Abstract: A measurement system and method tests for spurious emissions included in a signal transmitted from a mobile terminal in a shorter time than before. The system includes: a band division unit for dividing the measurement frequency band into a plurality of divided bands; a first spurious measurement control unit which causes a measurement device to measure the spurious emissions of the signal to be measured in each divided band and the peak power of the spear in each divided band; and a first pass/fail determination unit that determines whether or not pass determination criteria is satisfied. The first pass/fail determination unit determines whether the peak power does not exceed the threshold of the pass determination criteria in each divided band. The threshold value of the pass determination criteria is lower than the threshold of the standard determination criteria defined by the 3GPP standard.

Abstract: Provided is a sensor in which a current sensor that detects a current of a power line as a change in a magnetic field and a voltage sensor that detects a voltage of the power line using capacitive coupling are integrally formed. The transmission of signals related to substantially the same sections is omitted in order to effectively compress an output signal from the sensor and an output signal from the voltage sensor. When the amplitude and phase of a fundamental wave which are estimated from the output signal from the sensor and the amplitude and phase of harmonics are encoded, the amplitude and phase of the harmonics are relativized with a value for the fundamental wave.

Abstract: A signal receiver includes receive circuitry. The signal receiver further includes a processor coupled to the receive circuitry and configured to receive, from a filter, a stream of samples including a first set of samples. A data rate of an input of the filter may correspond to a data rate of an output of the filter. The first set of samples includes multiple samples. The processor is further configured to perform a detection operation on the first set of samples. The processor is further configured to detect a signal emitter based on the detection operation.

Abstract: A system and method sequentially measure phases of selected comb teeth of a comb signal using a local oscillator (LO) signal whose frequency and phase are changed for each sequential measurement, and adjust the measured phases to account for the change of phase in the LO signal from measurement of one selected comb tooth to the next to ascertain reference phase differences between the selected comb teeth. The measured phases of the selected comb teeth are adjusted by applying a phase offset determined from a first phase and a second phase of a pilot tone which are measured using the LO signal, respectively, before and after the frequency and phase of the LO signal change from measurement of one comb tooth to the next. The frequency of the pilot tone is maintained to be substantially the same when measuring the first phase and the second phase of the pilot tone.

Abstract: Embodiments of this invention include a test and measurement instrument and associated methods for automatically setting frequency span in a spectrum analyzer. For example, starting with a high reference level, the power level can be automatically measured for each band. If a suitable minimum power is not found in one of the bands, the reference level can be automatically and iteratively decreased until the suitable minimum power is found, or until the most sensitive power level is reached. This assures enough sensitivity to correctly determine the signal power level and not make decisions based on noise. When power on any band is greater than the predefined noise criteria, then the band having the highest power level can be selected, and the center frequency and span for the band measuring the most power can be automatically set.

Abstract: Depending on a sensor signal, a noise signal which suppresses a useful signal spectrum of the sensor signal is determined by filtering using a filter. A noise variable, which is a measure of a noise of the sensor signal, is determined depending on the noise signal. An error of the sensor signal is identified depending on the noise variable determined.

Abstract: The current invention relates, inter alia, to charge pulse amplitude and time detecting circuits, offering very low amplitude and temporal noise, and overcoming noise performance limits in charge pulse detection circuits according to prior art. Embodiments of the present invention may include a sensing device delivering charge pulses onto a sense node, an active buffer buffering the voltage on the sense node with a low impedance, a recharge device removing signal charge from the sense node, a noise filter connected to the output of the active buffer transmitting signal voltage pulses while attenuating noise from the recharge device. Additional and alternative embodiments are specified and claimed.

Abstract: Methods, systems and other embodiments associated with pre-processing a signal for spectral analysis are presented. A system for pre-processing a digital input signal includes a digital down converter (DDC), an interpolator, and a series of down samplers. The DDC modulates the digital input signal to create a down converted signal. The interpolator re-samples the down converted signal to produce a re-sampled signal. The series of down samplers produces down sampled signals. The multiplexer selects one of the digital input signal, the down converted signal, and the down sampled signals and routes the selected signal to an output line.

