Abstract: An integrated spectrum analyzer for performing on-chip power spectrum measurements, includes a digital autocorrelator that includes an analog input for inputting analog signal samples from a chip, an analog-to-digital converter for converting the analog signal samples into digital signal samples, a storage register for storing a first converted digital signal sample for a period of time, a digital multiplier for multiplying the first stored digital signal after the period of time with a second undelayed digital signal sample to produce a product of multiplication, and an accumulator for accumulating a plurality of products of multiplication for each new period of time. The digital autocorrelator computes an autocorrelation function based on the analog signal samples and is integrally formed on the chip for performing power spectrum measurements on the analog signal samples to compute the autocorrelation function.

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: An apparatus for analyzing a spectrum of an input signal (?(t)) having at least one line with a center frequency ({circumflex over (?)}x) at the center of the line includes: a mixer for zero-mixing the input signal (?(t)) to produce a base band signal (z(t)) by sweeping a local oscillator frequency (?s) generated by a local oscillator, a resolution filter for filtering the base band signal (z(t)) to produce a filtered base band signal (y(t) ), and an envelope reconstruction means for reconstructing the envelope (E(?)) of the spectrum of the input signal (?(t)) by using an estimated amplitude (?x) at an estimated center frequency ({circumflex over (?)}x) of each line of the input signal (?(t)). Further, only the real component (I) of the base band signal (z(t)) is filtered with the resolution filter and the imaginary component (Q) is generated from the filtered base band signal (y(t)) by performing a Hilbert transform in a Hilbert filter arranged downstream of the resolution filter.

Abstract: A resonance-frequency measuring method is used for measuring a resonance frequency of an information recording/reproducing device reproducing information recorded on a medium by driving a mechanism unit. The resonance-frequency measuring method includes the measuring step of applying sine-wave oscillations at different frequencies one by one to the mechanism unit, and counting the number of times information reproduced upon application of each of the sine-wave oscillations differs from information indicating an aimed location, and the resonance-frequency determining step of determining the resonance frequency according to the number of times counted in the measuring step.

Abstract: An EMI (Electrical Magnetic Interference) test system is provided. The system includes a testing table, a horizontal antenna, a vertical antenna and a processing unit. The testing table is used for supporting an Equipment Under Test (EUT). The horizontal antenna is positioned at a first location in an EMI chamber. The vertical antenna is positioned at a second location in the EMI chamber. The vertical antenna and the horizontal antenna are used for receiving the electromagnetic wave radiated from the EUT, and producing a vertical electric wave and a horizontal electric wave respectively. The processing unit is coupled to the vertical antenna and the horizontal antenna for transforming and analyzing the vertical electric wave and the horizontal electric wave.

Abstract: A method and device for generating a clock signal accurately synchronized with a wobble signal including jitter even if there are manufacturing differences between voltage controlled oscillators. The clock signal generation device includes a voltage controlled oscillator for generating a clock signal corresponding to each of a plurality of oscillation characteristics. The clock signal generation device applies a test voltage to a voltage controlled oscillator with a voltage control device and sequentially identifies a plurality of oscillation characteristics set for the voltage controlled oscillator. The clock signal generation device selects one of the identified oscillation characteristics that has a frequency range with a generally middle part in which the frequency of a wobble signal is located and has a smaller gain.

Abstract: Transmission delay time measurement is performed on a signal propagation path between respective points of two printed circuit boards connected by a coaxial cable. Measurement is made of a frequency-domain response of the cable and a first time-domain response of the propagation path at its sending point and a second time-domain response of the propagation path at its receiving point. From the first time-domain response and the frequency-domain response, estimation is made of a third time-domain response of the propagation path that would be observed at the receiving point if there is no waveform distortion on the surface of the printed circuit boards. Time-domain correlation is calculated between the second and third time-domain responses. A first delay time is determined from the estimated time-domain response and a second delay time is determined from the correlation. The first and second delay times are summed to yield the transmission delay time of the propagation path.

Abstract: A spectrum analyzer with a compensation circuitry for prevention of measurement accuracy deterioration due to local oscillators phase noise.

Abstract: An inexpensive, small, low-power consumption, wide-band, high resolution spectrum analyzer is provided as a listening device for throw-away applications such as surveillance that involve deployment of large numbers of battery-powered spectrum analyzer modules to detect a signal source such as two-way radio traffic. Power requirements are minimized by the utilization of only one chirp generator to elongate battery life while providing a high resolution result. In order to minimize power drain the spectrum analyzer includes a single compound-chirp Fourier Transform generator. The compound chirp generator is used in one embodiment with a surface acoustic wave, SAW, dispersive delay line in conjunction with a surface electromagnetic wave, SEW dispensive delay line.

