Showing papers on "Signal published in 2013"

Full duplex radios

Abstract: This paper presents the design and implementation of the first in-band full duplex WiFi radios that can simultaneously transmit and receive on the same channel using standard WiFi 802.11ac PHYs and achieves close to the theoretical doubling of throughput in all practical deployment scenarios. Our design uses a single antenna for simultaneous TX/RX (i.e., the same resources as a standard half duplex system). We also propose novel analog and digital cancellation techniques that cancel the self interference to the receiver noise floor, and therefore ensure that there is no degradation to the received signal. We prototype our design by building our own analog circuit boards and integrating them with a fully WiFi-PHY compatible software radio implementation. We show experimentally that our design works robustly in noisy indoor environments, and provides close to the expected theoretical doubling of throughput in practice.

Powered surgical instrument having a transmission system

Abstract: A powered surgical apparatus for engaging tissue includes a housing assembly and a movable portion operatively connected to the housing assembly. The movable portion is movable with respect to the housing assembly. In addition, the surgical apparatus includes a power source configured to supply electrical power, and a transmission system configured to transfer at least one of a signal and electrical power between the handle assembly and the movable portion, the transmission system including a first electronic board disposed in the handle assembly and a second electronic board positioned in the movable portion, the second electronic board including a primary control circuit and a secondary control circuit wherein the movable portion is configured and adapted to rotate about a longitudinal axis defined by the powered surgical apparatus.

Ghost Talk: Mitigating EMI Signal Injection Attacks against Analog Sensors

Abstract: Electromagnetic interference (EMI) affects circuits by inducing voltages on conductors. Analog sensing of signals on the order of a few millivolts is particularly sensitive to interference. This work (1) measures the susceptibility of analog sensor systems to signal injection attacks by intentional, low-power emission of chosen electromagnetic waveforms, and (2) proposes defense mechanisms to reduce the risks. Our experiments use specially crafted EMI at varying power and distance to measure susceptibility of sensors in implantable medical devices and consumer electronics. Results show that at distances of 1-2m, consumer electronic devices containing microphones are vulnerable to the injection of bogus audio signals. Our measurements show that in free air, intentional EMI under 10 W can inhibit pacing and induce defibrillation shocks at distances up to 1-2m on implantable cardiac electronic devices. However, with the sensing leads and medical devices immersed in a saline bath to better approximate the human body, the same experiment decreases to about 5 cm. Our defenses range from prevention with simple analog shielding to detection with a signal contamination metric based on the root mean square of waveform amplitudes. Our contribution to securing cardiac devices includes a novel defense mechanism that probes for forged pacing pulses inconsistent with the refractory period of cardiac tissue.

Techniques for cutting and coagulating tissue for ultrasonic surgical instruments

Abstract: Various forms are directed to a method for operating an ultrasonic surgical instrument. The ultrasonic surgical instrument may be activated by generating a drive signal provided to the ultrasonic drive system to drive the end effector. A plurality of input variables may be applied to a multi-variable model to generate a multi-variable model output, where the multi-variable model output corresponds to an effect of the ultrasonic instrument on tissue. The plurality of input variables may comprise at least one variable describing the drive signal and at least one variable describing a property of the ultrasonic surgical instrument. When the multi-variable model output reaches a threshold value, feedback may be generated indicating a corresponding state of at least one of the ultrasonic surgical instrument and tissue acted upon by the ultrasonic surgical instrument.

High dynamic-range indicia reading system

Abstract: An indicia-reading system is provided that adjusts the intensity of an indicia signal to an optimal level in an efficient and timely manner The indicia-reading system incorporates an indicia-capturing subsystem for acquiring an indicia signal, a gain adjustment subsystem, and an indicia decoding subsystem The gain adjustment subsystem derives a plurality of derivative signals from the indicia signal At least two of the derivative signals have different gain adjustments from one another The indicia-decoding subsystem is configured to decode at least one of the derivative signals

