Abstract: Disclosed is a sample ingredient analysis apparatus including a first spectrum collection unit configured to radiate first light to a sample in order to generate a first spectrum and to concentrate the first spectrum, a second spectrum collection unit configured to radiate second light to the sample in order to generate a second spectrum and to concentrate the second spectrum, a data analyzer configured to receive the first and second spectra from the first and second spectrum collection units, to generate first and second spectral data based on the first and second spectra, and to calculate the first and second spectral data in order to obtain spectral data, and a data terminal configured to receive the first and second spectra data and the spectral data from the data analyzer and to display the first and second spectra and the spectral data to the outside.

Abstract: A method of self-calibrating a mass spectrometer or mass spectral data is disclosed. At least some first observed mass to charge ratios are matched with or against a comprehensive reference set of possible or predicted elemental compositions having known precise mass to charge ratios. One or more calibration parameters of a calibration routine are then adjusted so as to optimise the match between one or more of the first observed mass to charge ratios and the corresponding known precise mass to charge ratios of one or more possible or predicted elemental compositions contained within the reference set.

Abstract: Various embodiments include methods performed in receiver circuitry of a wireless communication device for demodulating wireless transmission waveforms to reconstruct data tones, which may include receiving, from a transmitter, wireless transmission waveforms that includes peak reduction tones (PRTs) that were inserted by a PRT neural network in the transmitter, and demodulating the received wireless transmission waveforms using a decoder neural network that has been trained based on outputs of the transmitter to output a reconstruction of the data tones. Further embodiments include exchanging information between the transmitter and receiver circuitry to coordinate the PRT neural network used for inserting PRTs in the transmitting wireless communication device and the decoder neural network used in the receiving wireless communication device for demodulating transmission waveforms received from the transmitting wireless communication device.

Abstract: A system 10 for controlling a drilling operation by a drill rig 12 includes a receiver 16 for receiving sensed data related to the drilling operation. A processor 18 is in communication with the receiver 16, the processor 18 processing the sensed data to estimate at least one geological property of interest of a zone 20 in which the drill rig 12 is active. The processor 18 is configured to operate as a decision engine 22 to optimize the drilling operation automatically by changing at least one drilling related parameter during the drilling operation based on the at least one geological property of interest.

Abstract: A method of simulating an effect of interactions between a device under test and a scattering object by of a hybrid over-the-air (OTA) test system is described. The method includes the steps of determining at least one radiation parameter of the device under test, wherein the at least one radiation parameter is associated with electromagnetic waves emitted by the device under test; determining an equivalent source on a Huygens surface based on the at least one determined radiation parameter, wherein the equivalent source is associated with the device under test; assigning material properties to a Huygens box confined by the Huygens surface, wherein the material properties are associated with at least one of reflection of electromagnetic waves and absorption of electromagnetic waves; and simulating an electromagnetic interaction between the device under test and the scattering object based on the determined equivalent source and based on the assigned material properties.

Abstract: The disclosure relates to a test and measurement instrument. The test and measurement instrument comprises a digitizer for digitizing an analog input signal, thereby generating a digitized input signal. The test and measurement instrument also has a digital trigger for detecting a trigger event in the digitized input signal. The test and measurement instrument also comprises an acquisition memory for acquiring the digitized input signal at least segmentally upon a first trigger event detected by the digital trigger. The acquisition memory is configured to acquire a first signal segment prior to the first trigger event. The acquisition memory is further configured to acquire a second signal segment starting at the first trigger event. The length of the second signal segment is dynamically adjustable. Moreover, a method of analyzing an input signal by a test and measurement instrument is described.

Abstract: A portable radio (100) provides a voice control feature which advantageously enables radio users to perform talk group changes by using voice as an input medium to the radio device. Activation of a voice control button (110) and verbal entry of a valid talk group control command enables a change in talk group. The portable radio (100) comprises a controller (102) having a code plug (120) pre-programmed with a plurality of talk group alias names, and an automatic speech recognition (ASR) engine (118) providing voice control entry detection to the portable radio. The controller (102) enables a change in talk group in response to the ASR engine (118) detecting that the voice control entry is a valid talk group control command. Shortened audible confirmations of talk group change are generated using the alias names.

