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 .
Information Disclosure Statement
The information disclosure statements (IDS) submitted on 09/07/2023 and 08/08/2024 are in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statements have been considered by the examiner.
Specification
The lengthy specification has not been checked to the extent necessary to determine the presence of all possible minor errors. Applicant’s cooperation is requested in correcting any errors of which applicant may become aware in the specification.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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 1,3, 5, 7-12, 15-18, and 20 are rejected under 35 U.S.C. 103 as being unpatentable over Ratnam et al. (US 2024/0365379 A1, provisional application no. 63/461,834), hereinafter referred to as Ratnam, in view of Chu et al. (US 2020/0304173 A1), hereinafter referred to as Chu.
Regarding claim 1, Ratnam teaches an apparatus comprising logic and circuitry (Ratnam – Paragraph [0035], provisional page 3, note one or more of the APs may include circuitry and/or programming for facilitating synchronizing OBSS transmissions for multi-AP coordination) configured to cause a first Access Point (AP) to:
determine a joint restricted Target Wake Time (r-TWT) Service Period (SP) for Multi-AP (M-AP) operation with a second AP over a wide channel Bandwidth (BW) comprising a primary channel of the first AP and a primary channel of the second AP (Ratnam – Paragraph [0004], provisional page 8, note BSSs that have an overlap in their respective operating channels (20 MHz primary channel, see Paragraph [0050], provisional page 7), Overlapping BSS (OBSS); Paragraph [0085], provisional page 13, note each of the coordinating APs may schedule a restricted TWT (rTWT) service period (SP) in their respective BSS such that the rTWT SPs are aligned in time with each other);
obtain a Transmit Opportunity (TxOP) over at least the primary channel of the first AP, the TxOP to cover at least the beginning of the joint r-TWT SP (Ratnam – Paragraph [0050], provisional page 7, note any device in that BSS is allowed to initiate transmission if the primary channel is sensed as IDLE, the transmission is normally restricted to that primary 20 MHz and the duration of the transmission is called a transmit opportunity (TXOP) duration; Paragraph [0101], provisional page 18, note the coordination SP can be dedicated to a cluster of coordinating APs, during its own coordination SP, any of the 3 APs may become the sharing AP, i.e., the TXOP owner, while and the other APs among the set {AP1, AP2, AP3} may perform multi-AP coordination as a shared APs);
refrain from transmission over the wide channel BW during a first predefined time period from the beginning of the joint r-TWT SP (Ratnam – Paragraph [0065], provisional page 9, note restricted TWT offers a protected service period for its member STAs by sending Quiet elements to other STAs in the BSS which are not member of the rTWT schedule, where the Quiet interval (period of time where no transmissions occur) corresponding to the Quiet element overlaps with the initial portion of the restricted TWT SP; Paragraph [0094], provisional page 15, note the sharing AP may schedule a quiet interval or an rTWT SP that aligns with the start time of a coordination SP, this can be to end transmissions in its own BSS so that the sharing AP can initiate multi-AP coordination); and
transmit an M-AP trigger frame over the wide channel BW, wherein the M-AP trigger frame is configured to trigger the M-AP operation over the wide channel BW (Ratnam – Paragraph [0105], provisional page 20, note neighbor AP2 sends a trigger frame to request taking control of the TXOP, the coordinating AP1 may end its ongoing transmission and may allow AP2 to perform the multi-AP coordination for the TXOP as the sharing AP).
Ratnam does not teach transmitting an M-AP trigger frame over the wide channel BW based on a determination that a Clear-Channel-Assessment (CCA) state of the primary channel of the second AP is idle for a duration of a second predefined time period during the first predefined time period.
