Abstract: A system for recovering a signal of interest from a complex signal is provided. The system includes a plurality of different oscillators. Each of the plurality of oscillators is configured to facilitate improving a signal-to-noise ratio of an input complex signal by adjusting an oscillation frequency of each of the plurality of oscillators based on an input frequency of interest of the input complex signal.

Abstract: A method of processing data acquired by under-sampling a chirped, sinusoidal waveform comprises complex-heterodyning the under-sampled data with a chirped signal having characteristics similar to the sinusoidal waveform to generate a demodulated signal and analyzing the demodulated signal to determine characteristics of the sinusoidal waveform.

Abstract: A frequency error estimation algorithm is presented for use in radio receivers, for example. The present algorithm utilizes irregular time intervals between pilot symbols to improve the frequency range of the estimate. First, a first phase rotation indicator comprising information on phase rotation of a received signal within a first time interval is estimated. Then, a second phase rotation indicator comprising information on phase rotation of the received signal within a second time interval of a different length than the first time interval is estimated. A frequency error estimate is calculated from the phase difference between the first phase rotation indicator and the second phase rotation indicator, for example by dividing the phase difference by the difference in the lengths of the first and the second time interval.

Abstract: A signal processing circuit and a method for processing an HF input signal are described, having an HF receiver for generating an IF signal on an intermediate frequency from an HF input signal, a frequency divider for generating a signal from the IF signal or a signal derived from the IF signal, with a frequency reduced compared with the intermediate frequency, and a sampling unit for sampling the signal with the reduced frequency by using a sampling frequency, wherein the sampling frequency is smaller than the double intermediate frequency, and wherein the frequency divider divides the intermediate frequency such that the reduced frequency and the sampling frequency are spaced such that the sampling theorem is fulfilled at least for the first odd-numbered harmonic of the signal with the reduced frequency.

Abstract: A point of sale terminal includes a microcontroller integrated circuit. In one aspect, a regulator within the IC receives power from a supply voltage terminal and/or a battery terminal. If the regulator does not receive adequate power from either terminal, then energy stored on-chip in a capacitor is used to erase secure memory. In another aspect, pulses of current are made to pulse through conductors of a conductive mesh. A tamper condition is detected if an improper voltage is detected on the IC terminal through which the pulse is conducted. In another aspect, each vendor signs his/her firmware with his own vendor ID. A bootloader uses the vendor ID to lookup a public key that is then used to verify a private key supplied by the firmware to be executed. In another aspect, a magnetic card reader includes a digital peak detector circuit involving programmable positive and negative thresholds.

Abstract: Methods of rapidly measuring the impedance spectrum of an energy storage device in-situ over a limited number of logarithmically distributed frequencies are described. An energy storage device is excited with a known input signal, and the response is measured to ascertain the impedance spectrum. The excitation signal is a limited time duration sum-of-sines consisting of a select number of frequencies. In one embodiment, magnitude and phase of each of frequency of interest within the sum-of-sines is identified when the selected frequencies and sample rate are logarithmic integer steps greater than two. This technique requires a measurement with a duration of one period of the lowest frequency. In another embodiment, where the selected frequencies are distributed in octave steps, the impedance spectrum can be determined using a captured time record that is reduced to a half-period of the lowest frequency.

Abstract: A system and method for monitoring RF power is described. In one embodiment the system samples RF power that is generated by an RF generator to obtain RF signals that include information indicative of electrical characteristics at a plurality of particular frequencies that fall within a frequency range. The RF signals are digitized to obtain a stream of digital RF signals that include information indicative of electrical characteristics at the plurality of particular frequencies, and the information indicative of electrical characteristics is successively transformed, for each of the plurality of particular frequencies, from a time domain into a frequency domain.

Abstract: This disclosure relates to channel assessment and selection for wireless communication between two or more medical devices, such as between an implantable medical device (IMD) and a non-implanted medical device, between two IMDs, or between two non-implanted medical devices. A telemetry module of a medical device operating in accordance with the techniques of this disclosure obtains measured ambient power levels on a plurality of channels of a frequency band regulation, such as the ten channels of the MICS band regulation. The telemetry module computes channel assessment values for at least a portion of the plurality of channels based on the measured ambient power levels on at least one other channel of the plurality of channels and selects a channel to transmit on based on the channel assessment values.

