Abstract: An OCT apparatus includes an OCT optical system that has a light splitter splitting light from an OCT light source to light travelling to a measurement light path and light travelling to a reference light path and a detector detecting a spectrum interference signal of measurement light guided to a subject eye through the measurement light path and reference light from the reference light path, and a processing unit that processes the spectrum interference signal to generate OCT data. The processing unit performs at least complementary processing on an overlapping region of a real image and a virtual image in OCT data based on a plurality of OCT data obtained with different optical path lengths when detecting the spectrum interference signal, and generates OCT data subjected to the complementary processing.

Abstract: Some embodiments provide a novel method for correlating configuration data received from the network manager computer with flow group records. In some embodiments, the correlation with the configuration data identifies a group associated with at least one of: (i) the source machine, (ii) destination machine, and (iii) service rules applied to the flows. The correlation with the configuration data, in some embodiments, also identifies whether a service rule applied to the flows is a default service rule. In some embodiments, the correlation with the configuration is based on a tag included in the flow group record that identifies a configuration version, and a configuration associated with the identified configuration version is used to identify the group association or the identity of the default service rule.

Abstract: A method is disclosed for processing at least a portion of an input digital image comprising rows of pixels extending in two mutually perpendicular directions over a 2D field. The method comprises defining a kernel for processing an image, the kernel comprising at least one row of contiguous elements of the same non-zero value (such rows being referred to herein as equal-valued kernel regions), the equal-valued kernel regions, if more than one, extending parallel to one another. For each pixel in at least selected parallel rows of pixels within the image portion, the cumulative sum of the pixel is calculated by adding a value of the pixel to the sum of all preceding pixel values in the same row of the image portion. The kernel is convolved with the image portion at successive kernel positions relative to the image portion such that each pixel in each selected row is a target pixel for a respective kernel position.

Abstract: Methods and corresponding apparatus for regulation, control, and management of DC-to-AC, AC-to-DC, and/or DC-to-DC switching power conversion.

Abstract: A system and method monitoring a plasma with an optical sensor to determine the operations of a pulsed RF signal for plasma processing including a plasma chamber with an optical sensor directed toward a plasma region. An RF generator coupled to the plasma chamber through a match circuit. An RF timing system coupled to the RF generator. A system controller is coupled to the plasma chamber, the RF generator, the optical sensor, the RF timing system and the match circuit. The system controller includes a central processing unit, a memory system, a set of RF generator settings and an optical pulsed plasma analyzer coupled to the optical sensor and being capable to determine a timing of a change in state of an optical emission received in the optical sensor and/or a set of amplitude statistics corresponding to an amplitude of the optical emission received in the optical sensor.

Abstract: The present invention relates to methods and corresponding apparatus for regulated and efficient DC-to-AC conversion with power quality, and to methods and corresponding apparatus for regulation and control of said DC-to-AC conversion. The invention further relates to methods and corresponding apparatus for regulation and control of AC-to-DC and/or DC-to-DC conversion.

Abstract: The present invention relates to methods and corresponding apparatus for regulated and efficient DC-to-AC conversion with high power quality, and to methods and corresponding apparatus for regulation and control of said DC-to-AC conversion. The invention further relates to methods and corresponding apparatus for regulation and control of AC-to-DC and/or DC-to-DC conversion.

Abstract: An index calculation unit calculates a periodicity determination index for determining the presence of periodicity on the basis of the differential between each segment of the frequency distribution of input numerical data and a frequency distribution in accordance with a baseline distribution provided ahead of time. A determination unit uses the periodicity determination index calculated by the index calculation unit to determine the presence of periodicity including one or more periodic components present in the numerical data.

Abstract: Systems and methods for calculating a relative temperature of a fiber-optic cable using bi-directional analysis traces with an optical time-domain reflectometer (“OTDR”). Analysis of bi-directional traces along a length of fiber-optic cable yields a scaled local backscatter coefficient of the fiber. Accordingly, an initial set of measurement data is collected at a first time interval and a base scaled local backscatter along a fiber is calculated. A subsequent set of measurement data is collected at a second time interval and a subsequent scaled local backscatter along the fiber is calculated. The exemplary systems and methods described herein determines a change in scaled local backscatter as a function of a difference between the base scaled local backscatter and at least the subsequent scaled local scaled local backscatter along the fiber, and then determines a relative temperature variation of the fiber as a function of the change in scaled local backscatter.

