by the STA2 includes at least the channel estimation information of the STA2
  • the first CTS message sent by the STA3 includes at least the channel estimation information of the STA3.
  • the first CTS message may further include uplink transmission information of the corresponding STA, so that the wireless AP allocates channel resources to the STA according to the channel estimation information and the uplink transmission information in the first CTS message.
  • the first CTS message in this embodiment differs from the first CTS message in the embodiment shown in FIG. 5 in that the first CTS message in this embodiment has only one TF field, and the other formats are the CTS messages shown in FIG. 5.
  • the format is the same and will not be described here.
  • the wireless AP determines the correlation between the channel of STA1, the channel of STA2, and the channel of STA3 according to the channel estimation information of STA1, the channel estimation information of STA2, and the channel estimation information of STA3. According to the correlation of the channel, S550 or S560 may be respectively performed. .
  • S550 When the channel of STA1 is not related to the channel of STA2, and the channel of STA1 is related to the channel of STA3, the wireless AP may allocate the same channel resource for STA1 and STA2, which is STA3. Allocate other channel resources. Then S570 is executed.
  • S560 When the channel of STA1 is related to the channel of STA2, and the channel of STA1 is not related to the channel of STA3, the wireless AP may allocate the same channel resource for STA1 and STA3, and allocate other channel resources for STA2. Then S570 is executed.
  • the wireless AP can perform other operations according to the channel correlation of the three STAs. For example, if the channels of STA1, STA2, and STA3 are not related to each other, the wireless AP may allocate the same channel resource for STA1, STA2, and STA3; or, if the channels of STA1, STA2, and STA3 are all related, the wireless AP may be STA1. STA2 and STA3 allocate channel resources different from each other.
  • the wireless AP sends a second message to STA1, STA2, and STA3, where the second message may include information about channel resources allocated for STA1, STA2, and STA3.
  • the wireless AP indicates to the STA the information of the channel resource allocated thereto through the second CTS message.
  • the STA1 sends the uplink data according to the channel resource allocated by the wireless AP to the STA1
  • the STA2 sends the uplink data according to the channel resource allocated by the wireless AP to the STA2
  • the STA3 sends the uplink data according to the channel resource allocated by the wireless AP to the STA3.
  • the S540 to S580 are the same as the S330 to S370 in the embodiment shown in FIG. 3, and details are not described herein again.
  • the STA of the wireless AP service includes three STAs of STA1, STA2, and STA3, and the wireless AP sends an ULTA message to STA1, STA2, and STA3, and STA1, STA2, and STA3 respectively send the corresponding first CTS according to the order indicated by the ULTA message.
  • STA1 transmits the first CTS message of STA1 in the first time window
  • STA2 transmits the first CTS message of STA2 in the second time window
  • STA3 transmits the first CTS message of STA3 in the third time window.
  • the wireless AP determines, according to the channel estimation information in each first CTS message, that the channel of STA2 is not related to the channel of STA3, and the channel of STA1 is related to the channel of STA2, and the same channel resource is allocated to STA2 and STA3, and is allocated to STA1. Independent channel resources. Then, the channel resources allocated for STA1, STA2, and STA3 are indicated by the second CTS message. After receiving the second CTS message, each STA uses the wireless AP to send uplink data for its allocated channel resource.
  • the wireless AP determines the correlation of the channels of the multiple STAs according to the respective channel estimation information reported by the multiple STAs, and then the wireless AP may allocate the same for at least two STAs whose channels are not related to each other.
  • the channel resources are such that multiple STAs that are allocated the same channel resource use the same channel resource to send uplink data in parallel, that is, multiple STAs use the same time-frequency channel resource to send uplink data, thereby improving the utilization efficiency of channel resources in uplink transmission.
  • the step of adding a wireless AP to query the STA for transmitting uplink data is added.
  • the uplink data transmission method may include the following steps:
  • the wireless AP sends a ULA message to STA1, STA2, and STA3, where the ULA message is used to query whether STA1, STA2, and STA3 have uplink data transmission.
  • STA1 returns a ULR message to the wireless AP according to the received ULA message
  • STA2 returns a ULR message according to the received ULA message
  • STA3 returns a ULR message according to the received ULA message to the wireless AP.
  • the ULR message sent by STA1 includes information indicating whether STA1 has uplink data transmission.
  • the ULR message sent by STA2 includes information indicating whether STA2 has uplink data transmission.