Abstract: A system and method for filtering an input signal with at least a first and a second octave portions is presented. A proportional bandwidth filter system includes a bandwidth reducing filter, a down-sampler, and first and second octave filters. The bandwidth reducing filter reduces the bandwidth of the input signal and the down-sampler rolls the second octave portion represented in the reduced bandwidth signal to a top octave portion of a down-sampled signal. The first and second octave filters are comprised of a plurality of proportional bandwidth filters. The first octave filter partitions and converts the first octave portion of the input signal into output signals representing the frequency spectra of the first octave of the input signal. Similarly, the second octave filter generates outputs representing the spectra of the second octave portion of the input signal represented as the top octave portion of a down-sampled signal.

Abstract: A pre-channelized spectrum analyzer utilizes a channelizer as a preprocessor for parallel-configured low-resolution spectrum analyzers so as to perform as a high resolution spectrum analyzer. The pre-channelized spectrum analyzer has a polyphase filter that channelizes a signal input and an IFFT that generates filter bank outputs derived from the channelized signal. Spectrum analyzers are in communications with the filter bank outputs so as to generate a spectral decomposition of a subset of those outputs. The spectrum analyzers each perform a window and an FFT function on a corresponding one of the filter bank subset.

Abstract: An electronic component tester characterizes electronic components such as magnetic head/media components measure performance parameters such as signal-to-noise ratio and overwrite evaluation. The electronic component tester has a tester process controller and a spectrum analyzer. The tester process controller generates calibration and control signals for the electronic component tester. The spectrum analyzer is in communication with electronic components such as magnetic head or media components to receive a response characterization signal resulting from a stimulus signal applied to the electronic components. The spectrum analyzer then determines a frequency spectrum of the response characterization signal. The spectrum analyzer is also in communication with the tester process controller for transferring the frequency spectrum to the tester process controller.

Abstract: Transmit equalization over high speed digital communication paths may be compensated in a receiver for a probe on that path. In one example, a probe input provides a signal from an electronic communications path, the signal having been processed by a transmit equalizer. A filter circuit processes the signal to compensate for the transmit equalizer, and a decoder decodes the processed signal and produces an output for use by test equipment.

Abstract: Embodiments of this invention include a test and measurement instrument and associated methods for automatically setting frequency span in a spectrum analyzer. For example, starting with a high reference level, the power level can be automatically measured for each band. If a suitable minimum power is not found in one of the bands, the reference level can be automatically and iteratively decreased until the suitable minimum power is found, or until the most sensitive power level is reached. This assures enough sensitivity to correctly determine the signal power level and not make decisions based on noise. When power on any band is greater than the predefined noise criteria, then the band having the highest power level can be selected, and the center frequency and span for the band measuring the most power can be automatically set.

Abstract: Embodiments of the invention relate to a system for extracting and analyzing radioelectric signals of interest. It includes an integer number N of channels. Each channel Vi includes a receiver linked to an analog signals digital acquisition device delivering a digital signal SNi. Each channel Vi includes a bank of polyphase filters, extracting digital signals SEi from the digital signal SNi. The digital signals SEi each have a smaller frequency bandwidth than that of the digital signal SNi. The system includes at least one extracted digital signals distribution device suitable for receiving the digital signals SEi and distributing SEi to one or more processing and storage units. The processing and storage units are suitable for the analysis, characterization and storage of the digital signals received. Embodiments of the invention apply to the system for the radio-monitoring of radioelectric emissions in real time or in deferred time.

Abstract: A small light-weight battery operated calibrator device provides a precise sine wave output for use in calibration of test equipment, such as a RF Power Meter or a Spectrum Analyzer. The calibration device includes two power levels, one ?40 dBm and one 0 dBm. The purpose of the two power levels is to obtain a slope and offset for correction of the RF power measuring device being calibrated. Operation indication LED lights are provided to indicate which of the two powers are in use, and if battery power is below acceptable levels. Miniature low power components including a crystal oscillator and a divide by 2 integrated circuit that generates a precise square wave and a low pass filter for converting the square wave into a precise sine wave allows the calibrator to be battery operated and stored as a calibration component.