Optical indicia reading apparatus with multiple image sensors

Abstract: Optical indicia reading apparatus can comprise a microprocessor, a memory, and a plurality of wafer level camera (WLC) modules. Each WLC module can comprise an image sensor and a focusing lens, and optionally, an optical band-pass filter (BPF) configured to pass light waves within a pre-defined wavelength range. Each WLC module can be configured to output a signal representative of the light incident on the image sensor. The optical axis of a first WLC module can be spatially disposed relatively to an optical axis of a second WLC module so that the fields of view (FOVs) of the WLC modules at least partially overlap. The depth of field (DOF) of a first WLC module can at least partially overlap with the DOF of a second WLC module. The optical indicia reading apparatus can be configured to generate an image frame by processing two or more signals of the plurality of signals outputted by the WLC modules. The optical indicia reading apparatus can be further configured to output an image frame comprising an image of decodable indicia and/or decoded message corresponding to the decodable indicia.

Method and system for power delivery to a headset

Abstract: A power delivery method and system for powering a headset. A power signal is combined with an audio signal to form a composite signal that is communicated over a shared channel to the headset. The power signal is generated by modulating a carrier signal with a modulation signal. The modulation signal is derived from the amplitude of the audio signal so that the peak levels of the composite signal do not exceed the maximum allowable output of an audio I/O circuit driving the headset.

Graphene mechanical oscillators with tunable frequency

Abstract: Oscillators, which produce continuous periodic signals from direct current power, are central to modern communications systems, with versatile applications including timing references and frequency modulators. However, conventional oscillators typically consist of macroscopic mechanical resonators such as quartz crystals, which require excessive off-chip space. Here, we report oscillators built on micrometre-size, atomically thin graphene nanomechanical resonators, whose frequencies can be electrostatically tuned by as much as 14%. Self-sustaining mechanical motion is generated and transduced at room temperature in these oscillators using simple electrical circuitry. The prototype graphene voltage-controlled oscillators exhibit frequency stability and a modulation bandwidth sufficient for the modulation of radiofrequency carrier signals. As a demonstration, we use a graphene oscillator as the active element for frequency-modulated signal generation and achieve efficient audio signal transmission.

Systems and/or methods for providing epdcch in a multiple carrier based and/or quasi-collated network

Abstract: ePDCCH may be provided. For example, a WTRU may receive a configuration for monitoring an ePDCCH resource. Based on the configuration, the WTRU may be configured to monitor and may monitor the ePDCCH resource on a particular subframe. Additionally, a WTRU may derive an aggregation level for a subframe associated with an aggregation level number NAL. The WTRU may transmit or monitor an ePDCCH using the aggregation level associated with the NAL for the subframe. A WTRU may also receive a reference signal. The WTRU may then determine the type of reference signal received. The WTRU may perform a demodulation of the PDSCH or ePDCCH using a demodulation timing based on the determined type. The ePDCCH or PDSCH may also be monitored or received by identifying a demodulation reference timing implicitly based on a location of one or more ePDCCH resources where the WTRU may receive DCI.

Towards a realistic transport modeling in a superconducting nanowire with Majorana fermions

Abstract: Motivated by recent experiments searching for Majorana fermions (MFs) in hybrid semiconducting-superconducting nanostructures, we consider a realistic tight-binding model and analyze its transport behavior numerically. In particular, we take into account the presence of a superconducting contact, used in real experiments to extract the current, which is usually not included in theoretical calculations. We show that important features emerge that are absent in simpler models, such as the shift in energy of the proximity gap signal, and the enhanced visibility of the topological gap for increased spin-orbit interaction. We find oscillations of the zero bias peak as a function of the magnetic field and study them analytically. We argue that many of the experimentally observed features hint at an actual spin-orbit interaction larger than the one typically assumed. However, even taking into account all the known ingredients of the experiments and exploring many parameter regimes for MFs, we are not able to reach full agreement with the reported data. Thus, a different physical origin for the observed zero-bias peak cannot be excluded.