In an analogous art, Chu teaches transmitting an M-AP trigger frame over the wide channel BW based on a determination that a Clear-Channel-Assessment (CCA) state of the primary channel of the second AP is idle for a duration of a second predefined time period during the first predefined time period (Chu – Paragraph [0190], note determining that a primary subchannel of the slave AP is idle, comprising determining that the PHY CCA indicates the primary subchannel is idle a predetermined time period (e.g., SIFS or another suitable time period) before the slave AP is to begin transmitting (e.g., a trigger frame, a DL C-OFDMA transmission, etc.)).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to incorporate the teachings of Chu into Ratnam in order to transmit the trigger frame based on CCA indicating that the primary channel is idle, allowing APs of neighboring networks to coordinate the use of sub-channels (Chu – Paragraphs [0004] and [0190]).
Regarding claim 3, the combination of Ratnam and Chu, specifically Ratnam teaches the apparatus configured to cause the first AP to end a transmission over the primary channel of the first AP at the beginning of the joint r-TWT SP (Ratnam – Paragraph [0094], provisional page 15, note the sharing AP may schedule a quiet interval or an rTWT SP that aligns with the start time of a coordination SP, this can be to end transmissions in its own BSS so that the sharing AP can initiate multi-AP coordination).
Regarding claim 5, the combination of Ratnam and Chu, specifically Ratnam teaches the apparatus configured to allow the first AP to transmit the M-AP trigger frame based on a determination that the first AP is to perform a role of a sharing AP for the joint r-TWT SP (Ratnam – Paragraph [0101], provisional page 18, note the coordination SP can be dedicated to a cluster of coordinating APs, during its own coordination SP, any of the 3 APs may become the sharing AP, i.e., the TXOP owner, while and the other APs among the set {AP1, AP2, AP3} may perform multi-AP coordination as a shared APs; Paragraph [0105], provisional page 20, note neighbor AP2 sends a trigger frame to request taking control of the TXOP, the coordinating AP1 may end its ongoing transmission and may allow AP2 to perform the multi-AP coordination for the TXOP as the sharing AP).
Regarding claim 7, the combination of Ratnam and Chu, specifically Ratnam teaches wherein the first predefined time period comprises a Point Coordination Function (PCF) Inter-Frame-Space (PIFS) (Ratnam – Paragraph [0050], provisional page 7, note if any non-primary channel of the BSS (i.e., a 20 MHz channel that lies within the operating bandwidth but is not the primary channel) is also sensed as IDLE for a Point coordination function Inter Frame Spacing (PIFS) duration before the time when the transmit opportunity starts on the primary channel for a WiFi device, the device can additionally also transmit on that non-primary channel).
Regarding claim 8, Ratnam does not teach wherein the second predefined time period is shorter than the first predefined time period.
In an analogous art, Chu teaches wherein the second predefined time period is shorter than the first predefined time period (Chu – Paragraph [0190], note determining that the PHY CCA indicates the primary subchannel is idle a predetermined time period (e.g., SIFS or another suitable time period) before the slave AP is to begin transmitting (e.g., a trigger frame, a DL C-OFDMA transmission, etc.); it would have been obvious to one of ordinary skill in the art to define a suitable time period to achieve the desired feature).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to incorporate the teachings of Chu into Ratnam for the same reason as claim 1 above.
Regarding claim 9, Ratnam does not teach wherein the second predefined time period is equal to the first predefined time period.
In an analogous art, Chu teaches wherein the second predefined time period is equal to the first predefined time period (Chu – Paragraph [0190], note determining that the PHY CCA indicates the primary subchannel is idle a predetermined time period (e.g., SIFS or another suitable time period) before the slave AP is to begin transmitting (e.g., a trigger frame, a DL C-OFDMA transmission, etc.); it would have been obvious to one of ordinary skill in the art to define a suitable time period to achieve the desired feature).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to incorporate the teachings of Chu into Ratnam for the same reason as claim 1 above.
Regarding claim 10, Ratnam does not teach wherein the second predefined time period comprises a Short Inter-Frame-Space (SIFS).