Abstract: A spectrum analyzer is provided with frequency-scalable circuit architectures that extend the bandwidth of the spectrum analyzer using an array of couplers. The array of couplers is distributed along the RF signal path at one end, and interfaced to one or more frequency-translation devices such as mixers or samplers at the other. In a first architecture, a single mixer is employed with an LO signal applied to one input and coupler outputs providing RF signals to another input, with switching controlled to select one coupler's RF output to provide to the mixer. In a second architecture, a separate mixer is used, one for each coupler RF signal, with switches selecting one of the mixer IF outputs to select a desired output frequency. Both the first and second embodiments eliminate switching and its associated loss and frequency limitations from the main RF signal path to enable wideband high-dynamic-range spectrum analysis.

Abstract: A small light-weight battery operated calibrator device provides a precise sine wave output for use in calibration of test equipment, such as a RF Power Meter or a Spectrum Analyzer. The calibration device includes two power levels, one ?40 dBm and one 0 dBm. The purpose of the two power levels is to obtain a slope and offset for correction of the RF power measuring device being calibrated. Operation indication LED lights are provided to indicate which of the two powers are in use, and if battery power is below acceptable levels. Miniature low power components including a crystal oscillator and a divide by 2 integrated circuit that generates a precise square wave and a low pass filter for converting the square wave into a precise sine wave allows the calibrator to be battery operated and stored as a calibration component.

Abstract: A small light-weight battery operated calibrator device provides a precise sine wave output for use in calibration of test equipment, such as a RF Power Meter or a Spectrum Analyzer. The calibration device includes two power levels, one ?40 dBm and one 0 dBm. The purpose of the two power levels is to obtain a slope and offset for correction of the RF power measuring device being calibrated. Operation indication LED lights are provided to indicate which of the two powers are in use, and if battery power is below acceptable levels. Miniature low power components including a crystal oscillator and a divide by 2 integrated circuit that generates a precise square wave and a low pass filter for converting the square wave into a precise sine wave allows the calibrator to be battery operated and stored as a calibration component.

Abstract: This invention relates to fault detection in electrical circuits. The invention provides a method and apparatus for testing an input circuit by generating a periodic test signal having a predetermined phase and a predetermined amplitude; summing the test signal and an input signal to provide a summed signal; processing the summed signal to provide an output signal; generating an extracted test signal from the output signal; comparing the extracted test signal with a reference signal representing said periodic test signal; generating an error signal in dependence upon the result of said comparing step. The invention also provides a method and apparatus for testing a plurality of adjacent input circuits.

Abstract: A spectrum analyzer is described which comprises a mixer for mixing the conjugate complex input signal v*(t) into a base band signal x(t), and a resolution filter for narrow-band filtering the base band signal. The resolution filter has a complex, discrete impulse response using a variation parameter k0 set to compensate for the frequency overshoot determined by the group delay of the resolution filter.

Abstract: An out of band communications apparatus includes first and second data lines arranged in a differential pair. The data lines convey high speed data within a first frequency range and out of band data within a second frequency range that differs from the first frequency range. The apparatus also includes a band pass filter coupled to the first and second data lines. The filter only passes the out of band data and blocks the high speed data. The apparatus also includes a device coupled to the band pass filter and configured to at least one of transmit and receive out of band data.

Abstract: A tester module is used to perform an adjacent channel leakage ratio measurement. The tester module includes a translation block, a first filter, a re-sampler, a memory, a router, a second filter and a power detector. The translation block translates a received intermediate frequency signal to a baseband signal. The first filter compensates amplitude and phase of the baseband signal for any unflatness in host hardware used to capture the received intermediate frequency signal. The re-sampler decimates the compensated baseband signal. The memory stores the decimated compensated baseband signal. The router reroutes the stored decimated compensated baseband signal to the re-sampler. The re-sampler resamples the rerouted stored decimated compensated baseband signal to perform spectrum shifting. The second filter performs a low pass filtering operation on the resampled rerouted stored decimated compensated baseband signal.

