Patent ID: 12193077

DETAILED DESCRIPTION

Multi-channel communication techniques described below are discussed merely for explanatory purposes in the context of wireless local area networks (WLANs) that utilize protocols which are the same as or similar to protocols that are defined by the 802.11 Standard from the Institute of Electrical and Electronics Engineers (IEEE) merely for explanatory purposes. In other embodiments, however, multi-channel communication techniques are utilized in other types of suitable wireless communication systems.

In various embodiments, a WLAN communication channel includes a plurality of component channels that are arranged in one or more channel segments. In some embodiments, the channel segments are contiguous, while in other embodiments the channel segments are non-contiguous, in other words, separated by a frequency gap. In an embodiment, the channel segments are located in different bands, for example, 2.4 GHz, 5 GHz, and 6 GHz bands. In other embodiments, other suitable bands are utilized (e.g., 60 GHz, “sub-1 GHz” or 900 MHz, 3.6 GHz, 4.9 GHz, etc.). In various embodiments, the component channels occupy a 20 MHz bandwidth, 40 MHz bandwidth, 5 MHz bandwidth, or another suitable bandwidth within the corresponding band. In various embodiments, the channel segments include one or more component channels and have a total bandwidth of 20 MHz, 40 MHz, 80 MHz, 160 MHz, 320 MHz, or another suitable total bandwidth.

In various embodiments, a WLAN communication device, for example, an access point (AP), designates the component channels of the WLAN communication channel as “primary” channels or “secondary” channels. The AP utilizes primary channels for various operations, such as for transmission of various management transmissions (e.g., transmissions associated with association of a client station154with the AP114, beacon transmissions by the AP114, operating channel bandwidths switch announcement transmissions, etc.), for conducting clear channel assessment (CCA) procedures, etc. The AP utilizes the primary and/or secondary channels for packet transfers with other WLAN communication devices (e.g., transferring user data to client stations). In an embodiment, the AP generally reserves the primary channel(s) for management operations associated with the WLAN110and does not use the secondary channels for the management operations.

In an embodiment, the WLAN communication channel has only one component channel designated as a primary channel, with remaining component channels designated as secondary channels. In another embodiment, the WLAN communication channel has two or more primary channels, with remaining component channels designated as secondary channels. In some embodiments, at least some of the two or more primary channels are in different bands. For example, a first primary channel is located in the 5 GHz band and a second primary channels is located in the 6 GHz band.

In some embodiments, the AP changes the primary channel from a first component channel to a second component channel. In an embodiment, for example, an AP provides an operating channel for a basic service set (BSS operating channel) for client stations that cannot concurrently utilize the entire BSS operating channel, e.g., the AP provides a 160 MHz BSS operating channel while at least some client stations only support an 80 MHz operating channel. The client stations communicate in different segments of the BSS operating channel (e.g., different 80 MHz segments) and the AP switches the primary channel to serve the client stations communicating in the different segments. In another embodiment, the client station is configured to switch its primary channel.

Before transmitting a media access control protocol data unit (MPDU) via a WLAN communication channel, a first WLAN communication device performs a backoff procedure that includes waiting for an expiration of a backoff timer that corresponds to the primary channel of the WLAN communication channel. In some scenarios, for instance, when switching primary channels, a second WLAN communication device is in the midst of a transmission opportunity (TXOP) and is using (or has reserved) a same component channel to which the primary channel of the first WLAN communication device is to be changed. In some scenarios, the first WLAN communication device may not be able to properly determine whether the component channel is idle or unreserved based on a carrier sense multiple access (CSMA) procedure, for example, when the second WLAN communication device is receiving from a third, “hidden node” WLAN communication device, or when the second WLAN communication device is waiting before transmitting a packet within its TXOP. In these scenarios, the first WLAN communication device may switch its primary channel to the component channel, fail to detect the TXOP of the second WLAN communication device, and begin a transmission that interferes with the TXOP of the second WLAN communication device. In various embodiments, when the primary channel is changed, the AP synchronizes a network allocation vector (NAV) for the component channel that is the new primary channel with other WLAN communication devices that use the component channel, in various embodiments. In an embodiment, for example, the AP starts a NAV synchronization timer and postpones starting the backoff timer until after expiration of the NAV synchronization timer. In some scenarios, the additional “waiting” time of the NAV synchronization timer reduces the likelihood that the AP will attempt to transmit on the new primary channel during the TXOP of another WLAN communication device.

FIG.1is a block diagram of an example wireless local area network (WLAN)110, according to an embodiment. The WLAN110includes an access point (AP)114that comprises a host processor118coupled to a network interface device122. The network interface device122includes one or more medium access control (MAC) processors126(sometimes referred to herein as “the MAC processor126” for brevity) and one or more physical layer (PHY) processors130(sometimes referred to herein as “the PHY processor130” for brevity). The PHY processor130includes a plurality of transceivers134, and the transceivers134are coupled to a plurality of antennas138. Although three transceivers134and three antennas138are illustrated inFIG.1, the AP114includes other suitable numbers (e.g., 1, 2, 4, 5, etc.) of transceivers134and antennas138in other embodiments. In some embodiments, the AP114includes a higher number of antennas138than transceivers134, and antenna switching techniques are utilized.

The network interface device122is implemented using one or more integrated circuits (ICs) configured to operate as discussed below. For example, the MAC processor126is implemented, at least partially, on a first IC, and the PHY processor130is implemented, at least partially, on a second IC, in various embodiments. As another example, at least a portion of the MAC processor126and at least a portion of the PHY processor130are implemented on a single IC. For instance, the network interface device122is implemented using a system on a chip (SoC), where the SoC includes at least a portion of the MAC processor126and at least a portion of the PHY processor130.

In an embodiment, the host processor118includes a processor configured to execute machine readable instructions stored in a memory device (not shown) such as a random access memory (RAM), a read-only memory (ROM), a flash memory, etc. In an embodiment, the host processor118is implemented, at least partially, on a first IC, and the network device122is implemented, at least partially, on a second IC, in various embodiments. As another example, the host processor118and at least a portion of the network interface device122is implemented on a single IC.

In various embodiments, the MAC processor126and/or the PHY processor130of the AP114are configured to generate data units, and process received data units, that conform to a WLAN communication protocol such as a communication protocol conforming to the IEEE 802.11 Standard or another suitable wireless communication protocol. For example, the MAC processor126is configured to implement MAC layer functions, including MAC layer functions of the WLAN communication protocol, and the PHY processor130is configured to implement PHY functions, including PHY functions of the WLAN communication protocol. For instance, the MAC processor126is configured to generate MAC layer data units such as MAC service data units (MSDUs), MAC protocol data units (MPDUs), etc., and provide the MAC layer data units to the PHY processor130. The PHY processor130is configured to receive MAC layer data units from the MAC processor126and encapsulate the MAC layer data units to generate PHY data units such as PHY protocol data units (PPDUs) for transmission via the antennas138. Similarly, the PHY processor130is configured to receive PHY data units that were received via the antennas138, and extract MAC layer data units encapsulated within the PHY data units. The PHY processor130may provide the extracted MAC layer data units to the MAC processor126, which processes the MAC layer data units.

PHY data units are sometimes referred to herein as “packets,” and MAC layer data units are sometimes referred to herein as “frames.”

In connection with generating one or more radio frequency (RF) signals for transmission, the PHY processor130is configured to process (which may include modulating, filtering, etc.) data corresponding to a PPDU to generate one or more digital baseband signals, and convert the digital baseband signal(s) to one or more analog baseband signals, according to an embodiment. Additionally, the PHY processor130is configured to upconvert the one or more analog baseband signals to one or more RF signals for transmission via the one or more antennas138.

In connection with receiving one or more RF signals, the PHY processor130is configured to downconvert the one or more RF signals to one or more analog baseband signals, and to convert the one or more analog baseband signals to one or more digital baseband signals. The PHY processor130is further configured to process (which may include demodulating, filtering, etc.) the one or more digital baseband signals to generate a PPDU.

The PHY processor130includes amplifiers (e.g., a low noise amplifier (LNA), a power amplifier, etc.), a radio frequency (RF) downconverter, an RF upconverter, a plurality of filters, one or more analog-to-digital converters (ADCs), one or more digital-to-analog converters (DACs), one or more discrete Fourier transform (DFT) calculators (e.g., a fast Fourier transform (FFT) calculator), one or more inverse discrete Fourier transform (IDFT) calculators (e.g., an inverse fast Fourier transform (IFFT) calculator), one or more modulators, one or more demodulators, etc.

The PHY processor130is configured to generate one or more RF signals that are provided to the one or more antennas138. The PHY processor130is also configured to receive one or more RF signals from the one or more antennas138.

