Method for wireless data transmission in wireless network

Abstract

The present invention provides a method for wireless data transmission in a wireless network. The implementation of the embodiments of the present invention can improve the performance of the wireless network. Among them, the present invention provides a method for wireless data transmission in a wireless network, comprising: transmitting a first physical layer protocol data unit (PPDU) on a first wireless link during a first transmission opportunity (TXOP), and transmitting a second PPDU on a second wireless link during a second TXOP; detecting a transmission failure on the first wireless link; and terminating the second TXOP in response to detecting the transmission failure on the first wireless link.

Description

Technical Field

[0001] Embodiments of the present invention generally relate to the field of wireless communications. More specifically, embodiments of the present invention relate to systems and methods for enhanced multi-link operations in wireless networks. Background Art

[0002] Unless otherwise indicated herein, the approaches described in this section are not prior art to the claims listed below and are not admitted to be prior art by inclusion in this section.

[0003] Modern electronic devices often use Wi-Fi to wirelessly send and receive data with other electronic devices, and many of these electronic devices are "dual band" devices, which include at least two wireless transceivers capable of operating in different frequency bands (e.g., 2.4 GHz, 5 GHz, and 6 GHz). In most cases, a wireless device can only communicate over one frequency band at a time. For example, older low-power devices (such as battery-powered devices) typically operate on the 2.4 GHz band. Newer devices and devices that require greater bandwidth typically operate on the 5 GHz band. The availability of the 6 GHz band is a recent advancement that can provide higher performance, lower latency, and faster data rates.

[0004] Using a single frequency band may not meet the bandwidth or latency requirements of some devices. Therefore, some developing wireless communication methods increase communication bandwidth by operating on multiple frequency bands simultaneously (technically referred to as link aggregation or multi-link operation). Advantageously, multi-link operation can provide higher network throughput and improved network flexibility compared to traditional technologies for wireless communication.

[0005] Due to transmission power leakage between links, some Multi-Link Devices (MLDs) supporting multi-link operation are susceptible to In-Device Coexistence (IDC) interference when two or more links of the MLD are adjacent to each other. Due to IDC interference, some MLDs cannot support simultaneous transmission and reception using multiple links (called Non-Simultaneous Transmit and Receive (NSTR) link sets). Therefore, multiple links of some MLDs only support secondary wireless links when using the primary wireless link on the NSTR link set. In the event of a primary link transmission failure, the use of the secondary link may degrade the performance of the wireless network when the primary link is used to recover from the transmission failure.

[0006] A method for multi-link operation is needed. Summary of the invention

[0007] The invention provides a method for wireless data transmission in a wireless network.

[0008] The present invention provides a method for wireless data transmission in a wireless network, comprising: transmitting a first physical layer protocol data unit (PPDU) on a first wireless link during a first transmission opportunity (TXOP), and transmitting a second PPDU on a second wireless link during a second TXOP; detecting a transmission failure on the first wireless link; and terminating the second TXOP in response to detecting the transmission failure on the first wireless link.

[0009] The present invention provides another method for wireless data transmission in a wireless network, comprising: transmitting a first non-initial physical layer protocol data unit (PPDU) on a first wireless link and transmitting a second non-initial PPDU on a second wireless link; determining that transmitting the first non-initial PPDU on the first wireless link includes a transmission failure; receiving a confirmation in response to transmitting the second non-initial PPDU on the second wireless link; transmitting a third non-initial PPDU on the second wireless link after receiving the confirmation; and transmitting a fourth non-initial PPDU on the first wireless link at substantially the same time as transmitting the third non-initial PPDU.

[0010] Another method for performing wireless data transmission in a wireless network provided by the present invention includes: transmitting a first physical layer protocol data unit (PPDU) on a first wireless link during a first transmission opportunity (TXOP), and transmitting a second PPDU on a second wireless link during a second TXOP; determining that the transmission of the second PPDU on the second wireless link includes a transmission error; receiving an acknowledgment in response to the transmission of the first PPDU on the first wireless link during the first TXOP; and transmitting a third PPDU on the first wireless link during the first TXOP and after determining that the transmission of the second PPDU on the second wireless link includes a transmission error; wherein the first wireless link is a main link of a multi-link device, and the second wireless link is an auxiliary link of the multi-link device.

[0011] The implementation of the embodiments of the present invention can improve the performance of a wireless network. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 An exemplary synchronized uplink (UL) transmission 100 between an NSTR APMLD 105 and an NSTR non-AP MLD 110 performed using contention-based channel access on a primary link and a secondary link is depicted.

[0013] Figure 2An exemplary synchronous transmission 200 of a downlink (DL) link TXOP is depicted.

[0014] Figure 3 An exemplary wireless transmission 300 is depicted for a downlink TXOP for synchronous transmissions when the primary link is busy.

[0015] Figure 4a Depicted is an exemplary synchronous transmission 400 of a downlink TXOP initiated by an NSTR AP MLD 405 in accordance with an embodiment of the present invention.

