Padding and backoff operations when transmitting across multiple frequency segments within a WLAN

Abstract

It provides padding and backoff operations for simultaneous transmission across multiple frequency segments within a wireless local area network (WLAN). [Solution] A method for simultaneous transmission within multiple frequency segments in a communication system, wherein the communication device determines that simultaneous transmission and reception across multiple frequency segments within a WLAN is not permitted, transmits a first packet within a first frequency segment starting at a first time, transmits a second packet within a second frequency segment starting at a second time different from the first time, overlapping in time with the transmission of the first packet, and in response to determining that simultaneous transmission and reception across multiple frequency segments is not permitted, includes padding in the first packet such that the end of transmission of the first packet occurs simultaneously with the end of transmission of the second packet.

Description

Technical Field

[0001] [Cross - Reference to Related Applications] This application claims the benefit of U.S. Provisional Patent Application No. 62 / 863,699, filed on Jun. 19, 2019, entitled "Multi - Band Operation: Synchronized and Unsynchronized". The patent application is hereby incorporated by reference in its entirety.

[0002] The present disclosure generally relates to wireless communication systems, and more specifically, to simultaneous transmission and / or reception in multiple frequency segments within a wireless local area network (WLAN).

Background Art

[0003] Wireless Local Area Networks (WLANs) have evolved rapidly over the past 20 years, with advancements in WLAN standards such as the IEEE 802.11 family of standards leading to improved single-user peak data rates. One way to increase data rates is by increasing the frequency bandwidth of the communication channels used in the WLAN. For example, the IEEE 802.11n standard allows the aggregation of two 20MHz subchannels to form a 40MHz aggregated communication channel. In contrast, the more recent IEEE 802.11ax standard allows the aggregation of up to eight 20MHz subchannels to form aggregated communication channels up to 160MHz. Work is now underway on a new version of the IEEE 802.11 standard, known as the IEEE 802.11be standard or Ultra High Throughput (EHT) WLAN. The IEEE 802.11be standard allows the aggregation of as many as 16 20MHz subchannels (or possibly even more) to form aggregated communication channels up to 320MHz (or possibly even wider). Additionally, the IEEE 802.11be standard allows for the aggregation of 20 MHz subchannels in different frequency segments (e.g., separated by a frequency gap) to form separate communication links. Furthermore, the IEEE 802.11be standard may allow for the aggregation of 20 MHz subchannels in different radio frequency (RF) bands to form a single aggregated channel, or may allow for the aggregation of 20 MHz subchannels in different RF bands to form separate communication links.

[0004] The current IEEE 802.11 standard (referred to as "IEEE 802.11 standard" in this specification for brevity) provides a first communication device for transmitting packets to a second communication device over a single communication channel. The IEEE 802.11 standard also provides a mechanism for a device to determine whether a single communication channel is busy or idle, with the aim of determining whether the device can transmit within that single communication channel. [Overview of the Initiative]

[0005] In one embodiment, a method for simultaneous transmission across multiple frequency segments includes the steps of: determining in a communication device that simultaneous transmission and reception across multiple frequency segments are not permitted; transmitting a first packet in a first frequency segment beginning at a first time; transmitting a second packet in a second frequency segment beginning at a second time different from the first time, wherein the transmission of the second packet overlaps in time with the transmission of the first packet; and, in response to the determination that simultaneous transmission and reception across multiple frequency segments are not permitted, including padding in the first packet such that the end of the transmission of the first packet occurs simultaneously with the end of the transmission of the second packet.

[0006] In another embodiment, the first communication device comprises a wireless network interface device configured to communicate over a plurality of frequency segments. The wireless network interface device has one or more integrated circuit (IC) devices configured to determine that simultaneous transmission and reception over the plurality of frequency segments are not permitted; to control the wireless network interface device to transmit a first packet within a first frequency segment beginning at a first time; to control the wireless network interface device to transmit a second packet within a second frequency segment beginning at a second time different from the first time, wherein the transmission of the second packet overlaps in time with the transmission of the first packet; and, in response to the determination that simultaneous transmission and reception over the plurality of frequency segments are not permitted, to include padding in the first packet such that the end of the transmission of the first packet occurs simultaneously with the end of the transmission of the second packet.

[0007] In yet another embodiment, a method for simultaneous transmission within multiple frequency segments comprises the steps of: performing a backoff operation in a communication device corresponding to one of the multiple frequency segments, the backoff operation involving decrementing a backoff counter in relation to the one frequency segment; determining in the communication device whether the backoff counter has expired; and, in response to the determination that the backoff counter has expired, the communication device simultaneously transmits each transmission within each simultaneously starting frequency segment.

[0008] In yet another embodiment, the communication device comprises a wireless network interface device configured to communicate over a plurality of frequency segments. The wireless network interface device includes one or more IC devices and a backoff counter mounted on the one or more IC devices. The one or more IC devices are configured to perform a backoff operation corresponding to one of the plurality of frequency segments, the backoff operation comprising performing a backoff operation, which involves decrementing the backoff counter in relation to the one frequency segment, determining whether the backoff counter has expired, and, in response to the determination that the backoff counter has expired, controlling the wireless network interface device to simultaneously transmit their respective transmissions within each simultaneously starting frequency segment. [Brief explanation of the drawing]

[0009] [Figure 1] This is a block diagram of an exemplary communication system according to one embodiment, in which a communication device wirelessly exchanges information over multiple frequency segments.

[0010] [Figure 2A]This is a diagram illustrating an exemplary communication channel used by the communication system of Figure 1, corresponding to multiple frequency segments, according to one embodiment.

[0011] [Figure 2B] This is a diagram of another exemplary communication channel used by the communication system of Figure 1, corresponding to multiple frequency segments, according to another embodiment.

[0012] [Figure 3] This is a block diagram of an exemplary wireless network interface device configured to communicate over multiple frequency segments, according to one embodiment.

[0013] [Figure 4] This is a diagram illustrating an example of asynchronous transmission within multiple frequency segments according to one embodiment.

[0014] [Figure 5] This is a flowchart illustrating an exemplary method for simultaneous transmission within multiple frequency segments according to one embodiment.

[0015] [Figure 6] This is a flowchart of another exemplary method for simultaneous transmission within multiple frequency segments, according to one embodiment.

[0016] [Figure 7] This figure shows an example of synchronous simultaneous transmission within multiple frequency segments according to one embodiment.

[0017] [Figure 8] This figure illustrates another example of synchronous simultaneous transmission within multiple frequency segments according to a different embodiment.

[0018] [Figure 9] This is a flowchart of another exemplary method for simultaneous transmission within multiple frequency segments, according to one embodiment.

[0019] [Figure 10] FIG. Another example of synchronous simultaneous transmission within a plurality of frequency segments according to another embodiment.

[0020] [Figure 11] FIG. An example of synchronous simultaneous transmission within a plurality of frequency segments according to another embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0021] In a next-generation wireless local area network (WLAN) protocol (e.g., the IEEE 802.11be standard, which may be referred to as the very high throughput (EHT) WLAN standard), aggregation of 16 (or perhaps even more) 20 MHz sub-channels is permitted to form a 320 MHz aggregated communication channel (or perhaps an even wider aggregated communication channel). Additionally, in the IEEE 802.11be standard, aggregation of 20 MHz sub-channels within different frequency segments (e.g., separated by frequency gaps) is permitted to form respective communication links. Additionally, in the IEEE 802.11be standard, formation of a plurality of WLAN communication links corresponding to each frequency segment may be permitted. The plurality of WLAN communication links may be used to simultaneously transmit / receive different information.

[0022] In some embodiments described below, a plurality of packets are simultaneously transmitted within respective frequency segments that start at different times. Padding is included in one or more of the packets so that the transmissions of the plurality of packets end simultaneously.

[0023] In some embodiments described below, each backoff operation is performed in relation to its respective frequency segment to determine when simultaneous transmission may begin across multiple frequency segments. In other embodiments described below, a single backoff operation is performed in relation to only one frequency segment to determine when simultaneous transmission may begin across multiple frequency segments.

[0024] Figure 1 shows an exemplary WLAN 110 according to one embodiment, which uses multiple communication links in multiple frequency segments or different radio frequency (RF) bands. The WLAN 110 includes an access point (AP) 114 having a host processor 118 coupled to a wireless network interface device 122. The wireless network interface device 122 includes one or more media access control (MAC) processors 126 (which may be referred to herein as “MAC processor 126” for brevity) and one or more PHY processors 130 (which may be referred to herein as “PHY processor 130” for brevity). The PHY processor 130 includes a plurality of transceivers 134, which are coupled to a plurality of antennas 138. Although Figure 1 shows three transceivers 134 and three antennas 138, in other embodiments the AP 114 includes a suitable number of other transceivers 134 and antennas 138 (e.g., one, two, four, five, etc.). In some embodiments, the AP114 includes more antennas 138 than the transceiver 134, and antenna switching technology is utilized.

[0025] In one embodiment, the wireless network interface device 122 is configured for operation within a single RF band at a given time. In one embodiment, the wireless network interface device 122 is configured to communicate simultaneously over multiple communication links within each frequency segment of a single RF band, and / or to communicate over multiple communication links at different times. In another embodiment, the wireless network interface device 122 is additionally configured for operation within two or more RF bands simultaneously or at different times. For example, in one embodiment, the wireless network interface device 122 is configured to communicate simultaneously over multiple communication links within each RF band, and / or to communicate over multiple communication links at different times. In one embodiment, the wireless network interface device 122 includes multiple PHY processors 130, each PHY processor 130 corresponding to a respective RF band. In another embodiment, the wireless network interface device 122 includes a single PHY processor 130, in which each transceiver 134 includes a respective RF radio corresponding to a respective RF band.

[0026] The wireless network interface device 122 is implemented using one or more integrated circuits (ICs) configured to operate as described below. For example, the MAC processor 126 may be at least partially implemented on a first IC, and the PHY processor 130 may be at least partially implemented on a second IC. For example, in various embodiments, the first IC and the second IC may be packaged together in a single IC package to form a modular device, or they may be coupled together on a single printed circuit board. As another example, at least a portion of the MAC processor 126 and at least a portion of the PHY processor 130 may be implemented on a single IC. For example, the wireless network interface device 122 may be implemented using a system-on-a-chip (SoC). The SoC includes at least a portion of the MAC processor 126 and at least a portion of the PHY processor 130.

[0027] In one embodiment, the host processor 118 includes a processor configured to execute machine-readable instructions stored in a memory device (not shown), such as random access memory (RAM), read-only memory (ROM), or flash memory. In one embodiment, the host processor 118 may be at least partially mounted on a first IC, and the network device 122 may be at least partially mounted on a second IC. As another example, the host processor 118 and at least a portion of the wireless network interface device 122 may be mounted on a single IC.

[0028] In various embodiments, the MAC processor 126 and / or PHY processor 130 of the AP114 are configured to generate and process data units compliant with a WLAN communication protocol, such as a communication protocol compliant with the IEEE 802.11 standard or another suitable wireless communication protocol. For example, the MAC processor 126 may be configured to implement MAC layer functions, including MAC layer functions of a WLAN communication protocol, and the PHY processor 130 may be configured to implement PHY functions, including PHY functions of a WLAN communication protocol. For example, the MAC processor 126 is configured to generate MAC layer data units, such as MAC Service Data Units (MSDUs) and MAC Protocol Data Units (MPDUs), and to provide the MAC layer data units to the PHY processor 130. Additionally, in some embodiments, the MAC processor 126 is configured to select a communication link on which the MAC layer data units should be transmitted and to control the PHY processor 130 so that the MAC layer data units are transmitted within the selected communication link. In addition, in some embodiments, the MAC processor 126 is configured to determine when each communication link is idle and available for transmission and to control the PHY processor 130 so that MAC layer data units are transmitted when each communication link is idle. Furthermore, in some embodiments, the MAC processor 126 is configured to determine when a client station is in sleep mode and therefore unavailable for transmission or reception. For example, according to some embodiments, the MAC processor 126 is configured to negotiate a schedule with the client station regarding when it is permitted to go into sleep mode and when it should wake up and become available for transmission or reception to and from AP 114.