Abstract: A scheme to provide a spectral view of the signals present at the customer premises equipment by the network operator and includes a digital signal processor (DSP) or other signal processing apparatus integrated into a customer premises equipment (CPE) tuner in which the DSP or other signal processing apparatus is operational to perform a spectral analysis.

Abstract: Spectrum analyzer circuits and methods are provided which implement “zero-IF” (direct conversion) or “near-zero IF” (or very low IF) architectures that enable implementation of integrated (on-chip) spectrum analyzers for measuring the frequency spectrum of internal chip signals. An integrated spectrum analyzer circuit, which includes a zero IF or near-zero IF framework, enables a low-power compact design with sufficient resolution bandwidth for on-chip implementation and diagnostics of internal chip signals.

Abstract: A method of data acquisition for a digital instrument having a bandwidth. The method includes receiving a signal and associated trigger. Using that trigger, a plurality of signal values is sampled at multiple time intervals to create an acquisition record representing a continuous fractional segment of the signal. The plurality of samples meets the Nyquist requirement for the bandwidth but is in error according to at least one known error mechanism. The acquisition record is then processed with DSP techniques to produce a compensated acquisition record corrected for the at least one known error mechanism. Each associated compensated acquisition record is incorporated into a result acquisition record as a segment thereof corresponding to a continuous fractional segment of the signal whose signal values were sampled in an associated instance. An additional signal and additional associated trigger are received. The above steps are then repeated for the additional signal and additional associated trigger.

Abstract: A spectrum analyzer used for making a spectrum emission mask measurement reorganizes execution of the measurement so that all frequency bands to be measured at the same resolution bandwidth are measured in a single sweep, extending between the extreme frequency limits of those bands, thereby avoiding setup delays involved in specifying successive measurements for each band individually. Portions of each measurement which correspond to frequency bands to be measured at the respective resolution bandwidth of that measurement are extracted, resized as necessary, and assembled into a complete spectrum measurement.

Abstract: A method of measuring a device under test (“DUT”) includes applying a pulsed-RF input signal to the DUT and coupling an output of the DUT to a receiver having an output bandwidth selected to measure a center tone in an RF pulse response spectrum from the output of the DUT. The receiver is triggered so as to sample data output from the DUT during a window period, and stops taking data after the window period.

Abstract: In one embodiment, a method of automatically calibrating a network analyzer for measuring devices under test (DUTs) using a test fixture comprises generating a stimulus signal on a respective port that is coupled to the test fixture; measuring reflection of the stimulus signal on the respective port to generate measurement data, wherein the measurement data reflects a phase response of the test fixture; processing the measurement data to compensate for ripples generated by impedance mismatch at a coupling associated with the network analyzer and the test fixture; and adjusting a port extension setting of the network analyzer according to the processing.

Abstract: An object of this invention is to provide a band distribution inspecting device and band distribution inspecting method capable of carrying out inspection on whether or not a scattered oscillation signal oscillated containing a frequency variation from the fundamental frequency with the fundamental frequency as a reference point has a band distribution rapidly, with a simple way and at a cheap price. A scattered oscillation signal SSS inputted to a band distribution detecting section 22 is outputted as a predetermined band pass signal SBP through a band pass filter 17 having a predetermined pass band of a predetermined narrow-band width ?f within a band distribution. This signal is converted to a root-mean-square value by a smoother 19, smoothed by a capacitor C1 and transferred to a general purpose inspecting device 21 as a DC signal SAV.

Abstract: To analyze a network of conductors, especially an electrical power supply network, it is planned to measure the spectral (49) and temporal (50) nature of a signal available at a node of the network. An image (49–51) representing this state is produced. This image produced is compared with an expected image (52–55) showing an <<on >> state of one and/or the other of the appliances connected to this network. The state of the appliances, whether on or off, is deduced therefrom. This information can be used to optimize the use of the electrical power or to monitor the activity of the appliances concerned.

