Abstract: Methods and apparatus for interleaving priorities of a plurality of virtual processors are disclosed. A hypervisor assigns a base priority to each virtual processor and schedules one or more virtual processors to execute on one or more physical processors based on the current priority associated with each virtual processor. When the hypervisor receives an indication from one of the virtual processors that its current priority may be temporarily reduced, the hypervisor lowers the current priority of that virtual processor. The hypervisor then schedules another virtual processor to execute on a physical processor instead of the virtual processor with the temporarily reduced priority. When the hypervisor receives an interrupt for the virtual processor with the lowered priority, the hypervisor raises the priority of that virtual processor and schedules the virtual processor with the restored priority to execute on a physical processor so that processor can handle the interrupt.

Abstract: The present disclosure provides methods and apparatus for constructing a secure and flexible operating system. The presently disclosed system executes different user applications in different operating systems on different virtual machines. Each user application communicates with other processes via the hypertext transfer protocol (HTTP). In particular, each user application's user interface is implemented in a web browser that is running in its own operating system on its own virtual machine, and each user application interacts with the user interface by exchanging HTTP messages between the virtual machines.

Abstract: A relay device for supporting communications between a terminal device and a base station in a wireless communications system is described. The relay device comprises a transceiver arranged to at least receive an access request message from the terminal device; and a control processor operably coupled to the transceiver and arranged to process the access request message, extract information and determine therefrom a power delta value that is not based on a determination of pathloss between the relay device and the terminal device, generate a control element comprising the power delta value; and for relaying at least the control element to the base station. The control processor is further arranged to receive subsequently at least one physical uplink channel message from the terminal device wherein a transmit power level of the at least one physical uplink channel message is based at least on the power delta value.

Abstract: A terminal device is arranged to communicate with a base station via a relay device in a wireless communications system. The terminal device comprises: a transmitter arranged to transmit a first access request message to the base station wherein the access request message comprises one from a set of access preambles that indicate relay device uplink assistance is required; a receiver arranged to receive an access request grant response from the base station; and a control processor operably coupled to the transmitter and receiver and arranged to: process the access request grant response; extract transmit power control information therefrom for transmissions to the relay device; map a first power level indicated in the transmit power control information to a second power level associated with a transmission via the relay device; and generate and transmit a transmission to the relay device at the mapped transmit second power level.

Abstract: A terminal device is arranged to communicate with a base station via a relay device in a wireless communications system. The terminal device comprises: a transmitter arranged to transmit an access request message to the base station, wherein the access request message comprises one from a set of access preambles that indicate relay device uplink assistance is required; a receiver arranged to receive an access request grant response from the base station; and a control processor operably coupled to the transmitter and receiver and arranged to: process the access request grant response and determine from a timing advance part thereof transmit power control (TPC) information for transmitting to the base station via the relay device.

Abstract: A relay device is described for supporting communications between a terminal device and a base station, the relay device comprises: at least one receiver; and a control processor, operably coupled to the at least one receiver and arranged to: monitor a downlink communication from the base station to the terminal device; determine therefrom at least one uplink resource to be used by the terminal device; configure the at least one receiver to receive the at least one uplink resource; receive an uplink message on the at least one uplink resource; determine therefrom uplink control information used by the terminal device; modify the uplink message on the at least one uplink resource; and relay the uplink message to the base station.

Abstract: A relay device for supporting uplink communication between a terminal device and a base station is described. The relay device comprises at least one receiver arranged to receive a downlink message from the base station; a control processor, operably coupled to the at least one receiver and arranged to determine from the downlink message information identifying an uplink control resource to be used by the terminal device; and a transmitter, operably coupled to the control processor and arranged to relay received periodic uplink control channel messages on the identified uplink control resource from the terminal device to the base station.

Abstract: Cutting apparatus includes a pilot arrangement which has a tip. The tip engages a workpiece to form a pilot recess to engage the workpiece and prevent the apparatus skidding across the surface of the workpiece. The tip can retract against the action of a spring. Accordingly, the apparatus is prevented from skidding across the workpiece, but wear on the tip is minimized.

Abstract: Methods and apparatus for synchronizing multiple virtual processors of a virtual machine are disclosed. A hypervisor schedules a first virtual processor in a virtual machine to execute using a first physical processor. Subsequently, the hypervisor receives an indication from the first virtual processor that it is waiting on a second different virtual processor. If the second virtual processor is not already running on another physical processor, the hypervisor saves the priority associated with the first virtual processor, lowers the priority associated with the first virtual processor, and schedules the second virtual processor to execute using the first physical processor or another physical processor.

Abstract: A communication system is provided that includes a transmitter device and a receiver device. The transmitter device transmits input data as a transmitted signal having the known non-linear distortion (NLD) characteristic. The receiver receives a received signal that represents a channel affected version of the transmitted signal and that has the known NLD characteristic. The received signal includes power amplifier distortion (PAD) induced by the transmitter device's power amplifier. The receiver is designed to iteratively estimate, based on the known NLD characteristic, remaining PAD caused by the power amplifier, and to iteratively cancel estimated PAD to reduce PAD in the received signal.