Abstract: The present invention offers an object proximity detector and object position detector. The variation of frequency of an oscillator is used to detect the proximity of an object to a sensor plate. The dependence of the sensitivity of the detector on the area of the sensor plate is reduced by conducting the sensor plate to two capacitors in series. The conducting wire of the sensor plate can be flexible without causing error detection. In the sensor element of the sensor oscillator, a resistor is connected at one terminal of the sensor plate to form a high pass filter. A resistor and a capacitor are added to the sensor oscillator to form a low pass filter. The high pass filter is used to reduce the low frequency electromagnetic interference. The low pass filter is used to reduce the high frequency electromagnetic interference.

Abstract: A frequency selective surface (FSS) and associated methods for modeling, analyzing and designing the FSS are disclosed. The FSS includes a pattern of conductive material formed on a substrate to form an array of resonance elements. At least one aspect of the frequency selective surface is determined by defining a frequency range including multiple frequency values, determining a frequency dependent permittivity across the frequency range for the substrate, determining a frequency dependent conductivity across the frequency range for the conductive material, and analyzing the frequency selective surface using a method of moments analysis at each of the multiple frequency values for an incident electromagnetic energy impinging on the frequency selective surface. The frequency dependent permittivity and the frequency dependent conductivity are included in the method of moments analysis.

Abstract: An Edge-Aligned Ratio Counter (EARC) that includes at least one processor coupled to at least one counter circuit is provided for determining a ratio between two clock signals by receiving a first and a second value in response to a first clock signal and generating a control signal under control of the loaded value by counting the pulses of the first clock signal and a second clock signal and captures the count of each clock signal in response to the control signal and determining a ratio between a frequency of the first clock signal and a frequency of the second clock signal using the differences of the captured counts taken at two different occurrences of the control signal.

Abstract: A method for filling level measuring comprises generating an echo curve and analysing the echo curve by means of an analysis method. The analysis method is at least one analysis method selected from the group of analysis methods comprising analysing the echo curve by means of at least two parallel tasks, and analysing the echo curve by comparing the echo curve with a spurious-echo curve at the IF-level.

Abstract: There is provided a measuring apparatus for measuring a signal-to-noise ratio of a discrete waveform which is output from an AD converter in response to an input signal, where the signal-to-noise ratio indicates a ratio of a signal component of the input signal to noise generated by the AD converter. The measuring apparatus includes a spectrum compensating section that receives a spectrum of the discrete waveform output from the AD converter, and compensates the received spectrum in accordance with a non-symmetric sideband between an upper sideband and a lower sideband of the received spectrum, where the upper and lower sidebands are defined with respect to a fundamental frequency of the input signal, and a phase noise waveform calculating section that calculates a phase noise waveform of the discrete waveform based on the spectrum which has been compensated by the spectrum compensating section.

Abstract: Systems and methods are provided for acquiring seismic data using a wireless network and a number of individual data acquisition modules that are configured to collect seismic data and forward data to a central recording and control system. In one implementation, a number of remote modules (301) are arranged in lines. Base station modules (302) receive information from the lines and relay the information to a central control and recording system (303). Radio links operating on multiple frequencies (F1-F12) are used by the modules (301). For improved data transfer rate, radio links from a remote module (301) leap past the nearest remote module to the next module closer to the base station.

Abstract: Method for compensating for phase errors in electromagnetic data by exploiting the frequency scaling properties of electromagnetic fields. The data are obtained at various source-receiver offsets. Then, temporal frequency components of the data at each offset R are determined. Next, the phase spectrum (phase vs. offset) for each of the frequency components is determined. Then, the phase spectra for the different frequencies f are displayed vs. scaled offset R??, where ?=2?f . Finally, the phase spectra are then adjusted such that the differences in phases for the different frequencies are reduced. The adjustment process can be repeated until phase differences are reduced to an acceptable level.