Abstract: A method of detecting a signal (S) of interest contained within a waveform (F) comprised of a plurality of signals within a frequency spectrum, as well as random noise. After first detecting the waveform, a determination is made as to whether the duration (Td) of the waveform is sufficient for subsequent processing. If the duration is not sufficient, the waveform is concatenated with itself to produce a waveform of sufficient duration. The concatenated waveform is then processed and the results supplied as an input to an oscillator (24) operating at a nominal output frequency. The oscillator cancels the effects of noise in the waveform and the frequency of the oscillator shifts to a different frequency which is a function of the signal of interest. The shift in output frequency of the oscillator is detected and analyzed to obtain the signal of interest. The oscillator can be either a general purpose oscillator or a Van der Pol oscillator.

Abstract: A spectrum analyzer includes a resonator board that in turn has a substrate and a plurality of resonators. Each resonator may include a first segment that includes a first segment discontinuity and that may also define a boundary and a second segment that has a second segment discontinuity. The second segment may be spaced from the first segment and wherein the second segment is disposed within the boundary defined by the first segment. The resonator board may also include a plurality of wires each of which may be generally parallel to each other and each having a resonator interposed therebetween.

Abstract: A frequency converter is tested. Labels for a plurality of mixing products are displayed. In response to a user selecting a first mixing product from the plurality of mixing products, appropriate frequencies for the first mixing product are calculated. Also, a measurement configuration for the first mixing product is determined.

Abstract: The values of the 6 complex parameters of a large-signal S-parameter model of a high frequency device-under-test are determined by using a frequency-offset probe-tone method. A relatively large one tone signal is applied to the input port of the device and a relatively small one tone signal having a frequency offset relative to the frequency of this large one tone signal is applied to the output port of the device. The 6 large-signal S-parameters are found by measuring and processing the spectral components of the incident and the scattered voltage waves at the device signal ports. These spectral components appear at 3 frequencies: at the frequency of the large one tone signal, at the frequency of the small one tone signal and at the frequency of the large one tone signal minus the frequency offset of the small one tone signal.

Abstract: A method and apparatus compensates for phase noise added by a spectrum analyzer from phase noise measurements of a signal under test (SUT) taken by the spectrum analyzer. The method comprises the steps of measuring the phase noise of the SUT, determining the added phase noise of the spectrum analyzer, and applying a mathematical correction to the measured phase noise. A spectrum analyzer apparatus that compensates for added phase noise comprises a controller portion, a memory portion, a signal conversion and detection portion, and a compensation algorithm stored in the memory portion. A system that compensates for added phase noise comprises a controller having a control algorithm and a spectrum analyzer. The compensation and control algorithms are computer programs that implement the method of the present invention.

Abstract: A method is provided of setting grids and/or markers on a screen of a display unit of a measuring apparatus. First, a mode of the apparatus is changed into a mode of setting the grids and/or the markers. Then, the grid and/or the marker serving as a reference is set. Then, a plurality of grids and/or markers are set, each of which provides an arbitrary interval with respect to the grid and/or the marker serving as reference.

Abstract: A low cost, low power and lightweight swept sine wave analysis system that is affordable to engineers, university laboratories and students, providing accurate magnitude and phase response measurements over a wide bandwidth is described. An analog mixer mixes a local oscillator signal with an amplified input signal allowing AC signal coupling between input stages. This minimizes errors due to DC and low frequency drift. A computer graphical interface is used for controlling the acquisition hardware in real time, displaying results on the computer screen, and making the graphical results and numerical results immediately available for inclusion in documentation or spreadsheet applications.

Abstract: A multirate spectral analyzer receives a data sequence through a tapped delay line (510) onto a plurality of filter channels, each of which includes a first decimator (520), a polyphase filter (530), and a second decimator (540). Each filter channel is coupled to a transform processor (550) which modulates the frequency response of the polyphase filters to a plurality of identical bandpass filters spaced evenly at 2?k/M intervals, where k=1, 2, . . . , M?1, and M is the number of filter channels. The transform processor (550) outputs a plurality of time series representative of the frequency component for each of the corresponding filter channels. By choosing a prototype filter order to be much larger than the number of filter channels, the effects of aliasing in the output are greatly reduced. The reduction in aliasing further allows, by prudent selection of the two decimators, for fractional temporal overlap to be implemented in the spectral estimates.

Abstract: A digital envelope detector (consisting of both hardware and software) that provides accurate measurements of changes of peak values of an AC signal (these peak values constitute the envelope of a signal). Such accurate envelope measurements are required, e.g., to optimize the accuracy and selectivity of chemical sensors. The envelope values required for these sensors can not be obtained with common instruments (e.g. voltmeters) since these meters require that successive peaks be the same amplitude. Therefore, they can not measure the envelope of a gradually increasing or decreasing AC signal from the chemical sensors. The only possible alternative to this invention is high speed, high resolution analog-to-digital conversion (ADC) followed by extensive statistical analysis. The ADC method is much more expensive, slower, and excessively complicated compared to the invention.