Abstract: Embodiments include methods and apparatus for performing symbol timing synchronization for a symbol-bearing signal. The symbol-bearing signal is sampled to produce a plurality of symbol samples. First-direction interpolation processes are performed on the plurality of symbol samples in a first temporal direction, where the first temporal direction is a direction from a first sampling time towards a second sampling time. In addition, second-direction interpolation processes are performed on the symbol samples in a second temporal direction, where the second temporal direction is a direction from the second sampling time towards the first sampling time, resulting in a set of interpolated symbol samples.

Abstract: Systems and methods are described for processing a digital signal. In one embodiment, the method comprises receiving time-aligned input samples of an input signal; computing at least one moment using the time-aligned input samples; determining at least one of signal energy per symbol and noise power spectral density based on the at least one moment; and adjusting an input signal level based on the at least one of the signal energy per symbol and the noise power spectral density.

Abstract: A blade comprises a strip having a main body portion and an edge portion. Cutting medium in the form of a diamond grit is secured to the strip by braze material. The edge portion is thinner than the main body portion.

Abstract: A phase shift device includes an input quadrature junction for receiving an input EM signal and extracting a first electromagnetic (EM) signal, a second EM signal, a third EM signal, and a fourth EM signal from the input EM signal. Four waveguide arms are operatively connected to the input quadrature junction for respectively conveying the first, second, third, and fourth EM signals therethrough. At least two of the waveguide arms shift the phase of EM signal conveyed therethrough such that two of the first, second, third, and fourth EM signals are phase shifted with respect to the other two of the first, second, third, and fourth EM signals. An output quadrature junction is operatively connected to the waveguide arms for combining the first, second, third, and fourth EM signals. Thus, polarization adjustment may be achieved through rotation of the phase shift device.

Abstract: In a wireless ad hoc network (20) of nodes (22), a method (64) of power management entails monitoring (82) a current traffic load of the network (20), and in response to the current traffic load, selecting (106, 132) a subset (102) of epochs (80) within cyclically repeating time windows (78) for network communication. A message (122) is communicated (120) between the nodes (22) in the network (20). The message (122) identifies the subset (102) of epochs (80) for using in communicating network traffic (32). Following receipt of the message, each of the nodes (22) modifies (124) a transmit capability mode by entering a run state (40) during the epochs (80) within the subset (102) to enable communication of network traffic (32) and by entering a low power consumption idle state (42) during the remaining epochs (80) within the time window (78).

Abstract: Systems and methods are described for efficiently transmitting packetized data from a sender to a receiver over a communications link. A compression context is established between the sender and the receiver based upon commonalities in each of the data packets prior to transmitting the data over the communications link. The data is compressed according to the compression context to thereby create compressed data packets, and the compressed data packets are transmitted to the receiver across the communications link. By establishing compression contexts prior to transmission, the need for in-band signaling is reduced or eliminated.

Abstract: A processing system (60) includes an input interface (62), a first processor (64), a second processor (66), and an output interface (68) arranged in a serial configuration. Each of the input interface (62), first processor (64), second processor (66), and output interface (68) computes a digest (92, 100, 110, and 114) using information, e.g., a unique parameter (94, 102, 112, 118), known only by that element (62, 64, 66, 68) and using information generated by that element (62, 64, 66, 68). The digests (92, 100, 110, and 114) are used to validate the integrity of payload data (86) processed by the system (60) to form processed data (104) and the system (60) only outputs the processed data (104) upon validation of data integrity. The serial configuration of system (60) may be implemented to provide high bit rate, redundant cryptographic services.

Abstract: Embodiments include methods for determining synchronization/pilot sequences (SPS) to be utilized in conjunction with transmissions by antennas of a multiple-antenna transmitter. The SPS include pilot signals that are positioned at subcarriers that are orthogonal in frequency with subcarriers at which pilot signals of other antennas are positioned. The pilot signals may be unevenly spaced across the in-band subcarriers. The multiple-antenna transmit system generates a plurality of wireless signals, each of which may include an SPS having synchronization information in a first plurality of in-band subcarriers and the pilot signals in a second plurality of in-band subcarriers. The wireless signals are simultaneously radiated over a wireless communication channel using a different antenna. A receiver receives channel-affected versions of the wireless signals, and produces a corrected signal by applying corrections to the received signal based on estimated channel perturbations within the received signal.

Abstract: An embodiment includes a method for generating a set of synchronization/pilot sequences (SPS) by generating a plurality of candidate SPS using different initial conditions. Correlations are performed among the candidate SPS to generate a plurality of correlation values, and a plurality of permutations of the candidate SPS are determined, where each permutation includes a different set of candidate SPS, and wherein each permutation includes a number, D, of candidate SPS. In addition a selected permutation is identified from the plurality of permutations, where the selected permutation corresponds to the set of SPS being generated. A system includes a transmitter adapted to generate a wireless signal in which an SPS is embedded by combining each SPS of the set with phase shifted input data, determining peak-to-average power ratios (PARs) for at least some of the combined signals, and identifying a selected combined signal based on the PARs.

Abstract: A method and system are provided for reducing power amplifier induced distortion. Power amplifier induced distortion is iteratively estimated and cancelled. When the difference between the current estimated power amplifier distortion and the previous estimated power amplifier distortion is less than a convergence threshold, particular M-QAM constellation points that are still in error are determined A M-QAM constellation point correction routine is provided that can move the incorrectly estimated M-QAM constellation points that are in error towards their expected quadrants by generating updated M-QAM constellation points. The remaining estimated non-linear power amplifier induced distortion in the received signal can then be estimated and canceled.