  • the ULR message sent by STA3 includes information indicating whether STA2 has uplink data transmission.
  • the wireless AP generates an ULTA message for instructing STA1, STA2, and STA3 to send uplink data according to the ULR message sent by STA1, STA2, and STA3.
  • the S510 to S580 are further executed.
  • the S510 to S580 refer to the related description in the corresponding embodiment of FIG. 14 , and details are not described herein again.
  • the STAs of the wireless AP service include three STAs, STA1, STA2, and STA3.
  • the wireless AP sends a ULA message to query whether STA1, STA2, and STA3 have uplink data transmission.
  • the wireless AP determines that STA1, STA2, and STA3 have uplink data transmission according to each ULR message. Then, the wireless AP generates a corresponding ULTA message according to the ULR and sends it.
  • the subsequent message flow is the same as the process shown in FIG. 14, and details are not described herein again.
  • the uplink data transmission method provided in this embodiment before the wireless AP sends the ULTA message, queries the STA whether the uplink data is sent by using the ULA message, so that the STA that sends the uplink data is determined according to the ULR message returned by the STA, and is generated in the ULTA message. Instructing the STA with the uplink data to send the indication information of the uplink data, so that the STA that is allowed to send the uplink data indicated by the radio AP in the ULTA message is consistent with the STA that needs to send the uplink data, and avoids that the STA that the wireless AP is allowed to send the uplink data does not need to be configured.
  • the problem of low efficiency of channel resource utilization occurs due to the transmission of uplink data, and the utilization efficiency of channel resources is improved.
  • the present invention can be implemented by means of software plus a necessary general hardware platform, and of course, can also be through hardware, but in many cases, the former is better.
  • Implementation Based on such understanding, the technical solution of the present invention, which is essential or contributes to the prior art, may be embodied in the form of a software product stored in a storage medium, including a plurality of instructions for causing a A computer device (which may be a personal computer, server, or network device, etc.) performs all or part of the steps of the methods described in various embodiments of the present invention.
  • the foregoing storage medium includes various types of media that can store program codes, such as a read only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.
  • the present invention further provides an uplink data transmission device.
  • the working principle and workflow of the uplink data transmission device refer to the foregoing method embodiments.
  • an uplink data transmission apparatus according to an embodiment of the present invention is shown.
  • the apparatus is applied to a first station (STA1).
  • STA1 first station
  • the apparatus may include: a receiving unit 110 and a sending Unit 120.
  • the receiving unit 110 is configured to receive an uplink transmission indication message sent by the wireless AP, where the uplink transmission indication message includes information used to indicate that the STA1 and the at least one other STA are allowed to send uplink data.
  • the sending unit 120 is configured to send, according to the uplink transmission indication message, a first message to the wireless AP, where the first message includes at least channel estimation information of the first STA, so that the wireless AP is configured according to the Determining, by the channel estimation information of the STA, the channel estimation information of the second STA, whether the channel of the first STA and the channel of the second STA are related, the second STA It is one of the at least one other STA.
  • the sending unit 120 is specifically configured to: when the second STA sends a third message to the wireless AP according to the uplink transmission indication message, the first STA according to the uplink transmission indication The message sends the first message to the wireless AP; the third message includes at least channel estimation information of the second STA.
  • the first message sent by the STA1 includes N training fields, where N is greater than or equal to the number of STAs in the uplink transmission indication message that are allowed to send uplink data, and one of the N training domains.
  • the training field is used to store channel estimation information of the first STA.
  • the method is specifically configured to: determine, according to the uplink transmission indication message, that the first STA is in the first STA and An order in at least one other STA; selecting a training field of a corresponding order from the N training domains according to the order to store channel estimation information of the first STA; transmitting a channel estimation information including the first STA a message, wherein the sending unit uses the entire channel resource to send the channel estimation information in the first message.
  • the first message includes a training field, and the training field is used to store channel estimation information of the first STA.
  • the uplink transmission indication message sent by the wireless AP further includes information indicating an order in which the first STA sends the first message.
  • the sending unit 120 When the sending unit 120 sends the first message to the wireless AP according to the uplink transmission indication message, the sending unit 120 is specifically configured to: send the first message to the wireless AP according to the sequence indicated by the uplink transmission indication message. .
  • the first message includes a training field, where the training field is used to store channel estimation information of the first STA, or the first message includes a data domain and a training domain, and the data domain And storing uplink transmission information of the first STA.