Abstract: An acoustic physiological monitoring system and method wherein the usability for physiological monitoring of time segments of an acoustic signal recording body sounds is determined using frequency analysis. A time segment of the acoustic signal is filtered into a target portion in a target frequency band and a non-target portion in a non-target frequency band. Energies of the target portion and the non-target portion are computed. A usability indicator for the time segment is computed using the energies. The usability of the time segment is determined using the usability indicator. A physiological parameter estimate is selectively calculated using the time segment based on the usability of the time segment. Finally, information based on the physiological parameter estimate is outputted.

Abstract: A data filtering method includes the following steps. First, m pieces of data are identified at first to mth time points of a plurality of time points, wherein a datum is not identified at an (m+1)th time point of the time points, and m is a positive integer Then, the identified m pieces of data are removed.

Abstract: Within machine vision, object movement is often estimated by applying image evaluation techniques to visible light images, utilizing techniques such as perspective and parallax. However, the precision of such techniques may be limited due to visual distortions in the images, such as glare and shadows. Instead, lidar data may be available (e.g., for object avoidance in automated navigation), and may serve as a high-precision data source for such determinations. Respective lidar points of a lidar point cloud may be mapped to voxels of a three-dimensional voxel space, and voxel clusters may be identified as objects. The movement of the lidar points may be classified over time, and the respective objects may be classified as moving or stationary based on the classification of the lidar points associated with the object. This classification may yield precise results, because voxels in three-dimensional voxel space present clearly differentiable statuses when evaluated over time.

Abstract: A waveform acquiring unit acquires a time waveform of an electromagnetic wave. The time waveform is decomposed into wavelet expansion coefficients by wavelet transform. Influence levels of the respective wavelet expansion coefficients to a spectrum are calculated. The wavelet expansion coefficients are weighted based on at least the influence levels of the wavelet expansion coefficients to the spectrum. The weighted wavelet expansion coefficients are converted into time waveforms by inverse wavelet transform. Thus, the time waveforms that holds spectrum information needed for spectroscopic analysis and has a reduced noise is provided.

Abstract: In a circuit simulation tool in a computer system having one or more computer processors and computer-readable storage, a method for characterizing a driven oscillator circuit having an oscillator coupled to a time-varying input signal includes retrieving information provided in a circuit description of the oscillator circuit. The method also includes forming a frequency-domain harmonic balance equation for the oscillator circuit using the retrieved information provided in the circuit description of the oscillator circuit. The harmonic balance equation includes a first differential operator in a frequency domain of the input signal and a product of a differential operator in a second frequency domain of the oscillator and a frequency variable of the oscillator. The frequency variable is independent of the frequency domain of the input signal. The method further includes solving the harmonic balance equation to obtain a waveform description of the oscillator circuit.

Abstract: A test and measurement apparatus, system, and method for synchronizing an acquisition or triggering system to a specific burst of interest. The subject apparatus and method triggers on varying energy content of a signal qualified by time in the presence of high-frequency input signal bursts, by using an adjustable pulse width envelope detector, disposed in the signal path of the trigger circuitry, as a digital rectifier or to otherwise process and extract an envelope signal. An RF envelope probe having an analog envelope detector among other suitable components is disclosed. A method is implemented for isolating an interval of interest in a signal under test. An envelope detector circuit produces an envelope signal from the signal. Trigger circuitry receives the envelope signal from the envelope detector, and isolates the interval of interesting in the signal under test using the envelope signal.

Abstract: A charge potential distributed over a vehicle body resulting from the contact, separation, and friction between a tire and a road surface is detected by a detecting unit provided with a sensing electrode that is disposed on the external surface of the vehicle body, a reference electrode that is disposed apart from the external surface of the vehicle body with a space therebetween, and a sensor amplifier that senses a potential between the sensing electrode and the reference electrode as a signal and amplifies the signal. And the amplitude of the charge potential detected by the detecting unit is monitored by a data processing unit, thereby making it possible to accurately identify not only the state of the road surface but also an internal pressure state of the tire, a wear state of the tire, and the like during vehicular travel.

Abstract: An on-chip timing slack monitor that measures timing slack at the end of a critical path includes a master-slave flip-flop having a tap on the Q output of the master and a logic module coupled to the flip-flop for producing a pulse whose width is a function of the slack. A pulse width shrinking delay line removes glitches on the flip-flop output and, in combination with a digital integrator and counter, also performs a time to digital conversion operation for determining a value for timing path slack. The determined value is used by a decision module for yield analysis. The monitor can discriminate a glitch from a slack pulse at the flip-flop output for any width of glitch up to one-half of a clock cycle.