[0016] Figure 4b Depicted is an exemplary synchronous transmission of a downlink TXOP initiated by the NSTR AP MLD 405b in accordance with an embodiment of the present invention.

[0017] Figure 5 Depicted is an exemplary synchronous transmission 500 of a downlink TXOP initiated by an NSTR AP MLD in accordance with an embodiment of the present invention.

[0018] Figure 6 An exemplary synchronization transmission 600 initiated by an NSTR AP MLD 605 to resume an existing TXOP on a primary link and terminate a TXOP on a secondary link is shown in accordance with an embodiment of the present invention.

[0019] Figure 7 Depicted is an exemplary synchronous transmission 700 of a downlink TXOP initiated by an NSTR AP MLD in accordance with an embodiment of the present invention.

[0020] Figure 8 Depicted is an exemplary synchronous transmission 800 of a downlink TXOP initiated by an NSTR AP MLD 805 in accordance with an embodiment of the present invention.

[0021] Fig. 9 Depicted is an exemplary synchronous transmission 900 of a downlink TXOP initiated by an NSTR AP MLD 905 in accordance with an embodiment of the present invention.

[0022] Fig.10 Depicted is an exemplary synchronous transmission of a downlink TXOP initiated by the NSTR AP MLD 1005 in accordance with an embodiment of the present invention.

[0023] Fig.11 Depicted is an exemplary synchronous transmission 1100 of a downlink TXOP initiated by an NSTR AP MLD in accordance with an embodiment of the present invention.

[0024] Fig.12is a flow chart depicting exemplary steps of a computer-implemented process 1200 for transmitting data in a wireless network over multiple links of an NSTR MLD in accordance with an embodiment of the present invention.

[0025] Fig.13 is a flow chart depicting exemplary steps of a computer-implemented process 1300 for transmitting data in a wireless network over multiple links of an NSTR MLD in accordance with an embodiment of the present invention.

[0026] Fig.14 is a flow chart depicting exemplary steps of a computer-implemented process 1400 for transmitting data in a wireless network over multiple links of an NSTR MLD in accordance with an embodiment of the present invention.

[0027] Fig.15 An exemplary wireless device 1500 is depicted upon which embodiments of the present invention may be implemented. DETAILED DESCRIPTION

[0028] Reference will now be made in detail to several embodiments. Although the claimed subject matter will be described in conjunction with alternative embodiments, it should be understood that it is not intended to limit the claimed subject matter to these embodiments. On the contrary, the claimed subject matter is intended to cover substitutions, modifications, and equivalents, which are also included in the spirit and scope of the claimed subject matter defined by the appended claims.

[0029] Furthermore, in the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the claimed subject matter. However, one of ordinary skill in the art will recognize that embodiments of the present invention may be practiced without these specific details or their equivalents. Furthermore, the present invention does not describe in detail well-known methods, processes, components, and circuits in order to avoid unnecessarily obscuring the aspects and features of the subject matter of the present invention.

[0030] Some portions of the following detailed description are presented and discussed in terms of methods. Although in the diagrams (e.g., Figure 12-14 ) discloses steps and their order, but these steps and order are exemplary only. Embodiments of the present invention are also suitable for performing various other steps or variations of the steps listed in the flowcharts of the accompanying drawings herein, and can be performed in a different order than described herein.

[0031] Some parts of the following detailed description are presented in terms of symbolic representations of processes, steps, logic blocks, operations, and other operations on data bits that can be performed on a computer memory. These descriptions and representations are means used by those skilled in the art of data processing to most effectively communicate the content of their work to other technicians in the field. The processes described herein, the steps, logic blocks, operations, etc. performed by a computer are generally considered to be a self-consistent sequence of steps or instructions that lead to a desired result. These steps are steps that require physical operations on physical quantities. Typically, although not necessarily, these quantities take the form of electrical or magnetic signals that can be stored, transmitted, combined, compared, and otherwise operated on a computer system. It has proven to be convenient to refer to these signals as bits, values, elements, symbols, characters, terms, numbers, etc. for common reasons.

[0032] It should be remembered, however, that all of these and similar terms are to be associated with the appropriate physical quantities and that these terms are merely convenient labels applied to these quantities. Unless otherwise clearly indicated from the following discussion, it should be understood that throughout, discussions using terms such as "access," "configure," "coordinate," "store," "transmit," "authenticate," "identify," "request," "report," "determine," etc., refer to the actions and processes of a computer system or similar electronic computing device to manipulate and transform data represented as physical (electronic) quantities in the computer system's registers and memories into other data represented as physical quantities in the computer system's memories or registers or other such information storage, transmission, or display devices.

[0033] Some embodiments may be described in the context of computer-executable instructions (e.g., program modules) executed by one or more computers or other devices. Typically, program modules include routines, programs, objects, components, data structures, etc. that perform specific tasks or implement specific abstract data types. Typically, the functionality of program modules can be combined or distributed as desired in various embodiments.