The MAC processor126is configured to control the PHY processor130to generate one or more RF signals by, for example, providing one or more MAC layer data units (e.g., MPDUs) to the PHY processor130, and optionally providing one or more control signals to the PHY processor130, according to some embodiments. In an embodiment, the MAC processor126includes a processor configured to execute machine readable instructions stored in a memory device (not shown) such as a RAM, a read ROM, a flash memory, etc., to provide at least some of the functionality described herein. In another embodiment, the MAC processor126includes a hardware state machine that provides at least some of the functionality described herein.

In various embodiments, the MAC processor126includes one or more multi-band backoff timers127configured to perform one or more backoff procedures in connection with multiple communication channels in multiple RF bands. The backoff procedure involves waiting a period of time before attempting to use a communication channel, according to an embodiment. In an embodiment, the multi-band backoff timers127include one or more network allocation vector (NAV) counters for monitoring use of multiple communication channels in multiple RF bands, according to an embodiment. For example, when the access point114receives a packet, the MAC processor126sets a NAV counter according to a value in a duration field in a MAC header of the packet, at least in some situations, according to an embodiment. The MAC processor126monitors the NAV counter to determine when the transmission of the packet has ended. Some packets are configured for reserving a channel for a desired time period and the duration field in the MAC header of the packet is set to the desired time period. When receiving such a packet, the MAC processor126sets a NAV counter according to the value in the duration field in a MAC header of the packet. The MAC processor126monitors the NAV counter to determine when the reservation of the channel has ended. In some embodiments, the MAC processor126includes i) one or more NAV counters, and ii) one or more NAV synchronization timers that allow for synchronization after a primary channel change in an operating channel, as described below.

In an embodiment, the MAC processor126and the PHY processor130are configured to operate according to a first WLAN communication protocol (e.g., an IEEE 802.11be Standard, or extremely high throughput (EHT)), and also according to one or more second WLAN communication protocols (e.g., as defined by one or more of the IEEE 802.11n Standard, IEEE 802.11ac Standard, the IEEE 802.11ax Standard and/or other suitable WLAN communication protocols) that are legacy protocols with respect to the first WLAN communication protocol. The one or more second WLAN communication protocols are sometimes collectively referred to herein as a “legacy WLAN communication protocol” or simply “legacy protocol.”

The WLAN110includes a plurality of client stations154. Although three client stations154are illustrated inFIG.1, the WLAN110includes other suitable numbers (e.g., 1, 2, 4, 5, 6, etc.) of client stations154in various embodiments. The client station154includes a host processor158coupled to a network interface device162. The network interface device162includes one or more MAC processors166(sometimes referred to herein as “the MAC processor166” for brevity) and one or more PHY processors170(sometimes referred to herein as “the PHY processor170” for brevity). The PHY processor170includes a plurality of transceivers174, and the transceivers174are coupled to a plurality of antennas178. Although three transceivers174and three antennas178are illustrated inFIG.1, the client station154includes other suitable numbers (e.g., 1, 2, 4, 5, etc.) of transceivers174and antennas178in other embodiments. In some embodiments, the client station154includes a higher number of antennas178than transceivers174, and antenna switching techniques are utilized.

The network interface device162is implemented using one or more ICs configured to operate as discussed below. For example, the MAC processor166is implemented on at least a first IC, and the PHY processor170is implemented on at least a second IC, in various embodiments. As another example, at least a portion of the MAC processor166and at least a portion of the PHY processor170is implemented on a single IC. For instance, the network interface device162is implemented using an SoC, where the SoC includes at least a portion of the MAC processor166and at least a portion of the PHY processor170.

In an embodiment, the host processor158includes a processor configured to execute machine readable instructions stored in a memory device (not shown) such as a RAM, a ROM, a flash memory, etc. In an embodiment, the host processor158is implemented, at least partially, on a first IC, and the network device162is implemented, at least partially, on a second IC, in various embodiments. As another example, the host processor158and at least a portion of the network interface device162is implemented on a single IC.

In various embodiments, the MAC processor166and the PHY processor170of the client device154are configured to generate data units, and process received data units, that conform to the WLAN communication protocol or another suitable communication protocol. For example, the MAC processor166is configured to implement MAC layer functions, including MAC layer functions of the WLAN communication protocol, and the PHY processor170is configured to implement PHY functions, including PHY functions of the WLAN communication protocol. The MAC processor166is configured to generate MAC layer data units such as MSDUs, MPDUs, etc., and provide the MAC layer data units to the PHY processor170. The PHY processor170is configured to receive MAC layer data units from the MAC processor166and encapsulate the MAC layer data units to generate PHY data units such as PPDUs for transmission via the antennas178. Similarly, the PHY processor170is configured to receive PHY data units that were received via the antennas178, and extract MAC layer data units encapsulated within the PHY data units. The PHY processor170may provide the extracted MAC layer data units to the MAC processor166, which processes the MAC layer data units.

The PHY processor170is configured to downconvert one or more RF signals received via the one or more antennas178to one or more baseband analog signals, and convert the analog baseband signal(s) to one or more digital baseband signals, according to an embodiment. The PHY processor170is further configured to process the one or more digital baseband signals to demodulate the one or more digital baseband signals and to generate a PPDU. The PHY processor170includes amplifiers (e.g., an LNA, a power amplifier, etc.), an RF downconverter, an RF upconverter, a plurality of filters, one or more ADCs, one or more DACs, one or more DFT calculators (e.g., an FFT calculator), one or more IDFT calculators (e.g., an IFFT calculator), one or more modulators, one or more demodulators, etc.

The PHY processor170is configured to generate one or more RF signals that are provided to the one or more antennas178. The PHY processor170is also configured to receive one or more RF signals from the one or more antennas178.

The MAC processor166is configured to control the PHY processor170to generate one or more RF signals by, for example, providing one or more MAC layer data units (e.g., MPDUs) to the PHY processor170, and optionally providing one or more control signals to the PHY processor170, according to some embodiments. In an embodiment, the MAC processor166includes a processor configured to execute machine readable instructions stored in a memory device (not shown) such as a RAM, a ROM, a flash memory, etc. to provide at least some of the functionality described herein. In an embodiment, the MAC processor166includes a hardware state machine that provides at least some of the functionality described herein.

In an embodiment, the MAC processor166and the PHY processor170are configured to operate according to the first WLAN communication protocol, and also according to the legacy WLAN communication protocol.

In an embodiment, each of the client stations154-2and154-3has a structure that is the same as or similar to the client station154-1. Each of the client stations154-2and154-3has the same or a different number of transceivers and antennas. For example, the client station154-2and/or the client station154-3each have only two transceivers and two antennas (not shown), according to an embodiment.

In an embodiment, one or both of the client stations154-2and154-3are configured to operate according to the legacy WLAN communication protocol, but not according to the first WLAN communication protocol. Such client stations are referred to herein as “legacy client stations.” Similarly, an access point that is similar to the AP114and is configured to operate according to the legacy WLAN communication protocol, but not according to the first WLAN communication protocol, is referred to herein as a “legacy AP.” More generally, wireless communication devices that are configured to operate according to the legacy WLAN communication protocol, but not according to the first WLAN communication protocol, are referred to herein as a “legacy communication devices.”

FIG.2Ais a diagram of an example PPDU200that the network interface device122(FIG.1) is configured to generate and transmit to one or more client stations154(e.g., the client station154-1), according to an embodiment. The network interface device162(FIG.1) may also be configured to transmit data units the same as or similar to the PPDU200to the AP114. The PPDU200may occupy a 20 MHz bandwidth or another suitable bandwidth. Data units similar to the PPDU200occupy other suitable bandwidth such as 40 MHz, 60 MHz, 80 MHz, 100 MHz, 120 MHz, 140 MHz, 160 MHz, 180 MHz, 200 MHz, etc., for example, or other suitable bandwidths, in other embodiments.

The PPDU200includes a PHY preamble204and a PHY data portion208. The PHY preamble204may include at least one of a legacy portion212and a non-legacy portion216, in at least some embodiments. In an embodiment, the legacy portion212is configured to be processed by legacy communication devices in the WLAN110(i.e., communication devices that operate according to a legacy communication protocol), enabling the legacy communication devices to detect the PPDU200and to obtain PHY information corresponding to the PPDU200, such as a duration of the PPDU200.

FIG.2Bis a diagram of an example PHY preamble220. In an embodiment, the PHY preamble220corresponds to the PHY preamble204. In an embodiment, the PHY preamble220is included in the legacy portion212. In another embodiment, the PHY preamble220is included in the non-legacy portion216. The PHY preamble220includes one or more short training fields (STFs)224, one or more long training field (LTFs)228, and one or more signal fields (SIGs)232. In an embodiment, the STFs224and the LTFs228are used for packet detection, automatic gain control (AGC), frequency offset estimation, channel estimation, etc. In an embodiment, the number of LTFs in the LTFs228correspond to a number of spatial/space-time streams used for transmission of the PPDU200. In an embodiment, the SIGs232are used to signal PHY communication parameters (e.g., a modulation and coding scheme (MCS), a number of spatial streams, a frequency bandwidth, etc.) corresponding to the PPDU200.

