PACKET (NDP) FEEDBACK REPORT

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application No.

62/444,501, filed January 10, 2017 the disclosure of which is incorporated herein by reference as if set forth in full.

TECHNICAL FIELD

[0002] Embodiments pertain to wireless networks and wireless communications. Some embodiments relate to wireless local area networks (WLANs) and Wi-Fi networks including networks operating in accordance with the Institute of Electrical and Electronics Engineers (IEEE) 802.11 family of standards. Some embodiments relate to IEEE 802.1 lax. Some embodiments relate to methods, computer readable media, and apparatus for differential encoding of multiple bits for a null data packet (NDP) feedback report.

BACKGROUND

[0003] Efficient use of the resources of a wireless local-area network (WLAN) is important to provide bandwidth and acceptable response times to the users of the WLAN. However, often, there are many devices trying to share the same resources and some devices may be limited by the communication protocol they use or by their hardware bandwidth.

BRIEF DESCRIPTION OF THE DRAWINGS

[0004] The present disclosure is illustrated by way of example and not limitation in the figures of the accompanying drawings, in which like references indicate similar elements and in which:

[0005] Fig. 1 illustrates a WLAN in accordance with some embodiments;

[0006] Fig. 2 illustrates a resource allocation frame exchange and uplink data communication between the AP of Fig. 1 and the high efficiency (HE) stations (STAs) of Fig. 1 according to some embodiments; [0007] Fig. 3 illustrates uplink (UL) null data packets (NDPs) from two of the three

STAs of Fig. 1 in the frequency and time domains, and further showing P-matrix rows of the UL NDPs included allocated resource blocks for resource request transmissions according to one embodiment;

[0008] Fig. 4 illustrates an example a radio architecture to implement some embodiments;

[0009] Fig 5 illustrates an algorithm for determining a value of bits within tone sets according to a currently proposed disadvantageous solution;

[0010] Fig. 6 illustrates an algorithm for determining a value of bits within tone sets according to one embodiment;

[0011] Fig. 7 illustrates a method to be performed at a STA according to one embodiment;

[0012] Fig. 8 illustrates a method to be performed at an AP according to one embodiment; and

[0013] Fig. 9 illustrates a block diagram of an example machine upon which any one or more of the techniques (e.g., methodologies) of some embodiments may be performed; and

DETAILED DESCRIPTION

[0014] The following description and the drawings sufficiently illustrate specific embodiments to enable those skilled in the art to practice them. Other embodiments may incorporate structural, logical, electrical, process, and other changes. Portions and features of some embodiments may be included in, or substituted for, those of other embodiments. Embodiments set forth in the claims encompass all available equivalents of those claims.

[0015] Fig. 1 illustrates a WLAN 100 in accordance with some embodiments. The

WLAN may comprise a basic service set (BSS) 100 that may include an access point (AP) 102, a plurality of high-efficiency (HE) (e.g., IEEE 802.1 lax) stations (STAs) 104, and a plurality of legacy (e.g., IEEE 802.1 ln/ac) STAs 106.

[0016] The AP 102 may use one of the IEEE 802.11 protocols to transmit and receive.

The AP 102 may be a base station. The AP 102 may use other communications protocols as well as the IEEE 802.1 1 protocol. The IEEE 802.11 protocol may be IEEE 802.1 lax. The IEEE 802.11 protocol may include using orthogonal frequency division multiple-access (OFDMA), time division multiple access (TDMA), and/or code division multiple access (CDMA), or a combination of the above. The IEEE 802.11 protocol may include a multiple access technique. For example, the IEEE 802.1 1 protocol may include space-division multiple access (SDMA) and/or multi-user multiple-input multiple-output (MU-MFMO). The AP 102 and/or HE STA 104 may use one or both of MU-MFMO and OFDMA. There may be more than one AP 102 that is part of an extended service set (ESS). A controller (not illustrated) may store information that is common to the more than one AP 102. The controller may have access to an external network such as the Internet.

[0017] The legacy STAs 106 may operate in accordance with one or more of IEEE

802.11 a/b/g/n/ac/ad/af/ah/aj, or another legacy wireless communication standard. The HE STAs 104 may be wireless transmit and receive devices such as cellular telephones, smart telephones, handheld wireless communication devices, wireless glasses, wireless watches, wireless personal devices, tablets, or other devices that may be transmitting and receiving using the IEEE 802.11 protocol such as IEEE 802.1 lax. In the shown figure, one of the HE STAs 104 is shown to be a smartphone 124, another to be a tablet 126 and another to be a laptop computer 128 by way of example. We will also at times refer to the three HE STAs 104 in Fig. 1 as STAs 124, 126 or 128. One or more illustrative HE STAs 104 may be operable by one or more user(s). The HE STAs 104 (e.g., 124, 126, or 128) may include any suitable processor-driven STA including, but not limited to, a desktop STA, a laptop STA, a server, a router, a switch, an access point, a smartphone, a tablet, wearable wireless device (e.g., bracelet, watch, glasses, ring, etc.) and so forth. In some embodiments, the HE STAs 104, AP 102, and/or legacy STAs 106 may be termed wireless communication devices or systems. In some embodiments, the HE STA 104 may be a "group owner" (GO) for peer-to-peer modes of operation where the HE STA 104 may perform some operations of an AP 102.

[0018] The AP 102 may communicate with legacy STAs 106 in accordance with legacy

IEEE 802.11 communication techniques. In example embodiments, the AP 102 may also be configured to communicate with HE STAs 104 in accordance with legacy IEEE 802.11 communication techniques.

[0019] In some embodiments, a HE frame may be configurable to have the same bandwidth as a channel. The bandwidth of a channel may be 20MHz, 40MHz, or 80MHz, 160MHz, 320MHz contiguous bandwidths or an 80+80MHz (160MHz) non-contiguous bandwidth. In some embodiments, the bandwidth of a channel may be 1 MHz, 1.25MHz, 2.03MHz, 2.5MHz, 5MHz and lOMHz, or a combination thereof or another bandwidth that is less or equal to the available bandwidth may also be used. In some embodiments, the bandwidth of the channels may be based on a number of active subcarriers in the frequency domain. For example, the bandwidths of the channels may include multiples of 26 (e.g., 26, 52, 104, 242 etc.) active subcarriers or tones that are spaced to amount to 20 MHz of bandwidth. In some embodiments, the bandwidth of the channels may include 256 tones within 20 MHz. In some embodiments, a 20 MHz channel may comprise 256 tones for a 256-point Fast Fourier Transform (FFT). In some embodiments, a different number of tones may be used. In some embodiments, the OFDMA structure may consists of a 26-subcarrier resource unit (RU), 52- subcarrier RU, 106-subcarrier RU, 242-subcarrier RU, 484-subcarrier RU or a 996-subcarrier RU, or a combination of the above. Resource allocations for a single user (SU) may consist of a 242 subcarrier RU, 484-subcarrier RU, 996-subcarrier RU or a 2x996-subcarrier RU.

[0020] A HE frame may include a number of spatial streams, which may be in accordance with MU-MIMO techniques. In some embodiments, a HE frame may be configured accordance with one or both of OFDMA and MU-MFMO. In some embodiments, the AP 102, HE STA 104, and/or legacy STA 106 may also implement different technologies such as code division multiple access (CDMA) 2000, CDMA 2000 IX, CDMA 2000 Evolution-Data Optimized (EV-DO), Interim Standard 2000 (IS-2000), Interim Standard 95 (IS-95), Interim Standard 856 (IS-856), Long Term Evolution (LTE), Global System for Mobile communications (GSM), Enhanced Data rates for GSM Evolution (EDGE), GSM EDGE (GERAN), IEEE 802.16 (i.e., Worldwide Interoperability for Microwave Access (WiMAX)), BlueTooth®, WiMAX, WiGig, or other technologies.