[0034] Enhanced multi-link operation

[0035] Embodiments of the present invention provide improved multi-link operation when recovering from a transmission failure on a radio link of an NSTR link pair. During synchronous transmission on the NSTR link pair, a transmission failure of a MAC Service Data Unit (MPDU) may occur on either link of the NSTR link pair. When an AP MLD operates on the NSTR link pair, error recovery may be performed. According to some embodiments, when a transmission failure is detected on one of the radio links, error recovery may be performed and the timing of synchronous transmission on another radio link may be managed to advantageously avoid IDC interference and improve the performance of the wireless network.

[0036] When the AP MLD operates on the NSTR link pair, the synchronous transmission between the NSTR APMLD and the STR / NSTR non-AP MLD can avoid IDC interference by performing contention-based channel access on the NSTR link pair and starting synchronous transmission when the constraint conditions are met. A primary link is designated for the NSTR link pair, and the other link is called the secondary link (or non-primary link) of the NSTR link pair. According to some embodiments, the secondary link can initiate PPDU transmission only when the stations (STAs) in the primary link attached to the same MLD initiate PPDU as the TXOP holder at substantially the same start time.

[0037] Figure 1 An exemplary synchronous uplink transmission 100 between an NSTR APMLD 105 and an NSTR non-AP MLD 110 is depicted, performed using contention-based channel access on both the primary and secondary links. When the TXOP initiator obtains medium access on both links, the transmissions begin simultaneously. Figure 1 In the example of FIG. 1 , STA1 (station 1) 115 and STA2 (station 2) 120 are attached to the same non-STR non-AP MLD 110 (TXOP initiator). AP1 (access point 1) 125 and AP2 (access point 2) 130 are attached to the same non-STR AP MLD 105 (TXOP responder). STA1 115 and STA2 120 initiate Enhanced Distributed Channel Access (EDCA) backoff (e.g., random backoff) 135 and 140 on the primary link and the secondary link, respectively.

[0038] When the Random Backoff (RBO) 135 of STA1 115 counts down to zero on the primary link first, it can wait for the RBO 140 of STA 2 120 to count down to zero on the auxiliary link. Once the RBO 140 of STA 2 120 counts down to zero, if the primary link is idle based on the virtual CS and the physical CS, STA1 115 and STA2 120 can transmit PPDUs 145 and 150 at the same time. The ends of the PPDUs 145 and 150 on the primary link and the auxiliary link are aligned to avoid IDC interference. In addition, the start of the PPDU 145 on the waiting link (e.g., the primary link) is aligned with the start of the PPDU 150 on the other link (e.g., the auxiliary link).

[0039] Figure 2An exemplary synchronous transmission 200 of a downlink TXOP is depicted. AP1 225 and AP2 230 are attached to the same non-STR AP MLD 205 (TXOP initiator). STA1 215 and STA2 220 are attached to the same non-STR non-AP MLD 210 (TXOP responder). AP1 225 and AP2 230 perform EDCA backoff on the primary link and the secondary link, respectively. When the RBO of AP1 225 counts down to zero on the primary link first, it can wait for the RBO 240 of AP2 230 to count down to zero on the secondary link. Once the RBO 240 of AP2 230 counts down to zero, if the primary link is idle based on virtual CS and physical CS, AP1 225 and AP2 230 can transmit PPDUs simultaneously. The end of PPDUs 245 and 250 on the primary link and the secondary link are aligned. Transmission PPDU 245 on the waiting link (eg, primary link) begins substantially simultaneously with transmission of PPDU 250 on another link (eg, auxiliary link).

[0040] Figure 3 An exemplary wireless transmission 300 for downlink TXOP for synchronous transmission when the primary link is busy is depicted. AP1 325 and AP2 330 are attached to the same non-STR AP MLD 305 (TXOP initiator). STA1 315 and STA2 320 are attached to the same non-STR non-AP MLD 310 (TXOP responder). AP1 325 and AP2 330 perform EDCA backoff 335 and 340 on the primary link and the secondary link, respectively. If the RBO 340 of AP2 330 counts down to zero first, it can wait for the RBO 335 of AP1 325 to count down to zero, or the backoff can be suspended when the channel becomes busy (e.g., Overlapping Basic Service Set (OBSS) is busy, other systems are transmitting). When the primary link is busy, AP2 330 does not transmit on the secondary link.

[0041] Implementing enhanced error recovery for multilink operations with multilink devices

[0042] A transmission failure of an MPDU transmitted during multi-link operation may occur after an MPDU that requires an immediate response is transmitted. In this case, the STA waits for a timeout interval of duration aSIFSTime+aSlotTime+aRxPHYStartDelay, the timeout interval being started by the MAC receiving a primitive (e.g., a "PHY-TXEND.confirm" primitive) from the PHY layer. If the "PHY-RXSTART.indication" primitive is not received during the timeout interval, the transmission of the MPDU is considered to have failed. If the "PHY-RXSTART.indication" primitive is received during the timeout interval, the STA waits for the corresponding "PHY-RXEND.indication" primitive to identify a valid PPDU. If another frame (e.g., any other valid frame) is received, the transmission of the MPDU is considered to have failed.