In some embodiments, the PHY preamble220omits one or more of the fields224-232. In some embodiments, the PHY preamble220includes one or more additional fields not illustrated inFIG.2B. In some embodiments, the order of the fields224-232is different than illustrated inFIG.2B. In an embodiment, the PPDU200is generated and transmitted as a sequence of orthogonal frequency division multiplexing (OFDM) symbols. In an embodiment, each of the STF224, the LTF228, the SIG232, and the data portion208comprises one or more OFDM symbols.

In an embodiment, the AP114and a plurality of client stations154are configured for multiple user (MU) communication using orthogonal frequency division multiple access (OFDMA) transmissions. In an embodiment, the PPDU200is an MU OFDMA data unit in which independent data streams are transmitted to or by multiple client stations154using respective sets of OFDM tones allocated to the client stations154. For example, in an embodiment, available OFDM tones (e.g., OFDM tones that are not used as DC tones and/or guard tones) are segmented into multiple resource units (RUs), and each of the multiple RUs is allocated to data to one or more client stations154. In an embodiment, the independent data streams in respective allocated RUs are further transmitted using respective spatial streams, allocated to the client stations154, using multiple-input multiple-output (MIMO) techniques. In an embodiment, the PPDU200is an MU-MIMO PHY data unit in which independent data streams are transmitted to multiple client stations154using respective spatial streams allocated to the client stations154.

In an embodiment, an operating communication channel of a communication device in the WLAN110is divided into a plurality of smaller component channels, each corresponding to a width of 20 MHz, or another suitable frequency bandwidth. Multiple component channels are concatenated, or “bonded” to form a wider channel, in some embodiments. For instance, a 40 MHz channel is formed by combining two 20 MHz component channels, an 80 MHz channel is formed by combining two 40 MHz channels, and a 160 MHz channel is formed by combining two 80 MHz channels, in various embodiments. In an embodiment, the operating frequency band is divided into component channels of a width different than 20 MHz. In some embodiments, the component channels are aggregated, as described below.

In an embodiment, the PPDU200has a 20 MHz frequency bandwidth and is transmitted in a 20 MHz channel. In other embodiments, the PPDU200may have a frequency bandwidth of 40 MHz, 80 MHz, 100 MHz, 120 MHz, etc., and is correspondingly transmitted over a 40 MHz, 80 MHz, 100 MHz, 120 MHz, etc., channel, respectively. In some such embodiments, at least a portion of the PPDU200(e.g., at least a legacy portion of the PHY preamble204, or the entirety of the PHY preamble204) is generated by generating a field corresponding to a 20 MHz component channel bandwidth and repeating the field over a number of 20 MHz component channels corresponding to the transmission channel, in an embodiment. For example, in an embodiment in which the PPDU200occupies an 80 MHz channel, at least the legacy portion212corresponding to the 20 MHz component channel bandwidth is replicated in each of four 20 MHz component channels that comprise the 80 MHz channel.

In an embodiment, one or more communication devices in the WLAN110(e.g., the AP114, the client station154, etc.) are configured for various multi-channel operations. In an embodiment corresponding to multi-channel operation, two or more communication channels (also sometimes referred to herein as a “channel segments”) are aggregated to form an aggregate channel for simultaneous transmission or reception over the two or more aggregated communication channels in the WLAN110. For instance, in an embodiment, the AP114is configured to transmit a first signal in a first communication channel segment (sometimes referred to herein as “first channel segment”), and simultaneously transmit a second signal over a second channel segment (sometimes referred to herein as “second channel segment”) where the first and second channel segments do not overlap. In some embodiments, the AP114commences transmission of the first signal and the second signal at a same start time (e.g., synchronously), for example, using multiple RF radios, as described herein. In an embodiment, the AP114is configured to cease transmission of the first signal and the second signal at a same end time. In an embodiment, the AP114is configured to cease transmission of the first signal and the second signal at different end times. In an embodiment, the AP114is configured to receive a first signal in a first channel segment and simultaneously receive a second signal over a second channel segment, wherein the first signal and the second signal have an identical start time. In an embodiment, the first signal and the second signal have identical end times. In another embodiment, the first signal and the second signal have different end times.

In an embodiment corresponding to multi-channel operation, the first channel segment and the second channel segment are non-contiguous, i.e., there is a gap in frequency between the first channel segment and the second channel segment. In another embodiment, the first channel segment and the second channel segment are contiguous, i.e., there is no frequency gap between the first channel segment and the second channel segment. In an embodiment, the first channel segment and the second channel segment are of different frequency bandwidths. In an embodiment, the first channel segment and the second channel segment consist of respective different numbers of component channels. In another embodiment, the first channel segment and the second channel segment are of a same bandwidth and consist of a same number of component channels.

In an embodiment, different communication devices (i.e., the AP114and the client stations154) are configured for operation in different frequency bands. In an embodiment, at least some communication devices (e.g., the AP114and the client station154) in the WLAN110are configured for operation over multiple different frequency bands. Example frequency bands include, a first frequency band corresponding to a frequency range of approximately 2.4 GHz-2.5 GHz (“2 GHz band”), and a second frequency band corresponding to a frequency range of approximately 5 GHz-5.9 GHz (“5 GHz band”) of the RF spectrum. In an embodiment, one or more communication devices within the WLAN may also be configured for operation in a third frequency band in the 6 GHz-7 GHz range (“6 GHz band”). Each of the frequency bands comprises plural component channels which are, in some embodiments, combined within the respective frequency bands to generate channels of wider bandwidths, as described above. In an embodiment corresponding to multi-channel operation over multiple communication channel segments aggregated to form an aggregated communication channel, at least some of the multiple channel segments are in different ones of multiple frequency bands, or the multiple channel segments are within a same frequency band.

In an embodiment, the first WLAN communication protocol permits a greater variety of communication channel configurations than is permitted by the legacy WLAN communication protocol. For example, the legacy WLAN communication protocol permits certain combinations of component channels to form communication channels of certain bandwidths, whereas the first WLAN communication protocol permits additional component channel combinations in addition to the component channel combinations permitted by the legacy WLAN communication protocol. For example, whereas the legacy WLAN communication protocol permits contiguous bandwidths of 20 MHz, 40 MHz, 80 MHz, and 160 MHz and a split frequency bandwidth 80+80 MHz, the first WLAN communication protocol additionally permits contiguous bandwidths of 60 MHz, 100 MHz, 120 MHz, 140 MHz, and split frequency bandwidths of 20+20 MHz, 20+40 MHz, 20+80 MHz, 40+40 MHz, 40+80 MHz, etc., in various embodiments.

In an embodiment, a communication device (e.g., the AP114, the client station154-1, etc.) configured to operate according to the first WLAN communication protocol includes multiple RF radios, where respective ones of the multiple RF radios transmit/receive signals in respective RF channel segments of an aggregate communication channel. In some embodiments, the signals transmitted/received by respective ones of the multiple RF radios are synchronously transmitted/received in contiguous or non-contiguous channel segments. For example, a signal transmitted/received in an 80 MHz-wide channel segment by a first RF radio and a signal in a 40 MHz-wide channel segment is synchronously transmitted/received by a second RF radio, where the 80 MHz-wide and the 40 MHz-wide channel segments form a contiguous 120 MHz channel bandwidth in one embodiment, and form a non-contiguous 80+40 MHz channel bandwidth in another embodiment. In some embodiments, the signals transmitted/received by respective ones of the multiple RF radios are asynchronously transmitted/received in the contiguous or non-contiguous channel segments. In other words, signals transmitted or received by a first RF radio do not need to be synchronized in time with signals transmitted or received by a second RF radio. In an embodiment, for example, a first RF radio of a communication device transmits a first signal while a second RF radio of the communication device simultaneously receives (or transmits) a second signal, where the second RF radio begins transmitting or receiving the second signal after the first RF radio has begun transmitting the first RF signal (see, e.g.,FIG.9).

FIG.3Ais a diagram of an example system architecture300corresponding to a communication device configured for multi-channel operation, according to an embodiment. For instance, in an embodiment, the system architecture300is configured for transmission/reception over aggregated communication channel segments. In an embodiment, the system architecture300corresponds to the AP114. In another embodiment, the system architecture300corresponds to the client station154-1. In various embodiments, the system architecture300is configured for simultaneous transmission and/or reception over the aggregated communication channel. In an embodiment, the system architecture300is configured for synchronous transmission and/or reception over the aggregated communication channel. In an embodiment, the system architecture300is configured for asynchronous transmission and/or reception over the aggregated communication channel. In another embodiment, the system architecture is configured for both synchronous and asynchronous transmission and/or reception over the aggregated communication channel.

