Preamble puncturing support for wide bandwidth transmission in wireless communications

An apparatus (e.g., an access point (AP)) announces to one or more stations (STAs), in a frame, one or more preamble detection (PD) channels in a frequency segment such that each of the one or more STAs monitors a respective one of the one or more PD channels to detect any transmission on the one or more PD channels. The apparatus then wirelessly communicates with at least one of the one or more STAs on one of the one or more PD channels during a transmission opportunity (TXOP).

TECHNICAL FIELD

The present disclosure is generally related to wireless communications and, more particularly, to preamble puncturing support for wide bandwidth transmission in wireless communications.

BACKGROUND

In a contention-based channel access wireless communications system, devices access the wireless medium in a wideband system, which includes multiple narrow bands (or channels), by sensing a primary 20-MHz channel (which cannot be punctured). The wideband system allows a device to transmit frames on the primary channel and one or more non-primary channels which are idle. A preamble puncturing mechanism can be utilized to increase spectrum usage when there are radar signals, incumbent signals or overlapping basic service set (OBSS) interferences occurring in one or more non-primary channels. In a wireless system under the Institute of Electrical and Electronics Engineers (IEEE) 802.11ax specification, the HE-SIG-A carries a bandwidth (BW) field which indicates the puncturing pattern (at content channel level) in a primary 80-MHz segment with sufficient information about the intended recipients about how to decode the two SIG-B content channels within the [1 2 1 2] encoding structure in the primary 80-MHz segment.

In next-generation wireless systems such as a wireless local area network (WLAN) under the IEEE 802.11be specification, operations in wider bandwidths, such as 320 MHz, 160+160 MHz, 240 MHz, 160+80 MHz, 160 MHz and 80+80 MHz, are supported and, as such, there may be situations in which some smaller-bandwidth devices (e.g., 80-MHz devices) are associated with a wideband-access point (AP) (e.g., a 320-MHz AP). In order to support small-bandwidth devices in a wide-bandwidth system, some small-bandwidth devices may park on non-primary channels to perform frame exchanges. However, when a preamble is allowed to be punctured on non-primary channels (as preamble puncturing is allowed in any 20-MHz channel of a non-primary 80-MHz segment), how a device detects the preamble without causing a large power consumption or missing the detection needs to be addressed. For instance, data transmission on non-punctured channels of a specific non-primary 80-MHz segment might not be detected by devices when the 20-MHz channel for preamble detection is punctured and, as a result, resources could be wasted.

For extreme-high-throughput (EHT) wide-bandwidth transmissions (e.g., in 160 MHz or 320 MHz), information on punctured channel may be carried in a universal signaling field (e.g., U-SIG) for each 80-MHz segment which varies across different 80-MHz segments as puncturing information in a given 80 MHz is specific to only that specific 80 MHz. As an example, two U-SIG fields (U-SIG1and U-SIG2) may be carried in a primary 80 MHz and a secondary 80 MHz, respectively, and they may have different contents as the puncturing patterns in the two 80 MHz may be different. In case that a non-access point (non-AP) station (STA) is or will be parking on the secondary 80 MHz, that non-AP STA would need to detect a preamble on a non-punctured 20-MHz channel in order to obtain the U-SIG information in order to further decode its content. However, when the punctured 20-MHz channel is dynamically changed from one 20-MHz channel to another due to interference or other reason(s), an issue arises as to how an effective transmission can be performed.

SUMMARY

An objective of the present disclosure is to provide schemes, concepts, designs, techniques, methods and apparatuses pertaining to preamble puncturing support for wide bandwidth transmission in wireless communications. Under various proposed schemes in accordance with the present disclosure, it is believed that aforementioned issues may be addressed or otherwise alleviated.

In one aspect, a method may involve announcing, to one or more STAs, in a frame one or more preamble detection (PD) channels in a frequency segment such that each of the one or more STAs monitors a respective one of the one or more PD channels to detect any transmission on the one or more PD channels. The method may also involve wirelessly communicating with at least one of the one or more STAs on one of the one or more PD channels during a transmission opportunity (TXOP).

In another aspect, a method may involve receiving, from an AP, a frame announcing one or more preamble detection (PD) channels in a frequency segment. The method may also involve determining one of the one or more PD channels as a PD channel. The method may further involve monitoring the PD channel to detect a transmission on the PD channel.

It is noteworthy that, although description provided herein may be in the context of certain radio access technologies, networks and network topologies such as, Wi-Fi, the proposed concepts, schemes and any variation(s)/derivative(s) thereof may be implemented in, for and by other types of radio access technologies, networks and network topologies such as, for example and without limitation, Bluetooth, ZigBee, 5th Generation (5G)/New Radio (NR), Long-Term Evolution (LTE), LTE-Advanced, LTE-Advanced Pro, Internet-of-Things (IoT), Industrial IoT (IIoT) and narrowband IoT (NB-IoT). Thus, the scope of the present disclosure is not limited to the examples described herein.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Overview

FIG.1illustrates an example network environment100in which various solutions and schemes in accordance with the present disclosure may be implemented.FIG.2˜FIG.15illustrate examples of implementation of various proposed schemes in network environment100in accordance with the present disclosure. The following description of various proposed schemes is provided with reference toFIG.1˜FIG.15.

Referring toFIG.1, network environment100may involve at least a STA110and a STA120may be communicating wirelessly with each other in accordance with one or more IEEE 802.11 standards (e.g., IEEE 802.11be). Each of STA110(herein interchangeably denoted as “STA1”) and STA120(herein interchangeably denoted as “STA2”) may function as an AP STA or a non-AP STA. Moreover, each of STA110and STA120may perform wide-bandwidth operations. Under various proposed schemes in accordance with the present disclosure, STA110and STA120may be configured to perform preamble puncturing support for wide bandwidth transmission in wireless communications in accordance with various proposed schemes described below. It is noteworthy that, in the present disclosure, the term “primary 20-MHz channel” refers to the 20-MHz channel which can be used for channel access. Additionally, the term “segment” refers to a channel segment including multiple 20-MHz channels. Moreover, the term “primary 80-MHz segment” refers to a 80-MHz segment which includes the primary 20-MHz channel. Furthermore, the term “non-primary 80-MHz segment” refers to a 80-MHz segment which does not include the primary 20-MHz channel.