Abstract: An intelligent electronic device IED has enhanced power quality and communications capabilities. The IED can perform energy analysis by waveform capture, detect transient on the front-end voltage input channels and provide revenue measurements. The IED splits and distributes the front-end input channels into separate circuits for scaling and processing by dedicated processors for specific applications by the IED. Front-end voltage input channels are split and distributed into separate circuits for transient detection, waveform capture analysis and revenue measurement, respectively. Front-end current channels are split and distributed into separate circuits for waveform capture analysis and revenue measurement, respectively.

Abstract: Disclosed is a probe for an oscilloscope comprising a multi-stage transistor amplifier that acts as an impedance transformer. Said amplifier is a d.c.-coupled emitter follower circuit that is composed of bipolar transistors or a d.c.-coupled source follower circuit which is composed of field effect transistors and the successive amplifier elements of which are dimensioned and tuned to each other in such a way that the resulting offset direct voltage between the input and the output is minimal.

Abstract: A method for classifying a signal is disclosed. The method can be used by a station or stations within a network to classify the signal as non-cooperative (NC) or a target signal. The method performs classification over channels within a frequency spectrum. The percentage of power above a first threshold is computed for a channel. Based on the percentage, a signal is classified as a narrowband signal. If the percentage indicates the absence of a narrowband signal, then a lower second threshold is applied to confirm the absence according to the percentage of power above the second threshold. The signal is classified as a narrowband signal or pre-classified as a wideband signal based on the percentage. Pre-classified wideband signals are classified as a wideband NC signal or target signal using spectrum masks.

Abstract: A method and system for using Equivalent Time Sampling to improve the effective sampling rate of sensor data, and using the improved-resolution data for diagnosis and control. Data samples from existing sensors are provided, where the sampling rate of the existing sensors is not sufficient to accurately characterize the parameters being measured. High-resolution data sets are reconstructed using Equivalent Time Sampling. High-resolution input data sets are used in a system model to simulate the performance of the system being measured. Results from the system model, and high-resolution output data sets from Equivalent Time Sampling, are provided to an estimator, which provides accurate estimation of measured quantities and estimation of quantities not measured. Output from the estimator is used for fault diagnosis and control of the system being measured.

Abstract: The objective of this patent is to describe novel methods and device systems for detecting the fault-cleared state in a shunt compensated transmission line. The methods are applicable in all types of transmission line types and faults, in any type of reclosure mechanism, and can be implemented in existing devices such as relays and not need sophisticated equipment. One application of detecting the fault-cleared state is adaptive reclosure in which case, substantial improvement in transmission system reliability and benefits in protection can be achieved.

Abstract: Motor control circuits and associated methods to control an electric motor provide a plurality of drive signal channels at the same phase, resulting in reduced jitter in the rotational speed of the electric motor.

Abstract: The present invention constitutes a method, processes, and apparatus for measurement and analysis of variables of different type and origin. In particular, the invention presents a method and apparatus for real-time signal conditioning and analysis in the presense of impulsive, or sparse interferences. The present invention overcomes limitations of the prior art by providing a novel method for identifying and discriminating between, in real time, the conditions of the signal with and without impulsive disturbances. This method can be implemented without substantial changes in the signal processing chain of a communication or data acquisition system. The present invention also overcomes the shortcomings of the prior art through the introduction of the novel SPART filters, which can replace the corresponding analog linear filters in the signal chain of a device.

Abstract: In one embodiment of the invention, a method and a system for phase noise analysis of oscillators is provided using frequency aware perturbation projection vector techniques. The method and system includes performing steady state analysis on the oscillator by generating an augmented Jacobian matrix. A transfer function for frequency deviation is extracted for the augmented Jacobian matrix for a predetermined frequency range including the oscillation frequency of the oscillator. The phase noise is predicted based on the extracted transfer function.

Abstract: A frequency mask trigger capable of triggering based on a logical combination of two or more areas of a frequency mask transforms a frame of digital data representing an input signal into a frequency spectrum having a plurality of frequency bins, with each frequency bin having a power amplitude value. A frequency mask is defined having a plurality of reference power levels, one reference power level being associated with each frequency bin. Two or more areas of the frequency mask are defined, with each mask area corresponding to one or more of the frequency bins. A violation status is determined for each mask area by comparing all of the power amplitude values within each mask area to the associated reference power level. If any of the power amplitude values within the mask area violates the associated reference power level, then the entire mask area is deemed to be violated. A trigger signal is generated when a logical combination of the violation statuses of the mask areas is satisfied.