[0029] The PHY processor 130 may be configured to receive MAC layer data units from the MAC processor 126, encapsulate the MAC layer data units, and generate PHY data units such as PHY protocol data units (PPDUs) for transmission over the antenna 138. Similarly, the PHY processor 130 may be configured to receive PHY data units received over the antenna 138 and extract the MAC layer data units encapsulated within the PHY data units. The PHY processor 130 may provide the extracted MAC layer data units to the MAC processor 126, which then processes the MAC layer data units.

[0030] PHY data units may be referred to as “packets” in this specification, and MAC layer data units may be referred to as “frames” in this specification.

[0031] According to one embodiment, in connection with the generation of one or more RF signals for transmission, the PHY processor 130 is configured to process data corresponding to the PPDU (which may include modulation, filtering, etc.) to generate one or more digital baseband signals and to convert the digital baseband signals into one or more analog baseband signals. Additionally, the PHY processor 130 is configured to upconvert one or more analog baseband signals into one or more RF signals for transmission via one or more antennas 138.

[0032] In connection with the reception of one or more RF signals, the PHY processor 130 is configured to down-convert one or more RF signals into one or more analog baseband signals, and to convert one or more analog baseband signals into one or more digital baseband signals. The PHY processor 130 is further configured to process (including demodulation, filtering, etc.) one or more digital baseband signals to generate a PPDU.

[0033] In various embodiments, the PHY processor 130 includes an amplifier (e.g., a low-noise amplifier (LNA), a power amplifier, etc.), an 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) computers (e.g., fast Fourier transform (FFT) computers), one or more discrete inverse Fourier transform (IDFT) computers (e.g., inverse fast Fourier transform (IFFT) computers), one or more modulators, one or more demodulators, etc.

[0034] The PHY processor 130 is configured to generate one or more RF signals that are supplied to one or more antennas 138. The PHY processor 130 is also configured to receive one or more RF signals from one or more antennas 138.

[0035] According to some embodiments, the MAC processor 126 is configured to control the PHY processor 130 to generate one or more RF signals, for example, by providing the PHY processor 130 with one or more MAC layer data units (e.g., MPDUs) and by optionally providing the PHY processor 130 with one or more control signals. In one embodiment, the MAC processor 126 includes a processor configured to execute machine-readable instructions stored in a memory device (not shown), such as RAM, ROM, or flash memory. In other embodiments, the MAC processor 126 additionally or alternatively includes one or more hardware state machines.

[0036] According to some embodiments, the MAC processor 126 includes or implements a backoff controller 140 configured to implement a backoff procedure in relation to determining when transmission in a communication channel can proceed. The backoff controller 140 includes one or more backoff counters (sometimes referred to as timers) 142. When the network interface device 122 is transmitting and determines that the transmission of a data unit has failed and should be retransmitted, the backoff controller 140 invokes a backoff procedure. The backoff procedure generally involves setting the backoff counters 142 and decrementing the backoff counters 142 to determine when the network interface device 122 can transmit a frame.

[0037] In some embodiments, the backoff counter 142 is set to a randomly or pseudo-randomly selected value such that the backoff counters of different communication devices in the network tend to reach zero at different times. The backoff controller 140 controls the decrementing of the backoff counter 142 when it determines that the channel medium is idle. On the other hand, if the backoff controller 140 determines that the communication medium is busy, it pauses the decrementing of the backoff counter 142 and does not resume until it is later determined that the communication medium is idle. Generally, when the backoff counter 142 reaches zero, the backoff controller 140 determines that the communication device is free to transmit. In some embodiments, before transmission, the network interface device 122 also determines whether the subchannel on which the transmission will take place has been idle for a defined period immediately preceding the start of the transmission. In some embodiments, if the backoff counter 142 has reached zero but the subchannel on which the transmission will take place has not been idle for a defined period immediately preceding the start of the transmission, the transmission does not take place and the backoff counter is reset.

[0038] In one embodiment, determining whether a channel medium is idle involves measuring the energy level within the channel medium and comparing the measured energy level to a threshold. According to one embodiment, if the measured energy level is less than the threshold, the channel medium is determined to be idle; conversely, if the measured energy level meets the threshold (e.g., greater than the threshold, greater than or equal to the threshold, etc.), the channel medium is determined to be busy. In some embodiments, the PHY processor 130 includes one or more energy sensors (not shown) that measure the energy level within one or more frequency segments of the communication channel, and the measured energy level is used to determine whether the channel medium is idle.

[0039] In one embodiment, setting the backoff counter 142 involves randomly or pseudo-randomly selecting an initial value for the backoff counter 142 from a range of multiple initial values. In one embodiment, the range of initial values ​​is [0, CW], where CW is the contention window parameter, and both the initial value and CW are units of slots, each slot corresponding to an appropriate period. For example, the IEEE 802.11 standard defines slot times of 20 microseconds (IEEE 802.11b) and 9 microseconds (IEEE 802.11a, 11n, and 11ac), and different slot times are used for different versions of the protocol. In one embodiment, CW is initially set to the minimum value CWmin. However, after each attempted transmission fails (e.g., failure to receive an acknowledgment of transmission), the value of CW is approximately doubled, up to the upper limit CWmax. The parameters CWmin and CWmax are also units of slots. In one embodiment, the backoff counter 142 is decremented in units of slots.

[0040] In some embodiments, and in at least some scenarios, if the communication channel includes multiple frequency segments, a plurality of separate backoff counters 142 are maintained for each of the multiple frequency segments. In some embodiments, and in at least some scenarios, if the communication channel includes multiple frequency segments, a single backoff counter 142 is maintained for one of the multiple frequency segments.

[0041] In various embodiments, the backoff controller 140 performs one or more of the following operations related to one or more backoff counters 142, which are described in more detail below: i) determining whether to use multiple backoff counters 142 corresponding to each frequency segment when transmitting simultaneously over multiple frequency segments; ii) selecting one frequency segment to which a single backoff counter 142 corresponds when a single backoff counter 142 is used when transmitting simultaneously over multiple frequency segments (or does not perform any of these).

[0042] In one embodiment, the backoff controller 140 is implemented by a processor that executes machine-readable instructions stored in memory, which cause the processor to perform operations described in more detail below. In another embodiment, the backoff controller 140 additionally or alternatively includes hardware circuitry (e.g., one or more counters, one or more timers, one or more hardware state machines, etc.) configured to perform operations described in more detail below. In some embodiments, where the hardware circuitry includes one or more hardware state machines, one or more hardware state machines are configured to perform operations described in more detail below.

[0043] Additionally or alternatively, according to one embodiment, the MAC processor 126 includes or implements a synchronous transmission controller 146 configured to determine when multiple transmissions within each of a plurality of frequency segments are synchronized (e.g., multiple transmissions start simultaneously and optionally end simultaneously). In some embodiments, when multiple transmissions are transmitted simultaneously across multiple frequency segments, multiple backoff counters 142 corresponding to each frequency segment are used, the synchronous transmission controller 146 postpones transmissions in all of the multiple frequency segments until all of the multiple backoff counters 142 have expired (e.g., reached zero). In some embodiments, when simultaneous transmissions across multiple frequency segments are asynchronous (e.g., each transmission within each frequency segment starts at a different time), the synchronous transmission controller 146 is configured to control the PHY processor 130 so that each transmission within each frequency segment ends simultaneously.

[0044] In one embodiment, the synchronous transmission controller 146 is implemented by a processor that executes machine-readable instructions stored in memory, which cause the processor to perform operations described in more detail below. In another embodiment, the synchronous transmission controller 146 includes additional or alternative hardware circuitry configured to perform operations described in more detail below. In some embodiments, the hardware circuitry includes one or more hardware state machines configured to perform operations described in more detail below.

[0045] In other embodiments, the backoff controller 140 and / or the synchronous transmission controller 146 are omitted from AP114.

[0046] Furthermore, the WLAN 110 includes a plurality of client stations 154. Although three client stations 154 are shown in Figure 1, in various embodiments, the WLAN 110 includes any other appropriate number of client stations 154 (e.g., one, two, four, five, six, etc.). Client station 154-1 includes a host processor 158 coupled to a wireless network interface device 162. The wireless network interface device 162 includes one or more MAC processors 166 (which may be referred to herein as "MAC processor 166" for brevity) and one or more PHY processors 170 (which may be referred to herein as "PHY processor 170" for brevity). The PHY processor 170 includes a plurality of transceivers 174, which are coupled to a plurality of antennas 178. Figure 1 shows three transceivers 174 and three antennas 178, but in other embodiments, the client station 154-1 includes other appropriate numbers (e.g., one, two, four, five, etc.) of transceivers 174 and antennas 178. In some embodiments, the client station 154-1 includes more antennas 178 than transceivers 174, and antenna switching technology is utilized.

[0047] In one embodiment, the wireless network interface device 162 is configured for operation within a single RF band at a given time. In another embodiment, the wireless network interface device 162 is configured for operation within two or more RF bands simultaneously or at different times. For example, in one embodiment, the wireless network interface device 162 includes a plurality of PHY processors 170, each PHY processor 170 corresponding to a respective RF band. In another embodiment, the wireless network interface device 162 includes a single PHY processor 170, in which each transceiver 174 includes a respective RF radio corresponding to a respective RF band. In one embodiment, the wireless network interface device 162 includes a plurality of MAC processors 166, each MAC processor 166 corresponding to a respective RF band. In another embodiment, the wireless network interface device 162 includes a single MAC processor 166 corresponding to a plurality of RF bands.

[0048] The wireless network interface device 162 is implemented using one or more ICs configured to operate as described below. For example, the MAC processor 166 may be implemented on at least a first IC, and the PHY processor 170 may be implemented on at least a second IC. For example, in various embodiments, the first IC and the second IC may be packaged together in a single IC package to form a modular device, or they may be coupled together on a single printed circuit board. As another example, at least a portion of the MAC processor 166 and at least a portion of the PHY processor 170 may be implemented on a single IC. For example, the wireless network interface device 162 may be implemented using an SoC, which includes at least a portion of the MAC processor 166 and at least a portion of the PHY processor 170.

[0049] In one embodiment, the host processor 158 includes a processor configured to execute machine-readable instructions stored in a memory device (not shown), such as RAM, ROM, or flash memory. In one embodiment, the host processor 158 may be at least partially mounted on a first IC, and the network device 162 may be at least partially mounted on a second IC. As another example, the host processor 158 and at least a portion of the wireless network interface device 162 may be mounted on a single IC.

[0050] In various embodiments, the MAC processor 166 and PHY processor 170 of the client station 154-1 are configured to generate data units compliant with the WLAN communication protocol or another suitable communication protocol and to process the received data units. For example, the MAC processor 166 may be configured to implement MAC layer functions, including the MAC layer functions of the WLAN communication protocol, and the PHY processor 170 may be configured to implement PHY functions, including the PHY functions of the WLAN communication protocol. The MAC processor 166 may be configured to generate MAC layer data units, such as MSDUs and MPDUs, and to provide the MAC layer data units to the PHY processor 170. Additionally, in some embodiments, the MAC processor 166 is configured to select a communication link on which the MAC layer data units should be transmitted and to control the PHY processor 170 so that the MAC layer data units are transmitted within the selected communication link. Also in some embodiments, the MAC processor 166 is configured to determine when each communication link is idle and available for transmission and to control the PHY processor 170 so that the MAC layer data units are transmitted when each communication link is idle. Additionally, in some embodiments, the MAC processor 166 is configured to control when each part of the wireless network interface device 162 is in a sleep or wake state, for example, to conserve power. For example, according to some embodiments, the MAC processor 166 is configured to negotiate a schedule with AP114 regarding when client station 154-1 is allowed to go into sleep mode and when client station 154-1 should be woken up and available for transmission or reception to and from AP114.