[0021] Some embodiments relate to HE communications. In accordance with some

IEEE 802.1 lax embodiments, an AP 102 may be arranged to contend for a wireless medium (e.g., during a contention period) to receive exclusive control of the medium for an TXOP. In some embodiments, the TXOP may be termed a transmission opportunity (TXOP). The AP 102 may transmit a HE trigger frame at the beginning of the TXOP. The AP 102 may transmit a time duration of the TXOP and channel information within the trigger frame. During the TXOP, HE ST As 104 may communicate with the AP 102 in accordance with a non-contention based multiple access technique such as OFDMA and/or MU-MIMO. This is unlike conventional WLAN communications in which devices communicate in accordance with a contention-based communication technique, rather than a multiple access technique. During the TXOP, the AP 102 may communicate with HE STAs 104 using one or more HE frames. During the TXOP, the HE STAs 104 may operate on a channel smaller than the operating range of the AP 102, while the legacy stations will refrain from communicating with the AP and set their Network Allocation Vectors (NAVs) accordingly. [0022] In accordance with some embodiments, during the transmission of the trigger frame, the HE STAs 104 may contend for the wireless medium, with the legacy STAs 106 being excluded from contending for the wireless medium. In some embodiments, the trigger frame may indicate an uplink (UL) UL-MU-MEVIO and/or UL OFDMA control period. In some embodiments, the trigger frame may indicate one or more portions of the TXOP that are contention based for some HE STA 104 and one or more portions of the TXOP that are not contention based.

[0023] In example embodiments, the HE STA 104 and/or the AP 102 are configured to perform the methods and operations herein described in conjunction with Figs. 1-6. The term Wi-Fi may refer to one or more of the IEEE 802.11 communication standards. AP and STA may refer to HE access point 102 and/or HE STA 104 as well as legacy STAs 106.

[0024] IEEE 802.1 lax defines a mechanism called a Null Data Packet (NDP) feedback report. The NDP mechanism under 802.1 lax allows a generation of very short responses to an AP's trigger frame by a large number of STAs. Each of those STAs responds to the trigger frame using UL MU-MIMO along with other STAs, transmitting only the physical layer (PHY) preamble of a packet without data payload (i.e. transmitting a UL NDP), and using orthogonal allocations indicated in the high-efficiency long training field (HE-LTF) in the PHY preamble. The AP can then perform energy or sequence detection on each of these allocations to determine the bits within each UL NDP and in this way to identify which STA sent each of the NDPs (with one or more bits allowing a determination of an allocation ID for the sending STA) and what is the feedback from the STA (energy/sequence detection). For example, the AP may ask, via the trigger frame, which of the STAs addressed by the trigger frame wishes to communicate with the AP (a resource request by the AP), and the STAs that wish to do so may respond with respective UL NDPs. Within each UL NDP, could be multiple bits per feedback type, with feedback from the STA coming in the form of a ON/OFF or Y/N by virtue of the setting of the bits in the various tone allocations of the STAs. The feedback types could for example include a resource request from the STA, a power save request from the STA, and so forth. As the various UL NDPs come in from various STA, the AP would know which allocations correspond to which STA, by virtue of the STA's predetermined allocation ID identifying the tones allocated to that particular STA.

[0025] In some embodiments, the HE STAs 104 and AP 102 can include one or more computer systems similar to that of the functional diagram of Fig. 4 and/or the example machine/system of Fig. 5. [0026] The wireless network 100 may allow an OFDMA uplink resource allocation through the use of a downlink (DL) trigger frame by the AP to a plurality of STAs, followed by uplink (UL) null data packets ( DPs) by the plurality of STAs sent in a MU-MEVIO communication back to the AP, according to some example embodiments of the present disclosure. In this environment, HE STAs 104 may communicate with AP 102, and transmit data on operating channels. In order to transmit data on the operating channels, the HE STAs may use tone sets of resource units (RUs), a bandwidth allocation including a number of subcarriers or tones defined in the frequency domain that may be allocated for signal transmission. The HE STAs 104 may be assigned tone sets by the AP, or they may randomly access the operating channels. With respect to the RUs, for example in a frequency band of 20 MHz, there may be a total of 9 RUs, each of the size of a basic RUs of 26 tones. The AP 102 may, in the DL trigger frame, assign one or more of tone sets within RUs to one or more HE STAs 104, and the HE STAs may subsequently transmit their UL NDPs based on their resource allocations in the trigger frame.

[0027] Fig. 2 depicts an illustrative schematic diagram of frame exchanges for an

OFDMA resource allocation using the WLAN 100 of Fig. 1, in accordance with one or more example embodiments of the present disclosure. In this illustrative example, STAs 124, 126 and 128, along with AP 102, correspond respectively to the HE STAs 104 and AP of Fig. 1 that were previously described.

[0028] As shown in Fig. 2, the AP 102, in a resource request phase, may send a DL trigger frame 203 to STAs 124, 126 and 128. Trigger frame 203 may inquire whether STAs 104 need to transmit data. The STAs that have data to transmit may send a UL OFDMA request by sending energy only on their assigned allocation ID in corresponding UL NDPs 220. For example, AP 102 may assign allocation IDs to associated STAs 124, 126 and 128 in trigger frame 203. The AP 102 may detect energy on one or more resource blocks from a ST A. For example, AP 102 may detect energy on resource blocks 204, 205 and 206 in the PHY preamble sent from STAs 124, 126 and 128 respectively. The allocation ID of a given ST A may correspond to predetermined tone sets, for example of 6 tones each (such as tone sets of 6 tones each within a RU) in addition to a P matrix code, to identify the resources on which the given STA is sending its UL NDP. Thus, an allocation ID may be indicated by tone set indices and P matrix code as a combination unique to one STA. Currently, an allocation ID uses the first P matrix row (P matrix 0) for up to the first 18 users, starting with the RU's tone set 0 and P matrix 0, and, for the 19 ^th STA, will move to the next P matrix row. [0029] Thus, having received the trigger frame 203, the ST As may then send resource requests to the AP 102 using UL DPs 220, the UL DPs using the respective allocation IDs assigned to the corresponding STA in the previous trigger frame by the AP. By way of example, each of the UL NDPs would make use of a code sequence in the high efficiency (HE) long training field (LTF) (HE-LTF) of a PHY preamble that corresponds to the allocation ID assigned to the corresponding STA by the AP in the previous trigger frame. For example, if AP 102 assigns allocation ID 1 to STA 124, STA 124 may utilize the resource block of the HE-LTF field corresponding to allocation ID 1. A resource block may be defined as a combination of a given spatial stream and a tone set, for example a tone set of 6 tones, in the frequency and time domains, wherein the spatial stream is a code sequence corresponding to a row of a P-matrix. Where a single spatial stream is contemplated, a resource block may simply correspond to a tone set, for example a tone set of 6 tones in the frequency and time domain.

[0030] When AP 102 receives resource request in the form of UL NDPs 220, where allocation ID 1 is used, AP 102, may determine that the corresponding STA 124 may require tone sets for transmission of its uplink data (e.g., UL data 210). AP 102 may acknowledge to the STAs that it received the resource requests or may directly assign resources without acknowledging to the requesting STA. AP 102 may send a second trigger frame (e.g., trigger frame 208) notifying STA 124 of assigned tone sets that may be available for transmission in the uplink direction.

[0031] In one embodiment, AP 102, in the second trigger frame 208, may assign tone sets based on the allocation ID associated with the energy received on the corresponding resource block in the associated UL NDP. For example, when STA 128 utilized resource block 206 to request resources, AP 102 may assign one or more tone sets and associate them with the allocation ID that the energy was detected on. As a result, STA 128 may determine that a resource is assigned to it based on the allocation ID. The resource assignment may be sent to the one or more STAs using a trigger frame. AP 102 may thus send a second trigger frame 208 opening regular uplink transmissions using assigned resources (tone sets and P matrix code) for STAs that requested access. Trigger frame 208 may include the acknowledgement for channel access requests (alternatively, a resource request ACK may be sent prior to trigger frame 208). After AP 102 receives the uplink data from the STAs 104, it may send ACKs 214, 215, and 216 to the respective STAs. In some embodiments, ACKs 214, 215, and 216 may also be transmitted in a single frame, a multi-user block acknowledgment (BlockAck) that may acknowledge the reception of data frames from all STAs. [0032] Fig. 3 depicts an illustrative transmission and reception of resource requests as described above, in accordance with the one or more embodiments of the disclosure.

[0033] In one embodiment, one or more STAs that want to transmit one or more UL data frames to an AP may initially send UL NDPs to the AP in response to a first trigger frame from the AP to the STAs in a first phase of the MU-MIMO communication between the AP and the STAs. The trigger frame may have assigned allocation IDs to various STAs or may be a trigger frame with unassigned allocation IDs that may be used for random access. STAs that have assigned allocation IDs in the trigger frame may use their allocation IDs in order to notify the AP that they have uplink data to transmit and that they need resources in order to be able to transmit. The STAs that do not have assigned allocation IDs may randomly select one of the unassigned allocation IDs that were advertised in the trigger frame. As explained above, a STA may transmit a preamble that may contain one or more training fields, for example, HE-LTFs. For example, STAs 126 and 128 may each transmit at least an HE-STF frame on the bandwidth used by the resource request trigger frame, followed by a HE-LTF frame, transmitted on the resources from the allocation ID. Legacy preambles (L-STF, L-LTF, and L-SIG) may be sent prior to the HE-STF. In the shown example, a resource block may include tone sets within an RU made of 26 tones. The RU may further be in a 4x4 P-matrix or in a 2x2 P-matrix or in a P- matrix of another configuration.

