Communication device and communication method

Abstract

A communication device that transmits a common response signal including data acquisition success or failure information for a plurality of links is provided. A communication device that performs wireless communication using a plurality of links includes a common data processing unit including a common storage unit of a cache type for storing acquisition success or failure information for packets received through the plurality of links, and performs common data processing on the packets received through the links, and a control unit that controls transmission of a response signal in response to the received packets. The control unit generates a common response signal including acquisition success or failure information for the plurality of links based on the acquisition success or failure information held by the common storage unit.

Description

Technical Field

[0001] The technology disclosed in this specification (hereinafter referred to as "this disclosure") relates to communication devices and communication methods for performing multi-link operations. Background Technology

[0002] To cope with the increase in data services in recent years, there is a need to increase data capacity and improve peak throughput in wireless local area networks (LANs). As a solution, multi-link operation (MLO) that performs communication by using multiple frequency bands simultaneously (see, for example, Patent Document 1) has attracted attention and is expected to be standardized by IEEE 802.11be, which is the next-generation standard of IEEE 802.11.

[0003] Furthermore, Automatic Repeat Request (ARQ) technology is known to achieve high reliability in data communication. That is, the data receiver returns a response signal including information on whether the data was successfully received, and the data sender retransmits the data based on the success or failure information extracted from the response signal. Typically, when a communication terminal attempts to issue a response signal on a link, it is assumed that the response signal is generated in the Media Access Control (MAC) block corresponding to that link in the communication terminal, and the response signal only includes information on whether the data was successfully received on the corresponding link (in other words, it does not include information on whether data was successfully received on other links). Under this assumption, for example, if the data sender fails to receive a response signal on a link, even if the data receiver successfully receives the data, the data sender determines that the data was not received correctly, resulting in the data receiver wasting time retransmitting the already received data.

[0004] Therefore, as an ARQ scheme in MLO, a scheme called Common Block Ack (CBA) has been proposed (see, for example, Non-Patent Literature 1). In this scheme, the data receiver transmits a CBA as a response signal to the data sender. This response signal includes not only information on whether data received on the same link was successfully acquired, but also information on whether data received on other links was successfully acquired. Therefore, if the data sender fails to receive the response signal on one link but successfully receives it on another, the data sender can obtain information on the success or failure of data transmission on the link where the response signal was not received, and can prevent unnecessary retransmissions.

[0005] In MLO, a sender can distribute data for the same service across multiple links and transmit the data. According to the common block acknowledgment scheme, the receiver transmits a response signal that collects information on the success or failure of data acquisition in a block acknowledgment session. Therefore, if the sender fails to receive individual response signals that include information on the success or failure of acquisition for each link, but successfully receives a common response signal that collects information on the success or failure of acquisition for the entire block acknowledgment session, unnecessary retransmissions can be prevented. Note that a block acknowledgment session includes a combination of the sender (sender address) and the service (Service Identifier (TID)). In this specification, the combination of the sender and the TID is also referred to as "sender information".

[0006] Generally, on the data receiver side, a memory called a "scoreboard" is used to store information on whether data acquisition was successful or not. In Non-Patent Document 1, a common scoreboard is used to generate common block acknowledgments, storing information on the success or failure of data acquisition received on each link. However, in the proposal described in Non-Patent Document 1, it is assumed that the common scoreboard manages the acquisition success or failure information as a "fully-state" common scoreboard, which allocates a fixed memory area for each block acknowledgment session (i.e., for each combination of sender and service identifier (TID), and it is necessary to install expensive memory with a large storage capacity, thus raising concerns about increased installation difficulty.

[0007] On the other hand, the "partial-state" scoreboard is primarily used to store information on the success or failure of data acquisition for each link. The partial-state scoreboard is a so-called small-capacity cache memory that temporarily stores acquisition success or failure information for at most one block acknowledgment session. That is, unlike the full-state scoreboard, the partial-state scoreboard does not allocate a fixed memory area for each block acknowledgment session, and the block acknowledgment session is overwritten when another block acknowledgment session begins on the corresponding link.

[0008] If a partially-state common scoreboard is used instead of a fully-state common scoreboard for management, storage capacity can be reduced, and installation complexity can be lowered. However, in a partially-state scoreboard, the success or failure information for a block acknowledgment session can only be guaranteed for storage at most. Therefore, unless update timing and conditions are specified, the common scoreboard can be overwritten by information from another session, leading to the problem of failing to generate common block acknowledgments.

[0009] Citation List

[0010] Patent documents

[0011] Patent Document 1: Japanese Patent Application Publication No. 2017-28746

[0012] Non-patent literature

[0013] Non-patent literature 1: Public submission to IEEE 802.11 (20 / 0055r0, Multi-link Block AckArchitecture) Summary of the Invention

[0014] The problem to be solved by the present invention

[0015] The purpose of this disclosure is to provide a communication device and a communication method for transmitting a common response signal that includes information on whether data acquisition of multiple links has been successful or not.

[0016] Solution to the problem

[0017] This disclosure was made in view of the above-mentioned problems, and its first aspect is a communication device for performing wireless communication using multiple links, the communication device comprising:

[0018] A common data processing unit includes a cache-type common storage unit that stores the success or failure of packet acquisition received on multiple links, and performs common data processing on packets received on each link; and

[0019] The control unit controls the transmission of response signals to received packets, wherein...

[0020] The control unit generates a common response signal that includes acquisition success or failure information received on multiple links, based on the acquisition success or failure information held in the common storage unit.

[0021] The communication device of the first aspect further includes an individual data processing unit, which includes an individual storage unit that stores information on whether packets received on the individual link were successfully acquired, and performs individual data processing on the packets received on the individual link.

[0022] The control unit performs update processing on the shared storage unit based on the success or failure information of retrieval related to the same sender information stored in both the shared storage unit and the individual storage units. That is, if the individual storage units store the same success or failure information of retrieval related to the same sender information as the shared storage units, the control unit performs update processing on the shared storage unit based on the success or failure information of retrieval related to the same sender information stored in the individual storage units.

[0023] Alternatively, the control unit performs update processing for the individual storage units based on whether the acquisition was successful or not, related to the same sender information stored in the common storage unit and the individual storage units.

[0024] Furthermore, a second aspect of this disclosure is a communication method for performing wireless communication using multiple links, the communication method comprising:

[0025] The common data processing step involves using a shared storage unit—a cache-type unit storing the success or failure of packet acquisition received on multiple links—to perform common data processing on packets received on each link; and

[0026] The control steps control the transmission of response signals to received packets, wherein...

[0027] In the control step, based on the acquisition success or failure information held in the common storage unit, a common response signal is generated that includes acquisition success or failure information received on multiple links.

[0028] Furthermore, a third aspect of the present invention is a communication device comprising:

[0029] Communication unit, using multiple links to perform wireless communication; and

[0030] The control unit controls the wireless communication operation in the communication unit, wherein...

[0031] When data signals are transmitted on multiple links, the control unit provides notification of the presence or absence of a common response signal, which includes information on whether the acquisition was successful or not related to the reception of data signals on the multiple links.

[0032] Furthermore, a fourth aspect of this disclosure is a communication method for performing wireless communication using multiple links, the communication method comprising:

[0033] The steps include providing notification of the presence or absence of a request for a common response signal and transmitting data signals, the common response signal including information regarding the success or failure of acquisition related to the reception of data signals on multiple links; and

[0034] The steps for receiving a response signal.

[0035] Effects of the present invention

[0036] According to this disclosure, it is possible to provide a communication device and a communication method that uses a cache-type shared storage unit to transmit a shared response signal, wherein the cache-type shared storage unit stores information on whether packets received on multiple links were successfully acquired.

[0037] It should be noted that the effects described in this specification are merely examples, and the effects of this disclosure are not limited thereto. Furthermore, in addition to the effects described above, this disclosure may provide additional effects.

[0038] Other objects, features, and advantages of this disclosure will become clear from a more detailed description based on the embodiments and accompanying drawings, which will be described later. Attached Figure Description

[0039] Figure 1 This is a diagram illustrating a configuration example of a communication system.

[0040] Figure 2 This is a diagram illustrating a configuration example of the communication device 200.

[0041] Figure 3 This is a diagram illustrating an example of MLD's functional configuration.

[0042] Figure 4 This is a diagram illustrating an example of multi-link operations.

[0043] Figure 5 This is a diagram illustrating another example of a multi-link operation.

[0044] Figure 6 This is a diagram illustrating an example of a communication sequence in an MLO-compatible communication system.

[0045] Figure 7 This is a diagram illustrating a configuration example for the "ADDBA Capability" field.

[0046] Figure 8 This is a flowchart illustrating the data transmission process performed by the STA during the data transmission phase.

[0047] Figure 9 This is a flowchart illustrating the processing steps performed by the AP during the data transmission phase (first example).

[0048] Figure 10 This is a diagram illustrating an example of the internal sequence when an AP receives data signals.

[0049] Figure 11 This is another example of a diagram illustrating the internal sequence of an AP receiving data signals.

[0050] Figure 12 This is a flowchart illustrating the AP transport block acknowledgment process (first example).

[0051] Figure 13 This is a diagram illustrating an example of the internal sequence during AP transport block acknowledgment.

[0052] Figure 14 This is another example of the internal sequence during AP transport block acknowledgment.

[0053] Figure 15 This is a diagram illustrating a configuration example of a block confirmation request frame.

[0054] Figure 16 This is a flowchart illustrating the process of the sender transmitting BAR frames.

[0055] Figure 17 This is a flowchart illustrating the processing procedure when the receiver receives a BAR frame.

[0056] Figure 18 This is a diagram illustrating an example of the internal sequence when a receiver receives a BAR frame.

[0057] Figure 19 This is a diagram illustrating an example (first example) of a communication sequence for multi-link operation.

[0058] Figure 20 The diagram shows the execution. Figure 19 The communication sequence shown is a diagram of the state of each scoreboard in the AP.

[0059] Figure 21 This is a diagram illustrating another example (the first example) of a communication sequence for multi-link operation.

[0060] Figure 22 The diagram shows the execution. Figure 21 The communication sequence shown is a diagram of the state of each scoreboard in the AP.

[0061] Figure 23 This is a diagram illustrating yet another example (the first example) of a communication sequence in a multi-link operation.

[0062] Figure 24 The diagram shows the execution. Figure 23 The communication sequence shown is a diagram of the state of each scoreboard in the AP.

[0063] Figure 25 This is a flowchart illustrating the processing steps performed by the AP during the data transmission phase (second example).

[0064] Figure 26 This is a diagram illustrating an example of the internal sequence of an AP when receiving data signals during the data transmission phase.

[0065] Figure 27 This is another example of the internal sequence of the AP when receiving data signals during the data transmission phase.

[0066] Figure 28 This is a flowchart illustrating the AP transport block acknowledgment process (second example).

[0067] Figure 29 This is a diagram illustrating yet another example (the second example) of a communication sequence in a multi-link operation.

[0068] Figure 30 The diagram shows the execution. Figure 29The communication sequence shown is a diagram of the state of each scoreboard in the AP. Detailed Implementation

[0069] In the following description, the technology according to this disclosure will be described in the following order with reference to the accompanying drawings.

[0070] A. System Configuration

[0071] B. Equipment Configuration

[0072] C.MLD Function Configuration Example

[0073] D. Common block confirmation

[0074] E. First Example

[0075] E-1. Overall Sequence

[0076] E-2. Block Confirmation Setup Phase

[0077] E-3. Data Transmission Phase

[0078] E-4. Block Confirmation Request Phase

[0079] E-5. Operation Example

[0080] F. Second Example

[0081] G. Effect

[0082] A. System Configuration

[0083] Figure 1 A schematic illustration shows a configuration example of an MLO-compatible communication system to which this disclosure is applied. The illustrated communication system includes a base station or access point (AP) and two slave devices STA (station) 1 and STA2 connected to the AP. For the sake of simplicity, Figure 1 Only two STAs are shown, but it is also assumed that three or more STAs are connected to one AP.