[0051] The PHY processor 170 may be configured to receive MAC layer data units from the MAC processor 166, encapsulate the MAC layer data units, and generate PHY data units such as PPDUs for transmission over the antenna 178. Similarly, the PHY processor 170 may be configured to receive PHY data units received over the antenna 178 and extract the MAC layer data units encapsulated within the PHY data units. The PHY processor 170 may provide the extracted MAC layer data units to the MAC processor 166, which then processes the MAC layer data units.

[0052] According to one embodiment, the PHY processor 170 is configured to down-convert one or more RF signals received via one or more antennas 178 into one or more baseband analog signals, and to convert the analog baseband signals into one or more digital baseband signals. The PHY processor 170 is further configured to process one or more digital baseband signals to demodulate one or more digital baseband signals and generate a PPDU. The PHY processor 170 includes an amplifier (e.g., LNA, power amplifier, etc.), an RF down-converter, an RF up-converter, a plurality of filters, one or more ADCs, one or more DACs, one or more DFT computers (e.g., FFT computers), one or more IDFT computers (e.g., IFFT computers), one or more modulators, one or more demodulators, etc.

[0053] The PHY processor 170 is configured to generate one or more RF signals that are supplied to one or more antennas 178. The PHY processor 170 is also configured to receive one or more RF signals from one or more antennas 178.

[0054] According to some embodiments, the MAC processor 166 is configured to control the PHY processor 170 to generate one or more RF signals, for example, by providing the PHY processor 170 with one or more MAC layer data units (e.g., MPDUs) and by optionally providing the PHY processor 170 with one or more control signals. In one embodiment, the MAC processor 166 includes a processor configured to execute machine-readable instructions stored in a memory device (not shown), such as RAM, ROM, or flash memory. In one embodiment, the MAC processor 166 includes a hardware state machine.

[0055] According to some embodiments, the MAC processor 166 includes or implements a backoff controller 190 that is the same as or similar to the backoff controller 140. The backoff controller 190 includes one or more backoff counters (sometimes referred to as timers) 192. The backoff controller 190 controls the decrementing of the backoff counters 192 when it determines that the channel medium is idle. On the other hand, if the backoff controller 190 determines that the communication medium is busy, it pauses the decrementing of the backoff counters 192 and does not resume decrementing the backoff counters 192 until it is later determined that the communication medium is idle. Generally, when the backoff counters 192 reach zero while the communication medium is still idle, the backoff controller 190 determines that the communication device is free to transmit. On the other hand, when the backoff counters 192 reach zero while the communication medium is busy, the backoff controller 190 resets the backoff counters 192 and the process is repeated.

[0056] In some embodiments, and in at least some scenarios, if the communication channel includes multiple frequency segments, a plurality of separate backoff counters 192 are maintained for each of the multiple frequency segments. In some embodiments, and in at least some scenarios, if the communication channel includes multiple frequency segments, a single backoff counter 192 is maintained for one of the multiple frequency segments.

[0057] In various embodiments, the backoff controller 190 performs one or more of the following operations related to the operation of one or more backoff counters 192, which are described in more detail below: i) determining whether to use multiple backoff counters 192 corresponding to each frequency segment when transmitting simultaneously over multiple frequency segments; ii) selecting one frequency segment to which a single backoff counter 192 corresponds when a single backoff counter 192 is used when transmitting simultaneously over multiple frequency segments (or not performing any of these).

[0058] In one embodiment, the backoff controller 190 is implemented by a processor that executes machine-readable instructions stored in memory, which cause the processor to perform operations described in more detail below. In another embodiment, the backoff controller 190 additionally or alternatively includes hardware circuitry (e.g., one or more counters, one or more timers, one or more hardware state machines, etc.) configured to perform operations described in more detail below. In some embodiments, where the hardware circuitry includes one or more hardware state machines, one or more hardware state machines are configured to perform operations described in more detail below.

[0059] In addition or alternatively, according to some embodiments, the MAC processor 166 includes or implements a synchronous transmission controller 196 that is the same as or similar to the synchronous transmission controller 146. According to one embodiment, the synchronous transmission controller 196 is configured to determine when multiple transmissions within each of a plurality of frequency segments are synchronized (e.g., multiple transmissions start simultaneously and optionally end simultaneously). In some embodiments, when multiple transmissions are transmitted simultaneously across multiple frequency segments, multiple backoff counters 192 corresponding to each frequency segment are used, the synchronous transmission controller 196 postpones transmissions in all of the multiple frequency segments until all of the multiple backoff counters 192 have expired (e.g., reached zero). In some embodiments, when simultaneous transmissions across multiple frequency segments are asynchronous (e.g., each transmission within each frequency segment starts at a different time), the synchronous transmission controller 196 is configured to control the PHY processor 170 so that each transmission within each frequency segment ends simultaneously.

[0060] In one embodiment, the synchronous transmission controller 196 is implemented by a processor that executes machine-readable instructions stored in memory, which cause the processor to perform operations described in more detail below. In another embodiment, the synchronous transmission controller 196 includes additional or alternative hardware circuitry configured to perform operations described in more detail below. In some embodiments, the hardware circuitry includes one or more hardware state machines configured to perform operations described in more detail below.

[0061] In one embodiment, each of client stations 154-2 and 154-3 has the same or similar structure as client station 154-1. In one embodiment, one or more of client stations 154-2 and 154-3 have a suitable structure different from client station 154-1. Each of client stations 154-2 and 154-3 has the same or different number of transceivers and antennas. For example, according to one embodiment, each of client stations 154-2 and / or client station 154-3 has only two transceivers and two antennas (not shown).

[0062] Figure 2A is a diagram of an exemplary operating channel 200 used in the communication system 110 of Figure 1 according to one embodiment. The operating channel 200 includes a plurality of subchannels 204 in a first frequency segment 208 and a plurality of subchannels 212 in a second frequency segment 216. The operating channel 200 extends across the entire bandwidth 220. In one embodiment, the first frequency segment 208 and the second frequency segment 216 are in the same radio frequency (RF) band.

[0063] In other embodiments, the first frequency segment 208 and the second frequency segment 216 are in different RF bands. The Federal Communications Commission (FCC) currently permits wireless local area networks (WLANs) to operate in multiple RF bands, for example, the 2.4 GHz band (approximately 2.4 GHz to 2.5 GHz) and the 5 GHz band (approximately 5.170 GHz to 5.835 GHz). Recently, the FCC proposed that WLANs also operate in the 6 GHz band (5.925 GHz to 7.125 GHz). Regulators in other countries / regions also permit WLAN operations in the 2.4 GHz and 5 GHz bands and consider them to permit WLAN operations in the 6 GHz band. Future WLAN protocols currently under development may permit multiband operation, where WLANs can use spectrum in multiple RF bands simultaneously.

[0064] In some embodiments, the first frequency segment 208 is used as a first communication link, the second frequency segment 216 is used as a second communication link, and the first and second communication links are used for simultaneous transmission.

[0065] In one embodiment, each of the subchannels 204 / 212 extends to 20 MHz. Thus, as shown in Figure 2A, the first frequency segment 208 extends to 160 MHz and the second frequency segment 216 extends to 80 MHz. In another embodiment, the first frequency segment 208 includes another suitable number (e.g., one, two, four, etc.) of subchannels 204, extending to another suitable bandwidth, e.g., 20 MHz, 40 MHz, 80 MHz, etc., and / or the second frequency segment 216 includes another suitable number (e.g., one, two, eight, etc.) of subchannels 212, extending to another suitable bandwidth, e.g., 20 MHz, 40 MHz, 160 MHz, etc.

[0066] In the first frequency segment 208, one subchannel 204-1 is designated as the primary subchannel, and the other subchannels 204 / 212 are designated as secondary subchannels. According to some embodiments, control frames and / or management frames are transmitted within the primary subchannel 204-1. According to some embodiments, in some embodiments, the primary subchannel must be idle so that either subchannel 204 / 212 can be used for transmission. In some embodiments, subchannel 212 in the second frequency segment 216 is also designated as the primary subchannel (not shown). In some embodiments where the second frequency segment 216 also includes the primary subchannel, in at least some scenarios, control frames and / or management frames are additionally or alternatively transmitted within the primary subchannel of the second frequency segment 216. In other embodiments, control frames and / or management frames are transmitted only within the primary subchannel 204-1 of the first frequency segment 208.

[0067] According to some embodiments, in some embodiments where the second frequency segment 216 also includes a primary subchannel, the primary subchannel 204-1 of the first frequency segment 208 must be idle so that any of the subchannels 204 can be used for transmission, and the primary subchannel of the second frequency segment 216 must be idle so that any of the subchannels 212 can be used for transmission. According to some embodiments, in other embodiments, even if the primary subchannel 204-1 is not idle, one or more of the secondary subchannels 204 can be used for transmission, and / or even if the primary subchannel of the second frequency segment 216 is not idle, one or more of the secondary subchannels 212 can be used for transmission.

[0068] In other embodiments, subchannel 212 within the second frequency segment 216 is not designated as the primary subchannel.

[0069] In one embodiment, the backoff counters 142 / 192 (Figure 1) correspond to the primary subchannels of the operating channel 200. For example, when the primary subchannel is idle, the backoff counters 142 / 192 are decremented, and when the primary subchannel is busy, the backoff counters 142 / 192 are paused. In one embodiment, each backoff counter 142 / 192 (Figure 1) corresponds to each primary subchannel of the operating channel 200. For example, when each primary subchannel is idle, each backoff counter 142 / 192 is decremented, and when each primary subchannel is busy, each backoff counter 142 / 192 is paused.

[0070] Figure 2B is a diagram of another exemplary operating channel 250 used in the communication system 110 of Figure 1, according to a different embodiment. Operating channel 250 is similar to exemplary operating channel 200 in Figure 2A, and elements of the same number are not described in detail for brevity. In exemplary operating channel 250, the first frequency segment 208 and the second frequency segment 216 are separated by a frequency gap 254. In some embodiments, the first frequency segment 208 and the second frequency segment 216 are in the same RF band. In other embodiments, the first frequency segment 208 and the second frequency segment 216 are in different RF bands.

[0071] In one embodiment, the backoff counters 142 / 192 (Figure 1) correspond to the primary subchannels of the operating channel 250. For example, when the primary subchannel is idle, the backoff counters 142 / 192 are decremented, and when the primary subchannel is busy, the backoff counters 142 / 192 are paused. In one embodiment, each backoff counter 142 / 192 (Figure 1) corresponds to each primary subchannel of the operating channel 250. For example, when each primary subchannel is idle, each backoff counter 142 / 192 is decremented, and when each primary subchannel is busy, each backoff counter 142 / 192 is paused.

[0072] Referring now to Figures 2A and 2B, according to some embodiments, one or more of the subchannels 204 / 212 are "punctured" (not shown in Figures 2A and 2B), and for example, nothing is transmitted within the "punctured" subchannel.

[0073] While the exemplary operating channels 200 and 250 in Figures 2A and 2B are shown to include two frequency segments 208 / 216, other suitable operating channels may include three or more frequency segments (e.g., including a third frequency segment, including a third frequency segment and a fourth frequency segment, etc.). In some embodiments, the third frequency segment is separated from the second frequency segment 216 by a frequency gap, within which nothing is transmitted, similar to gap 254. In some embodiments, the third frequency segment is frequency-contiguous with the second frequency segment 216.

[0074] In some embodiments, each frequency segment, as shown in Figures 2A and 2B, is associated with a different MAC address. For example, in embodiments where each frequency segment is used as a communication link, each communication link corresponds to a different MAC address.

[0075] Figure 3 shows an exemplary network interface device 300 configured for simultaneous communication over multiple communication links within each frequency segment, according to one embodiment. Network interface device 300 is one embodiment of network interface device 122 of AP114 in Figure 1. Network interface device 300 is one embodiment of network interface device 162 of client station 154-1 in Figure 1. In other embodiments, network interface device 122 and / or network interface device 162 have appropriate structures different from network interface device 300. Additionally, in some embodiments, network interface device 300 is used in appropriate communication devices other than the communication devices in Figure 1, and / or in appropriate wireless networks other than the wireless network in Figure 1.