In an embodiment, the system architecture300is configured for operation over two communication channel segments and includes a forwarding processor304. The communication device300also includes a single MAC processor308, a first PHY processor316, and a second PHY processor320. The single MAC processor308is coupled to the first PHY processor316and the second PHY processor320. The single MAC processor308exchanges frames with the first PHY processor316and the second PHY processor320. In an embodiment, the MAC layer has an interface, for example, a data service access point (SAP) interface, to a layer above the MAC layer (e.g., a logical link control layer or network layer in the Open Systems Interconnection model). In another embodiment, the interface (i.e., data SAP interface) between the MAC layer and the layer above the MAC layer is integral with the MAC layer.

In an embodiment, the single MAC processor308corresponds to the MAC processor126ofFIG.1. In another embodiment, the single MAC processor308corresponds to the MAC processor166ofFIG.1. In an embodiment, the first PHY processor316and the second PHY processor320correspond to the PHY processor130ofFIG.1. In another embodiment, the first PHY processor316and the second PHY processor320correspond to the PHY processor170ofFIG.1.

The first PHY processor316includes a first baseband signal processor324(Baseband-1) coupled to a first RF radio328(Radio-1). The second PHY processor320includes a second baseband signal processor332(Baseband-2) coupled to a second RF radio336(Radio-2). In an embodiment, the RF radio328and the RF radio336correspond to the transceivers134ofFIG.1. In an embodiment, the RF radio328is configured to operate on a first RF band, and the RF radio336is configured to operate on a second RF band. In another embodiment, the RF radio328and the RF radio336are both configured to operate on the same RF band.

In an embodiment, the MAC processor308generates and parses data corresponding to MAC layer data units (e.g., frames) into a plurality of data streams corresponding to respective communication channel segments. In an embodiment, the frames can be transmitted in any channel segments dynamically, i.e., without a band switch negotiation. The MAC processor308provides the parsed data streams to the Baseband-1324and the Baseband-2332. The Baseband-1324and the Baseband-2332are configured to receive the respective data streams from the MAC processor308, and encapsulate and encode the respective data streams to generate respective baseband signals corresponding to PPDUs. In an embodiment, the respective baseband signals have different bandwidths. The Baseband-1324and the Baseband-2332provide the respective baseband signals to the Radio-1328and the Radio-2336. The Radio-1328and Radio-2336upconvert the respective baseband signals to generate respective RF signals for transmission via the first channel segment and the second channel segment, respectively. The Radio-1328transmits a first RF signal via the first channel segment and the Radio-2336transmits a second RF signal via a second channel segment.

The communication device300also includes synchronization control circuitry340, in some embodiments. The synchronization control circuitry340is configured to ensure that respective transmitted signals over the first channel segment and the second channel segment are synchronized. The synchronization control circuitry340is coupled to the Baseband-1324and the Baseband-2332to ensure that the respective baseband signals are synchronized in time.

The Radio-1328and the Radio-2336are also configured to receive respective RF signals via the first channel segment and the second channel segment, respectively. The Radio-1328and the Radio-2336generate respective baseband signals corresponding to the respective received signals. In an embodiment, the generated respective baseband signals have different bandwidths. The generated respective baseband signals are provided to the respective baseband signal processors Baseband-1324and Baseband-2332. The Baseband-1324and the Baseband-2332generate respective data streams that are provided to the MAC processor308. The MAC processor308processes the respective data streams. In an embodiment, the MAC processor308de-parses the data streams received from the Baseband-1324and the Baseband-2332into a single information bit stream.

In an embodiment, the forwarding processor304is omitted and the MAC processor308is coupled to another suitable processor (e.g., the host processor118(FIG.1)) that performs one or more higher level operations corresponding to data transmission and reception. For instance, in an embodiment, the other processor performs one or more operations corresponding to Layer3and above as characterized in the OSI model.

FIG.3Bis a diagram of an example system architecture350corresponding to a communication device configured for multi-channel operation, according to another embodiment. For instance, in an embodiment, the system architecture350is configured for synchronous and/or asynchronous transmission/reception over aggregated communication channels. In an embodiment, the system architecture350corresponds to the AP114. In another embodiment, the system architecture350corresponds to the client station154-1.

The system architecture350is similar to the system architecture300ofFIG.3A, and like-numbered elements are not discussed in detail for purposes of brevity. The communication device350includes a single MAC processor358coupled to a PHY processor366. The single MAC processor308exchanges frames with the PHY processor366. In an embodiment, the single MAC processor358corresponds to the MAC processor126ofFIG.1. In another embodiment, the single MAC processor358corresponds to the MAC processor166ofFIG.1. In an embodiment, the PHY processor366corresponds to the PHY processor130ofFIG.1. In another embodiment, the PHY processor366corresponds to the PHY processor170ofFIG.1. The PHY processor366includes a single baseband signal processor374. The single baseband signal processor374is coupled to the Radio-1328and the Radio-2336.

In an embodiment, the MAC processor358generates data corresponding to MAC layer data units (e.g., frames) and provides the frames to the baseband signal processor374. The baseband signal processor374is configured to receive frames from the MAC processor358, and parse data corresponding to the frames into a plurality of bit streams. The baseband signal processor374is also configured to encapsulate and encode the respective bit streams to generate respective baseband signals corresponding to PPDUs. In an embodiment, the respective baseband signals have different bandwidths. The baseband signal processor374provides the respective baseband signals to the Radio-1328and the Radio-2336. The Radio-1328and Radio-2336upconvert the respective baseband signals to generate respective RF signals for transmission via the first channel segment and the second channel segment, respectively. The Radio-1820transmits a first RF signal via the first channel segment and the Radio-2336transmits a second RF signal via a second channel segment.

The baseband signal processor374is configured to ensure that respective transmitted signals over the first channel segment and the second channel segment are synchronized. For example, the baseband signal processor374is configured to generate the respective baseband signals such that the respective baseband signals are synchronized in time.

The Radio-1328and the Radio-2336are also configured to receive respective RF signals via the first channel segment and the second channel segment, respectively. The Radio-1328and the Radio-2336generate respective baseband signals corresponding to the respective received signals. In an embodiment, the generated respective baseband signals have different bandwidths. The generated respective baseband signals are provided to the baseband signal processor374. The baseband signal processor374generate respective bit streams, and de-parse the bit streams into a data stream corresponding to frames. The baseband signal processor374provides the frames to the MAC processor358. The MAC processor358processes the frames.

As discussed above, in an embodiment, an operating communication channel of a communication device in the WLAN110is divided into a plurality of smaller component channels. In an embodiment, at least one of the smaller component channels is designated as a primary channel and the remaining component channels are secondary channels. In an embodiment, as described above, the primary channel is utilized for both management transmissions and data transmissions, while secondary channels are used for data transmissions but not management transmissions. A communication device (e.g., the AP114or the client station154-1) operating in the WLAN110utilizes the at least one smaller component channel that is designated as a primary channel for various operations, such as for transmission of various management transmissions (e.g., transmissions associated with association of a client station154with the AP114, beacon transmissions by the AP114, operating channel bandwidths switch announcement transmissions, etc.), for conducting clear channel assessment (CCA) procedures, etc. In an embodiment, an aggregate operating channel of a communication device (e.g., the AP114or the client station154-1) includes multiple primary channels. For example, in an embodiment in which a first channel segment is aggregated with a second channel segment to form an aggregated communication channel, a first component channel in the first channel segment is designated as a first primary channel of the aggregate communication channel and a second component channel in the second channel segment is designated in a second primary channel of the aggregate communication channel. In another embodiment, an aggregate communication channel of a communication device (e.g., the AP114or the client station154-1) includes a single primary channel. For example, in an embodiment in which a first channel segment is aggregated with a second channel segment form an aggregate communication channel, a component channel in one of the first channel segment and the second channel segment is designated as a primary channel of the aggregate communication channel. The other one of the first channel segment and the second channel segment does not include a primary channel, in this embodiment.

FIG.4Ais a diagram of an example operating channel400at a first time, according to an embodiment. In an embodiment, the operating channel400corresponds to an operating channel of the AP114, or of a basic service set (BSS) supported by the AP114. In another embodiment, the operating channel400corresponds to an operating channel of a client station154(e.g., the client station154-1). In other embodiments, the operating channel400is employed by a communication device (e.g., an AP or a client station) in a suitable communication network different from the WLAN110. An operating channel such as the operating channel400that corresponds to an operating channel of an AP or a BSS supported by the AP is sometimes referred to herein as an “AP operating channel” or a “BSS operating channel.” An operating channel such as the operating channel400that corresponds to an operating channel of a client station is sometimes referred to herein as an “STA operating channel.” In the embodiment shown inFIG.4A, the operating channel400corresponds to the AP114and a first client station STA1.