Abstract: A method and apparatus for detecting arcs in a plasma processing system is disclosed. In one embodiment the apparatus comprises an input to receive a measured value of a parameter related to power transfer from the RF power generator to a plasma load; arc detection circuitry that computes a dynamic boundary about the value of the parameter; and controller logic responsive to the arc detection circuitry, wherein the controller logic indicates an occurrence of an arc within the plasma load if a subsequent value of the parameter exceeds the dynamic boundary.

Abstract: Time correlation of signal to distortion characteristics is achieved by acquiring time domain data for a frequency band representing a communication signal, the communication signal having multiple channels. The time domain data is simultaneously converted to frequency and demodulation domain data in sequential time blocks. The frequency and demodulation domain data are processed to obtain respectively frequency and demodulation domain measurements. The resulting measurements are displayed simultaneously as a function of time for all the time blocks and/or for a selected one of the time blocks. An ACLRogram display provides a display having a time axis and a frequency axis in the form of bars spanning the frequency band for each time block with each bar being divided into frequency sub-bands representing a main channel and adjacent side channels, the shading of each segment of the bar representing a measurement value for that segment.

Abstract: Independent frequency measurement and tracking of a signal using a measurement interval where the frequency of the signal is measured and a sampling rate is calculated, and a settling interval where the frequency of the signal is not measured. The sampling rate is calculated to correspond with the frequency of the signal and updated only after the calculation of the sampling rate in the measuring interval. The signal may be a signal of an electric power system such as a voltage waveform or a current waveform. The frequency calculation may include determination of a rate of rotation of a positive-sequence phasor of the signal.

Abstract: Systems and techniques are disclosed relating to communications. The systems and techniques include determining the temperature and process speed of chips used in communications devices. The systems and techniques include measuring the output of ring oscillators embedded in the chips, and calculating the temperature and process speed therefrom.

Abstract: A method of characterizing the overlap of two media segments is provided. In an instance where there is some amount of overlap of a file and a data sample, the file could be an excerpt of an original file and begin and end within the data sample. By matching identified features of the file with identified features of the data sample, a beginning and ending time of a portion of the file that is within the data sample can be determined. Using these times, a length of the file within the data sample can also be determined.

Abstract: An instantaneous frequency measurement (IFM) receiver includes a receiver module for determining a frequency fe of a received signal. Also included is a discrete Fourier transform (DFT) module configured to sum values of digital samples of data in a block of data, wherein the values of the digital samples of data are based on the frequency fe. A confirmation module confirms the frequency fe, if the sum has a value greater than a predetermined threshold. The DFT module is configured to obtain the sum of N-sample points of data which are disposed in the block of data by using a DFT kernel function.

Abstract: In a method for performing a frequency analysis of an AC voltage signal, in particular in a power mains, an upper limit of the period length of a fundamental oscillation in the AC voltage signal is determined. A sequence of sampling values of the AC voltage signal is obtained over a duration longer than the upper limit of the period length, thereby ensuring that more than a period of the fundamental oscillation is sampled. Selected from the sequence of sampling values is a subset of sampling values, with the subset sampling substantially one period of the fundamental oscillation. At least a portion of the sampling values not included in the subset is altered, and a frequency is calculated based on the obtained sequence of sampling values, the subset of sampling values and the altered portion of the sampling values.

Abstract: Methods and systems for improving frequency estimation without increasing digital counter resolution. An example system mixes and filters a known carrier signal with the signal containing the frequency of interest, in order to bring the frequency domain image closer to baseband, and then performs the frequency estimation. This allows much better resolution without the need to increase the counter frequency.

Abstract: A method of synthesizing nondestructive examination data of a component that combines data sets acquired at least two different frequencies. At least one of the data sets is interpolated or extrapolated to the equivalent of data acquired at one of the other frequencies employing a third, reference set of eddy current inspection data that is acquired at each of the inspection frequencies being combined.

Abstract: A signal processing system compensates for the relative phase difference between multiple frequency bands so that the combination of the bands is constructive throughout a substantial portion of the band overlap or crossover region. In one embodiment, a signal combining system may include a comparator for determining a relative phase difference between the two signals within a predefined crossover region, a phase adjusting element for adjusting a phase of one of the two signals; and a combiner for combining the phase-adjusted signal and the other of the two signals.