[0076] In the illustrated embodiment, the network interface device 300 is configured for simultaneous communication via a first communication link in a first frequency segment and a second communication link in a second frequency segment.

[0077] The network interface device 300 includes a MAC processor 304 coupled to the PHY processor 308. The MAC processor 304 exchanges frames (or PSDUs) with the PHY processor 308.

[0078] In one embodiment, MAC processor 304 corresponds to MAC processor 126 in Figure 1. In another embodiment, MAC processor 304 corresponds to MAC processor 166 in Figure 1. In one embodiment, PHY processor 308 corresponds to one or more PHY processors 130 in Figure 1. In another embodiment, PHY processor 308 corresponds to one or more PHY processors 170 in Figure 1.

[0079] The MAC processor 304 includes common MAC logic 312 and link-specific (LS) MAC logic 316. The common MAC logic 312 generally implements MAC layer functions common to multiple communication links. For example, the common MAC logic 312 is configured to respond to the reception of data to be transferred to another communication device in the WLAN (e.g., from a host processor (not shown), from a wired communication link (not shown), etc.) by encapsulating the data into MAC layer data units such as MSDU, MPDU, aggregated MPDU (A-MPDU) for transmission over multiple communication links, and to decapsulate the data from the MSDU, MPDU, A-MPDU, etc. received over the multiple communication links. Additionally, in some embodiments, the common MAC logic 312 is configured to select the communication link to which the MAC layer data units should be transmitted.

[0080] Each LS MAC logic 316 generally implements MAC layer functionality specific to the particular communication link to which it corresponds. For example, in some embodiments, LS MAC logic 316a is configured to determine when a first communication link is idle and available for transmission, and LS MAC logic 316b is configured to determine when a second communication link is idle and available for transmission. In some embodiments, each LS MAC logic 316 is associated with a respective network address (e.g., MAC address), i.e., LS MAC logic 316a is associated with a first network address (e.g., a first MAC address), and LS MAC logic 316a is associated with a second network address (e.g., a second MAC address) different from the first network address.

[0081] In some embodiments, the common MAC logic 312 implements the backoff controllers 140 / 190 described above with reference to Figure 1. In some embodiments, the common MAC logic 312 additionally or alternatively implements the synchronous transmission controller 196 described above with reference to Figure 1. In some embodiments, some or all of the backoff controllers 140 / 190 are implemented as respective link-specific backoff controllers 140 / 190 within each LS MAC logic 316.

[0082] PHY processor 308a includes a baseband signal processor 320a corresponding to a first communication link, and PHY processor 308b includes a baseband signal processor 320b corresponding to a second communication link. PHY processor 308a also includes a first RF radio (radio-1) 328a corresponding to the first communication link, and PHY processor 308b includes a second RF radio (radio-2) 328b corresponding to the second communication link. Baseband signal processor 320a is coupled to the first RF radio 328a, and baseband signal processor 320b is coupled to the second RF radio 328b. In one embodiment, RF radios 328a and 328b correspond to transceiver 134 in Figure 1. In another embodiment, RF radios 328a and 328b correspond to transceiver 174 in Figure 1. In one embodiment, RF radio 328a is configured to operate in a first RF band, and RF radio 328b is configured to operate in a second RF band. In another embodiment, both RF radios 328a and 328b are configured to operate in the same RF band.

[0083] In one embodiment, the baseband signal processor 320 is configured to receive frames (or PSDUs) from the MAC processor 304, encapsulate the frames (or PSDUs) into individual packets, and generate the respective baseband signals corresponding to each packet.

[0084] The baseband signal processor 320a provides each baseband signal generated by the baseband signal processor 320a to radio-1 328a. The baseband signal processor 320b provides each baseband signal generated by the baseband signal processor 320b to radio-2 328b. Radio-1 328a and radio-2 328b each upconvert their respective baseband signals for transmission over the first and second communication links to generate their respective RF signals. Radio-1 328a transmits the first RF signal over the first frequency segment, and radio-2328b transmits the second RF signal over the second frequency segment.

[0085] Furthermore, radio-1 328a and radio-2328b are configured to receive their respective RF signals via a first and second communication link, respectively. Radio-1 328a and radio-2328b generate their respective baseband signals corresponding to their respective received signals. The generated baseband signals are provided to their respective baseband signal processors 320a and 320b. The respective baseband signal processors 320a and 320b generate their respective PSDUs corresponding to their respective received signals and provide their respective PSDUs to the MAC processor 304. In one embodiment, the MAC processor 304 processes the PSDUs received from the baseband signal processors 320a and 320b.

[0086] In some embodiments, the common MAC logic 312 and / or LS MAC logic 316 are implemented at least partially by a processor configured to execute machine-readable instructions stored in a memory device (not shown), such as RAM, ROM, or flash memory. In other embodiments, the common MAC logic 312 and / or LS MAC logic 316 are additionally or alternatively implemented by hardware logic, such as one or more hardware state machines.

[0087] In some embodiments, the baseband signal processor 320 is implemented at least partially by a processor configured to execute machine-readable instructions stored in a memory device (not shown), such as RAM, ROM, or flash memory. In other embodiments, the baseband signal processor 320 is additionally or alternatively implemented by hardware logic, such as one or more hardware state machines, hardware computers (e.g., FFT computers, IFFT computers), or hardware modulators.

[0088] While the exemplary network interface 300 shown in Figure 3 includes a single MAC processor 304, in some embodiments other suitable network interface devices include multiple MAC processors, each of which corresponds to each communication link. While the exemplary network interface 300 shown in Figure 3 includes multiple PHY processors 308, in some embodiments other suitable network interface devices include a single PHY processor, with each of the multiple RF radios corresponding to each communication link. In some embodiments, the single PHY processor includes multiple baseband processors 320, but in other embodiments, the single PHY processor includes a single baseband processor configured to generate multiple baseband signals corresponding to each communication link and to process multiple baseband signals received from multiple RF radios.

[0089] In some wireless networks, one or more communication devices within the wireless network may not be able to transmit and receive simultaneously over different frequency segments due to, for example, physical limitations of the communication devices or channel conditions. Additionally or alternatively, AP114 may determine that simultaneous transmission and reception over different frequency segments is not permitted within the WLAN due to, for example, physical limitations of one or more communication devices within the WLAN or channel conditions.

[0090] In one embodiment, client station 154 notifies AP114 whether client station 154 can transmit and receive simultaneously across different frequency segments. For example, in one embodiment, during the setup phase of an operating channel having multiple frequency links (sometimes referred to as a "multilink association"), client station 154 transmits frames (e.g., management frames, control frames, action frames, etc.) to AP114 that contain information indicating whether client station 154 can transmit and receive simultaneously. As another example, in one embodiment, when joining or attempting to join a WLAN managed by multiple frequency links (sometimes referred to as a "multilink association"), client station 154 transmits frames (e.g., association request frames, re-association request frames, probe request frames, etc.) to AP114 that contain information indicating whether client station 154 can transmit and receive simultaneously.

[0091] According to one embodiment, AP114 notifies one or more client stations 154 whether simultaneous transmission and reception over different frequency segments is permitted within WLAN110. For example, according to one embodiment, during the setup phase of an operating channel having multiple frequency links (sometimes referred to as a "multilink association"), AP114 transmits frames (e.g., management frames, control frames, action frames, etc.) to one or more client stations 154 that contain information indicating whether simultaneous transmission and reception over different frequency segments is permitted within WLAN110. As another example, according to one embodiment, when a client station 154 attempts to join WLAN110 managed by multiple frequency links (sometimes referred to as a "multilink association"), AP114 transmits frames (e.g., association response frames, re-association response frames, probe response frames, etc.) to the client station 154 that contain information indicating whether simultaneous transmission and reception over different frequency segments is permitted within WLAN110. As another example, according to one embodiment, AP114 periodically transmits a beacon frame containing information indicating whether simultaneous transmission and reception over different frequency segments is permitted within WLAN110. As another example, according to one embodiment, if AP114 decides to switch from allowing simultaneous transmission and reception over different frequency segments to not allowing simultaneous transmission and reception over different frequency segments (or vice versa), AP114 transmits a frame (e.g., management frame, control frame, action frame, etc.) containing information indicating whether simultaneous transmission and reception over different frequency segments is permitted within WLAN110.

[0092] In some embodiments, simultaneous transmission / reception across multiple frequency segments is not permitted (e.g., i) the first communication device does not permit simultaneous transmission / reception across multiple frequency segments, ii) the second communication device does not permit simultaneous transmission / reception across multiple frequency segments, iii) simultaneous transmission / reception across multiple frequency segments is not permitted within the WLAN, etc.), and the first communication device is transmitting asynchronous transmissions across multiple frequency segments (e.g., multiple transmissions across multiple frequency segments do not start simultaneously), then the first communication device simultaneously terminates the asynchronous transmissions across multiple frequency segments. In some embodiments, if one or more of the asynchronous transmissions across multiple frequency segments prompt another communication device to transmit an acknowledgment, simultaneously terminating the asynchronous transmissions helps prevent one communication device from transmitting within one frequency segment at the same time that another communication device transmits an acknowledgment within another frequency segment.

[0093] Figure 4 shows an example of asynchronous transmission 400 in multiple frequency segments corresponding to multiple communication links according to one embodiment. The first communication device transmits a first packet 404 in a first frequency segment corresponding to a first communication link and simultaneously transmits a second packet 408 in a second frequency segment corresponding to a second communication link. The transmission of the first packet 404 begins before the transmission of the second packet 408 begins. Therefore, the transmission of the first packet 404 and the transmission of the second packet 408 begin at different times.

[0094] The first communication device receives a first acknowledgment 412 (e.g., an acknowledgment frame included in the packet, a block acknowledgment (BA) frame, etc.) within a first frequency segment responding to the first packet 404. In one embodiment, the communication device receiving the packet 404 begins transmitting the first acknowledgment 412 for a defined period after it has finished receiving the packet 404. In one embodiment, the defined period is a short interframe space (SIFS) as defined by the IEEE 802.11 standard. In other embodiments, the defined period is another appropriate duration.

[0095] Similarly, the first communication device receives a second acknowledgment 416 (e.g., an acknowledgment frame, BA frame, etc., contained in the packet) within a second frequency segment in response to the second packet 408. In one embodiment, the communication device receiving the second packet 408 begins transmitting the second acknowledgment 416 for a defined period after it has finished receiving the second packet 408. In one embodiment, the defined period is SIFS as defined by the IEEE 802.11 standard. In other embodiments, the defined period is another appropriate duration.

[0096] To avoid the transmission of the second packet 408 occurring simultaneously with the reception of the acknowledgment 412, the first communication device includes padding information 420 in packet 404 so that the end of packet 404 transmission occurs simultaneously with the end of packet 408 transmission. In the illustrative example in Figure 4, if the padding information 420 were not included in packet 404, the reception of the acknowledgment 412 would occur earlier than and overlapping with the transmission of packet 408. However, by including the padding information 420, the start of the reception of the acknowledgment 412 is delayed until after the end of the transmission of the second packet 408.

[0097] In some embodiments, if multiple transmissions within each frequency segment do not prompt an acknowledgment to begin after the end of the transmission for a defined period (e.g., SIFS or another suitable duration), the transmissions are permitted to terminate at different times, and therefore no padding, such as padding 420, is added to the packets. In other embodiments, even if multiple transmissions within each frequency segment do not prompt an acknowledgment to begin after the end of the transmission for a defined period (e.g., SIFS or another suitable duration), the transmissions are required to terminate simultaneously.

[0098] In some embodiments, when simultaneous transmission and reception within each frequency segment are permitted, the transmissions are permitted to terminate at different times, and therefore, no padding, such as padding 420, is added to the packets. In other embodiments, even when simultaneous transmission and reception within each frequency segment are permitted, padding, such as padding 420, is added to the packets so that the transmissions terminate simultaneously.

