Abstract: An apparatus, computer program product and method of analyzing complex signals. Independent versions are generated for the complex signal, e.g., by adding multiple instances of white noise. Intrinsic mode functions (IMFs) are extracted from each of the independent versions, e.g., using Empirical Mode Decomposition (EMD). Corresponding IMFs from each independent version are combined into Ensemble IMFs (EIMFs), e.g., taking the mean of the corresponding IMFs.

Abstract: An on-chip signal waveform measurement apparatus mounted on an IC chip measures signal waveforms at detection points on the IC chip. A reference voltage generator successively generates reference voltages different from each other based on a predetermined timing signal, and Signal probing front-end circuits are mounted to correspond to the detection points, respectively, and each buffer-amplifies a voltage at each detection point, compares the buffer-amplified voltage with each reference voltage, and digitizes a comparison result into a binary digital output signal. A multiplexer time-division-multiplexes the binary digital output signals from the signal probing front-end circuits. A data processing unit calculates a judgment output probability for a detected voltage at each detection point detected by the respective signal probing front-end circuits, by counting a number of times of a predetermined binary value of the multiplexed binary digital output signal.

Abstract: Methods and systems of detecting one or more characteristics of a load are disclosed. One or more characteristics of a first signal may be detected at the output of a Radio Frequency (RF) power generator. The first signal may have a fundamental frequency. The one or more characteristics of the first signal may be sampled at a sampling frequency to produce a digital sampled signal. The sampling frequency may be determined based on a function of the fundamental frequency of the first signal. One or more characteristics of a load in communication with the RF power generator may then be determined from the digital sampled signal.

Abstract: A measured value processing circuit records measured values for a predetermined number of repeated patterns converted by an A/D converter, in a measured value memory. A calculation section calculates standard deviations of measured values for the predetermined number of repeated patterns obtained at corresponding sample times of predetermined period. A waveform processing section uses the standard deviations determined by the calculation section to generate a waveform corresponding to the input signal. A display control section displays the waveform generated by the waveform processing section, in a display section. The present invention reduces the amount of noise displayed on a display screen. A digital oscilloscope can thus display a waveform that allows the quality of an input signal to be easily evaluated.

Abstract: The system and method of determining insertion loss of a telephone line under test (LUT) determines a first insertion loss as a function of plurality of different equivalent circuit values of the LUT determined at a plurality of different frequencies of a first set of discrete frequencies. A running standard deviation (rSTD) of a predicted length d of the LUT at each frequency of a second set of discrete frequencies is determined from the predicted lengths d of the LUT at and below said frequency. A second insertion loss is determined based on the pair of adjacent discrete frequencies of the second set of discrete frequencies that have the largest difference between their rSTDs. Based on a comparison of the first and second insertion losses to an expected insertion loss, one of these insertion losses is deemed to be the actual insertion loss of the LUT.

Abstract: A micro-magnetization analysis program, method, and apparatus which can analyze transitional change of a micro-magnetization state while one of a plurality of magnetic substances such as a recording medium and a recording head is moved in an arbitrary direction. An input unit reads an analysis object model in which merely regions of a magnetic substance fixed in a space and a magnetic substance to be moved are subjected to mesh-division into minute elements and analysis conditions. A magnetic field distribution calculating unit generates a first magnetic field equation, generates a second magnetic field equation, and solves the simultaneous equations thereof.

Abstract: A method of identifying an unknown target comprising creating a density function of cepstral coefficients for a known target; receiving a signal from the unknown target; transforming the signal from a time spectrum to a frequency spectrum using a Fourier transform; transforming the frequency spectrum to a cepstrum; creating a density function of cepstral coefficients for the unknown target; and comparing the density function of the unknown target with the density function of the known target.