[0034] In the example of Fig. 3, STA 126 may transmit an UL NDP using the first row of the 4x4 P-matrix. The rows as shown in the figure extend in the vertical direction in Fig. 3 in the form of superimposed columns but referred to as "rows" herein, with each row corresponding to a distinct spatial stream. Referring back to STA 126, it is shown as transmitting energy on the 4th resource in the frequency domain (e.g., resource block 324) in the first row of the PxP matrix. In addition, STA 128 may transmit energy using the 4th row of the 4x4 P- Matrix, on the 6th resource in the frequency domain (e.g., resource block 326). It is understood that the above is only one example of utilizing a P-matrix and tone sets combination in order to determine a resource block. However, other examples may include using the frequency domain and the time domain by allocating an allocation ID to tone sets without needing to refer to a P- matrix row (in which case the shown resource blocks 324 or 326 would have stretched horizontally into the time domain and there would be no rows/rows shown.

[0035] In one embodiment, AP 102 may receive the UL NDPs 320 from STAs 124 and/or 126 in a combined UL MU-MFMO format. When receiving the resource request contained in one or more HE-LTF fields from respective UL NDPs, AP 102 may detect energy (for example, in the embodiment of Fig. 3, by correlation with the different sequences of the P- matrix in the different tone sets) on various resource blocks. When AP 102 detects energy on the allocation ID assigned to a STA, AP 102 may know that this STA has sent a resource request. When AP 102 detects energy on a resource block used for random access, it notes the resource block ID and uses this ID as the identifier for that STA.

[0036] Referring next to Fig. 4, a block diagram is shown of a wireless communication system such as STA 400 or AP 400 (hereinafter STA/AP 400) such as any of HE ST As 104, or AP 102 of Fig. 1, according to some demonstrative embodiments. A wireless communication system may include a wireless communication radio architecture in accordance with some demonstrative embodiments. The shown radio architecture may include radio front-end module (FEM) circuitry 410, radio integrated circuit (IC) circuitry 402 and baseband processor 409. In Fig. 4, it is to be noted that the representation of a single antenna may be interpreted to mean one or more antennas. Although Fig. 4 shows a single radio IC circuitry block 402, a single FEM circuitry block 410 and a single baseband processor block 409, these blocks are to be viewed as representing the possibility of one or more circuitry blocks, where potentially one set of distinct circuitry blocks, for example, a distinct FEM circuitry, and/or a distinct radio IC circuitry, would work to provide the relevant functionalities noted herein. As used herein, "processing circuitry" or "processor" may include one or more distinctly identifiable processor blocks. As used herein, "processing" may entail processing fully or processing partially; and "decoding" may entail decoding fully or decoding partially.

[0037] FEM circuitry 410 may include a receive signal path comprising circuitry configured to operate on Wi-Fi signals received from one or more antennas 401, to amplify the received signals and to provide the amplified versions of the received signals to the radio IC circuitry 402 for further processing. FEM circuitry 410 may also include a transmit signal path which may include circuitry configured to amplify signals provided by the radio IC circuitry 402 for wireless transmission by one or more of the antennas 401. The antennas may include directional or omnidirectional antennas, including, for example, dipole antennas, monopole antennas, patch antennas, loop antennas, microstrip antennas or other types of antennas suitable for transmission of RF signals. In some multiple-input multiple-output (MFMO) embodiments, the antennas may be effectively separated to take advantage of spatial diversity and the different channel characteristics that may result.

[0038] Radio IC circuitry 402 as shown may include a receive signal path which may include circuitry to down-convert signals received from the FEM circuitry 410 and provide baseband signals to baseband processor 409. The radio IC circuitry 402 may also include a transmit signal path which may include circuitry to up-convert baseband signals provided by the baseband processor 409 and provide RF output signals to the FEM circuitry 410 for subsequent wireless transmission by the one or more antennas 401. In addition, embodiments include within their scope the provision of a radio IC circuitry that allows transmission of LP-WU signals.

[0039] Baseband processing circuity 409 may include processing circuitry 414 that provides Wi-Fi functionality. In the instant description, the baseband processor 409 may include a memory 412, such as, for example, a set of RAM arrays in a Fast Fourier Transform or Inverse Fast Fourier Transform block (not shown) of the baseband processor 409 from and into which the processing circuitry 414 may read and write data, such as, for example, data relating to butterfly operations. Memory 412 may further store control logic. Processing circuitry 414 may implement control logic within the memory to process the signals received from the receive signal path of the radio IC circuitry 402. Baseband processor 409 is also configured to also generate corresponding baseband signals for the transmit signal path of the radio IC circuitry 402, and may further include physical layer (PHY) and medium access control layer (MAC) circuitry, and may further interface with application processor 406 for generation and processing of the baseband signals and for controlling operations of the radio IC circuitry 402.

[0040] In some demonstrative embodiments, the front-end module circuitry 410, the radio IC circuitry 402, and baseband processor 409 may be provided on a single radio card. In some other embodiments, the one or more antennas 401, the FEM circuitry 410 and the radio IC circuitry 402 may be provided on a single radio card. In some other embodiments, the radio IC circuitry 402 and the baseband processor 409 may be provided on a single chip or integrated circuit (IC).

[0041] In some other embodiments, the radio architecture of STA/AP 400 may be configured to transmit and receive signals transmitted using one or more modulation techniques other than OFDM or OFDMA, such as spread spectrum modulation (e.g., direct sequence code division multiple access (DS-CDMA) and/or frequency hopping code division multiple access (FH-CDMA)), time-division multiplexing (TDM) modulation, and/or frequency-division multiplexing (FDM) modulation, and On-Off Keying (OOK), although the scope of the embodiments is not limited in this respect.

[0042] In some demonstrative embodiments, the radio-architecture of STA/AP 400 may include other radio cards, such as a WiGig radio card, or a cellular radio card configured for cellular (e.g., 3GPP such as LTE, LTE-Advanced or 5G communications).

[0043] In some IEEE 802.11 embodiments, the radio architecture of STA/AP 400 may be configured for communication over various channel bandwidths including bandwidths having center frequencies of 900 MHz, 2.4 GHz, 5 GHz, and bandwidths of less than 5 MHz, or of about 1 MHz, 2 MHz, 2.5 MHz, 4 MHz, 5MHz, 8 MHz, 10 MHz, 16 MHz, 20 MHz, 40MHz, 80MHz (with contiguous bandwidths) or 80+80MHz (160MHz) (with non-contiguous bandwidths), or any combination of the above frequencies or bandwidths, or any frequencies or bandwidths between the ones expressly noted above. In some demonstrative embodiments, a 320 MHz channel bandwidth may be used. In a further embodiment, the radio architecture of STA/AP 400 may be configured to operate on center frequencies above 45 GHz. The scope of the embodiments is not limited with respect to the above frequencies however.

[0044] Referring still to Fig. 4, in some demonstrative embodiments, STA/AP 400 may further include an input unit 418, an output unit 419, a memory unit 408. STA/AP 400 may optionally include other suitable hardware components and/or software components. In some demonstrative embodiments, some or all of the components of STA/AP 400 may be enclosed in a common housing or packaging, and may be interconnected or operably associated using one or more wired or wireless links. In other embodiments, components of STA/AP 400 may be distributed among multiple or separate devices.

[0045] In some demonstrative embodiments, application processor 406 may include, for example, a Central Processing Unit (CPU), a Digital Signal Processor (DSP), one or more processor cores, a single-core processor, a dual-core processor, a multiple-core processor, a microprocessor, a host processor, a controller, a plurality of processors or controllers, a chip, a microchip, one or more circuits, circuitry, a logic unit, an Integrated Circuit (IC), an Application-Specific IC (ASIC), or any other suitable multi-purpose or specific processor or controller. Application processor 406 may execute instructions, for example, of an Operating System (OS) of STA/AP 400 and/or of one or more suitable applications.