Abstract: An apparatus and method for providing spectrum sensing. The invention accepts as inputs a spectrogram or any other time frequency representation of signals in which the resulting two-dimensional output representation provides useful characteristics or features of the original time/series signal being analyzed. The invention employs both time and frequency averaging to exploit signal persistence in either domain.

Abstract: Method and module for measuring the rate of change of frequency of a waveform related to a converter unit of a wind turbine generator, comprising: measuring an instantaneous value of said rate of change of frequency of the waveform, calculating a first filtered value of said rate of change of frequency, said first filtered value having good accuracy but low time response, and calculating a second filtered value of said rate of change of frequency said second filtered value having a good time response but low accuracy, comparing said first and second filtered values and selecting that an output value of said measured rate of change is based on said first or second filtered values depending on said comparison.

Abstract: Embodiments of a method and apparatus for variable sensing using the frequency domain are taught herein. An exposure of a system to a physical variable is determined by periodically sensing the physical variable to produce a plurality of digital samples. The plurality of digital samples is converted to respective frequency domain representations. The exposure is calculated using the frequency domain representations.

Abstract: In one embodiment, three substantially simultaneous phase waveforms may be converted into a first quadrature signal and a zero sequence signal. For each phase waveform, a power system digital frequency may be determined through analysis of the first quadrature signal (e.g., and at least one additional prior quadrature signal) while eliminating waveform phase angles from the analysis. Subsequently, demodulation of the first quadrature signal and zero sequence signal based on the power system digital frequency results in a positive sequence phasor, a negative sequence phasor, and a zero sequence phasor.

Abstract: A test and measurement apparatus, system, and method for synchronizing an acquisition or triggering system to a specific burst of interest. The subject apparatus and method triggers on varying energy content of a signal qualified by time in the presence of high-frequency input signal bursts, by using an adjustable pulse width envelope detector, disposed in the signal path of the trigger circuitry, as a digital rectifier or to otherwise process and extract an envelope signal. An RF envelope probe having an analog envelope detector among other suitable components is disclosed. A method is implemented for isolating an interval of interest in a signal under test. An envelope detector circuit produces an envelope signal from the signal. Trigger circuitry receives the envelope signal from the envelope detector, and isolates the interval of interesting in the signal under test using the envelope signal.

Abstract: A waveform acquiring unit acquires a time waveform of an electromagnetic wave. The time waveform is decomposed into wavelet expansion coefficients by wavelet transform. Influence levels of the respective wavelet expansion coefficients to a spectrum are calculated. The wavelet expansion coefficients are weighted based on at least the influence levels of the wavelet expansion coefficients to the spectrum. The weighted wavelet expansion coefficients are converted into time waveforms by inverse wavelet transform. Thus, the time waveforms that holds spectrum information needed for spectroscopic analysis and has a reduced noise is provided.

Abstract: Systems and other embodiments associated with synthetic instrumentation are presented. A reconfigurable synthetic instrumentation unit comprises an input module, with dual input/output ports and conditioning logic to condition an input signal. An RF down converter selectively down converts the conditioned input signal. A sampled RF down converter selectively samples the conditioned input signal. A pair of narrowband A/D converters are configured to convert one of the conditioned signal, the down converted signal and the sampled signal to produce a narrowband digital signal. A pair of broadband A/D converters convert at least one of the conditioned signal, the down converted signal and the sampled signal to produce a broadband digital signal. Signal processing logic selectively performs digital signal processing on the broadband digital signal or the narrow band digital signal.

Abstract: Circuitry includes a comparator to compare an input analog signal to a threshold and to output a signal that is based on the comparison; a first circuit path to receive the signal and to detect a characteristic of the signal, where the first circuit path is configured to support triggering at a first frequency; a second circuit path to receive the signal and to detect the characteristic of the signal, where the second circuit path is configured to support triggering at a second frequency that is lower than the first frequency; and a selector to select an output of the first circuit path or an output of the second circuit path.