In an analogous art, Chu teaches wherein the second predefined time period comprises a Short Inter-Frame-Space (SIFS) (Chu – Paragraph [0190], note determining that the PHY CCA indicates the primary subchannel is idle a predetermined time period (e.g., SIFS or another suitable time period) before the slave AP is to begin transmitting (e.g., a trigger frame, a DL C-OFDMA transmission, etc.)).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to incorporate the teachings of Chu into Ratnam for the same reason as claim 1 above.
Regarding claim 11, Ratnam does not teach wherein the second predefined time period comprises a Point Coordination Function (PCF) Inter-Frame-Space (PIFS).
In an analogous art, Chu teaches wherein the second predefined time period comprises a Point Coordination Function (PCF) Inter-Frame-Space (PIFS) (Chu – Paragraph [0190], note determining that a PHY CCA indicates the primary subchannel is idle a predetermined time period (e.g., PIFS or another suitable time period))).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to incorporate the teachings of Chu into Ratnam for the same reason as claim 1 above.
Regarding claim 12, the combination of Ratnam and Chu, specifically Ratnam teaches the apparatus configured to cause the first AP to coordinate the joint r-TWT SP with the second AP (Ratnam – Paragraph [0094], provisional page 15, note the sharing AP may schedule a quiet interval or an rTWT SP that aligns with the start time of a coordination SP, this can be to end transmissions in its own BSS so that the sharing AP can initiate multi-AP coordination).
Regarding claim 15, Ratnam teaches wherein the primary channel of the first AP comprises a channel BW of at least 20 Megahertz (MHz) (Ratnam – Paragraph [0050], provisional page 7, note a WiFi BSS defines one of the 20 MHz channels of its operating bandwidth as the primary channel).
Ratnam does not teach wherein the wide channel BW comprises a channel BW of at least 40MHz.
In an analogous art, Chu teaches wherein the wide channel BW comprises a channel BW of at least 40MHz (Chu – Paragraph [0003], note the IEEE 802.11n Standard permits aggregation of two 20 MHz sub-channels to form a 40 MHz aggregate communication channel).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to incorporate the teachings of Chu into Ratnam for the same reason as claim 1 above.
Regarding claim 16, the combination of Ratnam and Chu, specifically Ratnam teaches the apparatus comprising at least one radio to transmit the M-AP trigger frame (Ratnam – Fig. 2A; Paragraph [0037], provisional page 3, note the AP 101 includes multiple antennas 204a-204n and multiple transceivers 209a-209n; Paragraph [0038], provisional page 3, note the transceivers 209a-209n up-converts the baseband or IF signals to RF signals that are transmitted via the antennas 204a-204n).
Regarding claim 17, the combination of Ratnam and Chu, specifically Ratnam teaches the apparatus comprising one or more antennas connected to the radio, and a processor to execute instructions of an operating system of the first AP (Ratnam – Fig. 2A; Paragraph [0037], provisional page 3, note the AP 101 includes multiple antennas 204a-204n and multiple transceivers 209a-209n; Paragraph [0039], provisional page 4, note the controller/processor 224 is also capable of executing programs and other processes resident in the memory 229, such as an OS).
Regarding claim 18, the claim is interpreted and rejected for the same reason as claim 1 above, except the claim is written in a non-transitory computer-readable medium (CRM) claim format, which is taught by Ratnam (Ratnam – Paragraph [0011], provisional pages 1-2, note various functions described below can be implemented or supported by one or more computer programs, each of which is formed from computer readable program code and embodied in a computer readable medium, which may include a non-transitory computer readable medium).
Regarding claim 20, the claim is interpreted and rejected for the same reason as claim 3 above.
Claims 13-14 are rejected under 35 U.S.C. 103 as being unpatentable over Ratnam in view of Chu as applied to claim 1 above, and further in view of Oteri et al. (WO 2020/097487 A1), hereinafter referred to as Oteri.
Regarding claim 13, the combination of Ratnam and Chu does not teach the apparatus configured to cause the first AP to perform the M-AP operation over the wide channel BW according to a Fractional Frequency Reuse (FFR) of the wide channel BW.