[0046] In some demonstrative embodiments, input unit 418 may include, for example, one or more input pins on a circuit board, a keyboard, a keypad, a mouse, a touch-screen, a touch-pad, a track-ball, a stylus, a microphone, or other suitable pointing device or input device. Output unit 419 may include, for example, one or more output pins on a circuit board, a monitor, a screen, a touch-screen, a flat panel display, a Light Emitting Diode (LED) display unit, a Liquid Crystal Display (LCD) display unit, a plasma display unit, one or more audio speakers or earphones, or other suitable output devices.

[0047] In some demonstrative embodiments, memory unit 408 may include, for example, a Random-Access Memory (RAM), a Read-Only Memory (ROM), a Dynamic RAM (DRAM), a Synchronous DRAM (SD-RAM), a flash memory, a volatile memory, a non-volatile memory, a cache memory, a buffer, a short-term memory unit, a long-term memory unit, or other suitable memory units. Storage unit 417 may include, for example, a hard disk drive, a floppy disk drive, a Compact Disk (CD) drive, a CD-ROM drive, a DVD drive, or other suitable removable or non-removable storage units. Memory unit 408 and/or storage unit 417, for example, may store data processed by STA/AP 400.

[0048] Some demonstrative embodiments include a wireless communication device, such as baseband processor 409 of Fig. 4, including a memory, such as memory 412, and a processing circuitry, such as processing circuitry 414 coupled the memory. The processing circuitry to read data from and write data into the memory. For example, processing circuitry may read data from and write data into the memory, such as data regarding FFT and IFFT butterfly operations, which may be read and written into respective Random-Access Memory (RAM) banks of a memory. The processing circuitry may further encode an UL DP to an AP, similar to UL NDPs 220 of Fig. 2 or UL DPs 330 of Fig. 3. The UL NDP may be encoded on at least two tone sets that are used to encode at least two bits for conveying energy and information within each UL NDP, for example energy and information described above in relation to Figs. 2 and 3 being conveyed within resource blocks of the FE-LTF portion of each UL-NDP to the AP in order to indicate an identity of the device and its resource request.

[0049] For example, the UL NDP may be adapted to be transmitted over 9 RUs, where each of the 9 RUs consists of 26 tones, and each of the 26 tones includes 4 tone sets of 6 tones each (with 2 tones left over as null tones). Reference may be made for example to Fig. 3 which shows 9 RUs per FE-STFs in the frequency and time domains, with one of the RUs, the RU in resource block 324 for the UL NDP from STA 126, or one of the RUs, the RU in resource block 326 for the UL NDP from STA 128, including the tone sets that are used to convey energy within the UL NDP for that particular STA. Embodiments however are not so limited, and for example contemplate more than one RU being allocated to a STA for conveying its UL NDP information to the AP, or tone sets across RUs being so allocated. Embodiments advantageously contemplate using the processing circuitry to encode the UL NDP such that the number of bits encoded on tone sets of the UL-NDP is not less than a number, minus one, of one or more tone sets that are used to convey those bits. Thus, according to embodiments, where 3 tone sets are used to convey bits for the UL NDP, the number of bits thus communicated within the UL NDP would not be less than 2. According to current proposals for UL NDP encoding, each bit is to be encoded within 2 tone sets, meaning that 4 tones sets could convey only 2 bits, whereas four tones sets of current embodiments could convey at least 3 bits.

[0050] Some embodiments contemplate encoding the UL NDP on at least two tone sets which are to together encode at least two bits. The first bit of the at least two bits is to be encoded within at least a first set of the at least two tone sets. A subsequent bit of the at least two bits is to be encoded within a subsequent set of the at least two tone sets, and a value of the subsequent bit is to be based on a value of tones used to encode the first bit. The processing circuitry is further to cause transmission of the UL NDP to an AP, for example by sending baseband signals to a radio IC, a FEM and antennas for transmission to the AP.

[0051] Embodiments bring about the above advantage in a manner that will be explained in further detail below with respect to Figs. 5 and 6.

[0052] Referring next to Fig. 5, an example is shown of an algorithm 500 for determining a value of bits within tone sets according to currently proposed disadvantageous solutions. As seen inn Fig. 5, a resource allocation 540 may include four tone sets, for example four sets each including an equal number of tones, including SI, S2, S3 and S4. In the shown example, a value for each set of tones may be set such that the energy or power level within respective pairs of sets (the power level to be determined at the receiver (the AP)) can be compared at 542 to determine at 544 a value of a bit represented by each pair of sets. The power level per set may be determined at the AP by summing a power within each tone of a set. In Fig. 5, SI and S2 are used to convey a value for the first bit bl, while S3 and S4 are used to convey a value for the second bit b2. At operation 542, the K represents a decision scaling factor, which may have a value from 1-5, for example a value of 3, or any other integer value depending on application needs. At operation 542, in the shown example, where the power within SI (P_S1) is greater than a decision factor of K and the power within S2 (P S2), then bl is to be decoded at the AP as having a value of 1. However, if the reverse is true, that is, where P S2 is greater than a factor of K and P Sl, then bl is to be decoded at the AP as having a value of 0. In a similar fashion, in the shown example, where the power within S3 (P S3) is greater than a factor of K and the power within S4 (P S4), then b2 is to be decoded at the AP as having a value of 1. However, if the reverse is true, that is, where P S4 is greater than a factor of K and P S3, then b2 is to be decoded at the AP as having a value of 0. If the AP should determine the following conditions: that P Sl being greater than a factor of K and P S2 is not true, and further that P S2 being greater than a factor of K and P Sl is not true, then the AP would determine that no UL NDP was received from the given STA. It would be recognized by the skilled person that, where P-matrix rows are used, the AP would perform de-spreading for each P-matrix row in addition to the power comparisons above. The above scheme is disadvantageous because it requires each bit to be represented by two tone sets, therefore requiring twice as many tone sets to encode a given number of bits for a UL NDP of a particular STA. [0053] The following may be assumed in the context of some exemplary embodiments:

(1) tone sets may be orthogonal in the time/frequency/space domains (each being able to convey independent information); (2) one or two bits may be assigned for one STA feedback in an UL NDP allocated resource block; (3) to transmit one bit, for example the first bit, under a first option, two tone sets may be used, and under a second option, one set of tones using two rows of P-matrix may be used (that is, one bit may use two tone sets -with each set being adjacent to the other set or not - distinguishable from one another in the frequency domain in one P-matrix row, or one set of tones in two rows of P-matrix with the distinguishing feature being from the fact of the set being in two distinct rows); (4) channel estimation would not be necessary for energy detection of the bits; and (5) the AP and STAs have a prior agreement on tone sets and P- matrix spreading to use for a given UL-NDP, and those parameters may be provided to the STAs through a DL trigger frame from the AP to the STAs.

[0054] Some embodiments contemplate encoding the first bit, bl, in either two tone sets

(option 1), or using a combination of a tone set using 2 rows of P-matrix (option 2). Having thus encoded the first bit using at most 2 tone sets, embodiments contemplate encoding any subsequent bits, that is, b2, b3, etc., within respective subsequent tone sets (that is, within tone sets that are consecutive starting from the last set of tones used to encode bl). Thus, where option 1 is used to encode bl, then b2 through bn (with n being an integer) may be encoded within S3 through Sn (SI and S2 having been used to encode bl) such that the respective values of b2 through bn depend among other things on the value of bl. Where option 2 is used to encode bl, then b2 through bn may be encoded within S2 through Sn (only SI and two rows of P-matrix having been used to encode bl) such that the respective values of b2 through bn depend among other things on the value of bl .