[0084] Data communication between AP and STA1, and between AP and STA2, can be achieved using two links, Link 1 and Link 2. Each of AP, STA1, and STA2 is an MLO-compatible communication device. In the following text, MLO-compatible communication devices are also referred to as "Multi-Link Devices (MLDs)".

[0085] Note that the term "link" as used in this specification refers to a wireless transmission path that enables data transfer between two communication devices. For example, selecting links from multiple independent wireless transmission paths (channels) divided according to frequency domain. Figure 1The two links used in the communication system shown use channels selected from multiple channels included in any frequency band such as the 2.4 GHz band, 5 GHz band, 6 GHz band, and 920 MHz band. Figure 1 The two links used in the communication system shown can be two channels selected from the same frequency band, or they can be two channels selected from different frequency bands. Furthermore, this includes [the following:] [the following is a list of components / mechanisms]... Figure 1 The frequency band of the channel selected by at least one of the two links used in the communication system shown can be a frequency band that is allowed for database access (such as a spectrum access system (SAS) - an unlicensed frequency band).

[0086] B. Equipment Configuration

[0087] Figure 2 The diagram illustrates an example of the internal configuration of communication device 200. Communication device 200 is an MLO-compliant communication device, and it is assumed that... Figure 1 The communication system shown operates as an AP, STA1, or STA2. The communication device 200 mainly includes a communication unit 210, a control unit 220, a storage unit 230, and an antenna 240. Furthermore, the communication unit 210 includes a communication control unit 211, a communication storage unit 212, a data processing unit including a common data processing unit 213 and an individual data processing unit 214, a signal processing unit 215, a wireless interface (IF) unit 216, and an amplification unit 217.

[0088] Each link is provided with an individual data processing unit 214, a signal processing unit 215, a wireless interface (IF) unit 216, an amplification unit 217, and an antenna 240. Assume that the communication device 200 uses two links, namely link 1 and link 2, to perform MLO. For example, individual data processing unit 214-1, signal processing unit 215-1, wireless interface unit 216-1, amplification unit 217-1, and antenna 240-1 are configured as one individual communication group for transmission / reception processing in link 1, and individual data processing unit 214-2, signal processing unit 215-2, wireless interface unit 216-2, amplification unit 217-2, and antenna 240-2 are configured as another individual communication group for transmission / reception processing in link 2.

[0089] The communication control unit 211 controls the operation of each unit in the communication unit 210 and the information transmission between the units. In addition, the communication control unit 211 performs control to transmit control and management information that it provides to another communication device to the data processing units (common data processing unit 213, individual data processing unit 214-1, and individual data processing unit 214-2).

[0090] The communication storage unit 212 stores information used by the communication control unit 211. Furthermore, the communication storage unit 212 stores data to be transmitted by the communication device 200 and data received by the communication device 200.

[0091] The data processing unit includes a common data processing unit 213 and an individual data processing unit 214. Furthermore, the individual data processing unit 214 includes individual data processing unit 214-1 and individual data processing unit 214-2 for individual links.

[0092] During transmission, the common data processing unit 213 performs sequence management, encryption processing, and other operations on the data stored in the communication storage unit 212 and the control and management information received from the communication control unit 211 to generate data units, and performs allocation to the respective data processing units 214-1 and 214-2. During reception, the common data processing unit 213 performs decryption and reordering processing on the data units.

[0093] In this disclosure, when a common block acknowledgment scheme is applied, the common data processing unit 213 performs data processing for transmitting common block acknowledgments, wherein the success or failure information of data acquisition in each block acknowledgment session (i.e., for each sender message) is collected using a partial-state or cached common scoreboard, and its details will be described later.

[0094] During transmission, individual data processing units 214-1 and 214-2 perform carrier-sensing-based channel access operations in the corresponding link, adding MAC headers and error detection codes to the data to be transmitted, and performing processing of multiple concatenated data units. During reception, individual data processing units 214-1 and 214-2 perform decoupling processing, analysis, and error detection of the MAC headers of the received data units, as well as performing retransmission request operations.

[0095] It should be noted that the operation of the common data processing unit 213 and the individual data processing units 214-1 and 214-2 is not limited to the above, and for example, one unit can perform the operation of the other unit.

[0096] During transmission, signal processing units 215-1 and 215-1-2 encode, interleave, and modulate the data units, and add a physical header to generate a symbol stream. Furthermore, during reception, signal processing units 215-1 and 215-2 analyze the physical header and perform demodulation, deinterleaving, and decoding on the symbol stream to generate data units. Moreover, signal processing units 215-1 and 215-2 estimate the characteristics of the complex channel and perform spatial separation processing when necessary.

[0097] During transmission, wireless interface units 216-1 and 216-2 perform digital-to-analog signal conversion, filtering, up-conversion, and phase control on the symbol stream to generate a transmitted signal. Furthermore, during reception, wireless interface units 216-1 and 216-2 perform down-conversion, filtering, and analog-to-digital signal conversion on the received signal to generate a symbol stream.

[0098] Amplification units 217-1 and 217-2 amplify signals input from wireless interface units 216-1 and 216-2 or antennas 240-1 and 240-2. A portion of amplification units 217-1 and 217-2 may be components other than communication unit 210. Furthermore, a portion of amplification units 217-1 and 217-2 may be included within wireless interface units 216-1 and 216-2.

[0099] Control unit 220 controls communication unit 210 and communication control unit 211. Furthermore, control unit 220 can alternatively perform some operations of communication control unit 211. Moreover, communication control unit 211 and control unit 220 can be configured as a single block.

[0100] Storage unit 230 holds information used by communication unit 210 and control unit 220. Furthermore, storage unit 230 can alternatively perform some operations of communication storage unit 212. Moreover, storage unit 230 and communication storage unit 212 can be configured as a single block.

[0101] Wireless communication is performed on link 1 by configuring individual data processing unit 214-1, signal processing unit 215-1, wireless interface unit 216-1, amplification unit 217-1, and antenna 240-1 into one individual communication group. Furthermore, wireless communication is performed on link 2 by configuring individual data processing unit 214-2, signal processing unit 215-2, wireless interface unit 216-2, amplification unit 217-2, and antenna 240-2 into another individual communication group. Although in Figure 2 Only two individual communication groups are depicted, but three or more groups can be components of communication device 200, and each of the individual communication groups can be configured to perform wireless communication on each link. Furthermore, storage unit 230 or communication storage unit 212 may be included in each of the individual communication groups.

[0102] A link is a wireless transmission path that enables data transmission between two communication devices, and each link is selected from, for example, multiple wireless transmission paths (channels) that are divided according to the frequency domain and are independent of each other. Links used by individual communication groups can be two channels selected from the same frequency band or two channels selected from different frequency bands. Furthermore, individual data processing units 214 and signal processing units 215 can be configured as a group, and two or more groups can be connected to a common wireless interface unit 216.

[0103] The wireless interface unit 216, the amplification unit 217, and the antenna 240 can be configured as a group, and two or more groups can be components of the communication device 200.

[0104] Communication unit 210 may also include one or more large-scale integrations (LSIs).

[0105] The common data processing unit 213 is also referred to as the "upper-layer MAC" or "high-level MAC," and the individual data processing unit 214 is also referred to as the "lower-layer MAC." Furthermore, the group of individual data processing units 214 and signal processing units 215 is also referred to as an "AP entity" or "non-AP entity." Alternatively, the group of individual data processing units 214 and signal processing units 215 may also be referred to as a "MAC entity," without distinguishing between AP and non-AP. The communication control unit 211 is also referred to as the "MLD management entity."

[0106] C.MLD Function Configuration Example

[0107] Figure 3 An example of the functional configuration of an MLO-compatible communication device (i.e., MLD) is illustrated. For simplicity, only the functional blocks relevant to this disclosure during data reception are shown here. Figure 3 In this context, the Link 1 MAC entity and the Link 2 MAC entity are functional blocks in individual data processing units 214-1 and 214-2, respectively, and the MLD entity is a functional block in the common data processing unit 213.

[0108] MAC addresses are assigned to each of the Link 1 MAC entity, Link 2 MAC entity, and MLD entity. The MAC address assigned to each link's MAC entity is used as the transmit or receive address for communication performed via Link 1 and Link 2. Furthermore, it is assumed that the MAC address assigned to the MLD entity is used during authentication or block acknowledgment session establishment.

[0109] Both the Link 1 MAC entity and the Link 2 MAC entity include a MAC Protocol Data Unit (A-MPDU) de-aggregation block, a MAC header + Cyclic Redundancy Code (CRC) verification block, and a link scoring block, which serve as functional blocks for performing MAC layer reception processing in the corresponding links.

[0110] The A-MPDU de-aggregation block performs the process of dividing the data signals transmitted through multiple packets (data units) aggregated into each packet.

[0111] The MAC header + CRC verification block reads the MAC header of each packet segmented by the A-MPDU de-aggregation block and checks the CRC of the entire packet. Within the block, the destination and type of the received packet (whether the signal is data or control) are identified from the information in the MAC header. Furthermore, the block determines whether the received packet was correctly acquired by checking the CRC. If the block determines that the received packet was correctly acquired, the information obtained from the packet's payload is transmitted to the upper layer. Conversely, if the block determines that the received packet was not correctly acquired, the received packet is discarded, and no information is transmitted to the upper layer.

[0112] The link scoring board stores the success or failure information for each packet acquisition, as determined in the MAC header + CRC checksum block, to generate block acknowledgments on the corresponding link. The link scoring board is a partially stateful scoring board, temporarily storing success or failure information for at most one block acknowledgment session. Details of the link scoring board will be described later.

[0113] The MLD entity comprises a block acknowledgment buffer and a record block, as well as a common scoring board, which serves as a functional block performing common processing across all links. Within the MLD, the common scoring board is used to perform data processing for transmitting common block acknowledgments, where information on the success or failure of data acquisition is collected for each block acknowledgment session (i.e., for each sender message).

[0114] To generate common block acknowledgments, the common scoreboard stores the success or failure of each packet acquisition, determined by the MAC header + CRC checksum block for each link. The common scoreboard is a partially-state scoreboard that temporarily stores success / failure information for at most one block acknowledgment session. Details of the common scoreboard will be described later.

[0115] The block acknowledgment buffer and record block temporarily store packets acquired through the MAC layer receive process performed by each link MAC entity, and perform reordering based on the sequence number assigned to each packet. Packets acquired by each link MAC entity are transmitted to the upper layer in ascending order of sequence number. In the event of a packet that cannot be acquired en route, the block acknowledgment buffer and record block temporarily store packets whose sequence numbers follow that packet's sequence number, without transmitting the packet to the upper layer. Furthermore, when an unacknowledged packet is retransmitted and can be acquired correctly, or when the data sender provides retransmission of packets without a block acknowledgment request, the buffer and record block transmit the temporarily stored packets to the upper layer.

[0116] In this embodiment, it is assumed that the link scoreboard included in each link MAC entity and the common scoreboard included in the MLD entity are managed as a partial-state scoreboard. The management of partial-state scoreboards is described in IEEE 802.11-2016 as follows, and this embodiment is also largely based on that description.

[0117] (1) The recipient must maintain a temporary block acknowledgment record.

[0118] (2) Store bitmap information and WindowStart in the temporary record. R (Minimum sequence number value in the bitmap), WindowEnd R (Maximum sequence number value in the bitmap), the address of the initiator (data sender), the service identifier (TID), and the WindowSize. R (Maximum transmission window size, a value determined at the block acknowledgment session described later), this information is associated with the sequence number.

[0119] (3) During partial-state operations, the receiver maintains the current record as long as it receives data from at least the same initiator.

[0120] (4) When data is received from another initiator or another TID (i.e., another sender information), existing temporary records may be discarded, such as by overwriting, if resources are needed to store temporary records for the new initiator and new TID (i.e., new sender information).

[0121] D. Common block confirmation

[0122] Figure 4 The illustration shows that in Figure 1 The example shown in the communication system illustrates a communication sequence in which STA1 uses Link 1 and Link 2 to perform data transmission and AP transmits a common block acknowledgment, serving as an example of multi-link operation.