[0099] Figure 4 shows an example where two packets are transmitted simultaneously within two frequency segments, but in other embodiments, three or more packets are transmitted simultaneously within three or more frequency segments. In some embodiments, padding is added to two or more packets (similar to packet 404) so ​​that all transmissions of three or more packets are completed simultaneously.

[0100] Figure 5 is a flowchart of an exemplary method 500 for simultaneous transmission across multiple frequency segments according to one embodiment. In some embodiments, the multiple frequency segments correspond to respective communication links. In some embodiments, AP 114 and / or client station 154 are configured to implement method 500, and Figure 5 is described with reference to Figure 1 for illustrative purposes only. In other embodiments, method 500 is implemented by another suitable communication device.

[0101] In block 504, the communication device determines that simultaneous transmission and reception across multiple frequency segments is not permitted (for example, this is determined by network interface 122, MAC processor 126, synchronous transmission controller 146, network interface 162, MAC processor 166, synchronous transmission controller 196, etc.). For example, according to various embodiments, the step of determining in block 504 that simultaneous transmission and reception is not permitted includes (or does not include) one or more of the following steps: i) determining that a communication device implementing method 400 is not permitted to transmit and receive simultaneously across multiple frequency segments; ii) determining that another communication device that will receive future transmissions from the communication device as part of method 400 is not permitted to transmit and receive simultaneously across multiple frequency segments; and iii) determining that simultaneous transmission and reception across multiple frequency segments is not permitted within the WLAN on which the communication device operates.

[0102] In some embodiments, the step in block 504 of determining that simultaneous transmission and reception across multiple frequency segments is not permitted includes the step of determining that a communication device is not permitted to transmit and receive simultaneously across multiple frequency segments. In some embodiments, the step in block 504 of determining that simultaneous transmission and reception across multiple frequency segments is not permitted includes the step of receiving a packet from another communication device containing information indicating that another communication device is not permitted to transmit and receive simultaneously across multiple frequency segments, the other communication device would in the future transmit to another communication device as part of method 400. In some embodiments, the step in block 504 of determining that simultaneous transmission and reception across multiple frequency segments is not permitted includes the step of receiving a packet from an AP containing information indicating that simultaneous transmission and reception across multiple frequency segments is not permitted within a WLAN managed by the AP.

[0103] In block 508, the first packet is transmitted by the communication devices within a first frequency segment that begins at a first time (for example, by network interface 122, PHY processor 130, network interface 162, PHY processor 170, etc.). In block 512, the second packet is transmitted by the communication devices within a second frequency segment that begins at a second time different from the first time (for example, by network interface 122, PHY processor 130, network interface 162, PHY processor 170, etc.). The transmission of the second packet in block 512 overlaps in time with the transmission of the first packet in block 508.

[0104] In block 516, in response to the determination in block 504 that simultaneous transmission and reception across multiple frequency segments is not permitted, the communication devices (e.g., network interface 122, PHY processor 130, network interface 162, PHY processor 170, etc.) include padding in the first packet so that the end of transmission of the first packet occurs simultaneously with the end of transmission of the second packet. In some embodiments, a MAC processor (e.g., MAC processor 126, MAC processor 166, etc.) instructs a PHY processor (e.g., PHY processor 130, PHY processor 170, etc.) to include padding in the first packet so that the end of transmission of the first packet occurs simultaneously with the end of transmission of the second packet, and the PHY processor (e.g., PHY processor 130, PHY processor 170, etc.) determines the amount of padding to include in the first packet so that the end of transmission of the first packet occurs simultaneously with the end of transmission of the second packet.

[0105] In some embodiments, if the communication device determines in block 504 that simultaneous transmission and reception across multiple frequency segments are not permitted, the communication device (e.g., network interface 122 does not include it, PHY processor 130 does not include it, network interface 162 does not include it, PHY processor 170 does not include it, etc.) does not include padding in the first packet so that the end of transmission of the first packet occurs simultaneously with the end of transmission of the second packet. In some embodiments, the MAC processor (e.g., MAC processor 126, MAC processor 166, etc.) instructs the PHY processors (e.g., PHY processor 130, PHY processor 170, etc.) not include padding in the first packet so that the end of transmission of the first packet occurs simultaneously with the end of transmission of the second packet. In some embodiments, however, padding is added for purposes other than enabling a receiving device to spend more time generating a response to a packet, such as ensuring that the end of transmission of a first packet occurs simultaneously with the end of transmission of a second packet, such as ensuring that the modulated information ends on an OFDM symbol boundary.

[0106] In some embodiments, communication devices within a WLAN transmit simultaneously and synchronously across multiple frequency segments, for example, multiple transmissions across multiple frequency segments begin simultaneously. In some embodiments, communication devices within a WLAN are configured to perform both i) simultaneous transmission across multiple frequency segments, where multiple transmissions across multiple frequency segments are required to begin simultaneously, and ii) simultaneous and synchronous transmission across multiple frequency segments, where multiple transmissions across multiple frequency segments are required to begin simultaneously. For example, in some embodiments, at some times and / or under some circumstances, simultaneous transmissions across multiple frequency segments are required to begin simultaneously, while at other times and / or under other circumstances, simultaneous transmissions across multiple frequency segments are permitted to begin at different times. As an example, according to some embodiments, whether simultaneous transmissions across multiple frequency segments are required to begin simultaneously depends on the frequency distance between the multiple frequency segments. For example, in an exemplary embodiment, the first frequency segment is in the 2.4 GHz band. If the second frequency segment is within the 6 GHz band, simultaneous transmissions within multiple frequency segments are permitted to begin at different times. On the other hand, as another example, according to another exemplary embodiment, if the first frequency segment is within the 5 GHz band and the second frequency segment is within the 6 GHz band, or if the first and second frequency segments are within the same RF band, simultaneous transmissions within multiple frequency segments are required to begin simultaneously.

[0107] In some embodiments involving simultaneous and synchronous transmission across multiple frequency segments, the communication device performs each backoff operation (e.g., each backoff operation in each of the multiple frequency segments) using multiple backoff counters in the multiple frequency segments, and in response to all of the backoff counters having expired (e.g., all of the backoff counters reaching zero), it begins simultaneous and synchronous transmission across the multiple frequency segments.

[0108] Figure 6 is a flowchart of an exemplary method 600 for simultaneous transmission across multiple frequency segments that begin simultaneously, according to another embodiment. In some embodiments, the multiple frequency segments correspond to their respective communication links. In some embodiments, AP114 and / or client station 154 are configured to implement method 600, and Figure 6 is described with reference to Figure 1 for illustrative purposes only. In other embodiments, method 600 is implemented by another suitable communication device.

[0109] In block 604, the communication device determines whether multiple backoff counters corresponding to multiple frequency segments of the operating channel (e.g., backoff counter 142, backoff counter 192, etc.) have expired (e.g., reached zero) (e.g., the network interface 122 determines, the MAC processor 126 determines, the backoff controller 140 determines, the network interface 162 determines, the MAC processor 166 determines, the backoff controller 190 determines, etc.). For example, in one embodiment, the communication device maintains each backoff counter 142 / 192 for each frequency segment (e.g., the network interface 122 maintains, the MAC processor 126 maintains, the backoff controller 140 maintains, the network interface 162 maintains, the MAC processor 166 maintains, the backoff controller 190 maintains, etc.). In one embodiment, each backoff counter 142 / 192 corresponds to each subchannel within each frequency segment, and the backoff counter 142 / 192 is decremented when it is determined that each subchannel is idle, and suspended when it is determined that each subchannel is busy. In another embodiment, each backoff counter 142 / 192 corresponds to each primary subchannel within each frequency segment, and the backoff counter 142 / 192 is decremented when it is determined that each primary subchannel is idle, and suspended when it is determined that each primary subchannel is busy.

[0110] In response to the determination in block 604 that not all of the multiple backoff counters have expired (for example, one or more of the backoff counters have not expired), the communication devices wait until all of the multiple backoff counters have expired (for example, network interface 122 waits, MAC processor 126 waits, backoff controller 140 waits, network interface 162 waits, MAC processor 166 waits, backoff controller 190 waits, etc.).

[0111] In some embodiments, if one backoff counter has expired but one or more other backoff counters have not, method 600 includes a step of waiting until all backoff counters have expired.

[0112] In response to the determination in block 604 that all of the multiple backoff counters have expired, the flow proceeds to block 608. In block 608, the communication device determines whether all of any secondary subchannels within the operating channel are idle for a defined period prior to the commencement of transmission within the operating channel. In one embodiment, the defined period is a suitable duration, such as the Point Coordination Function (PCF) interframe interval (PIFS) as defined by the IEEE 802.11 standard. In other embodiments, the defined period is another suitable duration, such as the Distributed Coordination Function (DCF) interframe interval (DIFS) as defined by the IEEE 802.11 standard, the SIFS as defined by the IEEE 802.11 standard, or another suitable duration.

[0113] In response to the determination in block 608 that not all secondary subchannels within the operating channel are idle for a predetermined period prior to the commencement of transmission within the operating channel (for example, one or more secondary subchannels are busy), the flow proceeds to block 612. In block 612, no transmission occurs within the operating channel. In some embodiments, in relation to block 612, the multiple backoff counters are reset and flow 600 is repeated. In another embodiment, i) transmission occurs within multiple primary subchannels corresponding to multiple backoff counters and ii) transmission occurs within one or more idle secondary subchannels (if any).

[0114] On the other hand, in response to the determination in block 608 that all secondary subchannels within the operating channel are idle for a specified period prior to the commencement of transmission within the operating channel (for example, one or more of the secondary subchannels are busy), the flow proceeds to block 616. In block 616, transmission within the operating channel is performed, which includes simultaneous transmission across multiple frequency segments that begin simultaneously.

[0115] Figure 7 illustrates an example of simultaneous transmission within multiple frequency segments that begin at the same time, according to one embodiment. In some embodiments, the transmission 700 is performed according to method 600 of Figure 6. In other embodiments, the transmission 700 is performed according to another suitable method of simultaneous transmission within multiple frequency segments that begin at the same time.

[0116] The transmission 700 is located within an operating channel that includes a first frequency segment and a second frequency segment. In some embodiments, the first frequency segment corresponds to a first communication link, and the second frequency segment corresponds to a second communication link.

[0117] The communication devices perform a first backoff procedure 704 in relation to the first frequency segment (for example, by network interface 122, MAC processor 126, backoff controller 140, network interface 162, MAC processor 166, and backoff controller 190), and then perform a second backoff procedure 708 in relation to the second frequency segment (for example, by network interface 122, MAC processor 126, backoff controller 140, network interface 162, MAC processor 166, and backoff controller 190).

[0118] In some embodiments, performing the backoff procedure 704 includes decrementing a first backoff counter when it is determined that a subchannel in the first frequency segment is idle, and pausing the decrement of the first backoff counter when it is determined that a subchannel in the first frequency segment is not idle (e.g., busy). In some embodiments, performing the backoff procedure 704 includes decrementing a first backoff counter when it is determined that a primary subchannel in the first frequency segment is idle, and pausing the decrement of the first backoff counter when it is determined that a primary subchannel in the first frequency segment is not idle (e.g., busy).

[0119] In some embodiments, performing the backoff procedure 708 includes decrementing a second backoff counter when it is determined that a subchannel in the second frequency segment is idle, and pausing the decrement of the second backoff counter when it is determined that a subchannel in the second frequency segment is not idle (e.g., busy). In some embodiments, performing the backoff procedure 708 includes decrementing a second backoff counter when it is determined that a primary subchannel in the second frequency segment is idle, and pausing the decrement of the second backoff counter when it is determined that a primary subchannel in the second frequency segment is not idle (e.g., busy).

[0120] In the exemplary transmission 700 shown in Figure 7, the first backoff counter expires before the second backoff counter expires. In response to the first backoff counter expiring before the second backoff counter expires, the communication device postpones transmission within the first frequency segment until the second backoff counter expires (e.g., waits for transmission). In response to the second backoff counter expiring, the communication device transmits transmission 720, which includes the first transmission 724 within the first frequency segment and the second transmission 728 within the second frequency segment (e.g., network interface 122 transmits, PHY processor 130 transmits, network interface 162 transmits, PHY processor 170 transmits, etc.). The first transmission 724 and the second transmission 728 begin simultaneously.