Abstract: A signal generation method for generating an information signal F(b) by performing a Fourier transform on a signal f(a) includes the following steps: detecting the maximum peak intensity of the information signal F(b); calculating an amplitude, a phase, and a frequency of the signal f(a) corresponding to the maximum peak intensity; generating a signal by causing the signal f(a) corresponding to the maximum peak intensity to extend along an ‘a’ axis on the basis of information about the amplitude, the phase, and the frequency of the signal f(a); generating an extrapolation signal by extracting a signal in a region smaller than a1 and a signal in a region larger than a2 from the signal, where a1<a2; generating a composite signal by combining the extrapolation signal with the signal f(a) in a range from a1 to a2; and performing a Fourier transform on the composite signal.

Abstract: Method, arrangement and network node/device for estimating a quantity related to impedance in a first frequency interval, D1, of a telecommunication transmission line where the transmission line has a length d. The method involves determining a quantity related to impedance of the telecommunication transmission line for at least two frequencies, f1D2 and f2D2, in a second frequency interval D2. The frequencies f1D2 and f2D2 should fulfil the condition that the line length d times the absolute value of the difference between a line propagation constant ?(f1)D2 and a line propagation constant, ?(f2)D2, is less than ?, i.e. abs(d*?(f1)D2?d*?(f2)D2)<?. The method further involves estimating a quantity related to impedance in the first frequency interval D1 based on the determined quantity related to impedance in the second frequency interval D2, where the estimating involves the fitting of a Puiseux series to the determined quantity related to impedance in frequency interval D2.

Abstract: Collecting and analyzing spectral data can be challenging when multiple analysis instruments need to be integrated and monitored by a quality control agent within a laboratory, industrial plant, field operation, or even an aerospace environment. The spectral analysis system and method, as presented, provides improved quality control, process control, and data management through unique feedback mechanisms between all hardware and software components within an analytical environment. Through spectral analysis presented, meaningful information is extracted from a spectral signal and fed back into the spectral analysis system to enhance overall system performance. A centralized database is provided to allow multiple users the opportunity to query the database for historical spectral records that can lead to the generation of meaningful reports.

Abstract: The apparatus corrects multi-phase signals for detecting a position of an object and obtains a phase corresponding to the position of the object. The apparatus includes a correcting unit correcting the multi-phase signals with error coefficients, respectively, a phase calculating unit performing calculation for the corrected multi-phase signals to obtain the phase, a regression unit performing regression for the calculated phases to obtain reference phases, a Fourier transform unit respectively performing Fourier transform for the corrected multi-phase signals whose phases having been respectively changed into the reference phases, and an updating unit updating, using Fourier coefficients obtained by the Fourier transform unit, the error coefficients respectively corresponding to the Fourier coefficients. The updating unit updates the error coefficients if a regression error in the regression performed by the regression unit satisfies a predetermined condition.

Abstract: Provided is a measurement apparatus that measures a signal under measurement, including a strobe timing generator that sequentially generates strobes arranged at substantially equal time intervals; a level comparing section that detects a signal level of the signal under measurement at a timing of each sequentially provided strobe; a capture memory that stores therein a data sequence of the signal levels sequentially detected by the level comparing section; a window function multiplying section that multiplies the data sequence by a window function; a frequency domain converting section that converts the data sequence multiplied by the window function into a spectrum in the frequency domain; and an instantaneous phase noise calculating section that calculates instantaneous phase noise on a time axis of the signal under measurement, based on the spectrum.

Abstract: Described herein is a method and apparatus for the detection of signals in an area of interest. Three sensor channels are provided for sensing radiated emissions in an area of interest, each channel having a sensor and a processor, the three channels sensing radiated emissions in the very low frequency band, the high/very high frequency band, and the ultra high frequency band respectively. The first and third sensor channels provide input signals to the processor in the second sensor channel so that accumulated signal data can be processed to produce an input signal for a comparator. The comparator compares the input signal with data stored in a database to indicate presence of equipment having known modes of operation.

Abstract: A phasor measurement unit and method including a transducer for transduction measurement of an electrical characteristic of a current carrying element in electrical power generation or distribution systems, the transducer generating a transducer output signal representative of the electrical characteristic; an amplifier receiving the transducer output signal and generating an amplifier output signal; a filter receiving the amplifier output signal, low pass filtering the amplifier output signal, and generating a filter output signal; an analog to digital converter receiving the filter output signal and generating a digital output signal; and a processor receiving the digital output signal, calculating phasor data from the digital output signal and generating a data output signal, wherein the calculated phasor data is at least as accurate as phasor data from a phasor measurement unit or a frequency data recorder having a transducer for nontransduction measurement of the same electrical characteristic.