The operating channel400includes a first channel segment410aggregated with a second channel segment420. The first channel segment410occupies a first frequency bandwidth and comprises a first number of component channels, and the second channel segment420occupies a second frequency bandwidth and comprises a second number of component channels. In various embodiments, the first bandwidth of the first channel segment410and the second bandwidth of the second channel segment420are equal or are unequal. In various embodiments, the first number of component channels of the first channel segment410and the second number of composite channels of the second channel segment420are equal or are unequal.

In an embodiment, the first channel segment410and the second channel segment420are non-adjacent in frequency (e.g., are non-contiguous). For example, a gap in frequency exists between the first channel segment410and the second first channel segment420. In various embodiments, the gap is at least 500 kHz, at least 1 MHz, at least 5 MHz, at least 20 MHz, etc. In some embodiments, the first channel segment410and the second channel segment420are located in different bands, for example, 2.4 GHz, 5 GHz, and 6 GHz bands. In other embodiments, other suitable bands are utilized (e.g., 60 GHz, “sub-1 GHz” or 900 MHz, 3.6 GHz, 4.9 GHz, etc.). In another embodiment, the first channel segment410and the second channel segment420are adjacent in frequency (e.g., contiguous). In this embodiment, there is no frequency gap between first channel segment410and the second channel segment420.

In an example embodiment, the first channel segment410has a bandwidth of 80 MHz and the second channel segment420has a bandwidth of 80 MHz. In an embodiment in which the first channel segment410and the second channel segment420are not adjacent in frequency, the operating channel400is sometimes referred to as an 80+80 MHz channel. On the other hand, in an embodiment in which the first channel segment410and the second channel segment420are adjacent in frequency, the operating400is sometimes referred to as 160 MHz channel. In general, communication channels similar to the operating channel400in which the first channel segment and the second channel segment are not adjacent in frequency, the aggregate communication channel is referred to as (bandwidth of the first channel segment)+(bandwidth of the second channel segment) channel. On the other hand, communication channels similar to the operating channel400in which the first channel segment and the second channel segment are adjacent in frequency, or in which the second channel segment420is omitted (i.e., the second channel segment420has a bandwidth of 0 MHz), the aggregate communication channel400is referred to as (the sum of the first channel segment bandwidth and the second channel segment bandwidth) channel. In an embodiment, valid channel configurations of the aggregate communication channel400include: 20 MHz channel, 40 MHz channel, 60 MHz channel, 80 MHz channel, 100 MHz, 120 MHz channel, 140 MHz channel, 160 MHz channel, 320 MHz channel, 20+40 MHz channel, 20+80 MHz channel, 40+80 MHz channel, 20+160 MHz, 40+320 MHz, and so on. In an embodiment, a respective bandwidth of each channel segment410,420is selected from a set of possible channel bandwidths of 20 MHz, 40 MHz and 80 MHz. In other embodiments, other suitable sets of possible bandwidths are utilized.

At the first time shown inFIG.4A, the operating channel400includes a single primary channel. For example, the AP114designates a single component channel of the first channel segment410as a primary channel, in an embodiment. In the illustrated embodiment, a first component channel of the first channel segment410is designated as a first primary channel412. In some embodiments, the operating channel400includes more than two primary channels. For example, more than two component channels of the operating channel400are designated as primary channels, in some embodiments.

The operating channel400also includes secondary channels, in an embodiment. In an embodiment, the AP114designates each component channel of the first channel segment410and the second channel segment420that is not designated as a primary channel as a secondary channel. In the illustrated embodiment, the first channel segment410includes three secondary channels414and the second channel segment420includes three secondary channels424. In other embodiments, the first channel segment410and/or the second channel segment420includes another suitable number (e.g., 0, 1, 2, 4, 5, etc.) of secondary channels414,424. In some embodiments, the number of secondary channels414of the first channel segment410is not equal to the number of secondary channels424of the second channel segment420.

In some embodiments, the AP114generates one or more MAC data units to include i) a first primary channel indication indicating a first location, in the first channel segment410, of the first primary channel and ii) a second primary channel indication indicating a second location, in the second channel segment420, of the second primary channel.

FIG.4Bis a diagram of the operating channel400at a second time, according to an embodiment. At the second time, the primary channel of the operating channel400has been changed to a different component channel. In an embodiment, for example, the AP114designates a second component channel that was previously designated as a secondary channel (e.g., secondary channel424-2) as a second primary channel472and designates the first primary channel412as a secondary channel474. In an embodiment, for example, the AP114utilizes the first primary channel412for at least one of transmitting or receiving MPDUs via the first component channel, before designating the second component channel as the second primary channel472. In an embodiment, when designating a component channel as a primary channel, the AP114creates or initializes one or more backoff timers (e.g., backoff timers127) for the component channel. In an embodiment, when designating a component channel as a secondary channel, the AP114removes or suspends one or more backoff timers. Although the second primary channel472is located in the second segment420in the embodiment shown inFIG.4B, in other embodiments, the second primary channel is located in the first segment410(e.g., at secondary channel414-3).

In an embodiment, legacy client stations that conform to the legacy protocol do not support an operating channel in multiple channel segments or with multiple primary channels. In some embodiments, to facilitate interoperability of the AP114with legacy client stations, the first communication protocol does not permit multiple primary channels in an AP operating channel when the AP operating channel is also supported by the legacy protocol. Accordingly, in an embodiment, the AP114is configured to operate with an AP operating channel that includes a single primary channel when the operating channel is also permitted by the legacy protocol, and to operate with an AP operating channel that includes multiple primary channels when the operating channel is not permitted by the legacy protocol.

In some embodiments, an operating channel of a client station (e.g., the client station154-1) has a bandwidth that is narrower than a bandwidth of an operating channel of the AP114. In an embodiment, a client station154(e.g., the client station154-1) operating with an operating channel that is narrower than an operating channel of the AP114is permitted to operate at any location within the operating channel of the AP114. For example, the client station154-1is permitted to operate with an operating channel that does not cover a primary channel of the AP114. In another embodiment, the client station154(e.g., the client station154-1) operating with an operating channel that is narrower than an operating channel of the AP114is not permitted to operate with an operating channel that does not cover a primary channel of the AP114. In this embodiment, an operating channel of the client station154(e.g., the client station154-1) that is narrower than an operating channel of the AP114operates at a location within the operating channel of the AP114that covers at least one primary channel of the AP114.

In the embodiment shown inFIG.4B, the AP114changes from the first primary channel412(FIG.4A) to the second primary channel472to support a legacy client station STA2that has an operating channel that only includes the second primary channel472and the secondary channel424-1in the second segment420. In an embodiment, the AP114receives an indication of the operating channel of the legacy client station STA2where the operating channel i) does not include any primary channel of the operating channel of the AP114and ii) spans multiple secondary channels of the operating channel of the AP114, and the AP114changes the primary channel in response to the indication.

In some embodiments, the AP114provides an explicit indication of the change in the primary channel to one or more client stations. In an embodiment, the AP114generates one or more MPDUs that include an explicit indication of the designation of the second component channel as the primary channel472. In this embodiment, the AP114transmits the MPDU using at least one of the first component channel and the second component channel. In other words, the AP114transmits the explicit indication via the first primary channel412(e.g., before or after the change), via the second primary channel472(e.g., before or after the change), or via both the first primary channel412and the second primary channel472.

In an embodiment, the AP114generates a bandwidth indication of the bandwidth of the second primary channel472in the second segment420that identifies the second component channel as the second primary channel472. In an embodiment, the AP114generates an MPDU that includes the bandwidth indication. In an embodiment, the bandwidth indication is a field within a MAC header of the MPDU. In another embodiment, the bandwidth indication is a field within a management frame.

In some embodiments, the AP114provides an implicit indication of the change in the primary channel to one or more client stations. In an embodiment, for example, the primary channel (e.g., one of the first primary channel412or the second primary channel472) corresponds to a particular predetermined time period. In various embodiments, the predetermined time period is a service period, for example, a target wake time (TWT) service period.

FIG.5is an example timing diagram500of a backoff timer synchronization after a primary channel change in an operating channel502, in an embodiment. In an embodiment, the operating channel502corresponds to an operating channel of the AP114, or of a basic service set (BSS) supported by the AP114. In an embodiment, the operating channel502corresponds to an operating channel of a client station154(e.g., the client station154-1). In other embodiments, the operating channel502is employed by a communication device (e.g., an AP or a client station) in a suitable communication network different from the WLAN110.

