Abstract: Apparatus and method for refining subject activity classification for the recognition of daily activities of a subject, and a system for recognizing daily activities using the same. The refining apparatus improves the correctness of subject activity classification using daily activities of a subject, activation time information of sensors mounted on objects associated with the daily activities of the subject, and the suitability of a continuous activity pattern in relation to the daily activities. This improves the correctness of subject activity classification that becomes basic information in daily activity analysis.

Abstract: A method and apparatus for carrying out noise reduction in data regarding parameter values comprising the steps of, making a series of measurements of parameter values at times separated by predetermined time intervals, forming a plurality of successive measurements into an array of measurements, performing n successive wavelet transforms on the array of measurements to produce an array of coefficients, comparing the values of the array of coefficients to a threshold value and, selectively changing the values of said coefficients based on their relationship to the threshold, to produce an array of filtered coefficients, and performing n successive inverse wavelet transforms on the array of filtered coefficients to produce an array of filtered measurements.

Abstract: A system and method of conducting a continuous performance analysis for a system includes collecting transient performance data for a first parameter of the system and a second parameter of the system. Transfer functions are applied to the transient performance data for at least one of the first and second parameters to thereby generate phase compensated performance data representative of a steady state relationship between the first and second parameter. For each phase compensated performance datum, an estimate of the first parameter is calculated at a predetermined value of the second parameter using the phase compensated performance datum and a previously stored performance characteristic curve representative of the steady state relationship between the first and second parameters in a deterioration model extrapolation method.

Abstract: A system for evaluating the metrological characteristics of a surface of a substrate, the system including an optical substrate measurement system, a data analyzing system for analyzing data in an evaluation area on the substrate, applying feature-specific filters to characterize the surface of the substrate, and produce surface-specific metrics for characterizing and quantifying a feature of interest, the surface-specific metrics including a range metric for quantifying maximum and minimum deviations in the evaluation area, a deviation metric for quantifying a point deviation having a largest magnitude in a set of point deviations, where the point deviations are an amount of deviation from a reference plane fit to the evaluation area, and a root mean square metric calculated from power spectral density.

Abstract: A method and system for detecting wind noise are adapted to determine whether two of a plurality of sound signals acquired by a plurality of sound receiving units include wind noise.

Abstract: Provided is a semiconductor device for outputting only the necessary information from non-periodic noise information to the outside. An analysis object information extracting section specifies analysis object information used to analyze noise associated with a malfunction from the non-periodic noise information having a large amount of information and extracts only the specified analysis object information from the noise information. A communication section outputs the extracted analysis object information to the outside. Thus, the amount of the information can be reduced and the noise information can be outputted by an inexpensive communication section such as a serial communication device.

Abstract: Techniques, systems and computer program products are disclosed for providing sensor mapping. In one aspect, a method includes receiving input from a user. The received input includes at least one of motion, force and contact. In addition, a sensor signal is generated based on the received input. From a choice of data structures a data structure associated with a selected application having one or more functions is identified. The data structure indicates a relationship between the generated sensor signal and the one or more functions of the selected application. The generated sensor signal is selectively mapped into a control signal for controlling the one or more functions of the selected application by using the identified data structure.

Abstract: Embodiments for performing clutter filtering in an ultrasound system are disclosed. In one embodiment, an ultrasound data acquisition unit acquires ultrasound data from a target object for color Doppler imaging and a processing unit extracts a plurality of frequency components of the ultrasound data using an autoregressive model and computes a mean frequency component of the plurality of frequency components. The processing unit detects frequency components corresponding to a clutter signal based on the plurality of frequency components and the mean frequency component and performs clutter filtering upon the ultrasound data by using the frequency components corresponding to the clutter signal.

Abstract: A method and a device for estimating a first value of a signal formed of a series of values corresponding either to the first value or to a second value equal to the opposite of the first value, where the signal can take values other than the first and second values due to noise.

Abstract: Method and apparatus for automatically adjusting a parameter used in the display of a Doppler spectral image comprises acquiring a plurality of spectral lines of Doppler data. A subset of Doppler data is determined from the plurality of spectral lines of Doppler data. A noise characteristic of the subset of Doppler data is calculated, and a signal characteristic of the subset of Doppler data is identified. The noise and signal characteristics are compared, and a system parameter is adjusted based on a result of the comparing step.

