Abstract: Techniques are presented herein for computing angle-of-arrival estimates while switching antenna states during a packet unit for the general Orthogonal Frequency Division Multiple Access (OFMDA) case (including a single user). A wireless device computes channel estimates throughout the entire frame and not only during the training symbols. Consequently, the wireless device computes channel estimates for all antennas in its array within a single frame instead of having to wait for multiple frames.

Abstract: The embodiments herein use a factorization based technique for determining filter coefficients for a subset of the subcarriers in a wireless frequency band. Once the filter coefficients for the subset of the subcarriers are calculated, the network device uses these filter coefficients to identify the filter coefficients in a neighboring subcarrier. To do so, the network device uses pseudo-inverse iteration to convert the already calculated filter coefficients into filter coefficients for a neighboring subcarrier. The network device can repeat this process for the next set of neighboring subcarriers until all the filter coefficients have been calculated.

Abstract: The present disclosure discloses that a device uses precoding to transmit independent data streams to existing users and additional independent data streams to one or more new users simultaneously. During a first transmission of a first one or more data streams that are precoded using a first precoding matrix, the device determines to transmit a second one or more data streams in a second transmission. Before the first transmission is complete, the device calculates a combined precoding matrix for precoding the first one or more data streams and the second one or more data streams. The device transmits the first one or more data streams in the first transmission and the second one or more data streams in the second transmission simultaneously using the combined precoding matrix.

Abstract: An apparatus comprises an antenna array, a block of switches, a programmable logic device and a memory device. The antenna array comprises a plurality of antenna elements. The block of switches is configured to selectively connect respective ones of a subset of the plurality of antenna elements to corresponding ones of a plurality of transceivers in a host device. The programmable logic device is configured to communicate with the host device and to control the block of switches. The memory device is coupled to the programmable logic device, and is configured to store information allowing the host device to determine how to control connectivity of individual antenna elements to respective ones of the plurality of transceivers of the host device as part of transmit and/or receive operations of the host device.

Abstract: Techniques for channelization of a wireless communication network in the presence of interference are described. In one embodiment, a method includes detecting an unlicensed wireless wide area network signal. The method includes selecting a wireless channel for a wireless local area network that includes frequencies associated with the unlicensed signal. The method includes allocating a first portion of the wireless channel that includes frequencies associated with the unlicensed signal to a first plurality of resource units and allocating a second portion of the wireless channel that excludes frequencies associated with the unlicensed signal to a second plurality of resource units. The method includes assigning the first plurality of resource units to a first group of client devices, and assigning the second plurality of resource units to a second group of client devices.

Abstract: Receiving filter design that reduces out-of-channel interference for APs is disclosed. An AP includes a first radio and a second radio disposed in a body of the AP. The first radio transmits first signals in a frequency band while the second radio receives second signals in the same frequency band. The AP includes an interference mitigation controller that determines a receiving filter for the second radio to mitigate interference between the first radio and the second radio based on the second signals received by the second radio when the first radio transmits the first signals in the frequency band. The interference mitigation controller applies the receiving filter to signals received by the second radio during a time period that the first radio is transmitting signals in the frequency band while the second radio is receiving signals in the frequency band.

Abstract: Techniques are presented herein for computing angle-of-arrival estimates while switching antenna states during a packet unit for the general Orthogonal Frequency Division Multiple Access (OFMDA) case (including a single user). A wireless device computes channel estimates throughout the entire frame and not only during the training symbols. Consequently, the wireless device computes channel estimates for all antennas in its array within a single frame instead of having to wait for multiple frames.

Abstract: Embodiments herein describe calibrating a plurality of radio heads having a plurality of wireless antennas. In one embodiment, the plurality of radio heads communicate a calibration signal in a round robin fashion such that each of the radio heads communicates a respective calibration signal to the remaining radio heads. The received calibration signals are then used to calibrate the radio heads. In one embodiment, a controller coupled with the plurality of radio heads calibrates the radio heads. The calibrated radio heads then communicate to one or more client devices.

Abstract: A central processor subsystem controls multiple transceivers. Each transceiver transmits protocol data units from antennas of that transceiver and produces receive waveforms from wirelessly received signals at the one or more antennas. A transmit waveform, including a frame addressed to one or more wireless client devices, is sent through a first transceiver to be transmitted wirelessly by the first transceiver on a frequency channel. A receive waveform, representative of the transmission by the first transceiver and wirelessly received at a second transceiver, is received from the second transceiver. While the transmit waveform is being sent to the first transceiver: a level of collision between the receive waveform and another transmission on the frequency channel is detected; and if the level of collision exceeds a threshold prior to an end of the receive waveform, the transmit waveform being sent to the first transceiver is modified to reduce the collision.

Abstract: A wireless device, such as an wireless access point, receives signals detected by a plurality of antennas of a wireless device to produce a plurality of antenna-specific receive signals potentially representing a wireless transmission received from each of one or a plurality of devices. A signal processing component of the wireless device, such as a modem, performs several operations on the antenna-specific receive signals, including building a first space-time equalizer to be applied to the plurality of antenna-specific receive signals to recover a transmission from a first device by both equalizing channel effects and canceling out effects associated with transmissions from devices other than the first device, and building a second space-time equalizer to be applied to the plurality of antenna-specific receive signals to recover a transmission from a second device by both equalizing channel effects and canceling out effects associated with transmissions from devices other than the second device.