Abstract: The level of an output signal output from a device under test is easily adjusted in order to restrain an adverse effect on a result of measuring characteristics of the device under test. A measuring device includes a characteristic measuring unit for measuring characteristics of a device under test based on the output signal output from the device under test, an attenuator for receiving the output signal and adjusting the level of the output signal before supplying it to the characteristic measuring unit, and a level setting unit for setting the degree of the level adjustment of the output signal by the attenuator so as to minimize a measurement error which is caused by the characteristic measurement unit, and changes according to the level of the output signal supplied to the characteristic measuring unit.

Abstract: A method and apparatus for estimating the changing frequency of a signal received by a satellite receiver from, illustratively, positioning system satellites is disclosed that enables a more accurate measurement of the change in frequency of that signal due to movement of the satellite receiver relative to those satellites. The system includes a PLL having a numerically controlled oscillator (NCO) and a filter of frequency estimates (FFE). In operation, an analog signal is received at the satellite receiver and the PLL tracks the changing signal frequency and outputs non-smoothed frequency estimates into the FFE. The FFE then smoothes noise in the signal to produce a more accurate smoothed frequency estimate of the input signal. Comparing multiple estimates over time allows Doppler shift of the signal frequency received by the satellite receiver to be calculated more precisely, thus resulting in more accurate satellite receiver velocity vector determinations and, hence, position measurements.

Abstract: The frequency of an adjacent channel signal is reduced by a down converter (12), wherein the signal (adjacent channel signal) in a predetermined band centered around the adjacent channel frequency passes through a band-pass filter (22). At this time, a signal out of the predetermined band among the signals output from the down converter (12) by the band-pass filter (22) passes through the filter (22). An FFT section (32) outputs the signal having passed through the band-pass filter (22) by making it correspond with a frequency so that a first power measuring section (34) is used for power measurement on the basis of only the signal in a predetermined band. Therefore, power on an adjacent signal is accurately measured upon reception of a measurement signal.

Abstract: In a signal reproduction block of a DVD reproduction apparatus, an output signal line for outputting a characteristic information signal representing a characteristic of a filter incorporated in the signal reproduction block to the outside is additionally provided on the output side of an A/D converter. In this way, it is possible to prevent an analog data signal from deteriorating during a data signal reproduction process due to a parasitic effect of the output signal line. Moreover, the filter characteristic information signal is output through the output signal line after it is convened to a digital signal by the A/D convener, thereby avoiding the deterioration the characteristic information signal and thus improving the measurement precision.

Abstract: The frequency of an adjacent channel signal is reduced by a down converter (12), wherein the signal (adjacent channel signal) in a predetermined band centered around the adjacent channel frequency passes through a band-pass filter (22). At this time, a signal out of the predetermined band among the signals output from the down converter (12) by the band-pass filter (22) passes through the filter (22). An FFT section (32) outputs the signal having passed through the band-pass filter (22) by making it correspond with a frequency so that a first power measuring section (34) is used for power measurement on the basis of only the signal in a predetermined band. Therefore, power on an adjacent signal is accurately measured upon reception of a measurement signal.

Abstract: A method and an apparatus for measuring the instantaneous frequency of FM modulated signals, includes sampling, instantaneous frequency computing, and lowpass filtering. FM modulated signal are sampled at prescribed intervals to provide digitized FM signal. The instantaneous frequency is computed by manipulating the digitized FM signal mathematically using a new mathematical equation proposed in this invention to provide the instantaneous frequency based on digitized FM signal samples. More accurate instantaneous frequency values can be obtained by filtering the computed instantaneous frequency values using a lowpass filter.

