Cisco Technology, Inc.

Jiunming Huang

Brian Donald Hart

Matthew Aaron Silverman

Mithat C Dogan

David Stuart Kloper

Glendon Leo Akins, Iii

Paul Jeffrey Stager

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.

Computing transmit and receive filters for a network device

Techniques are disclosed to reduce latency of processing for access points using a central controller. For example, an example method of wireless communication includes receiving, at an access point, a signal wirelessly. The method further includes filtering the signal using a first passband filter having a first bandwidth to generate a first filtered signal. The method further includes filtering the signal using a second passband filter having a second bandwidth to generate a second filtered signal, wherein the first bandwidth is less than the second bandwidth. The method further includes determining whether the signal includes a packet based on the first filtered signal and generating a control signal indicative of the determination. The method further includes transmitting the control signal and the second filtered signal to a central controller.

Processing of wireless signals for access points using a central controller

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.

Updating precoding matrix for MIMO transmissions

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.

Remote radio head reciprocity calibration

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. In one embodiment, at least one of the radio heads is isolated from 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.

Growing community of inventors

San Jose, CA, United States of America

Jiunming Huang