Abstract: Generally, the present disclosure is directed to systems and methods that generate augmented training data for machine-learned models via application of one or more augmentation techniques to audiographic images that visually represent audio signals. In particular, the present disclosure provides a number of novel augmentation operations which can be performed directly upon the audiographic image (e.g., as opposed to the raw audio data) to generate augmented training data that results in improved model performance. As an example, the audiographic images can be or include one or more spectrograms or filter bank sequences.

Abstract: Repairing a model comprising a plurality of interrelated parameters defining a dynamic behavior of a simulated interactive object in an interactive computer simulation when inputs are provided on tangible instrument(s) of an interactive computer simulation station. An expected frequency response function is obtained between each of the parameters of the model and each of instruments. Discrepancy measurement(s) are identified between the expected frequency response function and an actual frequency response function obtained from a frequency sweep of the model. At least one target parameter is identified as a potential cause of the discrepancy measurement(s).

Abstract: A calibration data acquisition unit (a) acquires Q optical spectra and S evaluation spectra, (b) extracts R subsets from a set of the Q optical spectra, (c) performs independent component analysis in which component amounts in each sample treated as independent components on each of R subsets so as to acquire R×N component calibration spectra, (d) obtains an inner product value between the R×N component calibration spectrum and an evaluation spectrum, (e) selects a component calibration spectrum for which a correlation degree between a component amount for the target component and the inner product value is the maximum as the target component calibration spectrum from among the R×N component calibration spectra, and (f) creates a calibration curve by using the target component calibration spectrum.

Abstract: A detector (110) for determining a position of at least one object (118) is disclosed. The detector (110) comprises: at least one optical sensor (112), the optical sensor (112) being adapted to detect a light beam (150) traveling from the object (118) towards the detector (110), the optical sensor (112) having at least one matrix (152) of pixels (154); and at least one evaluation device (126), the evaluation device (126) being adapted for determining an intensity distribution of pixels (154) of the optical sensor (112) which are illuminated by the light beam (150), the evaluation device (126) further being adapted for determining at least one longitudinal coordinate of the object (118) by using the intensity distribution.

Abstract: A processor calculates, from image data, a plurality of first coefficients corresponding to different frequencies using a Fourier transform and stores first frequency domain data, from which first coefficients whose magnitude is below a threshold have been excluded, in a memory. The processor also calculates, from kernel data, second coefficients of frequencies corresponding to the first coefficients indicated by the first frequency domain data using a Fourier transform and stores second frequency domain data in the memory. The processor uses the first frequency domain data, the second frequency domain data, and an inverse Fourier transform to generate a feature map indicating a result of applying the kernel data to the image data.

Abstract: Providing predictive data predicting data values for a historical dataset. The method facilitates improving the accuracy of the predictive data by identifying for a user, and allowing the user to select ancillary datasets that can be evaluated, using a predictive evaluation, together with a historical dataset to improve the accuracy of the predictive data. A user interface is provided to a user. The user interface identifies one or more ancillary datasets. The ancillary datasets are identified to the user based on the ancillary datasets meeting a threshold condition to a historical dataset. The ancillary datasets are selectable by the user in the user interface. User input is received at the user interface selecting one or more of the ancillary datasets. A predictive dataset is displayed to the user. The predictive dataset is determined by predictive evaluation of the historical dataset and the one or more selected ancillary datasets.

Abstract: A system for determining a signal source position and velocity, and methods for manufacturing and using same are provided. An exemplary method includes determining a signal source position and velocity by performing a direction analysis on a plurality of audio signals and performing an intensity analysis on the audio signals. Another exemplary method includes determining that a signal source is on a collision course with a moving platform and providing an instruction for altering the course of the moving platform to avoid a collision with the signal source. An exemplary system includes an acoustic sensing system, having a primary microphone array, a secondary microphone, and a processing device for determining a signal source position and velocity by performing a direction analysis on a plurality of audio signals and performing an intensity analysis on the audio signals.

Abstract: A method of detecting a sound event includes receiving sound signals using one or more directional microphones, extracting a time interval of each of the sound signals, extracting time information and an azimuth of a sound event included in the sound signals during the extracted time interval, mixing the sound signals received from the directional microphones using the extracted time interval, and determining a direction of the sound event generated at a specific time from a mixed sound signal obtained through the mixing using the extracted time information and azimuth of the sound event.