Abstract: In connection with blind source separation, proposed herein, inter alia, are: expectation-maximization equations to iteratively estimate unmixing filters and source density parameters in the context of convolutive independent component analysis where the sources are modeled with mixtures of Gaussians; a scheme to estimate the length of unmixing filters; and two alternative initialization schemes.

Abstract: A measuring device (1), for measuring the spectrum of a measured signal in several neighbouring channels (15−9-159) of a working channel (14), comprises a selective filter (9) which damps the working channel (14) more strongly than the neighbouring channels (15−9-159). Furthermore an analogue/digital converter (5) is provided which detects the filtered measured signal from all the channels to be measured (15−9-159, 14) in a parallel and broadband manner and converts the above to a digital signal. An equaliser (11) in series with the analogue/digital converter (5), equalises the digital signal with a frequency response which is the reciprocal of the frequency response of the selective filter (9).

Abstract: A method for measuring the fundamental frequency component of a fault current or voltage, including measuring a fault current or voltage signal, which includes a DC-offset, a characteristic frequency component, a fundamental frequency component, and harmonics, with a predetermined sampling period, filtering the fault current or voltage signal to remove the harmonics, removing the fundamental frequency component from the filtered fault current or voltage signal, calculating the DC-offset and the characteristic frequency component with the fault current fault current or voltage signal wherein the fundamental frequency component is removed, and determining the fundamental frequency component by subtracting the calculated DC-offset and the characteristic frequency component from the filtered fault current or voltage signal.

Abstract: A method for measuring the fundamental frequency component of a fault current or voltage, including measuring a fault current or voltage signal, which includes a DC-offset, a characteristic frequency component, a fundamental frequency component, and harmonics, with a predetermined sampling period, filtering the fault current or voltage signal to remove the harmonics, removing the fundamental frequency component from the filtered fault current or voltage signal, calculating the DC-offset and the characteristic frequency component with the fault current fault current or voltage signal wherein the fundamental frequency component is removed, and determining the fundamental frequency component by subtracting the calculated DC-offset and the characteristic frequency component from the filtered fault current or voltage signal.

Abstract: Compared with the prior art, the invention offers several extra benefits in addition to providing a dc current signal from a sensed peak current signal. First, the control switch is referenced to the ground, and therefore floating drive for the series switch in the prior art is not necessary. Second, the peak current signal is always available regardless of the status of the control switch. By separating the peak and average current signals, the converter can be better controlled and both peak current mode control and current sharing control can be optimized. Finally, referencing the peak current and average current signals to the different grounds provides freedom to implement different control schemes.

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 method and an apparatus for measuring the instantaneous frequency of FM modulated signals, includes sampling, instantaneous frequency computing, and lowpass filtering. FM modulated signal are sampled at prescribed intervals to provide digitized FM signal. The instantaneous frequency is computed by manipulating the digitized FM signal mathematically using a new mathematical equation proposed in this invention to provide the instantaneous frequency based on digitized FM signal samples. More accurate instantaneous frequency values can be obtained by filtering the computed instantaneous frequency values using a lowpass filter.

Abstract: A method and apparatus for controlling the level of molten metal in a mold for continuous casting by using a molten metal level control system incorporating a molten metal level controller in the control loop thereof, which comprises damping selectively the predetermined frequency of frequencies of periodical molten metal level fluctuations through a notch filter installed in the control loop. The control loop preferably includes the phase compensation calculation part for compensating the phase delay of the stopper opening position control signal for adjusting the amount of the molten metal to be fed to the mold. The control apparatus in the control loop comprises a molten metal level senser, an FFT analyzer, an automatic tuning device for dealing with the results of the FFT analysis, a molten metal level controller and a notch filter.

Abstract: A method and apparatus for offset detection and correction is disclosed. In an active amplifier or filter system, or any system that may suffer from unwanted offset, the invention monitors for periods when an input, i.e. reference value, may be predicted or is known. When such a period is detected, the offset detection and correction system records the offset and compares it to the known or predicted reference value. Based on the comparison the amount of offset can be determined. In one configuration, the offset is determined to be greater than or less than the reference value. A digital value is thus provided to correction logic to control an output value. This output value increments or decrements a counter. The output of the counter feeds into a digital to analog converter. The output of the digital to analog converter is provided by into the system that suffers from offset to correct or counter the unwanted offset.