[0043] According to some embodiments, the auxiliary link can initiate PPDU transmission only when the STA in the primary link attached to the same MLD initiates PPDU as the TXOP holder at the same start time. However, during synchronous transmission on the NSTR link pair, the transmission failure of the MPDU may occur on any link of the NSTR link pair. When the AP MLD operates on the NSTR link pair, error recovery can be selectively performed. According to some embodiments, synchronous transmission on the auxiliary link is suspended during the error recovery on the primary link to advantageously avoid IDC interference and improve the performance of the wireless network.

[0044] A TXOP initiator attached to an NSTRAP MLD or an NSTR non-AP MLD may initiate a frame exchange to synchronously obtain a TXOP on an NSTR link pair. When an MLD of an NSTR link pair fails to obtain a TXOP on a primary link, the TXOP on the secondary link is terminated after the initial frame exchange on the secondary link is successful, and the transmission network allocation vector (TXNAV) timer of the TXOP initiator is reset to zero. In addition, the MLD may perform a new backoff procedure, and contention parameters (e.g., CW[AC] and QSRC[AC]) may remain unchanged. When a TXOP initiator of an MLD on a primary link of an NSTR link pair successfully obtains a TXOP, and another TXOP initiator of the same MLD on a secondary link of the NSTR link pair fails to obtain a TXOP, the MLD may continue the frame exchange on the primary link and end the channel access on the secondary link to wait for the TXOP on the primary link to terminate. The MLD may also perform a new backoff procedure and initiate a new transmission on the secondary link, which is aligned with the start time of a PPDU transmission within an existing TXOP on the primary link.

[0045] Figure 4a An exemplary synchronous transmission 400 of a downlink TXOP initiated by an NSTR AP MLD 405 according to an embodiment of the present invention is depicted, wherein a transmission error occurs on the primary link. AP1 425 and AP2 430 are attached to the same NSTR APMLD 405 (TXOP initiator). STA1 415 and STA2 420 are attached to the same NSTR non-AP MLD 410 (TXOP responder). AP1 425 and AP2 430 perform EDCA backoff 435 and 440 on the primary link and the secondary link, respectively. When the EDCA backoff counters 435 and 440 on both the primary link and the secondary link reach zero, AP1 425 and AP2 430 initiate frame exchange 445 on the primary link and the secondary link with the same start time. When the initial frame exchange of AP1 425 fails because a valid BA response 450 is not received on the primary link, AP2 430 terminates the TXOP after a successful initial frame exchange, and the TXNAV timer of AP2 430 is reset to zero. AP2 430 may perform a new backoff 455 to initiate a new TXOP with AP1 425 in accordance with the channel access rules of the NSTR multi-link operation. The CW[AC] and QSRC[AC] on the secondary link remain unchanged. The initial frame exchange 445 may include a control frame exchange (e.g., RTS / CTS or MU-RTS / CTS).

[0046] Figure 4b An exemplary synchronous transmission 400b of a downlink TXOP initiated by an NSTR AP MLD 405b according to an embodiment of the present invention is depicted, wherein a transmission error occurs on an auxiliary link. AP1 425b and AP2 430b are attached to the same NSTR AP MLD 405b (TXOP initiator). STA1 415b and STA2 420b are attached to the same NSTR non-AP MLD 410b (TXOP responder). AP1 425b and AP2 430b perform EDCA backoff 435b and 440b on the primary link and the auxiliary link, respectively. When the EDCA backoff counters 435b and 440b on both the primary link and the auxiliary link reach zero, AP1 425b and AP2 430b initiate frame exchange 445b on the primary link and the auxiliary link with the same start time. When AP1 425b obtains a TXOP on the primary link, it continues to transmit within the TXOP regardless of the state of the auxiliary link.

[0047] When AP2 430b fails to obtain a TXOP due to a failure in the initial frame exchange on the auxiliary link, if the channel becomes idle, AP2 430b can invoke a new backoff process and count down the backoff counter, and then start a transmission with a start time aligned with the start time of the next transmission of AP1 430b on the primary link within the existing TXOP. The new TXOP obtained by AP2 430b after the backoff process is within the time of the existing TXOP of AP1 425 on the primary link.

[0048] Figure 5 An exemplary synchronous transmission 500 of a downlink TXOP initiated by an NSTR AP MLD according to an embodiment of the present invention is depicted, wherein a transmission error occurs on the primary link and occurs after an initial frame exchange. AP1 525 and AP2 530 are attached to the same NSTR AP MLD (TXOP initiator). STA1 515 and STA2 520 are attached to the same NSTR non-AP MLD 510 (TXOP responder). Figure 5 In the example of , AP1 525 and AP2 530 obtain synchronized TXOPs on the primary link and the secondary link. When the "PHY-RXSTART.indication" primitive (indicating that a valid signal has been received) is not received or detected after the timeout interval of the primary link, the non-initial frame exchange (PPDU2 545+BA2) of AP1 525 fails. Even if the channel is idle during the Priority InterFrame Space (PIFS) time interval after the end of PPDU2 545 on the primary link, AP1 525 does not perform PIFS recovery. AP2 530 terminates the TXOP on the secondary link due to the failure on the primary link after receiving BA2, without using PIFS channel access.

