Abstract: To reduce the duration of a cyclic prefix used for a multiple input, multiple output (MIMO) communications channel, delay spread variations for different transmit/receive beam pair combination is estimated and used for fast beam switching and to support single user MIMO (SU-MIMO) even when the CP difference between two beams is large. Beam switching reference signals are employed to estimate delay spread exceeding current CP, and to support beam switching. CP covering sub-clusters within clusters for the MIMO channel are exploited to reduce the CP requirement and improve efficiency. Any one of a number of different CP durations may be selected for each different mobile station, using one of a finite set of subframe configurations for which the CP durations of different symbol locations within the subframe are predefined. Dynamically switching subframe configurations by the system accommodates high mobility.

Abstract: A transmit resonator includes at least two loop resonators, disposed in such that the magnetic field produced by each in the near-field zone is substantially orthogonal to that produced by the other at a certain or specific portion of the zone, a power divider configured to split a signal into at least two sub-signals with weighting coefficients, a delay array configured to delay the at least one of the sub-signals and feed each of the sub-signals to each of the loop resonators, and a controller to configure the delay array to control the polarization of the near zone magnetic field. A communication module to receive feedback information from a receiver, to determine the phases of at least two sub-signals to generate a near zone magnetic field optimized for the receiver.

Abstract: One embodiment of the present invention is a system including: (a) plural virtualization systems configured in a cluster; (b) storage accessible to each virtualization system of the cluster, wherein for each virtual machine operative in a virtualization system of the cluster, the storage maintains a representation of virtual machine state that includes at least a description of a hardware system virtualized and an image of virtualized memory state for the virtual machine; and (c) a failover system that, responsive to an interruption of, or on, a particular one of the virtualization systems, transitions at least one affected virtual machine to another virtualization system of the cluster and resumes computations of the transitioned virtual machine based on state encoded by a corresponding one of the virtual machine states represented in the storage.

Abstract: In one or more embodiments of the invention, communication among host agents providing high availability in a computer cluster is implemented by reading and writing to files on a shared data store. Each host agent holds a lock on a file on the shared data store corresponding to a liveness indicator for the host agent and a coordinator host agent periodically monitors the liveness indicators for host failures.

Abstract: A mobile station is configured to scan cells in a wireless network. The mobile station includes at least one antenna configured to transmit and receive wireless signals. The mobile station also includes a processor coupled to the at least one antenna, the processor configured to scan for one or more neighboring base station cells in a same frequency band as a serving base station cell using one or more receive beams. The one or more receive beams used for scanning are different than receive beams used for data communication with the serving base station cell.

Abstract: A method and apparatus report or identify channel quality information. The method for reporting includes selecting one or more beams for channel quality reporting. The method also includes mapping, by the UE, indices of the one or more selected beams to one or more channel quality values. Additionally, the method includes sending channel quality information for the one or more selected beams according to the mapping. The method for identifying includes receiving an indication of indices of one or more beams selected for reporting. The method also includes receiving channel quality information for the one or more selected beams. The method further includes identifying a mapping of the indices of the one or more selected beams to one or more channel quality values. Additionally, the method includes identifying a channel quality value for each of the one or more selected beams according to the mapping.

Abstract: Beam-steered millimeter wave signals transmitted in each of n sector slices include a sequence of primary synchronization (PSCH) symbols within predetermined symbol positions in at least one slot of a subframe. The symbols in consecutive symbol positions are each transmitted on a different one of the n slices, with the first symbol repeated on the same slice at the end. The sequence order rotates cyclically in each subframe so that two PSCH symbols are transmitted on one slice in a single subframe every nth subframe. Secondary synchronization (SSCH) and Broadcast Channel (BCH) symbols are transmitted in a predetermined pattern following the sequence of PSCH symbols. By transmitting consecutive PSCH symbols on different slices and repeating the first symbol, the mobile station can detect the best slice and beam by switching receive beams every subframe instead of every slot, relaxing time constraints on AGC adjustment while avoiding the start-at-the-edge problem.

Abstract: A device and method for device association, interference mitigation and channel selection for use in a visible light communication (VLC) network. The method includes transmitting on every one of a plurality of supported color channels of a first device to estimate an ambient interference on each supported color channel. The method also includes receiving a transmission on at least some of the supported color channels, where the number of receiving color channels is less than or equal to the number of supported color channels of the transmitter. The method further includes calculating a channel quality index for each of the receiving color channels. The method still further includes selecting at least one of the receiving color channels of the first device to be used as a communication channel. The method also includes reporting the at least one communication channel to a second device in the VLC network.

Abstract: A portable device capable of controlling a piconet selects a logical channel when forming the piconet. The device includes a controller configured to start a first piconet. The controller couples to at least one secondary device in the first piconet. The portable device also includes a transmitter configured to communicate with the at least one secondary device via a wireless communication channel. The controller is configured to select communication channel resources based at least in part on resources allocated to a second piconet in order to mitigate interference between the piconets. The controller is configured to form the first piconet to operate in either a non-interference mode when the controller is able to establish communications with a second controller in the second piconet or a coexistence interference mitigation mode when the controller is unable to establish communications with the second controller in the second piconet.