Abstract: Techniques are presented herein for computing angle-of-arrival estimates while switching antenna states during a packet unit for the general Orthogonal Frequency Division Multiple Access (OFMDA) case (including a single user). A wireless device computes channel estimates throughout the entire frame and not only during the training symbols. Consequently, the wireless device computes channel estimates for all antennas in its array within a single frame instead of having to wait for multiple frames.

Abstract: Techniques are disclosed to synchronize wireless signal transmission by endpoints controlled by a central controller. For example, an example method of wireless communication includes receiving, at a first device, over a wired medium between the first device and a second device, a plurality of packets from the second device. Each of the plurality of packets comprises data representative of a portion of a signal corresponding to a wireless medium. The method further includes receiving, at the first device, from the second device over the wired medium a synchronization signal based on a common master clock at the second device. The method further includes synchronizing, at the first device, a local clock of the first device to the common master clock based on the synchronization signal. The method further includes reconstructing the signal corresponding to the wireless medium based on the plurality of packets and the synchronized local clock.

Abstract: A wireless device, such as an wireless access point, receives signals detected by a plurality of antennas of a wireless device to produce a plurality of antenna-specific receive signals potentially representing a wireless transmission received from each of one or a plurality of devices. A signal processing component of the wireless device, such as a modem, performs several operations on the antenna-specific receive signals, including building a first space-time equalizer to be applied to the plurality of antenna-specific receive signals to recover a transmission from a first device by both equalizing channel effects and canceling out effects associated with transmissions from devices other than the first device, and building a second space-time equalizer to be applied to the plurality of antenna-specific receive signals to recover a transmission from a second device by both equalizing channel effects and canceling out effects associated with transmissions from devices other than the second device.

Abstract: A plurality of first wireless devices monitor a ranging exchange of transmissions between a target wireless device and a second wireless device in order to record for each of the plurality of first wireless devices a time of reception of a first transmission that is sent from the second wireless device to the target wireless device and a time of reception of a second transmission that is sent from the target wireless device to the second wireless device. Using a timing error computed from the estimated location, a modification is made of the time of transmission of the first transmission to produce a first modified timestamp and of the time of reception of the second transmission to produce a second modified timestamp. A ranging measurement is computed of the target wireless device relative to the second wireless device using the first modified timestamp and the second modified timestamp.

Abstract: The embodiments herein use a factorization based technique for determining filter coefficients for a subset of the subcarriers in a wireless frequency band. Once the filter coefficients for the subset of the subcarriers are calculated, the network device uses these filter coefficients to identify the filter coefficients in a neighboring subcarrier. To do so, the network device uses pseudo-inverse iteration to convert the already calculated filter coefficients into filter coefficients for a neighboring subcarrier. The network device can repeat this process for the next set of neighboring subcarriers until all the filter coefficients have been calculated.

Abstract: Presented herein are techniques to ensure power emitted by APs during a cooperative MIMO transmission is within certain limits. For a transmission to be made from two or more wireless access points using cooperative multiple-input multiple-output (MIMO) techniques, a measure of separation is determined between the two or more access points. Precoding of signals to be transmitted by the two or more access points is adjusted so as to derate the signals to be transmitted or disable the cooperative nature of the transmission from the two or more access point depending on the measure of separation so that a combined output power from the two or more access points is within a limit.

Abstract: Presented herein are techniques to ensure power emitted by APs during a cooperative MIMO transmission is within certain limits. For a transmission to be made from two or more wireless access points using cooperative multiple-input multiple-output (MIMO) techniques, a measure of separation is determined between the two or more access points. Precoding of signals to be transmitted by the two or more access points is adjusted so as to derate the signals to be transmitted or disable the cooperative nature of the transmission from the two or more access point depending on the measure of separation so that a combined output power from the two or more access points is within a limit.

Abstract: Embodiments herein describe a network device (e.g., an access point) that dynamically arranges multi-user (MU) multiple input multiple output (MIMO) compatible client devices into MU-MIMO groups. That is, the network device uses network metrics and historical data to change the assignment of client devices in the MU-MIMO groups which may improve MU-MIMO efficiency by reducing the amount of power that leaks between the clients devices in the group. In one embodiment, the AP identifies a MU-MIMO group based on a performance evaluation such as evaluating network metric or determining if the group is underutilized. The AP can replace the identified MU-MIMO group with a substitute MU-MIMO group where the substitute MU-MIMO group is selected based on historical data corresponding to the client devices assigned to the substitute MU-MIMO group.

Abstract: A third device stores a receive signal strength of a received response data unit transmitted by a second device after receiving a first data unit transmitted by a first device. The third device obtains a clear channel access parameter included in a header of a second data unit transmitted by the first device to the second device and detects transmission exchanges in each of a plurality of service sets to use as samples of overlapping service set activity. The third device determines a minimum transmit power to be used by the third device to send a transmission to the fourth device based on transmission exchanges between devices in a particular service set. The third device determines whether to send a transmission to the fourth device based on the clear channel access parameter and minimum transmit power.

Abstract: A central processor subsystem controls multiple transceivers. Each transceiver transmits protocol data units from antennas of that transceiver and produces receive waveforms from wirelessly received signals at the one or more antennas. A transmit waveform, including a frame addressed to one or more wireless client devices, is sent through a first transceiver to be transmitted wirelessly by the first transceiver on a frequency channel. A receive waveform, representative of the transmission by the first transceiver and wirelessly received at a second transceiver, is received from the second transceiver. While the transmit waveform is being sent to the first transceiver: a level of collision between the receive waveform and another transmission on the frequency channel is detected; and if the level of collision exceeds a threshold prior to an end of the receive waveform, the transmit waveform being sent to the first transceiver is modified to reduce the collision.