[0123] Note that, Figure 4 The horizontal axis represents the time axis and indicates the communication operations at each time on each link between AP and STA1. Solid-lined rectangles represent transmitted frames corresponding to the communication device, link, and time; vertical solid-lined arrows indicate frame transmission to the destination; and dotted-lined rectangles represent received frames. Furthermore, for simplicity, it is assumed that… Figure 4 All TIDs of packets transmitted in STA1 are the same.

[0124] When STA1 acquires the transmission right on Link 1, STA1 transmits a data signal (A-MPDU) obtained by aggregating packets with sequence numbers #1 to #32. Upon receiving this data signal, AP transmits a block acknowledgment (BA) on Link 1 to STA1, including information on whether the packet acquisition was successful or not, containing information on whether the packet acquisition was successful or not. Note that since the packet acquisition success or failure information is indicated by bitmap format information, the packet acquisition success or failure information is also referred to as "bitmap information" below.

[0125] Furthermore, when STA1 acquires the transmission right on Link 2, STA1 transmits the data signal obtained by aggregating packets with sequence numbers #33 to #64. After STA1 has completed transmitting the data signal on Link 2, AP generates a block acknowledgment. At this time, since AP retains not only the bitmap information of the packets with sequence numbers #33 to #64 received on Link 2, but also the bitmap information of the packets with sequence numbers #1 to #32 received on Link 1, AP generates a common block acknowledgment including the bitmap information of sequence numbers #1 to #64, and transmits the common block acknowledgment to STA1 on Link 2.

[0126] If STA1 cannot correctly receive the block acknowledgments previously transmitted by AP on link 1, but can receive the common block acknowledgments transmitted by AP on link 2, then STA1 can obtain the bitmap information of all packets transmitted on each link and perform retransmission control in a way that does not retransmit unnecessary data.

[0127] It should be noted that, Figure 4 In the example of the communication sequence shown, it is assumed that the block acknowledgment transmitted by the AP on link 1 only provides notification of the bitmap information of the packets (#1 to #32) received on link 1. However, if a portion of the bitmap information of the packets (#33 to #64) received on link 2 can be obtained when generating the block acknowledgment, the AP can generate and transmit a common block acknowledgment on link 1.

[0128] Figure 5 The illustration shows that in Figure 1 Another example of a communication sequence of multi-link operations performed in the communication system shown. Figure 5 In the example of the communication sequence shown, STA1 uses Link 1 and Link 2 to perform data transmission, and STA2 uses Link 1 to perform data transmission to the AP.

[0129] Note that, Figure 5The horizontal axis represents the time axis and indicates the communication operations at each time on each link of AP, STA1, and STA2. Solid-lined rectangles represent transmitted frames corresponding to the communication device, link, and time; vertical solid-lined arrows indicate frame transmission to the destination; and dotted-lined rectangles represent received frames. Furthermore, for simplicity, it is assumed that… Figure 5 All TIDs of packets transmitted between STA1 and STA2 are the same.

[0130] When STA1 acquires the transmission right on Link 1, STA1 transmits a data signal obtained by aggregating packets with sequence numbers #1 to #32. Upon receiving this data signal, AP transmits a block acknowledgment to STA1 on Link 1, including bitmap information of the packets with sequence numbers #1 to #32. Furthermore, AP maintains the bitmap information of the packets with sequence numbers #1 to #32 in the common scoreboard to prepare for the generation of common block acknowledgments.

[0131] Furthermore, when STA1 acquires the transmission right on Link 2, STA1 transmits the data signal obtained by aggregating packets with sequence numbers #33 to #64. Here, before STA1 completes data transmission on Link 2, STA2 acquires the transmission right on Link 1 and transmits the data signal. When the AP receives the data signal from STA2, the bitmap information corresponding to the data received from STA2 is maintained in the common scoreboard in the AP and the link scoreboard of Link 1. In this case, since the bitmap information maintained in the common scoreboard corresponding to the packets received from STA1 differs in terms of initiator (or sender information), the bitmap information is likely to be deleted through overwriting or similar means. When STA1 finishes transmitting the data signal on Link 2, the AP does not maintain the bitmap information corresponding to the packets received from STA1 on any scoreboard, and therefore cannot transmit a common block acknowledgment to STA1.

[0132] When the common scoreboard is managed as a partial-state scoreboard in this manner, the opportunity for transmission common block acknowledgment is limited, especially for APs receiving data signals from multiple terminals on multiple links. Furthermore, a similar problem arises when the STA receives data signals associated with multiple TIDs.

[0133] Therefore, this disclosure provides appropriate update conditions and methods for a common scoreboard in MLO-compatible communication systems where the common scoreboard is managed as a partial-state scoreboard. According to this disclosure, communication devices that receive data signals from multiple terminals on multiple links (e.g., Figure 1 The AP in the middle can increase the chance of transmission common block confirmation and improve the reliability of ARQ.

[0134] E. First Example

[0135] In this section, a first example of a communication system to which this disclosure is applied will be described.

[0136] E-1. Overall Sequence

[0137] Figure 6 An example of a communication sequence implemented in a communication system to which this disclosure is applied is illustrated. Figure 6 In this context, we assume that the communication system is an MLO-compatible communication system, in which one AP and one STA are connected by using link 1 and link 2.

[0138] First, in the association phase (SEQ 601), an association process is performed between the AP and the STA, with the STA participating in the AP's Basic Service Set (BSS). In the IEEE 802.11 standard, the association process is performed by the STA transmitting an association request to the AP, and the AP transmitting an association response to the STA to provide a notification of the Association Identifier (AID).

[0139] Next, in the MLO setup phase (SEQ 602), the setup of Link 1 and Link 2 for communication between the AP and STA is performed. In this disclosure, at this phase, notification of the MAC addresses of the Link 1 MAC entity, Link 2 MAC entity, and MLD entity is provided between the AP and STA, and these are managed as a single sender (initiator). Note that the MLO setup phase can be included in the association phase.

[0140] Next, in the block acknowledgment setup phase (SEQ 603), the AP and STA exchange ADDBA (ADD Block Acknowledgment) request and response frames, and establish a block acknowledgment session. The information exchanged between the AP and STA includes the block acknowledgment policy, TID, buffer size, and the aforementioned Window Size. R (Window Start) R The size is determined by the size of the swap buffer.

[0141] The feature of this embodiment is that common scoreboard capability is included in both the ADDBA request frame and the ADDBA response frame. Since the STA exchanges indications with the AP during the block acknowledgment setup phase regarding whether to manage the common scoreboard capability, the STA can, for example, determine whether the AP can generate common block acknowledgments and correctly set the acknowledgment policy in the packet header. Details of the common scoreboard capability will be described later.

[0142] Next, in the data transmission phase (SEQ 604), the STA transmits data using Link 1 and Link 2, and the AP transmits block acknowledgments on Link 1 and Link 2. The STA, as the data sender, includes an acknowledgment policy in the packet header indicating which of the common block acknowledgments and regular acknowledgments is requested, and transmits the packet. This will be described in detail later. Furthermore, the method for updating the common scoreboard and the generation of common block acknowledgments in this phase will be described later.

[0143] Next, in the Block Acknowledgment Request (BAR) phase (SEQ 605), the STA transmits a Block Acknowledgment Request (BAR) frame to the AP on any link (link X). In response, the AP transmits a Block Acknowledgment frame on the same link (link X). The BAR frame is used not only when the STA wants to obtain block acknowledgment, but also to initialize the scoreboard and window Start between the AP and STA. R This is used when necessary. The method for updating the common scoreboard during the block confirmation request phase will be described later.

[0144] E-2. Block Confirmation Setup Phase

[0145] For reference Figure 6 During the block acknowledgment setup phase, the AP and STA exchange ADDBA (ADD Block Acknowledgment) request frames and response frames, and establish a block acknowledgment session.

[0146] Figure 7 The diagram illustrates a configuration example for the "ADDBA Capability" field, whose notifications are provided by ADDBA request frames and ADDBA response frames. Figure 7 In the example shown, notification of common scoreboard capability is provided by using a portion of the 5-bit reserved area (reserved bit) in the “ADDBA Capability” field (one bit in the example shown).

[0147] The data sender (initiator) can determine whether the receiver can manage bitmap information through the common scoreboard and whether it can generate common block acknowledgments based on information in the common scoreboard capability field. Therefore, the data sender (initiator) can correctly configure the acknowledgment strategy, for example, in the packet header.

[0148] Note that information about common scoreboard capabilities does not necessarily need to be included in the “ADDBA Capabilities” field and can be provided in the notification in the ADDBA request frame or ADDBA response frame.

[0149] E-3. Data Transmission Phase

[0150] For reference Figure 6 During the data transmission phase, the STA uses Link 1 and Link 2 to transmit data, and the AP transmits block acknowledgments on Link 1 and Link 2.

[0151] Figure 8 The flowchart illustrates the process by which the STA performs data transmission during the data transmission phase.

[0152] When the STA obtains the right to transmit (transmission opportunity: TXOP) by terminating backoff in a link (e.g., link 1) (step S801), the STA determines whether to request common block confirmation from the AP, which is the receiving side (step S802).

[0153] Upon requesting common block acknowledgment from the AP ("Yes" in step S802), the STA sets the acknowledgment policy in the "MAC Header / QoS Control" field attached to the packet header to "Common BA" (i.e., an acknowledgment response including information on whether data acquisition was successful across multiple links) and begins transmitting data signals (step S803). Since the STA is in the block acknowledgment setup phase (see...) Figure 6 and 7 The STA exchanges information with the AP indicating whether it can manage the common scoreboard (common scoreboard capability), so that, for example, the STA can determine whether the AP can generate common block acknowledgments and correctly set the acknowledgment policy in the header of the data packet.

[0154] On the other hand, if no common block acknowledgment is requested from the AP (No in step S802), for responses other than "common BA" (e.g., "normal acknowledgment"), the STA sets the acknowledgment policy in the "MAC header / QoS control" field attached to the packet header and begins transmitting data signals (step S804).

[0155] It is important to note that there are no particular restrictions on how the STA determines whether to request a common block acknowledgment in step S802. For example, the STA may request a common block acknowledgment only when transmitting data that requires low latency or high reliability, or it may be configured to always transmit a common block acknowledgment.

[0156] Figure 9 The flowchart illustrates the processing steps of the AP when receiving data during the data transmission phase.

[0157] The AP receives a data signal on a certain link (e.g., link 1) and updates the link scoreboard of the link MAC entity corresponding to that link using conventional methods based on the success or failure of data acquisition (step S901).

[0158] Next, the AP checks whether a common block acknowledgment (CBA) has been transmitted (step S902). Specifically, the AP checks whether it has completed block acknowledgment setup, including CBA, with the STA, which is the data sender (initiator), and whether the acknowledgment policy in the "MAC Header / QoS Control" field of the received packet is "Common BA". Since the STA has completed the block acknowledgment setup phase (see...), the AP checks whether the common block acknowledgment (CBA) has been transmitted. Figure 6 and 7 The STA exchanges information with the AP indicating whether it can manage the common scoreboard (common scoreboard capability), so that, for example, the STA can determine whether the AP can generate common block acknowledgments and correctly set the acknowledgment policy in the header of the data packet.

[0159] If the block acknowledgment settings with the data sender have not been completed or the acknowledgment policy in the "MAC header / QoS control" field of the received packet is not "common BA" ("No" in step S902), the AP ends this process without updating the common scoreboard.

[0160] On the other hand, if the block acknowledgment setup has been completed with the data sender and the acknowledgment policy in the "MAC header / QoS control" field of the received packet is "common BA" ("Yes" in step S902), the AP determines whether to update the common scoreboard.

[0161] As a determination of whether to update the common scoreboard, the AP first checks whether the link scoreboard of the link that has received data and the common scoreboard manage bitmaps with the same sender information (i.e., the same sender and the same TID) (step S903).