Abstract: An optical interrogation system is described herein that can interrogate a label-independent-detection (LID) biosensor and monitor a biological event on top of the biosensor without suffering from problematical parasitic reflections and/or problematical pixelation effects.

Abstract: A capacitive ultrasonic transducer (c-MUT) comprising a silicon substrate and a transducer element which comprises transducer cells, each of which is constituted by a first electrode equipped on the top surface of the silicon substrate, a second electrode placed opposite to the first electrode with a predetermined gap therefrom and a membrane for supporting the second electrode, wherein a trench is equipped between the adjacent transducers and a conductive film is formed in the trench.

Abstract: Process controllers, methods, and systems provide for frequency control to account for the effects of periodic disturbances in the feedback signal of closed loop control systems. The frequency components of the feedback signal are determined, including the magnitude and phase of each. Waveforms for each frequency component are generated with substantially the same magnitude and substantially the opposite phase of each frequency component. The waveforms are then summed to produce a compensating waveform that is summed within the output of the control system so that the effects of the periodic disturbances are cancelled from the control system output being provided to the system under control.

Abstract: In a machine condition monitoring technique, a sensor reading is filtered using a switching Kalman filter. Kalman filters are created to describe separate modes of the signal, including a steady mode and a non-steady mode. For each new observation of the signal, a new mode is estimated based on the previous mode and state, and a new state is then estimated based on the new mode and the previous mode and state. In the steady mode, evolution covariances of both the observed signal and the rate of change of that signal are low. In the non-steady mode, the evolution covariance of the observed signal is set to a higher value, permitting the observed signal to vary widely, while the evolution covariance of the rate of change of the signal is maintained at a low level.

Abstract: An arrangement for controlling a system generated noise level such that the same is adapted to an actual ambient noise level of the system environment. Internal noise generators will thus not run at a needlessly lowered rate than actually needed. For instance, by permitting a fan to run at a generally higher speed, the system will not needlessly undergo significant internal temperature increases. By the same token, CPU performance, to the extent that it represents a noise generator, will not be needlessly throttled.

Abstract: The present invention relates to an apparatus for removing the partial discharge (PD) noise of an electrical power facility that is capable of quickly removing noise from a partial discharge signal generated from the electrical power facility such as a gas insulated switchgear (GIS) and the like, and an apparatus for detecting a partial discharge generated section.

Abstract: An optical interrogation system is described herein that can interrogate a label-independent-detection (LID) biosensor and monitor a biological event on top of the biosensor without suffering from problematical parasitic reflections and/or problematical pixelation effects. In one embodiment, the optical interrogation system is capable of interrogating a biosensor and using a low pass filter algorithm to digitally remove problematic parasitic reflections contained in the spectrum of an optical resonance which makes it easier to determine whether or not a biological event occurred on the biosensor. In another embodiment, the optical interrogation system is capable of interrogating a biosensor and using an oversampling/smoothing algorithm to reduce oscillations in the estimated location of an optical resonance caused by the problematical pixelation effect which makes it easier to determine whether or not a biological event occurred on the biosensor.

Abstract: This disclosure describes signal processing techniques that can improve the performance of blind source separation (BSS) techniques. In particular, the described techniques propose pre-processing steps that can help to de-correlate the different signals from one another prior to execution of the BSS techniques. In addition, the described techniques also propose optional post-processing steps that can further de-correlate the different signals following execution of the BSS techniques. The techniques may be particularly useful for improving BSS performance with highly correlated audio signals, e.g., from two microphones that are in close spatial proximity to one another.

Abstract: A method is presented for processing an image of a two-dimensional (2D) matrix symbol having a plurality of data modules and a discontinuous finder pattern, each distorted by “donut effects”. A resulting processed image contains an image of the 2D matrix symbol having a continuous finder pattern suitable for conventional 2D matrix symbol locating techniques, and having a plurality of data modules, each data module having a center more truly representative of intended data, and suitable for conventional 2D matrix symbol sampling and decoding. The method includes sharpening the distorted image of the 2D matrix symbol to increase a difference between low frequency and high frequency image feature magnitudes, thereby providing a sharpened image, and smoothing the sharpened image using a moving window over the sharpened image so as to provide a smoothed image, the moving window and a module of the 2D matrix code being of substantially similar size.