[0049] Figure 6An exemplary synchronous transmission 600 initiated by an NSTR AP MLD 605 for resuming an existing TXOP on a primary link and terminating a TXOP on an auxiliary link according to an embodiment of the present invention is shown. AP1 625 and AP2 630 are attached to the same NSTR AP MLD 605 (TXOP initiator). STA1 615 and STA2 620 are attached to the same NSTR non-AP MLD 610 (TXOP responder). AP1 625 and AP2 630 obtain synchronized TXOPs on the primary link and the auxiliary link. When the "PHY-RXSTART.indication" primitive is not received or detected after a timeout interval PIFS on the primary link, the non-initial frame exchange (PPDU2 645+BA2) fails. AP1 625 can perform a backoff to resume an existing TXOP or start a new TXOP. Transmissions within the resumed TXOP or the new TXOP do not overlap with the response BA2 650 of the auxiliary link. When AP2 630 cannot determine whether the TXOP on the primary link is ongoing before performing the next frame exchange on the secondary link, AP2 630 may terminate the TXOP after receiving the response BA2 650 on the secondary link. The TXNAV NAV timer of AP2 630 may be reset to zero.

[0050] Figure 7An exemplary synchronous transmission 700 of a downlink TXOP initiated by an NSTR AP MLD according to an embodiment of the present invention is depicted, which includes performing a backoff recovery on the primary link. AP1 725 and AP2 730 are attached to the same NSTR APMLD 705 (TXOP initiator). STA1 715 and STA2 720 are attached to the same NSTR non-AP MLD 710 (TXOP responder). AP1 725 and AP2 730 obtain synchronized TXOPs on the primary link and the secondary link. When the "PHY-RXSTART.indication" primitive is not received or detected after a timeout interval PIFS on the primary link, the non-initial frame exchange (PPDU2 745+BA2) of AP1 725 fails. AP1 725 can perform a backoff 760 to recover the existing TXOP. The transmission 745 within the recovered TXOP does not overlap with the response frame BA2 750 on the secondary link. AP2 730 may continue to transmit PPDU3 SIFS 755 after the valid response BA2 750 on the auxiliary link because AP1 725 continues the TXOP after backoff recovery 760 and before AP2 730 decides to transmit PPDU3 755 on the auxiliary link (e.g., backoff recovery 760 of AP1 725 is invoked when the transmission of PPDU2 745 fails and the backoff counter has reached zero). Otherwise, AP2 730 will terminate the TXOP on the auxiliary link.

[0051] Figure 8 An exemplary synchronous transmission 800 of a downlink TXOP initiated by an NSTR AP MLD 805, wherein the TXOP on the secondary link is terminated after a transmission failure on the primary link, is depicted in accordance with an embodiment of the present invention. AP1 825 and AP2 830 are attached to the same NSTR AP MLD 805 (TXOP initiator). STA1 815 and STA2 820 are attached to the same NSTR non-AP MLD 810 (TXOP responder). AP1 825 and AP2 830 obtain synchronized TXOPs on the primary and secondary links. Figure 8 In the example of FIG. 8 , after the corresponding “PHY-RXEND.indication”, AP1 825 does not recognize a valid response frame. AP1 825 may perform PIFS recovery or backoff recovery to continue the existing TXOP. Before AP2 830 must decide whether to transmit subsequent frame exchanges on the secondary link, AP2 830 cannot determine whether the TXOP is still in progress on the primary link, and therefore terminates its own TXOP.

[0052] When a TXOP initiator attached to an NSTR AP MLD or an NSTR non-AP MLD obtains a synchronized TXOP on an NSTR link pair, and a TXOP holder on the primary link of the MLD in the NSTR link pair receives a valid response frame for a non-initial frame, the TXOP holder may continue to transmit within the TXOP. When another TXOP holder on the secondary link of the NSTR link pair by the same MLD fails to receive a valid response frame for a non-initial frame within the TXOP, the TXOP holder on the primary link may also continue to transmit within the TXOP. For example, if a "PHY-RXSTART.indication" primitive is not received or detected during a timeout interval PIFS of the secondary link, the TXOP holder on the secondary link does not perform PIFS after transmitting a non-initial frame and may invoke a backoff.

[0053] If a "PHY-RXSTART.indication" primitive is received or detected during the timeout interval PIFS on the primary link, the TXOP holder on the secondary link waits for the corresponding "PHY-RXEND.indication" primitive to identify a valid response frame. If no valid response frame is identified, the TXOP holder on the secondary link does not perform PIFS recovery and may invoke backoff. When the medium is idle and certain conditions are met, the TXOP holder on the secondary link may continue the existing TXOP after invoking backoff and initiate a transmission / retransmission within the existing TXOP, and align the start time of the initiated transmission / retransmission with the start time of the next transmission on the primary link, wherein the certain conditions include one of the following conditions:

[0054] 1) If the backoff counter of the TXOP holder reaches zero on a slot boundary of the secondary link;

[0055] 2) If the TXOP holder's backoff counter is already zero, and the TXOP holder chooses not to transmit and keeps the backoff counter at zero.