[0162] If the link scoreboard of a link that has already received data (e.g., link 1) and the common scoreboard manage a bitmap with the same sender and the same TID ("Yes" in step S903), the AP updates the bitmap information of the common scoreboard based on the bitmap information of the link 1 scoreboard of the link that has already received data (or the information of updating the SN of the bitmap therein) (step S905), and ends this process. Therefore, as long as data is continuously received from the same sender managed by the common scoreboard with the same TID, the acquisition success or failure information in the same block acknowledgment session is sequentially updated in the common scoreboard based on the acquisition success or failure information of the scoreboard of the link that has received data.

[0163] Alternatively, if the link scoreboard and common scoreboard of the link that has received data (e.g., link 1) do not manage bitmaps with the same sender and the same TID ("No" in step S903), the AP further checks whether the link scoreboard and common scoreboard of a link different from the link that has received data (e.g., link 2) manage bitmaps with the same sender and the same TID as the link scoreboard of the link that has received data on it (e.g., link 1) (step S904).

[0164] Then, if the link scoreboard management of another link has a bitmap with the same sender information (i.e., the same sender and the same TID) as the link scoreboard of the link that has received data ("Yes" in step S904), the AP creates and stores bitmap information with new sender information (i.e., new sender and new TID) in the common scoreboard based on the bitmap information of the link that has received data and the link scoreboard of each of the other links (step S906), and ends this process. As a result, when data with a different sender or TID than that managed by the common scoreboard is received (i.e., when the sender information is switched), in the common scoreboard, the acquisition success or failure information in the new block acknowledgment session is updated based on the acquisition success or failure information managed by the scoreboard for each link.

[0165] Alternatively, if the link scoreboard of another link does not manage a bitmap with the same sender information (i.e., the same sender and the same TID) as the link scoreboard of the link that has received data (No in step S904), the AP ends the current process without updating the common scoreboard.

[0166] Note that this embodiment assumes the link scoreboard and common scoreboard are updated when CRC checks are performed on packets aggregated across all used links; however, the timing of updating each scoreboard is not limited to this. For example, the link scoreboard can be updated when CRC checks on all packets aggregated across each link are completed. Furthermore, the common scoreboard can be updated at internally determined intervals, or it can be updated when all data signals have been received.

[0167] Furthermore, in this embodiment, it is assumed that the AP obtains the MAC address of each subordinate STA and stores and manages the MAC addresses of each link MAC entity and MLD entity for each sender (initiator) during the MLO setup phase. Therefore, the AP can determine whether the sender of each link is the same STA by checking the sender's address when receiving data on each link.

[0168] Figure 10 The illustration shows an example of the internal sequence when the AP receives a data signal during the data transmission phase. Figure 10 The diagram illustrates the interaction between the AP and the common scoreboard bitmap information when the AP updates the bitmap information based on the bitmap information of the Link 1 MAC scoreboard. Figure 9 An example of the internal sequence corresponding to step S905 in the flowchart shown. As described above, the AP is an MLO-compatible communication device, i.e., an MLD, and includes a Link 1 MAC entity and a Link 2 MAC entity that perform individual data processing for each link, as well as an MLD entity that performs common data processing for all links, such as... Figure 3 As shown in the figure. In addition, as a scoreboard for storing information on whether data acquisition was successful or not in the AP, a Link 1 scoreboard and a Link 2 scoreboard are provided, respectively included in the Link 1 MAC entity and the Link 2 MAC entity, as well as a common scoreboard included in the MLD entity.

[0169] When the Link 1 MAC entity updates the Link 1 scoreboard in response to receiving data on Link 1 (scoreboard update), the Link 1 MAC entity notifies the MLD entity of the scoreboard update information, which includes the initiator address, TID, and updated SN.

[0170] The MLD entity, based on information obtained from the Link 1 MAC entity, determines whether bitmap information with the same sender information (i.e., the same initiator address and the same TID) is managed by the common scoreboard (common scoreboard update decision 1). This determination process is related to... Figure 9 This corresponds to step S903 in the flowchart shown. Here, it is assumed that the block acknowledgment setup has been completed with the STA, which is the data sender (initiator), and that the acknowledgment policy in the "MAC Header / QoS Control" field of the received packet specifies "Common BA".

[0171] Then, if it is determined that the bitmap information with the same initiator address and TID as the Link 1 scoreboard is managed by the common scoreboard, the MLD entity updates the common scoreboard (common scoreboard update).

[0172] Assume the MLD entity updates the common scoreboard according to the following procedure. Note that the common scoreboard's WindowStart... R WindowEnd R and WindowSize R Described as WindowStart Rc WindowEnd Rc and WindowSize Rc Furthermore, when expanding the SN space, a value greater than 2 can be used. 11 The value.

[0173] (1) When WindowStart Rc≤SN≤WindowEnd Rc At that time, set "1" to the part corresponding to SN in the bitmap information of the common scoreboard.

[0174] (2) When WindowEnd Rc <SN≤WindowStart Rc +2 11 When this happens, perform the following processing.

[0175] (2-1) From WindowEnd Rc Set SN-1 to 0.

[0176] (2-2) Setting WindowStart Rc =SN-WindowSize Rc +1.

[0177] (2-3) Set WindowEnd Rc =SN.

[0178] (2-4) Set the part corresponding to SN in the bitmap information of the common scoreboard to "1".

[0179] In this embodiment, the common scoreboard is a partial state scoreboard and has only the capacity to store bitmap information in a single block acknowledgment session, and is overwritten by returning the header after one cycle. (1) WindowStart Rc ≤SN≤WindowEnd Rc The condition indicates that the corresponding SN falls within the window size of the common scoreboard, and in this case, the success or failure information of the acquisition of the group with that SN is set at the corresponding bit position in the bitmap of the common scoreboard. In addition, WindowEnd in (2) Rc <SN≤WindowStart Rc +2 11 The condition indicates that the window size of the common scoreboard has been reached, and in this case, the process returns to the header of the bitmap and sets the success or failure information for the group with this SN.

[0180] Figure 11 The illustration shows another example of the internal sequence when the AP receives a data signal during the data transmission phase. Figure 11 The illustration shows an example of the internal sequence corresponding to step S906 in the flowchart shown in 9 when the AP updates the bitmap information of the common scoreboard based on the bitmap information of the link 1 MAC scoreboard and the bitmap information of the link 2 scoreboard.

[0181] When the Link 1 MAC entity updates the Link 1 scoreboard in response to receiving data on Link 1 (scoreboard update), the Link 1 MAC entity notifies the MLD entity of the scoreboard update information, which includes the initiator address, TID, and updated SN.

[0182] The MLD entity determines, based on information obtained from the Link 1 MAC entity, whether bitmap information with the same initiator address and the same TID is managed by the common scoreboard (common scoreboard update decision 1). This determination process corresponds to step S903 in the flowchart shown in 9. Here, it is assumed that block acknowledgment settings have been completed with the STA as the data sender (initiator), and the acknowledgment policy in the "MAC header / QoS control" field of the received packet specifies "common BA".

[0183] Then, when it is detected that the common scoreboard and Link 1 scoreboard do not manage bitmap information with the same initiator address and the same TID, the MLD entity transmits a scoreboard initiator information request to the Link 2 MAC entity. The Link 2 MAC entity transmits a scoreboard initiator information response, including the initiator address and TID, in response to the request from the MLD entity. Note that if the MLD entity periodically obtains the initiator address and TID information from the Link 2 scoreboard, the MLD entity does not need to transmit a scoreboard initiator information request to the Link 2 MAC entity.

[0184] Based on information obtained from the Link 2 MAC entity, the MLD entity determines whether to update the common scoreboard (Common Scoreboard Update Decision 2) based on whether the common scoreboard manages bitmap information that has the same sender information (i.e., the same initiator address and the same TID) as the Link 1 and Link 2 scoreboards. This determination process is similar to... Figure 9 This corresponds to step S904 in the flowchart shown.

[0185] When both the Link 1 and Link 2 scoreboards manage bitmap information with the same sender information (i.e., the same initiator address and the same TID), the MLD entity determines to create bitmap information with a new sender (i.e., a new initiator address and a new TID) based on the bitmap information of the two scoreboards and updates the common scoreboard. Therefore, the MLD entity transmits a scoreboard request to both the Link 1 MAC entity and the Link 2 MAC entity.

[0186] Link 1 MAC entity and Link 2 MAC entity transmit scoreboard information, including bitmap information, WindowStart, WindowEnd, initiator address and TID, in response to scoreboard requests from MLD entity.

[0187] Then, the MLD entity updates the common scoreboard (common scoreboard update) according to the following procedure, based on the scoreboard information collected from the Link 1 MAC entity and the Link 2 MAC entity. Note that here, the WindowStart of the Link X (the Xth link) scoreboard is... R WindowEnd R and WindowSize R Described as WindowStart Rx WindowEnd Rx and WindowSize Rx .

[0188] (1) Set WindowEnd Rc =max(WindowEND) R1 WindowEND R2 That is, the common scoreboard is updated based on the larger of the final values ​​of the sequence numbers to be stored in the link 1 scoreboard and the link 2 scoreboard.

[0189] (2) Set WindowStart Rc =WindowEnd Rc -WindowSize Rc +1.

[0190] (3) Using WindowStart Rc Starting from WindowEnd Rc Create WindowSize using the endpoint (first enter 0). Rc Bitmap of dimensions.

[0191] (4) From WindowStart R To WindowEnd Rc In each SN, if the bitmap information of Link 1 or Link 2 is "1", then "1" is set in the part of the corresponding SN indication in the bitmap information of the common scoring board. That is, for an SN that indicates successful packet acquisition in at least one of the Link 1 scoring board or Link 2 scoring board, "1" indicating successful packet acquisition is also set in the bitmap information of the common scoring board.

[0192] Furthermore, if the sum of the window sizes of the link scoreboards across all links exceeds the window size of the common scoreboard, some bitmap information may be corrupted during the process described above when the common scoreboard is updated. In this case, the MLD entity can instruct that common block acknowledgments not be sent to links where bitmap information cannot be stored in the common scoreboard, and can instruct the transmission of ordinary block acknowledgments based on the information from the link scoreboard for each link.

[0193] Furthermore, after updating the bitmap information, the common scoreboard can update the link scoreboard for each link based on the bitmap information of the common scoreboard. Specifically, in an SN that is set to "1" in the common scoreboard and set to "0" in the link scoreboard, control can be performed by setting "1" in the corresponding part of the link scoreboard, while maintaining the WindowStart and WindowEnd for each link.

[0194] Figure 12 The flowchart illustrates the process of AP transport block acknowledgment.

[0195] After receiving the data signal on a certain link (e.g., link 1) (step S1201), the AP checks whether the common scoreboard manages a bitmap with the same sender and the same TID as the sender of the data signal (step S1202).

[0196] Then, if the common scoreboard management has a bitmap with the same sender and the same TID as the sender of the data signal ("Yes" in step S1202), the AP generates a common block acknowledgment based on the information of the common scoreboard, transmits the common block acknowledgment to the STA as the sender (step S1203), and ends this process.

[0197] On the other hand, if the common scoring board does not manage bitmaps with the same sender and the same TID as the sender of the data signal ("No" in step S1202), the AP generates a regular block acknowledgment based on the information of the link scoring board of the link that received the data signal (e.g., link 1), sends a transmission block acknowledgment to the STA as the sender (step S1204), and ends this process.

[0198] Figure 13 The illustration shows an example of the internal sequence when an AP transport block is acknowledged. Figure 13 The diagram illustrates the interaction between the AP and the common block acknowledgment during bitmap information transmission based on the common scoring board. Figure 12 The flowchart shown is an example of the internal sequence corresponding to step S1203. The MLO-compatible AP includes a Link 1 MAC entity and a Link 2 MAC entity that perform individual data processing for each link, and an MLD entity that performs common data processing for all links. Furthermore, as a scoreboard for storing data acquisition success or failure information in the AP, a Link 1 scoreboard and a Link 2 scoreboard are provided, respectively included in the Link 1 MAC entity and the Link 2 MAC entity, and a common scoreboard is included in the MLD entity.

[0199] After receiving the data signal on Link 1 (data Rx ends), the Link 1 MAC entity notifies the MLD entity of the common block acknowledgment request information, including the initiator address and TID.