[0055] An example algorithm 600 for option 1 is shown in Fig. 6. In this example, a resource allocation 640 such as a RU may include four tone sets, for example four sets each including an equal number of tones, including SI, S2, S3 and S4. In the shown example, a value for each set of tones may be set such that the energy or power level within the first pair of tone sets SI and S2 (the power level to be determined at the receiver (the AP)) can be compared at 642 to determine at 644 a value of bl . The power level per set may be determined at the AP by summing a power within each tone of a set (determining a sum of powers associated with respective tones). In Fig. 6, SI and S2 are used to convey a value for the first bit bl, while S3 and S4 are used to convey a value for respective ones of b2 and b3 (the third bit). At operation 642, the K represents a predetermined decision scaling factor, which may have a value from 1-5, for example a value of 3. This factor may be known only at the AP side, or may be agreed upon between the STA and the AP. It may further be hardwired into the circuitry as a fixed value, or it may be variable based on application needs. At operation 642, in the shown example, where the power within SI (P_S1) is greater than a factor of K and the power within S2 (P_S2), then bl is to be decoded at the AP as having a value of 1. However, if the reverse is true, that is, where P_S2 is greater than a factor of K and P Sl, then bl is to be decoded at the AP as having a value of 0. Moving forward however into subsequent sets, in the shown example, the manner in which the power within subsequent tone sets are set depends on the value of bl . Thus:

a. where the value of bl is equal to 1 (where P_S1>K.P_S2), and the value of b2 is to be equal to 1, then the power within S3 (P S3) is set to be equal to P Sl, which would mean that P_S3>K.P_S2, which would signify to the AP that b2=l; b. where the value of bl is equal to 1 (where P_S1>K.P_S2), and the value of b2 is to be equal to 0, then the power within S3 (P S3) is set to be equal to P S2, which would mean that P_S1>K.P_S3, which would signify to the AP that b2=0; c. where the value of bl is equal to 0 (where P_S2>K.P_S1), and the value of b2 is to be equal to 1, then the power within S3 (P S3) is set to be equal to P Sl, which would mean that P_S2>K.P_S3, which would signify to the AP that b2=l; d. where the value of bl is equal to 0 (where P_S2>K.P_S1), and the value of b2 is to be equal to 0, then the power within S3 (P S3) is set to be equal to P S2, which would mean that P_S3>K.P_S1, which would signify to the AP that b2=0.

From the above, we can see that when P S3 = P Sl, then b2=l, and when P_S3=P_S2, then b2=0.

The UL DP could thus be encoded such that bits subsequent to the first bit, such as bn, have values that are dependent on tone values of a set of tones used to encode the first bit. It would be recognized by the skilled person that, where P-matrix rows are used, the AP would perform de-spreading for each P-matrix row in addition to the power comparisons above. In such a case, instead of referring to merely the power within sets of tones as denoted by "S" in the description above, one could refer more generally to a "code" or "C" for each power level. The "C" could denote either a set of tones (similar to the already used "S"), or, where option 2 is used, it could refer to a combination including a set of tones along with a P matrix code. In either case, the conditions noted in items a. through d. above would apply substituting the "S"'s with "C"'s for option 2.

[0056] It is to be noted, with respect to the description of Fig. 6 above, and with respect to embodiments, that the particular comparisons shown and described in Fig. 6 as between the respective power levels of the respective tone sets to allow a determination of a value of corresponding bits are not to be seen as limiting. Any predetermined and agreed upon sets of relationships between those power levels that would allow the STA to encode its UL NDP in a manner that would allow the AP to decode its bits would be within the purview of embodiments.

[0057] According to some embodiments, a DL trigger frame from an AP, such as DL trigger frame 203 of Fig. 2, may include parameters or information on an encoding of the UL NDPs, and specifically on the encoding of the bits within tone sets to be allocated to the STA, to allow the AP and STAs to allocate resources using the UL NDP mechanism described previously. Thus, the trigger frame may include information on at least one of: a number of tone sets that encodes the bits; a number of tone sets that encodes the first bit, a number of tone sets that encodes one or more subsequent bits, and a relationship between a value of each of the bits and respective sums of powers associated with tones of each respective one of the tone sets.

[0058] Fig 7 illustrates a first embodiment of a method to be implemented at a wireless communication device, such as at STA 400 of Fig. 4. The method 700 in Fig. 7 includes, at operation 702, reading and writing data into a memory; and at operation 704, encoding an uplink (UL) null data packet (NDP) on at least two tone sets, the at least two tone sets together encoding at least two bits, wherein: a first bit of the at least two bits is to be encoded within at least a first set of the at least two tone sets; and a subsequent bit of the at least two bits that is subsequent to the first bit is to be encoded within a subsequent set of the at least two tone sets that is subsequent to the at least first set, and such that a value of the subsequent bit is based on a value of tones used to encode the first bit. At operation 710, the method further includes causing transmission of the UL NDP to an access point (AP).

[0059] Fig 8 illustrates a first embodiment of a method to be implemented at a wireless communication device, such as at AP 400 of Fig. 4. The method 800 in Fig. 8 includes, at operation 802, reading and writing data into the memory; at operation 804, causing transmission of a downlink (DL) multi-user (MU) multiple-input multiple output (MEVIO) trigger frame to a plurality of wireless stations (STAs); and at operation 806, decoding an uplink (UL) MU-MTMO frame from at least some of the plurality of STAs, the UL MU-MIMO frame including respective uplink (UL) null data packets (NDPs) from respective ones of the STAs, each UL NDP of the respective UL NDPs on at least two tone sets together encoding at least two bits. The method further includes, at operation 808, determining a value of a first bit of the at least two bits by decoding at least a first set of the at least two tone sets; at operation 810, determining a value of a subsequent bit of the at least two bits that is subsequent to the first bit by decoding a subsequent set of the at least two tone sets that is subsequent to the at least first set, a value of the subsequent bit being based on a value of the first bit; and at operation 812, causing communication with the at least some of the plurality of STAs based on the value of the first bit and the value of the subsequent bit within said each UL DP.

[0060] Fig. 9 illustrates a block diagram of an example machine 900 upon which any one or more of the techniques (e.g., methodologies) discussed herein may perform. In alternative embodiments, the machine 900 may operate as a standalone device or may be connected (e.g., networked) to other machines. In a networked deployment, the machine 900 may operate in the capacity of a server machine, a client machine, or both in server-client network environments. In an example, the machine 900 may act as a peer machine in peer-to- peer (P2P) (or other distributed) network environment. The machine 900 may be an AP 102, HE STA 104, personal computer (PC), a tablet PC, a set-top box (STB), a personal digital assistant (PDA), a mobile telephone, a smart phone, a web appliance, a network router, switch or bridge, or any machine capable of executing instructions (sequential or otherwise) that specify actions to be taken by that machine. Further, while only a single machine is illustrated, the term "machine" shall also be taken to include any collection of machines that individually or jointly execute a set (or multiple sets) of instructions to perform any one or more of the methodologies discussed herein, such as cloud computing, software as a service (SaaS), other computer cluster configurations.

[0061] Examples, as described herein, may include, or may operate on, logic or a number of components, modules, or mechanisms. Modules are tangible entities (e.g., hardware) capable of performing specified operations and may be configured or arranged in a certain manner. In an example, circuits may be arranged (e.g., internally or with respect to external entities such as other circuits) in a specified manner as a module. In an example, the whole or part of one or more computer systems (e.g., a standalone, client or server computer system) or one or more hardware processors may be configured by firmware or software (e.g., instructions, an application portion, or an application) as a module that operates to perform specified operations. In an example, the software may reside on a machine readable medium. In an example, the software, when executed by the underlying hardware of the module, causes the hardware to perform the specified operations.

[0062] Accordingly, the term "module" is understood to encompass a tangible entity, be that an entity that is physically constructed, specifically configured (e.g., hardwired), or temporarily (e.g., transitorily) configured (e.g., programmed) to operate in a specified manner or to perform part or all of any operation described herein. Considering examples in which modules are temporarily configured, each of the modules need not be instantiated at any one moment in time. For example, where the modules comprise a general-purpose hardware processor configured using software, the general-purpose hardware processor may be configured as respective different modules at different times. Software may accordingly configure a hardware processor, for example, to constitute a particular module at one instance of time and to constitute a different module at a different instance of time.

[0063] Machine (e.g., computer system) 900 may include a hardware processor 902

(e.g., a central processing unit (CPU), a graphics processing unit (GPU), a hardware processor core, or any combination thereof), a main memory 904 and a static memory 906, some or all of which may communicate with each other via an interlink (e.g., bus) 908. The machine 900 may further include a display device 910, an input device 912 (e.g., a keyboard), and a user interface (UI) navigation device 914 (e.g., a mouse). In an example, the display device 910, input device 912 and UI navigation device 914 may be a touch screen display. The machine 900 may additionally include a mass storage (e.g., drive unit) 916, a signal generation device 918 (e.g., a speaker), a network interface device 920, and one or more sensors 921, such as a global positioning system (GPS) sensor, compass, accelerometer, or other sensor. The machine 900 may include an output controller 928, such as a serial (e.g., universal serial bus (USB), parallel, or other wired or wireless (e.g., infrared(IR), near field communication (NFC), etc.) connection to communicate or control one or more peripheral devices (e.g., a printer, card reader, etc.). In some embodiments, the processor 902 and/or instructions 924 may comprise processing circuitry and/or transceiver circuitry.