Abstract: The measurement apparatus includes a distortion correcting unit configured to generate a plurality of correction signals by correcting the plurality of signals using a distortion coefficient which is stored in the apparatus, a square-root of sum of squares arithmetic unit configured to calculate a square-root of sum of squares of the plurality of correction signals, a first normalizing unit configured to generate a plurality of first normalized signals by dividing each of the plurality of correction signals by the square-root of sum of squares, and a phase arithmetic unit configured to calculate the position of the object based on the plurality of first normalized signals.

Abstract: A data compression technique is disclosed for Fourier Transform Mass Spectrometry (FTMS). A statistical analysis is applied to the data in the frequency domain since most of this data is a result of randomly distributed electronic noise. A fit of the whole frequency dataset to the distribution is made to determine preliminary moments of the distribution. The data in the tail of that distribution (which is mainly the peak data) is then removed and the remaining data points are re-fitted to the distribution, to identify the moments of distribution of that remaining noise data. A noise threshold for the mass spectrum is then applied using the calculated moments. The data above the threshold is kept. The whole spectrum can be reconstituted by storing the moments of distribution along with the peak data and then regenerating the noise from those moments and adding it to the peak data.

Abstract: A method for removing sinusoidal interference signals from a noise signal. The method includes transforming a measured signal (x(t), x(?·?t)), which is composed of a limited number of sinusoidal interference signals (Ak·ej(?kt+?k), Ak·ej(?k?·?t+?k)) and a white noise signal (w(t), w(?·?t)), into a subspace containing noise components and a subspace containing interference-signal components, and forming the spectrum of only the noise signal using the subspace containing the noise components. The entire frequency range is split into several frequency bands (?), in which each measured signal (x(t), x(?·?t)) consists of a limited number (p(?)) of sinusoidal interference signals and a white noise signal.

Abstract: A signal filtering technique is designed to remove the effects of a periodic, low-frequency noise signal from a signal of interest. A signal waveform is sampled at different points of a number of consecutive periodic noise signal cycles and the collected samples are averaged to produce a corrected signal. The number of consecutive cycles in which samples are taken and averaged is inversely related to the signal amplitude such that as the signal level decreases, the number of cycles examined increases. The technique is particularly applicable to periodic signals associated with the output of Hall effect sensors in an electrical metrology environment. Improved RMS calculations are obtained for filtering low-frequency random noise from Hall sensors by averaging samples at different points of a signal cycle to create a composite desired signal cycle to facilitate other signal calculations.

Abstract: Methods and apparatus are described for measuring noise in video image processing. The described methods use horizontal and vertical variances of pixels of an image to extract noise information from the image. Silent regions in an image are considered to determine amplitude variations in the image. A smallest silent region in the image is searched by performing measurements over various block sizes. A least sum of absolute differences approach is used on both horizontal and vertical directions for finding the minimum energy of a received image signal. Using the disclosed method and processor, with a Gaussian distribution for the measured channel noise, both silent image regions, as well as edges, are equally covered.

Abstract: A method and apparatus for reducing the effects of noise on a system for measuring physiological parameters, such as, for example, a pulse oximeter. The method and apparatus of the invention take into account the physical limitations on various physiological parameters being monitored when weighting and averaging a series of measurements. Varying weights are assigned different measurements, measurements are rejected, and the averaging period is adjusted according to the reliability of the measurements. Similarly, calculated values derived from analyzing the measurements are also assigned varying weights and averaged over adjustable periods. More specifically, a general class of filters such as, for example, Kalman filters, is employed in processing the measurements and calculated values. The filters use mathematical models which describe how the physiological parameters change in time, and how these parameters relate to measurement in a noisy environment.

Abstract: In a method for providing an estimate of a head position for a disk drive, a readback signal is filtered. The readback signal includes a first position signal component corresponding to a first position pattern on a disk, and includes a second position signal component corresponding to a second position pattern on the disk. Filtering the readback signal includes using a filter determined based on statistical information regarding a noise component of the readback signal. An estimate of an amplitude of the first position signal component is generated based on the filtered readback signal, and an estimate of an amplitude of the second position signal component is generated based on the filtered readback signal. An estimate of a head position with respect to a track on the disk is generated based on the estimate of the amplitude of the first position signal component and the estimate of the amplitude of the second position signal component.

Abstract: Methods and systems are provided for filtering a pulse oximetry signal without making assumptions on the noise statistics of the signal. A pulse oximeter may receive an energy signal proportional to an amount of light detected at the sensor. The energy signal may be converted and digitally processed to estimate physiological data. The pulse oximeter may include a processor configured to execute H? filtering algorithms to estimate physiological data without requiring the variances and/or distributions of measurement and process noise in the signal. In one or more embodiments, the pulse oximeter may also be configured to execute other filtering algorithms which update H? filtering algorithms based on the pulse oximetry signal.