[0200] Based on the information from the common block acknowledgment request obtained from the Link 1 MAC entity, the MLD entity checks that bitmap information with the same initiator and TID as the sender of the data received on Link 1 is managed by the common scoreboard, and notifies the Link 1 MAC entity that this includes common scoreboard information (at least bitmap information, WindowStart). Rc WindowEnd Rc The common block confirmation response information.

[0201] The Link 1 MAC entity generates a common block acknowledgment (generate block acknowledgment) based on the acquired common block acknowledgment response information and transmits the common block acknowledgment to the STA (start block acknowledgment Tx) that is the sender.

[0202] Figure 14 The illustration shows another example of the internal sequence when the AP transport block is acknowledged. Figure 14 The diagram illustrates the interaction between the AP and the regular block acknowledgment when the AP transmits bitmap information based on the link scoring board. Figure 12 An example of the internal sequence corresponding to step S1204 in the flowchart shown.

[0203] After receiving the data signal on Link 1 (data Rx ends), the Link 1 MAC entity notifies the MLD entity of the common block acknowledgment request information, including the initiator address and TID.

[0204] Based on the information obtained from the common block acknowledgment request information from the Link 1 MAC entity, the MLD entity checks that bitmap information with the same initiator and the same TID as the sender of the data received on Link 1 is not managed by the common scoreboard, and notifies the Link 1 MAC entity of the common block acknowledgment response information that does not include the common scoreboard information.

[0205] The Link 1 MAC entity generates a regular block acknowledgment (generate block acknowledgment) based on the Link 1 scoreboard information of the Link 1 MAC entity, and transmits the block acknowledgment to the STA as the sender (start block acknowledgment Tx).

[0206] E-4. Block Confirmation Request Phase

[0207] Next, in the block acknowledgment request phase, the STA transmits a Block Acknowledgment Request (BAR) frame to the AP on any link (link X). In response, the AP transmits a block acknowledgment frame on the same link (link X). The BAR frame is used not only when the STA wants to obtain block acknowledgment, but also to initialize the scoreboard and window Start between the AP and STA. R Use when needed.

[0208] Figure 15The diagram illustrates a configuration example for a Block Acknowledgment Request (BAR) frame. (See reference...) Figure 6 The BAR frame is transmitted by the sender (STA) to request the receiver (AP) to acknowledge the transport block.

[0209] Since the structure of the BAR frame is specified in IEEE 802.11, its detailed description is omitted here. A feature of this embodiment is that the "Common Scoreboard Update" subfield is included within the "BAR Control" field. Specifically, one bit of the "Reserved" field in the "BAR Control" field is allocated to the "Common Scoreboard Update" subfield.

[0210] When a sender requests bitmap information of the receiver's common scoreboard while transmitting a BAR frame on any link, the sender sets "1" in the "Common Scoreboard Update" subfield and transmits the BAR frame. Note that if the sender wishes to update only the receiver's common scoreboard, the sender can set the receiver address (RA) of the BAR frame to the MAC address of the MLD entity assigned to the receiver and transmit the BA frame.

[0211] Figure 16 The flowchart illustrates the process when the sender transmits a BAR frame. Here, it is assumed that the sender is a STA that has already transmitted a data frame to the AP.

[0212] When a BAR is transmitted on a link (e.g., link 1) (step S1601), the STA determines whether to request an update of the common scoreboard at the same time as the link scoreboard (step S1602).

[0213] Then, in the case of requesting an update to the common scoreboard ("Yes" in step S1602), the STA sets "1" in the "Common Block Confirmation Update" subfield of the BAR frame and transmits the BAR frame (step S1603).

[0214] On the other hand, if no update of the common scoreboard is requested ("No" in step S1602), the STA sets "0" in the "Common Block Confirmation Update" subfield of the BAR frame and transmits the BAR frame (step S1604).

[0215] Figure 17 The flowchart illustrates the processing when the receiver receives a BAR frame. Here, it is assumed that the receiver is an AP that has already received a data frame from the STA.

[0216] When the AP receives a BAR frame on a link (e.g., link 1) (step S1701), the AP updates the link scoreboard corresponding to the link that received the BAR (step S1702).

[0217] Next, the AP checks whether the “Common Scoreboard Update” subfield of the BAR frame received in step S1701 is set to “1” (step S1703).

[0218] Then, if "1" is set in the "Common Scoreboard Update" subfield ("Yes" in step S1703), the AP updates the common scoreboard (step S1704), and then the transport block is confirmed (step S1705). According to, for example, with... Figure 9 The data reception process shown is similar to the process used to update the common scoreboard.

[0219] On the other hand, if the "Common Scoreboard Update" subfield is set to "0" ("No" in step S1703), the AP transport block acknowledges without updating the common scoreboard (step S1705).

[0220] Figure 18 The illustration shows an example of the internal sequence when the receiver receives a BAR frame. Figure 18 With Figure 17 The flowchart shown corresponds to the case where the common scoreboard update is 1 in step S1703, and therefore the common scoreboard is updated in step S1704. Here, it is assumed that the AP, as the receiver, receives a BAR frame on link 1 and then transmits a block acknowledgment on link 1. The AP is an MLO-compatible communication device, i.e., an MLD, and includes a link 1 MAC entity and a link 2 MAC entity that perform individual data processing for each link, as well as an MLD entity that performs common data processing for all links, such as... Figure 3 As shown in the image.

[0221] When the processing of received BAR frames is completed (BAR Rx ends), the Link 1 MAC entity updates the Link 1 scoreboard of the Link 1 MAC entity (scoreboard update).

[0222] Next, when the “Common Scoreboard Update” subfield of the BAR frame is found to be set to “1”, the Link 1 MAC entity will transmit a Common Scoreboard Update request, including the initiator address, TID and start sequence number (SSN), to the MLD entity.

[0223] The MLD entity updates the common scoreboard based on the information included in the common scoreboard update request from the Link 1 MAC entity (common scoreboard update). Subsequently, the MLD entity transmits a common block acknowledgment response frame to the Link 1 MAC entity, including common scoreboard information (bitmap information), WindowStart, WindowSize, initiator address, and TID.

[0224] The Link 1 MAC entity generates a block acknowledgment (Generate Block Acknowledgment) based on the information included in the common block acknowledgment response from the AP, and begins transmitting block acknowledgments (Start Block Acknowledgment Tx).

[0225] Here, when updating the scoreboard in response to a block confirmation request, the following rules are applied to both the Link 1 scoreboard and the common scoreboard.

[0226] <For BARs with the same sender and the same TID>

[0227] (1) WindowStart R ≤SSN≤WindowEnd R situation

[0228] (1-1) Setting WindowStart R =SSN

[0229] (1-2) will be from WindowEnd R +1 to WindowStart R +WindowSize R The bitmap for -1 is set to "0".

[0230] (1-3) Set WindowEnd R =WindowStart R +WindowSize R -1

[0231] (2)WindowEnd R <SN≤WindowStart R +2 11 situation

[0232] (2-1) Setting WindowStart R =SSN

[0233] (2-2) Set WindowEnd R =WindowStart R +WindowSize R -1

[0234] (2-3) will start from WindowStart R To WindowEnd Rc The bitmap is set to "0".

[0235] (3) If WindowStart Rc +2 11 <SN≤WindowStart Rc So, don't update.

[0236] <For the case of a BAR from another sender or another TID>

[0237] (1) Set WindowStart R =SSN

[0238] (2) From WindowEnd R +1 to WindowStart R +WindowSize R The bitmap for -1 is set to "0".

[0239] (3) Using WindowStart R Starting from and using WindowEnd R Create WindowSize in the manner of endpoint R Bitmap of dimensions.

[0240] E-5. Operation Example

[0241] In the first example, the generation of common block acknowledgments is implemented in an MLO-compatible communication system based on a partial-state common scoreboard. An operational example from the first example will be described in this section.

[0242] Figure 19 The illustration shows that in Figure 1 The example shown is a communication sequence of multi-link operations performed in a communication system. Figure 19 In the example of the communication sequence shown, STA1 and STA2 use Link 1 and Link 2 to perform data transmission to the AP.

[0243] Note that, Figure 19 The horizontal axis represents the time axis and indicates the communication operations at each time on each link of AP, STA1, and STA2. Solid-lined squares represent transmitted frames corresponding to the communication device, link, and time; vertical solid-lined arrows indicate frame transmission to the destination; and dotted-lined squares represent received frames.

[0244] also, Figure 20 The diagram illustrates when execution Figure 19 The communication sequence shown is a symbolic representation of the bitmap information of the Link 1 MAC entity and common scoreboard for each link in the AP at each time (T1 to T8). The Link 1 MAC entity and common scoreboard for each link are part-state cache memories, where a block acknowledgment of packet retrieval success or failure information within a session can be temporarily stored. WindowStart R The information matching the indicated SN is stored at the left end of the bitmap information for each scoreboard, while WindowEnd RThe information matching the indicated SN is stored at the right end. At each bit position of each bitmap information, 0 and 1 represent whether the packet with the corresponding SN was successfully acquired. The SN of a packet that has not yet been received is represented by "0". Furthermore, the SN of a packet that has been acquired is represented by "X", and it is assumed that 0 or 1 is stored in X depending on whether the packet acquisition was successful or failed.

[0245] exist Figure 20 In this example, assuming WindowSize = 64, in STA1 and STA2, packets SN#1 to #32 are transmitted on link 1, and data SN#33 to #64 are transmitted on link 2 (i.e., assuming that each of STA1 and STA2 distributes and transmits a number of packets corresponding to the window size to links 1 and 2). However, this disclosure is not limited to the above assumptions, and for example, different numbers of packets may be included in links 1 and 2, or a number of packets smaller than WindowSize may be transmitted.

[0246] Furthermore, generally speaking, when TIDs differ even for the same sender (initiator address), the scoreboard manages the different sender information as a separate acknowledgment session. Figure 19 and 20 In this context, for the sake of simplicity, it is assumed that only data with the same TID is transmitted from each sender (STA1, STA2), and that the session is managed as a block acknowledgment by the scoreboard.

[0247] In the following text, reference will be made to Figure 20 The state of each scoreboard shown is used to describe Figure 19 The communication sequence shown in .

[0248] When STA1 acquires the transmission right of Link 1 at time T1, it begins transmitting the data signal obtained by aggregating packets with SN#1 to #32, and completes the transmission of the aggregated data signal at time T3. During the period from time T1 to time T3, bitmap information related to the success or failure of acquiring packets with SN#1 to #32 transmitted from STA1 is stored in the Link 1 scoreboard and updated sequentially.

[0249] Furthermore, when STA1 acquires the transmission right for Link 2 at time T2, it begins transmitting data signals obtained by aggregating packets with the same TID as Link 1 and SN#33 to #64, and completes the transmission of the aggregated data signals at time T5. During the period from time T2 to time T5, bitmap information related to the success or failure of acquiring packets with SN#33 to #64 transmitted from STA1 is stored in the Link 2 scoreboard and updated sequentially.

[0250] On the other hand, STA2 acquires the transmission right of Link 1 at time T4. That is, at time T4, the sender on Link 1 changes from STA1 to STA2. STA2 begins transmitting the data signal obtained by aggregating packets with SN#1 to #32, and completes the transmission of the aggregated data signal at time T7. After time T4, bitmap information related to the success or failure of acquiring packets with SN#1 to #32 transmitted from STA2 is stored in the Link 1 scoreboard and updated sequentially.

[0251] Additionally, STA2 acquires the transmission rights for Link 2 at time T6. That is, at time T6, the sender on Link 2 changes from STA1 to STA2. STA2 begins transmitting data signals on Link 2 by aggregating packets with the same TID as Link 1 and SN#33 to #64, and completes the transmission of the aggregated data signals at time T8. After time T6, bitmap information related to the success or failure of acquiring packets with SN#33 to #64 transmitted from STA2 is stored in the Link 2 scoreboard and updated sequentially.

[0252] AP's MLD entities update the common scoreboard according to the above update rules.

