DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Response to Arguments
Applicant’s arguments, filed April 15, 2026, with respect to the rejections of claims 19-28, 32, 36-38 under 35 U.S.C. §103 have been fully considered and are persuasive. Therefore, the rejection has been withdrawn. However, upon further consideration, a new grounds of rejection is made in view of 35 U.S.C. §103.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claims 19-28, 32, 36-38 are rejected under 35 U.S.C. 103 as being unpatentable over Jang et al. (US 20210315036 A1) in view of Lu et al. (US 20210212118 A1).
Regarding claim 19, Jang et al. teaches a method for operating a device using multi-link in a wireless local area network, the method comprising: performing a first channel access operation on a first link of the multi-link (Paragraph 116, 156, 195, these passages teach performing channel access via backoff/CCA on a link within a multi-link system); performing a second channel access operation on a second link of the multi-link (Paragraph 203–207, 117, these passages teach performing channel access independently on another link using backoff procedures).
Jang et al. does not explicitly teach identifying that a first backoff counter for the first link is zero, determining not to transmit a first frame, and keeping the first backoff counter at zero; and transmitting simultaneously the first frame on the first link and a second frame on the second link, based on a transmission opportunity (TXOP) being obtained on the second link while the first backoff counter is kept at zero and the first link is idle, wherein transmission on one of the first link or the second link causes interference to reception on the other of the first link or the second link.
However, Lu et al. teaches identifying that a first backoff counter for the first link is zero (Paragraph 50, 52, 88, 115, The passage expressly teaches detecting that the backoff timer/counter of the first link has reached zero), determining not to transmit a first frame, and keeping the first backoff counter at zero (Paragraph 50, 52, 54, The passage teaches that after the first link backoff timer reaches zero, transmission is deferred while the timer is maintained at zero awaiting a condition on another link); and transmitting simultaneously the first frame on the first link and a second frame on the second link (Paragraph 50, 52, 88, 117, The passage expressly teaches simultaneous/synchronous transmissions on both links), based on a transmission opportunity (TXOP) being obtained on the second link while the first backoff counter is kept at zero and the first link is idle (Paragraph 50, 52, 80, 88, The passage teaches maintaining the first-link backoff timer at zero, waiting for the second-link backoff timer to reach zero (obtaining TXOP on the second link), verifying the first link remains idle, and then initiating simultaneous transmission), wherein transmission on one of the first link or the second link causes interference to reception on the other of the first link or the second link (Paragraph 35, 40, 44, 58, The passage expressly teaches non-STR links where simultaneous transmission on one link interferes with reception on the other link due to IDC interference).
Therefore, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to provide identifying that a first backoff counter for the first link is zero, determining not to transmit a first frame, and keeping the first backoff counter at zero; and transmitting simultaneously the first frame on the first link and a second frame on the second link, based on a transmission opportunity (TXOP) being obtained on the second link while the first backoff counter is kept at zero and the first link is idle, wherein transmission on one of the first link or the second link causes interference to reception on the other of the first link or the second link as taught by Lu et al. in the system of Jang et al., so that it would enable coordinated multi-link channel access and simultaneous frame transmissions that improve channel utilization, reduce unnecessary contention and backoff delays, and increase overall transmission efficiency in non-simultaneous transmit-and-receive wireless environments where inter-link interference is present.
Regarding claim 20, Jang et al. teaches the device does not support a simultaneous transmit and receive (STR) operation on the first link and the second link (Paragraph 210, 219, 222, teach that when the backoff counter for the second link reaches zero during transmission on the first link, the device defers transmission on the second link until the first link's TXOP ends, demonstrating that it does not support simultaneous transmit and receive (STR) on both links).
Regarding claim 21, Jang et al. teaches based on the first channel access operation being completed on the first link and the second channel access operation not being completed on the second link of the multi-link, determining not to transmit the first frame (Paragraph 210, 220, 222, The cited passages teach that the transmitting STA completes channel access on a first link (aggregated third and fourth links) and, although the backoff counter for the second link reaches zero, it determines not to transmit on the second link because channel access is not yet completed due to ongoing transmission (TXOP) on the first link, thereby deferring transmission).