  • the method is specifically configured to: determine, according to the uplink transmission indication message, that the first STA is An order in the first STA and the at least one other STA; determining, according to the order, time information for transmitting the first message; transmitting, by using the entire channel resource, to the wireless AP at a time indicated by the time information The first message.
  • the sending unit 120 uses the entire channel resource to send the channel estimation information in the first message, specifically used in the entire channel resource.
  • Channel estimation information of the first STA is transmitted in parallel on each subchannel.
  • the sending unit 120 is configured to determine, according to the uplink transmission indication message, an order of the first STA in the first STA and the at least one other STA, where the sending unit is configured to: obtain the uplink transmission indication message. a preset flag corresponding to the association identifier of the first STA; the first STA determines an order of all preset markers indicated by the preset marker in the uplink transmission indication message, and determines the determined location The order is used as the order of the first STA in the first STA and the at least one other STA.
  • the first message further includes a data field for storing the uplink transmission information.
  • the sending unit 120 when the sending unit 120 sends the first message to the wireless AP according to the uplink transmission indication message, the sending unit 120 is further configured to: determine, according to the order, the entire channel resource used to send the first message. a subchannel of a data field, the subchannel being a set comprising one or more subcarriers; the data field in the first message is transmitted using the determined subchannel.
  • the receiving unit 110 is further configured to receive a second message sent by the wireless AP, where the second message includes information about a channel resource allocated by the wireless AP to the first STA;
  • the associated channel resources allocated by the first STA and the second STA are the same.
  • the sending unit 120 is further configured to send uplink data by using a channel resource allocated by the wireless AP.
  • the receiving unit 110 is further configured to receive an uplink query message sent by the wireless AP, where the uplink query message is used to query whether the first STA has uplink data transmission. information;
  • the sending unit 120 is further configured to: return an inquiry response message to the wireless AP, where the query response message includes at least information indicating that the first STA has uplink data transmission, so that the wireless AP responds according to the query.
  • the message generates the uplink transmission indication message.
  • the wireless AP determines whether the channels of the multiple STAs are related according to the channel estimation information of the STA, and allocates the same channel resources to the channels that are not related to the channel, so that the STAs with different channels are not related to the same channel resource. Transmitting uplink data, that is, multiple channel-unrelated STAs transmitting uplink data in parallel using the same time-frequency channel resource improves the utilization efficiency of channel resources (ie, spectrum) in uplink transmission.
  • channel resources ie, spectrum
  • FIG. 19 another uplink data transmission apparatus according to an embodiment of the present invention is shown.
  • the device is applied to a first station (STA1).
  • STA1 first station
  • the device may include a receiver 310, a transmitter 320, and a processor 330.
  • the receiver 310 and the transmitter 320 are used for communicating with the outside, the receiver 310 is for transmitting information to the outside, and the transmitter 320 is for receiving externally transmitted information.
  • the processor 330 is configured to receive, by the receiver 310, an uplink transmission indication message sent by the wireless access point, where the uplink transmission indication message includes information used to indicate that the first station and the at least one other station are allowed to send uplink data.
  • the processor 330 is further configured to send, by using the transmitter 320, the first message to the wireless access point according to the uplink transmission indication message, where the first message includes at least channel estimation information of the first station, so that the Determining, by the wireless access point, whether the channel of the first station and the channel of the second station are related according to channel estimation information of the first station and channel estimation information of the second station, where the second station is the at least One of the other sites;
  • the processor 330 is further configured to receive, by the receiver 310, a second message sent by the wireless access point, where the second message includes information about a channel resource allocated by the wireless access point to the first station;
  • the wireless access point allocates the same channel resources to the first station and the second station that are not related to the channel;
  • the processor 330 is further configured to send uplink data by using the channel resource allocated by the wireless access point by the transmitter 320.
  • the processor 330 may be configured to: when the processor 330 sends the first message to the wireless access point according to the uplink transmission indication message, the processor 330 may be configured to: at the second station, according to the uplink transmission indication message, And sending, by the wireless access point, the first message to the wireless access point by using the transmitter 320, according to the uplink transmission indication message, where the third message includes at least the second station. Channel estimation information.
