Abstract:
A system and method are provided for performing stomp-and-restart techniques in distributed MU-MIMO system. A plurality of radio head devices are provided that are configured to be deployed separated from each other in a coverage region of interest of a wireless network. A central processor subsystem is provided that is in communication with the plurality of radio head devices. The central processor subsystem configured to perform several operations based on downconverted samples received from the plurality of radio head devices.
Abstract:
A wireless access point device wirelessly communicates with a plurality of wireless client devices. The wireless access point includes a central processor subsystem and a plurality of transceiver devices each including a plurality of antennas, and a plurality of radio transceivers, each of the plurality of transceiver devices configured for deployment throughout a coverage area, each transceiver device being connected to the central processor subsystem via a respective cable. The central processor subsystem distributes in-phase and quadrature baseband samples across the plurality of transceiver devices associated with traffic to be transmitted and received via the plurality of transceiver devices in one or more frequency bands so as to synthesize a wideband multiple-input multiple-output transmission channel and a wideband multiple-input multiple-output reception channel. The access point transmit and receive functions are “split” or partitioned across the plurality of transceivers devices.
Abstract:
Techniques are presented herein for improving location determination of a wireless device in environments where there can be multipath issues. A wireless device having a plurality of antennas receives a wireless transmission from a target device whose location is to be determined. Channel state information data is generated based on reception of the transmission at the plurality of antenna. The channel state information data is separated or partitioned into subcarrier group specific data for each of a plurality of groups of subcarriers within a bandwidth of the received transmission. Location probability data is computed for each of the plurality of groups of subcarriers from the subcarrier group specific data for respective ones of the plurality of groups of subcarriers. The location probability data for the plurality of groups of subcarriers is combined to produce aggregate location probability data, from which a location of the target device is determined.
Abstract:
A method is provided in which a first wireless access point selects two or more of a plurality of client devices based on similarity of receive signal strength and carrier frequency offset with respect to the first wireless access point, and sends a downlink multi-user multiple-input multiple-output (MIMO) transmission to the two or more client devices. The downlink multi-user MIMO transmission is configured to solicit acknowledgments from the two or more client devices. The acknowledgments are received at a plurality of antennas of the first wireless access point from the two or more client devices. Uplink multi-user MIMO processing of the acknowledgments is performed from the two or more of the plurality of client devices to recover the acknowledgments respectively from each of the two or more client devices.
Abstract:
A pair of Clear Channel Assessment (CCA) rules are presented that protect an initiator's transmission at the responder, and the responder's transmission at the initiator, using additional fields transmitted in a preamble (header) of a Physical Layer Convergence Procedure (PLCP) Protocol Data Unit (PPDU) or in a Media Access Control (MAC) header, if unencrypted and robustly modulated. These techniques enable more parallel/simultaneous transmissions between devices that might otherwise interfere with each other, subject to ensuring an adequate Signal-to-Interference and-Noise Ratio (SINR) for the initiator's transmission at the responder and ensuring an adequate SINR for the responder's transmission at the initiator.
Abstract:
In accordance with an embodiment, a method is provided in which a first wireless access point sends a downlink multi-user multiple-input multiple-output (MIMO) transmission to a plurality of client devices. The downlink multi-user MIMO transmission is configured to solicit acknowledgments from two or more of the plurality of client devices. The acknowledgments are received at a plurality of antennas of the first wireless access point from the two or more of the plurality of client devices. Uplink multi-user MIMO processing of the acknowledgments is performed from the two or more of the plurality of client devices to recover the acknowledgments respectively from each of the two or more of the plurality of client devices.
Abstract:
A computing entity, such as a server, obtains a first, second, and third set of measurements based on wireless transmissions between one or more beacon devices, a wireless client device, and one or more wireless access points in a wireless network. The first set of measurements is associated with wireless transmissions from the beacon device(s) received at the wireless access points. The second set of measurements is associated with wireless transmissions between the wireless client device and the wireless access points. The third set of measurements is associated with wireless transmissions from beacon devices received at the wireless client device. An estimated location of the wireless client device is generated based on the first set of measurement data, the second set of measurement data, and the third set of measurement data.
Abstract:
Wireless transmissions from beacon devices are received at a plurality of receiver devices. The wireless transmissions comprise packets that carry information used for location-based services for mobile wireless devices. Content of one or more fields of the beacon packets received by one or more of the plurality of receiver devices is obtained. Measurement data associated with the transmissions received at the plurality of receiver devices is generated. Locations of the respective beacon devices are computed from the measurement data obtained by the plurality of receiver devices. Information identifying detected beacon devices and their locations are stored to maintain a location history of beacon devices over time locations. Changes from information contained in the location history are detected based on the locations computed for respective beacon devices from the measurement data and content of one or more fields of detected beacon packets.
Abstract:
Techniques are provided herein to allow a wireless network access point (AP) to more fully use its bandwidth in order to leverage the different bandwidth capabilities of different types of wireless client devices that the AP serves. The AP generates control parameters for usage of a plurality of channels in a bandwidth during a downlink transmission interval. The control parameters comprise information indicating channel assignments that result in multiple downlink transmissions that at least partially overlap in time to different wireless client devices according to their respective bandwidth capabilities. The AP transmits the control parameters in a control frame in advance of the downlink transmission interval on each of the plurality of channels in the bandwidth.
Abstract:
Techniques are presented herein for improving location determination of a wireless device in environments where there can be multipath issues. A wireless device having a plurality of antennas receives a wireless transmission from a target device whose location is to be determined. Channel state information data is generated based on reception of the transmission at the plurality of antenna. The channel state information data is separated or partitioned into subcarrier group specific data for each of a plurality of groups of subcarriers within a bandwidth of the received transmission. Location probability data is computed for each of the plurality of groups of subcarriers from the subcarrier group specific data for respective ones of the plurality of groups of subcarriers. The location probability data for the plurality of groups of subcarriers is combined to produce aggregate location probability data, from which a location of the target device is determined.