Regarding claim 22, Jang et al. teaches each of the first channel access operation and the second channel access operation comprises a backoff operation (Paragraph 113, 116, 156, The text describes a backoff-based channel access operation (DCF/EDCA) where each STA performs a backoff procedure before gaining access. [0156] confirms multi-link capability, implying that both links (first and second) would follow similar backoff-based access procedures. This teaches that each link's channel access includes a backoff operation), and wherein success of each of the first channel access operation and the second channel access operation means that a backoff counter value is zero in the backoff operation (Paragraph 135, 144, 145, 155, These passages collectively describe that successful transmission (i.e., channel access) occurs only when the backoff counter reaches zero, which satisfies the condition for initiating transmission. This is equivalent to "success of a channel access operation means that a backoff counter value is zero").
Regarding claim 23, Jang et al. teaches based on the first channel access operation being completed in the first link (Paragraph 218, 221, These passages describe that the transmitting STA has aggregated the third and fourth links (which form the first link 1810), and that it has set a TXOP and transmitted a packet through it) and the second channel access operation not being completed in the second link (Paragraph 219, 220, 222, The second link 1820 is not aggregated and its backoff counter (BC) value is non-zero, indicating the channel access procedure is still in progress and not completed), maintaining a backoff counter value for the first channel access operation as zero (Paragraph 222, 223, While the second link’s BC is held at 0, the first link is in TXOP; its BC remains zero during TXOP).
Regarding claim 24, Jang et al. teaches maintaining the backoff counter value for the first channel access operation as zero until initiation of a new backoff operation (Paragraph 210, 222, 247, These passages teach that once the BC reaches zero, it is held at zero throughout the TXOP and not changed until a new backoff procedure begins).
Regarding claim 25, Jang et al. teaches obtaining the (TXOP) on the second link at a time in that transmission of a frame is possible based on the second channel access operation being successful (Paragraph 202, 212, 213, When the second link’s backoff counter is zero and its channel is idle, the STA aggregates it and transmits, meaning a TXOP is obtained based on successful channel access).
Regarding claim 26, Jang et al. teaches the second channel access operation on the second link includes a second backoff operation (Paragraph 156, 204, 206-209, The second link has its own backoff counter and performs an independent backoff procedure, including counter selection, countdown, and reset—fully teaching a "second backoff operation" as part of its channel access).
Regarding claim 27, Jang et al. teaches managing backoff parameter for a channel access operation in the multi-link for each link (Paragraph 117, 133, These paragraphs teach the general backoff counter mechanism per STA. In a multi-link context, each link of a multi-link STA can be viewed as operating similarly to a separate STA, thereby justifying per-link backoff management).
Regarding claim 28, Jang et al. teaches transmitting the first frame on the first link comprises; performing a third channel access operation on the first link of the multi- link (Paragraph 244, Setting a new TXOP implies performing a new (i.e., third) channel access operation on the first link, including EDCA/backoff); and transmitting the first frame on the first link after the third channel access operation is completed (Paragraph 245, While this example uses the second link, analogous behavior for the first link is shown in [0229]–[0231], where transmission occurs after channel access completes. This teaches transmitting the first frame after the third channel access).
Regarding claim 32, Jang et al. teaches the third channel access operation on the first link is performed at a time that the second channel access operation of the second link stops (Paragraph 224, When the second link finishes its access attempt (BC=0 and channel idle), the STA resumes transmission on the first link, now aggregated with the second link—constituting a third access on the first link. Thus, the third access occurs when the second link’s access stops).
Regarding claim 36, Jang et al. teaches a device using multi-link in a wireless local area network, the device comprising a processor configured to: perform a first channel access operation on a first link of the multi-link (Paragraph 116, 156, 195, these passages teach performing channel access via backoff/CCA on a link within a multi-link system); perform a second channel access operation on a second link of the multi-link (Paragraph 203–207, 117, these passages teach performing channel access independently on another link using backoff procedures).
Jang et al. does not explicitly teach identify that a first backoff counter for the first link is zero, determine not to transmit a first frame, and keep the first backoff counter at zero; and transmit simultaneously the first frame on the first link and a second frame on a second link, based on a transmission opportunity (TXOP) being obtained on the second link while the first backoff counter is kept at zero and the first link is idle, wherein transmission on one of the first link or the second link causes interference to reception on the other of the first link or the second link.