[0253] Therefore, the AP receives data signals from STA1 on both Link 1 and Link 2, and at time T2 when both the Link 1 scoreboard and the Link 1 scoreboard manage the bitmap information of STA1 with the same sender and the same TID, the AP updates the common scoreboard and stores the bitmap information related to whether the packet from STA1 was successfully acquired.

[0254] Then, even after time T4 when the sender on link 1 changes from STA1 to STA2, bitmap information related to the success or failure of packet acquisition from STA1 is also stored in the link 2 scoreboard. Therefore, during the period from time T2 to T5, bitmap information related to the success or failure of packet acquisition from STA1 is continuously updated in the common scoreboard. As a result, at time T5 when STA1 finishes data transmission on link 2, bitmap information related to the success or failure of acquisition of packets with SN#1 to #64 transmitted from STA1 on both link 1 and link 2 (i.e., information on the successful or failure of the sender and TID acquisition) is stored in the common scoreboard. Therefore, the AP can... Figure 12 The block acknowledgment transmission process shown transmits common block acknowledgments to STA1 on link 2.

[0255] On the other hand, at time T6, the AP receives data signals from STA2 on both Link 1 and Link 2, and both Link 1 and Link 2 scoreboards manage the bitmap information of STA2, which has the same sender and the same TID. Therefore, a handover is performed in a manner that stores bitmap information related to the success or failure of packet acquisition from STA2 in a common scoreboard. During the period from time T6 to time T8, the bitmap information related to the success or failure of packet acquisition from STA2 is continuously updated in the common scoreboard. At this time, depending on the storage capacity of the common scoreboard, the bitmap information related to STA1 stored so far is deleted (as in this embodiment, assuming the common scoreboard is a partial-state cache memory capable of storing packet acquisition success or failure information in a block acknowledgment session, the bitmap information related to STA1 is deleted by overwriting).

[0256] Subsequently, at time T8, when STA2 finishes data transmission on link 2, bitmap information related to the success or failure of acquiring packets with SN#1 to #64 transmitted from STA2 on links 1 and 2 (i.e., information on the successful acquisition of the sender and TID) is stored in the common scoring board. Therefore, the AP can... Figure 12 The block acknowledgment transmission process shown transmits common block acknowledgments to STA2 on link 2.

[0257] Figure 21 The illustration shows that in Figure 1 This is another example of a communication sequence of multi-link operations performed in the communication system shown. Furthermore, Figure 22 The diagram illustrates the execution Figure 21 The communication sequence shown illustrates the state of each scoreboard in the AP at each time point.

[0258] When STA1 acquires the transmission right of Link 1 at time T1, it begins transmitting the data signal obtained by aggregating packets with SN#1 to #32, and completes the transmission of the aggregated data signal at time T5. During the period from time T1 to time T5, bitmap information related to the success or failure of acquiring packets with SN#1 to #32 transmitted from STA1 is stored in the Link 1 scoreboard and updated sequentially.

[0259] Furthermore, when STA1 acquires the transmission right for Link 2 at time T2, it begins transmitting the data signal obtained by aggregating packets with the same TID as Link 1 and SN#33 to #64, and completes the transmission of the aggregated data signal at time T3. During the period from time T2 to time T3, bitmap information related to the success or failure of acquiring packets with SN#33 to #64 transmitted from STA1 is stored in the Link 2 scoreboard and updated sequentially.

[0260] On the other hand, STA2 acquires the transmission rights of Link 2 at time T4. That is, at time T4, the sender on Link 2 changes from STA1 to STA2. STA2 begins transmitting the data signal obtained by aggregating packets with SN#1 to #32, and completes the transmission of the aggregated data signal at time T6. After time T4, bitmap information related to the success or failure of acquiring packets with SN#1 to #32 transmitted from STA2 is stored in the Link 2 scoreboard and updated sequentially.

[0261] Additionally, STA2 acquires the transmission rights for Link 1 at time T7. That is, at time T7, the sender on Link 1 changes from STA1 to STA2. STA2 begins transmitting data signals obtained by aggregating packets with the same TID as Link 2 and SN#33 to #64, and completes the transmission of the aggregated data signals at time T8. After time T7, bitmap information related to the success or failure of acquiring packets with SN#33 to #64 transmitted from STA2 is stored in the Link 1 scoreboard and updated sequentially.

[0262] AP's MLD entities update the common scoreboard according to the above update rules.

[0263] Therefore, when the AP receives data signals from STA1 on both Link 1 and Link 2, and at time T2 when both the Link 1 scoreboard and the Link 1 scoreboard manage the bitmap information of STA1 with the same sender and the same TID, the AP updates the common scoreboard and stores the bitmap information related to whether the packet from STA1 was successfully acquired.

[0264] Then, even after time T4 when the sender on link 2 changes from STA1 to STA2, the success or failure information of packet acquisition from STA1 is stored in the common scoreboard and the link 1 scoreboard. Therefore, during the period from time T2 to T5, bitmap information related to the success or failure of packet acquisition from STA1 is continuously updated in the common scoreboard. As a result, at time T5 when STA1 finishes data transmission on link 1, bitmap information related to the success or failure of acquisition of packets with SN#1 to #64 transmitted from STA1 on link 1 and link 2 (i.e., the sender who has completed transmission and the success or failure information of TID acquisition) is stored in the common scoreboard. Therefore, the AP can... Figure 12 The block acknowledgment transmission process shown transmits common block acknowledgments to STA1 on link 1.

[0265] On the other hand, at time T7, the AP receives a data signal from STA2 on link 1, and both the link 1 scoreboard and the link 1 scoreboard manage the bitmap information of STA2, which has the same sender and the same TID. Therefore, a handover is performed in a manner that stores the bitmap information related to the success or failure of packet acquisition from STA2 in the common scoreboard. During the period from time T7 to time T8, the bitmap information related to the success or failure of packet acquisition from STA2 is continuously updated in the common scoreboard. At this time, depending on the storage capacity of the common scoreboard, the bitmap information related to STA1 stored so far is deleted. As in this embodiment, assuming the common scoreboard is a partial-state cache memory capable of storing packet acquisition success or failure information in a block acknowledgment session, the bitmap information related to STA1 is deleted by overwriting.

[0266] Subsequently, at time T8, when the data transmission by STA2 on link 2 ends, bitmap information related to the success or failure of acquiring packets with SN#1 to #64 transmitted from STA2 on links 1 and 2 (i.e., information on the successful acquisition of the sender and TID) is stored in the common scoreboard. Therefore, the AP can proceed according to... Figure 12 The block acknowledgment transmission process shown transmits common block acknowledgments to STA2 on link 2.

[0267] like Figure 21 As shown, STA1 first starts data transmission on link 1, and then starts data transmission with the same TID on link 2. However, if the data transmission on link 2 ends earlier than on link 1, that is, even if the data transmission start time and data transmission end time are reversed between links, the AP can still generate a common block acknowledgment and transmit it to STA1 by updating the common scoreboard according to the update rules of this disclosure. Furthermore, in STA2, the transmission time of data with the same TID on link 1 does not overlap with the transmission time of data with the same TID on link 2, but the AP can still generate a common block acknowledgment and transmit it to STA2 by updating the common scoreboard according to the update rules of this disclosure.

[0268] Figure 23 The illustration shows that in Figure 1 This is yet another example of a communication sequence of multi-link operations performed in the communication system shown. Furthermore, Figure 24 The diagram illustrates the execution Figure 23 The communication sequence shown illustrates the state of each scoreboard in the AP at each time point.

[0269] When STA1 acquires the transmission right of Link 1 at time T1, it begins transmitting the data signal obtained by aggregating packets with SN#1 to #32, and completes the transmission of the aggregated data signal at time T3. During the period from time T1 to time T3, bitmap information related to the success or failure of acquiring packets with SN#1 to #32 transmitted from STA1 is stored in the Link 1 scoreboard and updated sequentially.

[0270] When STA2 acquires the transmission right of Link 2 at time T2, it begins transmitting the data signal obtained by aggregating packets with SN#1 to #32, and completes the transmission of the aggregated data signal at time T4. During the period from time T2 to time T4, bitmap information related to the success or failure of acquiring packets with SN#1 to #32 transmitted from STA2 is stored in the Link 2 scoreboard and updated sequentially.

[0271] Additionally, STA2 acquires the transmission rights for Link 1 at time T5. That is, at time T5, the sender on Link 1 changes from STA1 to STA2. STA2 begins transmitting the data signal obtained by aggregating packets with the same TID as Link 2 and SN#33 to #64, and completes the transmission of the aggregated data signal at time T7. After time T5, bitmap information related to the success or failure of acquiring packets with SN#33 to #64 transmitted from STA2 is stored in the Link 1 scoreboard and updated sequentially.

[0272] On the other hand, STA1 acquires the transmission rights of Link 2 at time T6. That is, at time T6, the sender on Link 2 changes from STA2 to STA1. STA1 begins transmitting the data signal obtained by aggregating packets with the same TID as Link 1 and SN#33 to #64, and completes the transmission of the aggregated data signal at time T8. After time T6, bitmap information related to the success or failure of acquiring packets with SN#33 to #64 transmitted from STA1 is stored in the Link 2 scoreboard and updated sequentially.

[0273] The AP's MLD entity updates the common scoreboard according to the update rules described above. Therefore, at time T5, when both the Link 1 scoreboard and the Link 2 scoreboard manage the bitmap information of STA2 with the same sender and the same TID, the AP updates the common scoreboard and stores the bitmap information related to whether the packet from STA2 was successfully acquired.

[0274] Then, at time T6, when the sender on link 2 changes from STA2 to STA1, the information stored in the common scoreboard is bitmap information related to the success or failure of packet acquisition from STA2. Therefore, at time T7, when STA2 finishes data transmission on link 1, bitmap information related to the success or failure of acquiring packets with SN#1 to #64 transmitted from STA2 on both link 1 and link 2 (i.e., information on the successful or failed acquisition of the sender and TID) is stored in the common scoreboard. Therefore, the AP can... Figure 12 The block acknowledgment transmission process shown transmits common block acknowledgments to STA2 on link 1.

[0275] On the other hand, at time T6, the AP receives a data signal from STA1 on link 1. The link 1 scoreboard manages the bitmap information of STA1, while the link 2 scoreboard manages the bitmap information of STA2. Since the senders are different, the common scoreboard is not updated. Therefore, at time T8, when the data transmission of STA1 on link 1 ends, the bitmap information related to the success or failure of the acquisition of packets with SN#1 to #64 transmitted from STA2 on links 1 and 2 (i.e., acquisition success or failure information with different senders and different TIDs at the time of transmission completion) remains stored in the common scoreboard. As a result, the AP cannot update the data according to the data transmission schedule. Figure 12 The block acknowledgment transmission process shown generates a common block acknowledgment and transmits a normal block acknowledgment to STA1 on link 2.

[0276] exist Figure 23 and 24 In the example shown, STA1 and STA2 both transmit data to the AP using Link 1 and Link 2, respectively, with STA1 starting data transmission first and STA2 ending data transmission first. That is, the start and end times of data transmission between STA1 and STA2 are reversed. In this case, because the success or failure information for the entire block acknowledgment session of STA1, which ends data transmission later, is not stored in the common scoreboard, the AP cannot generate a common block acknowledgment and transmit it to STA1.

[0277] F. Second Example

[0278] In the first example, a method for generating common block confirmations based on a partial-state common scoreboard has been described. However, as referenced... Figure 23 and 24 As described, there are situations where common block acknowledgments cannot be generated and transmitted to some senders (STAs). Figure 23 and 24In the example shown, STA1 and STA2 both transmit data to the AP using Link 1 and Link 2, but the start time and end time of data transmission between STA1 and STA2 are reversed, and therefore the AP cannot generate and transmit a common block acknowledgment for STA1, whose data transmission end time is later.

[0279] In a partially-state common scoreboard, it is also possible to store bitmap information with multiple senders or multiple TIDs simultaneously, depending on the installed memory. Therefore, as a second example, a method for updating the scoreboard of each link based on the bitmap information of the common scoreboard will be described below, under the condition that the partially-state common scoreboard can store bitmap information with multiple senders or multiple TIDs simultaneously.

