Abstract:
Aspects of the present disclosure may compensate for cyclic shift delays (CSD) in transmitted signals when estimating angle of arrival information of a wireless signal transmitted by a transmitting device. In some aspects, a receiving device may determine a presence of CSD in the wireless signal, and estimate an angle of arrival of the wireless signal based at least in part on the presence of CSD. For example, the receiving device may determine a first tap of the wireless channel based at least in part on the CSD. The receiving device may then determine a phase difference of the wireless signal between a plurality of antennas of the receiving device based on the first tap of the wireless channel. The receiving device may estimate the angle of arrival of the wireless signal based on the phase difference.
Abstract:
Techniques for estimating a position of an observing station are disclosed based on capturing, at the observing station, a first and a second FTM message exchanged between a first messaging station and a second messaging station. At the observing station, a first time of arrival of the first FTM message and a second time of arrival of the second FTM message may be determined. Based on contents of one or more FTM messages, a first transmission-related time associated with the first FTM message and a second transmission-related time associated with the second FTM message may be obtained. The position of the observing station may be estimated based on (1) a position of the first messaging station, (2) a position of the second messaging station, (3) the first time of arrival, (4) the second time of arrival, (5) the first transmission-related time, and (6) the second transmission-related time.
Abstract:
Disclosed embodiments pertain to a first STA may broadcast a first Null Data Packet Announcement (NDPA) frame with an indication of one or more second STAs being polled. Subsequent to the first NDPA frame, a Null Data Packet (NDP) frame may be broadcast from a plurality of antennas on the first STA and one or more corresponding first Fine Timing Measurement (FTM) frames may be received in response. Each corresponding first FTM frame may be received from a distinct corresponding second STA and may comprise corresponding ranging measurements between the first STA and the corresponding second STA as determined by the corresponding second STA based on the NDP frame. In some embodiments, the one or more corresponding first FTM frames may be: received in response to a previously broadcast trigger frame, and encoded using Orthogonal Frequency Division Multiple Access. The trigger frame may be broadcast subsequent to the NDP frame.
Abstract:
Aspects of the present disclosure may compensate for a presence of phase ambiguity between transmit chains of a transmitting device when estimating angle of departure information of a wireless signal transmitted from the transmitting device. In some aspects, a receiving device may determine phase information of the wireless signal, and then determine whether there is a presence or absence of phase ambiguity between a number of transmit chains of the transmitting device. If there is presence of phase ambiguity in the transmitting device, then the receiving device may adjust the phase information of the received wireless signal. If there is an absence of phase ambiguity in the transmitting device, then the receiving device may not adjust the phase information. Thereafter, the receiving device may estimate the angle of departure of the wireless signal based on the selectively adjusted phase information.
Abstract:
Methods, systems, and devices are described for wireless communication at a device. A Long Term Evolution Unlicensed (LTE-U) device may transmit an enhanced preamble that may be understood by Wireless Local Area Network (WLAN) devices, in addition to conveying a characteristic that is detectable by receiving LTE-U devices. The transmitting LTE-U device may generate the enhanced preamble by generating a first training field and a second training field. The characteristic that is detectable by receiving LTE-U devices may be a phase shift between the first and second training fields. Additionally or alternatively, the characteristic may be a sequence or tone mapping of the first or second training field. In some cases, the transmitting LTE-U device may introduce a third training field to the preamble which serves as the characteristic.
Abstract:
Certain aspects of the present disclosure relate to a methods and apparatus for wireless communication. In one aspect, a method of communication over a wireless medium includes transmitting, from a first wireless device, a first communication reserving access to the wireless medium during a first time period. The method further includes transmitting or receiving a long term evolution unlicensed (LTE-U) transmission during the first time period. The method further includes detecting, prior to the first time period, an interfering WLAN transmission that will result in its transmitter and recipients not detecting the first communication. The method further includes transmitting, after the interfering WLAN transmission, a second communication reserving access to the wireless medium during a second time period at least partially overlapping the first.
Abstract:
A system and method are disclosed that may provide an accurate estimate of an AP's available medium share. The AP may perform a plurality medium access contention operations to determine a duration of a transmit opportunity and a queue service interval for each of a plurality of access categories. The AP may also determine a queue service interval for a number of packet queues associated with each of the access categories. The AP may use timing information derived from the medium access contention operations to estimate a portion of the medium share available on a per-access category and/or per-user basis. The timing information may include the transmit opportunity durations and queue service intervals for the access categories, the queue service intervals for the individual packet queues, and/or values indicative of the AP's PHY rate and medium utilization.
Abstract:
Methods, systems, and devices for wireless communications are described. Some wireless communications systems may support adaptation of digital pre-distortion (DPD) coefficients based on a temperature of a user equipment (UE). The UE may determine a power offset value based on a first temperature value associated with a training procedure for the UE, a second temperature value associated with the UE, and a constant value. The training procedure may be associated with multiple sets of coefficients for the UE. The UE may apply the power offset value to a transmission power level for transmission of a message. The UE may determine a set of coefficients of the multiple sets of coefficients based on the training procedure and the power offset value applied to the transmission power level. The UE may apply the coefficients to a DPD engine of the UE to generate the message for transmission at the transmission power level.
Abstract:
Methods, systems, and devices for wireless communications are described. Some wireless communications systems may support adaptation of digital pre-distortion (DPD) coefficients based on a temperature of a user equipment (UE). The UE may determine a power offset value based on a first temperature value associated with a training procedure for the UE, a second temperature value associated with the UE, and a constant value. The training procedure may be associated with multiple sets of coefficients for the UE. The UE may apply the power offset value to a transmission power level for transmission of a message. The UE may determine a set of coefficients of the multiple sets of coefficients based on the training procedure and the power offset value applied to the transmission power level. The UE may apply the coefficients to a DPD engine of the UE to generate the message for transmission at the transmission power level.
Abstract:
Methods, apparatuses, and computer-readable medium for DPD are provided. An example method may include receiving, from a base station, an uplink grant associated with one or more resources. The example method may further include transmitting, to the UE via the one or more resources, a DPD training signal at a first port of a plurality of ports. The example method may further include receiving, at a second port of the plurality of ports, the DPD training signal.