Abstract: A method of using a vector network analyzer (VNA) for coordinated Voltage Standing-Wave Ratio (VSWR) and Time Domain Reflectometry (TDR) measurement includes configuring the VNA for identifying discontinuities correlated to a VSWR lobe. In some embodiments, the method includes identifying a largest VSWR lobe in a frequency band of interest, using phase data associated with an S11 scattering parameter to find the correct electrical delay required to align Low Pass Step Transform data, and configuring the Low Pass Step Transform span and center time to align coherent inductive and capacitive discontinuities relative to grid lines of a TDR display. In some embodiments, the method is automated.

Abstract: In a method, computer program and system for determining an operational limit of a power transmission line, time-stamped current phasor information and voltage phasor information for a first end and a second end of the line are determined, an ohmic resistance of the line is computed from the phasor information, and an average line temperature is computed from the ohmic resistance. This allows to determine the average line temperature without dedicated temperature sensors. The average line temperature represents the actual average temperature and is largely independent of assumptions regarding line parameters.

Abstract: A real time DSO is equipped with a Digital Trigger Filter that performs high frequency rejection, low frequency rejection, AC and DC triggering. The Digital Trigger Filter includes first and second digitally implemented IIR (Infinite Input Response) Filters. A digitized Conditioned Input Signal is applied to the first IIR Filter. It has taps that provide the Trigger Signal outputs needed for high and low frequency rejection. The high frequency rejection output of the first ER Filter is essentially a low pass output (3 dB down at 50 KHz) and is also used as the digital input to the second IIR Filter, whose output is a much more aggressive suppression of high frequencies (3 dB down at 50 Hz). The AC Trigger Signal output is produced by subtracting the output of the second IIR filter from the original input to the entire Digital Trigger Filter, and the DC Trigger Signal output is simply the same as that original input. A MUX selects which Trigger Signal is applied to a Digital Trigger Comparator.

Abstract: A first test signal from a test signal source is provided to a spectrum analyzer to produce first measurement data. The test signal source is expressed by a first transfer function G(w) and the spectrum analyzer is expressed by second transfer function F(w). A second test signal is provided to the spectrum analyzer to produce second measurement data where the second test signal is derived from the first test signal by shifting the frequency by a known increment. From the first and second measurement data, the components are the same on G(w) but different on F(w). The G(w) components are cancelled by calculation using the first and second measurement data and then the second transfer function F(w) is evaluated independently of G(w).

Abstract: A device for calculating the steady state behavior of a controller includes an amount generating unit for generating the amount of deviation of the regulator, a first threshold value calculation unit that detects whether the amount of deviation of the regulator has fallen below a first threshold value and then starts a lag time delay unit, and a second threshold value calculation unit that detects whether the amount of deviation of the regulator has fallen below a second threshold value. A signal transmission unit transmits a ready message signal when the lag time delay unit has reached a predetermined lag time and the second threshold value calculation unit has detected that the amount of deviation of the regulator has fallen below the second threshold value.

Abstract: A system and method can be utilized to determine S-parameters of a network. In one embodiment a system includes an S-parameter calculator that computes the S-parameters of the network based on waveform parameters determined from single port measurements. At least one of the single port measurements corresponds to measurements at one of the plural ports while a matched load is applied to at least another of the plural ports.

Abstract: A method of analyzing the condition of a motor driven rotating system using a current waveform produced by the motor. The motor position is initially identified from the current waveform produced by the motor and more particularly, a step of identifying the segment switching of the motor is performed to identify the system position with reference to individual rotations of the motor. The current waveform is then normalized to a preselected number of data points, each rotation being described by the preselected number of data points, such that the current waveform is converted from the time domain to a spatial domain corresponding to positions of the system. Subsequently, a frequency analysis is performed to identify frequencies corresponding to characteristics of the system, including calculating a frequency dependent distribution of the normalized current waveform to determine the energy content of the waveform at particular frequencies.