[0280] Figure 25 The flowchart illustrates the processing steps when the AP receives data during the data transmission phase.

[0281] The AP receives a data signal on a certain link (e.g., link 1) and updates the link scoreboard of the link MAC entity corresponding to that link using conventional methods based on whether the data acquisition was successful or not (step S2501).

[0282] Next, the AP checks whether a common block acknowledgment has been transmitted (step S2502). Specifically, the AP checks whether a block acknowledgment setting, including a common block acknowledgment, has been completed with the STA, which is the data sender (initiator), and whether the acknowledgment policy in the "MAC header / QoS control" field of the received packet is "common BA".

[0283] If the block acknowledgment setup with the data sender has not been completed or the acknowledgment policy in the "MAC header / QoS control" field of the received packet is not "common BA" ("No" in step S2502), the AP ends this process without updating the common scoreboard.

[0284] On the other hand, if the block acknowledgment setup has been completed with the data sender and the acknowledgment policy in the "MAC header / QoS control" field of the received packet is "common BA" ("Yes" in step S2502), the AP determines whether to update the scoreboard.

[0285] As a determination of whether to update the scoreboard, the AP first checks whether the link scoreboard and the common scoreboard of the link that has received data manage bitmaps with the same sender and the same TID (step S2503).

[0286] If the link scoreboard of a link that has already received data (e.g., link 1) and the common scoreboard manage bitmaps with the same sender and the same TID ("Yes" in step S2503), the AP updates the bitmap information of the link scoreboard of the link that has already received data based on the bitmap information of the common scoreboard (step S2505), and ends this process. As a result, in the link scoreboard of the link that has already received data (e.g., link 1), the success or failure information of data acquisition received with the same sender and the same TID is updated sequentially.

[0287] Alternatively, if the link scoreboard and the common scoreboard of a link that has received data do not manage bitmaps with the same sender and the same TID ("No" in step S2503), the AP further checks whether the storage capacity of the common scoreboard is sufficient (step S2504).

[0288] If the common scoreboard's storage capacity is insufficient (No in step S2504), the AP terminates the process without updating the common scoreboard.

[0289] On the other hand, if the storage capacity of the common scoring board is sufficient ("Yes" in step S2505), the AP updates the common scoring board based on the bitmap information of the link 1 scoring board (step S2506). As a result, as long as the storage capacity is sufficient, the common scoring board is updated with information on whether the data received with a new sender or a new TID was successfully acquired.

[0290] Figure 26 This is a diagram illustrating an example of the internal sequence when the AP receives data signals during the data transmission phase. Figure 26 The illustration shows an example of the internal sequence corresponding to step S2505 in the flowchart shown in 25 when updating the bitmap information of the common scoreboard based on the bitmap information of the Link 1 MAC scoreboard. The AP is an MLO-compatible communication device, i.e., an MLD, and includes a Link 1 MAC entity and a Link 2 MAC entity that perform individual data processing for each link, and an MLD entity that performs common data processing for all links, such as... Figure 3 As shown in the figure. In addition, as a scoreboard for storing information on whether data acquisition was successful or not in the AP, a Link 1 scoreboard and a Link 2 scoreboard are provided, respectively included in the Link 1 MAC entity and the Link 2 MAC entity, and a common scoreboard is included in the MLD entity.

[0291] When the Link 1 MAC entity updates the Link 1 scoreboard in response to receiving data on Link 1 (scoreboard update), the Link 1 MAC entity notifies the MLD entity of the scoreboard update information, including the initiator address, TID, and updated SN.

[0292] The MLD entity determines, based on information obtained from the Link 1 MAC entity, whether bitmap information with the same sender information (i.e., the same initiator address and the same TID) is managed by the common scoreboard (common scoreboard update determination). This determination process corresponds to step S2503 in the flowchart shown in 25. Here, it is assumed that block acknowledgment settings have been completed with the STA as the data sender (initiator), and the acknowledgment policy in the "MAC Header / QoS Control" field of the received packet specifies "common BA".

[0293] Then, when a bitmap with the same initiator address and TID as the Link 1 scoreboard is detected and managed by the common scoreboard, the MLD entity determines to update the Link 1 scoreboard. In this case, the MLD entity transmits scoreboard information, including bitmap information, WindowStart, WindowSize, initiator address, and TID, to the Link 1 MAC entity.

[0294] The Link 1 MAC entity updates the Link 1 scoreboard based on information included in the common scoreboard obtained from the MLD entity (scoreboard update). The Link 1 MAC entity updates the Link 1 scoreboard according to the following procedure.

[0295] (1) Set WindowEnd RL1 =max(WindowEnd) RL1 WindowEnd Rc That is, the Link 1 scoreboard is updated based on the larger of the final values ​​of the sequence numbers to be stored in the Link 1 scoreboard and the Link 2 scoreboard.

[0296] (2) Set WindowStart RL1 =WindowEnd RL1 -WindowSize RL1 +1.

[0297] (3) From WindowStart Rc To WindowEnd Rc In each SN, the SN indicating the Link 1 Scoreboard is set to "1" in the bitmap information of the common scoreboard.

[0298] Figure 27 The illustration shows another example of the internal sequence when the AP receives a data signal during the data transmission phase. Figure 27 The illustration shows an example of the internal sequence corresponding to step S2506 in the flowchart shown in 25 when updating the bitmap information of the link 1 scoreboard based on the bitmap information of the common MAC scoreboard.

[0299] When the Link 1 MAC entity updates the Link 1 scoreboard in response to receiving data on Link 1 (scoreboard update), the Link 1 MAC entity notifies the MLD entity of the scoreboard update information, including the initiator address, TID, and updated SN.

[0300] The MLD entity determines, based on information obtained from the Link 1 MAC entity, whether bitmap information with the same sender information (i.e., the same initiator address and the same TID) is managed by the common scoreboard (common scoreboard update decision).

[0301] Then, when it is determined that the common scoreboard and the Link 1 scoreboard do not manage bitmap information with the same initiator address and the same TID, and the common scoreboard has sufficient storage capacity, the MLD entity decides to update the common scoreboard. In this case, the MLD entity transmits a scoreboard request to the Link 1 MAC entity.

[0302] The Link 1 MAC entity responds to a scoreboard request from the MLD entity by transmitting scoreboard information including bitmap information, WindowStart, WindowEnd, initiator address, and TID.

[0303] Then, the MLD entity updates the common scoreboard based on the scoreboard information collected from the Link 1 MAC entity and the Link 2 MAC entity according to the following procedure (common scoreboard update).

[0304] (1) Set WindowEnd Rc =SN.

[0305] (2) Set WindowStart Rc =WindowEnd Rc -WindowSize Rc +1.

[0306] (3) Take WindowStart as the starting point Rc And the endpoint is WindowEnd Rc Create WindowSize by first entering 0. Rc Bitmap of dimensions.

[0307] (4) Set “1” in the part indicated by the SN of the bitmap information of the common scoreboard.

[0308] Figure 28 The flowchart illustrates the process of AP transport block acknowledgment.

[0309] When the reception of a data signal is completed on a certain link (e.g., link 1) (step S2801), the AP generates a block acknowledgment based on the information of the link scoreboard of the link (e.g., link 1) that has received the data signal, sends a transmission block acknowledgment to the STA as the sender (step S2802), and ends the process.

[0310] according to Figure 28 The processing procedure shown updates the success / failure information of packets from the same sender and the same TID sequentially in the link scoreboard of the link that has already received data. Therefore, in step S2802 above, the AP can generate and transmit a common block acknowledgment.

[0311] Figure 29 The illustration shows that in Figure 1 The example shown is a communication sequence of multi-link operations performed in a communication system. Figure 29 In the example of the communication sequence shown, such as Figure 23 As shown, TA1 and STA2 both use Link 1 and Link 2 to transmit data to the AP, and the data transmission start time and data transmission end time are reversed between STA1 and STA2.

[0312] Note that, Figure 29 The horizontal axis represents the time axis and indicates the communication operations of AP, STA1, and STA2 at each time on each link. Solid-lined rectangles represent transmitted frames corresponding to the communication device, link, and time; vertical solid-lined arrows indicate frame transmission to the destination; and dotted-lined rectangles represent received frames.

[0313] also, Figure 30 The diagram illustrates when execution Figure 29 The communication sequence shown is a symbol of the Link 1 MAC entity and the common scoreboard bitmap information for each link in the AP at each time. (By WindowStart) R The information matching the indicated SN is stored at the left end of the bitmap information for each scoreboard, and is controlled by WindowEnd. R Information matching the indicated SN is stored at the right end. At each bit position on the bitmap, the success or failure of packet acquisition with the corresponding SN is indicated by 0 and 1. The SN of packets that have not yet been received is indicated by "0". Furthermore, the SN of acquired packets is indicated by "X", and is stored as either 0 or 1 depending on whether the packet acquisition was successful or failed.

[0314] Generally, the TID value is also related to scoreboard management, but for simplicity, it is assumed here that only data with the same TID is transmitted. Furthermore, it is assumed that WindowSize = 64, and that packets with SN#1 to #32 are transmitted on link 1 in STA1 and STA2, while data with SN#33 to #64 are transmitted on link 2. However, the invention is not limited to the above assumptions, and for example, different numbers of packets may be included in link 1 and link 2, or the number of packets may be less than the WindowSize.

[0315] In the following text, reference will be made to Figure 30 The state of each scoreboard shown is used to describe Figure 29 The communication sequence shown in .

[0316] When STA1 acquires the transmission right of Link 1 at time T1, it begins transmitting the data signal obtained by aggregating packets with SN#1 to #32, and completes the transmission of the aggregated data signal at time T3. During the period from time T1 to time T3, bitmap information related to the success or failure of acquiring packets with SN#1 to #32 transmitted from STA1 is stored in the Link 1 scoreboard and updated sequentially.

[0317] During the time period from time T1 to time T3, the memory capacity of the common scoreboard is sufficient, so the bitmap information related to the success or failure of the acquisition of packets with SN#1 to #32 transmitted from STA1 on link 1 is stored in the common scoreboard and updated sequentially.

[0318] When STA2 acquires the transmission right of Link 2 at time T2, it begins transmitting the data signal obtained by aggregating packets with SN#1 to #32, and completes the transmission of the aggregated data signal at time T4. During the period from time T2 to time T4, bitmap information related to the success or failure of acquiring packets with SN#1 to #32 transmitted from STA2 is stored in the Link 2 scoreboard and updated sequentially.

[0319] During the time period from time T2 to time T4, the common scoreboard manages the bitmap information of STA1, which is a different sender from the link 2 scoreboard. However, the memory capacity is sufficient, so the bitmap information related to the success or failure of the acquisition of packets with SN#1 to #32 transmitted from STA2 on link 2 is also stored in the common scoreboard and is updated sequentially.

[0320] Additionally, STA2 acquires the transmission rights for Link 1 at time T5. That is, at time T5, the sender on Link 1 changes from STA1 to STA2. STA2 begins transmitting data signals obtained by aggregating packets with the same TID as Link 2 and SN#33 to #64, and completes the transmission of the aggregated data signals at time T7. After time T5, bitmap information related to the success or failure of acquiring packets with SN#33 to #64 transmitted from STA2 is stored in the Link 1 scoreboard and updated sequentially.

[0321] During the period from time T5 to time T7, the common scoreboard manages the bitmap information of STA2, the same sender as the link 1 scoreboard. Therefore, the bitmap information of the link 1 scoreboard is updated based on the common scoreboard. Thus, at time T7, when STA2's data transmission on link 1 ends, bitmap information related to the success or failure of acquiring packets with SN#1 to #64 transmitted from STA2 on both link 1 and link 2 (i.e., information on the sender who completed transmission and the success or failure of acquiring the TID) is stored in the link 1 scoreboard. As a result, according to... Figure 28 The block acknowledgment transmission process shown in the diagram allows the AP to transmit a common block acknowledgment to STA2 on Link 1 based on the bitmap information stored in the Link 1 scoreboard.