[0056] The TXOP holder on the auxiliary link may also terminate the TXOP at any time due to a frame exchange failure on the auxiliary link, in which case the TXNAV timer of the TXOP holder may be reset to zero.

[0057] Fig. 9An exemplary synchronous transmission 900 of a downlink TXOP initiated by an NSTR AP MLD 905 according to an embodiment of the present invention is depicted, wherein a non-initial frame exchange fails. AP1 925 and AP2 930 are attached to the same NSTR AP MLD 905 (TXOP initiator). STA1 915 and STA2 920 are attached to the same NSTR non-AP MLD 910 (TXOP responder). AP1 925 and AP2 930 obtain synchronized TXOPs on the primary link and the secondary link. When the "PHY-RXSTART.indication" primitive is not received or detected after a timeout interval PIFS of the secondary link, the non-initial frame exchange (PPDU2 950+BA2) of AP2 930 fails. Regardless of the error status on the secondary link, AP1 925 can continue the existing TXOP. AP2 930 can terminate the TXOP without recovering from the PIFS error on the secondary link.

[0058] Fig.10 An exemplary synchronous transmission 1000 of a downlink TXOP initiated by an NSTR AP MLD 1005 in accordance with an embodiment of the present invention is depicted, wherein a non-initial frame exchange fails and error recovery is performed on an auxiliary link. AP1 1025 and AP2 1030 are attached to the same NSTR AP MLD 1005 (TXOP initiator). STA1 1015 and STA2 1020 are attached to the same NSTR non-AP MLD 1010 (TXOP responder). Fig.10 In the example of , AP1 1025 and AP2 1030 obtain synchronized TXOPs on the primary link and the secondary link. When the "PHY-RXSTART.indication" primitive is not received or detected after the timeout interval PIFS of the secondary link, the non-initial frame exchange (PPDU2 1050+BA2) of AP2 1030 fails. Regardless of the error status on the secondary link, AP1 1025 can continue the existing TXOP, and when the medium is idle and certain conditions are met, AP2 1030 can perform error recovery by calling the backoff process 1055, and initiate transmission / retransmission within the existing TXOP of the secondary link, and align the start time of the initiated transmission / retransmission with the start time of the transmission PPDU3 1060 on the primary link, wherein the certain conditions include one of the following conditions:

[0059] 1) The backoff counter 1055 of AP2 1030 reaches zero on the slot boundary of the auxiliary link;

[0060] 2) The backoff counter 1055 of AP2 1030 is already zero, and AP2 1030 chooses not to transmit and keeps the backoff counter at zero.

[0061] Fig.11 An exemplary synchronous transmission 1100 of a downlink TXOP initiated by an NSTR AP MLD, wherein transmission on the primary link continues after a transmission error on the secondary link, is depicted in accordance with an embodiment of the present invention. AP1 1125 and AP2 1130 are attached to the same NSTR AP MLD 1105 (TXOP initiator). STA1 1115 and STA2 1120 are attached to the same NSTR non-AP MLD 1110 (TXOP responder). AP1 1125 and AP2 1130 obtain synchronized TXOPs on the primary and secondary links. Fig.11 In the example of FIG. 1 , after the timeout interval PIFS of the auxiliary link is not received, and a valid response frame is not recognized on the auxiliary link, the non-initial frame exchange (PPDU1 1150+BA1) of AP2 1130 fails. Regardless of the error status on the auxiliary link, AP1 1125 can continue the existing TXOP, and AP2 1130 can terminate the TXOP. When the medium is idle and certain conditions are met, AP2 1130 can also perform error recovery by invoking a backoff procedure, and initiate transmission / retransmission PPDU2 1155 within the existing TXOP of the auxiliary link, and align the start time of the initiated transmission / retransmission PPDU2 1155 with the start time of transmission PPDU3 1160 on the primary link, wherein the certain conditions include one of the following conditions:

[0062] 1) The backoff counter 1165 of AP2 1130 reaches zero on a slot boundary of the auxiliary link;

[0063] 2) The backoff counter 1165 of AP2 1130 is already zero, and AP2 1130 chooses not to transmit and keeps the backoff counter at zero.

[0064] Fig.12 is a flow chart depicting exemplary steps of a computer-implemented process 1200 for transmitting data in a wireless network over multiple links of an NSTR MLD in accordance with an embodiment of the present invention.

[0065] At step 1205, a first PPDU is transmitted on a first radio link (eg, a primary link) during a first TXOP and a second PPDU is transmitted on a second radio link (eg, an auxiliary link) during a second TXOP.

