Abstract: This disclosure provides methods, devices and systems for generating a secure long training field (LTF). In some implementations, the secure LTF may include a randomized bit sequence that is difficult, if not impossible, to replicate by any device other than the transmitting device and the intended receiving device. For example, the transmitting device may use a block cipher or stream cipher to generate a pseudorandom bit sequence and may select a subset of bits of the pseudorandom bit sequence to be mapped to a sequence of modulation symbols representing an LTF symbol of the secure LTF. More specifically, each of the modulation symbols is mapped to a respective one of a number of subcarriers spanning a bandwidth of the secure LTF. The transmitting device may further transmit a physical layer convergence protocol (PLCP) protocol data unit (PPDU) that includes the secure LTF to the receiving device.

Abstract: Methods, systems, and devices for wireless communications are described. An access point (AP) may identify a sequence of on symbols and off symbols for transmission to a wake-up radio (WUR) of a wireless device. The AP may assign a modulation symbol from a set of possible modulation symbol waveforms to at least each on symbol in the sequence. The modulation symbol waveforms may be assigned to sequential on symbols in a random or pseudorandom order, e.g., by applying a random phase rotation to a stored modulation symbol waveform, by applying a random cyclic shift to a stored modulation symbol waveform, or by applying a random or pseudorandom phase-shift keying value to each subcarrier in a multicarrier system to generate a modulation symbol waveform. The AP may transmit the sequence to the WUR based at least in part on the assigned modulation symbol waveforms.

Abstract: This disclosure provides methods, devices and systems for wireless communication, and particularly, methods, devices and systems for generating or receiving a wireless packet that includes a first preamble based on a first generation of a wireless communication protocol and a second preamble based on a second generation of the wireless communication protocol. The wireless packet may include the first preamble in a first subchannel of a wireless channel and the second preamble in a second subchannel of the wireless channel. Thus, the wireless packet may concurrently include communication to or from different types of wireless stations that support the different generations of a wireless communication protocol.

Abstract: This disclosure provides systems, methods, and apparatus, including computer programs encoded on computer-readable media, for implementing a hybrid automatic repeat request (HARQ) protocol in a wireless local area network (WLAN). A first WLAN device may generate a first HARQ packet for transmission to a second WLAN device. The first WLAN device may determine a first basic service set (BSS) indicator and a second BSS indicator for a BSS associated with the first WLAN device and the second WLAN device. The first BSS indicator and the second BSS indicator may be indicative of a BSS identifier (BSSID) of the BSS. The first WLAN device may output the first HARQ packet for transmission to the second WLAN device. The first HARQ packet may include the first BSS indicator and the second BSS indicator in one or more fields of a physical layer (PHY) header of the first HARQ packet.

Abstract: This disclosure provides systems, methods and apparatus, including computer programs encoded on computer storage media, for low density parity check (LDPC)-based incremental redundancy (IR) hybrid automatic repeat request (HARQ) transmission processing. In one aspect, an apparatus for wireless communications is configured to generate a first packet using a LDPC encoding process. The apparatus is further configured to generate coded bits using a second LDPC encoding process if the first packet is not successfully decoded by a wireless device, generate a second packet including at least some of the coded bits generated using the second LDPC encoding process, and output the second packet for transmission.

Abstract: This disclosure provides methods, devices and systems for wireless communication, and particularly, methods, devices and systems for physical (PHY) layer control signaling. A first physical layer convergence protocol (PLCP) protocol data unit (PPDU) may precede a second PPDU. The first PPDU may be referred to as a PHY control PPDU and may include a physical layer control signaling field (CNT-SIG) that informs one or more stations (STAs) regarding a physical layer configuration they should use for the second PPDU. The PHY control PPDU may enable dynamic subchannel assignments for one or more identified STAs, legacy STAs, or sub-bandwidth operating devices. The techniques of this disclosure may enable sharing of a wide bandwidth wireless channel by different types of devices or different basic service sets (BSSs) assigned to different subchannels of the wireless channel.

Abstract: This disclosure provides methods, devices and systems for identifying wake-up signals. Some implementations more specifically relate to PHY preamble designs for wake-up signals such as Wake-Up Radio (WUR) packets conforming to IEEE 802.11ba. In some implementations, the preamble designs can include a combination of modulation schemes, data rate indications and length indications enabling devices capable of receiving and decoding wake-up signals to identify the signals as wake-up signals (for example, WUR packets), while ensuring that devices not capable of receiving and decoding wake-up signals identify the wake-up signals as legacy packets, or otherwise not WUR packets.