Abstract: A channel plan with a corresponding test plan are implemented in connection with a plurality of nodes that communicate signals. The channel plan has one or more predefined specifications for each of one or more signal channels on each of the nodes. The channel plan enables a monitoring system to, among other things, conduct automatic periodic test plans, comprising tests, on the nodes, based upon the predefined data specified in the channel plan. Each test plan prescribes measurement of at least one signal parameter, pertaining to one or more nodes as a whole and/or to one or more channels contained within the nodes. The monitoring system includes a spectrum analyzer, a switch enabling the spectrum analyzer to interface with the nodes, and a controller controlling the switch and the spectrum analyzer. The controller is configured to enable creation of and display the channel plan and test plan, based upon user inputs.

Abstract: Measurements for an eye diagram of a signal of interest are placed in a data structure that is examined to locate an eye opening of interest. The eye opening of interest has already been, or is subsequently, normalized into figure of merit units related to the operational voltage and timing requirements of the data receiver for that signal. The locations within the normalized eye opening may be taken as center locations for trial symmetric shapes that start out small and are enlarged until they first include locations not part of the normalized eye opening. The center of a largest such shape is mapped back into the units of the original eye diagram as optimum sampling parameters for data analysis equipment that uses the receiver to sample the signal once per unit interval to discover logical value. An alternative is to repeatedly remove the ‘outer layer’ of the normalized eye opening until only one location remains.

Abstract: A method and apparatus for interrogating a sample that exhibits molecular rotation includes placing the sample in a container having both magnetic and electromagnetic shielding, where Gaussian noise is injected into the sample. An electromagnetic time-domain signal composed of sample source radiation superimposed on the injected Guassian noise is detected, and this signal is used to generate a spectral plot that displays, at a selected power setting of the Gaussian noise source, low-frequency spectral components characteristic of the sample in a selected frequency range between DC and 50 kHz. In one embodiment, the spectral plot that is generated is a histogram of stochastic resonance events over the selected frequency range. From this spectrum, one or more low-frequency signal components that are characteristic of the sample being interrogated are identified.

Abstract: There are provided frequency analyzing method and apparatus, and a spectrum analyzer capable of reliably detecting and displaying a radio wave even if the radio wave is a frequency spread or low level one. A signal to be measured existing in a frequency band to be measured is extracted by a plurality of measurement signal extracting devices, and each of the extracted plural signals to be measured is frequency analyzed to compute a correlation value with respect to the plural results of frequency analyses. If the computed correlation value is equal to or greater than a preset value, a decision that the signal to be measured exists in the analyzed frequency is rendered, and if the computed correlation value is smaller than the preset value, a decision that the signal to be measured does not exist in the analyzed frequency is rendered. The decision results are displayed.

Abstract: Methods and systems are disclosed for analyzing interference caused by electromagnetic and other radiated emissions. A system includes an antenna, a spectrum analyzer, a computer and associated software. Configurations are defined for frequency ranges and tests are defined to include one or more configurations. After stationing the system in a desired location, a test may be selected for execution. Because a test may include multiple configurations, each representing a different frequency range or other parameters, multiple frequency ranges may be scanned by the spectrum analyzer without further intervention by a user. A data set is created for each configuration in each test that is executed.

Abstract: Methods, systems and circuits for analyzing the performance of a vehicle having an electrical system are provided which determine a shift point while the vehicle is being driven. The shift point is determined using acceleration data and RPM data generated from the electrical system.

Abstract: The invention relates to a method and an arrangement implementing the method for testing a transmitter part and receiver part in a transceiver. A signal in the transmitter part is mixed with a mixing signal for generating a signal to be connected to the receiver part, which generated signal is connected to the receiver part and the connected signal is compared with the transmitter part signal to test the transceiver. The mixing signal is generated by connecting a signal generated by means of a signal generator used in the operation of the transmitter part and/or receiver part to at least two signal branches, dividing the signal in the signal branches into at least two signals of different frequencies in the different signal branches, and generating a mixing signal from the signals of different frequencies.