[0121] In one embodiment, the first transmission 724 includes a first PHY data unit, and the second transmission 728 includes a PHY data unit packet. In another embodiment, the first transmission 724 and the second transmission 728 correspond to a single PHY data unit spanning an operating channel.

[0122] Figure 8 is a diagram illustrating another explanatory example of simultaneous transmission within multiple frequency segments that begin at the same time, according to a different embodiment. In some embodiments, transmission 800 is performed according to method 600 of Figure 6. In other embodiments, transmission 800 is performed according to another suitable method of simultaneous transmission within multiple frequency segments that begin at the same time.

[0123] The transmission 800 is located within an operating channel that includes a first frequency segment and a second frequency segment. In some embodiments, the first frequency segment corresponds to a first communication link, and the second frequency segment corresponds to a second communication link.

[0124] Transmission 800 is the same as transmission 700 in Figure 7, and for the sake of brevity, elements with the same number will not be described in detail.

[0125] In response to the first backoff counter expiring before the second backoff counter expiring, the communication device postpones the transmission of transmission 724 (e.g., waits for transmission) until the second backoff counter expires and transmits a padding signal 804. In response to the second backoff counter expiring, the communication device stops transmitting the padding signal 804 and begins transmitting transmission 720, which includes the first transmission 724 in the first frequency segment and the second transmission 728 in the second frequency segment (e.g., network interface 122 transmits, PHY processor 130 transmits, network interface 162 transmits, PHY processor 170 transmits, etc.). In one embodiment, transmission 724 includes a PHY preamble having a training field (e.g., a legacy short training field (L-STF)) or another suitable training field used by the receiver, particularly for packet detection. In some embodiments, the padding signal 804 has low cross-correlation with a training field in the PHY preamble used by the receiver for packet detection, so that the receiver is less likely to mistake the padding signal 804 for the start of a packet. Additionally or alternatively, according to some embodiments, the padding signal 804 is configured to prompt the receiving device to determine that the subchannel on which the padding signal 804 is transmitted is busy, thereby increasing the probability that no other communication device will attempt to transmit in the subchannel corresponding to the first transmission 724 between the time a first backoff counter expires and the time a second backoff counter expires.

[0126] Figures 7 and 8 show exemplary simultaneous transmissions within two frequency segments, but in other embodiments, three or more transmissions are transmitted simultaneously within each of the three or more frequency segments. With respect to Figure 8, in some embodiments, the padding is transmitted within two or more frequency segments.

[0127] Referring to Figures 6 to 8, in one embodiment, if frame transmission fails in relation to simultaneous transmission across multiple frequency segments (e.g., failure to receive frame acknowledgment), the CW value is adjusted for only one of the backoff counters (e.g., approximately twice, with CWmax as the upper limit) (e.g., the CW values ​​of one or more other backoff counters are kept the same). In another embodiment, if frame transmission fails within one frequency segment in relation to simultaneous transmission across multiple frequency segments (e.g., failure to receive frame acknowledgment), the CW value is adjusted for only the backoff counter corresponding to that one frequency segment (e.g., approximately twice, with CWmax as the upper limit) (e.g., the CW values ​​of one or more other backoff counters are kept the same). In yet another embodiment, if frame transmission fails within one frequency segment in relation to simultaneous transmission across multiple frequency segments (e.g., failure to receive frame acknowledgment), the CW value is adjusted for all of the backoff counters (e.g., approximately twice, with CWmax as the upper limit).

[0128] Figure 9 is a flowchart of another exemplary method 900, according to a different embodiment, for simultaneous transmission across multiple frequency segments that start simultaneously. In some embodiments, the multiple frequency segments correspond to their respective communication links. In some embodiments, AP114 and / or client station 154 are configured to implement method 900, and Figure 9 is described with reference to Figure 1 for illustrative purposes only. In other embodiments, method 900 is implemented by another suitable communication device.

[0129] In block 904, the communication device determines whether a single backoff counter (e.g., backoff counter 142, backoff counter 192, etc.) corresponding to a single frequency segment of the operating channel has expired (e.g., reached zero) (e.g., the network interface 122, MAC processor 126, backoff controller 140, network interface 162, MAC processor 166, backoff controller 190, etc.). In one embodiment, the backoff counters 142 / 192 correspond to subchannels within a single frequency segment, and the backoff counters 142 / 192 are decremented if the subchannel is determined to be idle, and decrementing is suspended if the subchannel is determined to be busy. In one embodiment, the backoff counter 142 / 192 corresponds to a primary subchannel within a single frequency segment, and the backoff counter 142 / 192 is decremented when the primary subchannel is determined to be idle, and the decrement is suspended when the primary subchannel is determined to be busy.

[0130] In response to the determination in block 904 that a single backoff counter has not yet expired, the communication devices wait until a single backoff counter expires (for example, network interface 122 waits, MAC processor 126 waits, backoff controller 140 waits, network interface 162 waits, MAC processor 166 waits, backoff controller 190 waits, etc.).

[0131] In response to the determination in block 904 that a single backoff counter has expired, the flow proceeds to block 908. In block 908, the communication device determines whether all other subchannels in the operating channel (e.g., subchannels other than the primary subchannel corresponding to the backoff counter) are idle for a defined period prior to the commencement of transmission within the operating channel. In one embodiment, the defined period is a suitable duration such as PIFS as defined by the IEEE 802.11 standard. In other embodiments, the defined period is another suitable duration such as DIFS as defined by the IEEE 802.11 standard, SIFS as defined by the IEEE 802.11 standard, or another suitable duration.

[0132] In response to the determination in block 908 that not all other subchannels within the operating channel are idle for a predetermined period prior to the commencement of transmission within the operating channel (for example, one or more of the other subchannels are busy), the flow proceeds to block 912. In block 912, no transmission occurs within the operating channel. In some embodiments, related to block 912, a single backoff counter is reset and flow 900 is repeated. In another embodiment, transmission occurs i) within the primary subchannel corresponding to the backoff counter and ii) within one or more other idle subchannels (if any).

[0133] On the other hand, in response to the determination in block 908 that all other subchannels within the operating channel are idle for a specified period prior to the commencement of transmission within the operating channel (for example, one or more of the secondary subchannels are busy), the flow proceeds to block 916. In block 916, transmission within the operating channel is performed, which includes simultaneous transmission across multiple frequency segments that begin simultaneously.

[0134] Figure 10 is a diagram illustrating an example of simultaneous transmission within multiple frequency segments that begin at the same time, according to one embodiment. In some embodiments, transmission 1000 is performed according to method 900 of Figure 9. In other embodiments, transmission 1000 is performed according to another suitable method of simultaneous transmission within multiple frequency segments that begin at the same time.

[0135] The transmission 1000 is located within an operating channel that includes a first frequency segment and a second frequency segment. In some embodiments, the first frequency segment corresponds to a first communication link, and the second frequency segment corresponds to a second communication link.

[0136] A communication device performs a backoff procedure 1004 in relation to a first frequency segment (e.g., a network interface 122, a MAC processor 126, a backoff controller 140, a network interface 162, a MAC processor 166, a backoff controller 190, etc.). In some embodiments, performing the backoff procedure 1004 includes decrementing a backoff counter when a subchannel in the first frequency segment is determined to be idle, and suspending the decrement of the backoff counter when a subchannel in the first frequency segment is determined to be not idle (e.g., busy). In some embodiments, performing the backoff procedure 1004 includes decrementing a backoff counter when a primary subchannel in the first frequency segment is determined to be idle, and suspending the decrement of the backoff counter when a primary subchannel in the first frequency segment is determined to be not idle (e.g., busy).

[0137] In response to the expiration of the backoff counter, the communication devices transmit transmission 1020, which includes a first transmission 1024 in the first frequency segment and a second transmission 1028 in the second frequency segment (for example, network interface 122 transmits, PHY processor 130 transmits, network interface 162 transmits, PHY processor 170 transmits, etc.). The first transmission 1024 and the second transmission 1028 begin simultaneously.

[0138] In one embodiment, the first transmission 1024 includes a first PHY data unit, and the second transmission 1028 includes a PHY data unit packet. In another embodiment, the first transmission 1024 and the second transmission 1028 correspond to a single PHY data unit spanning an operating channel.

[0139] In some embodiments, the frequency segments on which a backoff procedure is performed for transmissions that begin simultaneously across multiple frequency segments change over time. For example, in some embodiments, in connection with a first transmission across multiple frequency segments, a communication device selects a frequency segment from among the multiple frequency segments to perform a different backoff procedure than that used for a previous second transmission across the multiple frequency segments.

[0140] Figure 11 is a diagram illustrating an example of multiple sets of simultaneous transmissions 1100 according to one embodiment. In some embodiments, each set of transmissions among the multiple sets of transmissions 1100 is performed according to method 900 of Figure 9. In other embodiments, each set of transmissions among the multiple sets of transmissions 1100 is performed according to another suitable method of simultaneous transmission within multiple frequency segments that start at the same time.

[0141] The transmission 1100 set is located within an operating channel that includes a first frequency segment and a second frequency segment. In some embodiments, the first frequency segment corresponds to a first communication link, and the second frequency segment corresponds to a second communication link.

[0142] In relation to the first transmission set 1104, the communication devices perform a backoff procedure 1108 in relation to the first frequency segment (e.g., performed by network interface 122, MAC processor 126, backoff controller 140, network interface 162, MAC processor 166, backoff controller 190, etc.). In some embodiments, performing the backoff procedure 1108 includes decrementing a backoff counter when it is determined that a subchannel in the first frequency segment is idle, and suspending the decrement of the backoff counter when it is determined that a subchannel in the first frequency segment is not idle (e.g., busy). In some embodiments, performing the backoff procedure 1108 includes decrementing a backoff counter when it is determined that a primary subchannel in the first frequency segment is idle, and suspending the decrement of the backoff counter when it is determined that a primary subchannel in the first frequency segment is not idle (e.g., busy).

[0143] In response to the expiration of the backoff counter, the communication devices transmit a set of transmissions 1104, including a first transmission 1124 in the first frequency segment and a second transmission 1128 in the second frequency segment (for example, network interface 122 transmits, PHY processor 130 transmits, network interface 162 transmits, PHY processor 170 transmits, etc.). The first transmission 1124 and the second transmission 1128 begin simultaneously.

[0144] In one embodiment, the first transmission 1124 includes a first PHY data unit, and the second transmission 1128 includes a PHY data unit packet. In another embodiment, the first transmission 1124 and the second transmission 1128 correspond to a single PHY data unit spanning an operating channel.

[0145] In relation to the second transmission set 1134, the communication devices perform a backoff procedure 1138 in relation to the second frequency segment (e.g., performed by network interface 122, MAC processor 126, backoff controller 140, network interface 162, MAC processor 166, backoff controller 190, etc.). In some embodiments, performing the backoff procedure 1138 includes decrementing a backoff counter when it is determined that a subchannel in the second frequency segment is idle, and suspending the decrement of the backoff counter when it is determined that a subchannel in the second frequency segment is not idle (e.g., busy). In some embodiments, performing the backoff procedure 1138 includes decrementing a backoff counter when it is determined that a primary subchannel in the second frequency segment is idle, and suspending the decrement of the backoff counter when it is determined that a primary subchannel in the second frequency segment is not idle (e.g., busy).

[0146] In response to the expiration of the backoff counter, the communication devices transmit a set of transmissions 1134, including a first transmission 1144 in the first frequency segment and a second transmission 1148 in the second frequency segment (for example, network interface 122 transmits, PHY processor 130 transmits, network interface 162 transmits, PHY processor 170 transmits, etc.). The first transmission 1144 and the second transmission 1148 begin simultaneously.