[0064] The storage device 916 may include a machine readable medium 922 on which is stored one or more sets of data structures or instructions 924 (e.g., software) embodying or utilized by any one or more of the techniques or functions described herein. The instructions 924 may also reside, completely or at least partially, within the main memory 904, within static memory 906, or within the hardware processor 902 during execution thereof by the machine 900. In an example, one or any combination of the hardware processor 902, the main memory 904, the static memory 906, or the storage device 916 may constitute machine readable media.

[0065] While the machine readable medium 922 is illustrated as a single medium, the term "machine readable medium" may include a single medium, or multiple media (e.g., a centralized or distributed database, and/or associated caches and servers) configured to store the one or more instructions 924.

[0066] An apparatus of the machine 900 may be one or more of a hardware processor

902 (e.g., a central processing unit (CPU), a graphics processing unit (GPU), a hardware processor core, or any combination thereof), a main memory 904 and a static memory 906, some or all of which may communicate with each other via an interlink (e.g., bus) 908.

[0067] The term "machine readable medium" may include any medium that is capable of storing, encoding, or carrying instructions for execution by the machine 900 and that cause the machine 900 to perform any one or more of the techniques of the present disclosure, or that is capable of storing, encoding or carrying data structures used by or associated with such instructions. Non-limiting machine readable medium examples may include solid-state memories, and optical and magnetic media. Specific examples of machine readable media may include: non-volatile memory, such as semiconductor memory devices (e.g., Electrically Programmable Read-Only Memory (EPROM), Electrically Erasable Programmable Read-Only Memory (EEPROM)) and flash memory devices; magnetic disks, such as internal hard disks and removable disks; magneto-optical disks; Random Access Memory (RAM); and CD-ROM and DVD-ROM disks. In some examples, machine readable media may include non-transitory machine-readable media. In some examples, machine readable media may include machine readable media that is not a transitory propagating signal.

[0068] The instructions 924 may further be transmitted or received over a communications network 926 using a transmission medium via the network interface device 920 utilizing any one of a number of transfer protocols (e.g., frame relay, internet protocol (IP), transmission control protocol (TCP), user datagram protocol (UDP), hypertext transfer protocol (HTTP), etc.). Example communication networks may include a local area network (LAN), a wide area network (WAN), a packet data network (e.g., the Internet), mobile telephone networks (e.g., cellular networks), Plain Old Telephone (POTS) networks, and wireless data networks (e.g., Institute of Electrical and Electronics Engineers (IEEE) 802.11 family of standards known as Wi-Fi®, IEEE 802.16 family of standards known as WiMAX®), IEEE 802.15.4 family of standards, a Long Term Evolution (LTE) family of standards, a Universal Mobile Telecommunications System (UMTS) family of standards, peer-to-peer (P2P) networks, among others.

[0069] In an example, the network interface device 920 may include one or more physical jacks (e.g., Ethernet, coaxial, or phone jacks) or one or more antennas to connect to the communications network 926. In an example, the network interface device 920 may include one or more antennas 960 to wirelessly communicate using at least one of single-input multiple- output (SFMO), multiple-input multiple-output (MFMO), or multiple-input single-output (MISO) techniques. In some examples, the network interface device 920 may wirelessly communicate using Multiple User MFMO techniques. The term "transmission medium" shall be taken to include any intangible medium that is capable of storing, encoding or carrying instructions for execution by the machine 900, and includes digital or analog communications signals or other intangible medium to facilitate communication of such software.

[0070] Various embodiments may be implemented fully or partially in software and/or firmware. This software and/or firmware may take the form of instructions contained in or on a non-transitory computer-readable storage medium. Those instructions may then be read and executed by one or more processors to enable performance of the operations described herein. The instructions may be in any suitable form, such as but not limited to source code, compiled code, interpreted code, executable code, static code, dynamic code, and the like. Such a computer-readable medium may include any tangible non-transitory medium for storing information in a form readable by one or more computers, such as but not limited to read only memory (ROM); random access memory (RAM); magnetic disk storage media; optical storage media; flash memory, etc.

[0071] EXAMPLES

[0072] The following examples pertain to further embodiments.

[0073] Example 1 includes a wireless communication device including a memory, and a processing circuitry coupled the memory, the processing circuitry to: read data from and write data into the memory; encode an uplink (UL) null data packet ( DP) on at least two tone sets, the at least two tone sets together encoding at least two bits, wherein: a first bit of the at least two bits is to be encoded within at least a first set of the at least two tone sets; and a subsequent bit of the at least two bits that is subsequent to the first bit is to be encoded: within a subsequent set of the at least two tone sets that is subsequent to the at least first set; and such that a value of the subsequent bit is based on a value of tones used to encode the first bit; and cause transmission of the UL NDP to an access point (AP).

[0074] Example 2 includes the subject matter of Example 1, and optionally, wherein the at least a first set consists of a first set and a second set of the at least two tone sets.

[0075] Example 3 includes the subject matter of Example 1, and optionally, wherein the first bit is to be encoded within a combination of the first set of the at least two tone sets and two rows of P-matrix.

[0076] Example 4 includes the subject matter of Example 2, and optionally, wherein the at least two tone sets consist of three tone sets, the three tone sets encoding three bits.

[0077] Example 5 includes the subject matter of Example 2, and optionally, wherein the processing circuitry is to set tone values for the first set and the second set such that: to encode a first value for the first bit, a sum of powers associated with respective tones of the first set is greater than a sum of powers associated with respective tones of the second set multiplied by a predetermined decision scaling factor; and to encode a second value for the first bit, a sum of powers associated with respective tones of the second set is greater than a sum of powers associated with respective tones of the first set multiplied by a predetermined decision scaling factor.

[0078] Example 6 includes the subject matter of Example 5, and optionally, wherein the processing circuitry is to set tone values for the subsequent set such that: to encode a first value for the subsequent bit, a sum of powers associated with respective tones of the subsequent set is equal to a sum of powers associated with respective tones of the first set; and to encode a second value for the subsequent bit, the sum of powers associated with tones of the subsequent set is equal to a sum of powers associated with tones of the second set.

[0079] Example 7 includes the subject matter of Example 5, and optionally, wherein the predetermined decision factor is between 1 and 5.

[0080] Example 8 includes the subject matter of any one of claims 1-7, wherein the UL

NDP consists of 9 RUs, each of the 9 RUs consisting of 26 tones, and each set of 26 tones being divided into 4 tone sets of 6 tones each.

[0081] Example 9 includes the subject matter of any one of Examples 1-7, and optionally, wherein the processing circuitry is further to: decode a trigger frame from the access point, the trigger frame including information on an encoding of the at least two bits within the at least two tone sets; and encode the UL NDP based on a decoding of the trigger frame.

[0082] Example 10 includes the subject matter of Example 9, and optionally, wherein the information is based on at least one of: a number of tone sets that encodes the bits; a number of tone sets that encodes the first bit, a number of tone sets that encodes one or more subsequent bits, and a relationship between a value of each of the bits and respective sums of powers associated with tones of each respective one of the tone sets.

[0083] Example 11 includes the subject matter of Example 1, and optionally, further including a radio integrated circuit coupled to the processing circuitry, and a front-end module coupled to the radio integrated circuit.

[0084] Example 12 includes the subject matter of Example 11, and optionally, further including a plurality of antennas coupled to the front-end module.

[0085] Example 13 includes a product comprising one or more tangible computer- readable non-transitory storage media comprising computer-executable instructions operable to, when executed by at least one computer processor, enable the at least one computer processor to implement operations at a wireless communication device, the operations comprising: reading and writing data into a memory; encoding an uplink (UL) null data packet (NDP) on at least two tone sets, the at least two tone sets together encoding at least two bits, wherein: a first bit of the at least two bits is to be encoded within at least a first set of the at least two tone sets; and a subsequent bit of the at least two bits that is subsequent to the first bit is to be encoded: within a subsequent set of the at least two tone sets that is subsequent to the at least first set; and such that a value of the subsequent bit is based on a value of tones used to encode the first bit; and causing transmission of the UL NDP to an access point (AP).

[0086] Example 14 includes the subject matter of Example 13, and optionally, wherein the at least a first set consists of a first set and a second set of the at least two tone sets.

[0087] Example 15 includes the subject matter of Example 13, and optionally, wherein the first bit is to be encoded within a combination of the first set of the at least two tone sets and two rows of P-matrix.

[0088] Example 16 includes the subject matter of Example 14, and optionally, wherein the at least two tone sets consist of three tone sets, the three tone sets encoding three bits.