Under a proposed scheme in accordance with the present disclosure with respect to preamble detection channel selection, an AP (e.g., STA110as an AP STA) may announce a preamble puncturing pattern for non-primary channels in a management frame (e.g., beacon, probe response, association response, or other frame(s)), with the preamble puncturing pattern indicating which channels are not punctured during the transmission.FIG.2illustrates an example scenario200in accordance with the present disclosure. In scenario200, a bitmap pattern of “1” may be used to indicate which 20-MHz channels in a non-primary 80-MHz segment are not punctured during the transmission. Referring to part (A) ofFIG.2, for a non-primary 80-MHz segment, a bitmap of “1100” indicates the two 20-MHz channels with lower channel numbers are not punctured. Referring to part (B) ofFIG.2, for a non-primary 80-MHz segment, a bitmap of “1001” indicates the first and the last 20-MHz channels ordered in channel number are not punctured.

Under the proposed scheme, the AP may change the preamble puncturing pattern periodically or, alternatively, non-periodically as triggered by one or more predefined events (e.g., detection of radar signal(s), load control, avoidance of reaching a power limit, detection of incumbent devices, and/or interference caused by coexistence of other system(s)). Moreover, under the proposed scheme, the updated indication of preamble puncturing pattern may be carried in a management frame (e.g., beacon, probe response, or other frame(s)).

Under the proposed scheme, a non-AP STA (e.g., STA120as a non-AP STA) may request or negotiate the parking segment and preamble puncturing pattern of the non-primary segment through a management frame (e.g., association request/response, parking segment request/response, or the like). The non-AP STA parking in a non-primary 80-MHz segment may select one 20-MHz channel as the preamble detection (PD) channel which is the non-punctured channel indicated in the preamble puncturing pattern to perform preamble detection. The non-AP STA parking in the non-primary 80-MHz may also periodically switch back to the primary 20-MHz channel to receive the updated preamble puncturing pattern of the parked non-primary 80-MHz segment and other non-primary 80-MHz segment through management frames (e.g., beacon, probe response, parking segment switching request/response, or other management frame(s)).FIG.3illustrates an example scenario300in accordance with the present disclosure. In part (A) ofFIG.3, in the non-primary 80-MHz segment with a bitmap of “1100” as the preamble puncturing pattern, the non-AP STA may select one of the two non-punctured 20-MHz channels as the PD channel. In part (B) ofFIG.3, in the non-primary 80-MHz segment with a bitmap of “0100” as the preamble puncturing pattern, the non-AP STA may select the only one non-punctured 20-MHz channel as the PD channel.

Under a proposed scheme in accordance with the present disclosure with respect to transmission with preamble puncturing, an AP (e.g., STA110) may transmit in a non-primary 80-MHz segment in an event that all 20-MHz channels indicated as being non-punctured in the preamble puncturing pattern for the non-primary 80-MHz segment are clear channel assessment (CCA) idle. Other 20-MHz channels which are not indicated as non-punctured in the preamble puncturing pattern for that non-primary 80-MHz segment may be punctured in case CCA status is busy. The AP may not transmit on that non-primary 80-MHz segment in an event that at least one 20-MHz channel indicated as being non-punctured in the preamble puncturing pattern for the non-primary 80-MHz segment is CCA busy.

Under a proposed scheme in accordance with the present disclosure with respect to preamble detection channel switching, a non-AP STA (e.g., STA120) parked on a non-primary 80-MHz segment may perform PD channel switching when the preamble puncturing pattern of the non-primary 80-MHz segment is updated and the current PD channel is not overlapped with the updated non-punctured channel pattern. Otherwise, in an event that the current PD channel is overlapped with the updated non-punctured channel pattern, the non-AP STA may not perform PD channel switching (as there is no need to do so).FIG.4illustrates an example scenario400in accordance with the present disclosure. Referring to part (A) ofFIG.4, the PD channel of the non-AP STA is indicated, when the bitmap of preamble puncturing pattern is “1001”. Referring to part (B) ofFIG.4, when the preamble puncturing pattern is changed from “1001” to “1100”, the non-AP STA may keep the current PD channel since the current PD channel is overlapped with the updated non-punctured channel pattern. Referring to part (C) ofFIG.4, when the preamble puncturing pattern is further changed from “1100” to “0011”, the non-AP STA may switch its PD channel to a different channel that is not punctured according to the new preamble puncturing pattern.

Under the proposed scheme, a non-AP STA parked on a non-primary 80-MHz segment may switch its PD channel and parking segment through a management frame (e.g., parking segment switching announcement, parking segment switching request/response exchange, or other frame(s)) when one or more of a number of predefined conditions are met. Such predefined conditions may include, for example and without limitation: (a) when the preamble puncturing pattern of the non-primary 80-MHz segment is updated; (b) when the non-AP STA does not detect any preamble from its AP on the PD channel in the parked non-primary 80-MHz segment for a timeout period; and (c) when the non-AP STA is subject to a strong interference (e.g., higher than an interference threshold) in the current parked non-primary 80-MHz segment. Under the proposed scheme, the parking switching announcement or request/response frame may indicate the segment number and target switch time.FIG.5illustrates an example scenario500in accordance with the present disclosure. Referring to part (A) ofFIG.5, initially the PD channel of a non-AP STA may be one of the non-punctured channels of a first non-primary 80-MHz segment (denoted as “non-primary 80-MHz segment1” inFIG.5) before PD channel switching. Referring to part (B) ofFIG.5, the new PD channel of the non-AP STA may be switched to one of the non-punctured channels of a second non-primary 80-MHz segment (denoted as “non-primary 80-MHz segment2” inFIG.5) after PD channel switching. In this example, the non-AP STA changes not only its PD channel but also its parking segment (in which the new PD channel is located).

Under a proposed scheme in accordance with the present disclosure with respect to preamble puncturing support in EHT basic service set (BSS), when punctured channel information carried in U-SIG sent in a 80-MHz segment is specific to only that 80-MHz segment, an AP (e.g., STA110) may determine a preamble detection channel for each 80-MHz segment and announce the preamble detection channel(s) to its associated STAs. Given that the punctured channel information carried in U-SIG in each 80-MHz segment is specific to only that 80-MHz segment, at least one 20-MHz channel that cannot be punctured in each 80-MHz segment and thus such 20-MHz channel may be determined to be the PD channel for that 80-MHz segment.FIG.6illustrates an example scenario600in accordance with the present disclosure. In scenario600, in each of a primary 80-MHz segment and a secondary 80-MHz segment, one of the 20-MHz channels serves as the respective PD channel. Moreover, in the primary 80-MHz segment, the PD channel may also be the primary 20-MHz channel.