[0322] Additionally, STA1 acquires the transmission rights for Link 2 at time T6. That is, at time T6, the sender on Link 2 changes from STA2 to STA1. STA1 begins transmitting data signals obtained by aggregating packets with the same TID as Link 1 and SN#33 to #64, and completes the transmission of the aggregated data signals at time T8. After time T6, bitmap information related to the success or failure of acquiring packets with SN#33 to #64 transmitted from STA1 is stored in the Link 1 scoreboard and updated sequentially.

[0323] At this time, the common scoring board manages the bitmap information of STA1, the same sender as the link 2 scoring board, and therefore the bitmap information of the link 2 scoring board is updated based on the common scoring board. As a result, at time T8 when STA2 finishes data transmission on link 1, bitmap information related to the success or failure of acquiring packets with SN#1 to #64 transmitted from STA1 on both link 1 and link 2 (i.e., information on the successful or unsuccessful acquisition of the sender and TID) is stored in the link 2 scoring board. Therefore, according to Figure 28 The block acknowledgment transmission process shown in the diagram allows the AP to transmit common block acknowledgments to STA1 on Link 2 based on bitmap information stored in the Link 2 scoreboard.

[0324] G. Effect

[0325] This section will summarize the effects achieved through this disclosure.

[0326] (1) The MLO-compatible communication device disclosed herein includes a link scoreboard that manages success or failure information of received packets for each link and a common scoreboard that manages success or failure information of received packets across multiple links. Although the common scoreboard is managed as a cache type, the common block acknowledgments of success or failure information of received packets across multiple links can be transmitted with high reliability, and the common scoreboard can be installed in inexpensive memory.

[0327] (2) Information regarding the ability of the communication device using this disclosure to exchange indications with another communication device regarding the possibility of using a common scoreboard to manage the success or failure of packet acquisition on multiple links. Therefore, the data sender can correctly set the acknowledgment strategy by determining whether a common block acknowledgment can be generated on the receiving side.

[0328] (3) According to this disclosure, the data sender adds and transmits information about whether to update the common scoreboard in response to a block acknowledgment request. Therefore, the receiving side can update the common scoreboard simultaneously with the link scoreboard.

[0329] (4) The MLO-compatible communication device of this disclosure updates the link scoreboard based on the information of the common scoreboard. Therefore, even when multiple data senders use multiple links to transmit data alternately, it is possible to generate and transmit common block acknowledgments.

[0330] Industrial applicability

[0331] The present disclosure has been described in detail above with reference to specific embodiments. However, it is obvious that those skilled in the art can make modifications and substitutions to the embodiments without departing from the spirit of the present disclosure.

[0332] For example, by applying this disclosure to a wireless LAN system according to the IEEE 802.11 standard, similar effects can naturally be obtained, even by applying this disclosure to a wireless system performing multi-link communication according to another communication standard.

[0333] In short, this disclosure has been described by way of example, and the content described herein should not be construed as limiting. The claims should be considered in order to determine the gist of this disclosure.

[0334] Note that this disclosure may have the following configurations.

[0335] (1) A communication device that performs wireless communication using multiple links, the communication device comprising:

[0336] A common data processing unit includes a shared storage unit of a cache type that stores the success or failure of packet acquisition received on the multiple links, and performs common data processing on packets received on each link; and

[0337] The control unit controls the transmission of response signals to received packets, wherein...

[0338] The control unit generates a common response signal that includes the acquisition success or failure information received on the multiple links, based on the acquisition success or failure information held in the common storage unit.

[0339] (2) The communication device according to (1) further includes:

[0340] The individual data processing unit includes an individual storage unit that stores information on whether packets received on the individual link were successfully acquired, and performs individual data processing on the packets received on the individual link.

[0341] (3) The communication device according to (2), wherein

[0342] The control unit performs update processing of the common storage unit based on whether the acquisition was successful or not, related to the same sender information stored in the common storage unit and the individual storage units.

[0343] (4) The communication device according to (3), wherein

[0344] When individual storage units store the same sender information related to successful or unsuccessful retrieval as shared storage units, the control unit performs update processing on shared storage units based on the same sender information related to successful or unsuccessful retrieval stored in individual storage units.

[0345] (5) The communication device according to (3) or (4), wherein

[0346] When an individual storage unit does not store the same sender information related to the success or failure of acquisition as the common storage unit, but instead the individual storage units on multiple links store the same sender information related to the success or failure of acquisition, the control unit performs the update processing of the common storage unit based on the same sender information related to the success or failure of acquisition stored in the individual storage units on the multiple links.

[0347] (6) The communication device according to (5), wherein

[0348] The control unit performs the update process of the common storage unit based on the largest final value of the sequence number stored in the individual storage units on the multiple links.

[0349] (7) The communication device according to (5) or (6), wherein

[0350] For at least one of the individual storage units on the multiple links that indicates a successfully acquired sequence number, the control unit also sets a value indicating successful acquisition in the acquisition success or failure information of the common storage unit.

[0351] (8) The communication device according to any one of (1) to (7), wherein

[0352] The control unit performs control by exchanging information with the packet sender indicating whether it can manage the shared storage unit.

[0353] (9) The communication device according to (8), wherein

[0354] If the control unit detects that it can manage the shared storage unit with the sender and requests the transmission of a shared response signal with the header of the received data signal, the control unit attempts to update the shared storage unit.

[0355] (10) The communication device according to any one of (1) to (9), wherein

[0356] The control unit determines whether to generate a common signal based on the sender information managed by the common storage unit.

[0357] (11) The communication device according to (10), wherein

[0358] When the shared storage unit stores acquisition success or failure information related to the sender information of the received packet, the control unit generates a shared response signal based on the acquisition success or failure information stored in the shared storage unit. When the shared storage unit does not store acquisition success or failure information related to the sender information of the received packet, the control unit generates an individual response signal based on the acquisition success or failure information stored in the individual storage unit of the link that has received the packet.

[0359] (12) The communication device according to any one of (1) to (11), wherein

[0360] The control unit determines whether to update the common storage unit based on the information included in the response request signal received from the sender.

[0361] (13) The communication device according to (2), wherein

[0362] The control unit performs update processing for the individual storage units based on whether the acquisition was successful or not, related to the same sender information stored in the common storage unit and the individual storage units.

[0363] (14) A communication method for performing wireless communication using multiple links, the communication method comprising:

[0364] The common data processing step involves using a shared storage unit—a cache-type unit storing the success or failure of packet acquisition received on each of the multiple links—to perform common data processing on the packets received on each link; and

[0365] The control steps control the transmission of response signals to received packets, wherein...

[0366] In the control step, based on the acquisition success or failure information held in the common storage unit, a common response signal is generated that includes the acquisition success or failure information received on the multiple links.

[0367] (15) A communication device, comprising:

[0368] Communication unit, using multiple links to perform wireless communication; and

[0369] The control unit controls the wireless communication operation in the communication unit, wherein...

[0370] When data signals are transmitted on the multiple links, the control unit provides notification of whether there is a request for a common response signal, which includes information on whether the reception of data signals on the multiple links was successful or not.

[0371] (16) The communication device according to (15), wherein

[0372] The control unit performs control to transmit a response request signal for the transmission of a common response signal.

[0373] (17) The communication device according to (16), wherein

[0374] The control unit performs control to transmit a response request signal in order to initialize a shared storage unit that stores information related to the success or failure of data signal reception on the multiple links.

[0375] (18) A communication method for performing wireless communication using multiple links, the communication method comprising:

[0376] The steps include providing notification of whether a request for a common response signal has been received and transmitting data signals, the common response signal including information regarding the success or failure of acquisition related to the reception of data signals on the multiple links; and

[0377] The steps for receiving a response signal.

[0378] List of reference numerals

[0379] 200 communication devices

[0380] 210 Communication Unit

[0381] 211 Communication Control Unit

[0382] 212 Communication Storage Unit

[0383] 213 Common Data Processing Unit

[0384] 214 Individual Data Processing Units

[0385] 215 Signal Processing Unit

[0386] 216 Wireless Interface Unit

[0387] 217 Amplification Units

[0388] 220 Control Unit

[0389] 230 storage units

[0390] 240 antenna

Claims

1. A communication device that performs wireless communication using multiple links, the communication device comprising: Communication unit; as well as Control unit: Controls the reception of ADD Block Acknowledgment (ADDBA) request frames from a specific sender among multiple senders. The ADDBA request frame sets a block acknowledgment policy for sender information related to the specific sender and the service identifier (TID). Control the sending of ADDBA response frames to the specific sender; Set a block confirmation strategy for the sender information; Controlling the reception of packets from the specific sender on each of the multiple links; The success or failure information of packet acquisition received on each of the multiple links is stored in a link-specific individual storage unit; For packets received from the specific sender on each of the multiple links, the corresponding success or failure information is retrieved from the individual storage unit; The corresponding success or failure information is stored in a common storage unit of a partial state cache type; Generate a block confirmation signal that includes the corresponding acquisition success or failure information stored in a shared storage unit of a partial state cache type; as well as Control the transmission of the block acknowledgment signal on one of the multiple links.

2. The communication device according to claim 1, wherein The control unit performs update processing of the common storage unit based on whether the acquisition was successful or not, related to the same sender information stored in the common storage unit and the individual storage units.

3. The communication device according to claim 2, wherein When individual storage units store the same sender information related to successful or unsuccessful retrieval as shared storage units, the control unit performs update processing on shared storage units based on the same sender information related to successful or unsuccessful retrieval stored in individual storage units.

4. The communication device according to claim 2, wherein When an individual storage unit does not store the same sender information related to the success or failure of acquisition as the common storage unit, but instead the individual storage units on multiple links store the same sender information related to the success or failure of acquisition, the control unit performs the update processing of the common storage unit based on the same sender information related to the success or failure of acquisition stored in the individual storage units on the multiple links.

5. The communication device according to claim 4, wherein The control unit performs the update process of the common storage unit based on the largest final value of the sequence number stored in the individual storage units on the multiple links.

6. The communication device according to claim 4, wherein For at least one of the individual storage units on the multiple links that indicates a successfully acquired sequence number, the control unit also sets a value indicating successful acquisition in the acquisition success or failure information of the common storage unit.

7. The communication device according to claim 1, wherein The control unit performs control by exchanging information with the packet sender indicating whether it can manage the shared storage unit.

8. The communication device according to claim 7, wherein If the control unit detects that it can manage the shared storage unit with the sender and requests the transmission of a shared response signal with the header of the received data signal, the control unit attempts to update the shared storage unit.

9. The communication device according to claim 1, wherein The control unit determines whether to generate a common signal based on the sender information managed by the common storage unit.

10. The communication device according to claim 9, wherein When the shared storage unit stores acquisition success or failure information related to the sender information of the received packet, the control unit generates a shared response signal based on the acquisition success or failure information stored in the shared storage unit. When the shared storage unit does not store acquisition success or failure information related to the sender information of the received packet, the control unit generates an individual response signal based on the acquisition success or failure information stored in the individual storage unit of the link that has received the packet.

11. The communication device according to claim 1, wherein The control unit determines whether to update the common storage unit based on the information included in the response request signal received from the sender.

12. The communication device according to claim 1, wherein The control unit performs update processing for the individual storage units based on whether the acquisition was successful or not, related to the same sender information stored in the common storage unit and the individual storage units.

13. A communication method for performing wireless communication using multiple links, the communication method comprising: Controls the reception of ADD Block Acknowledgment (ADDBA) request frames from a specific sender among multiple senders. The ADDBA request frame sets a block acknowledgment policy for sender information related to the specific sender and the service identifier (TID). Control the sending of ADDBA response frames to the specific sender; Set a block confirmation strategy for the sender information; Controlling the reception of packets from the specific sender on each of the multiple links; The success or failure information of packet acquisition received on each of the multiple links is stored in a link-specific individual storage unit; For packets received from the specific sender on each of the multiple links, the corresponding success or failure information is retrieved from the individual storage unit; The corresponding success or failure information is stored in a common storage unit of a partial state cache type; Generate a block confirmation signal that includes the corresponding acquisition success or failure information stored in a shared storage unit of a partial state cache type; as well as Control the transmission of the block acknowledgment signal on one of the multiple links.

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