  • the first message includes N training domains, where N is greater than or equal to the number of stations in the uplink transmission indication message that are allowed to send uplink data, and one training domain in the N training domains is used to store the Channel estimation information of the first station;
  • the processor 330 is configured to: when the processor sends the first message to the wireless access point according to the uplink transmission indication message, the processor 330 determines, according to the uplink transmission indication message, that the first site is in the first site and the The order in at least one other site; from the N according to the order Selecting a training field of the corresponding order in the training domain to store channel estimation information of the first station; selecting a training domain of the corresponding order from the N training domains according to the order, and storing channel estimation information of the first station; And transmitting, by the transmitter 320, a first message including channel estimation information of the first station, where the processor 330 may transmit the channel estimation information in the first message by using the entire channel resource by the transmitter 320.
  • the first message further includes a data field for storing the uplink transmission information.
  • the method is further configured to: determine, according to the sequence, the data field used in the first message to send the first message. a subchannel, the subchannel being a set comprising one or more subcarriers; the data field in the first message is transmitted by the transmitter 320 using the determined subchannel.
  • the processor 330 uses the entire channel resource to send the channel estimation information in the first message, specifically, the third station sends the first site in parallel through the transmitter 320 on each of the entire channel resources. Channel estimation information.
  • the determining, by the processor 330, the order of the first station in the first station and the at least one other station according to the uplink transmission indication message specifically: acquiring, in the uplink transmission indication message, Determining, by the associated identifier of the first site, a preset flag; determining an order of the preset tags in all preset tags indicated in the uplink transmission indication message, and using the determined sequence as the The order of a site in the first site and the at least one other site.
  • the method is specifically configured to: when the second station uses the channel resource allocated by the wireless access point to send uplink data, use The channel resources allocated by the wireless access point transmit uplink data through the transmitter 320.
  • the processor 330 is further configured to receive, by the receiver 310, an uplink query message sent by the wireless access point, where the uplink query message includes information used to query whether the first station has uplink data transmission;
  • the transmitter 320 returns a query response message to the wireless access point, where the query response message includes at least information indicating that the first station has uplink data transmission, so that the wireless access point generates according to the query response message.
  • the uplink transmission indication message is further configured to receive, by the receiver 310, an uplink query message sent by the wireless access point, where the uplink query message includes information used to query whether the first station has uplink data transmission;
  • the transmitter 320 returns a query response message to the wireless access point, where the query response message includes at least information indicating that the first station has uplink data transmission, so that the wireless access point generates according to the query response message.
  • the uplink transmission indication message is further configured to receive, by the receiver 310, an uplink query message sent by the wireless access point, where the uplink query message includes information used to query whether
  • the embodiment of the present invention further provides a channel resource allocation device.
  • a channel resource allocation device For the working principle and workflow of the channel resource allocation device, refer to the foregoing method embodiments.
  • a channel resource allocation apparatus according to an embodiment of the present invention is shown, where the apparatus is applied to a wireless AP, and the apparatus may include: a sending unit 210, a receiving unit 220, a channel estimating unit 230, and a channel resource. Distribution unit 240.
  • the sending unit 210 is configured to send an uplink transmission indication message, where the uplink transmission indication message includes information indicating that the N STAs are allowed to send uplink data, where N ⁇ 2, and N is an integer.
  • the receiving unit 220 is configured to receive N channel estimation information that are sent by the N STAs according to the uplink transmission indication message, respectively.
  • the channel estimation unit 230 is configured to determine, according to the received N channel estimation information, a correlation of channels of the N STAs;
  • the channel resource allocating unit 240 is configured to allocate, by using the same channel resource, at least two STAs that are not related to each other in the N STAs by using the same channel resource. Upstream data.
  • the channel resource allocation unit 240 is further configured to allocate different channel resources to at least two STAs related to the channel among the N STAs.
  • the sending unit 210 is further configured to send an uplink query message, where the uplink query message is used to query which STAs have uplink data to be sent.
  • the receiving unit 220 is further configured to receive N query response messages respectively returned by the N STAs, where each of the query response messages includes at least information indicating that the STA corresponding to the query response message has uplink data, so that The wireless AP generates the uplink transmission indication message according to the N query response messages respectively returned by the N STAs.
  • the receiving unit 220 may be a structure having a certain transmission function, such as a network element.
  • the channel resource allocation apparatus provided in this embodiment is applied to a wireless AP, and the ULTA message is sent to the STA by the sending unit.
  • a message including the self channel estimation information returned by the STA is received by the receiving unit.