The operating channel502is similar to the operating channel400, but includes four component channels. Although the component channels are shown as being contiguous, in other embodiments, one or more of the component channels are located in different frequency bands and/or are separated by a frequency gap, as described above. In the embodiment shown inFIG.5, the AP114changes the primary channel of the operating channel502at a time t0 and at a time t1, which correspond to start times of a first service period510and a second service period520, respectively. In other embodiments, the AP114changes the primary channel at a different suitable time, for example, in response to an MPDU or PPDU from a client station.

In an embodiment, the first and second service periods510and520correspond to different TWT service periods. During the first service period510, the AP114designates a first component channel as a primary channel512and remaining component channels as secondary channels514-1,514-2, and514-3. During the second service period520, the AP114designates a second component channel (i.e., the secondary channel514-1) as a primary channel522and designates the remaining component channels as secondary channels524-1,524-2, and524-3. Accordingly, the first primary channel512is re-designated as a secondary channel524-3.

Before transmitting MPDUs via the operating channel502, the AP114performs a backoff procedure that includes waiting for an expiration of a backoff timer that corresponds to the primary channel. When the primary channel is changed (e.g., from the primary channel512to522), the AP114synchronizes a backoff timer516, which corresponds to the component channel that is the new primary channel, with other devices that use the component channel, in various embodiments. In an embodiment, for example, the AP114starts a network allocation vector (NAV) synchronization timer515and starts the backoff timer516after expiration of the NAV synchronization timer515. In an embodiment, the backoff timer516is a NAV. In an embodiment, the NAV synchronization timer515and the NAV516correspond to the multi-band backoff timers127(FIG.1). When starting the second service period520at the time t1, the AP114starts a NAV synchronization timer525and starts a backoff timer526after expiration of the NAV synchronization timer525, where the NAV synchronization timer525and backoff timer526correspond to the second primary channel522.

During the NAV synchronization timers515and525, (i.e., while the timers run and before their respective expirations), the AP114monitors the medium of the primary channel for transmissions by other communication devices. In an embodiment, when the AP114does not receive or detect a frame in the medium before the NAV synchronization timer expires (e.g., becomes “0”), the AP starts the backoff timer516. In the embodiment shown inFIG.5, the AP114transmits a PPDU517after expiration of the backoff timer516. When the AP114receives or detects a frame (e.g., MPDU521) in the medium before the NAV synchronization timer expires, the AP114synchronizes the backoff timer526using the detected frame. In an embodiment, for example, the AP114receives the MPDU521that includes a NAV indication via the primary channel522during the NAV synchronization timer525, stops the NAV synchronization timer525, and sets the backoff timer526using the NAV indication. In an embodiment, the NAV indication is a high efficiency (HE) physical layer (PHY) header that includes a duration field. In another embodiment, the NAV indication is included in a suitable field of a PHY header or MAC header that corresponds to the MPDU received during the NAV synchronization timer525.

In various embodiments, the backoff timers516and526are set based on a group of respective backoff parameters, for example, for each access category (AC) (i.e., one of AC_BE (best effort), AC_BK (background), AC_VI (video), AC_VO (voice)), there is a backoff timer (e.g., an instance of the backoff timer516or526), a contention window CW, a contention window minimum (CWmin), a contention window maximum (CWmax), a slot time, an arbitrary inter-frame space number (AIFSN), a quality of service short retry counter (QSRC), and a quality of service long retry counter (QLRC). In an embodiment, the AP114is configured to set the backoff parameters for the backoff timers516and526to values that correspond to a successful frame exchange (e.g., setting a contention window value to CWmin). In another embodiment, the AP114is configured to set the backoff parameters to values that correspond to a service period (i.e., using values corresponding to service period520for backoff timer526). In yet another embodiment, the AP114is configured to set the backoff parameters to values that correspond to the prior primary channel (i.e., using values corresponding to backoff timer516for the backoff timer526).

FIG.6AandFIG.6Bare example timing diagrams600and650for a WLAN communication device configured to use separate groups of backoff timers, i.e. one group of backoff timers (backoff timers for AC_BE, AC_BK, AC_VI, AC_VO), for each primary channel in multiple component channels of a WLAN communication channel602with multiple primary channels, in an embodiment. In an embodiment, the operating channel602corresponds to an operating channel of the AP114, or of a basic service set (BSS) supported by the AP114. In an embodiment, the operating channel602corresponds to an operating channel of a client station154(e.g., the client station154-1). In other embodiments, the operating channel602is employed by a communication device (e.g., an AP or a client station) in a suitable communication network different from the WLAN110. The operating channel602is similar to the operating channel400and operating channel500, but includes four component channels Ch0, Ch1, Ch2, and Ch3 and has multiple primary channels at the same time (i.e., Ch0 and Ch3). Although the component channels are shown as being contiguous, in other embodiments, one or more of the component channels are located in different frequency bands with one (or more) primary channel in each band and/or are separated by a frequency gap, as described above. In an embodiment, for example, the component channels Ch0 and Ch1 are located in a channel segment within a 5 GHz band and the component channels Ch2 and Ch3 are located in a channel segment within a 6 GHz band.

In some embodiments, the AP114(or a client station154) is configured to use multiple primary channels over the operating channel602where each primary channel corresponds to its own group of backoff timers (backoff timers for AC_BE, AC_BK, AC_VI, AC_VO). In the embodiment shown inFIG.6A, the AP114designates component channels Ch0 and Ch3 as primary channels over the operating channel602, corresponding to backoff timers606and636, respectively, and designates component channels Ch1 and Ch2 as secondary channels. In other embodiments, the AP114uses additional or fewer primary channels over a different suitable operating channel.

In an embodiment, the AP114checks an idle/busy status of other primary channels and secondary channels, for example, component channel Ch3 (primary) and component channels Ch1 and Ch2 (secondary), when the backoff timer606expires before performing a transmission. When one or more other component channels are idle within a suitable time period (e.g., a point control function interframe space, distributed control function interframe space) before the backoff timer516expires, the AP114performs, schedules, or triggers an uplink or downlink transmission in the one or more idle component channels. In some embodiments, the backoff timers of any band can be used for the backoff of simultaneous transmission of multiple bands (channel segments). In some embodiments, the backoff timers of a specific channel segment can be used for the backoff of simultaneous transmission of multiple bands (channel segments), while the backoff timers of another channel segment can only be used for the transmission of the channel segment. In an embodiment, the channel segment can be a dedicated channel segment or a channel segment having a lower load compared to other channel segments. In some embodiments, the backoff timers of a channel segment being used for the backoff of simultaneous transmission of multiple bands (channel segments) are toggled backoff timers of the channel segments. In other words, when the backoff timer of the channel segment1 is used for a simultaneous transmission via channel segment1 and channel segment2, then the backoff timer of the channel segment2 is used for a next simultaneous transmission of multiple channel segments. In some embodiments, when a channel segment whose backoff timer is not 0 is used for a simultaneous transmission, the backoff timer of the channel segment will be increased by a random or pseudo-random value, for example, per the current CW. In some embodiments, when the backoff timer of a primary channel related to a channel segment becomes 0, the channel segment is combined with other channel segments whose backoff timers become 0. In an embodiment, for a channel segment with backoff timer being 0, the corresponding secondary channels that are idle are used for the simultaneous transmission. In some embodiments, when a channel segment whose backoff timer becomes 0, the AP114waits until the backoff timer of another channel segment becomes zero for a simultaneous transmission.

In some embodiments, the AP114utilizes only those idle component channels that satisfy corresponding channel bounding rules for transmission. In the embodiment shown inFIG.6A, the AP114determines that component channel Ch2 is busy, component channels Ch0, Ch1, and Ch3 are idle, but that channel bounding rules do not allow for a punctured PPDU. In this embodiment, the AP114transmits an unpunctured downlink PPDU640and receives an unpunctured uplink PPDU642that utilize only the component channels Ch0 and Ch1. After the exchange of the PPDUs640and642, the AP114sets the contention window for both the backoff timer606and the backoff timer636to CWmin to indicate a successful frame exchange.

In the embodiment shown inFIG.6B, the AP114determines that component channel Ch2 is busy, component channels Ch0, Ch1, and Ch3 are idle, and that channel bounding rules allow for a punctured PPDU. In this embodiment, the AP114transmits a punctured downlink PPDU690and receives an unpunctured uplink PPDU692that utilize the component channels Ch0, Ch1, and Ch3. After the exchange of the PPDUs690and692, the AP114sets the contention window for both the backoff timer606and the backoff timer636to CWmin to indicate a successful frame exchange.