Abstract: This disclosure provides methods, devices and systems for encoding data in wireless communications. Some implementations more specifically relate to performing a first encoding operation on data bits of a code block to shape the amplitudes of the resultant symbols such that the amplitudes have a non-uniform distribution. In some aspects, the probabilities associated with the respective amplitudes generally increase with decreasing amplitude. For example, the non-uniform distribution of the amplitudes of the symbols may be approximately Gaussian. In some aspects, the first encoding operation is or includes a prefix encoding operation having an effective coding rate greater than 0.94 but less than 1. The first encoding operation is followed by a second encoding operation that also adds redundancy but does not alter the data bits themselves. In some aspects, the second encoding operation is or includes a low-density parity-check (LDPC) encoding operation associated with a coding rate greater than 5/6.

Abstract: Methods, systems, and devices for wireless communication are described. An access point (AP) may identify a jitter pattern for a wakeup message. A station may listen using a wakeup radio for a wakeup message during wakeup listening periods according to the identified jitter pattern. A station may receive a preamble having a first bandwidth and a wakeup message having a second bandwidth. An AP may transmit an identifier key to a station, and the station may determine a rotating identifier associated with the AP based on the received identifier key. The station may receive a wakeup message from the AP, compare a sender identifier with the rotating identifier, and power on a second radio. A station may also receive a wakeup message that includes an indication of which station are to be activated.

Abstract: This disclosure provides systems, methods, and apparatus, including computer programs encoded on computer-readable media, for a link adaptation protocol in a wireless local area network (WLAN). In one aspect, the link adaptation protocol may be used to select a transmission rate option (such as a modulation and coding scheme (MCS)) for communications from a first WLAN device to a second WLAN device based on wireless channel conditions. This disclosure includes several example message sequences for the link adaptation protocol which can accommodate a variety of uplink or downlink data transmission designs, including single user (SU) and multi-user (MU) transmissions. The example message sequences may be used with orthogonal frequency division multiple access (OFDMA), multiple-input-multiple-output (MIMO), and beamformed transmissions.

Abstract: This disclosure provides systems, methods, and apparatus for link adaptation in a wireless local area network (WLAN). A link adaptation test packet from a first WLAN device to a second WLAN device may be formatted as a multiple-input-multiple-output (MIMO) transmission and may include one or more test portions for link quality estimation of the MIMO transmission. A link quality estimation portion of the test packet may permit measurement of link quality for various spatial streams of the MIMO transmission. The link adaptation test packet may enable a fast rate adaptation of a communication link based on the impact of interference to the various spatial streams. The second WLAN device may provide feedback information regarding the one or more test portions. The feedback information may be used to determine a transmission rate for a subsequent transmission from the first WLAN device to the second WLAN device based on wireless channel conditions.

Abstract: This disclosure provides systems, methods, and apparatus, including computer programs encoded on computer-readable media, for link adaptation in a wireless local area network (WLAN). A link adaptation test packet from a first WLAN device to a second WLAN may include a plurality of link adaptation test portions that are generated using a corresponding plurality of transmission rate options. For example, the plurality of link adaptation test portions may be modulated using different modulation and coding scheme (MCS) options. Thus, a single test packet may be used to evaluate different transmission rate options. The second WLAN device may provide feedback information regarding the link adaptation test portions. The feedback information may be used to determine a transmission rate for a subsequent transmission from the first WLAN device to the second WLAN device based on wireless channel conditions.

Abstract: This disclosure provides systems, methods and apparatus, including computer programs encoded on computer storage media, for establishing communications with one or more devices. In one aspect, a first device generates a wake-up radio (WUR) frame, the WUR frame including a media access control (MAC) header and a frame check sequence (FCS) having a cyclic redundancy check (CRC) or a message integrity check (MIC). The first device may determine the FCS based, at least in part, on the MAC header and basic service set identifier (BSSID) information associated with the first device. The first device may output the WUR frame for transmission to one or more devices. A second device may receive the WUR frame from the first device and determine whether the WUR frame is directed to the second device based, at least in part, on comparing the FCS of the WUR frame with a calculated FCS.