Abstract: Methods, systems, and computer-readable media are disclosed for compression of sequencing data. One method includes receiving waveform data associated with a chemical event occurring on a sensor array, the waveform data including a plurality of time-based waveforms of a corresponding plurality of locations of the sensor array; converting, by at least one processor, each time-based waveform of the waveform data into a frequency-domain spectrum; generating, by the at least one processor, a key frame based on a plurality of the frequency-domain spectrums; calculating, by the at least one processor, for each of the frequency-domain spectrums, a difference between the frequency-domain spectrum and the key frame; and encoding, by the at least one processor, each calculated difference between the frequency-domain spectrum and the key frame.

Abstract: Methods and apparatus to detect spillover in an audience monitoring system are disclosed.

Abstract: A preparative separation chromatograph system having a column for temporally separating components in a sample and for discharging an eluate fluid with the components, a detector for obtaining an absorbance spectrum of the eluate fluid, and a fraction collector for continuously creating a chromatogram. The system further includes: a peak section determiner; a differential value determiner for calculating a differential spectrum value and for determining whether or not the absolute value of the differential spectrum value is equal to or less than a predetermined value; and a fraction collector controller for controlling the fraction collector so as to fractionate the eluate fluid during a period of time for which it is determined that the chromatogram peak of the target component is present and for which it is also determined the absolute value of the differential spectrum value is equal to or less than the predetermined value.

Abstract: Methods and apparatus to detect spillover in an audience monitoring system are disclosed. An example method includes sampling a first audio signal received by a first microphone. A second audio signal received by a second microphone is sampled. The second microphone is separated from the first microphone by a first distance. A time delay between receipt of the first and second sampled audio signals is calculated. Whether the time delay is within a threshold time difference is determined. When the time delay is within the threshold time difference, the media is identified as local media. When the time delay exceeds the threshold time difference, the media is identified as spillover media.

Abstract: A hemispherical scanning optical scatterometer and method for its use for measuring scattered radiation, with a reflected scatter measurement laser, and/or a transmitted scatter measurement laser, an array of optical detectors, a computer controlled system to rotate the array of optical detectors, an electronic system, a computer interface and a computer for processing the signal.

Abstract: According to an exemplary embodiment of the present disclosure, apparatus and method can be provided for generating information for at least one structure. For example, using at least one first arrangement, it is possible to receive at least one first radiation from the at least one structure and at least one second radiation from a reference, and interfere the first and second radiations to generate at least one third radiation. Further, with at least one second arrangement, it is possible to generate spectroscopic data as a function of the at least one third radiation, and reduce at least one scattering effect in the spectroscopic data to generate the information. In addition or as an alternative, according to a further exemplary embodiment of the present disclosure, it is possible to classify a type of the structure based on the spectroscopic data to generate the information.

Abstract: Provided is a noise identifying apparatus and noise identifying method, allowing automatic identification of whether or not a measured noise has been influenced by a non-object noise, using a simple system. Apparatus includes a sound detection unit, including plural microphones and/or particle velocity sensors; a sound source direction specifying unit, specifying an instantaneous direction of a sound source for each unit time, on the result of detection by the sound detection unit; a variation degree calculating unit, calculating a variation degree of the plural instantaneous directions specified by the sound source direction specifying unit for a prescribed period set longer than the unit time; and a non-object noise determining unit, determining the existence/absence of a non-object noise having influenced the measurement of an object noise taken as an object to be measured, coming from a noise source, on the variation degree calculated by the variation degree calculating unit.

Abstract: A method of processing a plurality of packaged electronic chips being connected to one another in a common substrate is provided, wherein the method comprises etching the electronic chips, detecting information indicative of an at least partial removal of an indicator structure following an exposure of the indicator structure embedded within at least a part of the electronic chips and being exposed after the etching has removed chip material above the indicator structure, and adjusting the processing upon detecting the information indicative of the at least partial removal of the indicator structure.

Abstract: A method and electrical system for controlling the power supply of an electric motor, in particular the electric motor of a vehicle that can be electrically driven, includes a control device that controls the power supply of the electric motor by an energy store. The energy store comprises a plurality of modules that are exposed to stress due to repeated charging and/or discharging and undergo an aging process as a result of said stress. In order to decouple the service life of the energy store from the service life of a vehicle, for example, the control device controls the charging and/or discharging of at least two modules differently such that said modules exhibit a stress difference so as to selectively reduce the aging process of the module being exposed to less stress.