[0066] At step 1210, a transmission failure is detected on the first wireless link, for example, when a Block Acknowledgement (BA) is not received within a predetermined period of time (timeout interval) or when a "PHY-RXSTART.indication" primitive is not received.

[0067] At step 1215, the second TXOP is terminated in response to a transmission failure on the first wireless link.

[0068] Fig.13 is a flow chart depicting exemplary steps of a computer-implemented process 1300 for transmitting data in a wireless network over multiple links of an NSTR MLD in accordance with an embodiment of the present invention.

[0069] At step 1305 , a first non-initial PPDU is transmitted through a first radio link (eg, a primary link), and a second non-initial PPDU is transmitted through a second radio link (eg, an auxiliary link).

[0070] In step 1310, it is determined that the first non-initial PPDU transmitted on the first radio link in step 1305 includes a transmission error.

[0071] At step 1315, an acknowledgement is received in response to transmitting the second non-initial PPDU on the second radio link.

[0072] At step 1320, after receiving the acknowledgement, a third non-initial PPDU is transmitted over the second radio link.

[0073] At step 1325, a fourth non-initial PPDU is transmitted over the first radio link at substantially the same time as the third non-initial PPDU is transmitted.

[0074] Fig.14 is a flow chart depicting exemplary steps of a computer-implemented process 1400 for transmitting data in a wireless network over multiple links of an NSTR MLD, wherein there is a transmission failure on a secondary link of the MLD, according to an embodiment of the present invention.

[0075] At step 1405, a first PPDU (either an initial frame or a non-initial frame) is transmitted on the primary link during a first TXOP, and a second PPDU (either an initial frame or a non-initial frame) is transmitted on the auxiliary link during a second TXOP.

[0076] At step 1410, it is determined that a second PPDU transmitted on the auxiliary link includes a transmission error.

[0077] At step 1415, during the first TXOP, an acknowledgement is received on the primary link in response to transmitting the first PPDU on the primary link.

[0078] At step 1420, subsequent to the determination at step 1410, a third PPDU is transmitted on the primary link during the first TXOP.

[0079] Exemplary Computer Control System

[0080] Fig.15 An exemplary wireless device 1500 is depicted on which embodiments of the present invention may be implemented. Embodiments of the present invention relate to a multi-link wireless device that can recover from a transmission failure on one wireless link of an NSTR link pair. During synchronous transmission on the NSTR link pair, a transmission failure of an MPDU may occur on either link of the NSTR link pair. The wireless device 1500 can detect a transmission failure on one of the wireless links and perform error recovery, and can manage the timing of synchronous transmissions on another wireless link to advantageously avoid IDC interference and improve performance of the wireless network.

[0081] The wireless device 1500 includes a processor 1505 for running software applications and optionally an operating system. The memory 1510 may include read-only memory and / or random access memory, for example, to store applications and data (e.g., a table of index values) for use by the processor 1505 and data received or transmitted by the radio devices 415 and 420. The radio devices 1515 and 1520 can communicate with other electronic devices over a wireless network (e.g., WLAN) using multiple spatial streams (e.g., multiple antennas), and the radios 1515 and 1520 generally operate according to IEEE standards (e.g., IEEE 802.11ax, IEEE802.11ay, IEEE 802.11be, etc.). The radio devices 1515 and 1520 can perform multi-link operations and can operate on NSTR link pairs. According to some embodiments, the wireless device 1500 may include more than two radio devices. Radio devices (e.g., radio devices 1515 and 1520) can be configured to transmit and / or receive data using multiple different spatial streams based on device capabilities. The wireless device 1500 is operable to perform error recovery operations, including backoff procedures, PIFS recovery, and retransmission, and may end a TXOP, continue a TXOP, or acquire a new TXOP as part of error recovery to advantageously avoid IDC.

[0082] Although the present invention is disclosed as above with preferred embodiments, it is not intended to limit the scope of the present invention. Anyone with ordinary knowledge in the art can make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be based on the scope defined by the patent application.

Claims

1. A method for wireless data transmission in a wireless network, characterized in that: include: transmitting a first physical layer protocol data unit on a first radio link during a first transmission opportunity and transmitting a second physical layer protocol data unit on a second radio link during a second transmission opportunity; detecting a transmission failure on the first wireless link; and terminating the second transmission opportunity in response to detecting a transmission failure on the first wireless link; The first wireless link is a main link of a multi-link device, and the second wireless link is an auxiliary link of the multi-link device.

2. The method for wireless data transmission in a wireless network according to claim 1, characterized in that: Also included is terminating the first transmission opportunity without using priority interframe space channel access in response to detecting a transmission failure on the first wireless link.

3. The method for wireless data transmission in a wireless network as claimed in claim 1, characterized in that: Also included is, in response to detecting a transmission failure on the first radio link, performing a first backoff procedure on the first radio link and performing a second backoff procedure on the second radio link using contention parameters of a previous backoff procedure performed on the second radio link.

4. The method for wireless data transmission in a wireless network according to claim 1, characterized in that: Also included is receiving a first acknowledgement on the second wireless link, and wherein detecting the transmission failure on the first wireless link includes determining that no acknowledgement was received on the first wireless link.