  • the channel estimation unit determines whether the channel of STA1 and the channel of STA2 are related according to the channel estimation information of STA1 and the channel estimation information of STA2. If the channel of STA1 is not related to the channel of STA2, the channel resource allocation unit may allocate the same channel for STA1 and STA2.
  • the resources are used to enable STA1 and STA2 to use the same channel resource to transmit uplink data, that is, STA1 and STA2 can utilize the same time-frequency channel resource, thereby improving the utilization efficiency of channel resources in uplink transmission.
  • the apparatus is applied to a wireless AP, and the apparatus may include: a receiver 410, a transmitter 420, and a processor 430.
  • the receiver 410 and the transmitter 420 are used to communicate with the outside, the receiver 410 is used to transmit information to the outside, and the transmitter 420 is used to receive externally transmitted information.
  • the processor 430 is configured to send, by using the transmitter 420, an uplink transmission indication message, where the uplink transmission indication message includes information indicating that the N stations are allowed to send uplink data, N ⁇ 2, and N is an integer; Determining, by the N stations, N channel estimation information respectively according to the uplink transmission indication message; and determining, according to the received N channel estimation information, a correlation of channels of the N stations; and for the N sites At least two stations whose intermediate channels are uncorrelated are allocated the same channel resource, so that at least two stations whose channels are not related to each other simultaneously transmit uplink data by using the same channel resource.
  • the processor 430 is further configured to send, by using the transmitter 420, an uplink query message, where the uplink query message is used to query which stations have uplink data to be sent, and receive, by the receiver 410, the N returned by the N stations respectively.
  • Querying a response message each of the query response messages includes at least information indicating that the station corresponding to the query response message has uplink data transmission, so that the wireless access point returns the N according to the N stations respectively.
  • the query response message generates the uplink transmission indication message.
  • processor 430 is further configured to allocate different channel resources for at least two stations related to the channels in the N stations.
  • the embodiment of the present invention further provides a terminal device, which may include the uplink data transmission device shown in FIG. 18 or FIG. 19 above.
  • the terminal device may further include other modules in the general terminal device; for example, when the terminal device is a mobile phone, the terminal device may further include: a display screen, a gravity sensor, a memory, and the like.
  • the embodiment of the present invention further provides a wireless access device, which may include the channel resource allocation device shown in FIG. 20 or FIG. 21 above.
  • the wireless access device can access the wireless WAN and can provide wireless LAN.
  • the wireless access device can be a wireless router.
  • the wireless access device may also include some other modules or units common to the wireless router.
  • the invention may be described in the general context of computer-executable instructions executed by a computer, such as a program module.
  • program modules include routines, programs, objects, components, data structures, and the like that perform particular tasks or implement particular abstract data types.
  • the invention may also be practiced in distributed computing environments where tasks are performed by remote processing devices that are connected through a communication network.
  • program modules can be located in both local and remote computer storage media including storage devices.

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Quality & Reliability (AREA)
  • Mobile Radio Communication Systems (AREA)

Abstract

L'invention concerne un procédé et un dispositif de transmission de données en liaison montante. Le procédé comprend : selon les informations d'estimation de canal respectives rapportées par une pluralité de STA, la détermination, par un AP sans fil, de la corrélation de la pluralité de STA; puis l'attribution, par l'AP sans fil, de la même ressource de canal à au moins deux STA, dont les canaux n'ont pas de corrélation mutuelle, de sorte que la pluralité de STA auxquelles est attribuée la même ressource de canal utilisent la même ressource de canal pour envoyer des données en liaison montante en parallèle, c'est-à-dire que la pluralité de STA utilisent la même ressource de canal temps-fréquence pour envoyer des données en liaison montante, ce qui permet d'améliorer l'efficacité de l'utilisation d'une ressource de canal pendant une transmission en liaison montante.
PCT/CN2015/079994 2014-06-12 2015-05-27 Procédé et dispositif de transmission de données en liaison montante WO2015188698A1 (fr)

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EP3468077A4 (fr) * 2016-06-27 2019-06-19 Huawei Technologies Co., Ltd. Procédé et appareil de transmission de liaison montante
WO2018040046A1 (fr) * 2016-08-31 2018-03-08 华为技术有限公司 Procédé et appareil de mesure de canal

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CN112105068B (zh) * 2020-07-28 2021-11-19 华为技术有限公司 一种无线数据传输方法及其相关设备

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