Abstract: A real-time spectrum analyzer for measuring time domain data sampled from an input signal includes a processing unit and a density histogram memory unit. The processing unit includes an FFT engine, a frequency mask detector and a frequency mask gate. The FFT engine performs FFTs on the sampled time domain data to provide FFT spectra, each FFT spectrum including multiple FFT points. The frequency mask detector determines whether each FFT point in each spectrum meets a trigger condition, and generates gate control signals corresponding to the FFT spectra based on the determinations. The frequency mask gate receives the FFT spectra and the gate control signals, and outputs only select FFT spectra that contain at least one FFT point that meets the trigger condition in response to the corresponding gate control signal. The density histogram memory unit stores the select FFT spectra for generating in a density histogram.

Abstract: The present invention provides a method and associated apparatus providing a signal metric for a transmitter of a communication system including: accumulating a plurality of power terms, each power term corresponding to a product of one of symbol amplitudes and one of scaling factors; and calculating the signal metric according to the accumulated power terms.

Abstract: The present invention provides an in vitro method for determining the glycemic index values for various food products. The present invention provides an accurate and inexpensive in vitro method for determining the glycemic index of a wide variety of both food ingredients and finished food products.

Abstract: Disclosed herein are a self-oscillation circuit having a means for eliminating a quadrature error and a method for eliminating a quadrature error using the circuit. The self-oscillation circuit having a means for eliminating a quadrature error according to an exemplary embodiment of the present invention includes: a voltage converter converting a current signal from the gyroscope sensor into a voltage signal, a signal magnitude detector measuring a magnitude of a quadrature error signal included in an output signal from the voltage converter, and a quadrature error eliminator generating a signal which has the same phase as the output signal from the voltage converter and the same magnitude as a signal measured by the signal magnitude detector, based on an output signal from the signal magnitude detector and the output signal from the voltage converter.

Abstract: Aspects of the invention provide systems and methods for using ballast sensors to detect rock fall events in a vicinity of railway tracks or similar roadways or tracks. The ballast sensors are spaced apart from the tracks. Particular embodiments permit the use of signals from the ballast sensors to discriminate rock fall events from other types of events and to detect the hypocenter of a rock fall event.

Abstract: An arc fault detection circuit includes a current sensing circuit coupled to a line conductor carrying a current. The current sensing circuit operates to sense current and output data indicative of the sensed current. A processing circuit implements a frequency transform algorithm to transform the output data to frequency data in a low frequency range and with a high spectral resolution where a minimum short time observation window is concerned. The processing circuit identifies an arc fault condition on the line conductor by identifying differences in said frequency data between at least two subsequent observation windows and identifying characteristics which exceed thresholds.

Abstract: A time-interleaved RF triggering method and system on a test and measurement instrument includes an acquisition component that samples a waveform, which is converted into an amplitude, phase, frequency, in-phase (I), and quadrature (Q) waveform, any of which can be used for triggering an RF digital trigger, including triggering that uses demodulation and/or decoding of the down-converted complex IQ data samples for a given protocol. Aliasing caused by subsampled data in each of the interleaved acquisition components is cancelled out using a fractional time-shift filter.

Abstract: A tension/speed measuring device comprises a laser driver for driving the oscillation of a semiconductor laser, and a counter for counting interference waveforms included in the output of a photodiode for converting the output of the semiconductor laser into an electrical signal. The counter measures the periods of interference waveforms during a measuring interval, where a frequency distribution for the periods of the interference waveforms during the measuring interval is generated from the measuring results, where a class value wherein the product of the class value and the frequency is a maximum is used as a representative value D0 at the periods of the interference waveform, to calculate a total Ns of the frequencies of the classes that are less than 0.5 times the representative value T0 and to calculate a total Nwn of the frequencies of the classes that are equal to or greater than (n+0.5) times the representative value T0 and less than (n+1.