Abstract: One embodiment of the present invention provides a system that efficiently conducts vibrational characterizations for a computer system having variable component configurations. During operation, the system receives a given component configuration associated with the computer system. Next, the system looks up the given component configuration in a resonant spectra library, which contains structural resonant frequencies for a number of possible component configurations for the computer system. If the given component configuration is found in the resonant spectra library, the system retrieves a set of structural resonant frequencies associated with the given component configuration. The system subsequently controls one or more vibration sources within the computer system to avoid the set of structural resonant frequencies.

Abstract: A method for locally creating effectively homogeneous or “clean” magnetic field gradients (of high uniformity) for imaging (with NMR, MRI, or spectroscopic MRI) both in in-situ and ex-situ systems with high degrees of inhomogeneous field strength. The method of imaging comprises: a) providing a functional approximation of an inhomogeneous static magnetic field strength B0 (r) at a spatial position r; b) providing a temporal functional approximation of Gshim(t) with i basis functions and j variables for each basis function, resulting in vij variables; c) providing a measured value ?, which is an temporally accumulated dephasing due to the inhomogeneities of B0 (r); and d) minimizing a difference in the local dephasing angle (I) by varying the vij variables to form a set of minimized vij variables. The method requires calibration of the static fields prior to minimization, but may thereafter he implemented without such calibration, may he used in open or closed systems, and potentially portable systems.

Abstract: The present invention provides a system and method for representing quasi-periodic (“qp”) waveforms comprising, representing a plurality of limited decompositions of the qp waveform, wherein each decomposition includes a first and second amplitude value and at least one time value. In some embodiments, each of the decompositions is phase adjusted such that the arithmetic sum of the plurality of limited decompositions reconstructs the qp waveform. These decompositions are stored into a data structure having a plurality of attributes. Optionally, these attributes are used to reconstruct the qp waveform, or patterns or features of the qp wave can be determined by using various pattern-recognition techniques. Some embodiments provide a system that uses software, embedded hardware or firmware to carry out the above-described method. Some embodiments use a computer-readable medium to store the data structure and/or instructions to execute the method.

Abstract: A method for manufacturing an equalizer used to compensate a digital signal passed by a transmission line, in which the digital signal can be presented as a frequency-domain function. The method includes measuring a the transmission line scattering-parameter; performing an integration and a differentiation about the transmission line scattering-parameter, the frequency-domain function, the ideal gain, and an equalizer scattering-parameter to get the component impedances of the equalizer; and manufacturing the equalizer circuit with the derived component impedances.

Abstract: Illustrative embodiments provide systems, applications, apparatuses, computer software program products, and methods related to identification of electrical appliances by electrical characteristics.

Abstract: The invention relates to a method for determining the humidity and/or density of a dielectric material in a resonator that is filled with said material and that contains a transmitter and a receiver. According to said method: the transmitter emits a signal; a resonance curve of the filled resonator is scanned in stages, whereby respective signal intensity values (Ui) are measured at different frequencies (fi); the resonant frequency (frm) and the bandwidth (BWm) are determined for the filled resonator from measured points (fi/Ui); and the humidity (?) and/or density (?) of the material are calculated by solving a second system of equations (G2), containing the resonant frequencies (fr0, frm) and bandwidths (BW0, BWm) of the empty and filled resonators and known calibration coefficients (ar1, ar2, br1, br2, cr1, cr2, abw1, abe2, bbw1, bbw2, cbw1, cbw2) of said resonator. The aim of the invention is to provide a method for determining the humidity independently of the density in a rapid, precise manner.

Abstract: According to an inventive scheme for introducing a watermark into an information signal, the information signal is at first transferred from a time representation to a spectral/modulation spectral representation). The information signal is then manipulated in the spectral/modulation spectral representation in dependence on the watermark to be introduced to obtain a modified spectral/modulation spectral representation, and subsequently an information signal provided with a watermark is formed based on the modified spectral/modulation spectral representation. An advantage is that, due to the fact that the watermark is embedded and/or derived in the spectral/modulation spectral representation or range, traditional correlation attacks as are used in watermark methods based on a spread-band modulation cannot succeed easily.