Abstract: A receiver exploits unique higher order statistics of temporally dependent waveforms to classify, characterize, identify (fingerprint) and intercept a waveform within the field of view of the receiver. The method uses 4th-order non zero lag auto cumulants of the received waveform and 4th-order non zero lag auto cumulants of known waveforms to classify and characterize the signal. The receiver includes a multi-element array and does not need a priori knowledge of the transmitted signal source obtain a fingerprint.

Abstract: A method compensates for phase differences between sampled values of first and second AC waveforms. The method employs a phase angle compensation factor and sequentially samples a plurality of values of each of the waveforms. For a positive compensation factor, second sampled values are adjusted to correspond with first sampled values by employing, for a corresponding second sampled value, a preceding second sampled value plus the product of: (i) the compensation factor and (ii) the difference between the corresponding second sampled value and the preceding second sampled value. Alternatively, for a negative compensation factor, the second sampled values are adjusted by employing, for the corresponding second sampled value, the preceding second sampled value minus the product of: (i) the sum of one plus the compensation factor and (ii) the difference between the preceding second sampled value and the second sampled value preceding the preceding second sampled value.

Abstract: An oscilloscope adapter for a portable electronic device includes a hardware interface connector and a computer program memory. The memory stores computer program instructions that direct the electronic device to collect data representative of a signal from an external source and display the data as a waveform comprising individual data values as a function of time. The user may select one or more of the scales of the graph. The adapter also may include one or more of a model waveform database, a collected waveform database, an application-specific database, and a language database.

Abstract: An electric power meter measures the value of an electrical power parameter, e.g., Universal Apparent Power or Universal Power Factor, of an electrical power signal in the time domain by: calculating a first instantaneous power component as the product of an instantaneous voltage signal and an instantaneous current signal of the electrical power signal, carrying out a relative phase shift between the instantaneous voltage signal and the instantaneous current signal; and calculating a second instantaneous power component as the product of the relatively phase-shifted instantaneous voltage and instantaneous current signals. The first and second instantaneous power components are then RMS averaged to determine their respective magnitudes. Both of the calculated magnitudes are then used to determine the value of the electrical power parameter. The method can alternatively be implemented in the frequency domain to produce equivalent measurement values.

Abstract: A method for detecting extraneous matter in a fluid including the steps of applying an energy source to electrodes located in a fluid, measuring real and imaginary electrical impedance values across the electrodes for a plurality of different frequencies of alternating energy and identifying at least one characteristic of an extraneous matter in the fluid.

Abstract: An eye diagram analyzer assigns a plurality of SUT data signals to be members of a labeled group of channels. There may be a plurality of such groups. In addition to mere superposition in an (X, Y) display space of the various i-many (X, Y)-valued pixels for individual component eye diagrams associated with that group, other measured data for those pixels within a group can be merged in various different modes to produce corresponding composite eye diagram presentations. E.g., in a Normalized Signal Density Mode the number of hits at each trial measurement point is summed over all channels in the group, and then divided by the total number of clock cycles measured for the ith measurement point in that group to produce a density Di associated with the corresponding ith pixel: (Xi, Yi, Di). If Di is rendered as a color or an intensity, the resulting eye diagram includes a representation (the Di) of a normalized density of transitions at each point (Xi, Yi), relative to that group as a whole.

Abstract: An interferometric signal processing apparatus (10) producing an output signal from a first input signal (34) and a second input signal (34), the input signals (34) having substantially equal carrier frequencies, comprising a bridge (12) having a first arm (26) and a second arm (28), each arm having a first end (30) and a second end (32), the first and second input signals (34) being input to the first end (30) of the first and second arms (26, 28), respectively; a device-under-test (36) provided the first arm (26); a carrier suppressor (14) connected to the second ends (32) of the first and second arms (26, 28) to produce a carrier-suppressed signal at its output (A); an amplifier (16) arranged to amplify said carrier-suppressed signal; and a mixer (22, 24) responsive to the amplified carrier-suppressed signal and a carrier-dominated signal to produce the output signal; wherein the differential group delay between: the first end (30) of the first arm (26) and the output (A) of the carrier suppressor (14); an