Abstract: The frequency-mask trigger unit comprises n trigger machines, where n?2, in order to evaluate a total of n signal paths. In this context, the n trigger machines are connected to an evaluation unit. For this purpose, at least one trigger range is transferred to the n trigger machines. Moreover, a plurality of result vectors of a signal under analysis transformed into the frequency domain are transferred via the n signal paths to the n trigger machines. Finally, each of the n trigger machines checks whether at least one of the plurality of result vectors of the signal under analysis transformed into the frequency domain infringes the at least one trigger range.

Abstract: A computer-implemented method, system, and/or computer program product monitors operational conditions of a cargo ship. A baseline composite vibration pattern is established from readings generated by multiple smart sensors. Each of the multiple smart sensors is a uniquely-identified smart sensor that has been affixed to one of multiple intermodal shipping containers that have been loaded onto a cargo ship, and each smart sensor includes a vibration sensor for detecting mechanical vibration. Subsequent readings are then taken from the multiple smart sensors to generate a new composite vibration pattern. In response to the new composite vibration pattern being different from the baseline composite vibration pattern, the new composite vibration pattern is matched with a known composite vibration pattern in order to identify a cause of the new composite vibration pattern.

Abstract: A method is disclosed for triggering upon signal events occurring in frequency domain signals. The method includes repeatedly sampling a time-varying signal and generating a plurality of digital frequency domain spectrums based on the samples of the time-varying signal. A frequency domain bitmap for the time-varying signal is repeatedly updated via application of the digital frequency domain spectrums. The method further includes selecting a portion of the frequency domain bitmap, determining a signal occupancy in the selected portion, and triggering a capture of the time-varying signal based on and in response to the occupancy determination for the selected portion of the bitmap.

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: Disclosed is an aerial surveying system for collecting electromagnetic spectrum data. Spectrally tuned antennas are used on an airplane to prefilter the data in accordance with spectral frequency bands. The data is sequentially sampled using an antenna switching device, band pass filtered and downconverted to an intermediate frequency. High speed vector signal analyzers and digitizers create frequency spectral data and I and Q temporal data. The collected data is recorded and compressed using any desirable compression technique, including video compression. Data analyzers analyze the data and display the data on a GIS map.

Abstract: A method is disclosed for triggering upon signal events occurring in frequency domain signals. The method includes repeatedly sampling a time-varying signal and generating a plurality of digital frequency domain spectrums based on the samples of the time-varying signal. A frequency domain bitmap for the time-varying signal is repeatedly updated via application of the digital frequency domain spectrums. The method further includes selecting a portion of the frequency domain bitmap, determining a signal occupancy in the selected portion, and triggering a capture of the time-varying signal based on and in response to the occupancy determination for the selected portion of the bitmap.

Abstract: A method for monitoring the function of a sensor module including sensor which generates a measurement signal for a physical quantity to be determined and applies the measurement signal to an output terminal in an unchanged form or in processed form. In addition, a test signal is generated whose spectrum lies outside the spectrum of the measurement signal. The test signal is supplied at a place in the sensor from which it reaches the output terminal in unchanged form or in processed form only in the case of a functional sensor. An output signal present at the output terminal is compared with the test signal and a diagnosis signal is generated, which indicates whether the test signal is present at the output terminal. The test signal is filtered out of the output signal and the remaining signal is applied as the measurement signal at an output of the sensor module.

Abstract: An AC impedance measuring device includes: a signal generator configured to provide a first signal on which a period signal is superimposed to a DUT; a Fourier transform unit configured to perform Fourier transform on current data and voltage data output from the DUT using a transformation window while sequentially shifting a start time of the transformation window, thereby obtaining a plurality of Fourier transform data strings of the voltage data and the current data; a difference sequence calculator configured to sequentially calculate a first difference sequence of the Fourier transform data strings of the voltage data and a second difference sequence of the Fourier transform data strings of the current data; and an impedance calculator configured to calculate an impedance of the DUT based on a ratio of the first difference sequence and the second difference sequence.

Abstract: Systems, methods, and computer-readable media for detecting signals are provided. A method comprises determining a time-frequency representation for a received signal and partitioning the time-frequency representation of the received signal into a plurality of time-frequency partitions. The method further comprises determining an energy (e.g., a spectral energy) for each of the plurality of time-frequency partitions and detecting one or more signals within the received signal based on the energy (e.g., the mean spectral energy distribution) of the time-frequency partitions. In some embodiments, multiple signals received simultaneously within an input signal may be detected in unknown noise conditions.