Under the proposed scheme, the AP may announce the PD channel for each 80-MHz segment (e.g., in a beacon, probe response, association (or re-association) response frame(s) or other management frame(s)). Additionally, the AP may switch the PD channel for each 80-MHz segment (e.g., in an extended channel switching Announcement frame or parking segment switching announcement/request/response frame or other management frame) by appending the preamble detection channel switch element. A value of the preamble detection switch element may indicate the channel position (e.g., with 0 indicating the lowest 20-MHz channel, 1 indicating the second lowest 20-MHz channel, 2 indicating the third lowest 20-MHz channel, and 3 indicating the fourth lowest 20-MHz channel) of the PD channel for each 80-MHz segment.FIG.7illustrates an example scenario700in accordance with the present disclosure. In scenario700, a preamble detection channel switch element is appended to the announcement frame or management frame that is announced by the AP.

In static preamble puncturing, a PD channel may not be utilized in case the PD channel is not idle even though other 60-MHz channels in the 80-MHz segment are idle. Under a proposed scheme in accordance with the present disclosure with respect to dynamic preamble puncturing support in EHT BSS, in order to support dynamic preamble puncturing to adapt to dynamic interference on some 20-MHz channels, an AP may announce a PD channel set for each non-primary segment in management frame (e.g., beacon, probe response, (re)association response, or other frame(s)), with a PD channel set being used by devices parking on a specific non-primary segment to select a PD channel for preamble detection.

Under the proposed scheme, the position of each PD channel (e.g., 20-MHz channel) in the PD channel set in a non-primary segment (e.g., non-primary 80-MHz segment) may be indicated using a PD channel set bitmap.FIG.8illustrates an example scenario800in accordance with the present disclosure. In scenario800, each “0” in the bitmap may represent the punctured (and hence disallowed) channel. For example, “1111” may indicate that all four 20-MHz channels in a non-primary 80-MHz segment are in the PD channel set. As another example, “1001” may indicate that the first and the fourth 20-MHz channels in a non-primary 80-MHz segment are in the PD channel set. As yet another example, “0000” may indicate that there is no PD channel in a non-primary 80-MHz segment. The PD channel set information may be carried in a PD channel set element. The PD channel set information may include, for example and without limitation, PD channel set number, PD channel set bitmap, change count, and so on, as shown inFIG.8.

FIG.9illustrates an example scenario900in accordance with the present disclosure. Scenario900shows an example regarding usage of PD channel set for dynamic preamble puncturing support in EHT BSS. Referring to part (A) ofFIG.9, a bitmap pattern of “1111” may indicate that all four 20-MHz channels in a 80-MHz segment are used for preamble detection. Referring to part (B) ofFIG.9, a bitmap pattern of “1001” may indicate that the 20-MHz channels corresponding to “1” in the 80-MHz segment can be used for preamble detection.

Under a proposed scheme in accordance with the present disclosure with respect to PD channel set update, the AP may update the PD channel set periodically or, alternatively, non-periodically as triggered by one or more of a number of predefined events in a management frame (e.g., beacon, probe response, (re)association response, or other frame(s)). The predefined events may include, for example and without limitation, detection of radar signal(s), load control, avoidance of reaching a power limit, detection of incumbent devices, and/or interference caused by coexistence of other system(s). By default, the AP may configure all 20-MHz channels as PD channels in each non-primary 80-MHz segment without signaling. As such, in an event that the AP does not include any PD channel set information in management frames, the default PD channel set may be used.

Under a proposed scheme in accordance with the present disclosure with respect to PD channel allocation or selection for non-AP STAs, when a non-AP STA (e.g., STA120) decides to park on a non-primary 80-MHz segment, the non-AP STA may be allocated or select one PD channel from the PD channel set. Under the proposed scheme, the allocated/selected PD channel for a non-AP STA may be determined by a certain rule. For instance, the remainder of the mathematical operation x mod y may first be obtained, with x being the association identifier (AID) of a non-AP STA and with y being the number of channels in the PD channel set in a non-primary 80-MHz segment. Then, the remainder may be used to allocate the PD channel from the PD channel set for the non-AP STA. As an example, with the number of channels in the PD channel set being 2, the first channel (e.g., the one with the lowest channel number) would be chosen as the PD channel when the remainder=0 from the mathematical operation of x mod y. Similarly, the second channel would be chosen as the PD channel when the remainder=1 from the mathematical operation of x mod y. Under the proposed scheme, the allocated/selected PD channel for a non-AP STA may also be negotiated by <AID, PD channel> pair through management frames (e.g., (re)association request/response, PD channel request/response, and so on). Afterwards, the allocated/selected PD channel may be indicated in a broadcast by the AP.

Under the proposed scheme, multiple non-AP STAs parking on the same non-primary 80-MHz segment may be allocated to or may select different PD channels in order to spread usage of the PD channel set in the non-primary 80-MHz segment.FIG.10illustrates an example scenario1000in accordance with the present disclosure. Scenario1000shows an example regarding allocation/selection of PD over a PD channel set for dynamic preamble puncturing support in EHT BSS. Referring to part (A) ofFIG.10, with a bitmap pattern of “1111” indicating that all four 20-MHz channels in the non-primary 80-MHz segment are available for preamble detection, each of four STAs (e.g., STA1, STA2, STA3and STA4) may be allocated to or may select a respective one of the four 20-MHz channels as its respective PD channel. Referring to part (B) ofFIG.10, with a bitmap pattern of “1001” indicating that the 20-MHz channels corresponding to “1” in the non-primary 80-MHz segment are available for preamble detection, two of the STAs may be allocated to or may select a respective one of the two available 20-MHz channels as their respective PD channel. In the example shown in part (B) ofFIG.10, STA1and STA3are allocated to one of the two available 20-MHz channels while STA2and STA4are allocated to the other 20-MHz channel.

Under a proposed scheme in accordance with the present disclosure with respect to preamble puncturing support for wide-bandwidth transmissions in EHT, an AP (e.g., STA110) supporting wide operating bandwidths (e.g., 320 MHz) may transmit in the primary 80-MHz segment and one or more non-primary 80-MHz segment(s). Under the proposed scheme, the AP may transmit on a non-primary 80-MHz segment in case that at least one PD channel in the PD channel set for the non-primary segment is CCA idle. On the other hand, the AP may not transmit on a non-primary 80-MHz segment in case that all PD channels in the PD channel set for the non-primary segment are CCA busy. Under the proposed scheme, the AP may transmit downlink (DL) frame(s) or may trigger uplink (UL) transmission(s) for a non-AP STA (e.g., STA120) whose allocated/selected PD channel is not punctured. On the other hand, the AP may not transmit DL frame(s) or trigger UL transmission(s) for a non-AP STA whose allocated/selected PD channel is punctured.