Abstract: An apparatus for the improvement of AC waveform comprising means for applying a demand input waveform at an input of a circuit for power conditioning (including an inverter PWMVC or BBHCC) that is operable to provide an output waveform at an output; a feedback loop between the input and output, the feedback loop including means for sampling the output waveform (ADC1), means for subtracting a required waveform (RW) from the output waveform to produce an error waveform, means for processing the error waveform in a pre-defined manner to produce a processed error waveform (Clip1, Disc1, Att1), means for adding or subtracting the processed error waveform from Th. demand waveform to produce a revised demand waveform, and means for applying the revised demand waveform to the input of the power conditioning circuit at a subsequent time as an input demand waveform to produce a new AC output waveform at the output.

Abstract: A method of analyzing a sample waveform in the time domain. Firstly, a periodic wave, such as a sinusoidal wave, is inputted into a waveform processing module for obtaining a sample waveform. Next, a detection of a number of peaks of the sample waveform is performed. A determination is then made as to whether the period of the sample waveform is obtainable from the peaks of the sample waveform. If not obtainable, it indicates the waveform processing module is malfunctioning. If obtainable, a determination is then made as to whether the period of the sample waveform is equal to the predicted period. According to this determination, it indicates whether the waveform processing module is functioning.

Abstract: An electromagnetic wave analyzer and program which can handle non-uniform cells with smaller computation errors. A given computational domain is divided into a plurality of cells for the purpose of finite difference approximation. For each space point, a cell size identification unit identifies the uniformity of surrounding cells. When the surrounding cells are identified as being uniform in size, a first calculation unit calculates electromagnetic field components at that space point with a first calculation method. When the surrounding cells are identified as being non-uniform in size, a second calculation unit calculates the same with a second calculation method which has smaller computational errors than the first calculation method. A data output unit then outputs the calculated electromagnetic field values.

Abstract: An electricity meter includes a current sensor, an analog to digital (A/D) converter coupled to the current sensor, and a processor coupled to the A/D converter. The current sensor and the A/D converter cooperate to generate a digital current signal having a waveform representative of the current waveform on the power lines connected to the electricity meter. The processor is operable to analyze a digital current waveform signal produced by the current sensor and A/D converter to detect a rectified (DC) load. In particular, the processor perform analysis on the digital current signal to generate a peak positive current value and a peak negative current value, and then detect the presence of a rectified load coupled to the power network based on said peak positive current value and said peak negative current value.

Abstract: An intermodulation detector (11) that operates standalone or in parallel with a radio receiver (10) of a radio receiver system (100) including a receiver tuning logic module (12), and, in the case of operating standalone, provides signals conveying information about intermodulation power in the receiver frequency band, and in case of operating in parallel with a radio receiver (10), provides to the receiver tuning logic module signals conveying information about power aliasing into the frequency band to which the radio receiver is tuned.

Abstract: An amplitude modulator circuit includes a reference oscillator and an envelope modulator coupled to the reference oscillator for receiving a reference signal. A microcontroller is coupled to the envelope modulator for providing an envelope signal to the envelope modulator and a low pass filter is coupled to the envelope modulator for receiving a modulated command from the envelope modulator. An inverter is coupled to the low pass filter for receiving a low passed envelope modulated signal from the low pass filter and a transducer or amplifier is coupled to the inverter and the low pass filter for receiving an inverted low passed signal and the low passed envelope modulated signal.

Abstract: A method of operating an oscilloscope includes acquiring waveform data using a group of default acquisition parameters, analyzing the acquired waveform data in accordance with a selected one of several rule sets and deriving an optimized group of acquisition parameters. The method then proceeds by acquiring waveform data using the optimized group of acquisition parameters, and displaying the waveform data acquired using the optimized group of acquisition parameters.