Abstract: A random noise signal detecting and filtering method includes: (a) calculating a difference value of data currently being input from a sensor in comparison with previous data stored in a register; (b) comparing the calculated difference value with a critical value; (c) determining whether the calculated difference value is greater than a maximum critical value or less than a minimum critical value; and (d) if the calculated difference value is greater than the maximum critical value or less than the minimum critical value, determining the current data be constitute a random signal and substituting the previous data for the current data.

Abstract: Methods and devices for determining a measurement time period, receiving a plurality of signals associated with a monitored analyte level during the determined measurement time period from an analyte sensor, modulating the received plurality of signals to generate a data stream over the measurement time period, and accumulating the generated data stream to determine an analyte signal corresponding to the monitored analyte level associated with the measurement time period are provided. Systems and kits are also described.

Abstract: A moored buoy floating at the ocean surface and anchored to the seafloor precisely measures acceleration, pitch, roll, and Earth's magnetic flux field of the buoy over a limited sampling period.

Abstract: An approach is provided for measuring, identifying, and removing at least one sinusoidal interference signal (Ak·ej(?kt+?k), Ak·ej(?·?k?t+?k)) in a noise signal (w(t), w(?·?t)). A frequency range to be measured is split into a plurality of frequency bands (?) via a Fast Fourier Transform (FFT) filter bank. For each of the frequency bands (?), an autocorrelation matrix ({circumflex over (R)}?) is determined, wherein parameters of the autocorrelation matrices ({circumflex over (R)}?) are variably adjusted based on whether the at least one sinusoidal interference signal (Ak·ej(?kt+?k), Ak·ej(?·?k?t+?k)) is to be measured, identified, or removed and further based on at least one averaging. The autocorrelation matrices ({circumflex over (R)}?) are jointly utilized for one or more of measuring, identifying, or removing the at least one sinusoidal interference signal (Ak·ej(?kt+?k), Ak·ej(?·?k?t+?k)) in the noise signal (w(t), w(?·?t)).

Abstract: Noise discrimination in signals from a plurality of sensors is conducted by enhancing the phase difference in the signals such that off-axis pick-up is suppressed while on-axis pick-up is enhanced. Alternatively, attenuation/expansion are applied to the signals in a phase difference dependent manner, consistent with suppression of off-axis pick-up and on-axis enhancement. Nulls between sensitivity lobes are widened, effectively narrowing the sensitivity lobes and improving directionality and noise discrimination.

Abstract: An arrangement and method for assessing and diagnosing the operating state of a device under test in the presence of a disturbing ambient noise and for detecting, localizing and classifying defects of the device which affect its operational reliability and quality. At least two sensors monitor signals at arbitrary locations which are affected by signals emitted by defects and by ambient noise sources. A source analyzer receives the monitored signals, identifies the number and location of the sources, separates defect and noise sources, and analyzes the deterministic and stochastic signal components emitted by each source. Defect and noise vectors at the outputs of the source analyzer are supplied to a defect classificator which detects invalid parts of the measurements corrupted by ambient noise, accumulates the valid parts, assesses the quality of the system under test and identifies the physical causes and location of the defects.

Abstract: The present invention provides a burst noise canceling apparatus which can remove burst noises even in a one-time data, without the need of a large amount of memory.

Abstract: Disclosed are a method and a device for suppressing vibrations (18) in an installation comprising an actuator (14) for actuating a flap (12) or a valve (70) used for metering a gas or liquid volume flow (16), especially in the area of HVAC, fire protection, or smoke protection. Vibrations (18) of the flap (12) or valve (70) caused by an unfavorable or wrong adjustment or configuration of the controller and/or by disruptive influences are detected and dampened or suppressed by means of an algorithm (1) that is stored in a microprocessor (49). Said algorithm is preferably based on the components recognition of vibrations (46), adaptive filtering (48), and recognition of sudden load variations (50).