Abstract: A transmitter is capable of performing both Galois Field (GF) (16) and GF (256) encoding in a visual light communication system. The transmitter includes a GF (256) encoder. The transmitter also includes a first bit mapper configured to map a first number of bits to a second number of bits. The Galois Field (256) encoder is configured to receive and encode the second number of bits. The transmitter also includes a second bit mapper configured to map the second number of bits to the first number of bits. The transmitter also includes an interleaver unit that can pad bits based on a frame size and puncture the bits after interleaving and prior to transmission.

Abstract: A device is adapted for use in a body area network capable of low power communications wherein a number of piconets can operate within close proximity. The device is configured to couple to a plurality of secondary devices in a piconet. The device uses an interference mitigation technique to enable the devices in the piconet to use the same frequency and same time as a number of adjacent piconets located in close proximity to the piconet. The interference mitigation technique is at least one of a low duty cycling operation; and a preamble sequence designed to operate under interference.

Abstract: A transmitter or receiver may use beamforming methods for transmitting or receiving a signal in a communication system. The method for transmitting includes determining a first beamforming weight associated with a total number of antennas in an antenna array. The method also includes transmitting a first signal in a first beam having a first beam width using the total number of antennas by applying the first predetermined beamforming weight. The method further includes determining a second beamforming weight associated with a first sub-array of antennas in the antenna array and determining a third beamforming weight associated with a second sub-array of antennas in the antenna array. The method still further includes transmitting a second signal in a second beam having a second beam width using the first sub-array of antennas by applying the second beamforming weight and the second sub-array of antennas by applying the third beamforming weight.

Abstract: A method, apparatus, and system to transmit signals using multiple antennas with per-antenna power constraints. The method includes initializing a precoding algorithm to a complex matrix. The precoding algorithm is for precoding signals transmitted by a plurality of antennas. The method includes iteratively processing the precoding algorithm on a per-antenna basis by, at each iteration, sequentially updating a precoder for each of the plurality of antennas. The method includes, after each iteration, determining whether the precoding algorithm has converged based on a change in a rate of mutual information across iterations. Additionally, the method includes, in response to determining that the precoding algorithm has converged, transmitting the signals using the precoding algorithm.

Abstract: For use in visible light communication (VLC), methods for synchronization with multiple topology support and for transmitting an extended preamble. The method for synchronization includes transmitting a two-part preamble sequence. The preamble sequence includes one or more repetitions of a fast locking pattern (FLP) configured to be used for clock synchronization, and one or more repetitions of a topology dependent pattern (TDP) configured to be used to distinguish a plurality of VLC topologies. The method for transmitting an extended preamble includes generating an extended preamble and transmitting the extended preamble during a receive or idle mode for maintaining visibility support and for better synchronization performance.

Abstract: A method and apparatus for generating a bar code and for using a bar code to assist with positioning are provided. The method for generating a bar code to assist with positioning includes obtaining Global Positioning System (GPS) assistance data, generating a bar code with the GPS assistance data encoded therein, and displaying the bar code. The method for using a bar code to assist with positioning includes scanning a bar code, obtaining GPS assistance data from the scanned bar code, receiving and locking onto one or more GPS signals by using the GPS assistance data, and determining a position using the received one or more GPS signals.

Abstract: A method and apparatus enable combined baseband (BB) and radio frequency (RF) processing of signals. The method includes receiving, by a receiver, channel estimation information for a channel between a transmitter and the receiver. The method includes identifying a plurality of paths in the channel based on the channel estimation information. The method includes calculating an RF precoding matrix for precoding one or more signals to be transmitted on each of the identified paths. The RF precoding matrix includes a phase shift for each of the identified paths. Additionally, the method includes calculating a BB precoding matrix for precoding the one or more signals by a BB precoding unit associated with the transmitter.

Abstract: A method for restarting a virtual machine in a virtual computing system having a plurality of hosts and a resource scheduler for the plurality of hosts includes writing a placement request for the virtual machine to a shared channel that is accessible by the resource scheduler. The method further includes reading a placement result from the shared channel, wherein the placement result is generated by the resource scheduler responsive to the placement request; and restarting the virtual machine in accordance with the placement result.

Abstract: Embodiments maintain high availability of software application instances in a fault domain. Subordinate hosts are monitored by a master host. The subordinate hosts publish heartbeats via a network and datastores. Based at least in part on the published heartbeats, the master host determines the status of each subordinate host, distinguishing between subordinate hosts that are entirely inoperative and subordinate hosts that are operative but partitioned (e.g., unreachable via the network). The master host may restart software application instances, such as virtual machines, that are executed by inoperative subordinate hosts or that cease executing on partitioned subordinate hosts.

Abstract: The present invention provides a method for enabling side channel communication between wireless devices. In one embodiment of the invention the guard tones in wireless OFDM signals are used for side channel communication. In another embodiment of the invention, unused bits in OFDM symbols are used as side channels instead of being padded with zeros or random bits.

Abstract: A method for precise transmit power adjustment in a wide personal area network (WPAN) is provided that includes coarse adjusting a power level of the radio signal by adjusting a gain setting of an amplifier that is used to power the radio signal, and fine adjusting the power level of the radio signal by adjusting a voltage level of an information signal that is provided to the amplifier so that the power level of the radio signal approaches a maximum allowable power level.