5. The method for wireless data transmission in a wireless network as claimed in claim 4, characterized in that: Also included is setting a transmission network allocation vector timer for the second transmission opportunity associated with the second radio link to zero.

6. The method for wireless data transmission in a wireless network as claimed in claim 3, characterized in that: The first physical layer protocol data unit and the second physical layer protocol data unit include an initial frame exchange of the first transmission opportunity and an initial frame exchange of the second transmission opportunity, respectively.

7. The method for wireless data transmission in a wireless network as claimed in claim 1, characterized in that: The second radio link is configured to initiate a physical layer protocol data unit transmission on the second radio link by the multi-link device as a transmission opportunity holder only when the multi-link device as a transmission opportunity holder performs another physical layer protocol data unit transmission on the first radio link substantially simultaneously.

8. The method for wireless data transmission in a wireless network as claimed in claim 1, characterized in that: The first physical layer protocol data unit and the second physical layer protocol data unit include a non-initial frame exchange of a first transmission opportunity and a non-initial frame exchange of a second transmission opportunity, respectively.

9. The method for wireless data transmission in a wireless network as claimed in claim 1, characterized in that: Also included is receiving an acknowledgment in response to transmitting the second physical layer protocol data unit over the second wireless link.

10. The method for wireless data transmission in a wireless network as claimed in claim 9, characterized in that: Also included is terminating the second transmission opportunity after receiving the acknowledgement on the second radio link in response to detecting a transmission failure on the first radio link.

11. A method for wireless data transmission in a wireless network, characterized in that: include: transmitting a first non-initial physical layer protocol data unit over a first wireless link and transmitting a second non-initial physical layer protocol data unit over a second wireless link; Determining that transmitting the first non-initial physical layer protocol data unit over the first wireless link includes a transmission failure; receiving an acknowledgment in response to transmitting the second non-initial physical layer protocol data unit over the second wireless link; transmitting a third non-initial physical layer protocol data unit over the second wireless link after receiving the acknowledgment; and A fourth non-initial physical layer protocol data unit is transmitted over the first wireless link at substantially the same time as the third non-initial physical layer protocol data unit is transmitted.

12. The method for wireless data transmission in a wireless network according to claim 11, characterized in that: Also included is transmitting the fourth non-initial physical layer protocol data unit on the first radio link after a backoff procedure in response to determining that transmitting the first non-initial physical layer protocol data unit on the first radio link includes a transmission failure.

13. The method for wireless data transmission in a wireless network according to claim 11, characterized in that: In response to a decoding error in response to an acknowledgement of the first non-initial physical layer protocol data unit, the fourth non-initial physical layer protocol data unit is transmitted on the first wireless link after a priority interframe space idle period.

14. A method for wireless data transmission in a wireless network, characterized in that: include: transmitting a first physical layer protocol data unit on a first radio link during a first transmission opportunity and transmitting a second physical layer protocol data unit on a second radio link during a second transmission opportunity; determining that transmission of the second physical layer protocol data unit over the second wireless link includes a transmission error; receiving an acknowledgment in response to transmitting a first physical layer protocol data unit on the first radio link during the first transmission opportunity; and transmitting a third physical layer protocol data unit over the first radio link during the first transmission opportunity and after determining that transmitting the second physical layer protocol data unit over the second radio link includes a transmission error; The first wireless link is a main link of a multi-link device, and the second wireless link is an auxiliary link of the multi-link device.

15. The method for wireless data transmission in a wireless network as claimed in claim 14, characterized in that: Also included is terminating the second transmission opportunity on the second radio link in response to determining that transmitting the second physical layer protocol data unit on the second radio link includes a transmission error.

16. The method for wireless data transmission in a wireless network as claimed in claim 14, characterized in that: Also included is acquiring a new transmission opportunity on the second radio link within a remaining time of the first transmission opportunity on the first radio link in response to determining that transmission of the second physical layer protocol data unit on the second radio link includes a transmission error.

17. The method for wireless data transmission in a wireless network as claimed in claim 14, characterized in that: Also includes: performing a backoff procedure on the second wireless link; and If the medium is idle after performing the backoff procedure and after receiving the most recent acknowledgement on the first radio link, a fourth physical layer protocol data unit is transmitted on the second radio link.

18. The method for wireless data transmission in a wireless network as claimed in claim 14, characterized in that: Also included is performing error recovery on the second wireless link.

19. The method for wireless data transmission in a wireless network as claimed in claim 18, characterized in that: Performing error recovery on the second radio link includes performing a backoff procedure to obtain priority access to the medium without using a priority interframe space channel access on the second radio link.

20. The method for wireless data transmission in a wireless network as claimed in claim 14, characterized in that: The method further includes transmitting a fourth physical layer protocol data unit on the second radio link at a start time substantially the same as that of transmitting the third physical layer protocol data unit on the first radio link after performing a backoff procedure on the second radio link.

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