[0089] Example 17 includes the subject matter of Example 14, and optionally, wherein the operations further include setting tone values for the first set and the second set such that: to encode a first value for the first bit, a sum of powers associated with respective tones of the first set is greater than a sum of powers associated with respective tones of the second set multiplied by a predetermined decision scaling factor; and to encode a second value for the first bit, a sum of powers associated with respective tones of the second set is greater than a sum of powers associated with respective tones of the first set multiplied by a predetermined decision scaling factor.

[0090] Example 18 includes the subject matter of Example 17, and optionally, wherein the operations further include setting tone values for the subsequent set such that: to encode a first value for the subsequent bit, a sum of powers associated with respective tones of the subsequent set is equal to a sum of powers associated with respective tones of the first set; and to encode a second value for the subsequent bit, the sum of powers associated with tones of the subsequent set is equal to a sum of powers associated with tones of the second set.

[0091] Example 19 includes the subject matter of Example 17, and optionally, wherein the predetermined decision factor is between 1 and 5.

[0092] Example 20 includes the subject matter of any one of Examples 13-19, and optionally, wherein the UL NDP consists of 9 RUs, each of the 9 RUs consisting of 26 tones, and each set of 26 tones being divided into 4 tone sets of 6 tones each. [0093] Example 21 includes the subject matter of any one of Examples 13-19, the operations further including decoding a trigger frame from the access point, the trigger frame including information on an encoding of the at least two bits within the at least two tone sets.

[0094] Example 22 includes the subject matter of Example 21, and optionally, wherein the information is based on at least one of: a number of tone sets that encodes the bits; a number of tone sets that encodes the first bit, a number of tone sets that encodes one or more subsequent bits, and a relationship between a value of the bits and respective sums of powers associated with tones of each respective one of the tone sets.

[0095] Example 23 includes a method to be performed at a wireless communication device that includes a memory and a processing circuitry coupled to the memory, the method including: reading and writing data into the memory; encoding an uplink (UL) null data packet ( DP) on at least two tone sets, the at least two tone sets together encoding at least two bits, wherein: a first bit of the at least two bits is to be encoded within at least a first set of the at least two tone sets; and a subsequent bit of the at least two bits that is subsequent to the first bit is to be encoded: within a subsequent set of the at least two tone sets that is subsequent to the at least first set; and such that a value of the subsequent bit is based on a value of tones used to encode the first bit; and causing transmission of the UL NDP to an access point (AP).

[0096] Example 24 includes the subject matter of Example 23, and optionally, wherein the at least a first set consists of a first set and a second set of the at least two tone sets.

[0097] Example 25 includes the subject matter of Example 23, and optionally, wherein the first bit is to be encoded within a combination of the first set of the at least two tone sets and two rows of P-matrix.

[0098] Example 26 includes the subject matter of Example 24, and optionally, wherein the at least two tone sets consist of three tone sets, the three tone sets encoding three bits.

[0099] Example 27 includes the subject matter of Example 24, and optionally, further including setting tone values for the first set and the second set such that: to encode a first value for the first bit, a sum of powers associated with respective tones of the first set is greater than a sum of powers associated with respective tones of the second set multiplied by a predetermined decision scaling factor; and to encode a second value for the first bit, a sum of powers associated with respective tones of the second set is greater than a sum of powers associated with respective tones of the first set multiplied by a predetermined decision scaling factor.

[00100] Example 28 includes the subject matter of Example 27, and optionally, further including setting tone values for the subsequent set such that: to encode a first value for the subsequent bit, a sum of powers associated with respective tones of the subsequent set is equal to a sum of powers associated with respective tones of the first set; and to encode a second value for the subsequent bit, the sum of powers associated with tones of the subsequent set is equal to a sum of powers associated with tones of the second set.

[00101] Example 29 includes the subject matter of Example 27, and optionally, wherein the predetermined decision factor is between 1 and 5.

[00102] Example 30 includes the method of any one of Examples 23-29, and optionally, wherein the UL NDP consists of 9 RUs, each of the 9 RUs consisting of 26 tones, and each set of 26 tones being divided into 4 tone sets of 6 tones each.

[00103] Example 31 includes the method of any one of Examples 23-29, and optionally, further including decoding a trigger frame from the access point, the trigger frame including information on an encoding of the at least two bits within the at least two tone sets.

[00104] Example 32 includes the subject matter of Example 31, and optionally, wherein the information is based on at least one of: a number of tone sets that encodes the bits; a number of tone sets that encodes the first bit, a number of tone sets that encodes one or more subsequent bits, and a relationship between a value of the bits and respective sums of powers associated with tones of each respective one of the tone sets.

[00105] Example 33 includes a wireless communication device that includes a memory and a processing circuitry coupled to the memory, the device including: means for reading and writing data into the memory; means for encoding an uplink (UL) null data packet (NDP) on at least two tone sets, the at least two tone sets together encoding at least two bits, wherein: a first bit of the at least two bits is to be encoded within at least a first set of the at least two tone sets; and a subsequent bit of the at least two bits that is subsequent to the first bit is to be encoded: within a subsequent set of the at least two tone sets that is subsequent to the at least first set; and such that a value of the subsequent bit is based on a value of tones used to encode the first bit; and means for causing transmission of the UL NDP to an access point (AP).

[00106] Example 34 includes the subject matter of Example 33, and optionally, wherein the at least a first set consists of a first set and a second set of the at least two tone sets.

[00107] Example 35 includes the subject matter of Example 33, and optionally, wherein the first bit is to be encoded within a combination of the first set of the at least two tone sets and two rows of P-matrix.

[00108] Example 36 includes a wireless communication device including a memory, and a processing circuitry coupled the memory, the processing circuitry to: read data from and write data into the memory; cause transmission of a downlink (DL) multi-user (MU) multiple-input multiple output (MEVIO) trigger frame to a plurality of wireless stations (STAs); decode an uplink (UL) MU-MEVIO frame from at least some of the plurality of STAs, the UL MU-MEVIO frame including respective uplink (UL) null data packets (NDPs) from respective ones of the STAs, each UL NDP of the respective UL NDPs on at least two tone sets together encoding at least two bits; determine a value of a first bit of the at least two bits by decoding at least a first set of the at least two tone sets; and determine a value of a subsequent bit of the at least two bits that is subsequent to the first bit by decoding a subsequent set of the at least two tone sets that is subsequent to the at least first set, a value of the subsequent bit being based on a value of the first bit; and cause communication with the at least some of the plurality of STAs based on the value of the first bit and the value of the subsequent bit within said each UL NDP.

[00109] Example 37 includes the subject matter of Example 36, and optionally, wherein the at least a first set consists of a first set and a second set of the at least two tone sets.

[00110] Example 38 includes the subject matter of Example 36, and optionally, wherein the first bit is encoded within a combination of the first set of the at least two tone sets and two rows of P-matrix, decoding including performing dispreading for each of the two rows of the P- matrix.

[00111] Example 39 includes the subject matter of Example 37, and optionally, wherein the at least two tone sets consist of three tone sets, the three tone sets encoding three bits.

[00112] Example 40 includes the subject matter of Example 37, and optionally, the processing circuitry further to: determine a first value for the first bit in response to a determination that a sum of powers associated with respective tones of the first set is greater than a sum of powers associated with respective tones of the second set multiplied by a predetermined decision scaling factor; and determine a second value for the first bit in response to a determination that a sum of powers associated with respective tones of the second set is greater than a sum of powers associated with respective tones of the first set multiplied by a predetermined decision scaling factor.

[00113] Example 41 includes the subject matter of Example 40, and optionally, the processing circuitry further to: determine a first value for the subsequent bit in response to a determination that a sum of powers associated with respective tones of the subsequent set is equal to a sum of powers associated with respective tones of the first set; and determine a second value for the subsequent bit in response to a determination that the sum of powers associated with tones of the subsequent set is equal to a sum of powers associated with tones of the second set.

[00114] Example 42 includes the subject matter of Example 40, and optionally, wherein the predetermined decision factor is between 1 and 5. [00115] Example 43 includes the subject matter of any one of Examples 36-42, and optionally, wherein wherein the UL NDP consists of 9 RUs, each of the 9 RUs consisting of 26 tones, and each set of 26 tones being divided into 4 tone sets of 6 tones each.

[00116] Example 44 includes the subject matter of any one of Examples 36-42, and optionally, wherein wherein the trigger frame includes information on an encoding of the at least two bits within the at least two tone sets.