Abstract: Input signals are electronically watermarked using an uneven or non-uniform sampling rate. The uneven or non-uniform sampling may be pseudo-random. The uneven or non-uniform sampling meets the Nyquist criterion so that aliasing and loss of content are avoided. The resulting sampling pattern in the sampled data is detectable by a comparison with the original source data.

Abstract: A method for improving bandwidth of an oscilloscope involves, in preferred embodiments, the use of frequency up-conversion and down-conversion techniques. In an illustrative embodiment the technique involves separating an input signal into a high frequency content and a low frequency content, down-converting the high frequency content in the analog domain so that it may be processed by the oscilloscope's analog front end, digitizing the low frequency content and the down-converted high frequency content, and forming a digital representation of the received analog signal from the digitized low frequency content and high frequency content.

Abstract: Provided are an apparatus and method for determining a diameter of a reflector antenna.

Abstract: A novel method for diagnosing problems with a valve actuator or other rotary equipment. Frequency analysis is performed upon speed, position, torque, thrust, or vibration data. Speed or position data may be provided by a rotary encoder.

Abstract: In-system signal monitoring using an integrated circuit such as a programmable logic device is described. An analog-to-digital converter is disposed in the programmable logic device. A sampling bridge is coupled to provide an analog input to the analog-to-digital converter and to receive first signaling of a first frequency. A signal generator is configured to provide second signaling at a second frequency which is a fraction of the first frequency. Sample window circuitry is coupled to receive the second signaling and configured to provide third signaling to the sampling bridge at least partially responsive to the second signaling and at least partially responsive to an adjustable impedance setting of the sample window circuitry. The sample window circuitry is configured to provide an adjustable sample window within a pulse-width range.

Abstract: The invention relates to a frequency measurement apparatus which is arranged in such a way as to obtain an amplitude, chord length and rotation phase angle of a voltage rotation vector by means of an integration method, and furthermore, obtain a change rate of the rotation phase angle, and a rotational acceleration change rate of the rotation vector, and measure a dynamic frequency by determining a frequency change rate for every step.

Abstract: When a sample stream is decimated, frequency components from outside of a desired frequency band are aliased into the desired band, causing interference and loss of information. Different decimating ratios result in different frequencies aliasing into the desired frequency band. A current-mode sampling mixer 800 with capacitor banks 811 and 812 that are controlled by a digital control unit 820 with a capability to integrate and decimate an RF current at different decimating ratios is able to measure the frequency spectrum with different decimating ratios. The measured frequency spectrum is then analyzed to detect the presence of interferers aliased into the desired frequency band. The interferers can then be eliminated or avoided.

Abstract: The present invention provides for disambiguating the phase of a field received from a wireless tracker in an electromagnetic (“EM”) tracking system. In a first method, a carrier wave signal is modulated with a tracking signal transmitted by an EM tracker. A time reference indicating a starting point for a particular phase of the carrier wave signal is determined and is used to determine the proper phase for the tracking signal. In a second method, the EM tracker transmits auxiliary data that includes the proper phase of the tracking signal. In a third method, the EM tracker includes a passive transponder that receives a desired phase of a tracking signal as auxiliary data in an excitation signal. In response, the EM tracker transmits the tracking signal according to the desired phase. Tracking electronics may then lock onto the proper or desired phase determined according to any of the disclosed methods.

Abstract: A load shedding system and method for controlling imbalances in a power system includes a signal generator adapted to generate a signal representative of a local system, and a modifying circuit adapted to adjust set frequencies. The system also includes a processing circuit adapted to process data received from the signal generator and modifying circuit and set load shedding priorities for the local system based on the processed data.

Abstract: A method of estimating an instantaneous frequency of a component of interest in a complex primary signal via a complex Phase Locked Loop (PLL). A complex incident signal including a complex exponential evaluated at a synthesis frequency is calculated according to a complex Voltage Controlled Oscillator (VCO) function. A complex mixed signal is calculated according to a function that includes multiplying the complex primary signal by a representation of the complex incident signal. A complex baseband signal is calculated according to a function that includes filtering the complex mixed signal such that the bandwidth of the complex baseband signal is less than or equal to the bandwidth of the complex mixed signal. A residual frequency of the complex baseband signal is calculated via a complex Phase Discriminator (PD). The synthesis frequency is modified according to a function that includes the synthesis frequency and the residual frequency, such that the residual frequency is minimized.