FIG.7is an example timing diagrams700for a WLAN communication device configured to use separate sets of backoff timers (i.e. one set of backoff timers for AC_BE, AC_BK, QC_VI, QC_VO) in multiple component primary channels of a WLAN communication channel702, in an embodiment. In an embodiment, the operating channel702corresponds to an operating channel of the AP114, or of a basic service set (BSS) supported by the AP114. In an embodiment, the operating channel702corresponds to an operating channel of a client station154(e.g., the client station154-1). In other embodiments, the operating channel702is employed by a communication device (e.g., an AP or a client station) in a suitable communication network different from the WLAN110. The operating channel702is similar to the operating channel600and includes four component channels Ch0, Ch1, Ch2, and Ch3. Although the component channels are shown as being contiguous, in other embodiments, one or more of the component channels are located in different frequency bands and/or are separated by a frequency gap, as described above.

In some embodiments, the AP114(or a client station154) is configured to use multiple primary channels over the operating channel702where each primary channel corresponds to its own set of backoff timers (i.e. backoff timers for AC_BE, AC_BK, AC_VI, AC_VO). In the embodiment shown inFIG.7, the AP114designates component channels Ch0 and Ch1 as primary channels over the operating channel702, corresponding to backoff timers706and716, respectively, and designates component channels Ch2 and Ch3 as secondary channels. In other embodiments, the AP114uses additional or fewer primary channels over a different suitable operating channel.

In some embodiments, the AP114is configured to set backoff parameters of a primary channel whose backoff timer expires to values according to Enhanced Distributed Control Function Channel Access (EDCA) backoff rules without adjusting the backoff timers of other primary channels. In the embodiment shown inFIG.7, the AP114determines, after expiration of the backoff timer706-1, that component channels Ch0 and Ch1 of the operating channel702are idle. The AP114performs a frame exchange that includes a downlink PPDU720and an uplink PPDU722after the expiration. In an embodiment, after the successful frame exchange, the AP114i) sets the backoff parameters that correspond to the backoff timer706to values corresponding to the successful frame exchange, for example, by setting the contention window to CWmin, and ii) does not change the backoff parameters that correspond to the backoff timer716. On the other hand, the AP114determines, after expiration of the backoff timer706-2, that component channels Ch0 and Ch1 of the operating channel702are idle and performs a frame exchange that includes a downlink PPDU750that has a collision752or other frame exchange failure. In an embodiment, after the failed frame exchange, the AP114i) sets the backoff parameters that correspond to the backoff timer706to values corresponding to an unsuccessful frame exchange, for example, by doubling the contention window and increasing the QLRC, and ii) does not change the backoff parameters that correspond to the backoff timer716.

In some embodiments, the AP114is configured to set backoff parameters of i) a primary channel whose backoff timer expires, and ii) other primary channels, to values according to Enhanced Distributed Control Function Channel Access (EDCA) backoff rules. In an embodiment, after the successful frame exchange, the AP114i) sets the backoff parameters that correspond to the backoff timer706and backoff timer716to values corresponding to the successful frame exchange. In an embodiment, after the failed frame exchange, the AP114i) sets the backoff parameters that correspond to the backoff timer706and the backoff timer716to values corresponding to an unsuccessful frame exchange.

FIG.8is an example timing diagram800for a WLAN communication device configured to suspend a backoff timer, in an embodiment. In an embodiment, the operating channel802corresponds to an operating channel of the AP114, or of a basic service set (BSS) supported by the AP114. In an embodiment, the operating channel802corresponds to an operating channel of a client station154(e.g., the client station154-1). In other embodiments, the operating channel802is employed by a communication device (e.g., an AP or a client station) in a suitable communication network different from the WLAN110. The operating channel802is similar to the operating channel600and includes four component channels Ch0, Ch1, Ch2, and Ch3. Although the component channels are shown as being contiguous, in other embodiments, one or more of the component channels are located in different frequency bands and/or are separated by a frequency gap, as described above.

In some embodiments, when a transmission opportunity (TXOP) holder (e.g., the AP114or a client station154) of a TXOP utilizes a portion of the operating channel802, the AP114suspends the backoff timers in other primary channels of the operating channel802during the TXOP. In an embodiment, for example, when the AP114is not configured to transmit in a first primary channel while simultaneously transmitting in a second primary channel, the AP114suspends the backoff timer for the first primary channel while utilizing the second primary channel. In an embodiment, a WLAN communication device announces whether it can receive frames in one band while it is receiving frames in another band. In the embodiment shown inFIG.8, the backoff timer806that corresponds to primary channel Ch0 expires and the AP114performs a frame exchange during a TXOP810. In this embodiment, the AP114suspends the backoff timer836that corresponds to the primary channel Ch3 during the TXOP810. The AP114resumes the backoff timer836when utilization of the component channel Ch0 has completed.

Similarly, in some embodiments, when a TXOP responder (e.g., the AP114or a client station154) utilizes a portion of the operating channel802, the AP114suspends the backoff timers in other primary channels of the operating channel802during the TXOP. In an embodiment, for example, when the AP114is not configured to transmit in a first primary channel while simultaneously receiving in a second primary channel, the AP114suspends the backoff timer for the first primary channel while utilizing the second primary channel. In an embodiment, a WLAN communication device announces whether it can receive frames in one band while it is transmitting frames in another band.

In some embodiments, the AP114is configured to determine whether a first component channel and a second component channel are simultaneously usable before suspending a corresponding backoff timer. In some embodiments, for example, the first and second component channels are simultaneously usable when they are located in different bands (i.e., a 2.4 GHz band and a 5 GHz band) and/or handled by different RF radios. In some embodiments, the first and second component channels are not simultaneously usable when they are located in adjacent bands (e.g., 5 GHz band and 6 GHz band).

FIG.9is an example timing diagram900for a WLAN communication device configured to simultaneously utilize multiple primary channels, in an embodiment. In an embodiment, the operating channel902corresponds to an operating channel of the AP114, or of a basic service set (BSS) supported by the AP114. In an embodiment, the operating channel902corresponds to an operating channel of a client station154(e.g., the client station154-1). In other embodiments, the operating channel902is employed by a communication device (e.g., an AP or a client station) in a suitable communication network different from the WLAN110. The operating channel902is similar to the operating channel600and includes four component channels Ch0, Ch1, Ch2, and Ch3. Although the component channels are shown as being contiguous, in other embodiments, one or more of the component channels are located in different frequency bands and/or are separated by a frequency gap, as described above.

As described above, in some embodiments, the AP114(or a client station154) is able to simultaneously utilize different primary channels, for example, when the primary channels are located in different bands. In the embodiment shown inFIG.9, the AP114is configured to simultaneously utilize primary channels Ch0 and Ch3. In this embodiment, the AP114does not suspend the backoff timer936that corresponds to the primary channel Ch3 while utilizing the primary channel Ch0 and secondary channel Ch1. In other words, when it is determined that a first component channel and a second component channel are simultaneously usable, the AP114utilizes the second component channel asynchronously with the first component channel. In the embodiment shown inFIG.9, the backoff timer936i) is not suspended during a TXOP910, and ii) expires during the TXOP910, allowing the AP114to perform a transmission952during the TXOP910using a different primary channel Ch3.

FIG.10is a flow diagram illustrating an example method1000for operation of a first communication device in a WLAN communication channel between the first communication device and one or more second communication devices, according to an embodiment. The WLAN communication channel includes a plurality of component channels, for example, component channels as described above and shown inFIGS.4A,4B,5,6A,6B,7,8, and9. In an embodiment, the method1000is implemented by a client station in the WLAN, according to an embodiment. With reference toFIG.1, the method1000is implemented by the network interface162, in an embodiment. For example, in one such embodiment, the PHY processor170is configured to implement the method1000. According to another embodiment, the MAC processor166is also configured to implement at least a part of the method1000. With continued reference toFIG.1, in yet another embodiment, the method1000is implemented by the network interface122(e.g., the PHY processor130and/or the MAC processor126). In other embodiments, the method1000is implemented by other suitable network interfaces.

At block1002, the AP114designates i) a first component channel of the plurality of component channels as a first primary channel, and ii) a second component channel of the plurality of component channels as a second primary channel. In an embodiment, for example, the AP114designates the component channels Ch0 and Ch3 shown inFIG.8as primary channels. In an embodiment, the first component channel and the second component channel are non-contiguous. In an embodiment, for example, the first component channel is separated from the second component channel by at least one third component channel. In another embodiment, the first component channel is located in a different band from the second component channel.