FIG.11illustrates an example scenario1100in accordance with the present disclosure. Specifically, scenario1100shows an example of punctured TXOP. In scenario1100, an AP obtains a TXOP with preamble puncturing some of the non-primary channels. Specifically, in scenario1100, all four 20-MHz channels of a non-primary 80-MHz segment are PD channels. Four STAs, including STA1, STA2, STA3and STA4, are parked on the non-primary 80-MHz segment and each selects a respective one of the four 20-MHz channels in the non-primary 80-MHz segment as its PD channel. When STA3's PD channel is punctured and when the AP obtains a punctured TXOP, the AP would transmit to STA1, STA2and STA4except for STA3.

Under a proposed scheme in accordance with the present disclosure with respect to preamble puncturing support for PD channel switching in EHT, a non-AP STA (e.g., STA120) may monitor its PD channel to detect transmission(s) in the non-primary 80-MHz segment. The non-AP STA may also monitor or request for an update of PD channel set for a non-primary segment (e.g., via beacon, probe response, (re)association request/response, PD channel switching request/response, and the like). The non-AP STA may switch its PD channel based on the updated PD channel set, if and when an update is received. Under the proposed scheme, under certain circumstances, the non-AP STA may switch back to the primary 20-MHz channel to update its PD channel by PD channel switching request or monitoring beacon (or other frame(s)) indicating the update of PD channel set (e.g., so that non-AP STAs may switch back to the primary 20-MHz channel to update their respective PD channel by monitoring beacon(s)) in which AP indicates the update of PD channel set). For instance, the non-AP STA may switch back to the primary 20-MHz channel to update its PD channel in case that: (a) the non-AP STA does not detect any preamble from its associated AP on the allocated/selected PD channel for a timeout period, and/or (b) in case that the non-AP STA experiences strong interference (e.g., higher than an interference threshold) in its current PD channel. Moreover, PD channel switching may be signaled with <AID, PD channel> pair based on the current or updated PD channel set.

Under the proposed scheme, the PD channel(s) in each non-primary 80-MHz segment may also be dynamically switched in each TXOP by exchanging EHT (multiuser (MU)-)/request-to-send (RTS)/clear-to-send (CTS) frame(s) before sending the preamble punctured Physical Layer Conformance Procedure (PLCP) Protocol Data Units (PPDUs). Under the proposed scheme, an EHT (MU-) RTS frame may contain the PD channel information for each non-primary 80-MHz segment that indicates the 20-MHz channel(s) which is/are not punctured during the TXOP. A non-AP STA may monitor the primary 20-MHz channel in the primary 80-MHz segment to receive the EHT (MU-) RTS frame, which may indicate resource allocation (e.g., by indicating that the non-primary segment where the resource is allocated to the intended recipient and indicating the PD channel(s)) for that non-primary segment). Accordingly, after receiving the EHT (MU-) RTS frame, the non-AP STA may switch its PD channel from the primary 20-MHz channel to the specific channel indicated in the EHT (MU-) RTS frame during the TXOP.

FIG.12illustrates an example scenario1200in accordance with the present disclosure. Specifically, scenario1200shows an example of dynamic PD channel switching in a TXOP. In scenario1200, initially, the PD channel of the secondary 80-MHz segment is the lowest 20-MHz channel. However, due to the PD channel of the secondary 80-MHz segment being busy, the TXOP holder (e.g., AP) dynamically switches the PD channel to the fourth lowest 20-MHz channel in the secondary 80-MHz segment by signaling PD channel switch information to indicate such a change in an EHT RTS frame. As for an intended recipient (e.g., a non-AP STA) of the EHT RTS frame, upon decoding the EHT RTS on the primary 20-MHz channel in the primary 80-MHz segment, it may switch to the new PD channel (e.g., the fourth lowest 20-MHz channel in the secondary 80-MHz segment) as indicated in the EHT RTS frame.

Under a proposed scheme in accordance with the present disclosure with respect to CCA reset on a PD channel, a non-AP STA (e.g., STA120) parking on a non-primary channel (e.g., in a non-primary 80-MHz) may detect preambles on its PD channel. When a detected preamble is an OBSS PPDU, under certain circumstances, a medium access control layer (MAC) entity of the non-AP STA may issue a CCA reset request to its physical layer (PHY) entity (e.g., PHY-CCARESET.request primitive). For instance, the MAC entity of the non-AP STA may issue a CCA reset request to its PHY entity in response to occurrence of one or more of the following: (a) the OBSS PPDU with a received signal strength indication (RSSI) being less than an energy detection threshold, (b) a carrier lost indication (e.g., PHY-RXEND.indication(CarrierLost) primitive) being generated by the PHY entity prior to the end of a given period, and (c) a format violation indication (e.g., PHY-RXEND.indication(FormatViolation) primitive) being generated by the PHY entity prior to the end of this period. After the MAC entity issues the PHY-CCARESET.request primitive to reset the PHY entity to a state appropriate for the end of a received frame (e.g., PPDU) and to initiate a new CCA evaluation cycle, the non-AP STA may be able to detect new preamble(s) on its PD channel to receive PPDU(s) sent by its associated AP.

Under a proposed scheme in accordance with the present disclosure with respect to PD channel switching delay, a non-AP STA (e.g., STA120) may perform CCA after switching to a new PD channel or a new parking segment until a frame (e.g., PPDU) is detected by which the non-AP STA can set its network allocation vector (NAV) to synchronize with the new PD channel. Under the proposed scheme, after the switching delay, an AP may perform DL transmission(s) to a non-AP STA which is switching to its new PD channel or a new parking segment. Moreover, after the switching delay and/or NAV synchronization delay, the AP may trigger UL transmission(s) to a non-AP STA which is switching to its new PD channel or a new parking segment.

Illustrative Implementations

FIG.13illustrates an example system1300having at least an example apparatus1310and an example apparatus1320in accordance with an implementation of the present disclosure. Each of apparatus1310and apparatus1320may perform various functions to implement schemes, techniques, processes and methods described herein pertaining to preamble puncturing support for wide bandwidth transmission in wireless communications, including the various schemes described above with respect to various proposed designs, concepts, schemes, systems and methods described above as well as processes described below. For instance, apparatus1310may be implemented in STA110and apparatus1320may be implemented in STA120, or vice versa.