Abstract: An oscilloscope adapter for a portable electronic device includes a hardware interface connector and a computer program memory. The memory stores computer program instructions that to direct the electronic device to collecting data representative of an signal from an external source and displaying the data as a waveform comprising individual data values as a function of time. The user may select one or more of the scales of the graph. The adapter also may include one or more of a model waveform database, a collected waveform database, an application-specific database, and a language database.

Abstract: Materials display innate resistance, capacitance, and inductance (RCL) properties and can therefore be distinguished in accordance with these properties. A high voltage is applied across a material, and a waveform is obtained whose rise time, frequency content, duration, and fall time represent the RCL properties of the material. The high voltage can be applied by passing air containing the material through a pair of screens held at a potential difference or by gluing a sample of the material to two rods held at a potential difference. The voltage may or may not be enough to cause the material to arc.

Abstract: A digital video signal monitoring apparatus comprises means (2,4,6) for receiving a digital video signal and extracting therefrom a plurality of digital signals, each of which comprises a plurality of successive digital sample values. The apparatus further comprises means (10) for interpolating additional digital values intermediate the successive samples of the or each extracted digital signal and means for displaying the waveform of the or each extracted digital signal as a series of discrete points corresponding to its respective digital sample values and interpolated digital values. Thus, none of the original signal information is lost in displaying a signal waveform having a substantially continuous appearance.

Abstract: A pair of resistors, having substantially equivalent resistance are arranged in series so that two data output lines of a differential data driver are connected to the ends of the series of resistors, the potentials of the two output signals ((D+)data output signal and (D−)data output signal) from the differential data driver are resistively divided to detect the sum of the potentials of the two signals. Based on the voltage of the combined signal, the acceptability of the differential signals of the differential data driver is determined.

Abstract: The present invention discloses methods and systems of measuring transmission performance characteristics, such as from an amplifier. The method comprises the steps of receiving a signal, demodulating the signal, generating an ideal signal from the demodulated signal and estimating the performance characteristic from a difference between the ideal signal and the received signal. A system for measuring a transmission performance characteristic, comprises a demodulator for demodulating a received signal, a signal generator for producing an ideal signal from the demodulated signal and a processor for estimating the performance characteristic from a difference between the ideal signal and the received signal.

Abstract: To minimize the outlay for circuit engineering in a measuring system having at least one measuring instrument for measuring power and/or power factors at least one measuring point in an a.c. voltage network, a voltage transformer device having in each case one voltage transformer for each phase of the a.c. voltage network is arranged at a voltage-detection site of the a.c. voltage network. In addition, a current transformer for each phase is arranged at each measuring point, and to connect a measuring instrument assigned is connected to the particular measuring point at a current transformer input. The voltage transformer device and all measuring instruments are interconnected via a shared data-transmission device, in which predefined information on the detected voltages is digitally transmitted to the measuring instruments.

Abstract: The present invention comprises a method and apparatus that generates a waveform consisting of an arbitrary number of frequency sweeps combined from adding and subtracting mini frequency sweeps. Optimization routines determine the best combination order of frequency sweep to minimize or maximize design criteria such as aerodynamic surface deflection or maximum command rate of the wave form. The invention allows for arbitrary output timing, or commands per second issued for the desired waveform, arbitrary starting and ending frequencies and amplitudes, arbitrary number of frequency sweep components, arbitrary frequency sweep exponent, arbitrary amplitude sweep exponent, and arbitrary waveform length. For a given frequency range and sweep exponent, amplitude range and sweep exponent, desired total waveform time and number of frequency sweep components, the algorithm can determine the optimum arrangement of the components to minimize the maximum amplitude or rate.