In an analogous art, Oteri teaches the apparatus configured to cause the first AP to perform the M-AP operation over the wide channel BW according to a Fractional Frequency Reuse (FFR) of the wide channel BW (Oteri – Paragraph [00115], note entire bandwidth (e.g., full spectrum/channel); Paragraph [00182], note AP1 and AP2 may perform AP coordination procedures, AP1 and AP2 may negotiate fractional frequency reuse (FFR) through a centralized controller that communicates with AP1 and AP2).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to incorporate the teachings of Oteri into the combination of Ratnam and Chu in order to allow APs to control bandwidth access by STAs, reducing interference (Oteri – Paragraph [00115]).
Regarding claim 14, the combination of Ratnam and Chu does not teach the apparatus configured to cause the first AP to perform the M-AP operation over the wide channel BW by enabling communication of the first AP with one or more first STAs over the wide channel BW, and restricting communications of the first AP with one or more second STAs to the primary channel of the first AP, wherein the one or more first STAs are within a particular range from the first AP, and wherein the one or more second STAs are not within the particular range from the first AP.
In an analogous art, Oteri teaches the apparatus configured to cause the first AP to perform the M-AP operation over the wide channel BW by enabling communication of the first AP with one or more first STAs over the wide channel BW, and restricting communications of the first AP with one or more second STAs to the primary channel of the first AP, wherein the one or more first STAs are within a particular range from the first AP, and wherein the one or more second STAs are not within the particular range from the first AP (Oteri – Fig. 2; Paragraph [00114], note multiple AP transmission schemes in WLANs may be classified based on coordinated OFDMA, coordinated nulling/beamforming, and coordinated SU/MU transmission; Paragraph [00115], note coordinated OFDMA, the APs 214a, 214b, 214c, 214d may allow its STAs 202a, 202d, 202g, 202j (i.e. cell center STAs) that are not affected by interference to use the entire bandwidth, the APs 214a, 214b, 214c, 214d may limit its STAs 202b, 202c, 202e, 202f, 202h, 202i, 202k, 202I (i.e. cell edge STAs) that may be affected by interference to use only partial frequency bandwidth; cell center STAs are within a particular range, cell edge STAs are not within the particular range (as shown in Fig. 2)).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to incorporate the teachings of Oteri into the combination of Ratnam and Chu for the same reason as claim 13 above.
Allowable Subject Matter
Claims 2, 4, 6, and 19 are objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
The following is a statement of reasons for the indication of allowable subject matter:
Applicant’s dependent claims recite:
the configured to cause the first AP to obtain the TxOP based on a determination that a Contention Period (CP) is to occur over the primary channel of the first AP before the joint r-TWT SP;
the apparatus configured to cause the first AP to ensure that a frame in the transmission over the primary channel of the first AP does not solicit an immediate response from a receiver of the frame; and
the apparatus configured to cause the first AP to determine that the first AP is to perform the role of the sharing AP for the joint r-TWT SP based on an AP role negotiation between the first AP and the second AP.
The limitations above are neither taught nor suggested by the prior art.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Chu et al. (US 2016/0366701 A1) discloses conducting CCA prior to receiving a trigger frame.
Seok et al. (US 2022/0183062 A1) discloses trigger-enabled TWT service periods, and responding to trigger frames only after CCA is performed.
Ajami et al. (US 2023/0087887 A1) discloses an AP transmitting a trigger frame to solicit a trigger-based PPDU when no other members of the r-TWT SP have data to transmit or receive during the r-TWT SP (such as by sensing that the channel has been idle for a threshold duration).
Kondabattini et al. (US 2023/0171700 A1) discloses an AP transmitting a trigger frame to announce delivery of multicast data, and sensing that the wireless medium is idle for at least a SIFS duration before attempting to gain channel access.
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/BAILOR C HSU/Primary Examiner, Art Unit 2461
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