However, Lu et al. teaches identify that a first backoff counter for the first link is zero (Paragraph 50, 52, 88, 115, The passage expressly teaches detecting that the backoff timer/counter of the first link has reached zero), determine not to transmit a first frame, and keep the first backoff counter at zero (Paragraph 50, 52, 54, The passage teaches that after the first link backoff timer reaches zero, transmission is deferred while the timer is maintained at zero awaiting a condition on another link); and transmit simultaneously the first frame on the first link and a second frame on a second link (Paragraph 50, 52, 88, 117, The passage expressly teaches simultaneous/synchronous transmissions on both links), based on a transmission opportunity (TXOP) being obtained on the second link while the first backoff counter is kept at zero and the first link is idle (Paragraph 50, 52, 80, 88, The passage teaches maintaining the first-link backoff timer at zero, waiting for the second-link backoff timer to reach zero (obtaining TXOP on the second link), verifying the first link remains idle, and then initiating simultaneous transmission), wherein transmission on one of the first link or the second link causes interference to reception on the other of the first link or the second link (Paragraph 35, 40, 44, 58, The passage expressly teaches non-STR links where simultaneous transmission on one link interferes with reception on the other link due to IDC interference).
Therefore, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to provide identify that a first backoff counter for the first link is zero, determine not to transmit a first frame, and keep the first backoff counter at zero; and transmit simultaneously the first frame on the first link and a second frame on a second link, based on a transmission opportunity (TXOP) being obtained on the second link while the first backoff counter is kept at zero and the first link is idle, wherein transmission on one of the first link or the second link causes interference to reception on the other of the first link or the second link as taught by Lu et al. in the system of Jang et al., so that it would enable coordinated multi-link channel access and simultaneous frame transmissions that improve channel utilization, reduce unnecessary contention and backoff delays, and increase overall transmission efficiency in non-simultaneous transmit-and-receive wireless environments where inter-link interference is present.
Regarding claim 37, Jang et al. teaches based on the first channel access operation being completed on the first link and the second channel access operation not being completed on the second link of the multi-link, it is the processor is further configured to determine that the transmission of the first frame is not performed (Paragraph 210, 220, 222, The cited passages teach that the transmitting STA completes channel access on a first link (aggregated third and fourth links) and, although the backoff counter for the second link reaches zero, it determines not to transmit on the second link because channel access is not yet completed due to ongoing transmission (TXOP) on the first link, thereby deferring transmission).
Regarding claim 38, Jang et al. teaches based on the first channel access operation being completed on the first link (Paragraph 218, 221, These passages describe that the transmitting STA has aggregated the third and fourth links (which form the first link 1810), and that it has set a TXOP and transmitted a packet through it) and the second channel access operation not being completed in the second link (Paragraph 219, 220, 222, The second link 1820 is not aggregated and its backoff counter (BC) value is non-zero, indicating the channel access procedure is still in progress and not completed), the processor is further configured to maintain a backoff counter value for the first channel access operation as zero (Paragraph 222, 223, While the second link’s BC is held at 0, the first link is in TXOP; its BC remains zero during TXOP).
Allowable Subject Matter
The applicant could consider adding concepts directed to dynamically switching the link on which a backoff operation is performed in response to one link being determined busy, including stopping a first backoff operation on the first link and initiating a second backoff operation on the second link when the second link has been idle for a preset period prior to stoppage of the first backoff operation. Additional concepts could specify that the preset period corresponds to an arbitration interframe space (AIFS), and that a new backoff counter value for the second link is selected within a contention window and is independent of the backoff counter of the first link. The applicant could also incorporate the concept of maintaining a backoff counter at zero on a link that remains idle for the preset period, and conditioning performance of the second backoff operation on both the idle state persisting for the preset period and the backoff counter being maintained at zero. Further concepts may include resuming a backoff operation on a link after its busy state ends based on a remaining backoff counter value from a previously stopped backoff operation, including embodiments where the third backoff operation is selectively performed on either the first or second link depending on which link’s busy state ends. The claim could also reflect preventing frame transmission on one link even if that link is idle for the preset period when a backoff operation is still ongoing on the other link, as well as selecting the link for backoff based on which link’s busy state is expected to end earlier when both links are busy, thereby improving channel capacity and reducing channel access time in multi-link environments where adjacent links experience mutual interference.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Fang et al. (US 20220132611 A1)
Xu et al. (US 20230056461 A1)
BELUR RAMACHANDRA et al. (US 20210185725 A1)
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ANDREW SHAJI KURIAN whose telephone number is (703)756-1878. The examiner can normally be reached Monday-Friday 8am-4pm.
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/ANDREW SHAJI KURIAN/Examiner, Art Unit 2464
/IQBAL ZAIDI/Primary Examiner, Art Unit 2464
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