Each of apparatus1310and apparatus1320may be a part of an electronic apparatus, which may be a non-AP STA or an AP STA, such as a portable or mobile apparatus, a wearable apparatus, a wireless communication apparatus or a computing apparatus. When implemented in a non-AP STA, each of apparatus1310and apparatus1320may be implemented in a smartphone, a smart watch, a personal digital assistant, a digital camera, or a computing equipment such as a tablet computer, a laptop computer or a notebook computer. Each of apparatus1310and apparatus1320may also be a part of a machine type apparatus, which may be an IoT apparatus such as an immobile or a stationary apparatus, a home apparatus, a wire communication apparatus or a computing apparatus. For instance, each of apparatus1310and apparatus1320may be implemented in a smart thermostat, a smart fridge, a smart door lock, a wireless speaker or a home control center. When implemented in or as a network apparatus, apparatus1310and/or apparatus1320may be implemented in a network node, such as an AP in a WLAN.

In some implementations, each of apparatus1310and apparatus1320may be implemented in the form of one or more integrated-circuit (IC) chips such as, for example and without limitation, one or more single-core processors, one or more multi-core processors, one or more reduced-instruction set computing (RISC) processors, or one or more complex-instruction-set-computing (CISC) processors. In the various schemes described above, each of apparatus1310and apparatus1320may be implemented in or as a non-AP STA or an AP STA. Each of apparatus1310and apparatus1320may include at least some of those components shown inFIG.13such as a processor1312and a processor1322, respectively, for example. Each of apparatus1310and apparatus1320may further include one or more other components not pertinent to the proposed scheme of the present disclosure (e.g., internal power supply, display device and/or user interface device), and, thus, such component(s) of apparatus1310and apparatus1320are neither shown inFIG.13nor described below in the interest of simplicity and brevity.

In some implementations, apparatus1310may also include a transceiver1316coupled to processor1312. Transceiver1316may include a transmitter capable of wirelessly transmitting and a receiver capable of wirelessly receiving data. In some implementations, apparatus1320may also include a transceiver1326coupled to processor1322. Transceiver1326may include a transmitter capable of wirelessly transmitting and a receiver capable of wirelessly receiving data.

In some implementations, apparatus1310may further include a memory1314coupled to processor1312and capable of being accessed by processor1312and storing data therein. In some implementations, apparatus1320may further include a memory1324coupled to processor1322and capable of being accessed by processor1322and storing data therein. Each of memory1314and memory1324may include a type of random-access memory (RAM) such as dynamic RAM (DRAM), static RAM (SRAM), thyristor RAM (T-RAM) and/or zero-capacitor RAM (Z-RAM). Alternatively, or additionally, each of memory1314and memory1324may include a type of read-only memory (ROM) such as mask ROM, programmable ROM (PROM), erasable programmable ROM (EPROM) and/or electrically erasable programmable ROM (EEPROM). Alternatively, or additionally, each of memory1314and memory1324may include a type of non-volatile random-access memory (NVRAM) such as flash memory, solid-state memory, ferroelectric RAM (FeRAM), magnetoresistive RAM (MRAM) and/or phase-change memory.

Each of apparatus1310and apparatus1320may be a communication entity capable of communicating with each other using various proposed schemes in accordance with the present disclosure. For illustrative purposes and without limitation, a description of capabilities of apparatus1310, as STA110(e.g., an AP STA), and apparatus1320, as STA120(e.g., a non-AP STA), is provided below. It is noteworthy that, although the example implementations described below are provided in the context of WLAN, the same may be implemented in other types of networks.

Under a proposed scheme pertaining to preamble puncturing support for wide bandwidth transmission in wireless communications in accordance with the present disclosure, with apparatus1310implemented in or as STA110and apparatus1320implemented in or as STA120in network environment100in accordance with one or more of IEEE 802.11 standards, processor1312of apparatus1310may announce, via transceiver1316, to one or more STAs (e.g., including apparatus1320as a STA) in a frame (e.g., a management frame) one or more PD channels in a frequency segment (e.g., one or more channels that are not punctured during a TXOP) such that each of the one or more STAs monitors a respective one of the one or more PD channels to detect any transmission on the one or more PD channels. Additionally, processor1312may wirelessly communicate, via transceiver1316, with at least one of the one or more STAs on one of the one or more PD channels during the TXOP.

In some implementations, in announcing the one or more PD channels, processor1312may announce a preamble puncturing pattern indicating, in each of one or more non-primary frequency segments, one or more channels that are not punctured during the TXOP such that each of the one or more STAs monitors one of the one or more channels in one of the one or more non-primary frequency segments as a respective PD channel to detect any transmission on the respective PD channel. Alternatively, in announcing the one or more PD channels, processor1312may announce a PD channel set indicating, in each of one or more non-primary frequency segments, one or more channels that are dedicated for the one or more STAs during the TXOP such that each of the one or more STAs monitors one of the one or more channels in one of the one or more non-primary frequency segments as the respective PD channel to detect any transmission on the respective PD channel.

In some implementations, the one or more non-primary frequency segments may include one or more non-primary 80-MHz frequency segments not including a 20-MHz primary channel on which channel access is performed. In such cases, in wirelessly communicating with the at least one of the one or more STAs, processor1312may perform one or more of the following: (a) transmitting on one of the one or more non-primary 80-MHz frequency segments in an event that at least one PD channel in the PD channel set for the one of the one or more non-primary 80-MHz frequency segments is CCA idle; (b) not transmitting on the one of the one or more non-primary 80-MHz frequency segments in an event that all PD channels in the PD channel set for the one of the one or more non-primary 80-MHz frequency segments are CCA busy; (c) transmitting a DL frame to the at least one of the one or more STAs or triggering an UL transmission from the at least one of the one or more STAs in an event that the PD channel of the at least one of the one or more STAs is not punctured; and (d) not transmitting the DL frame to the at least one of the one or more STAs or triggering the UL transmission from the at least one of the one or more STAs in an event that the PD channel of the at least one of the one or more STAs is punctured.

In some implementations, the frequency segment may include a non-primary 80-MHz frequency segment which does not include a 20-MHz primary channel on which channel access is performed. In such cases, in wirelessly communicating with the at least one of the one or more STAs, processor1312may transmit on the frequency segment in an event that all of a plurality of 20-MHz channels in the frequency segment, which are indicated as being not punctured in the preamble puncturing pattern, are CCA idle. In some cases, in wirelessly communicating with the at least one of the one or more STAs, processor1312may transmit on the frequency segment in an event that at least one of a plurality of 20-MHz channels in the frequency segment, which is indicated as being not punctured in the preamble puncturing pattern, is CCA idle. Alternatively, in wirelessly communicating with the at least one of the one or more STAs, processor1312may not transmit on the frequency in an event that at least one of the plurality of 20-MHz channels in the frequency segment, which is indicated as being not punctured in the preamble puncturing pattern, is CCA busy.