In an embodiment, the WLAN communication channel has i) a first radio frequency (RF) channel segment that occupies a first frequency bandwidth and includes at least the first component channel, ii) a second RF channel segment that occupies a second frequency bandwidth and includes at least the second component channel, and the first frequency bandwidth and the second frequency bandwidth do not overlap and are separated by a frequency gap. In an embodiment, for example, the first RF channel segment and the second RF channel segment correspond to the channel segments410and420as described above with respect toFIGS.4A and4B. In an embodiment, the first communication device includes i) a first RF radio configured for operation in the first RF channel segment and not in the second RF channel segment and ii) a second RF radio configured for operation in the second RF channel segment and not the first RF channel segment. In an embodiment, for example, the first RF radio corresponds to the RF radio328and the second RF radio corresponds to the RF radio336.

At block1004, the AP114suspends a backoff timer that corresponds to the second component channel while utilizing the first component channel and without utilizing the second component channel. In an embodiment, for example, the AP114suspends the backoff timer836without utilizing the component channel Ch3 (FIG.8). In an embodiment, utilization of the first component channel includes at least one of transmitting or receiving media access layer protocol data units (MPDUs). In an embodiment, for example, the utilization includes transmission of the A-MPDU and reception of the block acknowledgment during the TXOP810(FIG.8).

At block1006, the AP114resumes the backoff timer when utilization of the first component channel has completed. In an embodiment, for example, the AP114resumes the backoff timer836after the TXOP810.

FIG.11is a flow diagram illustrating an example method1100for operation of a first communication device in a WLAN communication channel between the first communication device and one or more second communication devices, according to an embodiment. The WLAN communication channel includes a plurality of component channels, for example, component channels as described above and shown inFIGS.4A,4B,5,6A,6B,7,8, and9. In an embodiment, the method1100is implemented by a client station in the WLAN, according to an embodiment. With reference toFIG.1, the method1100is implemented by the network interface162, in an embodiment. For example, in one such embodiment, the PHY processor170is configured to implement the method1100. According to another embodiment, the MAC processor166is also configured to implement at least a part of the method1100. With continued reference toFIG.1, in yet another embodiment, the method1100is implemented by the network interface122(e.g., the PHY processor130and/or the MAC processor126). In other embodiments, the method1100is implemented by other suitable network interfaces.

At block1102, the AP114designates i) a first component channel of the plurality of component channels as a first primary channel, and ii) a second component channel of the plurality of component channels as a second primary channel. In an embodiment, for example, the AP114designates the component channels Ch0 and Ch3 shown inFIG.8as primary channels.

At block1104, the AP114determines whether the first component channel and the second component channel are simultaneously usable by the first communication device. In an embodiment, for example, the AP114determines whether the first component channel and the second component channel are handled by different RF radios.

At block1106, when it is determined that the first component channel and the second component channel are not simultaneously usable by the first communication device, the AP114suspends a backoff timer that corresponds to the second component channel while the first communication device utilizes the first component channel, where utilization of the first component channel includes at least one of transmitting or receiving a media access control protocol data units (MPDUs) via the first component channel. In an embodiment, for example, the AP114suspends the backoff timer836without utilizing the component channel Ch3 (FIG.8). In an embodiment, utilization of the second component channel includes at least one of transmitting or receiving MPDUs via the second component channel.

At block1108, when it is determined that the first component channel and the second component channel are simultaneously usable by the first communication device, the AP114utilizes the second component channel asynchronously with the first component channel.

In an embodiment, the AP114resumes the backoff timer when utilization of the first component channel by the first communication device has completed. In an embodiment, for example, the AP114resumes the backoff timer836after the TXOP810.

FIG.12is a flow diagram illustrating an example method1200for operation of a first communication device in a WLAN communication channel between the first communication device and one or more second communication devices, according to an embodiment. The WLAN communication channel includes a plurality of component channels, for example, component channels as described above and shown inFIGS.4A,4B,5,6A,6B,7,8, and9. In an embodiment, the method1200is implemented by a client station in the WLAN, according to an embodiment. With reference toFIG.1, the method1200is implemented by the network interface162, in an embodiment. For example, in one such embodiment, the PHY processor170is configured to implement the method1200. According to another embodiment, the MAC processor166is also configured to implement at least a part of the method1200. With continued reference toFIG.1, in yet another embodiment, the method1200is implemented by the network interface122(e.g., the PHY processor130and/or the MAC processor126). In other embodiments, the method1200is implemented by other suitable network interfaces.

At block1202, the AP designates i) a first component channel of the plurality of component channels as a primary channel of the WLAN communication channel, and ii) a second component channel of the plurality of component channels as a secondary channel of the WLAN communication channel. In an embodiment, for example, the AP114designates the component channel412(FIG.4) as a primary channel and designates the component channel424-2as a secondary channel. In another embodiment, for example, the AP114designates the component channel Ch0 (FIG.5) as a primary channel512and designates the component channel Ch3 as a secondary channel514-1.

At block1204, the AP114utilizes the first component channel as the primary channel for at least one of transmitting or receiving media access control protocol data units (MPDUs) via the first component channel. In an embodiment, for example, the AP114transmits the PPDU517(FIG.5).

At block1206, the AP114designates i) the first component channel as a secondary channel of the WLAN communication channel, and ii) the second component channel as the primary channel of the WLAN communication channel. In an embodiment, for example, the AP114designates the component channel Ch0 as a secondary channel524and designates the component channel Ch3 as a primary channel522.

At block1208, the AP114utilizes the second component channel as the primary channel for at least one of transmitting or receiving MPDUs via the second component channel. In an embodiment, for example, the AP114transmits the PPDU527(FIG.5).

In an embodiment, the AP114starts a network allocation vector (NAV) synchronization timer after designating the second component channel as the primary channel, and starts a backoff timer after expiration of the NAV synchronization timer, where utilizing the second component channel includes before utilizing the second component channel as the primary channel after expiration of the backoff timer. In an embodiment, the AP114starts the NAV synchronization timer515and starts the backoff timer516, as described above with respect toFIG.5.

In an embodiment, the AP114receives an MPDU that includes a NAV indication via the second component channel during the NAV synchronization timer and i) stops the NAV synchronization timer, and ii) sets a NAV that corresponds to the second component channel using the NAV indication. In an embodiment, for example, the AP114receives the MPDU521, stops the NAV synchronization timer525, and sets the backoff timer526using the NAV indication of the MPDU521, as described above with respect toFIG.5. In an embodiment, the NAV indication is a high efficiency (HE) physical layer (PHY) header that includes a duration field.

In an embodiment, the AP114sets one or more backoff parameters that correspond to the backoff timer to respective values that correspond to a successful frame exchange. In another embodiment, the AP sets one or more backoff parameters that correspond to the backoff timer to respective values that correspond to a service period. In yet another embodiment, the AP114sets one or more backoff parameters that correspond to the backoff timer to respective values that correspond to the first component channel. In an embodiment, for example, the AP114sets the backoff parameters as described above with respect toFIG.7.

In an embodiment, the AP114generates one or more MPDUs that include an explicit indication of the designation of the second component channel as the primary channel. The AP114transmits the one or more MPDUs using at least one of the first component channel and the second component channel.

In an embodiment, the AP114utilizes the first component channel as the primary channel during a first predetermined time period and utilizes the second component channel as the primary channel during a second predetermined time period that does not overlap with the first predetermined time period. In an embodiment, for example, the AP114utilizes the component channel Ch0 as the first primary channel512during the service period510and utilizes the component channel Ch3 as the second primary channel522during the service period520, as described above with respect toFIG.5. In an embodiment, the first predetermined time period corresponds to a first service period and the second predetermined time period corresponds to a second service period.

In an embodiment, the WLAN communication channel has i) a first RF channel segment that occupies a first frequency bandwidth and includes at least the first component channel, ii) a second RF channel segment that occupies a second frequency bandwidth and includes at least the second component channel. The first frequency bandwidth and the second frequency bandwidth do not overlap and are separated by a frequency gap. In an embodiment, for example, the first RF channel segment and the second RF channel segment correspond to the channel segments410and420as described above with respect toFIGS.4A and4B.

At least some of the various blocks, operations, and techniques described above may be implemented utilizing hardware, a processor executing firmware instructions, a processor executing software instructions, or any combination thereof. When implemented utilizing a processor executing software or firmware instructions, the software or firmware instructions may be stored in any computer readable memory such as on a magnetic disk, an optical disk, or other storage medium, in a RAM or ROM or flash memory, processor, hard disk drive, optical disk drive, tape drive, etc. The software or firmware instructions may include machine readable instructions that, when executed by one or more processors, cause the one or more processors to perform various acts.

When implemented in hardware, the hardware may comprise one or more of discrete components, an integrated circuit, an application-specific integrated circuit (ASIC), a programmable logic device (PLD), etc.

While the present invention has been described with reference to specific examples, which are intended to be illustrative only and not to be limiting of the invention, changes, additions and/or deletions may be made to the disclosed embodiments without departing from the scope of the invention.