Abstract: A photoplethysmography apparatus and method is provided for high resolution estimating of Time-Frequency Spectra (TFS) and associated amplitudes using Variable Frequency Complex Demodulation (VFCDM), in a two-step procedure using a Time-Varying Optimal Parameter Search (TVOPS) technique to obtain TFS, followed by VFCDM to obtain even greater TFS resolution and instantaneous amplitudes associated with only specific frequencies of interest, via the combined TVOPS and VFCDM.

Abstract: A display method and apparatus provides an easy to interpret presentation of multiple channel data, in the form of columns where the height of the column represents the relative measurement. A threshold line provides an indication of whether the measurement is above or below the threshold. Greater detail and numeric measurement values can be displayed for individual channels while the multiple channel display is in view.

Abstract: Various methods and systems are provided for monitoring and analysis of electrical components. In one embodiment, a method includes obtaining raw radio frequency (RF) component data associated with an electrical component, cross-correlating the raw RF component data with a synchronized pseudo-random sequence (PRS) signal injected into the electrical component to determine a correlated impulse response, and determining a condition of the electrical component based at least in part upon the correlated impulse response. In another embodiment, a system includes a signal injection system coupled to an electrical component. The signal injection system injects a synchronized PRS signal into the electrical component. A data capture device obtains raw RF component data synchronized with the PRS signal through a RF antenna. A data analysis device cross-correlates the raw RF component data with the PRS signal to determine characteristics associated with the electrical component.

Abstract: A simple, inexpensive, and fast method of establishing if a defect does or does not exist within a thick-walled solid geometry, which is especially useful to detect if such a defect, a crack, exists within a gun barrel. With further analysis, the method allows not only the identification of the defect's presence; but, a means of establishing the size thereof—which, for example, is critical to understanding if a gun tube has a defect that would warrant its being taken out of service for the safety of its crew or removed from manufacturing. The method involves creating an acoustic vibration in the particular thick-walled, solid geometry, esp. a gun barrel, and observing the vibration pattern which results.

Abstract: Continuous monitoring and fault diagnosis of rotating machinery during variable speed operation is performed using only a position feedback signal. The position sensor generates a periodic waveform having multiple pulses per revolution of the machine. A circuit is included to detect, for example, a zero crossing or edge of the periodic waveform. At each detected zero crossing or edge, the time and position of the event is stored in memory. Other data, such as the current in the motor, may also be sampled and stored in memory. Because the sampled data is triggered by repeated feature of the position feedback signal, the sampled data is in a stationary reference frame in the position domain. Frequency analysis is performed on the sampled data, and the frequency components present in either the sampled signal are analyzed to identify the presence of a fault in the rotating machinery.

Abstract: A method and apparatus for resolving individual signals in detector output data, the method comprising obtaining or expressing the detector output data as a digital series, obtaining or determining a signal form of signals present in the data, forming a transformed signal form by transforming the signal form according to a mathematical transform, forming a transformed series by transforming the digital series according to the mathematical transform, the transformed series comprising transformed signals, evaluating a function of at least the transformed series and the transformed signal form and thereby providing a function output, determining at least one parameter of the function output based on a model of the function output, and determining a parameter of the signals from the at least one determined parameter of the function output. The method may include forming the model by modelling the function output.

Abstract: A spectrometer has: Accumulation means to obtain a data set containing N data points, repeating the measurement M times to obtain M spectral data sets or time-domain data sets S1 (d1 to dN) to SM (d1 to dN), and accumulating the M spectral data sets or time-domain data sets. Means for creating sets S1 (dn) to SM (dn) of the data points contained in the M spectral data sets or time-domain data sets S1 (d1 to dN) to SM (d1 to dN). Correlation computing means for finding correlations. Computing means for finding either the product of an accumulated or anticipated spectrum.

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: Man-portable locator systems for locating buried or otherwise inaccessible pipes, conduits, cables, wires and inserted transmitters using detector arrays and stochastic signal processing and similar techniques to analyze and display multiple target objects at differing frequencies in a layered user interface (UI) are described. In one embodiment, the locator UI may be adapted to present a target plurality sorted by proximity of target conductor to the locator operator together with other useful information specifying the multiple objects, frequencies and changes in the subterranean landscape by means of a useful combination of graphical, numeric and acoustic representations.