[0147] In one embodiment, the first transmission 1144 includes a first PHY data unit, and the second transmission 1148 includes a PHY data unit packet. In another embodiment, the first transmission 1144 and the second transmission 1148 correspond to a single PHY data unit spanning an operating channel.

[0148] In relation to the third transmission set 1154, the communication devices perform a backoff procedure 1158 in relation to the first frequency segment (e.g., performed by network interface 122, MAC processor 126, backoff controller 140, network interface 162, MAC processor 166, backoff controller 190, etc.). In some embodiments, performing the backoff procedure 1158 includes decrementing a backoff counter when it is determined that a subchannel in the first frequency segment is idle, and suspending the decrement of the backoff counter when it is determined that a subchannel in the first frequency segment is not idle (e.g., busy). In some embodiments, performing the backoff procedure 1158 includes decrementing a backoff counter when it is determined that a primary subchannel in the first frequency segment is idle, and suspending the decrement of the backoff counter when it is determined that a primary subchannel in the first frequency segment is not idle (e.g., busy).

[0149] In response to the expiration of the backoff counter, the communication devices transmit a set of transmissions 1154, which includes a first transmission 1164 in the first frequency segment and a second transmission 1168 in the second frequency segment (for example, network interface 122 transmits, PHY processor 130 transmits, network interface 162 transmits, PHY processor 170 transmits, etc.). The first transmission 1164 and the second transmission 1168 begin simultaneously.

[0150] In one embodiment, the first transmission 1164 includes a first PHY data unit, and the second transmission 1168 includes a PHY data unit packet. In another embodiment, the first transmission 1164 and the second transmission 1168 correspond to a single PHY data unit spanning an operating channel.

[0151] Figures 10 and 11 show exemplary simultaneous transmissions within two frequency segments, but in other embodiments, three or more transmissions are transmitted simultaneously within each of the three or more frequency segments. With respect to Figure 11, in some embodiments, the backoff operation is performed within three or more frequency segments.

[0152] Figures 9 to 11 illustrate the execution of a backoff operation within a single frequency segment using only one backoff counter. In some embodiments, the communication device maintains multiple backoff counters for multiple frequency segments (e.g., network interface 122 maintains, MAC processor 126 maintains, backoff controller 140 maintains, network interface 162 maintains, MAC processor 166 maintains, backoff controller 190 maintains), and backoff counters corresponding to other frequency segments are ignored when at least one backoff counter corresponding to one frequency segment expires. In one embodiment, when another backoff counter corresponding to another frequency segment expires, the other backoff counters are reset as described above. In one embodiment, when another backoff counter corresponding to another frequency segment expires, the CW value is increased and the other backoff counters are reset as described above. In one embodiment, the CW value is increased by adding a value randomly or pseudo-randomly selected from the range [0,1]. In another embodiment, if another backoff counter corresponding to a different frequency segment expires, the CW value is kept the same as described above, and the other backoff counters are reset.

[0153] Referring to Figures 9 to 11, in one embodiment, if frame transmission fails in relation to simultaneous transmission across multiple frequency segments (e.g., failure to receive frame acknowledgment), the CW value is adjusted for only one of the backoff counters (e.g., approximately twice, with CWmax as the upper limit) (e.g., the CW values ​​of one or more other backoff counters are kept the same). In another embodiment, if frame transmission fails within one frequency segment in relation to simultaneous transmission across multiple frequency segments (e.g., failure to receive frame acknowledgment), the CW value is adjusted for only the backoff counter corresponding to that one frequency segment (e.g., approximately twice, with CWmax as the upper limit) (e.g., the CW values ​​of one or more other backoff counters are kept the same). In yet another embodiment, if frame transmission fails within one frequency segment in relation to simultaneous transmission across multiple frequency segments (e.g., failure to receive frame acknowledgment), the CW value is adjusted for all of the backoff counters (e.g., approximately twice, with CWmax as the upper limit).

[0154] In the various embodiments described above, the communication device determines whether a subchannel is idle by comparing the energy level measured within the subchannel with a threshold. In some embodiments, additionally or alternatively, the communication device determines whether a subchannel is idle by determining whether the network allocation vector (NAV) counter corresponding to the subchannel has expired (e.g., network interface 122, MAC processor 126, backoff controller 140, network interface 162, MAC processor 166, backoff controller 190, etc.). In some embodiments, the NAV counter indicates whether another communication device has control of the communication medium. For example, the NAV counter is set using duration information in the received frame, and the NAV counter is decremented at a predetermined rate. When the NAV counter expires (e.g., reaches zero), this indicates that none of the other communication devices currently have control of the communication medium.

[0155] Embodiment 1: A method for simultaneous transmission across multiple frequency segments, comprising: a step of determining in a communication device that simultaneous transmission and reception across multiple frequency segments is not permitted; a step of the communication device transmitting a first packet in a first frequency segment beginning at a first time; a step of the communication device transmitting a second packet in a second frequency segment beginning at a second time different from the first time, wherein the transmission of the second packet overlaps in time with the transmission of the first packet; and a step of including padding in the first packet in response to the determination that simultaneous transmission and reception across multiple frequency segments is not permitted, such that the end of the transmission of the first packet occurs simultaneously with the end of the transmission of the second packet.

[0156] Embodiment 2: The method according to Embodiment 1, wherein the step of determining that simultaneous transmission and reception over multiple frequency segments is not permitted is the step of determining that the communication device is not permitted to transmit and receive simultaneously over multiple frequency segments.

[0157] Embodiment 3: The method according to Embodiment 1, wherein the communication device is a first communication device, the step of transmitting the second packet within the second frequency segment includes the step of transmitting the second packet to the second communication device within the second frequency segment, and the step of determining that simultaneous transmission and reception over multiple frequency segments is not permitted includes the step of determining that the second communication device is not permitted to transmit and receive simultaneously over multiple frequency segments.

[0158] Embodiment 4: The method according to Embodiment 3, comprising the step of receiving a third packet from the second communication device in the first communication device, wherein the third packet contains information indicating that the second communication device is not permitted to transmit and receive simultaneously over multiple frequency segments.

[0159] Embodiment 5: The method according to Embodiment 1, wherein the step of determining that simultaneous transmission and reception across multiple frequency segments is not permitted is the step of determining that simultaneous transmission and reception across multiple frequency segments is not permitted within the wireless local area network (WLAN) to which the communication device belongs.

[0160] Embodiment 6: The method according to Embodiment 5, wherein the step of determining that simultaneous transmission and reception over multiple frequency segments is not permitted within the WLAN is the step of receiving a third packet from an access point managing the WLAN in the communication device, wherein the third packet contains information indicating that simultaneous transmission and reception over multiple frequency segments is not permitted within the WLAN.

[0161] Embodiment 7: The method of any one of embodiments 1 to 6, further comprising the step of prompting the physical layer (PHY) processor of the communication device to include the padding in the first packet in response to a determination that simultaneous transmission and reception across multiple frequency segments are not permitted, such that the termination of the transmission of the first packet occurs simultaneously with the termination of the transmission of the second packet.

[0162] Embodiment 8: A first communication device comprising a wireless network interface device configured to communicate over multiple frequency segments. The wireless network interface device includes one or more integrated circuit (IC) devices configured to: determine that simultaneous transmission and reception over multiple frequency segments are not permitted; control the wireless network interface device to transmit a first packet within a first frequency segment beginning at a first time; control the wireless network interface device to transmit a second packet within a second frequency segment beginning at a second time different from the first time, wherein the transmission of the second packet overlaps in time with the transmission of the first packet; and, in response to the determination that simultaneous transmission and reception over multiple frequency segments are not permitted, include padding in the first packet such that the end of the transmission of the first packet occurs simultaneously with the end of the transmission of the second packet.

[0163] Embodiment 9: The first communication device according to Embodiment 8, wherein one or more IC devices are configured to determine that the first communication device is not permitted to transmit and receive simultaneously over multiple frequency segments.

[0164] Embodiment 10: The first communication device according to Embodiment 8, wherein one or more IC devices are configured to control the wireless network interface device to transmit the second packet to the second communication device within the second frequency segment, and to determine that simultaneous transmission and reception across multiple frequency segments is not permitted, by determining that the second communication device is not permitted to transmit and receive simultaneously across multiple frequency segments.

[0165] Embodiment 11: The first communication device according to Embodiment 10, wherein one or more IC devices are configured to determine, using information in a third packet received from the second communication device, that the second communication device is not permitted to transmit and receive simultaneously over multiple frequency segments, and the information in the third packet indicates that the second communication device is not permitted to transmit and receive simultaneously over multiple frequency segments.

[0166] Embodiment 12: The first communication device according to Embodiment 8, wherein one or more IC devices are configured to determine that simultaneous transmission and reception over multiple frequency segments are not permitted, by determining that simultaneous transmission and reception over multiple frequency segments are not permitted within the WLAN to which the communication device belongs.

[0167] Embodiment 13: The first communication device according to Embodiment 12, wherein one or more IC devices are configured to determine, using information in a third packet received from an access point managing the WLAN, that simultaneous transmission and reception over multiple frequency segments is not permitted within the WLAN, and that the information in the third packet indicates that simultaneous transmission and reception over multiple frequency segments is not permitted within the WLAN.

[0168] Embodiment 14: The first communication device according to any one of Embodiments 8 to 13, wherein the wireless network interface has a physical layer (PHY) processor implemented on one or more IC devices, and the one or more IC devices are configured to prompt the PHY processor to include the padding in the first packet in response to a determination that simultaneous transmission and reception across multiple frequency segments are not permitted, such that the termination of the transmission of the first packet occurs simultaneously with the termination of the transmission of the second packet.

[0169] Embodiment 15: A method for simultaneous transmission within multiple frequency segments, comprising the steps of: performing a backoff operation in a communication device corresponding to one of the multiple frequency segments, wherein the backoff operation involves decrementing a backoff counter in relation to the one frequency segment; determining in the communication device whether the backoff counter has expired; and in response to the determination that the backoff counter has expired, the communication device simultaneously transmits each transmission within each simultaneously starting frequency segment.

[0170] Embodiment 16: The method according to Embodiment 15, further comprising the steps of: the communication device decrementing the backoff counter when it is determined that a subchannel within the one frequency segment is idle; and the communication device interrupting the decrementing of the backoff counter when it is determined that the subchannel within the one frequency segment is busy.

[0171] Embodiment 17: The method of Embodiment 16, further comprising the step of the communication device determining, in relation to the determination that the backoff counter has expired, whether one or more other subchannels in the plurality of frequency segments are idle for a predetermined period prior to the commencement of each of the transmissions in each of the frequency segments which commence simultaneously, and further the step of simultaneously transmitting each of the transmissions in each of the frequency segments which commence simultaneously, in response to the determination that one or more other subchannels in the plurality of frequency segments are idle for a predetermined period.

[0172] Embodiment 18: The method of Embodiment 17, further comprising the step of deciding to postpone the simultaneous transmission of each transmission within each of the frequency segments in response to the determination that one or more other subchannels within the plurality of frequency segments are busy for the predetermined period of time.

[0173] Embodiment 19: The method of any one of Embodiments 15 to 18, further comprising: the steps of: selecting a different frequency segment in the communication device in relation to a subsequent simultaneous transmission in a plurality of frequency segments; performing a different backoff operation in the communication device corresponding to the different frequency segment, the different backoff operation including decrementing the backoff counter or another backoff counter in relation to the different frequency segment; determining in the communication device whether the backoff counter or the other backoff counter has expired; and in response to the determination that the backoff counter or the other backoff counter has expired, the communication device performs the subsequent simultaneous transmission in the plurality of frequency segments.

[0174] Embodiment 20: The method according to any one of Embodiments 15 to 18, combined with the method according to any one of Embodiments 1 to 7.

[0175] Embodiment 21: A communication device comprising a wireless network interface device configured to communicate over a plurality of frequency segments, the wireless network interface device comprising one or more IC devices and a backoff counter mounted on the one or more IC devices. The one or more IC devices are configured to perform a backoff operation corresponding to one of the plurality of frequency segments, the backoff operation comprising performing a backoff operation, which involves decrementing the backoff counter in relation to the one frequency segment, determining whether the backoff counter has expired, and, in response to the determination that the backoff counter has expired, controlling the wireless network interface device to simultaneously transmit their respective transmissions within their respective simultaneously starting frequency segments.