Abstract: A method for measuring the EIRP (Effective Isotropic Radiated Power) of a satellite downlink carrier signal is performed by or under the control of a processor located, for example, at a technical operations center of a satellite communications company. The processor operates in accordance with a computer program which automatically identifies a carrier frequency corresponding to a customer, measures a level and bandwidth of the downlink signal at the customer carrier frequency, determines a level of a reference carrier signal, compares the level of the downlink signal to the level of the reference carrier signal, and determines EIRP power of the downlink signal based on the comparing step. The measured EIRP value is then compared to an EIRP value contractually assigned to the customer, and the difference determines the manner in which the measured EIRP value deviates from the assigned power.

Abstract: The present invention is directed to a centrifugal pump wherein voltage and current data are detected from voltage and current sensors in the motor controller of a pump motor. A power signal is then generated from the voltage and current data and spectrally analyzed to determine the presence of unwanted harmonics which are indicative of mechanical disturbances in the pump. As such, anomalies resulting from mechanical interference may be detected and a warning flag provided without additional transducers and other instruments on the motor or pump.

Abstract: A direct current machine monitoring system includes a sensor configured to monitor a load current of the machine and provide a signal indicative of an alternating current component of the load current; and a computer configured for: transforming the signal to provide a time domain transformation of the alternating current component of the load current, identifying features in the time domain transformation corresponding to sparking, and assessing a condition of the direct current machine using the features. The transform may be performed using a wavelet transform. The features may be used to determine a sparking intensity and a sparking frequency in the direct current machine, which may be used to determine a sparking index for assessing the condition of the direct current machine. The sparking index may be compared to a limit value, and statistical analysis may be performed on the sparking index.

Abstract: A test apparatus and method of measuring pulling of the frequency of an oscillator. The apparatus includes a bias tee, a power supply, a spectrum analyzer, a second power supply, a symmetrical resistive power splitter, a power meter and a synthesized signal generator. The method includes sweeping the synthesized signal generator frequency from the nominal frequency down to a first frequency. The first frequency is recorded when the oscillator goes out of frequency lock as a first pulling frequency. The synthesized signal generator frequency is then sweet from the nominal frequency up to a second frequency and the second pulling frequency is recorded when the oscillator goes out of frequency lock. The difference between the first and second pulling frequencies is the peak to peak pulling value.

Abstract: A system is provided for substantially continuously monitoring an electromagnetic intensity of short pulses of electromagnetic fields (E-fields) having frequencies within a broad frequency range. The system includes at least one antenna capable of sensing one or more pulses of E-fields and converting the pulses into radio frequency (RF) signals having an energy level correlated to the intensities of the E-fields. The system additionally includes at least one equalizer that normalizes the energy levels of RF signals across the broad range of frequencies and at least one modulation device that adjusts the energy levels of the RF signals output by the equalizer. The system further includes at least one RF power sensor for periodically measuring the energy levels of the RF signals output from the modulation device.

Abstract: A method of identifying a signal type uses parameters of the signal as a basis for automatic identification. A signal of interest is selected from a display of a spectral waveform for a specified frequency. An occupied bandwidth for the signal of interest is estimated and, if the occupied bandwidth is common to more than one known signal type, a complementary cumulative distribution function of peak power for the signal of interest is estimated. The signal type may be identified as a function of these parameters. Additionally the frequency of the signal of interest may be compared with a database of spectral assignments for known signal types to provide further information about the signal of interest.

Abstract: A spectrum analyzer is combined with the VNA in a housing measuring approximately 4 pounds with the spectrum analyzer portion operating from slightly above DC to above 3.0 GHz. The components for the spectrum analyzer are provided on a separate printed circuit board from the two printed circuit boards for the display and VNA components in the housing. The design of components for the printed circuit board enable a significant reduction of size from a typical spectrum analyzer which weighs 40 pounds or more and measures on the order of 2 feet by 3 feet by 0.5 feet.

Abstract: A preselector is omitted in a spectrum analyzer, for example, which is used to prevent an image signal from being inputted. In addition, an image signal of a signal which is located outside a range of set-up measured frequencies is suppressed as much as possible. For a range of set-up measured frequencies F1˜F2, and for each of a plurality of intermediate frequencies Fi, the frequency of the sweep signal is swept over a range F1+Fi˜F2+Fi to determine first measured data, and is also swept over a range F1?Fi˜F2?Fi to determine second measured data. The first and the second measured data are compared against each other for each measured frequency point, and if they are equal, the data value obtained or a data value having a minimum value unless they are not of an equal value is delivered to obtain measured data in which image data based on image signals has been suppressed.