In some implementations, the frequency segment may include a non-primary 80-MHz frequency segment which does not include a 20-MHz primary channel on which channel access is performed. Moreover, the management frame may include a beacon, a probe response, an association response, or a re-association response. In some implementations, in announcing the one or more PD channels, processor1312may exchange control frames (e.g., EHT RTS and CTS frames) at a beginning of the TXOP with the one or more STAs to dynamically update the one or more PD channels in the frequency segment for the TXOP. In such cases, in wireless communicating, processor1312may transmit one or more preamble punctured PPDUs to the one or more STAs.

In some implementations, in wirelessly communicating with the at least one of the one or more STAs, processor1312may perform at least one of the following operations: (a) performing a DL transmission to the at least one of the one or more STAs after the at least one of the one or more STAs switching to a different PD channel in a same or a different frequency segment; and (b) triggering an UL transmission from the at least one of the one or more STAs after the at least one of the one or more STAs switching to the different PD channel in the same or the different frequency segment.

In some implementations, processor1312may perform additional operations. For instance, processor1312may update the preamble puncturing pattern to a new preamble puncturing pattern indicating one or more different channels in the frequency segment that are not punctured during a subsequent transmission. Moreover, processor1312may transmit, on a primary channel on which channel access is performed, an update indicating the new preamble puncturing pattern.

In some implementations, in updating the preamble puncturing pattern, processor1312may update the preamble puncturing pattern periodically. Alternatively, processor1312may update the preamble puncturing pattern non-periodically as triggered by one or more of detection of a radar signal, load control, avoidance of reaching a power limit, detection of one or more incumbent devices, and interference caused by coexistence of one or more other system.

Under another proposed scheme pertaining to preamble puncturing support for wide bandwidth transmission in wireless communications in accordance with the present disclosure, with apparatus1310implemented in or as STA110and apparatus1320implemented in or as STA120in network environment100in accordance with one or more of IEEE 802.11 standards, processor1322of apparatus1320may receive, via transceiver1326, from an AP (e.g., apparatus1310) a frame (e.g., a management frame) announcing one or more PD channels in a frequency segment (e.g., one or more channels that are not punctured during a transmission). Additionally, processor1322may determine one of the one or more PD channels as a PD channel. Moreover, processor1322may monitor the PD channel to detect a transmission on the PD channel.

In some implementations, in receiving the frame announcing the one or more PD channels, processor1322may receive a preamble puncturing pattern indicating, in each of one or more non-primary frequency segments, one or more channels that are not punctured during a TXOP such that each of one or more STAs to which the frame is transmitted monitors one of the one or more channels in one of the one or more non-primary frequency segments as a respective PD channel to detect any transmission on the respective PD channel. Alternatively, in receiving the frame announcing the one or more PD channels, processor1322may receive a PD channel set indicating, in each of the one or more non-primary frequency segments, one or more channels that are dedicated for the one or more STAs during the TXOP such that each of the one or more STAs monitors one of the one or more channels in one of the one or more non-primary frequency segments as the respective PD channel to detect any transmission on the respective PD channel.

In some implementations, the one or more non-primary frequency segments may include one or more non-primary 80-MHz frequency segments not including a 20-MHz primary channel on which channel access is performed.

In some implementations, the frequency segment may include a non-primary 80-MHz frequency segment which does not include a 20-MHz primary channel on which channel access is performed. Moreover, the frame may include a beacon, a probe response, an association response, or a re-association response.

In some implementations, processor1322may perform additionally operations. For instance, processor1322may receive, from the AP, an update indicating a new preamble puncturing pattern indicating one or more different channels in the frequency segment that are not punctured during a subsequent transmission. Moreover, responsive to receiving the update, processor1322may switch to one of the one or more different channels as a new PD channel to monitor the new PD channel to detect any transmission on the new PD channel.

In some implementations, processor1322may perform additionally operations. For instance, processor1322may switch to a different frequency segment which does not include a primary channel on which channel access is performed.

In some implementations, in switching, processor1322may perform additional operations. For instance, processor1322may receive a frame (e.g., an EHT RTS frame) from the AP at a beginning of a TXOP indicating the different frequency segment where a resource is allocated and a different PD channel in the different frequency segment. Additionally, processor1322may switch to the different PD channel in the different frequency segment responsive to receiving the frame.

In some implementations, processor1322may perform other operations. For instance, processor1322may transmit, via transceiver1326, an indication of the switching via a parking segment switching announcement or via a parking segment switching request and response exchange. In such cases, in switching to the different frequency segment, processor1322may switch to the different frequency segment responsive to one or more of a plurality of conditions. The plurality of conditions may include: (a) the preamble puncturing pattern having been updated by the AP, (b) no detection of any preamble from the AP on the PD channel for a timeout period, and (c) existence of an interference higher than an interference threshold in the frequency segment.

In some implementations, processor1322may perform additionally operations. For instance, processor1322may switch back to the primary channel. Additionally, processor1322may select the PD channel to a different non-primary channel as a different PD channel. Moreover, processor1322may transmit, to the AP and via transceiver1326, the selected PD channel indicating the selected different PD channel. For instance, non-AP STAs may select a PD channel based on AP-announced non-punctured channel pattern or PD channel set, and each non-AP STA may indicate its selected PD channel to the AP. Alternatively, each non-AP STA may switch to a different PD channel and may indicate the updated PD channel to the AP.

In some implementations, in transmitting the updated PD channel, processor1322may transmit the updated PD channel via a PD channel switching request. Moreover, in updating the PD channel, processor1322may update the PD channel responsive to at least one of the following: (a) no detection of any preamble from the AP on the PD channel for a timeout period, and (b) existence of an interference higher than an interference threshold in the PD channel.

In some implementations, processor1322may perform additionally operations. For instance, processor1322may detect, on the PD channel, a preamble of an OBSS PPDU. Moreover, a MAC of processor1322may issue a CCA reset request to a PHY of apparatus1320responsive to at least one of a plurality of conditions being met. In some implementations, the plurality of conditions may include the following: (a) the OBSS PPDU having a RSSI being less than an energy detection threshold, (b) a carrier lost indication being generated by the PHY prior to an end of a given period, and (c) a format violation indication being generated by the PHY prior to the end of the given period.