The Use of Ensemble Empirical Mode Decomposition With Canonical Correlation Analysis as a Novel Artifact Removal Technique

Abstract: Biosignal measurement and processing is increasingly being deployed in ambulatory situations particularly in connected health applications. Such an environment dramatically increases the likelihood of artifacts which can occlude features of interest and reduce the quality of information available in the signal. If multichannel recordings are available for a given signal source, then there are currently a considerable range of methods which can suppress or in some cases remove the distorting effect of such artifacts. There are, however, considerably fewer techniques available if only a single-channel measurement is available and yet single-channel measurements are important where minimal instrumentation complexity is required. This paper describes a novel artifact removal technique for use in such a context. The technique known as ensemble empirical mode decomposition with canonical correlation analysis (EEMD-CCA) is capable of operating on single-channel measurements. The EEMD technique is first used to decompose the single-channel signal into a multidimensional signal. The CCA technique is then employed to isolate the artifact components from the underlying signal using second-order statistics. The new technique is tested against the currently available wavelet denoising and EEMD-ICA techniques using both electroencephalography and functional near-infrared spectroscopy data and is shown to produce significantly improved results.

Detection and Diagnosis of Faults in Induction Motor Using an Improved Artificial Ant Clustering Technique

Abstract: The presence of electrical and mechanical faults in the induction motors (IMs) can be detected by analysis of the stator current spectrum. However, when an IM is fed by a frequency converter, the spectral analysis of stator current signal becomes difficult. For this reason, the monitoring must depend on multiple signatures in order to reduce the effect of harmonic disturbance on the motor-phase current. The aim of this paper is the description of a new approach for fault detection and diagnosis of IMs using signal-based method. It is based on signal processing and an unsupervised classification technique called the artificial ant clustering. The proposed approach is tested on a squirrel-cage IM of 5.5 kW in order to detect broken rotor bars and bearing failure at different load levels. The experimental results prove the efficiency of our approach compared with supervised classification methods in condition monitoring of electrical machines.

Enhanced rate physical layer for Bluetooth™ low energy

Abstract: A method of communicating data in a Bluetooth™ low energy (BLE) module is provided. The method includes modulating an outbound communication signal into a modulated signal with a particular modulation scheme based on a modulation type, and transmitting the modulated signal to a remote device via a wireless communication connection associated with the modulation type. The method also includes receiving an inbound radio frequency (RF) signal, determining if the inbound RF signal is associated with a modulation type, and demodulating the inbound RF signal with a particular modulation scheme based on the modulation type if the inbound RF signal is determined to be associated with a modulation type. In some aspects, the inbound RF signal and outbound modulated signal have symbol rates of 2 Megasymbols per second. In some implementations, the method includes switching between a legacy BLE system and an enhanced rate BLE system.

Method and an apparatus for processing a video signal

Abstract: An apparatus for processing a video signal and method thereof are disclosed. The present invention includes receiving prediction mode information, interpolating information and a residual of a current block, reconstructing an interpolating pixel using the interpolating information and a neighbor block, and reconstructing the current block using the interpolating pixel, the prediction mode information and the residual, wherein the interpolating information is generated based on a location of the current block. According to an apparatus and method for processing a video signal, high reconstruction rate can be obtained by improving the related art method having limited intra prediction modes available for a current block located on a boundary area of a picture in encoding in a manner of reconstructing and using an interpolating pixel based on interpolating information.

Method and apparatus for executing voice command in electronic device

Abstract: An apparatus and method for executing a voice command in an electronic device. In an exemplary embodiment, a voice signal is detected and speech thereof is recognized. When the recognized speech contains a wakeup command, a voice command mode is activated, and a signal containing at least a portion of the detected voice signal is transmitted to a server. The server generates a control signal or a result signal corresponding to the voice command, and transmits the same to the electronic device. The device receives and processes the control or result signal, and awakens. Thereby, voice commands are executed without the need for the user to physically touch the electronic device.

Physiological trend monitor

Abstract: A physiological trend monitor has a sensor signal responsive to multiple wavelengths of light transmitted into a tissue site. The transmitted light is detected after attenuation by pulsatile blood flow within the tissue site. A processor has an input responsive to the sensor signal and a physiological parameter output. Features are extracted from the physiological parameter output. Criteria are applied to the features. An alarm output is generated when the criteria are satisfied.