Abstract: A method and an apparatus for separating a composite signal into a plurality of signals is described. A signal processor receives a composite signal and separates a composite signal in to separate output signals. Feedback from one or more of the output signals is provided to a configuration module that configures the signal processor to improve a quality of the output signals. In one embodiment, the signal processor separates the composite signal by applying a first demodulation signal to the composite signal to generate a first output signal. In one embodiment, the signal processor also applies a second demodulation signal to the composite signal to generate a second output signal. In one embodiment, a phase and/or amplitude of the first demodulation signal and a phase and/or amplitude of the second demodulation signal are selected to reduce crosstalk. In one embodiment, the composite signal is obtained from a detector in a system for measuring one or more blood constituents.

Abstract: Relative noise is a single scalar value that is used to predict the maximum value of the expected noise at any point and is calculated from the measured signal and a mathematical noise model. The mathematical noise model is selected or estimated from an observation that includes statistical and/or numerical modeling based on a population of measurement points. An absolute noise for a plurality of points of the measured signal is estimated. An array of values is calculated by dividing each of a plurality of points of the absolute noise by a corresponding expected noise value calculated from the mathematical noise model. The relative noise is calculated by taking a standard deviation of a plurality of points of the array. The relative noise can be used to calculate scaled background signal noise, filter regions, denoise data, detect false positives from features, calculate S/N, and determine a stop condition for acquiring data.

Abstract: A method for automated calibration of an avalanche photodiode receiver includes measuring two values of avalanche photodiode biases at two successive times, measuring and comparing a bit error rate corresponding to each value. When the bit error rate of the second value is equal to or greater than the bit error rate of the first value, then a third value and a fourth value of avalanche photodiode bias closer together are measured. When the bit error rate of the fourth value is smaller than the bit error rate of the third value, two subsequent values as third value and fourth value are measured, and an optimum avalanche photodiode bias when the bit error rate of the fourth value is equal to the bit error rate of the third value is measured.

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 vibration detection circuit. The circuit includes an accelerometer, a combining filter, an amplifier, and an analog to digital converter. The accelerometer generates one or more signals indicative of movement along an axis. The combining filter filters a component of the one or more signals not associated with movement and combines the components of the one or more signals indicative of movement to create a combined signal. The amplifier amplifies the combined signal and creates an amplified signal. The analog to digital converter converts the amplified signal into a digital value.

Abstract: Provided is a test apparatus that tests a device under test, comprising a waveform generator that generates a test signal to be supplied to the device under test; a digitizer that measures a response signal output by the device under test; a judging section that judges acceptability of the device under test based on the measurement result of the digitizer; and a loop-back path that connects an output terminal of the waveform generator to an input terminal of the digitizer when calibration is performed for the waveform generator and the digitizer. The loop-back path includes a noise removal filter that eliminates a noise component from a signal passed therethrough; and a path switching section that connects the waveform generator to the digitizer via the noise removal filter when the digitizer is being calibrated, and connects the waveform generator to the digitizer without including the noise removal filter therebetween when the waveform generator is being calibrated.

Abstract: A method and a system for the detection and/or removal of sinusoidal interference signals in/from a noise signal transforms a measured signal (x(t), x(?·?t)) composed of a limited number of sinusoidal interference signals (Ak·ej(?kt+?k), Ak·ej(?·?k?t+?k)) and a white noise signal (w(t), w(?·?t)) into a subspace containing its white noise components and a subspace containing its interference signal components. Following this, the individual sinusoidal interference signals (Ak·ej(?kt+?k), Ak·ej(?·?k?t+?k)) are determined using an estimation method within the subspace containing the noise components. The entire frequency range is split into several frequency bands (?), in which the measured signal (x(t), x(?·?t)) consists of a limited number (p(?)) of sinusoidal interference signals (Ak·ej(?kt+?k), Ak·ej(?·?k?t+?k)) and a white noise signal (w(t), w(?·?t)).

Abstract: Method for completely specifying orientation of electromagnetic receivers dropped to the ocean bottom in an electromagnetic survey. Survey data are selected, rejecting noisy data with long offsets and data where the receiver has saturated with short offsets (61). A model is developed comprising three independent receiver orientation angles completely specifying the receiver orientation in three dimensions, and an earth resistivity model including a water layer and possibly an air layer (62). Maxwell's equations, applied to the model and the selected data, are then inverted to determine the receiver orientations (63).