[0176] Embodiment 22: The communication device according to Embodiment 21, wherein the one or more IC devices are further configured to decrement the backoff counter when it is determined that a subchannel in the one frequency segment is idle, and to suspend the decrement of the backoff counter when it is determined that the subchannel in the one frequency segment is busy.

[0177] Embodiment 23: The communication device according to Embodiment 22, wherein the one or more IC devices are further configured to perform, in connection with the determination that the backoff counter has expired, a determination that one or more other subchannels in the plurality of frequency segments are idle for a predetermined period prior to the commencement of each of the transmissions in each of the frequency segments, and, in response to the determination that one or more other subchannels in the plurality of frequency segments are idle for the predetermined period, a determination that the respective transmissions are transmitted simultaneously in each of the frequency segments.

[0178] Embodiment 24: The communication device according to Embodiment 23, wherein the one or more IC devices are further configured to perform a decision to postpone the simultaneous transmission of each transmission within each of the frequency segments in response to a determination that one or more other subchannels within the plurality of frequency segments are busy for a predetermined period of time.

[0179] Embodiment 25: A communication device according to any one of Embodiments 21 to 24, wherein the one or more IC devices are further configured to perform: selecting another frequency segment different from one of the frequency segments in relation to subsequent simultaneous transmissions within a plurality of frequency segments; performing another backoff operation corresponding to the other frequency segment different from one of the frequency segments, the other backoff operation including decrementing the backoff counter or another backoff counter in relation to the other frequency segment; determining whether the backoff counter or the other backoff counter has expired; and, in response to the determination that the backoff counter or the other backoff counter has expired, controlling the wireless network interface device to perform the subsequent simultaneous transmissions within the plurality of frequency segments.

[0180] Embodiment 26: A communication device according to any one of Embodiments 21 to 25, wherein the one or more IC devices are further configured to perform the operations described in any one of Embodiments 8 to 14.

[0181] At least some of the various blocks, operations, and techniques described above can be implemented using hardware, processors that execute firmware instructions, processors that execute software instructions, or any combination thereof. When implemented using processors that execute software or firmware instructions, the software or firmware instructions can be stored in any suitable computer-readable memory, such as random access memory (RAM), read-only memory (ROM), or flash memory. The software or firmware instructions may include machine-readable instructions that, when executed by one or more processors, cause one or more processors to perform various operations.

[0182] When implemented in hardware, the hardware may comprise one or more of the following: individual components, integrated circuits, application-specific integrated circuits (ASICs), programmable logic devices (PLDs), etc.

[0183] While the present invention has been described with reference to specific examples, these examples are intended to be illustrative only and not limiting, and modifications, additions, and / or deletions to the disclosed embodiments may be made without departing from the scope of the invention.

Claims

1. A method of simultaneous transmission within multiple frequency segments, The stage in which a communication device determines that simultaneous transmission and reception across multiple frequency segments are not permitted, The steps include: the communication device transmitting a first packet within a first frequency segment that begins at a first time; The communication device transmits a second packet within a second frequency segment that begins at a second time different from the first time, wherein the transmission of the second packet overlaps in time with the transmission of the first packet. In response to determining that simultaneous transmission and reception across multiple frequency segments are not permitted, the step of including padding in the first packet so that the termination of the transmission of the first packet occurs simultaneously with the termination of the transmission of the second packet. A method that includes [a certain feature].

2. The stage in which it is determined that simultaneous transmission and reception across multiple frequency segments are not permitted is: The stage in which it is determined that the communication device is not permitted to transmit and receive simultaneously across multiple frequency segments. Having, The method according to claim 1.

3. The aforementioned communication device is a first communication device, The step of transmitting the second packet within the second frequency segment includes the step of transmitting the second packet to a second communication device within the second frequency segment. The step of determining that simultaneous transmission and reception across multiple frequency segments is not permitted includes the step of determining that the second communication device is not permitted to transmit and receive simultaneously across multiple frequency segments. The method according to claim 1 or 2.

4. Before determining that the second communication device is not permitted to transmit and receive simultaneously across multiple frequency segments, A receiving step in which the first communication device receives a third packet from the second communication device, wherein the third packet includes information indicating that the second communication device is not permitted to transmit and receive simultaneously across multiple frequency segments. including, The method according to claim 3.

5. The stage in which it is determined that simultaneous transmission and reception across multiple frequency segments are not permitted is: The step of determining that simultaneous transmission and reception across multiple frequency segments is not permitted within the wireless local area network (WLAN) to which the communication device belongs. Having, The method according to any one of claims 1 to 4.

6. The step of determining that simultaneous transmission and reception across multiple frequency segments is not permitted within the WLAN is: A receiving step in which the communication device receives a third packet from an access point managing the WLAN, wherein the third packet includes information indicating that simultaneous transmission and reception across multiple frequency segments is not permitted within the WLAN. including, The method according to claim 5.

7. The method according to any one of claims 1 to 6, further comprising the step of prompting the physical layer (PHY) processor of the communication device to include the padding in the first packet in response to a determination that simultaneous transmission and reception across multiple frequency segments are not permitted, such that the termination of the transmission of the first packet occurs simultaneously with the termination of the transmission of the second packet.

8. A first communication device comprising a wireless network interface device configured to communicate over multiple frequency segments, wherein the wireless network interface device is It is determined that simultaneous transmission and reception across multiple frequency segments are not permitted, Controlling the wireless network interface device to transmit a first packet within a first frequency segment beginning at a first time; Controlling the wireless network interface device to transmit a second packet within a second frequency segment beginning at a second time different from the first time, wherein the transmission of the second packet overlaps in time with the transmission of the first packet. In response to determining that simultaneous transmission and reception across multiple frequency segments are not permitted, padding is included in the first packet such that the termination of the transmission of the first packet occurs simultaneously with the termination of the transmission of the second packet. One or more integrated circuit (IC) devices configured to perform Having, The first communication device.

9. The one or more IC devices are It is determined that the first communication device is not permitted to transmit and receive simultaneously across multiple frequency segments. It is configured in such a way. The first communication device according to claim 8.

10. The one or more IC devices are Controlling the wireless network interface device to transmit the second packet to the second communication device within the second frequency segment, At the very least, by determining that the second communication device is not permitted to transmit and receive simultaneously across multiple frequency segments, it is determined that simultaneous transmission and reception across multiple frequency segments is not permitted. Configured to perform, The first communication device according to claim 8 or 9.

11. The one or more IC devices are Using the information in the third packet received from the second communication device, it is determined that the second communication device is not permitted to transmit and receive simultaneously over multiple frequency segments, and that the information in the third packet indicates that the second communication device is not permitted to transmit and receive simultaneously over multiple frequency segments. Configured to perform, The first communication device according to claim 10.

12. The one or more IC devices are At a minimum, the determination that simultaneous transmission and reception across multiple frequency segments are not permitted is made by determining that simultaneous transmission and reception across multiple frequency segments are not permitted within the WLAN to which the first communication device belongs. Configured to perform, The first communication device according to any one of claims 8 to 11.

13. The one or more IC devices are Using information in a third packet received from an access point managing the WLAN, it is determined that simultaneous transmission and reception across multiple frequency segments are not permitted within the WLAN, and the information in the third packet indicates that simultaneous transmission and reception across multiple frequency segments are not permitted within the WLAN. Configured to perform, The first communication device according to claim 12.

14. The wireless network interface device has a physical layer (PHY) processor mounted on one or more IC devices. The one or more IC devices are configured to prompt the PHY processor to include the padding in the first packet in response to a determination that simultaneous transmission and reception across multiple frequency segments are not permitted, such that the termination of the transmission of the first packet occurs simultaneously with the termination of the transmission of the second packet. The first communication device according to any one of claims 8 to 13.

15. A method of simultaneous transmission within multiple frequency segments, A step of performing a backoff operation in a communication device corresponding to one of the plurality of frequency segments, wherein the backoff operation involves decrementing a backoff counter in relation to the one frequency segment. A step in which the communication device determines whether the backoff counter of the communication device has expired, In response to the determination that the backoff counter has expired, the communication device simultaneously transmits each transmission within each frequency segment that starts at the same time. A method that includes [a certain feature].

16. If it is determined that a subchannel within the aforementioned frequency segment is idle, the communication device decrements the backoff counter. If it is determined that the subchannel within the aforementioned frequency segment is busy, the communication device interrupts the decrement of the backoff counter. The method according to claim 15, further comprising:

17. In relation to the determination that the backoff counter has expired, the communication device determines whether one or more other subchannels within the plurality of frequency segments are idle for a predetermined period prior to the start of each transmission within each frequency segment. Furthermore, The step of simultaneously transmitting each of the transmissions within each of the frequency segments that begin simultaneously is further a response to the determination that one or more other subchannels within the plurality of frequency segments are idle for a predetermined period of time. The method according to claim 16.

18. Step 1: In response to the determination that one or more other subchannels within the plurality of frequency segments are busy for the predetermined period, decide to postpone the simultaneous transmission of each transmission within each of the frequency segments. The method according to claim 17, further comprising:

19. In relation to subsequent simultaneous transmissions within multiple frequency segments, The steps include selecting a different frequency segment from the aforementioned one in the communication device, A step of performing in the communication device another backoff operation corresponding to another frequency segment different from the one frequency segment, the other backoff operation including decrementing the backoff counter or another backoff counter in relation to the other frequency segment, A step in which the communication device determines whether the aforementioned backoff counter or the aforementioned other backoff counter has expired, In response to a determination that the backoff counter or another backoff counter has expired, the communication device performs the subsequent simultaneous transmission within the plurality of frequency segments. The method according to any one of claims 15 to 18, further comprising:

20. A wireless network interface device configured to communicate over multiple frequency segments, comprising one or more integrated circuit (IC) devices and a backoff counter mounted on the one or more IC devices, wherein the one or more IC devices are Performing a backoff operation corresponding to one of the multiple frequency segments, wherein the backoff operation involves decrementing the backoff counter in relation to the one frequency segment. To determine whether the aforementioned backoff counter has expired, In response to the determination that the backoff counter has expired, the wireless network interface device is controlled to transmit each transmission simultaneously within each frequency segment that starts at the same time. Configured to perform, Communication device.

21. The one or more IC devices further, If it is determined that a subchannel within the aforementioned frequency segment is idle, the backoff counter is decremented. If it is determined that the subchannel within the aforementioned frequency segment is busy, the decrement of the backoff counter is interrupted. Configured to perform, The communication device according to claim 20.

22. The one or more IC devices further, In connection with the determination that the backoff counter has expired, the determination is made as to whether one or more other subchannels within the plurality of frequency segments are idle for a predetermined period prior to the start of each transmission within each frequency segment, Further in response to the determination that one or more other subchannels within the plurality of frequency segments are idle over the predetermined period, the wireless network interface device is controlled to transmit each of the transmissions simultaneously within each of the frequency segments. Configured to perform, The communication device according to claim 21.

23. The one or more IC devices further, In response to the determination that one or more other subchannels within the plurality of frequency segments are busy during the predetermined period, it is decided to postpone the simultaneous transmission of each transmission within each of the frequency segments. Configured to perform, The communication device according to claim 22.

24. The one or more IC devices further relate to subsequent simultaneous transmissions within multiple frequency segments. Selecting a different frequency segment from the aforementioned one, Performing another backoff operation corresponding to a different frequency segment than the one frequency segment, wherein the other backoff operation includes decrementing the backoff counter or another backoff counter in relation to the other frequency segment. To determine whether the aforementioned backoff counter or the aforementioned other backoff counter has expired, In response to a determination that the backoff counter or another backoff counter has expired, the wireless network interface device is controlled to perform the subsequent simultaneous transmission within the multiple frequency segments. Configured to perform, A communication device according to any one of claims 20 to 23.

Images