Methods and systems for determining the location of an electronic device using multi-tone frequency signals

Abstract: Embodiments of the present invention include a method of determining a location of a mobile device. The method comprises transmitting a signal between a plurality of known locations and receiving signal at device of unknown location such as a mobile device. The signal may include multiple tones having different frequencies and resulting in sets of residual phase differences. The location of the mobile device may be determined using the known locations and the frequency and phase differences between the transmitted tones. In one embodiment, OFDM signals may be used between an access point and mobile device, for example, to determine the location of the mobile device.

PSII Fluorescence Techniques for Measurement of Drought and High Temperature Stress Signal in Crop Plants: Protocols and Applications

Abstract: Field crops are frequently exposed to drought and high temperature in the field. As the stress tolerance is the major target of many research and breeding programmes, the efficient and reliable tools and methods useful in screening of the heat and drought stress effects are required. The techniques based on measurement of chlorophyll fluorescence induction belong recently to fundamentals of plant stress research; however, in most cases the very basic tools are used and its potential is not utilised sufficiently. This proposed chapter tries to summarise the knowledge, starting from basic theory through parameters and useful experimental protocols and results up to special kinds of application of chlorophyll fluorescence techniques. In addition to generally used pulse-amplitude-modulated (PAM) method with saturation pulse analysis, the fast fluorescence kinetics, the fluorescence imaging, as well as simultaneous measurements of chlorophyll fluorescence with other parameters and their potential application in drought and heat-stress research are discussed.

QuShape: rapid, accurate, and best-practices quantification of nucleic acid probing information, resolved by capillary electrophoresis.

Abstract: Chemical probing of RNA and DNA structure is a widely used and highly informative approach for examining nucleic acid structure and for evaluating interactions with protein and small-molecule ligands. Use of capillary electrophoresis to analyze chemical probing experiments yields hundreds of nucleotides of information per experiment and can be performed on automated instruments. Extraction of the information from capillary electrophoresis electropherograms is a computationally intensive multistep analytical process, and no current software provides rapid, automated, and accurate data analysis. To overcome this bottleneck, we developed a platform-independent, user-friendly software package, QuShape, that yields quantitatively accurate nucleotide reactivity information with minimal user supervision. QuShape incorporates newly developed algorithms for signal decay correction, alignment of time-varying signals within and across capillaries and relative to the RNA nucleotide sequence, and signal scaling across channels or experiments. An analysis-by-reference option enables multiple, related experiments to be fully analyzed in minutes. We illustrate the usefulness and robustness of QuShape by analysis of RNA SHAPE (selective 29-hydroxyl acylation analyzed by primer extension) experiments.

Resolving communications in a wireless power system with co-located transmitters

Abstract: In one aspect, a wireless charger may include a wireless power antenna, a wireless power transmitter coupled to the wireless power antenna and configured to generate a wireless charging field in a charging region, a first communication antenna, a first transceiver coupled to the communication antenna and configured to communicate with the chargeable device via the communication antenna, a first signal strength detector configured to determine a signal strength of a first signal received by the transceiver, and a controller configured to determine whether the chargeable device is within the charging region based at least in part on the signal strength of the first signal.

Effects of image reconstruction on fiber orientation mapping from multichannel diffusion MRI: reducing the noise floor using SENSE.

Abstract: Purpose: To examine the effects of the reconstruction algorithm of magnitude images from multi-channel diffusion MRI on fibre orientation estimation. Theory and Methods: It is well established that the method used to combine signals from different coil elements in multi-channel MRI can have an impact on the properties of the reconstructed magnitude image. Utilising a root-sum-of-squares (RSoS) approach results in a magnitude signal that follows an effective non-central-distribution. As a result, the noise floor, the minimum measurable in the absence of any true signal, is elevated. This is particularly relevant for diffusion-weighted MRI, where the signal attenuation is of interest. Results: In this study, we illustrate problems that such image reconstruction characteristics may cause in the estimation of fibre orientations, both for model-based and model-free approaches, when modern 32-channel coils are employed. We further propose an alternative image reconstruction method that is based on sensitivity encoding (SENSE) and preserves the Rician nature of the single-channel, magnitude MR signal. We show that for the same k-space data, RSoS can cause excessive overfitting and reduced precision in orientation estimation compared to the SENSE-based approach. Conclusion: These results highlight the importance of choosing the appropriate image reconstruction method for tractography studies that use multi-channel receiver coils for diffusion MRI acquisition.