In some implementations, processor1322may perform additionally operations. For instance, processor1322may switch to a different PD channel or a different frequency segment. Furthermore, processor1322may perform at least one of the following: (a) receiving a DL transmission from the AP after a switching delay upon the switching to the different PD channel or the different frequency segment; and (b) performing an UL transmission to the AP after the switching delay or a NAV synchronization delay upon switching to the different PD channel or the different frequency segment.

Illustrative Processes

FIG.14illustrates an example process1400in accordance with an implementation of the present disclosure. Process1400may represent an aspect of implementing various proposed designs, concepts, schemes, systems and methods described above. More specifically, process1400may represent an aspect of the proposed concepts and schemes pertaining to preamble puncturing support for wide bandwidth transmission in wireless communications in wireless communications in accordance with the present disclosure. Process1400may include one or more operations, actions, or functions as illustrated by one or more of blocks1410and1420. Although illustrated as discrete blocks, various blocks of process1400may be divided into additional blocks, combined into fewer blocks, or eliminated, depending on the desired implementation. Moreover, the blocks/sub-blocks of process1400may be executed in the order shown inFIG.14or, alternatively in a different order. Furthermore, one or more of the blocks/sub-blocks of process1400may be executed repeatedly or iteratively. Process1400may be implemented by or in apparatus1310and apparatus1320as well as any variations thereof. Solely for illustrative purposes and without limiting the scope, process1400is described below in the context of apparatus1310implemented in or as STA110(e.g., AP STA) and apparatus1320implemented in or as STA120(e.g., non-AP STA) of a wireless network such as a WLAN in network environment100in accordance with one or more of IEEE 802.11 standards. Process1400may begin at block1410.

At1410, process1400may involve processor1312of apparatus1310announcing, via transceiver1316, to one or more STAs (e.g., including apparatus1320as a STA) in a frame (e.g., a management frame) one or more PD channels in a frequency segment (e.g., one or more channels that are not punctured during a TXOP) such that each of the one or more STAs monitors a respective one of the one or more PD channels to detect any transmission on the one or more PD channels. Process1400may proceed from1410to1420.

At1420, process1400may involve processor1312wirelessly communicating, via transceiver1316, with at least one of the one or more STAs on one of the one or more PD channels during the TXOP.

In some implementations, in announcing the one or more PD channels, process1400may involve processor1312announcing a preamble puncturing pattern indicating, in each of one or more non-primary frequency segments, one or more channels that are not punctured during the TXOP such that each of the one or more STAs monitors one of the one or more channels in one of the one or more non-primary frequency segments as a respective PD channel to detect any transmission on the respective PD channel. Alternatively, in announcing the one or more PD channels, process1400may involve processor1312announcing a PD channel set indicating, in each of one or more non-primary frequency segments, one or more channels that are dedicated for the one or more STAs during the TXOP such that each of the one or more STAs monitors one of the one or more channels in one of the one or more non-primary frequency segments as the respective PD channel to detect any transmission on the respective PD channel.

In some implementations, the one or more non-primary frequency segments may include one or more non-primary 80-MHz frequency segments not including a 20-MHz primary channel on which channel access is performed. In such cases, in wirelessly communicating with the at least one of the one or more STAs, process1400may involve processor1312performing one or more of the following: (a) transmitting on one of the one or more non-primary 80-MHz frequency segments in an event that at least one PD channel in the PD channel set for the one of the one or more non-primary 80-MHz frequency segments is CCA idle; (b) not transmitting on the one of the one or more non-primary 80-MHz frequency segments in an event that all PD channels in the PD channel set for the one of the one or more non-primary 80-MHz frequency segments are CCA busy; (c) transmitting a DL frame to the at least one of the one or more STAs or triggering an UL transmission from the at least one of the one or more STAs in an event that the PD channel of the at least one of the one or more STAs is not punctured; and (d) not transmitting the DL frame to the at least one of the one or more STAs or triggering the UL transmission from the at least one of the one or more STAs in an event that the PD channel of the at least one of the one or more STAs is punctured.

In some implementations, the frequency segment may include a non-primary 80-MHz frequency segment which does not include a 20-MHz primary channel on which channel access is performed. In such cases, in wirelessly communicating with the at least one of the one or more STAs, process1400may involve processor1312transmitting on the frequency segment in an event that all 20-MHz channels in the frequency segment, which are indicated as being not punctured in the preamble puncturing pattern, are CCA idle. In some cases, in wirelessly communicating with the at least one of the one or more STAs, process1400may involve processor1312transmitting on the frequency segment in an event that at least one of a plurality of 20-MHz channels in the frequency segment, which is indicated as being not punctured in the preamble puncturing pattern, is CCA idle. Alternatively, in wirelessly communicating with the at least one of the one or more STAs, process1400may involve processor1312not transmitting on the frequency segment in an event that at least one of the plurality of 20-MHz channels in the frequency segment, which is indicated as being not punctured in the preamble puncturing pattern, is CCA busy.

In some implementations, the frequency segment may include a non-primary 80-MHz frequency segment which does not include a 20-MHz primary channel on which channel access is performed. Moreover, the management frame may include a beacon, a probe response, an association response, or a re-association response.

In some implementations, in announcing the one or more PD channels, process1400may involve processor1312exchanging control frames at a beginning of the TXOP with the one or more STAs to dynamically update the one or more PD channels in the frequency segment for the TXOP. In such cases, in wireless communicating, process1400may involve processor1312transmitting one or more preamble punctured PPDUs to the one or more STAs. In some implementations, the control frames may include EHT RTS and CTS frames.

In some implementations, in wirelessly communicating with the at least one of the one or more STAs, process1400may involve processor1312performing at least one of the following operations: (a) performing a DL transmission to the at least one of the one or more STAs after the at least one of the one or more STAs switching to a different PD channel in a same or a different frequency segment; and (b) triggering an UL transmission from the at least one of the one or more STAs after the at least one of the one or more STAs switching to the different PD channel in the same or the different frequency segment.

In some implementations, process1400may involve processor1312performing additional operations. For instance, process1400may involve processor1312updating the preamble puncturing pattern to a new preamble puncturing pattern indicating one or more different channels in the frequency segment that are not punctured during a subsequent transmission. Moreover, process1400may involve processor1312transmitting, on a primary channel on which channel access is performed, an update indicating the new preamble puncturing pattern.