Abstract: Sampling is performed. A strobe signal is generated from a first signal. Multiple sampled signals are sampled using the strobe signal. Each of the multiple sampled signals is synchronous with its own clock reference and each of clock references are asynchronous with respect to each other. Analog-to-digital conversion is performed on each sampled value of each of the multiple sampled signals. For each of the clock references that is not synchronous with the first signal, a phase comparison is performed between the clock reference and the first signal to produce a difference value. The difference value indicates a phase difference between the clock reference and the first signal. Analog-to-digital conversion of the difference value is performed at a frequency determined by the strobe signal.

Abstract: A frequency margin testing blade is adapted for use in a bladed server. The testing blade is further adapted to provide one or more output clock signals for use as clock inputs to one or more server blades internal to the bladed server in which the testing blade is installed and/or one or more server blades external to the bladed server in which the testing blade is installed.

Abstract: Methods are provided for embedding and/or de-embedding a network having an even number of ports into a device under test (DUT) having an odd number of ports. For example, a four-port network can be embedded/de-embedded into/from a three-port device under test (DUT). This is accomplished by embedding a virtual circulator into the three-port DUT to thereby generate an artificial four-port device. The four-port network is then embedded/de-embedded into/from the artificial four-port device to thereby generate a composite four-port device. The virtual circulator is then de-embedded from the composite four-port device to thereby generate a composite three-port device that is equivalent to the four-port network embedded/de-embedded into/from the three-port DUT.

Abstract: A noise injection method for characterizing common clock timing margin (jitter) includes injecting a single tone frequency, varying the amplitude of the injected frequency; measuring the signal produced at various signal amplitudes and analyzing the data obtained from measuring the signal. The obtained measurements may be analyzed using various characterizations such as measured jitter on input, measured jitter transfer, measured jitter tolerance, etc.

Abstract: A processor that utilizes the presence of harmonic components in a noisy signal environment to enhance the desired frequency spectrum of the signal. Received signal and noise are filtered to separate the harmonic components of the signal. These harmonic components are then combined in a prescribed manner to form a multiplicity of combined signals with varying harmonic content. The combined signals are then further processed to establish a signal detection.

Abstract: A receiver for analysing input RF signals comprises a first stage (51-55a) which includes an input for receiving one or more RF signals for analysis and a first local oscillator (51) having an output comprising a first plurality of frequencies. The input is mixed with the local oscillator output in a first mixer (55a) to generate a first intermediate frequency spectrum output. A second stage (56-59) includes a second local oscillator (58) adapted to produce as output a sweep signal traversing a second plurality of frequencies and a second mixer (55b) for combining said second local oscillator output with said first intermediate frequency output to generate a second intermediate frequency output.

Abstract: Dielectric spectroscopy is carried out by coupling non-radiated microwave energy from an antenna to a sample to detect changes in the permittivity of the sample within the antenna's near field. The frequency response of the antenna exhibits resonant frequencies in a frequency range of interest. Changes in the sample as a result of changes in environmental conditions of the sample are exhibited as changes in the antenna's resonant frequency or frequencies. The changes in the positions of the peaks with changes in environmental conditions can be correlated to changes in the condition of the sample, such as unfolding of proteins with increases in temperature of the sample.

Abstract: A device for verifying frequency of a clock signal generated from a clock signal generator includes a reference signal generator, a frequency divider and a comparative detector. A reference clock signal and a reset signal are provided by the reference signal generator. The frequency divider in communication with the reference signal generator and the clock signal generator receives and frequency-divides the clock signal into a bi-level divided clock signal in response to the reset signal. Then the comparative detector in communication with the frequency divider and the reference signal generator detects a level of the bi-level divided clock signal in response to the reset signal and the reference clock signal, and verifies frequency of the clock signal according to a period deviation range Te when the bi-level divided clock signal is detected to be a first level from the first to the (p−q)th detected points but a second level at the (p+1)th detected point.

Abstract: Measurements are obtained of a signal within each one of multiple ranges of a parameter. For each range a representative measurement value is derived together with the extent of the range. A respective graphical display element is defined for each range of the parameter, a first dimension of each display element (such as its height) being indicative of the representative measurement value for the respective range of the parameter, and a second dimension of the display element (such as its width) being indicative of the extent of that respective range of the parameter. A display of the measured signal throughout the multiple ranges of the parameter is generated, with the graphical display elements superimposed at positions corresponding to the respective ranges of the parameter.