Distributed antenna system for MIMO signals

Abstract: A distributed antenna system includes a multiple-input and multiple-output (MIMO) base station configured to output at least a first signal and a second signal. At least one master unit communicates with the MIMO base station. At least one remote unit communicates with the master unit. At least one antenna is coupled with the remote unit for receiving signals from the remote unit. A hybrid coupler is coupled between the remote unit and antenna and is configured to receive the first signal Ch1 and the second signal Ch2 from the remote unit on respective first and second ports and to provide an output signal on at least one output port. The output signal includes at least a portion of the first signal and at least a portion of the second signal. The antenna is coupled with the output port.

Waveform Calibration Using Built In Self Test Mechanism

Abstract: A system on a chip (SoC) includes a transceiver comprising a transmitter having a power amplifier and a receiver having a signal buffer. At least one of the transmitter and receiver has a configurable portion that can be configured to produce a range of waveforms (both in waveshape as well as duty cycle). A low cost built in self test (BIST) logic is coupled to the transceiver. The BIST logic is operable to calibrate the configurable portion of the transceiver to produce a waveform that has a selected harmonic component that has an amplitude that is less than a threshold value. Current consumed by the transceiver may be dynamically reduced by selecting an optimized waveform that has low harmonic components.

Brain-computer interface technologies: from signal to action.

Abstract: Here, we present a state-of-the-art review of the research performed on the brain-computer interface (BCI) technologies with a focus on signal processing approaches. BCI can be divided into three main components: signal acquisition, signal processing, and effector device. The signal acquisition component is generally divided into two categories: noninvasive and invasive. For noninvasive, this review focuses on electroencephalogram. For the invasive, the review includes electrocorticography, local field potentials, multiple-unit activity, and single-unit action potentials. Signal processing techniques reviewed are divided into time-frequency methods such as Fourier transform, autoregressive models, wavelets, and Kalman filter and spatiotemporal techniques such as Laplacian filter and common spatial patterns. Additionally, various signal feature classification algorithms are discussed such as linear discriminant analysis, support vector machines, artificial neural networks, and Bayesian classifiers. The article ends with a discussion of challenges facing BCI and concluding remarks on the future of the technology.

Real-time wireless power transfer control for passive backscattering devices

Abstract: A method and apparatus is disclosed herein for real-time wireless power transfer control. In one embodiment, a system comprises: an RF-energy harvesting sensor tag operable to generate a first backscatter signal and at least one base station operable to deliver RF power to the sensor tag by emitting a first waveform comprising a plurality of subcarriers, wherein the first backscatter signal is generated by the sensor tag by modulated scattering of the first waveform as incident upon the sensor tag, and further wherein the at least one base station subsequently emits a second waveform determined at least in part by a closed-loop feedback control algorithm responsive to measurements of the first backscatter signal.

Hybrid wi-fi and power router transmitter

Abstract: The present disclosure may provide an hybrid transmitter which may be used to provide wireless power transmission (WPT). In some embodiments, hybrid transmitters may include antenna elements designed to transmit WI-Fi signal or to function as power router which may function simultaneously. In other embodiments, hybrid transmitters may only transmit a single signal and a switch may change the operation mode. In addition, transmitters may include communications components which may allow for communication to various electronic equipment including phones, computers and others.

Method and device for reporting channel state information in wireless communication system

Abstract: A method of reporting channel state information (CSI) on a terminal in which a plurality of CSI processes are configured in a wireless communication system according to an embodiment of the present invention includes: measuring a channel based on a CSI reference signal (RS) resource related to one of the CSI processes; measuring interference based on a CSI-interference measurement (IM) resource related to the CSI process; determining CSI based on the measured channel and the measured interference; and reporting the CSI through an uplink channel, wherein a codebook for reporting the CSI, which is used for determining the CSI, is one of two or more codebooks that correspond independently to each of the CSI processes.