[00117] Example 45 includes the subject matter of Example 44, and optionally, wherein the information is based on at least one of: a number of tone sets that encodes the bits; a number of tone sets that encodes the first bit, a number of tone sets that encodes one or more subsequent bits, and a relationship between a value of each of the bits and respective sums of powers associated with tones of each respective one of the tone sets.

[00118] Example 46 includes the subject matter of Example 36, and optionally, further including a radio integrated circuit coupled to the processing circuitry, and a front-end module coupled to the radio integrated circuit.

[00119] Example 47 includes the subject matter of Example 46, and optionally, further including a plurality of antennas coupled to the front-end module.

[00120] Example 48 includes a product comprising one or more tangible computer- readable non-transitory storage media comprising computer-executable instructions operable to, when executed by at least one computer processor, enable the at least one computer processor to implement operations at a wireless communication device, the operations comprising: reading and writing data into a memory; causing transmission of a downlink (DL) multi-user (MU) multiple-input multiple output (MEVIO) trigger frame to a plurality of wireless stations (STAs); decoding an uplink (UL) MU-MEVIO frame from at least some of the plurality of STAs, the UL MU-MIMO frame including respective uplink (UL) null data packets (NDPs) from respective ones of the STAs, each UL NDP of the respective UL NDPs on at least two tone sets together encoding at least two bits; determining a value of a first bit of the at least two bits by decoding at least a first set of the at least two tone sets; and determining a value of a subsequent bit of the at least two bits that is subsequent to the first bit by decoding a subsequent set of the at least two tone sets that is subsequent to the at least first set, a value of the subsequent bit being based on a value of the first bit; and causing communication with the at least some of the plurality of STAs based on the value of the first bit and the value of the subsequent bit within said each UL NDP.

[00121] Example 49 includes the subject matter of Example 48, and optionally, wherein the at least a first set consists of a first set and a second set of the at least two tone sets. [00122] Example 50 includes the subject matter of Example 48, and optionally, wherein the first bit is encoded within a combination of the first set of the at least two tone sets and two rows of P-matrix, decoding including performing dispreading for each of the two rows of the P- matrix.

[00123] Example 51 includes the subject matter of Example 49, and optionally, wherein the at least two tone sets consist of three tone sets, the three tone sets encoding three bits.

[00124] Example 52 includes the subject matter of Example 49, and optionally, the operations further including: determining a first value for the first bit in response to a determination that a sum of powers associated with respective tones of the first set is greater than a sum of powers associated with respective tones of the second set multiplied by a predetermined decision scaling factor; and determining a second value for the first bit in response to a determination that a sum of powers associated with respective tones of the second set is greater than a sum of powers associated with respective tones of the first set multiplied by a predetermined decision scaling factor.

[00125] Example 53 includes the subject matter of Example 52, and optionally, the operations further including: determining a first value for the subsequent bit in response to a determination that a sum of powers associated with respective tones of the subsequent set is equal to a sum of powers associated with respective tones of the first set; and determining a second value for the subsequent bit in response to a determination that the sum of powers associated with tones of the subsequent set is equal to a sum of powers associated with tones of the second set.

[00126] Example 54 includes the subject matter of Example 52, and optionally, wherein the predetermined decision factor is between 1 and 5.

[00127] Example 55 includes the subject matter of any one of Examples 48-54, and optionally, wherein the UL DP consists of 9 RUs, each of the 9 RUs consisting of 26 tones, and each set of 26 tones being divided into 4 tone sets of 6 tones each.

[00128] Example 56 includes the subject matter of any one of Examples 48-54, and optionally, wherein the trigger frame includes information on an encoding of the at least two bits within the at least two tone sets.

[00129] Example 57 includes the subject matter of Example 56, and optionally, wherein the information is based on at least one of: a number of tone sets that encodes the bits; a number of tone sets that encodes the first bit, a number of tone sets that encodes one or more subsequent bits, and a relationship between a value of each of the bits and respective sums of powers associated with tones of each respective one of the tone sets. [00130] Example 58 includes a method to be performed at a wireless communication device that includes a memory and a processing circuitry coupled to the memory, the method including: reading and writing data into the memory; causing transmission of a downlink (DL) multi-user (MU) multiple-input multiple output (MEVIO) trigger frame to a plurality of wireless stations (STAs); decoding an uplink (UL) MU-MEVIO frame from at least some of the plurality of STAs, the UL MU-MEVIO frame including respective uplink (UL) null data packets (NDPs) from respective ones of the STAs, each UL NDP of the respective UL NDPs on at least two tone sets together encoding at least two bits; determining a value of a first bit of the at least two bits by decoding at least a first set of the at least two tone sets; determining a value of a subsequent bit of the at least two bits that is subsequent to the first bit by decoding a subsequent set of the at least two tone sets that is subsequent to the at least first set, a value of the subsequent bit being based on a value of the first bit; and causing communication with the at least some of the plurality of STAs based on the value of the first bit and the value of the subsequent bit within said each UL NDP.

[00131] Example 59 includes the subject matter of Example 58, and optionally, wherein the at least a first set consists of a first set and a second set of the at least two tone sets.

[00132] Example 60 includes the subject matter of Example 58, and optionally, wherein the first bit is encoded within a combination of the first set of the at least two tone sets and two rows of P-matrix, decoding including performing dispreading for each of the two rows of the P- matrix.

[00133] Example 61 includes the subject matter of Example 59, and optionally, wherein the at least two tone sets consist of three tone sets, the three tone sets encoding three bits.

[00134] Example 62 includes the subject matter of Example 59, and optionally, further including: determining a first value for the first bit in response to a determination that a sum of powers associated with respective tones of the first set is greater than a sum of powers associated with respective tones of the second set multiplied by a predetermined decision scaling factor; and determining a second value for the first bit in response to a determination that a sum of powers associated with respective tones of the second set is greater than a sum of powers associated with respective tones of the first set multiplied by a predetermined decision scaling factor.

[00135] Example 63 includes the subject matter of Example 62, and optionally, further including: determining a first value for the subsequent bit in response to a determination that a sum of powers associated with respective tones of the subsequent set is equal to a sum of powers associated with respective tones of the first set; and determining a second value for the subsequent bit in response to a determination that the sum of powers associated with tones of the subsequent set is equal to a sum of powers associated with tones of the second set.

[00136] Example 64 includes the subject matter of Example 59, and optionally, wherein the predetermined decision factor is between 1 and 5.

[00137] Example 65 includes the method of any one of Examples 58-64, and optionally, wherein the UL NDP consists of 9 RUs, each of the 9 RUs consisting of 26 tones, and each set of 26 tones being divided into 4 tone sets of 6 tones each.

[00138] Example 66 includes the method of any one of Examples 58-64, and optionally, wherein the trigger frame includes information on an encoding of the at least two bits within the at least two tone sets.

[00139] Example 67 includes the subject matter of Example 66, and optionally, wherein the information is based on at least one of: a number of tone sets that encodes the bits; a number of tone sets that encodes the first bit, a number of tone sets that encodes one or more subsequent bits, and a relationship between a value of each of the bits and respective sums of powers associated with tones of each respective one of the tone sets.

[00140] Example 68 includes a wireless communication device that includes a memory and a processing circuitry coupled to the memory, the device including: means for reading and writing data into the memory; means for causing transmission of a downlink (DL) multi-user (MU) multiple-input multiple output (MEVIO) trigger frame to a plurality of wireless stations (STAs); means for decoding an uplink (UL) MU-MEVIO frame from at least some of the plurality of STAs, the UL MU-MEVIO frame including respective uplink (UL) null data packets (NDPs) from respective ones of the STAs, each UL NDP of the respective UL NDPs on at least two tone sets together encoding at least two bits; means for determining a value of a first bit of the at least two bits by decoding at least a first set of the at least two tone sets; and means for determining a value of a subsequent bit of the at least two bits that is subsequent to the first bit by decoding a subsequent set of the at least two tone sets that is subsequent to the at least first set, a value of the subsequent bit being based on a value of the first bit; and means for causing communication with the at least some of the plurality of STAs based on the value of the first bit and the value of the subsequent bit within said each UL NDP.

[00141] Example 69 includes the subject matter of Example 68, and optionally, wherein the at least a first set consists of a first set and a second set of the at least two tone sets.

[00142] Example 70 includes the subject matter of Example 68, and optionally, wherein the first bit is encoded within a combination of the first set of the at least two tone sets and two rows of P-matrix, decoding including performing dispreading for each of the two rows of the P- matrix.