In some implementations, in updating the preamble puncturing pattern, process1400may involve processor1312updating the preamble puncturing pattern periodically. Alternatively, process1400may involve processor1312updating the preamble puncturing pattern non-periodically as triggered by one or more of detection of a radar signal, load control, avoidance of reaching a power limit, detection of one or more incumbent devices, and interference caused by coexistence of one or more other system.

FIG.15illustrates an example process1500in accordance with an implementation of the present disclosure. Process1500may represent an aspect of implementing various proposed designs, concepts, schemes, systems and methods described above. More specifically, process1500may represent an aspect of the proposed concepts and schemes pertaining to preamble puncturing support for wide bandwidth transmission in wireless communications in wireless communications in accordance with the present disclosure. Process1500may include one or more operations, actions, or functions as illustrated by one or more of blocks1510,1520and1530. Although illustrated as discrete blocks, various blocks of process1500may be divided into additional blocks, combined into fewer blocks, or eliminated, depending on the desired implementation. Moreover, the blocks/sub-blocks of process1500may be executed in the order shown inFIG.15or, alternatively in a different order. Furthermore, one or more of the blocks/sub-blocks of process1500may be executed repeatedly or iteratively. Process1500may be implemented by or in apparatus1310and apparatus1320as well as any variations thereof. Solely for illustrative purposes and without limiting the scope, process1500is described below in the context of apparatus1310implemented in or as STA110(e.g., AP STA) and apparatus1320implemented in or as STA120(e.g., non-AP STA) of a wireless network such as a WLAN in network environment100in accordance with one or more of IEEE 802.11 standards. Process1500may begin at block1510.

At1510, process1500may involve processor1322of apparatus1320receiving, via transceiver1326, from an AP (e.g., apparatus1310) a frame (e.g., a management frame) announcing one or more PD channels in a frequency segment (e.g., one or more channels that are not punctured during a transmission). Process1500may proceed from1510to1520.

At1520, process1500may involve processor1322determining one of the one or more PD channels as a PD channel. Process1500may proceed from1520to1530.

At1530, process1500may involve processor1322monitoring the PD channel to detect a transmission on the PD channel.

In some implementations, in receiving the frame announcing the one or more PD channels, process1500may involve processor1322receiving a preamble puncturing pattern indicating, in each of one or more non-primary frequency segments, one or more channels that are not punctured during a TXOP such that each of one or more STAs to which the frame is transmitted monitors one of the one or more channels in one of the one or more non-primary frequency segments as a respective PD channel to detect any transmission on the respective PD channel. Alternatively, in receiving the frame announcing the one or more PD channels, process1500may involve processor1322receiving a PD channel set indicating, in each of the one or more non-primary frequency segments, one or more channels that are dedicated for the one or more STAs during the TXOP such that each of the one or more STAs monitors one of the one or more channels in one of the one or more non-primary frequency segments as the respective PD channel to detect any transmission on the respective PD channel.

In some implementations, the one or more non-primary frequency segments may include one or more non-primary 80-MHz frequency segments not including a 20-MHz primary channel on which channel access is performed.

In some implementations, the frequency segment may include a non-primary 80-MHz frequency segment which does not include a 20-MHz primary channel on which channel access is performed. Moreover, the frame may include a beacon, a probe response, an association response, or a re-association response.

In some implementations, process1500may involve processor1322performing additionally operations. For instance, process1500may involve processor1322receiving, from the AP, an update indicating a new preamble puncturing pattern indicating one or more different channels in the frequency segment that are not punctured during a subsequent transmission. Moreover, responsive to receiving the update, process1500may involve processor1322switching to one of the one or more different channels as a new PD channel to monitor the new PD channel to detect any transmission on the new PD channel.

In some implementations, process1500may involve processor1322performing additionally operations. For instance, process1500may involve processor1322switching to a different frequency segment which does not include a primary channel on which channel access is performed.

In some implementations, process1500may involve processor1322performing additional operations. For instance, process1500may involve processor1322receiving a frame (e.g., an EHT RTS frame) from the AP at a beginning of a TXOP indicating the different frequency segment where a resource is allocated and a different PD channel in the different frequency segment. Additionally, process1500may involve processor1322switching to the different PD channel in the different frequency segment responsive to receiving the frame.

In some implementations, process1500may involve processor1322performing other operations. For instance, process1500may involve processor1322transmitting, via transceiver1326, an indication of the switching via a parking segment switching announcement or via a parking segment switching request and response exchange. In such cases, in switching to the different frequency segment, process1500may involve processor1322switching to the different frequency segment responsive to one or more of a plurality of conditions. The plurality of conditions may include: (a) the preamble puncturing pattern having been updated by the AP, (b) no detection of any preamble from the AP on the PD channel for a timeout period, and (c) existence of an interference higher than an interference threshold in the frequency segment.

In some implementations, process1500may involve processor1322performing additionally operations. For instance, process1500may involve processor1322switching back to the primary channel. Additionally, process1500may involve processor1322selecting the PD channel to a different non-primary channel as a different PD channel. Moreover, process1500may involve processor1322transmitting, to the AP and via transceiver1326, the selected PD channel indicating the different PD channel.

In some implementations, in transmitting the updated PD channel, process1500may involve processor1322transmitting the updated PD channel via a PD channel switching request. Moreover, in updating the PD channel, process1500may involve processor1322updating the PD channel responsive to at least one of the following: (a) no detection of any preamble from the AP on the PD channel for a timeout period, and (b) existence of an interference higher than an interference threshold in the PD channel.

In some implementations, process1500may involve processor1322performing additionally operations. For instance, process1500may involve processor1322detecting, on the PD channel, a preamble of an OBSS PPDU. Moreover, process1500may involve processor1322issuing a CCA reset request to a PHY of apparatus1320responsive to at least one of a plurality of conditions being met. In some implementations, the plurality of conditions may include the following: (a) the OBSS PPDU having a RSSI being less than an energy detection threshold, (b) a carrier lost indication being generated by the PHY prior to an end of a given period, and (c) a format violation indication being generated by the PHY prior to the end of the given period.

In some implementations, process1500may involve processor1322performing additionally operations. For instance, process1500may involve processor1322switching to a different PD channel or a different frequency segment. Furthermore, process1500may involve processor1322performing at least one of the following: (a) receiving a DL transmission from the AP after a switching delay upon the switching to the different PD channel or the different frequency segment; and (b) performing an UL transmission to the AP after the switching delay or a NAV synchronization delay upon switching to the different PD channel or the different frequency segment.

Additional Notes