Abstract: A technique for generating and detecting an EM signal in the THz range involves generating EM energy having multiple modes, selecting at least two of the modes of the EM energy to provide a multi-mode EM signal, subjecting the multi-mode EM signal to mixing, and isolating a beat signal component that results from the mixing. The spacing between adjacent ones of the selected modes, i.e., the frequency difference between the modes, is in the radio frequency (RF) or microwave frequency ranges. Signals in these ranges are commonly processed using electronic circuits at room temperature.

Abstract: A frequency hopping pattern of a frequency hopping signal is detected by use of spectrogram-generating software in a digital storage oscilloscope. By using a spectrogram, a hopping pattern can be determined without having to demodulate the signal, recover the phase or frequency of the carrier, determine optimal sample timing, or determine system timing. A block of data that contains at least one repetition of the hopping pattern in analyzed with respect to known hopping patterns as well as with respect to the duration in time of the relevant symbols of that data.

Abstract: A pulsed ring oscillator circuit for storage cell read timing evaluation provides read strength information. A pulse generator is coupled to a bitline to which the storage cell to be measured is connected. The storage cell thereby forms part of the ring oscillator and the read strength of the storage cell is reflected in the frequency of oscillation. A pulse regeneration circuit is included in the ring so that the storage cell read loading does not cause the oscillation to decay. Alternatively, a counter may be used to count the number of oscillations until the oscillations decay, which also yields a measure of the read strength of the storage cell. The pulse generator may have variable output current, and the current varied to determine a change in current with the storage cell enabled and disabled that produces the same oscillation frequency. The read current is the difference between currents.

Abstract: One or more median filter circuits are used to filter radio link control measurements corresponding to one or more radio link parameters of interest, such as received signal quality or round trip delay measurements, such as might be used by a base station to trigger mobile station handoff. As such measurements are particularly susceptible to measurement outliers arising from rapid but short-lived changes in radio link propagation paths, for example, the application of median filtering to such measurements is particularly advantageous. That is, by operation of median filtering, which is a non-linear filtering process, outliers in a stream of control measurements, such as are caused by instantaneous changes in channel fading or other propagation phenomena, are discarded rather than averaged in with the other measurements. Non-linear filtering as implemented by exemplary median filtering does not impair or otherwise limit the bandwidth of the underlying control measurements.

Abstract: The apparatus for analyzing a delay defect of the present invention obtains the RC of the maximal incidence among region codes (RCs) to which check circuits detecting errors caused with gradual increase in the frequency of an operational clock pulse fed to an integrated circuit belongs. The apparatus obtains information on latch in which an error is caused with the RC of the maximal incidence, with reference to a mapping table that describes the mapping relationship between an RC and a latch. The apparatus extracts a circuit portion in which an error can be captured with the region code of the maximal incidence by exhaustively tracing back circuit portions connected with each obtained latch, from the latch to the latch described in the mapping table. The apparatus gives delay defects to the input and the output pin of each of logic elements included in the extracted circuit portion, generates test patterns for detecting the given delay defects, and performs delay tests.

Abstract: A wander gamut display for perturbation analysis is created by determining from a periodic input data signal and a reference clock a frequency offset and frequency drift rate for the input signal. The frequency offset and frequency drift rate are input to respective orthogonal axes of a Cartesian display together with a wander limit bounding box that defines the wander gamut. Values that fall outside the bounding box on the display indicate wander that may result in data errors.

Abstract: A power supply apparatus for operation supplies a drive signal of a resonant frequency to a surgical instrument to drive the instrument. A recognition section recognizes a surgical instrument connected to the power supply apparatus. A setting section sets a frequency scanning condition according to the surgical instrument recognized by the recognition section. A scanning section scans for the resonant frequency of the surgical instrument on the basis of the frequency scanning condition set by the setting section.

Abstract: The invention relates to a method for error location in branched low voltage and medium voltage networks and to an evaluation network used therefor.