Abstract: A system for the identification of sinusoidal interference signals from a noise signal is provided. The system includes a unit for the estimation (51, 52, . . . , 5NFFT) of an autocorrelation matrix ({circumflex over (R)}v) of a measured signal (x(t), x(?·?t)), composed from the sinusoidal interference signals (Ak·ej(?kt+?k), Ak·ej(?k?·?t+?k)) and the noise signal (w(t), w(?·?t)), a unit (81, 82, . . . , 8NFFT) for frequency estimation, and a unit (91, 92, . . . , 9NFFT) for power-level determination of the spectral lines associated with the sinusoidal interference signals (Ak·ej(?kt+?k), Ak·ej(?k?·?t+?k)) A Fast Fourier Transform filter bank (1) is additionally provided for the generation of several frequency bands (v) for the measured signal (x(t), x(?·?t)), composed of the sinusoidal interference signals (Ak·ej(?kt+?k), Ak·ej(?k?·?t+?k)) and the noise signal (w(t), w(?·?t)).

Abstract: A method for configuring blades of a wind turbine for low noise generation. The method includes providing at least one noise measuring device. The noise measuring device is arranged and disposed in a position to measure noise of the blades during rotation. The wind turbine is configured to include a rotational trigger, the rotational trigger being arranged to provide a signal at a predetermined rotational position of the wind turbine blades. One or more of the blades is configured with an aerodynamic modifying device. Noise level is measured with the noise measuring device during wind turbine operation. The noise produced by each of the blades is determined. The blades are configured in response to the noise determined for each of the blades. A method for measuring the noise level generated by an individual blade and a wind turbine configured for desired noise level are also disclosed.

Abstract: A signal sensing apparatus eliminating noise is provided, having at least a first class signal sensor for receiving at least a first class signal, at least a second class signal sensor for receiving at least a second class signal, a signal receiver for receiving a signal, wherein the signal comprises at least a noise; and a master-slave multiple noise eliminator for performing a multiple adaptive filter algorithm to eliminate noise in the signal by using one of the at least a first class signal or second class signal as a master signal and one of the at least a first class signal or second class signal not used as a master signal as a slave signal.

Abstract: A method and apparatus for measuring electrical signals measures an electromagnetic wave having an interference component at a center frequency and at multiple times to obtain data points. The positions of the data points on a complex plane are calculated. Chords of a circle on the complex plane, wherein the chords passing between pairs of the data points, and the circle fit to the data points are calculated. The chords are used to determine an approximate center of the circle wherein the position of the approximate center of the circle on the complex plane represents the electromagnetic wave with the interference component removed. An indication of the measured electromagnetic wave having the interference component removed is output from the apparatus.

Abstract: Computation of variance or variance of the autocorrelation over a moving window of various sizes of a signal containing noise and possibly a small digital signal provides a sensitive, frequency independent indication of the likelihood of the presence of a small pulse, chirp or even spread spectrum digital signal possibly obscured by noise or larger signals in the signal to much lower signal-to-noise ratios than previously possible. Large signals in the signal which may also obscure any small signal are removed to a different signal path from the noise and small signals by subtraction after compression and reconstruction of the large signal. The compression noise thus added to the signal may also increase sensitivity of the variance of the autocorrelation to small signals obscured by the large signals. Controlling storage in response to the computed variance or variance of the autocorrelation allows substantial avoidance or limitation of storage of signals which contain only noise.

Abstract: The present invention relates to vibration analysis and in particular, but not limited to, the derivation of multiple types of vibration signals from one vibration signal for vibration analysis. In the preferred method of the invention the vibrations of an object are measured using at least one vibration sensor, wherein the vibration sensor converts vibrations into an electrical vibration signal. The electrical vibration signal is digitized based on a first frequency, wherein the first frequency is selected from a plurality of possible frequency values. A first type of vibration signal is derived from the digitized vibration signal. A second type of vibration signal is then derived from the digitized vibration signal based on a second frequency. The second frequency is rationally determined from, and lower than, the value selected for the first frequency. The invention also provides apparatus for deriving multiple types of vibration signals from one measured vibration signal for vibration analysis.

Abstract: An evaluation device for evaluating analog measuring signals of a detector, e.g., an IR detector, includes: an analog/digital converter device for digitally converting the analog measuring signal of the detector or an analog signal derived from the analog measuring signal into a digital measuring signal; a control device for receiving the digital measuring signal; and a subtraction device. The evaluation device receives a first analog measuring signal from a first measurement and stores the digital measuring signal formed from the first analog measuring signal, and also receives a second analog measuring signal from a second measurement. The subtraction device receives the analog measuring signal of the second measurement and an analog comparison signal formed as a function of the stored digital measuring signal of the first measurement, and forms a differential signal.