Abstract: A signal analyzer, method and memory medium for generating a time varying spectrum for input signals characterized by frequency components which change in time. The signal analyzer includes a source of a sequence of digital signals representative of an input signal, a processor coupled to the source, and a memory medium coupled to the processor. The memory medium stores a software program which is executable by the processor to compute the time-varying spectrum of the input signal. When the processor executes the software program, the processor is operable to first compute a Gabor transform (that is, a sampled short-time Fourier transform) of the digital signals to produce Gabor coefficients. The processor then computes a two dimensional auto-correlation of the Gabor coefficients to produce auto-correlation results. The auto-correlation results are then applied to a 2-dimensional fast interpolation filter to produce the time-varying spectrum, wherein the time-varying spectrum is a Gabor spectrogram.

Abstract: A method, a circuit arrangement and an apparatus are provided for evaluating an input data signal transmitted by load modulation. A complex data signal is derived from the input data and a mean value signal of the complex data signal is thereafter derived. A complex signal without mean value is also formed from the difference between the complex data signal and the mean value signal of the complex data signal. A first and second quadratic error signals are derived and subsequently a slope signal is derived from the first and second quadratic signals. The method also comprises deriving an information signal by comparing the imaginary part signal without mean value with a decision threshold signal. The information signal indicates whether a value of the input data signal has been generated in a loaded state or an unloaded state during the load modulation.

Abstract: Tone signal detection circuit for a receiving circuit for detecting at least one tone signal of predetermined tone signal frequency (fE) which is contained in a received analog input signal, comprising a reference signal generator (41) for generating an analog converter reference signal which consists of a reference DC (VrefDC) and a periodic reference AC (VrefAC) having a variable fundamental frequency (fG), which is superimposed on the reference DC, an analog/digital converter (11) for converting the analog input signal into a digital data stream in dependence on the analog converter reference signal (Vref); and comprising a digital control circuit (20) which adjusts the variable fundamental frequency (fG) of the reference signal (Vref) generated by the reference signal generator (42) in accordance with the predetermined tone signal frequencies (fG) of the tone signals to be detected and evaluates the digital data stream output by the digital analog/digital converter (11) for detecting a data pattern corres

Abstract: The power supply of equipment being tested for common mode noise problems is connected to a source of power with the power and neutral input terminals of the power supply isolated from the power ground. Recorded common mode noise signals are then inserted between the power supply's neutral input terminal and power ground to produce problem conditions. When the cause of the problem conditions are identified, steps are taken to eliminate the condition.

Abstract: A method of detecting an abrupt variation in a periodic electrical quantity, where a criterion for the occurrence of the abrupt variation is formed from samples of the periodic quantity. To be able to carry out such a method in such a way that the abrupt variations in the periodic quantity can be detected with a high sensitivity, the periodic quantity is weighted in an FIR filter with a transfer function with a double zero position at the nominal frequency; the output signal of the FIR filter is monitored for whether it reaches a threshold indicating that an abrupt variation in the periodic quantity has occurred.

Abstract: A portable network analyzer and method having multiple channel transmit and receive capability for real-time monitoring of processes which maintains phase integrity, requires low power, is adapted to provide full vector analysis, provides output frequencies of up to 62.5 MHz and provides fine sensitivity frequency resolution. The present invention includes a multi-channel means for transmitting and a multi-channel means for receiving, both in electrical communication with a software means for controlling. The means for controlling is programmed to provide a signal to a system under investigation which steps consecutively over a range of predetermined frequencies. The resulting received signal from the system provides complete time domain response information by executing a frequency transform of the magnitude and phase information acquired at each frequency step.

Abstract: A harmonic injection point a is set on a power line extending downstream from a harmonic measuring point b in an electric power system. The currents of interharmonics are injected to the harmonic injection point a by a current injection device. The frequencies of the interharmonics are located on both sides of the frequency of an n-th targeted harmonic in frequency spectrum and each of the frequencies is a nonintegral multiple of the frequency of a fundamental wave of an electric power transmitted by the electric power system. The current values and voltage values of the interharmonics at the harmonic measuring point are detected to thereby obtain admittance values of an equivalent circuit of a power line extending upstream from the harmonic measuring point b when the interharmonics flow therethrough. An admittance value of the equivalent circuit of the power line when the targeted harmonic flows therethrough is determined by interpolating the admittance values for the interharmonics.