Abstract: This disclosure provides methods, devices and systems for link adaptation in wireless communications. Some implementations more specifically relate to transmitter-based modulation and coding scheme (MCS) selection. A transmitting device transmits a test packet, over a wireless channel, to a receiving device. The receiving device generates one or more signal-to-interference-plus-noise ratio (SINR) estimates for the wireless channel based on the received sounding packet. In some aspects, each SINR estimate may be associated with a particular modulation order. In some other aspects, each SINR estimate may be generated based on a transmitter configuration or a receiver type to be used for subsequent communications between the transmitting device and the receiving device. The receiving device transmits feedback, including the SINR estimates, to the transmitting device.

Abstract: This disclosure provides systems, methods, and apparatus, including computer programs encoded on computer-readable media, for priority access on a shared wireless channel. A priority station (STA), an access point (AP), or a network operator may activate a priority access service. The priority access service provides priority access to authorize priority STAs by allowing them to use more aggressive contention parameters for contention-based access of the wireless channel as compared to other STAs. In some implementations, non-priority STAs may be configured with weakened contention parameters to increase or ensure the likelihood that a priority STA will win contention for access to the wireless channel.

Abstract: This disclosure provides systems, methods, and apparatus, including computer programs encoded on computer-readable media, for implementing a hybrid automatic repeat request (HARQ) protocol in a wireless local area network (WLAN). A first WLAN device may generate a first HARQ packet for transmission to a second WLAN device. The first WLAN device may determine a first basic service set (BSS) indicator and a second BSS indicator for a BSS associated with the first WLAN device and the second WLAN device. The first BSS indicator and the second BSS indicator may be indicative of a BSS identifier (BSSID) of the BSS. The first WLAN device may output the first HARQ packet for transmission to the second WLAN device. The first HARQ packet may include the first BSS indicator and the second BSS indicator in one or more fields of a physical layer (PHY) header of the first HARQ packet.

Abstract: This disclosure provides systems, methods, and apparatus, including computer programs encoded on computer-readable media, for implementing a hybrid automatic repeat request (HARQ) protocol in a wireless local area network (WLAN). A station (STA) may send a HARQ transmission to another STA. The HARQ protocol may support the use of different types of feedback from the receiving STA to control the HARQ retransmission process. This disclosure provides example message formats to support HARQ transmission and HARQ feedback in a WLAN.

Abstract: This disclosure provides methods, devices and systems for wireless communication, and particularly, methods, devices and systems for implementing a joint transmission feature in a wireless communication system. Using the joint transmission feature, multiple access points (APs) may use an aggregated collection of antennas of multiple APs to simultaneously transmit a joint beamformed transmission to one or more stations (STAs). The techniques in this disclosure may prevent or reduce variations in relative gain adjustments by the APs that could otherwise negatively impact the joint transmission. In some implementations, a network device may determine a normalized gain adjustment value based on power parameters associated with each of the multiple APs. In some other implementations, each AP may determine the normalized gain adjustment value based on power parameters shared between the APs.

Abstract: This disclosure provides systems, methods, and apparatus, including computer programs encoded on computer-readable media, for implementing a hybrid automatic repeat request (HARQ) protocol in a wireless local area network (WLAN). A first WLAN device may transmit a first HARQ frame to a second WLAN device. The first HARQ frame may include initial transmissions of a first plurality of forward error correction (FEC) codewords. The HARQ protocol may support new techniques for feedback, such as a feedback capability in which a bitmap may be used to indicate decoding failures of codewords. The first feedback message may include indicators to change a HARQ configuration parameter based on channel conditions. In some implementations, the second HARQ frame may combine retransmissions regarding the failed codewords with initial transmissions of a second plurality of codewords.

Abstract: This disclosure provides systems, methods and apparatuses for indicating a data rate of a packet. The transmitting device may select the data rate of a data field of the packet to be transmitted to the receiving device, and may select a pattern to embed within a preamble of the packet based on the selected data rate. In some implementations, the transmitting device may select a first structure including a first number of instances of a sequence or its logical complement if the selected data rate is a low data rate, and may select a second structure including a second number of instances of the sequence or its logical complement if the selected data rate is a high data rate.