Abstract: A wide band signal analyzer includes a frequency converter for converting a signal under test to an intermediate frequency signal. A narrow band signal processor receives the intermediate frequency signal and produces a first digital signal representing a first frequency band of the intermediate frequency signal and a wide band signal processor receives the intermediate frequency signal and produces a second digital signal representing a second frequency band of the intermediate frequency signal. A transfer rate decelerator decelerates the transfer rate of the second digital signal, and a digital processor processes selectively the first digital signal or the output signal of the transfer rate decelerator. A memory stores the processed output of the digital processor.

Abstract: The present invention provides a wide band IQ splitting apparatus suitable for using in a spectrum analyzer. A quadrature oscillator 30 generates a pair of quadrature signals. An amplitude and phase adjuster 32 receives the quadrature signals and adjusts the balances of the amplitude and the phase between them. An analog splitter 20 mixes an analog IF signal with the pair of quadrature signals for splitting the analog IF signal into analog I and Q signals. First and second analog to digital converters 22 and 24 convert the analog I and Q signals into digital I and Q signals, respectively. A control and processing circuit detects the imbalances of the amplitude and phase between the digital I and Q signals for controlling the amplitude and phase adjuster 32. The amplitude and phase adjuster 32 is previously calibrated. For this first calibration, the analog splitter 20 receives a first calibration signal instead of the analog IF signal.

Abstract: In a method of analyzing the spectrum of a radio communication system transmission signal having a given carrier frequency, the transmission signal is split to obtain first and second intermediate signals. A phase-shift at the given carrier frequency is applied to at least one of the intermediate signals so that at that frequency the intermediate signals have a relative phase difference of 180°. The phase-shifted intermediate signals are recombined to form a recombined signal in which the signal part transmitted at the given carrier frequency is rejected and the spectrum of the recombined signal is analyzed.

Abstract: The device for detecting an erroneous signal characteristic of a load on an internal combustion engine that includes first and second differentiators (10,16) with delay devices that generate corresponding output signals (S11, S22) from respective load signals (S1,S2); first and second magnitude-forming devices (14,17) connected with the first and second differentiators respectively to generate respective magnitude signals from the corresponding output signals (S11,S22) first and second low-pass filters (15, 18) connected with the first and second magnitude-forming devices respectively to generate first and second DC voltage signals (MW1,MW2); a subtracting device (19) for subtracting the first and second DC voltage signals (MW1,MW2) from each other to generate a difference signal (D); and comparison devices (20,23) for generating a first error signal or a second error signal when the difference signal (D) is greater than a predetermined threshold (SW1) or less than a negative of the predetermined threshold (&

Abstract: A method, and apparatus for accomplishing the method, for determining the frequency of an RF signal that operates by sequentially applying a received RF signal to sequentially selected individual filters having predetermined frequency pass bands and comparing the magnitudes of the filtered and unfiltered RF signals. The frequency of the RF signal is determined as being within the predetermined frequency pass band of a filter that outputs a largest magnitude output signal relative to the magnitude of the RF signal. Signals of insufficient magnitude are not processed by the system.

Abstract: A method and apparatus for measuring the frequency of a desired resonant mode of a crystal arrangement, or other two-port device, during an automated operation. The crystal arrangement, or other two-port device, is placed into a test circuit and subjected to a sinusoidal test signal of known frequency. Based upon the output response of the crystal arrangement to the test signal, the frequency of the test signal is changed such that the test signal rapidly converges on a desired mode of operation of the crystal arrangement. This is accomplished by first noting a desired increase in amplitude of the output response of the crystal arrangement, followed by measuring an error signal related to the desired crystal arrangement mode of operation. When the error equals a predetermined value the frequency of the sinusoidal test signal is the frequency of the desired mode.