Abstract: A characteristic thumbprint is extracted from a data signal, the thumbprint based on statistics relating to the data signal. The data signal can be compared indirectly by matching this thumbprint against one or more reference thumbprints. The data signal may be any type of signal, including streaming digitized audio or obtained from static files. A database may contain a number of these characteristic thumbprints, and the database can be searched for a particular thumbprint.

Abstract: The present invention provides methods, apparatus, and systems of measuring frequency. The invention includes sampling a first number of full cycles of a signal at a rate based on a nominal frequency of the signal; converting the samples to digital samples; processing the digital samples to identify a first pair of digital samples with each one disposed on either side of a first zero-crossing and a second pair of digital samples with each one disposed on either side of a last full cycle zero-crossing; interpolating the first pair of digital samples and the second pair of digital samples to determine a position of the first and last zero-crossings relative to each other in time; and calculating a fundamental frequency of the signal based on the first number of full cycles sampled and the relative position of the first and last zero-crossings. Numerous additional aspects are disclosed.

Abstract: A signal processing apparatus subjects an audio signal to musical pitch analysis using different analysis techniques for the higher and lower frequencies. When an audio signal is input, a first extractor extracts a high-frequency signal, and a second extractor extracts a low-frequency signal from the audio signal. A high-frequency processor extracts pitch components from the high-frequency signal by applying the short-time Fourier transform. A low-frequency processor extracts pitch components from the low-frequency signal by dividing the low-frequency signal into a plurality of octave components. A synthesizing unit then combines the pitch components thus extracted from the high-frequency signal and the low-frequency signal and outputs the analysis result.

Abstract: A waveform analyzer includes a converter which converts a logical function, where a pair of data including a time and a value at the time is variable, created according to data sets of a time and a value of a signal waveform at the time into a second function expressed by a binary decision diagram, an acquisition unit which obtains for each of characteristic points of a reference waveform a condition representative of constraints on a relationship between time information specified by the points and a value corresponding to the time information in the signal waveform according to a value of the reference waveform at the points and a specified tolerance given to a value of the reference waveform, and a searching unit which applies the condition for each of the points to the second function to obtain a time range which meets the entirety of the conditions.

Abstract: Provided is a phase detection device which can detect a phase by using a simple configuration.

Abstract: A method and apparatus for modeling the characteristics of memristor devices. The invention provides methods and an apparatus for accurately characterizing the linear and non-linear Lissajous current-voltage behavior of actual memristor devices and incorporating such behavior into the resultant model. The invention produces a model that is adaptable to large scale memristor device simulations.

Abstract: A method of processing stratigraphic data comprising a plurality of stratigraphic features, such as horizon surfaces, within a geological volume is provided. The method includes the steps of: extending a plurality of spaced sampling traces through the volume to traverse the stratigraphic features; and assigning the stratigraphic features respective relative geological ages. On each sampling trace, the relative geological age of each stratigraphic feature traversed by the sampling trace in the direction from geologically younger to geologically older stratigraphic features is increased in relation to the relative geological age of its preceding stratigraphic feature, under the condition that each stratigraphic feature takes the same relative geological age across all the sampling traces by which it is traversed.

Abstract: A state detecting apparatus S for detecting a current operating state of an LM (linear motion) system includes an AE sensor 1 generating a detection signal Sae by detecting an AE wave elastically generated when a plurality of balls contained in the LM system revolve in a circulation portion while spinning themselves; and a signal processing unit 4 generating a parameter indicating an intensity of the AE wave based on only the detection signal Sae corresponding to an operating frequency of the ball, and uses the parameter to determine a lubrication state of the LM system. Thereby, it is possible to provide the state detecting apparatus capable of predicting failure occurrence in the LM system; providing an improved maintenance to a user of the LM system and further longer lifetime thereof; and providing a performance guarantee and an improved quality of a device or equipment manufactured using the LM system.

Abstract: Aspects of the present invention are related to systems and methods for removing spikes and/or speckle noise from a digital signal. In some embodiments of the present invention, an input signal is filtered according to a first low pass filter. The low pass filtered signal, also considered a first local-mean signal, is subtracted from the input signal, thereby producing an AC signal. A maximum of a first region associated with the AC signal and a maximum of a second region associated with the AC signal are determined. When the maximum of the first region and the maximum of the second region meet a comparison criterion, coefficients for a second low pass filter are determined. The input signal is filtered according to the second low pass filter, thereby producing a second local-mean signal, and a second AC signal is produced by subtracting, from the input signal, the second local-mean signal.