Abstract: A method for identifying short circuits in a low-voltage network includes the step of determining a first envelope and a second envelope for a plurality of locus curves of a current steepness as a function of a current in a low voltage network, the first and second envelopes including all switching angles, the first envelope being determined for a lower power factor, the second envelope being determined for an upper power factor. Additionally a third envelope is determined taking into account rated-current switching operations between the lower power factor and the upper power factor. A resultant envelope is formed from a combination of the first, second, and third envelopes by overlaying the first, second, and third envelopes. The resultant envelope defines a tolerant locus curve criterion indicating a short circuit for values outside the tolerant locus curve criterion. A configuration for identifying short circuits is also provided.

Abstract: The invention provides a method of sampling precision measurement signals to achieve an accurate measurement position at a particular measurement time, such that the measurement accuracy is unaffected by the velocity of motion. The method involves sampling each signal during a predetermined sampling period such that a signal from one sensor is sampled first, a signal from a second sensor sampled second, etc., and then the signals are sampled in reverse order such that the first signal sampled is sampled last. These sampled signals are averaged and produce a precision measurement at a time measured at one-half of the sampling time. In addition, this method can be applied to the use of separate scale tracks where each scale track is alternately sampled, or alternatively, where one scale track is sampled in the middle of the sampling period of another scale track.

Abstract: The invention is a broadband network monitoring system and method. The system has one or more RF carrier generators that generate one or more generator signals, called a reference signal, each of the generator signals having a generator signal frequency. One or more RF transient detectors sense a line signal on one or more broadband lines in the broadband network. Each line signal has one or more test signals applied by a remote RF carrier generator. Each test signal has a frequency equal to one of the reference signals. Each RF transient detector senses and compares the test signal and the reference signal in various ways to produce a transient indicator when the test signal and reference/generator signal are not the same. The transient indicator indicates that there may be a perturbation or some other problem in the respective broadband line. A controller is connected to each of the RF transient detectors and controls an RF switch and an analyzer.

Abstract: An algorithm for emitter identification of a transmitting platform using microphone keyclick analysis, and a system utilizing said algorithm, wherein said algorithm processes audio signals to detect transmission activity on a radio channel in the audio frequency range, detects the boundaries of transmitter keyclicks at the beginning and end of said transmission; extracts keying envelopes from said detected keyclick boundaries; and analyzes said keying envelopes to extract features characteristic of said keyclicks. The algorithm and system then proceed to execute a decision function based on said extracted characteristic features to identify the platform of said transmitter based on the features of said keyclick. A second algorithm, which may be executed in parallel with the first by said system, processes said transmission data using a fast fourier transform, detecting gaps in said processed transmission data.

Abstract: An algorithm for emitter identification of a transmitting platform using spectral energy analysis, and a system utilizing said algorithm, wherein said algorithm processes audio signals from transmission data using a fast fourier transform, detecting gaps in said processed transmission data. It then extracts spectral features consisting of normalized energy per unit frequency from said gaps. The algorithm and system then proceed to execute a decision function based on said extracted characteristic features to identify the platform of said transmitter based on said features. A second algorithm, which may be executed in parallel with the first by said system, processes the same transmission data to detect transmission activity on a radio channel in the audio frequency range, and to detect the boundaries of transmitter keyclicks at the beginning and end of said transmission.

Abstract: Impulsive sound components in a composite sound signal are separated using wavelet analysis and sorting of wavelet coefficient sets according to statistical parameters of each respective coefficient set. Each entire coefficient set is either included or excluded from each respective separated component based on the statistical parameter. Once the impulsive sound component is isolated, it is compared with reference sound information in order to classify the sound according to its potential causes.